1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_mount.h"
13 #include "xfs_inode.h"
14 #include "xfs_trans.h"
15 #include "xfs_trans_priv.h"
16 #include "xfs_inode_item.h"
17 #include "xfs_quota.h"
18 #include "xfs_trace.h"
19 #include "xfs_icache.h"
20 #include "xfs_bmap_util.h"
21 #include "xfs_dquot_item.h"
22 #include "xfs_dquot.h"
23 #include "xfs_reflink.h"
24 #include "xfs_ialloc.h"
27 #include <linux/iversion.h>
29 /* Radix tree tags for incore inode tree. */
31 /* inode is to be reclaimed */
32 #define XFS_ICI_RECLAIM_TAG 0
33 /* Inode has speculative preallocations (posteof or cow) to clean. */
34 #define XFS_ICI_BLOCKGC_TAG 1
37 * The goal for walking incore inodes. These can correspond with incore inode
38 * radix tree tags when convenient. Avoid existing XFS_IWALK namespace.
40 enum xfs_icwalk_goal {
41 /* Goals directly associated with tagged inodes. */
42 XFS_ICWALK_BLOCKGC = XFS_ICI_BLOCKGC_TAG,
43 XFS_ICWALK_RECLAIM = XFS_ICI_RECLAIM_TAG,
46 static int xfs_icwalk(struct xfs_mount *mp,
47 enum xfs_icwalk_goal goal, struct xfs_icwalk *icw);
48 static int xfs_icwalk_ag(struct xfs_perag *pag,
49 enum xfs_icwalk_goal goal, struct xfs_icwalk *icw);
52 * Private inode cache walk flags for struct xfs_icwalk. Must not
53 * coincide with XFS_ICWALK_FLAGS_VALID.
56 /* Stop scanning after icw_scan_limit inodes. */
57 #define XFS_ICWALK_FLAG_SCAN_LIMIT (1U << 28)
59 #define XFS_ICWALK_FLAG_RECLAIM_SICK (1U << 27)
60 #define XFS_ICWALK_FLAG_UNION (1U << 26) /* union filter algorithm */
62 #define XFS_ICWALK_PRIVATE_FLAGS (XFS_ICWALK_FLAG_SCAN_LIMIT | \
63 XFS_ICWALK_FLAG_RECLAIM_SICK | \
64 XFS_ICWALK_FLAG_UNION)
67 * Allocate and initialise an xfs_inode.
77 * XXX: If this didn't occur in transactions, we could drop GFP_NOFAIL
78 * and return NULL here on ENOMEM.
80 ip = kmem_cache_alloc(xfs_inode_zone, GFP_KERNEL | __GFP_NOFAIL);
82 if (inode_init_always(mp->m_super, VFS_I(ip))) {
83 kmem_cache_free(xfs_inode_zone, ip);
87 /* VFS doesn't initialise i_mode or i_state! */
88 VFS_I(ip)->i_mode = 0;
89 VFS_I(ip)->i_state = 0;
91 XFS_STATS_INC(mp, vn_active);
92 ASSERT(atomic_read(&ip->i_pincount) == 0);
93 ASSERT(ip->i_ino == 0);
95 /* initialise the xfs inode */
98 memset(&ip->i_imap, 0, sizeof(struct xfs_imap));
101 memset(&ip->i_df, 0, sizeof(ip->i_df));
103 ip->i_delayed_blks = 0;
104 ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
109 INIT_WORK(&ip->i_ioend_work, xfs_end_io);
110 INIT_LIST_HEAD(&ip->i_ioend_list);
111 spin_lock_init(&ip->i_ioend_lock);
117 xfs_inode_free_callback(
118 struct rcu_head *head)
120 struct inode *inode = container_of(head, struct inode, i_rcu);
121 struct xfs_inode *ip = XFS_I(inode);
123 switch (VFS_I(ip)->i_mode & S_IFMT) {
127 xfs_idestroy_fork(&ip->i_df);
132 xfs_idestroy_fork(ip->i_afp);
133 kmem_cache_free(xfs_ifork_zone, ip->i_afp);
136 xfs_idestroy_fork(ip->i_cowfp);
137 kmem_cache_free(xfs_ifork_zone, ip->i_cowfp);
140 ASSERT(!test_bit(XFS_LI_IN_AIL,
141 &ip->i_itemp->ili_item.li_flags));
142 xfs_inode_item_destroy(ip);
146 kmem_cache_free(xfs_inode_zone, ip);
151 struct xfs_inode *ip)
153 /* asserts to verify all state is correct here */
154 ASSERT(atomic_read(&ip->i_pincount) == 0);
155 ASSERT(!ip->i_itemp || list_empty(&ip->i_itemp->ili_item.li_bio_list));
156 XFS_STATS_DEC(ip->i_mount, vn_active);
158 call_rcu(&VFS_I(ip)->i_rcu, xfs_inode_free_callback);
163 struct xfs_inode *ip)
165 ASSERT(!xfs_iflags_test(ip, XFS_IFLUSHING));
168 * Because we use RCU freeing we need to ensure the inode always
169 * appears to be reclaimed with an invalid inode number when in the
170 * free state. The ip->i_flags_lock provides the barrier against lookup
173 spin_lock(&ip->i_flags_lock);
174 ip->i_flags = XFS_IRECLAIM;
176 spin_unlock(&ip->i_flags_lock);
178 __xfs_inode_free(ip);
182 * Queue background inode reclaim work if there are reclaimable inodes and there
183 * isn't reclaim work already scheduled or in progress.
186 xfs_reclaim_work_queue(
187 struct xfs_mount *mp)
191 if (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_RECLAIM_TAG)) {
192 queue_delayed_work(mp->m_reclaim_workqueue, &mp->m_reclaim_work,
193 msecs_to_jiffies(xfs_syncd_centisecs / 6 * 10));
199 * Background scanning to trim preallocated space. This is queued based on the
200 * 'speculative_prealloc_lifetime' tunable (5m by default).
204 struct xfs_perag *pag)
206 struct xfs_mount *mp = pag->pag_mount;
208 if (!xfs_is_blockgc_enabled(mp))
212 if (radix_tree_tagged(&pag->pag_ici_root, XFS_ICI_BLOCKGC_TAG))
213 queue_delayed_work(pag->pag_mount->m_blockgc_wq,
214 &pag->pag_blockgc_work,
215 msecs_to_jiffies(xfs_blockgc_secs * 1000));
219 /* Set a tag on both the AG incore inode tree and the AG radix tree. */
221 xfs_perag_set_inode_tag(
222 struct xfs_perag *pag,
226 struct xfs_mount *mp = pag->pag_mount;
229 lockdep_assert_held(&pag->pag_ici_lock);
231 was_tagged = radix_tree_tagged(&pag->pag_ici_root, tag);
232 radix_tree_tag_set(&pag->pag_ici_root, agino, tag);
234 if (tag == XFS_ICI_RECLAIM_TAG)
235 pag->pag_ici_reclaimable++;
240 /* propagate the tag up into the perag radix tree */
241 spin_lock(&mp->m_perag_lock);
242 radix_tree_tag_set(&mp->m_perag_tree, pag->pag_agno, tag);
243 spin_unlock(&mp->m_perag_lock);
245 /* start background work */
247 case XFS_ICI_RECLAIM_TAG:
248 xfs_reclaim_work_queue(mp);
250 case XFS_ICI_BLOCKGC_TAG:
251 xfs_blockgc_queue(pag);
255 trace_xfs_perag_set_inode_tag(mp, pag->pag_agno, tag, _RET_IP_);
258 /* Clear a tag on both the AG incore inode tree and the AG radix tree. */
260 xfs_perag_clear_inode_tag(
261 struct xfs_perag *pag,
265 struct xfs_mount *mp = pag->pag_mount;
267 lockdep_assert_held(&pag->pag_ici_lock);
270 * Reclaim can signal (with a null agino) that it cleared its own tag
271 * by removing the inode from the radix tree.
