1 // SPDX-License-Identifier: GPL-2.0
4 * fs/ext4/fast_commit.c
6 * Written by Harshad Shirwadkar <harshadshirwadkar@gmail.com>
8 * Ext4 fast commits routines.
11 #include "ext4_jbd2.h"
12 #include "ext4_extents.h"
19 * Ext4 fast commits implement fine grained journalling for Ext4.
21 * Fast commits are organized as a log of tag-length-value (TLV) structs. (See
22 * struct ext4_fc_tl). Each TLV contains some delta that is replayed TLV by
23 * TLV during the recovery phase. For the scenarios for which we currently
24 * don't have replay code, fast commit falls back to full commits.
25 * Fast commits record delta in one of the following three categories.
27 * (A) Directory entry updates:
29 * - EXT4_FC_TAG_UNLINK - records directory entry unlink
30 * - EXT4_FC_TAG_LINK - records directory entry link
31 * - EXT4_FC_TAG_CREAT - records inode and directory entry creation
33 * (B) File specific data range updates:
35 * - EXT4_FC_TAG_ADD_RANGE - records addition of new blocks to an inode
36 * - EXT4_FC_TAG_DEL_RANGE - records deletion of blocks from an inode
38 * (C) Inode metadata (mtime / ctime etc):
40 * - EXT4_FC_TAG_INODE - record the inode that should be replayed
41 * during recovery. Note that iblocks field is
42 * not replayed and instead derived during
46 * With fast commits, we maintain all the directory entry operations in the
47 * order in which they are issued in an in-memory queue. This queue is flushed
48 * to disk during the commit operation. We also maintain a list of inodes
49 * that need to be committed during a fast commit in another in memory queue of
50 * inodes. During the commit operation, we commit in the following order:
52 * [1] Lock inodes for any further data updates by setting COMMITTING state
53 * [2] Submit data buffers of all the inodes
54 * [3] Wait for [2] to complete
55 * [4] Commit all the directory entry updates in the fast commit space
56 * [5] Commit all the changed inode structures
57 * [6] Write tail tag (this tag ensures the atomicity, please read the following
58 * section for more details).
59 * [7] Wait for [4], [5] and [6] to complete.
61 * All the inode updates must call ext4_fc_start_update() before starting an
62 * update. If such an ongoing update is present, fast commit waits for it to
63 * complete. The completion of such an update is marked by
64 * ext4_fc_stop_update().
66 * Fast Commit Ineligibility
67 * -------------------------
68 * Not all operations are supported by fast commits today (e.g extended
69 * attributes). Fast commit ineligiblity is marked by calling one of the
70 * two following functions:
72 * - ext4_fc_mark_ineligible(): This makes next fast commit operation to fall
73 * back to full commit. This is useful in case of transient errors.
75 * - ext4_fc_start_ineligible() and ext4_fc_stop_ineligible() - This makes all
76 * the fast commits happening between ext4_fc_start_ineligible() and
77 * ext4_fc_stop_ineligible() and one fast commit after the call to
78 * ext4_fc_stop_ineligible() to fall back to full commits. It is important to
79 * make one more fast commit to fall back to full commit after stop call so
80 * that it guaranteed that the fast commit ineligible operation contained
81 * within ext4_fc_start_ineligible() and ext4_fc_stop_ineligible() is
82 * followed by at least 1 full commit.
84 * Atomicity of commits
85 * --------------------
86 * In order to guarantee atomicity during the commit operation, fast commit
87 * uses "EXT4_FC_TAG_TAIL" tag that marks a fast commit as complete. Tail
88 * tag contains CRC of the contents and TID of the transaction after which
89 * this fast commit should be applied. Recovery code replays fast commit
90 * logs only if there's at least 1 valid tail present. For every fast commit
91 * operation, there is 1 tail. This means, we may end up with multiple tails
92 * in the fast commit space. Here's an example:
94 * - Create a new file A and remove existing file B
96 * - Append contents to file A
100 * The fast commit space at the end of above operations would look like this:
101 * [HEAD] [CREAT A] [UNLINK B] [TAIL] [ADD_RANGE A] [DEL_RANGE A] [TAIL]
102 * |<--- Fast Commit 1 --->|<--- Fast Commit 2 ---->|
104 * Replay code should thus check for all the valid tails in the FC area.
106 * Fast Commit Replay Idempotence
107 * ------------------------------
109 * Fast commits tags are idempotent in nature provided the recovery code follows
110 * certain rules. The guiding principle that the commit path follows while
111 * committing is that it stores the result of a particular operation instead of
112 * storing the procedure.
114 * Let's consider this rename operation: 'mv /a /b'. Let's assume dirent '/a'
115 * was associated with inode 10. During fast commit, instead of storing this
116 * operation as a procedure "rename a to b", we store the resulting file system
117 * state as a "series" of outcomes:
119 * - Link dirent b to inode 10
121 * - Inode <10> with valid refcount
123 * Now when recovery code runs, it needs "enforce" this state on the file
124 * system. This is what guarantees idempotence of fast commit replay.
126 * Let's take an example of a procedure that is not idempotent and see how fast
127 * commits make it idempotent. Consider following sequence of operations:
129 * rm A; mv B A; read A
132 * (x), (y) and (z) are the points at which we can crash. If we store this
133 * sequence of operations as is then the replay is not idempotent. Let's say
134 * while in replay, we crash at (z). During the second replay, file A (which was
135 * actually created as a result of "mv B A" operation) would get deleted. Thus,
136 * file named A would be absent when we try to read A. So, this sequence of
137 * operations is not idempotent. However, as mentioned above, instead of storing
138 * the procedure fast commits store the outcome of each procedure. Thus the fast
139 * commit log for above procedure would be as follows:
141 * (Let's assume dirent A was linked to inode 10 and dirent B was linked to
142 * inode 11 before the replay)
144 * [Unlink A] [Link A to inode 11] [Unlink B] [Inode 11]
147 * If we crash at (z), we will have file A linked to inode 11. During the second
148 * replay, we will remove file A (inode 11). But we will create it back and make
149 * it point to inode 11. We won't find B, so we'll just skip that step. At this
150 * point, the refcount for inode 11 is not reliable, but that gets fixed by the
151 * replay of last inode 11 tag. Crashes at points (w), (x) and (y) get handled
152 * similarly. Thus, by converting a non-idempotent procedure into a series of
153 * idempotent outcomes, fast commits ensured idempotence during the replay.
158 * 0) Fast commit replay path hardening: Fast commit replay code should use
159 * journal handles to make sure all the updates it does during the replay
160 * path are atomic. With that if we crash during fast commit replay, after
161 * trying to do recovery again, we will find a file system where fast commit
162 * area is invalid (because new full commit would be found). In order to deal
163 * with that, fast commit replay code should ensure that the "FC_REPLAY"
164 * superblock state is persisted before starting the replay, so that after
165 * the crash, fast commit recovery code can look at that flag and perform
166 * fast commit recovery even if that area is invalidated by later full
169 * 1) Make fast commit atomic updates more fine grained. Today, a fast commit
170 * eligible update must be protected within ext4_fc_start_update() and
171 * ext4_fc_stop_update(). These routines are called at much higher
172 * routines. This can be made more fine grained by combining with
173 * ext4_journal_start().
175 * 2) Same above for ext4_fc_start_ineligible() and ext4_fc_stop_ineligible()
177 * 3) Handle more ineligible cases.
180 #include <trace/events/ext4.h>
181 static struct kmem_cache *ext4_fc_dentry_cachep;
183 static void ext4_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
185 BUFFER_TRACE(bh, "");
187 ext4_debug("%s: Block %lld up-to-date",
188 __func__, bh->b_blocknr);
189 set_buffer_uptodate(bh);
191 ext4_debug("%s: Block %lld not up-to-date",
192 __func__, bh->b_blocknr);
193 clear_buffer_uptodate(bh);
199 static inline void ext4_fc_reset_inode(struct inode *inode)
201 struct ext4_inode_info *ei = EXT4_I(inode);
203 ei->i_fc_lblk_start = 0;
204 ei->i_fc_lblk_len = 0;
207 void ext4_fc_init_inode(struct inode *inode)
209 struct ext4_inode_info *ei = EXT4_I(inode);
211 ext4_fc_reset_inode(inode);
212 ext4_clear_inode_state(inode, EXT4_STATE_FC_COMMITTING);
213 INIT_LIST_HEAD(&ei->i_fc_list);
214 init_waitqueue_head(&ei->i_fc_wait);
215 atomic_set(&ei->i_fc_updates, 0);
218 /* This function must be called with sbi->s_fc_lock held. */
219 static void ext4_fc_wait_committing_inode(struct inode *inode)
220 __releases(&EXT4_SB(inode->i_sb)->s_fc_lock)
222 wait_queue_head_t *wq;
223 struct ext4_inode_info *ei = EXT4_I(inode);
225 #if (BITS_PER_LONG < 64)
226 DEFINE_WAIT_BIT(wait, &ei->i_state_flags,
227 EXT4_STATE_FC_COMMITTING);
228 wq = bit_waitqueue(&ei->i_state_flags,
229 EXT4_STATE_FC_COMMITTING);
231 DEFINE_WAIT_BIT(wait, &ei->i_flags,
232 EXT4_STATE_FC_COMMITTING);
233 wq = bit_waitqueue(&ei->i_flags,
234 EXT4_STATE_FC_COMMITTING);
236 lockdep_assert_held(&EXT4_SB(inode->i_sb)->s_fc_lock);
237 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
238 spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
240 finish_wait(wq, &wait.wq_entry);
244 * Inform Ext4's fast about start of an inode update
246 * This function is called by the high level call VFS callbacks before
247 * performing any inode update. This function blocks if there's an ongoing
248 * fast commit on the inode in question.
