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gems-kernel/source/THIRDPARTY/xnu/bsd/vfs/vfs_subr.c
Sam Sneed f5727805f2 add darwin/xnu functionality
2024-06-03 11:29:39 -05:00

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/*
*
* Copyright (c) 2000-2019 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
/*
* External virtual filesystem routines
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/mount_internal.h>
#include <sys/time.h>
#include <sys/lock.h>
#include <sys/vnode.h>
#include <sys/vnode_internal.h>
#include <sys/stat.h>
#include <sys/namei.h>
#include <sys/ucred.h>
#include <sys/buf_internal.h>
#include <sys/errno.h>
#include <kern/kalloc.h>
#include <sys/uio_internal.h>
#include <sys/uio.h>
#include <sys/domain.h>
#include <sys/mbuf.h>
#include <sys/syslog.h>
#include <sys/ubc_internal.h>
#include <sys/vm.h>
#include <sys/sysctl.h>
#include <sys/filedesc.h>
#include <sys/event.h>
#include <sys/kdebug.h>
#include <sys/kauth.h>
#include <sys/user.h>
#include <sys/systm.h>
#include <sys/kern_memorystatus.h>
#include <sys/lockf.h>
#include <sys/reboot.h>
#include <miscfs/fifofs/fifo.h>
#include <nfs/nfs.h>
#include <string.h>
#include <machine/machine_routines.h>
#include <kern/assert.h>
#include <mach/kern_return.h>
#include <kern/thread.h>
#include <kern/sched_prim.h>
#include <kern/smr.h>
#include <miscfs/specfs/specdev.h>
#include <mach/mach_types.h>
#include <mach/memory_object_types.h>
#include <mach/memory_object_control.h>
#include <kern/kalloc.h> /* kalloc()/kfree() */
#include <kern/clock.h> /* delay_for_interval() */
#include <libkern/coreanalytics/coreanalytics.h>
#include <libkern/OSAtomic.h> /* OSAddAtomic() */
#include <os/atomic_private.h>
#if defined(XNU_TARGET_OS_OSX)
#include <console/video_console.h>
#endif
#ifdef CONFIG_IOCOUNT_TRACE
#include <libkern/OSDebug.h>
#endif
#include <vm/vm_protos.h> /* vnode_pager_vrele() */
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
#include <vfs/vfs_disk_conditioner.h>
#include <libkern/section_keywords.h>
static LCK_GRP_DECLARE(vnode_lck_grp, "vnode");
static LCK_ATTR_DECLARE(vnode_lck_attr, 0, 0);
#if CONFIG_TRIGGERS
static LCK_GRP_DECLARE(trigger_vnode_lck_grp, "trigger_vnode");
static LCK_ATTR_DECLARE(trigger_vnode_lck_attr, 0, 0);
#endif
extern lck_mtx_t mnt_list_mtx_lock;
static KALLOC_TYPE_DEFINE(specinfo_zone, struct specinfo, KT_DEFAULT);
ZONE_DEFINE(vnode_zone, "vnodes",
sizeof(struct vnode), ZC_NOGC | ZC_ZFREE_CLEARMEM);
enum vtype iftovt_tab[16] = {
VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
};
int vttoif_tab[9] = {
0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
S_IFSOCK, S_IFIFO, S_IFMT,
};
/* XXX These should be in a BSD accessible Mach header, but aren't. */
extern void memory_object_mark_used(
memory_object_control_t control);
extern void memory_object_mark_unused(
memory_object_control_t control,
boolean_t rage);
extern void memory_object_mark_io_tracking(
memory_object_control_t control);
extern int paniclog_append_noflush(const char *format, ...);
/* XXX next prototytype should be from libsa/stdlib.h> but conflicts libkern */
__private_extern__ void qsort(
void * array,
size_t nmembers,
size_t member_size,
int (*)(const void *, const void *));
__private_extern__ void vntblinit(void);
__private_extern__ int unlink1(vfs_context_t, vnode_t, user_addr_t,
enum uio_seg, int);
static void vnode_list_add(vnode_t);
static void vnode_async_list_add(vnode_t);
static void vnode_list_remove(vnode_t);
static void vnode_list_remove_locked(vnode_t);
static void vnode_abort_advlocks(vnode_t);
static errno_t vnode_drain(vnode_t);
static void vgone(vnode_t, int flags);
static void vclean(vnode_t vp, int flag);
static void vnode_reclaim_internal(vnode_t, int, int, int);
static void vnode_dropiocount(vnode_t);
static vnode_t checkalias(vnode_t vp, dev_t nvp_rdev);
static int vnode_reload(vnode_t);
static int unmount_callback(mount_t, __unused void *);
static void insmntque(vnode_t vp, mount_t mp);
static int mount_getvfscnt(void);
static int mount_fillfsids(fsid_t *, int );
static void vnode_iterate_setup(mount_t);
int vnode_umount_preflight(mount_t, vnode_t, int);
static int vnode_iterate_prepare(mount_t);
static int vnode_iterate_reloadq(mount_t);
static void vnode_iterate_clear(mount_t);
static mount_t vfs_getvfs_locked(fsid_t *);
static int vn_create_reg(vnode_t dvp, vnode_t *vpp, struct nameidata *ndp,
struct vnode_attr *vap, uint32_t flags, int fmode, uint32_t *statusp, vfs_context_t ctx);
static int vnode_authattr_new_internal(vnode_t dvp, struct vnode_attr *vap, int noauth, uint32_t *defaulted_fieldsp, vfs_context_t ctx);
errno_t rmdir_remove_orphaned_appleDouble(vnode_t, vfs_context_t, int *);
#ifdef CONFIG_IOCOUNT_TRACE
static void record_vp(vnode_t vp, int count);
static TUNABLE(int, bootarg_vnode_iocount_trace, "vnode_iocount_trace", 0);
static TUNABLE(int, bootarg_uthread_iocount_trace, "uthread_iocount_trace", 0);
#endif /* CONFIG_IOCOUNT_TRACE */
#if CONFIG_JETSAM && (DEVELOPMENT || DEBUG)
static TUNABLE(bool, bootarg_no_vnode_jetsam, "-no_vnode_jetsam", false);
#endif /* CONFIG_JETSAM && (DEVELOPMENT || DEBUG) */
static TUNABLE(bool, bootarg_no_vnode_drain, "-no_vnode_drain", false);
__options_decl(freeable_vnode_level_t, uint32_t, {
DEALLOC_VNODE_NONE = 0,
DEALLOC_VNODE_ONLY_OVERFLOW = 1,
DEALLOC_VNODE_ALL = 2
});
#if XNU_TARGET_OS_OSX
static TUNABLE(freeable_vnode_level_t, bootarg_vn_dealloc_level, "vn_dealloc_level", DEALLOC_VNODE_NONE);
#else
static TUNABLE(freeable_vnode_level_t, bootarg_vn_dealloc_level, "vn_dealloc_level", DEALLOC_VNODE_ONLY_OVERFLOW);
#endif /* CONFIG_VNDEALLOC */
static freeable_vnode_level_t vn_dealloc_level = DEALLOC_VNODE_NONE;
boolean_t root_is_CF_drive = FALSE;
#if CONFIG_TRIGGERS
static int vnode_resolver_create(mount_t, vnode_t, struct vnode_trigger_param *, boolean_t external);
static void vnode_resolver_detach(vnode_t);
#endif
TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */
TAILQ_HEAD(deadlst, vnode) vnode_dead_list; /* vnode dead list */
TAILQ_HEAD(async_work_lst, vnode) vnode_async_work_list;
TAILQ_HEAD(ragelst, vnode) vnode_rage_list; /* vnode rapid age list */
struct timeval rage_tv;
int rage_limit = 0;
int ragevnodes = 0;
long reusablevnodes_max = LONG_MAX;
long reusablevnodes = 0;
int deadvnodes_low = 0;
int deadvnodes_high = 0;
int numvnodes_min = 0;
int numvnodes_max = 0;
uint64_t newvnode = 0;
unsigned long newvnode_nodead = 0;
static int vfs_unmountall_started = 0;
static int vfs_unmountall_finished = 0;
static uint64_t vfs_shutdown_last_completion_time;
#define RAGE_LIMIT_MIN 100
#define RAGE_TIME_LIMIT 5
VFS_SMR_DECLARE;
extern uint32_t nc_smr_enabled;
/*
* ROSV definitions
* NOTE: These are shadowed from PlatformSupport definitions, but XNU
* builds standalone.
*/
#define PLATFORM_DATA_VOLUME_MOUNT_POINT "/System/Volumes/Data"
/*
* These could be in PlatformSupport but aren't yet
*/
#define PLATFORM_PREBOOT_VOLUME_MOUNT_POINT "/System/Volumes/Preboot"
#define PLATFORM_RECOVERY_VOLUME_MOUNT_POINT "/System/Volumes/Recovery"
#if CONFIG_MOUNT_VM
#define PLATFORM_VM_VOLUME_MOUNT_POINT "/System/Volumes/VM"
#endif
struct mntlist mountlist; /* mounted filesystem list */
static int nummounts = 0;
static int print_busy_vnodes = 0; /* print out busy vnodes */
#if DIAGNOSTIC
#define VLISTCHECK(fun, vp, list) \
if ((vp)->v_freelist.tqe_prev == (struct vnode **)0xdeadb) \
panic("%s: %s vnode not on %slist", (fun), (list), (list));
#else
#define VLISTCHECK(fun, vp, list)
#endif /* DIAGNOSTIC */
#define VLISTNONE(vp) \
do { \
(vp)->v_freelist.tqe_next = (struct vnode *)0; \
(vp)->v_freelist.tqe_prev = (struct vnode **)0xdeadb; \
} while(0)
#define VONLIST(vp) \
((vp)->v_freelist.tqe_prev != (struct vnode **)0xdeadb)
/* remove a vnode from free vnode list */
#define VREMFREE(fun, vp) \
do { \
VLISTCHECK((fun), (vp), "free"); \
TAILQ_REMOVE(&vnode_free_list, (vp), v_freelist); \
VLISTNONE((vp)); \
freevnodes--; \
reusablevnodes--; \
} while(0)
/* remove a vnode from dead vnode list */
#define VREMDEAD(fun, vp) \
do { \
VLISTCHECK((fun), (vp), "dead"); \
TAILQ_REMOVE(&vnode_dead_list, (vp), v_freelist); \
VLISTNONE((vp)); \
vp->v_listflag &= ~VLIST_DEAD; \
deadvnodes--; \
if (vp->v_listflag & VLIST_NO_REUSE) { \
deadvnodes_noreuse--; \
} \
} while(0)
/* remove a vnode from async work vnode list */
#define VREMASYNC_WORK(fun, vp) \
do { \
VLISTCHECK((fun), (vp), "async_work"); \
TAILQ_REMOVE(&vnode_async_work_list, (vp), v_freelist); \
VLISTNONE((vp)); \
vp->v_listflag &= ~VLIST_ASYNC_WORK; \
async_work_vnodes--; \
if (!(vp->v_listflag & VLIST_NO_REUSE)) { \
reusablevnodes--; \
} \
} while(0)
/* remove a vnode from rage vnode list */
#define VREMRAGE(fun, vp) \
do { \
if ( !(vp->v_listflag & VLIST_RAGE)) \
panic("VREMRAGE: vp not on rage list"); \
VLISTCHECK((fun), (vp), "rage"); \
TAILQ_REMOVE(&vnode_rage_list, (vp), v_freelist); \
VLISTNONE((vp)); \
vp->v_listflag &= ~VLIST_RAGE; \
ragevnodes--; \
reusablevnodes--; \
} while(0)
static void async_work_continue(void);
static void vn_laundry_continue(void);
static void wakeup_laundry_thread(void);
static void vnode_smr_free(void *, size_t);
CA_EVENT(freeable_vnodes,
CA_INT, numvnodes_min,
CA_INT, numvnodes_max,
CA_INT, desiredvnodes,
CA_INT, numvnodes,
CA_INT, freevnodes,
CA_INT, deadvnodes,
CA_INT, freeablevnodes,
CA_INT, busyvnodes,
CA_BOOL, threshold_crossed);
static CA_EVENT_TYPE(freeable_vnodes) freeable_vnodes_telemetry;
static bool freeablevnodes_threshold_crossed = false;
/*
* Initialize the vnode management data structures.
*/
__private_extern__ void
vntblinit(void)
{
thread_t thread = THREAD_NULL;
int desiredvnodes_one_percent = desiredvnodes / 100;
TAILQ_INIT(&vnode_free_list);
TAILQ_INIT(&vnode_rage_list);
TAILQ_INIT(&vnode_dead_list);
TAILQ_INIT(&vnode_async_work_list);
TAILQ_INIT(&mountlist);
microuptime(&rage_tv);
rage_limit = desiredvnodes_one_percent;
if (rage_limit < RAGE_LIMIT_MIN) {
rage_limit = RAGE_LIMIT_MIN;
}
deadvnodes_low = desiredvnodes_one_percent;
if (deadvnodes_low > 300) {
deadvnodes_low = 300;
}
deadvnodes_high = deadvnodes_low * 2;
numvnodes_min = numvnodes_max = desiredvnodes;
if (bootarg_vn_dealloc_level == DEALLOC_VNODE_ONLY_OVERFLOW) {
numvnodes_max = desiredvnodes * 2;
vn_dealloc_level = bootarg_vn_dealloc_level;
} else if (bootarg_vn_dealloc_level == DEALLOC_VNODE_ALL) {
numvnodes_min = desiredvnodes_one_percent * 40;
numvnodes_max = desiredvnodes * 2;
reusablevnodes_max = (desiredvnodes_one_percent * 20) - deadvnodes_low;
vn_dealloc_level = bootarg_vn_dealloc_level;
}
bzero(&freeable_vnodes_telemetry, sizeof(CA_EVENT_TYPE(freeable_vnodes)));
freeable_vnodes_telemetry.numvnodes_min = numvnodes_min;
freeable_vnodes_telemetry.numvnodes_max = numvnodes_max;
freeable_vnodes_telemetry.desiredvnodes = desiredvnodes;
if (nc_smr_enabled) {
zone_enable_smr(vnode_zone, VFS_SMR(), &vnode_smr_free);
}
/*
* create worker threads
*/
kernel_thread_start((thread_continue_t)async_work_continue, NULL, &thread);
thread_deallocate(thread);
kernel_thread_start((thread_continue_t)vn_laundry_continue, NULL, &thread);
thread_deallocate(thread);
}
/* the timeout is in 10 msecs */
int
vnode_waitforwrites(vnode_t vp, int output_target, int slpflag, int slptimeout, const char *msg)
{
int error = 0;
struct timespec ts;
if (output_target < 0) {
return EINVAL;
}
KERNEL_DEBUG(0x3010280 | DBG_FUNC_START, (int)vp, output_target, vp->v_numoutput, 0, 0);
if (vp->v_numoutput > output_target) {
slpflag |= PDROP;
vnode_lock_spin(vp);
while ((vp->v_numoutput > output_target) && error == 0) {
if (output_target) {
vp->v_flag |= VTHROTTLED;
} else {
vp->v_flag |= VBWAIT;
}
ts.tv_sec = (slptimeout / 100);
ts.tv_nsec = (slptimeout % 1000) * 10 * NSEC_PER_USEC * 1000;
error = msleep((caddr_t)&vp->v_numoutput, &vp->v_lock, (slpflag | (PRIBIO + 1)), msg, &ts);
vnode_lock_spin(vp);
}
vnode_unlock(vp);
}
KERNEL_DEBUG(0x3010280 | DBG_FUNC_END, (int)vp, output_target, vp->v_numoutput, error, 0);
return error;
}
void
vnode_startwrite(vnode_t vp)
{
OSAddAtomic(1, &vp->v_numoutput);
}
void
vnode_writedone(vnode_t vp)
{
if (vp) {
int need_wakeup = 0;
OSAddAtomic(-1, &vp->v_numoutput);
vnode_lock_spin(vp);
if (vp->v_numoutput < 0) {
panic("vnode_writedone: numoutput < 0");
}
if ((vp->v_flag & VTHROTTLED)) {
vp->v_flag &= ~VTHROTTLED;
need_wakeup = 1;
}
if ((vp->v_flag & VBWAIT) && (vp->v_numoutput == 0)) {
vp->v_flag &= ~VBWAIT;
need_wakeup = 1;
}
vnode_unlock(vp);
if (need_wakeup) {
wakeup((caddr_t)&vp->v_numoutput);
}
}
}
int
vnode_hasdirtyblks(vnode_t vp)
{
struct cl_writebehind *wbp;
/*
* Not taking the buf_mtx as there is little
* point doing it. Even if the lock is taken the
* state can change right after that. If their
* needs to be a synchronization, it must be driven
* by the caller
*/
if (vp->v_dirtyblkhd.lh_first) {
return 1;
}
if (!UBCINFOEXISTS(vp)) {
return 0;
}
wbp = vp->v_ubcinfo->cl_wbehind;
if (wbp && (wbp->cl_number || wbp->cl_scmap)) {
return 1;
}
return 0;
}
int
vnode_hascleanblks(vnode_t vp)
{
/*
* Not taking the buf_mtx as there is little
* point doing it. Even if the lock is taken the
* state can change right after that. If their
* needs to be a synchronization, it must be driven
* by the caller
*/
if (vp->v_cleanblkhd.lh_first) {
return 1;
}
return 0;
}
void
vnode_iterate_setup(mount_t mp)
{
mp->mnt_lflag |= MNT_LITER;
}
int
vnode_umount_preflight(mount_t mp, vnode_t skipvp, int flags)
{
vnode_t vp;
int ret = 0;
TAILQ_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (vp->v_type == VDIR) {
continue;
}
if (vp == skipvp) {
continue;
}
if ((flags & SKIPSYSTEM) && ((vp->v_flag & VSYSTEM) || (vp->v_flag & VNOFLUSH))) {
continue;
}
if ((flags & SKIPSWAP) && (vp->v_flag & VSWAP)) {
continue;
}
if ((flags & WRITECLOSE) && (vp->v_writecount == 0 || vp->v_type != VREG)) {
continue;
}
/* Look for busy vnode */
if ((vp->v_usecount != 0) && ((vp->v_usecount - vp->v_kusecount) != 0)) {
ret = 1;
if (print_busy_vnodes && ((flags & FORCECLOSE) == 0)) {
vprint("vnode_umount_preflight - busy vnode", vp);
} else {
return ret;
}
} else if (vp->v_iocount > 0) {
/* Busy if iocount is > 0 for more than 3 seconds */
tsleep(&vp->v_iocount, PVFS, "vnode_drain_network", 3 * hz);
if (vp->v_iocount > 0) {
ret = 1;
if (print_busy_vnodes && ((flags & FORCECLOSE) == 0)) {
vprint("vnode_umount_preflight - busy vnode", vp);
} else {
return ret;
}
}
continue;
}
}
return ret;
}
/*
* This routine prepares iteration by moving all the vnodes to worker queue
* called with mount lock held
*/
int
vnode_iterate_prepare(mount_t mp)
{
vnode_t vp;
if (TAILQ_EMPTY(&mp->mnt_vnodelist)) {
/* nothing to do */
return 0;
}
vp = TAILQ_FIRST(&mp->mnt_vnodelist);
vp->v_mntvnodes.tqe_prev = &(mp->mnt_workerqueue.tqh_first);
mp->mnt_workerqueue.tqh_first = mp->mnt_vnodelist.tqh_first;
mp->mnt_workerqueue.tqh_last = mp->mnt_vnodelist.tqh_last;
TAILQ_INIT(&mp->mnt_vnodelist);
if (mp->mnt_newvnodes.tqh_first != NULL) {
panic("vnode_iterate_prepare: newvnode when entering vnode");
}
TAILQ_INIT(&mp->mnt_newvnodes);
return 1;
}
/* called with mount lock held */
int
vnode_iterate_reloadq(mount_t mp)
{
int moved = 0;
/* add the remaining entries in workerq to the end of mount vnode list */
if (!TAILQ_EMPTY(&mp->mnt_workerqueue)) {
struct vnode * mvp;
mvp = TAILQ_LAST(&mp->mnt_vnodelist, vnodelst);
/* Joining the workerque entities to mount vnode list */
if (mvp) {
mvp->v_mntvnodes.tqe_next = mp->mnt_workerqueue.tqh_first;
} else {
mp->mnt_vnodelist.tqh_first = mp->mnt_workerqueue.tqh_first;
}
mp->mnt_workerqueue.tqh_first->v_mntvnodes.tqe_prev = mp->mnt_vnodelist.tqh_last;
mp->mnt_vnodelist.tqh_last = mp->mnt_workerqueue.tqh_last;
TAILQ_INIT(&mp->mnt_workerqueue);
}
/* add the newvnodes to the head of mount vnode list */
if (!TAILQ_EMPTY(&mp->mnt_newvnodes)) {
struct vnode * nlvp;
nlvp = TAILQ_LAST(&mp->mnt_newvnodes, vnodelst);
mp->mnt_newvnodes.tqh_first->v_mntvnodes.tqe_prev = &mp->mnt_vnodelist.tqh_first;
nlvp->v_mntvnodes.tqe_next = mp->mnt_vnodelist.tqh_first;
if (mp->mnt_vnodelist.tqh_first) {
mp->mnt_vnodelist.tqh_first->v_mntvnodes.tqe_prev = &nlvp->v_mntvnodes.tqe_next;
} else {
mp->mnt_vnodelist.tqh_last = mp->mnt_newvnodes.tqh_last;
}
mp->mnt_vnodelist.tqh_first = mp->mnt_newvnodes.tqh_first;
TAILQ_INIT(&mp->mnt_newvnodes);
moved = 1;
}
return moved;
}
void
vnode_iterate_clear(mount_t mp)
{
mp->mnt_lflag &= ~MNT_LITER;
}
#if defined(__x86_64__)
#include <i386/panic_hooks.h>
struct vnode_iterate_panic_hook {
panic_hook_t hook;
mount_t mp;
struct vnode *vp;
};
static void
vnode_iterate_panic_hook(panic_hook_t *hook_)
{
struct vnode_iterate_panic_hook *hook = (struct vnode_iterate_panic_hook *)hook_;
panic_phys_range_t range;
uint64_t phys;
if (panic_phys_range_before(hook->mp, &phys, &range)) {
paniclog_append_noflush("mp = %p, phys = %p, prev (%p: %p-%p)\n",
hook->mp, phys, range.type, range.phys_start,
range.phys_start + range.len);
} else {
paniclog_append_noflush("mp = %p, phys = %p, prev (!)\n", hook->mp, phys);
}
if (panic_phys_range_before(hook->vp, &phys, &range)) {
paniclog_append_noflush("vp = %p, phys = %p, prev (%p: %p-%p)\n",
hook->vp, phys, range.type, range.phys_start,
range.phys_start + range.len);
} else {
paniclog_append_noflush("vp = %p, phys = %p, prev (!)\n", hook->vp, phys);
}
panic_dump_mem((void *)(((vm_offset_t)hook->mp - 4096) & ~4095), 12288);
}
#endif /* defined(__x86_64__) */
int
vnode_iterate(mount_t mp, int flags, int (*callout)(struct vnode *, void *),
void *arg)
{
struct vnode *vp;
int vid, retval;
int ret = 0;
/*
* The mount iterate mutex is held for the duration of the iteration.
* This can be done by a state flag on the mount structure but we can
* run into priority inversion issues sometimes.
* Using a mutex allows us to benefit from the priority donation
* mechanisms in the kernel for locks. This mutex should never be
* acquired in spin mode and it should be acquired before attempting to
* acquire the mount lock.
*/
mount_iterate_lock(mp);
mount_lock(mp);
vnode_iterate_setup(mp);
/* If it returns 0 then there is nothing to do */
retval = vnode_iterate_prepare(mp);
if (retval == 0) {
vnode_iterate_clear(mp);
mount_unlock(mp);
mount_iterate_unlock(mp);
return ret;
}
#if defined(__x86_64__)
struct vnode_iterate_panic_hook hook;
hook.mp = mp;
hook.vp = NULL;
panic_hook(&hook.hook, vnode_iterate_panic_hook);
#endif
/* iterate over all the vnodes */
while (!TAILQ_EMPTY(&mp->mnt_workerqueue)) {
vp = TAILQ_FIRST(&mp->mnt_workerqueue);
#if defined(__x86_64__)
hook.vp = vp;
#endif
TAILQ_REMOVE(&mp->mnt_workerqueue, vp, v_mntvnodes);
TAILQ_INSERT_TAIL(&mp->mnt_vnodelist, vp, v_mntvnodes);
vid = vp->v_id;
if ((vp->v_data == NULL) || (vp->v_type == VNON) || (vp->v_mount != mp)) {
continue;
}
vnode_hold(vp);
mount_unlock(mp);
if (vget_internal(vp, vid, (flags | VNODE_NODEAD | VNODE_WITHID | VNODE_NOSUSPEND))) {
mount_lock(mp);
vnode_drop(vp);
continue;
}
vnode_drop(vp);
if (flags & VNODE_RELOAD) {
/*
* we're reloading the filesystem
* cast out any inactive vnodes...
*/
if (vnode_reload(vp)) {
/* vnode will be recycled on the refcount drop */
vnode_put(vp);
mount_lock(mp);
continue;
}
}
retval = callout(vp, arg);
switch (retval) {
case VNODE_RETURNED:
case VNODE_RETURNED_DONE:
vnode_put(vp);
if (retval == VNODE_RETURNED_DONE) {
mount_lock(mp);
ret = 0;
goto out;
}
break;
case VNODE_CLAIMED_DONE:
mount_lock(mp);
ret = 0;
goto out;
case VNODE_CLAIMED:
default:
break;
}
mount_lock(mp);
}
out:
#if defined(__x86_64__)
panic_unhook(&hook.hook);
#endif
(void)vnode_iterate_reloadq(mp);
vnode_iterate_clear(mp);
mount_unlock(mp);
mount_iterate_unlock(mp);
return ret;
}
void
mount_lock_renames(mount_t mp)
{
lck_mtx_lock(&mp->mnt_renamelock);
}
void
mount_unlock_renames(mount_t mp)
{
lck_mtx_unlock(&mp->mnt_renamelock);
}
void
mount_iterate_lock(mount_t mp)
{
lck_mtx_lock(&mp->mnt_iter_lock);
}
void
mount_iterate_unlock(mount_t mp)
{
lck_mtx_unlock(&mp->mnt_iter_lock);
}
void
mount_lock(mount_t mp)
{
lck_mtx_lock(&mp->mnt_mlock);
}
void
mount_lock_spin(mount_t mp)
{
lck_mtx_lock_spin(&mp->mnt_mlock);
}
void
mount_unlock(mount_t mp)
{
lck_mtx_unlock(&mp->mnt_mlock);
}
void
mount_ref(mount_t mp, int locked)
{
if (!locked) {
mount_lock_spin(mp);
}
mp->mnt_count++;
if (!locked) {
mount_unlock(mp);
}
}
void
mount_drop(mount_t mp, int locked)
{
if (!locked) {
mount_lock_spin(mp);
}
mp->mnt_count--;
if (mp->mnt_count == 0 && (mp->mnt_lflag & MNT_LDRAIN)) {
wakeup(&mp->mnt_lflag);
}
if (!locked) {
mount_unlock(mp);
}
}
int
mount_iterref(mount_t mp, int locked)
{
int retval = 0;
if (!locked) {
mount_list_lock();
}
if (mp->mnt_iterref < 0) {
retval = 1;
} else {
mp->mnt_iterref++;
}
if (!locked) {
mount_list_unlock();
}
return retval;
}
int
mount_isdrained(mount_t mp, int locked)
{
int retval;
if (!locked) {
mount_list_lock();
}
if (mp->mnt_iterref < 0) {
retval = 1;
} else {
retval = 0;
}
if (!locked) {
mount_list_unlock();
}
return retval;
}
void
mount_iterdrop(mount_t mp)
{
mount_list_lock();
mp->mnt_iterref--;
wakeup(&mp->mnt_iterref);
mount_list_unlock();
}
void
mount_iterdrain(mount_t mp)
{
mount_list_lock();
while (mp->mnt_iterref) {
msleep((caddr_t)&mp->mnt_iterref, &mnt_list_mtx_lock, PVFS, "mount_iterdrain", NULL);
}
/* mount iterations drained */
mp->mnt_iterref = -1;
mount_list_unlock();
}
void
mount_iterreset(mount_t mp)
{
mount_list_lock();
if (mp->mnt_iterref == -1) {
mp->mnt_iterref = 0;
}
mount_list_unlock();
}
/* always called with mount lock held */
int
mount_refdrain(mount_t mp)
{
if (mp->mnt_lflag & MNT_LDRAIN) {
panic("already in drain");
}
mp->mnt_lflag |= MNT_LDRAIN;
while (mp->mnt_count) {
msleep((caddr_t)&mp->mnt_lflag, &mp->mnt_mlock, PVFS, "mount_drain", NULL);
}
if (mp->mnt_vnodelist.tqh_first != NULL) {
panic("mount_refdrain: dangling vnode");
}
mp->mnt_lflag &= ~MNT_LDRAIN;
return 0;
}
/* Tags the mount point as not supportine extended readdir for NFS exports */
void
mount_set_noreaddirext(mount_t mp)
{
mount_lock(mp);
mp->mnt_kern_flag |= MNTK_DENY_READDIREXT;
mount_unlock(mp);
}
/*
* Mark a mount point as busy. Used to synchronize access and to delay
* unmounting.
*/
int
vfs_busy(mount_t mp, int flags)
{
restart:
if (mp->mnt_lflag & MNT_LDEAD) {
return ENOENT;
}
mount_lock(mp);
if (mp->mnt_lflag & MNT_LUNMOUNT) {
if (flags & LK_NOWAIT || mp->mnt_lflag & MNT_LDEAD) {
mount_unlock(mp);
return ENOENT;
}
/*
* Since all busy locks are shared except the exclusive
* lock granted when unmounting, the only place that a
* wakeup needs to be done is at the release of the
* exclusive lock at the end of dounmount.
*/
mp->mnt_lflag |= MNT_LWAIT;
msleep((caddr_t)mp, &mp->mnt_mlock, (PVFS | PDROP), "vfsbusy", NULL);
return ENOENT;
}
mount_unlock(mp);
lck_rw_lock_shared(&mp->mnt_rwlock);
/*
* Until we are granted the rwlock, it's possible for the mount point to
* change state, so re-evaluate before granting the vfs_busy.
*/
if (mp->mnt_lflag & (MNT_LDEAD | MNT_LUNMOUNT)) {
lck_rw_done(&mp->mnt_rwlock);
goto restart;
}
return 0;
}
/*
* Free a busy filesystem.
*/
void
vfs_unbusy(mount_t mp)
{
lck_rw_done(&mp->mnt_rwlock);
}
static void
vfs_rootmountfailed(mount_t mp)
{
mount_list_lock();
mp->mnt_vtable->vfc_refcount--;
mount_list_unlock();
vfs_unbusy(mp);
if (nc_smr_enabled) {
vfs_smr_synchronize();
}
mount_lock_destroy(mp);
#if CONFIG_MACF
mac_mount_label_destroy(mp);
#endif
zfree(mount_zone, mp);
}
/*
* Lookup a filesystem type, and if found allocate and initialize
* a mount structure for it.
*
* Devname is usually updated by mount(8) after booting.
*/
static mount_t
vfs_rootmountalloc_internal(struct vfstable *vfsp, const char *devname)
{
mount_t mp;
mp = zalloc_flags(mount_zone, Z_WAITOK | Z_ZERO);
/* Initialize the default IO constraints */
mp->mnt_maxreadcnt = mp->mnt_maxwritecnt = MAXPHYS;
mp->mnt_segreadcnt = mp->mnt_segwritecnt = 32;
mp->mnt_maxsegreadsize = mp->mnt_maxreadcnt;
mp->mnt_maxsegwritesize = mp->mnt_maxwritecnt;
mp->mnt_devblocksize = DEV_BSIZE;
mp->mnt_alignmentmask = PAGE_MASK;
mp->mnt_ioqueue_depth = MNT_DEFAULT_IOQUEUE_DEPTH;
mp->mnt_ioscale = 1;
mp->mnt_ioflags = 0;
mp->mnt_realrootvp = NULLVP;
mp->mnt_authcache_ttl = CACHED_LOOKUP_RIGHT_TTL;
mp->mnt_throttle_mask = LOWPRI_MAX_NUM_DEV - 1;
mp->mnt_devbsdunit = 0;
mount_lock_init(mp);
(void)vfs_busy(mp, LK_NOWAIT);
TAILQ_INIT(&mp->mnt_vnodelist);
TAILQ_INIT(&mp->mnt_workerqueue);
TAILQ_INIT(&mp->mnt_newvnodes);
mp->mnt_vtable = vfsp;
mp->mnt_op = vfsp->vfc_vfsops;
mp->mnt_flag = MNT_RDONLY | MNT_ROOTFS;
mp->mnt_vnodecovered = NULLVP;
//mp->mnt_stat.f_type = vfsp->vfc_typenum;
mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK;
mount_list_lock();
vfsp->vfc_refcount++;
mount_list_unlock();
strlcpy(mp->mnt_vfsstat.f_fstypename, vfsp->vfc_name, MFSTYPENAMELEN);
mp->mnt_vfsstat.f_mntonname[0] = '/';
/* XXX const poisoning layering violation */
(void) copystr((const void *)devname, mp->mnt_vfsstat.f_mntfromname, MAXPATHLEN - 1, NULL);
#if CONFIG_MACF
mac_mount_label_init(mp);
mac_mount_label_associate(vfs_context_kernel(), mp);
#endif
return mp;
}
errno_t
vfs_rootmountalloc(const char *fstypename, const char *devname, mount_t *mpp)
{
struct vfstable *vfsp;
for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
if (!strncmp(vfsp->vfc_name, fstypename,
sizeof(vfsp->vfc_name))) {
break;
}
}
if (vfsp == NULL) {
return ENODEV;
}
*mpp = vfs_rootmountalloc_internal(vfsp, devname);
if (*mpp) {
return 0;
}
return ENOMEM;
}
#define DBG_MOUNTROOT (FSDBG_CODE(DBG_MOUNT, 0))
/*
* Find an appropriate filesystem to use for the root. If a filesystem
* has not been preselected, walk through the list of known filesystems
* trying those that have mountroot routines, and try them until one
* works or we have tried them all.
*/
extern int (*mountroot)(void);
int
vfs_mountroot(void)
{
#if CONFIG_MACF
struct vnode *vp;
#endif
struct vfstable *vfsp;
vfs_context_t ctx = vfs_context_kernel();
struct vfs_attr vfsattr;
int error;
mount_t mp;
vnode_t bdevvp_rootvp;
/*
* Reset any prior "unmounting everything" state. This handles the
* situation where mount root and then unmountall and re-mountroot
* a new image (see bsd/kern/imageboot.c).
*/
vfs_unmountall_started = vfs_unmountall_finished = 0;
OSMemoryBarrier();
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_START);
if (mountroot != NULL) {
/*
* used for netboot which follows a different set of rules
*/
error = (*mountroot)();
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_END, error, 0);
return error;
}
if ((error = bdevvp(rootdev, &rootvp))) {
printf("vfs_mountroot: can't setup bdevvp\n");
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_END, error, 1);
return error;
}
/*
* 4951998 - code we call in vfc_mountroot may replace rootvp
* so keep a local copy for some house keeping.
*/
bdevvp_rootvp = rootvp;
for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
if (vfsp->vfc_mountroot == NULL
&& !ISSET(vfsp->vfc_vfsflags, VFC_VFSCANMOUNTROOT)) {
continue;
}
mp = vfs_rootmountalloc_internal(vfsp, "root_device");
mp->mnt_devvp = rootvp;
if (vfsp->vfc_mountroot) {
error = (*vfsp->vfc_mountroot)(mp, rootvp, ctx);
} else {
error = VFS_MOUNT(mp, rootvp, 0, ctx);
}
if (!error) {
if (bdevvp_rootvp != rootvp) {
/*
* rootvp changed...
* bump the iocount and fix up mnt_devvp for the
* new rootvp (it will already have a usecount taken)...
* drop the iocount and the usecount on the orignal
* since we are no longer going to use it...
*/
vnode_getwithref(rootvp);
mp->mnt_devvp = rootvp;
vnode_rele(bdevvp_rootvp);
vnode_put(bdevvp_rootvp);
}
mp->mnt_devvp->v_specflags |= SI_MOUNTEDON;
vfs_unbusy(mp);
mount_list_add(mp);
/*
* cache the IO attributes for the underlying physical media...
* an error return indicates the underlying driver doesn't
* support all the queries necessary... however, reasonable
* defaults will have been set, so no reason to bail or care
*/
vfs_init_io_attributes(rootvp, mp);
if (mp->mnt_ioflags & MNT_IOFLAGS_FUSION_DRIVE) {
root_is_CF_drive = TRUE;
}
/*
* Shadow the VFC_VFSNATIVEXATTR flag to MNTK_EXTENDED_ATTRS.
*/
if (mp->mnt_vtable->vfc_vfsflags & VFC_VFSNATIVEXATTR) {
mp->mnt_kern_flag |= MNTK_EXTENDED_ATTRS;
}
if (mp->mnt_vtable->vfc_vfsflags & VFC_VFSPREFLIGHT) {
mp->mnt_kern_flag |= MNTK_UNMOUNT_PREFLIGHT;
}
#if defined(XNU_TARGET_OS_OSX)
uint32_t speed;
if (MNTK_VIRTUALDEV & mp->mnt_kern_flag) {
speed = 128;
} else if (disk_conditioner_mount_is_ssd(mp)) {
speed = 7 * 256;
} else {
speed = 256;
}
vc_progress_setdiskspeed(speed);
#endif /* XNU_TARGET_OS_OSX */
/*
* Probe root file system for additional features.
*/
(void)VFS_START(mp, 0, ctx);
VFSATTR_INIT(&vfsattr);
VFSATTR_WANTED(&vfsattr, f_capabilities);
if (vfs_getattr(mp, &vfsattr, ctx) == 0 &&
VFSATTR_IS_SUPPORTED(&vfsattr, f_capabilities)) {
if ((vfsattr.f_capabilities.capabilities[VOL_CAPABILITIES_INTERFACES] & VOL_CAP_INT_EXTENDED_ATTR) &&
(vfsattr.f_capabilities.valid[VOL_CAPABILITIES_INTERFACES] & VOL_CAP_INT_EXTENDED_ATTR)) {
mp->mnt_kern_flag |= MNTK_EXTENDED_ATTRS;
}
#if NAMEDSTREAMS
if ((vfsattr.f_capabilities.capabilities[VOL_CAPABILITIES_INTERFACES] & VOL_CAP_INT_NAMEDSTREAMS) &&
(vfsattr.f_capabilities.valid[VOL_CAPABILITIES_INTERFACES] & VOL_CAP_INT_NAMEDSTREAMS)) {
mp->mnt_kern_flag |= MNTK_NAMED_STREAMS;
}
#endif
if ((vfsattr.f_capabilities.capabilities[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_PATH_FROM_ID) &&
(vfsattr.f_capabilities.valid[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_PATH_FROM_ID)) {
mp->mnt_kern_flag |= MNTK_PATH_FROM_ID;
}
if ((vfsattr.f_capabilities.capabilities[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_DIR_HARDLINKS) &&
(vfsattr.f_capabilities.valid[VOL_CAPABILITIES_FORMAT] & VOL_CAP_FMT_DIR_HARDLINKS)) {
mp->mnt_kern_flag |= MNTK_DIR_HARDLINKS;
}
}
/*
* get rid of iocount reference returned
* by bdevvp (or picked up by us on the substitued
* rootvp)... it (or we) will have also taken
* a usecount reference which we want to keep
*/
vnode_put(rootvp);
#if CONFIG_MACF
if ((vfs_flags(mp) & MNT_MULTILABEL) == 0) {
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_END, 0, 2);
return 0;
}
error = VFS_ROOT(mp, &vp, ctx);
if (error) {
printf("%s() VFS_ROOT() returned %d\n",
__func__, error);
dounmount(mp, MNT_FORCE, 0, ctx);
goto fail;
}
error = vnode_label(mp, NULL, vp, NULL, 0, ctx);
/*
* get rid of reference provided by VFS_ROOT
*/
vnode_put(vp);
if (error) {
printf("%s() vnode_label() returned %d\n",
__func__, error);
dounmount(mp, MNT_FORCE, 0, ctx);
goto fail;
}
#endif
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_END, 0, 3);
return 0;
}
vfs_rootmountfailed(mp);
#if CONFIG_MACF
fail:
#endif
if (error != EINVAL) {
printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error);
}
}
KDBG_RELEASE(DBG_MOUNTROOT | DBG_FUNC_END, error ? error : ENODEV, 4);
return ENODEV;
}
static int
cache_purge_callback(mount_t mp, __unused void * arg)
{
cache_purgevfs(mp);
return VFS_RETURNED;
}
extern lck_rw_t rootvnode_rw_lock;
extern void set_rootvnode(vnode_t);
static int
mntonname_fixup_callback(mount_t mp, __unused void *arg)
{
int error = 0;
if ((strncmp(&mp->mnt_vfsstat.f_mntonname[0], "/", sizeof("/")) == 0) ||
(strncmp(&mp->mnt_vfsstat.f_mntonname[0], "/dev", sizeof("/dev")) == 0)) {
return 0;
}
if ((error = vfs_busy(mp, LK_NOWAIT))) {
printf("vfs_busy failed with %d for %s\n", error, mp->mnt_vfsstat.f_mntonname);
return -1;
}
size_t pathlen = MAXPATHLEN;
if ((error = vn_getpath_ext(mp->mnt_vnodecovered, NULL, mp->mnt_vfsstat.f_mntonname, &pathlen, VN_GETPATH_FSENTER))) {
printf("vn_getpath_ext failed with %d for mnt_vnodecovered of %s\n", error, mp->mnt_vfsstat.f_mntonname);
}
vfs_unbusy(mp);
return error;
}
static int
clear_mntk_backs_root_callback(mount_t mp, __unused void *arg)
{
lck_rw_lock_exclusive(&mp->mnt_rwlock);
mp->mnt_kern_flag &= ~MNTK_BACKS_ROOT;
lck_rw_done(&mp->mnt_rwlock);
return VFS_RETURNED;
}
static int
verify_incoming_rootfs(vnode_t *incoming_rootvnodep, vfs_context_t ctx,
vfs_switch_root_flags_t flags)
{
mount_t mp;
vnode_t tdp;
vnode_t incoming_rootvnode_with_iocount = *incoming_rootvnodep;
vnode_t incoming_rootvnode_with_usecount = NULLVP;
int error = 0;
if (vnode_vtype(incoming_rootvnode_with_iocount) != VDIR) {
printf("Incoming rootfs path not a directory\n");
error = ENOTDIR;
goto done;
}
/*
* Before we call VFS_ROOT, we have to let go of the iocount already
* acquired, but before doing that get a usecount.
*/
vnode_ref_ext(incoming_rootvnode_with_iocount, 0, VNODE_REF_FORCE);
incoming_rootvnode_with_usecount = incoming_rootvnode_with_iocount;
vnode_lock_spin(incoming_rootvnode_with_usecount);
if ((mp = incoming_rootvnode_with_usecount->v_mount)) {
mp->mnt_crossref++;
vnode_unlock(incoming_rootvnode_with_usecount);
} else {
vnode_unlock(incoming_rootvnode_with_usecount);
printf("Incoming rootfs root vnode does not have associated mount\n");
error = ENOTDIR;
goto done;
}
if (vfs_busy(mp, LK_NOWAIT)) {
printf("Incoming rootfs root vnode mount is busy\n");
error = ENOENT;
goto out;
}
vnode_put(incoming_rootvnode_with_iocount);
incoming_rootvnode_with_iocount = NULLVP;
error = VFS_ROOT(mp, &tdp, ctx);
if (error) {
printf("Could not get rootvnode of incoming rootfs\n");
} else if (tdp != incoming_rootvnode_with_usecount) {
vnode_put(tdp);
tdp = NULLVP;
printf("Incoming rootfs root vnode mount is is not a mountpoint\n");
error = EINVAL;
goto out_busy;
} else {
incoming_rootvnode_with_iocount = tdp;
tdp = NULLVP;
}
if ((flags & VFSSR_VIRTUALDEV_PROHIBITED) != 0) {
if (mp->mnt_flag & MNTK_VIRTUALDEV) {
error = ENODEV;
}
if (error) {
printf("Incoming rootfs is backed by a virtual device; cannot switch to it");
goto out_busy;
}
}
out_busy:
vfs_unbusy(mp);
out:
vnode_lock(incoming_rootvnode_with_usecount);
mp->mnt_crossref--;
if (mp->mnt_crossref < 0) {
panic("mount cross refs -ve");
}
vnode_unlock(incoming_rootvnode_with_usecount);
done:
if (incoming_rootvnode_with_usecount) {
vnode_rele(incoming_rootvnode_with_usecount);
incoming_rootvnode_with_usecount = NULLVP;
}
if (error && incoming_rootvnode_with_iocount) {
vnode_put(incoming_rootvnode_with_iocount);
incoming_rootvnode_with_iocount = NULLVP;
}
*incoming_rootvnodep = incoming_rootvnode_with_iocount;
return error;
}
/*
* vfs_switch_root()
*
* Move the current root volume, and put a different volume at the root.
*
* incoming_vol_old_path: This is the path where the incoming root volume
* is mounted when this function begins.
* outgoing_vol_new_path: This is the path where the outgoing root volume
* will be mounted when this function (successfully) ends.
* Note: Do not use a leading slash.
*
* Volumes mounted at several fixed points (including /dev) will be preserved
* at the same absolute path. That means they will move within the folder
* hierarchy during the pivot operation. For example, /dev before the pivot
* will be at /dev after the pivot.
*
* If any filesystem has MNTK_BACKS_ROOT set, it will be cleared. If the
* incoming root volume is actually a disk image backed by some other
* filesystem, it is the caller's responsibility to re-set MNTK_BACKS_ROOT
* as appropriate.
*/
int
vfs_switch_root(const char *incoming_vol_old_path,
const char *outgoing_vol_new_path,
vfs_switch_root_flags_t flags)
{
// grumble grumble
#define countof(x) (sizeof(x) / sizeof(x[0]))
struct preserved_mount {
vnode_t pm_rootvnode;
mount_t pm_mount;
vnode_t pm_new_covered_vp;
vnode_t pm_old_covered_vp;
const char *pm_path;
};
vfs_context_t ctx = vfs_context_kernel();
vnode_t incoming_rootvnode = NULLVP;
vnode_t outgoing_vol_new_covered_vp = NULLVP;
vnode_t incoming_vol_old_covered_vp = NULLVP;
mount_t outgoing = NULL;
mount_t incoming = NULL;
struct preserved_mount devfs = { NULLVP, NULL, NULLVP, NULLVP, "dev" };
struct preserved_mount preboot = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/Preboot" };
struct preserved_mount recovery = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/Recovery" };
struct preserved_mount vm = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/VM" };
struct preserved_mount update = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/Update" };
struct preserved_mount iscPreboot = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/iSCPreboot" };
struct preserved_mount hardware = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/Hardware" };
struct preserved_mount xarts = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/xarts" };
struct preserved_mount factorylogs = { NULLVP, NULL, NULLVP, NULLVP, "FactoryLogs" };
struct preserved_mount idiags = { NULLVP, NULL, NULLVP, NULLVP, "System/Volumes/Diags" };
struct preserved_mount *preserved[10];
preserved[0] = &devfs;
preserved[1] = &preboot;
preserved[2] = &recovery;
preserved[3] = &vm;
preserved[4] = &update;
preserved[5] = &iscPreboot;
preserved[6] = &hardware;
preserved[7] = &xarts;
preserved[8] = &factorylogs;
preserved[9] = &idiags;
int error;
printf("%s : shuffling mount points : %s <-> / <-> %s\n", __FUNCTION__, incoming_vol_old_path, outgoing_vol_new_path);
if (outgoing_vol_new_path[0] == '/') {
// I should have written this to be more helpful and just advance the pointer forward past the slash
printf("Do not use a leading slash in outgoing_vol_new_path\n");
return EINVAL;
}
// Set incoming_rootvnode.
// Find the vnode representing the mountpoint of the new root
// filesystem. That will be the new root directory.
error = vnode_lookup(incoming_vol_old_path, 0, &incoming_rootvnode, ctx);
if (error) {
printf("Incoming rootfs root vnode not found\n");
error = ENOENT;
goto done;
}
/*
* This function drops the icoount and sets the vnode to NULL on error.
*/
error = verify_incoming_rootfs(&incoming_rootvnode, ctx, flags);
if (error) {
goto done;
}
/*
* Set outgoing_vol_new_covered_vp.
* Find the vnode representing the future mountpoint of the old
* root filesystem, inside the directory incoming_rootvnode.
* Right now it's at "/incoming_vol_old_path/outgoing_vol_new_path".
* soon it will become "/oldrootfs_path_after", which will be covered.
*/
error = vnode_lookupat(outgoing_vol_new_path, 0, &outgoing_vol_new_covered_vp, ctx, incoming_rootvnode);
if (error) {
printf("Outgoing rootfs path not found, abandoning / switch, error = %d\n", error);
error = ENOENT;
goto done;
}
if (vnode_vtype(outgoing_vol_new_covered_vp) != VDIR) {
printf("Outgoing rootfs path is not a directory, abandoning / switch\n");
error = ENOTDIR;
goto done;
}
/*
* Find the preserved mounts - see if they are mounted. Get their root
* vnode if they are. If they aren't, leave rootvnode NULL which will
* be the signal to ignore this mount later on.
