gems-kernel/source/THIRDPARTY/xnu/bsd/sys/namei.h

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/*
* Copyright (c) 2000-2014 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) 1985, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*
* @(#)namei.h 8.4 (Berkeley) 8/20/94
*/
#ifndef _SYS_NAMEI_H_
#define _SYS_NAMEI_H_
#include <sys/appleapiopts.h>
#ifdef KERNEL
#define LOCKLEAF 0x0004 /* lock inode on return */
#define LOCKPARENT 0x0008 /* want parent vnode returned */
#define WANTPARENT 0x0010 /* want parent vnode returned */
#ifdef KERNEL_PRIVATE
#define CN_SECLUDE_RENAME 0x10000000 /*rename iff ¬(hard-linked opened mmaped)*/
#define CN_RAW_ENCRYPTED 0x80000000 /* Look-up is for RO raw encrypted access. */
#endif
#endif // KERNEL
#ifdef BSD_KERNEL_PRIVATE
/* VFS Supports "/..namedfork/rsrc" access. */
#define NAMEDRSRCFORK NAMEDSTREAMS
#include <sys/queue.h>
#include <kern/smr.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/filedesc.h>
#define PATHBUFLEN 256
/*
* Encapsulation of namei parameters.
*/
struct nameidata {
/*
* Arguments to namei/lookup.
*/
user_addr_t ni_dirp; /* pathname pointer */
enum uio_seg ni_segflg; /* location of pathname */
enum path_operation ni_op; /* intended operation, see enum path_operation in vnode.h */
/*
* Arguments to lookup.
*/
struct vnode *ni_startdir; /* starting directory */
struct vnode *ni_rootdir; /* logical root directory */
struct vnode *ni_usedvp; /* directory passed in via USEDVP */
/*
* Results: returned from/manipulated by lookup
*/
struct vnode *ni_vp; /* vnode of result */
struct vnode *ni_dvp; /* vnode of intermediate directory */
/*
* Shared between namei and lookup/commit routines.
*/
u_int ni_pathlen; /* remaining chars in path */
char *ni_next; /* next location in pathname */
char ni_pathbuf[PATHBUFLEN];
u_long ni_loopcnt; /* count of symlinks encountered */
struct componentname ni_cnd;
int32_t ni_flag;
int ni_ncgeneration; /* For a batched vnop, grab generation beforehand */
};
#define NAMEI_CONTLOOKUP 0x002 /* Continue processing a lookup which was partially processed in a compound VNOP */
#define NAMEI_TRAILINGSLASH 0x004 /* There was at least one trailing slash after last component */
#define NAMEI_UNFINISHED 0x008 /* We broke off a lookup to do a compound op */
/*
* XXX Hack: we need to encode the intended VNOP in order to
* be able to include information about which operations a filesystem
* supports in the decision to break off a lookup early.
*/
#define NAMEI_COMPOUNDOPEN 0x010
#define NAMEI_COMPOUNDREMOVE 0x020
#define NAMEI_COMPOUNDMKDIR 0x040
#define NAMEI_COMPOUNDRMDIR 0x080
#define NAMEI_COMPOUNDRENAME 0x100
#define NAMEI_COMPOUND_OP_MASK (NAMEI_COMPOUNDOPEN | NAMEI_COMPOUNDREMOVE | NAMEI_COMPOUNDMKDIR | NAMEI_COMPOUNDRMDIR | NAMEI_COMPOUNDRENAME)
#define NAMEI_NOFOLLOW_ANY 0x1000 /* no symlinks allowed in the path */
#define NAMEI_ROOTDIR 0x2000 /* Limit lookup to ni_rootdir (similar to chroot) */
#ifdef KERNEL
/*
* namei operational modifier flags, stored in ni_cnd.flags
* Also includes LOCKLEAF, LOCKPARENT, and WANTPARENT flags, defined above.
*/
#define NOCACHE 0x00000020 /* name must not be left in cache */
#define NOFOLLOW 0x00000000 /* do not follow symbolic links (pseudo) */
/* public FOLLOW 0x00000040 see vnode.h */
#define SHAREDLEAF 0x00000080 /* OK to have shared leaf lock */
#define MODMASK 0x100000fc /* mask of operational modifiers */
/*
* Namei parameter descriptors.
*
* SAVESTART is set only by the callers of namei. It implies SAVENAME
* plus the addition of saving the parent directory that contains the
* name in ni_startdir. It allows repeated calls to lookup for the
* name being sought. The caller is responsible for releasing the
* buffer and for vrele'ing ni_startdir.