250 void ext4_fc_start_update(struct inode *inode)
252 struct ext4_inode_info *ei = EXT4_I(inode);
254 if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
255 (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
259 spin_lock(&EXT4_SB(inode->i_sb)->s_fc_lock);
260 if (list_empty(&ei->i_fc_list))
263 if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) {
264 ext4_fc_wait_committing_inode(inode);
268 atomic_inc(&ei->i_fc_updates);
269 spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
273 * Stop inode update and wake up waiting fast commits if any.
275 void ext4_fc_stop_update(struct inode *inode)
277 struct ext4_inode_info *ei = EXT4_I(inode);
279 if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
280 (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
283 if (atomic_dec_and_test(&ei->i_fc_updates))
284 wake_up_all(&ei->i_fc_wait);
288 * Remove inode from fast commit list. If the inode is being committed
289 * we wait until inode commit is done.
291 void ext4_fc_del(struct inode *inode)
293 struct ext4_inode_info *ei = EXT4_I(inode);
295 if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
296 (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
300 spin_lock(&EXT4_SB(inode->i_sb)->s_fc_lock);
301 if (list_empty(&ei->i_fc_list)) {
302 spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
306 if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) {
307 ext4_fc_wait_committing_inode(inode);
310 list_del_init(&ei->i_fc_list);
311 spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
315 * Mark file system as fast commit ineligible. This means that next commit
316 * operation would result in a full jbd2 commit.
318 void ext4_fc_mark_ineligible(struct super_block *sb, int reason)
320 struct ext4_sb_info *sbi = EXT4_SB(sb);
322 if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
323 (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
326 ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
327 WARN_ON(reason >= EXT4_FC_REASON_MAX);
328 sbi->s_fc_stats.fc_ineligible_reason_count[reason]++;
332 * Start a fast commit ineligible update. Any commits that happen while
333 * such an operation is in progress fall back to full commits.
335 void ext4_fc_start_ineligible(struct super_block *sb, int reason)
337 struct ext4_sb_info *sbi = EXT4_SB(sb);
339 if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
340 (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
343 WARN_ON(reason >= EXT4_FC_REASON_MAX);
344 sbi->s_fc_stats.fc_ineligible_reason_count[reason]++;
345 atomic_inc(&sbi->s_fc_ineligible_updates);
349 * Stop a fast commit ineligible update. We set EXT4_MF_FC_INELIGIBLE flag here
350 * to ensure that after stopping the ineligible update, at least one full
351 * commit takes place.
353 void ext4_fc_stop_ineligible(struct super_block *sb)
355 if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
356 (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
359 ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
360 atomic_dec(&EXT4_SB(sb)->s_fc_ineligible_updates);
363 static inline int ext4_fc_is_ineligible(struct super_block *sb)
365 return (ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE) ||
366 atomic_read(&EXT4_SB(sb)->s_fc_ineligible_updates));
370 * Generic fast commit tracking function. If this is the first time this we are
371 * called after a full commit, we initialize fast commit fields and then call
372 * __fc_track_fn() with update = 0. If we have already been called after a full
373 * commit, we pass update = 1. Based on that, the track function can determine
374 * if it needs to track a field for the first time or if it needs to just
375 * update the previously tracked value.
377 * If enqueue is set, this function enqueues the inode in fast commit list.
379 static int ext4_fc_track_template(
380 handle_t *handle, struct inode *inode,
381 int (*__fc_track_fn)(struct inode *, void *, bool),
382 void *args, int enqueue)
385 struct ext4_inode_info *ei = EXT4_I(inode);
386 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
390 if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
391 (sbi->s_mount_state & EXT4_FC_REPLAY))
394 if (ext4_fc_is_ineligible(inode->i_sb))
397 tid = handle->h_transaction->t_tid;
398 mutex_lock(&ei->i_fc_lock);
399 if (tid == ei->i_sync_tid) {
402 ext4_fc_reset_inode(inode);
403 ei->i_sync_tid = tid;
405 ret = __fc_track_fn(inode, args, update);
406 mutex_unlock(&ei->i_fc_lock);
411 spin_lock(&sbi->s_fc_lock);
412 if (list_empty(&EXT4_I(inode)->i_fc_list))
413 list_add_tail(&EXT4_I(inode)->i_fc_list,
414 (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_COMMITTING)) ?
415 &sbi->s_fc_q[FC_Q_STAGING] :
416 &sbi->s_fc_q[FC_Q_MAIN]);
417 spin_unlock(&sbi->s_fc_lock);
422 struct __track_dentry_update_args {
423 struct dentry *dentry;
427 /* __track_fn for directory entry updates. Called with ei->i_fc_lock. */
428 static int __track_dentry_update(struct inode *inode, void *arg, bool update)
430 struct ext4_fc_dentry_update *node;
431 struct ext4_inode_info *ei = EXT4_I(inode);
432 struct __track_dentry_update_args *dentry_update =
433 (struct __track_dentry_update_args *)arg;
434 struct dentry *dentry = dentry_update->dentry;
435 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
437 mutex_unlock(&ei->i_fc_lock);
438 node = kmem_cache_alloc(ext4_fc_dentry_cachep, GFP_NOFS);
440 ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_NOMEM);
441 mutex_lock(&ei->i_fc_lock);
445 node->fcd_op = dentry_update->op;
446 node->fcd_parent = dentry->d_parent->d_inode->i_ino;
447 node->fcd_ino = inode->i_ino;
448 if (dentry->d_name.len > DNAME_INLINE_LEN) {
449 node->fcd_name.name = kmalloc(dentry->d_name.len, GFP_NOFS);
450 if (!node->fcd_name.name) {
451 kmem_cache_free(ext4_fc_dentry_cachep, node);
452 ext4_fc_mark_ineligible(inode->i_sb,
453 EXT4_FC_REASON_NOMEM);
454 mutex_lock(&ei->i_fc_lock);
457 memcpy((u8 *)node->fcd_name.name, dentry->d_name.name,
460 memcpy(node->fcd_iname, dentry->d_name.name,
462 node->fcd_name.name = node->fcd_iname;
464 node->fcd_name.len = dentry->d_name.len;
466 spin_lock(&sbi->s_fc_lock);
467 if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_COMMITTING))
468 list_add_tail(&node->fcd_list,
469 &sbi->s_fc_dentry_q[FC_Q_STAGING]);
471 list_add_tail(&node->fcd_list, &sbi->s_fc_dentry_q[FC_Q_MAIN]);
472 spin_unlock(&sbi->s_fc_lock);
473 mutex_lock(&ei->i_fc_lock);
478 void __ext4_fc_track_unlink(handle_t *handle,
479 struct inode *inode, struct dentry *dentry)
481 struct __track_dentry_update_args args;
484 args.dentry = dentry;
485 args.op = EXT4_FC_TAG_UNLINK;
487 ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
489 trace_ext4_fc_track_unlink(inode, dentry, ret);
492 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry)
494 __ext4_fc_track_unlink(handle, d_inode(dentry), dentry);
497 void __ext4_fc_track_link(handle_t *handle,
498 struct inode *inode, struct dentry *dentry)
500 struct __track_dentry_update_args args;
503 args.dentry = dentry;
504 args.op = EXT4_FC_TAG_LINK;
506 ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
508 trace_ext4_fc_track_link(inode, dentry, ret);
511 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry)
513 __ext4_fc_track_link(handle, d_inode(dentry), dentry);
516 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry)
518 struct __track_dentry_update_args args;
519 struct inode *inode = d_inode(dentry);
522 args.dentry = dentry;
523 args.op = EXT4_FC_TAG_CREAT;
525 ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
527 trace_ext4_fc_track_create(inode, dentry, ret);
530 /* __track_fn for inode tracking */
531 static int __track_inode(struct inode *inode, void *arg, bool update)
536 EXT4_I(inode)->i_fc_lblk_len = 0;
541 void ext4_fc_track_inode(handle_t *handle, struct inode *inode)
545 if (S_ISDIR(inode->i_mode))
548 if (ext4_should_journal_data(inode)) {
549 ext4_fc_mark_ineligible(inode->i_sb,
550 EXT4_FC_REASON_INODE_JOURNAL_DATA);
554 ret = ext4_fc_track_template(handle, inode, __track_inode, NULL, 1);
555 trace_ext4_fc_track_inode(inode, ret);
558 struct __track_range_args {
559 ext4_lblk_t start, end;
562 /* __track_fn for tracking data updates */
563 static int __track_range(struct inode *inode, void *arg, bool update)
565 struct ext4_inode_info *ei = EXT4_I(inode);
566 ext4_lblk_t oldstart;
567 struct __track_range_args *__arg =
568 (struct __track_range_args *)arg;
570 if (inode->i_ino < EXT4_FIRST_INO(inode->i_sb)) {
571 ext4_debug("Special inode %ld being modified\n", inode->i_ino);
575 oldstart = ei->i_fc_lblk_start;
577 if (update && ei->i_fc_lblk_len > 0) {
578 ei->i_fc_lblk_start = min(ei->i_fc_lblk_start, __arg->start);
580 max(oldstart + ei->i_fc_lblk_len - 1, __arg->end) -
581 ei->i_fc_lblk_start + 1;
583 ei->i_fc_lblk_start = __arg->start;
584 ei->i_fc_lblk_len = __arg->end - __arg->start + 1;
590 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
593 struct __track_range_args args;
596 if (S_ISDIR(inode->i_mode))
602 ret = ext4_fc_track_template(handle, inode, __track_range, &args, 1);
604 trace_ext4_fc_track_range(inode, start, end, ret);
607 static void ext4_fc_submit_bh(struct super_block *sb, bool is_tail)
609 int write_flags = REQ_SYNC;
610 struct buffer_head *bh = EXT4_SB(sb)->s_fc_bh;
612 /* Add REQ_FUA | REQ_PREFLUSH only its tail */
613 if (test_opt(sb, BARRIER) && is_tail)
614 write_flags |= REQ_FUA | REQ_PREFLUSH;
616 set_buffer_dirty(bh);
617 set_buffer_uptodate(bh);
618 bh->b_end_io = ext4_end_buffer_io_sync;
619 submit_bh(REQ_OP_WRITE, write_flags, bh);
620 EXT4_SB(sb)->s_fc_bh = NULL;
623 /* Ext4 commit path routines */
625 /* memzero and update CRC */
626 static void *ext4_fc_memzero(struct super_block *sb, void *dst, int len,
631 ret = memset(dst, 0, len);
633 *crc = ext4_chksum(EXT4_SB(sb), *crc, dst, len);
638 * Allocate len bytes on a fast commit buffer.