*
* Also get preserved mounts' new_covered_vp.
* Find the node representing the folder "dev" inside the directory newrootvnode.
* Right now it's at "/incoming_vol_old_path/dev".
* Soon it will become /dev, which will be covered by the devfs mountpoint.
*/
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
error = vnode_lookupat(pmi->pm_path, 0, &pmi->pm_rootvnode, ctx, rootvnode);
if (error) {
printf("skipping preserved mountpoint because not found or error: %d: %s\n", error, pmi->pm_path);
// not fatal. try the next one in the list.
continue;
}
bool is_mountpoint = false;
vnode_lock_spin(pmi->pm_rootvnode);
if ((pmi->pm_rootvnode->v_flag & VROOT) != 0) {
is_mountpoint = true;
}
vnode_unlock(pmi->pm_rootvnode);
if (!is_mountpoint) {
printf("skipping preserved mountpoint because not a mountpoint: %s\n", pmi->pm_path);
vnode_put(pmi->pm_rootvnode);
pmi->pm_rootvnode = NULLVP;
// not fatal. try the next one in the list.
continue;
}
error = vnode_lookupat(pmi->pm_path, 0, &pmi->pm_new_covered_vp, ctx, incoming_rootvnode);
if (error) {
printf("preserved new mount directory not found or error: %d: %s\n", error, pmi->pm_path);
error = ENOENT;
goto done;
}
if (vnode_vtype(pmi->pm_new_covered_vp) != VDIR) {
printf("preserved new mount directory not directory: %s\n", pmi->pm_path);
error = ENOTDIR;
goto done;
}
printf("will preserve mountpoint across pivot: /%s\n", pmi->pm_path);
}
/*
* --
* At this point, everything has been prepared and all error conditions
* have been checked. We check everything we can before this point;
* from now on we start making destructive changes, and we can't stop
* until we reach the end.
* ----
*/
/* this usecount is transferred to the mnt_vnodecovered */
vnode_ref_ext(outgoing_vol_new_covered_vp, 0, VNODE_REF_FORCE);
/* this usecount is transferred to set_rootvnode */
vnode_ref_ext(incoming_rootvnode, 0, VNODE_REF_FORCE);
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode == NULLVP) {
continue;
}
/* this usecount is transferred to the mnt_vnodecovered */
vnode_ref_ext(pmi->pm_new_covered_vp, 0, VNODE_REF_FORCE);
/* The new_covered_vp is a mountpoint from now on. */
vnode_lock_spin(pmi->pm_new_covered_vp);
pmi->pm_new_covered_vp->v_flag |= VMOUNTEDHERE;
vnode_unlock(pmi->pm_new_covered_vp);
}
/* The outgoing_vol_new_covered_vp is a mountpoint from now on. */
vnode_lock_spin(outgoing_vol_new_covered_vp);
outgoing_vol_new_covered_vp->v_flag |= VMOUNTEDHERE;
vnode_unlock(outgoing_vol_new_covered_vp);
/*
* Identify the mount_ts of the mounted filesystems that are being
* manipulated: outgoing rootfs, incoming rootfs, and the preserved
* mounts.
*/
outgoing = rootvnode->v_mount;
incoming = incoming_rootvnode->v_mount;
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode == NULLVP) {
continue;
}
pmi->pm_mount = pmi->pm_rootvnode->v_mount;
}
lck_rw_lock_exclusive(&rootvnode_rw_lock);
/* Setup incoming as the new rootfs */
lck_rw_lock_exclusive(&incoming->mnt_rwlock);
incoming_vol_old_covered_vp = incoming->mnt_vnodecovered;
incoming->mnt_vnodecovered = NULLVP;
strlcpy(incoming->mnt_vfsstat.f_mntonname, "/", MAXPATHLEN);
incoming->mnt_flag |= MNT_ROOTFS;
lck_rw_done(&incoming->mnt_rwlock);
/*
* The preserved mountpoints will now be moved to
* incoming_rootnode/pm_path, and then by the end of the function,
* since incoming_rootnode is going to /, the preserved mounts
* will be end up back at /pm_path
*/
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode == NULLVP) {
continue;
}
lck_rw_lock_exclusive(&pmi->pm_mount->mnt_rwlock);
pmi->pm_old_covered_vp = pmi->pm_mount->mnt_vnodecovered;
pmi->pm_mount->mnt_vnodecovered = pmi->pm_new_covered_vp;
vnode_lock_spin(pmi->pm_new_covered_vp);
pmi->pm_new_covered_vp->v_mountedhere = pmi->pm_mount;
SET(pmi->pm_new_covered_vp->v_flag, VMOUNTEDHERE);
vnode_unlock(pmi->pm_new_covered_vp);
lck_rw_done(&pmi->pm_mount->mnt_rwlock);
}
/*
* The old root volume now covers outgoing_vol_new_covered_vp
* on the new root volume. Remove the ROOTFS marker.
* Now it is to be found at outgoing_vol_new_path
*/
lck_rw_lock_exclusive(&outgoing->mnt_rwlock);
outgoing->mnt_vnodecovered = outgoing_vol_new_covered_vp;
strlcpy(outgoing->mnt_vfsstat.f_mntonname, "/", MAXPATHLEN);
strlcat(outgoing->mnt_vfsstat.f_mntonname, outgoing_vol_new_path, MAXPATHLEN);
outgoing->mnt_flag &= ~MNT_ROOTFS;
vnode_lock_spin(outgoing_vol_new_covered_vp);
outgoing_vol_new_covered_vp->v_mountedhere = outgoing;
vnode_unlock(outgoing_vol_new_covered_vp);
lck_rw_done(&outgoing->mnt_rwlock);
if (!(outgoing->mnt_kern_flag & MNTK_VIRTUALDEV) &&
(TAILQ_FIRST(&mountlist) == outgoing)) {
vfs_setmntsystem(outgoing);
}
/*
* Finally, remove the mount_t linkage from the previously covered
* vnodes on the old root volume. These were incoming_vol_old_path,
* and each preserved mounts's "/pm_path". The filesystems previously
* mounted there have already been moved away.
*/
vnode_lock_spin(incoming_vol_old_covered_vp);
incoming_vol_old_covered_vp->v_flag &= ~VMOUNT;
incoming_vol_old_covered_vp->v_mountedhere = NULL;
vnode_unlock(incoming_vol_old_covered_vp);
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode == NULLVP) {
continue;
}
vnode_lock_spin(pmi->pm_old_covered_vp);
CLR(pmi->pm_old_covered_vp->v_flag, VMOUNTEDHERE);
pmi->pm_old_covered_vp->v_mountedhere = NULL;
vnode_unlock(pmi->pm_old_covered_vp);
}
/*
* Clear the name cache since many cached names are now invalid.
*/
vfs_iterate(0 /* flags */, cache_purge_callback, NULL);
/*
* Actually change the rootvnode! And finally drop the lock that
* prevents concurrent vnode_lookups.
*/
set_rootvnode(incoming_rootvnode);
lck_rw_unlock_exclusive(&rootvnode_rw_lock);
if (!(incoming->mnt_kern_flag & MNTK_VIRTUALDEV) &&
!(outgoing->mnt_kern_flag & MNTK_VIRTUALDEV)) {
/*
* Switch the order of mount structures in the mountlist, new root
* mount moves to the head of the list followed by /dev and the other
* preserved mounts then all the preexisting mounts (old rootfs + any
* others)
*/
mount_list_lock();
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode == NULLVP) {
continue;
}
TAILQ_REMOVE(&mountlist, pmi->pm_mount, mnt_list);
TAILQ_INSERT_HEAD(&mountlist, pmi->pm_mount, mnt_list);
}
TAILQ_REMOVE(&mountlist, incoming, mnt_list);
TAILQ_INSERT_HEAD(&mountlist, incoming, mnt_list);
mount_list_unlock();
}
/*
* Fixups across all volumes
*/
vfs_iterate(0 /* flags */, mntonname_fixup_callback, NULL);
vfs_iterate(0 /* flags */, clear_mntk_backs_root_callback, NULL);
error = 0;
done:
for (size_t i = 0; i < countof(preserved); i++) {
struct preserved_mount *pmi = preserved[i];
if (pmi->pm_rootvnode) {
vnode_put(pmi->pm_rootvnode);
}
if (pmi->pm_new_covered_vp) {
vnode_put(pmi->pm_new_covered_vp);
}
if (pmi->pm_old_covered_vp) {
vnode_rele(pmi->pm_old_covered_vp);
}
}
if (outgoing_vol_new_covered_vp) {
vnode_put(outgoing_vol_new_covered_vp);
}
if (incoming_vol_old_covered_vp) {
vnode_rele(incoming_vol_old_covered_vp);
}
if (incoming_rootvnode) {
vnode_put(incoming_rootvnode);
}
printf("%s : done shuffling mount points with error: %d\n", __FUNCTION__, error);
return error;
}
/*
* Mount the Recovery volume of a container
*/
int
vfs_mount_recovery(void)
{
#if CONFIG_MOUNT_PREBOOTRECOVERY
int error = 0;
error = vnode_get(rootvnode);
if (error) {
/* root must be mounted first */
printf("vnode_get(rootvnode) failed with error %d\n", error);
return error;
}
char recoverypath[] = PLATFORM_RECOVERY_VOLUME_MOUNT_POINT; /* !const because of internal casting */
/* Mount the recovery volume */
printf("attempting kernel mount for recovery volume... \n");
error = kernel_mount(rootvnode->v_mount->mnt_vfsstat.f_fstypename, NULLVP, NULLVP,
recoverypath, (rootvnode->v_mount), 0, 0, (KERNEL_MOUNT_RECOVERYVOL), vfs_context_kernel());
if (error) {
printf("Failed to mount recovery volume (%d)\n", error);
} else {
printf("mounted recovery volume\n");
}
vnode_put(rootvnode);
return error;
#else
return 0;
#endif
}
/*
* Lookup a mount point by filesystem identifier.
*/
struct mount *
vfs_getvfs(fsid_t *fsid)
{
return mount_list_lookupby_fsid(fsid, 0, 0);
}
static struct mount *
vfs_getvfs_locked(fsid_t *fsid)
{
return mount_list_lookupby_fsid(fsid, 1, 0);
}
struct mount *
vfs_getvfs_with_vfsops(fsid_t *fsid, const struct vfsops * const ops)
{
mount_t mp = mount_list_lookupby_fsid(fsid, 0, 0);
if (mp != NULL && mp->mnt_op != ops) {
mp = NULL;
}
return mp;
}
struct mount *
vfs_getvfs_by_mntonname(char *path)
{
mount_t retmp = (mount_t)0;
mount_t mp;
mount_list_lock();
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
if (!strncmp(mp->mnt_vfsstat.f_mntonname, path,
sizeof(mp->mnt_vfsstat.f_mntonname))) {
retmp = mp;
if (mount_iterref(retmp, 1)) {
retmp = NULL;
}
goto out;
}
}
out:
mount_list_unlock();
return retmp;
}
/* generation number for creation of new fsids */
u_short mntid_gen = 0;
/*
* Get a new unique fsid
*/
void
vfs_getnewfsid(struct mount *mp)
{
fsid_t tfsid;
int mtype;
mount_list_lock();
/* generate a new fsid */
mtype = mp->mnt_vtable->vfc_typenum;
if (++mntid_gen == 0) {
mntid_gen++;
}
tfsid.val[0] = makedev(nblkdev + mtype, mntid_gen);
tfsid.val[1] = mtype;
while (vfs_getvfs_locked(&tfsid)) {
if (++mntid_gen == 0) {
mntid_gen++;
}
tfsid.val[0] = makedev(nblkdev + mtype, mntid_gen);
}
mp->mnt_vfsstat.f_fsid.val[0] = tfsid.val[0];
mp->mnt_vfsstat.f_fsid.val[1] = tfsid.val[1];
mount_list_unlock();
}
/*
* Routines having to do with the management of the vnode table.
*/
extern int(**dead_vnodeop_p)(void *);
long numvnodes, freevnodes, deadvnodes, async_work_vnodes;
long busyvnodes = 0;
long deadvnodes_noreuse = 0;
int32_t freeablevnodes = 0;
uint64_t allocedvnodes = 0;
uint64_t deallocedvnodes = 0;
int async_work_timed_out = 0;
int async_work_handled = 0;
int dead_vnode_wanted = 0;
int dead_vnode_waited = 0;
/*
* Move a vnode from one mount queue to another.
*/
static void
insmntque(vnode_t vp, mount_t mp)
{
mount_t lmp;
/*
* Delete from old mount point vnode list, if on one.
*/
if ((lmp = vp->v_mount) != NULL && lmp != dead_mountp) {
if ((vp->v_lflag & VNAMED_MOUNT) == 0) {
panic("insmntque: vp not in mount vnode list");
}
vp->v_lflag &= ~VNAMED_MOUNT;
mount_lock_spin(lmp);
mount_drop(lmp, 1);
if (vp->v_mntvnodes.tqe_next == NULL) {
if (TAILQ_LAST(&lmp->mnt_vnodelist, vnodelst) == vp) {
TAILQ_REMOVE(&lmp->mnt_vnodelist, vp, v_mntvnodes);
} else if (TAILQ_LAST(&lmp->mnt_newvnodes, vnodelst) == vp) {
TAILQ_REMOVE(&lmp->mnt_newvnodes, vp, v_mntvnodes);
} else if (TAILQ_LAST(&lmp->mnt_workerqueue, vnodelst) == vp) {
TAILQ_REMOVE(&lmp->mnt_workerqueue, vp, v_mntvnodes);
}
} else {
vp->v_mntvnodes.tqe_next->v_mntvnodes.tqe_prev = vp->v_mntvnodes.tqe_prev;
*vp->v_mntvnodes.tqe_prev = vp->v_mntvnodes.tqe_next;
}
vp->v_mntvnodes.tqe_next = NULL;
vp->v_mntvnodes.tqe_prev = NULL;
mount_unlock(lmp);
vnode_drop(vp);
return;
}
/*
* Insert into list of vnodes for the new mount point, if available.
*/
if ((vp->v_mount = mp) != NULL) {
mount_lock_spin(mp);
if ((vp->v_mntvnodes.tqe_next != 0) && (vp->v_mntvnodes.tqe_prev != 0)) {
panic("vp already in mount list");
}
if (mp->mnt_lflag & MNT_LITER) {
TAILQ_INSERT_HEAD(&mp->mnt_newvnodes, vp, v_mntvnodes);
} else {
TAILQ_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes);
}
if (vp->v_lflag & VNAMED_MOUNT) {
panic("insmntque: vp already in mount vnode list");
}
vnode_hold(vp);
vp->v_lflag |= VNAMED_MOUNT;
mount_ref(mp, 1);
mount_unlock(mp);
}
}
/*
* Create a vnode for a block device.
* Used for root filesystem, argdev, and swap areas.
* Also used for memory file system special devices.
*/
int
bdevvp(dev_t dev, vnode_t *vpp)
{
vnode_t nvp;
int error;
struct vnode_fsparam vfsp;
struct vfs_context context;
if (dev == NODEV) {
*vpp = NULLVP;
return ENODEV;
}
context.vc_thread = current_thread();
context.vc_ucred = FSCRED;
vfsp.vnfs_mp = (struct mount *)0;
vfsp.vnfs_vtype = VBLK;
vfsp.vnfs_str = "bdevvp";
vfsp.vnfs_dvp = NULL;
vfsp.vnfs_fsnode = NULL;
vfsp.vnfs_cnp = NULL;
vfsp.vnfs_vops = spec_vnodeop_p;
vfsp.vnfs_rdev = dev;
vfsp.vnfs_filesize = 0;
vfsp.vnfs_flags = VNFS_NOCACHE | VNFS_CANTCACHE;
vfsp.vnfs_marksystem = 0;
vfsp.vnfs_markroot = 0;
if ((error = vnode_create(VNCREATE_FLAVOR, VCREATESIZE, &vfsp, &nvp))) {
*vpp = NULLVP;
return error;
}
vnode_lock_spin(nvp);
nvp->v_flag |= VBDEVVP;
nvp->v_tag = VT_NON; /* set this to VT_NON so during aliasing it can be replaced */
vnode_unlock(nvp);
if ((error = vnode_ref(nvp))) {
panic("bdevvp failed: vnode_ref");
return error;
}
if ((error = VNOP_FSYNC(nvp, MNT_WAIT, &context))) {
panic("bdevvp failed: fsync");
return error;
}
if ((error = buf_invalidateblks(nvp, BUF_WRITE_DATA, 0, 0))) {
panic("bdevvp failed: invalidateblks");
return error;
}
#if CONFIG_MACF
/*
* XXXMAC: We can't put a MAC check here, the system will
* panic without this vnode.
*/
#endif /* MAC */
if ((error = VNOP_OPEN(nvp, FREAD, &context))) {
panic("bdevvp failed: open");
return error;
}
*vpp = nvp;
return 0;
}
/*
* Check to see if the new vnode represents a special device
* for which we already have a vnode (either because of
* bdevvp() or because of a different vnode representing
* the same block device). If such an alias exists, deallocate
* the existing contents and return the aliased vnode. The
* caller is responsible for filling it with its new contents.
*/
static vnode_t
checkalias(struct vnode *nvp, dev_t nvp_rdev)
{
struct vnode *vp;
struct vnode **vpp;
struct specinfo *sin = NULL;
int vid = 0;
vpp = &speclisth[SPECHASH(nvp_rdev)];
loop:
SPECHASH_LOCK();
for (vp = *vpp; vp; vp = vp->v_specnext) {
if (nvp_rdev == vp->v_rdev && nvp->v_type == vp->v_type) {
vid = vp->v_id;
vnode_hold(vp);
break;
}
}
SPECHASH_UNLOCK();
if (vp) {
found_alias:
if (vnode_getwithvid(vp, vid)) {
vnode_drop(vp);
goto loop;
}
vnode_drop(vp);
/*
* Termination state is checked in vnode_getwithvid
*/
vnode_lock(vp);
/*
* Alias, but not in use, so flush it out.
*/
if ((vp->v_iocount == 1) && (vp->v_usecount == 0)) {
vnode_hold(vp);
vnode_reclaim_internal(vp, 1, 1, 0);
vnode_put_locked(vp);
vnode_drop_and_unlock(vp);
goto loop;
}
}
if (vp == NULL || vp->v_tag != VT_NON) {
if (sin == NULL) {
sin = zalloc_flags(specinfo_zone, Z_WAITOK | Z_ZERO);
} else {
bzero(sin, sizeof(struct specinfo));
}
nvp->v_specinfo = sin;
nvp->v_rdev = nvp_rdev;
nvp->v_specflags = 0;
nvp->v_speclastr = -1;
nvp->v_specinfo->si_opencount = 0;
nvp->v_specinfo->si_initted = 0;
nvp->v_specinfo->si_throttleable = 0;
nvp->v_specinfo->si_devbsdunit = LOWPRI_MAX_NUM_DEV;
SPECHASH_LOCK();
/* We dropped the lock, someone could have added */
if (vp == NULLVP) {
for (vp = *vpp; vp; vp = vp->v_specnext) {
if (nvp_rdev == vp->v_rdev && nvp->v_type == vp->v_type) {
vid = vp->v_id;
vnode_hold(vp);
SPECHASH_UNLOCK();
goto found_alias;
}
}
}
nvp->v_hashchain = vpp;
nvp->v_specnext = *vpp;
*vpp = nvp;
if (vp != NULLVP) {
nvp->v_specflags |= SI_ALIASED;
vp->v_specflags |= SI_ALIASED;
SPECHASH_UNLOCK();
vnode_put_locked(vp);
vnode_unlock(vp);
} else {
SPECHASH_UNLOCK();
}
return NULLVP;
}
if (sin) {
zfree(specinfo_zone, sin);
}
if ((vp->v_flag & (VBDEVVP | VDEVFLUSH)) != 0) {
return vp;
}
panic("checkalias with VT_NON vp that shouldn't: %p", vp);
return vp;
}
/*
* Get a reference on a particular vnode and lock it if requested.
* If the vnode was on the inactive list, remove it from the list.
* If the vnode was on the free list, remove it from the list and
* move it to inactive list as needed.
* The vnode lock bit is set if the vnode is being eliminated in
* vgone. The process is awakened when the transition is completed,
* and an error returned to indicate that the vnode is no longer
* usable (possibly having been changed to a new file system type).
*/
int
vget_internal(vnode_t vp, int vid, int vflags)
{
int error = 0;
vnode_lock_spin(vp);
if ((vflags & VNODE_WRITEABLE) && (vp->v_writecount == 0)) {
/*
* vnode to be returned only if it has writers opened
*/
error = EINVAL;
} else {
error = vnode_getiocount(vp, vid, vflags);
}
vnode_unlock(vp);
return error;
}
/*
* Returns: 0 Success
* ENOENT No such file or directory [terminating]
*/
int
vnode_ref(vnode_t vp)
{
return vnode_ref_ext(vp, 0, 0);
}
/*
* Returns: 0 Success
* ENOENT No such file or directory [terminating]
*/
int
vnode_ref_ext(vnode_t vp, int fmode, int flags)
{
int error = 0;
vnode_lock_spin(vp);
/*
* once all the current call sites have been fixed to insure they have
* taken an iocount, we can toughen this assert up and insist that the
* iocount is non-zero... a non-zero usecount doesn't insure correctness
*/
if (vp->v_iocount <= 0 && vp->v_usecount <= 0) {
panic("vnode_ref_ext: vp %p has no valid reference %d, %d", vp, vp->v_iocount, vp->v_usecount);
}
/*
* if you are the owner of drain/termination, can acquire usecount
*/
if ((flags & VNODE_REF_FORCE) == 0) {
if ((vp->v_lflag & (VL_DRAIN | VL_TERMINATE | VL_DEAD))) {
if (vp->v_owner != current_thread()) {
error = ENOENT;
goto out;
}
}
}
/* Enable atomic ops on v_usecount without the vnode lock */
os_atomic_inc(&vp->v_usecount, relaxed);
if (fmode & FWRITE) {
if (++vp->v_writecount <= 0) {
panic("vnode_ref_ext: v_writecount");
}
}
if (fmode & O_EVTONLY) {
if (++vp->v_kusecount <= 0) {
panic("vnode_ref_ext: v_kusecount");
}
}
if (vp->v_flag & VRAGE) {
struct uthread *ut;
ut = current_uthread();
if (!(current_proc()->p_lflag & P_LRAGE_VNODES) &&
!(ut->uu_flag & UT_RAGE_VNODES)) {
/*
* a 'normal' process accessed this vnode
* so make sure its no longer marked
* for rapid aging... also, make sure
* it gets removed from the rage list...
* when v_usecount drops back to 0, it
* will be put back on the real free list
*/
vp->v_flag &= ~VRAGE;
vp->v_references = 0;
vnode_list_remove(vp);
}
}
if (vp->v_usecount == 1 && vp->v_type == VREG && !(vp->v_flag & VSYSTEM)) {
if (vp->v_ubcinfo) {
vnode_lock_convert(vp);
memory_object_mark_used(vp->v_ubcinfo->ui_control);
}
}
out:
vnode_unlock(vp);
return error;
}
boolean_t
vnode_on_reliable_media(vnode_t vp)
{
mount_t mp = vp->v_mount;
/*
* A NULL mountpoint would imply it's not attached to a any filesystem.
* This can only happen with a vnode created by bdevvp(). We'll consider
* those as not unreliable as the primary use of this function is determine
* which vnodes are to be handed off to the async cleaner thread for
* reclaim.
*/
if (!mp || (!(mp->mnt_kern_flag & MNTK_VIRTUALDEV) && (mp->mnt_flag & MNT_LOCAL))) {
return TRUE;
}
return FALSE;
}
static void
vnode_async_list_add_locked(vnode_t vp)
{
if (VONLIST(vp) || (vp->v_lflag & (VL_TERMINATE | VL_DEAD))) {
panic("vnode_async_list_add: %p is in wrong state", vp);
}
TAILQ_INSERT_HEAD(&vnode_async_work_list, vp, v_freelist);
vp->v_listflag |= VLIST_ASYNC_WORK;
async_work_vnodes++;
if (!(vp->v_listflag & VLIST_NO_REUSE)) {
reusablevnodes++;
}
if (vp->v_flag & VCANDEALLOC) {
os_atomic_dec(&busyvnodes, relaxed);
}
}
static void
vnode_async_list_add(vnode_t vp)
{
vnode_list_lock();
if (VONLIST(vp)) {
if (!(vp->v_listflag & VLIST_ASYNC_WORK)) {
vnode_list_remove_locked(vp);
vnode_async_list_add_locked(vp);
}
} else {
vnode_async_list_add_locked(vp);
}
vnode_list_unlock();
wakeup(&vnode_async_work_list);
}
/*
* put the vnode on appropriate free list.
* called with vnode LOCKED
*/
static void
vnode_list_add(vnode_t vp)
{
boolean_t need_dead_wakeup = FALSE;
bool no_busy_decrement = false;
#if DIAGNOSTIC
lck_mtx_assert(&vp->v_lock, LCK_MTX_ASSERT_OWNED);
#endif
again:
/*
* if it is already on a list or non zero references return
*/
if (VONLIST(vp) || (vp->v_usecount != 0) || (vp->v_iocount != 0) || (vp->v_lflag & VL_TERMINATE)) {
return;
}
/*
* In vclean, we might have deferred ditching locked buffers
* because something was still referencing them (indicated by
* usecount). We can ditch them now.
*/
if (ISSET(vp->v_lflag, VL_DEAD)
&& (!LIST_EMPTY(&vp->v_cleanblkhd) || !LIST_EMPTY(&vp->v_dirtyblkhd))) {
++vp->v_iocount; // Probably not necessary, but harmless
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_unlock(vp);
buf_invalidateblks(vp, BUF_INVALIDATE_LOCKED, 0, 0);
vnode_lock(vp);
vnode_dropiocount(vp);
goto again;
}
vnode_list_lock();
if (!(vp->v_lflag & VL_DEAD) && (vp->v_listflag & VLIST_NO_REUSE)) {
if (!(vp->v_listflag & VLIST_ASYNC_WORK)) {
vnode_async_list_add_locked(vp);
}
no_busy_decrement = true;
} else if ((vp->v_flag & VRAGE) && !(vp->v_lflag & VL_DEAD)) {
/*
* add the new guy to the appropriate end of the RAGE list
*/
if ((vp->v_flag & VAGE)) {
TAILQ_INSERT_HEAD(&vnode_rage_list, vp, v_freelist);
} else {
TAILQ_INSERT_TAIL(&vnode_rage_list, vp, v_freelist);
}
vp->v_listflag |= VLIST_RAGE;
ragevnodes++;
reusablevnodes++;
wakeup_laundry_thread();
/*
* reset the timestamp for the last inserted vp on the RAGE
* queue to let new_vnode know that its not ok to start stealing
* from this list... as long as we're actively adding to this list
* we'll push out the vnodes we want to donate to the real free list
* once we stop pushing, we'll let some time elapse before we start
* stealing them in the new_vnode routine
*/
microuptime(&rage_tv);
} else {
/*
* if VL_DEAD, insert it at head of the dead list
* else insert at tail of LRU list or at head if VAGE is set
*/
if ((vp->v_lflag & VL_DEAD)) {
if (vp->v_flag & VCANDEALLOC) {
TAILQ_INSERT_TAIL(&vnode_dead_list, vp, v_freelist);
if (vp->v_listflag & VLIST_NO_REUSE) {
deadvnodes_noreuse++;
}
} else {
TAILQ_INSERT_HEAD(&vnode_dead_list, vp, v_freelist);
}
vp->v_listflag |= VLIST_DEAD;
deadvnodes++;
if (dead_vnode_wanted) {
dead_vnode_wanted--;
need_dead_wakeup = TRUE;
}
} else if ((vp->v_flag & VAGE)) {
TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
vp->v_flag &= ~VAGE;
freevnodes++;
reusablevnodes++;
wakeup_laundry_thread();
} else {
TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
freevnodes++;
reusablevnodes++;
wakeup_laundry_thread();
}
}
if ((vp->v_flag & VCANDEALLOC) && !no_busy_decrement) {
os_atomic_dec(&busyvnodes, relaxed);
}
vnode_list_unlock();
if (need_dead_wakeup == TRUE) {
wakeup_one((caddr_t)&dead_vnode_wanted);
}
}
/*
* remove the vnode from appropriate free list.
* called with vnode LOCKED and
* the list lock held
*/
static void
vnode_list_remove_locked(vnode_t vp)
{
if (VONLIST(vp)) {
/*
* the v_listflag field is
* protected by the vnode_list_lock
*/
if (vp->v_listflag & VLIST_RAGE) {
VREMRAGE("vnode_list_remove", vp);
} else if (vp->v_listflag & VLIST_DEAD) {
VREMDEAD("vnode_list_remove", vp);
wakeup_laundry_thread();
} else if (vp->v_listflag & VLIST_ASYNC_WORK) {
VREMASYNC_WORK("vnode_list_remove", vp);
} else {
VREMFREE("vnode_list_remove", vp);
}
if (vp->v_flag & VCANDEALLOC) {
os_atomic_inc(&busyvnodes, relaxed);
}
}
}
/*
* remove the vnode from appropriate free list.
* called with vnode LOCKED
*/
static void
vnode_list_remove(vnode_t vp)
{
#if DIAGNOSTIC
lck_mtx_assert(&vp->v_lock, LCK_MTX_ASSERT_OWNED);
#endif
/*
* we want to avoid taking the list lock
* in the case where we're not on the free
* list... this will be true for most
* directories and any currently in use files
*
* we're guaranteed that we can't go from
* the not-on-list state to the on-list
* state since we hold the vnode lock...
* all calls to vnode_list_add are done
* under the vnode lock... so we can
* check for that condition (the prevelant one)
* without taking the list lock
*/
if (VONLIST(vp)) {
vnode_list_lock();
/*
* however, we're not guaranteed that
* we won't go from the on-list state
* to the not-on-list state until we
* hold the vnode_list_lock... this
* is due to "new_vnode" removing vnodes
* from the free list uder the list_lock
* w/o the vnode lock... so we need to
* check again whether we're currently
* on the free list
*/
vnode_list_remove_locked(vp);
vnode_list_unlock();
}
}
void
vnode_rele(vnode_t vp)
{
vnode_rele_internal(vp, 0, 0, 0);
}
void
vnode_rele_ext(vnode_t vp, int fmode, int dont_reenter)
{
vnode_rele_internal(vp, fmode, dont_reenter, 0);
}
void
vnode_rele_internal(vnode_t vp, int fmode, int dont_reenter, int locked)
{
int32_t old_usecount;
if (!locked) {
vnode_hold(vp);
vnode_lock_spin(vp);
}
#if DIAGNOSTIC
else {
lck_mtx_assert(&vp->v_lock, LCK_MTX_ASSERT_OWNED);
}
#endif
/* Enable atomic ops on v_usecount without the vnode lock */
old_usecount = os_atomic_dec_orig(&vp->v_usecount, relaxed);
if (old_usecount < 1) {
/*
* Because we allow atomic ops on usecount (in lookup only, under
* specific conditions of already having a usecount) it is
* possible that when the vnode is examined, its usecount is
* different than what will be printed in this panic message.
*/
panic("vnode_rele_ext: vp %p usecount -ve : %d. v_tag = %d, v_type = %d, v_flag = %x.",
vp, old_usecount - 1, vp->v_tag, vp->v_type, vp->v_flag);
}
if (fmode & FWRITE) {
if (--vp->v_writecount < 0) {
panic("vnode_rele_ext: vp %p writecount -ve : %d. v_tag = %d, v_type = %d, v_flag = %x.", vp, vp->v_writecount, vp->v_tag, vp->v_type, vp->v_flag);
}
}
if (fmode & O_EVTONLY) {
if (--vp->v_kusecount < 0) {
panic("vnode_rele_ext: vp %p kusecount -ve : %d. v_tag = %d, v_type = %d, v_flag = %x.", vp, vp->v_kusecount, vp->v_tag, vp->v_type, vp->v_flag);
}
}
if (vp->v_kusecount > vp->v_usecount) {
panic("vnode_rele_ext: vp %p kusecount(%d) out of balance with usecount(%d). v_tag = %d, v_type = %d, v_flag = %x.", vp, vp->v_kusecount, vp->v_usecount, vp->v_tag, vp->v_type, vp->v_flag);
}
if ((vp->v_iocount > 0) || (vp->v_usecount > 0)) {
/*
* vnode is still busy... if we're the last
* usecount, mark for a future call to VNOP_INACTIVE
* when the iocount finally drops to 0
*/
if (vp->v_usecount == 0) {
vp->v_lflag |= VL_NEEDINACTIVE;
vp->v_flag &= ~(VNOCACHE_DATA | VRAOFF | VOPENEVT);
}
goto done;
}
vp->v_flag &= ~(VNOCACHE_DATA | VRAOFF | VOPENEVT);
if (ISSET(vp->v_lflag, VL_TERMINATE | VL_DEAD) || dont_reenter) {
/*
* vnode is being cleaned, or
* we've requested that we don't reenter
* the filesystem on this release...in
* the latter case, we'll mark the vnode aged
*/
if (dont_reenter) {
if (!(vp->v_lflag & (VL_TERMINATE | VL_DEAD | VL_MARKTERM))) {
vp->v_lflag |= VL_NEEDINACTIVE;
if (vnode_on_reliable_media(vp) == FALSE || vp->v_flag & VISDIRTY) {
vnode_async_list_add(vp);
goto done;
}
}
vp->v_flag |= VAGE;
}
vnode_list_add(vp);
goto done;
}
/*
* at this point both the iocount and usecount
* are zero
* pick up an iocount so that we can call
* VNOP_INACTIVE with the vnode lock unheld
*/
vp->v_iocount++;
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vp->v_lflag &= ~VL_NEEDINACTIVE;
if (UBCINFOEXISTS(vp)) {
ubc_cs_free_and_vnode_unlock(vp);
} else {
vnode_unlock(vp);
}
VNOP_INACTIVE(vp, vfs_context_current());
vnode_lock_spin(vp);
/*
* because we dropped the vnode lock to call VNOP_INACTIVE
* the state of the vnode may have changed... we may have
* picked up an iocount, usecount or the MARKTERM may have
* been set... we need to reevaluate the reference counts
* to determine if we can call vnode_reclaim_internal at
* this point... if the reference counts are up, we'll pick
* up the MARKTERM state when they get subsequently dropped
*/
if ((vp->v_iocount == 1) && (vp->v_usecount == 0) &&
((vp->v_lflag & (VL_MARKTERM | VL_TERMINATE | VL_DEAD)) == VL_MARKTERM)) {
struct uthread *ut;
ut = current_uthread();
if (ut->uu_defer_reclaims) {
vp->v_defer_reclaimlist = ut->uu_vreclaims;
ut->uu_vreclaims = vp;
goto done;
}
vnode_lock_convert(vp);
vnode_reclaim_internal(vp, 1, 1, 0);
}
vnode_dropiocount(vp);
vnode_list_add(vp);
done:
if (vp->v_usecount == 0 && vp->v_type == VREG && !(vp->v_flag & VSYSTEM)) {
if (vp->v_ubcinfo) {
vnode_lock_convert(vp);
memory_object_mark_unused(vp->v_ubcinfo->ui_control, (vp->v_flag & VRAGE) == VRAGE);
}
}
if (!locked) {
vnode_drop_and_unlock(vp);
}
return;
}
/*
* Remove any vnodes in the vnode table belonging to mount point mp.
*
* If MNT_NOFORCE is specified, there should not be any active ones,
* return error if any are found (nb: this is a user error, not a
* system error). If MNT_FORCE is specified, detach any active vnodes
* that are found.
*/
int
vflush(struct mount *mp, struct vnode *skipvp, int flags)
{
struct vnode *vp;
int busy = 0;
int reclaimed = 0;
int retval;
unsigned int vid;
bool first_try = true;
/*
* See comments in vnode_iterate() for the rationale for this lock
*/
mount_iterate_lock(mp);
mount_lock(mp);
vnode_iterate_setup(mp);
/*
* On regular unmounts(not forced) do a
* quick check for vnodes to be in use. This
* preserves the caching of vnodes. automounter
* tries unmounting every so often to see whether
* it is still busy or not.
*/
if (((flags & FORCECLOSE) == 0) && ((mp->mnt_kern_flag & MNTK_UNMOUNT_PREFLIGHT) != 0)) {
if (vnode_umount_preflight(mp, skipvp, flags)) {
vnode_iterate_clear(mp);
mount_unlock(mp);
mount_iterate_unlock(mp);
return EBUSY;
}
}
loop:
/* If it returns 0 then there is nothing to do */
retval = vnode_iterate_prepare(mp);
if (retval == 0) {
vnode_iterate_clear(mp);
mount_unlock(mp);
mount_iterate_unlock(mp);
return retval;
}
/* iterate over all the vnodes */
while (!TAILQ_EMPTY(&mp->mnt_workerqueue)) {
vp = TAILQ_FIRST(&mp->mnt_workerqueue);
TAILQ_REMOVE(&mp->mnt_workerqueue, vp, v_mntvnodes);
TAILQ_INSERT_TAIL(&mp->mnt_vnodelist, vp, v_mntvnodes);
if ((vp->v_mount != mp) || (vp == skipvp)) {
continue;
}
vid = vp->v_id;
mount_unlock(mp);
vnode_lock_spin(vp);
// If vnode is already terminating, wait for it...
while (vp->v_id == vid && ISSET(vp->v_lflag, VL_TERMINATE)) {
vp->v_lflag |= VL_TERMWANT;
msleep(&vp->v_lflag, &vp->v_lock, PVFS, "vflush", NULL);
}
if ((vp->v_id != vid) || ISSET(vp->v_lflag, VL_DEAD)) {
vnode_unlock(vp);
mount_lock(mp);
continue;
}
/*
* If requested, skip over vnodes marked VSYSTEM.
* Skip over all vnodes marked VNOFLUSH.
*/
if ((flags & SKIPSYSTEM) && ((vp->v_flag & VSYSTEM) ||
(vp->v_flag & VNOFLUSH))) {
vnode_unlock(vp);
mount_lock(mp);
continue;
}
/*
* If requested, skip over vnodes marked VSWAP.
*/
if ((flags & SKIPSWAP) && (vp->v_flag & VSWAP)) {
vnode_unlock(vp);
mount_lock(mp);
continue;
}
/*
* If requested, skip over vnodes marked VROOT.
*/
if ((flags & SKIPROOT) && (vp->v_flag & VROOT)) {
vnode_unlock(vp);
mount_lock(mp);
continue;
}
/*
* If WRITECLOSE is set, only flush out regular file
* vnodes open for writing.
*/
if ((flags & WRITECLOSE) &&
(vp->v_writecount == 0 || vp->v_type != VREG)) {
vnode_unlock(vp);
mount_lock(mp);
continue;
}
/*
* If the real usecount is 0, all we need to do is clear
* out the vnode data structures and we are done.
*/
if (((vp->v_usecount == 0) ||
((vp->v_usecount - vp->v_kusecount) == 0))) {
vnode_lock_convert(vp);
vnode_hold(vp);
vp->v_iocount++; /* so that drain waits for * other iocounts */
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_reclaim_internal(vp, 1, 1, 0);
vnode_dropiocount(vp);
vnode_list_add(vp);
vnode_drop_and_unlock(vp);
reclaimed++;
mount_lock(mp);
continue;
}
/*
* If FORCECLOSE is set, forcibly close the vnode.
* For block or character devices, revert to an
* anonymous device. For all other files, just kill them.
*/
if (flags & FORCECLOSE) {
vnode_lock_convert(vp);
if (vp->v_type != VBLK && vp->v_type != VCHR) {
vp->v_iocount++; /* so that drain waits * for other iocounts */
vnode_hold(vp);
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_abort_advlocks(vp);
vnode_reclaim_internal(vp, 1, 1, 0);
vnode_dropiocount(vp);
vnode_list_add(vp);
vnode_drop_and_unlock(vp);
} else {
vnode_hold(vp);
vp->v_lflag |= VL_OPSCHANGE;
vclean(vp, 0);
vp->v_lflag &= ~VL_DEAD;
vp->v_op = spec_vnodeop_p;
vp->v_flag |= VDEVFLUSH;
vnode_drop_and_unlock(vp);
wakeup(&vp->v_lflag); /* chkvnlock is waitng for VL_DEAD to get unset */
}
mount_lock(mp);
continue;
}
/* log vnodes blocking unforced unmounts */
if (print_busy_vnodes && first_try && ((flags & FORCECLOSE) == 0)) {
vprint("vflush - busy vnode", vp);
}
vnode_unlock(vp);
mount_lock(mp);
busy++;
}
/* At this point the worker queue is completed */
if (busy && ((flags & FORCECLOSE) == 0) && reclaimed) {
busy = 0;
reclaimed = 0;
(void)vnode_iterate_reloadq(mp);
first_try = false;
/* returned with mount lock held */
goto loop;
}
/* if new vnodes were created in between retry the reclaim */
if (vnode_iterate_reloadq(mp) != 0) {
if (!(busy && ((flags & FORCECLOSE) == 0))) {
first_try = false;
goto loop;
}
}
vnode_iterate_clear(mp);
mount_unlock(mp);
mount_iterate_unlock(mp);
if (busy && ((flags & FORCECLOSE) == 0)) {
return EBUSY;
}
return 0;
}
long num_recycledvnodes = 0;
/*
* Disassociate the underlying file system from a vnode.
* The vnode lock is held on entry.
*/
static void
vclean(vnode_t vp, int flags)
{
vfs_context_t ctx = vfs_context_current();
int active;
int need_inactive;
int already_terminating;
int clflags = 0;
#if NAMEDSTREAMS
int is_namedstream;
#endif
/*
* Check to see if the vnode is in use.
* If so we have to reference it before we clean it out
* so that its count cannot fall to zero and generate a
* race against ourselves to recycle it.
*/
active = vp->v_usecount;
/*
* just in case we missed sending a needed
* VNOP_INACTIVE, we'll do it now
*/
need_inactive = (vp->v_lflag & VL_NEEDINACTIVE);
vp->v_lflag &= ~VL_NEEDINACTIVE;
/*
* Prevent the vnode from being recycled or
* brought into use while we clean it out.
*/
already_terminating = (vp->v_lflag & VL_TERMINATE);
vp->v_lflag |= VL_TERMINATE;
#if NAMEDSTREAMS
is_namedstream = vnode_isnamedstream(vp);
#endif
vnode_unlock(vp);
OSAddAtomicLong(1, &num_recycledvnodes);
if (flags & DOCLOSE) {
clflags |= IO_NDELAY;
}
if (flags & REVOKEALL) {
clflags |= IO_REVOKE;
}
#if CONFIG_MACF
if (vp->v_mount) {
/*
* It is possible for bdevvp vnodes to not have a mount
* pointer. It's fine to let it get reclaimed without
* notifying.
*/
mac_vnode_notify_reclaim(vp);
}
#endif
if (active && (flags & DOCLOSE)) {
VNOP_CLOSE(vp, clflags, ctx);
}
/*
* Clean out any buffers associated with the vnode.
*/
if (flags & DOCLOSE) {
if (vp->v_tag == VT_NFS) {
nfs_vinvalbuf(vp, V_SAVE, ctx, 0);
} else {
VNOP_FSYNC(vp, MNT_WAIT, ctx);
/*
* If the vnode is still in use (by the journal for
* example) we don't want to invalidate locked buffers
* here. In that case, either the journal will tidy them
* up, or we will deal with it when the usecount is
* finally released in vnode_rele_internal.
*/
buf_invalidateblks(vp, BUF_WRITE_DATA | (active ? 0 : BUF_INVALIDATE_LOCKED), 0, 0);
}
if (UBCINFOEXISTS(vp)) {
/*
* Clean the pages in VM.
*/
(void)ubc_msync(vp, (off_t)0, ubc_getsize(vp), NULL, UBC_PUSHALL | UBC_INVALIDATE | UBC_SYNC);
}
}
if (active || need_inactive) {
VNOP_INACTIVE(vp, ctx);
}
#if NAMEDSTREAMS
if ((is_namedstream != 0) && (vp->v_parent != NULLVP)) {
vnode_t pvp = vp->v_parent;
/* Delete the shadow stream file before we reclaim its vnode */
if (vnode_isshadow(vp)) {
vnode_relenamedstream(pvp, vp);
}
/*
* No more streams associated with the parent. We
* have a ref on it, so its identity is stable.
* If the parent is on an opaque volume, then we need to know
* whether it has associated named streams.
*/
if (vfs_authopaque(pvp->v_mount)) {
vnode_lock_spin(pvp);
pvp->v_lflag &= ~VL_HASSTREAMS;
vnode_unlock(pvp);
}
}
#endif
vm_object_destroy_reason_t reason = VM_OBJECT_DESTROY_UNKNOWN_REASON;
bool forced_unmount = vnode_mount(vp) != NULL && (vnode_mount(vp)->mnt_lflag & MNT_LFORCE) != 0;
bool ungraft_heuristic = flags & REVOKEALL;
if (forced_unmount) {
reason = VM_OBJECT_DESTROY_FORCED_UNMOUNT;
} else if (ungraft_heuristic) {
reason = VM_OBJECT_DESTROY_UNGRAFT;
}
/*
* Destroy ubc named reference
* cluster_release is done on this path
* along with dropping the reference on the ucred
* (and in the case of forced unmount of an mmap-ed file,
* the ubc reference on the vnode is dropped here too).
*/
ubc_destroy_named(vp, reason);
#if CONFIG_TRIGGERS
/*
* cleanup trigger info from vnode (if any)
*/
if (vp->v_resolve) {
vnode_resolver_detach(vp);
}
#endif
#if CONFIG_IO_COMPRESSION_STATS
if ((vp->io_compression_stats)) {
vnode_iocs_record_and_free(vp);
}
#endif /* CONFIG_IO_COMPRESSION_STATS */
/*
* Reclaim the vnode.
*/
if (VNOP_RECLAIM(vp, ctx)) {
panic("vclean: cannot reclaim");
}
// make sure the name & parent ptrs get cleaned out!
vnode_update_identity(vp, NULLVP, NULL, 0, 0, VNODE_UPDATE_PARENT | VNODE_UPDATE_NAME | VNODE_UPDATE_PURGE | VNODE_UPDATE_PURGEFIRMLINK);
vnode_lock(vp);
/*
* Remove the vnode from any mount list it might be on. It is not
* safe to do this any earlier because unmount needs to wait for
* any vnodes to terminate and it cannot do that if it cannot find
* them.
*/
insmntque(vp, (struct mount *)0);
vp->v_lflag |= VL_DEAD;
vp->v_mount = dead_mountp;
vp->v_op = dead_vnodeop_p;
vp->v_tag = VT_NON;
vp->v_data = NULL;
vp->v_flag &= ~VISDIRTY;
if (already_terminating == 0) {
vp->v_lflag &= ~VL_TERMINATE;
/*
* Done with purge, notify sleepers of the grim news.
*/
if (vp->v_lflag & VL_TERMWANT) {
vp->v_lflag &= ~VL_TERMWANT;
wakeup(&vp->v_lflag);
}
}
}
/*
* Eliminate all activity associated with the requested vnode
* and with all vnodes aliased to the requested vnode.
*/
int
#if DIAGNOSTIC
vn_revoke(vnode_t vp, int flags, __unused vfs_context_t a_context)
#else
vn_revoke(vnode_t vp, __unused int flags, __unused vfs_context_t a_context)
#endif
{
struct vnode *vq;
int vid;
#if DIAGNOSTIC
if ((flags & REVOKEALL) == 0) {
panic("vnop_revoke");
}
#endif
if (vnode_isaliased(vp)) {
/*
* If a vgone (or vclean) is already in progress,
* return an immediate error
*/
if (vp->v_lflag & VL_TERMINATE) {
return ENOENT;
}
/*
* Ensure that vp will not be vgone'd while we
* are eliminating its aliases.
*/
SPECHASH_LOCK();
while ((vp->v_specflags & SI_ALIASED)) {
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type || vp == vq) {
continue;
}
vid = vq->v_id;
vnode_hold(vq);
SPECHASH_UNLOCK();
if (vnode_getwithvid(vq, vid)) {
vq = vnode_drop(vq);
SPECHASH_LOCK();
break;
}
vnode_lock(vq);
if (!(vq->v_lflag & VL_TERMINATE)) {
vnode_reclaim_internal(vq, 1, 1, 0);
}
vnode_put_locked(vq);
vq = vnode_drop_and_unlock(vq);
SPECHASH_LOCK();
break;
}
}
SPECHASH_UNLOCK();
}
vnode_lock(vp);
if (vp->v_lflag & VL_TERMINATE) {
vnode_unlock(vp);
return ENOENT;
}
vnode_reclaim_internal(vp, 1, 0, REVOKEALL);
vnode_unlock(vp);
return 0;
}
/*
* Recycle an unused vnode to the front of the free list.
* Release the passed interlock if the vnode will be recycled.
