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"
26 #include "xfs_log_priv.h"
27 #include "xfs_health.h"
29 #include <linux/iversion.h>
31 /* Radix tree tags for incore inode tree. */
33 /* inode is to be reclaimed */
34 #define XFS_ICI_RECLAIM_TAG 0
35 /* Inode has speculative preallocations (posteof or cow) to clean. */
36 #define XFS_ICI_BLOCKGC_TAG 1
39 * The goal for walking incore inodes. These can correspond with incore inode
40 * radix tree tags when convenient. Avoid existing XFS_IWALK namespace.
42 enum xfs_icwalk_goal {
43 /* Goals directly associated with tagged inodes. */
44 XFS_ICWALK_BLOCKGC = XFS_ICI_BLOCKGC_TAG,
45 XFS_ICWALK_RECLAIM = XFS_ICI_RECLAIM_TAG,
48 static int xfs_icwalk(struct xfs_mount *mp,
49 enum xfs_icwalk_goal goal, struct xfs_icwalk *icw);
50 static int xfs_icwalk_ag(struct xfs_perag *pag,
51 enum xfs_icwalk_goal goal, struct xfs_icwalk *icw);
54 * Private inode cache walk flags for struct xfs_icwalk. Must not
55 * coincide with XFS_ICWALK_FLAGS_VALID.
58 /* Stop scanning after icw_scan_limit inodes. */
59 #define XFS_ICWALK_FLAG_SCAN_LIMIT (1U << 28)
61 #define XFS_ICWALK_FLAG_RECLAIM_SICK (1U << 27)
62 #define XFS_ICWALK_FLAG_UNION (1U << 26) /* union filter algorithm */
64 #define XFS_ICWALK_PRIVATE_FLAGS (XFS_ICWALK_FLAG_SCAN_LIMIT | \
65 XFS_ICWALK_FLAG_RECLAIM_SICK | \
66 XFS_ICWALK_FLAG_UNION)
69 * Allocate and initialise an xfs_inode.
79 * XXX: If this didn't occur in transactions, we could drop GFP_NOFAIL
80 * and return NULL here on ENOMEM.
82 ip = alloc_inode_sb(mp->m_super, xfs_inode_cache, GFP_KERNEL | __GFP_NOFAIL);
84 if (inode_init_always(mp->m_super, VFS_I(ip))) {
85 kmem_cache_free(xfs_inode_cache, ip);
89 /* VFS doesn't initialise i_mode or i_state! */
90 VFS_I(ip)->i_mode = 0;
91 VFS_I(ip)->i_state = 0;
92 mapping_set_large_folios(VFS_I(ip)->i_mapping);
94 XFS_STATS_INC(mp, vn_active);
95 ASSERT(atomic_read(&ip->i_pincount) == 0);
96 ASSERT(ip->i_ino == 0);
98 /* initialise the xfs inode */
101 memset(&ip->i_imap, 0, sizeof(struct xfs_imap));
103 memset(&ip->i_af, 0, sizeof(ip->i_af));
104 ip->i_af.if_format = XFS_DINODE_FMT_EXTENTS;
105 memset(&ip->i_df, 0, sizeof(ip->i_df));
107 ip->i_delayed_blks = 0;
108 ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
113 INIT_WORK(&ip->i_ioend_work, xfs_end_io);
114 INIT_LIST_HEAD(&ip->i_ioend_list);
115 spin_lock_init(&ip->i_ioend_lock);
116 ip->i_next_unlinked = NULLAGINO;
117 ip->i_prev_unlinked = 0;
123 xfs_inode_free_callback(
124 struct rcu_head *head)
126 struct inode *inode = container_of(head, struct inode, i_rcu);
127 struct xfs_inode *ip = XFS_I(inode);
129 switch (VFS_I(ip)->i_mode & S_IFMT) {
133 xfs_idestroy_fork(&ip->i_df);
137 xfs_ifork_zap_attr(ip);
140 xfs_idestroy_fork(ip->i_cowfp);
141 kmem_cache_free(xfs_ifork_cache, ip->i_cowfp);
144 ASSERT(!test_bit(XFS_LI_IN_AIL,
145 &ip->i_itemp->ili_item.li_flags));
146 xfs_inode_item_destroy(ip);
150 kmem_cache_free(xfs_inode_cache, ip);
155 struct xfs_inode *ip)
157 /* asserts to verify all state is correct here */
158 ASSERT(atomic_read(&ip->i_pincount) == 0);
159 ASSERT(!ip->i_itemp || list_empty(&ip->i_itemp->ili_item.li_bio_list));
160 XFS_STATS_DEC(ip->i_mount, vn_active);
162 call_rcu(&VFS_I(ip)->i_rcu, xfs_inode_free_callback);
167 struct xfs_inode *ip)
169 ASSERT(!xfs_iflags_test(ip, XFS_IFLUSHING));
172 * Because we use RCU freeing we need to ensure the inode always
173 * appears to be reclaimed with an invalid inode number when in the
174 * free state. The ip->i_flags_lock provides the barrier against lookup
177 spin_lock(&ip->i_flags_lock);
178 ip->i_flags = XFS_IRECLAIM;
180 spin_unlock(&ip->i_flags_lock);
182 __xfs_inode_free(ip);
186 * Queue background inode reclaim work if there are reclaimable inodes and there
187 * isn't reclaim work already scheduled or in progress.
190 xfs_reclaim_work_queue(
191 struct xfs_mount *mp)
195 if (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_RECLAIM_TAG)) {
196 queue_delayed_work(mp->m_reclaim_workqueue, &mp->m_reclaim_work,
197 msecs_to_jiffies(xfs_syncd_centisecs / 6 * 10));
203 * Background scanning to trim preallocated space. This is queued based on the
204 * 'speculative_prealloc_lifetime' tunable (5m by default).
208 struct xfs_perag *pag)
210 struct xfs_mount *mp = pag->pag_mount;
212 if (!xfs_is_blockgc_enabled(mp))
216 if (radix_tree_tagged(&pag->pag_ici_root, XFS_ICI_BLOCKGC_TAG))
217 queue_delayed_work(pag->pag_mount->m_blockgc_wq,
218 &pag->pag_blockgc_work,
219 msecs_to_jiffies(xfs_blockgc_secs * 1000));
223 /* Set a tag on both the AG incore inode tree and the AG radix tree. */
225 xfs_perag_set_inode_tag(
226 struct xfs_perag *pag,
230 struct xfs_mount *mp = pag->pag_mount;
233 lockdep_assert_held(&pag->pag_ici_lock);
235 was_tagged = radix_tree_tagged(&pag->pag_ici_root, tag);
236 radix_tree_tag_set(&pag->pag_ici_root, agino, tag);
238 if (tag == XFS_ICI_RECLAIM_TAG)
239 pag->pag_ici_reclaimable++;
244 /* propagate the tag up into the perag radix tree */
245 spin_lock(&mp->m_perag_lock);
246 radix_tree_tag_set(&mp->m_perag_tree, pag->pag_agno, tag);
247 spin_unlock(&mp->m_perag_lock);
249 /* start background work */
251 case XFS_ICI_RECLAIM_TAG:
252 xfs_reclaim_work_queue(mp);
254 case XFS_ICI_BLOCKGC_TAG:
255 xfs_blockgc_queue(pag);
259 trace_xfs_perag_set_inode_tag(pag, _RET_IP_);
262 /* Clear a tag on both the AG incore inode tree and the AG radix tree. */
264 xfs_perag_clear_inode_tag(
265 struct xfs_perag *pag,
269 struct xfs_mount *mp = pag->pag_mount;
271 lockdep_assert_held(&pag->pag_ici_lock);
274 * Reclaim can signal (with a null agino) that it cleared its own tag
275 * by removing the inode from the radix tree.
