2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #include <linux/stddef.h>
20 #include <linux/errno.h>
21 #include <linux/gfp.h>
22 #include <linux/pagemap.h>
23 #include <linux/init.h>
24 #include <linux/vmalloc.h>
25 #include <linux/bio.h>
26 #include <linux/sysctl.h>
27 #include <linux/proc_fs.h>
28 #include <linux/workqueue.h>
29 #include <linux/percpu.h>
30 #include <linux/blkdev.h>
31 #include <linux/hash.h>
32 #include <linux/kthread.h>
33 #include <linux/migrate.h>
34 #include <linux/backing-dev.h>
35 #include <linux/freezer.h>
36 #include <linux/list_sort.h>
42 #include "xfs_dmapi.h"
43 #include "xfs_mount.h"
44 #include "xfs_trace.h"
46 static kmem_zone_t *xfs_buf_zone;
47 STATIC int xfsbufd(void *);
48 STATIC int xfsbufd_wakeup(struct shrinker *, int, gfp_t);
49 STATIC void xfs_buf_delwri_queue(xfs_buf_t *, int);
50 static struct shrinker xfs_buf_shake = {
51 .shrink = xfsbufd_wakeup,
52 .seeks = DEFAULT_SEEKS,
55 static struct workqueue_struct *xfslogd_workqueue;
56 struct workqueue_struct *xfsdatad_workqueue;
57 struct workqueue_struct *xfsconvertd_workqueue;
59 #ifdef XFS_BUF_LOCK_TRACKING
60 # define XB_SET_OWNER(bp) ((bp)->b_last_holder = current->pid)
61 # define XB_CLEAR_OWNER(bp) ((bp)->b_last_holder = -1)
62 # define XB_GET_OWNER(bp) ((bp)->b_last_holder)
64 # define XB_SET_OWNER(bp) do { } while (0)
65 # define XB_CLEAR_OWNER(bp) do { } while (0)
66 # define XB_GET_OWNER(bp) do { } while (0)
69 #define xb_to_gfp(flags) \
70 ((((flags) & XBF_READ_AHEAD) ? __GFP_NORETRY : \
71 ((flags) & XBF_DONT_BLOCK) ? GFP_NOFS : GFP_KERNEL) | __GFP_NOWARN)
73 #define xb_to_km(flags) \
74 (((flags) & XBF_DONT_BLOCK) ? KM_NOFS : KM_SLEEP)
76 #define xfs_buf_allocate(flags) \
77 kmem_zone_alloc(xfs_buf_zone, xb_to_km(flags))
78 #define xfs_buf_deallocate(bp) \
79 kmem_zone_free(xfs_buf_zone, (bp));
86 * Return true if the buffer is vmapped.
88 * The XBF_MAPPED flag is set if the buffer should be mapped, but the
89 * code is clever enough to know it doesn't have to map a single page,
90 * so the check has to be both for XBF_MAPPED and bp->b_page_count > 1.
92 return (bp->b_flags & XBF_MAPPED) && bp->b_page_count > 1;
99 return (bp->b_page_count * PAGE_SIZE) - bp->b_offset;
103 * Page Region interfaces.
105 * For pages in filesystems where the blocksize is smaller than the
106 * pagesize, we use the page->private field (long) to hold a bitmap
107 * of uptodate regions within the page.
109 * Each such region is "bytes per page / bits per long" bytes long.
111 * NBPPR == number-of-bytes-per-page-region
112 * BTOPR == bytes-to-page-region (rounded up)
113 * BTOPRT == bytes-to-page-region-truncated (rounded down)
115 #if (BITS_PER_LONG == 32)
116 #define PRSHIFT (PAGE_CACHE_SHIFT - 5) /* (32 == 1<<5) */
117 #elif (BITS_PER_LONG == 64)
118 #define PRSHIFT (PAGE_CACHE_SHIFT - 6) /* (64 == 1<<6) */
120 #error BITS_PER_LONG must be 32 or 64
122 #define NBPPR (PAGE_CACHE_SIZE/BITS_PER_LONG)
123 #define BTOPR(b) (((unsigned int)(b) + (NBPPR - 1)) >> PRSHIFT)
124 #define BTOPRT(b) (((unsigned int)(b) >> PRSHIFT))
134 first = BTOPR(offset);
135 final = BTOPRT(offset + length - 1);
136 first = min(first, final);
139 mask <<= BITS_PER_LONG - (final - first);
140 mask >>= BITS_PER_LONG - (final);
142 ASSERT(offset + length <= PAGE_CACHE_SIZE);
143 ASSERT((final - first) < BITS_PER_LONG && (final - first) >= 0);
154 set_page_private(page,
155 page_private(page) | page_region_mask(offset, length));
156 if (page_private(page) == ~0UL)
157 SetPageUptodate(page);
166 unsigned long mask = page_region_mask(offset, length);
168 return (mask && (page_private(page) & mask) == mask);
172 * Internal xfs_buf_t object manipulation
178 xfs_buftarg_t *target,
179 xfs_off_t range_base,
181 xfs_buf_flags_t flags)
184 * We don't want certain flags to appear in b_flags.
186 flags &= ~(XBF_LOCK|XBF_MAPPED|XBF_DONT_BLOCK|XBF_READ_AHEAD);
188 memset(bp, 0, sizeof(xfs_buf_t));
189 atomic_set(&bp->b_hold, 1);
190 init_completion(&bp->b_iowait);
191 INIT_LIST_HEAD(&bp->b_list);
192 INIT_LIST_HEAD(&bp->b_hash_list);
193 init_MUTEX_LOCKED(&bp->b_sema); /* held, no waiters */
195 bp->b_target = target;
196 bp->b_file_offset = range_base;
198 * Set buffer_length and count_desired to the same value initially.
199 * I/O routines should use count_desired, which will be the same in
200 * most cases but may be reset (e.g. XFS recovery).
202 bp->b_buffer_length = bp->b_count_desired = range_length;
204 bp->b_bn = XFS_BUF_DADDR_NULL;
205 atomic_set(&bp->b_pin_count, 0);
206 init_waitqueue_head(&bp->b_waiters);
208 XFS_STATS_INC(xb_create);
210 trace_xfs_buf_init(bp, _RET_IP_);
214 * Allocate a page array capable of holding a specified number
215 * of pages, and point the page buf at it.
