/* * Copyright (c) 2000-2020 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) 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. * * @(#)vfs_cluster.c 8.10 (Berkeley) 3/28/95 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if 0 #undef KERNEL_DEBUG #define KERNEL_DEBUG KERNEL_DEBUG_CONSTANT #endif #define CL_READ 0x01 #define CL_WRITE 0x02 #define CL_ASYNC 0x04 #define CL_COMMIT 0x08 #define CL_PAGEOUT 0x10 #define CL_AGE 0x20 #define CL_NOZERO 0x40 #define CL_PAGEIN 0x80 #define CL_DEV_MEMORY 0x100 #define CL_PRESERVE 0x200 #define CL_THROTTLE 0x400 #define CL_KEEPCACHED 0x800 #define CL_DIRECT_IO 0x1000 #define CL_PASSIVE 0x2000 #define CL_IOSTREAMING 0x4000 #define CL_CLOSE 0x8000 #define CL_ENCRYPTED 0x10000 #define CL_RAW_ENCRYPTED 0x20000 #define CL_NOCACHE 0x40000 #define MAX_VECTOR_UPL_SIZE (2 * MAX_UPL_SIZE_BYTES) #define CLUSTER_IO_WAITING ((buf_t)1) extern upl_t vector_upl_create(vm_offset_t, uint32_t); extern uint32_t vector_upl_max_upls(upl_t); extern boolean_t vector_upl_is_valid(upl_t); extern boolean_t vector_upl_set_subupl(upl_t, upl_t, u_int32_t); extern void vector_upl_set_pagelist(upl_t); extern void vector_upl_set_iostate(upl_t, upl_t, vm_offset_t, u_int32_t); struct clios { lck_mtx_t io_mtxp; u_int io_completed; /* amount of io that has currently completed */ u_int io_issued; /* amount of io that was successfully issued */ int io_error; /* error code of first error encountered */ int io_wanted; /* someone is sleeping waiting for a change in state */ }; struct cl_direct_read_lock { LIST_ENTRY(cl_direct_read_lock) chain; int32_t ref_count; vnode_t vp; lck_rw_t rw_lock; }; #define CL_DIRECT_READ_LOCK_BUCKETS 61 static LIST_HEAD(cl_direct_read_locks, cl_direct_read_lock) cl_direct_read_locks[CL_DIRECT_READ_LOCK_BUCKETS]; static LCK_GRP_DECLARE(cl_mtx_grp, "cluster I/O"); static LCK_MTX_DECLARE(cl_transaction_mtxp, &cl_mtx_grp); static LCK_SPIN_DECLARE(cl_direct_read_spin_lock, &cl_mtx_grp); static ZONE_DEFINE(cl_rd_zone, "cluster_read", sizeof(struct cl_readahead), ZC_ZFREE_CLEARMEM); static ZONE_DEFINE(cl_wr_zone, "cluster_write", sizeof(struct cl_writebehind), ZC_ZFREE_CLEARMEM); #define IO_UNKNOWN 0 #define IO_DIRECT 1 #define IO_CONTIG 2 #define IO_COPY 3 #define PUSH_DELAY 0x01 #define PUSH_ALL 0x02 #define PUSH_SYNC 0x04 static void cluster_EOT(buf_t cbp_head, buf_t cbp_tail, int zero_offset, size_t verify_block_size); static void cluster_wait_IO(buf_t cbp_head, int async); static void cluster_complete_transaction(buf_t *cbp_head, void *callback_arg, int *retval, int flags, int needwait); static int cluster_io_type(struct uio *uio, int *io_type, u_int32_t *io_length, u_int32_t min_length); static int cluster_io(vnode_t vp, upl_t upl, vm_offset_t upl_offset, off_t f_offset, int non_rounded_size, int flags, buf_t real_bp, struct clios *iostate, int (*)(buf_t, void *), void *callback_arg); static int cluster_iodone(buf_t bp, void *callback_arg); static int cluster_ioerror(upl_t upl, int upl_offset, int abort_size, int error, int io_flags, vnode_t vp); static int cluster_is_throttled(vnode_t vp); static void cluster_iostate_wait(struct clios *iostate, u_int target, const char *wait_name); static void cluster_syncup(vnode_t vp, off_t newEOF, int (*)(buf_t, void *), void *callback_arg, int flags); static void cluster_read_upl_release(upl_t upl, int start_pg, int last_pg, int take_reference); static int cluster_copy_ubc_data_internal(vnode_t vp, struct uio *uio, int *io_resid, int mark_dirty, int take_reference); static int cluster_read_copy(vnode_t vp, struct uio *uio, u_int32_t io_req_size, off_t filesize, int flags, int (*)(buf_t, void *), void *callback_arg) __attribute__((noinline)); static int cluster_read_direct(vnode_t vp, struct uio *uio, off_t filesize, int *read_type, u_int32_t *read_length, int flags, int (*)(buf_t, void *), void *callback_arg) __attribute__((noinline)); static int cluster_read_contig(vnode_t vp, struct uio *uio, off_t filesize, int *read_type, u_int32_t *read_length, int (*)(buf_t, void *), void *callback_arg, int flags) __attribute__((noinline)); static int cluster_write_copy(vnode_t vp, struct uio *uio, u_int32_t io_req_size, off_t oldEOF, off_t newEOF, off_t headOff, off_t tailOff, int flags, int (*)(buf_t, void *), void *callback_arg) __attribute__((noinline)); static int cluster_write_direct(vnode_t vp, struct uio *uio, off_t oldEOF, off_t newEOF, int *write_type, u_int32_t *write_length, int flags, int (*)(buf_t, void *), void *callback_arg) __attribute__((noinline)); static int cluster_write_contig(vnode_t vp, struct uio *uio, off_t newEOF, int *write_type, u_int32_t *write_length, int (*)(buf_t, void *), void *callback_arg, int bflag) __attribute__((noinline)); static void cluster_update_state_internal(vnode_t vp, struct cl_extent *cl, int flags, boolean_t defer_writes, boolean_t *first_pass, off_t write_off, int write_cnt, off_t newEOF, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated); static int cluster_align_phys_io(vnode_t vp, struct uio *uio, addr64_t usr_paddr, u_int32_t xsize, int flags, int (*)(buf_t, void *), void *callback_arg); static int cluster_read_prefetch(vnode_t vp, off_t f_offset, u_int size, off_t filesize, int (*callback)(buf_t, void *), void *callback_arg, int bflag); static void cluster_read_ahead(vnode_t vp, struct cl_extent *extent, off_t filesize, struct cl_readahead *ra, int (*callback)(buf_t, void *), void *callback_arg, int bflag); static int cluster_push_now(vnode_t vp, struct cl_extent *, off_t EOF, int flags, int (*)(buf_t, void *), void *callback_arg, boolean_t vm_ioitiated); static int cluster_try_push(struct cl_writebehind *, vnode_t vp, off_t EOF, int push_flag, int flags, int (*)(buf_t, void *), void *callback_arg, int *err, boolean_t vm_initiated); static int sparse_cluster_switch(struct cl_writebehind *, vnode_t vp, off_t EOF, int (*)(buf_t, void *), void *callback_arg, boolean_t vm_initiated); static int sparse_cluster_push(struct cl_writebehind *, void **cmapp, vnode_t vp, off_t EOF, int push_flag, int io_flags, int (*)(buf_t, void *), void *callback_arg, boolean_t vm_initiated); static int sparse_cluster_add(struct cl_writebehind *, void **cmapp, vnode_t vp, struct cl_extent *, off_t EOF, int (*)(buf_t, void *), void *callback_arg, boolean_t vm_initiated); static kern_return_t vfs_drt_mark_pages(void **cmapp, off_t offset, u_int length, u_int *setcountp); static kern_return_t vfs_drt_get_cluster(void **cmapp, off_t *offsetp, u_int *lengthp); static kern_return_t vfs_drt_control(void **cmapp, int op_type); static kern_return_t vfs_get_scmap_push_behavior_internal(void **cmapp, int *push_flag); /* * For throttled IO to check whether * a block is cached by the boot cache * and thus it can avoid delaying the IO. * * bootcache_contains_block is initially * NULL. The BootCache will set it while * the cache is active and clear it when * the cache is jettisoned. * * Returns 0 if the block is not * contained in the cache, 1 if it is * contained. * * The function pointer remains valid * after the cache has been evicted even * if bootcache_contains_block has been * cleared. * * See rdar://9974130 The new throttling mechanism breaks the boot cache for throttled IOs */ int (*bootcache_contains_block)(dev_t device, u_int64_t blkno) = NULL; /* * limit the internal I/O size so that we * can represent it in a 32 bit int */ #define MAX_IO_REQUEST_SIZE (1024 * 1024 * 512) #define MAX_IO_CONTIG_SIZE MAX_UPL_SIZE_BYTES #define MAX_VECTS 16 /* * The MIN_DIRECT_WRITE_SIZE governs how much I/O should be issued before we consider * allowing the caller to bypass the buffer cache. For small I/Os (less than 16k), * we have not historically allowed the write to bypass the UBC. */ #define MIN_DIRECT_WRITE_SIZE (16384) #define WRITE_THROTTLE 6 #define WRITE_THROTTLE_SSD 2 #define WRITE_BEHIND 1 #define WRITE_BEHIND_SSD 1 #if !defined(XNU_TARGET_OS_OSX) #define PREFETCH 1 #define PREFETCH_SSD 1 uint32_t speculative_prefetch_max = (2048 * 1024); /* maximum bytes in a specluative read-ahead */ uint32_t speculative_prefetch_max_iosize = (512 * 1024); /* maximum I/O size to use in a specluative read-ahead */ #else /* XNU_TARGET_OS_OSX */ #define PREFETCH 3 #define PREFETCH_SSD 2 uint32_t speculative_prefetch_max = (MAX_UPL_SIZE_BYTES * 3); /* maximum bytes in a specluative read-ahead */ uint32_t speculative_prefetch_max_iosize = (512 * 1024); /* maximum I/O size to use in a specluative read-ahead on SSDs*/ #endif /* ! XNU_TARGET_OS_OSX */ /* maximum bytes for read-ahead */ uint32_t prefetch_max = (1024 * 1024 * 1024); /* maximum bytes for outstanding reads */ uint32_t overlapping_read_max = (1024 * 1024 * 1024); /* maximum bytes for outstanding writes */ uint32_t overlapping_write_max = (1024 * 1024 * 1024); #define IO_SCALE(vp, base) (vp->v_mount->mnt_ioscale * (base)) #define MAX_CLUSTER_SIZE(vp) (cluster_max_io_size(vp->v_mount, CL_WRITE)) int speculative_reads_disabled = 0; /* * throttle the number of async writes that * can be outstanding on a single vnode * before we issue a synchronous write */ #define THROTTLE_MAXCNT 0 uint32_t throttle_max_iosize = (128 * 1024); #define THROTTLE_MAX_IOSIZE (throttle_max_iosize) SYSCTL_INT(_debug, OID_AUTO, lowpri_throttle_max_iosize, CTLFLAG_RW | CTLFLAG_LOCKED, &throttle_max_iosize, 0, ""); void cluster_init(void) { for (int i = 0; i < CL_DIRECT_READ_LOCK_BUCKETS; ++i) { LIST_INIT(&cl_direct_read_locks[i]); } } uint32_t cluster_max_io_size(mount_t mp, int type) { uint32_t max_io_size; uint32_t segcnt; uint32_t maxcnt; switch (type) { case CL_READ: segcnt = mp->mnt_segreadcnt; maxcnt = mp->mnt_maxreadcnt; break; case CL_WRITE: segcnt = mp->mnt_segwritecnt; maxcnt = mp->mnt_maxwritecnt; break; default: segcnt = min(mp->mnt_segreadcnt, mp->mnt_segwritecnt); maxcnt = min(mp->mnt_maxreadcnt, mp->mnt_maxwritecnt); break; } if (segcnt > (MAX_UPL_SIZE_BYTES >> PAGE_SHIFT)) { /* * don't allow a size beyond the max UPL size we can create */ segcnt = MAX_UPL_SIZE_BYTES >> PAGE_SHIFT; } max_io_size = min((segcnt * PAGE_SIZE), maxcnt); if (max_io_size < MAX_UPL_TRANSFER_BYTES) { /* * don't allow a size smaller than the old fixed limit */ max_io_size = MAX_UPL_TRANSFER_BYTES; } else { /* * make sure the size specified is a multiple of PAGE_SIZE */ max_io_size &= ~PAGE_MASK; } return max_io_size; } /* * Returns max prefetch value. If the value overflows or exceeds the specified * 'prefetch_limit', it will be capped at 'prefetch_limit' value. */ static inline uint32_t cluster_max_prefetch(vnode_t vp, uint32_t max_io_size, uint32_t prefetch_limit) { bool is_ssd = disk_conditioner_mount_is_ssd(vp->v_mount); uint32_t io_scale = IO_SCALE(vp, is_ssd ? PREFETCH_SSD : PREFETCH); uint32_t prefetch = 0; if (__improbable(os_mul_overflow(max_io_size, io_scale, &prefetch) || (prefetch > prefetch_limit))) { prefetch = prefetch_limit; } return prefetch; } static inline uint32_t calculate_max_throttle_size(vnode_t vp) { bool is_ssd = disk_conditioner_mount_is_ssd(vp->v_mount); uint32_t io_scale = IO_SCALE(vp, is_ssd ? 2 : 1); return MIN(io_scale * THROTTLE_MAX_IOSIZE, MAX_UPL_TRANSFER_BYTES); } static inline uint32_t calculate_max_throttle_cnt(vnode_t vp) { bool is_ssd = disk_conditioner_mount_is_ssd(vp->v_mount); uint32_t io_scale = IO_SCALE(vp, 1); return is_ssd ? MIN(io_scale, 4) : THROTTLE_MAXCNT; } #define CLW_ALLOCATE 0x01 #define CLW_RETURNLOCKED 0x02 #define CLW_IONOCACHE 0x04 #define CLW_IOPASSIVE 0x08 /* * if the read ahead context doesn't yet exist, * allocate and initialize it... * the vnode lock serializes multiple callers * during the actual assignment... first one * to grab the lock wins... the other callers * will release the now unnecessary storage * * once the context is present, try to grab (but don't block on) * the lock associated with it... if someone * else currently owns it, than the read * will run without read-ahead. this allows * multiple readers to run in parallel and * since there's only 1 read ahead context, * there's no real loss in only allowing 1 * reader to have read-ahead enabled. */ static struct cl_readahead * cluster_get_rap(vnode_t vp) { struct ubc_info *ubc; struct cl_readahead *rap; ubc = vp->v_ubcinfo; if ((rap = ubc->cl_rahead) == NULL) { rap = zalloc_flags(cl_rd_zone, Z_WAITOK | Z_ZERO); rap->cl_lastr = -1; lck_mtx_init(&rap->cl_lockr, &cl_mtx_grp, LCK_ATTR_NULL); vnode_lock(vp); if (ubc->cl_rahead == NULL) { ubc->cl_rahead = rap; } else { lck_mtx_destroy(&rap->cl_lockr, &cl_mtx_grp); zfree(cl_rd_zone, rap); rap = ubc->cl_rahead; } vnode_unlock(vp); } if (lck_mtx_try_lock(&rap->cl_lockr) == TRUE) { return rap; } return (struct cl_readahead *)NULL; } /* * if the write behind context doesn't yet exist, * and CLW_ALLOCATE is specified, allocate and initialize it... * the vnode lock serializes multiple callers * during the actual assignment... first one * to grab the lock wins... the other callers * will release the now unnecessary storage * * if CLW_RETURNLOCKED is set, grab (blocking if necessary) * the lock associated with the write behind context before * returning */ static struct cl_writebehind * cluster_get_wbp(vnode_t vp, int flags) { struct ubc_info *ubc; struct cl_writebehind *wbp; ubc = vp->v_ubcinfo; if ((wbp = ubc->cl_wbehind) == NULL) { if (!(flags & CLW_ALLOCATE)) { return (struct cl_writebehind *)NULL; } wbp = zalloc_flags(cl_wr_zone, Z_WAITOK | Z_ZERO); lck_mtx_init(&wbp->cl_lockw, &cl_mtx_grp, LCK_ATTR_NULL); vnode_lock(vp); if (ubc->cl_wbehind == NULL) { ubc->cl_wbehind = wbp; } else { lck_mtx_destroy(&wbp->cl_lockw, &cl_mtx_grp); zfree(cl_wr_zone, wbp); wbp = ubc->cl_wbehind; } vnode_unlock(vp); } if (flags & CLW_RETURNLOCKED) { lck_mtx_lock(&wbp->cl_lockw); } return wbp; } static void cluster_syncup(vnode_t vp, off_t newEOF, int (*callback)(buf_t, void *), void *callback_arg, int flags) { struct cl_writebehind *wbp; if ((wbp = cluster_get_wbp(vp, 0)) != NULL) { if (wbp->cl_number) { lck_mtx_lock(&wbp->cl_lockw); cluster_try_push(wbp, vp, newEOF, PUSH_ALL | flags, 0, callback, callback_arg, NULL, FALSE); lck_mtx_unlock(&wbp->cl_lockw); } } } static int cluster_io_present_in_BC(vnode_t vp, off_t f_offset) { daddr64_t blkno; size_t io_size; int (*bootcache_check_fn)(dev_t device, u_int64_t blkno) = bootcache_contains_block; if (bootcache_check_fn && vp->v_mount && vp->v_mount->mnt_devvp) { if (VNOP_BLOCKMAP(vp, f_offset, PAGE_SIZE, &blkno, &io_size, NULL, VNODE_READ | VNODE_BLOCKMAP_NO_TRACK, NULL)) { return 0; } if (io_size == 0) { return 0; } if (bootcache_check_fn(vp->v_mount->mnt_devvp->v_rdev, blkno)) { return 1; } } return 0; } static int cluster_is_throttled(vnode_t vp) { return throttle_io_will_be_throttled(-1, vp->v_mount); } static void cluster_iostate_wait(struct clios *iostate, u_int target, const char *wait_name) { lck_mtx_lock(&iostate->io_mtxp); while ((iostate->io_issued - iostate->io_completed) > target) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 95)) | DBG_FUNC_START, iostate->io_issued, iostate->io_completed, target, 0, 0); iostate->io_wanted = 1; msleep((caddr_t)&iostate->io_wanted, &iostate->io_mtxp, PRIBIO + 1, wait_name, NULL); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 95)) | DBG_FUNC_END, iostate->io_issued, iostate->io_completed, target, 0, 0); } lck_mtx_unlock(&iostate->io_mtxp); } static void cluster_handle_associated_upl(struct clios *iostate, upl_t upl, upl_offset_t upl_offset, upl_size_t size) { if (!size) { return; } upl_t associated_upl = upl_associated_upl(upl); if (!associated_upl) { return; } #if 0 printf("1: %d %d\n", upl_offset, upl_offset + size); #endif /* * The associated UPL is page aligned to file offsets whereas the * UPL it's attached to has different alignment requirements. The * upl_offset that we have refers to @upl. The code that follows * has to deal with the first and last pages in this transaction * which might straddle pages in the associated UPL. To keep * track of these pages, we use the mark bits: if the mark bit is * set, we know another transaction has completed its part of that * page and so we can unlock that page here. * * The following illustrates what we have to deal with: * * MEM u <------------ 1 PAGE ------------> e * +-------------+----------------------+----------------- * | |######################|################# * +-------------+----------------------+----------------- * FILE | <--- a ---> o <------------ 1 PAGE ------------> * * So here we show a write to offset @o. The data that is to be * written is in a buffer that is not page aligned; it has offset * @a in the page. The upl that carries the data starts in memory * at @u. The associated upl starts in the file at offset @o. A * transaction will always end on a page boundary (like @e above) * except for the very last transaction in the group. We cannot * unlock the page at @o in the associated upl until both the * transaction ending at @e and the following transaction (that * starts at @e) has completed. */ /* * We record whether or not the two UPLs are aligned as the mark * bit in the first page of @upl. */ upl_page_info_t *pl = UPL_GET_INTERNAL_PAGE_LIST(upl); bool is_unaligned = upl_page_get_mark(pl, 0); if (is_unaligned) { upl_page_info_t *assoc_pl = UPL_GET_INTERNAL_PAGE_LIST(associated_upl); upl_offset_t upl_end = upl_offset + size; assert(upl_end >= PAGE_SIZE); upl_size_t assoc_upl_size = upl_get_size(associated_upl); /* * In the very first transaction in the group, upl_offset will * not be page aligned, but after that it will be and in that * case we want the preceding page in the associated UPL hence * the minus one. */ assert(upl_offset); if (upl_offset) { upl_offset = trunc_page_32(upl_offset - 1); } lck_mtx_lock_spin(&iostate->io_mtxp); // Look at the first page... if (upl_offset && !upl_page_get_mark(assoc_pl, upl_offset >> PAGE_SHIFT)) { /* * The first page isn't marked so let another transaction * completion handle it. */ upl_page_set_mark(assoc_pl, upl_offset >> PAGE_SHIFT, true); upl_offset += PAGE_SIZE; } // And now the last page... /* * This needs to be > rather than >= because if it's equal, it * means there's another transaction that is sharing the last * page. */ if (upl_end > assoc_upl_size) { upl_end = assoc_upl_size; } else { upl_end = trunc_page_32(upl_end); const int last_pg = (upl_end >> PAGE_SHIFT) - 1; if (!upl_page_get_mark(assoc_pl, last_pg)) { /* * The last page isn't marked so mark the page and let another * transaction completion handle it. */ upl_page_set_mark(assoc_pl, last_pg, true); upl_end -= PAGE_SIZE; } } lck_mtx_unlock(&iostate->io_mtxp); #if 0 printf("2: %d %d\n", upl_offset, upl_end); #endif if (upl_end <= upl_offset) { return; } size = upl_end - upl_offset; } else { assert(!(upl_offset & PAGE_MASK)); assert(!(size & PAGE_MASK)); } boolean_t empty; /* * We can unlock these pages now and as this is for a * direct/uncached write, we want to dump the pages too. */ kern_return_t kr = upl_abort_range(associated_upl, upl_offset, size, UPL_ABORT_DUMP_PAGES, &empty); assert(!kr); if (!kr && empty) { upl_set_associated_upl(upl, NULL); upl_deallocate(associated_upl); } } static int cluster_ioerror(upl_t upl, int upl_offset, int abort_size, int error, int io_flags, vnode_t vp) { int upl_abort_code = 0; int page_in = 0; int page_out = 0; if ((io_flags & (B_PHYS | B_CACHE)) == (B_PHYS | B_CACHE)) { /* * direct write of any flavor, or a direct read that wasn't aligned */ ubc_upl_commit_range(upl, upl_offset, abort_size, UPL_COMMIT_FREE_ON_EMPTY); } else { if (io_flags & B_PAGEIO) { if (io_flags & B_READ) { page_in = 1; } else { page_out = 1; } } if (io_flags & B_CACHE) { /* * leave pages in the cache unchanged on error */ upl_abort_code = UPL_ABORT_FREE_ON_EMPTY; } else if (((io_flags & B_READ) == 0) && ((error != ENXIO) || vnode_isswap(vp))) { /* * transient error on pageout/write path... leave pages unchanged */ upl_abort_code = UPL_ABORT_FREE_ON_EMPTY; } else if (page_in) { upl_abort_code = UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_ERROR; } else { upl_abort_code = UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_DUMP_PAGES; } ubc_upl_abort_range(upl, upl_offset, abort_size, upl_abort_code); } return upl_abort_code; } static int cluster_iodone(buf_t bp, void *callback_arg) { int b_flags; int error; int total_size; int total_resid; int upl_offset; int zero_offset; int pg_offset = 0; int commit_size = 0; int upl_flags = 0; int transaction_size = 0; upl_t upl; buf_t cbp; buf_t cbp_head; buf_t cbp_next; buf_t real_bp; vnode_t vp; struct clios *iostate; void *verify_ctx; boolean_t transaction_complete = FALSE; __IGNORE_WCASTALIGN(cbp_head = (buf_t)(bp->b_trans_head)); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_START, cbp_head, bp->b_lblkno, bp->b_bcount, bp->b_flags, 0); if (cbp_head->b_trans_next || !(cbp_head->b_flags & B_EOT)) { lck_mtx_lock_spin(&cl_transaction_mtxp); bp->b_flags |= B_TDONE; for (cbp = cbp_head; cbp; cbp = cbp->b_trans_next) { /* * all I/O requests that are part of this transaction * have to complete before we can process it */ if (!(cbp->b_flags & B_TDONE)) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END, cbp_head, cbp, cbp->b_bcount, cbp->b_flags, 0); lck_mtx_unlock(&cl_transaction_mtxp); return 0; } if (cbp->b_trans_next == CLUSTER_IO_WAITING) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END, cbp_head, cbp, cbp->b_bcount, cbp->b_flags, 0); lck_mtx_unlock(&cl_transaction_mtxp); wakeup(cbp); return 0; } if (cbp->b_flags & B_EOT) { transaction_complete = TRUE; } } lck_mtx_unlock(&cl_transaction_mtxp); if (transaction_complete == FALSE) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END, cbp_head, 0, 0, 0, 0); return 0; } } error = 0; total_size = 0; total_resid = 0; cbp = cbp_head; vp = cbp->b_vp; upl_offset = cbp->b_uploffset; upl = cbp->b_upl; b_flags = cbp->b_flags; real_bp = cbp->b_real_bp; zero_offset = cbp->b_validend; iostate = (struct clios *)cbp->b_iostate; if (real_bp) { real_bp->b_dev = cbp->b_dev; } while (cbp) { if ((cbp->b_flags & B_ERROR) && error == 0) { error = cbp->b_error; } total_resid += cbp->b_resid; total_size += cbp->b_bcount; cbp_next = cbp->b_trans_next; if (cbp_next == NULL) { /* * compute the overall size of the transaction * in case we created one that has 'holes' in it * 'total_size' represents the amount of I/O we * did, not the span of the transaction w/r to the UPL */ transaction_size = cbp->b_uploffset + cbp->b_bcount - upl_offset; } if (cbp != cbp_head) { free_io_buf(cbp); } cbp = cbp_next; } if (ISSET(b_flags, B_COMMIT_UPL)) { cluster_handle_associated_upl(iostate, cbp_head->b_upl, upl_offset, transaction_size); } if (error == 0 && total_resid) { error = EIO; } if (error == 0) { int (*cliodone_func)(buf_t, void *) = (int (*)(buf_t, void *))(cbp_head->b_cliodone); if (cliodone_func != NULL) { cbp_head->b_bcount = transaction_size; error = (*cliodone_func)(cbp_head, callback_arg); } } if (zero_offset) { cluster_zero(upl, zero_offset, PAGE_SIZE - (zero_offset & PAGE_MASK), real_bp); } verify_ctx = cbp_head->b_attr.ba_verify_ctx; cbp_head->b_attr.ba_verify_ctx = NULL; if (verify_ctx) { vnode_verify_flags_t verify_flags = VNODE_VERIFY_CONTEXT_FREE; caddr_t verify_buf = NULL; off_t start_off = cbp_head->b_lblkno * cbp_head->b_lblksize; size_t verify_length = transaction_size; vm_offset_t vaddr; if (!error) { verify_flags |= VNODE_VERIFY_WITH_CONTEXT; error = ubc_upl_map_range(upl, upl_offset, round_page(transaction_size), VM_PROT_DEFAULT, &vaddr); /* Map it in */ if (error) { panic("ubc_upl_map_range returned error %d, upl = %p, upl_offset = %d, size = %d", error, upl, (int)upl_offset, (int)round_page(transaction_size)); } else { verify_buf = (caddr_t)vaddr; } } error = VNOP_VERIFY(vp, start_off, (uint8_t *)verify_buf, verify_length, 0, &verify_ctx, verify_flags, NULL); if (verify_buf) { (void)ubc_upl_unmap_range(upl, upl_offset, round_page(transaction_size)); verify_buf = NULL; } } else if (cbp_head->b_attr.ba_flags & BA_WILL_VERIFY) { error = EBADMSG; } free_io_buf(cbp_head); if (iostate) { int need_wakeup = 0; /* * someone has issued multiple I/Os asynchrounsly * and is waiting for them to complete (streaming) */ lck_mtx_lock_spin(&iostate->io_mtxp); if (error && iostate->io_error == 0) { iostate->io_error = error; } iostate->io_completed += total_size; if (iostate->io_wanted) { /* * someone is waiting for the state of * this io stream to change */ iostate->io_wanted = 0; need_wakeup = 1; } lck_mtx_unlock(&iostate->io_mtxp); if (need_wakeup) { wakeup((caddr_t)&iostate->io_wanted); } } if (b_flags & B_COMMIT_UPL) { pg_offset = upl_offset & PAGE_MASK; commit_size = (pg_offset + transaction_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if (error) { upl_set_iodone_error(upl, error); upl_flags = cluster_ioerror(upl, upl_offset - pg_offset, commit_size, error, b_flags, vp); } else { upl_flags = UPL_COMMIT_FREE_ON_EMPTY; if ((b_flags & B_PHYS) && (b_flags & B_READ)) { upl_flags |= UPL_COMMIT_SET_DIRTY; } if (b_flags & B_AGE) { upl_flags |= UPL_COMMIT_INACTIVATE; } ubc_upl_commit_range(upl, upl_offset - pg_offset, commit_size, upl_flags); } } if (real_bp) { if (error) { real_bp->b_flags |= B_ERROR; real_bp->b_error = error; } real_bp->b_resid = total_resid; buf_biodone(real_bp); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END, upl, upl_offset - pg_offset, commit_size, (error << 24) | upl_flags, 0); return error; } uint32_t cluster_throttle_io_limit(vnode_t vp, uint32_t *limit) { if (cluster_is_throttled(vp)) { *limit = calculate_max_throttle_size(vp); return 1; } return 0; } void cluster_zero(upl_t upl, upl_offset_t upl_offset, int size, buf_t bp) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 23)) | DBG_FUNC_START, upl_offset, size, bp, 0, 0); if (bp == NULL || bp->b_datap == 0) { upl_page_info_t *pl; addr64_t zero_addr; pl = ubc_upl_pageinfo(upl); if (upl_device_page(pl) == TRUE) { zero_addr = ((addr64_t)upl_phys_page(pl, 0) << PAGE_SHIFT) + upl_offset; bzero_phys_nc(zero_addr, size); } else { while (size) { int page_offset; int page_index; int zero_cnt; page_index = upl_offset / PAGE_SIZE; page_offset = upl_offset & PAGE_MASK; zero_addr = ((addr64_t)upl_phys_page(pl, page_index) << PAGE_SHIFT) + page_offset; zero_cnt = min(PAGE_SIZE - page_offset, size); bzero_phys(zero_addr, zero_cnt); size -= zero_cnt; upl_offset += zero_cnt; } } } else { bzero((caddr_t)((vm_offset_t)bp->b_datap + upl_offset), size); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 23)) | DBG_FUNC_END, upl_offset, size, 0, 0, 0); } static void cluster_EOT(buf_t cbp_head, buf_t cbp_tail, int zero_offset, size_t verify_block_size) { /* * We will assign a verification context to cbp_head. * This will be passed back to the filesystem when * verifying (in cluster_iodone). */ if (verify_block_size) { off_t start_off = cbp_head->b_lblkno * cbp_head->b_lblksize; size_t length; void *verify_ctx = NULL; int error = 0; vnode_t vp = buf_vnode(cbp_head); if (cbp_head == cbp_tail) { length = cbp_head->b_bcount; } else { length = ((cbp_tail->b_lblkno * cbp_tail->b_lblksize) + cbp_tail->b_bcount) - start_off; } /* * zero_offset is non zero for the transaction containing the EOF * (if the filesize is not page aligned). In that case we might * have the transaction size not be page/verify block size aligned */ if ((zero_offset == 0) && ((length < verify_block_size) || (length % verify_block_size)) != 0) { panic("%s length = %zu, verify_block_size = %zu", __FUNCTION__, length, verify_block_size); } error = VNOP_VERIFY(vp, start_off, NULL, length, &verify_block_size, &verify_ctx, VNODE_VERIFY_CONTEXT_ALLOC, NULL); cbp_head->b_attr.ba_verify_ctx = verify_ctx; } else { cbp_head->b_attr.ba_verify_ctx = NULL; } cbp_head->b_validend = zero_offset; cbp_tail->b_flags |= B_EOT; } static void cluster_wait_IO(buf_t cbp_head, int async) { buf_t cbp; if (async) { /* * Async callback completion will not normally generate a * wakeup upon I/O completion. To get woken up, we set * b_trans_next (which is safe for us to modify) on the last * buffer to CLUSTER_IO_WAITING so that cluster_iodone knows * to wake us up when all buffers as part of this transaction * are completed. This is done under the umbrella of * cl_transaction_mtxp which is also taken in cluster_iodone. */ bool done = true; buf_t last = NULL; lck_mtx_lock_spin(&cl_transaction_mtxp); for (cbp = cbp_head; cbp; last = cbp, cbp = cbp->b_trans_next) { if (!ISSET(cbp->b_flags, B_TDONE)) { done = false; } } if (!done) { last->b_trans_next = CLUSTER_IO_WAITING; DTRACE_IO1(wait__start, buf_t, last); do { msleep(last, &cl_transaction_mtxp, PSPIN | (PRIBIO + 1), "cluster_wait_IO", NULL); /* * We should only have been woken up if all the * buffers are completed, but just in case... */ done = true; for (cbp = cbp_head; cbp != CLUSTER_IO_WAITING; cbp = cbp->b_trans_next) { if (!ISSET(cbp->b_flags, B_TDONE)) { done = false; break; } } } while (!done); DTRACE_IO1(wait__done, buf_t, last); last->b_trans_next = NULL; } lck_mtx_unlock(&cl_transaction_mtxp); } else { // !async for (cbp = cbp_head; cbp; cbp = cbp->b_trans_next) { buf_biowait(cbp); } } } static void cluster_complete_transaction(buf_t *cbp_head, void *callback_arg, int *retval, int flags, int needwait) { buf_t cbp; int error; boolean_t isswapout = FALSE; /* * cluster_complete_transaction will * only be called if we've issued a complete chain in synchronous mode * or, we've already done a cluster_wait_IO on an incomplete chain */ if (needwait) { for (cbp = *cbp_head; cbp; cbp = cbp->b_trans_next) { buf_biowait(cbp); } } /* * we've already waited on all of the I/Os in this transaction, * so mark all of the buf_t's in this transaction as B_TDONE * so that cluster_iodone sees the transaction as completed */ for (cbp = *cbp_head; cbp; cbp = cbp->b_trans_next) { cbp->b_flags |= B_TDONE; } cbp = *cbp_head; if ((flags & (CL_ASYNC | CL_PAGEOUT)) == CL_PAGEOUT && vnode_isswap(cbp->b_vp)) { isswapout = TRUE; } error = cluster_iodone(cbp, callback_arg); if (!(flags & CL_ASYNC) && error && *retval == 0) { if (((flags & (CL_PAGEOUT | CL_KEEPCACHED)) != CL_PAGEOUT) || (error != ENXIO)) { *retval = error; } else if (isswapout == TRUE) { *retval = error; } } *cbp_head = (buf_t)NULL; } static int cluster_io(vnode_t vp, upl_t upl, vm_offset_t upl_offset, off_t f_offset, int non_rounded_size, int flags, buf_t real_bp, struct clios *iostate, int (*callback)(buf_t, void *), void *callback_arg) { buf_t cbp; u_int size; u_int io_size; int io_flags; int bmap_flags; int error = 0; int retval = 0; buf_t cbp_head = NULL; buf_t cbp_tail = NULL; int trans_count = 0; int max_trans_count; u_int pg_count; int pg_offset; u_int max_iosize; u_int max_vectors; int priv; int zero_offset = 0; int async_throttle = 0; mount_t mp; vm_offset_t upl_end_offset; boolean_t need_EOT = FALSE; size_t verify_block_size = 0; /* * we currently don't support buffers larger than a page */ if (real_bp && non_rounded_size > PAGE_SIZE) { panic("%s(): Called with real buffer of size %d bytes which " "is greater than the maximum allowed size of " "%d bytes (the system PAGE_SIZE).\n", __FUNCTION__, non_rounded_size, PAGE_SIZE); } mp = vp->v_mount; /* * we don't want to do any funny rounding of the size for IO requests * coming through the DIRECT or CONTIGUOUS paths... those pages don't * belong to us... we can't extend (nor do we need to) the I/O to fill * out a page */ if (mp->mnt_devblocksize > 1 && !(flags & (CL_DEV_MEMORY | CL_DIRECT_IO))) { /* * round the requested size up so that this I/O ends on a * page boundary in case this is a 'write'... if the filesystem * has blocks allocated to back the page beyond the EOF, we want to * make sure to write out the zero's that are sitting beyond the EOF * so that in case the filesystem doesn't explicitly zero this area * if a hole is created via a lseek/write beyond the current EOF, * it will return zeros when it's read back from the disk. If the * physical allocation doesn't extend for the whole page, we'll * only write/read from the disk up to the end of this allocation * via the extent info returned from the VNOP_BLOCKMAP call. */ pg_offset = upl_offset & PAGE_MASK; size = (((non_rounded_size + pg_offset) + (PAGE_SIZE - 1)) & ~PAGE_MASK) - pg_offset; } else { /* * anyone advertising a blocksize of 1 byte probably * can't deal with us rounding up the request size * AFP is one such filesystem/device */ size = non_rounded_size; } upl_end_offset = upl_offset + size; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 22)) | DBG_FUNC_START, (int)f_offset, size, upl_offset, flags, 0); /* * Set the maximum transaction size to the maximum desired number of * buffers. */ max_trans_count = 8; if (flags & CL_DEV_MEMORY) { max_trans_count = 16; } if (flags & CL_READ) { io_flags = B_READ; bmap_flags = VNODE_READ; max_iosize = mp->mnt_maxreadcnt; max_vectors = mp->mnt_segreadcnt; if ((flags & CL_PAGEIN) && /* Cluster layer verification will be limited to pagein for now */ !(mp->mnt_kern_flag & MNTK_VIRTUALDEV) && (VNOP_VERIFY(vp, f_offset, NULL, 0, &verify_block_size, NULL, VNODE_VERIFY_DEFAULT, NULL) == 0) && verify_block_size) { if (verify_block_size != PAGE_SIZE) { verify_block_size = 0; } if (real_bp && verify_block_size) { panic("%s(): Called with real buffer and needs verification ", __FUNCTION__); } } } else { io_flags = B_WRITE; bmap_flags = VNODE_WRITE; max_iosize = mp->mnt_maxwritecnt; max_vectors = mp->mnt_segwritecnt; } if (verify_block_size) { bmap_flags |= VNODE_CLUSTER_VERIFY; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 22)) | DBG_FUNC_NONE, max_iosize, max_vectors, mp->mnt_devblocksize, 0, 0); /* * make sure the maximum iosize is a * multiple of the page size */ max_iosize &= ~PAGE_MASK; /* * Ensure the maximum iosize is sensible. */ if (!max_iosize) { max_iosize = PAGE_SIZE; } if (flags & CL_THROTTLE) { if (!(flags & CL_PAGEOUT) && cluster_is_throttled(vp)) { uint32_t max_throttle_size = calculate_max_throttle_size(vp); if (max_iosize > max_throttle_size) { max_iosize = max_throttle_size; } async_throttle = calculate_max_throttle_cnt(vp); } else { if ((flags & CL_DEV_MEMORY)) { async_throttle = IO_SCALE(vp, VNODE_ASYNC_THROTTLE); } else { u_int max_cluster; u_int max_cluster_size; u_int scale; if (vp->v_mount->mnt_minsaturationbytecount) { max_cluster_size = vp->v_mount->mnt_minsaturationbytecount; scale = 1; } else { max_cluster_size = MAX_CLUSTER_SIZE(vp); if (disk_conditioner_mount_is_ssd(vp->v_mount)) { scale = WRITE_THROTTLE_SSD; } else { scale = WRITE_THROTTLE; } } if (max_iosize > max_cluster_size) { max_cluster = max_cluster_size; } else { max_cluster = max_iosize; } if (size < max_cluster) { max_cluster = size; } if (flags & CL_CLOSE) { scale += MAX_CLUSTERS; } async_throttle = min(IO_SCALE(vp, VNODE_ASYNC_THROTTLE), ((scale * max_cluster_size) / max_cluster) - 1); } } } if (flags & CL_AGE) { io_flags |= B_AGE; } if (flags & (CL_PAGEIN | CL_PAGEOUT)) { io_flags |= B_PAGEIO; } if (flags & (CL_IOSTREAMING)) { io_flags |= B_IOSTREAMING; } if (flags & CL_COMMIT) { io_flags |= B_COMMIT_UPL; } if (flags & CL_DIRECT_IO) { io_flags |= B_PHYS; } if (flags & (CL_PRESERVE | CL_KEEPCACHED)) { io_flags |= B_CACHE; } if (flags & CL_PASSIVE) { io_flags |= B_PASSIVE; } if (flags & CL_ENCRYPTED) { io_flags |= B_ENCRYPTED_IO; } if (vp->v_flag & VSYSTEM) { io_flags |= B_META; } if ((flags & CL_READ) && ((upl_offset + non_rounded_size) & PAGE_MASK) && (!(flags & CL_NOZERO))) { /* * then we are going to end up * with a page that we can't complete (the file size wasn't a multiple * of PAGE_SIZE and we're trying to read to the end of the file * so we'll go ahead and zero out the portion of the page we can't * read in from the file */ zero_offset = (int)(upl_offset + non_rounded_size); } else if (!ISSET(flags, CL_READ) && ISSET(flags, CL_DIRECT_IO)) { assert(ISSET(flags, CL_COMMIT)); // For a direct/uncached write, we need to lock pages... upl_t cached_upl; /* * Create a UPL to lock the pages in the cache whilst the * write is in progress. */ ubc_create_upl_kernel(vp, f_offset, non_rounded_size, &cached_upl, NULL, UPL_SET_LITE, VM_KERN_MEMORY_FILE); /* * Attach this UPL to the other UPL so that we can find it * later. */ upl_set_associated_upl(upl, cached_upl); if (upl_offset & PAGE_MASK) { /* * The two UPLs are not aligned, so mark the first page in * @upl so that cluster_handle_associated_upl can handle * it accordingly. */ upl_page_info_t *pl = UPL_GET_INTERNAL_PAGE_LIST(upl); upl_page_set_mark(pl, 0, true); } } while (size) { daddr64_t blkno; daddr64_t lblkno; size_t io_size_tmp; u_int io_size_wanted; uint32_t lblksize; if (size > max_iosize) { io_size = max_iosize; } else { io_size = size; } io_size_wanted = io_size; io_size_tmp = (size_t)io_size; if ((error = VNOP_BLOCKMAP(vp, f_offset, io_size, &blkno, &io_size_tmp, NULL, bmap_flags, NULL))) { break; } if (io_size_tmp > io_size_wanted) { io_size = io_size_wanted; } else { io_size = (u_int)io_size_tmp; } if (real_bp && (real_bp->b_blkno == real_bp->b_lblkno)) { real_bp->b_blkno = blkno; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 24)) | DBG_FUNC_NONE, (int)f_offset, (int)(blkno >> 32), (int)blkno, io_size, 0); if (io_size == 0) { /* * vnop_blockmap didn't return an error... however, it did * return an extent size of 0 which means we can't * make forward progress on this I/O... a hole in the * file would be returned as a blkno of -1 with a non-zero io_size * a real extent is returned with a blkno != -1 and a non-zero io_size */ error = EINVAL; break; } if (!(flags & CL_READ) && blkno == -1) { off_t e_offset; int pageout_flags; if (upl_get_internal_vectorupl(upl)) { panic("Vector UPLs should not take this code-path"); } /* * we're writing into a 'hole' */ if (flags & CL_PAGEOUT) { /* * if we got here via cluster_pageout * then just error the request and return * the 'hole' should already have been covered */ error = EINVAL; break; } /* * we can get here if the cluster code happens to * pick up a page that was dirtied via mmap vs * a 'write' and the page targets a 'hole'... * i.e. the writes to the cluster were sparse * and the file was being written for the first time * * we can also get here if the filesystem supports * 'holes' that are less than PAGE_SIZE.... because * we can't know if the range in the page that covers * the 'hole' has been dirtied via an mmap or not, * we have to assume the worst and try to push the * entire page to storage. * * Try paging out the page individually before * giving up entirely and dumping it (the pageout * path will insure that the zero extent accounting * has been taken care of before we get back into cluster_io) * * go direct to vnode_pageout so that we don't have to * unbusy the page from the UPL... we used to do this * so that we could call ubc_msync, but that results * in a potential deadlock if someone else races us to acquire * that page and wins and in addition needs one of the pages * we're continuing to hold in the UPL */ pageout_flags = UPL_MSYNC | UPL_VNODE_PAGER | UPL_NESTED_PAGEOUT; if (!(flags & CL_ASYNC)) { pageout_flags |= UPL_IOSYNC; } if (!(flags & CL_COMMIT)) { pageout_flags |= UPL_NOCOMMIT; } if (cbp_head) { buf_t prev_cbp; uint32_t bytes_in_last_page; /* * first we have to wait for the the current outstanding I/Os * to complete... EOT hasn't been set yet on this transaction * so the pages won't be released */ cluster_wait_IO(cbp_head, (flags & CL_ASYNC)); bytes_in_last_page = cbp_head->b_uploffset & PAGE_MASK; for (cbp = cbp_head; cbp; cbp = cbp->b_trans_next) { bytes_in_last_page += cbp->b_bcount; } bytes_in_last_page &= PAGE_MASK; while (bytes_in_last_page) { /* * we've got a transcation that * includes the page we're about to push out through vnode_pageout... * find the bp's in the list which intersect this page and either * remove them entirely from the transaction (there could be multiple bp's), or * round it's iosize down to the page boundary (there can only be one)... * * find the last bp in the list and act on it */ for (prev_cbp = cbp = cbp_head; cbp->b_trans_next; cbp = cbp->b_trans_next) { prev_cbp = cbp; } if (bytes_in_last_page >= cbp->b_bcount) { /* * this buf no longer has any I/O associated with it */ bytes_in_last_page -= cbp->b_bcount; cbp->b_bcount = 0; free_io_buf(cbp); if (cbp == cbp_head) { assert(bytes_in_last_page == 0); /* * the buf we just freed was the only buf in * this transaction... so there's no I/O to do */ cbp_head = NULL; cbp_tail = NULL; } else { /* * remove the buf we just freed from * the transaction list */ prev_cbp->b_trans_next = NULL; cbp_tail = prev_cbp; } } else { /* * this is the last bp that has I/O * intersecting the page of interest * only some of the I/O is in the intersection * so clip the size but keep it in the transaction list */ cbp->b_bcount -= bytes_in_last_page; cbp_tail = cbp; bytes_in_last_page = 0; } } if (cbp_head) { /* * there was more to the current transaction * than just the page we are pushing out via vnode_pageout... * mark it as finished and complete it... we've already * waited for the I/Os to complete above in the call to cluster_wait_IO */ cluster_EOT(cbp_head, cbp_tail, 0, 0); cluster_complete_transaction(&cbp_head, callback_arg, &retval, flags, 0); trans_count = 0; } } if (vnode_pageout(vp, upl, (upl_offset_t)trunc_page(upl_offset), trunc_page_64(f_offset), PAGE_SIZE, pageout_flags, NULL) != PAGER_SUCCESS) { error = EINVAL; } e_offset = round_page_64(f_offset + 1); io_size = (u_int)(e_offset - f_offset); f_offset += io_size; upl_offset += io_size; if (size >= io_size) { size -= io_size; } else { size = 0; } /* * keep track of how much of the original request * that we've actually completed... non_rounded_size * may go negative due to us rounding the request * to a page size multiple (i.e. size > non_rounded_size) */ non_rounded_size -= io_size; if (non_rounded_size <= 0) { /* * we've transferred all of the data in the original * request, but we were unable to complete the tail * of the last page because the file didn't have * an allocation to back that portion... this is ok. */ size = 0; } if (error) { if (size == 0) { flags &= ~CL_COMMIT; } break; } continue; } lblksize = CLUSTER_IO_BLOCK_SIZE; lblkno = (daddr64_t)(f_offset / lblksize); /* * we have now figured out how much I/O we can do - this is in 'io_size' * pg_offset is the starting point in the first page for the I/O * pg_count is the number of full and partial pages that 'io_size' encompasses */ pg_offset = upl_offset & PAGE_MASK; if (flags & CL_DEV_MEMORY) { /* * treat physical requests as one 'giant' page */ pg_count = 1; } else { pg_count = (io_size + pg_offset + (PAGE_SIZE - 1)) / PAGE_SIZE; } if ((flags & CL_READ) && blkno == -1) { vm_offset_t commit_offset; int bytes_to_zero; int complete_transaction_now = 0; /* * if we're reading and blkno == -1, then we've got a * 'hole' in the file that we need to deal with by zeroing * out the affected area in the upl */ if (io_size >= (u_int)non_rounded_size) { /* * if this upl contains the EOF and it is not a multiple of PAGE_SIZE * than 'zero_offset' will be non-zero * if the 'hole' returned by vnop_blockmap extends all the way to the eof * (indicated by the io_size finishing off the I/O request for this UPL) * than we're not going to issue an I/O for the * last page in this upl... we need to zero both the hole and the tail * of the page beyond the EOF, since the delayed zero-fill won't kick in */ bytes_to_zero = non_rounded_size; if (!(flags & CL_NOZERO)) { bytes_to_zero = (int)((((upl_offset + io_size) + (PAGE_SIZE - 1)) & ~PAGE_MASK) - upl_offset); } zero_offset = 0; } else { bytes_to_zero = io_size; } pg_count = 0; cluster_zero(upl, (upl_offset_t)upl_offset, bytes_to_zero, real_bp); if (cbp_head) { int pg_resid; /* * if there is a current I/O chain pending * then the first page of the group we just zero'd * will be handled by the I/O completion if the zero * fill started in the middle of the page */ commit_offset = (upl_offset + (PAGE_SIZE - 1)) & ~PAGE_MASK; pg_resid = (int)(commit_offset - upl_offset); if (bytes_to_zero >= pg_resid) { /* * the last page of the current I/O * has been completed... * compute the number of fully zero'd * pages that are beyond it * plus the last page if its partial * and we have no more I/O to issue... * otherwise a partial page is left * to begin the next I/O */ if ((int)io_size >= non_rounded_size) { pg_count = (bytes_to_zero - pg_resid + (PAGE_SIZE - 1)) / PAGE_SIZE; } else { pg_count = (bytes_to_zero - pg_resid) / PAGE_SIZE; } complete_transaction_now = 1; } } else { /* * no pending I/O to deal with * so, commit all of the fully zero'd pages * plus the last page if its partial * and we have no more I/O to issue... * otherwise a partial page is left * to begin the next I/O */ if ((int)io_size >= non_rounded_size) { pg_count = (pg_offset + bytes_to_zero + (PAGE_SIZE - 1)) / PAGE_SIZE; } else { pg_count = (pg_offset + bytes_to_zero) / PAGE_SIZE; } commit_offset = upl_offset & ~PAGE_MASK; } // Associated UPL is currently only used in the direct write path assert(!upl_associated_upl(upl)); if ((flags & CL_COMMIT) && pg_count) { ubc_upl_commit_range(upl, (upl_offset_t)commit_offset, pg_count * PAGE_SIZE, UPL_COMMIT_CLEAR_DIRTY | UPL_COMMIT_FREE_ON_EMPTY); } upl_offset += io_size; f_offset += io_size; size -= io_size; /* * keep track of how much of the original request * that we've actually completed... non_rounded_size * may go negative due to us rounding the request * to a page size multiple (i.e. size > non_rounded_size) */ non_rounded_size -= io_size; if (non_rounded_size <= 0) { /* * we've transferred all of the data in the original * request, but we were unable to complete the tail * of the last page because the file didn't have * an allocation to back that portion... this is ok. */ size = 0; } if (cbp_head && (complete_transaction_now || size == 0)) { cluster_wait_IO(cbp_head, (flags & CL_ASYNC)); cluster_EOT(cbp_head, cbp_tail, size == 0 ? zero_offset : 0, verify_block_size); cluster_complete_transaction(&cbp_head, callback_arg, &retval, flags, 0); trans_count = 0; } continue; } if (pg_count > max_vectors) { if (((pg_count - max_vectors) * PAGE_SIZE) > io_size) { io_size = PAGE_SIZE - pg_offset; pg_count = 1; } else { io_size -= (pg_count - max_vectors) * PAGE_SIZE; pg_count = max_vectors; } } /* * If the transaction is going to reach the maximum number of * desired elements, truncate the i/o to the nearest page so * that the actual i/o is initiated after this buffer is * created and added to the i/o chain. * * I/O directed to physically contiguous memory * doesn't have a requirement to make sure we 'fill' a page */ if (!(flags & CL_DEV_MEMORY) && trans_count >= max_trans_count && ((upl_offset + io_size) & PAGE_MASK)) { vm_offset_t aligned_ofs; aligned_ofs = (upl_offset + io_size) & ~PAGE_MASK; /* * If the io_size does not actually finish off even a * single page we have to keep adding buffers to the * transaction despite having reached the desired limit. * * Eventually we get here with the page being finished * off (and exceeded) and then we truncate the size of * this i/o request so that it is page aligned so that * we can finally issue the i/o on the transaction. */ if (aligned_ofs > upl_offset) { io_size = (u_int)(aligned_ofs - upl_offset); pg_count--; } } if (!(mp->mnt_kern_flag & MNTK_VIRTUALDEV)) { /* * if we're not targeting a virtual device i.e. a disk image * it's safe to dip into the reserve pool since real devices * can complete this I/O request without requiring additional * bufs from the alloc_io_buf pool */ priv = 1; } else if ((flags & CL_ASYNC) && !(flags & CL_PAGEOUT) && !cbp_head) { /* * Throttle the speculative IO * * We can only throttle this if it is the first iobuf * for the transaction. alloc_io_buf implements * additional restrictions for diskimages anyway. */ priv = 0; } else { priv = 1; } cbp = alloc_io_buf(vp, priv); if (flags & CL_PAGEOUT) { u_int i; /* * since blocks are in offsets of lblksize (CLUSTER_IO_BLOCK_SIZE), scale * iteration to (PAGE_SIZE * pg_count) of blks. */ for (i = 0; i < (PAGE_SIZE * pg_count) / lblksize; i++) { if (buf_invalblkno(vp, lblkno + i, 0) == EBUSY) { panic("BUSY bp found in cluster_io"); } } } if (flags & CL_ASYNC) { if (buf_setcallback(cbp, (void *)cluster_iodone, callback_arg)) { panic("buf_setcallback failed"); } } cbp->b_cliodone = (void *)callback; cbp->b_flags |= io_flags; if (flags & CL_NOCACHE) { cbp->b_attr.ba_flags |= BA_NOCACHE; } if (verify_block_size) { cbp->b_attr.ba_flags |= BA_WILL_VERIFY; } cbp->b_lblkno = lblkno; cbp->b_lblksize = lblksize; cbp->b_blkno = blkno; cbp->b_bcount = io_size; if (buf_setupl(cbp, upl, (uint32_t)upl_offset)) { panic("buf_setupl failed"); } #if CONFIG_IOSCHED upl_set_blkno(upl, upl_offset, io_size, blkno); #endif cbp->b_trans_next = (buf_t)NULL; if ((cbp->b_iostate = (void *)iostate)) { /* * caller wants to track the state of this * io... bump the amount issued against this stream */ iostate->io_issued += io_size; } if (flags & CL_READ) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 26)) | DBG_FUNC_NONE, (int)cbp->b_lblkno, (int)cbp->b_blkno, upl_offset, io_size, 0); } else { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 27)) | DBG_FUNC_NONE, (int)cbp->b_lblkno, (int)cbp->b_blkno, upl_offset, io_size, 0); } if (cbp_head) { cbp_tail->b_trans_next = cbp; cbp_tail = cbp; } else { cbp_head = cbp; cbp_tail = cbp; if ((cbp_head->b_real_bp = real_bp)) { real_bp = (buf_t)NULL; } } *(buf_t *)(&cbp->b_trans_head) = cbp_head; trans_count++; upl_offset += io_size; f_offset += io_size; size -= io_size; /* * keep track of how much of the original request * that we've actually completed... non_rounded_size * may go negative due to us rounding the request * to a page size multiple (i.e. size > non_rounded_size) */ non_rounded_size -= io_size; if (non_rounded_size <= 0) { /* * we've transferred all of the data in the original * request, but we were unable to complete the tail * of the last page because the file didn't have * an allocation to back that portion... this is ok. */ size = 0; } if (size == 0) { /* * we have no more I/O to issue, so go * finish the final transaction */ need_EOT = TRUE; } else if (((flags & CL_DEV_MEMORY) || (upl_offset & PAGE_MASK) == 0) && ((flags & CL_ASYNC) || trans_count > max_trans_count)) { /* * I/O directed to physically contiguous memory... * which doesn't have a requirement to make sure we 'fill' a page * or... * the current I/O we've prepared fully * completes the last page in this request * and ... * it's either an ASYNC request or * we've already accumulated more than 8 I/O's into * this transaction so mark it as complete so that * it can finish asynchronously or via the cluster_complete_transaction * below if the request is synchronous */ need_EOT = TRUE; } if (need_EOT == TRUE) { cluster_EOT(cbp_head, cbp_tail, size == 0 ? zero_offset : 0, verify_block_size); } if (flags & CL_THROTTLE) { (void)vnode_waitforwrites(vp, async_throttle, 0, 0, "cluster_io"); } if (!