640 * During the commit time this function is used to manage fast commit
641 * block space. We don't split a fast commit log onto different
642 * blocks. So this function makes sure that if there's not enough space
643 * on the current block, the remaining space in the current block is
644 * marked as unused by adding EXT4_FC_TAG_PAD tag. In that case,
645 * new block is from jbd2 and CRC is updated to reflect the padding
648 static u8 *ext4_fc_reserve_space(struct super_block *sb, int len, u32 *crc)
650 struct ext4_fc_tl *tl;
651 struct ext4_sb_info *sbi = EXT4_SB(sb);
652 struct buffer_head *bh;
653 int bsize = sbi->s_journal->j_blocksize;
654 int ret, off = sbi->s_fc_bytes % bsize;
658 * After allocating len, we should have space at least for a 0 byte
661 if (len + sizeof(struct ext4_fc_tl) > bsize)
664 if (bsize - off - 1 > len + sizeof(struct ext4_fc_tl)) {
666 * Only allocate from current buffer if we have enough space for
667 * this request AND we have space to add a zero byte padding.
670 ret = jbd2_fc_get_buf(EXT4_SB(sb)->s_journal, &bh);
675 sbi->s_fc_bytes += len;
676 return sbi->s_fc_bh->b_data + off;
678 /* Need to add PAD tag */
679 tl = (struct ext4_fc_tl *)(sbi->s_fc_bh->b_data + off);
680 tl->fc_tag = cpu_to_le16(EXT4_FC_TAG_PAD);
681 pad_len = bsize - off - 1 - sizeof(struct ext4_fc_tl);
682 tl->fc_len = cpu_to_le16(pad_len);
684 *crc = ext4_chksum(sbi, *crc, tl, sizeof(*tl));
686 ext4_fc_memzero(sb, tl + 1, pad_len, crc);
687 ext4_fc_submit_bh(sb, false);
689 ret = jbd2_fc_get_buf(EXT4_SB(sb)->s_journal, &bh);
693 sbi->s_fc_bytes = (sbi->s_fc_bytes / bsize + 1) * bsize + len;
694 return sbi->s_fc_bh->b_data;
697 /* memcpy to fc reserved space and update CRC */
698 static void *ext4_fc_memcpy(struct super_block *sb, void *dst, const void *src,
702 *crc = ext4_chksum(EXT4_SB(sb), *crc, src, len);
703 return memcpy(dst, src, len);
707 * Complete a fast commit by writing tail tag.
709 * Writing tail tag marks the end of a fast commit. In order to guarantee
710 * atomicity, after writing tail tag, even if there's space remaining
711 * in the block, next commit shouldn't use it. That's why tail tag
712 * has the length as that of the remaining space on the block.
714 static int ext4_fc_write_tail(struct super_block *sb, u32 crc)
716 struct ext4_sb_info *sbi = EXT4_SB(sb);
717 struct ext4_fc_tl tl;
718 struct ext4_fc_tail tail;
719 int off, bsize = sbi->s_journal->j_blocksize;
723 * ext4_fc_reserve_space takes care of allocating an extra block if
724 * there's no enough space on this block for accommodating this tail.
726 dst = ext4_fc_reserve_space(sb, sizeof(tl) + sizeof(tail), &crc);
730 off = sbi->s_fc_bytes % bsize;
732 tl.fc_tag = cpu_to_le16(EXT4_FC_TAG_TAIL);
733 tl.fc_len = cpu_to_le16(bsize - off - 1 + sizeof(struct ext4_fc_tail));
734 sbi->s_fc_bytes = round_up(sbi->s_fc_bytes, bsize);
736 ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), &crc);
738 tail.fc_tid = cpu_to_le32(sbi->s_journal->j_running_transaction->t_tid);
739 ext4_fc_memcpy(sb, dst, &tail.fc_tid, sizeof(tail.fc_tid), &crc);
740 dst += sizeof(tail.fc_tid);
741 tail.fc_crc = cpu_to_le32(crc);
742 ext4_fc_memcpy(sb, dst, &tail.fc_crc, sizeof(tail.fc_crc), NULL);
744 ext4_fc_submit_bh(sb, true);
750 * Adds tag, length, value and updates CRC. Returns true if tlv was added.
751 * Returns false if there's not enough space.
753 static bool ext4_fc_add_tlv(struct super_block *sb, u16 tag, u16 len, u8 *val,
756 struct ext4_fc_tl tl;
759 dst = ext4_fc_reserve_space(sb, sizeof(tl) + len, crc);
763 tl.fc_tag = cpu_to_le16(tag);
764 tl.fc_len = cpu_to_le16(len);
766 ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), crc);
767 ext4_fc_memcpy(sb, dst + sizeof(tl), val, len, crc);
772 /* Same as above, but adds dentry tlv. */
773 static bool ext4_fc_add_dentry_tlv(struct super_block *sb, u16 tag,
774 int parent_ino, int ino, int dlen,
775 const unsigned char *dname,
778 struct ext4_fc_dentry_info fcd;
779 struct ext4_fc_tl tl;
780 u8 *dst = ext4_fc_reserve_space(sb, sizeof(tl) + sizeof(fcd) + dlen,
786 fcd.fc_parent_ino = cpu_to_le32(parent_ino);
787 fcd.fc_ino = cpu_to_le32(ino);
788 tl.fc_tag = cpu_to_le16(tag);
789 tl.fc_len = cpu_to_le16(sizeof(fcd) + dlen);
790 ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), crc);
792 ext4_fc_memcpy(sb, dst, &fcd, sizeof(fcd), crc);
794 ext4_fc_memcpy(sb, dst, dname, dlen, crc);
801 * Writes inode in the fast commit space under TLV with tag @tag.
802 * Returns 0 on success, error on failure.
804 static int ext4_fc_write_inode(struct inode *inode, u32 *crc)
806 struct ext4_inode_info *ei = EXT4_I(inode);
807 int inode_len = EXT4_GOOD_OLD_INODE_SIZE;
809 struct ext4_iloc iloc;
810 struct ext4_fc_inode fc_inode;
811 struct ext4_fc_tl tl;
814 ret = ext4_get_inode_loc(inode, &iloc);
818 if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE)
819 inode_len += ei->i_extra_isize;
821 fc_inode.fc_ino = cpu_to_le32(inode->i_ino);
822 tl.fc_tag = cpu_to_le16(EXT4_FC_TAG_INODE);
823 tl.fc_len = cpu_to_le16(inode_len + sizeof(fc_inode.fc_ino));
825 dst = ext4_fc_reserve_space(inode->i_sb,
826 sizeof(tl) + inode_len + sizeof(fc_inode.fc_ino), crc);
830 if (!ext4_fc_memcpy(inode->i_sb, dst, &tl, sizeof(tl), crc))
833 if (!ext4_fc_memcpy(inode->i_sb, dst, &fc_inode, sizeof(fc_inode), crc))
835 dst += sizeof(fc_inode);
836 if (!ext4_fc_memcpy(inode->i_sb, dst, (u8 *)ext4_raw_inode(&iloc),
844 * Writes updated data ranges for the inode in question. Updates CRC.