273 if (agino != NULLAGINO)
274 radix_tree_tag_clear(&pag->pag_ici_root, agino, tag);
276 ASSERT(tag == XFS_ICI_RECLAIM_TAG);
278 if (tag == XFS_ICI_RECLAIM_TAG)
279 pag->pag_ici_reclaimable--;
281 if (radix_tree_tagged(&pag->pag_ici_root, tag))
284 /* clear the tag from the perag radix tree */
285 spin_lock(&mp->m_perag_lock);
286 radix_tree_tag_clear(&mp->m_perag_tree, pag->pag_agno, tag);
287 spin_unlock(&mp->m_perag_lock);
289 trace_xfs_perag_clear_inode_tag(mp, pag->pag_agno, tag, _RET_IP_);
294 struct xfs_inode *ip)
296 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_INEW_BIT);
297 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_INEW_BIT);
300 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
301 if (!xfs_iflags_test(ip, XFS_INEW))
305 finish_wait(wq, &wait.wq_entry);
309 * When we recycle a reclaimable inode, we need to re-initialise the VFS inode
310 * part of the structure. This is made more complex by the fact we store
311 * information about the on-disk values in the VFS inode and so we can't just
312 * overwrite the values unconditionally. Hence we save the parameters we
313 * need to retain across reinitialisation, and rewrite them into the VFS inode
314 * after reinitialisation even if it fails.
318 struct xfs_mount *mp,
322 uint32_t nlink = inode->i_nlink;
323 uint32_t generation = inode->i_generation;
324 uint64_t version = inode_peek_iversion(inode);
325 umode_t mode = inode->i_mode;
326 dev_t dev = inode->i_rdev;
327 kuid_t uid = inode->i_uid;
328 kgid_t gid = inode->i_gid;
330 error = inode_init_always(mp->m_super, inode);
332 set_nlink(inode, nlink);
333 inode->i_generation = generation;
334 inode_set_iversion_queried(inode, version);
335 inode->i_mode = mode;
343 * Carefully nudge an inode whose VFS state has been torn down back into a
344 * usable state. Drops the i_flags_lock and the rcu read lock.
348 struct xfs_perag *pag,
349 struct xfs_inode *ip) __releases(&ip->i_flags_lock)
351 struct xfs_mount *mp = ip->i_mount;
352 struct inode *inode = VFS_I(ip);
355 trace_xfs_iget_recycle(ip);
358 * We need to make it look like the inode is being reclaimed to prevent
359 * the actual reclaim workers from stomping over us while we recycle
360 * the inode. We can't clear the radix tree tag yet as it requires
361 * pag_ici_lock to be held exclusive.
363 ip->i_flags |= XFS_IRECLAIM;
365 spin_unlock(&ip->i_flags_lock);
368 ASSERT(!rwsem_is_locked(&inode->i_rwsem));
369 error = xfs_reinit_inode(mp, inode);
374 * Re-initializing the inode failed, and we are in deep
375 * trouble. Try to re-add it to the reclaim list.
378 spin_lock(&ip->i_flags_lock);
379 wake = !!__xfs_iflags_test(ip, XFS_INEW);
380 ip->i_flags &= ~(XFS_INEW | XFS_IRECLAIM);
382 wake_up_bit(&ip->i_flags, __XFS_INEW_BIT);
383 ASSERT(ip->i_flags & XFS_IRECLAIMABLE);
384 spin_unlock(&ip->i_flags_lock);
387 trace_xfs_iget_recycle_fail(ip);
391 spin_lock(&pag->pag_ici_lock);
392 spin_lock(&ip->i_flags_lock);
395 * Clear the per-lifetime state in the inode as we are now effectively
396 * a new inode and need to return to the initial state before reuse
399 ip->i_flags &= ~XFS_IRECLAIM_RESET_FLAGS;
400 ip->i_flags |= XFS_INEW;
401 xfs_perag_clear_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
402 XFS_ICI_RECLAIM_TAG);
403 inode->i_state = I_NEW;
404 spin_unlock(&ip->i_flags_lock);
405 spin_unlock(&pag->pag_ici_lock);
411 * If we are allocating a new inode, then check what was returned is
412 * actually a free, empty inode. If we are not allocating an inode,
413 * then check we didn't find a free inode.
416 * 0 if the inode free state matches the lookup context
417 * -ENOENT if the inode is free and we are not allocating
418 * -EFSCORRUPTED if there is any state mismatch at all
421 xfs_iget_check_free_state(
422 struct xfs_inode *ip,
425 if (flags & XFS_IGET_CREATE) {
426 /* should be a free inode */
427 if (VFS_I(ip)->i_mode != 0) {
428 xfs_warn(ip->i_mount,
429 "Corruption detected! Free inode 0x%llx not marked free! (mode 0x%x)",
430 ip->i_ino, VFS_I(ip)->i_mode);
431 return -EFSCORRUPTED;
434 if (ip->i_nblocks != 0) {
435 xfs_warn(ip->i_mount,
436 "Corruption detected! Free inode 0x%llx has blocks allocated!",
438 return -EFSCORRUPTED;
443 /* should be an allocated inode */
444 if (VFS_I(ip)->i_mode == 0)
450 /* Make all pending inactivation work start immediately. */
452 xfs_inodegc_queue_all(
453 struct xfs_mount *mp)
455 struct xfs_inodegc *gc;
458 for_each_online_cpu(cpu) {
459 gc = per_cpu_ptr(mp->m_inodegc, cpu);
460 if (!llist_empty(&gc->list))
461 queue_work_on(cpu, mp->m_inodegc_wq, &gc->work);
466 * Check the validity of the inode we just found it the cache
470 struct xfs_perag *pag,
471 struct xfs_inode *ip,
474 int lock_flags) __releases(RCU)
476 struct inode *inode = VFS_I(ip);
477 struct xfs_mount *mp = ip->i_mount;
481 * check for re-use of an inode within an RCU grace period due to the
482 * radix tree nodes not being updated yet. We monitor for this by
483 * setting the inode number to zero before freeing the inode structure.
484 * If the inode has been reallocated and set up, then the inode number
485 * will not match, so check for that, too.
487 spin_lock(&ip->i_flags_lock);
488 if (ip->i_ino != ino)
492 * If we are racing with another cache hit that is currently
493 * instantiating this inode or currently recycling it out of
494 * reclaimable state, wait for the initialisation to complete
497 * If we're racing with the inactivation worker we also want to wait.
498 * If we're creating a new file, it's possible that the worker
499 * previously marked the inode as free on disk but hasn't finished
500 * updating the incore state yet. The AGI buffer will be dirty and
501 * locked to the icreate transaction, so a synchronous push of the
502 * inodegc workers would result in deadlock. For a regular iget, the
503 * worker is running already, so we might as well wait.
505 * XXX(hch): eventually we should do something equivalent to
506 * wait_on_inode to wait for these flags to be cleared
507 * instead of polling for it.
509 if (ip->i_flags & (XFS_INEW | XFS_IRECLAIM | XFS_INACTIVATING))
512 if (ip->i_flags & XFS_NEED_INACTIVE) {
513 /* Unlinked inodes cannot be re-grabbed. */
514 if (VFS_I(ip)->i_nlink == 0) {
518 goto out_inodegc_flush;
522 * Check the inode free state is valid. This also detects lookup
523 * racing with unlinks.