221 xfs_buf_flags_t flags)
223 /* Make sure that we have a page list */
224 if (bp->b_pages == NULL) {
225 bp->b_offset = xfs_buf_poff(bp->b_file_offset);
226 bp->b_page_count = page_count;
227 if (page_count <= XB_PAGES) {
228 bp->b_pages = bp->b_page_array;
230 bp->b_pages = kmem_alloc(sizeof(struct page *) *
231 page_count, xb_to_km(flags));
232 if (bp->b_pages == NULL)
235 memset(bp->b_pages, 0, sizeof(struct page *) * page_count);
241 * Frees b_pages if it was allocated.
247 if (bp->b_pages != bp->b_page_array) {
248 kmem_free(bp->b_pages);
254 * Releases the specified buffer.
256 * The modification state of any associated pages is left unchanged.
257 * The buffer most not be on any hash - use xfs_buf_rele instead for
258 * hashed and refcounted buffers
264 trace_xfs_buf_free(bp, _RET_IP_);
266 ASSERT(list_empty(&bp->b_hash_list));
268 if (bp->b_flags & (_XBF_PAGE_CACHE|_XBF_PAGES)) {
271 if (xfs_buf_is_vmapped(bp))
272 vm_unmap_ram(bp->b_addr - bp->b_offset,
275 for (i = 0; i < bp->b_page_count; i++) {
276 struct page *page = bp->b_pages[i];
278 if (bp->b_flags & _XBF_PAGE_CACHE)
279 ASSERT(!PagePrivate(page));
280 page_cache_release(page);
283 _xfs_buf_free_pages(bp);
284 xfs_buf_deallocate(bp);
288 * Finds all pages for buffer in question and builds it's page list.
291 _xfs_buf_lookup_pages(
295 struct address_space *mapping = bp->b_target->bt_mapping;
296 size_t blocksize = bp->b_target->bt_bsize;
297 size_t size = bp->b_count_desired;
298 size_t nbytes, offset;
299 gfp_t gfp_mask = xb_to_gfp(flags);
300 unsigned short page_count, i;
305 end = bp->b_file_offset + bp->b_buffer_length;
306 page_count = xfs_buf_btoc(end) - xfs_buf_btoct(bp->b_file_offset);
308 error = _xfs_buf_get_pages(bp, page_count, flags);
311 bp->b_flags |= _XBF_PAGE_CACHE;
313 offset = bp->b_offset;
314 first = bp->b_file_offset >> PAGE_CACHE_SHIFT;
316 for (i = 0; i < bp->b_page_count; i++) {
321 page = find_or_create_page(mapping, first + i, gfp_mask);
322 if (unlikely(page == NULL)) {
323 if (flags & XBF_READ_AHEAD) {
324 bp->b_page_count = i;
325 for (i = 0; i < bp->b_page_count; i++)
326 unlock_page(bp->b_pages[i]);
331 * This could deadlock.
333 * But until all the XFS lowlevel code is revamped to
334 * handle buffer allocation failures we can't do much.
336 if (!(++retries % 100))
338 "XFS: possible memory allocation "
339 "deadlock in %s (mode:0x%x)\n",
342 XFS_STATS_INC(xb_page_retries);
343 xfsbufd_wakeup(NULL, 0, gfp_mask);
344 congestion_wait(BLK_RW_ASYNC, HZ/50);
348 XFS_STATS_INC(xb_page_found);
350 nbytes = min_t(size_t, size, PAGE_CACHE_SIZE - offset);
353 ASSERT(!PagePrivate(page));
354 if (!PageUptodate(page)) {
356 if (blocksize >= PAGE_CACHE_SIZE) {
357 if (flags & XBF_READ)
358 bp->b_flags |= _XBF_PAGE_LOCKED;
359 } else if (!PagePrivate(page)) {
360 if (test_page_region(page, offset, nbytes))
365 bp->b_pages[i] = page;
369 if (!(bp->b_flags & _XBF_PAGE_LOCKED)) {
370 for (i = 0; i < bp->b_page_count; i++)
371 unlock_page(bp->b_pages[i]);
374 if (page_count == bp->b_page_count)
375 bp->b_flags |= XBF_DONE;
381 * Map buffer into kernel address-space if nessecary.
388 /* A single page buffer is always mappable */
389 if (bp->b_page_count == 1) {
390 bp->b_addr = page_address(bp->b_pages[0]) + bp->b_offset;
391 bp->b_flags |= XBF_MAPPED;
392 } else if (flags & XBF_MAPPED) {
393 bp->b_addr = vm_map_ram(bp->b_pages, bp->b_page_count,
395 if (unlikely(bp->b_addr == NULL))
397 bp->b_addr += bp->b_offset;
398 bp->b_flags |= XBF_MAPPED;
405 * Finding and Reading Buffers
409 * Look up, and creates if absent, a lockable buffer for
410 * a given range of an inode. The buffer is returned
411 * locked. If other overlapping buffers exist, they are
412 * released before the new buffer is created and locked,
413 * which may imply that this call will block until those buffers
414 * are unlocked. No I/O is implied by this call.
418 xfs_buftarg_t *btp, /* block device target */
419 xfs_off_t ioff, /* starting offset of range */
420 size_t isize, /* length of range */
421 xfs_buf_flags_t flags,
424 xfs_off_t range_base;
429 range_base = (ioff << BBSHIFT);
430 range_length = (isize << BBSHIFT);
432 /* Check for IOs smaller than the sector size / not sector aligned */
433 ASSERT(!(range_length < (1 << btp->bt_sshift)));
434 ASSERT(!(range_base & (xfs_off_t)btp->bt_smask));
436 hash = &btp->bt_hash[hash_long((unsigned long)ioff, btp->bt_hashshift)];
438 spin_lock(&hash->bh_lock);
440 list_for_each_entry_safe(bp, n, &hash->bh_list, b_hash_list) {
441 ASSERT(btp == bp->b_target);
442 if (bp->b_file_offset == range_base &&
443 bp->b_buffer_length == range_length) {
445 * If we look at something, bring it to the
446 * front of the list for next time.
448 atomic_inc(&bp->b_hold);
449 list_move(&bp->b_hash_list, &hash->bh_list);
456 _xfs_buf_initialize(new_bp, btp, range_base,
457 range_length, flags);
458 new_bp->b_hash = hash;
459 list_add(&new_bp->b_hash_list, &hash->bh_list);
461 XFS_STATS_INC(xb_miss_locked);
464 spin_unlock(&hash->bh_lock);
468 spin_unlock(&hash->bh_lock);
470 /* Attempt to get the semaphore without sleeping,
471 * if this does not work then we need to drop the
472 * spinlock and do a hard attempt on the semaphore.