845 * Returns 0 on success, error otherwise.
847 static int ext4_fc_write_inode_data(struct inode *inode, u32 *crc)
849 ext4_lblk_t old_blk_size, cur_lblk_off, new_blk_size;
850 struct ext4_inode_info *ei = EXT4_I(inode);
851 struct ext4_map_blocks map;
852 struct ext4_fc_add_range fc_ext;
853 struct ext4_fc_del_range lrange;
854 struct ext4_extent *ex;
857 mutex_lock(&ei->i_fc_lock);
858 if (ei->i_fc_lblk_len == 0) {
859 mutex_unlock(&ei->i_fc_lock);
862 old_blk_size = ei->i_fc_lblk_start;
863 new_blk_size = ei->i_fc_lblk_start + ei->i_fc_lblk_len - 1;
864 ei->i_fc_lblk_len = 0;
865 mutex_unlock(&ei->i_fc_lock);
867 cur_lblk_off = old_blk_size;
868 jbd_debug(1, "%s: will try writing %d to %d for inode %ld\n",
869 __func__, cur_lblk_off, new_blk_size, inode->i_ino);
871 while (cur_lblk_off <= new_blk_size) {
872 map.m_lblk = cur_lblk_off;
873 map.m_len = new_blk_size - cur_lblk_off + 1;
874 ret = ext4_map_blocks(NULL, inode, &map, 0);
878 if (map.m_len == 0) {
884 lrange.fc_ino = cpu_to_le32(inode->i_ino);
885 lrange.fc_lblk = cpu_to_le32(map.m_lblk);
886 lrange.fc_len = cpu_to_le32(map.m_len);
887 if (!ext4_fc_add_tlv(inode->i_sb, EXT4_FC_TAG_DEL_RANGE,
888 sizeof(lrange), (u8 *)&lrange, crc))
891 fc_ext.fc_ino = cpu_to_le32(inode->i_ino);
892 ex = (struct ext4_extent *)&fc_ext.fc_ex;
893 ex->ee_block = cpu_to_le32(map.m_lblk);
894 ex->ee_len = cpu_to_le16(map.m_len);
895 ext4_ext_store_pblock(ex, map.m_pblk);
896 if (map.m_flags & EXT4_MAP_UNWRITTEN)
897 ext4_ext_mark_unwritten(ex);
899 ext4_ext_mark_initialized(ex);
900 if (!ext4_fc_add_tlv(inode->i_sb, EXT4_FC_TAG_ADD_RANGE,
901 sizeof(fc_ext), (u8 *)&fc_ext, crc))
905 cur_lblk_off += map.m_len;
912 /* Submit data for all the fast commit inodes */
913 static int ext4_fc_submit_inode_data_all(journal_t *journal)
915 struct super_block *sb = (struct super_block *)(journal->j_private);
916 struct ext4_sb_info *sbi = EXT4_SB(sb);
917 struct ext4_inode_info *ei;
920 spin_lock(&sbi->s_fc_lock);
921 ext4_set_mount_flag(sb, EXT4_MF_FC_COMMITTING);
922 list_for_each_entry(ei, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
923 ext4_set_inode_state(&ei->vfs_inode, EXT4_STATE_FC_COMMITTING);
924 while (atomic_read(&ei->i_fc_updates)) {
927 prepare_to_wait(&ei->i_fc_wait, &wait,
928 TASK_UNINTERRUPTIBLE);
929 if (atomic_read(&ei->i_fc_updates)) {
930 spin_unlock(&sbi->s_fc_lock);
932 spin_lock(&sbi->s_fc_lock);
934 finish_wait(&ei->i_fc_wait, &wait);
936 spin_unlock(&sbi->s_fc_lock);
937 ret = jbd2_submit_inode_data(ei->jinode);
940 spin_lock(&sbi->s_fc_lock);
942 spin_unlock(&sbi->s_fc_lock);
947 /* Wait for completion of data for all the fast commit inodes */
948 static int ext4_fc_wait_inode_data_all(journal_t *journal)
950 struct super_block *sb = (struct super_block *)(journal->j_private);
951 struct ext4_sb_info *sbi = EXT4_SB(sb);
952 struct ext4_inode_info *pos, *n;
955 spin_lock(&sbi->s_fc_lock);
956 list_for_each_entry_safe(pos, n, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
957 if (!ext4_test_inode_state(&pos->vfs_inode,
958 EXT4_STATE_FC_COMMITTING))
960 spin_unlock(&sbi->s_fc_lock);
962 ret = jbd2_wait_inode_data(journal, pos->jinode);
965 spin_lock(&sbi->s_fc_lock);
967 spin_unlock(&sbi->s_fc_lock);
972 /* Commit all the directory entry updates */
973 static int ext4_fc_commit_dentry_updates(journal_t *journal, u32 *crc)
974 __acquires(&sbi->s_fc_lock)
975 __releases(&sbi->s_fc_lock)
977 struct super_block *sb = (struct super_block *)(journal->j_private);
978 struct ext4_sb_info *sbi = EXT4_SB(sb);
979 struct ext4_fc_dentry_update *fc_dentry, *fc_dentry_n;
981 struct ext4_inode_info *ei, *ei_n;
984 if (list_empty(&sbi->s_fc_dentry_q[FC_Q_MAIN]))
986 list_for_each_entry_safe(fc_dentry, fc_dentry_n,
987 &sbi->s_fc_dentry_q[FC_Q_MAIN], fcd_list) {
988 if (fc_dentry->fcd_op != EXT4_FC_TAG_CREAT) {
989 spin_unlock(&sbi->s_fc_lock);
990 if (!ext4_fc_add_dentry_tlv(
991 sb, fc_dentry->fcd_op,
992 fc_dentry->fcd_parent, fc_dentry->fcd_ino,
993 fc_dentry->fcd_name.len,
994 fc_dentry->fcd_name.name, crc)) {
998 spin_lock(&sbi->s_fc_lock);
1003 list_for_each_entry_safe(ei, ei_n, &sbi->s_fc_q[FC_Q_MAIN],
1005 if (ei->vfs_inode.i_ino == fc_dentry->fcd_ino) {
1006 inode = &ei->vfs_inode;
1011 * If we don't find inode in our list, then it was deleted,
1012 * in which case, we don't need to record it's create tag.
1016 spin_unlock(&sbi->s_fc_lock);
1019 * We first write the inode and then the create dirent. This
1020 * allows the recovery code to create an unnamed inode first
1021 * and then link it to a directory entry. This allows us
1022 * to use namei.c routines almost as is and simplifies
1023 * the recovery code.
1025 ret = ext4_fc_write_inode(inode, crc);
1029 ret = ext4_fc_write_inode_data(inode, crc);
1033 if (!ext4_fc_add_dentry_tlv(
1034 sb, fc_dentry->fcd_op,
1035 fc_dentry->fcd_parent, fc_dentry->fcd_ino,
1036 fc_dentry->fcd_name.len,
1037 fc_dentry->fcd_name.name, crc)) {
1042 spin_lock(&sbi->s_fc_lock);
1046 spin_lock(&sbi->s_fc_lock);
1050 static int ext4_fc_perform_commit(journal_t *journal)
1052 struct super_block *sb = (struct super_block *)(journal->j_private);
1053 struct ext4_sb_info *sbi = EXT4_SB(sb);
1054 struct ext4_inode_info *iter;
1055 struct ext4_fc_head head;
1056 struct inode *inode;
1057 struct blk_plug plug;
1061 ret = ext4_fc_submit_inode_data_all(journal);
1065 ret = ext4_fc_wait_inode_data_all(journal);
1070 * If file system device is different from journal device, issue a cache
1071 * flush before we start writing fast commit blocks.
1073 if (journal->j_fs_dev != journal->j_dev)
1074 blkdev_issue_flush(journal->j_fs_dev);
1076 blk_start_plug(&plug);
1077 if (sbi->s_fc_bytes == 0) {
1079 * Add a head tag only if this is the first fast commit
1082 head.fc_features = cpu_to_le32(EXT4_FC_SUPPORTED_FEATURES);
1083 head.fc_tid = cpu_to_le32(
1084 sbi->s_journal->j_running_transaction->t_tid);
1085 if (!ext4_fc_add_tlv(sb, EXT4_FC_TAG_HEAD, sizeof(head),
1090 spin_lock(&sbi->s_fc_lock);
1091 ret = ext4_fc_commit_dentry_updates(journal, &crc);
1093 spin_unlock(&sbi->s_fc_lock);
1097 list_for_each_entry(iter, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
1098 inode = &iter->vfs_inode;
1099 if (!ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING))
1102 spin_unlock(&sbi->s_fc_lock);
1103 ret = ext4_fc_write_inode_data(inode, &crc);
1106 ret = ext4_fc_write_inode(inode, &crc);
1109 spin_lock(&sbi->s_fc_lock);
1111 spin_unlock(&sbi->s_fc_lock);
1113 ret = ext4_fc_write_tail(sb, crc);
1116 blk_finish_plug(&plug);
1121 * The main commit entry point. Performs a fast commit for transaction
1122 * commit_tid if needed. If it's not possible to perform a fast commit
1123 * due to various reasons, we fall back to full commit. Returns 0
1124 * on success, error otherwise.