525 error = xfs_iget_check_free_state(ip, flags);
529 /* Skip inodes that have no vfs state. */
530 if ((flags & XFS_IGET_INCORE) &&
531 (ip->i_flags & XFS_IRECLAIMABLE))
534 /* The inode fits the selection criteria; process it. */
535 if (ip->i_flags & XFS_IRECLAIMABLE) {
536 /* Drops i_flags_lock and RCU read lock. */
537 error = xfs_iget_recycle(pag, ip);
541 /* If the VFS inode is being torn down, pause and try again. */
545 /* We've got a live one. */
546 spin_unlock(&ip->i_flags_lock);
548 trace_xfs_iget_hit(ip);
552 xfs_ilock(ip, lock_flags);
554 if (!(flags & XFS_IGET_INCORE))
555 xfs_iflags_clear(ip, XFS_ISTALE);
556 XFS_STATS_INC(mp, xs_ig_found);
561 trace_xfs_iget_skip(ip);
562 XFS_STATS_INC(mp, xs_ig_frecycle);
565 spin_unlock(&ip->i_flags_lock);
570 spin_unlock(&ip->i_flags_lock);
573 * Do not wait for the workers, because the caller could hold an AGI
574 * buffer lock. We're just going to sleep in a loop anyway.
576 if (xfs_is_inodegc_enabled(mp))
577 xfs_inodegc_queue_all(mp);
583 struct xfs_mount *mp,
584 struct xfs_perag *pag,
587 struct xfs_inode **ipp,
591 struct xfs_inode *ip;
593 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino);
596 ip = xfs_inode_alloc(mp, ino);
600 error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, flags);
605 * For version 5 superblocks, if we are initialising a new inode and we
606 * are not utilising the XFS_FEAT_IKEEP inode cluster mode, we can
607 * simply build the new inode core with a random generation number.
609 * For version 4 (and older) superblocks, log recovery is dependent on
610 * the i_flushiter field being initialised from the current on-disk
611 * value and hence we must also read the inode off disk even when
612 * initializing new inodes.
614 if (xfs_has_v3inodes(mp) &&
615 (flags & XFS_IGET_CREATE) && !xfs_has_ikeep(mp)) {
616 VFS_I(ip)->i_generation = prandom_u32();
620 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp);
624 error = xfs_inode_from_disk(ip,
625 xfs_buf_offset(bp, ip->i_imap.im_boffset));
627 xfs_buf_set_ref(bp, XFS_INO_REF);
628 xfs_trans_brelse(tp, bp);
634 trace_xfs_iget_miss(ip);
637 * Check the inode free state is valid. This also detects lookup
638 * racing with unlinks.
640 error = xfs_iget_check_free_state(ip, flags);
645 * Preload the radix tree so we can insert safely under the
646 * write spinlock. Note that we cannot sleep inside the preload
647 * region. Since we can be called from transaction context, don't
648 * recurse into the file system.
650 if (radix_tree_preload(GFP_NOFS)) {
656 * Because the inode hasn't been added to the radix-tree yet it can't
657 * be found by another thread, so we can do the non-sleeping lock here.
660 if (!xfs_ilock_nowait(ip, lock_flags))
665 * These values must be set before inserting the inode into the radix
666 * tree as the moment it is inserted a concurrent lookup (allowed by the
667 * RCU locking mechanism) can find it and that lookup must see that this
668 * is an inode currently under construction (i.e. that XFS_INEW is set).
669 * The ip->i_flags_lock that protects the XFS_INEW flag forms the
670 * memory barrier that ensures this detection works correctly at lookup
674 if (flags & XFS_IGET_DONTCACHE)
675 d_mark_dontcache(VFS_I(ip));
679 xfs_iflags_set(ip, iflags);
681 /* insert the new inode */
682 spin_lock(&pag->pag_ici_lock);
683 error = radix_tree_insert(&pag->pag_ici_root, agino, ip);
684 if (unlikely(error)) {
685 WARN_ON(error != -EEXIST);
686 XFS_STATS_INC(mp, xs_ig_dup);
688 goto out_preload_end;
690 spin_unlock(&pag->pag_ici_lock);
691 radix_tree_preload_end();
697 spin_unlock(&pag->pag_ici_lock);
698 radix_tree_preload_end();
700 xfs_iunlock(ip, lock_flags);
702 __destroy_inode(VFS_I(ip));
708 * Look up an inode by number in the given file system. The inode is looked up
709 * in the cache held in each AG. If the inode is found in the cache, initialise
710 * the vfs inode if necessary.
712 * If it is not in core, read it in from the file system's device, add it to the
713 * cache and initialise the vfs inode.
715 * The inode is locked according to the value of the lock_flags parameter.
716 * Inode lookup is only done during metadata operations and not as part of the
717 * data IO path. Hence we only allow locking of the XFS_ILOCK during lookup.
721 struct xfs_mount *mp,
722 struct xfs_trans *tp,
726 struct xfs_inode **ipp)
728 struct xfs_inode *ip;
729 struct xfs_perag *pag;
733 ASSERT((lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) == 0);
735 /* reject inode numbers outside existing AGs */
736 if (!ino || XFS_INO_TO_AGNO(mp, ino) >= mp->m_sb.sb_agcount)
739 XFS_STATS_INC(mp, xs_ig_attempts);
741 /* get the perag structure and ensure that it's inode capable */
742 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
743 agino = XFS_INO_TO_AGINO(mp, ino);
748 ip = radix_tree_lookup(&pag->pag_ici_root, agino);
751 error = xfs_iget_cache_hit(pag, ip, ino, flags, lock_flags);
753 goto out_error_or_again;
756 if (flags & XFS_IGET_INCORE) {
758 goto out_error_or_again;
760 XFS_STATS_INC(mp, xs_ig_missed);
762 error = xfs_iget_cache_miss(mp, pag, tp, ino, &ip,
765 goto out_error_or_again;
772 * If we have a real type for an on-disk inode, we can setup the inode
773 * now. If it's a new inode being created, xfs_ialloc will handle it.
775 if (xfs_iflags_test(ip, XFS_INEW) && VFS_I(ip)->i_mode != 0)
776 xfs_setup_existing_inode(ip);
780 if (!(flags & XFS_IGET_INCORE) && error == -EAGAIN) {
789 * "Is this a cached inode that's also allocated?"
791 * Look up an inode by number in the given file system. If the inode is
792 * in cache and isn't in purgatory, return 1 if the inode is allocated
793 * and 0 if it is not. For all other cases (not in cache, being torn
794 * down, etc.), return a negative error code.
796 * The caller has to prevent inode allocation and freeing activity,
797 * presumably by locking the AGI buffer. This is to ensure that an
798 * inode cannot transition from allocated to freed until the caller is
799 * ready to allow that. If the inode is in an intermediate state (new,
800 * reclaimable, or being reclaimed), -EAGAIN will be returned; if the
801 * inode is not in the cache, -ENOENT will be returned. The caller must
802 * deal with these scenarios appropriately.
804 * This is a specialized use case for the online scrubber; if you're
805 * reading this, you probably want xfs_iget.
808 xfs_icache_inode_is_allocated(
809 struct xfs_mount *mp,
810 struct xfs_trans *tp,
814 struct xfs_inode *ip;
817 error = xfs_iget(mp, tp, ino, XFS_IGET_INCORE, 0, &ip);
821 *inuse = !!(VFS_I(ip)->i_mode);
827 * Grab the inode for reclaim exclusively.
829 * We have found this inode via a lookup under RCU, so the inode may have
830 * already been freed, or it may be in the process of being recycled by
831 * xfs_iget(). In both cases, the inode will have XFS_IRECLAIM set. If the inode
832 * has been fully recycled by the time we get the i_flags_lock, XFS_IRECLAIMABLE
833 * will not be set. Hence we need to check for both these flag conditions to
834 * avoid inodes that are no longer reclaim candidates.
836 * Note: checking for other state flags here, under the i_flags_lock or not, is
837 * racy and should be avoided. Those races should be resolved only after we have
838 * ensured that we are able to reclaim this inode and the world can see that we
839 * are going to reclaim it.
841 * Return true if we grabbed it, false otherwise.