*/
int
vnode_recycle(struct vnode *vp)
{
vnode_lock_spin(vp);
if (vp->v_iocount || vp->v_usecount) {
vp->v_lflag |= VL_MARKTERM;
vnode_unlock(vp);
return 0;
}
vnode_lock_convert(vp);
vnode_hold(vp);
vnode_reclaim_internal(vp, 1, 0, 0);
vnode_drop_and_unlock(vp);
return 1;
}
static int
vnode_reload(vnode_t vp)
{
vnode_lock_spin(vp);
if ((vp->v_iocount > 1) || vp->v_usecount) {
vnode_unlock(vp);
return 0;
}
if (vp->v_iocount <= 0) {
panic("vnode_reload with no iocount %d", vp->v_iocount);
}
/* mark for release when iocount is dopped */
vp->v_lflag |= VL_MARKTERM;
vnode_unlock(vp);
return 1;
}
static void
vgone(vnode_t vp, int flags)
{
struct vnode *vq;
struct vnode *vx;
/*
* Clean out the filesystem specific data.
* vclean also takes care of removing the
* vnode from any mount list it might be on
*/
vclean(vp, flags | DOCLOSE);
/*
* If special device, remove it from special device alias list
* if it is on one.
*/
if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_specinfo != 0) {
SPECHASH_LOCK();
if (*vp->v_hashchain == vp) {
*vp->v_hashchain = vp->v_specnext;
} else {
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_specnext != vp) {
continue;
}
vq->v_specnext = vp->v_specnext;
break;
}
if (vq == NULL) {
panic("missing bdev");
}
}
if (vp->v_specflags & SI_ALIASED) {
vx = NULL;
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type) {
continue;
}
if (vx) {
break;
}
vx = vq;
}
if (vx == NULL) {
panic("missing alias");
}
if (vq == NULL) {
vx->v_specflags &= ~SI_ALIASED;
}
vp->v_specflags &= ~SI_ALIASED;
}
SPECHASH_UNLOCK();
{
struct specinfo *tmp = vp->v_specinfo;
vp->v_specinfo = NULL;
zfree(specinfo_zone, tmp);
}
}
}
/*
* Lookup a vnode by device number.
*/
int
check_mountedon(dev_t dev, enum vtype type, int *errorp)
{
vnode_t vp;
int rc = 0;
int vid;
loop:
SPECHASH_LOCK();
for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) {
if (dev != vp->v_rdev || type != vp->v_type) {
continue;
}
vid = vp->v_id;
vnode_hold(vp);
SPECHASH_UNLOCK();
if (vnode_getwithvid(vp, vid)) {
vnode_drop(vp);
goto loop;
}
vnode_drop(vp);
vnode_lock_spin(vp);
if ((vp->v_usecount > 0) || (vp->v_iocount > 1)) {
vnode_unlock(vp);
if ((*errorp = vfs_mountedon(vp)) != 0) {
rc = 1;
}
} else {
vnode_unlock(vp);
}
vnode_put(vp);
return rc;
}
SPECHASH_UNLOCK();
return 0;
}
/*
* Calculate the total number of references to a special device.
*/
int
vcount(vnode_t vp)
{
vnode_t vq, vnext;
int count;
int vid;
if (!vnode_isspec(vp)) {
return vp->v_usecount - vp->v_kusecount;
}
loop:
if (!vnode_isaliased(vp)) {
return vp->v_specinfo->si_opencount;
}
count = 0;
SPECHASH_LOCK();
/*
* Grab first vnode and its vid.
*/
vq = *vp->v_hashchain;
if (vq) {
vid = vq->v_id;
vnode_hold(vq);
} else {
vid = 0;
}
SPECHASH_UNLOCK();
while (vq) {
/*
* Attempt to get the vnode outside the SPECHASH lock.
* Don't take iocount on 'vp' as iocount is already held by the caller.
*/
if ((vq != vp) && vnode_getwithvid(vq, vid)) {
vnode_drop(vq);
goto loop;
}
vnode_drop(vq);
vnode_lock(vq);
if (vq->v_rdev == vp->v_rdev && vq->v_type == vp->v_type) {
if ((vq->v_usecount == 0) && (vq->v_iocount == 1) && vq != vp) {
/*
* Alias, but not in use, so flush it out.
*/
vnode_hold(vq);
vnode_reclaim_internal(vq, 1, 1, 0);
vnode_put_locked(vq);
vnode_drop_and_unlock(vq);
goto loop;
}
count += vq->v_specinfo->si_opencount;
}
vnode_unlock(vq);
SPECHASH_LOCK();
/*
* must do this with the reference still held on 'vq'
* so that it can't be destroyed while we're poking
* through v_specnext
*/
vnext = vq->v_specnext;
if (vnext) {
vid = vnext->v_id;
vnode_hold(vnext);
} else {
vid = 0;
}
SPECHASH_UNLOCK();
if (vq != vp) {
vnode_put(vq);
}
vq = vnext;
}
return count;
}
int prtactive = 0; /* 1 => print out reclaim of active vnodes */
/*
* Print out a description of a vnode.
*/
static const char *typename[] =
{ "VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD" };
void
vprint(const char *label, struct vnode *vp)
{
char sbuf[64];
if (label != NULL) {
printf("%s: ", label);
}
printf("name %s type %s, usecount %d, writecount %d\n",
vp->v_name, typename[vp->v_type],
vp->v_usecount, vp->v_writecount);
sbuf[0] = '\0';
if (vp->v_flag & VROOT) {
strlcat(sbuf, "|VROOT", sizeof(sbuf));
}
if (vp->v_flag & VTEXT) {
strlcat(sbuf, "|VTEXT", sizeof(sbuf));
}
if (vp->v_flag & VSYSTEM) {
strlcat(sbuf, "|VSYSTEM", sizeof(sbuf));
}
if (vp->v_flag & VNOFLUSH) {
strlcat(sbuf, "|VNOFLUSH", sizeof(sbuf));
}
if (vp->v_flag & VBWAIT) {
strlcat(sbuf, "|VBWAIT", sizeof(sbuf));
}
if (vnode_isaliased(vp)) {
strlcat(sbuf, "|VALIASED", sizeof(sbuf));
}
if (sbuf[0] != '\0') {
printf("vnode flags (%s\n", &sbuf[1]);
}
}
static int
vn_getpath_flags_to_buildpath_flags(int flags)
{
int bpflags = (flags & VN_GETPATH_FSENTER) ? 0 : BUILDPATH_NO_FS_ENTER;
if (flags && (flags != VN_GETPATH_FSENTER)) {
if (flags & VN_GETPATH_NO_FIRMLINK) {
bpflags |= BUILDPATH_NO_FIRMLINK;
}
if (flags & VN_GETPATH_VOLUME_RELATIVE) {
bpflags |= (BUILDPATH_VOLUME_RELATIVE |
BUILDPATH_NO_FIRMLINK);
}
if (flags & VN_GETPATH_NO_PROCROOT) {
bpflags |= BUILDPATH_NO_PROCROOT;
}
if (flags & VN_GETPATH_CHECK_MOVED) {
bpflags |= BUILDPATH_CHECK_MOVED;
}
}
return bpflags;
}
int
vn_getpath_ext_with_mntlen(struct vnode *vp, struct vnode *dvp, char *pathbuf,
size_t *len, size_t *mntlen, int flags)
{
int bpflags = vn_getpath_flags_to_buildpath_flags(flags);
int local_len;
int error;
if (*len > INT_MAX) {
return EINVAL;
}
local_len = *len;
error = build_path_with_parent(vp, dvp, pathbuf, local_len, &local_len,
mntlen, bpflags, vfs_context_current());
if (local_len >= 0 && local_len <= (int)*len) {
*len = (size_t)local_len;
}
return error;
}
int
vn_getpath_ext(struct vnode *vp, struct vnode *dvp, char *pathbuf, size_t *len,
int flags)
{
return vn_getpath_ext_with_mntlen(vp, dvp, pathbuf, len, NULL, flags);
}
/*
* Wrapper around vn_getpath_ext() that takes care of the int * <-> size_t *
* conversion for the legacy KPIs.
*/
static int
vn_getpath_ext_int(struct vnode *vp, struct vnode *dvp, char *pathbuf,
int *len, int flags)
{
size_t slen = *len;
int error;
if (*len < 0) {
return EINVAL;
}
error = vn_getpath_ext(vp, dvp, pathbuf, &slen, flags);
if (slen <= INT_MAX) {
*len = (int)slen;
}
return error;
}
int
vn_getpath(struct vnode *vp, char *pathbuf, int *len)
{
return vn_getpath_ext_int(vp, NULL, pathbuf, len, 0);
}
int
vn_getpath_fsenter(struct vnode *vp, char *pathbuf, int *len)
{
return vn_getpath_ext_int(vp, NULL, pathbuf, len, VN_GETPATH_FSENTER);
}
/*
* vn_getpath_fsenter_with_parent will reenter the file system to fine the path of the
* vnode. It requires that there are IO counts on both the vnode and the directory vnode.
*
* vn_getpath_fsenter is called by MAC hooks to authorize operations for every thing, but
* unlink, rmdir and rename. For these operation the MAC hook calls vn_getpath. This presents
* problems where if the path can not be found from the name cache, those operations can
* erroneously fail with EPERM even though the call should succeed. When removing or moving
* file system objects with operations such as unlink or rename, those operations need to
* take IO counts on the target and containing directory. Calling vn_getpath_fsenter from a
* MAC hook from these operations during forced unmount operations can lead to dead
* lock. This happens when the operation starts, IO counts are taken on the containing
* directories and targets. Before the MAC hook is called a forced unmount from another
* thread takes place and blocks on the on going operation's directory vnode in vdrain.
* After which, the MAC hook gets called and calls vn_getpath_fsenter. vn_getpath_fsenter
* is called with the understanding that there is an IO count on the target. If in
* build_path the directory vnode is no longer in the cache, then the parent object id via
* vnode_getattr from the target is obtain and used to call VFS_VGET to get the parent
* vnode. The file system's VFS_VGET then looks up by inode in its hash and tries to get
* an IO count. But VFS_VGET "sees" the directory vnode is in vdrain and can block
* depending on which version and how it calls the vnode_get family of interfaces.
*
* N.B. A reasonable interface to use is vnode_getwithvid. This interface was modified to
* call vnode_getiocount with VNODE_DRAINO, so it will happily get an IO count and not
* cause issues, but there is no guarantee that all or any file systems are doing that.
*
* vn_getpath_fsenter_with_parent can enter the file system safely since there is a known
* IO count on the directory vnode by calling build_path_with_parent.
*/
int
vn_getpath_fsenter_with_parent(struct vnode *dvp, struct vnode *vp, char *pathbuf, int *len)
{
return build_path_with_parent(vp, dvp, pathbuf, *len, len, NULL, 0, vfs_context_current());
}
int
vn_getpath_no_firmlink(struct vnode *vp, char *pathbuf, int *len)
{
return vn_getpath_ext_int(vp, NULLVP, pathbuf, len,
VN_GETPATH_NO_FIRMLINK);
}
int
vn_getcdhash(struct vnode *vp, off_t offset, unsigned char *cdhash)
{
return ubc_cs_getcdhash(vp, offset, cdhash);
}
static char *extension_table = NULL;
static int nexts;
static int max_ext_width;
static int
extension_cmp(const void *a, const void *b)
{
return (int)(strlen((const char *)a) - strlen((const char *)b));
}
//
// This is the api LaunchServices uses to inform the kernel
// the list of package extensions to ignore.
//
// Internally we keep the list sorted by the length of the
// the extension (from longest to shortest). We sort the
// list of extensions so that we can speed up our searches
// when comparing file names -- we only compare extensions
// that could possibly fit into the file name, not all of
// them (i.e. a short 8 character name can't have an 8
// character extension).
//
extern lck_mtx_t pkg_extensions_lck;
__private_extern__ int
set_package_extensions_table(user_addr_t data, int nentries, int maxwidth)
{
char *new_exts, *old_exts;
int old_nentries = 0, old_maxwidth = 0;
int error;
if (nentries <= 0 || nentries > 1024 || maxwidth <= 0 || maxwidth > 255) {
return EINVAL;
}
// allocate one byte extra so we can guarantee null termination
new_exts = kalloc_data((nentries * maxwidth) + 1, Z_WAITOK);
if (new_exts == NULL) {
return ENOMEM;
}
error = copyin(data, new_exts, nentries * maxwidth);
if (error) {
kfree_data(new_exts, (nentries * maxwidth) + 1);
return error;
}
new_exts[(nentries * maxwidth)] = '\0'; // guarantee null termination of the block
qsort(new_exts, nentries, maxwidth, extension_cmp);
lck_mtx_lock(&pkg_extensions_lck);
old_exts = extension_table;
old_nentries = nexts;
old_maxwidth = max_ext_width;
extension_table = new_exts;
nexts = nentries;
max_ext_width = maxwidth;
lck_mtx_unlock(&pkg_extensions_lck);
kfree_data(old_exts, (old_nentries * old_maxwidth) + 1);
return 0;
}
int
is_package_name(const char *name, int len)
{
int i;
size_t extlen;
const char *ptr, *name_ext;
// if the name is less than 3 bytes it can't be of the
// form A.B and if it begins with a "." then it is also
// not a package.
if (len <= 3 || name[0] == '.') {
return 0;
}
name_ext = NULL;
for (ptr = name; *ptr != '\0'; ptr++) {
if (*ptr == '.') {
name_ext = ptr;
}
}
// if there is no "." extension, it can't match
if (name_ext == NULL) {
return 0;
}
// advance over the "."
name_ext++;
lck_mtx_lock(&pkg_extensions_lck);
// now iterate over all the extensions to see if any match
ptr = &extension_table[0];
for (i = 0; i < nexts; i++, ptr += max_ext_width) {
extlen = strlen(ptr);
if (strncasecmp(name_ext, ptr, extlen) == 0 && name_ext[extlen] == '\0') {
// aha, a match!
lck_mtx_unlock(&pkg_extensions_lck);
return 1;
}
}
lck_mtx_unlock(&pkg_extensions_lck);
// if we get here, no extension matched
return 0;
}
int
vn_path_package_check(__unused vnode_t vp, char *path, int pathlen, int *component)
{
char *ptr, *end;
int comp = 0;
if (pathlen < 0) {
return EINVAL;
}
*component = -1;
if (*path != '/') {
return EINVAL;
}
end = path + 1;
while (end < path + pathlen && *end != '\0') {
while (end < path + pathlen && *end == '/' && *end != '\0') {
end++;
}
ptr = end;
while (end < path + pathlen && *end != '/' && *end != '\0') {
end++;
}
if (end > path + pathlen) {
// hmm, string wasn't null terminated
return EINVAL;
}
*end = '\0';
if (is_package_name(ptr, (int)(end - ptr))) {
*component = comp;
break;
}
end++;
comp++;
}
return 0;
}
/*
* Determine if a name is inappropriate for a searchfs query.
* This list consists of /System currently.
*/
int
vn_searchfs_inappropriate_name(const char *name, int len)
{
const char *bad_names[] = { "System" };
int bad_len[] = { 6 };
int i;
if (len < 0) {
return EINVAL;
}
for (i = 0; i < (int) (sizeof(bad_names) / sizeof(bad_names[0])); i++) {
if (len == bad_len[i] && strncmp(name, bad_names[i], strlen(bad_names[i]) + 1) == 0) {
return 1;
}
}
// if we get here, no name matched
return 0;
}
/*
* Top level filesystem related information gathering.
*/
extern unsigned int vfs_nummntops;
/*
* The VFS_NUMMNTOPS shouldn't be at name[1] since
* is a VFS generic variable. Since we no longer support
* VT_UFS, we reserve its value to support this sysctl node.
*
* It should have been:
* name[0]: VFS_GENERIC
* name[1]: VFS_NUMMNTOPS
*/
SYSCTL_INT(_vfs, VFS_NUMMNTOPS, nummntops,
CTLFLAG_RD | CTLFLAG_KERN | CTLFLAG_LOCKED,
&vfs_nummntops, 0, "");
int
vfs_sysctl(int *name __unused, u_int namelen __unused,
user_addr_t oldp __unused, size_t *oldlenp __unused,
user_addr_t newp __unused, size_t newlen __unused, proc_t p __unused);
int
vfs_sysctl(int *name __unused, u_int namelen __unused,
user_addr_t oldp __unused, size_t *oldlenp __unused,
user_addr_t newp __unused, size_t newlen __unused, proc_t p __unused)
{
return EINVAL;
}
//
// The following code disallows specific sysctl's that came through
// the direct sysctl interface (vfs_sysctl_node) instead of the newer
// sysctl_vfs_ctlbyfsid() interface. We can not allow these selectors
// through vfs_sysctl_node() because it passes the user's oldp pointer
// directly to the file system which (for these selectors) casts it
// back to a struct sysctl_req and then proceed to use SYSCTL_IN()
// which jumps through an arbitrary function pointer. When called
// through the sysctl_vfs_ctlbyfsid() interface this does not happen
// and so it's safe.
//
// Unfortunately we have to pull in definitions from AFP and SMB and
// perform explicit name checks on the file system to determine if
// these selectors are being used.
//
#define AFPFS_VFS_CTL_GETID 0x00020001
#define AFPFS_VFS_CTL_NETCHANGE 0x00020002
#define AFPFS_VFS_CTL_VOLCHANGE 0x00020003
#define SMBFS_SYSCTL_REMOUNT 1
#define SMBFS_SYSCTL_REMOUNT_INFO 2
#define SMBFS_SYSCTL_GET_SERVER_SHARE 3
static int
is_bad_sysctl_name(struct vfstable *vfsp, int selector_name)
{
switch (selector_name) {
case VFS_CTL_QUERY:
case VFS_CTL_TIMEO:
case VFS_CTL_NOLOCKS:
case VFS_CTL_NSTATUS:
case VFS_CTL_SADDR:
case VFS_CTL_DISC:
case VFS_CTL_SERVERINFO:
return 1;
default:
break;
}
// the more complicated check for some of SMB's special values
if (strcmp(vfsp->vfc_name, "smbfs") == 0) {
switch (selector_name) {
case SMBFS_SYSCTL_REMOUNT:
case SMBFS_SYSCTL_REMOUNT_INFO:
case SMBFS_SYSCTL_GET_SERVER_SHARE:
return 1;
}
} else if (strcmp(vfsp->vfc_name, "afpfs") == 0) {
switch (selector_name) {
case AFPFS_VFS_CTL_GETID:
case AFPFS_VFS_CTL_NETCHANGE:
case AFPFS_VFS_CTL_VOLCHANGE:
return 1;
}
}
//
// If we get here we passed all the checks so the selector is ok
//
return 0;
}
int vfs_sysctl_node SYSCTL_HANDLER_ARGS
{
int *name, namelen;
struct vfstable *vfsp;
int error;
int fstypenum;
fstypenum = oidp->oid_number;
name = arg1;
namelen = arg2;
/* all sysctl names at this level should have at least one name slot for the FS */
if (namelen < 1) {
return EISDIR; /* overloaded */
}
mount_list_lock();
for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
if (vfsp->vfc_typenum == fstypenum) {
vfsp->vfc_refcount++;
break;
}
}
mount_list_unlock();
if (vfsp == NULL) {
return ENOTSUP;
}
if (is_bad_sysctl_name(vfsp, name[0])) {
printf("vfs: bad selector 0x%.8x for old-style sysctl(). use the sysctl-by-fsid interface instead\n", name[0]);
error = EPERM;
} else {
error = (vfsp->vfc_vfsops->vfs_sysctl)(name, namelen,
req->oldptr, &req->oldlen, req->newptr, req->newlen,
vfs_context_current());
}
mount_list_lock();
vfsp->vfc_refcount--;
mount_list_unlock();
return error;
}
/*
* Check to see if a filesystem is mounted on a block device.
*/
int
vfs_mountedon(struct vnode *vp)
{
struct vnode *vq;
int error = 0;
restart:
SPECHASH_LOCK();
if (vp->v_specflags & SI_MOUNTING && (vp->v_specinfo->si_mountingowner != current_thread())) {
msleep((caddr_t)&vp->v_specflags, SPECHASH_LOCK_ADDR(), PVFS | PDROP, "vnode_waitformounting", NULL);
goto restart;
}
if (vp->v_specflags & SI_MOUNTEDON) {
error = EBUSY;
goto out;
}
if (vp->v_specflags & SI_ALIASED) {
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type) {
continue;
}
if (vq->v_specflags & SI_MOUNTING) {
msleep((caddr_t)&vq->v_specflags, SPECHASH_LOCK_ADDR(), PVFS | PDROP, "vnode_waitformounting", NULL);
goto restart;
}
if (vq->v_specflags & SI_MOUNTEDON) {
error = EBUSY;
break;
}
}
}
out:
SPECHASH_UNLOCK();
return error;
}
void
vfs_setmountedon(vnode_t vp)
{
vnode_lock(vp);
SPECHASH_LOCK();
vp->v_specflags |= SI_MOUNTEDON;
vp->v_specflags &= ~SI_MOUNTING;
vp->v_specinfo->si_mountingowner = NULL;
SPECHASH_UNLOCK();
vnode_unlock(vp);
wakeup(&vp->v_specflags);
}
void
vfs_clearmounting(vnode_t vp)
{
vnode_lock(vp);
SPECHASH_LOCK();
vp->v_specflags &= ~SI_MOUNTING;
vp->v_specinfo->si_mountingowner = NULL;
SPECHASH_UNLOCK();
vnode_unlock(vp);
wakeup(&vp->v_specflags);
}
/*
* Check to see if a filesystem is mounted on a block device.
*/
int
vfs_setmounting(vnode_t vp)
{
struct vnode *vq;
int error = 0;
vnode_lock(vp);
while (vp->v_specflags & SI_MOUNTING) {
msleep((caddr_t)&vp->v_specflags, &vp->v_lock, PVFS, "vnode_waitformounting", NULL);
}
if (vp->v_specflags & SI_MOUNTEDON) {
vnode_unlock(vp);
return EBUSY;
}
SPECHASH_LOCK();
vp->v_specflags |= SI_MOUNTING;
vp->v_specinfo->si_mountingowner = current_thread();
vnode_unlock(vp);
restart:
if (vp->v_specflags & SI_ALIASED) {
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type || vq == vp) {
continue;
}
if (vq->v_specflags & SI_MOUNTING) {
msleep((caddr_t)&vq->v_specflags, SPECHASH_LOCK_ADDR(), PVFS | PDROP, "vnode_waitformounting", NULL);
SPECHASH_LOCK();
goto restart;
}
if (vq->v_specflags & SI_MOUNTEDON) {
error = EBUSY;
break;
}
}
}
SPECHASH_UNLOCK();
if (error) {
vnode_lock(vp);
SPECHASH_LOCK();
vp->v_specflags &= ~SI_MOUNTING;
SPECHASH_UNLOCK();
vnode_unlock(vp);
wakeup(&vp->v_specflags);
}
return error;
}
struct unmount_info {
int u_errs; // Total failed unmounts
int u_busy; // EBUSY failed unmounts
int u_count; // Total volumes iterated
int u_only_non_system;
};
static int
unmount_callback(mount_t mp, void *arg)
{
int error;
char *mntname;
struct unmount_info *uip = arg;
uip->u_count++;
mntname = zalloc_flags(ZV_NAMEI, Z_WAITOK | Z_NOFAIL);
strlcpy(mntname, mp->mnt_vfsstat.f_mntonname, MAXPATHLEN);
if (uip->u_only_non_system
&& ((mp->mnt_flag & MNT_ROOTFS) || (mp->mnt_kern_flag & MNTK_SYSTEM))) { //MNTK_BACKS_ROOT
printf("unmount(%d) %s skipped\n", uip->u_only_non_system, mntname);
mount_iterdrop(mp); // VFS_ITERATE_CB_DROPREF
} else {
printf("unmount(%d) %s\n", uip->u_only_non_system, mntname);
mount_ref(mp, 0);
mount_iterdrop(mp); // VFS_ITERATE_CB_DROPREF
error = dounmount(mp, MNT_FORCE, 1, vfs_context_current());
if (error) {
uip->u_errs++;
printf("Unmount of %s failed (%d)\n", mntname ? mntname:"?", error);
if (error == EBUSY) {
uip->u_busy++;
}
}
}
zfree(ZV_NAMEI, mntname);
return VFS_RETURNED;
}
/*
* Unmount all filesystems. The list is traversed in reverse order
* of mounting to avoid dependencies.
* Busy mounts are retried.
*/
__private_extern__ void
vfs_unmountall(int only_non_system)
{
int mounts, sec = 1;
struct unmount_info ui;
/*
* Ensure last-completion-time is valid before anyone can see that
* VFS shutdown has started.
*/
vfs_shutdown_last_completion_time = mach_absolute_time();
OSMemoryBarrier();
vfs_unmountall_started = 1;
printf("vfs_unmountall(%ssystem) start\n", only_non_system ? "non" : "");
retry:
ui.u_errs = ui.u_busy = ui.u_count = 0;
ui.u_only_non_system = only_non_system;
// avoid vfs_iterate deadlock in dounmount(), use VFS_ITERATE_CB_DROPREF
vfs_iterate(VFS_ITERATE_CB_DROPREF | VFS_ITERATE_TAIL_FIRST, unmount_callback, &ui);
mounts = mount_getvfscnt();
if (mounts == 0) {
goto out;
}
if (ui.u_busy > 0) { // Busy mounts - wait & retry
tsleep(&nummounts, PVFS, "busy mount", sec * hz);
sec *= 2;
if (sec <= 32) {
goto retry;
}
printf("Unmounting timed out\n");
} else if (ui.u_count < mounts) {
// If the vfs_iterate missed mounts in progress - wait a bit
tsleep(&nummounts, PVFS, "missed mount", 2 * hz);
}
out:
printf("vfs_unmountall(%ssystem) end\n", only_non_system ? "non" : "");
/*
* reboot_kernel() calls us twice; once to deal with non-system
* mounts, and again to sweep up anything left after terminating
* DEXTs. We're only finished once we've completed the second pass.
*/
if (!only_non_system) {
vfs_unmountall_finished = 1;
}
}
/*
* vfs_shutdown_in_progress --
*
* Returns whether or not the VFS is shutting down the file systems.
*/
boolean_t
vfs_shutdown_in_progress(void)
{
return vfs_unmountall_started && !vfs_unmountall_finished;
}
/*
* vfs_shutdown_finished --
*
* Returns whether or not the VFS shutdown has completed.
*/
boolean_t
vfs_shutdown_finished(void)
{
return !!vfs_unmountall_finished;
}
/*
* vfs_update_last_completion_time --
*
* Updates the "last I/O completion time" timestamp used by the watchdog
* to monitor VFS shutdown progress. Called by various I/O stack layers
* as operations complete and progress moves forward.
*/
void
vfs_update_last_completion_time(void)
{
if (vfs_unmountall_started) {
vfs_shutdown_last_completion_time = mach_absolute_time();
}
}
/*
* vfs_last_completion_time --
*
* Returns the "last I/O completion time" timestamp. Return
* value is a mach_absolute_time() value, and is not meaningful
* unless vfs_is_shutting_down() also returns true.
*/
uint64_t
vfs_last_completion_time(void)
{
return vfs_unmountall_started ? vfs_shutdown_last_completion_time : 0;
}
/*
* This routine is called from vnode_pager_deallocate out of the VM
* The path to vnode_pager_deallocate can only be initiated by ubc_destroy_named
* on a vnode that has a UBCINFO
*/
__private_extern__ void
vnode_pager_vrele(vnode_t vp)
{
struct ubc_info *uip;
vnode_lock_spin(vp);
vp->v_lflag &= ~VNAMED_UBC;
if (vp->v_usecount != 0) {
/*
* At the eleventh hour, just before the ubcinfo is
* destroyed, ensure the ubc-specific v_usecount
* reference has gone. We use v_usecount != 0 as a hint;
* ubc_unmap() does nothing if there's no mapping.
*
* This case is caused by coming here via forced unmount,
* versus the usual vm_object_deallocate() path.
* In the forced unmount case, ubc_destroy_named()
* releases the pager before memory_object_last_unmap()
* can be called.
*/
vnode_unlock(vp);
ubc_unmap(vp);
vnode_lock_spin(vp);
}
uip = vp->v_ubcinfo;
vp->v_ubcinfo = UBC_INFO_NULL;
vnode_unlock(vp);
ubc_info_deallocate(uip);
}
#include <sys/disk.h>
u_int32_t rootunit = (u_int32_t)-1;
#if CONFIG_IOSCHED
extern int lowpri_throttle_enabled;
extern int iosched_enabled;
#endif
errno_t
vfs_init_io_attributes(vnode_t devvp, mount_t mp)
{
int error;
off_t readblockcnt = 0;
off_t writeblockcnt = 0;
off_t readmaxcnt = 0;
off_t writemaxcnt = 0;
off_t readsegcnt = 0;
off_t writesegcnt = 0;
off_t readsegsize = 0;
off_t writesegsize = 0;
off_t alignment = 0;
u_int32_t minsaturationbytecount = 0;
u_int32_t ioqueue_depth = 0;
u_int32_t blksize;
u_int64_t temp;
u_int32_t features;
u_int64_t location = 0;
vfs_context_t ctx = vfs_context_current();
dk_corestorage_info_t cs_info;
boolean_t cs_present = FALSE;
int isssd = 0;
int isvirtual = 0;
VNOP_IOCTL(devvp, DKIOCGETTHROTTLEMASK, (caddr_t)&mp->mnt_throttle_mask, 0, NULL);
/*
* as a reasonable approximation, only use the lowest bit of the mask
* to generate a disk unit number
*/
mp->mnt_devbsdunit = num_trailing_0(mp->mnt_throttle_mask);
if (devvp == rootvp) {
rootunit = mp->mnt_devbsdunit;
}
if (mp->mnt_devbsdunit == rootunit) {
/*
* this mount point exists on the same device as the root
* partition, so it comes under the hard throttle control...
* this is true even for the root mount point itself
*/
mp->mnt_kern_flag |= MNTK_ROOTDEV;
}
/*
* force the spec device to re-cache
* the underlying block size in case
* the filesystem overrode the initial value
*/
set_fsblocksize(devvp);
if ((error = VNOP_IOCTL(devvp, DKIOCGETBLOCKSIZE,
(caddr_t)&blksize, 0, ctx))) {
return error;
}
mp->mnt_devblocksize = blksize;
/*
* set the maximum possible I/O size
* this may get clipped to a smaller value
* based on which constraints are being advertised
* and if those advertised constraints result in a smaller
* limit for a given I/O
*/
mp->mnt_maxreadcnt = MAX_UPL_SIZE_BYTES;
mp->mnt_maxwritecnt = MAX_UPL_SIZE_BYTES;
if (VNOP_IOCTL(devvp, DKIOCISVIRTUAL, (caddr_t)&isvirtual, 0, ctx) == 0) {
if (isvirtual) {
mp->mnt_kern_flag |= MNTK_VIRTUALDEV;
mp->mnt_flag |= MNT_REMOVABLE;
}
}
if (VNOP_IOCTL(devvp, DKIOCISSOLIDSTATE, (caddr_t)&isssd, 0, ctx) == 0) {
if (isssd) {
mp->mnt_kern_flag |= MNTK_SSD;
}
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETFEATURES,
(caddr_t)&features, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXBLOCKCOUNTREAD,
(caddr_t)&readblockcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXBLOCKCOUNTWRITE,
(caddr_t)&writeblockcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXBYTECOUNTREAD,
(caddr_t)&readmaxcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXBYTECOUNTWRITE,
(caddr_t)&writemaxcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXSEGMENTCOUNTREAD,
(caddr_t)&readsegcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXSEGMENTCOUNTWRITE,
(caddr_t)&writesegcnt, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXSEGMENTBYTECOUNTREAD,
(caddr_t)&readsegsize, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMAXSEGMENTBYTECOUNTWRITE,
(caddr_t)&writesegsize, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETMINSEGMENTALIGNMENTBYTECOUNT,
(caddr_t)&alignment, 0, ctx))) {
return error;
}
if ((error = VNOP_IOCTL(devvp, DKIOCGETCOMMANDPOOLSIZE,
(caddr_t)&ioqueue_depth, 0, ctx))) {
return error;
}
if (readmaxcnt) {
mp->mnt_maxreadcnt = (readmaxcnt > UINT32_MAX) ? UINT32_MAX :(uint32_t) readmaxcnt;
}
if (readblockcnt) {
temp = readblockcnt * blksize;
temp = (temp > UINT32_MAX) ? UINT32_MAX : temp;
if (temp < mp->mnt_maxreadcnt) {
mp->mnt_maxreadcnt = (u_int32_t)temp;
}
}
if (writemaxcnt) {
mp->mnt_maxwritecnt = (writemaxcnt > UINT32_MAX) ? UINT32_MAX : (uint32_t)writemaxcnt;
}
if (writeblockcnt) {
temp = writeblockcnt * blksize;
temp = (temp > UINT32_MAX) ? UINT32_MAX : temp;
if (temp < mp->mnt_maxwritecnt) {
mp->mnt_maxwritecnt = (u_int32_t)temp;
}
}
if (readsegcnt) {
temp = (readsegcnt > UINT16_MAX) ? UINT16_MAX : readsegcnt;
} else {
temp = mp->mnt_maxreadcnt / PAGE_SIZE;
if (temp > UINT16_MAX) {
temp = UINT16_MAX;
}
}
mp->mnt_segreadcnt = (u_int16_t)temp;
if (writesegcnt) {
temp = (writesegcnt > UINT16_MAX) ? UINT16_MAX : writesegcnt;
} else {
temp = mp->mnt_maxwritecnt / PAGE_SIZE;
if (temp > UINT16_MAX) {
temp = UINT16_MAX;
}
}
mp->mnt_segwritecnt = (u_int16_t)temp;
if (readsegsize) {
temp = (readsegsize > UINT32_MAX) ? UINT32_MAX : readsegsize;
} else {
temp = mp->mnt_maxreadcnt;
}
mp->mnt_maxsegreadsize = (u_int32_t)temp;
if (writesegsize) {
temp = (writesegsize > UINT32_MAX) ? UINT32_MAX : writesegsize;
} else {
temp = mp->mnt_maxwritecnt;
}
mp->mnt_maxsegwritesize = (u_int32_t)temp;
if (alignment) {
temp = (alignment > PAGE_SIZE) ? PAGE_MASK : alignment - 1;
} else {
temp = 0;
}
mp->mnt_alignmentmask = (uint32_t)temp;
if (ioqueue_depth > MNT_DEFAULT_IOQUEUE_DEPTH) {
temp = ioqueue_depth;
} else {
temp = MNT_DEFAULT_IOQUEUE_DEPTH;
}
mp->mnt_ioqueue_depth = (uint32_t)temp;
mp->mnt_ioscale = MNT_IOSCALE(mp->mnt_ioqueue_depth);
if (mp->mnt_ioscale > 1) {
printf("ioqueue_depth = %d, ioscale = %d\n", (int)mp->mnt_ioqueue_depth, (int)mp->mnt_ioscale);
}
if (features & DK_FEATURE_FORCE_UNIT_ACCESS) {
mp->mnt_ioflags |= MNT_IOFLAGS_FUA_SUPPORTED;
}
if (VNOP_IOCTL(devvp, DKIOCGETIOMINSATURATIONBYTECOUNT, (caddr_t)&minsaturationbytecount, 0, ctx) == 0) {
mp->mnt_minsaturationbytecount = minsaturationbytecount;
} else {
mp->mnt_minsaturationbytecount = 0;
}
if (VNOP_IOCTL(devvp, DKIOCCORESTORAGE, (caddr_t)&cs_info, 0, ctx) == 0) {
cs_present = TRUE;
}
if (features & DK_FEATURE_UNMAP) {
mp->mnt_ioflags |= MNT_IOFLAGS_UNMAP_SUPPORTED;
if (cs_present == TRUE) {
mp->mnt_ioflags |= MNT_IOFLAGS_CSUNMAP_SUPPORTED;
}
}
if (cs_present == TRUE) {
/*
* for now we'll use the following test as a proxy for
* the underlying drive being FUSION in nature
*/
if ((cs_info.flags & DK_CORESTORAGE_PIN_YOUR_METADATA)) {
mp->mnt_ioflags |= MNT_IOFLAGS_FUSION_DRIVE;
}
} else {
/* Check for APFS Fusion */
dk_apfs_flavour_t flavour;
if ((VNOP_IOCTL(devvp, DKIOCGETAPFSFLAVOUR, (caddr_t)&flavour, 0, ctx) == 0) &&
(flavour == DK_APFS_FUSION)) {
mp->mnt_ioflags |= MNT_IOFLAGS_FUSION_DRIVE;
}
}
if (VNOP_IOCTL(devvp, DKIOCGETLOCATION, (caddr_t)&location, 0, ctx) == 0) {
if (location & DK_LOCATION_EXTERNAL) {
mp->mnt_ioflags |= MNT_IOFLAGS_PERIPHERAL_DRIVE;
mp->mnt_flag |= MNT_REMOVABLE;
}
}
#if CONFIG_IOSCHED
if (iosched_enabled && (features & DK_FEATURE_PRIORITY)) {
mp->mnt_ioflags |= MNT_IOFLAGS_IOSCHED_SUPPORTED;
throttle_info_disable_throttle(mp->mnt_devbsdunit, (mp->mnt_ioflags & MNT_IOFLAGS_FUSION_DRIVE) != 0);
}
#endif /* CONFIG_IOSCHED */
return error;
}
static struct klist fs_klist;
static LCK_GRP_DECLARE(fs_klist_lck_grp, "fs_klist");
static LCK_MTX_DECLARE(fs_klist_lock, &fs_klist_lck_grp);
void
vfs_event_init(void)
{
klist_init(&fs_klist);
}
void
vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data)
{
if (event == VQ_DEAD || event == VQ_NOTRESP) {
struct mount *mp = vfs_getvfs(fsid);
if (mp) {
mount_lock_spin(mp);
if (data) {
mp->mnt_kern_flag &= ~MNT_LNOTRESP; // Now responding
} else {
mp->mnt_kern_flag |= MNT_LNOTRESP; // Not responding
}
mount_unlock(mp);
}
}
lck_mtx_lock(&fs_klist_lock);
KNOTE(&fs_klist, event);
lck_mtx_unlock(&fs_klist_lock);
}
/*
* return the number of mounted filesystems.
*/
static int
sysctl_vfs_getvfscnt(void)
{
return mount_getvfscnt();
}
static int
mount_getvfscnt(void)
{
int ret;
mount_list_lock();
ret = nummounts;
mount_list_unlock();
return ret;
}
static int
mount_fillfsids(fsid_t *fsidlst, int count)
{
struct mount *mp;
int actual = 0;
actual = 0;
mount_list_lock();
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
if (actual < count) {
fsidlst[actual] = mp->mnt_vfsstat.f_fsid;
actual++;
}
}
mount_list_unlock();
return actual;
}
/*
* fill in the array of fsid_t's up to a max of 'count', the actual
* number filled in will be set in '*actual'. If there are more fsid_t's
* than room in fsidlst then ENOMEM will be returned and '*actual' will
* have the actual count.
* having *actual filled out even in the error case is depended upon.
*/
static int
sysctl_vfs_getvfslist(fsid_t *fsidlst, unsigned long count, unsigned long *actual)
{
struct mount *mp;
*actual = 0;
mount_list_lock();
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
(*actual)++;
if (*actual <= count) {
fsidlst[(*actual) - 1] = mp->mnt_vfsstat.f_fsid;
}
}
mount_list_unlock();
return *actual <= count ? 0 : ENOMEM;
}
static int
sysctl_vfs_vfslist(__unused struct sysctl_oid *oidp, __unused void *arg1,
__unused int arg2, struct sysctl_req *req)
{
unsigned long actual;
int error;
size_t space;
fsid_t *fsidlst;
/* This is a readonly node. */
if (req->newptr != USER_ADDR_NULL) {
return EPERM;
}
/* they are querying us so just return the space required. */
if (req->oldptr == USER_ADDR_NULL) {
req->oldidx = sysctl_vfs_getvfscnt() * sizeof(fsid_t);
return 0;
}
again:
/*
* Retrieve an accurate count of the amount of space required to copy
* out all the fsids in the system.
*/
space = req->oldlen;
req->oldlen = sysctl_vfs_getvfscnt() * sizeof(fsid_t);
/* they didn't give us enough space. */
if (space < req->oldlen) {
return ENOMEM;
}
fsidlst = kalloc_data(req->oldlen, Z_WAITOK | Z_ZERO);
if (fsidlst == NULL) {
return ENOMEM;
}
error = sysctl_vfs_getvfslist(fsidlst, req->oldlen / sizeof(fsid_t),
&actual);
/*
* If we get back ENOMEM, then another mount has been added while we
* slept in malloc above. If this is the case then try again.
*/
if (error == ENOMEM) {
kfree_data(fsidlst, req->oldlen);
req->oldlen = space;
goto again;
}
if (error == 0) {
error = SYSCTL_OUT(req, fsidlst, actual * sizeof(fsid_t));
}
kfree_data(fsidlst, req->oldlen);
return error;
}
/*
* Do a sysctl by fsid.
*/
static int
sysctl_vfs_ctlbyfsid(__unused struct sysctl_oid *oidp, void *arg1, int arg2,
struct sysctl_req *req)
{
union union_vfsidctl vc;
struct mount *mp = NULL;
struct vfsstatfs *sp;
int *name, namelen;
int flags = 0;
int error = 0, gotref = 0;
vfs_context_t ctx = vfs_context_current();
proc_t p = req->p; /* XXX req->p != current_proc()? */
boolean_t is_64_bit;
union {
struct statfs64 sfs64;
struct user64_statfs osfs64;
struct user32_statfs osfs32;
} *sfsbuf;
if (req->newptr == USER_ADDR_NULL) {
error = EINVAL;
goto out;
}
name = arg1;
namelen = arg2;
is_64_bit = proc_is64bit(p);
error = SYSCTL_IN(req, &vc, is_64_bit? sizeof(vc.vc64):sizeof(vc.vc32));
if (error) {
goto out;
}
if (vc.vc32.vc_vers != VFS_CTL_VERS1) { /* works for 32 and 64 */
error = EINVAL;
goto out;
}
mp = mount_list_lookupby_fsid(&vc.vc32.vc_fsid, 0, 1); /* works for 32 and 64 */
if (mp == NULL) {
error = ENOENT;
goto out;
}
gotref = 1;
/* reset so that the fs specific code can fetch it. */
req->newidx = 0;
/*
* Note if this is a VFS_CTL then we pass the actual sysctl req
* in for "oldp" so that the lower layer can DTRT and use the
* SYSCTL_IN/OUT routines.
*/
if (mp->mnt_op->vfs_sysctl != NULL) {
if (is_64_bit) {
if (vfs_64bitready(mp)) {
error = mp->mnt_op->vfs_sysctl(name, namelen,
CAST_USER_ADDR_T(req),
NULL, USER_ADDR_NULL, 0,
ctx);
} else {
error = ENOTSUP;
}
} else {
error = mp->mnt_op->vfs_sysctl(name, namelen,
CAST_USER_ADDR_T(req),
NULL, USER_ADDR_NULL, 0,
ctx);
}
if (error != ENOTSUP) {
goto out;
}
}
switch (name[0]) {
case VFS_CTL_UMOUNT:
#if CONFIG_MACF
error = mac_mount_check_umount(ctx, mp);
if (error != 0) {
goto out;
}
#endif
req->newidx = 0;
if (is_64_bit) {
req->newptr = vc.vc64.vc_ptr;
req->newlen = (size_t)vc.vc64.vc_len;
} else {
req->newptr = CAST_USER_ADDR_T(vc.vc32.vc_ptr);
req->newlen = vc.vc32.vc_len;
}
error = SYSCTL_IN(req, &flags, sizeof(flags));
if (error) {
break;
}
mount_ref(mp, 0);
mount_iterdrop(mp);
gotref = 0;
/* safedounmount consumes a ref */
error = safedounmount(mp, flags, ctx);
break;
case VFS_CTL_OSTATFS:
case VFS_CTL_STATFS64:
#if CONFIG_MACF
error = mac_mount_check_stat(ctx, mp);
if (error != 0) {
break;
}
#endif
req->newidx = 0;
if (is_64_bit) {
req->newptr = vc.vc64.vc_ptr;
req->newlen = (size_t)vc.vc64.vc_len;
} else {
req->newptr = CAST_USER_ADDR_T(vc.vc32.vc_ptr);
req->newlen = vc.vc32.vc_len;
}
error = SYSCTL_IN(req, &flags, sizeof(flags));
if (error) {
break;
}
sp = &mp->mnt_vfsstat;
if (((flags & MNT_NOWAIT) == 0 || (flags & (MNT_WAIT | MNT_DWAIT))) &&
(error = vfs_update_vfsstat(mp, ctx, VFS_USER_EVENT))) {
goto out;
}
sfsbuf = kalloc_type(typeof(*sfsbuf), Z_WAITOK);
if (name[0] == VFS_CTL_STATFS64) {
struct statfs64 *sfs = &sfsbuf->sfs64;
vfs_get_statfs64(mp, sfs);
error = SYSCTL_OUT(req, sfs, sizeof(*sfs));
} else if (is_64_bit) {
struct user64_statfs *sfs = &sfsbuf->osfs64;
bzero(sfs, sizeof(*sfs));
sfs->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
sfs->f_type = (short)mp->mnt_vtable->vfc_typenum;
sfs->f_bsize = (user64_long_t)sp->f_bsize;
sfs->f_iosize = (user64_long_t)sp->f_iosize;
sfs->f_blocks = (user64_long_t)sp->f_blocks;
sfs->f_bfree = (user64_long_t)sp->f_bfree;
sfs->f_bavail = (user64_long_t)sp->f_bavail;
sfs->f_files = (user64_long_t)sp->f_files;
sfs->f_ffree = (user64_long_t)sp->f_ffree;
sfs->f_fsid = sp->f_fsid;
sfs->f_owner = sp->f_owner;
vfs_getfstypename(mp, sfs->f_fstypename, MFSNAMELEN);
strlcpy(sfs->f_mntonname, sp->f_mntonname, MNAMELEN);
strlcpy(sfs->f_mntfromname, sp->f_mntfromname, MNAMELEN);
error = SYSCTL_OUT(req, sfs, sizeof(*sfs));
} else {
struct user32_statfs *sfs = &sfsbuf->osfs32;
long temp;
bzero(sfs, sizeof(*sfs));
sfs->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
sfs->f_type = (short)mp->mnt_vtable->vfc_typenum;
/*
* It's possible for there to be more than 2^^31 blocks in the filesystem, so we
* have to fudge the numbers here in that case. We inflate the blocksize in order
* to reflect the filesystem size as best we can.
*/
if (sp->f_blocks > INT_MAX) {
int shift;
/*
* Work out how far we have to shift the block count down to make it fit.
* Note that it's possible to have to shift so far that the resulting
* blocksize would be unreportably large. At that point, we will clip
* any values that don't fit.
*
* For safety's sake, we also ensure that f_iosize is never reported as
* being smaller than f_bsize.
*/
for (shift = 0; shift < 32; shift++) {
if ((sp->f_blocks >> shift) <= INT_MAX) {
break;
}
if ((((long long)sp->f_bsize) << (shift + 1)) > INT_MAX) {
break;
}
}
#define __SHIFT_OR_CLIP(x, s) ((((x) >> (s)) > INT_MAX) ? INT_MAX : ((x) >> (s)))
sfs->f_blocks = (user32_long_t)__SHIFT_OR_CLIP(sp->f_blocks, shift);
sfs->f_bfree = (user32_long_t)__SHIFT_OR_CLIP(sp->f_bfree, shift);
sfs->f_bavail = (user32_long_t)__SHIFT_OR_CLIP(sp->f_bavail, shift);
#undef __SHIFT_OR_CLIP
sfs->f_bsize = (user32_long_t)(sp->f_bsize << shift);
temp = lmax(sp->f_iosize, sp->f_bsize);
if (temp > INT32_MAX) {
error = EINVAL;
kfree_type(typeof(*sfsbuf), sfsbuf);
goto out;
}
sfs->f_iosize = (user32_long_t)temp;
} else {
sfs->f_bsize = (user32_long_t)sp->f_bsize;
sfs->f_iosize = (user32_long_t)sp->f_iosize;
sfs->f_blocks = (user32_long_t)sp->f_blocks;
sfs->f_bfree = (user32_long_t)sp->f_bfree;
sfs->f_bavail = (user32_long_t)sp->f_bavail;
}
sfs->f_files = (user32_long_t)sp->f_files;
sfs->f_ffree = (user32_long_t)sp->f_ffree;
sfs->f_fsid = sp->f_fsid;
sfs->f_owner = sp->f_owner;
vfs_getfstypename(mp, sfs->f_fstypename, MFSNAMELEN);
strlcpy(sfs->f_mntonname, sp->f_mntonname, MNAMELEN);
strlcpy(sfs->f_mntfromname, sp->f_mntfromname, MNAMELEN);
error = SYSCTL_OUT(req, sfs, sizeof(*sfs));
}
kfree_type(typeof(*sfsbuf), sfsbuf);
break;
default:
error = ENOTSUP;
goto out;
}
out:
if (gotref != 0) {
mount_iterdrop(mp);
}
return error;
}
static int filt_fsattach(struct knote *kn, struct kevent_qos_s *kev);
static void filt_fsdetach(struct knote *kn);
static int filt_fsevent(struct knote *kn, long hint);
static int filt_fstouch(struct knote *kn, struct kevent_qos_s *kev);
static int filt_fsprocess(struct knote *kn, struct kevent_qos_s *kev);
SECURITY_READ_ONLY_EARLY(struct filterops) fs_filtops = {
.f_attach = filt_fsattach,
.f_detach = filt_fsdetach,
.f_event = filt_fsevent,
.f_touch = filt_fstouch,
.f_process = filt_fsprocess,
};
static int
filt_fsattach(struct knote *kn, __unused struct kevent_qos_s *kev)
{
kn->kn_flags |= EV_CLEAR; /* automatic */
kn->kn_sdata = 0; /* incoming data is ignored */
lck_mtx_lock(&fs_klist_lock);
KNOTE_ATTACH(&fs_klist, kn);
lck_mtx_unlock(&fs_klist_lock);
/*
* filter only sees future events,
* so it can't be fired already.