277 if (agino != NULLAGINO)
278 radix_tree_tag_clear(&pag->pag_ici_root, agino, tag);
280 ASSERT(tag == XFS_ICI_RECLAIM_TAG);
282 if (tag == XFS_ICI_RECLAIM_TAG)
283 pag->pag_ici_reclaimable--;
285 if (radix_tree_tagged(&pag->pag_ici_root, tag))
288 /* clear the tag from the perag radix tree */
289 spin_lock(&mp->m_perag_lock);
290 radix_tree_tag_clear(&mp->m_perag_tree, pag->pag_agno, tag);
291 spin_unlock(&mp->m_perag_lock);
293 trace_xfs_perag_clear_inode_tag(pag, _RET_IP_);
297 * When we recycle a reclaimable inode, we need to re-initialise the VFS inode
298 * part of the structure. This is made more complex by the fact we store
299 * information about the on-disk values in the VFS inode and so we can't just
300 * overwrite the values unconditionally. Hence we save the parameters we
301 * need to retain across reinitialisation, and rewrite them into the VFS inode
302 * after reinitialisation even if it fails.
306 struct xfs_mount *mp,
310 uint32_t nlink = inode->i_nlink;
311 uint32_t generation = inode->i_generation;
312 uint64_t version = inode_peek_iversion(inode);
313 umode_t mode = inode->i_mode;
314 dev_t dev = inode->i_rdev;
315 kuid_t uid = inode->i_uid;
316 kgid_t gid = inode->i_gid;
318 error = inode_init_always(mp->m_super, inode);
320 set_nlink(inode, nlink);
321 inode->i_generation = generation;
322 inode_set_iversion_queried(inode, version);
323 inode->i_mode = mode;
327 mapping_set_large_folios(inode->i_mapping);
332 * Carefully nudge an inode whose VFS state has been torn down back into a
333 * usable state. Drops the i_flags_lock and the rcu read lock.
337 struct xfs_perag *pag,
338 struct xfs_inode *ip) __releases(&ip->i_flags_lock)
340 struct xfs_mount *mp = ip->i_mount;
341 struct inode *inode = VFS_I(ip);
344 trace_xfs_iget_recycle(ip);
346 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
350 * We need to make it look like the inode is being reclaimed to prevent
351 * the actual reclaim workers from stomping over us while we recycle
352 * the inode. We can't clear the radix tree tag yet as it requires
353 * pag_ici_lock to be held exclusive.
355 ip->i_flags |= XFS_IRECLAIM;
357 spin_unlock(&ip->i_flags_lock);
360 ASSERT(!rwsem_is_locked(&inode->i_rwsem));
361 error = xfs_reinit_inode(mp, inode);
362 xfs_iunlock(ip, XFS_ILOCK_EXCL);
365 * Re-initializing the inode failed, and we are in deep
366 * trouble. Try to re-add it to the reclaim list.
369 spin_lock(&ip->i_flags_lock);
370 ip->i_flags &= ~(XFS_INEW | XFS_IRECLAIM);
371 ASSERT(ip->i_flags & XFS_IRECLAIMABLE);
372 spin_unlock(&ip->i_flags_lock);
375 trace_xfs_iget_recycle_fail(ip);
379 spin_lock(&pag->pag_ici_lock);
380 spin_lock(&ip->i_flags_lock);
383 * Clear the per-lifetime state in the inode as we are now effectively
384 * a new inode and need to return to the initial state before reuse
387 ip->i_flags &= ~XFS_IRECLAIM_RESET_FLAGS;
388 ip->i_flags |= XFS_INEW;
389 xfs_perag_clear_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
390 XFS_ICI_RECLAIM_TAG);
391 inode->i_state = I_NEW;
392 spin_unlock(&ip->i_flags_lock);
393 spin_unlock(&pag->pag_ici_lock);
399 * If we are allocating a new inode, then check what was returned is
400 * actually a free, empty inode. If we are not allocating an inode,
401 * then check we didn't find a free inode.
404 * 0 if the inode free state matches the lookup context
405 * -ENOENT if the inode is free and we are not allocating
406 * -EFSCORRUPTED if there is any state mismatch at all
409 xfs_iget_check_free_state(
410 struct xfs_inode *ip,
413 if (flags & XFS_IGET_CREATE) {
414 /* should be a free inode */
415 if (VFS_I(ip)->i_mode != 0) {
416 xfs_warn(ip->i_mount,
417 "Corruption detected! Free inode 0x%llx not marked free! (mode 0x%x)",
418 ip->i_ino, VFS_I(ip)->i_mode);
419 xfs_agno_mark_sick(ip->i_mount,
420 XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino),
422 return -EFSCORRUPTED;
425 if (ip->i_nblocks != 0) {
426 xfs_warn(ip->i_mount,
427 "Corruption detected! Free inode 0x%llx has blocks allocated!",
429 xfs_agno_mark_sick(ip->i_mount,
430 XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino),
432 return -EFSCORRUPTED;
437 /* should be an allocated inode */
438 if (VFS_I(ip)->i_mode == 0)
444 /* Make all pending inactivation work start immediately. */
446 xfs_inodegc_queue_all(
447 struct xfs_mount *mp)
449 struct xfs_inodegc *gc;
453 for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
454 gc = per_cpu_ptr(mp->m_inodegc, cpu);
455 if (!llist_empty(&gc->list)) {
456 mod_delayed_work_on(cpu, mp->m_inodegc_wq, &gc->work, 0);
464 /* Wait for all queued work and collect errors */
466 xfs_inodegc_wait_all(
467 struct xfs_mount *mp)
472 flush_workqueue(mp->m_inodegc_wq);
473 for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
474 struct xfs_inodegc *gc;
476 gc = per_cpu_ptr(mp->m_inodegc, cpu);
477 if (gc->error && !error)
486 * Check the validity of the inode we just found it the cache
490 struct xfs_perag *pag,
491 struct xfs_inode *ip,
494 int lock_flags) __releases(RCU)
496 struct inode *inode = VFS_I(ip);
497 struct xfs_mount *mp = ip->i_mount;
501 * check for re-use of an inode within an RCU grace period due to the
502 * radix tree nodes not being updated yet. We monitor for this by
503 * setting the inode number to zero before freeing the inode structure.
504 * If the inode has been reallocated and set up, then the inode number
505 * will not match, so check for that, too.
507 spin_lock(&ip->i_flags_lock);
508 if (ip->i_ino != ino)
512 * If we are racing with another cache hit that is currently
513 * instantiating this inode or currently recycling it out of
514 * reclaimable state, wait for the initialisation to complete
517 * If we're racing with the inactivation worker we also want to wait.
518 * If we're creating a new file, it's possible that the worker
519 * previously marked the inode as free on disk but hasn't finished
520 * updating the incore state yet. The AGI buffer will be dirty and
521 * locked to the icreate transaction, so a synchronous push of the
522 * inodegc workers would result in deadlock. For a regular iget, the
523 * worker is running already, so we might as well wait.
525 * XXX(hch): eventually we should do something equivalent to
526 * wait_on_inode to wait for these flags to be cleared
527 * instead of polling for it.
529 if (ip->i_flags & (XFS_INEW | XFS_IRECLAIM | XFS_INACTIVATING))
532 if (ip->i_flags & XFS_NEED_INACTIVE) {
533 /* Unlinked inodes cannot be re-grabbed. */
534 if (VFS_I(ip)->i_nlink == 0) {
538 goto out_inodegc_flush;
542 * Check the inode free state is valid. This also detects lookup
543 * racing with unlinks.