474 if (down_trylock(&bp->b_sema)) {
475 if (!(flags & XBF_TRYLOCK)) {
476 /* wait for buffer ownership */
478 XFS_STATS_INC(xb_get_locked_waited);
480 /* We asked for a trylock and failed, no need
481 * to look at file offset and length here, we
482 * know that this buffer at least overlaps our
483 * buffer and is locked, therefore our buffer
484 * either does not exist, or is this buffer.
487 XFS_STATS_INC(xb_busy_locked);
495 if (bp->b_flags & XBF_STALE) {
496 ASSERT((bp->b_flags & _XBF_DELWRI_Q) == 0);
497 bp->b_flags &= XBF_MAPPED;
500 trace_xfs_buf_find(bp, flags, _RET_IP_);
501 XFS_STATS_INC(xb_get_locked);
506 * Assembles a buffer covering the specified range.
507 * Storage in memory for all portions of the buffer will be allocated,
508 * although backing storage may not be.
512 xfs_buftarg_t *target,/* target for buffer */
513 xfs_off_t ioff, /* starting offset of range */
514 size_t isize, /* length of range */
515 xfs_buf_flags_t flags)
517 xfs_buf_t *bp, *new_bp;
520 new_bp = xfs_buf_allocate(flags);
521 if (unlikely(!new_bp))
524 bp = _xfs_buf_find(target, ioff, isize, flags, new_bp);
526 error = _xfs_buf_lookup_pages(bp, flags);
530 xfs_buf_deallocate(new_bp);
531 if (unlikely(bp == NULL))
535 for (i = 0; i < bp->b_page_count; i++)
536 mark_page_accessed(bp->b_pages[i]);
538 if (!(bp->b_flags & XBF_MAPPED)) {
539 error = _xfs_buf_map_pages(bp, flags);
540 if (unlikely(error)) {
541 printk(KERN_WARNING "%s: failed to map pages\n",
547 XFS_STATS_INC(xb_get);
550 * Always fill in the block number now, the mapped cases can do
551 * their own overlay of this later.
554 bp->b_count_desired = bp->b_buffer_length;
556 trace_xfs_buf_get(bp, flags, _RET_IP_);
560 if (flags & (XBF_LOCK | XBF_TRYLOCK))
569 xfs_buf_flags_t flags)
573 ASSERT(!(flags & (XBF_DELWRI|XBF_WRITE)));
574 ASSERT(bp->b_bn != XFS_BUF_DADDR_NULL);
576 bp->b_flags &= ~(XBF_WRITE | XBF_ASYNC | XBF_DELWRI | \
577 XBF_READ_AHEAD | _XBF_RUN_QUEUES);
578 bp->b_flags |= flags & (XBF_READ | XBF_ASYNC | \
579 XBF_READ_AHEAD | _XBF_RUN_QUEUES);
581 status = xfs_buf_iorequest(bp);
582 if (!status && !(flags & XBF_ASYNC))
583 status = xfs_buf_iowait(bp);
589 xfs_buftarg_t *target,
592 xfs_buf_flags_t flags)
598 bp = xfs_buf_get(target, ioff, isize, flags);
600 trace_xfs_buf_read(bp, flags, _RET_IP_);
602 if (!XFS_BUF_ISDONE(bp)) {
603 XFS_STATS_INC(xb_get_read);
604 _xfs_buf_read(bp, flags);
605 } else if (flags & XBF_ASYNC) {
607 * Read ahead call which is already satisfied,
612 /* We do not want read in the flags */
613 bp->b_flags &= ~XBF_READ;
620 if (flags & (XBF_LOCK | XBF_TRYLOCK))
627 * If we are not low on memory then do the readahead in a deadlock
632 xfs_buftarg_t *target,
635 xfs_buf_flags_t flags)
637 struct backing_dev_info *bdi;
639 bdi = target->bt_mapping->backing_dev_info;
640 if (bdi_read_congested(bdi))
643 flags |= (XBF_TRYLOCK|XBF_ASYNC|XBF_READ_AHEAD);
644 xfs_buf_read(target, ioff, isize, flags);
650 xfs_buftarg_t *target)
654 bp = xfs_buf_allocate(0);
656 _xfs_buf_initialize(bp, target, 0, len, 0);
660 static inline struct page *
664 if ((!is_vmalloc_addr(addr))) {
665 return virt_to_page(addr);
667 return vmalloc_to_page(addr);
672 xfs_buf_associate_memory(
679 unsigned long pageaddr;
680 unsigned long offset;
684 pageaddr = (unsigned long)mem & PAGE_CACHE_MASK;
685 offset = (unsigned long)mem - pageaddr;
686 buflen = PAGE_CACHE_ALIGN(len + offset);
687 page_count = buflen >> PAGE_CACHE_SHIFT;
689 /* Free any previous set of page pointers */
691 _xfs_buf_free_pages(bp);
696 rval = _xfs_buf_get_pages(bp, page_count, XBF_DONT_BLOCK);
700 bp->b_offset = offset;
702 for (i = 0; i < bp->b_page_count; i++) {
703 bp->b_pages[i] = mem_to_page((void *)pageaddr);
704 pageaddr += PAGE_CACHE_SIZE;
707 bp->b_count_desired = len;
708 bp->b_buffer_length = buflen;
709 bp->b_flags |= XBF_MAPPED;
710 bp->b_flags &= ~_XBF_PAGE_LOCKED;
718 xfs_buftarg_t *target)
720 unsigned long page_count = PAGE_ALIGN(len) >> PAGE_SHIFT;
724 bp = xfs_buf_allocate(0);
725 if (unlikely(bp == NULL))
727 _xfs_buf_initialize(bp, target, 0, len, 0);
729 error = _xfs_buf_get_pages(bp, page_count, 0);
733 for (i = 0; i < page_count; i++) {
734 bp->b_pages[i] = alloc_page(GFP_KERNEL);
738 bp->b_flags |= _XBF_PAGES;
740 error = _xfs_buf_map_pages(bp, XBF_MAPPED);
741 if (unlikely(error)) {
742 printk(KERN_WARNING "%s: failed to map pages\n",
749 trace_xfs_buf_get_noaddr(bp, _RET_IP_);
754 __free_page(bp->b_pages[i]);
755 _xfs_buf_free_pages(bp);
757 xfs_buf_deallocate(bp);
763 * Increment reference count on buffer, to hold the buffer concurrently
764 * with another thread which may release (free) the buffer asynchronously.
765 * Must hold the buffer already to call this function.
771 trace_xfs_buf_hold(bp, _RET_IP_);
772 atomic_inc(&bp->b_hold);
776 * Releases a hold on the specified buffer. If the
777 * the hold count is 1, calls xfs_buf_free.
