Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
new file mode 100644
index 0000000..501e607
--- /dev/null
+++ b/fs/ext4/fast_commit.c
@@ -0,0 +1,2181 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * fs/ext4/fast_commit.c
+ *
+ * Written by Harshad Shirwadkar <harshadshirwadkar@gmail.com>
+ *
+ * Ext4 fast commits routines.
+ */
+#include "ext4.h"
+#include "ext4_jbd2.h"
+#include "ext4_extents.h"
+#include "mballoc.h"
+
+/*
+ * Ext4 Fast Commits
+ * -----------------
+ *
+ * Ext4 fast commits implement fine grained journalling for Ext4.
+ *
+ * Fast commits are organized as a log of tag-length-value (TLV) structs. (See
+ * struct ext4_fc_tl). Each TLV contains some delta that is replayed TLV by
+ * TLV during the recovery phase. For the scenarios for which we currently
+ * don't have replay code, fast commit falls back to full commits.
+ * Fast commits record delta in one of the following three categories.
+ *
+ * (A) Directory entry updates:
+ *
+ * - EXT4_FC_TAG_UNLINK - records directory entry unlink
+ * - EXT4_FC_TAG_LINK - records directory entry link
+ * - EXT4_FC_TAG_CREAT - records inode and directory entry creation
+ *
+ * (B) File specific data range updates:
+ *
+ * - EXT4_FC_TAG_ADD_RANGE - records addition of new blocks to an inode
+ * - EXT4_FC_TAG_DEL_RANGE - records deletion of blocks from an inode
+ *
+ * (C) Inode metadata (mtime / ctime etc):
+ *
+ * - EXT4_FC_TAG_INODE - record the inode that should be replayed
+ * during recovery. Note that iblocks field is
+ * not replayed and instead derived during
+ * replay.
+ * Commit Operation
+ * ----------------
+ * With fast commits, we maintain all the directory entry operations in the
+ * order in which they are issued in an in-memory queue. This queue is flushed
+ * to disk during the commit operation. We also maintain a list of inodes
+ * that need to be committed during a fast commit in another in memory queue of
+ * inodes. During the commit operation, we commit in the following order:
+ *
+ * [1] Lock inodes for any further data updates by setting COMMITTING state
+ * [2] Submit data buffers of all the inodes
+ * [3] Wait for [2] to complete
+ * [4] Commit all the directory entry updates in the fast commit space
+ * [5] Commit all the changed inode structures
+ * [6] Write tail tag (this tag ensures the atomicity, please read the following
+ * section for more details).
+ * [7] Wait for [4], [5] and [6] to complete.
+ *
+ * All the inode updates must call ext4_fc_start_update() before starting an
+ * update. If such an ongoing update is present, fast commit waits for it to
+ * complete. The completion of such an update is marked by
+ * ext4_fc_stop_update().
+ *
+ * Fast Commit Ineligibility
+ * -------------------------
+ * Not all operations are supported by fast commits today (e.g extended
+ * attributes). Fast commit ineligiblity is marked by calling one of the
+ * two following functions:
+ *
+ * - ext4_fc_mark_ineligible(): This makes next fast commit operation to fall
+ * back to full commit. This is useful in case of transient errors.
+ *
+ * - ext4_fc_start_ineligible() and ext4_fc_stop_ineligible() - This makes all
+ * the fast commits happening between ext4_fc_start_ineligible() and
+ * ext4_fc_stop_ineligible() and one fast commit after the call to
+ * ext4_fc_stop_ineligible() to fall back to full commits. It is important to
+ * make one more fast commit to fall back to full commit after stop call so
+ * that it guaranteed that the fast commit ineligible operation contained
+ * within ext4_fc_start_ineligible() and ext4_fc_stop_ineligible() is
+ * followed by at least 1 full commit.
+ *
+ * Atomicity of commits
+ * --------------------
+ * In order to guarantee atomicity during the commit operation, fast commit
+ * uses "EXT4_FC_TAG_TAIL" tag that marks a fast commit as complete. Tail
+ * tag contains CRC of the contents and TID of the transaction after which
+ * this fast commit should be applied. Recovery code replays fast commit
+ * logs only if there's at least 1 valid tail present. For every fast commit
+ * operation, there is 1 tail. This means, we may end up with multiple tails
+ * in the fast commit space. Here's an example:
+ *
+ * - Create a new file A and remove existing file B
+ * - fsync()
+ * - Append contents to file A
+ * - Truncate file A
+ * - fsync()
+ *
+ * The fast commit space at the end of above operations would look like this:
+ * [HEAD] [CREAT A] [UNLINK B] [TAIL] [ADD_RANGE A] [DEL_RANGE A] [TAIL]
+ * |<--- Fast Commit 1 --->|<--- Fast Commit 2 ---->|
+ *
+ * Replay code should thus check for all the valid tails in the FC area.