(io_flags & B_READ)) { vnode_startwrite(vp); } if (flags & CL_RAW_ENCRYPTED) { /* * User requested raw encrypted bytes. * Twiddle the bit in the ba_flags for the buffer */ cbp->b_attr.ba_flags |= BA_RAW_ENCRYPTED_IO; } (void) VNOP_STRATEGY(cbp); if (need_EOT == TRUE) { if (!(flags & CL_ASYNC)) { cluster_complete_transaction(&cbp_head, callback_arg, &retval, flags, 1); } need_EOT = FALSE; trans_count = 0; cbp_head = NULL; } } if (error) { int abort_size; io_size = 0; if (cbp_head) { /* * Wait until all of the outstanding I/O * for this partial transaction has completed */ cluster_wait_IO(cbp_head, (flags & CL_ASYNC)); /* * Rewind the upl offset to the beginning of the * transaction. */ upl_offset = cbp_head->b_uploffset; } if (ISSET(flags, CL_COMMIT)) { cluster_handle_associated_upl(iostate, upl, (upl_offset_t)upl_offset, (upl_size_t)(upl_end_offset - upl_offset)); } // Free all the IO buffers in this transaction for (cbp = cbp_head; cbp;) { buf_t cbp_next; size += cbp->b_bcount; io_size += cbp->b_bcount; cbp_next = cbp->b_trans_next; free_io_buf(cbp); cbp = cbp_next; } if (iostate) { int need_wakeup = 0; /* * update the error condition for this stream * since we never really issued the io * just go ahead and adjust it back */ lck_mtx_lock_spin(&iostate->io_mtxp); if (iostate->io_error == 0) { iostate->io_error = error; } iostate->io_issued -= io_size; if (iostate->io_wanted) { /* * someone is waiting for the state of * this io stream to change */ iostate->io_wanted = 0; need_wakeup = 1; } lck_mtx_unlock(&iostate->io_mtxp); if (need_wakeup) { wakeup((caddr_t)&iostate->io_wanted); } } if (flags & CL_COMMIT) { int upl_flags; pg_offset = upl_offset & PAGE_MASK; abort_size = (int)((upl_end_offset - upl_offset + PAGE_MASK) & ~PAGE_MASK); upl_flags = cluster_ioerror(upl, (int)(upl_offset - pg_offset), abort_size, error, io_flags, vp); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 28)) | DBG_FUNC_NONE, upl, upl_offset - pg_offset, abort_size, (error << 24) | upl_flags, 0); } if (retval == 0) { retval = error; } } else if (cbp_head) { panic("%s(): cbp_head is not NULL.", __FUNCTION__); } if (real_bp) { /* * can get here if we either encountered an error * or we completely zero-filled the request and * no I/O was issued */ if (error) { real_bp->b_flags |= B_ERROR; real_bp->b_error = error; } buf_biodone(real_bp); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 22)) | DBG_FUNC_END, (int)f_offset, size, upl_offset, retval, 0); return retval; } #define reset_vector_run_state() \ issueVectorUPL = vector_upl_offset = vector_upl_index = vector_upl_iosize = vector_upl_size = 0; static int vector_cluster_io(vnode_t vp, upl_t vector_upl, vm_offset_t vector_upl_offset, off_t v_upl_uio_offset, int vector_upl_iosize, int io_flag, buf_t real_bp, struct clios *iostate, int (*callback)(buf_t, void *), void *callback_arg) { vector_upl_set_pagelist(vector_upl); if (io_flag & CL_READ) { if (vector_upl_offset == 0 && ((vector_upl_iosize & PAGE_MASK) == 0)) { io_flag &= ~CL_PRESERVE; /*don't zero fill*/ } else { io_flag |= CL_PRESERVE; /*zero fill*/ } } return cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, real_bp, iostate, callback, callback_arg); } static int cluster_read_prefetch(vnode_t vp, off_t f_offset, u_int size, off_t filesize, int (*callback)(buf_t, void *), void *callback_arg, int bflag) { int pages_in_prefetch; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 49)) | DBG_FUNC_START, (int)f_offset, size, (int)filesize, 0, 0); if (f_offset >= filesize) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 49)) | DBG_FUNC_END, (int)f_offset, 0, 0, 0, 0); return 0; } if ((off_t)size > (filesize - f_offset)) { size = (u_int)(filesize - f_offset); } pages_in_prefetch = (size + (PAGE_SIZE - 1)) / PAGE_SIZE; advisory_read_ext(vp, filesize, f_offset, size, callback, callback_arg, bflag); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 49)) | DBG_FUNC_END, (int)f_offset + size, pages_in_prefetch, 0, 1, 0); return pages_in_prefetch; } static void cluster_read_ahead(vnode_t vp, struct cl_extent *extent, off_t filesize, struct cl_readahead *rap, int (*callback)(buf_t, void *), void *callback_arg, int bflag) { daddr64_t r_addr; off_t f_offset; int size_of_prefetch; u_int max_prefetch; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_START, (int)extent->b_addr, (int)extent->e_addr, (int)rap->cl_lastr, 0, 0); if (extent->b_addr == rap->cl_lastr && extent->b_addr == extent->e_addr) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 0, 0); return; } if (rap->cl_lastr == -1 || (extent->b_addr != rap->cl_lastr && extent->b_addr != (rap->cl_lastr + 1))) { rap->cl_ralen = 0; rap->cl_maxra = 0; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 1, 0); return; } max_prefetch = cluster_max_prefetch(vp, cluster_max_io_size(vp->v_mount, CL_READ), speculative_prefetch_max); if (max_prefetch <= PAGE_SIZE) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 6, 0); return; } if (extent->e_addr < rap->cl_maxra && rap->cl_ralen >= 4) { if ((rap->cl_maxra - extent->e_addr) > (rap->cl_ralen / 4)) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 2, 0); return; } } r_addr = MAX(extent->e_addr, rap->cl_maxra) + 1; f_offset = (off_t)(r_addr * PAGE_SIZE_64); size_of_prefetch = 0; ubc_range_op(vp, f_offset, f_offset + PAGE_SIZE_64, UPL_ROP_PRESENT, &size_of_prefetch); if (size_of_prefetch) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 3, 0); return; } if (f_offset < filesize) { daddr64_t read_size; rap->cl_ralen = rap->cl_ralen ? min(max_prefetch / PAGE_SIZE, rap->cl_ralen << 1) : 1; read_size = (extent->e_addr + 1) - extent->b_addr; if (read_size > rap->cl_ralen) { if (read_size > max_prefetch / PAGE_SIZE) { rap->cl_ralen = max_prefetch / PAGE_SIZE; } else { rap->cl_ralen = (int)read_size; } } size_of_prefetch = cluster_read_prefetch(vp, f_offset, rap->cl_ralen * PAGE_SIZE, filesize, callback, callback_arg, bflag); if (size_of_prefetch) { rap->cl_maxra = (r_addr + size_of_prefetch) - 1; } } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 48)) | DBG_FUNC_END, rap->cl_ralen, (int)rap->cl_maxra, (int)rap->cl_lastr, 4, 0); } int cluster_pageout(vnode_t vp, upl_t upl, upl_offset_t upl_offset, off_t f_offset, int size, off_t filesize, int flags) { return cluster_pageout_ext(vp, upl, upl_offset, f_offset, size, filesize, flags, NULL, NULL); } int cluster_pageout_ext(vnode_t vp, upl_t upl, upl_offset_t upl_offset, off_t f_offset, int size, off_t filesize, int flags, int (*callback)(buf_t, void *), void *callback_arg) { int io_size; int rounded_size; off_t max_size; int local_flags; local_flags = CL_PAGEOUT | CL_THROTTLE; if ((flags & UPL_IOSYNC) == 0) { local_flags |= CL_ASYNC; } if ((flags & UPL_NOCOMMIT) == 0) { local_flags |= CL_COMMIT; } if ((flags & UPL_KEEPCACHED)) { local_flags |= CL_KEEPCACHED; } if (flags & UPL_PAGING_ENCRYPTED) { local_flags |= CL_ENCRYPTED; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 52)) | DBG_FUNC_NONE, (int)f_offset, size, (int)filesize, local_flags, 0); /* * If they didn't specify any I/O, then we are done... * we can't issue an abort because we don't know how * big the upl really is */ if (size <= 0) { return EINVAL; } if (vp->v_mount->mnt_flag & MNT_RDONLY) { if (local_flags & CL_COMMIT) { ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY); } return EROFS; } /* * can't page-in from a negative offset * or if we're starting beyond the EOF * or if the file offset isn't page aligned * or the size requested isn't a multiple of PAGE_SIZE */ if (f_offset < 0 || f_offset >= filesize || (f_offset & PAGE_MASK_64) || (size & PAGE_MASK)) { if (local_flags & CL_COMMIT) { ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY); } return EINVAL; } max_size = filesize - f_offset; if (size < max_size) { io_size = size; } else { io_size = (int)max_size; } rounded_size = (io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if (size > rounded_size) { if (local_flags & CL_COMMIT) { ubc_upl_abort_range(upl, upl_offset + rounded_size, size - rounded_size, UPL_ABORT_FREE_ON_EMPTY); } } return cluster_io(vp, upl, upl_offset, f_offset, io_size, local_flags, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); } int cluster_pagein(vnode_t vp, upl_t upl, upl_offset_t upl_offset, off_t f_offset, int size, off_t filesize, int flags) { return cluster_pagein_ext(vp, upl, upl_offset, f_offset, size, filesize, flags, NULL, NULL); } int cluster_pagein_ext(vnode_t vp, upl_t upl, upl_offset_t upl_offset, off_t f_offset, int size, off_t filesize, int flags, int (*callback)(buf_t, void *), void *callback_arg) { u_int io_size; int rounded_size; off_t max_size; int retval; int local_flags = 0; if (upl == NULL || size < 0) { panic("cluster_pagein: NULL upl passed in"); } if ((flags & UPL_IOSYNC) == 0) { local_flags |= CL_ASYNC; } if ((flags & UPL_NOCOMMIT) == 0) { local_flags |= CL_COMMIT; } if (flags & UPL_IOSTREAMING) { local_flags |= CL_IOSTREAMING; } if (flags & UPL_PAGING_ENCRYPTED) { local_flags |= CL_ENCRYPTED; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 56)) | DBG_FUNC_NONE, (int)f_offset, size, (int)filesize, local_flags, 0); /* * can't page-in from a negative offset * or if we're starting beyond the EOF * or if the file offset isn't page aligned * or the size requested isn't a multiple of PAGE_SIZE */ if (f_offset < 0 || f_offset >= filesize || (f_offset & PAGE_MASK_64) || (size & PAGE_MASK) || (upl_offset & PAGE_MASK)) { if (local_flags & CL_COMMIT) { ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_ERROR); } if (f_offset >= filesize) { ktriage_record(thread_tid(current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_CLUSTER, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_CL_PGIN_PAST_EOF), 0 /* arg */); } return EINVAL; } max_size = filesize - f_offset; if (size < max_size) { io_size = size; } else { io_size = (int)max_size; } rounded_size = (io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if (size > rounded_size && (local_flags & CL_COMMIT)) { ubc_upl_abort_range(upl, upl_offset + rounded_size, size - rounded_size, UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_ERROR); } retval = cluster_io(vp, upl, upl_offset, f_offset, io_size, local_flags | CL_READ | CL_PAGEIN, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); return retval; } int cluster_bp(buf_t bp) { return cluster_bp_ext(bp, NULL, NULL); } int cluster_bp_ext(buf_t bp, int (*callback)(buf_t, void *), void *callback_arg) { off_t f_offset; int flags; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 19)) | DBG_FUNC_START, bp, (int)bp->b_lblkno, bp->b_bcount, bp->b_flags, 0); if (bp->b_flags & B_READ) { flags = CL_ASYNC | CL_READ; } else { flags = CL_ASYNC; } if (bp->b_flags & B_PASSIVE) { flags |= CL_PASSIVE; } f_offset = ubc_blktooff(bp->b_vp, bp->b_lblkno); return cluster_io(bp->b_vp, bp->b_upl, 0, f_offset, bp->b_bcount, flags, bp, (struct clios *)NULL, callback, callback_arg); } int cluster_write(vnode_t vp, struct uio *uio, off_t oldEOF, off_t newEOF, off_t headOff, off_t tailOff, int xflags) { return cluster_write_ext(vp, uio, oldEOF, newEOF, headOff, tailOff, xflags, NULL, NULL); } int cluster_write_ext(vnode_t vp, struct uio *uio, off_t oldEOF, off_t newEOF, off_t headOff, off_t tailOff, int xflags, int (*callback)(buf_t, void *), void *callback_arg) { user_ssize_t cur_resid; int retval = 0; int flags; int zflags; int bflag; int write_type = IO_COPY; u_int32_t write_length; flags = xflags; if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (vp->v_flag & VNOCACHE_DATA) { flags |= IO_NOCACHE; bflag |= CL_NOCACHE; } if (uio == NULL) { /* * no user data... * this call is being made to zero-fill some range in the file */ retval = cluster_write_copy(vp, NULL, (u_int32_t)0, oldEOF, newEOF, headOff, tailOff, flags, callback, callback_arg); return retval; } /* * do a write through the cache if one of the following is true.... * NOCACHE is not true or NODIRECT is true * the uio request doesn't target USERSPACE * otherwise, find out if we want the direct or contig variant for * the first vector in the uio request */ if (((flags & (IO_NOCACHE | IO_NODIRECT)) == IO_NOCACHE) && UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) { retval = cluster_io_type(uio, &write_type, &write_length, MIN_DIRECT_WRITE_SIZE); } if ((flags & (IO_TAILZEROFILL | IO_HEADZEROFILL)) && write_type == IO_DIRECT) { /* * must go through the cached variant in this case */ write_type = IO_COPY; } while ((cur_resid = uio_resid(uio)) && uio->uio_offset < newEOF && retval == 0) { switch (write_type) { case IO_COPY: /* * make sure the uio_resid isn't too big... * internally, we want to handle all of the I/O in * chunk sizes that fit in a 32 bit int */ if (cur_resid > (user_ssize_t)(MAX_IO_REQUEST_SIZE)) { /* * we're going to have to call cluster_write_copy * more than once... * * only want the last call to cluster_write_copy to * have the IO_TAILZEROFILL flag set and only the * first call should have IO_HEADZEROFILL */ zflags = flags & ~IO_TAILZEROFILL; flags &= ~IO_HEADZEROFILL; write_length = MAX_IO_REQUEST_SIZE; } else { /* * last call to cluster_write_copy */ zflags = flags; write_length = (u_int32_t)cur_resid; } retval = cluster_write_copy(vp, uio, write_length, oldEOF, newEOF, headOff, tailOff, zflags, callback, callback_arg); break; case IO_CONTIG: zflags = flags & ~(IO_TAILZEROFILL | IO_HEADZEROFILL); if (flags & IO_HEADZEROFILL) { /* * only do this once per request */ flags &= ~IO_HEADZEROFILL; retval = cluster_write_copy(vp, (struct uio *)0, (u_int32_t)0, (off_t)0, uio->uio_offset, headOff, (off_t)0, zflags | IO_HEADZEROFILL | IO_SYNC, callback, callback_arg); if (retval) { break; } } retval = cluster_write_contig(vp, uio, newEOF, &write_type, &write_length, callback, callback_arg, bflag); if (retval == 0 && (flags & IO_TAILZEROFILL) && uio_resid(uio) == 0) { /* * we're done with the data from the user specified buffer(s) * and we've been requested to zero fill at the tail * treat this as an IO_HEADZEROFILL which doesn't require a uio * by rearranging the args and passing in IO_HEADZEROFILL */ /* * Update the oldEOF to reflect the current EOF. If the UPL page * to zero-fill is not valid (when F_NOCACHE is set), the * cluster_write_copy() will perform RMW on the UPL page when * the oldEOF is not aligned on page boundary due to unaligned * write. */ if (uio->uio_offset > oldEOF) { oldEOF = uio->uio_offset; } retval = cluster_write_copy(vp, (struct uio *)0, (u_int32_t)0, (off_t)oldEOF, tailOff, uio->uio_offset, (off_t)0, zflags | IO_HEADZEROFILL | IO_SYNC, callback, callback_arg); } break; case IO_DIRECT: /* * cluster_write_direct is never called with IO_TAILZEROFILL || IO_HEADZEROFILL */ retval = cluster_write_direct(vp, uio, oldEOF, newEOF, &write_type, &write_length, flags, callback, callback_arg); break; case IO_UNKNOWN: retval = cluster_io_type(uio, &write_type, &write_length, MIN_DIRECT_WRITE_SIZE); break; } /* * in case we end up calling cluster_write_copy (from cluster_write_direct) * multiple times to service a multi-vector request that is not aligned properly * we need to update the oldEOF so that we * don't zero-fill the head of a page if we've successfully written * data to that area... 'cluster_write_copy' will zero-fill the head of a * page that is beyond the oldEOF if the write is unaligned... we only * want that to happen for the very first page of the cluster_write, * NOT the first page of each vector making up a multi-vector write. */ if (uio->uio_offset > oldEOF) { oldEOF = uio->uio_offset; } } return retval; } static int cluster_write_direct(vnode_t vp, struct uio *uio, off_t oldEOF, off_t newEOF, int *write_type, u_int32_t *write_length, int flags, int (*callback)(buf_t, void *), void *callback_arg) { upl_t upl = NULL; upl_page_info_t *pl; vm_offset_t upl_offset; vm_offset_t vector_upl_offset = 0; u_int32_t io_req_size; u_int32_t offset_in_file; u_int32_t offset_in_iovbase; u_int32_t io_size; int io_flag = 0; upl_size_t upl_size = 0, vector_upl_size = 0; vm_size_t upl_needed_size; mach_msg_type_number_t pages_in_pl = 0; upl_control_flags_t upl_flags; kern_return_t kret = KERN_SUCCESS; mach_msg_type_number_t i = 0; int force_data_sync; int retval = 0; int first_IO = 1; struct clios iostate; user_addr_t iov_base; u_int32_t mem_alignment_mask; u_int32_t devblocksize; u_int32_t max_io_size; u_int32_t max_upl_size; u_int32_t max_vector_size; u_int32_t bytes_outstanding_limit; boolean_t io_throttled = FALSE; u_int32_t vector_upl_iosize = 0; int issueVectorUPL = 0, useVectorUPL = (uio->uio_iovcnt > 1); off_t v_upl_uio_offset = 0; int vector_upl_index = 0; upl_t vector_upl = NULL; /* * When we enter this routine, we know * -- the resid will not exceed iov_len */ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 75)) | DBG_FUNC_START, (int)uio->uio_offset, *write_length, (int)newEOF, 0, 0); assert(vm_map_page_shift(current_map()) >= PAGE_SHIFT); max_upl_size = cluster_max_io_size(vp->v_mount, CL_WRITE); io_flag = CL_ASYNC | CL_PRESERVE | CL_COMMIT | CL_THROTTLE | CL_DIRECT_IO; if (flags & IO_PASSIVE) { io_flag |= CL_PASSIVE; } if (flags & IO_NOCACHE) { io_flag |= CL_NOCACHE; } if (flags & IO_SKIP_ENCRYPTION) { io_flag |= CL_ENCRYPTED; } iostate.io_completed = 0; iostate.io_issued = 0; iostate.io_error = 0; iostate.io_wanted = 0; lck_mtx_init(&iostate.io_mtxp, &cl_mtx_grp, LCK_ATTR_NULL); mem_alignment_mask = (u_int32_t)vp->v_mount->mnt_alignmentmask; devblocksize = (u_int32_t)vp->v_mount->mnt_devblocksize; if (devblocksize == 1) { /* * the AFP client advertises a devblocksize of 1 * however, its BLOCKMAP routine maps to physical * blocks that are PAGE_SIZE in size... * therefore we can't ask for I/Os that aren't page aligned * or aren't multiples of PAGE_SIZE in size * by setting devblocksize to PAGE_SIZE, we re-instate * the old behavior we had before the mem_alignment_mask * changes went in... */ devblocksize = PAGE_SIZE; } next_dwrite: io_req_size = *write_length; iov_base = uio_curriovbase(uio); offset_in_file = (u_int32_t)uio->uio_offset & PAGE_MASK; offset_in_iovbase = (u_int32_t)iov_base & mem_alignment_mask; if (offset_in_file || offset_in_iovbase) { /* * one of the 2 important offsets is misaligned * so fire an I/O through the cache for this entire vector */ goto wait_for_dwrites; } if (iov_base & (devblocksize - 1)) { /* * the offset in memory must be on a device block boundary * so that we can guarantee that we can generate an * I/O that ends on a page boundary in cluster_io */ goto wait_for_dwrites; } task_update_logical_writes(current_task(), (io_req_size & ~PAGE_MASK), TASK_WRITE_IMMEDIATE, vp); while (io_req_size >= PAGE_SIZE && uio->uio_offset < newEOF && retval == 0) { int throttle_type; if ((throttle_type = cluster_is_throttled(vp))) { uint32_t max_throttle_size = calculate_max_throttle_size(vp); /* * we're in the throttle window, at the very least * we want to limit the size of the I/O we're about * to issue */ if ((flags & IO_RETURN_ON_THROTTLE) && throttle_type == THROTTLE_NOW) { /* * we're in the throttle window and at least 1 I/O * has already been issued by a throttleable thread * in this window, so return with EAGAIN to indicate * to the FS issuing the cluster_write call that it * should now throttle after dropping any locks */ throttle_info_update_by_mount(vp->v_mount); io_throttled = TRUE; goto wait_for_dwrites; } max_vector_size = max_throttle_size; max_io_size = max_throttle_size; } else { max_vector_size = MAX_VECTOR_UPL_SIZE; max_io_size = max_upl_size; } if (first_IO) { cluster_syncup(vp, newEOF, callback, callback_arg, callback ? PUSH_SYNC : 0); first_IO = 0; } io_size = io_req_size & ~PAGE_MASK; iov_base = uio_curriovbase(uio); if (io_size > max_io_size) { io_size = max_io_size; } if (useVectorUPL && (iov_base & PAGE_MASK)) { /* * We have an iov_base that's not page-aligned. * Issue all I/O's that have been collected within * this Vectored UPL. */ if (vector_upl_index) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } /* * After this point, if we are using the Vector UPL path and the base is * not page-aligned then the UPL with that base will be the first in the vector UPL. */ } upl_offset = (vm_offset_t)((u_int32_t)iov_base & PAGE_MASK); upl_needed_size = (upl_offset + io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 76)) | DBG_FUNC_START, (int)upl_offset, upl_needed_size, (int)iov_base, io_size, 0); vm_map_t map = UIO_SEG_IS_USER_SPACE(uio->uio_segflg) ? current_map() : kernel_map; for (force_data_sync = 0; force_data_sync < 3; force_data_sync++) { pages_in_pl = 0; upl_size = (upl_size_t)upl_needed_size; upl_flags = UPL_FILE_IO | UPL_COPYOUT_FROM | UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | UPL_SET_INTERNAL | UPL_SET_LITE | UPL_SET_IO_WIRE; kret = vm_map_get_upl(map, (vm_map_offset_t)(iov_base & ~((user_addr_t)PAGE_MASK)), &upl_size, &upl, NULL, &pages_in_pl, &upl_flags, VM_KERN_MEMORY_FILE, force_data_sync); if (kret != KERN_SUCCESS) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 76)) | DBG_FUNC_END, 0, 0, 0, kret, 0); /* * failed to get pagelist * * we may have already spun some portion of this request * off as async requests... we need to wait for the I/O * to complete before returning */ goto wait_for_dwrites; } pl = UPL_GET_INTERNAL_PAGE_LIST(upl); pages_in_pl = upl_size / PAGE_SIZE; for (i = 0; i < pages_in_pl; i++) { if (!upl_valid_page(pl, i)) { break; } } if (i == pages_in_pl) { break; } /* * didn't get all the pages back that we * needed... release this upl and try again */ ubc_upl_abort(upl, 0); } if (force_data_sync >= 3) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 76)) | DBG_FUNC_END, i, pages_in_pl, upl_size, kret, 0); /* * for some reason, we couldn't acquire a hold on all * the pages needed in the user's address space * * we may have already spun some portion of this request * off as async requests... we need to wait for the I/O * to complete before returning */ goto wait_for_dwrites; } /* * Consider the possibility that upl_size wasn't satisfied. */ if (upl_size < upl_needed_size) { if (upl_size && upl_offset == 0) { io_size = upl_size; } else { io_size = 0; } } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 76)) | DBG_FUNC_END, (int)upl_offset, upl_size, (int)iov_base, io_size, 0); if (io_size == 0) { ubc_upl_abort(upl, 0); /* * we may have already spun some portion of this request * off as async requests... we need to wait for the I/O * to complete before returning */ goto wait_for_dwrites; } if (useVectorUPL) { vm_offset_t end_off = ((iov_base + io_size) & PAGE_MASK); if (end_off) { issueVectorUPL = 1; } /* * After this point, if we are using a vector UPL, then * either all the UPL elements end on a page boundary OR * this UPL is the last element because it does not end * on a page boundary. */ } /* * we want push out these writes asynchronously so that we can overlap * the preparation of the next I/O * if there are already too many outstanding writes * wait until some complete before issuing the next */ if (vp->v_mount->mnt_minsaturationbytecount) { bytes_outstanding_limit = vp->v_mount->mnt_minsaturationbytecount; } else { if (__improbable(os_mul_overflow(max_upl_size, IO_SCALE(vp, 2), &bytes_outstanding_limit) || (bytes_outstanding_limit > overlapping_write_max))) { bytes_outstanding_limit = overlapping_write_max; } } cluster_iostate_wait(&iostate, bytes_outstanding_limit, "cluster_write_direct"); if (iostate.io_error) { /* * one of the earlier writes we issued ran into a hard error * don't issue any more writes, cleanup the UPL * that was just created but not used, then * go wait for all writes that are part of this stream * to complete before returning the error to the caller */ ubc_upl_abort(upl, 0); goto wait_for_dwrites; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 77)) | DBG_FUNC_START, (int)upl_offset, (int)uio->uio_offset, io_size, io_flag, 0); if (!useVectorUPL) { retval = cluster_io(vp, upl, upl_offset, uio->uio_offset, io_size, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); } else { if (!vector_upl_index) { vector_upl = vector_upl_create(upl_offset, uio->uio_iovcnt); v_upl_uio_offset = uio->uio_offset; vector_upl_offset = upl_offset; } vector_upl_set_subupl(vector_upl, upl, upl_size); vector_upl_set_iostate(vector_upl, upl, vector_upl_size, upl_size); vector_upl_index++; vector_upl_iosize += io_size; vector_upl_size += upl_size; if (issueVectorUPL || vector_upl_index == vector_upl_max_upls(vector_upl) || vector_upl_size >= max_vector_size) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } } /* * update the uio structure to * reflect the I/O that we just issued */ uio_update(uio, (user_size_t)io_size); /* * in case we end up calling through to cluster_write_copy to finish * the tail of this request, we need to update the oldEOF so that we * don't zero-fill the head of a page if we've successfully written * data to that area... 