1126 int ext4_fc_commit(journal_t *journal, tid_t commit_tid)
1128 struct super_block *sb = (struct super_block *)(journal->j_private);
1129 struct ext4_sb_info *sbi = EXT4_SB(sb);
1130 int nblks = 0, ret, bsize = journal->j_blocksize;
1131 int subtid = atomic_read(&sbi->s_fc_subtid);
1132 int reason = EXT4_FC_REASON_OK, fc_bufs_before = 0;
1133 ktime_t start_time, commit_time;
1135 trace_ext4_fc_commit_start(sb);
1137 start_time = ktime_get();
1139 if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
1140 (ext4_fc_is_ineligible(sb))) {
1141 reason = EXT4_FC_REASON_INELIGIBLE;
1146 ret = jbd2_fc_begin_commit(journal, commit_tid);
1147 if (ret == -EALREADY) {
1148 /* There was an ongoing commit, check if we need to restart */
1149 if (atomic_read(&sbi->s_fc_subtid) <= subtid &&
1150 commit_tid > journal->j_commit_sequence)
1152 reason = EXT4_FC_REASON_ALREADY_COMMITTED;
1155 sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
1156 reason = EXT4_FC_REASON_FC_START_FAILED;
1160 fc_bufs_before = (sbi->s_fc_bytes + bsize - 1) / bsize;
1161 ret = ext4_fc_perform_commit(journal);
1163 sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
1164 reason = EXT4_FC_REASON_FC_FAILED;
1167 nblks = (sbi->s_fc_bytes + bsize - 1) / bsize - fc_bufs_before;
1168 ret = jbd2_fc_wait_bufs(journal, nblks);
1170 sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
1171 reason = EXT4_FC_REASON_FC_FAILED;
1174 atomic_inc(&sbi->s_fc_subtid);
1175 jbd2_fc_end_commit(journal);
1177 /* Has any ineligible update happened since we started? */
1178 if (reason == EXT4_FC_REASON_OK && ext4_fc_is_ineligible(sb)) {
1179 sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
1180 reason = EXT4_FC_REASON_INELIGIBLE;
1183 spin_lock(&sbi->s_fc_lock);
1184 if (reason != EXT4_FC_REASON_OK &&
1185 reason != EXT4_FC_REASON_ALREADY_COMMITTED) {
1186 sbi->s_fc_stats.fc_ineligible_commits++;
1188 sbi->s_fc_stats.fc_num_commits++;
1189 sbi->s_fc_stats.fc_numblks += nblks;
1191 spin_unlock(&sbi->s_fc_lock);
1192 nblks = (reason == EXT4_FC_REASON_OK) ? nblks : 0;
1193 trace_ext4_fc_commit_stop(sb, nblks, reason);
1194 commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
1196 * weight the commit time higher than the average time so we don't
1197 * react too strongly to vast changes in the commit time
1199 if (likely(sbi->s_fc_avg_commit_time))
1200 sbi->s_fc_avg_commit_time = (commit_time +
1201 sbi->s_fc_avg_commit_time * 3) / 4;
1203 sbi->s_fc_avg_commit_time = commit_time;
1205 "Fast commit ended with blks = %d, reason = %d, subtid - %d",
1206 nblks, reason, subtid);
1207 if (reason == EXT4_FC_REASON_FC_FAILED)
1208 return jbd2_fc_end_commit_fallback(journal);
1209 if (reason == EXT4_FC_REASON_FC_START_FAILED ||
1210 reason == EXT4_FC_REASON_INELIGIBLE)
1211 return jbd2_complete_transaction(journal, commit_tid);
1216 * Fast commit cleanup routine. This is called after every fast commit and
1217 * full commit. full is true if we are called after a full commit.
1219 static void ext4_fc_cleanup(journal_t *journal, int full)
1221 struct super_block *sb = journal->j_private;
1222 struct ext4_sb_info *sbi = EXT4_SB(sb);
1223 struct ext4_inode_info *iter, *iter_n;
1224 struct ext4_fc_dentry_update *fc_dentry;
1226 if (full && sbi->s_fc_bh)
1227 sbi->s_fc_bh = NULL;
1229 jbd2_fc_release_bufs(journal);
1231 spin_lock(&sbi->s_fc_lock);
1232 list_for_each_entry_safe(iter, iter_n, &sbi->s_fc_q[FC_Q_MAIN],
1234 list_del_init(&iter->i_fc_list);
1235 ext4_clear_inode_state(&iter->vfs_inode,
1236 EXT4_STATE_FC_COMMITTING);
1237 ext4_fc_reset_inode(&iter->vfs_inode);
1238 /* Make sure EXT4_STATE_FC_COMMITTING bit is clear */
1240 #if (BITS_PER_LONG < 64)
1241 wake_up_bit(&iter->i_state_flags, EXT4_STATE_FC_COMMITTING);
1243 wake_up_bit(&iter->i_flags, EXT4_STATE_FC_COMMITTING);
1247 while (!list_empty(&sbi->s_fc_dentry_q[FC_Q_MAIN])) {
1248 fc_dentry = list_first_entry(&sbi->s_fc_dentry_q[FC_Q_MAIN],
1249 struct ext4_fc_dentry_update,
1251 list_del_init(&fc_dentry->fcd_list);
1252 spin_unlock(&sbi->s_fc_lock);
1254 if (fc_dentry->fcd_name.name &&
1255 fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
1256 kfree(fc_dentry->fcd_name.name);
1257 kmem_cache_free(ext4_fc_dentry_cachep, fc_dentry);
1258 spin_lock(&sbi->s_fc_lock);
1261 list_splice_init(&sbi->s_fc_dentry_q[FC_Q_STAGING],
1262 &sbi->s_fc_dentry_q[FC_Q_MAIN]);
1263 list_splice_init(&sbi->s_fc_q[FC_Q_STAGING],
1264 &sbi->s_fc_q[FC_Q_MAIN]);
1266 ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
1267 ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
1270 sbi->s_fc_bytes = 0;
1271 spin_unlock(&sbi->s_fc_lock);
1272 trace_ext4_fc_stats(sb);
1275 /* Ext4 Replay Path Routines */
1277 /* Helper struct for dentry replay routines */
1278 struct dentry_info_args {
1279 int parent_ino, dname_len, ino, inode_len;
1283 static inline void tl_to_darg(struct dentry_info_args *darg,
1284 struct ext4_fc_tl *tl)
1286 struct ext4_fc_dentry_info *fcd;
1288 fcd = (struct ext4_fc_dentry_info *)ext4_fc_tag_val(tl);
1290 darg->parent_ino = le32_to_cpu(fcd->fc_parent_ino);
1291 darg->ino = le32_to_cpu(fcd->fc_ino);
1292 darg->dname = fcd->fc_dname;
1293 darg->dname_len = ext4_fc_tag_len(tl) -
1294 sizeof(struct ext4_fc_dentry_info);
1297 /* Unlink replay function */
1298 static int ext4_fc_replay_unlink(struct super_block *sb, struct ext4_fc_tl *tl)
1300 struct inode *inode, *old_parent;
1302 struct dentry_info_args darg;
1305 tl_to_darg(&darg, tl);
1307 trace_ext4_fc_replay(sb, EXT4_FC_TAG_UNLINK, darg.ino,
1308 darg.parent_ino, darg.dname_len);
1310 entry.name = darg.dname;
1311 entry.len = darg.dname_len;
1312 inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
1314 if (IS_ERR(inode)) {
1315 jbd_debug(1, "Inode %d not found", darg.ino);
1319 old_parent = ext4_iget(sb, darg.parent_ino,
1321 if (IS_ERR(old_parent)) {
1322 jbd_debug(1, "Dir with inode %d not found", darg.parent_ino);
1327 ret = __ext4_unlink(NULL, old_parent, &entry, inode);
1328 /* -ENOENT ok coz it might not exist anymore. */
1336 static int ext4_fc_replay_link_internal(struct super_block *sb,
1337 struct dentry_info_args *darg,
1338 struct inode *inode)
1340 struct inode *dir = NULL;
1341 struct dentry *dentry_dir = NULL, *dentry_inode = NULL;
1342 struct qstr qstr_dname = QSTR_INIT(darg->dname, darg->dname_len);
1345 dir = ext4_iget(sb, darg->parent_ino, EXT4_IGET_NORMAL);
1347 jbd_debug(1, "Dir with inode %d not found.", darg->parent_ino);
1352 dentry_dir = d_obtain_alias(dir);
1353 if (IS_ERR(dentry_dir)) {
1354 jbd_debug(1, "Failed to obtain dentry");
1359 dentry_inode = d_alloc(dentry_dir, &qstr_dname);
1360 if (!dentry_inode) {
1361 jbd_debug(1, "Inode dentry not created.");
1366 ret = __ext4_link(dir, inode, dentry_inode);
1368 * It's possible that link already existed since data blocks
1369 * for the dir in question got persisted before we crashed OR
1370 * we replayed this tag and crashed before the entire replay
1373 if (ret && ret != -EEXIST) {
1374 jbd_debug(1, "Failed to link\n");
1387 d_drop(dentry_inode);
1394 /* Link replay function */
1395 static int ext4_fc_replay_link(struct super_block *sb, struct ext4_fc_tl *tl)
1397 struct inode *inode;
1398 struct dentry_info_args darg;
1401 tl_to_darg(&darg, tl);
1402 trace_ext4_fc_replay(sb, EXT4_FC_TAG_LINK, darg.ino,
1403 darg.parent_ino, darg.dname_len);
1405 inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
1406 if (IS_ERR(inode)) {
1407 jbd_debug(1, "Inode not found.");
1411 ret = ext4_fc_replay_link_internal(sb, &darg, inode);
1417 * Record all the modified inodes during replay. We use this later to setup
1418 * block bitmaps correctly.