545 error = xfs_iget_check_free_state(ip, flags);
549 /* Skip inodes that have no vfs state. */
550 if ((flags & XFS_IGET_INCORE) &&
551 (ip->i_flags & XFS_IRECLAIMABLE))
554 /* The inode fits the selection criteria; process it. */
555 if (ip->i_flags & XFS_IRECLAIMABLE) {
556 /* Drops i_flags_lock and RCU read lock. */
557 error = xfs_iget_recycle(pag, ip);
558 if (error == -EAGAIN)
563 /* If the VFS inode is being torn down, pause and try again. */
567 /* We've got a live one. */
568 spin_unlock(&ip->i_flags_lock);
570 trace_xfs_iget_hit(ip);
574 xfs_ilock(ip, lock_flags);
576 if (!(flags & XFS_IGET_INCORE))
577 xfs_iflags_clear(ip, XFS_ISTALE);
578 XFS_STATS_INC(mp, xs_ig_found);
583 trace_xfs_iget_skip(ip);
584 XFS_STATS_INC(mp, xs_ig_frecycle);
587 spin_unlock(&ip->i_flags_lock);
592 spin_unlock(&ip->i_flags_lock);
595 * Do not wait for the workers, because the caller could hold an AGI
596 * buffer lock. We're just going to sleep in a loop anyway.
598 if (xfs_is_inodegc_enabled(mp))
599 xfs_inodegc_queue_all(mp);
605 struct xfs_mount *mp,
606 struct xfs_perag *pag,
609 struct xfs_inode **ipp,
613 struct xfs_inode *ip;
615 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino);
618 ip = xfs_inode_alloc(mp, ino);
622 error = xfs_imap(pag, tp, ip->i_ino, &ip->i_imap, flags);
627 * For version 5 superblocks, if we are initialising a new inode and we
628 * are not utilising the XFS_FEAT_IKEEP inode cluster mode, we can
629 * simply build the new inode core with a random generation number.
631 * For version 4 (and older) superblocks, log recovery is dependent on
632 * the i_flushiter field being initialised from the current on-disk
633 * value and hence we must also read the inode off disk even when
634 * initializing new inodes.
636 if (xfs_has_v3inodes(mp) &&
637 (flags & XFS_IGET_CREATE) && !xfs_has_ikeep(mp)) {
638 VFS_I(ip)->i_generation = get_random_u32();
642 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp);
646 error = xfs_inode_from_disk(ip,
647 xfs_buf_offset(bp, ip->i_imap.im_boffset));
649 xfs_buf_set_ref(bp, XFS_INO_REF);
651 xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
652 xfs_trans_brelse(tp, bp);
658 trace_xfs_iget_miss(ip);
661 * Check the inode free state is valid. This also detects lookup
662 * racing with unlinks.
664 error = xfs_iget_check_free_state(ip, flags);
669 * Preload the radix tree so we can insert safely under the
670 * write spinlock. Note that we cannot sleep inside the preload
673 if (radix_tree_preload(GFP_KERNEL | __GFP_NOLOCKDEP)) {
679 * Because the inode hasn't been added to the radix-tree yet it can't
680 * be found by another thread, so we can do the non-sleeping lock here.
683 if (!xfs_ilock_nowait(ip, lock_flags))
688 * These values must be set before inserting the inode into the radix
689 * tree as the moment it is inserted a concurrent lookup (allowed by the
690 * RCU locking mechanism) can find it and that lookup must see that this
691 * is an inode currently under construction (i.e. that XFS_INEW is set).
692 * The ip->i_flags_lock that protects the XFS_INEW flag forms the
693 * memory barrier that ensures this detection works correctly at lookup
697 if (flags & XFS_IGET_DONTCACHE)
698 d_mark_dontcache(VFS_I(ip));
702 xfs_iflags_set(ip, iflags);
704 /* insert the new inode */
705 spin_lock(&pag->pag_ici_lock);
706 error = radix_tree_insert(&pag->pag_ici_root, agino, ip);
707 if (unlikely(error)) {
708 WARN_ON(error != -EEXIST);
709 XFS_STATS_INC(mp, xs_ig_dup);
711 goto out_preload_end;
713 spin_unlock(&pag->pag_ici_lock);
714 radix_tree_preload_end();
720 spin_unlock(&pag->pag_ici_lock);
721 radix_tree_preload_end();
723 xfs_iunlock(ip, lock_flags);
725 __destroy_inode(VFS_I(ip));
731 * Look up an inode by number in the given file system. The inode is looked up
732 * in the cache held in each AG. If the inode is found in the cache, initialise
733 * the vfs inode if necessary.
735 * If it is not in core, read it in from the file system's device, add it to the
736 * cache and initialise the vfs inode.
738 * The inode is locked according to the value of the lock_flags parameter.
739 * Inode lookup is only done during metadata operations and not as part of the
740 * data IO path. Hence we only allow locking of the XFS_ILOCK during lookup.
744 struct xfs_mount *mp,
745 struct xfs_trans *tp,
749 struct xfs_inode **ipp)
751 struct xfs_inode *ip;
752 struct xfs_perag *pag;
756 ASSERT((lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) == 0);
758 /* reject inode numbers outside existing AGs */
759 if (!ino || XFS_INO_TO_AGNO(mp, ino) >= mp->m_sb.sb_agcount)
762 XFS_STATS_INC(mp, xs_ig_attempts);
764 /* get the perag structure and ensure that it's inode capable */
765 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
766 agino = XFS_INO_TO_AGINO(mp, ino);
771 ip = radix_tree_lookup(&pag->pag_ici_root, agino);
774 error = xfs_iget_cache_hit(pag, ip, ino, flags, lock_flags);
776 goto out_error_or_again;
779 if (flags & XFS_IGET_INCORE) {
781 goto out_error_or_again;
783 XFS_STATS_INC(mp, xs_ig_missed);
785 error = xfs_iget_cache_miss(mp, pag, tp, ino, &ip,
788 goto out_error_or_again;
795 * If we have a real type for an on-disk inode, we can setup the inode
796 * now. If it's a new inode being created, xfs_init_new_inode will
799 if (xfs_iflags_test(ip, XFS_INEW) && VFS_I(ip)->i_mode != 0)
800 xfs_setup_existing_inode(ip);
804 if (!(flags & (XFS_IGET_INCORE | XFS_IGET_NORETRY)) &&
814 * Grab the inode for reclaim exclusively.
816 * We have found this inode via a lookup under RCU, so the inode may have
817 * already been freed, or it may be in the process of being recycled by
818 * xfs_iget(). In both cases, the inode will have XFS_IRECLAIM set. If the inode
819 * has been fully recycled by the time we get the i_flags_lock, XFS_IRECLAIMABLE
820 * will not be set. Hence we need to check for both these flag conditions to
821 * avoid inodes that are no longer reclaim candidates.
823 * Note: checking for other state flags here, under the i_flags_lock or not, is
824 * racy and should be avoided. Those races should be resolved only after we have
825 * ensured that we are able to reclaim this inode and the world can see that we
826 * are going to reclaim it.
828 * Return true if we grabbed it, false otherwise.
832 struct xfs_inode *ip,
833 struct xfs_icwalk *icw)
835 ASSERT(rcu_read_lock_held());
837 spin_lock(&ip->i_flags_lock);
838 if (!__xfs_iflags_test(ip, XFS_IRECLAIMABLE) ||
839 __xfs_iflags_test(ip, XFS_IRECLAIM)) {
840 /* not a reclaim candidate. */
841 spin_unlock(&ip->i_flags_lock);
845 /* Don't reclaim a sick inode unless the caller asked for it. */
847 (!icw || !(icw->icw_flags & XFS_ICWALK_FLAG_RECLAIM_SICK))) {
848 spin_unlock(&ip->i_flags_lock);
852 __xfs_iflags_set(ip, XFS_IRECLAIM);
853 spin_unlock(&ip->i_flags_lock);
858 * Inode reclaim is non-blocking, so the default action if progress cannot be
859 * made is to "requeue" the inode for reclaim by unlocking it and clearing the
860 * XFS_IRECLAIM flag. If we are in a shutdown state, we don't care about
861 * blocking anymore and hence we can wait for the inode to be able to reclaim
864 * We do no IO here - if callers require inodes to be cleaned they must push the
865 * AIL first to trigger writeback of dirty inodes. This enables writeback to be
866 * done in the background in a non-blocking manner, and enables memory reclaim
867 * to make progress without blocking.