'cluster_write_copy' will zero-fill the head of a * page that is beyond the oldEOF if the write is unaligned... we only * want that to happen for the very first page of the cluster_write, * NOT the first page of each vector making up a multi-vector write. */ if (uio->uio_offset > oldEOF) { oldEOF = uio->uio_offset; } io_req_size -= io_size; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 77)) | DBG_FUNC_END, (int)upl_offset, (int)uio->uio_offset, io_req_size, retval, 0); } /* end while */ if (retval == 0 && iostate.io_error == 0 && io_req_size == 0) { retval = cluster_io_type(uio, write_type, write_length, MIN_DIRECT_WRITE_SIZE); if (retval == 0 && *write_type == IO_DIRECT) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 75)) | DBG_FUNC_NONE, (int)uio->uio_offset, *write_length, (int)newEOF, 0, 0); goto next_dwrite; } } wait_for_dwrites: if (retval == 0 && iostate.io_error == 0 && useVectorUPL && vector_upl_index) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } /* * make sure all async writes issued as part of this stream * have completed before we return */ cluster_iostate_wait(&iostate, 0, "cluster_write_direct"); if (iostate.io_error) { retval = iostate.io_error; } lck_mtx_destroy(&iostate.io_mtxp, &cl_mtx_grp); if (io_throttled == TRUE && retval == 0) { retval = EAGAIN; } if (io_req_size && retval == 0) { /* * we couldn't handle the tail of this request in DIRECT mode * so fire it through the copy path * * note that flags will never have IO_HEADZEROFILL or IO_TAILZEROFILL set * so we can just pass 0 in for the headOff and tailOff */ if (uio->uio_offset > oldEOF) { oldEOF = uio->uio_offset; } retval = cluster_write_copy(vp, uio, io_req_size, oldEOF, newEOF, (off_t)0, (off_t)0, flags, callback, callback_arg); *write_type = IO_UNKNOWN; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 75)) | DBG_FUNC_END, (int)uio->uio_offset, io_req_size, retval, 4, 0); return retval; } static int cluster_write_contig(vnode_t vp, struct uio *uio, off_t newEOF, int *write_type, u_int32_t *write_length, int (*callback)(buf_t, void *), void *callback_arg, int bflag) { upl_page_info_t *pl; addr64_t src_paddr = 0; upl_t upl[MAX_VECTS]; vm_offset_t upl_offset; u_int32_t tail_size = 0; u_int32_t io_size; u_int32_t xsize; upl_size_t upl_size; vm_size_t upl_needed_size; mach_msg_type_number_t pages_in_pl; upl_control_flags_t upl_flags; kern_return_t kret; struct clios iostate; int error = 0; int cur_upl = 0; int num_upl = 0; int n; user_addr_t iov_base; u_int32_t devblocksize; u_int32_t mem_alignment_mask; /* * When we enter this routine, we know * -- the io_req_size will not exceed iov_len * -- the target address is physically contiguous */ cluster_syncup(vp, newEOF, callback, callback_arg, callback ? PUSH_SYNC : 0); devblocksize = (u_int32_t)vp->v_mount->mnt_devblocksize; mem_alignment_mask = (u_int32_t)vp->v_mount->mnt_alignmentmask; iostate.io_completed = 0; iostate.io_issued = 0; iostate.io_error = 0; iostate.io_wanted = 0; lck_mtx_init(&iostate.io_mtxp, &cl_mtx_grp, LCK_ATTR_NULL); next_cwrite: io_size = *write_length; iov_base = uio_curriovbase(uio); upl_offset = (vm_offset_t)((u_int32_t)iov_base & PAGE_MASK); upl_needed_size = upl_offset + io_size; pages_in_pl = 0; upl_size = (upl_size_t)upl_needed_size; upl_flags = UPL_FILE_IO | UPL_COPYOUT_FROM | UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | UPL_SET_INTERNAL | UPL_SET_LITE | UPL_SET_IO_WIRE; vm_map_t map = UIO_SEG_IS_USER_SPACE(uio->uio_segflg) ? current_map() : kernel_map; kret = vm_map_get_upl(map, vm_map_trunc_page(iov_base, vm_map_page_mask(map)), &upl_size, &upl[cur_upl], NULL, &pages_in_pl, &upl_flags, VM_KERN_MEMORY_FILE, 0); if (kret != KERN_SUCCESS) { /* * failed to get pagelist */ error = EINVAL; goto wait_for_cwrites; } num_upl++; /* * Consider the possibility that upl_size wasn't satisfied. */ if (upl_size < upl_needed_size) { /* * This is a failure in the physical memory case. */ error = EINVAL; goto wait_for_cwrites; } pl = ubc_upl_pageinfo(upl[cur_upl]); src_paddr = ((addr64_t)upl_phys_page(pl, 0) << PAGE_SHIFT) + (addr64_t)upl_offset; while (((uio->uio_offset & (devblocksize - 1)) || io_size < devblocksize) && io_size) { u_int32_t head_size; head_size = devblocksize - (u_int32_t)(uio->uio_offset & (devblocksize - 1)); if (head_size > io_size) { head_size = io_size; } error = cluster_align_phys_io(vp, uio, src_paddr, head_size, 0, callback, callback_arg); if (error) { goto wait_for_cwrites; } upl_offset += head_size; src_paddr += head_size; io_size -= head_size; iov_base += head_size; } if ((u_int32_t)iov_base & mem_alignment_mask) { /* * request doesn't set up on a memory boundary * the underlying DMA engine can handle... * return an error instead of going through * the slow copy path since the intent of this * path is direct I/O from device memory */ error = EINVAL; goto wait_for_cwrites; } tail_size = io_size & (devblocksize - 1); io_size -= tail_size; while (io_size && error == 0) { if (io_size > MAX_IO_CONTIG_SIZE) { xsize = MAX_IO_CONTIG_SIZE; } else { xsize = io_size; } /* * request asynchronously so that we can overlap * the preparation of the next I/O... we'll do * the commit after all the I/O has completed * since its all issued against the same UPL * if there are already too many outstanding writes * wait until some have completed before issuing the next */ cluster_iostate_wait(&iostate, MAX_IO_CONTIG_SIZE * IO_SCALE(vp, 2), "cluster_write_contig"); if (iostate.io_error) { /* * one of the earlier writes we issued ran into a hard error * don't issue any more writes... * go wait for all writes that are part of this stream * to complete before returning the error to the caller */ goto wait_for_cwrites; } /* * issue an asynchronous write to cluster_io */ error = cluster_io(vp, upl[cur_upl], upl_offset, uio->uio_offset, xsize, CL_DEV_MEMORY | CL_ASYNC | bflag, (buf_t)NULL, (struct clios *)&iostate, callback, callback_arg); if (error == 0) { /* * The cluster_io write completed successfully, * update the uio structure */ uio_update(uio, (user_size_t)xsize); upl_offset += xsize; src_paddr += xsize; io_size -= xsize; } } if (error == 0 && iostate.io_error == 0 && tail_size == 0 && num_upl < MAX_VECTS) { error = cluster_io_type(uio, write_type, write_length, 0); if (error == 0 && *write_type == IO_CONTIG) { cur_upl++; goto next_cwrite; } } else { *write_type = IO_UNKNOWN; } wait_for_cwrites: /* * make sure all async writes that are part of this stream * have completed before we proceed */ cluster_iostate_wait(&iostate, 0, "cluster_write_contig"); if (iostate.io_error) { error = iostate.io_error; } lck_mtx_destroy(&iostate.io_mtxp, &cl_mtx_grp); if (error == 0 && tail_size) { error = cluster_align_phys_io(vp, uio, src_paddr, tail_size, 0, callback, callback_arg); } for (n = 0; n < num_upl; n++) { /* * just release our hold on each physically contiguous * region without changing any state */ ubc_upl_abort(upl[n], 0); } return error; } /* * need to avoid a race between an msync of a range of pages dirtied via mmap * vs a filesystem such as HFS deciding to write a 'hole' to disk via cluster_write's * zerofill mechanism before it has seen the VNOP_PAGEOUTs for the pages being msync'd * * we should never force-zero-fill pages that are already valid in the cache... * the entire page contains valid data (either from disk, zero-filled or dirtied * via an mmap) so we can only do damage by trying to zero-fill * */ static int cluster_zero_range(upl_t upl, upl_page_info_t *pl, int flags, int io_offset, off_t zero_off, off_t upl_f_offset, int bytes_to_zero) { int zero_pg_index; boolean_t need_cluster_zero = TRUE; if ((flags & (IO_NOZEROVALID | IO_NOZERODIRTY))) { bytes_to_zero = min(bytes_to_zero, PAGE_SIZE - (int)(zero_off & PAGE_MASK_64)); zero_pg_index = (int)((zero_off - upl_f_offset) / PAGE_SIZE_64); if (upl_valid_page(pl, zero_pg_index)) { /* * never force zero valid pages - dirty or clean * we'll leave these in the UPL for cluster_write_copy to deal with */ need_cluster_zero = FALSE; } } if (need_cluster_zero == TRUE) { cluster_zero(upl, io_offset, bytes_to_zero, NULL); } return bytes_to_zero; } void cluster_update_state(vnode_t vp, vm_object_offset_t s_offset, vm_object_offset_t e_offset, boolean_t vm_initiated) { struct cl_extent cl; boolean_t first_pass = TRUE; assert(s_offset < e_offset); assert((s_offset & PAGE_MASK_64) == 0); assert((e_offset & PAGE_MASK_64) == 0); cl.b_addr = (daddr64_t)(s_offset / PAGE_SIZE_64); cl.e_addr = (daddr64_t)(e_offset / PAGE_SIZE_64); cluster_update_state_internal(vp, &cl, 0, TRUE, &first_pass, s_offset, (int)(e_offset - s_offset), vp->v_un.vu_ubcinfo->ui_size, NULL, NULL, vm_initiated); } static void cluster_update_state_internal(vnode_t vp, struct cl_extent *cl, int flags, boolean_t defer_writes, boolean_t *first_pass, off_t write_off, int write_cnt, off_t newEOF, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated) { struct cl_writebehind *wbp; int cl_index; int ret_cluster_try_push; u_int max_cluster_pgcount; max_cluster_pgcount = MAX_CLUSTER_SIZE(vp) / PAGE_SIZE; /* * take the lock to protect our accesses * of the writebehind and sparse cluster state */ wbp = cluster_get_wbp(vp, CLW_ALLOCATE | CLW_RETURNLOCKED); if (wbp->cl_scmap) { if (!(flags & IO_NOCACHE)) { /* * we've fallen into the sparse * cluster method of delaying dirty pages */ sparse_cluster_add(wbp, &(wbp->cl_scmap), vp, cl, newEOF, callback, callback_arg, vm_initiated); lck_mtx_unlock(&wbp->cl_lockw); return; } /* * must have done cached writes that fell into * the sparse cluster mechanism... we've switched * to uncached writes on the file, so go ahead * and push whatever's in the sparse map * and switch back to normal clustering */ wbp->cl_number = 0; sparse_cluster_push(wbp, &(wbp->cl_scmap), vp, newEOF, PUSH_ALL, 0, callback, callback_arg, vm_initiated); /* * no clusters of either type present at this point * so just go directly to start_new_cluster since * we know we need to delay this I/O since we've * already released the pages back into the cache * to avoid the deadlock with sparse_cluster_push */ goto start_new_cluster; } if (*first_pass == TRUE) { if (write_off == wbp->cl_last_write) { wbp->cl_seq_written += write_cnt; } else { wbp->cl_seq_written = write_cnt; } wbp->cl_last_write = write_off + write_cnt; *first_pass = FALSE; } if (wbp->cl_number == 0) { /* * no clusters currently present */ goto start_new_cluster; } for (cl_index = 0; cl_index < wbp->cl_number; cl_index++) { /* * check each cluster that we currently hold * try to merge some or all of this write into * one or more of the existing clusters... if * any portion of the write remains, start a * new cluster */ if (cl->b_addr >= wbp->cl_clusters[cl_index].b_addr) { /* * the current write starts at or after the current cluster */ if (cl->e_addr <= (wbp->cl_clusters[cl_index].b_addr + max_cluster_pgcount)) { /* * we have a write that fits entirely * within the existing cluster limits */ if (cl->e_addr > wbp->cl_clusters[cl_index].e_addr) { /* * update our idea of where the cluster ends */ wbp->cl_clusters[cl_index].e_addr = cl->e_addr; } break; } if (cl->b_addr < (wbp->cl_clusters[cl_index].b_addr + max_cluster_pgcount)) { /* * we have a write that starts in the middle of the current cluster * but extends beyond the cluster's limit... we know this because * of the previous checks * we'll extend the current cluster to the max * and update the b_addr for the current write to reflect that * the head of it was absorbed into this cluster... * note that we'll always have a leftover tail in this case since * full absorbtion would have occurred in the clause above */ wbp->cl_clusters[cl_index].e_addr = wbp->cl_clusters[cl_index].b_addr + max_cluster_pgcount; cl->b_addr = wbp->cl_clusters[cl_index].e_addr; } /* * we come here for the case where the current write starts * beyond the limit of the existing cluster or we have a leftover * tail after a partial absorbtion * * in either case, we'll check the remaining clusters before * starting a new one */ } else { /* * the current write starts in front of the cluster we're currently considering */ if ((wbp->cl_clusters[cl_index].e_addr - cl->b_addr) <= max_cluster_pgcount) { /* * we can just merge the new request into * this cluster and leave it in the cache * since the resulting cluster is still * less than the maximum allowable size */ wbp->cl_clusters[cl_index].b_addr = cl->b_addr; if (cl->e_addr > wbp->cl_clusters[cl_index].e_addr) { /* * the current write completely * envelops the existing cluster and since * each write is limited to at most max_cluster_pgcount pages * we can just use the start and last blocknos of the write * to generate the cluster limits */ wbp->cl_clusters[cl_index].e_addr = cl->e_addr; } break; } /* * if we were to combine this write with the current cluster * we would exceed the cluster size limit.... so, * let's see if there's any overlap of the new I/O with * the cluster we're currently considering... in fact, we'll * stretch the cluster out to it's full limit and see if we * get an intersection with the current write * */ if (cl->e_addr > wbp->cl_clusters[cl_index].e_addr - max_cluster_pgcount) { /* * the current write extends into the proposed cluster * clip the length of the current write after first combining it's * tail with the newly shaped cluster */ wbp->cl_clusters[cl_index].b_addr = wbp->cl_clusters[cl_index].e_addr - max_cluster_pgcount; cl->e_addr = wbp->cl_clusters[cl_index].b_addr; } /* * if we get here, there was no way to merge * any portion of this write with this cluster * or we could only merge part of it which * will leave a tail... * we'll check the remaining clusters before starting a new one */ } } if (cl_index < wbp->cl_number) { /* * we found an existing cluster(s) that we * could entirely merge this I/O into */ goto delay_io; } if (defer_writes == FALSE && wbp->cl_number == MAX_CLUSTERS && wbp->cl_seq_written >= (MAX_CLUSTERS * (max_cluster_pgcount * PAGE_SIZE))) { uint32_t n; if (vp->v_mount->mnt_minsaturationbytecount) { n = vp->v_mount->mnt_minsaturationbytecount / MAX_CLUSTER_SIZE(vp); if (n > MAX_CLUSTERS) { n = MAX_CLUSTERS; } } else { n = 0; } if (n == 0) { if (disk_conditioner_mount_is_ssd(vp->v_mount)) { n = WRITE_BEHIND_SSD; } else { n = WRITE_BEHIND; } } while (n--) { cluster_try_push(wbp, vp, newEOF, 0, 0, callback, callback_arg, NULL, vm_initiated); } } if (wbp->cl_number < MAX_CLUSTERS) { /* * we didn't find an existing cluster to * merge into, but there's room to start * a new one */ goto start_new_cluster; } /* * no exisitng cluster to merge with and no * room to start a new one... we'll try * pushing one of the existing ones... if none of * them are able to be pushed, we'll switch * to the sparse cluster mechanism * cluster_try_push updates cl_number to the * number of remaining clusters... and * returns the number of currently unused clusters */ ret_cluster_try_push = 0; /* * if writes are not deferred, call cluster push immediately */ if (defer_writes == FALSE) { ret_cluster_try_push = cluster_try_push(wbp, vp, newEOF, (flags & IO_NOCACHE) ? 0 : PUSH_DELAY, 0, callback, callback_arg, NULL, vm_initiated); } /* * execute following regardless of writes being deferred or not */ if (ret_cluster_try_push == 0) { /* * no more room in the normal cluster mechanism * so let's switch to the more expansive but expensive * sparse mechanism.... */ sparse_cluster_switch(wbp, vp, newEOF, callback, callback_arg, vm_initiated); sparse_cluster_add(wbp, &(wbp->cl_scmap), vp, cl, newEOF, callback, callback_arg, vm_initiated); lck_mtx_unlock(&wbp->cl_lockw); return; } start_new_cluster: wbp->cl_clusters[wbp->cl_number].b_addr = cl->b_addr; wbp->cl_clusters[wbp->cl_number].e_addr = cl->e_addr; wbp->cl_clusters[wbp->cl_number].io_flags = 0; if (flags & IO_NOCACHE) { wbp->cl_clusters[wbp->cl_number].io_flags |= CLW_IONOCACHE; } if (flags & IO_PASSIVE) { wbp->cl_clusters[wbp->cl_number].io_flags |= CLW_IOPASSIVE; } wbp->cl_number++; delay_io: lck_mtx_unlock(&wbp->cl_lockw); return; } static int cluster_write_copy(vnode_t vp, struct uio *uio, u_int32_t io_req_size, off_t oldEOF, off_t newEOF, off_t headOff, off_t tailOff, int flags, int (*callback)(buf_t, void *), void *callback_arg) { upl_page_info_t *pl; upl_t upl; vm_offset_t upl_offset = 0; vm_size_t upl_size; off_t upl_f_offset; int pages_in_upl; int start_offset; int xfer_resid; int io_size; int io_offset; int bytes_to_zero; int bytes_to_move; kern_return_t kret; int retval = 0; int io_resid; long long total_size; long long zero_cnt; off_t zero_off; long long zero_cnt1; off_t zero_off1; off_t write_off = 0; int write_cnt = 0; boolean_t first_pass = FALSE; struct cl_extent cl; int bflag; u_int max_io_size; if (uio) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 40)) | DBG_FUNC_START, (int)uio->uio_offset, io_req_size, (int)oldEOF, (int)newEOF, 0); io_resid = io_req_size; } else { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 40)) | DBG_FUNC_START, 0, 0, (int)oldEOF, (int)newEOF, 0); io_resid = 0; } if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (flags & IO_NOCACHE) { bflag |= CL_NOCACHE; } if (flags & IO_SKIP_ENCRYPTION) { bflag |= CL_ENCRYPTED; } zero_cnt = 0; zero_cnt1 = 0; zero_off = 0; zero_off1 = 0; max_io_size = cluster_max_io_size(vp->v_mount, CL_WRITE); if (flags & IO_HEADZEROFILL) { /* * some filesystems (HFS is one) don't support unallocated holes within a file... * so we zero fill the intervening space between the old EOF and the offset * where the next chunk of real data begins.... ftruncate will also use this * routine to zero fill to the new EOF when growing a file... in this case, the * uio structure will not be provided */ if (uio) { if (headOff < uio->uio_offset) { zero_cnt = uio->uio_offset - headOff; zero_off = headOff; } } else if (headOff < newEOF) { zero_cnt = newEOF - headOff; zero_off = headOff; } } else { if (uio && uio->uio_offset > oldEOF) { zero_off = uio->uio_offset & ~PAGE_MASK_64; if (zero_off >= oldEOF) { zero_cnt = uio->uio_offset - zero_off; flags |= IO_HEADZEROFILL; } } } if (flags & IO_TAILZEROFILL) { if (uio) { zero_off1 = uio->uio_offset + io_req_size; if (zero_off1 < tailOff) { zero_cnt1 = tailOff - zero_off1; } } } else { if (uio && newEOF > oldEOF) { zero_off1 = uio->uio_offset + io_req_size; if (zero_off1 == newEOF && (zero_off1 & PAGE_MASK_64)) { zero_cnt1 = PAGE_SIZE_64 - (zero_off1 & PAGE_MASK_64); flags |= IO_TAILZEROFILL; } } } if (zero_cnt == 0 && uio == (struct uio *) 0) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 40)) | DBG_FUNC_END, retval, 0, 0, 0, 0); return 0; } if (uio) { write_off = uio->uio_offset; write_cnt = (int)uio_resid(uio); /* * delay updating the sequential write info * in the control block until we've obtained * the lock for it */ first_pass = TRUE; } while ((total_size = (io_resid + zero_cnt + zero_cnt1)) && retval == 0) { /* * for this iteration of the loop, figure out where our starting point is */ if (zero_cnt) { start_offset = (int)(zero_off & PAGE_MASK_64); upl_f_offset = zero_off - start_offset; } else if (io_resid) { start_offset = (int)(uio->uio_offset & PAGE_MASK_64); upl_f_offset = uio->uio_offset - start_offset; } else { start_offset = (int)(zero_off1 & PAGE_MASK_64); upl_f_offset = zero_off1 - start_offset; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 46)) | DBG_FUNC_NONE, (int)zero_off, (int)zero_cnt, (int)zero_off1, (int)zero_cnt1, 0); if (total_size > max_io_size) { total_size = max_io_size; } cl.b_addr = (daddr64_t)(upl_f_offset / PAGE_SIZE_64); if (uio && ((flags & (IO_SYNC | IO_HEADZEROFILL | IO_TAILZEROFILL)) == 0)) { /* * assumption... total_size <= io_resid * because IO_HEADZEROFILL and IO_TAILZEROFILL not set */ if ((start_offset + total_size) > max_io_size) { total_size = max_io_size - start_offset; } xfer_resid = (int)total_size; retval = cluster_copy_ubc_data_internal(vp, uio, &xfer_resid, 1, 1); if (retval) { break; } io_resid -= (total_size - xfer_resid); total_size = xfer_resid; start_offset = (int)(uio->uio_offset & PAGE_MASK_64); upl_f_offset = uio->uio_offset - start_offset; if (total_size == 0) { if (start_offset) { /* * the write did not finish on a page boundary * which will leave upl_f_offset pointing to the * beginning of the last page written instead of * the page beyond it... bump it in this case * so that the cluster code records the last page * written as dirty */ upl_f_offset += PAGE_SIZE_64; } upl_size = 0; goto check_cluster; } } /* * compute the size of the upl needed to encompass * the requested write... limit each call to cluster_io * to the maximum UPL size... cluster_io will clip if * this exceeds the maximum io_size for the device, * make sure to account for * a starting offset that's not page aligned */ upl_size = (start_offset + total_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if (upl_size > max_io_size) { upl_size = max_io_size; } pages_in_upl = (int)(upl_size / PAGE_SIZE); io_size = (int)(upl_size - start_offset); if ((long long)io_size > total_size) { io_size = (int)total_size; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 41)) | DBG_FUNC_START, upl_size, io_size, total_size, 0, 0); /* * Gather the pages from the buffer cache. * The UPL_WILL_MODIFY flag lets the UPL subsystem know * that we intend to modify these pages. */ kret = ubc_create_upl_kernel(vp, upl_f_offset, (int)upl_size, &upl, &pl, UPL_SET_LITE | ((uio != NULL && (uio->uio_flags & UIO_FLAGS_IS_COMPRESSED_FILE)) ? 