783 xfs_bufhash_t *hash = bp->b_hash;
785 trace_xfs_buf_rele(bp, _RET_IP_);
787 if (unlikely(!hash)) {
788 ASSERT(!bp->b_relse);
789 if (atomic_dec_and_test(&bp->b_hold))
794 ASSERT(atomic_read(&bp->b_hold) > 0);
795 if (atomic_dec_and_lock(&bp->b_hold, &hash->bh_lock)) {
797 atomic_inc(&bp->b_hold);
798 spin_unlock(&hash->bh_lock);
799 (*(bp->b_relse)) (bp);
800 } else if (bp->b_flags & XBF_FS_MANAGED) {
801 spin_unlock(&hash->bh_lock);
803 ASSERT(!(bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)));
804 list_del_init(&bp->b_hash_list);
805 spin_unlock(&hash->bh_lock);
813 * Mutual exclusion on buffers. Locking model:
815 * Buffers associated with inodes for which buffer locking
816 * is not enabled are not protected by semaphores, and are
817 * assumed to be exclusively owned by the caller. There is a
818 * spinlock in the buffer, used by the caller when concurrent
819 * access is possible.
823 * Locks a buffer object, if it is not already locked.
824 * Note that this in no way locks the underlying pages, so it is only
825 * useful for synchronizing concurrent use of buffer objects, not for
826 * synchronizing independent access to the underlying pages.
834 locked = down_trylock(&bp->b_sema) == 0;
838 trace_xfs_buf_cond_lock(bp, _RET_IP_);
839 return locked ? 0 : -EBUSY;
846 return bp->b_sema.count;
850 * Locks a buffer object.
851 * Note that this in no way locks the underlying pages, so it is only
852 * useful for synchronizing concurrent use of buffer objects, not for
853 * synchronizing independent access to the underlying pages.
855 * If we come across a stale, pinned, locked buffer, we know that we
856 * are being asked to lock a buffer that has been reallocated. Because
857 * it is pinned, we know that the log has not been pushed to disk and
858 * hence it will still be locked. Rather than sleeping until someone
859 * else pushes the log, push it ourselves before trying to get the lock.
865 trace_xfs_buf_lock(bp, _RET_IP_);
867 if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))
868 xfs_log_force(bp->b_mount, 0);
869 if (atomic_read(&bp->b_io_remaining))
870 blk_run_address_space(bp->b_target->bt_mapping);
874 trace_xfs_buf_lock_done(bp, _RET_IP_);
878 * Releases the lock on the buffer object.
879 * If the buffer is marked delwri but is not queued, do so before we
880 * unlock the buffer as we need to set flags correctly. We also need to
881 * take a reference for the delwri queue because the unlocker is going to
882 * drop their's and they don't know we just queued it.
888 if ((bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)) == XBF_DELWRI) {
889 atomic_inc(&bp->b_hold);
890 bp->b_flags |= XBF_ASYNC;
891 xfs_buf_delwri_queue(bp, 0);
897 trace_xfs_buf_unlock(bp, _RET_IP_);
902 * Pinning Buffer Storage in Memory
903 * Ensure that no attempt to force a buffer to disk will succeed.
909 trace_xfs_buf_pin(bp, _RET_IP_);
910 atomic_inc(&bp->b_pin_count);
917 trace_xfs_buf_unpin(bp, _RET_IP_);
919 if (atomic_dec_and_test(&bp->b_pin_count))
920 wake_up_all(&bp->b_waiters);
927 return atomic_read(&bp->b_pin_count);
934 DECLARE_WAITQUEUE (wait, current);
936 if (atomic_read(&bp->b_pin_count) == 0)
939 add_wait_queue(&bp->b_waiters, &wait);
941 set_current_state(TASK_UNINTERRUPTIBLE);
942 if (atomic_read(&bp->b_pin_count) == 0)
944 if (atomic_read(&bp->b_io_remaining))
945 blk_run_address_space(bp->b_target->bt_mapping);
948 remove_wait_queue(&bp->b_waiters, &wait);
949 set_current_state(TASK_RUNNING);
953 * Buffer Utility Routines
958 struct work_struct *work)
961 container_of(work, xfs_buf_t, b_iodone_work);
964 * We can get an EOPNOTSUPP to ordered writes. Here we clear the
965 * ordered flag and reissue them. Because we can't tell the higher
966 * layers directly that they should not issue ordered I/O anymore, they
967 * need to check if the _XFS_BARRIER_FAILED flag was set during I/O completion.
969 if ((bp->b_error == EOPNOTSUPP) &&
970 (bp->b_flags & (XBF_ORDERED|XBF_ASYNC)) == (XBF_ORDERED|XBF_ASYNC)) {
971 trace_xfs_buf_ordered_retry(bp, _RET_IP_);
972 bp->b_flags &= ~XBF_ORDERED;
973 bp->b_flags |= _XFS_BARRIER_FAILED;
974 xfs_buf_iorequest(bp);
975 } else if (bp->b_iodone)
976 (*(bp->b_iodone))(bp);
977 else if (bp->b_flags & XBF_ASYNC)
986 trace_xfs_buf_iodone(bp, _RET_IP_);
988 bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_READ_AHEAD);
989 if (bp->b_error == 0)
990 bp->b_flags |= XBF_DONE;
992 if ((bp->b_iodone) || (bp->b_flags & XBF_ASYNC)) {
994 INIT_WORK(&bp->b_iodone_work, xfs_buf_iodone_work);
995 queue_work(xfslogd_workqueue, &bp->b_iodone_work);
997 xfs_buf_iodone_work(&bp->b_iodone_work);
1000 complete(&bp->b_iowait);
1009 ASSERT(error >= 0 && error <= 0xffff);
1010 bp->b_error = (unsigned short)error;
1011 trace_xfs_buf_ioerror(bp, error, _RET_IP_);
1016 struct xfs_mount *mp,
1021 bp->b_strat = xfs_bdstrat_cb;
1023 bp->b_flags |= XBF_WRITE;
1024 bp->b_flags &= ~(XBF_ASYNC | XBF_READ);
1026 xfs_buf_delwri_dequeue(bp);
1027 xfs_buf_iostrategy(bp);
1029 error = xfs_buf_iowait(bp);
1031 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1041 trace_xfs_buf_bdwrite(bp, _RET_IP_);
1043 bp->b_strat = xfs_bdstrat_cb;
1046 bp->b_flags &= ~XBF_READ;
1047 bp->b_flags |= (XBF_DELWRI | XBF_ASYNC);
1049 xfs_buf_delwri_queue(bp, 1);
1053 * Called when we want to stop a buffer from getting written or read.