871 struct xfs_inode *ip,
872 struct xfs_perag *pag)
874 xfs_ino_t ino = ip->i_ino; /* for radix_tree_delete */
876 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
878 if (xfs_iflags_test_and_set(ip, XFS_IFLUSHING))
882 * Check for log shutdown because aborting the inode can move the log
883 * tail and corrupt in memory state. This is fine if the log is shut
884 * down, but if the log is still active and only the mount is shut down
885 * then the in-memory log tail movement caused by the abort can be
886 * incorrectly propagated to disk.
888 if (xlog_is_shutdown(ip->i_mount->m_log)) {
890 xfs_iflush_shutdown_abort(ip);
893 if (xfs_ipincount(ip))
894 goto out_clear_flush;
895 if (!xfs_inode_clean(ip))
896 goto out_clear_flush;
898 xfs_iflags_clear(ip, XFS_IFLUSHING);
900 trace_xfs_inode_reclaiming(ip);
903 * Because we use RCU freeing we need to ensure the inode always appears
904 * to be reclaimed with an invalid inode number when in the free state.
905 * We do this as early as possible under the ILOCK so that
906 * xfs_iflush_cluster() and xfs_ifree_cluster() can be guaranteed to
907 * detect races with us here. By doing this, we guarantee that once
908 * xfs_iflush_cluster() or xfs_ifree_cluster() has locked XFS_ILOCK that
909 * it will see either a valid inode that will serialise correctly, or it
910 * will see an invalid inode that it can skip.
912 spin_lock(&ip->i_flags_lock);
913 ip->i_flags = XFS_IRECLAIM;
917 spin_unlock(&ip->i_flags_lock);
919 ASSERT(!ip->i_itemp || ip->i_itemp->ili_item.li_buf == NULL);
920 xfs_iunlock(ip, XFS_ILOCK_EXCL);
922 XFS_STATS_INC(ip->i_mount, xs_ig_reclaims);
924 * Remove the inode from the per-AG radix tree.
926 * Because radix_tree_delete won't complain even if the item was never
927 * added to the tree assert that it's been there before to catch
928 * problems with the inode life time early on.
930 spin_lock(&pag->pag_ici_lock);
931 if (!radix_tree_delete(&pag->pag_ici_root,
932 XFS_INO_TO_AGINO(ip->i_mount, ino)))
934 xfs_perag_clear_inode_tag(pag, NULLAGINO, XFS_ICI_RECLAIM_TAG);
935 spin_unlock(&pag->pag_ici_lock);
938 * Here we do an (almost) spurious inode lock in order to coordinate
939 * with inode cache radix tree lookups. This is because the lookup
940 * can reference the inodes in the cache without taking references.
942 * We make that OK here by ensuring that we wait until the inode is
943 * unlocked after the lookup before we go ahead and free it.
945 xfs_ilock(ip, XFS_ILOCK_EXCL);
946 ASSERT(!ip->i_udquot && !ip->i_gdquot && !ip->i_pdquot);
947 xfs_iunlock(ip, XFS_ILOCK_EXCL);
948 ASSERT(xfs_inode_clean(ip));
950 __xfs_inode_free(ip);
954 xfs_iflags_clear(ip, XFS_IFLUSHING);
956 xfs_iunlock(ip, XFS_ILOCK_EXCL);
958 xfs_iflags_clear(ip, XFS_IRECLAIM);
961 /* Reclaim sick inodes if we're unmounting or the fs went down. */
963 xfs_want_reclaim_sick(
964 struct xfs_mount *mp)
966 return xfs_is_unmounting(mp) || xfs_has_norecovery(mp) ||
972 struct xfs_mount *mp)
974 struct xfs_icwalk icw = {
978 if (xfs_want_reclaim_sick(mp))
979 icw.icw_flags |= XFS_ICWALK_FLAG_RECLAIM_SICK;
981 while (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_RECLAIM_TAG)) {
982 xfs_ail_push_all_sync(mp->m_ail);
983 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, &icw);
988 * The shrinker infrastructure determines how many inodes we should scan for
989 * reclaim. We want as many clean inodes ready to reclaim as possible, so we
990 * push the AIL here. We also want to proactively free up memory if we can to
991 * minimise the amount of work memory reclaim has to do so we kick the
992 * background reclaim if it isn't already scheduled.
995 xfs_reclaim_inodes_nr(
996 struct xfs_mount *mp,
997 unsigned long nr_to_scan)
999 struct xfs_icwalk icw = {
1000 .icw_flags = XFS_ICWALK_FLAG_SCAN_LIMIT,
1001 .icw_scan_limit = min_t(unsigned long, LONG_MAX, nr_to_scan),
1004 if (xfs_want_reclaim_sick(mp))
1005 icw.icw_flags |= XFS_ICWALK_FLAG_RECLAIM_SICK;
1007 /* kick background reclaimer and push the AIL */
1008 xfs_reclaim_work_queue(mp);
1009 xfs_ail_push_all(mp->m_ail);
1011 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, &icw);
1016 * Return the number of reclaimable inodes in the filesystem for
1017 * the shrinker to determine how much to reclaim.
1020 xfs_reclaim_inodes_count(
1021 struct xfs_mount *mp)
1023 struct xfs_perag *pag;
1024 xfs_agnumber_t ag = 0;
1025 long reclaimable = 0;
1027 while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) {
1028 ag = pag->pag_agno + 1;
1029 reclaimable += pag->pag_ici_reclaimable;
1036 xfs_icwalk_match_id(
1037 struct xfs_inode *ip,
1038 struct xfs_icwalk *icw)
1040 if ((icw->icw_flags & XFS_ICWALK_FLAG_UID) &&
1041 !uid_eq(VFS_I(ip)->i_uid, icw->icw_uid))
1044 if ((icw->icw_flags & XFS_ICWALK_FLAG_GID) &&
1045 !gid_eq(VFS_I(ip)->i_gid, icw->icw_gid))
1048 if ((icw->icw_flags & XFS_ICWALK_FLAG_PRID) &&
1049 ip->i_projid != icw->icw_prid)
1056 * A union-based inode filtering algorithm. Process the inode if any of the
1057 * criteria match. This is for global/internal scans only.
1060 xfs_icwalk_match_id_union(
1061 struct xfs_inode *ip,
1062 struct xfs_icwalk *icw)
1064 if ((icw->icw_flags & XFS_ICWALK_FLAG_UID) &&
1065 uid_eq(VFS_I(ip)->i_uid, icw->icw_uid))
1068 if ((icw->icw_flags & XFS_ICWALK_FLAG_GID) &&
1069 gid_eq(VFS_I(ip)->i_gid, icw->icw_gid))
1072 if ((icw->icw_flags & XFS_ICWALK_FLAG_PRID) &&
1073 ip->i_projid == icw->icw_prid)
1080 * Is this inode @ip eligible for eof/cow block reclamation, given some
1081 * filtering parameters @icw? The inode is eligible if @icw is null or
1082 * if the predicate functions match.
1086 struct xfs_inode *ip,
1087 struct xfs_icwalk *icw)
1094 if (icw->icw_flags & XFS_ICWALK_FLAG_UNION)
1095 match = xfs_icwalk_match_id_union(ip, icw);
1097 match = xfs_icwalk_match_id(ip, icw);
1101 /* skip the inode if the file size is too small */
1102 if ((icw->icw_flags & XFS_ICWALK_FLAG_MINFILESIZE) &&
1103 XFS_ISIZE(ip) < icw->icw_min_file_size)
1110 * This is a fast pass over the inode cache to try to get reclaim moving on as
1111 * many inodes as possible in a short period of time. It kicks itself every few
1112 * seconds, as well as being kicked by the inode cache shrinker when memory
1117 struct work_struct *work)
1119 struct xfs_mount *mp = container_of(to_delayed_work(work),
1120 struct xfs_mount, m_reclaim_work);
1122 xfs_icwalk(mp, XFS_ICWALK_RECLAIM, NULL);
1123 xfs_reclaim_work_queue(mp);
1127 xfs_inode_free_eofblocks(
1128 struct xfs_inode *ip,
1129 struct xfs_icwalk *icw,
1130 unsigned int *lockflags)
1134 wait = icw && (icw->icw_flags & XFS_ICWALK_FLAG_SYNC);
1136 if (!xfs_iflags_test(ip, XFS_IEOFBLOCKS))
1140 * If the mapping is dirty the operation can block and wait for some
1141 * time. Unless we are waiting, skip it.