0 : UPL_WILL_MODIFY), VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { panic("cluster_write_copy: failed to get pagelist"); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 41)) | DBG_FUNC_END, upl, (int)upl_f_offset, start_offset, 0, 0); if (start_offset && upl_f_offset < oldEOF && !upl_valid_page(pl, 0)) { int read_size; /* * we're starting in the middle of the first page of the upl * and the page isn't currently valid, so we're going to have * to read it in first... this is a synchronous operation */ read_size = PAGE_SIZE; if ((upl_f_offset + read_size) > oldEOF) { read_size = (int)(oldEOF - upl_f_offset); } retval = cluster_io(vp, upl, 0, upl_f_offset, read_size, CL_READ | bflag, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); if (retval) { /* * we had an error during the read which causes us to abort * the current cluster_write request... before we do, we need * to release the rest of the pages in the upl without modifying * there state and mark the failed page in error */ ubc_upl_abort_range(upl, 0, PAGE_SIZE, UPL_ABORT_DUMP_PAGES | UPL_ABORT_FREE_ON_EMPTY); if (upl_size > PAGE_SIZE) { ubc_upl_abort_range(upl, 0, (upl_size_t)upl_size, UPL_ABORT_FREE_ON_EMPTY); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 45)) | DBG_FUNC_NONE, upl, 0, 0, retval, 0); break; } } if ((start_offset == 0 || upl_size > PAGE_SIZE) && ((start_offset + io_size) & PAGE_MASK)) { /* * the last offset we're writing to in this upl does not end on a page * boundary... if it's not beyond the old EOF, then we'll also need to * pre-read this page in if it isn't already valid */ upl_offset = upl_size - PAGE_SIZE; if ((upl_f_offset + start_offset + io_size) < oldEOF && !upl_valid_page(pl, (int)(upl_offset / PAGE_SIZE))) { int read_size; read_size = PAGE_SIZE; if ((off_t)(upl_f_offset + upl_offset + read_size) > oldEOF) { read_size = (int)(oldEOF - (upl_f_offset + upl_offset)); } retval = cluster_io(vp, upl, upl_offset, upl_f_offset + upl_offset, read_size, CL_READ | bflag, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); if (retval) { /* * we had an error during the read which causes us to abort * the current cluster_write request... before we do, we * need to release the rest of the pages in the upl without * modifying there state and mark the failed page in error */ ubc_upl_abort_range(upl, (upl_offset_t)upl_offset, PAGE_SIZE, UPL_ABORT_DUMP_PAGES | UPL_ABORT_FREE_ON_EMPTY); if (upl_size > PAGE_SIZE) { ubc_upl_abort_range(upl, 0, (upl_size_t)upl_size, UPL_ABORT_FREE_ON_EMPTY); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 45)) | DBG_FUNC_NONE, upl, 0, 0, retval, 0); break; } } } xfer_resid = io_size; io_offset = start_offset; while (zero_cnt && xfer_resid) { if (zero_cnt < (long long)xfer_resid) { bytes_to_zero = (int)zero_cnt; } else { bytes_to_zero = xfer_resid; } bytes_to_zero = cluster_zero_range(upl, pl, flags, io_offset, zero_off, upl_f_offset, bytes_to_zero); xfer_resid -= bytes_to_zero; zero_cnt -= bytes_to_zero; zero_off += bytes_to_zero; io_offset += bytes_to_zero; } if (xfer_resid && io_resid) { u_int32_t io_requested; bytes_to_move = min(io_resid, xfer_resid); io_requested = bytes_to_move; retval = cluster_copy_upl_data(uio, upl, io_offset, (int *)&io_requested); if (retval) { ubc_upl_abort_range(upl, 0, (upl_size_t)upl_size, UPL_ABORT_FREE_ON_EMPTY); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 45)) | DBG_FUNC_NONE, upl, 0, 0, retval, 0); } else { io_resid -= bytes_to_move; xfer_resid -= bytes_to_move; io_offset += bytes_to_move; } } while (xfer_resid && zero_cnt1 && retval == 0) { if (zero_cnt1 < (long long)xfer_resid) { bytes_to_zero = (int)zero_cnt1; } else { bytes_to_zero = xfer_resid; } bytes_to_zero = cluster_zero_range(upl, pl, flags, io_offset, zero_off1, upl_f_offset, bytes_to_zero); xfer_resid -= bytes_to_zero; zero_cnt1 -= bytes_to_zero; zero_off1 += bytes_to_zero; io_offset += bytes_to_zero; } if (retval == 0) { int do_zeroing = 1; io_size += start_offset; /* Force more restrictive zeroing behavior only on APFS */ if ((vnode_tag(vp) == VT_APFS) && (newEOF < oldEOF)) { do_zeroing = 0; } if (do_zeroing && (upl_f_offset + io_size) >= newEOF && (u_int)io_size < upl_size) { /* * if we're extending the file with this write * we'll zero fill the rest of the page so that * if the file gets extended again in such a way as to leave a * hole starting at this EOF, we'll have zero's in the correct spot */ cluster_zero(upl, io_size, (int)(upl_size - io_size), NULL); } /* * release the upl now if we hold one since... * 1) pages in it may be present in the sparse cluster map * and may span 2 separate buckets there... if they do and * we happen to have to flush a bucket to make room and it intersects * this upl, a deadlock may result on page BUSY * 2) we're delaying the I/O... from this point forward we're just updating * the cluster state... no need to hold the pages, so commit them * 3) IO_SYNC is set... * because we had to ask for a UPL that provides currenty non-present pages, the * UPL has been automatically set to clear the dirty flags (both software and hardware) * upon committing it... this is not the behavior we want since it's possible for * pages currently present as part of a mapped file to be dirtied while the I/O is in flight. * we'll pick these pages back up later with the correct behavior specified. * 4) we don't want to hold pages busy in a UPL and then block on the cluster lock... if a flush * of this vnode is in progress, we will deadlock if the pages being flushed intersect the pages * we hold since the flushing context is holding the cluster lock. */ ubc_upl_commit_range(upl, 0, (upl_size_t)upl_size, UPL_COMMIT_SET_DIRTY | UPL_COMMIT_INACTIVATE | UPL_COMMIT_FREE_ON_EMPTY); check_cluster: /* * calculate the last logical block number * that this delayed I/O encompassed */ cl.e_addr = (daddr64_t)((upl_f_offset + (off_t)upl_size) / PAGE_SIZE_64); if (flags & IO_SYNC) { /* * if the IO_SYNC flag is set than we need to bypass * any clustering and immediately issue the I/O * * we don't hold the lock at this point * * we've already dropped the current upl, so pick it back up with COPYOUT_FROM set * so that we correctly deal with a change in state of the hardware modify bit... * we do this via cluster_push_now... by passing along the IO_SYNC flag, we force * cluster_push_now to wait until all the I/Os have completed... cluster_push_now is also * responsible for generating the correct sized I/O(s) */ retval = cluster_push_now(vp, &cl, newEOF, flags, callback, callback_arg, FALSE); } else { boolean_t defer_writes = FALSE; if (vfs_flags(vp->v_mount) & MNT_DEFWRITE) { defer_writes = TRUE; } cluster_update_state_internal(vp, &cl, flags, defer_writes, &first_pass, write_off, write_cnt, newEOF, callback, callback_arg, FALSE); } } } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 40)) | DBG_FUNC_END, retval, 0, io_resid, 0, 0); return retval; } int cluster_read(vnode_t vp, struct uio *uio, off_t filesize, int xflags) { return cluster_read_ext(vp, uio, filesize, xflags, NULL, NULL); } int cluster_read_ext(vnode_t vp, struct uio *uio, off_t filesize, int xflags, int (*callback)(buf_t, void *), void *callback_arg) { int retval = 0; int flags; user_ssize_t cur_resid; u_int32_t io_size; u_int32_t read_length = 0; int read_type = IO_COPY; flags = xflags; if (vp->v_flag & VNOCACHE_DATA) { flags |= IO_NOCACHE; } if ((vp->v_flag & VRAOFF) || speculative_reads_disabled) { flags |= IO_RAOFF; } if (flags & IO_SKIP_ENCRYPTION) { flags |= IO_ENCRYPTED; } /* * do a read through the cache if one of the following is true.... * NOCACHE is not true * the uio request doesn't target USERSPACE * Alternatively, if IO_ENCRYPTED is set, then we want to bypass the cache as well. * Reading encrypted data from a CP filesystem should never result in the data touching * the UBC. * * otherwise, find out if we want the direct or contig variant for * the first vector in the uio request */ if (((flags & IO_NOCACHE) && UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) || (flags & IO_ENCRYPTED)) { retval = cluster_io_type(uio, &read_type, &read_length, 0); } while ((cur_resid = uio_resid(uio)) && uio->uio_offset < filesize && retval == 0) { switch (read_type) { case IO_COPY: /* * make sure the uio_resid isn't too big... * internally, we want to handle all of the I/O in * chunk sizes that fit in a 32 bit int */ if (cur_resid > (user_ssize_t)(MAX_IO_REQUEST_SIZE)) { io_size = MAX_IO_REQUEST_SIZE; } else { io_size = (u_int32_t)cur_resid; } retval = cluster_read_copy(vp, uio, io_size, filesize, flags, callback, callback_arg); break; case IO_DIRECT: retval = cluster_read_direct(vp, uio, filesize, &read_type, &read_length, flags, callback, callback_arg); break; case IO_CONTIG: retval = cluster_read_contig(vp, uio, filesize, &read_type, &read_length, callback, callback_arg, flags); break; case IO_UNKNOWN: retval = cluster_io_type(uio, &read_type, &read_length, 0); break; } } return retval; } static void cluster_read_upl_release(upl_t upl, int start_pg, int last_pg, int take_reference) { int range; int abort_flags = UPL_ABORT_FREE_ON_EMPTY; if ((range = last_pg - start_pg)) { if (take_reference) { abort_flags |= UPL_ABORT_REFERENCE; } ubc_upl_abort_range(upl, start_pg * PAGE_SIZE, range * PAGE_SIZE, abort_flags); } } static int cluster_read_copy(vnode_t vp, struct uio *uio, u_int32_t io_req_size, off_t filesize, int flags, int (*callback)(buf_t, void *), void *callback_arg) { upl_page_info_t *pl; upl_t upl = NULL; vm_offset_t upl_offset; u_int32_t upl_size; off_t upl_f_offset; int start_offset; int start_pg; int last_pg; int uio_last = 0; int pages_in_upl; off_t max_size; off_t last_ioread_offset; off_t last_request_offset; kern_return_t kret; int error = 0; int retval = 0; u_int32_t size_of_prefetch; u_int32_t xsize; u_int32_t io_size; u_int32_t max_rd_size; u_int32_t max_io_size; u_int32_t max_prefetch; u_int rd_ahead_enabled = 1; u_int prefetch_enabled = 1; struct cl_readahead * rap; struct clios iostate; struct cl_extent extent; int bflag; int take_reference = 1; int policy = IOPOL_DEFAULT; boolean_t iolock_inited = FALSE; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 32)) | DBG_FUNC_START, (int)uio->uio_offset, io_req_size, (int)filesize, flags, 0); if (flags & IO_ENCRYPTED) { panic("encrypted blocks will hit UBC!"); } policy = throttle_get_io_policy(NULL); if (policy == THROTTLE_LEVEL_TIER3 || policy == THROTTLE_LEVEL_TIER2 || (flags & IO_NOCACHE)) { take_reference = 0; } if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (flags & IO_NOCACHE) { bflag |= CL_NOCACHE; } if (flags & IO_SKIP_ENCRYPTION) { bflag |= CL_ENCRYPTED; } max_io_size = cluster_max_io_size(vp->v_mount, CL_READ); max_prefetch = cluster_max_prefetch(vp, max_io_size, prefetch_max); max_rd_size = max_prefetch; last_request_offset = uio->uio_offset + io_req_size; if (last_request_offset > filesize) { last_request_offset = filesize; } if ((flags & (IO_RAOFF | IO_NOCACHE)) || ((last_request_offset & ~PAGE_MASK_64) == (uio->uio_offset & ~PAGE_MASK_64))) { rd_ahead_enabled = 0; rap = NULL; } else { if (cluster_is_throttled(vp)) { /* * we're in the throttle window, at the very least * we want to limit the size of the I/O we're about * to issue */ rd_ahead_enabled = 0; prefetch_enabled = 0; max_rd_size = calculate_max_throttle_size(vp); } if ((rap = cluster_get_rap(vp)) == NULL) { rd_ahead_enabled = 0; } else { extent.b_addr = uio->uio_offset / PAGE_SIZE_64; extent.e_addr = (last_request_offset - 1) / PAGE_SIZE_64; } } if (rap != NULL && rap->cl_ralen && (rap->cl_lastr == extent.b_addr || (rap->cl_lastr + 1) == extent.b_addr)) { /* * determine if we already have a read-ahead in the pipe courtesy of the * last read systemcall that was issued... * if so, pick up it's extent to determine where we should start * with respect to any read-ahead that might be necessary to * garner all the data needed to complete this read systemcall */ last_ioread_offset = (rap->cl_maxra * PAGE_SIZE_64) + PAGE_SIZE_64; if (last_ioread_offset < uio->uio_offset) { last_ioread_offset = (off_t)0; } else if (last_ioread_offset > last_request_offset) { last_ioread_offset = last_request_offset; } } else { last_ioread_offset = (off_t)0; } while (io_req_size && uio->uio_offset < filesize && retval == 0) { max_size = filesize - uio->uio_offset; bool leftover_upl_aborted = false; if ((off_t)(io_req_size) < max_size) { io_size = io_req_size; } else { io_size = (u_int32_t)max_size; } if (!(flags & IO_NOCACHE)) { while (io_size) { u_int32_t io_resid; u_int32_t io_requested; /* * if we keep finding the pages we need already in the cache, then * don't bother to call cluster_read_prefetch since it costs CPU cycles * to determine that we have all the pages we need... once we miss in * the cache and have issued an I/O, than we'll assume that we're likely * to continue to miss in the cache and it's to our advantage to try and prefetch */ if (last_request_offset && last_ioread_offset && (size_of_prefetch = (u_int32_t)(last_request_offset - last_ioread_offset))) { if ((last_ioread_offset - uio->uio_offset) <= max_rd_size && prefetch_enabled) { /* * we've already issued I/O for this request and * there's still work to do and * our prefetch stream is running dry, so issue a * pre-fetch I/O... the I/O latency will overlap * with the copying of the data */ if (size_of_prefetch > max_rd_size) { size_of_prefetch = max_rd_size; } size_of_prefetch = cluster_read_prefetch(vp, last_ioread_offset, size_of_prefetch, filesize, callback, callback_arg, bflag); last_ioread_offset += (off_t)(size_of_prefetch * PAGE_SIZE); if (last_ioread_offset > last_request_offset) { last_ioread_offset = last_request_offset; } } } /* * limit the size of the copy we're about to do so that * we can notice that our I/O pipe is running dry and * get the next I/O issued before it does go dry */ if (last_ioread_offset && io_size > (max_io_size / 4)) { io_resid = (max_io_size / 4); } else { io_resid = io_size; } io_requested = io_resid; retval = cluster_copy_ubc_data_internal(vp, uio, (int *)&io_resid, 0, take_reference); xsize = io_requested - io_resid; io_size -= xsize; io_req_size -= xsize; if (retval || io_resid) { /* * if we run into a real error or * a page that is not in the cache * we need to leave streaming mode */ break; } if (rd_ahead_enabled && (io_size == 0 || last_ioread_offset == last_request_offset)) { /* * we're already finished the I/O for this read request * let's see if we should do a read-ahead */ cluster_read_ahead(vp, &extent, filesize, rap, callback, callback_arg, bflag); } } if (retval) { break; } if (io_size == 0) { if (rap != NULL) { if (extent.e_addr < rap->cl_lastr) { rap->cl_maxra = 0; } rap->cl_lastr = extent.e_addr; } break; } /* * recompute max_size since cluster_copy_ubc_data_internal * may have advanced uio->uio_offset */ max_size = filesize - uio->uio_offset; } iostate.io_completed = 0; iostate.io_issued = 0; iostate.io_error = 0; iostate.io_wanted = 0; if ((flags & IO_RETURN_ON_THROTTLE)) { if (cluster_is_throttled(vp) == THROTTLE_NOW) { if (!cluster_io_present_in_BC(vp, uio->uio_offset)) { /* * we're in the throttle window and at least 1 I/O * has already been issued by a throttleable thread * in this window, so return with EAGAIN to indicate * to the FS issuing the cluster_read call that it * should now throttle after dropping any locks */ throttle_info_update_by_mount(vp->v_mount); retval = EAGAIN; break; } } } /* * compute the size of the upl needed to encompass * the requested read... limit each call to cluster_io * to the maximum UPL size... cluster_io will clip if * this exceeds the maximum io_size for the device, * make sure to account for * a starting offset that's not page aligned */ start_offset = (int)(uio->uio_offset & PAGE_MASK_64); upl_f_offset = uio->uio_offset - (off_t)start_offset; if (io_size > max_rd_size) { io_size = max_rd_size; } upl_size = (start_offset + io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if (flags & IO_NOCACHE) { if (upl_size > max_io_size) { upl_size = max_io_size; } } else { if (upl_size > max_io_size / 4) { upl_size = max_io_size / 4; upl_size &= ~PAGE_MASK; if (upl_size == 0) { upl_size = PAGE_SIZE; } } } pages_in_upl = upl_size / PAGE_SIZE; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 33)) | DBG_FUNC_START, upl, (int)upl_f_offset, upl_size, start_offset, 0); kret = ubc_create_upl_kernel(vp, upl_f_offset, upl_size, &upl, &pl, UPL_FILE_IO | UPL_SET_LITE, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { panic("cluster_read_copy: failed to get pagelist"); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 33)) | DBG_FUNC_END, upl, (int)upl_f_offset, upl_size, start_offset, 0); /* * scan from the beginning of the upl looking for the first * non-valid page.... this will become the first page in * the request we're going to make to 'cluster_io'... if all * of the pages are valid, we won't call through to 'cluster_io' */ for (start_pg = 0; start_pg < pages_in_upl; start_pg++) { if (!upl_valid_page(pl, start_pg)) { break; } } /* * scan from the starting invalid page looking for a valid * page before the end of the upl is reached, if we * find one, then it will be the last page of the request to * 'cluster_io' */ for (last_pg = start_pg; last_pg < pages_in_upl; last_pg++) { if (upl_valid_page(pl, last_pg)) { break; } } if (start_pg < last_pg) { /* * we found a range of 'invalid' pages that must be filled * if the last page in this range is the last page of the file * we may have to clip the size of it to keep from reading past * the end of the last physical block associated with the file */ if (iolock_inited == FALSE) { lck_mtx_init(&iostate.io_mtxp, &cl_mtx_grp, LCK_ATTR_NULL); iolock_inited = TRUE; } upl_offset = start_pg * PAGE_SIZE; io_size = (last_pg - start_pg) * PAGE_SIZE; if ((off_t)(upl_f_offset + upl_offset + io_size) > filesize) { io_size = (u_int32_t)(filesize - (upl_f_offset + upl_offset)); } /* * Find out if this needs verification, we'll have to manage the UPL * diffrently if so. Note that this call only lets us know if * verification is enabled on this mount point, the actual verification * is performed in the File system. */ size_t verify_block_size = 0; if ((VNOP_VERIFY(vp, start_offset, NULL, 0, &verify_block_size, NULL, VNODE_VERIFY_DEFAULT, NULL) == 0) /* && verify_block_size */) { for (uio_last = last_pg; uio_last < pages_in_upl; uio_last++) { if (!upl_valid_page(pl, uio_last)) { break; } } if (uio_last < pages_in_upl) { /* * there were some invalid pages beyond the valid pages * that we didn't issue an I/O for, just release them * unchanged now, so that any prefetch/readahed can * include them */ ubc_upl_abort_range(upl, uio_last * PAGE_SIZE, (pages_in_upl - uio_last) * PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); leftover_upl_aborted = true; } } /* * issue an asynchronous read to cluster_io */ error = cluster_io(vp, upl, upl_offset, upl_f_offset + upl_offset, io_size, CL_READ | CL_ASYNC | bflag, (buf_t)NULL, &iostate, callback, callback_arg); if (rap) { if (extent.e_addr < rap->cl_maxra) { /* * we've just issued a read for a block that should have been * in the cache courtesy of the read-ahead engine... something * has gone wrong with the pipeline, so reset the read-ahead * logic which will cause us to restart from scratch */ rap->cl_maxra = 0; } } } if (error == 0) { /* * if the read completed successfully, or there was no I/O request * issued, than copy the data into user land via 'cluster_upl_copy_data' * we'll first add on any 'valid' * pages that were present in the upl when we acquired it. */ u_int val_size; if (!leftover_upl_aborted) { for (uio_last = last_pg; uio_last < pages_in_upl; uio_last++) { if (!upl_valid_page(pl, uio_last)) { break; } } if (uio_last < pages_in_upl) { /* * there were some invalid pages beyond the valid pages * that we didn't issue an I/O for, just release them * unchanged now, so that any prefetch/readahed can * include them */ ubc_upl_abort_range(upl, uio_last * PAGE_SIZE, (pages_in_upl - uio_last) * PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); } } /* * compute size to transfer this round, if io_req_size is * still non-zero after this attempt, we'll loop around and * set up for another I/O. */ val_size = (uio_last * PAGE_SIZE) - start_offset; if (val_size > max_size) { val_size = (u_int)max_size; } if (val_size > io_req_size) { val_size = io_req_size; } if ((uio->uio_offset + val_size) > last_ioread_offset) { last_ioread_offset = uio->uio_offset + val_size; } if ((size_of_prefetch = (u_int32_t)(last_request_offset - last_ioread_offset)) && prefetch_enabled) { if ((last_ioread_offset - (uio->uio_offset + val_size)) <= upl_size) { /* * if there's still I/O left to do for this request, and... * we're not in hard throttle mode, and... * we're close to using up the previous prefetch, then issue a * new pre-fetch I/O... the I/O latency will overlap * with the copying of the data */ if (size_of_prefetch > max_rd_size) { size_of_prefetch = max_rd_size; } size_of_prefetch = cluster_read_prefetch(vp, last_ioread_offset, size_of_prefetch, filesize, callback, callback_arg, bflag); last_ioread_offset += (off_t)(size_of_prefetch * PAGE_SIZE); if (last_ioread_offset > last_request_offset) { last_ioread_offset = last_request_offset; } } } else if ((uio->uio_offset + val_size) == last_request_offset) { /* * this transfer will finish this request, so... * let's try to read ahead if we're in * a sequential access pattern and we haven't * explicitly disabled it */ if (rd_ahead_enabled) { cluster_read_ahead(vp, &extent, filesize, rap, callback, callback_arg, bflag); } if (rap != NULL) { if (extent.e_addr < rap->cl_lastr) { rap->cl_maxra = 0; } rap->cl_lastr = extent.e_addr; } } if (iolock_inited == TRUE) { cluster_iostate_wait(&iostate, 0, "cluster_read_copy"); } if (iostate.io_error) { error = iostate.io_error; } else { u_int32_t io_requested; io_requested = val_size; retval = cluster_copy_upl_data(uio, upl, start_offset, (int *)&io_requested); io_req_size -= (val_size - io_requested); } } else { if (iolock_inited == TRUE) { cluster_iostate_wait(&iostate, 0, "cluster_read_copy"); } } if (start_pg < last_pg) { /* * compute the range of pages that we actually issued an I/O for * and either commit them as valid if the I/O succeeded * or abort them if the I/O failed or we're not supposed to * keep them in the cache */ io_size = (last_pg - start_pg) * PAGE_SIZE; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 35)) | DBG_FUNC_START, upl, start_pg * PAGE_SIZE, io_size, error, 0); if (error || (flags & IO_NOCACHE)) { ubc_upl_abort_range(upl, start_pg * PAGE_SIZE, io_size, UPL_ABORT_DUMP_PAGES | UPL_ABORT_FREE_ON_EMPTY); } else { int commit_flags = UPL_COMMIT_CLEAR_DIRTY | UPL_COMMIT_FREE_ON_EMPTY; if (take_reference) { commit_flags |= UPL_COMMIT_INACTIVATE; } else { commit_flags |= UPL_COMMIT_SPECULATE; } ubc_upl_commit_range(upl, start_pg * PAGE_SIZE, io_size, commit_flags); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 35)) | DBG_FUNC_END, upl, start_pg * PAGE_SIZE, io_size, error, 0); } if ((last_pg - start_pg) < pages_in_upl) { /* * the set of pages that we issued an I/O for did not encompass * the entire upl... so just release these without modifying * their state */ if (error) { if (leftover_upl_aborted) { ubc_upl_abort_range(upl, start_pg * PAGE_SIZE, (uio_last - start_pg) * PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); } else { ubc_upl_abort_range(upl, 0, upl_size, UPL_ABORT_FREE_ON_EMPTY); } } else { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 35)) | DBG_FUNC_START, upl, -1, pages_in_upl - (last_pg - start_pg), 0, 0); /* * handle any valid pages at the beginning of * the upl... release these appropriately */ cluster_read_upl_release(upl, 0, start_pg, take_reference); /* * handle any valid pages immediately after the * pages we issued I/O for... ... release these appropriately */ cluster_read_upl_release(upl, last_pg, uio_last, take_reference); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 35)) | DBG_FUNC_END, upl, -1, -1, 0, 0); } } if (retval == 0) { retval = error; } if (io_req_size) { uint32_t max_throttle_size = calculate_max_throttle_size(vp); if (cluster_is_throttled(vp)) { /* * we're in the throttle window, at the very least * we want to limit the size of the I/O we're about * to issue */ rd_ahead_enabled = 0; prefetch_enabled = 0; max_rd_size = max_throttle_size; } else { if (max_rd_size == max_throttle_size) { /* * coming out of throttled state */ if (policy != THROTTLE_LEVEL_TIER3 && policy != THROTTLE_LEVEL_TIER2) { if (rap != NULL) { rd_ahead_enabled = 1; } prefetch_enabled = 1; } max_rd_size = max_prefetch; last_ioread_offset = 0; } } } } if (iolock_inited == TRUE) { /* * cluster_io returned an error after it * had already issued some I/O. we need * to wait for that I/O to complete before * we can destroy the iostate mutex... * 'retval' already contains the early error * so no need to pick it up from iostate.io_error */ cluster_iostate_wait(&iostate, 0, "cluster_read_copy"); lck_mtx_destroy(&iostate.io_mtxp, &cl_mtx_grp); } if (rap != NULL) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 32)) | DBG_FUNC_END, (int)uio->uio_offset, io_req_size, rap->cl_lastr, retval, 0); lck_mtx_unlock(&rap->cl_lockr); } else { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 32)) | DBG_FUNC_END, (int)uio->uio_offset, io_req_size, 0, retval, 0); } return retval; } /* * We don't want another read/write lock for every vnode in the system * so we keep a hash of them here. There should never be very many of * these around at any point in time. */ cl_direct_read_lock_t * cluster_lock_direct_read(vnode_t vp, lck_rw_type_t type) { struct cl_direct_read_locks *head = &cl_direct_read_locks[(uintptr_t)vp / sizeof(*vp) % CL_DIRECT_READ_LOCK_BUCKETS]; struct cl_direct_read_lock *lck, *new_lck = NULL; for (;;) { lck_spin_lock(&cl_direct_read_spin_lock); LIST_FOREACH(lck, head, chain) { if (lck->vp == vp) { ++lck->ref_count; lck_spin_unlock(&cl_direct_read_spin_lock); if (new_lck) { // Someone beat us to it, ditch the allocation lck_rw_destroy(&new_lck->rw_lock, &cl_mtx_grp); kfree_type(cl_direct_read_lock_t, new_lck); } lck_rw_lock(&lck->rw_lock, type); return lck; } } if (new_lck) { // Use the lock we allocated LIST_INSERT_HEAD(head, new_lck, chain); lck_spin_unlock(&cl_direct_read_spin_lock); lck_rw_lock(&new_lck->rw_lock, type); return new_lck; } lck_spin_unlock(&cl_direct_read_spin_lock); // Allocate a new lock new_lck = kalloc_type(cl_direct_read_lock_t, Z_WAITOK); lck_rw_init(&new_lck->rw_lock, &cl_mtx_grp, LCK_ATTR_NULL); new_lck->vp = vp; new_lck->ref_count = 1; // Got to go round again } } void cluster_unlock_direct_read(cl_direct_read_lock_t *lck) { lck_rw_done(&lck->rw_lock); lck_spin_lock(&cl_direct_read_spin_lock); if (lck->ref_count == 1) { LIST_REMOVE(lck, chain); lck_spin_unlock(&cl_direct_read_spin_lock); lck_rw_destroy(&lck->rw_lock, &cl_mtx_grp); kfree_type(cl_direct_read_lock_t, lck); } else { --lck->ref_count; lck_spin_unlock(&cl_direct_read_spin_lock); } } static int cluster_read_direct(vnode_t vp, struct uio *uio, off_t filesize, int *read_type, u_int32_t *read_length, int flags, int (*callback)(buf_t, void *), void *callback_arg) { upl_t upl = NULL; upl_page_info_t *pl; off_t max_io_size; vm_offset_t upl_offset, vector_upl_offset = 0; upl_size_t upl_size = 0, vector_upl_size = 0; vm_size_t upl_needed_size; unsigned int pages_in_pl; upl_control_flags_t upl_flags; kern_return_t kret = KERN_SUCCESS; unsigned int i; int force_data_sync; int retval = 0; int no_zero_fill = 0; int io_flag = 0; int misaligned = 0; struct clios iostate; user_addr_t iov_base; u_int32_t io_req_size; u_int32_t offset_in_file; u_int32_t offset_in_iovbase; u_int32_t io_size; u_int32_t io_min; u_int32_t xsize; u_int32_t devblocksize; u_int32_t mem_alignment_mask; u_int32_t max_upl_size; u_int32_t max_rd_size; u_int32_t max_rd_ahead; u_int32_t max_vector_size; boolean_t io_throttled = FALSE; u_int32_t vector_upl_iosize = 0; int issueVectorUPL = 0, useVectorUPL = (uio->uio_iovcnt > 1); off_t v_upl_uio_offset = 0; int vector_upl_index = 0; upl_t vector_upl = NULL; cl_direct_read_lock_t *lock = NULL; assert(vm_map_page_shift(current_map()) >= PAGE_SHIFT); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 70)) | DBG_FUNC_START, (int)uio->uio_offset, (int)filesize, *read_type, *read_length, 0); max_upl_size = cluster_max_io_size(vp->v_mount, CL_READ); max_rd_size = max_upl_size; if (__improbable(os_mul_overflow(max_rd_size, IO_SCALE(vp, 2), &max_rd_ahead) || (max_rd_ahead > overlapping_read_max))) { max_rd_ahead = overlapping_read_max; } io_flag = CL_COMMIT | CL_READ | CL_ASYNC | CL_NOZERO | CL_DIRECT_IO; if (flags & IO_PASSIVE) { io_flag |= CL_PASSIVE; } if (flags & IO_ENCRYPTED) { io_flag |= CL_RAW_ENCRYPTED; } if (flags & IO_NOCACHE) { io_flag |= CL_NOCACHE; } if (flags & IO_SKIP_ENCRYPTION) { io_flag |= CL_ENCRYPTED; } iostate.io_completed = 0; iostate.io_issued = 0; iostate.io_error = 0; iostate.io_wanted = 0; lck_mtx_init(&iostate.io_mtxp, &cl_mtx_grp, LCK_ATTR_NULL); devblocksize = (u_int32_t)vp->v_mount->mnt_devblocksize; mem_alignment_mask = (u_int32_t)vp->v_mount->mnt_alignmentmask; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 70)) | DBG_FUNC_NONE, (int)devblocksize, (int)mem_alignment_mask, 0, 0, 0); if (devblocksize == 1) { /* * the AFP client advertises a devblocksize of 1 * however, its BLOCKMAP routine maps to physical * blocks that are PAGE_SIZE in size... * therefore we can't ask for I/Os that aren't page aligned * or aren't multiples of PAGE_SIZE in size * by setting devblocksize to PAGE_SIZE, we re-instate * the old behavior we had before the mem_alignment_mask * changes went in... */ devblocksize = PAGE_SIZE; } /* * We are going to need this uio for the prefaulting later * especially for the cases where multiple non-contiguous * iovs are passed into this routine. */ uio_t uio_acct = uio_duplicate(uio); next_dread: io_req_size = *read_length; iov_base = uio_curriovbase(uio); offset_in_file = (u_int32_t)uio->uio_offset & (devblocksize - 1); offset_in_iovbase = (u_int32_t)iov_base & mem_alignment_mask; if (vm_map_page_mask(current_map()) < PAGE_MASK) { /* * XXX TODO4K * Direct I/O might not work as expected from a 16k kernel space * to a 4k user space because each 4k chunk might point to * a different 16k physical page... * Let's go the "misaligned" way. */ if (!misaligned) { DEBUG4K_VFS("forcing misaligned\n"); } misaligned = 1; } if (offset_in_file || offset_in_iovbase) { /* * one of the 2 important offsets is misaligned * so fire an I/O through the cache for this entire vector */ misaligned = 1; } if (iov_base & (devblocksize - 1)) { /* * the offset in memory must be on a device block boundary * so that we can guarantee that we can generate an * I/O that ends on a page boundary in cluster_io */ misaligned = 1; } max_io_size = filesize - uio->uio_offset; /* * The user must request IO in aligned chunks. If the * offset into the file is bad, or the userland pointer * is non-aligned, then we cannot service the encrypted IO request. */ if (flags & IO_ENCRYPTED) { if (misaligned || (io_req_size & (devblocksize - 1))) { retval = EINVAL; } max_io_size = roundup(max_io_size, devblocksize); } if ((off_t)io_req_size > max_io_size) { io_req_size = (u_int32_t)max_io_size; } /* * When we get to this point, we know... * -- the offset into the file is on a devblocksize boundary */ while (io_req_size && retval == 0) { u_int32_t io_start; if (cluster_is_throttled(vp)) { uint32_t max_throttle_size = calculate_max_throttle_size(vp); /* * we're in the throttle window, at the very least * we want to limit the size of the I/O we're about * to issue */ max_rd_size = max_throttle_size; max_rd_ahead = max_throttle_size - 1; max_vector_size = max_throttle_size; } else { max_rd_size = max_upl_size; max_rd_ahead = max_rd_size * IO_SCALE(vp, 2); max_vector_size = MAX_VECTOR_UPL_SIZE; } io_start = io_size = io_req_size; /* * First look for pages already in the cache * and move them to user space. But only do this * check if we are not retrieving encrypted data directly * from the filesystem; those blocks should never * be in the UBC. * * cluster_copy_ubc_data returns the resid * in io_size */ if ((flags & IO_ENCRYPTED) == 0) { retval = cluster_copy_ubc_data_internal(vp, uio, (int *)&io_size, 0, 0); } /* * calculate the number of bytes actually copied * starting size - residual */ xsize = io_start - io_size; io_req_size -= xsize; if (useVectorUPL && (xsize || (iov_base & PAGE_MASK))) { /* * We found something in the cache or we have an iov_base that's not * page-aligned. * * Issue all I/O's that have been collected within this Vectored UPL. */ if (vector_upl_index) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } if (xsize) { useVectorUPL = 0; } /* * After this point, if we are using the Vector UPL path and the base is * not page-aligned then the UPL with that base will be the first in the vector UPL. */ } /* * check to see if we are finished with this request. * * If we satisfied this IO already, then io_req_size will be 0. * Otherwise, see if the IO was mis-aligned and needs to go through * the UBC to deal with the 'tail'. * */ if (io_req_size == 0 || (misaligned)) { /* * see if there's another uio vector to * process that's of type IO_DIRECT * * break out of while loop to get there */ break; } /* * assume the request ends on a device block boundary */ io_min = devblocksize; /* * we can handle I/O's in multiples of the device block size * however, if io_size isn't a multiple of devblocksize we * want to clip it back to the nearest page boundary since * we are going to have to go through cluster_read_copy to * deal with the 'overhang'... by clipping it to a PAGE_SIZE * multiple, we avoid asking the drive for the same physical * blocks twice.. once for the partial page at the end of the * request and a 2nd time for the page we read into the cache * (which overlaps the end of the direct read) in order to * get at the overhang bytes */ if (io_size & (devblocksize - 1)) { assert(!(flags & IO_ENCRYPTED)); /* * Clip the request to the previous page size boundary * since request does NOT end on a device block boundary */ io_size &= ~PAGE_MASK; io_min = PAGE_SIZE; } if (retval || io_size < io_min) { /* * either an error or we only have the tail left to * complete via the copy path... * we may have already spun some portion of this request * off as async requests... we need to wait for the I/O * to complete before returning */ goto wait_for_dreads; } /* * Don't re-check the UBC data if we are looking for uncached IO * or asking for encrypted blocks. */ if ((flags & IO_ENCRYPTED) == 0) { if ((xsize = io_size) > max_rd_size) { xsize = max_rd_size; } io_size = 0; if (!lock) { /* * We hold a lock here between the time we check the * cache and the time we issue I/O. This saves us * from having to lock the pages in the cache. Not * all clients will care about this lock but some * clients may want to guarantee stability between * here and when the I/O is issued in which case they * will take the lock exclusively. */ lock = cluster_lock_direct_read(vp, LCK_RW_TYPE_SHARED); } ubc_range_op(vp, uio->uio_offset, uio->uio_offset + xsize, UPL_ROP_ABSENT, (int *)&io_size); if (io_size == 0) { /* * a page must have just come into the cache * since the first page in this range is no * longer absent, go back and re-evaluate */ continue; } } if ((flags & IO_RETURN_ON_THROTTLE)) { if (cluster_is_throttled(vp) == THROTTLE_NOW) { if (!cluster_io_present_in_BC(vp, uio->uio_offset)) { /* * we're in the throttle window and at least 1 I/O * has already been issued by a throttleable thread * in this window, so return with EAGAIN to indicate * to the FS issuing the cluster_read call that it * should now throttle after dropping any locks */ throttle_info_update_by_mount(vp->v_mount); io_throttled = TRUE; goto wait_for_dreads; } } } if (io_size > max_rd_size) { io_size = max_rd_size; } iov_base = uio_curriovbase(uio); upl_offset = (vm_offset_t)((u_int32_t)iov_base & PAGE_MASK); upl_needed_size = (upl_offset + io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 72)) | DBG_FUNC_START, (int)upl_offset, upl_needed_size, (int)iov_base, io_size, 0); if (upl_offset == 0 && ((io_size & PAGE_MASK) == 0)) { no_zero_fill = 1; } else { no_zero_fill = 0; } vm_map_t map = UIO_SEG_IS_USER_SPACE(uio->uio_segflg) ? current_map() : kernel_map; for (force_data_sync = 0; force_data_sync < 3; force_data_sync++) { pages_in_pl = 0; upl_size = (upl_size_t)upl_needed_size; upl_flags = UPL_FILE_IO | UPL_NO_SYNC | UPL_SET_INTERNAL | UPL_SET_LITE | UPL_SET_IO_WIRE; if (no_zero_fill) { upl_flags |= UPL_NOZEROFILL; } if (force_data_sync) { upl_flags |= UPL_FORCE_DATA_SYNC; } kret = vm_map_create_upl(map, (vm_map_offset_t)(iov_base & ~((user_addr_t)PAGE_MASK)), &upl_size, &upl, NULL, &pages_in_pl, &upl_flags, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 72)) | DBG_FUNC_END, (int)upl_offset, upl_size, io_size, kret, 0); /* * failed to get pagelist * * we may have already spun some portion of this request * off as async requests... we need to wait for the I/O * to complete before returning */ goto wait_for_dreads; } pages_in_pl = upl_size / PAGE_SIZE; pl = UPL_GET_INTERNAL_PAGE_LIST(upl); for (i = 0; i < pages_in_pl; i++) { if (!upl_page_present(pl, i)) { break; } } if (i == pages_in_pl) { break; } ubc_upl_abort(upl, 0); } if (force_data_sync >= 3) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 72)) | DBG_FUNC_END, (int)upl_offset, upl_size, io_size, kret, 0); goto wait_for_dreads; } /* * Consider the possibility that upl_size wasn't satisfied. */ if (upl_size < upl_needed_size) { if (upl_size && upl_offset == 0) { io_size = upl_size; } else { io_size = 0; } } if (io_size == 0) { ubc_upl_abort(upl, 0); goto wait_for_dreads; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 72)) | DBG_FUNC_END, (int)upl_offset, upl_size, io_size, kret, 0); if (useVectorUPL) { vm_offset_t end_off = ((iov_base + io_size) & PAGE_MASK); if (end_off) { issueVectorUPL = 1; } /* * After this point, if we are using a vector UPL, then * either all the UPL elements end on a page boundary OR * this UPL is the last element because it does not end * on a page boundary. */ } /* * request asynchronously so that we can overlap * the preparation of the next I/O * if there are already too many outstanding reads * wait until some have completed before issuing the next read */ cluster_iostate_wait(&iostate, max_rd_ahead, "cluster_read_direct"); if (iostate.io_error) { /* * one of the earlier reads we issued ran into a hard error * don't issue any more reads, cleanup the UPL * that was just created but not used, then * go wait for any other reads to complete before * returning the error to the caller */ ubc_upl_abort(upl, 0); goto wait_for_dreads; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 73)) | DBG_FUNC_START, upl, (int)upl_offset, (int)uio->uio_offset, io_size, 0); if (!useVectorUPL) { if (no_zero_fill) { io_flag &= ~CL_PRESERVE; } else { io_flag |= CL_PRESERVE; } retval = cluster_io(vp, upl, upl_offset, uio->uio_offset, io_size, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); } else { if (!vector_upl_index) { vector_upl = vector_upl_create(upl_offset, uio->uio_iovcnt); v_upl_uio_offset = uio->uio_offset; vector_upl_offset = upl_offset; } vector_upl_set_subupl(vector_upl, upl, upl_size); vector_upl_set_iostate(vector_upl, upl, vector_upl_size, upl_size); vector_upl_index++; vector_upl_size += upl_size; vector_upl_iosize += io_size; if (issueVectorUPL || vector_upl_index == vector_upl_max_upls(vector_upl) || vector_upl_size >= max_vector_size) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } } if (lock) { // We don't need to wait for the I/O to complete cluster_unlock_direct_read(lock); lock = NULL; } /* * update the uio structure */ if ((flags & IO_ENCRYPTED) && (max_io_size < io_size)) { uio_update(uio, (user_size_t)max_io_size); } else { uio_update(uio, (user_size_t)io_size); } io_req_size -= io_size; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 73)) | DBG_FUNC_END, upl, (int)uio->uio_offset, io_req_size, retval, 0); } /* end while */ if (retval == 0 && iostate.io_error == 0 && io_req_size == 0 && uio->uio_offset < filesize) { retval = cluster_io_type(uio, read_type, read_length, 0); if (retval == 0 && *read_type == IO_DIRECT) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 70)) | DBG_FUNC_NONE, (int)uio->uio_offset, (int)filesize, *read_type, *read_length, 0); goto next_dread; } } wait_for_dreads: if (retval == 0 && iostate.io_error == 0 && useVectorUPL && vector_upl_index) { retval = vector_cluster_io(vp, vector_upl, vector_upl_offset, v_upl_uio_offset, vector_upl_iosize, io_flag, (buf_t)NULL, &iostate, callback, callback_arg); reset_vector_run_state(); } // We don't need to wait for the I/O to complete if (lock) { cluster_unlock_direct_read(lock); } /* * make sure all async reads that are part of this stream * have completed before we return */ cluster_iostate_wait(&iostate, 0, "cluster_read_direct"); if (iostate.io_error) { retval = iostate.io_error; } lck_mtx_destroy(&iostate.io_mtxp, &cl_mtx_grp); if (io_throttled == TRUE && retval == 0) { retval = EAGAIN; } vm_map_offset_t current_page_size, current_page_mask; current_page_size = vm_map_page_size(current_map()); current_page_mask = vm_map_page_mask(current_map()); if (uio_acct) { off_t bytes_to_prefault = 0, bytes_prefaulted = 0; user_addr_t curr_iov_base = 0; user_addr_t curr_iov_end = 0; user_size_t curr_iov_len = 0; bytes_to_prefault = uio_offset(uio) - uio_offset(uio_acct); for (; bytes_prefaulted < bytes_to_prefault;) { curr_iov_base = uio_curriovbase(uio_acct); curr_iov_len = MIN(uio_curriovlen(uio_acct), bytes_to_prefault - bytes_prefaulted); curr_iov_end = curr_iov_base + curr_iov_len; for (; curr_iov_base < curr_iov_end;) { /* * This is specifically done for pmap accounting purposes. * vm_pre_fault() will call vm_fault() to enter the page into * the pmap if there isn't _a_ physical page for that VA already. */ vm_pre_fault(vm_map_trunc_page(curr_iov_base, current_page_mask), VM_PROT_READ); curr_iov_base += current_page_size; bytes_prefaulted += current_page_size; } /* * Use update instead of advance so we can see how many iovs we processed. */ uio_update(uio_acct, curr_iov_len); } uio_free(uio_acct); uio_acct = NULL; } if (io_req_size && retval == 0) { /* * we couldn't handle the tail of this request in DIRECT mode * so fire it through the copy path */ if (flags & IO_ENCRYPTED) { /* * We cannot fall back to the copy path for encrypted I/O. If this * happens, there is something wrong with the user buffer passed * down. */ retval = EFAULT; } else { retval = cluster_read_copy(vp, uio, io_req_size, filesize, flags, callback, callback_arg); } *read_type = IO_UNKNOWN; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 70)) | DBG_FUNC_END, (int)uio->uio_offset, (int)uio_resid(uio), io_req_size, retval, 0); return retval; } static int cluster_read_contig(vnode_t vp, struct uio *uio, off_t filesize, int *read_type, u_int32_t *read_length, int (*callback)(buf_t, void *), void *callback_arg, int flags) { upl_page_info_t *pl; upl_t upl[MAX_VECTS]; vm_offset_t upl_offset; addr64_t dst_paddr = 0; user_addr_t iov_base; off_t max_size; upl_size_t upl_size; vm_size_t upl_needed_size; mach_msg_type_number_t pages_in_pl; upl_control_flags_t upl_flags; kern_return_t kret; struct clios iostate; int error = 0; int cur_upl = 0; int num_upl = 0; int n; u_int32_t xsize; u_int32_t io_size; u_int32_t devblocksize; u_int32_t mem_alignment_mask; u_int32_t tail_size = 0; int bflag; if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (flags & IO_NOCACHE) { bflag |= CL_NOCACHE; } /* * When we enter this routine, we know * -- the read_length will not exceed the current iov_len * -- the target address is physically contiguous for read_length */ cluster_syncup(vp, filesize, callback, callback_arg, PUSH_SYNC); devblocksize = (u_int32_t)vp->v_mount->mnt_devblocksize; mem_alignment_mask = (u_int32_t)vp->v_mount->mnt_alignmentmask; iostate.io_completed = 0; iostate.io_issued = 0; iostate.io_error = 0; iostate.io_wanted = 0; lck_mtx_init(&iostate.io_mtxp, &cl_mtx_grp, LCK_ATTR_NULL); next_cread: io_size = *read_length; max_size = filesize - uio->uio_offset; if (io_size > max_size) { io_size = (u_int32_t)max_size; } iov_base = uio_curriovbase(uio); upl_offset = (vm_offset_t)((u_int32_t)iov_base & PAGE_MASK); upl_needed_size = upl_offset + io_size; pages_in_pl = 0; upl_size = (upl_size_t)upl_needed_size; upl_flags = UPL_FILE_IO | UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | UPL_SET_INTERNAL | UPL_SET_LITE | UPL_SET_IO_WIRE; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 92)) | DBG_FUNC_START, (int)upl_offset, (int)upl_size, (int)iov_base, io_size, 0); vm_map_t map = UIO_SEG_IS_USER_SPACE(uio->uio_segflg) ? current_map() : kernel_map; kret = vm_map_get_upl(map, vm_map_trunc_page(iov_base, vm_map_page_mask(map)), &upl_size, &upl[cur_upl], NULL, &pages_in_pl, &upl_flags, VM_KERN_MEMORY_FILE, 0); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 92)) | DBG_FUNC_END, (int)upl_offset, upl_size, io_size, kret, 0); if (kret != KERN_SUCCESS) { /* * failed to get pagelist */ error = EINVAL; goto wait_for_creads; } num_upl++; if (upl_size < upl_needed_size) { /* * The upl_size wasn't satisfied. */ error = EINVAL; goto wait_for_creads; } pl = ubc_upl_pageinfo(upl[cur_upl]); dst_paddr = ((addr64_t)upl_phys_page(pl, 0) << PAGE_SHIFT) + (addr64_t)upl_offset; while (((uio->uio_offset & (devblocksize - 1)) || io_size < devblocksize) && io_size) { u_int32_t head_size; head_size = devblocksize - (u_int32_t)(uio->uio_offset & (devblocksize - 1)); if (head_size > io_size) { head_size = io_size; } error = cluster_align_phys_io(vp, uio, dst_paddr, head_size, CL_READ, callback, callback_arg); if (error) { goto wait_for_creads; } upl_offset += head_size; dst_paddr += head_size; io_size -= head_size; iov_base += head_size; } if ((u_int32_t)iov_base & mem_alignment_mask) { /* * request doesn't set up on a memory boundary * the underlying DMA engine can handle... * return an error instead of going through * the slow copy path since the intent of this * path is direct I/O to device memory */ error = EINVAL; goto wait_for_creads; } tail_size = io_size & (devblocksize - 1); io_size -= tail_size; while (io_size && error == 0) { if (io_size > MAX_IO_CONTIG_SIZE) { xsize = MAX_IO_CONTIG_SIZE; } else { xsize = io_size; } /* * request asynchronously so that we can overlap * the preparation of the next I/O... we'll do * the commit after all the I/O has completed * since its all issued against the same UPL * if there are already too many outstanding reads * wait until some have completed before issuing the next */ cluster_iostate_wait(&iostate, MAX_IO_CONTIG_SIZE * IO_SCALE(vp, 2), "cluster_read_contig"); if (iostate.io_error) { /* * one of the earlier reads we issued ran into a hard error * don't issue any more reads... * go wait for any other reads to complete before * returning the error to the caller */ goto wait_for_creads; } error = cluster_io(vp, upl[cur_upl], upl_offset, uio->uio_offset, xsize, CL_READ | CL_NOZERO | CL_DEV_MEMORY | CL_ASYNC | bflag, (buf_t)NULL, &iostate, callback, callback_arg); /* * The cluster_io read was issued successfully, * update the uio structure */ if (error == 0) { uio_update(uio, (user_size_t)xsize); dst_paddr += xsize; upl_offset += xsize; io_size -= xsize; } } if (error == 0 && iostate.io_error == 0 && tail_size == 0 && num_upl < MAX_VECTS && uio->uio_offset < filesize) { error = cluster_io_type(uio, read_type, read_length, 0); if (error == 0 && *read_type == IO_CONTIG) { cur_upl++; goto next_cread; } } else { *read_type = IO_UNKNOWN; } wait_for_creads: /* * make sure all async reads that are part of this stream * have completed before we proceed */ cluster_iostate_wait(&iostate, 0, "cluster_read_contig"); if (iostate.io_error) { error = iostate.io_error; } lck_mtx_destroy(&iostate.io_mtxp, &cl_mtx_grp); if (error == 0 && tail_size) { error = cluster_align_phys_io(vp, uio, dst_paddr, tail_size, CL_READ, callback, callback_arg); } for (n = 0; n < num_upl; n++) { /* * just release our hold on each physically contiguous * region without changing any state */ ubc_upl_abort(upl[n], 0); } return error; } static int cluster_io_type(struct uio *uio, int *io_type, u_int32_t *io_length, u_int32_t min_length) { user_size_t iov_len; user_addr_t iov_base = 0; upl_t upl; upl_size_t upl_size; upl_control_flags_t upl_flags; int retval = 0; /* * skip over any emtpy vectors */ uio_update(uio, (user_size_t)0); iov_len = uio_curriovlen(uio); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 94)) | DBG_FUNC_START, uio, (int)iov_len, 0, 0, 0); if (iov_len) { iov_base = uio_curriovbase(uio); /* * make sure the size of the vector isn't too big... * internally, we want to handle all of the I/O in * chunk sizes that fit in a 32 bit int */ if (iov_len > (user_size_t)MAX_IO_REQUEST_SIZE) { upl_size = MAX_IO_REQUEST_SIZE; } else { upl_size = (u_int32_t)iov_len; } upl_flags = UPL_QUERY_OBJECT_TYPE; vm_map_t map = UIO_SEG_IS_USER_SPACE(uio->uio_segflg) ? current_map() : kernel_map; if ((vm_map_get_upl(map, vm_map_trunc_page(iov_base, vm_map_page_mask(map)), &upl_size, &upl, NULL, NULL, &upl_flags, VM_KERN_MEMORY_FILE, 0)) != KERN_SUCCESS) { /* * the user app must have passed in an invalid address */ retval = EFAULT; } if (upl_size == 0) { retval = EFAULT; } *io_length = upl_size; if (upl_flags & UPL_PHYS_CONTIG) { *io_type = IO_CONTIG; } else if (iov_len >= min_length) { *io_type = IO_DIRECT; } else { *io_type = IO_COPY; } } else { /* * nothing left to do for this uio */ *io_length = 0; *io_type = IO_UNKNOWN; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 94)) | DBG_FUNC_END, iov_base, *io_type, *io_length, retval, 0); if (*io_type == IO_DIRECT && vm_map_page_shift(current_map()) < PAGE_SHIFT) { /* no direct I/O for sub-page-size address spaces */ DEBUG4K_VFS("io_type IO_DIRECT -> IO_COPY\n"); *io_type = IO_COPY; } return retval; } /* * generate advisory I/O's in the largest chunks possible * the completed pages will be released into the VM cache */ int advisory_read(vnode_t vp, off_t filesize, off_t f_offset, int resid) { return advisory_read_ext(vp, filesize, f_offset, resid, NULL, NULL, CL_PASSIVE); } int advisory_read_ext(vnode_t vp, off_t filesize, off_t f_offset, int resid, int (*callback)(buf_t, void *), void *callback_arg, int bflag) { upl_page_info_t *pl; upl_t upl = NULL; vm_offset_t upl_offset; int upl_size; off_t upl_f_offset; int start_offset; int start_pg; int last_pg; int pages_in_upl; off_t max_size; int io_size; kern_return_t kret; int retval = 0; int issued_io; int skip_range; uint32_t max_io_size; if (!UBCINFOEXISTS(vp)) { return EINVAL; } if (f_offset < 0 || resid < 0) { return EINVAL; } max_io_size = cluster_max_io_size(vp->v_mount, CL_READ); if (disk_conditioner_mount_is_ssd(vp->v_mount)) { if (max_io_size > speculative_prefetch_max_iosize) { max_io_size = speculative_prefetch_max_iosize; } } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 60)) | DBG_FUNC_START, (int)f_offset, resid, (int)filesize, 0, 0); while (resid && f_offset < filesize && retval == 0) { /* * compute the size of the upl needed to encompass * the requested read... limit each call to cluster_io * to the maximum UPL size... cluster_io will clip if * this exceeds the maximum io_size for the device, * make sure to account for * a starting offset that's not page aligned */ start_offset = (int)(f_offset & PAGE_MASK_64); upl_f_offset = f_offset - (off_t)start_offset; max_size = filesize - f_offset; if (resid < max_size) { io_size = resid; } else { io_size = (int)max_size; } upl_size = (start_offset + io_size + (PAGE_SIZE - 1)) & ~PAGE_MASK; if ((uint32_t)upl_size > max_io_size) { upl_size = max_io_size; } skip_range = 0; /* * return the number of contiguously present pages in the cache * starting at upl_f_offset within the file */ ubc_range_op(vp, upl_f_offset, upl_f_offset + upl_size, UPL_ROP_PRESENT, &skip_range); if (skip_range) { /* * skip over pages already present in the cache */ io_size = skip_range - start_offset; f_offset += io_size; resid -= io_size; if (skip_range == upl_size) { continue; } /* * have to issue some real I/O * at this point, we know it's starting on a page boundary * because we've skipped over at least the first page in the request */ start_offset = 0; upl_f_offset += skip_range; upl_size -= skip_range; } pages_in_upl = upl_size / PAGE_SIZE; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 61)) | DBG_FUNC_START, upl, (int)upl_f_offset, upl_size, start_offset, 0); kret = ubc_create_upl_kernel(vp, upl_f_offset, upl_size, &upl, &pl, UPL_RET_ONLY_ABSENT | UPL_SET_LITE, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { return retval; } issued_io = 0; /* * before we start marching forward, we must make sure we end on * a present page, otherwise we will be working with a freed * upl */ for (last_pg = pages_in_upl - 1; last_pg >= 0; last_pg--) { if (upl_page_present(pl, last_pg)) { break; } } pages_in_upl = last_pg + 1; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 61)) | DBG_FUNC_END, upl, (int)upl_f_offset, upl_size, start_offset, 0); for (last_pg = 0; last_pg < pages_in_upl;) { /* * scan from the beginning of the upl looking for the first * page that is present.... this will become the first page in * the request we're going to make to 'cluster_io'... if all * of the pages are absent, we won't call through to 'cluster_io' */ for (start_pg = last_pg; start_pg < pages_in_upl; start_pg++) { if (upl_page_present(pl, start_pg)) { break; } } /* * scan from the starting present page looking for an absent * page before the end of the upl is reached, if we * find one, then it will terminate the range of pages being * presented to 'cluster_io' */ for (last_pg = start_pg; last_pg < pages_in_upl; last_pg++) { if (!upl_page_present(pl, last_pg)) { break; } } if (last_pg > start_pg) { /* * we found a range of pages that must be filled * if the last page in this range is the last page of the file * we may have to clip the size of it to keep from reading past * the end of the last physical block associated with the file */ upl_offset = start_pg * PAGE_SIZE; io_size = (last_pg - start_pg) * PAGE_SIZE; if ((off_t)(upl_f_offset + upl_offset + io_size) > filesize) { io_size = (int)(filesize - (upl_f_offset + upl_offset)); } /* * issue an asynchronous read to cluster_io */ retval = cluster_io(vp, upl, upl_offset, upl_f_offset + upl_offset, io_size, CL_ASYNC | CL_READ | CL_COMMIT | CL_AGE | bflag, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); issued_io = 1; } } if (issued_io == 0) { ubc_upl_abort(upl, 0); } io_size = upl_size - start_offset; if (io_size > resid) { io_size = resid; } f_offset += io_size; resid -= io_size; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 60)) | DBG_FUNC_END, (int)f_offset, resid, retval, 0, 0); return retval; } int cluster_push(vnode_t vp, int flags) { return cluster_push_ext(vp, flags, NULL, NULL); } int cluster_push_ext(vnode_t vp, int flags, int (*callback)(buf_t, void *), void *callback_arg) { return cluster_push_err(vp, flags, callback, callback_arg, NULL); } /* write errors via err, but return the number of clusters written */ extern uint32_t system_inshutdown; uint32_t cl_sparse_push_error = 0; int cluster_push_err(vnode_t vp, int flags, int (*callback)(buf_t, void *), void *callback_arg, int *err) { int retval; int my_sparse_wait = 0; struct cl_writebehind *wbp; int local_err = 0; if (err) { *err = 0; } if (!UBCINFOEXISTS(vp)) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 53)) | DBG_FUNC_NONE, kdebug_vnode(vp), flags, 0, -1, 0); return 0; } /* return if deferred write is set */ if (((unsigned int)vfs_flags(vp->v_mount) & MNT_DEFWRITE) && (flags & IO_DEFWRITE)) { return 0; } if ((wbp = cluster_get_wbp(vp, CLW_RETURNLOCKED)) == NULL) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 53)) | DBG_FUNC_NONE, kdebug_vnode(vp), flags, 0, -2, 0); return 0; } if (!ISSET(flags, IO_SYNC) && wbp->cl_number == 0 && wbp->cl_scmap == NULL) { lck_mtx_unlock(&wbp->cl_lockw); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 53)) | DBG_FUNC_NONE, kdebug_vnode(vp), flags, 0, -3, 0); return 0; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 53)) | DBG_FUNC_START, wbp->cl_scmap, wbp->cl_number, flags, 0, 0); /* * if we have an fsync in progress, we don't want to allow any additional * sync/fsync/close(s) to occur until it finishes. * note that its possible for writes to continue to occur to this file * while we're waiting and also once the fsync starts to clean if we're * in the sparse map case */ while (wbp->cl_sparse_wait) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 97)) | DBG_FUNC_START, kdebug_vnode(vp), 0, 0, 0, 0); msleep((caddr_t)&wbp->cl_sparse_wait, &wbp->cl_lockw, PRIBIO + 1, "cluster_push_ext", NULL); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 97)) | DBG_FUNC_END, kdebug_vnode(vp), 0, 0, 0, 0); } if (flags & IO_SYNC) { my_sparse_wait = 1; wbp->cl_sparse_wait = 1; /* * this is an fsync (or equivalent)... we must wait for any existing async * cleaning operations to complete before we evaulate the current state * and finish cleaning... this insures that all writes issued before this * fsync actually get cleaned to the disk before this fsync returns */ while (wbp->cl_sparse_pushes) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 98)) | DBG_FUNC_START, kdebug_vnode(vp), 0, 0, 0, 0); msleep((caddr_t)&wbp->cl_sparse_pushes, &wbp->cl_lockw, PRIBIO + 1, "cluster_push_ext", NULL); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 98)) | DBG_FUNC_END, kdebug_vnode(vp), 0, 0, 0, 0); } } if (wbp->cl_scmap) { void *scmap; if (wbp->cl_sparse_pushes < SPARSE_PUSH_LIMIT) { scmap = wbp->cl_scmap; wbp->cl_scmap = NULL; wbp->cl_sparse_pushes++; lck_mtx_unlock(&wbp->cl_lockw); retval = sparse_cluster_push(wbp, &scmap, vp, ubc_getsize(vp), PUSH_ALL, flags, callback, callback_arg, FALSE); lck_mtx_lock(&wbp->cl_lockw); wbp->cl_sparse_pushes--; if (retval) { if (wbp->cl_scmap != NULL) { /* * panic("cluster_push_err: Expected NULL cl_scmap\n"); * * This can happen if we get an error from the underlying FS * e.g. ENOSPC, EPERM or EIO etc. We hope that these errors * are transient and the I/Os will succeed at a later point. * * The tricky part here is that a new sparse cluster has been * allocated and tracking a different set of dirty pages. So these * pages are not going to be pushed out with the next sparse_cluster_push. * An explicit msync or file close will, however, push the pages out. * * What if those calls still don't work? And so, during shutdown we keep * trying till we succeed... */ if (system_inshutdown) { if ((retval == ENOSPC) && (vp->v_mount->mnt_flag & (MNT_LOCAL | MNT_REMOVABLE)) == MNT_LOCAL) { os_atomic_inc(&cl_sparse_push_error, relaxed); } } else { vfs_drt_control(&scmap, 0); /* emit stats and free this memory. Dirty pages stay intact. */ scmap = NULL; } } else { wbp->cl_scmap = scmap; } } if (wbp->cl_sparse_wait && wbp->cl_sparse_pushes == 0) { wakeup((caddr_t)&wbp->cl_sparse_pushes); } } else { retval = sparse_cluster_push(wbp, &(wbp->cl_scmap), vp, ubc_getsize(vp), PUSH_ALL, flags, callback, callback_arg, FALSE); } local_err = retval; if (err) { *err = retval; } retval = 1; } else { retval = cluster_try_push(wbp, vp, ubc_getsize(vp), PUSH_ALL, flags, callback, callback_arg, &local_err, FALSE); if (err) { *err = local_err; } } lck_mtx_unlock(&wbp->cl_lockw); if (flags & IO_SYNC) { (void)vnode_waitforwrites(vp, 0, 0, 0, "cluster_push"); } if (my_sparse_wait) { /* * I'm the owner of the serialization token * clear it and wakeup anyone that is waiting * for me to finish */ lck_mtx_lock(&wbp->cl_lockw); wbp->cl_sparse_wait = 0; wakeup((caddr_t)&wbp->cl_sparse_wait); lck_mtx_unlock(&wbp->cl_lockw); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 53)) | DBG_FUNC_END, wbp->cl_scmap, wbp->cl_number, retval, local_err, 0); return retval; } __private_extern__ void cluster_release(struct ubc_info *ubc) { struct cl_writebehind *wbp; struct cl_readahead *rap; if ((wbp = ubc->cl_wbehind)) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 81)) | DBG_FUNC_START, ubc, wbp->cl_scmap, 0, 0, 0); if (wbp->cl_scmap) { vfs_drt_control(&(wbp->cl_scmap), 0); } lck_mtx_destroy(&wbp->cl_lockw, &cl_mtx_grp); zfree(cl_wr_zone, wbp); ubc->cl_wbehind = NULL; } else { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 81)) | DBG_FUNC_START, ubc, 0, 0, 0, 0); } if ((rap = ubc->cl_rahead)) { lck_mtx_destroy(&rap->cl_lockr, &cl_mtx_grp); zfree(cl_rd_zone, rap); ubc->cl_rahead = NULL; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 81)) | DBG_FUNC_END, ubc, rap, wbp, 0, 0); } static int cluster_try_push(struct cl_writebehind *wbp, vnode_t vp, off_t EOF, int push_flag, int io_flags, int (*callback)(buf_t, void *), void *callback_arg, int *err, boolean_t vm_initiated) { int cl_index; int cl_index1; int min_index; int cl_len; int cl_pushed = 0; struct cl_wextent l_clusters[MAX_CLUSTERS]; u_int max_cluster_pgcount; int error = 0; max_cluster_pgcount = MAX_CLUSTER_SIZE(vp) / PAGE_SIZE; /* * the write behind context exists and has * already been locked... */ if (wbp->cl_number == 0) { /* * no clusters to push * return number of empty slots */ return MAX_CLUSTERS; } /* * make a local 'sorted' copy of the clusters * and clear wbp->cl_number so that new clusters can * be developed */ for (cl_index = 0; cl_index < wbp->cl_number; cl_index++) { for (min_index = -1, cl_index1 = 0; cl_index1 < wbp->cl_number; cl_index1++) { if (wbp->cl_clusters[cl_index1].b_addr == wbp->cl_clusters[cl_index1].e_addr) { continue; } if (min_index == -1) { min_index = cl_index1; } else if (wbp->cl_clusters[cl_index1].b_addr < wbp->cl_clusters[min_index].b_addr) { min_index = cl_index1; } } if (min_index == -1) { break; } l_clusters[cl_index].b_addr = wbp->cl_clusters[min_index].b_addr; l_clusters[cl_index].e_addr = wbp->cl_clusters[min_index].e_addr; l_clusters[cl_index].io_flags = wbp->cl_clusters[min_index].io_flags; wbp->cl_clusters[min_index].b_addr = wbp->cl_clusters[min_index].e_addr; } wbp->cl_number = 0; cl_len = cl_index; /* skip switching to the sparse cluster mechanism if on diskimage */ if (((push_flag & PUSH_DELAY) && cl_len == MAX_CLUSTERS) && !(vp->v_mount->mnt_kern_flag & MNTK_VIRTUALDEV)) { int i; /* * determine if we appear to be writing the file sequentially * if not, by returning without having pushed any clusters * we will cause this vnode to be pushed into the sparse cluster mechanism * used for managing more random I/O patterns * * we know that we've got all clusters currently in use and the next write doesn't fit into one of them... * that's why we're in try_push with PUSH_DELAY... * * check to make sure that all the clusters except the last one are 'full'... and that each cluster * is adjacent to the next (i.e. we're looking for sequential writes) they were sorted above * so we can just make a simple pass through, up to, but not including the last one... * note that e_addr is not inclusive, so it will be equal to the b_addr of the next cluster if they * are sequential * * we let the last one be partial as long as it was adjacent to the previous one... * we need to do this to deal with multi-threaded servers that might write an I/O or 2 out * of order... if this occurs at the tail of the last cluster, we don't want to fall into the sparse cluster world... */ for (i = 0; i < MAX_CLUSTERS - 1; i++) { if ((l_clusters[i].e_addr - l_clusters[i].b_addr) != max_cluster_pgcount) { goto dont_try; } if (l_clusters[i].e_addr != l_clusters[i + 1].b_addr) { goto dont_try; } } } if (vm_initiated == TRUE) { lck_mtx_unlock(&wbp->cl_lockw); } for (cl_index = 0; cl_index < cl_len; cl_index++) { int flags; struct cl_extent cl; int retval; flags = io_flags & (IO_PASSIVE | IO_CLOSE); /* * try to push each cluster in turn... */ if (l_clusters[cl_index].io_flags & CLW_IONOCACHE) { flags |= IO_NOCACHE; } if (l_clusters[cl_index].io_flags & CLW_IOPASSIVE) { flags |= IO_PASSIVE; } if (push_flag & PUSH_SYNC) { flags |= IO_SYNC; } cl.b_addr = l_clusters[cl_index].b_addr; cl.e_addr = l_clusters[cl_index].e_addr; retval = cluster_push_now(vp, &cl, EOF, flags, callback, callback_arg, vm_initiated); if (retval == 0) { cl_pushed++; l_clusters[cl_index].b_addr = 0; l_clusters[cl_index].e_addr = 0; } else if (error == 0) { error = retval; } if (!(push_flag & PUSH_ALL)) { break; } } if (vm_initiated == TRUE) { lck_mtx_lock(&wbp->cl_lockw); } if (err) { *err = error; } dont_try: if (cl_len > cl_pushed) { /* * we didn't push all of the clusters, so * lets try to merge them back in to the vnode */ if ((MAX_CLUSTERS - wbp->cl_number) < (cl_len - cl_pushed)) { /* * we picked up some new clusters while we were trying to * push the old ones... this can happen because I've dropped * the vnode lock... the sum of the * leftovers plus the new cluster count exceeds our ability * to represent them, so switch to the sparse cluster mechanism * * collect the active public clusters... */ sparse_cluster_switch(wbp, vp, EOF, callback, callback_arg, vm_initiated); for (cl_index = 0, cl_index1 = 0; cl_index < cl_len; cl_index++) { if (l_clusters[cl_index].b_addr == l_clusters[cl_index].e_addr) { continue; } wbp->cl_clusters[cl_index1].b_addr = l_clusters[cl_index].b_addr; wbp->cl_clusters[cl_index1].e_addr = l_clusters[cl_index].e_addr; wbp->cl_clusters[cl_index1].io_flags = l_clusters[cl_index].io_flags; cl_index1++; } /* * update the cluster count */ wbp->cl_number = cl_index1; /* * and collect the original clusters that were moved into the * local storage for sorting purposes */ sparse_cluster_switch(wbp, vp, EOF, callback, callback_arg, vm_initiated); } else { /* * we've got room to merge the leftovers back in * just append them starting at the next 'hole' * represented by wbp->cl_number */ for (cl_index = 0, cl_index1 = wbp->cl_number; cl_index < cl_len; cl_index++) { if (l_clusters[cl_index].b_addr == l_clusters[cl_index].e_addr) { continue; } wbp->cl_clusters[cl_index1].b_addr = l_clusters[cl_index].b_addr; wbp->cl_clusters[cl_index1].e_addr = l_clusters[cl_index].e_addr; wbp->cl_clusters[cl_index1].io_flags = l_clusters[cl_index].io_flags; cl_index1++; } /* * update the cluster count */ wbp->cl_number = cl_index1; } } return MAX_CLUSTERS - wbp->cl_number; } static int cluster_push_now(vnode_t vp, struct cl_extent *cl, off_t EOF, int flags, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated) { upl_page_info_t *pl; upl_t upl; vm_offset_t upl_offset; int upl_size; off_t upl_f_offset; int pages_in_upl; int start_pg; int last_pg; int io_size; int io_flags; int upl_flags; int bflag; int size; int error = 0; int retval; kern_return_t kret; if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (flags & IO_SKIP_ENCRYPTION) { bflag |= CL_ENCRYPTED; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 51)) | DBG_FUNC_START, (int)cl->b_addr, (int)cl->e_addr, (int)EOF, flags, 0); if ((pages_in_upl = (int)(cl->e_addr - cl->b_addr)) == 0) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 51)) | DBG_FUNC_END, 1, 0, 0, 0, 0); return 0; } upl_size = pages_in_upl * PAGE_SIZE; upl_f_offset = (off_t)(cl->b_addr * PAGE_SIZE_64); if (upl_f_offset + upl_size >= EOF) { if (upl_f_offset >= EOF) { /* * must have truncated the file and missed * clearing a dangling cluster (i.e. it's completely * beyond the new EOF */ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 51)) | DBG_FUNC_END, 1, 1, 0, 0, 0); return 0; } size = (int)(EOF - upl_f_offset); upl_size = (size + (PAGE_SIZE - 1)) & ~PAGE_MASK; pages_in_upl = upl_size / PAGE_SIZE; } else { size = upl_size; } if (vm_initiated) { vnode_pageout(vp, NULL, (upl_offset_t)0, upl_f_offset, (upl_size_t)upl_size, UPL_MSYNC | UPL_VNODE_PAGER | UPL_KEEPCACHED, &error); return error; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 41)) | DBG_FUNC_START, upl_size, size, 0, 0, 0); /* * by asking for UPL_COPYOUT_FROM and UPL_RET_ONLY_DIRTY, we get the following desirable behavior * * - only pages that are currently dirty are returned... these are the ones we need to clean * - the hardware dirty bit is cleared when the page is gathered into the UPL... the software dirty bit is set * - if we have to abort the I/O for some reason, the software dirty bit is left set since we didn't clean the page * - when we commit the page, the software dirty bit is cleared... the hardware dirty bit is untouched so that if * someone dirties this page while the I/O is in progress, we don't lose track of the new state * * when the I/O completes, we no longer ask for an explicit clear of the DIRTY state (either soft or hard) */ if ((vp->v_flag & VNOCACHE_DATA) || (flags & IO_NOCACHE)) { upl_flags = UPL_COPYOUT_FROM | UPL_RET_ONLY_DIRTY | UPL_SET_LITE | UPL_WILL_BE_DUMPED; } else { upl_flags = UPL_COPYOUT_FROM | UPL_RET_ONLY_DIRTY | UPL_SET_LITE; } kret = ubc_create_upl_kernel(vp, upl_f_offset, upl_size, &upl, &pl, upl_flags, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { panic("cluster_push: failed to get pagelist"); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 41)) | DBG_FUNC_END, upl, upl_f_offset, 0, 0, 0); /* * since we only asked for the dirty pages back * it's possible that we may only get a few or even none, so... * before we start marching forward, we must make sure we know * where the last present page is in the UPL, otherwise we could * end up working with a freed upl due to the FREE_ON_EMPTY semantics * employed by commit_range and abort_range. */ for (last_pg = pages_in_upl - 1; last_pg >= 0; last_pg--) { if (upl_page_present(pl, last_pg)) { break; } } pages_in_upl = last_pg + 1; if (pages_in_upl == 0) { ubc_upl_abort(upl, 0); KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 51)) | DBG_FUNC_END, 1, 2, 0, 0, 0); return 0; } for (last_pg = 0; last_pg < pages_in_upl;) { /* * find the next dirty page in the UPL * this will become the first page in the * next I/O to generate */ for (start_pg = last_pg; start_pg < pages_in_upl; start_pg++) { if (upl_dirty_page(pl, start_pg)) { break; } if (upl_page_present(pl, start_pg)) { /* * RET_ONLY_DIRTY will return non-dirty 'precious' pages * just release these unchanged since we're not going * to steal them or change their state */ ubc_upl_abort_range(upl, start_pg * PAGE_SIZE, PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); } } if (start_pg >= pages_in_upl) { /* * done... no more dirty pages to push */ break; } if (start_pg > last_pg) { /* * skipped over some non-dirty pages */ size -= ((start_pg - last_pg) * PAGE_SIZE); } /* * find a range of dirty pages to write */ for (last_pg = start_pg; last_pg < pages_in_upl; last_pg++) { if (!upl_dirty_page(pl, last_pg)) { break; } } upl_offset = start_pg * PAGE_SIZE; io_size = min(size, (last_pg - start_pg) * PAGE_SIZE); io_flags = CL_THROTTLE | CL_COMMIT | CL_AGE | bflag; if (!(flags & IO_SYNC)) { io_flags |= CL_ASYNC; } if (flags & IO_CLOSE) { io_flags |= CL_CLOSE; } if (flags & IO_NOCACHE) { io_flags |= CL_NOCACHE; } retval = cluster_io(vp, upl, upl_offset, upl_f_offset + upl_offset, io_size, io_flags, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); if (error == 0 && retval) { error = retval; } size -= io_size; } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 51)) | DBG_FUNC_END, 1, 3, error, 0, 0); return error; } /* * sparse_cluster_switch is called with the write behind lock held */ static int sparse_cluster_switch(struct cl_writebehind *wbp, vnode_t vp, off_t EOF, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated) { int cl_index; int error = 0; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 78)) | DBG_FUNC_START, kdebug_vnode(vp), wbp->cl_scmap, wbp->cl_number, 0, 0); for (cl_index = 0; cl_index < wbp->cl_number; cl_index++) { int flags; struct cl_extent cl; for (cl.b_addr = wbp->cl_clusters[cl_index].b_addr; cl.b_addr < wbp->cl_clusters[cl_index].e_addr; cl.b_addr++) { if (ubc_page_op(vp, (off_t)(cl.b_addr * PAGE_SIZE_64), 0, NULL, &flags) == KERN_SUCCESS) { if (flags & UPL_POP_DIRTY) { cl.e_addr = cl.b_addr + 1; error = sparse_cluster_add(wbp, &(wbp->cl_scmap), vp, &cl, EOF, callback, callback_arg, vm_initiated); if (error) { break; } } } } } wbp->cl_number -= cl_index; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 78)) | DBG_FUNC_END, kdebug_vnode(vp), wbp->cl_scmap, wbp->cl_number, error, 0); return error; } /* * sparse_cluster_push must be called with the write-behind lock held if the scmap is * still associated with the write-behind context... however, if the scmap has been disassociated * from the write-behind context (the cluster_push case), the wb lock is not held */ static int sparse_cluster_push(struct cl_writebehind *wbp, void **scmap, vnode_t vp, off_t EOF, int push_flag, int io_flags, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated) { struct cl_extent cl; off_t offset; u_int length; void *l_scmap; int error = 0; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 79)) | DBG_FUNC_START, kdebug_vnode(vp), (*scmap), 0, push_flag, 0); if (push_flag & PUSH_ALL) { vfs_drt_control(scmap, 1); } l_scmap = *scmap; for (;;) { int retval; if (vfs_drt_get_cluster(scmap, &offset, &length) != KERN_SUCCESS) { /* * Not finding anything to push will return KERN_FAILURE. * Confusing since it isn't really a failure. But that's the * reason we don't set 'error' here like we do below. */ break; } if (vm_initiated == TRUE) { lck_mtx_unlock(&wbp->cl_lockw); } cl.b_addr = (daddr64_t)(offset / PAGE_SIZE_64); cl.e_addr = (daddr64_t)((offset + length) / PAGE_SIZE_64); retval = cluster_push_now(vp, &cl, EOF, io_flags, callback, callback_arg, vm_initiated); if (error == 0 && retval) { error = retval; } if (vm_initiated == TRUE) { lck_mtx_lock(&wbp->cl_lockw); if (*scmap != l_scmap) { break; } } if (error) { if (vfs_drt_mark_pages(scmap, offset, length, NULL) != KERN_SUCCESS) { panic("Failed to restore dirty state on failure"); } break; } if (!(push_flag & PUSH_ALL)) { break; } } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 79)) | DBG_FUNC_END, kdebug_vnode(vp), (*scmap), error, 0, 0); return error; } /* * sparse_cluster_add is called with the write behind lock held */ static int sparse_cluster_add(struct cl_writebehind *wbp, void **scmap, vnode_t vp, struct cl_extent *cl, off_t EOF, int (*callback)(buf_t, void *), void *callback_arg, boolean_t vm_initiated) { u_int new_dirty; u_int length; off_t offset; int error = 0; int push_flag = 0; /* Is this a valid value? */ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 80)) | DBG_FUNC_START, (*scmap), 0, cl->b_addr, (int)cl->e_addr, 0); offset = (off_t)(cl->b_addr * PAGE_SIZE_64); length = ((u_int)(cl->e_addr - cl->b_addr)) * PAGE_SIZE; while (vfs_drt_mark_pages(scmap, offset, length, &new_dirty) != KERN_SUCCESS) { /* * no room left in the map * only a partial update was done * push out some pages and try again */ if (vfs_get_scmap_push_behavior_internal(scmap, &push_flag)) { push_flag = 0; } error = sparse_cluster_push(wbp, scmap, vp, EOF, push_flag, 0, callback, callback_arg, vm_initiated); if (error) { break; } offset += (new_dirty * PAGE_SIZE_64); length -= (new_dirty * PAGE_SIZE); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 80)) | DBG_FUNC_END, kdebug_vnode(vp), (*scmap), error, 0, 0); return error; } static int cluster_align_phys_io(vnode_t vp, struct uio *uio, addr64_t usr_paddr, u_int32_t xsize, int flags, int (*callback)(buf_t, void *), void *callback_arg) { upl_page_info_t *pl; upl_t upl; addr64_t ubc_paddr; kern_return_t kret; int error = 0; int did_read = 0; int abort_flags; int upl_flags; int bflag; if (flags & IO_PASSIVE) { bflag = CL_PASSIVE; } else { bflag = 0; } if (flags & IO_NOCACHE) { bflag |= CL_NOCACHE; } upl_flags = UPL_SET_LITE; if (!(flags & CL_READ)) { /* * "write" operation: let the UPL subsystem know * that we intend to modify the buffer cache pages * we're gathering. */ upl_flags |= UPL_WILL_MODIFY; } else { /* * indicate that there is no need to pull the * mapping for this page... we're only going * to read from it, not modify it. */ upl_flags |= UPL_FILE_IO; } kret = ubc_create_upl_kernel(vp, uio->uio_offset & ~PAGE_MASK_64, PAGE_SIZE, &upl, &pl, upl_flags, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { return EINVAL; } if (!upl_valid_page(pl, 0)) { /* * issue a synchronous read to cluster_io */ error = cluster_io(vp, upl, 0, uio->uio_offset & ~PAGE_MASK_64, PAGE_SIZE, CL_READ | bflag, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); if (error) { ubc_upl_abort_range(upl, 0, PAGE_SIZE, UPL_ABORT_DUMP_PAGES | UPL_ABORT_FREE_ON_EMPTY); return error; } did_read = 1; } ubc_paddr = ((addr64_t)upl_phys_page(pl, 0) << PAGE_SHIFT) + (addr64_t)(uio->uio_offset & PAGE_MASK_64); /* * NOTE: There is no prototype for the following in BSD. It, and the definitions * of the defines for cppvPsrc, cppvPsnk, cppvFsnk, and cppvFsrc will be found in * osfmk/ppc/mappings.h. They are not included here because there appears to be no * way to do so without exporting them to kexts as well. */ if (flags & CL_READ) { // copypv(ubc_paddr, usr_paddr, xsize, cppvPsrc | cppvPsnk | cppvFsnk); /* Copy physical to physical and flush the destination */ copypv(ubc_paddr, usr_paddr, xsize, 2 | 1 | 4); /* Copy physical to physical and flush the destination */ } else { // copypv(usr_paddr, ubc_paddr, xsize, cppvPsrc | cppvPsnk | cppvFsrc); /* Copy physical to physical and flush the source */ copypv(usr_paddr, ubc_paddr, xsize, 2 | 1 | 8); /* Copy physical to physical and flush the source */ } if (!