1054 * We attach the EIO error, muck with its flags, and call biodone
1055 * so that the proper iodone callbacks get called.
1061 #ifdef XFSERRORDEBUG
1062 ASSERT(XFS_BUF_ISREAD(bp) || bp->b_iodone);
1066 * No need to wait until the buffer is unpinned, we aren't flushing it.
1068 XFS_BUF_ERROR(bp, EIO);
1071 * We're calling biodone, so delete XBF_DONE flag.
1074 XFS_BUF_UNDELAYWRITE(bp);
1078 XFS_BUF_CLR_BDSTRAT_FUNC(bp);
1085 * Same as xfs_bioerror, except that we are releasing the buffer
1086 * here ourselves, and avoiding the biodone call.
1087 * This is meant for userdata errors; metadata bufs come with
1088 * iodone functions attached, so that we can track down errors.
1094 int64_t fl = XFS_BUF_BFLAGS(bp);
1096 * No need to wait until the buffer is unpinned.
1097 * We aren't flushing it.
1099 * chunkhold expects B_DONE to be set, whether
1100 * we actually finish the I/O or not. We don't want to
1101 * change that interface.
1104 XFS_BUF_UNDELAYWRITE(bp);
1107 XFS_BUF_CLR_IODONE_FUNC(bp);
1108 XFS_BUF_CLR_BDSTRAT_FUNC(bp);
1109 if (!(fl & XBF_ASYNC)) {
1111 * Mark b_error and B_ERROR _both_.
1112 * Lot's of chunkcache code assumes that.
1113 * There's no reason to mark error for
1116 XFS_BUF_ERROR(bp, EIO);
1117 XFS_BUF_FINISH_IOWAIT(bp);
1127 * All xfs metadata buffers except log state machine buffers
1128 * get this attached as their b_bdstrat callback function.
1129 * This is so that we can catch a buffer
1130 * after prematurely unpinning it to forcibly shutdown the filesystem.
1136 if (XFS_FORCED_SHUTDOWN(bp->b_mount)) {
1137 trace_xfs_bdstrat_shut(bp, _RET_IP_);
1139 * Metadata write that didn't get logged but
1140 * written delayed anyway. These aren't associated
1141 * with a transaction, and can be ignored.
1143 if (!bp->b_iodone && !XFS_BUF_ISREAD(bp))
1144 return xfs_bioerror_relse(bp);
1146 return xfs_bioerror(bp);
1149 xfs_buf_iorequest(bp);
1154 * Wrapper around bdstrat so that we can stop data from going to disk in case
1155 * we are shutting down the filesystem. Typically user data goes thru this
1156 * path; one of the exceptions is the superblock.
1160 struct xfs_mount *mp,
1163 if (XFS_FORCED_SHUTDOWN(mp)) {
1164 trace_xfs_bdstrat_shut(bp, _RET_IP_);
1165 xfs_bioerror_relse(bp);
1169 xfs_buf_iorequest(bp);
1177 if (atomic_dec_and_test(&bp->b_io_remaining) == 1) {
1178 bp->b_flags &= ~_XBF_PAGE_LOCKED;
1179 xfs_buf_ioend(bp, schedule);
1188 xfs_buf_t *bp = (xfs_buf_t *)bio->bi_private;
1189 unsigned int blocksize = bp->b_target->bt_bsize;
1190 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
1192 xfs_buf_ioerror(bp, -error);
1194 if (!error && xfs_buf_is_vmapped(bp) && (bp->b_flags & XBF_READ))
1195 invalidate_kernel_vmap_range(bp->b_addr, xfs_buf_vmap_len(bp));
1198 struct page *page = bvec->bv_page;
1200 ASSERT(!PagePrivate(page));
1201 if (unlikely(bp->b_error)) {
1202 if (bp->b_flags & XBF_READ)
1203 ClearPageUptodate(page);
1204 } else if (blocksize >= PAGE_CACHE_SIZE) {
1205 SetPageUptodate(page);
1206 } else if (!PagePrivate(page) &&
1207 (bp->b_flags & _XBF_PAGE_CACHE)) {
1208 set_page_region(page, bvec->bv_offset, bvec->bv_len);
1211 if (--bvec >= bio->bi_io_vec)
1212 prefetchw(&bvec->bv_page->flags);
1214 if (bp->b_flags & _XBF_PAGE_LOCKED)
1216 } while (bvec >= bio->bi_io_vec);
1218 _xfs_buf_ioend(bp, 1);
1226 int rw, map_i, total_nr_pages, nr_pages;
1228 int offset = bp->b_offset;
1229 int size = bp->b_count_desired;
1230 sector_t sector = bp->b_bn;
1231 unsigned int blocksize = bp->b_target->bt_bsize;
1233 total_nr_pages = bp->b_page_count;
1236 if (bp->b_flags & XBF_ORDERED) {
1237 ASSERT(!(bp->b_flags & XBF_READ));
1239 } else if (bp->b_flags & XBF_LOG_BUFFER) {
1240 ASSERT(!(bp->b_flags & XBF_READ_AHEAD));
1241 bp->b_flags &= ~_XBF_RUN_QUEUES;
1242 rw = (bp->b_flags & XBF_WRITE) ? WRITE_SYNC : READ_SYNC;
1243 } else if (bp->b_flags & _XBF_RUN_QUEUES) {
1244 ASSERT(!(bp->b_flags & XBF_READ_AHEAD));
1245 bp->b_flags &= ~_XBF_RUN_QUEUES;
1246 rw = (bp->b_flags & XBF_WRITE) ? WRITE_META : READ_META;
1248 rw = (bp->b_flags & XBF_WRITE) ? WRITE :
1249 (bp->b_flags & XBF_READ_AHEAD) ? READA : READ;
1252 /* Special code path for reading a sub page size buffer in --
1253 * we populate up the whole page, and hence the other metadata
1254 * in the same page. This optimization is only valid when the
1255 * filesystem block size is not smaller than the page size.