+ *
+ * TODOs
+ * -----
+ * 1) Make fast commit atomic updates more fine grained. Today, a fast commit
+ * eligible update must be protected within ext4_fc_start_update() and
+ * ext4_fc_stop_update(). These routines are called at much higher
+ * routines. This can be made more fine grained by combining with
+ * ext4_journal_start().
+ *
+ * 2) Same above for ext4_fc_start_ineligible() and ext4_fc_stop_ineligible()
+ *
+ * 3) Handle more ineligible cases.
+ */
+
+#include <trace/events/ext4.h>
+static struct kmem_cache *ext4_fc_dentry_cachep;
+
+static void ext4_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
+{
+ BUFFER_TRACE(bh, "");
+ if (uptodate) {
+ ext4_debug("%s: Block %lld up-to-date",
+ __func__, bh->b_blocknr);
+ set_buffer_uptodate(bh);
+ } else {
+ ext4_debug("%s: Block %lld not up-to-date",
+ __func__, bh->b_blocknr);
+ clear_buffer_uptodate(bh);
+ }
+
+ unlock_buffer(bh);
+}
+
+static inline void ext4_fc_reset_inode(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ ei->i_fc_lblk_start = 0;
+ ei->i_fc_lblk_len = 0;
+}
+
+void ext4_fc_init_inode(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ ext4_fc_reset_inode(inode);
+ ext4_clear_inode_state(inode, EXT4_STATE_FC_COMMITTING);
+ INIT_LIST_HEAD(&ei->i_fc_list);
+ init_waitqueue_head(&ei->i_fc_wait);
+ atomic_set(&ei->i_fc_updates, 0);
+}
+
+/* This function must be called with sbi->s_fc_lock held. */
+static void ext4_fc_wait_committing_inode(struct inode *inode)
+__releases(&EXT4_SB(inode->i_sb)->s_fc_lock)
+{
+ wait_queue_head_t *wq;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+#if (BITS_PER_LONG < 64)
+ DEFINE_WAIT_BIT(wait, &ei->i_state_flags,
+ EXT4_STATE_FC_COMMITTING);
+ wq = bit_waitqueue(&ei->i_state_flags,
+ EXT4_STATE_FC_COMMITTING);
+#else
+ DEFINE_WAIT_BIT(wait, &ei->i_flags,
+ EXT4_STATE_FC_COMMITTING);
+ wq = bit_waitqueue(&ei->i_flags,
+ EXT4_STATE_FC_COMMITTING);
+#endif
+ lockdep_assert_held(&EXT4_SB(inode->i_sb)->s_fc_lock);
+ prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
+ spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+ schedule();
+ finish_wait(wq, &wait.wq_entry);
+}
+
+/*
+ * Inform Ext4's fast about start of an inode update
+ *
+ * This function is called by the high level call VFS callbacks before
+ * performing any inode update. This function blocks if there's an ongoing
+ * fast commit on the inode in question.
+ */
+void ext4_fc_start_update(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+restart:
+ spin_lock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+ if (list_empty(&ei->i_fc_list))
+ goto out;
+
+ if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) {
+ ext4_fc_wait_committing_inode(inode);
+ goto restart;
+ }
+out:
+ atomic_inc(&ei->i_fc_updates);
+ spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+}
+
+/*
+ * Stop inode update and wake up waiting fast commits if any.
+ */
+void ext4_fc_stop_update(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+ if (atomic_dec_and_test(&ei->i_fc_updates))
+ wake_up_all(&ei->i_fc_wait);
+}
+
+/*
+ * Remove inode from fast commit list. If the inode is being committed
+ * we wait until inode commit is done.
+ */
+void ext4_fc_del(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+restart:
+ spin_lock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+ if (list_empty(&ei->i_fc_list)) {
+ spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+ return;
+ }
+
+ if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) {
+ ext4_fc_wait_committing_inode(inode);
+ goto restart;
+ }
+ list_del_init(&ei->i_fc_list);
+ spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
+}
+
+/*
+ * Mark file system as fast commit ineligible. This means that next commit
+ * operation would result in a full jbd2 commit.
+ */
+void ext4_fc_mark_ineligible(struct super_block *sb, int reason)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+ ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
+ WARN_ON(reason >= EXT4_FC_REASON_MAX);
+ sbi->s_fc_stats.fc_ineligible_reason_count[reason]++;
+}
+
+/*
+ * Start a fast commit ineligible update. Any commits that happen while
+ * such an operation is in progress fall back to full commits.