*/
return 0;
}
static void
filt_fsdetach(struct knote *kn)
{
lck_mtx_lock(&fs_klist_lock);
KNOTE_DETACH(&fs_klist, kn);
lck_mtx_unlock(&fs_klist_lock);
}
static int
filt_fsevent(struct knote *kn, long hint)
{
/*
* Backwards compatibility:
* Other filters would do nothing if kn->kn_sfflags == 0
*/
if ((kn->kn_sfflags == 0) || (kn->kn_sfflags & hint)) {
kn->kn_fflags |= hint;
}
return kn->kn_fflags != 0;
}
static int
filt_fstouch(struct knote *kn, struct kevent_qos_s *kev)
{
int res;
lck_mtx_lock(&fs_klist_lock);
kn->kn_sfflags = kev->fflags;
/*
* the above filter function sets bits even if nobody is looking for them.
* Just preserve those bits even in the new mask is more selective
* than before.
*
* For compatibility with previous implementations, we leave kn_fflags
* as they were before.
*/
//if (kn->kn_sfflags)
// kn->kn_fflags &= kn->kn_sfflags;
res = (kn->kn_fflags != 0);
lck_mtx_unlock(&fs_klist_lock);
return res;
}
static int
filt_fsprocess(struct knote *kn, struct kevent_qos_s *kev)
{
int res = 0;
lck_mtx_lock(&fs_klist_lock);
if (kn->kn_fflags) {
knote_fill_kevent(kn, kev, 0);
res = 1;
}
lck_mtx_unlock(&fs_klist_lock);
return res;
}
static int
sysctl_vfs_noremotehang(__unused struct sysctl_oid *oidp,
__unused void *arg1, __unused int arg2, struct sysctl_req *req)
{
int out, error;
pid_t pid;
proc_t p;
/* We need a pid. */
if (req->newptr == USER_ADDR_NULL) {
return EINVAL;
}
error = SYSCTL_IN(req, &pid, sizeof(pid));
if (error) {
return error;
}
p = proc_find(pid < 0 ? -pid : pid);
if (p == NULL) {
return ESRCH;
}
/*
* Fetching the value is ok, but we only fetch if the old
* pointer is given.
*/
if (req->oldptr != USER_ADDR_NULL) {
out = !((p->p_flag & P_NOREMOTEHANG) == 0);
proc_rele(p);
error = SYSCTL_OUT(req, &out, sizeof(out));
return error;
}
/* cansignal offers us enough security. */
if (p != req->p && proc_suser(req->p) != 0) {
proc_rele(p);
return EPERM;
}
if (pid < 0) {
OSBitAndAtomic(~((uint32_t)P_NOREMOTEHANG), &p->p_flag);
} else {
OSBitOrAtomic(P_NOREMOTEHANG, &p->p_flag);
}
proc_rele(p);
return 0;
}
static int
sysctl_vfs_generic_conf SYSCTL_HANDLER_ARGS
{
int *name, namelen;
struct vfstable *vfsp;
struct vfsconf vfsc = {};
(void)oidp;
name = arg1;
namelen = arg2;
if (namelen < 1) {
return EISDIR;
} else if (namelen > 1) {
return ENOTDIR;
}
mount_list_lock();
for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
if (vfsp->vfc_typenum == name[0]) {
break;
}
}
if (vfsp == NULL) {
mount_list_unlock();
return ENOTSUP;
}
vfsc.vfc_reserved1 = 0;
bcopy(vfsp->vfc_name, vfsc.vfc_name, sizeof(vfsc.vfc_name));
vfsc.vfc_typenum = vfsp->vfc_typenum;
vfsc.vfc_refcount = vfsp->vfc_refcount;
vfsc.vfc_flags = vfsp->vfc_flags;
vfsc.vfc_reserved2 = 0;
vfsc.vfc_reserved3 = 0;
mount_list_unlock();
return SYSCTL_OUT(req, &vfsc, sizeof(struct vfsconf));
}
/* the vfs.generic. branch. */
SYSCTL_EXTENSIBLE_NODE(_vfs, VFS_GENERIC, generic,
CTLFLAG_RW | CTLFLAG_LOCKED, NULL, "vfs generic hinge");
/* retreive a list of mounted filesystem fsid_t */
SYSCTL_PROC(_vfs_generic, OID_AUTO, vfsidlist,
CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
NULL, 0, sysctl_vfs_vfslist, "S,fsid", "List of mounted filesystem ids");
/* perform operations on filesystem via fsid_t */
SYSCTL_NODE(_vfs_generic, OID_AUTO, ctlbyfsid, CTLFLAG_RW | CTLFLAG_LOCKED,
sysctl_vfs_ctlbyfsid, "ctlbyfsid");
SYSCTL_PROC(_vfs_generic, OID_AUTO, noremotehang, CTLFLAG_RW | CTLFLAG_ANYBODY,
NULL, 0, sysctl_vfs_noremotehang, "I", "noremotehang");
SYSCTL_INT(_vfs_generic, VFS_MAXTYPENUM, maxtypenum,
CTLFLAG_RD | CTLFLAG_KERN | CTLFLAG_LOCKED,
&maxvfstypenum, 0, "");
SYSCTL_INT(_vfs_generic, OID_AUTO, sync_timeout, CTLFLAG_RW | CTLFLAG_LOCKED, &sync_timeout_seconds, 0, "");
SYSCTL_NODE(_vfs_generic, VFS_CONF, conf,
CTLFLAG_RD | CTLFLAG_LOCKED,
sysctl_vfs_generic_conf, "");
#if DEVELOPMENT || DEBUG
SYSCTL_INT(_vfs_generic, OID_AUTO, print_busy_vnodes,
CTLTYPE_INT | CTLFLAG_RW,
&print_busy_vnodes, 0,
"VFS log busy vnodes blocking unmount");
#endif
/* Indicate that the root file system unmounted cleanly */
static int vfs_root_unmounted_cleanly = 0;
SYSCTL_INT(_vfs_generic, OID_AUTO, root_unmounted_cleanly, CTLFLAG_RD, &vfs_root_unmounted_cleanly, 0, "Root filesystem was unmounted cleanly");
void
vfs_set_root_unmounted_cleanly(void)
{
vfs_root_unmounted_cleanly = 1;
}
/*
* Print vnode state.
*/
void
vn_print_state(struct vnode *vp, const char *fmt, ...)
{
va_list ap;
char perm_str[] = "(VM_KERNEL_ADDRPERM pointer)";
char fs_name[MFSNAMELEN];
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
printf("vp 0x%0llx %s: ", (uint64_t)VM_KERNEL_ADDRPERM(vp), perm_str);
printf("tag %d, type %d\n", vp->v_tag, vp->v_type);
/* Counts .. */
printf(" iocount %d, usecount %d, kusecount %d references %d\n",
vp->v_iocount, vp->v_usecount, vp->v_kusecount, vp->v_references);
printf(" writecount %d, numoutput %d\n", vp->v_writecount,
vp->v_numoutput);
/* Flags */
printf(" flag 0x%x, lflag 0x%x, listflag 0x%x\n", vp->v_flag,
vp->v_lflag, vp->v_listflag);
if (vp->v_mount == NULL || vp->v_mount == dead_mountp) {
strlcpy(fs_name, "deadfs", MFSNAMELEN);
} else {
vfs_name(vp->v_mount, fs_name);
}
printf(" v_data 0x%0llx %s\n",
(vp->v_data ? (uint64_t)VM_KERNEL_ADDRPERM(vp->v_data) : 0),
perm_str);
printf(" v_mount 0x%0llx %s vfs_name %s\n",
(vp->v_mount ? (uint64_t)VM_KERNEL_ADDRPERM(vp->v_mount) : 0),
perm_str, fs_name);
}
long num_reusedvnodes = 0;
static vnode_t
process_vp(vnode_t vp, int want_vp, bool can_defer, int *deferred)
{
unsigned int vpid;
*deferred = 0;
vpid = vp->v_id;
vnode_list_remove_locked(vp);
vnode_hold(vp);
vnode_list_unlock();
vnode_lock_spin(vp);
/*
* We could wait for the vnode_lock after removing the vp from the freelist
* and the vid is bumped only at the very end of reclaim. So it is possible
* that we are looking at a vnode that is being terminated. If so skip it.
*/
if ((vpid != vp->v_id) || (vp->v_usecount != 0) || (vp->v_iocount != 0) ||
VONLIST(vp) || (vp->v_lflag & VL_TERMINATE)) {
/*
* we lost the race between dropping the list lock
* and picking up the vnode_lock... someone else
* used this vnode and it is now in a new state
*/
vnode_drop_and_unlock(vp);
return NULLVP;
}
if ((vp->v_lflag & (VL_NEEDINACTIVE | VL_MARKTERM)) == VL_NEEDINACTIVE) {
/*
* we did a vnode_rele_ext that asked for
* us not to reenter the filesystem during
* the release even though VL_NEEDINACTIVE was
* set... we'll do it here by doing a
* vnode_get/vnode_put
*
* pick up an iocount so that we can call
* vnode_put and drive the VNOP_INACTIVE...
* vnode_put will either leave us off
* the freelist if a new ref comes in,
* or put us back on the end of the freelist
* or recycle us if we were marked for termination...
* so we'll just go grab a new candidate
*/
vp->v_iocount++;
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_put_locked(vp);
vnode_drop_and_unlock(vp);
return NULLVP;
}
/*
* Checks for anyone racing us for recycle
*/
if (vp->v_type != VBAD) {
if ((want_vp || can_defer) && (vnode_on_reliable_media(vp) == FALSE || (vp->v_flag & VISDIRTY))) {
vnode_async_list_add(vp);
vnode_drop_and_unlock(vp);
*deferred = 1;
return NULLVP;
}
if (vp->v_lflag & VL_DEAD) {
panic("new_vnode(%p): the vnode is VL_DEAD but not VBAD", vp);
}
vnode_lock_convert(vp);
(void)vnode_reclaim_internal(vp, 1, want_vp, 0);
if (want_vp) {
if ((VONLIST(vp))) {
panic("new_vnode(%p): vp on list", vp);
}
if (vp->v_usecount || vp->v_iocount || vp->v_kusecount ||
(vp->v_lflag & (VNAMED_UBC | VNAMED_MOUNT | VNAMED_FSHASH))) {
panic("new_vnode(%p): free vnode still referenced", vp);
}
if ((vp->v_mntvnodes.tqe_prev != 0) && (vp->v_mntvnodes.tqe_next != 0)) {
panic("new_vnode(%p): vnode seems to be on mount list", vp);
}
if (!LIST_EMPTY(&vp->v_nclinks) || !TAILQ_EMPTY(&vp->v_ncchildren)) {
panic("new_vnode(%p): vnode still hooked into the name cache", vp);
}
} else {
vnode_drop_and_unlock(vp);
vp = NULLVP;
}
}
return vp;
}
__attribute__((noreturn))
static void
async_work_continue(void)
{
struct async_work_lst *q;
int deferred;
vnode_t vp;
q = &vnode_async_work_list;
for (;;) {
vnode_list_lock();
if (TAILQ_EMPTY(q)) {
assert_wait(q, (THREAD_UNINT));
vnode_list_unlock();
thread_block((thread_continue_t)async_work_continue);
continue;
}
async_work_handled++;
vp = TAILQ_FIRST(q);
vp = process_vp(vp, 0, false, &deferred);
if (vp != NULLVP) {
panic("found VBAD vp (%p) on async queue", vp);
}
}
}
#if CONFIG_JETSAM
bool do_async_jetsam = false;
#endif
__attribute__((noreturn))
static void
vn_laundry_continue(void)
{
struct freelst *free_q;
struct ragelst *rage_q;
vnode_t vp;
int deferred;
bool rage_q_empty;
bool free_q_empty;
free_q = &vnode_free_list;
rage_q = &vnode_rage_list;
for (;;) {
vnode_list_lock();
#if CONFIG_JETSAM
if (do_async_jetsam) {
do_async_jetsam = false;
if (deadvnodes <= deadvnodes_low) {
vnode_list_unlock();
log(LOG_EMERG, "Initiating vnode jetsam : %d desired, %ld numvnodes, "
"%ld free, %ld dead, %ld async, %d rage\n",
desiredvnodes, numvnodes, freevnodes, deadvnodes, async_work_vnodes, ragevnodes);
memorystatus_kill_on_vnode_limit();
continue;
}
}
#endif
if (!TAILQ_EMPTY(&vnode_async_work_list)) {
vp = TAILQ_FIRST(&vnode_async_work_list);
async_work_handled++;
vp = process_vp(vp, 0, false, &deferred);
if (vp != NULLVP) {
panic("found VBAD vp (%p) on async queue", vp);
}
continue;
}
free_q_empty = TAILQ_EMPTY(free_q);
rage_q_empty = TAILQ_EMPTY(rage_q);
if (!rage_q_empty && !free_q_empty) {
struct timeval current_tv;
microuptime(&current_tv);
if (ragevnodes < rage_limit &&
((current_tv.tv_sec - rage_tv.tv_sec) < RAGE_TIME_LIMIT)) {
rage_q_empty = true;
}
}
if (numvnodes < numvnodes_min || (rage_q_empty && free_q_empty) ||
(reusablevnodes <= reusablevnodes_max && deadvnodes >= deadvnodes_high)) {
assert_wait(free_q, (THREAD_UNINT));
vnode_list_unlock();
thread_block((thread_continue_t)vn_laundry_continue);
continue;
}
if (!rage_q_empty) {
vp = TAILQ_FIRST(rage_q);
} else {
vp = TAILQ_FIRST(free_q);
}
vp = process_vp(vp, 0, false, &deferred);
if (vp != NULLVP) {
/* If process_vp returns a vnode, it is locked and has a holdcount */
vnode_drop_and_unlock(vp);
vp = NULLVP;
}
}
}
static inline void
wakeup_laundry_thread()
{
if (deadvnodes_noreuse || (numvnodes >= numvnodes_min && deadvnodes < deadvnodes_low &&
(reusablevnodes > reusablevnodes_max || numvnodes >= desiredvnodes))) {
wakeup(&vnode_free_list);
}
}
/*
* This must be called under vnode_list_lock() to prevent race when accessing
* various vnode stats.
*/
static void
send_freeable_vnodes_telemetry(void)
{
bool send_event = false;
/*
* Log an event when the 'numvnodes' is above the freeable vnodes threshold
* or when it falls back within the threshold.
* When the 'numvnodes' is above the threshold, log an event when it has
* been incrementally growing by 25%.
*/
if ((numvnodes > desiredvnodes) && (freevnodes + deadvnodes) == 0) {
long last_numvnodes = freeable_vnodes_telemetry.numvnodes;
if (numvnodes > (last_numvnodes + ((last_numvnodes * 25) / 100)) ||
numvnodes >= numvnodes_max) {
send_event = true;
}
freeablevnodes_threshold_crossed = true;
} else if (freeablevnodes_threshold_crossed &&
(freevnodes + deadvnodes) > busyvnodes) {
freeablevnodes_threshold_crossed = false;
send_event = true;
}
if (__improbable(send_event)) {
ca_event_t event = CA_EVENT_ALLOCATE_FLAGS(freeable_vnodes, Z_NOWAIT);
if (event) {
/*
* Update the stats except the 'numvnodes_max' and 'desiredvnodes'
* as they are immutable after init.
*/
freeable_vnodes_telemetry.numvnodes_min = numvnodes_min;
freeable_vnodes_telemetry.numvnodes = numvnodes;
freeable_vnodes_telemetry.freevnodes = freevnodes;
freeable_vnodes_telemetry.deadvnodes = deadvnodes;
freeable_vnodes_telemetry.freeablevnodes = freeablevnodes;
freeable_vnodes_telemetry.busyvnodes = busyvnodes;
freeable_vnodes_telemetry.threshold_crossed =
freeablevnodes_threshold_crossed;
memcpy(event->data, &freeable_vnodes_telemetry,
sizeof(CA_EVENT_TYPE(freeable_vnodes)));
if (!freeablevnodes_threshold_crossed) {
freeable_vnodes_telemetry.numvnodes = 0;
}
CA_EVENT_SEND(event);
}
}
}
static int
new_vnode(vnode_t *vpp, bool can_free)
{
long force_alloc_min;
vnode_t vp;
#if CONFIG_JETSAM
uint32_t retries = 0, max_retries = 2; /* retry incase of tablefull */
#else
uint32_t retries = 0, max_retries = 100; /* retry incase of tablefull */
#endif
int force_alloc = 0, walk_count = 0;
boolean_t need_reliable_vp = FALSE;
int deferred;
struct timeval initial_tv;
struct timeval current_tv;
proc_t curproc = current_proc();
bool force_alloc_freeable = false;
if (vn_dealloc_level == DEALLOC_VNODE_NONE) {
can_free = false;
}
initial_tv.tv_sec = 0;
retry:
vp = NULLVP;
vnode_list_lock();
newvnode++;
if (need_reliable_vp == TRUE) {
async_work_timed_out++;
}
/*
* The vnode list lock was dropped after force_alloc_freeable was set,
* reevaluate.
*/
force_alloc_min = MAX(desiredvnodes, numvnodes_min);
if (force_alloc_freeable &&
(numvnodes < force_alloc_min || numvnodes >= numvnodes_max)) {
force_alloc_freeable = false;
}
#if CONFIG_JETSAM
if ((numvnodes_max > desiredvnodes) && numvnodes > (numvnodes_max - 100)
#if (DEVELOPMENT || DEBUG)
&& !bootarg_no_vnode_jetsam
#endif
) {
do_async_jetsam = true;
wakeup(&vnode_free_list);
}
#endif /* CONFIG_JETSAM */
if (((numvnodes - deadvnodes + deadvnodes_noreuse) < desiredvnodes) ||
force_alloc || force_alloc_freeable) {
struct timespec ts;
uint32_t vflag = 0;
/*
* Can always reuse a dead one except if it is in the process of
* being freed or the FS cannot handle freeable vnodes.
*/
if (!TAILQ_EMPTY(&vnode_dead_list)) {
/* Select an appropriate deadvnode */
if (numvnodes <= numvnodes_min || !can_free) {
/* all vnodes upto numvnodes_min are not freeable */
vp = TAILQ_FIRST(&vnode_dead_list);
if (numvnodes > numvnodes_min &&
(vp->v_flag & VCANDEALLOC)) {
/*
* Freeable vnodes are added to the
* back of the queue, so if the first
* from the front is freeable, then
* there are none on the dead list.
*/
vp = NULLVP;
}
} else {
/*
* Filesystems which opt in to freeable vnodes
* can get either one.
*/
TAILQ_FOREACH_REVERSE(vp, &vnode_dead_list,
deadlst, v_freelist) {
if (!(vp->v_listflag & VLIST_NO_REUSE)) {
break;
}
}
}
if (vp) {
force_alloc_freeable = false;
goto steal_this_vp;
}
}
/*
* no dead vnodes available... if we're under
* the limit, we'll create a new vnode
*/
numvnodes++;
if (force_alloc) {
numvnodes_min++;
} else if (can_free && (numvnodes > numvnodes_min)) {
allocedvnodes++;
freeablevnodes++;
vflag = VCANDEALLOC;
send_freeable_vnodes_telemetry();
}
vnode_list_unlock();
if (nc_smr_enabled) {
vp = zalloc_smr(vnode_zone, Z_WAITOK_ZERO_NOFAIL);
} else {
vp = zalloc_flags(vnode_zone, Z_WAITOK_ZERO_NOFAIL);
}
VLISTNONE(vp); /* avoid double queue removal */
lck_mtx_init(&vp->v_lock, &vnode_lck_grp, &vnode_lck_attr);
TAILQ_INIT(&vp->v_ncchildren);
klist_init(&vp->v_knotes);
nanouptime(&ts);
vp->v_id = (uint32_t)ts.tv_nsec;
vp->v_flag = VSTANDARD | vflag;
if (force_alloc_freeable) {
/* This vnode should be recycled and freed immediately */
vp->v_lflag = VL_MARKTERM;
vp->v_listflag = VLIST_NO_REUSE;
}
if (vflag & VCANDEALLOC) {
os_atomic_inc(&busyvnodes, relaxed);
}
#if CONFIG_MACF
if (mac_vnode_label_init_needed(vp)) {
mac_vnode_label_init(vp);
}
#endif /* MAC */
#if CONFIG_IOCOUNT_TRACE
if (__improbable(bootarg_vnode_iocount_trace)) {
vp->v_iocount_trace = (vnode_iocount_trace_t)zalloc_permanent(
IOCOUNT_TRACE_MAX_TYPES * sizeof(struct vnode_iocount_trace),
ZALIGN(struct vnode_iocount_trace));
}
#endif /* CONFIG_IOCOUNT_TRACE */
#if CONFIG_FILE_LEASES
LIST_INIT(&vp->v_leases);
#endif
vp->v_iocount = 1;
goto done;
}
microuptime(&current_tv);
#define MAX_WALK_COUNT 1000
if (!TAILQ_EMPTY(&vnode_rage_list) &&
(ragevnodes >= rage_limit ||
(current_tv.tv_sec - rage_tv.tv_sec) >= RAGE_TIME_LIMIT)) {
TAILQ_FOREACH(vp, &vnode_rage_list, v_freelist) {
if (!(vp->v_listflag & VLIST_RAGE)) {
panic("new_vnode: vp (%p) on RAGE list not marked VLIST_RAGE", vp);
}
// if we're a dependency-capable process, skip vnodes that can
// cause recycling deadlocks. (i.e. this process is diskimages
// helper and the vnode is in a disk image). Querying the
// mnt_kern_flag for the mount's virtual device status
// is safer than checking the mnt_dependent_process, which
// may not be updated if there are multiple devnode layers
// in between the disk image and the final consumer.
if (((curproc->p_flag & P_DEPENDENCY_CAPABLE) == 0 || vp->v_mount == NULL ||
(vp->v_mount->mnt_kern_flag & MNTK_VIRTUALDEV) == 0) &&
!(vp->v_listflag & VLIST_NO_REUSE) &&
(can_free || !(vp->v_flag & VCANDEALLOC))) {
/*
* if need_reliable_vp == TRUE, then we've already sent one or more
* non-reliable vnodes to the async thread for processing and timed
* out waiting for a dead vnode to show up. Use the MAX_WALK_COUNT
* mechanism to first scan for a reliable vnode before forcing
* a new vnode to be created
*/
if (need_reliable_vp == FALSE || vnode_on_reliable_media(vp) == TRUE) {
break;
}
}
// don't iterate more than MAX_WALK_COUNT vnodes to
// avoid keeping the vnode list lock held for too long.
if (walk_count++ > MAX_WALK_COUNT) {
vp = NULL;
break;
}
}
}
if (vp == NULL && !TAILQ_EMPTY(&vnode_free_list)) {
/*
* Pick the first vp for possible reuse
*/
walk_count = 0;
TAILQ_FOREACH(vp, &vnode_free_list, v_freelist) {
// if we're a dependency-capable process, skip vnodes that can
// cause recycling deadlocks. (i.e. this process is diskimages
// helper and the vnode is in a disk image). Querying the
// mnt_kern_flag for the mount's virtual device status
// is safer than checking the mnt_dependent_process, which
// may not be updated if there are multiple devnode layers
// in between the disk image and the final consumer.
if (((curproc->p_flag & P_DEPENDENCY_CAPABLE) == 0 || vp->v_mount == NULL ||
(vp->v_mount->mnt_kern_flag & MNTK_VIRTUALDEV) == 0) &&
!(vp->v_listflag & VLIST_NO_REUSE) &&
(can_free || !(vp->v_flag & VCANDEALLOC))) {
/*
* if need_reliable_vp == TRUE, then we've already sent one or more
* non-reliable vnodes to the async thread for processing and timed
* out waiting for a dead vnode to show up. Use the MAX_WALK_COUNT
* mechanism to first scan for a reliable vnode before forcing
* a new vnode to be created
*/
if (need_reliable_vp == FALSE || vnode_on_reliable_media(vp) == TRUE) {
break;
}
}
// don't iterate more than MAX_WALK_COUNT vnodes to
// avoid keeping the vnode list lock held for too long.
if (walk_count++ > MAX_WALK_COUNT) {
vp = NULL;
break;
}
}
}
//
// if we don't have a vnode and the walk_count is >= MAX_WALK_COUNT
// then we're trying to create a vnode on behalf of a
// process like diskimages-helper that has file systems
// mounted on top of itself (and thus we can't reclaim
// vnodes in the file systems on top of us). if we can't
// find a vnode to reclaim then we'll just have to force
// the allocation.
//
if (vp == NULL && walk_count >= MAX_WALK_COUNT) {
force_alloc = 1;
vnode_list_unlock();
goto retry;
}
if (vp == NULL) {
if (can_free && (vn_dealloc_level > DEALLOC_VNODE_NONE) &&
(numvnodes >= force_alloc_min) && (numvnodes < numvnodes_max)) {
force_alloc_freeable = true;
vnode_list_unlock();
goto retry;
}
vnode_list_unlock();
/*
* we've reached the system imposed maximum number of vnodes
* but there isn't a single one available
* wait a bit and then retry... if we can't get a vnode
* after our target number of retries, than log a complaint
*/
if (++retries <= max_retries) {
delay_for_interval(1, 1000 * 1000);
goto retry;
}
tablefull("vnode");
log(LOG_EMERG, "%d desired, %ld numvnodes, "
"%ld free, %ld dead, %ld async, %d rage\n",
desiredvnodes, numvnodes, freevnodes, deadvnodes, async_work_vnodes, ragevnodes);
#if CONFIG_JETSAM
/*
* Running out of vnodes tends to make a system unusable. Start killing
* processes that jetsam knows are killable.
*/
if (memorystatus_kill_on_vnode_limit() == FALSE
#if DEVELOPMENT || DEBUG
|| bootarg_no_vnode_jetsam
#endif
) {
/*
* If jetsam can't find any more processes to kill and there
* still aren't any free vnodes, panic. Hopefully we'll get a
* panic log to tell us why we ran out.
*/
panic("vnode table is full");
}
/*
* Now that we've killed someone, wait a bit and continue looking
*/
delay_for_interval(3, 1000 * 1000);
retries = 0;
goto retry;
#endif
*vpp = NULL;
return ENFILE;
}
newvnode_nodead++;
steal_this_vp:
if ((vp = process_vp(vp, 1, true, &deferred)) == NULLVP) {
if (deferred) {
int elapsed_msecs;
struct timeval elapsed_tv;
if (initial_tv.tv_sec == 0) {
microuptime(&initial_tv);
}
vnode_list_lock();
dead_vnode_waited++;
dead_vnode_wanted++;
/*
* note that we're only going to explicitly wait 10ms
* for a dead vnode to become available, since even if one
* isn't available, a reliable vnode might now be available
* at the head of the VRAGE or free lists... if so, we
* can satisfy the new_vnode request with less latency then waiting
* for the full 100ms duration we're ultimately willing to tolerate
*/
assert_wait_timeout((caddr_t)&dead_vnode_wanted, (THREAD_INTERRUPTIBLE), 10000, NSEC_PER_USEC);
vnode_list_unlock();
thread_block(THREAD_CONTINUE_NULL);
microuptime(&elapsed_tv);
timevalsub(&elapsed_tv, &initial_tv);
elapsed_msecs = (int)(elapsed_tv.tv_sec * 1000 + elapsed_tv.tv_usec / 1000);
if (elapsed_msecs >= 100) {
/*
* we've waited long enough... 100ms is
* somewhat arbitrary for this case, but the
* normal worst case latency used for UI
* interaction is 100ms, so I've chosen to
* go with that.
*
* setting need_reliable_vp to TRUE
* forces us to find a reliable vnode
* that we can process synchronously, or
* to create a new one if the scan for
* a reliable one hits the scan limit
*/
need_reliable_vp = TRUE;
}
}
goto retry;
}
OSAddAtomicLong(1, &num_reusedvnodes);
#if CONFIG_MACF
/*
* We should never see VL_LABELWAIT or VL_LABEL here.
* as those operations hold a reference.
*/
assert((vp->v_lflag & VL_LABELWAIT) != VL_LABELWAIT);
assert((vp->v_lflag & VL_LABEL) != VL_LABEL);
if (vp->v_lflag & VL_LABELED || mac_vnode_label(vp) != NULL) {
vnode_lock_convert(vp);
mac_vnode_label_recycle(vp);
} else if (mac_vnode_label_init_needed(vp)) {
vnode_lock_convert(vp);
mac_vnode_label_init(vp);
}
#endif /* MAC */
vp->v_iocount = 1;
vp->v_lflag = 0;
vp->v_writecount = 0;
vp->v_references = 0;
vp->v_iterblkflags = 0;
if (can_free && (vp->v_flag & VCANDEALLOC)) {
vp->v_flag = VSTANDARD | VCANDEALLOC;
} else {
vp->v_flag = VSTANDARD;
}
/* vbad vnodes can point to dead_mountp */
vp->v_mount = NULL;
vp->v_defer_reclaimlist = (vnode_t)0;
/* process_vp returns a locked vnode with a holdcount */
vnode_drop_and_unlock(vp);
done:
*vpp = vp;
return 0;
}
void
vnode_lock(vnode_t vp)
{
lck_mtx_lock(&vp->v_lock);
}
void
vnode_lock_spin(vnode_t vp)
{
lck_mtx_lock_spin(&vp->v_lock);
}
void
vnode_unlock(vnode_t vp)
{
lck_mtx_unlock(&vp->v_lock);
}
void
vnode_hold(vnode_t vp)
{
int32_t old_holdcount = os_atomic_inc_orig(&vp->v_holdcount, relaxed);
if (old_holdcount == INT32_MAX) {
/*
* Because we allow atomic ops on the holdcount it is
* possible that when the vnode is examined, its holdcount
* is different than what will be printed in this
* panic message.
*/
panic("%s: vp %p holdcount overflow from : %d v_tag = %d, v_type = %d, v_flag = %x.",
__FUNCTION__, vp, old_holdcount, vp->v_tag, vp->v_type, vp->v_flag);
}
}
#define VNODE_HOLD_NO_SMR (1<<29) /* Disable vnode_hold_smr */
/*
* To be used when smr is the only protection (cache_lookup and cache_lookup_path)
*/
bool
vnode_hold_smr(vnode_t vp)
{
int32_t holdcount;
/*
* For "high traffic" vnodes like rootvnode, the atomic
* cmpexcg loop below can turn into a infinite loop, no need
* to do it for vnodes that won't be dealloc'ed
*/
if (!(os_atomic_load(&vp->v_flag, relaxed) & VCANDEALLOC)) {
vnode_hold(vp);
return true;
}
for (;;) {
holdcount = os_atomic_load(&vp->v_holdcount, relaxed);
if (holdcount & VNODE_HOLD_NO_SMR) {
return false;
}
if ((os_atomic_cmpxchg(&vp->v_holdcount, holdcount, holdcount + 1, relaxed) != 0)) {
return true;
}
}
}
/*
* free callback from smr enabled zones
*/
static void
vnode_smr_free(void *_vp, __unused size_t _size)
{
vnode_t vp = _vp;
bzero(vp, sizeof(*vp));
}
static vnode_t
vnode_drop_internal(vnode_t vp, bool locked)
{
int32_t old_holdcount = os_atomic_dec_orig(&vp->v_holdcount, relaxed);
if (old_holdcount < 1) {
if (locked) {
vnode_unlock(vp);
}
/*
* Because we allow atomic ops on the holdcount it is possible
* that when the vnode is examined, its holdcount is different
* than what will be printed in this panic message.
*/
panic("%s : vp %p holdcount -ve: %d. v_tag = %d, v_type = %d, v_flag = %x.",
__FUNCTION__, vp, old_holdcount - 1, vp->v_tag, vp->v_type, vp->v_flag);
}
if (vn_dealloc_level == DEALLOC_VNODE_NONE || old_holdcount > 1 ||
!(vp->v_flag & VCANDEALLOC) || !(vp->v_lflag & VL_DEAD)) {
if (locked) {
vnode_unlock(vp);
}
return vp;
}
if (!locked) {
vnode_lock(vp);
}
if ((os_atomic_load(&vp->v_holdcount, relaxed) != 0) || vp->v_iocount ||
vp->v_usecount || !(vp->v_flag & VCANDEALLOC) || !(vp->v_lflag & VL_DEAD)) {
vnode_unlock(vp);
return vp;
}
vnode_list_lock();
/*
* the v_listflag field is protected by the vnode_list_lock
*/
if (VONLIST(vp) && (vp->v_listflag & VLIST_DEAD) &&
(numvnodes > desiredvnodes || (vp->v_listflag & VLIST_NO_REUSE) ||
vn_dealloc_level != DEALLOC_VNODE_ALL || deadvnodes >= deadvnodes_high) &&
(os_atomic_cmpxchg(&vp->v_holdcount, 0, VNODE_HOLD_NO_SMR, relaxed) != 0)) {
VREMDEAD("vnode_list_remove", vp);
numvnodes--;
freeablevnodes--;
deallocedvnodes++;
vp->v_listflag = 0;
send_freeable_vnodes_telemetry();
vnode_list_unlock();
#if CONFIG_MACF
struct label *tmpl = mac_vnode_label(vp);
vp->v_label = NULL;
#endif /* CONFIG_MACF */
vnode_unlock(vp);
#if CONFIG_MACF
if (tmpl) {
mac_vnode_label_free(tmpl);
}
#endif /* CONFIG_MACF */
if (nc_smr_enabled) {
zfree_smr(vnode_zone, vp);
} else {
zfree(vnode_zone, vp);
}
vp = NULLVP;
} else {
vnode_list_unlock();
vnode_unlock(vp);
}
return vp;
}
vnode_t
vnode_drop_and_unlock(vnode_t vp)
{
return vnode_drop_internal(vp, true);
}
vnode_t
vnode_drop(vnode_t vp)
{
return vnode_drop_internal(vp, false);
}
SYSCTL_NODE(_vfs, OID_AUTO, vnstats, CTLFLAG_RD | CTLFLAG_LOCKED, NULL, "vfs vnode stats");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, vn_dealloc_level,
CTLFLAG_RD | CTLFLAG_LOCKED,
&vn_dealloc_level, 0, "");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, desired_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&desiredvnodes, 0, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&numvnodes, "");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, num_vnodes_min,
CTLFLAG_RD | CTLFLAG_LOCKED,
&numvnodes_min, 0, "");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, num_vnodes_max,
CTLFLAG_RD | CTLFLAG_LOCKED,
&numvnodes_max, 0, "");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, num_deallocable_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&freeablevnodes, 0, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_deallocable_busy_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&busyvnodes, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_dead_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&deadvnodes, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_dead_vnodes_to_dealloc,
CTLFLAG_RD | CTLFLAG_LOCKED,
&deadvnodes_noreuse, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_async_work_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&async_work_vnodes, "");
SYSCTL_COMPAT_INT(_vfs_vnstats, OID_AUTO, num_rapid_aging_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&ragevnodes, 0, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_free_vnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&freevnodes, "");
SYSCTL_LONG(_vfs_vnstats, OID_AUTO, num_recycledvnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&num_recycledvnodes, "");
SYSCTL_QUAD(_vfs_vnstats, OID_AUTO, num_allocedvnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&allocedvnodes, "");
SYSCTL_QUAD(_vfs_vnstats, OID_AUTO, num_deallocedvnodes,
CTLFLAG_RD | CTLFLAG_LOCKED,
&deallocedvnodes, "");
SYSCTL_QUAD(_vfs_vnstats, OID_AUTO, num_newvnode_calls,
CTLFLAG_RD | CTLFLAG_LOCKED,
&newvnode, "");
SYSCTL_QUAD(_vfs_vnstats, OID_AUTO, num_newvnode_calls_nodead,
CTLFLAG_RD | CTLFLAG_LOCKED,
&newvnode_nodead, "");
int
vnode_get(struct vnode *vp)
{
int retval;
vnode_lock_spin(vp);
retval = vnode_get_locked(vp);
vnode_unlock(vp);
return retval;
}
int
vnode_get_locked(struct vnode *vp)
{
#if DIAGNOSTIC
lck_mtx_assert(&vp->v_lock, LCK_MTX_ASSERT_OWNED);
#endif
if ((vp->v_iocount == 0) && (vp->v_lflag & (VL_TERMINATE | VL_DEAD))) {
return ENOENT;
}
if (os_add_overflow(vp->v_iocount, 1, &vp->v_iocount)) {
panic("v_iocount overflow");
}
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
return 0;
}
/*
* vnode_getwithvid() cuts in line in front of a vnode drain (that is,
* while the vnode is draining, but at no point after that) to prevent
* deadlocks when getting vnodes from filesystem hashes while holding
* resources that may prevent other iocounts from being released.
*/
int
vnode_getwithvid(vnode_t vp, uint32_t vid)
{
return vget_internal(vp, vid, (VNODE_NODEAD | VNODE_WITHID | VNODE_DRAINO));
}
/*
* vnode_getwithvid_drainok() is like vnode_getwithvid(), but *does* block behind a vnode
* drain; it exists for use in the VFS name cache, where we really do want to block behind
* vnode drain to prevent holding off an unmount.
*/
int
vnode_getwithvid_drainok(vnode_t vp, uint32_t vid)
{
return vget_internal(vp, vid, (VNODE_NODEAD | VNODE_WITHID));
}
int
vnode_getwithref(vnode_t vp)
{
return vget_internal(vp, 0, 0);
}
__private_extern__ int
vnode_getwithref_noblock(vnode_t vp)
{
return vget_internal(vp, 0, VNODE_NOBLOCK);
}
__private_extern__ int
vnode_getalways(vnode_t vp)
{
return vget_internal(vp, 0, VNODE_ALWAYS);
}
__private_extern__ int
vnode_getalways_from_pager(vnode_t vp)
{
return vget_internal(vp, 0, VNODE_ALWAYS | VNODE_PAGER);
}
static inline void
vn_set_dead(vnode_t vp)
{
vp->v_mount = NULL;
vp->v_op = dead_vnodeop_p;
vp->v_tag = VT_NON;
vp->v_data = NULL;
vp->v_type = VBAD;
vp->v_lflag |= VL_DEAD;
}
static int
vnode_put_internal_locked(vnode_t vp, bool from_pager)
{
vfs_context_t ctx = vfs_context_current(); /* hoist outside loop */
#if DIAGNOSTIC
lck_mtx_assert(&vp->v_lock, LCK_MTX_ASSERT_OWNED);
#endif
retry:
if (vp->v_iocount < 1) {
panic("vnode_put(%p): iocount < 1", vp);
}
if ((vp->v_usecount > 0) || (vp->v_iocount > 1)) {
vnode_dropiocount(vp);
return 0;
}
if (((vp->v_lflag & (VL_DEAD | VL_NEEDINACTIVE)) == VL_NEEDINACTIVE)) {
vp->v_lflag &= ~VL_NEEDINACTIVE;
if (UBCINFOEXISTS(vp)) {
ubc_cs_free_and_vnode_unlock(vp);
} else {
vnode_unlock(vp);
}
VNOP_INACTIVE(vp, ctx);
vnode_lock_spin(vp);
/*
* because we had to drop the vnode lock before calling
* VNOP_INACTIVE, the state of this vnode may have changed...
* we may pick up both VL_MARTERM and either
* an iocount or a usecount while in the VNOP_INACTIVE call
* we don't want to call vnode_reclaim_internal on a vnode
* that has active references on it... so loop back around
* and reevaluate the state
*/
goto retry;
}
vp->v_lflag &= ~VL_NEEDINACTIVE;
vnode_lock_convert(vp);
if ((vp->v_lflag & (VL_MARKTERM | VL_TERMINATE | VL_DEAD)) == VL_MARKTERM) {
if (from_pager) {
/*
* We can't initiate reclaim when called from the pager
* because it will deadlock with itself so we hand it
* off to the async cleaner thread.
*/
vnode_async_list_add(vp);
} else {
vnode_reclaim_internal(vp, 1, 1, 0);
}
}
vnode_dropiocount(vp);
vnode_list_add(vp);
return 0;
}
int
vnode_put_locked(vnode_t vp)
{
return vnode_put_internal_locked(vp, false);
}
int
vnode_put(vnode_t vp)
{
int retval;
vnode_lock_spin(vp);
vnode_hold(vp);
retval = vnode_put_internal_locked(vp, false);
vnode_drop_and_unlock(vp);
return retval;
}
int
vnode_put_from_pager(vnode_t vp)
{
int retval;
vnode_lock_spin(vp);
vnode_hold(vp);
/* Cannot initiate reclaim while paging */
retval = vnode_put_internal_locked(vp, true);
vnode_drop_and_unlock(vp);
return retval;
}
int
vnode_writecount(vnode_t vp)
{
return vp->v_writecount;
}
/* is vnode_t in use by others? */
int
vnode_isinuse(vnode_t vp, int refcnt)
{
return vnode_isinuse_locked(vp, refcnt, 0);
}
int
vnode_usecount(vnode_t vp)
{
return vp->v_usecount;
}
int
vnode_iocount(vnode_t vp)
{
return vp->v_iocount;
}
int
vnode_isinuse_locked(vnode_t vp, int refcnt, int locked)
{
int retval = 0;
if (!locked) {
vnode_lock_spin(vp);
}
if ((vp->v_type != VREG) && ((vp->v_usecount - vp->v_kusecount) > refcnt)) {
retval = 1;
goto out;
}
if (vp->v_type == VREG) {
retval = ubc_isinuse_locked(vp, refcnt, 1);
}
out:
if (!locked) {
vnode_unlock(vp);
}
return retval;
}
kauth_cred_t
vnode_cred(vnode_t vp)
{
if (vp->v_cred) {
return kauth_cred_require(vp->v_cred);
}
return NULL;
}
/* resume vnode_t */
errno_t
vnode_resume(vnode_t vp)
{
if ((vp->v_lflag & VL_SUSPENDED) && vp->v_owner == current_thread()) {
vnode_lock_spin(vp);
vp->v_lflag &= ~VL_SUSPENDED;
vp->v_owner = NULL;
vnode_unlock(vp);
wakeup(&vp->v_iocount);
}
return 0;
}
/* suspend vnode_t
* Please do not use on more than one vnode at a time as it may
* cause deadlocks.
* xxx should we explicity prevent this from happening?
*/
errno_t
vnode_suspend(vnode_t vp)
{
if (vp->v_lflag & VL_SUSPENDED) {
return EBUSY;
}
vnode_lock_spin(vp);
/*
* xxx is this sufficient to check if a vnode_drain is
* progress?
*/
if (vp->v_owner == NULL) {
vp->v_lflag |= VL_SUSPENDED;
vp->v_owner = current_thread();
}
vnode_unlock(vp);
return 0;
}
/*
* Release any blocked locking requests on the vnode.
* Used for forced-unmounts.
*
* XXX What about network filesystems?
*/
static void
vnode_abort_advlocks(vnode_t vp)
{
if (vp->v_flag & VLOCKLOCAL) {
lf_abort_advlocks(vp);
}
}
static errno_t
vnode_drain(vnode_t vp)
{
if (vp->v_lflag & VL_DRAIN) {
panic("vnode_drain: recursive drain");
return ENOENT;
}
vp->v_lflag |= VL_DRAIN;
vp->v_owner = current_thread();
while (vp->v_iocount > 1) {
if (bootarg_no_vnode_drain) {
struct timespec ts = {.tv_sec = 10, .tv_nsec = 0};
int error;
if (vfs_unmountall_started) {
ts.tv_sec = 1;
}
error = msleep(&vp->v_iocount, &vp->v_lock, PVFS, "vnode_drain_with_timeout", &ts);
/* Try to deal with leaked iocounts under bootarg and shutting down */
if (vp->v_iocount > 1 && error == EWOULDBLOCK &&
ts.tv_sec == 1 && vp->v_numoutput == 0) {
vp->v_iocount = 1;
break;
}
} else {
msleep(&vp->v_iocount, &vp->v_lock, PVFS, "vnode_drain", NULL);
}
}
vp->v_lflag &= ~VL_DRAIN;
return 0;
}
/*
* if the number of recent references via vnode_getwithvid or vnode_getwithref
* exceeds this threshold, than 'UN-AGE' the vnode by removing it from
* the LRU list if it's currently on it... once the iocount and usecount both drop
* to 0, it will get put back on the end of the list, effectively making it younger
* this allows us to keep actively referenced vnodes in the list without having
* to constantly remove and add to the list each time a vnode w/o a usecount is
* referenced which costs us taking and dropping a global lock twice.
* However, if the vnode is marked DIRTY, we want to pull it out much earlier
*/
#define UNAGE_THRESHHOLD 25
#define UNAGE_DIRTYTHRESHHOLD 6
errno_t
vnode_getiocount(vnode_t vp, unsigned int vid, int vflags)
{
int nodead = vflags & VNODE_NODEAD;
int nosusp = vflags & VNODE_NOSUSPEND;
int always = vflags & VNODE_ALWAYS;
int beatdrain = vflags & VNODE_DRAINO;
int withvid = vflags & VNODE_WITHID;
int forpager = vflags & VNODE_PAGER;
int noblock = vflags & VNODE_NOBLOCK;
for (;;) {
int sleepflg = 0;
/*
* if it is a dead vnode with deadfs
*/
if (nodead && (vp->v_lflag & VL_DEAD) && ((vp->v_type == VBAD) || (vp->v_data == 0))) {
return ENOENT;
}
/*
* will return VL_DEAD ones
*/
if ((vp->v_lflag & (VL_SUSPENDED | VL_DRAIN | VL_TERMINATE)) == 0) {
break;
}
/*
* if suspended vnodes are to be failed
*/
if (nosusp && (vp->v_lflag & VL_SUSPENDED)) {
return ENOENT;
}
/*
* if you are the owner of drain/suspend/termination , can acquire iocount
* check for VL_TERMINATE; it does not set owner
*/
if ((vp->v_lflag & (VL_DRAIN | VL_SUSPENDED | VL_TERMINATE)) &&
(vp->v_owner == current_thread())) {
break;
}
if (always != 0) {
break;
}
if (noblock && (vp->v_lflag & (VL_DRAIN | VL_SUSPENDED | VL_TERMINATE))) {
return ENOENT;
}
/*
* If this vnode is getting drained, there are some cases where
* we can't block or, in case of tty vnodes, want to be
* interruptible.
*/
if (vp->v_lflag & VL_DRAIN) {
/*
* In some situations, we want to get an iocount
* even if the vnode is draining to prevent deadlock,
* e.g. if we're in the filesystem, potentially holding
* resources that could prevent other iocounts from
* being released.
*/
if (beatdrain) {
break;
}
/*
* Don't block if the vnode's mount point is unmounting as
* we may be the thread the unmount is itself waiting on
* Only callers who pass in vids (at this point, we've already
* handled nosusp and nodead) are expecting error returns
* from this function, so only we can only return errors for
* those. ENODEV is intended to inform callers that the call
* failed because an unmount is in progress.
*/
if (withvid && (vp->v_mount) && vfs_isunmount(vp->v_mount)) {
return ENODEV;
}
if (vnode_istty(vp)) {
sleepflg = PCATCH;
}
}
vnode_lock_convert(vp);
if (vp->v_lflag & VL_TERMINATE) {
int error;
vp->v_lflag |= VL_TERMWANT;
error = msleep(&vp->v_lflag, &vp->v_lock,
(PVFS | sleepflg), "vnode getiocount", NULL);
if (error) {
return error;
}
} else {
msleep(&vp->v_iocount, &vp->v_lock, PVFS, "vnode_getiocount", NULL);
}
}
if (withvid && vid != vp->v_id) {
return ENOENT;
}
if (!forpager && (++vp->v_references >= UNAGE_THRESHHOLD ||
(vp->v_flag & VISDIRTY && vp->v_references >= UNAGE_DIRTYTHRESHHOLD))) {
vp->v_references = 0;
vnode_list_remove(vp);
}
vp->v_iocount++;
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
return 0;
}
static void
vnode_dropiocount(vnode_t vp)
{
if (vp->v_iocount < 1) {
panic("vnode_dropiocount(%p): v_iocount < 1", vp);
}
vp->v_iocount--;
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, -1);
#endif
if ((vp->v_lflag & (VL_DRAIN | VL_SUSPENDED)) && (vp->v_iocount <= 1)) {
wakeup(&vp->v_iocount);
}
}
void
vnode_reclaim(struct vnode * vp)
{
vnode_reclaim_internal(vp, 0, 0, 0);
}
__private_extern__
void
vnode_reclaim_internal(struct vnode * vp, int locked, int reuse, int flags)
{
int isfifo = 0;
bool clear_tty_revoke = false;
if (!locked) {
vnode_lock(vp);
}
if (vp->v_lflag & VL_TERMINATE) {
panic("vnode reclaim in progress");
}
vp->v_lflag |= VL_TERMINATE;
vn_clearunionwait(vp, 1);
/*
* We have to force any terminals in reads to return and give up
* their iocounts. It's important to do this after VL_TERMINATE
* has been set to ensure new reads are blocked while the
* revoke is in progress.