1257 if ((bp->b_buffer_length < PAGE_CACHE_SIZE) &&
1258 ((bp->b_flags & (XBF_READ|_XBF_PAGE_LOCKED)) ==
1259 (XBF_READ|_XBF_PAGE_LOCKED)) &&
1260 (blocksize >= PAGE_CACHE_SIZE)) {
1261 bio = bio_alloc(GFP_NOIO, 1);
1263 bio->bi_bdev = bp->b_target->bt_bdev;
1264 bio->bi_sector = sector - (offset >> BBSHIFT);
1265 bio->bi_end_io = xfs_buf_bio_end_io;
1266 bio->bi_private = bp;
1268 bio_add_page(bio, bp->b_pages[0], PAGE_CACHE_SIZE, 0);
1271 atomic_inc(&bp->b_io_remaining);
1277 atomic_inc(&bp->b_io_remaining);
1278 nr_pages = BIO_MAX_SECTORS >> (PAGE_SHIFT - BBSHIFT);
1279 if (nr_pages > total_nr_pages)
1280 nr_pages = total_nr_pages;
1282 bio = bio_alloc(GFP_NOIO, nr_pages);
1283 bio->bi_bdev = bp->b_target->bt_bdev;
1284 bio->bi_sector = sector;
1285 bio->bi_end_io = xfs_buf_bio_end_io;
1286 bio->bi_private = bp;
1288 for (; size && nr_pages; nr_pages--, map_i++) {
1289 int rbytes, nbytes = PAGE_CACHE_SIZE - offset;
1294 rbytes = bio_add_page(bio, bp->b_pages[map_i], nbytes, offset);
1295 if (rbytes < nbytes)
1299 sector += nbytes >> BBSHIFT;
1305 if (likely(bio->bi_size)) {
1306 if (xfs_buf_is_vmapped(bp)) {
1307 flush_kernel_vmap_range(bp->b_addr,
1308 xfs_buf_vmap_len(bp));
1310 submit_bio(rw, bio);
1315 xfs_buf_ioerror(bp, EIO);
1323 trace_xfs_buf_iorequest(bp, _RET_IP_);
1325 if (bp->b_flags & XBF_DELWRI) {
1326 xfs_buf_delwri_queue(bp, 1);
1330 if (bp->b_flags & XBF_WRITE) {
1331 xfs_buf_wait_unpin(bp);
1336 /* Set the count to 1 initially, this will stop an I/O
1337 * completion callout which happens before we have started
1338 * all the I/O from calling xfs_buf_ioend too early.
1340 atomic_set(&bp->b_io_remaining, 1);
1341 _xfs_buf_ioapply(bp);
1342 _xfs_buf_ioend(bp, 0);
1349 * Waits for I/O to complete on the buffer supplied.
1350 * It returns immediately if no I/O is pending.
1351 * It returns the I/O error code, if any, or 0 if there was no error.
1357 trace_xfs_buf_iowait(bp, _RET_IP_);
1359 if (atomic_read(&bp->b_io_remaining))
1360 blk_run_address_space(bp->b_target->bt_mapping);
1361 wait_for_completion(&bp->b_iowait);
1363 trace_xfs_buf_iowait_done(bp, _RET_IP_);
1374 if (bp->b_flags & XBF_MAPPED)
1375 return XFS_BUF_PTR(bp) + offset;
1377 offset += bp->b_offset;
1378 page = bp->b_pages[offset >> PAGE_CACHE_SHIFT];
1379 return (xfs_caddr_t)page_address(page) + (offset & (PAGE_CACHE_SIZE-1));
1383 * Move data into or out of a buffer.
1387 xfs_buf_t *bp, /* buffer to process */
1388 size_t boff, /* starting buffer offset */
1389 size_t bsize, /* length to copy */
1390 void *data, /* data address */
1391 xfs_buf_rw_t mode) /* read/write/zero flag */
1393 size_t bend, cpoff, csize;
1396 bend = boff + bsize;
1397 while (boff < bend) {
1398 page = bp->b_pages[xfs_buf_btoct(boff + bp->b_offset)];
1399 cpoff = xfs_buf_poff(boff + bp->b_offset);
1400 csize = min_t(size_t,
1401 PAGE_CACHE_SIZE-cpoff, bp->b_count_desired-boff);
1403 ASSERT(((csize + cpoff) <= PAGE_CACHE_SIZE));
1407 memset(page_address(page) + cpoff, 0, csize);
1410 memcpy(data, page_address(page) + cpoff, csize);
1413 memcpy(page_address(page) + cpoff, data, csize);
1422 * Handling of buffer targets (buftargs).
1426 * Wait for any bufs with callbacks that have been submitted but
1427 * have not yet returned... walk the hash list for the target.
1434 xfs_bufhash_t *hash;
1437 for (i = 0; i < (1 << btp->bt_hashshift); i++) {
1438 hash = &btp->bt_hash[i];
1440 spin_lock(&hash->bh_lock);
1441 list_for_each_entry_safe(bp, n, &hash->bh_list, b_hash_list) {
1442 ASSERT(btp == bp->b_target);
1443 if (!(bp->b_flags & XBF_FS_MANAGED)) {
1444 spin_unlock(&hash->bh_lock);
1446 * Catch superblock reference count leaks
1449 BUG_ON(bp->b_bn == 0);
1454 spin_unlock(&hash->bh_lock);
1459 * Allocate buffer hash table for a given target.
1460 * For devices containing metadata (i.e. not the log/realtime devices)
1461 * we need to allocate a much larger hash table.
1470 btp->bt_hashshift = external ? 3 : 8; /* 8 or 256 buckets */
1471 btp->bt_hashmask = (1 << btp->bt_hashshift) - 1;
1472 btp->bt_hash = kmem_zalloc_large((1 << btp->bt_hashshift) *
1473 sizeof(xfs_bufhash_t));
1474 for (i = 0; i < (1 << btp->bt_hashshift); i++) {
1475 spin_lock_init(&btp->bt_hash[i].bh_lock);
1476 INIT_LIST_HEAD(&btp->bt_hash[i].bh_list);
1484 kmem_free_large(btp->bt_hash);
1485 btp->bt_hash = NULL;
1489 * buftarg list for delwrite queue processing
1491 static LIST_HEAD(xfs_buftarg_list);
1492 static DEFINE_SPINLOCK(xfs_buftarg_lock);
1495 xfs_register_buftarg(
1498 spin_lock(&xfs_buftarg_lock);
1499 list_add(&btp->bt_list, &xfs_buftarg_list);
1500 spin_unlock(&xfs_buftarg_lock);
1504 xfs_unregister_buftarg(
1507 spin_lock(&xfs_buftarg_lock);
1508 list_del(&btp->bt_list);
1509 spin_unlock(&xfs_buftarg_lock);
1514 struct xfs_mount *mp,
1515 struct xfs_buftarg *btp)
1517 xfs_flush_buftarg(btp, 1);
1518 if (mp->m_flags & XFS_MOUNT_BARRIER)
1519 xfs_blkdev_issue_flush(btp);
1520 xfs_free_bufhash(btp);
1521 iput(btp->bt_mapping->host);
1523 /* Unregister the buftarg first so that we don't get a
1524 * wakeup finding a non-existent task
1526 xfs_unregister_buftarg(btp);
1527 kthread_stop(btp->bt_task);
1533 xfs_setsize_buftarg_flags(
1535 unsigned int blocksize,
1536 unsigned int sectorsize,
1539 btp->bt_bsize = blocksize;
1540 btp->bt_sshift = ffs(sectorsize) - 1;
1541 btp->bt_smask = sectorsize - 1;
1543 if (set_blocksize(btp->bt_bdev, sectorsize)) {
1545 "XFS: Cannot set_blocksize to %u on device %s\n",
1546 sectorsize, XFS_BUFTARG_NAME(btp));
1551 (PAGE_CACHE_SIZE / BITS_PER_LONG) > sectorsize) {
1553 "XFS: %u byte sectors in use on device %s. "
1554 "This is suboptimal; %u or greater is ideal.\n",
1555 sectorsize, XFS_BUFTARG_NAME(btp),
1556 (unsigned int)PAGE_CACHE_SIZE / BITS_PER_LONG);
1563 * When allocating the initial buffer target we have not yet
1564 * read in the superblock, so don't know what sized sectors
1565 * are being used is at this early stage. Play safe.