1143 if (!wait && mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_DIRTY))
1146 if (!xfs_icwalk_match(ip, icw))
1150 * If the caller is waiting, return -EAGAIN to keep the background
1151 * scanner moving and revisit the inode in a subsequent pass.
1153 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1158 *lockflags |= XFS_IOLOCK_EXCL;
1160 if (xfs_can_free_eofblocks(ip, false))
1161 return xfs_free_eofblocks(ip);
1163 /* inode could be preallocated or append-only */
1164 trace_xfs_inode_free_eofblocks_invalid(ip);
1165 xfs_inode_clear_eofblocks_tag(ip);
1170 xfs_blockgc_set_iflag(
1171 struct xfs_inode *ip,
1172 unsigned long iflag)
1174 struct xfs_mount *mp = ip->i_mount;
1175 struct xfs_perag *pag;
1177 ASSERT((iflag & ~(XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0);
1180 * Don't bother locking the AG and looking up in the radix trees
1181 * if we already know that we have the tag set.
1183 if (ip->i_flags & iflag)
1185 spin_lock(&ip->i_flags_lock);
1186 ip->i_flags |= iflag;
1187 spin_unlock(&ip->i_flags_lock);
1189 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1190 spin_lock(&pag->pag_ici_lock);
1192 xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1193 XFS_ICI_BLOCKGC_TAG);
1195 spin_unlock(&pag->pag_ici_lock);
1200 xfs_inode_set_eofblocks_tag(
1203 trace_xfs_inode_set_eofblocks_tag(ip);
1204 return xfs_blockgc_set_iflag(ip, XFS_IEOFBLOCKS);
1208 xfs_blockgc_clear_iflag(
1209 struct xfs_inode *ip,
1210 unsigned long iflag)
1212 struct xfs_mount *mp = ip->i_mount;
1213 struct xfs_perag *pag;
1216 ASSERT((iflag & ~(XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0);
1218 spin_lock(&ip->i_flags_lock);
1219 ip->i_flags &= ~iflag;
1220 clear_tag = (ip->i_flags & (XFS_IEOFBLOCKS | XFS_ICOWBLOCKS)) == 0;
1221 spin_unlock(&ip->i_flags_lock);
1226 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1227 spin_lock(&pag->pag_ici_lock);
1229 xfs_perag_clear_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1230 XFS_ICI_BLOCKGC_TAG);
1232 spin_unlock(&pag->pag_ici_lock);
1237 xfs_inode_clear_eofblocks_tag(
1240 trace_xfs_inode_clear_eofblocks_tag(ip);
1241 return xfs_blockgc_clear_iflag(ip, XFS_IEOFBLOCKS);
1245 * Set ourselves up to free CoW blocks from this file. If it's already clean
1246 * then we can bail out quickly, but otherwise we must back off if the file
1247 * is undergoing some kind of write.
1250 xfs_prep_free_cowblocks(
1251 struct xfs_inode *ip)
1254 * Just clear the tag if we have an empty cow fork or none at all. It's
1255 * possible the inode was fully unshared since it was originally tagged.
1257 if (!xfs_inode_has_cow_data(ip)) {
1258 trace_xfs_inode_free_cowblocks_invalid(ip);
1259 xfs_inode_clear_cowblocks_tag(ip);
1264 * If the mapping is dirty or under writeback we cannot touch the
1265 * CoW fork. Leave it alone if we're in the midst of a directio.
1267 if ((VFS_I(ip)->i_state & I_DIRTY_PAGES) ||
1268 mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_DIRTY) ||
1269 mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_WRITEBACK) ||
1270 atomic_read(&VFS_I(ip)->i_dio_count))
1277 * Automatic CoW Reservation Freeing
1279 * These functions automatically garbage collect leftover CoW reservations
1280 * that were made on behalf of a cowextsize hint when we start to run out
1281 * of quota or when the reservations sit around for too long. If the file
1282 * has dirty pages or is undergoing writeback, its CoW reservations will
1285 * The actual garbage collection piggybacks off the same code that runs
1286 * the speculative EOF preallocation garbage collector.
1289 xfs_inode_free_cowblocks(
1290 struct xfs_inode *ip,
1291 struct xfs_icwalk *icw,
1292 unsigned int *lockflags)
1297 wait = icw && (icw->icw_flags & XFS_ICWALK_FLAG_SYNC);
1299 if (!xfs_iflags_test(ip, XFS_ICOWBLOCKS))
1302 if (!xfs_prep_free_cowblocks(ip))
1305 if (!xfs_icwalk_match(ip, icw))
1309 * If the caller is waiting, return -EAGAIN to keep the background
1310 * scanner moving and revisit the inode in a subsequent pass.
1312 if (!(*lockflags & XFS_IOLOCK_EXCL) &&
1313 !xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1318 *lockflags |= XFS_IOLOCK_EXCL;
1320 if (!xfs_ilock_nowait(ip, XFS_MMAPLOCK_EXCL)) {
1325 *lockflags |= XFS_MMAPLOCK_EXCL;
1328 * Check again, nobody else should be able to dirty blocks or change
1329 * the reflink iflag now that we have the first two locks held.
1331 if (xfs_prep_free_cowblocks(ip))
1332 ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
1337 xfs_inode_set_cowblocks_tag(
1340 trace_xfs_inode_set_cowblocks_tag(ip);
1341 return xfs_blockgc_set_iflag(ip, XFS_ICOWBLOCKS);
1345 xfs_inode_clear_cowblocks_tag(
1348 trace_xfs_inode_clear_cowblocks_tag(ip);
1349 return xfs_blockgc_clear_iflag(ip, XFS_ICOWBLOCKS);
1352 /* Disable post-EOF and CoW block auto-reclamation. */
1355 struct xfs_mount *mp)
1357 struct xfs_perag *pag;
1358 xfs_agnumber_t agno;
1360 if (!xfs_clear_blockgc_enabled(mp))
1363 for_each_perag(mp, agno, pag)
1364 cancel_delayed_work_sync(&pag->pag_blockgc_work);
1365 trace_xfs_blockgc_stop(mp, __return_address);
1368 /* Enable post-EOF and CoW block auto-reclamation. */
1371 struct xfs_mount *mp)
1373 struct xfs_perag *pag;
1374 xfs_agnumber_t agno;
1376 if (xfs_set_blockgc_enabled(mp))
1379 trace_xfs_blockgc_start(mp, __return_address);
1380 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1381 xfs_blockgc_queue(pag);
1384 /* Don't try to run block gc on an inode that's in any of these states. */
1385 #define XFS_BLOCKGC_NOGRAB_IFLAGS (XFS_INEW | \
1386 XFS_NEED_INACTIVE | \
1387 XFS_INACTIVATING | \
1388 XFS_IRECLAIMABLE | \
1391 * Decide if the given @ip is eligible for garbage collection of speculative
1392 * preallocations, and grab it if so. Returns true if it's ready to go or
1393 * false if we should just ignore it.