*/
if (vnode_istty(vp) && (flags & REVOKEALL) && (vp->v_iocount > 1)) {
vnode_unlock(vp);
VNOP_IOCTL(vp, TIOCREVOKE, (caddr_t)NULL, 0, vfs_context_kernel());
clear_tty_revoke = true;
vnode_lock(vp);
}
vnode_drain(vp);
if (clear_tty_revoke) {
vnode_unlock(vp);
VNOP_IOCTL(vp, TIOCREVOKECLEAR, (caddr_t)NULL, 0, vfs_context_kernel());
vnode_lock(vp);
}
#if CONFIG_FILE_LEASES
/*
* Revoke all leases in place for this vnode as it is about to be reclaimed.
* In normal case, there shouldn't be any leases in place by the time we
* get here as there shouldn't be any opens on the vnode (usecount == 0).
* However, in the case of force unmount or unmount of a volume that
* contains file that was opened with O_EVTONLY then the vnode can be
* reclaimed while the file is still opened.
*/
vnode_revokelease(vp, true);
#endif
isfifo = (vp->v_type == VFIFO);
if (vp->v_type != VBAD) {
vgone(vp, flags); /* clean and reclaim the vnode */
}
/*
* give the vnode a new identity so that vnode_getwithvid will fail
* on any stale cache accesses...
* grab the list_lock so that if we're in "new_vnode"
* behind the list_lock trying to steal this vnode, the v_id is stable...
* once new_vnode drops the list_lock, it will block trying to take
* the vnode lock until we release it... at that point it will evaluate
* whether the v_vid has changed
* also need to make sure that the vnode isn't on a list where "new_vnode"
* can find it after the v_id has been bumped until we are completely done
* with the vnode (i.e. putting it back on a list has to be the very last
* thing we do to this vnode... many of the callers of vnode_reclaim_internal
* are holding an io_count on the vnode... they need to drop the io_count
* BEFORE doing a vnode_list_add or make sure to hold the vnode lock until
* they are completely done with the vnode
*/
vnode_list_lock();
vnode_list_remove_locked(vp);
vp->v_id++;
vnode_list_unlock();
if (isfifo) {
struct fifoinfo * fip;
fip = vp->v_fifoinfo;
vp->v_fifoinfo = NULL;
kfree_type(struct fifoinfo, fip);
}
vp->v_type = VBAD;
if (vp->v_data) {
panic("vnode_reclaim_internal: cleaned vnode isn't");
}
if (vp->v_numoutput) {
panic("vnode_reclaim_internal: clean vnode has pending I/O's");
}
if (UBCINFOEXISTS(vp)) {
panic("vnode_reclaim_internal: ubcinfo not cleaned");
}
if (vp->v_parent) {
panic("vnode_reclaim_internal: vparent not removed");
}
if (vp->v_name) {
panic("vnode_reclaim_internal: vname not removed");
}
#if CONFIG_FILE_LEASES
if (__improbable(!LIST_EMPTY(&vp->v_leases))) {
panic("vnode_reclaim_internal: vleases NOT empty");
}
#endif
vp->v_socket = NULL;
vp->v_lflag &= ~VL_TERMINATE;
vp->v_owner = NULL;
#if CONFIG_IOCOUNT_TRACE
if (__improbable(bootarg_vnode_iocount_trace)) {
bzero(vp->v_iocount_trace,
IOCOUNT_TRACE_MAX_TYPES * sizeof(struct vnode_iocount_trace));
}
#endif /* CONFIG_IOCOUNT_TRACE */
KNOTE(&vp->v_knotes, NOTE_REVOKE);
/* Make sure that when we reuse the vnode, no knotes left over */
klist_init(&vp->v_knotes);
if (vp->v_lflag & VL_TERMWANT) {
vp->v_lflag &= ~VL_TERMWANT;
wakeup(&vp->v_lflag);
}
if (!reuse) {
/*
* make sure we get on the
* dead list if appropriate
*/
vnode_list_add(vp);
}
if (!locked) {
vnode_unlock(vp);
}
}
static int
vnode_create_internal(uint32_t flavor, uint32_t size, void *data, vnode_t *vpp,
vnode_create_options_t vc_options)
{
int error;
int insert = 1;
vnode_t vp = NULLVP;
vnode_t nvp;
vnode_t dvp;
struct uthread *ut;
struct componentname *cnp;
struct vnode_fsparam *param = (struct vnode_fsparam *)data;
#if CONFIG_TRIGGERS
struct vnode_trigger_param *tinfo = NULL;
#endif
bool existing_vnode;
bool init_vnode = !(vc_options & VNODE_CREATE_EMPTY);
bool is_bdevvp = false;
if (*vpp) {
vp = *vpp;
*vpp = NULLVP;
existing_vnode = true;
} else {
existing_vnode = false;
}
if (init_vnode) {
/* Do quick sanity check on the parameters. */
if ((param == NULL) || (param->vnfs_vtype == VBAD)) {
error = EINVAL;
goto error_out;
}
#if CONFIG_TRIGGERS
if ((flavor == VNCREATE_TRIGGER) && (size == VNCREATE_TRIGGER_SIZE)) {
tinfo = (struct vnode_trigger_param *)data;
/* Validate trigger vnode input */
if ((param->vnfs_vtype != VDIR) ||
(tinfo->vnt_resolve_func == NULL) ||
(tinfo->vnt_flags & ~VNT_VALID_MASK)) {
error = EINVAL;
goto error_out;
}
/* Fall through a normal create (params will be the same) */
flavor = VNCREATE_FLAVOR;
size = VCREATESIZE;
}
#endif
if ((flavor != VNCREATE_FLAVOR) || (size != VCREATESIZE)) {
error = EINVAL;
goto error_out;
}
}
if (!existing_vnode) {
if ((error = new_vnode(&vp, !(vc_options & VNODE_CREATE_NODEALLOC)))) {
return error;
}
if (!init_vnode) {
/* Make it so that it can be released by a vnode_put) */
vnode_lock(vp);
vn_set_dead(vp);
vnode_unlock(vp);
*vpp = vp;
return 0;
}
} else {
/*
* A vnode obtained by vnode_create_empty has been passed to
* vnode_initialize - Unset VL_DEAD set by vn_set_dead. After
* this point, it is set back on any error.
*/
vnode_lock(vp);
vp->v_lflag &= ~VL_DEAD;
vnode_unlock(vp);
}
dvp = param->vnfs_dvp;
cnp = param->vnfs_cnp;
vp->v_op = param->vnfs_vops;
vp->v_type = (uint16_t)param->vnfs_vtype;
vp->v_data = param->vnfs_fsnode;
if (param->vnfs_markroot) {
vp->v_flag |= VROOT;
}
if (param->vnfs_marksystem) {
vp->v_flag |= VSYSTEM;
}
if (vp->v_type == VREG) {
error = ubc_info_init_withsize(vp, param->vnfs_filesize);
if (error) {
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_hold(vp);
vnode_lock(vp);
vn_set_dead(vp);
vnode_put_locked(vp);
vnode_drop_and_unlock(vp);
return error;
}
if (param->vnfs_mp->mnt_ioflags & MNT_IOFLAGS_IOSCHED_SUPPORTED) {
memory_object_mark_io_tracking(vp->v_ubcinfo->ui_control);
}
}
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
#if CONFIG_FIRMLINKS
vp->v_fmlink = NULLVP;
#endif
vp->v_flag &= ~VFMLINKTARGET;
#if CONFIG_TRIGGERS
/*
* For trigger vnodes, attach trigger info to vnode
*/
if ((vp->v_type == VDIR) && (tinfo != NULL)) {
/*
* Note: has a side effect of incrementing trigger count on the
* mount if successful, which we would need to undo on a
* subsequent failure.
*/
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, -1);
#endif
error = vnode_resolver_create(param->vnfs_mp, vp, tinfo, FALSE);
if (error) {
printf("vnode_create: vnode_resolver_create() err %d\n", error);
vnode_hold(vp);
vnode_lock(vp);
vn_set_dead(vp);
#ifdef CONFIG_IOCOUNT_TRACE
record_vp(vp, 1);
#endif
vnode_put_locked(vp);
vnode_drop_and_unlock(vp);
return error;
}
}
#endif
if (vp->v_type == VCHR || vp->v_type == VBLK) {
vp->v_tag = VT_DEVFS; /* callers will reset if needed (bdevvp) */
if ((nvp = checkalias(vp, param->vnfs_rdev))) {
/*
* if checkalias returns a vnode, it will be locked
*
* first get rid of the unneeded vnode we acquired
*/
vp->v_data = NULL;
vp->v_op = spec_vnodeop_p;
vp->v_type = VBAD;
vp->v_lflag = VL_DEAD;
vp->v_data = NULL;
vp->v_tag = VT_NON;
vnode_put(vp);
/*
* switch to aliased vnode and finish
* preparing it
*/
vp = nvp;
is_bdevvp = (vp->v_flag & VBDEVVP);
if (is_bdevvp) {
printf("%s: alias vnode (vid = %u) is in state of change (start) v_flags = 0x%x v_numoutput = %d\n",
__func__, vp->v_id, vp->v_flag, vp->v_numoutput);
}
vnode_hold(vp);
vp->v_lflag |= VL_OPSCHANGE;
vclean(vp, 0);
vp->v_op = param->vnfs_vops;
vp->v_type = (uint16_t)param->vnfs_vtype;
vp->v_data = param->vnfs_fsnode;
vp->v_lflag = VL_OPSCHANGE;
vp->v_mount = NULL;
insmntque(vp, param->vnfs_mp);
insert = 0;
if (is_bdevvp) {
printf("%s: alias vnode (vid = %u), is in state of change (end) v_flags = 0x%x v_numoutput = %d\n",
__func__, vp->v_id, vp->v_flag, vp->v_numoutput);
}
vnode_drop_and_unlock(vp);
wakeup(&vp->v_lflag); /* chkvnlock is waitng for VL_DEAD to get unset */
}
if (VCHR == vp->v_type) {
u_int maj = major(vp->v_rdev);
if (maj < (u_int)nchrdev && cdevsw[maj].d_type == D_TTY) {
vp->v_flag |= VISTTY;
}
}
}
if (vp->v_type == VFIFO) {
struct fifoinfo *fip;
fip = kalloc_type(struct fifoinfo, Z_WAITOK | Z_ZERO);
vp->v_fifoinfo = fip;
}
/* The file systems must pass the address of the location where
* they store the vnode pointer. When we add the vnode into the mount
* list and name cache they become discoverable. So the file system node
* must have the connection to vnode setup by then
*/
*vpp = vp;
/* Add fs named reference. */
if (param->vnfs_flags & VNFS_ADDFSREF) {
vp->v_lflag |= VNAMED_FSHASH;
}
if (param->vnfs_mp) {
if (param->vnfs_mp->mnt_kern_flag & MNTK_LOCK_LOCAL) {
vp->v_flag |= VLOCKLOCAL;
}
if (insert) {
if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb)) {
panic("insmntque: vp on the free list");
}
/*
* enter in mount vnode list
*/
insmntque(vp, param->vnfs_mp);
}
}
if (dvp && vnode_ref(dvp) == 0) {
vp->v_parent = dvp;
}
if (cnp) {
if (dvp && ((param->vnfs_flags & (VNFS_NOCACHE | VNFS_CANTCACHE)) == 0)) {
/*
* enter into name cache
* we've got the info to enter it into the name cache now
* cache_enter_create will pick up an extra reference on
* the name entered into the string cache
*/
vp->v_name = cache_enter_create(dvp, vp, cnp);
} else {
vp->v_name = vfs_addname(cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_hash, 0);
}
if ((cnp->cn_flags & UNIONCREATED) == UNIONCREATED) {
vp->v_flag |= VISUNION;
}
}
if ((param->vnfs_flags & VNFS_CANTCACHE) == 0) {
/*
* this vnode is being created as cacheable in the name cache
* this allows us to re-enter it in the cache
*/
vp->v_flag |= VNCACHEABLE;
}
ut = current_uthread();
if ((current_proc()->p_lflag & P_LRAGE_VNODES) ||
(ut->uu_flag & (UT_RAGE_VNODES | UT_KERN_RAGE_VNODES))) {
/*
* process has indicated that it wants any
* vnodes created on its behalf to be rapidly
* aged to reduce the impact on the cached set
* of vnodes
*
* if UT_KERN_RAGE_VNODES is set, then the
* kernel internally wants vnodes to be rapidly
* aged, even if the process hasn't requested
* this
*/
vp->v_flag |= VRAGE;
}
#if CONFIG_SECLUDED_MEMORY
switch (secluded_for_filecache) {
case SECLUDED_FILECACHE_NONE:
/*
* secluded_for_filecache == 0:
* + no file contents in secluded pool
*/
break;
case SECLUDED_FILECACHE_APPS:
/*
* secluded_for_filecache == 1:
* + no files from /
* + files from /Applications/ are OK
* + files from /Applications/Camera are not OK
* + no files that are open for write
*/
if (vnode_vtype(vp) == VREG &&
vnode_mount(vp) != NULL &&
(!(vfs_flags(vnode_mount(vp)) & MNT_ROOTFS))) {
/* not from root filesystem: eligible for secluded pages */
memory_object_mark_eligible_for_secluded(
ubc_getobject(vp, UBC_FLAGS_NONE),
TRUE);
}
break;
case SECLUDED_FILECACHE_RDONLY:
/*
* secluded_for_filecache == 2:
* + all read-only files OK, except:
* + dyld_shared_cache_arm64*
* + Camera
* + mediaserverd
*/
if (vnode_vtype(vp) == VREG) {
memory_object_mark_eligible_for_secluded(
ubc_getobject(vp, UBC_FLAGS_NONE),
TRUE);
}
break;
default:
break;
}
#endif /* CONFIG_SECLUDED_MEMORY */
if (is_bdevvp) {
/*
* The v_flags and v_lflags felds for the vndoe above are
* manipulated without the vnode lock. This is fine for
* everything because no other use of this vnode is occurring.
* However the case of the bdevvp alias vnode reuse is different
* and the flags end up being modified while a thread may be in
* vnode_waitforwrites which sets VTHROTTLED and any one of the
* non atomic modifications of v_flag in this function can race
* with the setting of that flag and cause VTHROTTLED on vflag
* to get "lost".
*
* This should ideally be fixed by making sure all modifications
* in this function to the vnode flags are done under the
* vnode lock but at this time, a much smaller workaround is
* being employed and a the more correct (and potentially
* much bigger) change will follow later.
*
* The effect of "losing" the VTHROTTLED flags would be a lost
* wakeup so we just issue that wakeup here since this happens
* only once per bdevvp vnode which are only one or two for a
* given boot.
*/
wakeup(&vp->v_numoutput);
/*
* now make sure the flags that we were suppossed to put aren't
* lost.
*/
vnode_lock_spin(vp);
if (param->vnfs_flags & VNFS_ADDFSREF) {
vp->v_lflag |= VNAMED_FSHASH;
}
if (param->vnfs_mp && (param->vnfs_mp->mnt_kern_flag & MNTK_LOCK_LOCAL)) {
vp->v_flag |= VLOCKLOCAL;
}
if ((param->vnfs_flags & VNFS_CANTCACHE) == 0) {
vp->v_flag |= VNCACHEABLE;
}
vnode_unlock(vp);
}
return 0;
error_out:
if (existing_vnode) {
vnode_put(vp);
}
return error;
}
int
vnode_create_ext(uint32_t flavor, uint32_t size, void *data, vnode_t *vpp, vnode_create_options_t vc_options)
{
if (vc_options & ~(VNODE_CREATE_EMPTY | VNODE_CREATE_NODEALLOC)) {
return EINVAL;
}
*vpp = NULLVP;
return vnode_create_internal(flavor, size, data, vpp, vc_options);
}
/* USAGE:
* The following api creates a vnode and associates all the parameter specified in vnode_fsparam
* structure and returns a vnode handle with a reference. device aliasing is handled here so checkalias
* is obsoleted by this.
*/
int
vnode_create(uint32_t flavor, uint32_t size, void *data, vnode_t *vpp)
{
return vnode_create_ext(flavor, size, data, vpp, VNODE_CREATE_NODEALLOC);
}
int
vnode_create_empty(vnode_t *vpp)
{
return vnode_create_ext(VNCREATE_FLAVOR, VCREATESIZE, NULL,
vpp, VNODE_CREATE_EMPTY);
}
int
vnode_initialize(uint32_t __unused flavor, uint32_t size, void *data, vnode_t *vpp)
{
if (*vpp == NULLVP) {
panic("NULL vnode passed to vnode_initialize");
}
#if DEVELOPMENT || DEBUG
/*
* We lock to check that vnode is fit for unlocked use in
* vnode_create_internal.
*/
vnode_lock_spin(*vpp);
VNASSERT(((*vpp)->v_iocount == 1), *vpp,
("vnode_initialize : iocount not 1, is %d", (*vpp)->v_iocount));
VNASSERT(((*vpp)->v_usecount == 0), *vpp,
("vnode_initialize : usecount not 0, is %d", (*vpp)->v_usecount));
VNASSERT(((*vpp)->v_lflag & VL_DEAD), *vpp,
("vnode_initialize : v_lflag does not have VL_DEAD, is 0x%x",
(*vpp)->v_lflag));
VNASSERT(((*vpp)->v_data == NULL), *vpp,
("vnode_initialize : v_data not NULL"));
vnode_unlock(*vpp);
#endif
return vnode_create_internal(flavor, size, data, vpp, VNODE_CREATE_DEFAULT);
}
int
vnode_addfsref(vnode_t vp)
{
vnode_lock_spin(vp);
if (vp->v_lflag & VNAMED_FSHASH) {
panic("add_fsref: vp already has named reference");
}
if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb)) {
panic("addfsref: vp on the free list");
}
vp->v_lflag |= VNAMED_FSHASH;
vnode_unlock(vp);
return 0;
}
int
vnode_removefsref(vnode_t vp)
{
vnode_lock_spin(vp);
if ((vp->v_lflag & VNAMED_FSHASH) == 0) {
panic("remove_fsref: no named reference");
}
vp->v_lflag &= ~VNAMED_FSHASH;
vnode_unlock(vp);
return 0;
}
int
vfs_iterate(int flags, int (*callout)(mount_t, void *), void *arg)
{
mount_t mp;
int ret = 0;
fsid_t * fsid_list;
int count, actualcount, i;
void * allocmem;
int indx_start, indx_stop, indx_incr;
int cb_dropref = (flags & VFS_ITERATE_CB_DROPREF);
int noskip_unmount = (flags & VFS_ITERATE_NOSKIP_UNMOUNT);
count = mount_getvfscnt();
count += 10;
fsid_list = kalloc_data(count * sizeof(fsid_t), Z_WAITOK);
allocmem = (void *)fsid_list;
actualcount = mount_fillfsids(fsid_list, count);
/*
* Establish the iteration direction
* VFS_ITERATE_TAIL_FIRST overrides default head first order (oldest first)
*/
if (flags & VFS_ITERATE_TAIL_FIRST) {
indx_start = actualcount - 1;
indx_stop = -1;
indx_incr = -1;
} else { /* Head first by default */
indx_start = 0;
indx_stop = actualcount;
indx_incr = 1;
}
for (i = indx_start; i != indx_stop; i += indx_incr) {
/* obtain the mount point with iteration reference */
mp = mount_list_lookupby_fsid(&fsid_list[i], 0, 1);
if (mp == (struct mount *)0) {
continue;
}
mount_lock(mp);
if ((mp->mnt_lflag & MNT_LDEAD) ||
(!noskip_unmount && (mp->mnt_lflag & MNT_LUNMOUNT))) {
mount_unlock(mp);
mount_iterdrop(mp);
continue;
}
mount_unlock(mp);
/* iterate over all the vnodes */
ret = callout(mp, arg);
/*
* Drop the iterref here if the callback didn't do it.
* Note: If cb_dropref is set the mp may no longer exist.
*/
if (!cb_dropref) {
mount_iterdrop(mp);
}
switch (ret) {
case VFS_RETURNED:
case VFS_RETURNED_DONE:
if (ret == VFS_RETURNED_DONE) {
ret = 0;
goto out;
}
break;
case VFS_CLAIMED_DONE:
ret = 0;
goto out;
case VFS_CLAIMED:
default:
break;
}
ret = 0;
}
out:
kfree_data(allocmem, count * sizeof(fsid_t));
return ret;
}
/*
* Update the vfsstatfs structure in the mountpoint.
* MAC: Parameter eventtype added, indicating whether the event that
* triggered this update came from user space, via a system call
* (VFS_USER_EVENT) or an internal kernel call (VFS_KERNEL_EVENT).
*/
int
vfs_update_vfsstat(mount_t mp, vfs_context_t ctx, __unused int eventtype)
{
struct vfs_attr va;
int error;
/*
* Request the attributes we want to propagate into
* the per-mount vfsstat structure.
*/
VFSATTR_INIT(&va);
VFSATTR_WANTED(&va, f_iosize);
VFSATTR_WANTED(&va, f_blocks);
VFSATTR_WANTED(&va, f_bfree);
VFSATTR_WANTED(&va, f_bavail);
VFSATTR_WANTED(&va, f_bused);
VFSATTR_WANTED(&va, f_files);
VFSATTR_WANTED(&va, f_ffree);
VFSATTR_WANTED(&va, f_bsize);
VFSATTR_WANTED(&va, f_fssubtype);
if ((error = vfs_getattr(mp, &va, ctx)) != 0) {
KAUTH_DEBUG("STAT - filesystem returned error %d", error);
return error;
}
#if CONFIG_MACF
if (eventtype == VFS_USER_EVENT) {
error = mac_mount_check_getattr(ctx, mp, &va);
if (error != 0) {
return error;
}
}
#endif
/*
* Unpack into the per-mount structure.
*
* We only overwrite these fields, which are likely to change:
* f_blocks
* f_bfree
* f_bavail
* f_bused
* f_files
* f_ffree
*
* And these which are not, but which the FS has no other way
* of providing to us:
* f_bsize
* f_iosize
* f_fssubtype
*
*/
if (VFSATTR_IS_SUPPORTED(&va, f_bsize)) {
/* 4822056 - protect against malformed server mount */
mp->mnt_vfsstat.f_bsize = (va.f_bsize > 0 ? va.f_bsize : 512);
} else {
mp->mnt_vfsstat.f_bsize = mp->mnt_devblocksize; /* default from the device block size */
}
if (VFSATTR_IS_SUPPORTED(&va, f_iosize)) {
mp->mnt_vfsstat.f_iosize = va.f_iosize;
} else {
mp->mnt_vfsstat.f_iosize = 1024 * 1024; /* 1MB sensible I/O size */
}
if (VFSATTR_IS_SUPPORTED(&va, f_blocks)) {
mp->mnt_vfsstat.f_blocks = va.f_blocks;
}
if (VFSATTR_IS_SUPPORTED(&va, f_bfree)) {
mp->mnt_vfsstat.f_bfree = va.f_bfree;
}
if (VFSATTR_IS_SUPPORTED(&va, f_bavail)) {
mp->mnt_vfsstat.f_bavail = va.f_bavail;
}
if (VFSATTR_IS_SUPPORTED(&va, f_bused)) {
mp->mnt_vfsstat.f_bused = va.f_bused;
}
if (VFSATTR_IS_SUPPORTED(&va, f_files)) {
mp->mnt_vfsstat.f_files = va.f_files;
}
if (VFSATTR_IS_SUPPORTED(&va, f_ffree)) {
mp->mnt_vfsstat.f_ffree = va.f_ffree;
}
/* this is unlikely to change, but has to be queried for */
if (VFSATTR_IS_SUPPORTED(&va, f_fssubtype)) {
mp->mnt_vfsstat.f_fssubtype = va.f_fssubtype;
}
return 0;
}
int
mount_list_add(mount_t mp)
{
int res;
mount_list_lock();
if (get_system_inshutdown() != 0) {
res = -1;
} else {
TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
nummounts++;
res = 0;
}
mount_list_unlock();
return res;
}
void
mount_list_remove(mount_t mp)
{
mount_list_lock();
TAILQ_REMOVE(&mountlist, mp, mnt_list);
nummounts--;
mp->mnt_list.tqe_next = NULL;
mp->mnt_list.tqe_prev = NULL;
mount_list_unlock();
}
mount_t
mount_lookupby_volfsid(int volfs_id, int withref)
{
mount_t cur_mount = (mount_t)0;
mount_t mp;
mount_list_lock();
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
if (!(mp->mnt_kern_flag & MNTK_UNMOUNT) &&
(mp->mnt_kern_flag & MNTK_PATH_FROM_ID) &&
(mp->mnt_vfsstat.f_fsid.val[0] == volfs_id)) {
cur_mount = mp;
if (withref) {
if (mount_iterref(cur_mount, 1)) {
cur_mount = (mount_t)0;
mount_list_unlock();
goto out;
}
}
break;
}
}
mount_list_unlock();
if (withref && (cur_mount != (mount_t)0)) {
mp = cur_mount;
if (vfs_busy(mp, LK_NOWAIT) != 0) {
cur_mount = (mount_t)0;
}
mount_iterdrop(mp);
}
out:
return cur_mount;
}
mount_t
mount_list_lookupby_fsid(fsid_t *fsid, int locked, int withref)
{
mount_t retmp = (mount_t)0;
mount_t mp;
if (!locked) {
mount_list_lock();
}
TAILQ_FOREACH(mp, &mountlist, mnt_list)
if (mp->mnt_vfsstat.f_fsid.val[0] == fsid->val[0] &&
mp->mnt_vfsstat.f_fsid.val[1] == fsid->val[1]) {
retmp = mp;
if (withref) {
if (mount_iterref(retmp, 1)) {
retmp = (mount_t)0;
}
}
goto out;
}
out:
if (!locked) {
mount_list_unlock();
}
return retmp;
}
errno_t
vnode_lookupat(const char *path, int flags, vnode_t *vpp, vfs_context_t ctx,
vnode_t start_dvp)
{
struct nameidata *ndp;
int error = 0;
u_int32_t ndflags = 0;
if (ctx == NULL) {
return EINVAL;
}
ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_NOFAIL);
if (flags & VNODE_LOOKUP_NOFOLLOW) {
ndflags = NOFOLLOW;
} else {
ndflags = FOLLOW;
}
if (flags & VNODE_LOOKUP_NOCROSSMOUNT) {
ndflags |= NOCROSSMOUNT;
}
if (flags & VNODE_LOOKUP_CROSSMOUNTNOWAIT) {
ndflags |= CN_NBMOUNTLOOK;
}
/* XXX AUDITVNPATH1 needed ? */
NDINIT(ndp, LOOKUP, OP_LOOKUP, ndflags, UIO_SYSSPACE,
CAST_USER_ADDR_T(path), ctx);
if (start_dvp && (path[0] != '/')) {
ndp->ni_dvp = start_dvp;
ndp->ni_cnd.cn_flags |= USEDVP;
}
if ((error = namei(ndp))) {
goto out_free;
}
ndp->ni_cnd.cn_flags &= ~USEDVP;
*vpp = ndp->ni_vp;
nameidone(ndp);
out_free:
kfree_type(struct nameidata, ndp);
return error;
}
errno_t
vnode_lookup(const char *path, int flags, vnode_t *vpp, vfs_context_t ctx)
{
return vnode_lookupat(path, flags, vpp, ctx, NULLVP);
}
errno_t
vnode_open(const char *path, int fmode, int cmode, int flags, vnode_t *vpp, vfs_context_t ctx)
{
struct nameidata *ndp = NULL;
int error;
u_int32_t ndflags = 0;
int lflags = flags;
if (ctx == NULL) { /* XXX technically an error */
ctx = vfs_context_current();
}
ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_NOFAIL);
if (fmode & O_NOFOLLOW) {
lflags |= VNODE_LOOKUP_NOFOLLOW;
}
if (lflags & VNODE_LOOKUP_NOFOLLOW) {
ndflags = NOFOLLOW;
} else {
ndflags = FOLLOW;
}
if (lflags & VNODE_LOOKUP_NOCROSSMOUNT) {
ndflags |= NOCROSSMOUNT;
}
if (lflags & VNODE_LOOKUP_CROSSMOUNTNOWAIT) {
ndflags |= CN_NBMOUNTLOOK;
}
/* XXX AUDITVNPATH1 needed ? */
NDINIT(ndp, LOOKUP, OP_OPEN, ndflags, UIO_SYSSPACE,
CAST_USER_ADDR_T(path), ctx);
if ((error = vn_open(ndp, fmode, cmode))) {
*vpp = NULL;
} else {
*vpp = ndp->ni_vp;
}
kfree_type(struct nameidata, ndp);
return error;
}
errno_t
vnode_close(vnode_t vp, int flags, vfs_context_t ctx)
{
int error;
if (ctx == NULL) {
ctx = vfs_context_current();
}
error = vn_close(vp, flags, ctx);
vnode_put(vp);
return error;
}
errno_t
vnode_mtime(vnode_t vp, struct timespec *mtime, vfs_context_t ctx)
{
struct vnode_attr va;
int error;
VATTR_INIT(&va);
VATTR_WANTED(&va, va_modify_time);
error = vnode_getattr(vp, &va, ctx);
if (!error) {
*mtime = va.va_modify_time;
}
return error;
}
errno_t
vnode_flags(vnode_t vp, uint32_t *flags, vfs_context_t ctx)
{
struct vnode_attr va;
int error;
VATTR_INIT(&va);
VATTR_WANTED(&va, va_flags);
error = vnode_getattr(vp, &va, ctx);
if (!error) {
*flags = va.va_flags;
}
return error;
}
/*
* Returns: 0 Success
* vnode_getattr:???
*/
errno_t
vnode_size(vnode_t vp, off_t *sizep, vfs_context_t ctx)
{
struct vnode_attr va;
int error;
VATTR_INIT(&va);
VATTR_WANTED(&va, va_data_size);
error = vnode_getattr(vp, &va, ctx);
if (!error) {
*sizep = va.va_data_size;
}
return error;
}
errno_t
vnode_setsize(vnode_t vp, off_t size, int ioflag, vfs_context_t ctx)
{
struct vnode_attr va;
VATTR_INIT(&va);
VATTR_SET(&va, va_data_size, size);
va.va_vaflags = ioflag & 0xffff;
return vnode_setattr(vp, &va, ctx);
}
int
vnode_setdirty(vnode_t vp)
{
vnode_lock_spin(vp);
vp->v_flag |= VISDIRTY;
vnode_unlock(vp);
return 0;
}
int
vnode_cleardirty(vnode_t vp)
{
vnode_lock_spin(vp);
vp->v_flag &= ~VISDIRTY;
vnode_unlock(vp);
return 0;
}
int
vnode_isdirty(vnode_t vp)
{
int dirty;
vnode_lock_spin(vp);
dirty = (vp->v_flag & VISDIRTY) ? 1 : 0;
vnode_unlock(vp);
return dirty;
}
static int
vn_create_reg(vnode_t dvp, vnode_t *vpp, struct nameidata *ndp, struct vnode_attr *vap, uint32_t flags, int fmode, uint32_t *statusp, vfs_context_t ctx)
{
/* Only use compound VNOP for compound operation */
if (vnode_compound_open_available(dvp) && ((flags & VN_CREATE_DOOPEN) != 0)) {
*vpp = NULLVP;
return VNOP_COMPOUND_OPEN(dvp, vpp, ndp, O_CREAT, fmode, statusp, vap, ctx);
} else {
return VNOP_CREATE(dvp, vpp, &ndp->ni_cnd, vap, ctx);
}
}
/*
* Create a filesystem object of arbitrary type with arbitrary attributes in
* the spevied directory with the specified name.
*
* Parameters: dvp Pointer to the vnode of the directory
* in which to create the object.
* vpp Pointer to the area into which to
* return the vnode of the created object.
* cnp Component name pointer from the namei
* data structure, containing the name to
* use for the create object.
* vap Pointer to the vnode_attr structure
* describing the object to be created,
* including the type of object.
* flags VN_* flags controlling ACL inheritance
* and whether or not authorization is to
* be required for the operation.
*
* Returns: 0 Success
* !0 errno value
*
* Implicit: *vpp Contains the vnode of the object that
* was created, if successful.
* *cnp May be modified by the underlying VFS.
* *vap May be modified by the underlying VFS.
* modified by either ACL inheritance or
*
*
* be modified, even if the operation is
*
*
* Notes: The kauth_filesec_t in 'vap', if any, is in host byte order.
*
* Modification of '*cnp' and '*vap' by the underlying VFS is
* strongly discouraged.
*
* XXX: This function is a 'vn_*' function; it belongs in vfs_vnops.c
*
* XXX: We should enummerate the possible errno values here, and where
* in the code they originated.
*/
errno_t
vn_create(vnode_t dvp, vnode_t *vpp, struct nameidata *ndp, struct vnode_attr *vap, uint32_t flags, int fmode, uint32_t *statusp, vfs_context_t ctx)
{
errno_t error, old_error;
vnode_t vp = (vnode_t)0;
boolean_t batched;
struct componentname *cnp;
uint32_t defaulted;
cnp = &ndp->ni_cnd;
error = 0;
batched = namei_compound_available(dvp, ndp) ? TRUE : FALSE;
KAUTH_DEBUG("%p CREATE - '%s'", dvp, cnp->cn_nameptr);
if (flags & VN_CREATE_NOINHERIT) {
vap->va_vaflags |= VA_NOINHERIT;
}
if (flags & VN_CREATE_NOAUTH) {
vap->va_vaflags |= VA_NOAUTH;
}
/*
* Handle ACL inheritance, initialize vap.
*/
error = vn_attribute_prepare(dvp, vap, &defaulted, ctx);
if (error) {
return error;
}
if (vap->va_type != VREG && (fmode != 0 || (flags & VN_CREATE_DOOPEN) || statusp)) {
panic("Open parameters, but not a regular file.");
}
if ((fmode != 0) && ((flags & VN_CREATE_DOOPEN) == 0)) {
panic("Mode for open, but not trying to open...");
}
/*
* Create the requested node.
*/
switch (vap->va_type) {
case VREG:
error = vn_create_reg(dvp, vpp, ndp, vap, flags, fmode, statusp, ctx);
break;
case VDIR:
error = vn_mkdir(dvp, vpp, ndp, vap, ctx);
break;
case VSOCK:
case VFIFO:
case VBLK:
case VCHR:
error = VNOP_MKNOD(dvp, vpp, cnp, vap, ctx);
break;
default:
panic("vnode_create: unknown vtype %d", vap->va_type);
}
if (error != 0) {
KAUTH_DEBUG("%p CREATE - error %d returned by filesystem", dvp, error);
goto out;
}
vp = *vpp;
old_error = error;
/*
* If some of the requested attributes weren't handled by the VNOP,
* use our fallback code.
*/
if ((error == 0) && !VATTR_ALL_SUPPORTED(vap) && *vpp) {
KAUTH_DEBUG(" CREATE - doing fallback with ACL %p", vap->va_acl);
error = vnode_setattr_fallback(*vpp, vap, ctx);
}
#if CONFIG_MACF
if ((error == 0) && !(flags & VN_CREATE_NOLABEL)) {
error = vnode_label(vnode_mount(vp), dvp, vp, cnp, VNODE_LABEL_CREATE, ctx);
}
#endif
if ((error != 0) && (vp != (vnode_t)0)) {
/* If we've done a compound open, close */
if (batched && (old_error == 0) && (vap->va_type == VREG)) {
VNOP_CLOSE(vp, fmode, ctx);
}
/* Need to provide notifications if a create succeeded */
if (!batched) {
*vpp = (vnode_t) 0;
vnode_put(vp);
vp = NULLVP;
}
}
/*
* For creation VNOPs, this is the equivalent of
* lookup_handle_found_vnode.
*/
if (kdebug_enable && *vpp) {
kdebug_lookup(*vpp, cnp);
}
out:
vn_attribute_cleanup(vap, defaulted);
return error;
}
static kauth_scope_t vnode_scope;
static int vnode_authorize_callback(kauth_cred_t credential, void *idata, kauth_action_t action,
uintptr_t arg0, uintptr_t arg1, uintptr_t arg2, uintptr_t arg3);
static int vnode_authorize_callback_int(kauth_action_t action, vfs_context_t ctx,
vnode_t vp, vnode_t dvp, int *errorp);
typedef struct _vnode_authorize_context {
vnode_t vp;
struct vnode_attr *vap;
vnode_t dvp;
struct vnode_attr *dvap;
vfs_context_t ctx;
int flags;
int flags_valid;
#define _VAC_IS_OWNER (1<<0)
#define _VAC_IN_GROUP (1<<1)
#define _VAC_IS_DIR_OWNER (1<<2)
#define _VAC_IN_DIR_GROUP (1<<3)
#define _VAC_NO_VNODE_POINTERS (1<<4)
} *vauth_ctx;
void
vnode_authorize_init(void)
{
vnode_scope = kauth_register_scope(KAUTH_SCOPE_VNODE, vnode_authorize_callback, NULL);
}
#define VATTR_PREPARE_DEFAULTED_UID 0x1
#define VATTR_PREPARE_DEFAULTED_GID 0x2
#define VATTR_PREPARE_DEFAULTED_MODE 0x4
int
vn_attribute_prepare(vnode_t dvp, struct vnode_attr *vap, uint32_t *defaulted_fieldsp, vfs_context_t ctx)
{
kauth_acl_t nacl = NULL, oacl = NULL;
int error;
/*
* Handle ACL inheritance.
*/
if (!(vap->va_vaflags & VA_NOINHERIT) && vfs_extendedsecurity(dvp->v_mount)) {
/* save the original filesec */
if (VATTR_IS_ACTIVE(vap, va_acl)) {
oacl = vap->va_acl;
}
vap->va_acl = NULL;
if ((error = kauth_acl_inherit(dvp,
oacl,
&nacl,
vap->va_type == VDIR,
ctx)) != 0) {
KAUTH_DEBUG("%p CREATE - error %d processing inheritance", dvp, error);
return error;
}
/*
* If the generated ACL is NULL, then we can save ourselves some effort
* by clearing the active bit.
*/
if (nacl == NULL) {
VATTR_CLEAR_ACTIVE(vap, va_acl);
} else {
vap->va_base_acl = oacl;
VATTR_SET(vap, va_acl, nacl);
}
}
error = vnode_authattr_new_internal(dvp, vap, (vap->va_vaflags & VA_NOAUTH), defaulted_fieldsp, ctx);
if (error) {
vn_attribute_cleanup(vap, *defaulted_fieldsp);
}
return error;
}
void
vn_attribute_cleanup(struct vnode_attr *vap, uint32_t defaulted_fields)
{
/*
* If the caller supplied a filesec in vap, it has been replaced
* now by the post-inheritance copy. We need to put the original back
* and free the inherited product.
*/
kauth_acl_t nacl, oacl;
if (VATTR_IS_ACTIVE(vap, va_acl)) {
nacl = vap->va_acl;
oacl = vap->va_base_acl;
if (oacl) {
VATTR_SET(vap, va_acl, oacl);
vap->va_base_acl = NULL;
} else {
VATTR_CLEAR_ACTIVE(vap, va_acl);
}
if (nacl != NULL) {
/*
* Only free the ACL buffer if 'VA_FILESEC_ACL' is not set as it
* should be freed by the caller or it is a post-inheritance copy.
*/
if (!(vap->va_vaflags & VA_FILESEC_ACL) ||
(oacl != NULL && nacl != oacl)) {
kauth_acl_free(nacl);
}
}
}
if ((defaulted_fields & VATTR_PREPARE_DEFAULTED_MODE) != 0) {
VATTR_CLEAR_ACTIVE(vap, va_mode);
}
if ((defaulted_fields & VATTR_PREPARE_DEFAULTED_GID) != 0) {
VATTR_CLEAR_ACTIVE(vap, va_gid);
}
if ((defaulted_fields & VATTR_PREPARE_DEFAULTED_UID) != 0) {
VATTR_CLEAR_ACTIVE(vap, va_uid);
}
return;
}
int
vn_authorize_unlink(vnode_t dvp, vnode_t vp, struct componentname *cnp, vfs_context_t ctx, __unused void *reserved)
{
#if !CONFIG_MACF
#pragma unused(cnp)
#endif
int error = 0;
/*
* Normally, unlinking of directories is not supported.
* However, some file systems may have limited support.
*/
if ((vp->v_type == VDIR) &&
!(vp->v_mount->mnt_kern_flag & MNTK_DIR_HARDLINKS)) {
return EPERM; /* POSIX */
}
/* authorize the delete operation */
#if CONFIG_MACF
if (!error) {
error = mac_vnode_check_unlink(ctx, dvp, vp, cnp);
}
#endif /* MAC */
if (!error) {
error = vnode_authorize(vp, dvp, KAUTH_VNODE_DELETE, ctx);
}
return error;
}
int
vn_authorize_open_existing(vnode_t vp, struct componentname *cnp, int fmode, vfs_context_t ctx, void *reserved)
{
/* Open of existing case */
kauth_action_t action;
int error = 0;
if (cnp->cn_ndp == NULL) {
panic("NULL ndp");
}
if (reserved != NULL) {
panic("reserved not NULL.");
}
#if CONFIG_MACF
/* XXX may do duplicate work here, but ignore that for now (idempotent) */
if (vfs_flags(vnode_mount(vp)) & MNT_MULTILABEL) {
error = vnode_label(vnode_mount(vp), NULL, vp, NULL, 0, ctx);
if (error) {
return error;
}
}
#endif
if (vnode_isdir(vp)) {
if ((fmode & (FWRITE | O_TRUNC)) || /* disallow write operations on directories */
((fmode & FSEARCH) && !(fmode & O_DIRECTORY))) {
return EISDIR;
}
} else {
if (fmode & O_DIRECTORY) {
return ENOTDIR;
}
if (vp->v_type == VSOCK && vp->v_tag != VT_FDESC) {
return EOPNOTSUPP; /* Operation not supported on socket */
}
if (vp->v_type == VLNK && (fmode & O_NOFOLLOW) != 0) {
return ELOOP; /* O_NOFOLLOW was specified and the target is a symbolic link */
}
if (cnp->cn_ndp->ni_flag & NAMEI_TRAILINGSLASH) {
return ENOTDIR;
}
if (!vnode_isreg(vp) && (fmode & FEXEC)) {
return EACCES;
}
}
#if CONFIG_MACF
/* If a file being opened is a shadow file containing
* namedstream data, ignore the macf checks because it
* is a kernel internal file and access should always
* be allowed.
*/
if (!(vnode_isshadow(vp) && vnode_isnamedstream(vp))) {
error = mac_vnode_check_open(ctx, vp, fmode);
if (error) {
return error;
}
}
#endif
/* compute action to be authorized */
action = 0;
if (fmode & FREAD) {
action |= KAUTH_VNODE_READ_DATA;
}
if (fmode & (FWRITE | O_TRUNC)) {
/*
* If we are writing, appending, and not truncating,
* indicate that we are appending so that if the
* UF_APPEND or SF_APPEND bits are set, we do not deny
* the open.
*/
if ((fmode & O_APPEND) && !(fmode & O_TRUNC)) {
action |= KAUTH_VNODE_APPEND_DATA;
} else {
action |= KAUTH_VNODE_WRITE_DATA;
}
}
if (fmode & (FSEARCH | FEXEC)) {
if (vnode_isdir(vp)) {
action |= KAUTH_VNODE_SEARCH;
} else {
action |= KAUTH_VNODE_EXECUTE;
}
}
error = vnode_authorize(vp, NULL, action, ctx);
#if NAMEDSTREAMS
if (error == EACCES) {
/*
* Shadow files may exist on-disk with a different UID/GID
* than that of the current context. Verify that this file
* is really a shadow file. If it was created successfully
* then it should be authorized.
*/
if (vnode_isshadow(vp) && vnode_isnamedstream(vp)) {
error = vnode_verifynamedstream(vp);
}
}
#endif
return error;
}
int
vn_authorize_create(vnode_t dvp, struct componentname *cnp, struct vnode_attr *vap, vfs_context_t ctx, void *reserved)
{
#if !CONFIG_MACF
#pragma unused(vap)
#endif
/* Creation case */
int error;
if (cnp->cn_ndp == NULL) {
panic("NULL cn_ndp");
}
if (reserved != NULL) {
panic("reserved not NULL.");
}
/* Only validate path for creation if we didn't do a complete lookup */
if (cnp->cn_ndp->ni_flag & NAMEI_UNFINISHED) {
error = lookup_validate_creation_path(cnp->cn_ndp);
if (error) {
return error;
}
}
#if CONFIG_MACF
error = mac_vnode_check_create(ctx, dvp, cnp, vap);
if (error) {
return error;
}
#endif /* CONFIG_MACF */
return vnode_authorize(dvp, NULL, KAUTH_VNODE_ADD_FILE, ctx);
}
int
vn_authorize_rename(struct vnode *fdvp, struct vnode *fvp, struct componentname *fcnp,
struct vnode *tdvp, struct vnode *tvp, struct componentname *tcnp,
vfs_context_t ctx, void *reserved)
{
return vn_authorize_renamex(fdvp, fvp, fcnp, tdvp, tvp, tcnp, ctx, 0, reserved);
}
int
vn_authorize_renamex(struct vnode *fdvp, struct vnode *fvp, struct componentname *fcnp,
struct vnode *tdvp, struct vnode *tvp, struct componentname *tcnp,
vfs_context_t ctx, vfs_rename_flags_t flags, void *reserved)
{
return vn_authorize_renamex_with_paths(fdvp, fvp, fcnp, NULL, tdvp, tvp, tcnp, NULL, ctx, flags, reserved);
}
int
vn_authorize_renamex_with_paths(struct vnode *fdvp, struct vnode *fvp, struct componentname *fcnp, const char *from_path,
struct vnode *tdvp, struct vnode *tvp, struct componentname *tcnp, const char *to_path,
vfs_context_t ctx, vfs_rename_flags_t flags, void *reserved)
{
int error = 0;
int moving = 0;
bool swap = flags & VFS_RENAME_SWAP;
if (reserved != NULL) {
panic("Passed something other than NULL as reserved field!");
}
/*
* Avoid renaming "." and "..".
*
* XXX No need to check for this in the FS. We should always have the leaves
* in VFS in this case.
*/
if (fvp->v_type == VDIR &&
((fdvp == fvp) ||
(fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
((fcnp->cn_flags | tcnp->cn_flags) & ISDOTDOT))) {
error = EINVAL;
goto out;
}
if (tvp == NULLVP && vnode_compound_rename_available(tdvp)) {
error = lookup_validate_creation_path(tcnp->cn_ndp);
if (error) {
goto out;
}
}
/***** <MACF> *****/
#if CONFIG_MACF
error = mac_vnode_check_rename(ctx, fdvp, fvp, fcnp, tdvp, tvp, tcnp);
if (error) {
goto out;
}
if (swap) {
error = mac_vnode_check_rename(ctx, tdvp, tvp, tcnp, fdvp, fvp, fcnp);
if (error) {
goto out;
}
}
#endif
/***** </MACF> *****/
/***** <MiscChecks> *****/
if (tvp != NULL) {
if (!swap) {
if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
error = ENOTDIR;
goto out;
} else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
error = EISDIR;
goto out;
}
}
} else if (swap) {
/*
* Caller should have already checked this and returned
* ENOENT. If we send back ENOENT here, caller will retry
* which isn't what we want so we send back EINVAL here
* instead.
*/
error = EINVAL;
goto out;
}
if (fvp == tdvp) {
error = EINVAL;
goto out;
}
/*
* The following edge case is caught here:
* (to cannot be a descendent of from)
*
* o fdvp
* /
* /
* o fvp
* \
* \
* o tdvp
* /
* /
* o tvp
*/
if (tdvp->v_parent == fvp) {
error = EINVAL;
goto out;
}
if (swap && fdvp->v_parent == tvp) {
error = EINVAL;
goto out;
}
/***** </MiscChecks> *****/
/***** <Kauth> *****/
/*
* As part of the Kauth step, we call out to allow 3rd-party
* fileop notification of "about to rename". This is needed
* in the event that 3rd-parties need to know that the DELETE
* authorization is actually part of a rename. It's important
* that we guarantee that the DELETE call-out will always be
* made if the WILL_RENAME call-out is made. Another fileop
* call-out will be performed once the operation is completed.
* We can ignore the result of kauth_authorize_fileop().
*
* N.B. We are passing the vnode and *both* paths to each
* call; kauth_authorize_fileop() extracts the "from" path
* when posting a KAUTH_FILEOP_WILL_RENAME notification.
* As such, we only post these notifications if all of the
* information we need is provided.
*/
if (swap) {
kauth_action_t f = 0, t = 0;
/*
* Directories changing parents need ...ADD_SUBDIR... to
* permit changing ".."
*/
if (fdvp != tdvp) {
if (vnode_isdir(fvp)) {
f = KAUTH_VNODE_ADD_SUBDIRECTORY;
}
if (vnode_isdir(tvp)) {
t = KAUTH_VNODE_ADD_SUBDIRECTORY;
}
}
if (to_path != NULL) {
kauth_authorize_fileop(vfs_context_ucred(ctx),
KAUTH_FILEOP_WILL_RENAME,
(uintptr_t)fvp,
(uintptr_t)to_path);
}
error = vnode_authorize(fvp, fdvp, KAUTH_VNODE_DELETE | f, ctx);
if (error) {
goto out;
}
if (from_path != NULL) {
kauth_authorize_fileop(vfs_context_ucred(ctx),
KAUTH_FILEOP_WILL_RENAME,
(uintptr_t)tvp,
(uintptr_t)from_path);
}
error = vnode_authorize(tvp, tdvp, KAUTH_VNODE_DELETE | t, ctx);
if (error) {
goto out;
}
f = vnode_isdir(fvp) ? KAUTH_VNODE_ADD_SUBDIRECTORY : KAUTH_VNODE_ADD_FILE;
t = vnode_isdir(tvp) ? KAUTH_VNODE_ADD_SUBDIRECTORY : KAUTH_VNODE_ADD_FILE;
if (fdvp == tdvp) {
error = vnode_authorize(fdvp, NULL, f | t, ctx);
} else {
error = vnode_authorize(fdvp, NULL, t, ctx);
if (error) {
goto out;
}
error = vnode_authorize(tdvp, NULL, f, ctx);
}
if (error) {
goto out;
}
} else {
error = 0;
if ((tvp != NULL) && vnode_isdir(tvp)) {
if (tvp != fdvp) {
moving = 1;
}
} else if (tdvp != fdvp) {
moving = 1;
}
/*
* must have delete rights to remove the old name even in
* the simple case of fdvp == tdvp.