1568 xfs_setsize_buftarg_early(
1570 struct block_device *bdev)
1572 return xfs_setsize_buftarg_flags(btp,
1573 PAGE_CACHE_SIZE, bdev_logical_block_size(bdev), 0);
1577 xfs_setsize_buftarg(
1579 unsigned int blocksize,
1580 unsigned int sectorsize)
1582 return xfs_setsize_buftarg_flags(btp, blocksize, sectorsize, 1);
1586 xfs_mapping_buftarg(
1588 struct block_device *bdev)
1590 struct backing_dev_info *bdi;
1591 struct inode *inode;
1592 struct address_space *mapping;
1593 static const struct address_space_operations mapping_aops = {
1594 .sync_page = block_sync_page,
1595 .migratepage = fail_migrate_page,
1598 inode = new_inode(bdev->bd_inode->i_sb);
1601 "XFS: Cannot allocate mapping inode for device %s\n",
1602 XFS_BUFTARG_NAME(btp));
1605 inode->i_mode = S_IFBLK;
1606 inode->i_bdev = bdev;
1607 inode->i_rdev = bdev->bd_dev;
1608 bdi = blk_get_backing_dev_info(bdev);
1610 bdi = &default_backing_dev_info;
1611 mapping = &inode->i_data;
1612 mapping->a_ops = &mapping_aops;
1613 mapping->backing_dev_info = bdi;
1614 mapping_set_gfp_mask(mapping, GFP_NOFS);
1615 btp->bt_mapping = mapping;
1620 xfs_alloc_delwrite_queue(
1626 INIT_LIST_HEAD(&btp->bt_list);
1627 INIT_LIST_HEAD(&btp->bt_delwrite_queue);
1628 spin_lock_init(&btp->bt_delwrite_lock);
1630 btp->bt_task = kthread_run(xfsbufd, btp, "xfsbufd/%s", fsname);
1631 if (IS_ERR(btp->bt_task)) {
1632 error = PTR_ERR(btp->bt_task);
1635 xfs_register_buftarg(btp);
1642 struct block_device *bdev,
1648 btp = kmem_zalloc(sizeof(*btp), KM_SLEEP);
1650 btp->bt_dev = bdev->bd_dev;
1651 btp->bt_bdev = bdev;
1652 if (xfs_setsize_buftarg_early(btp, bdev))
1654 if (xfs_mapping_buftarg(btp, bdev))
1656 if (xfs_alloc_delwrite_queue(btp, fsname))
1658 xfs_alloc_bufhash(btp, external);
1668 * Delayed write buffer handling
1671 xfs_buf_delwri_queue(
1675 struct list_head *dwq = &bp->b_target->bt_delwrite_queue;
1676 spinlock_t *dwlk = &bp->b_target->bt_delwrite_lock;
1678 trace_xfs_buf_delwri_queue(bp, _RET_IP_);
1680 ASSERT((bp->b_flags&(XBF_DELWRI|XBF_ASYNC)) == (XBF_DELWRI|XBF_ASYNC));
1683 /* If already in the queue, dequeue and place at tail */
1684 if (!list_empty(&bp->b_list)) {
1685 ASSERT(bp->b_flags & _XBF_DELWRI_Q);
1687 atomic_dec(&bp->b_hold);
1688 list_del(&bp->b_list);
1691 if (list_empty(dwq)) {
1692 /* start xfsbufd as it is about to have something to do */
1693 wake_up_process(bp->b_target->bt_task);
1696 bp->b_flags |= _XBF_DELWRI_Q;
1697 list_add_tail(&bp->b_list, dwq);
1698 bp->b_queuetime = jiffies;
1706 xfs_buf_delwri_dequeue(
1709 spinlock_t *dwlk = &bp->b_target->bt_delwrite_lock;
1713 if ((bp->b_flags & XBF_DELWRI) && !list_empty(&bp->b_list)) {
1714 ASSERT(bp->b_flags & _XBF_DELWRI_Q);
1715 list_del_init(&bp->b_list);
1718 bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q);
1724 trace_xfs_buf_delwri_dequeue(bp, _RET_IP_);
1728 * If a delwri buffer needs to be pushed before it has aged out, then promote
1729 * it to the head of the delwri queue so that it will be flushed on the next
1730 * xfsbufd run. We do this by resetting the queuetime of the buffer to be older
1731 * than the age currently needed to flush the buffer. Hence the next time the
1732 * xfsbufd sees it is guaranteed to be considered old enough to flush.
1735 xfs_buf_delwri_promote(
1738 struct xfs_buftarg *btp = bp->b_target;
1739 long age = xfs_buf_age_centisecs * msecs_to_jiffies(10) + 1;
1741 ASSERT(bp->b_flags & XBF_DELWRI);
1742 ASSERT(bp->b_flags & _XBF_DELWRI_Q);
1745 * Check the buffer age before locking the delayed write queue as we
1746 * don't need to promote buffers that are already past the flush age.