845 struct xfs_inode *ip,
846 struct xfs_icwalk *icw)
848 ASSERT(rcu_read_lock_held());
850 spin_lock(&ip->i_flags_lock);
851 if (!__xfs_iflags_test(ip, XFS_IRECLAIMABLE) ||
852 __xfs_iflags_test(ip, XFS_IRECLAIM)) {
853 /* not a reclaim candidate. */
854 spin_unlock(&ip->i_flags_lock);
858 /* Don't reclaim a sick inode unless the caller asked for it. */
860 (!icw || !(icw->icw_flags & XFS_ICWALK_FLAG_RECLAIM_SICK))) {
861 spin_unlock(&ip->i_flags_lock);
865 __xfs_iflags_set(ip, XFS_IRECLAIM);
866 spin_unlock(&ip->i_flags_lock);
871 * Inode reclaim is non-blocking, so the default action if progress cannot be
872 * made is to "requeue" the inode for reclaim by unlocking it and clearing the
873 * XFS_IRECLAIM flag. If we are in a shutdown state, we don't care about
874 * blocking anymore and hence we can wait for the inode to be able to reclaim
877 * We do no IO here - if callers require inodes to be cleaned they must push the
878 * AIL first to trigger writeback of dirty inodes. This enables writeback to be
879 * done in the background in a non-blocking manner, and enables memory reclaim
880 * to make progress without blocking.
884 struct xfs_inode *ip,
885 struct xfs_perag *pag)
887 xfs_ino_t ino = ip->i_ino; /* for radix_tree_delete */
889 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
891 if (xfs_iflags_test_and_set(ip, XFS_IFLUSHING))
894 if (xfs_is_shutdown(ip->i_mount)) {
896 xfs_iflush_abort(ip);
899 if (xfs_ipincount(ip))
900 goto out_clear_flush;
901 if (!xfs_inode_clean(ip))
902 goto out_clear_flush;
904 xfs_iflags_clear(ip, XFS_IFLUSHING);
906 trace_xfs_inode_reclaiming(ip);
909 * Because we use RCU freeing we need to ensure the inode always appears
910 * to be reclaimed with an invalid inode number when in the free state.
911 * We do this as early as possible under the ILOCK so that
912 * xfs_iflush_cluster() and xfs_ifree_cluster() can be guaranteed to
913 * detect races with us here. By doing this, we guarantee that once
914 * xfs_iflush_cluster() or xfs_ifree_cluster() has locked XFS_ILOCK that
915 * it will see either a valid inode that will serialise correctly, or it
916 * will see an invalid inode that it can skip.
918 spin_lock(&ip->i_flags_lock);
919 ip->i_flags = XFS_IRECLAIM;
923 spin_unlock(&ip->i_flags_lock);
925 xfs_iunlock(ip, XFS_ILOCK_EXCL);
927 XFS_STATS_INC(ip->i_mount, xs_ig_reclaims);
929 * Remove the inode from the per-AG radix tree.
931 * Because radix_tree_delete won't complain even if the item was never
932 * added to the tree assert that it's been there before to catch
933 * problems with the inode life time early on.
935 spin_lock(&pag->pag_ici_lock);
936 if (!radix_tree_delete(&pag->pag_ici_root,
937 XFS_INO_TO_AGINO(ip->i_mount, ino)))
939 xfs_perag_clear_inode_tag(pag, NULLAGINO, XFS_ICI_RECLAIM_TAG);
940 spin_unlock(&pag->pag_ici_lock);
943 * Here we do an (almost) spurious inode lock in order to coordinate
944 * with inode cache radix tree lookups. This is because the lookup
945 * can reference the inodes in the cache without taking references.
947 * We make that OK here by ensuring that we wait until the inode is
948 * unlocked after the lookup before we go ahead and free it.
950 xfs_ilock(ip, XFS_ILOCK_EXCL);
951 ASSERT(!ip->i_udquot && !ip->i_gdquot && !ip->i_pdquot);
952 xfs_iunlock(ip, XFS_ILOCK_EXCL);
953 ASSERT(xfs_inode_clean(ip));
955 __xfs_inode_free(ip);
959 xfs_iflags_clear(ip, XFS_IFLUSHING);
961 xfs_iunlock(ip, XFS_ILOCK_EXCL);
963 xfs_iflags_clear(ip, XFS_IRECLAIM);
966 /* Reclaim sick inodes if we're unmounting or the fs went down. */
968 xfs_want_reclaim_sick(
969 struct xfs_mount *mp)
971 return xfs_is_unmounting(mp) || xfs_has_norecovery(mp) ||
977 struct xfs_mount *mp)
979 struct xfs_icwalk icw = {
983 if (xfs_want_reclaim_sick(mp))
984 icw.icw_flags |= XFS_ICWALK_FLAG_RECLAIM_SICK;
986 while (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_RECLAIM_TAG)) {
987 xfs_ail_push_all_sync(mp->m_ail);
988 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, &icw);
993 * The shrinker infrastructure determines how many inodes we should scan for
994 * reclaim. We want as many clean inodes ready to reclaim as possible, so we
995 * push the AIL here. We also want to proactively free up memory if we can to
996 * minimise the amount of work memory reclaim has to do so we kick the
997 * background reclaim if it isn't already scheduled.
1000 xfs_reclaim_inodes_nr(
1001 struct xfs_mount *mp,
1002 unsigned long nr_to_scan)
1004 struct xfs_icwalk icw = {
1005 .icw_flags = XFS_ICWALK_FLAG_SCAN_LIMIT,
1006 .icw_scan_limit = min_t(unsigned long, LONG_MAX, nr_to_scan),
1009 if (xfs_want_reclaim_sick(mp))
1010 icw.icw_flags |= XFS_ICWALK_FLAG_RECLAIM_SICK;
1012 /* kick background reclaimer and push the AIL */
1013 xfs_reclaim_work_queue(mp);
1014 xfs_ail_push_all(mp->m_ail);
1016 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, &icw);
1021 * Return the number of reclaimable inodes in the filesystem for
1022 * the shrinker to determine how much to reclaim.
1025 xfs_reclaim_inodes_count(
1026 struct xfs_mount *mp)
1028 struct xfs_perag *pag;
1029 xfs_agnumber_t ag = 0;
1030 long reclaimable = 0;
1032 while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) {
1033 ag = pag->pag_agno + 1;
1034 reclaimable += pag->pag_ici_reclaimable;
1041 xfs_icwalk_match_id(
1042 struct xfs_inode *ip,
1043 struct xfs_icwalk *icw)
1045 if ((icw->icw_flags & XFS_ICWALK_FLAG_UID) &&
1046 !uid_eq(VFS_I(ip)->i_uid, icw->icw_uid))
1049 if ((icw->icw_flags & XFS_ICWALK_FLAG_GID) &&
1050 !gid_eq(VFS_I(ip)->i_gid, icw->icw_gid))
1053 if ((icw->icw_flags & XFS_ICWALK_FLAG_PRID) &&
1054 ip->i_projid != icw->icw_prid)
1061 * A union-based inode filtering algorithm. Process the inode if any of the
1062 * criteria match. This is for global/internal scans only.
1065 xfs_icwalk_match_id_union(
1066 struct xfs_inode *ip,
1067 struct xfs_icwalk *icw)
1069 if ((icw->icw_flags & XFS_ICWALK_FLAG_UID) &&
1070 uid_eq(VFS_I(ip)->i_uid, icw->icw_uid))
1073 if ((icw->icw_flags & XFS_ICWALK_FLAG_GID) &&
1074 gid_eq(VFS_I(ip)->i_gid, icw->icw_gid))
1077 if ((icw->icw_flags & XFS_ICWALK_FLAG_PRID) &&
1078 ip->i_projid == icw->icw_prid)
1085 * Is this inode @ip eligible for eof/cow block reclamation, given some
1086 * filtering parameters @icw? The inode is eligible if @icw is null or
1087 * if the predicate functions match.