*
* If fvp is a directory, and we are changing it's parent,
* then we also need rights to rewrite its ".." entry as well.
*/
if (to_path != NULL) {
kauth_authorize_fileop(vfs_context_ucred(ctx),
KAUTH_FILEOP_WILL_RENAME,
(uintptr_t)fvp,
(uintptr_t)to_path);
}
if (vnode_isdir(fvp)) {
if ((error = vnode_authorize(fvp, fdvp, KAUTH_VNODE_DELETE | KAUTH_VNODE_ADD_SUBDIRECTORY, ctx)) != 0) {
goto out;
}
} else {
if ((error = vnode_authorize(fvp, fdvp, KAUTH_VNODE_DELETE, ctx)) != 0) {
goto out;
}
}
if (moving) {
/* moving into tdvp or tvp, must have rights to add */
if ((error = vnode_authorize(((tvp != NULL) && vnode_isdir(tvp)) ? tvp : tdvp,
NULL,
vnode_isdir(fvp) ? KAUTH_VNODE_ADD_SUBDIRECTORY : KAUTH_VNODE_ADD_FILE,
ctx)) != 0) {
goto out;
}
} else {
/* node staying in same directory, must be allowed to add new name */
if ((error = vnode_authorize(fdvp, NULL,
vnode_isdir(fvp) ? KAUTH_VNODE_ADD_SUBDIRECTORY : KAUTH_VNODE_ADD_FILE, ctx)) != 0) {
goto out;
}
}
/* overwriting tvp */
if ((tvp != NULL) && !vnode_isdir(tvp) &&
((error = vnode_authorize(tvp, tdvp, KAUTH_VNODE_DELETE, ctx)) != 0)) {
goto out;
}
}
/***** </Kauth> *****/
/* XXX more checks? */
out:
return error;
}
int
vn_authorize_mkdir(vnode_t dvp, struct componentname *cnp, struct vnode_attr *vap, vfs_context_t ctx, void *reserved)
{
#if !CONFIG_MACF
#pragma unused(vap)
#endif
int error;
if (reserved != NULL) {
panic("reserved not NULL in vn_authorize_mkdir()");
}
/* XXX A hack for now, to make shadow files work */
if (cnp->cn_ndp == NULL) {
return 0;
}
if (vnode_compound_mkdir_available(dvp)) {
error = lookup_validate_creation_path(cnp->cn_ndp);
if (error) {
goto out;
}
}
#if CONFIG_MACF
error = mac_vnode_check_create(ctx,
dvp, cnp, vap);
if (error) {
goto out;
}
#endif
/* authorize addition of a directory to the parent */
if ((error = vnode_authorize(dvp, NULL, KAUTH_VNODE_ADD_SUBDIRECTORY, ctx)) != 0) {
goto out;
}
out:
return error;
}
int
vn_authorize_rmdir(vnode_t dvp, vnode_t vp, struct componentname *cnp, vfs_context_t ctx, void *reserved)
{
#if CONFIG_MACF
int error;
#else
#pragma unused(cnp)
#endif
if (reserved != NULL) {
panic("Non-NULL reserved argument to vn_authorize_rmdir()");
}
if (vp->v_type != VDIR) {
/*
* rmdir only deals with directories
*/
return ENOTDIR;
}
if (dvp == vp) {
/*
* No rmdir "." please.
*/
return EINVAL;
}
#if CONFIG_MACF
error = mac_vnode_check_unlink(ctx, dvp,
vp, cnp);
if (error) {
return error;
}
#endif
return vnode_authorize(vp, dvp, KAUTH_VNODE_DELETE, ctx);
}
/*
* Authorizer for directory cloning. This does not use vnodes but instead
* uses prefilled vnode attributes from the filesystem.
*
* The same function is called to set up the attributes required, perform the
* authorization and cleanup (if required)
*/
int
vnode_attr_authorize_dir_clone(struct vnode_attr *vap, kauth_action_t action,
struct vnode_attr *dvap, __unused vnode_t sdvp, mount_t mp,
dir_clone_authorizer_op_t vattr_op, uint32_t flags, vfs_context_t ctx,
__unused void *reserved)
{
int error;
int is_suser = vfs_context_issuser(ctx);
if (vattr_op == OP_VATTR_SETUP) {
VATTR_INIT(vap);
/*
* When ACL inheritence is implemented, both vap->va_acl and
* dvap->va_acl will be required (even as superuser).
*/
VATTR_WANTED(vap, va_type);
VATTR_WANTED(vap, va_mode);
VATTR_WANTED(vap, va_flags);
VATTR_WANTED(vap, va_uid);
VATTR_WANTED(vap, va_gid);
if (dvap) {
VATTR_INIT(dvap);
VATTR_WANTED(dvap, va_flags);
}
if (!is_suser) {
/*
* If not superuser, we have to evaluate ACLs and
* need the target directory gid to set the initial
* gid of the new object.
*/
VATTR_WANTED(vap, va_acl);
if (dvap) {
VATTR_WANTED(dvap, va_gid);
}
} else if (dvap && (flags & VNODE_CLONEFILE_NOOWNERCOPY)) {
VATTR_WANTED(dvap, va_gid);
}
return 0;
} else if (vattr_op == OP_VATTR_CLEANUP) {
return 0; /* Nothing to do for now */
}
/* dvap isn't used for authorization */
error = vnode_attr_authorize(vap, NULL, mp, action, ctx);
if (error) {
return error;
}
/*
* vn_attribute_prepare should be able to accept attributes as well as
* vnodes but for now we do this inline.
*/
if (!is_suser || (flags & VNODE_CLONEFILE_NOOWNERCOPY)) {
/*
* If the filesystem is mounted IGNORE_OWNERSHIP and an explicit
* owner is set, that owner takes ownership of all new files.
*/
if ((mp->mnt_flag & MNT_IGNORE_OWNERSHIP) &&
(mp->mnt_fsowner != KAUTH_UID_NONE)) {
VATTR_SET(vap, va_uid, mp->mnt_fsowner);
} else {
/* default owner is current user */
VATTR_SET(vap, va_uid,
kauth_cred_getuid(vfs_context_ucred(ctx)));
}
if ((mp->mnt_flag & MNT_IGNORE_OWNERSHIP) &&
(mp->mnt_fsgroup != KAUTH_GID_NONE)) {
VATTR_SET(vap, va_gid, mp->mnt_fsgroup);
} else {
/*
* default group comes from parent object,
* fallback to current user
*/
if (VATTR_IS_SUPPORTED(dvap, va_gid)) {
VATTR_SET(vap, va_gid, dvap->va_gid);
} else {
VATTR_SET(vap, va_gid,
kauth_cred_getgid(vfs_context_ucred(ctx)));
}
}
}
/* Inherit SF_RESTRICTED bit from destination directory only */
if (VATTR_IS_ACTIVE(vap, va_flags)) {
VATTR_SET(vap, va_flags,
((vap->va_flags & ~(UF_DATAVAULT | SF_RESTRICTED)))); /* Turn off from source */
if (VATTR_IS_ACTIVE(dvap, va_flags)) {
VATTR_SET(vap, va_flags,
vap->va_flags | (dvap->va_flags & (UF_DATAVAULT | SF_RESTRICTED)));
}
} else if (VATTR_IS_ACTIVE(dvap, va_flags)) {
VATTR_SET(vap, va_flags, (dvap->va_flags & (UF_DATAVAULT | SF_RESTRICTED)));
}
return 0;
}
/*
* Authorize an operation on a vnode.
*
* This is KPI, but here because it needs vnode_scope.
*
* Returns: 0 Success
* kauth_authorize_action:EPERM ...
* xlate => EACCES Permission denied
* kauth_authorize_action:0 Success
* kauth_authorize_action: Depends on callback return; this is
* usually only vnode_authorize_callback(),
* but may include other listerners, if any
* exist.
* EROFS
* EACCES
* EPERM
* ???
*/
int
vnode_authorize(vnode_t vp, vnode_t dvp, kauth_action_t action, vfs_context_t ctx)
{
int error, result;
/*
* We can't authorize against a dead vnode; allow all operations through so that
* the correct error can be returned.
*/
if (vp->v_type == VBAD) {
return 0;
}
error = 0;
result = kauth_authorize_action(vnode_scope, vfs_context_ucred(ctx), action,
(uintptr_t)ctx, (uintptr_t)vp, (uintptr_t)dvp, (uintptr_t)&error);
if (result == EPERM) { /* traditional behaviour */
result = EACCES;
}
/* did the lower layers give a better error return? */
if ((result != 0) && (error != 0)) {
return error;
}
return result;
}
/*
* Test for vnode immutability.
*
* The 'append' flag is set when the authorization request is constrained
* to operations which only request the right to append to a file.
*
* The 'ignore' flag is set when an operation modifying the immutability flags
* is being authorized. We check the system securelevel to determine which
* immutability flags we can ignore.
*/
static int
vnode_immutable(struct vnode_attr *vap, int append, int ignore)
{
int mask;
/* start with all bits precluding the operation */
mask = IMMUTABLE | APPEND;
/* if appending only, remove the append-only bits */
if (append) {
mask &= ~APPEND;
}
/* ignore only set when authorizing flags changes */
if (ignore) {
if (securelevel <= 0) {
/* in insecure state, flags do not inhibit changes */
mask = 0;
} else {
/* in secure state, user flags don't inhibit */
mask &= ~(UF_IMMUTABLE | UF_APPEND);
}
}
KAUTH_DEBUG("IMMUTABLE - file flags 0x%x mask 0x%x append = %d ignore = %d", vap->va_flags, mask, append, ignore);
if ((vap->va_flags & mask) != 0) {
return EPERM;
}
return 0;
}
static int
vauth_node_owner(struct vnode_attr *vap, kauth_cred_t cred)
{
int result;
/* default assumption is not-owner */
result = 0;
/*
* If the filesystem has given us a UID, we treat this as authoritative.
*/
if (vap && VATTR_IS_SUPPORTED(vap, va_uid)) {
result = (vap->va_uid == kauth_cred_getuid(cred)) ? 1 : 0;
}
/* we could test the owner UUID here if we had a policy for it */
return result;
}
/*
* vauth_node_group
*
* Description: Ask if a cred is a member of the group owning the vnode object
*
* Parameters: vap vnode attribute
* vap->va_gid group owner of vnode object
* cred credential to check
* ismember pointer to where to put the answer
* idontknow Return this if we can't get an answer
*
* Returns: 0 Success
* idontknow Can't get information
* kauth_cred_ismember_gid:? Error from kauth subsystem
* kauth_cred_ismember_gid:? Error from kauth subsystem
*/
static int
vauth_node_group(struct vnode_attr *vap, kauth_cred_t cred, int *ismember, int idontknow)
{
int error;
int result;
error = 0;
result = 0;
/*
* The caller is expected to have asked the filesystem for a group
* at some point prior to calling this function. The answer may
* have been that there is no group ownership supported for the
* vnode object, in which case we return
*/
if (vap && VATTR_IS_SUPPORTED(vap, va_gid)) {
error = kauth_cred_ismember_gid(cred, vap->va_gid, &result);
/*
* Credentials which are opted into external group membership
* resolution which are not known to the external resolver
* will result in an ENOENT error. We translate this into
* the appropriate 'idontknow' response for our caller.
*
* XXX We do not make a distinction here between an ENOENT
* XXX arising from a response from the external resolver,
* XXX and an ENOENT which is internally generated. This is
* XXX a deficiency of the published kauth_cred_ismember_gid()
* XXX KPI which can not be overcome without new KPI. For
* XXX all currently known cases, however, this wil result
* XXX in correct behaviour.
*/
if (error == ENOENT) {
error = idontknow;
}
}
/*
* XXX We could test the group UUID here if we had a policy for it,
* XXX but this is problematic from the perspective of synchronizing
* XXX group UUID and POSIX GID ownership of a file and keeping the
* XXX values coherent over time. The problem is that the local
* XXX system will vend transient group UUIDs for unknown POSIX GID
* XXX values, and these are not persistent, whereas storage of values
* XXX is persistent. One potential solution to this is a local
* XXX (persistent) replica of remote directory entries and vended
* XXX local ids in a local directory server (think in terms of a
* XXX caching DNS server).
*/
if (!error) {
*ismember = result;
}
return error;
}
static int
vauth_file_owner(vauth_ctx vcp)
{
int result;
if (vcp->flags_valid & _VAC_IS_OWNER) {
result = (vcp->flags & _VAC_IS_OWNER) ? 1 : 0;
} else {
result = vauth_node_owner(vcp->vap, vcp->ctx->vc_ucred);
/* cache our result */
vcp->flags_valid |= _VAC_IS_OWNER;
if (result) {
vcp->flags |= _VAC_IS_OWNER;
} else {
vcp->flags &= ~_VAC_IS_OWNER;
}
}
return result;
}
/*
* vauth_file_ingroup
*
* Description: Ask if a user is a member of the group owning the directory
*
* Parameters: vcp The vnode authorization context that
* contains the user and directory info
* vcp->flags_valid Valid flags
* vcp->flags Flags values
* vcp->vap File vnode attributes
* vcp->ctx VFS Context (for user)
* ismember pointer to where to put the answer
* idontknow Return this if we can't get an answer
*
* Returns: 0 Success
* vauth_node_group:? Error from vauth_node_group()
*
* Implicit returns: *ismember 0 The user is not a group member
* 1 The user is a group member
*/
static int
vauth_file_ingroup(vauth_ctx vcp, int *ismember, int idontknow)
{
int error;
/* Check for a cached answer first, to avoid the check if possible */
if (vcp->flags_valid & _VAC_IN_GROUP) {
*ismember = (vcp->flags & _VAC_IN_GROUP) ? 1 : 0;
error = 0;
} else {
/* Otherwise, go look for it */
error = vauth_node_group(vcp->vap, vcp->ctx->vc_ucred, ismember, idontknow);
if (!error) {
/* cache our result */
vcp->flags_valid |= _VAC_IN_GROUP;
if (*ismember) {
vcp->flags |= _VAC_IN_GROUP;
} else {
vcp->flags &= ~_VAC_IN_GROUP;
}
}
}
return error;
}
static int
vauth_dir_owner(vauth_ctx vcp)
{
int result;
if (vcp->flags_valid & _VAC_IS_DIR_OWNER) {
result = (vcp->flags & _VAC_IS_DIR_OWNER) ? 1 : 0;
} else {
result = vauth_node_owner(vcp->dvap, vcp->ctx->vc_ucred);
/* cache our result */
vcp->flags_valid |= _VAC_IS_DIR_OWNER;
if (result) {
vcp->flags |= _VAC_IS_DIR_OWNER;
} else {
vcp->flags &= ~_VAC_IS_DIR_OWNER;
}
}
return result;
}
/*
* vauth_dir_ingroup
*
* Description: Ask if a user is a member of the group owning the directory
*
* Parameters: vcp The vnode authorization context that
* contains the user and directory info
* vcp->flags_valid Valid flags
* vcp->flags Flags values
* vcp->dvap Dir vnode attributes
* vcp->ctx VFS Context (for user)
* ismember pointer to where to put the answer
* idontknow Return this if we can't get an answer
*
* Returns: 0 Success
* vauth_node_group:? Error from vauth_node_group()
*
* Implicit returns: *ismember 0 The user is not a group member
* 1 The user is a group member
*/
static int
vauth_dir_ingroup(vauth_ctx vcp, int *ismember, int idontknow)
{
int error;
/* Check for a cached answer first, to avoid the check if possible */
if (vcp->flags_valid & _VAC_IN_DIR_GROUP) {
*ismember = (vcp->flags & _VAC_IN_DIR_GROUP) ? 1 : 0;
error = 0;
} else {
/* Otherwise, go look for it */
error = vauth_node_group(vcp->dvap, vcp->ctx->vc_ucred, ismember, idontknow);
if (!error) {
/* cache our result */
vcp->flags_valid |= _VAC_IN_DIR_GROUP;
if (*ismember) {
vcp->flags |= _VAC_IN_DIR_GROUP;
} else {
vcp->flags &= ~_VAC_IN_DIR_GROUP;
}
}
}
return error;
}
/*
* Test the posix permissions in (vap) to determine whether (credential)
* may perform (action)
*/
static int
vnode_authorize_posix(vauth_ctx vcp, int action, int on_dir)
{
struct vnode_attr *vap;
int needed, error, owner_ok, group_ok, world_ok, ismember;
#ifdef KAUTH_DEBUG_ENABLE
const char *where = "uninitialized";
# define _SETWHERE(c) where = c;
#else
# define _SETWHERE(c)
#endif
/* checking file or directory? */
if (on_dir) {
vap = vcp->dvap;
} else {
vap = vcp->vap;
}
error = 0;
/*
* We want to do as little work here as possible. So first we check
* which sets of permissions grant us the access we need, and avoid checking
* whether specific permissions grant access when more generic ones would.
*/
/* owner permissions */
needed = 0;
if (action & VREAD) {
needed |= S_IRUSR;
}
if (action & VWRITE) {
needed |= S_IWUSR;
}
if (action & VEXEC) {
needed |= S_IXUSR;
}
owner_ok = (needed & vap->va_mode) == needed;
/*
* Processes with the appropriate entitlement can marked themselves as
* ignoring file/directory permissions if they own it.
*/
if (!owner_ok && proc_ignores_node_permissions(vfs_context_proc(vcp->ctx))) {
owner_ok = 1;
}
/* group permissions */
needed = 0;
if (action & VREAD) {
needed |= S_IRGRP;
}
if (action & VWRITE) {
needed |= S_IWGRP;
}
if (action & VEXEC) {
needed |= S_IXGRP;
}
group_ok = (needed & vap->va_mode) == needed;
/* world permissions */
needed = 0;
if (action & VREAD) {
needed |= S_IROTH;
}
if (action & VWRITE) {
needed |= S_IWOTH;
}
if (action & VEXEC) {
needed |= S_IXOTH;
}
world_ok = (needed & vap->va_mode) == needed;
/* If granted/denied by all three, we're done */
if (owner_ok && group_ok && world_ok) {
_SETWHERE("all");
goto out;
}
if (!owner_ok && !group_ok && !world_ok) {
_SETWHERE("all");
error = EACCES;
goto out;
}
/* Check ownership (relatively cheap) */
if ((on_dir && vauth_dir_owner(vcp)) ||
(!on_dir && vauth_file_owner(vcp))) {
_SETWHERE("user");
if (!owner_ok) {
error = EACCES;
}
goto out;
}
/* Not owner; if group and world both grant it we're done */
if (group_ok && world_ok) {
_SETWHERE("group/world");
goto out;
}
if (!group_ok && !world_ok) {
_SETWHERE("group/world");
error = EACCES;
goto out;
}
/* Check group membership (most expensive) */
ismember = 0; /* Default to allow, if the target has no group owner */
/*
* In the case we can't get an answer about the user from the call to
* vauth_dir_ingroup() or vauth_file_ingroup(), we want to fail on
* the side of caution, rather than simply granting access, or we will
* fail to correctly implement exclusion groups, so we set the third
* parameter on the basis of the state of 'group_ok'.
*/
if (on_dir) {
error = vauth_dir_ingroup(vcp, &ismember, (!group_ok ? EACCES : 0));
} else {
error = vauth_file_ingroup(vcp, &ismember, (!group_ok ? EACCES : 0));
}
if (error) {
if (!group_ok) {
ismember = 1;
}
error = 0;
}
if (ismember) {
_SETWHERE("group");
if (!group_ok) {
error = EACCES;
}
goto out;
}
/* Not owner, not in group, use world result */
_SETWHERE("world");
if (!world_ok) {
error = EACCES;
}
/* FALLTHROUGH */
out:
KAUTH_DEBUG("%p %s - posix %s permissions : need %s%s%s %x have %s%s%s%s%s%s%s%s%s UID = %d file = %d,%d",
vcp->vp, (error == 0) ? "ALLOWED" : "DENIED", where,
(action & VREAD) ? "r" : "-",
(action & VWRITE) ? "w" : "-",
(action & VEXEC) ? "x" : "-",
needed,
(vap->va_mode & S_IRUSR) ? "r" : "-",
(vap->va_mode & S_IWUSR) ? "w" : "-",
(vap->va_mode & S_IXUSR) ? "x" : "-",
(vap->va_mode & S_IRGRP) ? "r" : "-",
(vap->va_mode & S_IWGRP) ? "w" : "-",
(vap->va_mode & S_IXGRP) ? "x" : "-",
(vap->va_mode & S_IROTH) ? "r" : "-",
(vap->va_mode & S_IWOTH) ? "w" : "-",
(vap->va_mode & S_IXOTH) ? "x" : "-",
kauth_cred_getuid(vcp->ctx->vc_ucred),
on_dir ? vcp->dvap->va_uid : vcp->vap->va_uid,
on_dir ? vcp->dvap->va_gid : vcp->vap->va_gid);
return error;
}
/*
* Authorize the deletion of the node vp from the directory dvp.
*
* We assume that:
* - Neither the node nor the directory are immutable.
* - The user is not the superuser.
*
* The precedence of factors for authorizing or denying delete for a credential
*
* 1) Explicit ACE on the node. (allow or deny DELETE)
* 2) Explicit ACE on the directory (allow or deny DELETE_CHILD).
*
* If there are conflicting ACEs on the node and the directory, the node
* ACE wins.
*
* 3) Sticky bit on the directory.
* Deletion is not permitted if the directory is sticky and the caller is
* not owner of the node or directory. The sticky bit rules are like a deny
* delete ACE except lower in priority than ACL's either allowing or denying
* delete.
*
* 4) POSIX permisions on the directory.
*
* As an optimization, we cache whether or not delete child is permitted
* on directories. This enables us to skip directory ACL and POSIX checks
* as we already have the result from those checks. However, we always check the
* node ACL and, if the directory has the sticky bit set, we always check its
* ACL (even for a directory with an authorized delete child). Furthermore,
* caching the delete child authorization is independent of the sticky bit
* being set as it is only applicable in determining whether the node can be
* deleted or not.
*/
static int
vnode_authorize_delete(vauth_ctx vcp, boolean_t cached_delete_child)
{
struct vnode_attr *vap = vcp->vap;
struct vnode_attr *dvap = vcp->dvap;
kauth_cred_t cred = vcp->ctx->vc_ucred;
struct kauth_acl_eval eval;
int error, ismember;
/* Check the ACL on the node first */
if (VATTR_IS_NOT(vap, va_acl, NULL)) {
eval.ae_requested = KAUTH_VNODE_DELETE;
eval.ae_acl = &vap->va_acl->acl_ace[0];
eval.ae_count = vap->va_acl->acl_entrycount;
eval.ae_options = 0;
if (vauth_file_owner(vcp)) {
eval.ae_options |= KAUTH_AEVAL_IS_OWNER;
}
/*
* We use ENOENT as a marker to indicate we could not get
* information in order to delay evaluation until after we
* have the ACL evaluation answer. Previously, we would
* always deny the operation at this point.
*/
if ((error = vauth_file_ingroup(vcp, &ismember, ENOENT)) != 0 && error != ENOENT) {
return error;
}
if (error == ENOENT) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP_UNKNOWN;
} else if (ismember) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP;
}
eval.ae_exp_gall = KAUTH_VNODE_GENERIC_ALL_BITS;
eval.ae_exp_gread = KAUTH_VNODE_GENERIC_READ_BITS;
eval.ae_exp_gwrite = KAUTH_VNODE_GENERIC_WRITE_BITS;
eval.ae_exp_gexec = KAUTH_VNODE_GENERIC_EXECUTE_BITS;
if ((error = kauth_acl_evaluate(cred, &eval)) != 0) {
KAUTH_DEBUG("%p ERROR during ACL processing - %d", vcp->vp, error);
return error;
}
switch (eval.ae_result) {
case KAUTH_RESULT_DENY:
if (vauth_file_owner(vcp) && proc_ignores_node_permissions(vfs_context_proc(vcp->ctx))) {
KAUTH_DEBUG("%p Override DENY due to entitlement", vcp->vp);
return 0;
}
KAUTH_DEBUG("%p DENIED - denied by ACL", vcp->vp);
return EACCES;
case KAUTH_RESULT_ALLOW:
KAUTH_DEBUG("%p ALLOWED - granted by ACL", vcp->vp);
return 0;
case KAUTH_RESULT_DEFER:
default:
/* Defer to directory */
KAUTH_DEBUG("%p DEFERRED - by file ACL", vcp->vp);
break;
}
}
/*
* Without a sticky bit, a previously authorized delete child is
* sufficient to authorize this delete.
*
* If the sticky bit is set, a directory ACL which allows delete child
* overrides a (potential) sticky bit deny. The authorized delete child
* cannot tell us if it was authorized because of an explicit delete
* child allow ACE or because of POSIX permisions so we have to check
* the directory ACL everytime if the directory has a sticky bit.
*/
if (!(dvap->va_mode & S_ISTXT) && cached_delete_child) {
KAUTH_DEBUG("%p ALLOWED - granted by directory ACL or POSIX permissions and no sticky bit on directory", vcp->vp);
return 0;
}
/* check the ACL on the directory */
if (VATTR_IS_NOT(dvap, va_acl, NULL)) {
eval.ae_requested = KAUTH_VNODE_DELETE_CHILD;
eval.ae_acl = &dvap->va_acl->acl_ace[0];
eval.ae_count = dvap->va_acl->acl_entrycount;
eval.ae_options = 0;
if (vauth_dir_owner(vcp)) {
eval.ae_options |= KAUTH_AEVAL_IS_OWNER;
}
/*
* We use ENOENT as a marker to indicate we could not get
* information in order to delay evaluation until after we
* have the ACL evaluation answer. Previously, we would
* always deny the operation at this point.
*/
if ((error = vauth_dir_ingroup(vcp, &ismember, ENOENT)) != 0 && error != ENOENT) {
return error;
}
if (error == ENOENT) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP_UNKNOWN;
} else if (ismember) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP;
}
eval.ae_exp_gall = KAUTH_VNODE_GENERIC_ALL_BITS;
eval.ae_exp_gread = KAUTH_VNODE_GENERIC_READ_BITS;
eval.ae_exp_gwrite = KAUTH_VNODE_GENERIC_WRITE_BITS;
eval.ae_exp_gexec = KAUTH_VNODE_GENERIC_EXECUTE_BITS;
/*
* If there is no entry, we are going to defer to other
* authorization mechanisms.
*/
error = kauth_acl_evaluate(cred, &eval);
if (error != 0) {
KAUTH_DEBUG("%p ERROR during ACL processing - %d", vcp->vp, error);
return error;
}
switch (eval.ae_result) {
case KAUTH_RESULT_DENY:
if (vauth_dir_owner(vcp) && proc_ignores_node_permissions(vfs_context_proc(vcp->ctx))) {
KAUTH_DEBUG("%p Override DENY due to entitlement", vcp->vp);
return 0;
}
KAUTH_DEBUG("%p DENIED - denied by directory ACL", vcp->vp);
return EACCES;
case KAUTH_RESULT_ALLOW:
KAUTH_DEBUG("%p ALLOWED - granted by directory ACL", vcp->vp);
if (!cached_delete_child && vcp->dvp) {
vnode_cache_authorized_action(vcp->dvp,
vcp->ctx, KAUTH_VNODE_DELETE_CHILD);
}
return 0;
case KAUTH_RESULT_DEFER:
default:
/* Deferred by directory ACL */
KAUTH_DEBUG("%p DEFERRED - directory ACL", vcp->vp);
break;
}
}
/*
* From this point, we can't explicitly allow and if we reach the end
* of the function without a denial, then the delete is authorized.
*/
if (!cached_delete_child) {
if (vnode_authorize_posix(vcp, VWRITE, 1 /* on_dir */) != 0) {
KAUTH_DEBUG("%p DENIED - denied by posix permisssions", vcp->vp);
return EACCES;
}
/*
* Cache the authorized action on the vnode if allowed by the
* directory ACL or POSIX permissions. It is correct to cache
* this action even if sticky bit would deny deleting the node.
*/
if (vcp->dvp) {
vnode_cache_authorized_action(vcp->dvp, vcp->ctx,
KAUTH_VNODE_DELETE_CHILD);
}
}
/* enforce sticky bit behaviour */
if ((dvap->va_mode & S_ISTXT) && !vauth_file_owner(vcp) && !vauth_dir_owner(vcp)) {
KAUTH_DEBUG("%p DENIED - sticky bit rules (user %d file %d dir %d)",
vcp->vp, cred->cr_posix.cr_uid, vap->va_uid, dvap->va_uid);
return EACCES;
}
/* not denied, must be OK */
return 0;
}
/*
* Authorize an operation based on the node's attributes.
*/
static int
vnode_authorize_simple(vauth_ctx vcp, kauth_ace_rights_t acl_rights, kauth_ace_rights_t preauth_rights, boolean_t *found_deny)
{
struct vnode_attr *vap = vcp->vap;
kauth_cred_t cred = vcp->ctx->vc_ucred;
struct kauth_acl_eval eval;
int error, ismember;
mode_t posix_action;
/*
* If we are the file owner, we automatically have some rights.
*
* Do we need to expand this to support group ownership?
*/
if (vauth_file_owner(vcp)) {
acl_rights &= ~(KAUTH_VNODE_WRITE_SECURITY);
}
/*
* If we are checking both TAKE_OWNERSHIP and WRITE_SECURITY, we can
* mask the latter. If TAKE_OWNERSHIP is requested the caller is about to
* change ownership to themselves, and WRITE_SECURITY is implicitly
* granted to the owner. We need to do this because at this point
* WRITE_SECURITY may not be granted as the caller is not currently
* the owner.
*/
if ((acl_rights & KAUTH_VNODE_TAKE_OWNERSHIP) &&
(acl_rights & KAUTH_VNODE_WRITE_SECURITY)) {
acl_rights &= ~KAUTH_VNODE_WRITE_SECURITY;
}
if (acl_rights == 0) {
KAUTH_DEBUG("%p ALLOWED - implicit or no rights required", vcp->vp);
return 0;
}
/* if we have an ACL, evaluate it */
if (VATTR_IS_NOT(vap, va_acl, NULL)) {
eval.ae_requested = acl_rights;
eval.ae_acl = &vap->va_acl->acl_ace[0];
eval.ae_count = vap->va_acl->acl_entrycount;
eval.ae_options = 0;
if (vauth_file_owner(vcp)) {
eval.ae_options |= KAUTH_AEVAL_IS_OWNER;
}
/*
* We use ENOENT as a marker to indicate we could not get
* information in order to delay evaluation until after we
* have the ACL evaluation answer. Previously, we would
* always deny the operation at this point.
*/
if ((error = vauth_file_ingroup(vcp, &ismember, ENOENT)) != 0 && error != ENOENT) {
return error;
}
if (error == ENOENT) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP_UNKNOWN;
} else if (ismember) {
eval.ae_options |= KAUTH_AEVAL_IN_GROUP;
}
eval.ae_exp_gall = KAUTH_VNODE_GENERIC_ALL_BITS;
eval.ae_exp_gread = KAUTH_VNODE_GENERIC_READ_BITS;
eval.ae_exp_gwrite = KAUTH_VNODE_GENERIC_WRITE_BITS;
eval.ae_exp_gexec = KAUTH_VNODE_GENERIC_EXECUTE_BITS;
if ((error = kauth_acl_evaluate(cred, &eval)) != 0) {
KAUTH_DEBUG("%p ERROR during ACL processing - %d", vcp->vp, error);
return error;
}
switch (eval.ae_result) {
case KAUTH_RESULT_DENY:
if (vauth_file_owner(vcp) && proc_ignores_node_permissions(vfs_context_proc(vcp->ctx))) {
KAUTH_DEBUG("%p Override DENY due to entitlement", vcp->vp);
return 0;
}
KAUTH_DEBUG("%p DENIED - by ACL", vcp->vp);
return EACCES; /* deny, deny, counter-allege */
case KAUTH_RESULT_ALLOW:
KAUTH_DEBUG("%p ALLOWED - all rights granted by ACL", vcp->vp);
return 0;
case KAUTH_RESULT_DEFER:
default:
/* Effectively the same as !delete_child_denied */
KAUTH_DEBUG("%p DEFERRED - directory ACL", vcp->vp);
break;
}
*found_deny = eval.ae_found_deny;
/* fall through and evaluate residual rights */
} else {
/* no ACL, everything is residual */
eval.ae_residual = acl_rights;
}
/*
* Grant residual rights that have been pre-authorized.
*/
eval.ae_residual &= ~preauth_rights;
/*
* We grant WRITE_ATTRIBUTES to the owner if it hasn't been denied.
*/
if (vauth_file_owner(vcp)) {
eval.ae_residual &= ~KAUTH_VNODE_WRITE_ATTRIBUTES;
}
if (eval.ae_residual == 0) {
KAUTH_DEBUG("%p ALLOWED - rights already authorized", vcp->vp);
return 0;
}
/*
* Bail if we have residual rights that can't be granted by posix permissions,
* or aren't presumed granted at this point.
*
* XXX these can be collapsed for performance
*/
if (eval.ae_residual & KAUTH_VNODE_CHANGE_OWNER) {
KAUTH_DEBUG("%p DENIED - CHANGE_OWNER not permitted", vcp->vp);
return EACCES;
}
if (eval.ae_residual & KAUTH_VNODE_WRITE_SECURITY) {
KAUTH_DEBUG("%p DENIED - WRITE_SECURITY not permitted", vcp->vp);
return EACCES;
}
#if DIAGNOSTIC
if (eval.ae_residual & KAUTH_VNODE_DELETE) {
panic("vnode_authorize: can't be checking delete permission here");
}
#endif
/*
* Compute the fallback posix permissions that will satisfy the remaining
* rights.
*/
posix_action = 0;
if (eval.ae_residual & (KAUTH_VNODE_READ_DATA |
KAUTH_VNODE_LIST_DIRECTORY |
KAUTH_VNODE_READ_EXTATTRIBUTES)) {
posix_action |= VREAD;
}
if (eval.ae_residual & (KAUTH_VNODE_WRITE_DATA |
KAUTH_VNODE_ADD_FILE |
KAUTH_VNODE_ADD_SUBDIRECTORY |
KAUTH_VNODE_DELETE_CHILD |
KAUTH_VNODE_WRITE_ATTRIBUTES |
KAUTH_VNODE_WRITE_EXTATTRIBUTES)) {
posix_action |= VWRITE;
}
if (eval.ae_residual & (KAUTH_VNODE_EXECUTE |
KAUTH_VNODE_SEARCH)) {
posix_action |= VEXEC;
}
if (posix_action != 0) {
return vnode_authorize_posix(vcp, posix_action, 0 /* !on_dir */);
} else {
KAUTH_DEBUG("%p ALLOWED - residual rights %s%s%s%s%s%s%s%s%s%s%s%s%s%s granted due to no posix mapping",
vcp->vp,
(eval.ae_residual & KAUTH_VNODE_READ_DATA)
? vnode_isdir(vcp->vp) ? " LIST_DIRECTORY" : " READ_DATA" : "",
(eval.ae_residual & KAUTH_VNODE_WRITE_DATA)
? vnode_isdir(vcp->vp) ? " ADD_FILE" : " WRITE_DATA" : "",
(eval.ae_residual & KAUTH_VNODE_EXECUTE)
? vnode_isdir(vcp->vp) ? " SEARCH" : " EXECUTE" : "",
(eval.ae_residual & KAUTH_VNODE_DELETE)
? " DELETE" : "",
(eval.ae_residual & KAUTH_VNODE_APPEND_DATA)
? vnode_isdir(vcp->vp) ? " ADD_SUBDIRECTORY" : " APPEND_DATA" : "",
(eval.ae_residual & KAUTH_VNODE_DELETE_CHILD)
? " DELETE_CHILD" : "",
(eval.ae_residual & KAUTH_VNODE_READ_ATTRIBUTES)
? " READ_ATTRIBUTES" : "",
(eval.ae_residual & KAUTH_VNODE_WRITE_ATTRIBUTES)
? " WRITE_ATTRIBUTES" : "",
(eval.ae_residual & KAUTH_VNODE_READ_EXTATTRIBUTES)
? " READ_EXTATTRIBUTES" : "",
(eval.ae_residual & KAUTH_VNODE_WRITE_EXTATTRIBUTES)
? " WRITE_EXTATTRIBUTES" : "",
(eval.ae_residual & KAUTH_VNODE_READ_SECURITY)
? " READ_SECURITY" : "",
(eval.ae_residual & KAUTH_VNODE_WRITE_SECURITY)
? " WRITE_SECURITY" : "",
(eval.ae_residual & KAUTH_VNODE_CHECKIMMUTABLE)
? " CHECKIMMUTABLE" : "",
(eval.ae_residual & KAUTH_VNODE_CHANGE_OWNER)
? " CHANGE_OWNER" : "");
}
/*
* Lack of required Posix permissions implies no reason to deny access.
*/
return 0;
}
/*
* Check for file immutability.
*/
static int
vnode_authorize_checkimmutable(mount_t mp, vauth_ctx vcp,
struct vnode_attr *vap, int rights, int ignore)
{
int error;
int append;
/*
* Perform immutability checks for operations that change data.
*
* Sockets, fifos and devices require special handling.
*/
switch (vap->va_type) {
case VSOCK:
case VFIFO:
case VBLK:
case VCHR:
/*
* Writing to these nodes does not change the filesystem data,
* so forget that it's being tried.
*/
rights &= ~KAUTH_VNODE_WRITE_DATA;
break;
default:
break;
}
error = 0;
if (rights & KAUTH_VNODE_WRITE_RIGHTS) {
/* check per-filesystem options if possible */
if (mp != NULL) {
/* check for no-EA filesystems */
if ((rights & KAUTH_VNODE_WRITE_EXTATTRIBUTES) &&
(vfs_flags(mp) & MNT_NOUSERXATTR)) {
KAUTH_DEBUG("%p DENIED - filesystem disallowed extended attributes", vap);
error = EACCES; /* User attributes disabled */
goto out;
}
}
/*
* check for file immutability. first, check if the requested rights are
* allowable for a UF_APPEND file.
*/
append = 0;
if (vap->va_type == VDIR) {
if ((rights & (KAUTH_VNODE_ADD_FILE | KAUTH_VNODE_ADD_SUBDIRECTORY | KAUTH_VNODE_WRITE_EXTATTRIBUTES | ~KAUTH_VNODE_WRITE_RIGHTS)) == rights) {
append = 1;
}
} else {
if ((rights & (KAUTH_VNODE_APPEND_DATA | KAUTH_VNODE_WRITE_EXTATTRIBUTES | ~KAUTH_VNODE_WRITE_RIGHTS)) == rights) {
append = 1;
}
}
if ((error = vnode_immutable(vap, append, ignore)) != 0) {
if (error && !ignore) {
/*
* In case of a rename, we want to check ownership for dvp as well.
*/
int owner = 0;
if (rights & KAUTH_VNODE_DELETE_CHILD && vcp->dvp != NULL) {
owner = vauth_file_owner(vcp) && vauth_dir_owner(vcp);
} else {
owner = vauth_file_owner(vcp);
}
if (owner && proc_ignores_node_permissions(vfs_context_proc(vcp->ctx))) {
error = vnode_immutable(vap, append, 1);
}
}
}
if (error) {
KAUTH_DEBUG("%p DENIED - file is immutable", vap);
goto out;
}
}
out:
return error;
}
/*
* Handle authorization actions for filesystems that advertise that the
* server will be enforcing.
*
* Returns: 0 Authorization should be handled locally
* 1 Authorization was handled by the FS
*
* Note: Imputed returns will only occur if the authorization request
* was handled by the FS.
*
* Imputed: *resultp, modified Return code from FS when the request is
* handled by the FS.
* VNOP_ACCESS:???
* VNOP_OPEN:???
*/
static int
vnode_authorize_opaque(vnode_t vp, int *resultp, kauth_action_t action, vfs_context_t ctx)
{
int error;
/*
* If the vp is a device node, socket or FIFO it actually represents a local
* endpoint, so we need to handle it locally.
*/
switch (vp->v_type) {
case VBLK:
case VCHR:
case VSOCK:
case VFIFO:
return 0;
default:
break;
}
/*
* In the advisory request case, if the filesystem doesn't think it's reliable
* we will attempt to formulate a result ourselves based on VNOP_GETATTR data.
*/
if ((action & KAUTH_VNODE_ACCESS) && !vfs_authopaqueaccess(vp->v_mount)) {
return 0;
}
/*
* Let the filesystem have a say in the matter. It's OK for it to not implemnent
* VNOP_ACCESS, as most will authorise inline with the actual request.
*/
if ((error = VNOP_ACCESS(vp, action, ctx)) != ENOTSUP) {
*resultp = error;
KAUTH_DEBUG("%p DENIED - opaque filesystem VNOP_ACCESS denied access", vp);
return 1;
}
/*
* Typically opaque filesystems do authorisation in-line, but exec is a special case. In
* order to be reasonably sure that exec will be permitted, we try a bit harder here.
*/
if ((action & KAUTH_VNODE_EXECUTE) && (vp->v_type == VREG)) {
/* try a VNOP_OPEN for readonly access */
if ((error = VNOP_OPEN(vp, FREAD, ctx)) != 0) {
*resultp = error;
KAUTH_DEBUG("%p DENIED - EXECUTE denied because file could not be opened readonly", vp);
return 1;
}
VNOP_CLOSE(vp, FREAD, ctx);
}
/*
* We don't have any reason to believe that the request has to be denied at this point,
* so go ahead and allow it.
*/
*resultp = 0;
KAUTH_DEBUG("%p ALLOWED - bypassing access check for non-local filesystem", vp);
return 1;
}
/*
* Returns: KAUTH_RESULT_ALLOW
* KAUTH_RESULT_DENY
*
* Imputed: *arg3, modified Error code in the deny case
* EROFS Read-only file system
* EACCES Permission denied
* EPERM Operation not permitted [no execute]
* vnode_getattr:ENOMEM Not enough space [only if has filesec]
* vnode_getattr:???
* vnode_authorize_opaque:*arg2 ???
* vnode_authorize_checkimmutable:???
* vnode_authorize_delete:???
* vnode_authorize_simple:???
*/
static int
vnode_authorize_callback(__unused kauth_cred_t cred, __unused void *idata,
kauth_action_t action, uintptr_t arg0, uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3)
{
vfs_context_t ctx;
vnode_t cvp = NULLVP;
vnode_t vp, dvp;
int result = KAUTH_RESULT_DENY;
int parent_iocount = 0;
int parent_action = 0; /* In case we need to use namedstream's data fork for cached rights*/
ctx = (vfs_context_t)arg0;
vp = (vnode_t)arg1;
dvp = (vnode_t)arg2;
/*
* if there are 2 vnodes passed in, we don't know at
* this point which rights to look at based on the
* combined action being passed in... defer until later...
* otherwise check the kauth 'rights' cache hung
* off of the vnode we're interested in... if we've already
* been granted the right we're currently interested in,
* we can just return success... otherwise we'll go through
* the process of authorizing the requested right(s)... if that
* succeeds, we'll add the right(s) to the cache.
* VNOP_SETATTR and VNOP_SETXATTR will invalidate this cache
*/
if (dvp && vp) {
goto defer;
}
if (dvp) {
cvp = dvp;
} else {
/*
* For named streams on local-authorization volumes, rights are cached on the parent;
* authorization is determined by looking at the parent's properties anyway, so storing
* on the parent means that we don't recompute for the named stream and that if
* we need to flush rights (e.g. on VNOP_SETATTR()) we don't need to track down the
* stream to flush its cache separately. If we miss in the cache, then we authorize
* as if there were no cached rights (passing the named stream vnode and desired rights to
* vnode_authorize_callback_int()).
*
* On an opaquely authorized volume, we don't know the relationship between the
* data fork's properties and the rights granted on a stream. Thus, named stream vnodes
* on such a volume are authorized directly (rather than using the parent) and have their
* own caches. When a named stream vnode is created, we mark the parent as having a named
* stream. On a VNOP_SETATTR() for the parent that may invalidate cached authorization, we
* find the stream and flush its cache.
*/
if (vnode_isnamedstream(vp) && (!vfs_authopaque(vp->v_mount))) {
cvp = vnode_getparent(vp);
if (cvp != NULLVP) {
parent_iocount = 1;
} else {
cvp = NULL;
goto defer; /* If we can't use the parent, take the slow path */
}
/* Have to translate some actions */
parent_action = action;
if (parent_action & KAUTH_VNODE_READ_DATA) {
parent_action &= ~KAUTH_VNODE_READ_DATA;
parent_action |= KAUTH_VNODE_READ_EXTATTRIBUTES;
}
if (parent_action & KAUTH_VNODE_WRITE_DATA) {
parent_action &= ~KAUTH_VNODE_WRITE_DATA;
parent_action |= KAUTH_VNODE_WRITE_EXTATTRIBUTES;
}
} else {
cvp = vp;
}
}
if (vnode_cache_is_authorized(cvp, ctx, parent_iocount ? parent_action : action) == TRUE) {
result = KAUTH_RESULT_ALLOW;
goto out;
}
defer:
result = vnode_authorize_callback_int(action, ctx, vp, dvp, (int *)arg3);
if (result == KAUTH_RESULT_ALLOW && cvp != NULLVP) {
KAUTH_DEBUG("%p - caching action = %x", cvp, action);
vnode_cache_authorized_action(cvp, ctx, action);
}
out:
if (parent_iocount) {
vnode_put(cvp);
}
return result;
}
static int
vnode_attr_authorize_internal(vauth_ctx vcp, mount_t mp,
kauth_ace_rights_t rights, int is_suser, boolean_t *found_deny,
int noimmutable, int parent_authorized_for_delete_child)
{
int result;
/*
* Check for immutability.
*
* In the deletion case, parent directory immutability vetoes specific
* file rights.
*/
if ((result = vnode_authorize_checkimmutable(mp, vcp, vcp->vap, rights,
noimmutable)) != 0) {
goto out;
}
if ((rights & KAUTH_VNODE_DELETE) &&
!parent_authorized_for_delete_child) {
result = vnode_authorize_checkimmutable(mp, vcp, vcp->dvap,
KAUTH_VNODE_DELETE_CHILD, 0);
if (result) {
goto out;
}
}
/*
* Clear rights that have been authorized by reaching this point, bail if nothing left to
* check.
*/
rights &= ~(KAUTH_VNODE_LINKTARGET | KAUTH_VNODE_CHECKIMMUTABLE);
if (rights == 0) {
goto out;
}
/*
* If we're not the superuser, authorize based on file properties;
* note that even if parent_authorized_for_delete_child is TRUE, we
* need to check on the node itself.
*/
if (!is_suser) {
/* process delete rights */
if ((rights & KAUTH_VNODE_DELETE) &&
((result = vnode_authorize_delete(vcp, parent_authorized_for_delete_child)) != 0)) {
goto out;
}
/* process remaining rights */
if ((rights & ~KAUTH_VNODE_DELETE) &&
(result = vnode_authorize_simple(vcp, rights, rights & KAUTH_VNODE_DELETE, found_deny)) != 0) {
goto out;
}
} else {
/*
* Execute is only granted to root if one of the x bits is set. This check only
* makes sense if the posix mode bits are actually supported.