1748 if (bp->b_queuetime < jiffies - age)
1750 bp->b_queuetime = jiffies - age;
1751 spin_lock(&btp->bt_delwrite_lock);
1752 list_move(&bp->b_list, &btp->bt_delwrite_queue);
1753 spin_unlock(&btp->bt_delwrite_lock);
1757 xfs_buf_runall_queues(
1758 struct workqueue_struct *queue)
1760 flush_workqueue(queue);
1765 struct shrinker *shrink,
1771 spin_lock(&xfs_buftarg_lock);
1772 list_for_each_entry(btp, &xfs_buftarg_list, bt_list) {
1773 if (test_bit(XBT_FORCE_SLEEP, &btp->bt_flags))
1775 if (list_empty(&btp->bt_delwrite_queue))
1777 set_bit(XBT_FORCE_FLUSH, &btp->bt_flags);
1778 wake_up_process(btp->bt_task);
1780 spin_unlock(&xfs_buftarg_lock);
1785 * Move as many buffers as specified to the supplied list
1786 * idicating if we skipped any buffers to prevent deadlocks.
1789 xfs_buf_delwri_split(
1790 xfs_buftarg_t *target,
1791 struct list_head *list,
1795 struct list_head *dwq = &target->bt_delwrite_queue;
1796 spinlock_t *dwlk = &target->bt_delwrite_lock;
1800 force = test_and_clear_bit(XBT_FORCE_FLUSH, &target->bt_flags);
1801 INIT_LIST_HEAD(list);
1803 list_for_each_entry_safe(bp, n, dwq, b_list) {
1804 trace_xfs_buf_delwri_split(bp, _RET_IP_);
1805 ASSERT(bp->b_flags & XBF_DELWRI);
1807 if (!xfs_buf_ispin(bp) && !xfs_buf_cond_lock(bp)) {
1809 time_before(jiffies, bp->b_queuetime + age)) {
1814 bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q|
1816 bp->b_flags |= XBF_WRITE;
1817 list_move_tail(&bp->b_list, list);
1828 * Compare function is more complex than it needs to be because
1829 * the return value is only 32 bits and we are doing comparisons
1835 struct list_head *a,
1836 struct list_head *b)
1838 struct xfs_buf *ap = container_of(a, struct xfs_buf, b_list);
1839 struct xfs_buf *bp = container_of(b, struct xfs_buf, b_list);
1842 diff = ap->b_bn - bp->b_bn;
1851 xfs_buf_delwri_sort(
1852 xfs_buftarg_t *target,
1853 struct list_head *list)
1855 list_sort(NULL, list, xfs_buf_cmp);
1862 xfs_buftarg_t *target = (xfs_buftarg_t *)data;
1864 current->flags |= PF_MEMALLOC;
1869 long age = xfs_buf_age_centisecs * msecs_to_jiffies(10);
1870 long tout = xfs_buf_timer_centisecs * msecs_to_jiffies(10);
1872 struct list_head tmp;
1874 if (unlikely(freezing(current))) {
1875 set_bit(XBT_FORCE_SLEEP, &target->bt_flags);
1878 clear_bit(XBT_FORCE_SLEEP, &target->bt_flags);
1881 /* sleep for a long time if there is nothing to do. */
1882 if (list_empty(&target->bt_delwrite_queue))
1883 tout = MAX_SCHEDULE_TIMEOUT;
1884 schedule_timeout_interruptible(tout);
1886 xfs_buf_delwri_split(target, &tmp, age);
1887 list_sort(NULL, &tmp, xfs_buf_cmp);
1888 while (!list_empty(&tmp)) {
1890 bp = list_first_entry(&tmp, struct xfs_buf, b_list);
1891 list_del_init(&bp->b_list);
1892 xfs_buf_iostrategy(bp);
1896 blk_run_address_space(target->bt_mapping);
1898 } while (!kthread_should_stop());
1904 * Go through all incore buffers, and release buffers if they belong to
1905 * the given device. This is used in filesystem error handling to
1906 * preserve the consistency of its metadata.
1910 xfs_buftarg_t *target,
1915 LIST_HEAD(tmp_list);
1916 LIST_HEAD(wait_list);
1918 xfs_buf_runall_queues(xfsconvertd_workqueue);
1919 xfs_buf_runall_queues(xfsdatad_workqueue);
1920 xfs_buf_runall_queues(xfslogd_workqueue);
1922 set_bit(XBT_FORCE_FLUSH, &target->bt_flags);
1923 pincount = xfs_buf_delwri_split(target, &tmp_list, 0);
1926 * Dropped the delayed write list lock, now walk the temporary list.
1927 * All I/O is issued async and then if we need to wait for completion
1928 * we do that after issuing all the IO.
1930 list_sort(NULL, &tmp_list, xfs_buf_cmp);
1931 while (!list_empty(&tmp_list)) {
1932 bp = list_first_entry(&tmp_list, struct xfs_buf, b_list);
1933 ASSERT(target == bp->b_target);
1934 list_del_init(&bp->b_list);
1936 bp->b_flags &= ~XBF_ASYNC;
1937 list_add(&bp->b_list, &wait_list);
1939 xfs_buf_iostrategy(bp);
1943 /* Expedite and wait for IO to complete. */
1944 blk_run_address_space(target->bt_mapping);
1945 while (!list_empty(&wait_list)) {
1946 bp = list_first_entry(&wait_list, struct xfs_buf, b_list);
1948 list_del_init(&bp->b_list);
1960 xfs_buf_zone = kmem_zone_init_flags(sizeof(xfs_buf_t), "xfs_buf",
1961 KM_ZONE_HWALIGN, NULL);
1965 xfslogd_workqueue = create_workqueue("xfslogd");
1966 if (!xfslogd_workqueue)
1967 goto out_free_buf_zone;
1969 xfsdatad_workqueue = create_workqueue("xfsdatad");
1970 if (!xfsdatad_workqueue)
1971 goto out_destroy_xfslogd_workqueue;
1973 xfsconvertd_workqueue = create_workqueue("xfsconvertd");
1974 if (!xfsconvertd_workqueue)
1975 goto out_destroy_xfsdatad_workqueue;
1977 register_shrinker(&xfs_buf_shake);
1980 out_destroy_xfsdatad_workqueue:
1981 destroy_workqueue(xfsdatad_workqueue);
1982 out_destroy_xfslogd_workqueue:
1983 destroy_workqueue(xfslogd_workqueue);
1985 kmem_zone_destroy(xfs_buf_zone);
1991 xfs_buf_terminate(void)
1993 unregister_shrinker(&xfs_buf_shake);
1994 destroy_workqueue(xfsconvertd_workqueue);
1995 destroy_workqueue(xfsdatad_workqueue);
1996 destroy_workqueue(xfslogd_workqueue);
1997 kmem_zone_destroy(xfs_buf_zone);
2000 #ifdef CONFIG_KDB_MODULES
2002 xfs_get_buftarg_list(void)
2004 return &xfs_buftarg_list;