1397 struct xfs_inode *ip)
1399 struct inode *inode = VFS_I(ip);
1401 ASSERT(rcu_read_lock_held());
1403 /* Check for stale RCU freed inode */
1404 spin_lock(&ip->i_flags_lock);
1406 goto out_unlock_noent;
1408 if (ip->i_flags & XFS_BLOCKGC_NOGRAB_IFLAGS)
1409 goto out_unlock_noent;
1410 spin_unlock(&ip->i_flags_lock);
1412 /* nothing to sync during shutdown */
1413 if (xfs_is_shutdown(ip->i_mount))
1416 /* If we can't grab the inode, it must on it's way to reclaim. */
1420 /* inode is valid */
1424 spin_unlock(&ip->i_flags_lock);
1428 /* Scan one incore inode for block preallocations that we can remove. */
1430 xfs_blockgc_scan_inode(
1431 struct xfs_inode *ip,
1432 struct xfs_icwalk *icw)
1434 unsigned int lockflags = 0;
1437 error = xfs_inode_free_eofblocks(ip, icw, &lockflags);
1441 error = xfs_inode_free_cowblocks(ip, icw, &lockflags);
1444 xfs_iunlock(ip, lockflags);
1449 /* Background worker that trims preallocated space. */
1452 struct work_struct *work)
1454 struct xfs_perag *pag = container_of(to_delayed_work(work),
1455 struct xfs_perag, pag_blockgc_work);
1456 struct xfs_mount *mp = pag->pag_mount;
1459 trace_xfs_blockgc_worker(mp, __return_address);
1461 error = xfs_icwalk_ag(pag, XFS_ICWALK_BLOCKGC, NULL);
1463 xfs_info(mp, "AG %u preallocation gc worker failed, err=%d",
1464 pag->pag_agno, error);
1465 xfs_blockgc_queue(pag);
1469 * Try to free space in the filesystem by purging inactive inodes, eofblocks
1473 xfs_blockgc_free_space(
1474 struct xfs_mount *mp,
1475 struct xfs_icwalk *icw)
1479 trace_xfs_blockgc_free_space(mp, icw, _RET_IP_);
1481 error = xfs_icwalk(mp, XFS_ICWALK_BLOCKGC, icw);
1485 return xfs_inodegc_flush(mp);
1489 * Reclaim all the free space that we can by scheduling the background blockgc
1490 * and inodegc workers immediately and waiting for them all to clear.
1493 xfs_blockgc_flush_all(
1494 struct xfs_mount *mp)
1496 struct xfs_perag *pag;
1497 xfs_agnumber_t agno;
1499 trace_xfs_blockgc_flush_all(mp, __return_address);
1502 * For each blockgc worker, move its queue time up to now. If it
1503 * wasn't queued, it will not be requeued. Then flush whatever's
1506 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1507 mod_delayed_work(pag->pag_mount->m_blockgc_wq,
1508 &pag->pag_blockgc_work, 0);
1510 for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
1511 flush_delayed_work(&pag->pag_blockgc_work);
1513 return xfs_inodegc_flush(mp);
1517 * Run cow/eofblocks scans on the supplied dquots. We don't know exactly which
1518 * quota caused an allocation failure, so we make a best effort by including
1519 * each quota under low free space conditions (less than 1% free space) in the
1522 * Callers must not hold any inode's ILOCK. If requesting a synchronous scan
1523 * (XFS_ICWALK_FLAG_SYNC), the caller also must not hold any inode's IOLOCK or
1527 xfs_blockgc_free_dquots(
1528 struct xfs_mount *mp,
1529 struct xfs_dquot *udqp,
1530 struct xfs_dquot *gdqp,
1531 struct xfs_dquot *pdqp,
1532 unsigned int iwalk_flags)
1534 struct xfs_icwalk icw = {0};
1535 bool do_work = false;
1537 if (!udqp && !gdqp && !pdqp)
1541 * Run a scan to free blocks using the union filter to cover all
1542 * applicable quotas in a single scan.
1544 icw.icw_flags = XFS_ICWALK_FLAG_UNION | iwalk_flags;
1546 if (XFS_IS_UQUOTA_ENFORCED(mp) && udqp && xfs_dquot_lowsp(udqp)) {
1547 icw.icw_uid = make_kuid(mp->m_super->s_user_ns, udqp->q_id);
1548 icw.icw_flags |= XFS_ICWALK_FLAG_UID;
1552 if (XFS_IS_UQUOTA_ENFORCED(mp) && gdqp && xfs_dquot_lowsp(gdqp)) {
1553 icw.icw_gid = make_kgid(mp->m_super->s_user_ns, gdqp->q_id);
1554 icw.icw_flags |= XFS_ICWALK_FLAG_GID;
1558 if (XFS_IS_PQUOTA_ENFORCED(mp) && pdqp && xfs_dquot_lowsp(pdqp)) {
1559 icw.icw_prid = pdqp->q_id;
1560 icw.icw_flags |= XFS_ICWALK_FLAG_PRID;
1567 return xfs_blockgc_free_space(mp, &icw);
1570 /* Run cow/eofblocks scans on the quotas attached to the inode. */
1572 xfs_blockgc_free_quota(
1573 struct xfs_inode *ip,
1574 unsigned int iwalk_flags)
1576 return xfs_blockgc_free_dquots(ip->i_mount,
1577 xfs_inode_dquot(ip, XFS_DQTYPE_USER),
1578 xfs_inode_dquot(ip, XFS_DQTYPE_GROUP),
1579 xfs_inode_dquot(ip, XFS_DQTYPE_PROJ), iwalk_flags);
1582 /* XFS Inode Cache Walking Code */
1585 * The inode lookup is done in batches to keep the amount of lock traffic and
1586 * radix tree lookups to a minimum. The batch size is a trade off between
1587 * lookup reduction and stack usage. This is in the reclaim path, so we can't
1590 #define XFS_LOOKUP_BATCH 32
1594 * Decide if we want to grab this inode in anticipation of doing work towards
1599 enum xfs_icwalk_goal goal,
1600 struct xfs_inode *ip,
1601 struct xfs_icwalk *icw)
1604 case XFS_ICWALK_BLOCKGC:
1605 return xfs_blockgc_igrab(ip);
1606 case XFS_ICWALK_RECLAIM:
1607 return xfs_reclaim_igrab(ip, icw);
1614 * Process an inode. Each processing function must handle any state changes
1615 * made by the icwalk igrab function. Return -EAGAIN to skip an inode.
1618 xfs_icwalk_process_inode(
1619 enum xfs_icwalk_goal goal,
1620 struct xfs_inode *ip,
1621 struct xfs_perag *pag,
1622 struct xfs_icwalk *icw)
1627 case XFS_ICWALK_BLOCKGC:
1628 error = xfs_blockgc_scan_inode(ip, icw);
1630 case XFS_ICWALK_RECLAIM:
1631 xfs_reclaim_inode(ip, pag);
1638 * For a given per-AG structure @pag and a goal, grab qualifying inodes and
1639 * process them in some manner.
1643 struct xfs_perag *pag,
1644 enum xfs_icwalk_goal goal,
1645 struct xfs_icwalk *icw)
1647 struct xfs_mount *mp = pag->pag_mount;
1648 uint32_t first_index;
1657 if (goal == XFS_ICWALK_RECLAIM)
1658 first_index = READ_ONCE(pag->pag_ici_reclaim_cursor);
1663 struct xfs_inode *batch[XFS_LOOKUP_BATCH];
1669 nr_found = radix_tree_gang_lookup_tag(&pag->pag_ici_root,
1670 (void **) batch, first_index,
1671 XFS_LOOKUP_BATCH, goal);
1679 * Grab the inodes before we drop the lock. if we found
1680 * nothing, nr == 0 and the loop will be skipped.
1682 for (i = 0; i < nr_found; i++) {
1683 struct xfs_inode *ip = batch[i];
1685 if (done || !xfs_icwalk_igrab(goal, ip, icw))
1689 * Update the index for the next lookup. Catch
1690 * overflows into the next AG range which can occur if
1691 * we have inodes in the last block of the AG and we
1692 * are currently pointing to the last inode.
1694 * Because we may see inodes that are from the wrong AG
1695 * due to RCU freeing and reallocation, only update the
1696 * index if it lies in this AG. It was a race that lead
1697 * us to see this inode, so another lookup from the
1698 * same index will not find it again.