1091 struct xfs_inode *ip,
1092 struct xfs_icwalk *icw)
1099 if (icw->icw_flags & XFS_ICWALK_FLAG_UNION)
1100 match = xfs_icwalk_match_id_union(ip, icw);
1102 match = xfs_icwalk_match_id(ip, icw);
1106 /* skip the inode if the file size is too small */
1107 if ((icw->icw_flags & XFS_ICWALK_FLAG_MINFILESIZE) &&
1108 XFS_ISIZE(ip) < icw->icw_min_file_size)
1115 * This is a fast pass over the inode cache to try to get reclaim moving on as
1116 * many inodes as possible in a short period of time. It kicks itself every few
1117 * seconds, as well as being kicked by the inode cache shrinker when memory
1122 struct work_struct *work)
1124 struct xfs_mount *mp = container_of(to_delayed_work(work),
1125 struct xfs_mount, m_reclaim_work);
1127 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, NULL);
1128 xfs_reclaim_work_queue(mp);
1132 xfs_inode_free_eofblocks(
1133 struct xfs_inode *ip,
1134 struct xfs_icwalk *icw,
1135 unsigned int *lockflags)
1139 wait = icw && (icw->icw_flags & XFS_ICWALK_FLAG_SYNC);
1141 if (!xfs_iflags_test(ip, XFS_IEOFBLOCKS))
1145 * If the mapping is dirty the operation can block and wait for some
1146 * time. Unless we are waiting, skip it.
1148 if (!wait && mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_DIRTY))
1151 if (!xfs_icwalk_match(ip, icw))
1155 * If the caller is waiting, return -EAGAIN to keep the background
1156 * scanner moving and revisit the inode in a subsequent pass.
1158 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1163 *lockflags |= XFS_IOLOCK_EXCL;
1165 if (xfs_can_free_eofblocks(ip, false))
1166 return xfs_free_eofblocks(ip);
1168 /* inode could be preallocated or append-only */
1169 trace_xfs_inode_free_eofblocks_invalid(ip);
1170 xfs_inode_clear_eofblocks_tag(ip);
1175 xfs_blockgc_set_iflag(
1176 struct xfs_inode *ip,
1177 unsigned long iflag)
1179 struct xfs_mount *mp = ip->i_mount;
1180 struct xfs_perag *pag;
1182 ASSERT((iflag & ~(XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0);
1185 * Don't bother locking the AG and looking up in the radix trees
1186 * if we already know that we have the tag set.
1188 if (ip->i_flags & iflag)
1190 spin_lock(&ip->i_flags_lock);
1191 ip->i_flags |= iflag;
1192 spin_unlock(&ip->i_flags_lock);
1194 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1195 spin_lock(&pag->pag_ici_lock);
1197 xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1198 XFS_ICI_BLOCKGC_TAG);
1200 spin_unlock(&pag->pag_ici_lock);
1205 xfs_inode_set_eofblocks_tag(
1208 trace_xfs_inode_set_eofblocks_tag(ip);
1209 return xfs_blockgc_set_iflag(ip, XFS_IEOFBLOCKS);
1213 xfs_blockgc_clear_iflag(
1214 struct xfs_inode *ip,
1215 unsigned long iflag)
1217 struct xfs_mount *mp = ip->i_mount;
1218 struct xfs_perag *pag;
1221 ASSERT((iflag & ~(XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0);
1223 spin_lock(&ip->i_flags_lock);
1224 ip->i_flags &= ~iflag;
1225 clear_tag = (ip->i_flags & (XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0;
1226 spin_unlock(&ip->i_flags_lock);
1231 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1232 spin_lock(&pag->pag_ici_lock);
1234 xfs_perag_clear_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1235 XFS_ICI_BLOCKGC_TAG);
1237 spin_unlock(&pag->pag_ici_lock);
1242 xfs_inode_clear_eofblocks_tag(
1245 trace_xfs_inode_clear_eofblocks_tag(ip);
1246 return xfs_blockgc_clear_iflag(ip, XFS_IEOFBLOCKS);
1250 * Set ourselves up to free CoW blocks from this file. If it's already clean
1251 * then we can bail out quickly, but otherwise we must back off if the file
1252 * is undergoing some kind of write.
1255 xfs_prep_free_cowblocks(
1256 struct xfs_inode *ip)
1259 * Just clear the tag if we have an empty cow fork or none at all. It's
1260 * possible the inode was fully unshared since it was originally tagged.
1262 if (!xfs_inode_has_cow_data(ip)) {
1263 trace_xfs_inode_free_cowblocks_invalid(ip);
1264 xfs_inode_clear_cowblocks_tag(ip);
1269 * If the mapping is dirty or under writeback we cannot touch the
1270 * CoW fork. Leave it alone if we're in the midst of a directio.
1272 if ((VFS_I(ip)->i_state & I_DIRTY_PAGES) ||
1273 mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_DIRTY) ||
1274 mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_WRITEBACK) ||
1275 atomic_read(&VFS_I(ip)->i_dio_count))
1282 * Automatic CoW Reservation Freeing
1284 * These functions automatically garbage collect leftover CoW reservations
1285 * that were made on behalf of a cowextsize hint when we start to run out
1286 * of quota or when the reservations sit around for too long. If the file
1287 * has dirty pages or is undergoing writeback, its CoW reservations will
1290 * The actual garbage collection piggybacks off the same code that runs
1291 * the speculative EOF preallocation garbage collector.
1294 xfs_inode_free_cowblocks(
1295 struct xfs_inode *ip,
1296 struct xfs_icwalk *icw,
1297 unsigned int *lockflags)
1302 wait = icw && (icw->icw_flags & XFS_ICWALK_FLAG_SYNC);
1304 if (!xfs_iflags_test(ip, XFS_ICOWBLOCKS))
1307 if (!xfs_prep_free_cowblocks(ip))
1310 if (!xfs_icwalk_match(ip, icw))
1314 * If the caller is waiting, return -EAGAIN to keep the background
1315 * scanner moving and revisit the inode in a subsequent pass.
1317 if (!(*lockflags & XFS_IOLOCK_EXCL) &&
1318 !xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1323 *lockflags |= XFS_IOLOCK_EXCL;
1325 if (!xfs_ilock_nowait(ip, XFS_MMAPLOCK_EXCL)) {
1330 *lockflags |= XFS_MMAPLOCK_EXCL;
1333 * Check again, nobody else should be able to dirty blocks or change
1334 * the reflink iflag now that we have the first two locks held.
1336 if (xfs_prep_free_cowblocks(ip))
1337 ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
1342 xfs_inode_set_cowblocks_tag(
1345 trace_xfs_inode_set_cowblocks_tag(ip);
1346 return xfs_blockgc_set_iflag(ip, XFS_ICOWBLOCKS);
1350 xfs_inode_clear_cowblocks_tag(
1353 trace_xfs_inode_clear_cowblocks_tag(ip);
1354 return xfs_blockgc_clear_iflag(ip, XFS_ICOWBLOCKS);
1357 /* Disable post-EOF and CoW block auto-reclamation. */
1360 struct xfs_mount *mp)
1362 struct xfs_perag *pag;
1363 xfs_agnumber_t agno;
1365 if (!xfs_clear_blockgc_enabled(mp))
1368 for_each_perag(mp, agno, pag)
1369 cancel_delayed_work_sync(&pag->pag_blockgc_work);
1370 trace_xfs_blockgc_stop(mp, __return_address);
1373 /* Enable post-EOF and CoW block auto-reclamation. */
1376 struct xfs_mount *mp)
1378 struct xfs_perag *pag;
1379 xfs_agnumber_t agno;
1381 if (xfs_set_blockgc_enabled(mp))
1384 trace_xfs_blockgc_start(mp, __return_address);
1385 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1386 xfs_blockgc_queue(pag);
1389 /* Don't try to run block gc on an inode that's in any of these states. */
1390 #define XFS_BLOCKGC_NOGRAB_IFLAGS (XFS_INEW | \
1391 XFS_NEED_INACTIVE | \
1392 XFS_INACTIVATING | \
1393 XFS_IRECLAIMABLE | \
1396 * Decide if the given @ip is eligible for garbage collection of speculative
1397 * preallocations, and grab it if so. Returns true if it's ready to go or
1398 * false if we should just ignore it.