*/
#define SAVENAME 0 /* save pathanme buffer ***obsolete */
#define NOCROSSMOUNT 0x00000100 /* do not cross mount points */
#define RDONLY 0x00000200 /* lookup with read-only semantics */
#define HASBUF 0x00000400 /* has allocated pathname buffer */
#define DONOTAUTH 0x00000800 /* do not authorize during lookup */
#define SAVESTART 0x00001000 /* save starting directory */
/* public ISDOTDOT 0x00002000 see vnode.h */
/* public MAKEENTRY 0x00004000 see vnode.h */
/* public ISLASTCN 0x00008000 see vnode.h */
#define ISSYMLINK 0x00010000 /* symlink needs interpretation */
/* public ISWHITEOUT 0x00020000 see vnode.h */
/* public DOWHITEOUT 0x00040000 see vnode.h */
#define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */
#define AUDITVNPATH1 0x00100000 /* audit the path/vnode info */
#define AUDITVNPATH2 0x00200000 /* audit the path/vnode info */
#define USEDVP 0x00400000 /* start the lookup at ndp.ni_dvp */
#define CN_VOLFSPATH 0x00800000 /* user path was a volfs style path */
#define CN_FIRMLINK_NOFOLLOW 0x01000000 /* Do not follow firm links */
#define UNIONCREATED 0x02000000 /* union fs creation of vnode */
#if NAMEDRSRCFORK
#define CN_WANTSRSRCFORK 0x04000000
#define CN_ALLOWRSRCFORK 0x08000000
#endif // NAMEDRSRCFORK
// CN_SECLUDE_RENAME is defined above as 0x10000000 (SPI)
#define CN_NBMOUNTLOOK 0x20000000 /* do not block for cross mount lookups */
#ifdef BSD_KERNEL_PRIVATE
#define CN_SKIPNAMECACHE 0x40000000 /* skip cache during lookup(), allow FS to handle all components */
#endif
// CN_RAW_ENCRYPTED is defined above as 0x80000000 (SPI)
/*
* Initialization of an nameidata structure.
*/
#define NDINIT(ndp, op, pop, flags, segflg, namep, ctx) { \
(ndp)->ni_cnd.cn_nameiop = op; \
(ndp)->ni_op = pop; \
(ndp)->ni_cnd.cn_flags = flags; \
if ((segflg) == UIO_USERSPACE) { \
(ndp)->ni_segflg = (vfs_context_is64bit(ctx) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
} \
else { \
(ndp)->ni_segflg = segflg; \
} \
(ndp)->ni_dirp = namep; \
(ndp)->ni_cnd.cn_context = ctx; \
(ndp)->ni_flag = 0; \
(ndp)->ni_cnd.cn_ndp = (ndp); \
}
#endif /* KERNEL */
/*
* This structure describes the elements in the cache of recent
* names looked up by namei.
*/
struct namecache {
TAILQ_ENTRY(namecache) nc_entry; /* chain of all entries */
TAILQ_ENTRY(namecache) nc_child; /* chain of ncp's that are children of a vp */
union {
LIST_ENTRY(namecache) nc_link; /* chain of ncp's that 'name' a vp */
TAILQ_ENTRY(namecache) nc_negentry; /* chain of ncp's that 'name' a vp */
} nc_un;
struct smrq_link nc_hash; /* hash chain */
uint32_t nc_vid; /* vid for nc_vp */
uint32_t nc_counter; /* flags */
vnode_t nc_dvp; /* vnode of parent of name */
vnode_t nc_vp; /* vnode the name refers to */
unsigned int nc_hashval; /* hashval of stringname */
const char *nc_name; /* pointer to segment name in string cache */
};
#define NC_VALID 0x01 /* counter value with this bit set (i.e. odd number) represents an valid/in-use namecache struct */
#ifdef KERNEL
int namei(struct nameidata *ndp);
void nameidone(struct nameidata *);
int lookup(struct nameidata *ndp);
int relookup(struct vnode *dvp, struct vnode **vpp,
struct componentname *cnp);
#if CONFIG_UNION_MOUNTS
int lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx);
#endif /* CONFIG_UNION_MOUNTS */
void lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameidata *ndp, int did_create);
void kdebug_lookup(struct vnode *dp, struct componentname *cnp);
/*
* namecache function prototypes
*/
void cache_purgevfs(mount_t mp);
int cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
vfs_context_t context, int *dp_authorized, vnode_t last_dp);
void vnode_cache_authorized_action(vnode_t vp, vfs_context_t context, kauth_action_t action);
void vnode_uncache_authorized_action(vnode_t vp, kauth_action_t action);
boolean_t vnode_cache_is_stale(vnode_t vp);
boolean_t vnode_cache_is_authorized(vnode_t vp, vfs_context_t context, kauth_action_t action);
int lookup_validate_creation_path(struct nameidata *ndp);
int namei_compound_available(vnode_t dp, struct nameidata *ndp);
#endif /* KERNEL */
/*
* Stats on usefulness of namei caches.
*/
struct nchstats {
long ncs_goodhits; /* hits that we can really use */
long ncs_neghits; /* negative hits that we can use */
long ncs_badhits; /* hits we must drop */
long ncs_miss; /* misses */
long ncs_pass2; /* names found with passes == 2 */
long ncs_2passes; /* number of times we attempt it */
long ncs_stolen;
long ncs_enters;
long ncs_deletes;
long ncs_badvid;
};
#endif /* BSD_KERNEL_PRIVATE */
#endif /* !_SYS_NAMEI_H_ */