1420 static int ext4_fc_record_modified_inode(struct super_block *sb, int ino)
1422 struct ext4_fc_replay_state *state;
1425 state = &EXT4_SB(sb)->s_fc_replay_state;
1426 for (i = 0; i < state->fc_modified_inodes_used; i++)
1427 if (state->fc_modified_inodes[i] == ino)
1429 if (state->fc_modified_inodes_used == state->fc_modified_inodes_size) {
1430 state->fc_modified_inodes_size +=
1431 EXT4_FC_REPLAY_REALLOC_INCREMENT;
1432 state->fc_modified_inodes = krealloc(
1433 state->fc_modified_inodes, sizeof(int) *
1434 state->fc_modified_inodes_size,
1436 if (!state->fc_modified_inodes)
1439 state->fc_modified_inodes[state->fc_modified_inodes_used++] = ino;
1444 * Inode replay function
1446 static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl)
1448 struct ext4_fc_inode *fc_inode;
1449 struct ext4_inode *raw_inode;
1450 struct ext4_inode *raw_fc_inode;
1451 struct inode *inode = NULL;
1452 struct ext4_iloc iloc;
1453 int inode_len, ino, ret, tag = le16_to_cpu(tl->fc_tag);
1454 struct ext4_extent_header *eh;
1456 fc_inode = (struct ext4_fc_inode *)ext4_fc_tag_val(tl);
1458 ino = le32_to_cpu(fc_inode->fc_ino);
1459 trace_ext4_fc_replay(sb, tag, ino, 0, 0);
1461 inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
1462 if (!IS_ERR(inode)) {
1463 ext4_ext_clear_bb(inode);
1468 ext4_fc_record_modified_inode(sb, ino);
1470 raw_fc_inode = (struct ext4_inode *)fc_inode->fc_raw_inode;
1471 ret = ext4_get_fc_inode_loc(sb, ino, &iloc);
1475 inode_len = ext4_fc_tag_len(tl) - sizeof(struct ext4_fc_inode);
1476 raw_inode = ext4_raw_inode(&iloc);
1478 memcpy(raw_inode, raw_fc_inode, offsetof(struct ext4_inode, i_block));
1479 memcpy(&raw_inode->i_generation, &raw_fc_inode->i_generation,
1480 inode_len - offsetof(struct ext4_inode, i_generation));
1481 if (le32_to_cpu(raw_inode->i_flags) & EXT4_EXTENTS_FL) {
1482 eh = (struct ext4_extent_header *)(&raw_inode->i_block[0]);
1483 if (eh->eh_magic != EXT4_EXT_MAGIC) {
1484 memset(eh, 0, sizeof(*eh));
1485 eh->eh_magic = EXT4_EXT_MAGIC;
1486 eh->eh_max = cpu_to_le16(
1487 (sizeof(raw_inode->i_block) -
1488 sizeof(struct ext4_extent_header))
1489 / sizeof(struct ext4_extent));
1491 } else if (le32_to_cpu(raw_inode->i_flags) & EXT4_INLINE_DATA_FL) {
1492 memcpy(raw_inode->i_block, raw_fc_inode->i_block,
1493 sizeof(raw_inode->i_block));
1496 /* Immediately update the inode on disk. */
1497 ret = ext4_handle_dirty_metadata(NULL, NULL, iloc.bh);
1500 ret = sync_dirty_buffer(iloc.bh);
1503 ret = ext4_mark_inode_used(sb, ino);
1507 /* Given that we just wrote the inode on disk, this SHOULD succeed. */
1508 inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
1509 if (IS_ERR(inode)) {
1510 jbd_debug(1, "Inode not found.");
1511 return -EFSCORRUPTED;
1515 * Our allocator could have made different decisions than before
1516 * crashing. This should be fixed but until then, we calculate
1517 * the number of blocks the inode.
1519 ext4_ext_replay_set_iblocks(inode);
1521 inode->i_generation = le32_to_cpu(ext4_raw_inode(&iloc)->i_generation);
1522 ext4_reset_inode_seed(inode);
1524 ext4_inode_csum_set(inode, ext4_raw_inode(&iloc), EXT4_I(inode));
1525 ret = ext4_handle_dirty_metadata(NULL, NULL, iloc.bh);
1526 sync_dirty_buffer(iloc.bh);
1531 blkdev_issue_flush(sb->s_bdev);
1537 * Dentry create replay function.
1539 * EXT4_FC_TAG_CREAT is preceded by EXT4_FC_TAG_INODE_FULL. Which means, the
1540 * inode for which we are trying to create a dentry here, should already have
1541 * been replayed before we start here.
1543 static int ext4_fc_replay_create(struct super_block *sb, struct ext4_fc_tl *tl)
1546 struct inode *inode = NULL;
1547 struct inode *dir = NULL;
1548 struct dentry_info_args darg;
1550 tl_to_darg(&darg, tl);
1552 trace_ext4_fc_replay(sb, EXT4_FC_TAG_CREAT, darg.ino,
1553 darg.parent_ino, darg.dname_len);
1555 /* This takes care of update group descriptor and other metadata */
1556 ret = ext4_mark_inode_used(sb, darg.ino);
1560 inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
1561 if (IS_ERR(inode)) {
1562 jbd_debug(1, "inode %d not found.", darg.ino);
1568 if (S_ISDIR(inode->i_mode)) {
1570 * If we are creating a directory, we need to make sure that the
1571 * dot and dot dot dirents are setup properly.
1573 dir = ext4_iget(sb, darg.parent_ino, EXT4_IGET_NORMAL);
1575 jbd_debug(1, "Dir %d not found.", darg.ino);
1578 ret = ext4_init_new_dir(NULL, dir, inode);
1585 ret = ext4_fc_replay_link_internal(sb, &darg, inode);
1588 set_nlink(inode, 1);
1589 ext4_mark_inode_dirty(NULL, inode);
1597 * Record physical disk regions which are in use as per fast commit area. Our
1598 * simple replay phase allocator excludes these regions from allocation.