1402 struct xfs_inode *ip)
1404 struct inode *inode = VFS_I(ip);
1406 ASSERT(rcu_read_lock_held());
1408 /* Check for stale RCU freed inode */
1409 spin_lock(&ip->i_flags_lock);
1411 goto out_unlock_noent;
1413 if (ip->i_flags & XFS_BLOCKGC_NOGRAB_IFLAGS)
1414 goto out_unlock_noent;
1415 spin_unlock(&ip->i_flags_lock);
1417 /* nothing to sync during shutdown */
1418 if (xfs_is_shutdown(ip->i_mount))
1421 /* If we can't grab the inode, it must on it's way to reclaim. */
1425 /* inode is valid */
1429 spin_unlock(&ip->i_flags_lock);
1433 /* Scan one incore inode for block preallocations that we can remove. */
1435 xfs_blockgc_scan_inode(
1436 struct xfs_inode *ip,
1437 struct xfs_icwalk *icw)
1439 unsigned int lockflags = 0;
1442 error = xfs_inode_free_eofblocks(ip, icw, &lockflags);
1446 error = xfs_inode_free_cowblocks(ip, icw, &lockflags);
1449 xfs_iunlock(ip, lockflags);
1454 /* Background worker that trims preallocated space. */
1457 struct work_struct *work)
1459 struct xfs_perag *pag = container_of(to_delayed_work(work),
1460 struct xfs_perag, pag_blockgc_work);
1461 struct xfs_mount *mp = pag->pag_mount;
1464 trace_xfs_blockgc_worker(mp, __return_address);
1466 error = xfs_icwalk_ag(pag, XFS_ICWALK_BLOCKGC, NULL);
1468 xfs_info(mp, "AG %u preallocation gc worker failed, err=%d",
1469 pag->pag_agno, error);
1470 xfs_blockgc_queue(pag);
1474 * Try to free space in the filesystem by purging inactive inodes, eofblocks
1478 xfs_blockgc_free_space(
1479 struct xfs_mount *mp,
1480 struct xfs_icwalk *icw)
1484 trace_xfs_blockgc_free_space(mp, icw, _RET_IP_);
1486 error = xfs_icwalk(mp, XFS_ICWALK_BLOCKGC, icw);
1490 xfs_inodegc_flush(mp);
1495 * Reclaim all the free space that we can by scheduling the background blockgc
1496 * and inodegc workers immediately and waiting for them all to clear.
1499 xfs_blockgc_flush_all(
1500 struct xfs_mount *mp)
1502 struct xfs_perag *pag;
1503 xfs_agnumber_t agno;
1505 trace_xfs_blockgc_flush_all(mp, __return_address);
1508 * For each blockgc worker, move its queue time up to now. If it
1509 * wasn't queued, it will not be requeued. Then flush whatever's
1512 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1513 mod_delayed_work(pag->pag_mount->m_blockgc_wq,
1514 &pag->pag_blockgc_work, 0);
1516 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1517 flush_delayed_work(&pag->pag_blockgc_work);
1519 xfs_inodegc_flush(mp);
1523 * Run cow/eofblocks scans on the supplied dquots. We don't know exactly which
1524 * quota caused an allocation failure, so we make a best effort by including
1525 * each quota under low free space conditions (less than 1% free space) in the
1528 * Callers must not hold any inode's ILOCK. If requesting a synchronous scan
1529 * (XFS_ICWALK_FLAG_SYNC), the caller also must not hold any inode's IOLOCK or
1533 xfs_blockgc_free_dquots(
1534 struct xfs_mount *mp,
1535 struct xfs_dquot *udqp,
1536 struct xfs_dquot *gdqp,
1537 struct xfs_dquot *pdqp,
1538 unsigned int iwalk_flags)
1540 struct xfs_icwalk icw = {0};
1541 bool do_work = false;
1543 if (!udqp && !gdqp && !pdqp)
1547 * Run a scan to free blocks using the union filter to cover all
1548 * applicable quotas in a single scan.
1550 icw.icw_flags = XFS_ICWALK_FLAG_UNION | iwalk_flags;
1552 if (XFS_IS_UQUOTA_ENFORCED(mp) && udqp && xfs_dquot_lowsp(udqp)) {
1553 icw.icw_uid = make_kuid(mp->m_super->s_user_ns, udqp->q_id);
1554 icw.icw_flags |= XFS_ICWALK_FLAG_UID;
1558 if (XFS_IS_UQUOTA_ENFORCED(mp) && gdqp && xfs_dquot_lowsp(gdqp)) {
1559 icw.icw_gid = make_kgid(mp->m_super->s_user_ns, gdqp->q_id);
1560 icw.icw_flags |= XFS_ICWALK_FLAG_GID;
1564 if (XFS_IS_PQUOTA_ENFORCED(mp) && pdqp && xfs_dquot_lowsp(pdqp)) {
1565 icw.icw_prid = pdqp->q_id;
1566 icw.icw_flags |= XFS_ICWALK_FLAG_PRID;
1573 return xfs_blockgc_free_space(mp, &icw);
1576 /* Run cow/eofblocks scans on the quotas attached to the inode. */
1578 xfs_blockgc_free_quota(
1579 struct xfs_inode *ip,
1580 unsigned int iwalk_flags)
1582 return xfs_blockgc_free_dquots(ip->i_mount,
1583 xfs_inode_dquot(ip, XFS_DQTYPE_USER),
1584 xfs_inode_dquot(ip, XFS_DQTYPE_GROUP),
1585 xfs_inode_dquot(ip, XFS_DQTYPE_PROJ), iwalk_flags);
1588 /* XFS Inode Cache Walking Code */
1591 * The inode lookup is done in batches to keep the amount of lock traffic and
1592 * radix tree lookups to a minimum. The batch size is a trade off between
1593 * lookup reduction and stack usage. This is in the reclaim path, so we can't
1596 #define XFS_LOOKUP_BATCH 32
1600 * Decide if we want to grab this inode in anticipation of doing work towards
1605 enum xfs_icwalk_goal goal,
1606 struct xfs_inode *ip,
1607 struct xfs_icwalk *icw)
1610 case XFS_ICWALK_BLOCKGC:
1611 return xfs_blockgc_igrab(ip);
1612 case XFS_ICWALK_RECLAIM:
1613 return xfs_reclaim_igrab(ip, icw);
1620 * Process an inode. Each processing function must handle any state changes
1621 * made by the icwalk igrab function. Return -EAGAIN to skip an inode.
1624 xfs_icwalk_process_inode(
1625 enum xfs_icwalk_goal goal,
1626 struct xfs_inode *ip,
1627 struct xfs_perag *pag,
1628 struct xfs_icwalk *icw)
1633 case XFS_ICWALK_BLOCKGC:
1634 error = xfs_blockgc_scan_inode(ip, icw);
1636 case XFS_ICWALK_RECLAIM:
1637 xfs_reclaim_inode(ip, pag);
1644 * For a given per-AG structure @pag and a goal, grab qualifying inodes and
1645 * process them in some manner.