1700 if (XFS_INO_TO_AGNO(mp, ip->i_ino) != pag->pag_agno)
1702 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
1703 if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino))
1707 /* unlock now we've grabbed the inodes. */
1710 for (i = 0; i < nr_found; i++) {
1713 error = xfs_icwalk_process_inode(goal, batch[i], pag,
1715 if (error == -EAGAIN) {
1719 if (error && last_error != -EFSCORRUPTED)
1723 /* bail out if the filesystem is corrupted. */
1724 if (error == -EFSCORRUPTED)
1729 if (icw && (icw->icw_flags & XFS_ICWALK_FLAG_SCAN_LIMIT)) {
1730 icw->icw_scan_limit -= XFS_LOOKUP_BATCH;
1731 if (icw->icw_scan_limit <= 0)
1734 } while (nr_found && !done);
1736 if (goal == XFS_ICWALK_RECLAIM) {
1739 WRITE_ONCE(pag->pag_ici_reclaim_cursor, first_index);
1749 /* Walk all incore inodes to achieve a given goal. */
1752 struct xfs_mount *mp,
1753 enum xfs_icwalk_goal goal,
1754 struct xfs_icwalk *icw)
1756 struct xfs_perag *pag;
1759 xfs_agnumber_t agno;
1761 for_each_perag_tag(mp, agno, pag, goal) {
1762 error = xfs_icwalk_ag(pag, goal, icw);
1765 if (error == -EFSCORRUPTED) {
1766 xfs_perag_rele(pag);
1772 BUILD_BUG_ON(XFS_ICWALK_PRIVATE_FLAGS & XFS_ICWALK_FLAGS_VALID);
1778 struct xfs_inode *ip,
1781 struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork);
1782 struct xfs_bmbt_irec got;
1783 struct xfs_iext_cursor icur;
1785 if (!ifp || !xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got))
1788 if (isnullstartblock(got.br_startblock)) {
1789 xfs_warn(ip->i_mount,
1790 "ino %llx %s fork has delalloc extent at [0x%llx:0x%llx]",
1792 whichfork == XFS_DATA_FORK ? "data" : "cow",
1793 got.br_startoff, got.br_blockcount);
1795 } while (xfs_iext_next_extent(ifp, &icur, &got));
1798 #define xfs_check_delalloc(ip, whichfork) do { } while (0)
1801 /* Schedule the inode for reclaim. */
1803 xfs_inodegc_set_reclaimable(
1804 struct xfs_inode *ip)
1806 struct xfs_mount *mp = ip->i_mount;
1807 struct xfs_perag *pag;
1809 if (!xfs_is_shutdown(mp) && ip->i_delayed_blks) {
1810 xfs_check_delalloc(ip, XFS_DATA_FORK);
1811 xfs_check_delalloc(ip, XFS_COW_FORK);
1815 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1816 spin_lock(&pag->pag_ici_lock);
1817 spin_lock(&ip->i_flags_lock);
1819 trace_xfs_inode_set_reclaimable(ip);
1820 ip->i_flags &= ~(XFS_NEED_INACTIVE | XFS_INACTIVATING);
1821 ip->i_flags |= XFS_IRECLAIMABLE;
1822 xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
1823 XFS_ICI_RECLAIM_TAG);
1825 spin_unlock(&ip->i_flags_lock);
1826 spin_unlock(&pag->pag_ici_lock);
1831 * Free all speculative preallocations and possibly even the inode itself.
1832 * This is the last chance to make changes to an otherwise unreferenced file
1833 * before incore reclamation happens.
1836 xfs_inodegc_inactivate(
1837 struct xfs_inode *ip)
1841 trace_xfs_inode_inactivating(ip);
1842 error = xfs_inactive(ip);
1843 xfs_inodegc_set_reclaimable(ip);
1850 struct work_struct *work)
1852 struct xfs_inodegc *gc = container_of(to_delayed_work(work),
1853 struct xfs_inodegc, work);
1854 struct llist_node *node = llist_del_all(&gc->list);
1855 struct xfs_inode *ip, *n;
1856 struct xfs_mount *mp = gc->mp;
1857 unsigned int nofs_flag;
1860 * Clear the cpu mask bit and ensure that we have seen the latest
1861 * update of the gc structure associated with this CPU. This matches
1862 * with the release semantics used when setting the cpumask bit in
1863 * xfs_inodegc_queue.
1865 cpumask_clear_cpu(gc->cpu, &mp->m_inodegc_cpumask);
1866 smp_mb__after_atomic();
1868 WRITE_ONCE(gc->items, 0);
1874 * We can allocate memory here while doing writeback on behalf of
1875 * memory reclaim. To avoid memory allocation deadlocks set the
1876 * task-wide nofs context for the following operations.
1878 nofs_flag = memalloc_nofs_save();
1880 ip = llist_entry(node, struct xfs_inode, i_gclist);
1881 trace_xfs_inodegc_worker(mp, READ_ONCE(gc->shrinker_hits));
1883 WRITE_ONCE(gc->shrinker_hits, 0);
1884 llist_for_each_entry_safe(ip, n, node, i_gclist) {
1887 xfs_iflags_set(ip, XFS_INACTIVATING);
1888 error = xfs_inodegc_inactivate(ip);
1889 if (error && !gc->error)
1893 memalloc_nofs_restore(nofs_flag);
1897 * Expedite all pending inodegc work to run immediately. This does not wait for
1898 * completion of the work.
1902 struct xfs_mount *mp)
1904 if (!xfs_is_inodegc_enabled(mp))
1906 trace_xfs_inodegc_push(mp, __return_address);
1907 xfs_inodegc_queue_all(mp);
1911 * Force all currently queued inode inactivation work to run immediately and
1912 * wait for the work to finish.
1916 struct xfs_mount *mp)
1918 xfs_inodegc_push(mp);
1919 trace_xfs_inodegc_flush(mp, __return_address);
1920 return xfs_inodegc_wait_all(mp);
1924 * Flush all the pending work and then disable the inode inactivation background
1925 * workers and wait for them to stop. Caller must hold sb->s_umount to
1926 * coordinate changes in the inodegc_enabled state.
1930 struct xfs_mount *mp)
1934 if (!xfs_clear_inodegc_enabled(mp))
1938 * Drain all pending inodegc work, including inodes that could be
1939 * queued by racing xfs_inodegc_queue or xfs_inodegc_shrinker_scan
1940 * threads that sample the inodegc state just prior to us clearing it.
1941 * The inodegc flag state prevents new threads from queuing more
1942 * inodes, so we queue pending work items and flush the workqueue until
1943 * all inodegc lists are empty. IOWs, we cannot use drain_workqueue
1944 * here because it does not allow other unserialized mechanisms to
1945 * reschedule inodegc work while this draining is in progress.
1947 xfs_inodegc_queue_all(mp);
1949 flush_workqueue(mp->m_inodegc_wq);
1950 rerun = xfs_inodegc_queue_all(mp);
1953 trace_xfs_inodegc_stop(mp, __return_address);
1957 * Enable the inode inactivation background workers and schedule deferred inode
1958 * inactivation work if there is any. Caller must hold sb->s_umount to
1959 * coordinate changes in the inodegc_enabled state.
1963 struct xfs_mount *mp)
1965 if (xfs_set_inodegc_enabled(mp))
1968 trace_xfs_inodegc_start(mp, __return_address);
1969 xfs_inodegc_queue_all(mp);
1972 #ifdef CONFIG_XFS_RT
1974 xfs_inodegc_want_queue_rt_file(
1975 struct xfs_inode *ip)
1977 struct xfs_mount *mp = ip->i_mount;
1979 if (!XFS_IS_REALTIME_INODE(ip))
1982 if (__percpu_counter_compare(&mp->m_frextents,
1983 mp->m_low_rtexts[XFS_LOWSP_5_PCNT],
1984 XFS_FDBLOCKS_BATCH) < 0)
1990 # define xfs_inodegc_want_queue_rt_file(ip) (false)
1991 #endif /* CONFIG_XFS_RT */
1994 * Schedule the inactivation worker when:
1996 * - We've accumulated more than one inode cluster buffer's worth of inodes.