1600 static int ext4_fc_record_regions(struct super_block *sb, int ino,
1601 ext4_lblk_t lblk, ext4_fsblk_t pblk, int len)
1603 struct ext4_fc_replay_state *state;
1604 struct ext4_fc_alloc_region *region;
1606 state = &EXT4_SB(sb)->s_fc_replay_state;
1607 if (state->fc_regions_used == state->fc_regions_size) {
1608 state->fc_regions_size +=
1609 EXT4_FC_REPLAY_REALLOC_INCREMENT;
1610 state->fc_regions = krealloc(
1612 state->fc_regions_size *
1613 sizeof(struct ext4_fc_alloc_region),
1615 if (!state->fc_regions)
1618 region = &state->fc_regions[state->fc_regions_used++];
1620 region->lblk = lblk;
1621 region->pblk = pblk;
1627 /* Replay add range tag */
1628 static int ext4_fc_replay_add_range(struct super_block *sb,
1629 struct ext4_fc_tl *tl)
1631 struct ext4_fc_add_range *fc_add_ex;
1632 struct ext4_extent newex, *ex;
1633 struct inode *inode;
1634 ext4_lblk_t start, cur;
1636 ext4_fsblk_t start_pblk;
1637 struct ext4_map_blocks map;
1638 struct ext4_ext_path *path = NULL;
1641 fc_add_ex = (struct ext4_fc_add_range *)ext4_fc_tag_val(tl);
1642 ex = (struct ext4_extent *)&fc_add_ex->fc_ex;
1644 trace_ext4_fc_replay(sb, EXT4_FC_TAG_ADD_RANGE,
1645 le32_to_cpu(fc_add_ex->fc_ino), le32_to_cpu(ex->ee_block),
1646 ext4_ext_get_actual_len(ex));
1648 inode = ext4_iget(sb, le32_to_cpu(fc_add_ex->fc_ino),
1650 if (IS_ERR(inode)) {
1651 jbd_debug(1, "Inode not found.");
1655 ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
1657 start = le32_to_cpu(ex->ee_block);
1658 start_pblk = ext4_ext_pblock(ex);
1659 len = ext4_ext_get_actual_len(ex);
1663 jbd_debug(1, "ADD_RANGE, lblk %d, pblk %lld, len %d, unwritten %d, inode %ld\n",
1664 start, start_pblk, len, ext4_ext_is_unwritten(ex),
1667 while (remaining > 0) {
1669 map.m_len = remaining;
1671 ret = ext4_map_blocks(NULL, inode, &map, 0);
1679 /* Range is not mapped */
1680 path = ext4_find_extent(inode, cur, NULL, 0);
1685 memset(&newex, 0, sizeof(newex));
1686 newex.ee_block = cpu_to_le32(cur);
1687 ext4_ext_store_pblock(
1688 &newex, start_pblk + cur - start);
1689 newex.ee_len = cpu_to_le16(map.m_len);
1690 if (ext4_ext_is_unwritten(ex))
1691 ext4_ext_mark_unwritten(&newex);
1692 down_write(&EXT4_I(inode)->i_data_sem);
1693 ret = ext4_ext_insert_extent(
1694 NULL, inode, &path, &newex, 0);
1695 up_write((&EXT4_I(inode)->i_data_sem));
1696 ext4_ext_drop_refs(path);
1705 if (start_pblk + cur - start != map.m_pblk) {
1707 * Logical to physical mapping changed. This can happen
1708 * if this range was removed and then reallocated to
1709 * map to new physical blocks during a fast commit.
1711 ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
1712 ext4_ext_is_unwritten(ex),
1713 start_pblk + cur - start);
1719 * Mark the old blocks as free since they aren't used
1720 * anymore. We maintain an array of all the modified
1721 * inodes. In case these blocks are still used at either
1722 * a different logical range in the same inode or in
1723 * some different inode, we will mark them as allocated
1724 * at the end of the FC replay using our array of
1727 ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0);
1731 /* Range is mapped and needs a state change */
1732 jbd_debug(1, "Converting from %d to %d %lld",
1733 map.m_flags & EXT4_MAP_UNWRITTEN,
1734 ext4_ext_is_unwritten(ex), map.m_pblk);
1735 ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
1736 ext4_ext_is_unwritten(ex), map.m_pblk);
1742 * We may have split the extent tree while toggling the state.
1743 * Try to shrink the extent tree now.
1745 ext4_ext_replay_shrink_inode(inode, start + len);
1748 remaining -= map.m_len;
1750 ext4_ext_replay_shrink_inode(inode, i_size_read(inode) >>
1751 sb->s_blocksize_bits);
1756 /* Replay DEL_RANGE tag */
1758 ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl)
1760 struct inode *inode;
1761 struct ext4_fc_del_range *lrange;
1762 struct ext4_map_blocks map;
1763 ext4_lblk_t cur, remaining;
1766 lrange = (struct ext4_fc_del_range *)ext4_fc_tag_val(tl);
1767 cur = le32_to_cpu(lrange->fc_lblk);
1768 remaining = le32_to_cpu(lrange->fc_len);
1770 trace_ext4_fc_replay(sb, EXT4_FC_TAG_DEL_RANGE,
1771 le32_to_cpu(lrange->fc_ino), cur, remaining);
1773 inode = ext4_iget(sb, le32_to_cpu(lrange->fc_ino), EXT4_IGET_NORMAL);
1774 if (IS_ERR(inode)) {
1775 jbd_debug(1, "Inode %d not found", le32_to_cpu(lrange->fc_ino));
1779 ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
1781 jbd_debug(1, "DEL_RANGE, inode %ld, lblk %d, len %d\n",
1782 inode->i_ino, le32_to_cpu(lrange->fc_lblk),
1783 le32_to_cpu(lrange->fc_len));
1784 while (remaining > 0) {
1786 map.m_len = remaining;
1788 ret = ext4_map_blocks(NULL, inode, &map, 0);
1796 ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0);
1798 remaining -= map.m_len;
1803 ret = ext4_punch_hole(inode,
1804 le32_to_cpu(lrange->fc_lblk) << sb->s_blocksize_bits,
1805 le32_to_cpu(lrange->fc_len) << sb->s_blocksize_bits);
1807 jbd_debug(1, "ext4_punch_hole returned %d", ret);
1808 ext4_ext_replay_shrink_inode(inode,
1809 i_size_read(inode) >> sb->s_blocksize_bits);
1810 ext4_mark_inode_dirty(NULL, inode);
1816 static void ext4_fc_set_bitmaps_and_counters(struct super_block *sb)
1818 struct ext4_fc_replay_state *state;
1819 struct inode *inode;
1820 struct ext4_ext_path *path = NULL;
1821 struct ext4_map_blocks map;
1823 ext4_lblk_t cur, end;
1825 state = &EXT4_SB(sb)->s_fc_replay_state;
1826 for (i = 0; i < state->fc_modified_inodes_used; i++) {
1827 inode = ext4_iget(sb, state->fc_modified_inodes[i],
1829 if (IS_ERR(inode)) {
1830 jbd_debug(1, "Inode %d not found.",
1831 state->fc_modified_inodes[i]);
1835 end = EXT_MAX_BLOCKS;
1838 map.m_len = end - cur;
1840 ret = ext4_map_blocks(NULL, inode, &map, 0);
1845 path = ext4_find_extent(inode, map.m_lblk, NULL, 0);
1846 if (!IS_ERR(path)) {
1847 for (j = 0; j < path->p_depth; j++)
1848 ext4_mb_mark_bb(inode->i_sb,
1849 path[j].p_block, 1, 1);
1850 ext4_ext_drop_refs(path);
1854 ext4_mb_mark_bb(inode->i_sb, map.m_pblk,
1857 cur = cur + (map.m_len ? map.m_len : 1);
1865 * Check if block is in excluded regions for block allocation. The simple
1866 * allocator that runs during replay phase is calls this function to see
1867 * if it is okay to use a block.
1869 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t blk)
1872 struct ext4_fc_replay_state *state;
1874 state = &EXT4_SB(sb)->s_fc_replay_state;
1875 for (i = 0; i < state->fc_regions_valid; i++) {
1876 if (state->fc_regions[i].ino == 0 ||
1877 state->fc_regions[i].len == 0)
1879 if (blk >= state->fc_regions[i].pblk &&
1880 blk < state->fc_regions[i].pblk + state->fc_regions[i].len)
1886 /* Cleanup function called after replay */
1887 void ext4_fc_replay_cleanup(struct super_block *sb)
1889 struct ext4_sb_info *sbi = EXT4_SB(sb);
1891 sbi->s_mount_state &= ~EXT4_FC_REPLAY;
1892 kfree(sbi->s_fc_replay_state.fc_regions);
1893 kfree(sbi->s_fc_replay_state.fc_modified_inodes);
1897 * Recovery Scan phase handler
1899 * This function is called during the scan phase and is responsible
1900 * for doing following things:
1901 * - Make sure the fast commit area has valid tags for replay
1902 * - Count number of tags that need to be replayed by the replay handler
1904 * - Create a list of excluded blocks for allocation during replay phase
1906 * This function returns JBD2_FC_REPLAY_CONTINUE to indicate that SCAN is
1907 * incomplete and JBD2 should send more blocks. It returns JBD2_FC_REPLAY_STOP
1908 * to indicate that scan has finished and JBD2 can now start replay phase.
1909 * It returns a negative error to indicate that there was an error. At the end
1910 * of a successful scan phase, sbi->s_fc_replay_state.fc_replay_num_tags is set
1911 * to indicate the number of tags that need to replayed during the replay phase.