*/
if ((rights & KAUTH_VNODE_EXECUTE) &&
(vcp->vap->va_type == VREG) &&
VATTR_IS_SUPPORTED(vcp->vap, va_mode) &&
!(vcp->vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH))) {
result = EPERM;
KAUTH_DEBUG("%p DENIED - root execute requires at least one x bit in 0x%x", vcp, vcp->vap->va_mode);
goto out;
}
/* Assume that there were DENYs so we don't wrongly cache KAUTH_VNODE_SEARCHBYANYONE */
*found_deny = TRUE;
KAUTH_DEBUG("%p ALLOWED - caller is superuser", vcp);
}
out:
return result;
}
static int
vnode_authorize_callback_int(kauth_action_t action, vfs_context_t ctx,
vnode_t vp, vnode_t dvp, int *errorp)
{
struct _vnode_authorize_context auth_context;
vauth_ctx vcp;
kauth_cred_t cred;
kauth_ace_rights_t rights;
struct vnode_attr va, dva;
int result;
int noimmutable;
boolean_t parent_authorized_for_delete_child = FALSE;
boolean_t found_deny = FALSE;
boolean_t parent_ref = FALSE;
boolean_t is_suser = FALSE;
vcp = &auth_context;
vcp->ctx = ctx;
vcp->vp = vp;
vcp->dvp = dvp;
/*
* Note that we authorize against the context, not the passed cred
* (the same thing anyway)
*/
cred = ctx->vc_ucred;
VATTR_INIT(&va);
vcp->vap = &va;
VATTR_INIT(&dva);
vcp->dvap = &dva;
vcp->flags = vcp->flags_valid = 0;
#if DIAGNOSTIC
if ((ctx == NULL) || (vp == NULL) || (cred == NULL)) {
panic("vnode_authorize: bad arguments (context %p vp %p cred %p)", ctx, vp, cred);
}
#endif
KAUTH_DEBUG("%p AUTH - %s %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s on %s '%s' (0x%x:%p/%p)",
vp, vfs_context_proc(ctx)->p_comm,
(action & KAUTH_VNODE_ACCESS) ? "access" : "auth",
(action & KAUTH_VNODE_READ_DATA) ? vnode_isdir(vp) ? " LIST_DIRECTORY" : " READ_DATA" : "",
(action & KAUTH_VNODE_WRITE_DATA) ? vnode_isdir(vp) ? " ADD_FILE" : " WRITE_DATA" : "",
(action & KAUTH_VNODE_EXECUTE) ? vnode_isdir(vp) ? " SEARCH" : " EXECUTE" : "",
(action & KAUTH_VNODE_DELETE) ? " DELETE" : "",
(action & KAUTH_VNODE_APPEND_DATA) ? vnode_isdir(vp) ? " ADD_SUBDIRECTORY" : " APPEND_DATA" : "",
(action & KAUTH_VNODE_DELETE_CHILD) ? " DELETE_CHILD" : "",
(action & KAUTH_VNODE_READ_ATTRIBUTES) ? " READ_ATTRIBUTES" : "",
(action & KAUTH_VNODE_WRITE_ATTRIBUTES) ? " WRITE_ATTRIBUTES" : "",
(action & KAUTH_VNODE_READ_EXTATTRIBUTES) ? " READ_EXTATTRIBUTES" : "",
(action & KAUTH_VNODE_WRITE_EXTATTRIBUTES) ? " WRITE_EXTATTRIBUTES" : "",
(action & KAUTH_VNODE_READ_SECURITY) ? " READ_SECURITY" : "",
(action & KAUTH_VNODE_WRITE_SECURITY) ? " WRITE_SECURITY" : "",
(action & KAUTH_VNODE_CHANGE_OWNER) ? " CHANGE_OWNER" : "",
(action & KAUTH_VNODE_NOIMMUTABLE) ? " (noimmutable)" : "",
vnode_isdir(vp) ? "directory" : "file",
vp->v_name ? vp->v_name : "<NULL>", action, vp, dvp);
/*
* Extract the control bits from the action, everything else is
* requested rights.
*/
noimmutable = (action & KAUTH_VNODE_NOIMMUTABLE) ? 1 : 0;
rights = action & ~(KAUTH_VNODE_ACCESS | KAUTH_VNODE_NOIMMUTABLE);
if (rights & KAUTH_VNODE_DELETE) {
#if DIAGNOSTIC
if (dvp == NULL) {
panic("vnode_authorize: KAUTH_VNODE_DELETE test requires a directory");
}
#endif
/*
* check to see if we've already authorized the parent
* directory for deletion of its children... if so, we
* can skip a whole bunch of work... we will still have to
* authorize that this specific child can be removed
*/
if (vnode_cache_is_authorized(dvp, ctx, KAUTH_VNODE_DELETE_CHILD) == TRUE) {
parent_authorized_for_delete_child = TRUE;
}
} else {
vcp->dvp = NULLVP;
vcp->dvap = NULL;
}
/*
* Check for read-only filesystems.
*/
if ((rights & KAUTH_VNODE_WRITE_RIGHTS) &&
(vp->v_mount->mnt_flag & MNT_RDONLY) &&
((vp->v_type == VREG) || (vp->v_type == VDIR) ||
(vp->v_type == VLNK) || (vp->v_type == VCPLX) ||
(rights & KAUTH_VNODE_DELETE) || (rights & KAUTH_VNODE_DELETE_CHILD))) {
result = EROFS;
goto out;
}
/*
* Check for noexec filesystems.
*/
if ((rights & KAUTH_VNODE_EXECUTE) && (vp->v_type == VREG) && (vp->v_mount->mnt_flag & MNT_NOEXEC)) {
result = EACCES;
goto out;
}
/*
* Handle cases related to filesystems with non-local enforcement.
* This call can return 0, in which case we will fall through to perform a
* check based on VNOP_GETATTR data. Otherwise it returns 1 and sets
* an appropriate result, at which point we can return immediately.
*/
if ((vp->v_mount->mnt_kern_flag & MNTK_AUTH_OPAQUE) && vnode_authorize_opaque(vp, &result, action, ctx)) {
goto out;
}
/*
* If the vnode is a namedstream (extended attribute) data vnode (eg.
* a resource fork), *_DATA becomes *_EXTATTRIBUTES.
*/
if (vnode_isnamedstream(vp)) {
if (rights & KAUTH_VNODE_READ_DATA) {
rights &= ~KAUTH_VNODE_READ_DATA;
rights |= KAUTH_VNODE_READ_EXTATTRIBUTES;
}
if (rights & KAUTH_VNODE_WRITE_DATA) {
rights &= ~KAUTH_VNODE_WRITE_DATA;
rights |= KAUTH_VNODE_WRITE_EXTATTRIBUTES;
}
/*
* Point 'vp' to the namedstream's parent for ACL checking
*/
if ((vp->v_parent != NULL) &&
(vget_internal(vp->v_parent, 0, VNODE_NODEAD | VNODE_DRAINO) == 0)) {
parent_ref = TRUE;
vcp->vp = vp = vp->v_parent;
}
}
if (vfs_context_issuser(ctx)) {
/*
* if we're not asking for execute permissions or modifications,
* then we're done, this action is authorized.
*/
if (!(rights & (KAUTH_VNODE_EXECUTE | KAUTH_VNODE_WRITE_RIGHTS))) {
goto success;
}
is_suser = TRUE;
}
/*
* Get vnode attributes and extended security information for the vnode
* and directory if required.
*
* If we're root we only want mode bits and flags for checking
* execute and immutability.
*/
VATTR_WANTED(&va, va_mode);
VATTR_WANTED(&va, va_flags);
if (!is_suser) {
VATTR_WANTED(&va, va_uid);
VATTR_WANTED(&va, va_gid);
VATTR_WANTED(&va, va_acl);
}
if ((result = vnode_getattr(vp, &va, ctx)) != 0) {
KAUTH_DEBUG("%p ERROR - failed to get vnode attributes - %d", vp, result);
goto out;
}
VATTR_WANTED(&va, va_type);
VATTR_RETURN(&va, va_type, vnode_vtype(vp));
if (vcp->dvp) {
VATTR_WANTED(&dva, va_mode);
VATTR_WANTED(&dva, va_flags);
if (!is_suser) {
VATTR_WANTED(&dva, va_uid);
VATTR_WANTED(&dva, va_gid);
VATTR_WANTED(&dva, va_acl);
}
if ((result = vnode_getattr(vcp->dvp, &dva, ctx)) != 0) {
KAUTH_DEBUG("%p ERROR - failed to get directory vnode attributes - %d", vp, result);
goto out;
}
VATTR_WANTED(&dva, va_type);
VATTR_RETURN(&dva, va_type, vnode_vtype(vcp->dvp));
}
result = vnode_attr_authorize_internal(vcp, vp->v_mount, rights, is_suser,
&found_deny, noimmutable, parent_authorized_for_delete_child);
out:
if (VATTR_IS_SUPPORTED(&va, va_acl) && (va.va_acl != NULL)) {
kauth_acl_free(va.va_acl);
}
if (VATTR_IS_SUPPORTED(&dva, va_acl) && (dva.va_acl != NULL)) {
kauth_acl_free(dva.va_acl);
}
if (result) {
if (parent_ref) {
vnode_put(vp);
}
*errorp = result;
KAUTH_DEBUG("%p DENIED - auth denied", vp);
return KAUTH_RESULT_DENY;
}
if ((rights & KAUTH_VNODE_SEARCH) && found_deny == FALSE && vp->v_type == VDIR) {
/*
* if we were successfully granted the right to search this directory
* and there were NO ACL DENYs for search and the posix permissions also don't
* deny execute, we can synthesize a global right that allows anyone to
* traverse this directory during a pathname lookup without having to
* match the credential associated with this cache of rights.
*
* Note that we can correctly cache KAUTH_VNODE_SEARCHBYANYONE
* only if we actually check ACLs which we don't for root. As
* a workaround, the lookup fast path checks for root.
*/
if (!VATTR_IS_SUPPORTED(&va, va_mode) ||
((va.va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) ==
(S_IXUSR | S_IXGRP | S_IXOTH))) {
vnode_cache_authorized_action(vp, ctx, KAUTH_VNODE_SEARCHBYANYONE);
}
}
success:
if (parent_ref) {
vnode_put(vp);
}
/*
* Note that this implies that we will allow requests for no rights, as well as
* for rights that we do not recognise. There should be none of these.
*/
KAUTH_DEBUG("%p ALLOWED - auth granted", vp);
return KAUTH_RESULT_ALLOW;
}
int
vnode_attr_authorize_init(struct vnode_attr *vap, struct vnode_attr *dvap,
kauth_action_t action, vfs_context_t ctx)
{
VATTR_INIT(vap);
VATTR_WANTED(vap, va_type);
VATTR_WANTED(vap, va_mode);
VATTR_WANTED(vap, va_flags);
if (dvap) {
VATTR_INIT(dvap);
if (action & KAUTH_VNODE_DELETE) {
VATTR_WANTED(dvap, va_type);
VATTR_WANTED(dvap, va_mode);
VATTR_WANTED(dvap, va_flags);
}
} else if (action & KAUTH_VNODE_DELETE) {
return EINVAL;
}
if (!vfs_context_issuser(ctx)) {
VATTR_WANTED(vap, va_uid);
VATTR_WANTED(vap, va_gid);
VATTR_WANTED(vap, va_acl);
if (dvap && (action & KAUTH_VNODE_DELETE)) {
VATTR_WANTED(dvap, va_uid);
VATTR_WANTED(dvap, va_gid);
VATTR_WANTED(dvap, va_acl);
}
}
return 0;
}
#define VNODE_SEC_ATTRS_NO_ACL (VNODE_ATTR_va_uid | VNODE_ATTR_va_gid | VNODE_ATTR_va_mode | VNODE_ATTR_va_flags | VNODE_ATTR_va_type)
int
vnode_attr_authorize(struct vnode_attr *vap, struct vnode_attr *dvap, mount_t mp,
kauth_action_t action, vfs_context_t ctx)
{
struct _vnode_authorize_context auth_context;
vauth_ctx vcp;
kauth_ace_rights_t rights;
int noimmutable;
boolean_t found_deny;
boolean_t is_suser = FALSE;
int result = 0;
uid_t ouid = vap->va_uid;
gid_t ogid = vap->va_gid;
vcp = &auth_context;
vcp->ctx = ctx;
vcp->vp = NULLVP;
vcp->vap = vap;
vcp->dvp = NULLVP;
vcp->dvap = dvap;
vcp->flags = vcp->flags_valid = 0;
noimmutable = (action & KAUTH_VNODE_NOIMMUTABLE) ? 1 : 0;
rights = action & ~(KAUTH_VNODE_ACCESS | KAUTH_VNODE_NOIMMUTABLE);
/*
* Check for read-only filesystems.
*/
if ((rights & KAUTH_VNODE_WRITE_RIGHTS) &&
mp && (mp->mnt_flag & MNT_RDONLY) &&
((vap->va_type == VREG) || (vap->va_type == VDIR) ||
(vap->va_type == VLNK) || (rights & KAUTH_VNODE_DELETE) ||
(rights & KAUTH_VNODE_DELETE_CHILD))) {
result = EROFS;
goto out;
}
/*
* Check for noexec filesystems.
*/
if ((rights & KAUTH_VNODE_EXECUTE) &&
(vap->va_type == VREG) && mp && (mp->mnt_flag & MNT_NOEXEC)) {
result = EACCES;
goto out;
}
if (vfs_context_issuser(ctx)) {
/*
* if we're not asking for execute permissions or modifications,
* then we're done, this action is authorized.
*/
if (!(rights & (KAUTH_VNODE_EXECUTE | KAUTH_VNODE_WRITE_RIGHTS))) {
goto out;
}
is_suser = TRUE;
}
if (mp) {
if (vfs_extendedsecurity(mp) && VATTR_IS_ACTIVE(vap, va_acl) && !VATTR_IS_SUPPORTED(vap, va_acl)) {
panic("(1) vnode attrs not complete for vnode_attr_authorize");
}
vnode_attr_handle_uid_and_gid(vap, mp, ctx);
}
if ((vap->va_active & VNODE_SEC_ATTRS_NO_ACL) != (vap->va_supported & VNODE_SEC_ATTRS_NO_ACL)) {
panic("(2) vnode attrs not complete for vnode_attr_authorize (2) vap->va_active = 0x%llx , vap->va_supported = 0x%llx",
vap->va_active, vap->va_supported);
}
result = vnode_attr_authorize_internal(vcp, mp, rights, is_suser,
&found_deny, noimmutable, FALSE);
if (mp) {
vap->va_uid = ouid;
vap->va_gid = ogid;
}
if (result == EPERM) {
result = EACCES;
}
out:
return result;
}
int
vnode_authattr_new(vnode_t dvp, struct vnode_attr *vap, int noauth, vfs_context_t ctx)
{
return vnode_authattr_new_internal(dvp, vap, noauth, NULL, ctx);
}
/*
* Check that the attribute information in vattr can be legally applied to
* a new file by the context.
*/
static int
vnode_authattr_new_internal(vnode_t dvp, struct vnode_attr *vap, int noauth, uint32_t *defaulted_fieldsp, vfs_context_t ctx)
{
int error;
int has_priv_suser, ismember, defaulted_owner, defaulted_group, defaulted_mode;
uint32_t inherit_flags;
kauth_cred_t cred;
guid_t changer;
mount_t dmp;
struct vnode_attr dva;
error = 0;
if (defaulted_fieldsp) {
*defaulted_fieldsp = 0;
}
defaulted_owner = defaulted_group = defaulted_mode = 0;
inherit_flags = 0;
/*
* Require that the filesystem support extended security to apply any.
*/
if (!vfs_extendedsecurity(dvp->v_mount) &&
(VATTR_IS_ACTIVE(vap, va_acl) || VATTR_IS_ACTIVE(vap, va_uuuid) || VATTR_IS_ACTIVE(vap, va_guuid))) {
error = EINVAL;
goto out;
}
/*
* Default some fields.
*/
dmp = dvp->v_mount;
/*
* If the filesystem is mounted IGNORE_OWNERSHIP and an explicit owner is set, that
* owner takes ownership of all new files.
*/
if ((dmp->mnt_flag & MNT_IGNORE_OWNERSHIP) && (dmp->mnt_fsowner != KAUTH_UID_NONE)) {
VATTR_SET(vap, va_uid, dmp->mnt_fsowner);
defaulted_owner = 1;
} else {
if (!VATTR_IS_ACTIVE(vap, va_uid)) {
/* default owner is current user */
VATTR_SET(vap, va_uid, kauth_cred_getuid(vfs_context_ucred(ctx)));
defaulted_owner = 1;
}
}
/*
* We need the dvp's va_flags and *may* need the gid of the directory,
* we ask for both here.
*/
VATTR_INIT(&dva);
VATTR_WANTED(&dva, va_gid);
VATTR_WANTED(&dva, va_flags);
if ((error = vnode_getattr(dvp, &dva, ctx)) != 0) {
goto out;
}
/*
* If the filesystem is mounted IGNORE_OWNERSHIP and an explicit grouo is set, that
* group takes ownership of all new files.
*/
if ((dmp->mnt_flag & MNT_IGNORE_OWNERSHIP) && (dmp->mnt_fsgroup != KAUTH_GID_NONE)) {
VATTR_SET(vap, va_gid, dmp->mnt_fsgroup);
defaulted_group = 1;
} else {
if (!VATTR_IS_ACTIVE(vap, va_gid)) {
/* default group comes from parent object, fallback to current user */
if (VATTR_IS_SUPPORTED(&dva, va_gid)) {
VATTR_SET(vap, va_gid, dva.va_gid);
} else {
VATTR_SET(vap, va_gid, kauth_cred_getgid(vfs_context_ucred(ctx)));
}
defaulted_group = 1;
}
}
if (!VATTR_IS_ACTIVE(vap, va_flags)) {
VATTR_SET(vap, va_flags, 0);
}
/* Determine if SF_RESTRICTED should be inherited from the parent
* directory. */
if (VATTR_IS_SUPPORTED(&dva, va_flags)) {
inherit_flags = dva.va_flags & (UF_DATAVAULT | SF_RESTRICTED);
}
/* default mode is everything, masked with current umask */
if (!VATTR_IS_ACTIVE(vap, va_mode)) {
VATTR_SET(vap, va_mode, ACCESSPERMS & ~vfs_context_proc(ctx)->p_fd.fd_cmask);
KAUTH_DEBUG("ATTR - defaulting new file mode to %o from umask %o",
vap->va_mode, vfs_context_proc(ctx)->p_fd.fd_cmask);
defaulted_mode = 1;
}
/* set timestamps to now */
if (!VATTR_IS_ACTIVE(vap, va_create_time)) {
nanotime(&vap->va_create_time);
VATTR_SET_ACTIVE(vap, va_create_time);
}
/*
* Check for attempts to set nonsensical fields.
*/
if (vap->va_active & ~VNODE_ATTR_NEWOBJ) {
error = EINVAL;
KAUTH_DEBUG("ATTR - ERROR - attempt to set unsupported new-file attributes %llx",
vap->va_active & ~VNODE_ATTR_NEWOBJ);
goto out;
}
/*
* Quickly check for the applicability of any enforcement here.
* Tests below maintain the integrity of the local security model.
*/
if (vfs_authopaque(dvp->v_mount)) {
goto out;
}
/*
* We need to know if the caller is the superuser, or if the work is
* otherwise already authorised.
*/
cred = vfs_context_ucred(ctx);
if (noauth) {
/* doing work for the kernel */
has_priv_suser = 1;
} else {
has_priv_suser = vfs_context_issuser(ctx);
}
if (VATTR_IS_ACTIVE(vap, va_flags)) {
vap->va_flags &= ~SF_SYNTHETIC;
if (has_priv_suser) {
if ((vap->va_flags & (UF_SETTABLE | SF_SETTABLE)) != vap->va_flags) {
error = EPERM;
KAUTH_DEBUG(" DENIED - superuser attempt to set illegal flag(s)");
goto out;
}
} else {
if ((vap->va_flags & UF_SETTABLE) != vap->va_flags) {
error = EPERM;
KAUTH_DEBUG(" DENIED - user attempt to set illegal flag(s)");
goto out;
}
}
}
/* if not superuser, validate legality of new-item attributes */
if (!has_priv_suser) {
if (!defaulted_mode && VATTR_IS_ACTIVE(vap, va_mode)) {
/* setgid? */
if (vap->va_mode & S_ISGID) {
if ((error = kauth_cred_ismember_gid(cred, vap->va_gid, &ismember)) != 0) {
KAUTH_DEBUG("ATTR - ERROR: got %d checking for membership in %d", error, vap->va_gid);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" DENIED - can't set SGID bit, not a member of %d", vap->va_gid);
error = EPERM;
goto out;
}
}
/* setuid? */
if ((vap->va_mode & S_ISUID) && (vap->va_uid != kauth_cred_getuid(cred))) {
KAUTH_DEBUG("ATTR - ERROR: illegal attempt to set the setuid bit");
error = EPERM;
goto out;
}
}
if (!defaulted_owner && (vap->va_uid != kauth_cred_getuid(cred))) {
KAUTH_DEBUG(" DENIED - cannot create new item owned by %d", vap->va_uid);
error = EPERM;
goto out;
}
if (!defaulted_group) {
if ((error = kauth_cred_ismember_gid(cred, vap->va_gid, &ismember)) != 0) {
KAUTH_DEBUG(" ERROR - got %d checking for membership in %d", error, vap->va_gid);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" DENIED - cannot create new item with group %d - not a member", vap->va_gid);
error = EPERM;
goto out;
}
}
/* initialising owner/group UUID */
if (VATTR_IS_ACTIVE(vap, va_uuuid)) {
if ((error = kauth_cred_getguid(cred, &changer)) != 0) {
KAUTH_DEBUG(" ERROR - got %d trying to get caller UUID", error);
/* XXX ENOENT here - no GUID - should perhaps become EPERM */
goto out;
}
if (!kauth_guid_equal(&vap->va_uuuid, &changer)) {
KAUTH_DEBUG(" ERROR - cannot create item with supplied owner UUID - not us");
error = EPERM;
goto out;
}
}
if (VATTR_IS_ACTIVE(vap, va_guuid)) {
if ((error = kauth_cred_ismember_guid(cred, &vap->va_guuid, &ismember)) != 0) {
KAUTH_DEBUG(" ERROR - got %d trying to check group membership", error);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" ERROR - cannot create item with supplied group UUID - not a member");
error = EPERM;
goto out;
}
}
}
out:
if (inherit_flags) {
/* Apply SF_RESTRICTED to the file if its parent directory was
* restricted. This is done at the end so that root is not
* required if this flag is only set due to inheritance. */
VATTR_SET(vap, va_flags, (vap->va_flags | inherit_flags));
}
if (defaulted_fieldsp) {
if (defaulted_mode) {
*defaulted_fieldsp |= VATTR_PREPARE_DEFAULTED_MODE;
}
if (defaulted_group) {
*defaulted_fieldsp |= VATTR_PREPARE_DEFAULTED_GID;
}
if (defaulted_owner) {
*defaulted_fieldsp |= VATTR_PREPARE_DEFAULTED_UID;
}
}
return error;
}
/*
* Check that the attribute information in vap can be legally written by the
* context.
*
* Call this when you're not sure about the vnode_attr; either its contents
* have come from an unknown source, or when they are variable.
*
* Returns errno, or zero and sets *actionp to the KAUTH_VNODE_* actions that
* must be authorized to be permitted to write the vattr.
*/
int
vnode_authattr(vnode_t vp, struct vnode_attr *vap, kauth_action_t *actionp, vfs_context_t ctx)
{
struct vnode_attr ova;
kauth_action_t required_action;
int error, has_priv_suser, ismember, chowner, chgroup, clear_suid, clear_sgid;
guid_t changer;
gid_t group;
uid_t owner;
mode_t newmode;
kauth_cred_t cred;
uint32_t fdelta;
VATTR_INIT(&ova);
required_action = 0;
error = 0;
/*
* Quickly check for enforcement applicability.
*/
if (vfs_authopaque(vp->v_mount)) {
goto out;
}
/*
* Check for attempts to set nonsensical fields.
*/
if (vap->va_active & VNODE_ATTR_RDONLY) {
KAUTH_DEBUG("ATTR - ERROR: attempt to set readonly attribute(s)");
error = EINVAL;
goto out;
}
/*
* We need to know if the caller is the superuser.
*/
cred = vfs_context_ucred(ctx);
has_priv_suser = kauth_cred_issuser(cred);
/*
* If any of the following are changing, we need information from the old file:
* va_uid
* va_gid
* va_mode
* va_uuuid
* va_guuid
*/
if (VATTR_IS_ACTIVE(vap, va_uid) ||
VATTR_IS_ACTIVE(vap, va_gid) ||
VATTR_IS_ACTIVE(vap, va_mode) ||
VATTR_IS_ACTIVE(vap, va_uuuid) ||
VATTR_IS_ACTIVE(vap, va_guuid)) {
VATTR_WANTED(&ova, va_mode);
VATTR_WANTED(&ova, va_uid);
VATTR_WANTED(&ova, va_gid);
VATTR_WANTED(&ova, va_uuuid);
VATTR_WANTED(&ova, va_guuid);
KAUTH_DEBUG("ATTR - security information changing, fetching existing attributes");
}
/*
* If timestamps are being changed, we need to know who the file is owned
* by.
*/
if (VATTR_IS_ACTIVE(vap, va_create_time) ||
VATTR_IS_ACTIVE(vap, va_change_time) ||
VATTR_IS_ACTIVE(vap, va_modify_time) ||
VATTR_IS_ACTIVE(vap, va_access_time) ||
VATTR_IS_ACTIVE(vap, va_backup_time) ||
VATTR_IS_ACTIVE(vap, va_addedtime)) {
VATTR_WANTED(&ova, va_uid);
#if 0 /* enable this when we support UUIDs as official owners */
VATTR_WANTED(&ova, va_uuuid);
#endif
KAUTH_DEBUG("ATTR - timestamps changing, fetching uid and GUID");
}
/*
* If flags are being changed, we need the old flags.
*/
if (VATTR_IS_ACTIVE(vap, va_flags)) {
KAUTH_DEBUG("ATTR - flags changing, fetching old flags");
VATTR_WANTED(&ova, va_flags);
}
/*
* If ACLs are being changed, we need the old ACLs.
*/
if (VATTR_IS_ACTIVE(vap, va_acl)) {
KAUTH_DEBUG("ATTR - acl changing, fetching old flags");
VATTR_WANTED(&ova, va_acl);
}
/*
* If the size is being set, make sure it's not a directory.
*/
if (VATTR_IS_ACTIVE(vap, va_data_size)) {
/* size is only meaningful on regular files, don't permit otherwise */
if (!vnode_isreg(vp)) {
KAUTH_DEBUG("ATTR - ERROR: size change requested on non-file");
error = vnode_isdir(vp) ? EISDIR : EINVAL;
goto out;
}
}
/*
* Get old data.
*/
KAUTH_DEBUG("ATTR - fetching old attributes %016llx", ova.va_active);
if ((error = vnode_getattr(vp, &ova, ctx)) != 0) {
KAUTH_DEBUG(" ERROR - got %d trying to get attributes", error);
goto out;
}
/*
* Size changes require write access to the file data.
*/
if (VATTR_IS_ACTIVE(vap, va_data_size)) {
/* if we can't get the size, or it's different, we need write access */
KAUTH_DEBUG("ATTR - size change, requiring WRITE_DATA");
required_action |= KAUTH_VNODE_WRITE_DATA;
}
/*
* Changing timestamps?
*
* Note that we are only called to authorize user-requested time changes;
* side-effect time changes are not authorized. Authorisation is only
* required for existing files.
*
* Non-owners are not permitted to change the time on an existing
* file to anything other than the current time.
*/
if (VATTR_IS_ACTIVE(vap, va_create_time) ||
VATTR_IS_ACTIVE(vap, va_change_time) ||
VATTR_IS_ACTIVE(vap, va_modify_time) ||
VATTR_IS_ACTIVE(vap, va_access_time) ||
VATTR_IS_ACTIVE(vap, va_backup_time) ||
VATTR_IS_ACTIVE(vap, va_addedtime)) {
/*
* The owner and root may set any timestamps they like,
* provided that the file is not immutable. The owner still needs
* WRITE_ATTRIBUTES (implied by ownership but still deniable).
*/
if (has_priv_suser || vauth_node_owner(&ova, cred)) {
KAUTH_DEBUG("ATTR - root or owner changing timestamps");
required_action |= KAUTH_VNODE_CHECKIMMUTABLE | KAUTH_VNODE_WRITE_ATTRIBUTES;
} else {
/* just setting the current time? */
if (vap->va_vaflags & VA_UTIMES_NULL) {
KAUTH_DEBUG("ATTR - non-root/owner changing timestamps, requiring WRITE_ATTRIBUTES");
required_action |= KAUTH_VNODE_WRITE_ATTRIBUTES;
} else {
KAUTH_DEBUG("ATTR - ERROR: illegal timestamp modification attempted");
error = EACCES;
goto out;
}
}
}
/*
* Changing file mode?
*/
if (VATTR_IS_ACTIVE(vap, va_mode) && VATTR_IS_SUPPORTED(&ova, va_mode) && (ova.va_mode != vap->va_mode)) {
KAUTH_DEBUG("ATTR - mode change from %06o to %06o", ova.va_mode, vap->va_mode);
/*
* Mode changes always have the same basic auth requirements.
*/
if (has_priv_suser) {
KAUTH_DEBUG("ATTR - superuser mode change, requiring immutability check");
required_action |= KAUTH_VNODE_CHECKIMMUTABLE;
} else {
/* need WRITE_SECURITY */
KAUTH_DEBUG("ATTR - non-superuser mode change, requiring WRITE_SECURITY");
required_action |= KAUTH_VNODE_WRITE_SECURITY;
}
/*
* Can't set the setgid bit if you're not in the group and not root. Have to have
* existing group information in the case we're not setting it right now.
*/
if (vap->va_mode & S_ISGID) {
required_action |= KAUTH_VNODE_CHECKIMMUTABLE; /* always required */
if (!has_priv_suser) {
if (VATTR_IS_ACTIVE(vap, va_gid)) {
group = vap->va_gid;
} else if (VATTR_IS_SUPPORTED(&ova, va_gid)) {
group = ova.va_gid;
} else {
KAUTH_DEBUG("ATTR - ERROR: setgid but no gid available");
error = EINVAL;
goto out;
}
/*
* This might be too restrictive; WRITE_SECURITY might be implied by
* membership in this case, rather than being an additional requirement.
*/
if ((error = kauth_cred_ismember_gid(cred, group, &ismember)) != 0) {
KAUTH_DEBUG("ATTR - ERROR: got %d checking for membership in %d", error, vap->va_gid);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" DENIED - can't set SGID bit, not a member of %d", group);
error = EPERM;
goto out;
}
}
}
/*
* Can't set the setuid bit unless you're root or the file's owner.
*/
if (vap->va_mode & S_ISUID) {
required_action |= KAUTH_VNODE_CHECKIMMUTABLE; /* always required */
if (!has_priv_suser) {
if (VATTR_IS_ACTIVE(vap, va_uid)) {
owner = vap->va_uid;
} else if (VATTR_IS_SUPPORTED(&ova, va_uid)) {
owner = ova.va_uid;
} else {
KAUTH_DEBUG("ATTR - ERROR: setuid but no uid available");
error = EINVAL;
goto out;
}
if (owner != kauth_cred_getuid(cred)) {
/*
* We could allow this if WRITE_SECURITY is permitted, perhaps.
*/
KAUTH_DEBUG("ATTR - ERROR: illegal attempt to set the setuid bit");
error = EPERM;
goto out;
}
}
}
}
/*
* Validate/mask flags changes. This checks that only the flags in
* the UF_SETTABLE mask are being set, and preserves the flags in
* the SF_SETTABLE case.
*
* Since flags changes may be made in conjunction with other changes,
* we will ask the auth code to ignore immutability in the case that
* the SF_* flags are not set and we are only manipulating the file flags.
*
*/
if (VATTR_IS_ACTIVE(vap, va_flags)) {
/* compute changing flags bits */
vap->va_flags &= ~SF_SYNTHETIC;
ova.va_flags &= ~SF_SYNTHETIC;
if (VATTR_IS_SUPPORTED(&ova, va_flags)) {
fdelta = vap->va_flags ^ ova.va_flags;
} else {
fdelta = vap->va_flags;
}
if (fdelta != 0) {
KAUTH_DEBUG("ATTR - flags changing, requiring WRITE_SECURITY");
required_action |= KAUTH_VNODE_WRITE_SECURITY;
/* check that changing bits are legal */
if (has_priv_suser) {
/*
* The immutability check will prevent us from clearing the SF_*
* flags unless the system securelevel permits it, so just check
* for legal flags here.
*/
if (fdelta & ~(UF_SETTABLE | SF_SETTABLE)) {
error = EPERM;
KAUTH_DEBUG(" DENIED - superuser attempt to set illegal flag(s)");
goto out;
}
} else {
if (fdelta & ~UF_SETTABLE) {
error = EPERM;
KAUTH_DEBUG(" DENIED - user attempt to set illegal flag(s)");
goto out;
}
}
/*
* If the caller has the ability to manipulate file flags,
* security is not reduced by ignoring them for this operation.
*
* A more complete test here would consider the 'after' states of the flags
* to determine whether it would permit the operation, but this becomes
* very complex.
*
* Ignoring immutability is conditional on securelevel; this does not bypass
* the SF_* flags if securelevel > 0.
*/
required_action |= KAUTH_VNODE_NOIMMUTABLE;
}
}
/*
* Validate ownership information.
*/
chowner = 0;
chgroup = 0;
clear_suid = 0;
clear_sgid = 0;
/*
* uid changing
* Note that if the filesystem didn't give us a UID, we expect that it doesn't
* support them in general, and will ignore it if/when we try to set it.
* We might want to clear the uid out of vap completely here.
*/
if (VATTR_IS_ACTIVE(vap, va_uid)) {
if (VATTR_IS_SUPPORTED(&ova, va_uid) && (vap->va_uid != ova.va_uid)) {
if (!has_priv_suser && (kauth_cred_getuid(cred) != vap->va_uid)) {
KAUTH_DEBUG(" DENIED - non-superuser cannot change ownershipt to a third party");
error = EPERM;
goto out;
}
chowner = 1;
}
clear_suid = 1;
}
/*
* gid changing
* Note that if the filesystem didn't give us a GID, we expect that it doesn't
* support them in general, and will ignore it if/when we try to set it.
* We might want to clear the gid out of vap completely here.
*/
if (VATTR_IS_ACTIVE(vap, va_gid)) {
if (VATTR_IS_SUPPORTED(&ova, va_gid) && (vap->va_gid != ova.va_gid)) {
if (!has_priv_suser) {
if ((error = kauth_cred_ismember_gid(cred, vap->va_gid, &ismember)) != 0) {
KAUTH_DEBUG(" ERROR - got %d checking for membership in %d", error, vap->va_gid);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" DENIED - group change from %d to %d but not a member of target group",
ova.va_gid, vap->va_gid);
error = EPERM;
goto out;
}
}
chgroup = 1;
}
clear_sgid = 1;
}
/*
* Owner UUID being set or changed.
*/
if (VATTR_IS_ACTIVE(vap, va_uuuid)) {
/* if the owner UUID is not actually changing ... */
if (VATTR_IS_SUPPORTED(&ova, va_uuuid)) {
if (kauth_guid_equal(&vap->va_uuuid, &ova.va_uuuid)) {
goto no_uuuid_change;
}
/*
* If the current owner UUID is a null GUID, check
* it against the UUID corresponding to the owner UID.
*/
if (kauth_guid_equal(&ova.va_uuuid, &kauth_null_guid) &&
VATTR_IS_SUPPORTED(&ova, va_uid)) {
guid_t uid_guid;
if (kauth_cred_uid2guid(ova.va_uid, &uid_guid) == 0 &&
kauth_guid_equal(&vap->va_uuuid, &uid_guid)) {
goto no_uuuid_change;
}
}
}
/*
* The owner UUID cannot be set by a non-superuser to anything other than
* their own or a null GUID (to "unset" the owner UUID).
* Note that file systems must be prepared to handle the
* null UUID case in a manner appropriate for that file
* system.
*/
if (!has_priv_suser) {
if ((error = kauth_cred_getguid(cred, &changer)) != 0) {
KAUTH_DEBUG(" ERROR - got %d trying to get caller UUID", error);
/* XXX ENOENT here - no UUID - should perhaps become EPERM */
goto out;
}
if (!kauth_guid_equal(&vap->va_uuuid, &changer) &&
!kauth_guid_equal(&vap->va_uuuid, &kauth_null_guid)) {
KAUTH_DEBUG(" ERROR - cannot set supplied owner UUID - not us / null");
error = EPERM;
goto out;
}
}
chowner = 1;
clear_suid = 1;
}
no_uuuid_change:
/*
* Group UUID being set or changed.
*/
if (VATTR_IS_ACTIVE(vap, va_guuid)) {
/* if the group UUID is not actually changing ... */
if (VATTR_IS_SUPPORTED(&ova, va_guuid)) {
if (kauth_guid_equal(&vap->va_guuid, &ova.va_guuid)) {
goto no_guuid_change;
}
/*
* If the current group UUID is a null UUID, check
* it against the UUID corresponding to the group GID.
*/
if (kauth_guid_equal(&ova.va_guuid, &kauth_null_guid) &&
VATTR_IS_SUPPORTED(&ova, va_gid)) {
guid_t gid_guid;
if (kauth_cred_gid2guid(ova.va_gid, &gid_guid) == 0 &&
kauth_guid_equal(&vap->va_guuid, &gid_guid)) {
goto no_guuid_change;
}
}
}
/*
* The group UUID cannot be set by a non-superuser to anything other than
* one of which they are a member or a null GUID (to "unset"
* the group UUID).
* Note that file systems must be prepared to handle the
* null UUID case in a manner appropriate for that file
* system.
*/
if (!has_priv_suser) {
if (kauth_guid_equal(&vap->va_guuid, &kauth_null_guid)) {
ismember = 1;
} else if ((error = kauth_cred_ismember_guid(cred, &vap->va_guuid, &ismember)) != 0) {
KAUTH_DEBUG(" ERROR - got %d trying to check group membership", error);
goto out;
}
if (!ismember) {
KAUTH_DEBUG(" ERROR - cannot set supplied group UUID - not a member / null");
error = EPERM;
goto out;
}
}
chgroup = 1;
}
no_guuid_change:
/*
* Compute authorisation for group/ownership changes.
*/
if (chowner || chgroup || clear_suid || clear_sgid) {
if (has_priv_suser) {
KAUTH_DEBUG("ATTR - superuser changing file owner/group, requiring immutability check");
required_action |= KAUTH_VNODE_CHECKIMMUTABLE;
} else {
if (chowner) {
KAUTH_DEBUG("ATTR - ownership change, requiring TAKE_OWNERSHIP");
required_action |= KAUTH_VNODE_TAKE_OWNERSHIP;
}
if (chgroup && !chowner) {
KAUTH_DEBUG("ATTR - group change, requiring WRITE_SECURITY");
required_action |= KAUTH_VNODE_WRITE_SECURITY;
}
}
/*
* clear set-uid and set-gid bits. POSIX only requires this for
* non-privileged processes but we do it even for root.
*/
if (VATTR_IS_ACTIVE(vap, va_mode)) {
newmode = vap->va_mode;
} else if (VATTR_IS_SUPPORTED(&ova, va_mode)) {
newmode = ova.va_mode;
} else {
KAUTH_DEBUG("CHOWN - trying to change owner but cannot get mode from filesystem to mask setugid bits");
newmode = 0;
}
/* chown always clears setuid/gid bits. An exception is made for
* setattrlist which can set both at the same time: <uid, gid, mode> on a file:
* setattrlist is allowed to set the new mode on the file and change (chown)
* uid/gid.
*/
if (newmode & (S_ISUID | S_ISGID)) {
if (!VATTR_IS_ACTIVE(vap, va_mode)) {
KAUTH_DEBUG("CHOWN - masking setugid bits from mode %o to %o",
newmode, newmode & ~(S_ISUID | S_ISGID));
newmode &= ~(S_ISUID | S_ISGID);
}
VATTR_SET(vap, va_mode, newmode);
}
}
/*
* Authorise changes in the ACL.
*/
if (VATTR_IS_ACTIVE(vap, va_acl)) {
/* no existing ACL */
if (!VATTR_IS_ACTIVE(&ova, va_acl) || (ova.va_acl == NULL)) {
/* adding an ACL */
if (vap->va_acl != NULL) {
required_action |= KAUTH_VNODE_WRITE_SECURITY;
KAUTH_DEBUG("CHMOD - adding ACL");
}
/* removing an existing ACL */
} else if (vap->va_acl == NULL) {
required_action |= KAUTH_VNODE_WRITE_SECURITY;
KAUTH_DEBUG("CHMOD - removing ACL");
/* updating an existing ACL */
} else {
if (vap->va_acl->acl_entrycount != ova.va_acl->acl_entrycount) {
/* entry count changed, must be different */
required_action |= KAUTH_VNODE_WRITE_SECURITY;
KAUTH_DEBUG("CHMOD - adding/removing ACL entries");
} else if (vap->va_acl->acl_entrycount > 0) {
/* both ACLs have the same ACE count, said count is 1 or more, bitwise compare ACLs */
if (memcmp(&vap->va_acl->acl_ace[0], &ova.va_acl->acl_ace[0],
sizeof(struct kauth_ace) * vap->va_acl->acl_entrycount)) {
required_action |= KAUTH_VNODE_WRITE_SECURITY;
KAUTH_DEBUG("CHMOD - changing ACL entries");
}
}
}
}
/*
* Other attributes that require authorisation.
*/
if (VATTR_IS_ACTIVE(vap, va_encoding)) {
required_action |= KAUTH_VNODE_WRITE_ATTRIBUTES;
}
out:
if (VATTR_IS_SUPPORTED(&ova, va_acl) && (ova.va_acl != NULL)) {
kauth_acl_free(ova.va_acl);
}
if (error == 0) {
*actionp = required_action;
}
return error;
}
static int
setlocklocal_callback(struct vnode *vp, __unused void *cargs)
{
vnode_lock_spin(vp);
vp->v_flag |= VLOCKLOCAL;
vnode_unlock(vp);
return VNODE_RETURNED;
}
void
vfs_setlocklocal(mount_t mp)
{
mount_lock_spin(mp);
mp->mnt_kern_flag |= MNTK_LOCK_LOCAL;
mount_unlock(mp);
/*
* The number of active vnodes is expected to be
* very small when vfs_setlocklocal is invoked.
*/
vnode_iterate(mp, 0, setlocklocal_callback, NULL);
}
void
vfs_setcompoundopen(mount_t mp)
{
mount_lock_spin(mp);
mp->mnt_compound_ops |= COMPOUND_VNOP_OPEN;
mount_unlock(mp);
}
void
vnode_setswapmount(vnode_t vp)
{
mount_lock(vp->v_mount);
vp->v_mount->mnt_kern_flag |= MNTK_SWAP_MOUNT;
mount_unlock(vp->v_mount);
}
void
vfs_setfskit(mount_t mp)
{
mount_lock_spin(mp);
mp->mnt_kern_flag |= MNTK_FSKIT;
mount_unlock(mp);
}
char *
vfs_getfstypenameref_locked(mount_t mp, size_t *lenp)
{
char *name;
if (mp->mnt_kern_flag & MNTK_TYPENAME_OVERRIDE) {
name = mp->fstypename_override;
} else {
name = mp->mnt_vfsstat.f_fstypename;
}
if (lenp != NULL) {
*lenp = strlen(name);
}
return name;
}
void
vfs_getfstypename(mount_t mp, char *buf, size_t buflen)
{
mount_lock_spin(mp);
strlcpy(buf, vfs_getfstypenameref_locked(mp, NULL), buflen);
mount_unlock(mp);
}
void
vfs_setfstypename_locked(mount_t mp, const char *name)
{
if (name == NULL || name[0] == '\0') {
mp->mnt_kern_flag &= ~MNTK_TYPENAME_OVERRIDE;
mp->fstypename_override[0] = '\0';
} else {
strlcpy(mp->fstypename_override, name,
sizeof(mp->fstypename_override));
mp->mnt_kern_flag |= MNTK_TYPENAME_OVERRIDE;
}
}
void
vfs_setfstypename(mount_t mp, const char *name)
{
mount_lock_spin(mp);
vfs_setfstypename_locked(mp, name);
mount_unlock(mp);
}
int64_t
vnode_getswappin_avail(vnode_t vp)
{
int64_t max_swappin_avail = 0;
mount_lock(vp->v_mount);
if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_SWAPPIN_SUPPORTED) {
max_swappin_avail = vp->v_mount->mnt_max_swappin_available;
}
mount_unlock(vp->v_mount);
return max_swappin_avail;
}
void
vn_setunionwait(vnode_t vp)
{
vnode_lock_spin(vp);
vp->v_flag |= VISUNION;
vnode_unlock(vp);
}
void
vn_checkunionwait(vnode_t vp)
{
vnode_lock_spin(vp);
while ((vp->v_flag & VISUNION) == VISUNION) {
msleep((caddr_t)&vp->v_flag, &vp->v_lock, 0, 0, 0);
}
vnode_unlock(vp);
}
void
vn_clearunionwait(vnode_t vp, int locked)
{
if (!locked) {
vnode_lock_spin(vp);
}
if ((vp->v_flag & VISUNION) == VISUNION) {
vp->v_flag &= ~VISUNION;
wakeup((caddr_t)&vp->v_flag);
}
if (!locked) {
vnode_unlock(vp);
}
}
/*
* Removes orphaned apple double files during a rmdir
* Works by:
* 1. vnode_suspend().
* 2. Call VNOP_READDIR() till the end of directory is reached.
* 3. Check if the directory entries returned are regular files with name starting with "._". If not, return ENOTEMPTY.
* 4. Continue (2) and (3) till end of directory is reached.
* 5. If all the entries in the directory were files with "._" name, delete all the files.
* 6. vnode_resume()
* 7. If deletion of all files succeeded, call VNOP_RMDIR() again.
*/
errno_t
rmdir_remove_orphaned_appleDouble(vnode_t vp, vfs_context_t ctx, int * restart_flag)
{
#define UIO_BUFF_SIZE 2048
uio_t auio = NULL;
int eofflag, siz = UIO_BUFF_SIZE, alloc_size = 0, nentries = 0;
int open_flag = 0, full_erase_flag = 0;
UIO_STACKBUF(uio_buf, 1);
char *rbuf = NULL;
void *dir_pos;
void *dir_end;
struct dirent *dp;
errno_t error;
error = vnode_suspend(vp);
/*
* restart_flag is set so that the calling rmdir sleeps and resets
*/
if (error == EBUSY) {
*restart_flag = 1;
}
if (error != 0) {
return error;
}
/*
* Prevent dataless fault materialization while we have
* a suspended vnode.
*/
uthread_t ut = current_uthread();
bool saved_nodatalessfaults =
(ut->uu_flag & UT_NSPACE_NODATALESSFAULTS) ? true : false;
ut->uu_flag |= UT_NSPACE_NODATALESSFAULTS;
/*
* set up UIO
*/
rbuf = kalloc_data(siz, Z_WAITOK);
alloc_size = siz;
if (rbuf) {
auio = uio_createwithbuffer(1, 0, UIO_SYSSPACE, UIO_READ,
&uio_buf[0], sizeof(uio_buf));
}
if (!rbuf || !auio) {
error = ENOMEM;
goto outsc;
}
uio_setoffset(auio, 0);
eofflag = 0;
if ((error = VNOP_OPEN(vp, FREAD, ctx))) {
goto outsc;
} else {
open_flag = 1;
}
/*
* First pass checks if all files are appleDouble files.
*/
do {
siz = UIO_BUFF_SIZE;
uio_reset(auio, uio_offset(auio), UIO_SYSSPACE, UIO_READ);
uio_addiov(auio, CAST_USER_ADDR_T(rbuf), UIO_BUFF_SIZE);
if ((error = VNOP_READDIR(vp, auio, 0, &eofflag, &nentries, ctx))) {
goto outsc;
}
if (uio_resid(auio) != 0) {
siz -= uio_resid(auio);
}
/*
* Iterate through directory
*/
dir_pos = (void*) rbuf;
dir_end = (void*) (rbuf + siz);
dp = (struct dirent*) (dir_pos);
if (dir_pos == dir_end) {
eofflag = 1;
}
while (dir_pos < dir_end) {
/*
* Check for . and .. as well as directories
*/
if (dp->d_ino != 0 &&
!((dp->d_namlen == 1 && dp->d_name[0] == '.') ||
(dp->d_namlen == 2 && dp->d_name[0] == '.' && dp->d_name[1] == '.'))) {
/*
* Check for irregular files and ._ files
* If there is a ._._ file abort the op
*/
if (dp->d_namlen < 2 ||
strncmp(dp->d_name, "._", 2) ||
(dp->d_namlen >= 4 && !strncmp(&(dp->d_name[2]), "._", 2))) {
error = ENOTEMPTY;
goto outsc;
}
}
dir_pos = (void*) ((uint8_t*)dir_pos + dp->d_reclen);
dp = (struct dirent*)dir_pos;
}
/*
* workaround for HFS/NFS setting eofflag before end of file
*/
if (vp->v_tag == VT_HFS && nentries > 2) {
eofflag = 0;
}
if (vp->v_tag == VT_NFS) {
if (eofflag && !full_erase_flag) {
full_erase_flag = 1;
eofflag = 0;
uio_reset(auio, 0, UIO_SYSSPACE, UIO_READ);
} else if (!eofflag && full_erase_flag) {
full_erase_flag = 0;
}
}
} while (!eofflag);
/*
* If we've made it here all the files in the dir are ._ files.
* We can delete the files even though the node is suspended
* because we are the owner of the file.
*/
uio_reset(auio, 0, UIO_SYSSPACE, UIO_READ);
eofflag = 0;
full_erase_flag = 0;
do {
siz = UIO_BUFF_SIZE;
uio_reset(auio, uio_offset(auio), UIO_SYSSPACE, UIO_READ);
uio_addiov(auio, CAST_USER_ADDR_T(rbuf), UIO_BUFF_SIZE);
error = VNOP_READDIR(vp, auio, 0, &eofflag, &nentries, ctx);
if (error != 0) {
goto outsc;
}
if (uio_resid(auio) != 0) {
siz -= uio_resid(auio);
}
/*
* Iterate through directory
*/
dir_pos = (void*) rbuf;
dir_end = (void*) (rbuf + siz);
dp = (struct dirent*) dir_pos;
if (dir_pos == dir_end) {
eofflag = 1;
}
while (dir_pos < dir_end) {
/*
* Check for . and .. as well as directories
*/
if (dp->d_ino != 0 &&
!((dp->d_namlen == 1 && dp->d_name[0] == '.') ||
(dp->d_namlen == 2 && dp->d_name[0] == '.' && dp->d_name[1] == '.'))