1649 struct xfs_perag *pag,
1650 enum xfs_icwalk_goal goal,
1651 struct xfs_icwalk *icw)
1653 struct xfs_mount *mp = pag->pag_mount;
1654 uint32_t first_index;
1663 if (goal == XFS_ICWALK_RECLAIM)
1664 first_index = READ_ONCE(pag->pag_ici_reclaim_cursor);
1669 struct xfs_inode *batch[XFS_LOOKUP_BATCH];
1675 nr_found = radix_tree_gang_lookup_tag(&pag->pag_ici_root,
1676 (void **) batch, first_index,
1677 XFS_LOOKUP_BATCH, goal);
1685 * Grab the inodes before we drop the lock. if we found
1686 * nothing, nr == 0 and the loop will be skipped.
1688 for (i = 0; i < nr_found; i++) {
1689 struct xfs_inode *ip = batch[i];
1691 if (done || !xfs_icwalk_igrab(goal, ip, icw))
1695 * Update the index for the next lookup. Catch
1696 * overflows into the next AG range which can occur if
1697 * we have inodes in the last block of the AG and we
1698 * are currently pointing to the last inode.
1700 * Because we may see inodes that are from the wrong AG
1701 * due to RCU freeing and reallocation, only update the
1702 * index if it lies in this AG. It was a race that lead
1703 * us to see this inode, so another lookup from the
1704 * same index will not find it again.
1706 if (XFS_INO_TO_AGNO(mp, ip->i_ino) != pag->pag_agno)
1708 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
1709 if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino))
1713 /* unlock now we've grabbed the inodes. */
1716 for (i = 0; i < nr_found; i++) {
1719 error = xfs_icwalk_process_inode(goal, batch[i], pag,
1721 if (error == -EAGAIN) {
1725 if (error && last_error != -EFSCORRUPTED)
1729 /* bail out if the filesystem is corrupted. */
1730 if (error == -EFSCORRUPTED)
1735 if (icw && (icw->icw_flags & XFS_ICWALK_FLAG_SCAN_LIMIT)) {
1736 icw->icw_scan_limit -= XFS_LOOKUP_BATCH;
1737 if (icw->icw_scan_limit <= 0)
1740 } while (nr_found && !done);
1742 if (goal == XFS_ICWALK_RECLAIM) {
1745 WRITE_ONCE(pag->pag_ici_reclaim_cursor, first_index);
1755 /* Walk all incore inodes to achieve a given goal. */
1758 struct xfs_mount *mp,
1759 enum xfs_icwalk_goal goal,
1760 struct xfs_icwalk *icw)
1762 struct xfs_perag *pag;
1765 xfs_agnumber_t agno;
1767 for_each_perag_tag(mp, agno, pag, goal) {
1768 error = xfs_icwalk_ag(pag, goal, icw);
1771 if (error == -EFSCORRUPTED) {
1778 BUILD_BUG_ON(XFS_ICWALK_PRIVATE_FLAGS & XFS_ICWALK_FLAGS_VALID);
1784 struct xfs_inode *ip,
1787 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
1788 struct xfs_bmbt_irec got;
1789 struct xfs_iext_cursor icur;
1791 if (!ifp || !xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got))
1794 if (isnullstartblock(got.br_startblock)) {
1795 xfs_warn(ip->i_mount,
1796 "ino %llx %s fork has delalloc extent at [0x%llx:0x%llx]",
1798 whichfork == XFS_DATA_FORK ? "data" : "cow",
1799 got.br_startoff, got.br_blockcount);
1801 } while (xfs_iext_next_extent(ifp, &icur, &got));
1804 #define xfs_check_delalloc(ip, whichfork) do { } while (0)
1807 /* Schedule the inode for reclaim. */
1809 xfs_inodegc_set_reclaimable(
1810 struct xfs_inode *ip)
1812 struct xfs_mount *mp = ip->i_mount;
1813 struct xfs_perag *pag;
1815 if (!xfs_is_shutdown(mp) && ip->i_delayed_blks) {
1816 xfs_check_delalloc(ip, XFS_DATA_FORK);
1817 xfs_check_delalloc(ip, XFS_COW_FORK);
1821 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1822 spin_lock(&pag->pag_ici_lock);
1823 spin_lock(&ip->i_flags_lock);
1825 trace_xfs_inode_set_reclaimable(ip);
1826 ip->i_flags &= ~(XFS_NEED_INACTIVE | XFS_INACTIVATING);
1827 ip->i_flags |= XFS_IRECLAIMABLE;
1828 xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1829 XFS_ICI_RECLAIM_TAG);
1831 spin_unlock(&ip->i_flags_lock);
1832 spin_unlock(&pag->pag_ici_lock);
1837 * Free all speculative preallocations and possibly even the inode itself.
1838 * This is the last chance to make changes to an otherwise unreferenced file
1839 * before incore reclamation happens.
1842 xfs_inodegc_inactivate(
1843 struct xfs_inode *ip)
1845 trace_xfs_inode_inactivating(ip);
1847 xfs_inodegc_set_reclaimable(ip);
1852 struct work_struct *work)
1854 struct xfs_inodegc *gc = container_of(work, struct xfs_inodegc,
1856 struct llist_node *node = llist_del_all(&gc->list);
1857 struct xfs_inode *ip, *n;
1859 WRITE_ONCE(gc->items, 0);
1864 ip = llist_entry(node, struct xfs_inode, i_gclist);
1865 trace_xfs_inodegc_worker(ip->i_mount, READ_ONCE(gc->shrinker_hits));
1867 WRITE_ONCE(gc->shrinker_hits, 0);
1868 llist_for_each_entry_safe(ip, n, node, i_gclist) {
1869 xfs_iflags_set(ip, XFS_INACTIVATING);
1870 xfs_inodegc_inactivate(ip);
1875 * Force all currently queued inode inactivation work to run immediately, and
1876 * wait for the work to finish. Two pass - queue all the work first pass, wait
1877 * for it in a second pass.
1881 struct xfs_mount *mp)
1883 struct xfs_inodegc *gc;
1886 if (!xfs_is_inodegc_enabled(mp))
1889 trace_xfs_inodegc_flush(mp, __return_address);
1891 xfs_inodegc_queue_all(mp);
1893 for_each_online_cpu(cpu) {
1894 gc = per_cpu_ptr(mp->m_inodegc, cpu);
1895 flush_work(&gc->work);
1900 * Flush all the pending work and then disable the inode inactivation background
1901 * workers and wait for them to stop.
1905 struct xfs_mount *mp)
1907 struct xfs_inodegc *gc;
1910 if (!xfs_clear_inodegc_enabled(mp))
1913 xfs_inodegc_queue_all(mp);
1915 for_each_online_cpu(cpu) {
1916 gc = per_cpu_ptr(mp->m_inodegc, cpu);
1917 cancel_work_sync(&gc->work);
1919 trace_xfs_inodegc_stop(mp, __return_address);
1923 * Enable the inode inactivation background workers and schedule deferred inode
1924 * inactivation work if there is any.
1928 struct xfs_mount *mp)
1930 if (xfs_set_inodegc_enabled(mp))
1933 trace_xfs_inodegc_start(mp, __return_address);
1934 xfs_inodegc_queue_all(mp);
1937 #ifdef CONFIG_XFS_RT
1939 xfs_inodegc_want_queue_rt_file(
1940 struct xfs_inode *ip)
1942 struct xfs_mount *mp = ip->i_mount;
1945 if (!XFS_IS_REALTIME_INODE(ip))
1948 freertx = READ_ONCE(mp->m_sb.sb_frextents);
1949 return freertx < mp->m_low_rtexts[XFS_LOWSP_5_PCNT];
1952 # define xfs_inodegc_want_queue_rt_file(ip) (false)
1953 #endif /* CONFIG_XFS_RT */
1956 * Schedule the inactivation worker when:
1958 * - We've accumulated more than one inode cluster buffer's worth of inodes.
1959 * - There is less than 5% free space left.
1960 * - Any of the quotas for this inode are near an enforcement limit.