1913 static int ext4_fc_replay_scan(journal_t *journal,
1914 struct buffer_head *bh, int off,
1917 struct super_block *sb = journal->j_private;
1918 struct ext4_sb_info *sbi = EXT4_SB(sb);
1919 struct ext4_fc_replay_state *state;
1920 int ret = JBD2_FC_REPLAY_CONTINUE;
1921 struct ext4_fc_add_range *ext;
1922 struct ext4_fc_tl *tl;
1923 struct ext4_fc_tail *tail;
1925 struct ext4_fc_head *head;
1926 struct ext4_extent *ex;
1928 state = &sbi->s_fc_replay_state;
1930 start = (u8 *)bh->b_data;
1931 end = (__u8 *)bh->b_data + journal->j_blocksize - 1;
1933 if (state->fc_replay_expected_off == 0) {
1934 state->fc_cur_tag = 0;
1935 state->fc_replay_num_tags = 0;
1937 state->fc_regions = NULL;
1938 state->fc_regions_valid = state->fc_regions_used =
1939 state->fc_regions_size = 0;
1940 /* Check if we can stop early */
1941 if (le16_to_cpu(((struct ext4_fc_tl *)start)->fc_tag)
1942 != EXT4_FC_TAG_HEAD)
1946 if (off != state->fc_replay_expected_off) {
1947 ret = -EFSCORRUPTED;
1951 state->fc_replay_expected_off++;
1952 fc_for_each_tl(start, end, tl) {
1953 jbd_debug(3, "Scan phase, tag:%s, blk %lld\n",
1954 tag2str(le16_to_cpu(tl->fc_tag)), bh->b_blocknr);
1955 switch (le16_to_cpu(tl->fc_tag)) {
1956 case EXT4_FC_TAG_ADD_RANGE:
1957 ext = (struct ext4_fc_add_range *)ext4_fc_tag_val(tl);
1958 ex = (struct ext4_extent *)&ext->fc_ex;
1959 ret = ext4_fc_record_regions(sb,
1960 le32_to_cpu(ext->fc_ino),
1961 le32_to_cpu(ex->ee_block), ext4_ext_pblock(ex),
1962 ext4_ext_get_actual_len(ex));
1965 ret = JBD2_FC_REPLAY_CONTINUE;
1967 case EXT4_FC_TAG_DEL_RANGE:
1968 case EXT4_FC_TAG_LINK:
1969 case EXT4_FC_TAG_UNLINK:
1970 case EXT4_FC_TAG_CREAT:
1971 case EXT4_FC_TAG_INODE:
1972 case EXT4_FC_TAG_PAD:
1973 state->fc_cur_tag++;
1974 state->fc_crc = ext4_chksum(sbi, state->fc_crc, tl,
1975 sizeof(*tl) + ext4_fc_tag_len(tl));
1977 case EXT4_FC_TAG_TAIL:
1978 state->fc_cur_tag++;
1979 tail = (struct ext4_fc_tail *)ext4_fc_tag_val(tl);
1980 state->fc_crc = ext4_chksum(sbi, state->fc_crc, tl,
1982 offsetof(struct ext4_fc_tail,
1984 if (le32_to_cpu(tail->fc_tid) == expected_tid &&
1985 le32_to_cpu(tail->fc_crc) == state->fc_crc) {
1986 state->fc_replay_num_tags = state->fc_cur_tag;
1987 state->fc_regions_valid =
1988 state->fc_regions_used;
1990 ret = state->fc_replay_num_tags ?
1991 JBD2_FC_REPLAY_STOP : -EFSBADCRC;
1995 case EXT4_FC_TAG_HEAD:
1996 head = (struct ext4_fc_head *)ext4_fc_tag_val(tl);
1997 if (le32_to_cpu(head->fc_features) &
1998 ~EXT4_FC_SUPPORTED_FEATURES) {
2002 if (le32_to_cpu(head->fc_tid) != expected_tid) {
2003 ret = JBD2_FC_REPLAY_STOP;
2006 state->fc_cur_tag++;
2007 state->fc_crc = ext4_chksum(sbi, state->fc_crc, tl,
2008 sizeof(*tl) + ext4_fc_tag_len(tl));
2011 ret = state->fc_replay_num_tags ?
2012 JBD2_FC_REPLAY_STOP : -ECANCELED;
2014 if (ret < 0 || ret == JBD2_FC_REPLAY_STOP)
2019 trace_ext4_fc_replay_scan(sb, ret, off);
2024 * Main recovery path entry point.
2025 * The meaning of return codes is similar as above.
2027 static int ext4_fc_replay(journal_t *journal, struct buffer_head *bh,
2028 enum passtype pass, int off, tid_t expected_tid)
2030 struct super_block *sb = journal->j_private;
2031 struct ext4_sb_info *sbi = EXT4_SB(sb);
2032 struct ext4_fc_tl *tl;
2034 int ret = JBD2_FC_REPLAY_CONTINUE;
2035 struct ext4_fc_replay_state *state = &sbi->s_fc_replay_state;
2036 struct ext4_fc_tail *tail;
2038 if (pass == PASS_SCAN) {
2039 state->fc_current_pass = PASS_SCAN;
2040 return ext4_fc_replay_scan(journal, bh, off, expected_tid);
2043 if (state->fc_current_pass != pass) {
2044 state->fc_current_pass = pass;
2045 sbi->s_mount_state |= EXT4_FC_REPLAY;
2047 if (!sbi->s_fc_replay_state.fc_replay_num_tags) {
2048 jbd_debug(1, "Replay stops\n");
2049 ext4_fc_set_bitmaps_and_counters(sb);
2053 #ifdef CONFIG_EXT4_DEBUG
2054 if (sbi->s_fc_debug_max_replay && off >= sbi->s_fc_debug_max_replay) {
2055 pr_warn("Dropping fc block %d because max_replay set\n", off);
2056 return JBD2_FC_REPLAY_STOP;
2060 start = (u8 *)bh->b_data;
2061 end = (__u8 *)bh->b_data + journal->j_blocksize - 1;
2063 fc_for_each_tl(start, end, tl) {
2064 if (state->fc_replay_num_tags == 0) {
2065 ret = JBD2_FC_REPLAY_STOP;
2066 ext4_fc_set_bitmaps_and_counters(sb);
2069 jbd_debug(3, "Replay phase, tag:%s\n",
2070 tag2str(le16_to_cpu(tl->fc_tag)));
2071 state->fc_replay_num_tags--;
2072 switch (le16_to_cpu(tl->fc_tag)) {
2073 case EXT4_FC_TAG_LINK:
2074 ret = ext4_fc_replay_link(sb, tl);
2076 case EXT4_FC_TAG_UNLINK:
2077 ret = ext4_fc_replay_unlink(sb, tl);
2079 case EXT4_FC_TAG_ADD_RANGE:
2080 ret = ext4_fc_replay_add_range(sb, tl);
2082 case EXT4_FC_TAG_CREAT:
2083 ret = ext4_fc_replay_create(sb, tl);
2085 case EXT4_FC_TAG_DEL_RANGE:
2086 ret = ext4_fc_replay_del_range(sb, tl);
2088 case EXT4_FC_TAG_INODE:
2089 ret = ext4_fc_replay_inode(sb, tl);
2091 case EXT4_FC_TAG_PAD:
2092 trace_ext4_fc_replay(sb, EXT4_FC_TAG_PAD, 0,
2093 ext4_fc_tag_len(tl), 0);
2095 case EXT4_FC_TAG_TAIL:
2096 trace_ext4_fc_replay(sb, EXT4_FC_TAG_TAIL, 0,
2097 ext4_fc_tag_len(tl), 0);
2098 tail = (struct ext4_fc_tail *)ext4_fc_tag_val(tl);
2099 WARN_ON(le32_to_cpu(tail->fc_tid) != expected_tid);
2101 case EXT4_FC_TAG_HEAD:
2104 trace_ext4_fc_replay(sb, le16_to_cpu(tl->fc_tag), 0,
2105 ext4_fc_tag_len(tl), 0);
2111 ret = JBD2_FC_REPLAY_CONTINUE;
2116 void ext4_fc_init(struct super_block *sb, journal_t *journal)
2119 * We set replay callback even if fast commit disabled because we may
2120 * could still have fast commit blocks that need to be replayed even if
2121 * fast commit has now been turned off.
2123 journal->j_fc_replay_callback = ext4_fc_replay;
2124 if (!test_opt2(sb, JOURNAL_FAST_COMMIT))
2126 journal->j_fc_cleanup_callback = ext4_fc_cleanup;
2129 static const char *fc_ineligible_reasons[] = {
2130 "Extended attributes changed",
2132 "Journal flag changed",
2133 "Insufficient memory",
2142 int ext4_fc_info_show(struct seq_file *seq, void *v)
2144 struct ext4_sb_info *sbi = EXT4_SB((struct super_block *)seq->private);
2145 struct ext4_fc_stats *stats = &sbi->s_fc_stats;
2148 if (v != SEQ_START_TOKEN)
2152 "fc stats:\n%ld commits\n%ld ineligible\n%ld numblks\n%lluus avg_commit_time\n",
2153 stats->fc_num_commits, stats->fc_ineligible_commits,
2155 div_u64(sbi->s_fc_avg_commit_time, 1000));
2156 seq_puts(seq, "Ineligible reasons:\n");
2157 for (i = 0; i < EXT4_FC_REASON_MAX; i++)
2158 seq_printf(seq, "\"%s\":\t%d\n", fc_ineligible_reasons[i],
2159 stats->fc_ineligible_reason_count[i]);
2164 int __init ext4_fc_init_dentry_cache(void)
2166 ext4_fc_dentry_cachep = KMEM_CACHE(ext4_fc_dentry_update,
2167 SLAB_RECLAIM_ACCOUNT);
2169 if (ext4_fc_dentry_cachep == NULL)