+ */
+void ext4_fc_start_ineligible(struct super_block *sb, int reason)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+ WARN_ON(reason >= EXT4_FC_REASON_MAX);
+ sbi->s_fc_stats.fc_ineligible_reason_count[reason]++;
+ atomic_inc(&sbi->s_fc_ineligible_updates);
+}
+
+/*
+ * Stop a fast commit ineligible update. We set EXT4_MF_FC_INELIGIBLE flag here
+ * to ensure that after stopping the ineligible update, at least one full
+ * commit takes place.
+ */
+void ext4_fc_stop_ineligible(struct super_block *sb)
+{
+ if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
+ (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))
+ return;
+
+ ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
+ atomic_dec(&EXT4_SB(sb)->s_fc_ineligible_updates);
+}
+
+static inline int ext4_fc_is_ineligible(struct super_block *sb)
+{
+ return (ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE) ||
+ atomic_read(&EXT4_SB(sb)->s_fc_ineligible_updates));
+}
+
+/*
+ * Generic fast commit tracking function. If this is the first time this we are
+ * called after a full commit, we initialize fast commit fields and then call
+ * __fc_track_fn() with update = 0. If we have already been called after a full
+ * commit, we pass update = 1. Based on that, the track function can determine
+ * if it needs to track a field for the first time or if it needs to just
+ * update the previously tracked value.
+ *
+ * If enqueue is set, this function enqueues the inode in fast commit list.
+ */
+static int ext4_fc_track_template(
+ handle_t *handle, struct inode *inode,
+ int (*__fc_track_fn)(struct inode *, void *, bool),
+ void *args, int enqueue)
+{
+ bool update = false;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ tid_t tid = 0;
+ int ret;
+
+ if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+ (sbi->s_mount_state & EXT4_FC_REPLAY))
+ return -EOPNOTSUPP;
+
+ if (ext4_fc_is_ineligible(inode->i_sb))
+ return -EINVAL;
+
+ tid = handle->h_transaction->t_tid;
+ mutex_lock(&ei->i_fc_lock);
+ if (tid == ei->i_sync_tid) {
+ update = true;
+ } else {
+ ext4_fc_reset_inode(inode);
+ ei->i_sync_tid = tid;
+ }
+ ret = __fc_track_fn(inode, args, update);
+ mutex_unlock(&ei->i_fc_lock);
+
+ if (!enqueue)
+ return ret;
+
+ spin_lock(&sbi->s_fc_lock);
+ if (list_empty(&EXT4_I(inode)->i_fc_list))
+ list_add_tail(&EXT4_I(inode)->i_fc_list,
+ (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_COMMITTING)) ?
+ &sbi->s_fc_q[FC_Q_STAGING] :
+ &sbi->s_fc_q[FC_Q_MAIN]);
+ spin_unlock(&sbi->s_fc_lock);
+
+ return ret;
+}
+
+struct __track_dentry_update_args {
+ struct dentry *dentry;
+ int op;
+};
+
+/* __track_fn for directory entry updates. Called with ei->i_fc_lock. */
+static int __track_dentry_update(struct inode *inode, void *arg, bool update)
+{
+ struct ext4_fc_dentry_update *node;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct __track_dentry_update_args *dentry_update =
+ (struct __track_dentry_update_args *)arg;
+ struct dentry *dentry = dentry_update->dentry;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+ mutex_unlock(&ei->i_fc_lock);
+ node = kmem_cache_alloc(ext4_fc_dentry_cachep, GFP_NOFS);
+ if (!node) {
+ ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_NOMEM);
+ mutex_lock(&ei->i_fc_lock);
+ return -ENOMEM;
+ }
+
+ node->fcd_op = dentry_update->op;
+ node->fcd_parent = dentry->d_parent->d_inode->i_ino;
+ node->fcd_ino = inode->i_ino;
+ if (dentry->d_name.len > DNAME_INLINE_LEN) {
+ node->fcd_name.name = kmalloc(dentry->d_name.len, GFP_NOFS);
+ if (!node->fcd_name.name) {
+ kmem_cache_free(ext4_fc_dentry_cachep, node);
+ ext4_fc_mark_ineligible(inode->i_sb,