1963 xfs_inodegc_want_queue_work(
1964 struct xfs_inode *ip,
1967 struct xfs_mount *mp = ip->i_mount;
1969 if (items > mp->m_ino_geo.inodes_per_cluster)
1972 if (__percpu_counter_compare(&mp->m_fdblocks,
1973 mp->m_low_space[XFS_LOWSP_5_PCNT],
1974 XFS_FDBLOCKS_BATCH) < 0)
1977 if (xfs_inodegc_want_queue_rt_file(ip))
1980 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_USER))
1983 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_GROUP))
1986 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_PROJ))
1993 * Upper bound on the number of inodes in each AG that can be queued for
1994 * inactivation at any given time, to avoid monopolizing the workqueue.
1996 #define XFS_INODEGC_MAX_BACKLOG (4 * XFS_INODES_PER_CHUNK)
1999 * Make the frontend wait for inactivations when:
2001 * - Memory shrinkers queued the inactivation worker and it hasn't finished.
2002 * - The queue depth exceeds the maximum allowable percpu backlog.
2004 * Note: If the current thread is running a transaction, we don't ever want to
2005 * wait for other transactions because that could introduce a deadlock.
2008 xfs_inodegc_want_flush_work(
2009 struct xfs_inode *ip,
2011 unsigned int shrinker_hits)
2013 if (current->journal_info)
2016 if (shrinker_hits > 0)
2019 if (items > XFS_INODEGC_MAX_BACKLOG)
2026 * Queue a background inactivation worker if there are inodes that need to be
2027 * inactivated and higher level xfs code hasn't disabled the background
2032 struct xfs_inode *ip)
2034 struct xfs_mount *mp = ip->i_mount;
2035 struct xfs_inodegc *gc;
2037 unsigned int shrinker_hits;
2039 trace_xfs_inode_set_need_inactive(ip);
2040 spin_lock(&ip->i_flags_lock);
2041 ip->i_flags |= XFS_NEED_INACTIVE;
2042 spin_unlock(&ip->i_flags_lock);
2044 gc = get_cpu_ptr(mp->m_inodegc);
2045 llist_add(&ip->i_gclist, &gc->list);
2046 items = READ_ONCE(gc->items);
2047 WRITE_ONCE(gc->items, items + 1);
2048 shrinker_hits = READ_ONCE(gc->shrinker_hits);
2051 if (!xfs_is_inodegc_enabled(mp))
2054 if (xfs_inodegc_want_queue_work(ip, items)) {
2055 trace_xfs_inodegc_queue(mp, __return_address);
2056 queue_work(mp->m_inodegc_wq, &gc->work);
2059 if (xfs_inodegc_want_flush_work(ip, items, shrinker_hits)) {
2060 trace_xfs_inodegc_throttle(mp, __return_address);
2061 flush_work(&gc->work);
2066 * Fold the dead CPU inodegc queue into the current CPUs queue.
2069 xfs_inodegc_cpu_dead(
2070 struct xfs_mount *mp,
2071 unsigned int dead_cpu)
2073 struct xfs_inodegc *dead_gc, *gc;
2074 struct llist_node *first, *last;
2075 unsigned int count = 0;
2077 dead_gc = per_cpu_ptr(mp->m_inodegc, dead_cpu);
2078 cancel_work_sync(&dead_gc->work);
2080 if (llist_empty(&dead_gc->list))
2083 first = dead_gc->list.first;
2085 while (last->next) {
2089 dead_gc->list.first = NULL;
2092 /* Add pending work to current CPU */
2093 gc = get_cpu_ptr(mp->m_inodegc);
2094 llist_add_batch(first, last, &gc->list);
2095 count += READ_ONCE(gc->items);
2096 WRITE_ONCE(gc->items, count);
2099 if (xfs_is_inodegc_enabled(mp)) {
2100 trace_xfs_inodegc_queue(mp, __return_address);
2101 queue_work(mp->m_inodegc_wq, &gc->work);
2106 * We set the inode flag atomically with the radix tree tag. Once we get tag
2107 * lookups on the radix tree, this inode flag can go away.
2109 * We always use background reclaim here because even if the inode is clean, it
2110 * still may be under IO and hence we have wait for IO completion to occur
2111 * before we can reclaim the inode. The background reclaim path handles this
2112 * more efficiently than we can here, so simply let background reclaim tear down
2116 xfs_inode_mark_reclaimable(
2117 struct xfs_inode *ip)
2119 struct xfs_mount *mp = ip->i_mount;
2122 XFS_STATS_INC(mp, vn_reclaim);
2125 * We should never get here with any of the reclaim flags already set.
2127 ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_ALL_IRECLAIM_FLAGS));
2129 need_inactive = xfs_inode_needs_inactive(ip);
2130 if (need_inactive) {
2131 xfs_inodegc_queue(ip);
2135 /* Going straight to reclaim, so drop the dquots. */
2136 xfs_qm_dqdetach(ip);
2137 xfs_inodegc_set_reclaimable(ip);
2141 * Register a phony shrinker so that we can run background inodegc sooner when
2142 * there's memory pressure. Inactivation does not itself free any memory but
2143 * it does make inodes reclaimable, which eventually frees memory.
2145 * The count function, seek value, and batch value are crafted to trigger the
2146 * scan function during the second round of scanning. Hopefully this means
2147 * that we reclaimed enough memory that initiating metadata transactions won't
2148 * make things worse.
2150 #define XFS_INODEGC_SHRINKER_COUNT (1UL << DEF_PRIORITY)
2151 #define XFS_INODEGC_SHRINKER_BATCH ((XFS_INODEGC_SHRINKER_COUNT / 2) + 1)
2153 static unsigned long
2154 xfs_inodegc_shrinker_count(
2155 struct shrinker *shrink,
2156 struct shrink_control *sc)
2158 struct xfs_mount *mp = container_of(shrink, struct xfs_mount,
2159 m_inodegc_shrinker);
2160 struct xfs_inodegc *gc;
2163 if (!xfs_is_inodegc_enabled(mp))
2166 for_each_online_cpu(cpu) {
2167 gc = per_cpu_ptr(mp->m_inodegc, cpu);
2168 if (!llist_empty(&gc->list))
2169 return XFS_INODEGC_SHRINKER_COUNT;
2175 static unsigned long
2176 xfs_inodegc_shrinker_scan(
2177 struct shrinker *shrink,
2178 struct shrink_control *sc)
2180 struct xfs_mount *mp = container_of(shrink, struct xfs_mount,
2181 m_inodegc_shrinker);
2182 struct xfs_inodegc *gc;
2184 bool no_items = true;
2186 if (!xfs_is_inodegc_enabled(mp))
2189 trace_xfs_inodegc_shrinker_scan(mp, sc, __return_address);
2191 for_each_online_cpu(cpu) {
2192 gc = per_cpu_ptr(mp->m_inodegc, cpu);
2193 if (!llist_empty(&gc->list)) {
2194 unsigned int h = READ_ONCE(gc->shrinker_hits);
2196 WRITE_ONCE(gc->shrinker_hits, h + 1);
2197 queue_work_on(cpu, mp->m_inodegc_wq, &gc->work);
2203 * If there are no inodes to inactivate, we don't want the shrinker
2204 * to think there's deferred work to call us back about.
2212 /* Register a shrinker so we can accelerate inodegc and throttle queuing. */
2214 xfs_inodegc_register_shrinker(
2215 struct xfs_mount *mp)
2217 struct shrinker *shrink = &mp->m_inodegc_shrinker;
2219 shrink->count_objects = xfs_inodegc_shrinker_count;
2220 shrink->scan_objects = xfs_inodegc_shrinker_scan;
2222 shrink->flags = SHRINKER_NONSLAB;
2223 shrink->batch = XFS_INODEGC_SHRINKER_BATCH;
2225 return register_shrinker(shrink);