) {
error = unlink1(ctx, vp,
CAST_USER_ADDR_T(dp->d_name), UIO_SYSSPACE,
VNODE_REMOVE_SKIP_NAMESPACE_EVENT |
VNODE_REMOVE_NO_AUDIT_PATH);
if (error && error != ENOENT) {
goto outsc;
}
}
dir_pos = (void*) ((uint8_t*)dir_pos + dp->d_reclen);
dp = (struct dirent*)dir_pos;
}
/*
* workaround for HFS/NFS setting eofflag before end of file
*/
if (vp->v_tag == VT_HFS && nentries > 2) {
eofflag = 0;
}
if (vp->v_tag == VT_NFS) {
if (eofflag && !full_erase_flag) {
full_erase_flag = 1;
eofflag = 0;
uio_reset(auio, 0, UIO_SYSSPACE, UIO_READ);
} else if (!eofflag && full_erase_flag) {
full_erase_flag = 0;
}
}
} while (!eofflag);
error = 0;
outsc:
if (open_flag) {
VNOP_CLOSE(vp, FREAD, ctx);
}
if (auio) {
uio_free(auio);
}
kfree_data(rbuf, alloc_size);
if (saved_nodatalessfaults == false) {
ut->uu_flag &= ~UT_NSPACE_NODATALESSFAULTS;
}
vnode_resume(vp);
return error;
}
void
lock_vnode_and_post(vnode_t vp, int kevent_num)
{
/* Only take the lock if there's something there! */
if (vp->v_knotes.slh_first != NULL) {
vnode_lock(vp);
KNOTE(&vp->v_knotes, kevent_num);
vnode_unlock(vp);
}
}
void panic_print_vnodes(void);
/* define PANIC_PRINTS_VNODES only if investigation is required. */
#ifdef PANIC_PRINTS_VNODES
static const char *
__vtype(uint16_t vtype)
{
switch (vtype) {
case VREG:
return "R";
case VDIR:
return "D";
case VBLK:
return "B";
case VCHR:
return "C";
case VLNK:
return "L";
case VSOCK:
return "S";
case VFIFO:
return "F";
case VBAD:
return "x";
case VSTR:
return "T";
case VCPLX:
return "X";
default:
return "?";
}
}
/*
* build a path from the bottom up
* NOTE: called from the panic path - no alloc'ing of memory and no locks!
*/
static char *
__vpath(vnode_t vp, char *str, int len, int depth)
{
int vnm_len;
const char *src;
char *dst;
if (len <= 0) {
return str;
}
/* str + len is the start of the string we created */
if (!vp->v_name) {
return str + len;
}
/* follow mount vnodes to get the full path */
if ((vp->v_flag & VROOT)) {
if (vp->v_mount != NULL && vp->v_mount->mnt_vnodecovered) {
return __vpath(vp->v_mount->mnt_vnodecovered,
str, len, depth + 1);
}
return str + len;
}
src = vp->v_name;
vnm_len = strlen(src);
if (vnm_len > len) {
/* truncate the name to fit in the string */
src += (vnm_len - len);
vnm_len = len;
}
/* start from the back and copy just characters (no NULLs) */
/* this will chop off leaf path (file) names */
if (depth > 0) {
dst = str + len - vnm_len;
memcpy(dst, src, vnm_len);
len -= vnm_len;
} else {
dst = str + len;
}
if (vp->v_parent && len > 1) {
/* follow parents up the chain */
len--;
*(dst - 1) = '/';
return __vpath(vp->v_parent, str, len, depth + 1);
}
return dst;
}
#define SANE_VNODE_PRINT_LIMIT 5000
void
panic_print_vnodes(void)
{
mount_t mnt;
vnode_t vp;
int nvnodes = 0;
const char *type;
char *nm;
char vname[257];
paniclog_append_noflush("\n***** VNODES *****\n"
"TYPE UREF ICNT PATH\n");
/* NULL-terminate the path name */
vname[sizeof(vname) - 1] = '\0';
/*
* iterate all vnodelist items in all mounts (mntlist) -> mnt_vnodelist
*/
TAILQ_FOREACH(mnt, &mountlist, mnt_list) {
if (!ml_validate_nofault((vm_offset_t)mnt, sizeof(mount_t))) {
paniclog_append_noflush("Unable to iterate the mount list %p - encountered an invalid mount pointer %p \n",
&mountlist, mnt);
break;
}
TAILQ_FOREACH(vp, &mnt->mnt_vnodelist, v_mntvnodes) {
if (!ml_validate_nofault((vm_offset_t)vp, sizeof(vnode_t))) {
paniclog_append_noflush("Unable to iterate the vnode list %p - encountered an invalid vnode pointer %p \n",
&mnt->mnt_vnodelist, vp);
break;
}
if (++nvnodes > SANE_VNODE_PRINT_LIMIT) {
return;
}
type = __vtype(vp->v_type);
nm = __vpath(vp, vname, sizeof(vname) - 1, 0);
paniclog_append_noflush("%s %0d %0d %s\n",
type, vp->v_usecount, vp->v_iocount, nm);
}
}
}
#else /* !PANIC_PRINTS_VNODES */
void
panic_print_vnodes(void)
{
return;
}
#endif
#ifdef CONFIG_IOCOUNT_TRACE
static void
record_iocount_trace_vnode(vnode_t vp, int type)
{
void *stacks[IOCOUNT_TRACE_MAX_FRAMES] = {0};
int idx = vp->v_iocount_trace[type].idx;
if (idx >= IOCOUNT_TRACE_MAX_IDX) {
return;
}
OSBacktrace((void **)&stacks[0], IOCOUNT_TRACE_MAX_FRAMES);
/*
* To save index space, only store the unique backtraces. If dup is found,
* just bump the count and return.
*/
for (int i = 0; i < idx; i++) {
if (memcmp(&stacks[0], &vp->v_iocount_trace[type].stacks[i][0],
sizeof(stacks)) == 0) {
vp->v_iocount_trace[type].counts[i]++;
return;
}
}
memcpy(&vp->v_iocount_trace[type].stacks[idx][0], &stacks[0],
sizeof(stacks));
vp->v_iocount_trace[type].counts[idx] = 1;
vp->v_iocount_trace[type].idx++;
}
static void
record_iocount_trace_uthread(vnode_t vp, int count)
{
struct uthread *ut;
ut = current_uthread();
ut->uu_iocount += count;
if (count == 1) {
if (ut->uu_vpindex < 32) {
OSBacktrace((void **)&ut->uu_pcs[ut->uu_vpindex][0], 10);
ut->uu_vps[ut->uu_vpindex] = vp;
ut->uu_vpindex++;
}
}
}
static void
record_vp(vnode_t vp, int count)
{
if (__probable(bootarg_vnode_iocount_trace == 0 &&
bootarg_uthread_iocount_trace == 0)) {
return;
}
#if CONFIG_TRIGGERS
if (vp->v_resolve) {
return;
}
#endif
if ((vp->v_flag & VSYSTEM)) {
return;
}
if (bootarg_vnode_iocount_trace) {
record_iocount_trace_vnode(vp,
(count > 0) ? IOCOUNT_TRACE_VGET : IOCOUNT_TRACE_VPUT);
}
if (bootarg_uthread_iocount_trace) {
record_iocount_trace_uthread(vp, count);
}
}
#endif /* CONFIG_IOCOUNT_TRACE */
#if CONFIG_TRIGGERS
#define __triggers_unused
#else
#define __triggers_unused __unused
#endif
resolver_result_t
vfs_resolver_result(__triggers_unused uint32_t seq, __triggers_unused enum resolver_status stat, __triggers_unused int aux)
{
#if CONFIG_TRIGGERS
/*
* |<--- 32 --->|<--- 28 --->|<- 4 ->|
* sequence auxiliary status
*/
return (((uint64_t)seq) << 32) |
(((uint64_t)(aux & 0x0fffffff)) << 4) |
(uint64_t)(stat & 0x0000000F);
#else
return (0x0ULL) | (((uint64_t)ENOTSUP) << 4) | (((uint64_t)RESOLVER_ERROR) & 0xF);
#endif
}
#if CONFIG_TRIGGERS
#define TRIG_DEBUG 0
#if TRIG_DEBUG
#define TRIG_LOG(...) do { printf("%s: ", __FUNCTION__); printf(__VA_ARGS__); } while (0)
#else
#define TRIG_LOG(...)
#endif
/*
* Resolver result functions
*/
enum resolver_status
vfs_resolver_status(resolver_result_t result)
{
/* lower 4 bits is status */
return result & 0x0000000F;
}
uint32_t
vfs_resolver_sequence(resolver_result_t result)
{
/* upper 32 bits is sequence */
return (uint32_t)(result >> 32);
}
int
vfs_resolver_auxiliary(resolver_result_t result)
{
/* 28 bits of auxiliary */
return (int)(((uint32_t)(result & 0xFFFFFFF0)) >> 4);
}
/*
* SPI
* Call in for resolvers to update vnode trigger state
*/
int
vnode_trigger_update(vnode_t vp, resolver_result_t result)
{
vnode_resolve_t rp;
uint32_t seq;
enum resolver_status stat;
if (vp->v_resolve == NULL) {
return EINVAL;
}
stat = vfs_resolver_status(result);
seq = vfs_resolver_sequence(result);
if ((stat != RESOLVER_RESOLVED) && (stat != RESOLVER_UNRESOLVED)) {
return EINVAL;
}
rp = vp->v_resolve;
lck_mtx_lock(&rp->vr_lock);
if (seq > rp->vr_lastseq) {
if (stat == RESOLVER_RESOLVED) {
rp->vr_flags |= VNT_RESOLVED;
} else {
rp->vr_flags &= ~VNT_RESOLVED;
}
rp->vr_lastseq = seq;
}
lck_mtx_unlock(&rp->vr_lock);
return 0;
}
static int
vnode_resolver_attach(vnode_t vp, vnode_resolve_t rp, boolean_t ref)
{
int error;
vnode_lock_spin(vp);
if (vp->v_resolve != NULL) {
vnode_unlock(vp);
return EINVAL;
} else {
vp->v_resolve = rp;
}
vnode_unlock(vp);
if (ref) {
error = vnode_ref_ext(vp, O_EVTONLY, VNODE_REF_FORCE);
if (error != 0) {
panic("VNODE_REF_FORCE didn't help...");
}
}
return 0;
}
/*
* VFS internal interfaces for vnode triggers
*
* vnode must already have an io count on entry
* v_resolve is stable when io count is non-zero
*/
static int
vnode_resolver_create(mount_t mp, vnode_t vp, struct vnode_trigger_param *tinfo, boolean_t external)
{
vnode_resolve_t rp;
int result;
char byte;
#if 1
/* minimum pointer test (debugging) */
if (tinfo->vnt_data) {
byte = *((char *)tinfo->vnt_data);
}
#endif
rp = kalloc_type(struct vnode_resolve, Z_WAITOK | Z_NOFAIL);
lck_mtx_init(&rp->vr_lock, &trigger_vnode_lck_grp, &trigger_vnode_lck_attr);
rp->vr_resolve_func = tinfo->vnt_resolve_func;
rp->vr_unresolve_func = tinfo->vnt_unresolve_func;
rp->vr_rearm_func = tinfo->vnt_rearm_func;
rp->vr_reclaim_func = tinfo->vnt_reclaim_func;
rp->vr_data = tinfo->vnt_data;
rp->vr_lastseq = 0;
rp->vr_flags = tinfo->vnt_flags & VNT_VALID_MASK;
if (external) {
rp->vr_flags |= VNT_EXTERNAL;
}
result = vnode_resolver_attach(vp, rp, external);
if (result != 0) {
goto out;
}
if (mp) {
OSAddAtomic(1, &mp->mnt_numtriggers);
}
return result;
out:
kfree_type(struct vnode_resolve, rp);
return result;
}
static void
vnode_resolver_release(vnode_resolve_t rp)
{
/*
* Give them a chance to free any private data
*/
if (rp->vr_data && rp->vr_reclaim_func) {
rp->vr_reclaim_func(NULLVP, rp->vr_data);
}
lck_mtx_destroy(&rp->vr_lock, &trigger_vnode_lck_grp);
kfree_type(struct vnode_resolve, rp);
}
/* Called after the vnode has been drained */
static void
vnode_resolver_detach(vnode_t vp)
{
vnode_resolve_t rp;
mount_t mp;
mp = vnode_mount(vp);
vnode_lock(vp);
rp = vp->v_resolve;
vp->v_resolve = NULL;
vnode_unlock(vp);
if ((rp->vr_flags & VNT_EXTERNAL) != 0) {
vnode_rele_ext(vp, O_EVTONLY, 1);
}
vnode_resolver_release(rp);
/* Keep count of active trigger vnodes per mount */
OSAddAtomic(-1, &mp->mnt_numtriggers);
}
__private_extern__
void
vnode_trigger_rearm(vnode_t vp, vfs_context_t ctx)
{
vnode_resolve_t rp;
resolver_result_t result;
enum resolver_status status;
uint32_t seq;
if ((vp->v_resolve == NULL) ||
(vp->v_resolve->vr_rearm_func == NULL) ||
(vp->v_resolve->vr_flags & VNT_AUTO_REARM) == 0) {
return;
}
rp = vp->v_resolve;
lck_mtx_lock(&rp->vr_lock);
/*
* Check if VFS initiated this unmount. If so, we'll catch it after the unresolve completes.
*/
if (rp->vr_flags & VNT_VFS_UNMOUNTED) {
lck_mtx_unlock(&rp->vr_lock);
return;
}
/* Check if this vnode is already armed */
if ((rp->vr_flags & VNT_RESOLVED) == 0) {
lck_mtx_unlock(&rp->vr_lock);
return;
}
lck_mtx_unlock(&rp->vr_lock);
result = rp->vr_rearm_func(vp, 0, rp->vr_data, ctx);
status = vfs_resolver_status(result);
seq = vfs_resolver_sequence(result);
lck_mtx_lock(&rp->vr_lock);
if (seq > rp->vr_lastseq) {
if (status == RESOLVER_UNRESOLVED) {
rp->vr_flags &= ~VNT_RESOLVED;
}
rp->vr_lastseq = seq;
}
lck_mtx_unlock(&rp->vr_lock);
}
__private_extern__
int
vnode_trigger_resolve(vnode_t vp, struct nameidata *ndp, vfs_context_t ctx)
{
vnode_resolve_t rp;
enum path_operation op;
resolver_result_t result;
enum resolver_status status;
uint32_t seq;
/*
* N.B. we cannot call vfs_context_can_resolve_triggers()
* here because we really only want to suppress that in
* the event the trigger will be resolved by something in
* user-space. Any triggers that are resolved by the kernel
* do not pose a threat of deadlock.
*/
/* Only trigger on topmost vnodes */
if ((vp->v_resolve == NULL) ||
(vp->v_resolve->vr_resolve_func == NULL) ||
(vp->v_mountedhere != NULL)) {
return 0;
}
rp = vp->v_resolve;
lck_mtx_lock(&rp->vr_lock);
/* Check if this vnode is already resolved */
if (rp->vr_flags & VNT_RESOLVED) {
lck_mtx_unlock(&rp->vr_lock);
return 0;
}
lck_mtx_unlock(&rp->vr_lock);
#if CONFIG_MACF
if ((rp->vr_flags & VNT_KERN_RESOLVE) == 0) {
/*
* VNT_KERN_RESOLVE indicates this trigger has no parameters
* at the discression of the accessing process other than
* the act of access. All other triggers must be checked
*/
int rv = mac_vnode_check_trigger_resolve(ctx, vp, &ndp->ni_cnd);
if (rv != 0) {
return rv;
}
}
#endif
/*
* XXX
* assumes that resolver will not access this trigger vnode (otherwise the kernel will deadlock)
* is there anyway to know this???
* there can also be other legitimate lookups in parallel
*
* XXX - should we call this on a separate thread with a timeout?
*
* XXX - should we use ISLASTCN to pick the op value??? Perhaps only leafs should
* get the richer set and non-leafs should get generic OP_LOOKUP? TBD
*/
op = (ndp->ni_op < OP_MAXOP) ? ndp->ni_op: OP_LOOKUP;
result = rp->vr_resolve_func(vp, &ndp->ni_cnd, op, 0, rp->vr_data, ctx);
status = vfs_resolver_status(result);
seq = vfs_resolver_sequence(result);
lck_mtx_lock(&rp->vr_lock);
if (seq > rp->vr_lastseq) {
if (status == RESOLVER_RESOLVED) {
rp->vr_flags |= VNT_RESOLVED;
}
rp->vr_lastseq = seq;
}
lck_mtx_unlock(&rp->vr_lock);
/* On resolver errors, propagate the error back up */
return status == RESOLVER_ERROR ? vfs_resolver_auxiliary(result) : 0;
}
static int
vnode_trigger_unresolve(vnode_t vp, int flags, vfs_context_t ctx)
{
vnode_resolve_t rp;
resolver_result_t result;
enum resolver_status status;
uint32_t seq;
if ((vp->v_resolve == NULL) || (vp->v_resolve->vr_unresolve_func == NULL)) {
return 0;
}
rp = vp->v_resolve;
lck_mtx_lock(&rp->vr_lock);
/* Check if this vnode is already resolved */
if ((rp->vr_flags & VNT_RESOLVED) == 0) {
printf("vnode_trigger_unresolve: not currently resolved\n");
lck_mtx_unlock(&rp->vr_lock);
return 0;
}
rp->vr_flags |= VNT_VFS_UNMOUNTED;
lck_mtx_unlock(&rp->vr_lock);
/*
* XXX
* assumes that resolver will not access this trigger vnode (otherwise the kernel will deadlock)
* there can also be other legitimate lookups in parallel
*
* XXX - should we call this on a separate thread with a timeout?
*/
result = rp->vr_unresolve_func(vp, flags, rp->vr_data, ctx);
status = vfs_resolver_status(result);
seq = vfs_resolver_sequence(result);
lck_mtx_lock(&rp->vr_lock);
if (seq > rp->vr_lastseq) {
if (status == RESOLVER_UNRESOLVED) {
rp->vr_flags &= ~VNT_RESOLVED;
}
rp->vr_lastseq = seq;
}
rp->vr_flags &= ~VNT_VFS_UNMOUNTED;
lck_mtx_unlock(&rp->vr_lock);
/* On resolver errors, propagate the error back up */
return status == RESOLVER_ERROR ? vfs_resolver_auxiliary(result) : 0;
}
static int
triggerisdescendant(mount_t mp, mount_t rmp)
{
int match = FALSE;
/*
* walk up vnode covered chain looking for a match
*/
name_cache_lock_shared();
while (1) {
vnode_t vp;
/* did we encounter "/" ? */
if (mp->mnt_flag & MNT_ROOTFS) {
break;
}
vp = mp->mnt_vnodecovered;
if (vp == NULLVP) {
break;
}
mp = vp->v_mount;
if (mp == rmp) {
match = TRUE;
break;
}
}
name_cache_unlock();
return match;
}
struct trigger_unmount_info {
vfs_context_t ctx;
mount_t top_mp;
vnode_t trigger_vp;
mount_t trigger_mp;
uint32_t trigger_vid;
int flags;
};
static int
trigger_unmount_callback(mount_t mp, void * arg)
{
struct trigger_unmount_info * infop = (struct trigger_unmount_info *)arg;
boolean_t mountedtrigger = FALSE;
/*
* When we encounter the top level mount we're done
*/
if (mp == infop->top_mp) {
return VFS_RETURNED_DONE;
}
if ((mp->mnt_vnodecovered == NULL) ||
(vnode_getwithref(mp->mnt_vnodecovered) != 0)) {
return VFS_RETURNED;
}
if ((mp->mnt_vnodecovered->v_mountedhere == mp) &&
(mp->mnt_vnodecovered->v_resolve != NULL) &&
(mp->mnt_vnodecovered->v_resolve->vr_flags & VNT_RESOLVED)) {
mountedtrigger = TRUE;
}
vnode_put(mp->mnt_vnodecovered);
/*
* When we encounter a mounted trigger, check if its under the top level mount
*/
if (!mountedtrigger || !triggerisdescendant(mp, infop->top_mp)) {
return VFS_RETURNED;
}
/*
* Process any pending nested mount (now that its not referenced)
*/
if ((infop->trigger_vp != NULLVP) &&
(vnode_getwithvid(infop->trigger_vp, infop->trigger_vid) == 0)) {
vnode_t vp = infop->trigger_vp;
int error;
vnode_drop(infop->trigger_vp);
infop->trigger_vp = NULLVP;
if (mp == vp->v_mountedhere) {
vnode_put(vp);
printf("trigger_unmount_callback: unexpected match '%s'\n",
mp->mnt_vfsstat.f_mntonname);
return VFS_RETURNED;
}
if (infop->trigger_mp != vp->v_mountedhere) {
vnode_put(vp);
printf("trigger_unmount_callback: trigger mnt changed! (%p != %p)\n",
infop->trigger_mp, vp->v_mountedhere);
goto savenext;
}
error = vnode_trigger_unresolve(vp, infop->flags, infop->ctx);
vnode_put(vp);
if (error) {
printf("unresolving: '%s', err %d\n",
vp->v_mountedhere ? vp->v_mountedhere->mnt_vfsstat.f_mntonname :
"???", error);
return VFS_RETURNED_DONE; /* stop iteration on errors */
}
} else if (infop->trigger_vp != NULLVP) {
vnode_drop(infop->trigger_vp);
}
savenext:
/*
* We can't call resolver here since we hold a mount iter
* ref on mp so save its covered vp for later processing
*/
infop->trigger_vp = mp->mnt_vnodecovered;
if ((infop->trigger_vp != NULLVP) &&
(vnode_getwithref(infop->trigger_vp) == 0)) {
if (infop->trigger_vp->v_mountedhere == mp) {
infop->trigger_vid = infop->trigger_vp->v_id;
vnode_hold(infop->trigger_vp);
infop->trigger_mp = mp;
}
vnode_put(infop->trigger_vp);
}
return VFS_RETURNED;
}
/*
* Attempt to unmount any trigger mounts nested underneath a mount.
* This is a best effort attempt and no retries are performed here.
*
* Note: mp->mnt_rwlock is held exclusively on entry (so be carefull)
*/
__private_extern__
void
vfs_nested_trigger_unmounts(mount_t mp, int flags, vfs_context_t ctx)
{
struct trigger_unmount_info info;
/* Must have trigger vnodes */
if (mp->mnt_numtriggers == 0) {
return;
}
/* Avoid recursive requests (by checking covered vnode) */
if ((mp->mnt_vnodecovered != NULL) &&
(vnode_getwithref(mp->mnt_vnodecovered) == 0)) {
boolean_t recursive = FALSE;
if ((mp->mnt_vnodecovered->v_mountedhere == mp) &&
(mp->mnt_vnodecovered->v_resolve != NULL) &&
(mp->mnt_vnodecovered->v_resolve->vr_flags & VNT_VFS_UNMOUNTED)) {
recursive = TRUE;
}
vnode_put(mp->mnt_vnodecovered);
if (recursive) {
return;
}
}
/*
* Attempt to unmount any nested trigger mounts (best effort)
*/
info.ctx = ctx;
info.top_mp = mp;
info.trigger_vp = NULLVP;
info.trigger_vid = 0;
info.trigger_mp = NULL;
info.flags = flags;
(void) vfs_iterate(VFS_ITERATE_TAIL_FIRST, trigger_unmount_callback, &info);
/*
* Process remaining nested mount (now that its not referenced)
*/
if ((info.trigger_vp != NULLVP) &&
(vnode_getwithvid(info.trigger_vp, info.trigger_vid) == 0)) {
vnode_t vp = info.trigger_vp;
if (info.trigger_mp == vp->v_mountedhere) {
(void) vnode_trigger_unresolve(vp, flags, ctx);
}
vnode_put(vp);
vnode_drop(vp);
} else if (info.trigger_vp != NULLVP) {
vnode_drop(info.trigger_vp);
}
}
int
vfs_addtrigger(mount_t mp, const char *relpath, struct vnode_trigger_info *vtip, vfs_context_t ctx)
{
struct nameidata *ndp;
int res;
vnode_t rvp, vp;
struct vnode_trigger_param vtp;
/*
* Must be called for trigger callback, wherein rwlock is held
*/
lck_rw_assert(&mp->mnt_rwlock, LCK_RW_ASSERT_HELD);
TRIG_LOG("Adding trigger at %s\n", relpath);
TRIG_LOG("Trying VFS_ROOT\n");
ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_NOFAIL);
/*
* We do a lookup starting at the root of the mountpoint, unwilling
* to cross into other mountpoints.
*/
res = VFS_ROOT(mp, &rvp, ctx);
if (res != 0) {
goto out;
}
TRIG_LOG("Trying namei\n");
NDINIT(ndp, LOOKUP, OP_LOOKUP, USEDVP | NOCROSSMOUNT | FOLLOW, UIO_SYSSPACE,
CAST_USER_ADDR_T(relpath), ctx);
ndp->ni_dvp = rvp;
res = namei(ndp);
if (res != 0) {
vnode_put(rvp);
goto out;
}
vp = ndp->ni_vp;
nameidone(ndp);
vnode_put(rvp);
TRIG_LOG("Trying vnode_resolver_create()\n");
/*
* Set up blob. vnode_create() takes a larger structure
* with creation info, and we needed something different
* for this case. One needs to win, or we need to munge both;
* vnode_create() wins.
*/
bzero(&vtp, sizeof(vtp));
vtp.vnt_resolve_func = vtip->vti_resolve_func;
vtp.vnt_unresolve_func = vtip->vti_unresolve_func;
vtp.vnt_rearm_func = vtip->vti_rearm_func;
vtp.vnt_reclaim_func = vtip->vti_reclaim_func;
vtp.vnt_reclaim_func = vtip->vti_reclaim_func;
vtp.vnt_data = vtip->vti_data;
vtp.vnt_flags = vtip->vti_flags;
res = vnode_resolver_create(mp, vp, &vtp, TRUE);
vnode_put(vp);
out:
kfree_type(struct nameidata, ndp);
TRIG_LOG("Returning %d\n", res);
return res;
}
#endif /* CONFIG_TRIGGERS */
vm_offset_t
kdebug_vnode(vnode_t vp)
{
return VM_KERNEL_ADDRPERM(vp);
}
static int flush_cache_on_write = 0;
SYSCTL_INT(_kern, OID_AUTO, flush_cache_on_write,
CTLFLAG_RW | CTLFLAG_LOCKED, &flush_cache_on_write, 0,
"always flush the drive cache on writes to uncached files");
int
vnode_should_flush_after_write(vnode_t vp, int ioflag)
{
return flush_cache_on_write
&& (ISSET(ioflag, IO_NOCACHE) || vnode_isnocache(vp));
}
/*
* sysctl for use by disk I/O tracing tools to get the list of existing
* vnodes' paths
*/
#define NPATH_WORDS (MAXPATHLEN / sizeof(unsigned long))
struct vnode_trace_paths_context {
uint64_t count;
/*
* Must be a multiple of 4, then -1, for tracing!
*/
unsigned long path[NPATH_WORDS + (4 - (NPATH_WORDS % 4)) - 1];
};
static int
vnode_trace_path_callback(struct vnode *vp, void *vctx)
{
struct vnode_trace_paths_context *ctx = vctx;
size_t path_len = sizeof(ctx->path);
int getpath_len = (int)path_len;
if (vn_getpath(vp, (char *)ctx->path, &getpath_len) == 0) {
/* vn_getpath() NUL-terminates, and len includes the NUL. */
assert(getpath_len >= 0);
path_len = (size_t)getpath_len;
assert(path_len <= sizeof(ctx->path));
kdebug_vfs_lookup(ctx->path, (int)path_len, vp,
KDBG_VFS_LOOKUP_FLAG_LOOKUP | KDBG_VFS_LOOKUP_FLAG_NOPROCFILT);
if (++(ctx->count) == 1000) {
thread_yield_to_preemption();
ctx->count = 0;
}
}
return VNODE_RETURNED;
}
static int
vfs_trace_paths_callback(mount_t mp, void *arg)
{
if (mp->mnt_flag & MNT_LOCAL) {
vnode_iterate(mp, VNODE_ITERATE_ALL, vnode_trace_path_callback, arg);
}
return VFS_RETURNED;
}
static int sysctl_vfs_trace_paths SYSCTL_HANDLER_ARGS {
struct vnode_trace_paths_context ctx;
(void)oidp;
(void)arg1;
(void)arg2;
(void)req;
if (!kauth_cred_issuser(kauth_cred_get())) {
return EPERM;
}
if (!kdebug_enable || !kdebug_debugid_enabled(VFS_LOOKUP)) {
return EINVAL;
}
bzero(&ctx, sizeof(struct vnode_trace_paths_context));
vfs_iterate(0, vfs_trace_paths_callback, &ctx);
return 0;
}
SYSCTL_PROC(_vfs_generic, OID_AUTO, trace_paths, CTLFLAG_RD | CTLFLAG_LOCKED | CTLFLAG_MASKED, NULL, 0, &sysctl_vfs_trace_paths, "-", "trace_paths");
#if CONFIG_FILE_LEASES
#include <IOKit/IOBSD.h>
#include <sys/file_internal.h>
#define FILE_LEASES_ENTITLEMENT "com.apple.private.vfs.file-leases"
static uint32_t lease_break_timeout = 60; /* secs */
#if (DEVELOPMENT || DEBUG)
static int lease_debug = 0;
static int lease_entitlement_override = 0;
SYSCTL_NODE(_vfs, OID_AUTO, lease, CTLFLAG_RW | CTLFLAG_LOCKED, NULL, "vfs lease");
SYSCTL_UINT(_vfs_lease, OID_AUTO, break_timeout, CTLFLAG_RW | CTLFLAG_LOCKED, &lease_break_timeout, 0, "");
SYSCTL_INT(_vfs_lease, OID_AUTO, debug, CTLFLAG_RW | CTLFLAG_LOCKED, &lease_debug, 0, "");
SYSCTL_INT(_vfs_lease, OID_AUTO, entitlement_override, CTLFLAG_RW | CTLFLAG_LOCKED, &lease_entitlement_override, 0, "");
#define LEASEDBG(fmt, args...) \
do { \
if (__improbable(lease_debug)) { \
pid_t cur_pid = proc_getpid(current_proc()); \
printf("%s(%d): " fmt "\n", __func__, cur_pid, ##args); \
} \
} while(0)
#else
#define LEASEDBG(fmt, args...) /**/
#endif /* (DEVELOPMENT || DEBUG) */
static bool
allow_setlease(vfs_context_t ctx)
{
bool entitled;
entitled = IOTaskHasEntitlement(vfs_context_task(ctx),
FILE_LEASES_ENTITLEMENT);
#if (DEVELOPMENT || DEBUG)
if (!entitled) {
entitled = (lease_entitlement_override == 1);
}
#endif
return entitled;
}
static file_lease_t
file_lease_alloc(struct fileglob *fg, int fl_type, pid_t pid)
{
file_lease_t fl;
fl = kalloc_type(struct file_lease, Z_WAITOK);
/*
* Duplicated file descriptors created by dup() or fork() would have the
* same 'fileglob' so the lease can be released or modified with the
* duplicated fds. Opening the same file (by either same or different
* process) would have different 'fileglob' so a lease always follows a
* 'fileglob'.
*/
fl->fl_fg = fg;
fl->fl_type = fl_type;
fl->fl_pid = pid;
fl->fl_downgrade_start = fl->fl_release_start = 0;
return fl;
}
static void
file_lease_free(file_lease_t fl)
{
kfree_type(struct file_lease, fl);
}
/*
* A read lease can be placed only on a file/directory that is opened for
* read-only which means no other processes have the file/directory opened in
* read-write/write-only mode or mmap'ed writable.
* A write lease can be placed on a file only if there are no other opens
* for the file.
*
* Needs to be called with vnode's lock held.
*/
static int
check_for_open_conflict(vnode_t vp, struct fileglob *fg, int fl_type,
int expcounts)
{
int error = 0;
if (fl_type == F_RDLCK) {
if (vp->v_writecount > expcounts &&
!(vp->v_writecount == 1 && (fg->fg_flag & FWRITE))) {
error = EAGAIN;
} else if (ubc_is_mapped_writable(vp)) {
error = EAGAIN;
}
} else if (fl_type == F_WRLCK && vp->v_usecount > expcounts) {
error = EAGAIN;
}
return error;
}
/* Needs to be called with vnode's lock held. */
static void
modify_file_lease(vnode_t vp, file_lease_t fl, int new_fl_type,
struct fileglob *new_fg)
{
LEASEDBG("fl %p changing fl_type from %d to %d (flags 0x%x)",
fl, fl->fl_type, new_fl_type, fl->fl_flags);
fl->fl_type = new_fl_type;
/*
* The lease being modified may be using a different file
* descriptor, so usurp the fileglob pointer here. In this
* case the old descriptor no longer holds the lease.
*/
if (new_fg != NULL) {
fl->fl_fg = new_fg;
}
if (fl->fl_flags & FL_FLAG_RELEASE_PENDING ||
fl->fl_flags & FL_FLAG_DOWNGRADE_PENDING) {
wakeup(&vp->v_leases);
}
}
static int
acquire_file_lease(vnode_t vp, struct fileglob *fg, int fl_type, int expcounts,
vfs_context_t ctx)
{
file_lease_t fl, new_fl, our_fl;
int error;
/* Make sure "expected count" looks sane. */
if (expcounts < 0 || expcounts > OPEN_MAX) {
return EINVAL;
}
new_fl = file_lease_alloc(fg, fl_type, vfs_context_pid(ctx));
vnode_lock(vp);
error = check_for_open_conflict(vp, fg, fl_type, expcounts);
if (error) {
LEASEDBG("open conflict on vp %p type %d writecnt %d usecnt %d "
"fl_type %d expcounts %d",
vp, vp->v_type, vp->v_writecount, vp->v_usecount, fl_type,
expcounts);
goto out;
}
our_fl = NULL;
LIST_FOREACH(fl, &vp->v_leases, fl_link) {
/* Does the existing lease belong to us? */
if (fl->fl_fg == new_fl->fl_fg ||
fl->fl_pid == new_fl->fl_pid) {
our_fl = fl;
continue;
}
/*
* We don't allow placing a new write lease when there is an existing
* read lease that doesn't belong to us. We also don't allow putting
* a new read lease if there is a pending release on the lease.
* Putting a new read lease when there is a pending downgrade on the
* lease is fine as it won't cause lease conflict.
*/
if (fl_type == F_WRLCK || fl->fl_flags & FL_FLAG_RELEASE_PENDING) {
break;
}
}
/*
* Found an existing lease that we don't own and it conflicts with the
* new lease.
*/
if (fl) {
LEASEDBG("lease conflict on vp %p fl %p fl_type %d cur_fl_type %d",
vp, fl, fl_type, fl->fl_type);
goto out;
}
/* Found an existing lease that we own so just change the type. */
if (our_fl) {
LEASEDBG("replace lease on vp %p fl %p old_fl_type %d new_fl_type %d",
vp, our_fl, our_fl->fl_type, fl_type);
modify_file_lease(vp, our_fl, new_fl->fl_type, new_fl->fl_fg);
goto out;
}
LEASEDBG("acquired lease on vp %p type %d fl %p fl_type %d fg %p",
vp, vp->v_type, new_fl, new_fl->fl_type, new_fl->fl_fg);
LIST_INSERT_HEAD(&vp->v_leases, new_fl, fl_link);
new_fl = NULL;
out:
vnode_unlock(vp);
if (new_fl) {
file_lease_free(new_fl);
}
return error;
}
static int
release_file_lease(vnode_t vp, struct fileglob *fg)
{
file_lease_t fl, fl_tmp;
int error = 0;
LEASEDBG("request to release lease on vp %p type %d fg %p",
vp, vp->v_type, fg);
vnode_lock(vp);
LIST_FOREACH_SAFE(fl, &vp->v_leases, fl_link, fl_tmp) {
if (fl->fl_fg == fg) {
LEASEDBG("released lease on vp %p fl %p type %d",
vp, fl, fl->fl_type);
LIST_REMOVE(fl, fl_link);
modify_file_lease(vp, fl, F_UNLCK, NULL);
break;
}
}
vnode_unlock(vp);
if (fl) {
file_lease_free(fl);
} else {
error = ENOLCK;
}
return error;
}
/*
* Acquire or release a file lease according to the given type (F_RDLCK,
* F_WRLCK or F_UNLCK).
*
* Returns: 0 Success
* EAGAIN Failed to acquire a file lease due to conflicting opens
* ENOLCK Failed to release a file lease due to lease not found
* EPERM Current task doesn't have the entitlement
*/
int
vnode_setlease(vnode_t vp, struct fileglob *fg, int fl_type, int expcounts,
vfs_context_t ctx)
{
int error;
if (!allow_setlease(ctx)) {
return EPERM;
}
error = (fl_type == F_UNLCK) ? release_file_lease(vp, fg) :
acquire_file_lease(vp, fg, fl_type, expcounts, ctx);
return error;
}
/*
* Retrieve the currently in place lease for the file.
*
* Returns:
* F_RDLCK Read lease
* F_WRLCK Write lease
* F_UNLCK No lease
*/
int
vnode_getlease(vnode_t vp)
{
file_lease_t fl;
int fl_type = F_UNLCK;
vnode_lock(vp);
/*
* There should be only one type of lease in the list as read and write
* leases can't co-exist for the same file.
*/
fl = LIST_FIRST(&vp->v_leases);
if (fl) {
fl_type = fl->fl_type;
}
vnode_unlock(vp);
LEASEDBG("vp %p fl %p fl_type %d", vp, fl, fl_type);
return fl_type;
}
/* Must be called with vnode's lock held. */
static bool
check_for_lease_conflict(vnode_t vp, int breaker_fl_type, vfs_context_t ctx)
{
file_lease_t fl;
pid_t pid = vfs_context_pid(ctx);
bool is_conflict = false;
LIST_FOREACH(fl, &vp->v_leases, fl_link) {
if ((fl->fl_type == F_WRLCK && fl->fl_pid != pid) ||
(breaker_fl_type == F_WRLCK && fl->fl_pid != pid)) {
LEASEDBG("conflict detected on vp %p type %d fl_type %d "
"breaker_fl_type %d",
vp, vp->v_type, fl->fl_type, breaker_fl_type);
is_conflict = true;
break;
}
}
return is_conflict;
}
static uint64_t
absolutetime_elapsed_in_secs(uint64_t start)
{
uint64_t elapsed, elapsed_sec;
uint64_t now = mach_absolute_time();
elapsed = now - start;
absolutetime_to_nanoseconds(elapsed, &elapsed_sec);
elapsed_sec /= NSEC_PER_SEC;
return elapsed_sec;
}
/* Must be called with vnode's lock held. */
static void
handle_lease_break_timedout(vnode_t vp)
{
file_lease_t fl, fl_tmp;
uint64_t elapsed_sec;
LIST_FOREACH_SAFE(fl, &vp->v_leases, fl_link, fl_tmp) {
if (fl->fl_flags & FL_FLAG_DOWNGRADE_PENDING) {
elapsed_sec = absolutetime_elapsed_in_secs(fl->fl_downgrade_start);
if (elapsed_sec >= lease_break_timeout) {
LEASEDBG("force downgrade on vp %p for fl %p elapsed %llu "
"timeout %u", vp, fl, elapsed_sec, lease_break_timeout);
fl->fl_flags &= ~FL_FLAG_DOWNGRADE_PENDING;
fl->fl_downgrade_start = 0;
modify_file_lease(vp, fl, F_RDLCK, NULL);
continue;
}
}
if (fl->fl_flags & FL_FLAG_RELEASE_PENDING) {
elapsed_sec = absolutetime_elapsed_in_secs(fl->fl_release_start);
if (elapsed_sec >= lease_break_timeout) {
LEASEDBG("force release on vp %p for fl %p elapsed %llu "
"timeout %u", vp, fl, elapsed_sec, lease_break_timeout);
LIST_REMOVE(fl, fl_link);
file_lease_free(fl);
continue;
}
}
}
/* Wakeup the lease breaker(s). */
wakeup(&vp->v_leases);
}
/* Must be called with vnode's lock held. */
static void
wait_for_lease_break(vnode_t vp, int breaker_fl_type, vfs_context_t ctx)
{
file_lease_t fl;
struct timespec ts;
uint64_t elapsed_sec, start_time;
int error;
restart:
fl = LIST_FIRST(&vp->v_leases);
assert(fl);
/*
* In a rare case it is possible that the lease that we are blocked on has
* been released and a new lease has been put in place after we are
* signalled to wake up. In this particular, we would treat it as no
* conflict and proceed. This could only happen for directory leasing.
*/
if ((fl->fl_flags & (FL_FLAG_DOWNGRADE_PENDING | FL_FLAG_RELEASE_PENDING)) == 0) {
LEASEDBG("new lease in place on vp %p fl %p fl_type %d "
"breaker_fl_type %d",
vp, fl, fl->fl_type, breaker_fl_type);
return;
}
/*
* Figure out which timer to use for lease break timedout as we could have
* both timers active. If both timers active, pick the one with earliest
* start time.
*/
if (fl->fl_release_start) {
if (fl->fl_downgrade_start == 0 ||
fl->fl_downgrade_start < fl->fl_release_start) {
start_time = fl->fl_release_start;
} else {
start_time = fl->fl_downgrade_start;
}
} else {
start_time = fl->fl_downgrade_start;
}
assert(start_time > 0);
elapsed_sec = absolutetime_elapsed_in_secs(start_time);
LEASEDBG("elapsed_sec %llu release_start %llu downgrade_start %llu",
elapsed_sec, fl->fl_release_start, fl->fl_downgrade_start);
ts.tv_sec = (lease_break_timeout > elapsed_sec ?
(lease_break_timeout - elapsed_sec) : 0);
ts.tv_nsec = (ts.tv_sec == 0 ? 1 : 0);
error = msleep(&vp->v_leases, &vp->v_lock, PVFS, __func__, &ts);
if (error == 0 || error != EWOULDBLOCK) {
/*
* Woken up due to lease is released/downgraded by lease holder.
* We don't expect any other error from msleep() beside EWOULDBLOCK.
* Check if there is any further conflicts. If so, then continue to
* wait for the next conflict to resolve.
*/
if (check_for_lease_conflict(vp, breaker_fl_type, ctx)) {
goto restart;
}
} else {
/*
* Woken due to lease break timeout expired (EWOULDBLOCK returned).
* Break/downgrade all conflicting leases.
*/
handle_lease_break_timedout(vp);
if (check_for_lease_conflict(vp, breaker_fl_type, ctx)) {
goto restart;
}
}
}
/* Must be called with vnode's lock held. */
static void
send_lease_break_event(vnode_t vp, uint32_t event)
{
if (vp->v_knotes.slh_first != NULL) {
KNOTE(&vp->v_knotes, event);
}
}
static bool
is_dataless_file(vnode_t vp, vfs_context_t ctx)
{
struct vnode_attr va;
bool is_dataless = false;
int error;
VATTR_INIT(&va);
VATTR_WANTED(&va, va_flags);
error = vnode_getattr(vp, &va, ctx);
if (!error && (va.va_flags & SF_DATALESS)) {
is_dataless = true;
}
return is_dataless;
}
/*
* Break lease(s) in place for the file when there is conflict.
* This function would return 0 for almost all call sites. The only exception
* is when it is called from open1() with O_NONBLOCK flag and it needs to block
* waiting for the lease conflict(s) to resolve. In this case EWOULDBLOCK is
* returned.
*/
int
vnode_breaklease(vnode_t vp, uint32_t oflags, vfs_context_t ctx)
{
file_lease_t fl;
uint64_t now;
int fl_type;
int error = 0;
vnode_lock(vp);
if (__probable(LIST_EMPTY(&vp->v_leases))) {
goto out_unlock;
}
/* Determine the access mode requested by the lease breaker. */
fl_type = (oflags & (O_WRONLY | O_RDWR | O_CREAT | O_TRUNC)) ? F_WRLCK : F_RDLCK;
/*
* If the lease-breaker is just reading, check that it can break
* leases first. If the lease-breaker is writing, or if the
* context was not specified, we always break.
* We skip lease break if the lease-breaker is dataless manipulator and
* the file is dataless.
*/
if ((fl_type == F_RDLCK && !vfs_context_can_break_leases(ctx)) ||
(vfs_context_is_dataless_manipulator(ctx) && (vp->v_type == VREG) &&
is_dataless_file(vp, ctx))) {
goto out_unlock;
}
if (!check_for_lease_conflict(vp, fl_type, ctx)) {
goto out_unlock;
}
now = mach_absolute_time();
LEASEDBG("break lease on vp %p type %d oflags 0x%x cur_time %llu",
vp, vp->v_type, oflags, now);
/*
* We get to this point then this means all lease(s) are conflict and
* we need to send the lease break event to the lease holder(s).
* It is possible that a lease could have both downgrade and release events
* pending triggered by multiple breakers trying to open the file in
* different modes. Both events would have different lease break timers.
* Consider the following case:
* 1. Process A holds the write lease on file X.
* 2. Provess B opens the file X in read-only mode.
* This triggers downgrade lease event to Process A.
* 3. While downgrade is pending, Process C opens the file X in read-write
* mode. This triggers release lease event to Process A.
*/
LIST_FOREACH(fl, &vp->v_leases, fl_link) {
if (fl_type == F_WRLCK) {
/* File is opened for writing or truncate. */
if (fl->fl_flags & FL_FLAG_RELEASE_PENDING) {
continue;
}
fl->fl_release_start = now;
fl->fl_flags |= FL_FLAG_RELEASE_PENDING;
send_lease_break_event(vp, NOTE_LEASE_RELEASE);
} else {
/* File is opened for reading. */
if (fl->fl_flags & FL_FLAG_DOWNGRADE_PENDING ||
fl->fl_flags & FL_FLAG_RELEASE_PENDING) {
continue;
}
fl->fl_downgrade_start = now;
fl->fl_flags |= FL_FLAG_DOWNGRADE_PENDING;
send_lease_break_event(vp, NOTE_LEASE_DOWNGRADE);
}
}
/*
* If open is requested with O_NONBLOCK, then we can't block and wait for
* the lease to be released/downgraded. Just bail out with EWOULDBLOCK.
*/
if (oflags & O_NONBLOCK) {
error = EWOULDBLOCK;
goto out;
}
wait_for_lease_break(vp, fl_type, ctx);
out:
LEASEDBG("break lease on vp %p oflags 0x%x, error %d", vp, oflags, error);
out_unlock:
vnode_unlock(vp);
return error;
}
/*
* Get parent vnode by parent ID (only for file system that supports
* MNTK_PATH_FROM_ID).
* On success, the parent's vnode is returned with iocount held.
*/
static vnode_t
vnode_getparent_byid(vnode_t vp)
{
struct vnode_attr va;
vnode_t dvp = NULLVP;
vfs_context_t ctx = vfs_context_current();
int error;
if (!(vp->v_mount->mnt_kern_flag & MNTK_PATH_FROM_ID)) {
goto out;
}
VATTR_INIT(&va);
VATTR_WANTED(&va, va_parentid);
/* Get the vnode's parent id from the file system. */
error = vnode_getattr(vp, &va, ctx);
if (error || !VATTR_IS_SUPPORTED(&va, va_parentid)) {
goto out;
}
/*
* Ask the file system for the parent vnode.
* We are ignoring the error here as we don't expect the parent vnode to be
* populated on error.
*/
(void)VFS_VGET(vp->v_mount, (ino64_t)va.va_parentid, &dvp, ctx);
out:
return dvp;
}
/*
* Break directory's lease.
* If 'need_parent' is true, then parent is obtained via vnode_getparent() (or
* vnode_getparent_byid()) on the provided 'vp'.
*/
void
vnode_breakdirlease(vnode_t vp, bool need_parent, uint32_t oflags)
{
vnode_t dvp;
if ((vnode_vtype(vp) != VREG && vnode_vtype(vp) != VDIR) ||
(vp == rootvnode)) {
return;
}
/*
* If parent is not provided, first try to get it from the name cache.
* If failed, then we will attempt to ask the file system for parent vnode.
* This is just a best effort as both attempts could still fail.
*/
if (need_parent) {
dvp = vnode_getparent(vp);
if (__improbable(dvp == NULLVP)) {
dvp = vnode_getparent_byid(vp);
}
} else {
dvp = vp;
}
if (__probable(dvp != NULLVP)) {
/* Always break dir leases. */
(void)vnode_breaklease(dvp, oflags, vfs_context_current());
}
if (need_parent && (dvp != NULLVP)) {
vnode_put(dvp);
}
}
/*
* Revoke all lease(s) in place for the file.
* This is called when the vnode is reclaimed.
*/
void
vnode_revokelease(vnode_t vp, bool locked)
{
file_lease_t fl, fl_tmp;
bool need_wakeup = false;
if ((vnode_vtype(vp) != VREG && vnode_vtype(vp) != VDIR)) {
return;
}
if (!locked) {
vnode_lock(vp);
}
LIST_FOREACH_SAFE(fl, &vp->v_leases, fl_link, fl_tmp) {
LIST_REMOVE(fl, fl_link);
file_lease_free(fl);
need_wakeup = true;
}
/* Wakeup any lease breaker(s) that might be currently blocked. */
if (__improbable(need_wakeup)) {
wakeup(&vp->v_leases);
}
if (!locked) {
vnode_unlock(vp);
}
}
#endif /* CONFIG_FILE_LEASES */
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