(flags & CL_READ) || (upl_valid_page(pl, 0) && upl_dirty_page(pl, 0))) { /* * issue a synchronous write to cluster_io */ error = cluster_io(vp, upl, 0, uio->uio_offset & ~PAGE_MASK_64, PAGE_SIZE, bflag, (buf_t)NULL, (struct clios *)NULL, callback, callback_arg); } if (error == 0) { uio_update(uio, (user_size_t)xsize); } if (did_read) { abort_flags = UPL_ABORT_FREE_ON_EMPTY; } else { abort_flags = UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_DUMP_PAGES; } ubc_upl_abort_range(upl, 0, PAGE_SIZE, abort_flags); return error; } int cluster_copy_upl_data(struct uio *uio, upl_t upl, int upl_offset, int *io_resid) { int pg_offset; int pg_index; int csize; int segflg; int retval = 0; int xsize; upl_page_info_t *pl; int dirty_count; xsize = *io_resid; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 34)) | DBG_FUNC_START, (int)uio->uio_offset, upl_offset, xsize, 0, 0); segflg = uio->uio_segflg; switch (segflg) { case UIO_USERSPACE32: case UIO_USERISPACE32: uio->uio_segflg = UIO_PHYS_USERSPACE32; break; case UIO_USERSPACE: case UIO_USERISPACE: uio->uio_segflg = UIO_PHYS_USERSPACE; break; case UIO_USERSPACE64: case UIO_USERISPACE64: uio->uio_segflg = UIO_PHYS_USERSPACE64; break; case UIO_SYSSPACE: uio->uio_segflg = UIO_PHYS_SYSSPACE; break; } pl = ubc_upl_pageinfo(upl); pg_index = upl_offset / PAGE_SIZE; pg_offset = upl_offset & PAGE_MASK; csize = min(PAGE_SIZE - pg_offset, xsize); dirty_count = 0; while (xsize && retval == 0) { addr64_t paddr; paddr = ((addr64_t)upl_phys_page(pl, pg_index) << PAGE_SHIFT) + pg_offset; if ((uio->uio_rw == UIO_WRITE) && (upl_dirty_page(pl, pg_index) == FALSE)) { dirty_count++; } retval = uiomove64(paddr, csize, uio); pg_index += 1; pg_offset = 0; xsize -= csize; csize = min(PAGE_SIZE, xsize); } *io_resid = xsize; uio->uio_segflg = segflg; if (dirty_count) { task_update_logical_writes(current_task(), (dirty_count * PAGE_SIZE), TASK_WRITE_DEFERRED, upl_lookup_vnode(upl)); } KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 34)) | DBG_FUNC_END, (int)uio->uio_offset, xsize, retval, segflg, 0); return retval; } int cluster_copy_ubc_data(vnode_t vp, struct uio *uio, int *io_resid, int mark_dirty) { return cluster_copy_ubc_data_internal(vp, uio, io_resid, mark_dirty, 1); } static int cluster_copy_ubc_data_internal(vnode_t vp, struct uio *uio, int *io_resid, int mark_dirty, int take_reference) { int segflg; int io_size; int xsize; int start_offset; int retval = 0; memory_object_control_t control; io_size = *io_resid; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 34)) | DBG_FUNC_START, (int)uio->uio_offset, io_size, mark_dirty, take_reference, 0); control = ubc_getobject(vp, UBC_FLAGS_NONE); if (control == MEMORY_OBJECT_CONTROL_NULL) { KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 34)) | DBG_FUNC_END, (int)uio->uio_offset, io_size, retval, 3, 0); return 0; } segflg = uio->uio_segflg; switch (segflg) { case UIO_USERSPACE32: case UIO_USERISPACE32: uio->uio_segflg = UIO_PHYS_USERSPACE32; break; case UIO_USERSPACE64: case UIO_USERISPACE64: uio->uio_segflg = UIO_PHYS_USERSPACE64; break; case UIO_USERSPACE: case UIO_USERISPACE: uio->uio_segflg = UIO_PHYS_USERSPACE; break; case UIO_SYSSPACE: uio->uio_segflg = UIO_PHYS_SYSSPACE; break; } if ((io_size = *io_resid)) { start_offset = (int)(uio->uio_offset & PAGE_MASK_64); xsize = (int)uio_resid(uio); retval = memory_object_control_uiomove(control, uio->uio_offset - start_offset, uio, start_offset, io_size, mark_dirty, take_reference); xsize -= uio_resid(uio); int num_bytes_copied = xsize; if (num_bytes_copied && uio_rw(uio)) { task_update_logical_writes(current_task(), num_bytes_copied, TASK_WRITE_DEFERRED, vp); } io_size -= xsize; } uio->uio_segflg = segflg; *io_resid = io_size; KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 34)) | DBG_FUNC_END, (int)uio->uio_offset, io_size, retval, 0x80000000 | segflg, 0); return retval; } int is_file_clean(vnode_t vp, off_t filesize) { off_t f_offset; int flags; int total_dirty = 0; for (f_offset = 0; f_offset < filesize; f_offset += PAGE_SIZE_64) { if (ubc_page_op(vp, f_offset, 0, NULL, &flags) == KERN_SUCCESS) { if (flags & UPL_POP_DIRTY) { total_dirty++; } } } if (total_dirty) { return EINVAL; } return 0; } /* * Dirty region tracking/clustering mechanism. * * This code (vfs_drt_*) provides a mechanism for tracking and clustering * dirty regions within a larger space (file). It is primarily intended to * support clustering in large files with many dirty areas. * * The implementation assumes that the dirty regions are pages. * * To represent dirty pages within the file, we store bit vectors in a * variable-size circular hash. */ /* * Bitvector size. This determines the number of pages we group in a * single hashtable entry. Each hashtable entry is aligned to this * size within the file. */ #define DRT_BITVECTOR_PAGES ((1024 * 256) / PAGE_SIZE) /* * File offset handling. * * DRT_ADDRESS_MASK is dependent on DRT_BITVECTOR_PAGES; * the correct formula is (~((DRT_BITVECTOR_PAGES * PAGE_SIZE) - 1)) */ #define DRT_ADDRESS_MASK (~((DRT_BITVECTOR_PAGES * PAGE_SIZE) - 1)) #define DRT_ALIGN_ADDRESS(addr) ((addr) & DRT_ADDRESS_MASK) /* * Hashtable address field handling. * * The low-order bits of the hashtable address are used to conserve * space. * * DRT_HASH_COUNT_MASK must be large enough to store the range * 0-DRT_BITVECTOR_PAGES inclusive, as well as have one value * to indicate that the bucket is actually unoccupied. */ #define DRT_HASH_GET_ADDRESS(scm, i) ((scm)->scm_hashtable[(i)].dhe_control & DRT_ADDRESS_MASK) #define DRT_HASH_SET_ADDRESS(scm, i, a) \ do { \ (scm)->scm_hashtable[(i)].dhe_control = \ ((scm)->scm_hashtable[(i)].dhe_control & ~DRT_ADDRESS_MASK) | DRT_ALIGN_ADDRESS(a); \ } while (0) #define DRT_HASH_COUNT_MASK 0x1ff #define DRT_HASH_GET_COUNT(scm, i) ((scm)->scm_hashtable[(i)].dhe_control & DRT_HASH_COUNT_MASK) #define DRT_HASH_SET_COUNT(scm, i, c) \ do { \ (scm)->scm_hashtable[(i)].dhe_control = \ ((scm)->scm_hashtable[(i)].dhe_control & ~DRT_HASH_COUNT_MASK) | ((c) & DRT_HASH_COUNT_MASK); \ } while (0) #define DRT_HASH_CLEAR(scm, i) \ do { \ (scm)->scm_hashtable[(i)].dhe_control = 0; \ } while (0) #define DRT_HASH_VACATE(scm, i) DRT_HASH_SET_COUNT((scm), (i), DRT_HASH_COUNT_MASK) #define DRT_HASH_VACANT(scm, i) (DRT_HASH_GET_COUNT((scm), (i)) == DRT_HASH_COUNT_MASK) #define DRT_HASH_COPY(oscm, oi, scm, i) \ do { \ (scm)->scm_hashtable[(i)].dhe_control = (oscm)->scm_hashtable[(oi)].dhe_control; \ DRT_BITVECTOR_COPY(oscm, oi, scm, i); \ } while(0); #if !defined(XNU_TARGET_OS_OSX) /* * Hash table moduli. * * Since the hashtable entry's size is dependent on the size of * the bitvector, and since the hashtable size is constrained to * both being prime and fitting within the desired allocation * size, these values need to be manually determined. * * For DRT_BITVECTOR_SIZE = 64, the entry size is 16 bytes. * * The small hashtable allocation is 4096 bytes, so the modulus is 251. * The large hashtable allocation is 32768 bytes, so the modulus is 2039. * The xlarge hashtable allocation is 131072 bytes, so the modulus is 8179. */ #define DRT_HASH_SMALL_MODULUS 251 #define DRT_HASH_LARGE_MODULUS 2039 #define DRT_HASH_XLARGE_MODULUS 8179 /* * Physical memory required before the large hash modulus is permitted. * * On small memory systems, the large hash modulus can lead to phsyical * memory starvation, so we avoid using it there. */ #define DRT_HASH_LARGE_MEMORY_REQUIRED (1024LL * 1024LL * 1024LL) /* 1GiB */ #define DRT_HASH_XLARGE_MEMORY_REQUIRED (8 * 1024LL * 1024LL * 1024LL) /* 8GiB */ #define DRT_SMALL_ALLOCATION 4096 /* 80 bytes spare */ #define DRT_LARGE_ALLOCATION 32768 /* 144 bytes spare */ #define DRT_XLARGE_ALLOCATION 131072 /* 208 bytes spare */ #else /* XNU_TARGET_OS_OSX */ /* * Hash table moduli. * * Since the hashtable entry's size is dependent on the size of * the bitvector, and since the hashtable size is constrained to * both being prime and fitting within the desired allocation * size, these values need to be manually determined. * * For DRT_BITVECTOR_SIZE = 64, the entry size is 16 bytes. * * The small hashtable allocation is 16384 bytes, so the modulus is 1019. * The large hashtable allocation is 131072 bytes, so the modulus is 8179. * The xlarge hashtable allocation is 524288 bytes, so the modulus is 32749. */ #define DRT_HASH_SMALL_MODULUS 1019 #define DRT_HASH_LARGE_MODULUS 8179 #define DRT_HASH_XLARGE_MODULUS 32749 /* * Physical memory required before the large hash modulus is permitted. * * On small memory systems, the large hash modulus can lead to phsyical * memory starvation, so we avoid using it there. */ #define DRT_HASH_LARGE_MEMORY_REQUIRED (4 * 1024LL * 1024LL * 1024LL) /* 4GiB */ #define DRT_HASH_XLARGE_MEMORY_REQUIRED (32 * 1024LL * 1024LL * 1024LL) /* 32GiB */ #define DRT_SMALL_ALLOCATION 16384 /* 80 bytes spare */ #define DRT_LARGE_ALLOCATION 131072 /* 208 bytes spare */ #define DRT_XLARGE_ALLOCATION 524288 /* 304 bytes spare */ #endif /* ! XNU_TARGET_OS_OSX */ /* *** nothing below here has secret dependencies on DRT_BITVECTOR_PAGES *** */ /* * Hashtable entry. */ struct vfs_drt_hashentry { u_int64_t dhe_control; /* * dhe_bitvector was declared as dhe_bitvector[DRT_BITVECTOR_PAGES / 32]; * DRT_BITVECTOR_PAGES is defined as ((1024 * 256) / PAGE_SIZE) * Since PAGE_SIZE is only known at boot time, * -define MAX_DRT_BITVECTOR_PAGES for smallest supported page size (4k) * -declare dhe_bitvector array for largest possible length */ #define MAX_DRT_BITVECTOR_PAGES (1024 * 256)/( 4 * 1024) u_int32_t dhe_bitvector[MAX_DRT_BITVECTOR_PAGES / 32]; }; /* * Hashtable bitvector handling. * * Bitvector fields are 32 bits long. */ #define DRT_HASH_SET_BIT(scm, i, bit) \ (scm)->scm_hashtable[(i)].dhe_bitvector[(bit) / 32] |= (1 << ((bit) % 32)) #define DRT_HASH_CLEAR_BIT(scm, i, bit) \ (scm)->scm_hashtable[(i)].dhe_bitvector[(bit) / 32] &= ~(1 << ((bit) % 32)) #define DRT_HASH_TEST_BIT(scm, i, bit) \ ((scm)->scm_hashtable[(i)].dhe_bitvector[(bit) / 32] & (1 << ((bit) % 32))) #define DRT_BITVECTOR_CLEAR(scm, i) \ bzero(&(scm)->scm_hashtable[(i)].dhe_bitvector[0], (MAX_DRT_BITVECTOR_PAGES / 32) * sizeof(u_int32_t)) #define DRT_BITVECTOR_COPY(oscm, oi, scm, i) \ bcopy(&(oscm)->scm_hashtable[(oi)].dhe_bitvector[0], \ &(scm)->scm_hashtable[(i)].dhe_bitvector[0], \ (MAX_DRT_BITVECTOR_PAGES / 32) * sizeof(u_int32_t)) /* * Dirty Region Tracking structure. * * The hashtable is allocated entirely inside the DRT structure. * * The hash is a simple circular prime modulus arrangement, the structure * is resized from small to large if it overflows. */ struct vfs_drt_clustermap { u_int32_t scm_magic; /* sanity/detection */ #define DRT_SCM_MAGIC 0x12020003 u_int32_t scm_modulus; /* current ring size */ u_int32_t scm_buckets; /* number of occupied buckets */ u_int32_t scm_lastclean; /* last entry we cleaned */ u_int32_t scm_iskips; /* number of slot skips */ struct vfs_drt_hashentry scm_hashtable[0]; }; #define DRT_HASH(scm, addr) ((addr) % (scm)->scm_modulus) #define DRT_HASH_NEXT(scm, addr) (((addr) + 1) % (scm)->scm_modulus) /* * Debugging codes and arguments. */ #define DRT_DEBUG_EMPTYFREE (FSDBG_CODE(DBG_FSRW, 82)) /* nil */ #define DRT_DEBUG_RETCLUSTER (FSDBG_CODE(DBG_FSRW, 83)) /* offset, length */ #define DRT_DEBUG_ALLOC (FSDBG_CODE(DBG_FSRW, 84)) /* copycount */ #define DRT_DEBUG_INSERT (FSDBG_CODE(DBG_FSRW, 85)) /* offset, iskip */ #define DRT_DEBUG_MARK (FSDBG_CODE(DBG_FSRW, 86)) /* offset, length, * dirty */ /* 0, setcount */ /* 1 (clean, no map) */ /* 2 (map alloc fail) */ /* 3, resid (partial) */ #define DRT_DEBUG_6 (FSDBG_CODE(DBG_FSRW, 87)) #define DRT_DEBUG_SCMDATA (FSDBG_CODE(DBG_FSRW, 88)) /* modulus, buckets, * lastclean, iskips */ static kern_return_t vfs_drt_alloc_map(struct vfs_drt_clustermap **cmapp); static kern_return_t vfs_drt_free_map(struct vfs_drt_clustermap *cmap); static kern_return_t vfs_drt_search_index(struct vfs_drt_clustermap *cmap, u_int64_t offset, int *indexp); static kern_return_t vfs_drt_get_index(struct vfs_drt_clustermap **cmapp, u_int64_t offset, int *indexp, int recursed); static kern_return_t vfs_drt_do_mark_pages( void **cmapp, u_int64_t offset, u_int length, u_int *setcountp, int dirty); static void vfs_drt_trace( struct vfs_drt_clustermap *cmap, int code, int arg1, int arg2, int arg3, int arg4); /* * Allocate and initialise a sparse cluster map. * * Will allocate a new map, resize or compact an existing map. * * XXX we should probably have at least one intermediate map size, * as the 1:16 ratio seems a bit drastic. */ static kern_return_t vfs_drt_alloc_map(struct vfs_drt_clustermap **cmapp) { struct vfs_drt_clustermap *cmap = NULL, *ocmap = NULL; kern_return_t kret = KERN_SUCCESS; u_int64_t offset = 0; u_int32_t i = 0; int modulus_size = 0, map_size = 0, active_buckets = 0, index = 0, copycount = 0; ocmap = NULL; if (cmapp != NULL) { ocmap = *cmapp; } /* * Decide on the size of the new map. */ if (ocmap == NULL) { modulus_size = DRT_HASH_SMALL_MODULUS; map_size = DRT_SMALL_ALLOCATION; } else { /* count the number of active buckets in the old map */ active_buckets = 0; for (i = 0; i < ocmap->scm_modulus; i++) { if (!DRT_HASH_VACANT(ocmap, i) && (DRT_HASH_GET_COUNT(ocmap, i) != 0)) { active_buckets++; } } /* * If we're currently using the small allocation, check to * see whether we should grow to the large one. */ if (ocmap->scm_modulus == DRT_HASH_SMALL_MODULUS) { /* * If the ring is nearly full and we are allowed to * use the large modulus, upgrade. */ if ((active_buckets > (DRT_HASH_SMALL_MODULUS - 5)) && (max_mem >= DRT_HASH_LARGE_MEMORY_REQUIRED)) { modulus_size = DRT_HASH_LARGE_MODULUS; map_size = DRT_LARGE_ALLOCATION; } else { modulus_size = DRT_HASH_SMALL_MODULUS; map_size = DRT_SMALL_ALLOCATION; } } else if (ocmap->scm_modulus == DRT_HASH_LARGE_MODULUS) { if ((active_buckets > (DRT_HASH_LARGE_MODULUS - 5)) && (max_mem >= DRT_HASH_XLARGE_MEMORY_REQUIRED)) { modulus_size = DRT_HASH_XLARGE_MODULUS; map_size = DRT_XLARGE_ALLOCATION; } else { /* * If the ring is completely full and we can't * expand, there's nothing useful for us to do. * Behave as though we had compacted into the new * array and return. */ return KERN_SUCCESS; } } else { /* already using the xlarge modulus */ modulus_size = DRT_HASH_XLARGE_MODULUS; map_size = DRT_XLARGE_ALLOCATION; /* * If the ring is completely full, there's * nothing useful for us to do. Behave as * though we had compacted into the new * array and return. */ if (active_buckets >= DRT_HASH_XLARGE_MODULUS) { return KERN_SUCCESS; } } } /* * Allocate and initialise the new map. */ kret = kmem_alloc(kernel_map, (vm_offset_t *)&cmap, map_size, KMA_DATA, VM_KERN_MEMORY_FILE); if (kret != KERN_SUCCESS) { return kret; } cmap->scm_magic = DRT_SCM_MAGIC; cmap->scm_modulus = modulus_size; cmap->scm_buckets = 0; cmap->scm_lastclean = 0; cmap->scm_iskips = 0; for (i = 0; i < cmap->scm_modulus; i++) { DRT_HASH_CLEAR(cmap, i); DRT_HASH_VACATE(cmap, i); DRT_BITVECTOR_CLEAR(cmap, i); } /* * If there's an old map, re-hash entries from it into the new map. */ copycount = 0; if (ocmap != NULL) { for (i = 0; i < ocmap->scm_modulus; i++) { /* skip empty buckets */ if (DRT_HASH_VACANT(ocmap, i) || (DRT_HASH_GET_COUNT(ocmap, i) == 0)) { continue; } /* get new index */ offset = DRT_HASH_GET_ADDRESS(ocmap, i); kret = vfs_drt_get_index(&cmap, offset, &index, 1); if (kret != KERN_SUCCESS) { /* XXX need to bail out gracefully here */ panic("vfs_drt: new cluster map mysteriously too small"); index = 0; } /* copy */ DRT_HASH_COPY(ocmap, i, cmap, index); copycount++; } } /* log what we've done */ vfs_drt_trace(cmap, DRT_DEBUG_ALLOC, copycount, 0, 0, 0); /* * It's important to ensure that *cmapp always points to * a valid map, so we must overwrite it before freeing * the old map. */ *cmapp = cmap; if (ocmap != NULL) { /* emit stats into trace buffer */ vfs_drt_trace(ocmap, DRT_DEBUG_SCMDATA, ocmap->scm_modulus, ocmap->scm_buckets, ocmap->scm_lastclean, ocmap->scm_iskips); vfs_drt_free_map(ocmap); } return KERN_SUCCESS; } /* * Free a sparse cluster map. */ static kern_return_t vfs_drt_free_map(struct vfs_drt_clustermap *cmap) { vm_size_t map_size = 0; if (cmap->scm_modulus == DRT_HASH_SMALL_MODULUS) { map_size = DRT_SMALL_ALLOCATION; } else if (cmap->scm_modulus == DRT_HASH_LARGE_MODULUS) { map_size = DRT_LARGE_ALLOCATION; } else if (cmap->scm_modulus == DRT_HASH_XLARGE_MODULUS) { map_size = DRT_XLARGE_ALLOCATION; } else { panic("vfs_drt_free_map: Invalid modulus %d", cmap->scm_modulus); } kmem_free(kernel_map, (vm_offset_t)cmap, map_size); return KERN_SUCCESS; } /* * Find the hashtable slot currently occupied by an entry for the supplied offset. */ static kern_return_t vfs_drt_search_index(struct vfs_drt_clustermap *cmap, u_int64_t offset, int *indexp) { int index; u_int32_t i; offset = DRT_ALIGN_ADDRESS(offset); index = DRT_HASH(cmap, offset); /* traverse the hashtable */ for (i = 0; i < cmap->scm_modulus; i++) { /* * If the slot is vacant, we can stop. */ if (DRT_HASH_VACANT(cmap, index)) { break; } /* * If the address matches our offset, we have success. */ if (DRT_HASH_GET_ADDRESS(cmap, index) == offset) { *indexp = index; return KERN_SUCCESS; } /* * Move to the next slot, try again. */ index = DRT_HASH_NEXT(cmap, index); } /* * It's not there. */ return KERN_FAILURE; } /* * Find the hashtable slot for the supplied offset. If we haven't allocated * one yet, allocate one and populate the address field. Note that it will * not have a nonzero page count and thus will still technically be free, so * in the case where we are called to clean pages, the slot will remain free. */ static kern_return_t vfs_drt_get_index(struct vfs_drt_clustermap **cmapp, u_int64_t offset, int *indexp, int recursed) { struct vfs_drt_clustermap *cmap; kern_return_t kret; u_int32_t index; u_int32_t i; cmap = *cmapp; /* look for an existing entry */ kret = vfs_drt_search_index(cmap, offset, indexp); if (kret == KERN_SUCCESS) { return kret; } /* need to allocate an entry */ offset = DRT_ALIGN_ADDRESS(offset); index = DRT_HASH(cmap, offset); /* scan from the index forwards looking for a vacant slot */ for (i = 0; i < cmap->scm_modulus; i++) { /* slot vacant? */ if (DRT_HASH_VACANT(cmap, index) || DRT_HASH_GET_COUNT(cmap, index) == 0) { cmap->scm_buckets++; if (index < cmap->scm_lastclean) { cmap->scm_lastclean = index; } DRT_HASH_SET_ADDRESS(cmap, index, offset); DRT_HASH_SET_COUNT(cmap, index, 0); DRT_BITVECTOR_CLEAR(cmap, index); *indexp = index; vfs_drt_trace(cmap, DRT_DEBUG_INSERT, (int)offset, i, 0, 0); return KERN_SUCCESS; } cmap->scm_iskips += i; index = DRT_HASH_NEXT(cmap, index); } /* * We haven't found a vacant slot, so the map is full. If we're not * already recursed, try reallocating/compacting it. */ if (recursed) { return KERN_FAILURE; } kret = vfs_drt_alloc_map(cmapp); if (kret == KERN_SUCCESS) { /* now try to insert again */ kret = vfs_drt_get_index(cmapp, offset, indexp, 1); } return kret; } /* * Implementation of set dirty/clean. * * In the 'clean' case, not finding a map is OK. */ static kern_return_t vfs_drt_do_mark_pages( void **private, u_int64_t offset, u_int length, u_int *setcountp, int dirty) { struct vfs_drt_clustermap *cmap, **cmapp; kern_return_t kret; int i, index, pgoff, pgcount, setcount, ecount; cmapp = (struct vfs_drt_clustermap **)private; cmap = *cmapp; vfs_drt_trace(cmap, DRT_DEBUG_MARK | DBG_FUNC_START, (int)offset, (int)length, dirty, 0); if (setcountp != NULL) { *setcountp = 0; } /* allocate a cluster map if we don't already have one */ if (cmap == NULL) { /* no cluster map, nothing to clean */ if (!dirty) { vfs_drt_trace(cmap, DRT_DEBUG_MARK | DBG_FUNC_END, 1, 0, 0, 0); return KERN_SUCCESS; } kret = vfs_drt_alloc_map(cmapp); if (kret != KERN_SUCCESS) { vfs_drt_trace(cmap, DRT_DEBUG_MARK | DBG_FUNC_END, 2, 0, 0, 0); return kret; } } setcount = 0; /* * Iterate over the length of the region. */ while (length > 0) { /* * Get the hashtable index for this offset. * * XXX this will add blank entries if we are clearing a range * that hasn't been dirtied. */ kret = vfs_drt_get_index(cmapp, offset, &index, 0); cmap = *cmapp; /* may have changed! */ /* this may be a partial-success return */ if (kret != KERN_SUCCESS) { if (setcountp != NULL) { *setcountp = setcount; } vfs_drt_trace(cmap, DRT_DEBUG_MARK | DBG_FUNC_END, 3, (int)length, 0, 0); return kret; } /* * Work out how many pages we're modifying in this * hashtable entry. */ pgoff = (int)((offset - DRT_ALIGN_ADDRESS(offset)) / PAGE_SIZE); pgcount = min((length / PAGE_SIZE), (DRT_BITVECTOR_PAGES - pgoff)); /* * Iterate over pages, dirty/clearing as we go. */ ecount = DRT_HASH_GET_COUNT(cmap, index); for (i = 0; i < pgcount; i++) { if (dirty) { if (!DRT_HASH_TEST_BIT(cmap, index, pgoff + i)) { if (ecount >= DRT_BITVECTOR_PAGES) { panic("ecount >= DRT_BITVECTOR_PAGES, cmap = %p, index = %d, bit = %d", cmap, index, pgoff + i); } DRT_HASH_SET_BIT(cmap, index, pgoff + i); ecount++; setcount++; } } else { if (DRT_HASH_TEST_BIT(cmap, index, pgoff + i)) { if (ecount <= 0) { panic("ecount <= 0, cmap = %p, index = %d, bit = %d", cmap, index, pgoff + i); } assert(ecount > 0); DRT_HASH_CLEAR_BIT(cmap, index, pgoff + i); ecount--; setcount++; } } } DRT_HASH_SET_COUNT(cmap, index, ecount); offset += pgcount * PAGE_SIZE; length -= pgcount * PAGE_SIZE; } if (setcountp != NULL) { *setcountp = setcount; } vfs_drt_trace(cmap, DRT_DEBUG_MARK | DBG_FUNC_END, 0, setcount, 0, 0); return KERN_SUCCESS; } /* * Mark a set of pages as dirty/clean. * * This is a public interface. * * cmapp * Pointer to storage suitable for holding a pointer. Note that * this must either be NULL or a value set by this function. * * size * Current file size in bytes. * * offset * Offset of the first page to be marked as dirty, in bytes. Must be * page-aligned. * * length * Length of dirty region, in bytes. Must be a multiple of PAGE_SIZE. * * setcountp * Number of pages newly marked dirty by this call (optional). * * Returns KERN_SUCCESS if all the pages were successfully marked. */ static kern_return_t vfs_drt_mark_pages(void **cmapp, off_t offset, u_int length, u_int *setcountp) { /* XXX size unused, drop from interface */ return vfs_drt_do_mark_pages(cmapp, offset, length, setcountp, 1); } #if 0 static kern_return_t vfs_drt_unmark_pages(void **cmapp, off_t offset, u_int length) { return vfs_drt_do_mark_pages(cmapp, offset, length, NULL, 0); } #endif /* * Get a cluster of dirty pages. * * This is a public interface. * * cmapp * Pointer to storage managed by drt_mark_pages. Note that this must * be NULL or a value set by drt_mark_pages. * * offsetp * Returns the byte offset into the file of the first page in the cluster. * * lengthp * Returns the length in bytes of the cluster of dirty pages. * * Returns success if a cluster was found. If KERN_FAILURE is returned, there * are no dirty pages meeting the minmum size criteria. Private storage will * be released if there are no more dirty pages left in the map * */ static kern_return_t vfs_drt_get_cluster(void **cmapp, off_t *offsetp, u_int *lengthp) { struct vfs_drt_clustermap *cmap; u_int64_t offset; u_int length; u_int32_t j; int index, i, fs, ls; /* sanity */ if ((cmapp == NULL) || (*cmapp == NULL)) { return KERN_FAILURE; } cmap = *cmapp; /* walk the hashtable */ for (offset = 0, j = 0; j < cmap->scm_modulus; offset += (DRT_BITVECTOR_PAGES * PAGE_SIZE), j++) { index = DRT_HASH(cmap, offset); if (DRT_HASH_VACANT(cmap, index) || (DRT_HASH_GET_COUNT(cmap, index) == 0)) { continue; } /* scan the bitfield for a string of bits */ fs = -1; for (i = 0; i < DRT_BITVECTOR_PAGES; i++) { if (DRT_HASH_TEST_BIT(cmap, index, i)) { fs = i; break; } } if (fs == -1) { /* didn't find any bits set */ panic("vfs_drt: entry summary count > 0 but no bits set in map, cmap = %p, index = %d, count = %lld", cmap, index, DRT_HASH_GET_COUNT(cmap, index)); } for (ls = 0; i < DRT_BITVECTOR_PAGES; i++, ls++) { if (!DRT_HASH_TEST_BIT(cmap, index, i)) { break; } } /* compute offset and length, mark pages clean */ offset = DRT_HASH_GET_ADDRESS(cmap, index) + (PAGE_SIZE * fs); length = ls * PAGE_SIZE; vfs_drt_do_mark_pages(cmapp, offset, length, NULL, 0); cmap->scm_lastclean = index; /* return successful */ *offsetp = (off_t)offset; *lengthp = length; vfs_drt_trace(cmap, DRT_DEBUG_RETCLUSTER, (int)offset, (int)length, 0, 0); return KERN_SUCCESS; } /* * We didn't find anything... hashtable is empty * emit stats into trace buffer and * then free it */ vfs_drt_trace(cmap, DRT_DEBUG_SCMDATA, cmap->scm_modulus, cmap->scm_buckets, cmap->scm_lastclean, cmap->scm_iskips); vfs_drt_free_map(cmap); *cmapp = NULL; return KERN_FAILURE; } static kern_return_t vfs_drt_control(void **cmapp, int op_type) { struct vfs_drt_clustermap *cmap; /* sanity */ if ((cmapp == NULL) || (*cmapp == NULL)) { return KERN_FAILURE; } cmap = *cmapp; switch (op_type) { case 0: /* emit stats into trace buffer */ vfs_drt_trace(cmap, DRT_DEBUG_SCMDATA, cmap->scm_modulus, cmap->scm_buckets, cmap->scm_lastclean, cmap->scm_iskips); vfs_drt_free_map(cmap); *cmapp = NULL; break; case 1: cmap->scm_lastclean = 0; break; } return KERN_SUCCESS; } /* * Emit a summary of the state of the clustermap into the trace buffer * along with some caller-provided data. */ #if KDEBUG static void vfs_drt_trace(__unused struct vfs_drt_clustermap *cmap, int code, int arg1, int arg2, int arg3, int arg4) { KERNEL_DEBUG(code, arg1, arg2, arg3, arg4, 0); } #else static void vfs_drt_trace(__unused struct vfs_drt_clustermap *cmap, __unused int code, __unused int arg1, __unused int arg2, __unused int arg3, __unused int arg4) { } #endif #if 0 /* * Perform basic sanity check on the hash entry summary count * vs. the actual bits set in the entry. */ static void vfs_drt_sanity(struct vfs_drt_clustermap *cmap) { int index, i; int bits_on; for (index = 0; index < cmap->scm_modulus; index++) { if (DRT_HASH_VACANT(cmap, index)) { continue; } for (bits_on = 0, i = 0; i < DRT_BITVECTOR_PAGES; i++) { if (DRT_HASH_TEST_BIT(cmap, index, i)) { bits_on++; } } if (bits_on != DRT_HASH_GET_COUNT(cmap, index)) { panic("bits_on = %d, index = %d", bits_on, index); } } } #endif /* * Internal interface only. */ static kern_return_t vfs_get_scmap_push_behavior_internal(void **cmapp, int *push_flag) { struct vfs_drt_clustermap *cmap; /* sanity */ if ((cmapp == NULL) || (*cmapp == NULL) || (push_flag == NULL)) { return KERN_FAILURE; } cmap = *cmapp; if (cmap->scm_modulus == DRT_HASH_XLARGE_MODULUS) { /* * If we have a full xlarge sparse cluster, * we push it out all at once so the cluster * map can be available to absorb more I/Os. * This is done on large memory configs so * the small I/Os don't interfere with the * pro workloads. */ *push_flag = PUSH_ALL; } return KERN_SUCCESS; }