1997 * - There is less than 5% free space left.
1998 * - Any of the quotas for this inode are near an enforcement limit.
2001 xfs_inodegc_want_queue_work(
2002 struct xfs_inode *ip,
2005 struct xfs_mount *mp = ip->i_mount;
2007 if (items > mp->m_ino_geo.inodes_per_cluster)
2010 if (__percpu_counter_compare(&mp->m_fdblocks,
2011 mp->m_low_space[XFS_LOWSP_5_PCNT],
2012 XFS_FDBLOCKS_BATCH) < 0)
2015 if (xfs_inodegc_want_queue_rt_file(ip))
2018 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_USER))
2021 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_GROUP))
2024 if (xfs_inode_near_dquot_enforcement(ip, XFS_DQTYPE_PROJ))
2031 * Upper bound on the number of inodes in each AG that can be queued for
2032 * inactivation at any given time, to avoid monopolizing the workqueue.
2034 #define XFS_INODEGC_MAX_BACKLOG (4 * XFS_INODES_PER_CHUNK)
2037 * Make the frontend wait for inactivations when:
2039 * - Memory shrinkers queued the inactivation worker and it hasn't finished.
2040 * - The queue depth exceeds the maximum allowable percpu backlog.
2042 * Note: If we are in a NOFS context here (e.g. current thread is running a
2043 * transaction) the we don't want to block here as inodegc progress may require
2044 * filesystem resources we hold to make progress and that could result in a
2045 * deadlock. Hence we skip out of here if we are in a scoped NOFS context.
2048 xfs_inodegc_want_flush_work(
2049 struct xfs_inode *ip,
2051 unsigned int shrinker_hits)
2053 if (current->flags & PF_MEMALLOC_NOFS)
2056 if (shrinker_hits > 0)
2059 if (items > XFS_INODEGC_MAX_BACKLOG)
2066 * Queue a background inactivation worker if there are inodes that need to be
2067 * inactivated and higher level xfs code hasn't disabled the background
2072 struct xfs_inode *ip)
2074 struct xfs_mount *mp = ip->i_mount;
2075 struct xfs_inodegc *gc;
2077 unsigned int shrinker_hits;
2078 unsigned int cpu_nr;
2079 unsigned long queue_delay = 1;
2081 trace_xfs_inode_set_need_inactive(ip);
2082 spin_lock(&ip->i_flags_lock);
2083 ip->i_flags |= XFS_NEED_INACTIVE;
2084 spin_unlock(&ip->i_flags_lock);
2087 gc = this_cpu_ptr(mp->m_inodegc);
2088 llist_add(&ip->i_gclist, &gc->list);
2089 items = READ_ONCE(gc->items);
2090 WRITE_ONCE(gc->items, items + 1);
2091 shrinker_hits = READ_ONCE(gc->shrinker_hits);
2094 * Ensure the list add is always seen by anyone who finds the cpumask
2095 * bit set. This effectively gives the cpumask bit set operation
2096 * release ordering semantics.
2098 smp_mb__before_atomic();
2099 if (!cpumask_test_cpu(cpu_nr, &mp->m_inodegc_cpumask))
2100 cpumask_test_and_set_cpu(cpu_nr, &mp->m_inodegc_cpumask);
2103 * We queue the work while holding the current CPU so that the work
2104 * is scheduled to run on this CPU.
2106 if (!xfs_is_inodegc_enabled(mp)) {
2111 if (xfs_inodegc_want_queue_work(ip, items))
2114 trace_xfs_inodegc_queue(mp, __return_address);
2115 mod_delayed_work_on(current_cpu(), mp->m_inodegc_wq, &gc->work,
2119 if (xfs_inodegc_want_flush_work(ip, items, shrinker_hits)) {
2120 trace_xfs_inodegc_throttle(mp, __return_address);
2121 flush_delayed_work(&gc->work);
2126 * We set the inode flag atomically with the radix tree tag. Once we get tag
2127 * lookups on the radix tree, this inode flag can go away.
2129 * We always use background reclaim here because even if the inode is clean, it
2130 * still may be under IO and hence we have wait for IO completion to occur
2131 * before we can reclaim the inode. The background reclaim path handles this
2132 * more efficiently than we can here, so simply let background reclaim tear down
2136 xfs_inode_mark_reclaimable(
2137 struct xfs_inode *ip)
2139 struct xfs_mount *mp = ip->i_mount;
2142 XFS_STATS_INC(mp, vn_reclaim);
2145 * We should never get here with any of the reclaim flags already set.
2147 ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_ALL_IRECLAIM_FLAGS));
2149 need_inactive = xfs_inode_needs_inactive(ip);
2150 if (need_inactive) {
2151 xfs_inodegc_queue(ip);
2155 /* Going straight to reclaim, so drop the dquots. */
2156 xfs_qm_dqdetach(ip);
2157 xfs_inodegc_set_reclaimable(ip);
2161 * Register a phony shrinker so that we can run background inodegc sooner when
2162 * there's memory pressure. Inactivation does not itself free any memory but
2163 * it does make inodes reclaimable, which eventually frees memory.
2165 * The count function, seek value, and batch value are crafted to trigger the
2166 * scan function during the second round of scanning. Hopefully this means
2167 * that we reclaimed enough memory that initiating metadata transactions won't
2168 * make things worse.
2170 #define XFS_INODEGC_SHRINKER_COUNT (1UL << DEF_PRIORITY)
2171 #define XFS_INODEGC_SHRINKER_BATCH ((XFS_INODEGC_SHRINKER_COUNT / 2) + 1)
2173 static unsigned long
2174 xfs_inodegc_shrinker_count(
2175 struct shrinker *shrink,
2176 struct shrink_control *sc)
2178 struct xfs_mount *mp = shrink->private_data;
2179 struct xfs_inodegc *gc;
2182 if (!xfs_is_inodegc_enabled(mp))
2185 for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
2186 gc = per_cpu_ptr(mp->m_inodegc, cpu);
2187 if (!llist_empty(&gc->list))
2188 return XFS_INODEGC_SHRINKER_COUNT;
2194 static unsigned long
2195 xfs_inodegc_shrinker_scan(
2196 struct shrinker *shrink,
2197 struct shrink_control *sc)
2199 struct xfs_mount *mp = shrink->private_data;
2200 struct xfs_inodegc *gc;
2202 bool no_items = true;
2204 if (!xfs_is_inodegc_enabled(mp))
2207 trace_xfs_inodegc_shrinker_scan(mp, sc, __return_address);
2209 for_each_cpu(cpu, &mp->m_inodegc_cpumask) {
2210 gc = per_cpu_ptr(mp->m_inodegc, cpu);
2211 if (!llist_empty(&gc->list)) {
2212 unsigned int h = READ_ONCE(gc->shrinker_hits);
2214 WRITE_ONCE(gc->shrinker_hits, h + 1);
2215 mod_delayed_work_on(cpu, mp->m_inodegc_wq, &gc->work, 0);
2221 * If there are no inodes to inactivate, we don't want the shrinker
2222 * to think there's deferred work to call us back about.
2230 /* Register a shrinker so we can accelerate inodegc and throttle queuing. */
2232 xfs_inodegc_register_shrinker(
2233 struct xfs_mount *mp)
2235 mp->m_inodegc_shrinker = shrinker_alloc(SHRINKER_NONSLAB,
2238 if (!mp->m_inodegc_shrinker)
2241 mp->m_inodegc_shrinker->count_objects = xfs_inodegc_shrinker_count;
2242 mp->m_inodegc_shrinker->scan_objects = xfs_inodegc_shrinker_scan;
2243 mp->m_inodegc_shrinker->seeks = 0;
2244 mp->m_inodegc_shrinker->batch = XFS_INODEGC_SHRINKER_BATCH;
2245 mp->m_inodegc_shrinker->private_data = mp;
2247 shrinker_register(mp->m_inodegc_shrinker);