+ EXT4_FC_REASON_NOMEM);
+ mutex_lock(&ei->i_fc_lock);
+ return -ENOMEM;
+ }
+ memcpy((u8 *)node->fcd_name.name, dentry->d_name.name,
+ dentry->d_name.len);
+ } else {
+ memcpy(node->fcd_iname, dentry->d_name.name,
+ dentry->d_name.len);
+ node->fcd_name.name = node->fcd_iname;
+ }
+ node->fcd_name.len = dentry->d_name.len;
+
+ spin_lock(&sbi->s_fc_lock);
+ if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_COMMITTING))
+ list_add_tail(&node->fcd_list,
+ &sbi->s_fc_dentry_q[FC_Q_STAGING]);
+ else
+ list_add_tail(&node->fcd_list, &sbi->s_fc_dentry_q[FC_Q_MAIN]);
+ spin_unlock(&sbi->s_fc_lock);
+ mutex_lock(&ei->i_fc_lock);
+
+ return 0;
+}
+
+void __ext4_fc_track_unlink(handle_t *handle,
+ struct inode *inode, struct dentry *dentry)
+{
+ struct __track_dentry_update_args args;
+ int ret;
+
+ args.dentry = dentry;
+ args.op = EXT4_FC_TAG_UNLINK;
+
+ ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
+ (void *)&args, 0);
+ trace_ext4_fc_track_unlink(inode, dentry, ret);
+}
+
+void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry)
+{
+ __ext4_fc_track_unlink(handle, d_inode(dentry), dentry);
+}
+
+void __ext4_fc_track_link(handle_t *handle,
+ struct inode *inode, struct dentry *dentry)
+{
+ struct __track_dentry_update_args args;
+ int ret;
+
+ args.dentry = dentry;
+ args.op = EXT4_FC_TAG_LINK;
+
+ ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
+ (void *)&args, 0);
+ trace_ext4_fc_track_link(inode, dentry, ret);
+}
+
+void ext4_fc_track_link(handle_t *handle, struct dentry *dentry)
+{
+ __ext4_fc_track_link(handle, d_inode(dentry), dentry);
+}
+
+void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
+ struct dentry *dentry)
+{
+ struct __track_dentry_update_args args;
+ int ret;
+
+ args.dentry = dentry;
+ args.op = EXT4_FC_TAG_CREAT;
+
+ ret = ext4_fc_track_template(handle, inode, __track_dentry_update,
+ (void *)&args, 0);
+ trace_ext4_fc_track_create(inode, dentry, ret);
+}
+
+void ext4_fc_track_create(handle_t *handle, struct dentry *dentry)
+{
+ __ext4_fc_track_create(handle, d_inode(dentry), dentry);
+}
+
+/* __track_fn for inode tracking */
+static int __track_inode(struct inode *inode, void *arg, bool update)
+{
+ if (update)
+ return -EEXIST;
+
+ EXT4_I(inode)->i_fc_lblk_len = 0;
+
+ return 0;
+}
+
+void ext4_fc_track_inode(handle_t *handle, struct inode *inode)
+{
+ int ret;
+
+ if (S_ISDIR(inode->i_mode))
+ return;
+
+ if (ext4_should_journal_data(inode)) {
+ ext4_fc_mark_ineligible(inode->i_sb,
+ EXT4_FC_REASON_INODE_JOURNAL_DATA);
+ return;
+ }
+
+ ret = ext4_fc_track_template(handle, inode, __track_inode, NULL, 1);
+ trace_ext4_fc_track_inode(inode, ret);
+}
+
+struct __track_range_args {
+ ext4_lblk_t start, end;
+};
+
+/* __track_fn for tracking data updates */
+static int __track_range(struct inode *inode, void *arg, bool update)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ ext4_lblk_t oldstart;
+ struct __track_range_args *__arg =
+ (struct __track_range_args *)arg;
+
+ if (inode->i_ino < EXT4_FIRST_INO(inode->i_sb)) {
+ ext4_debug("Special inode %ld being modified\n", inode->i_ino);
+ return -ECANCELED;
+ }
+
+ oldstart = ei->i_fc_lblk_start;
+
+ if (update && ei->i_fc_lblk_len > 0) {
+ ei->i_fc_lblk_start = min(ei->i_fc_lblk_start, __arg->start);
+ ei->i_fc_lblk_len =
+ max(oldstart + ei->i_fc_lblk_len - 1, __arg->end) -
+ ei->i_fc_lblk_start + 1;
+ } else {
+ ei->i_fc_lblk_start = __arg->start;
+ ei->i_fc_lblk_len = __arg->end - __arg->start + 1;
+ }
+
+ return 0;
+}
+
+void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
+ ext4_lblk_t end)
+{
+ struct __track_range_args args;
+ int ret;
+
+ if (S_ISDIR(inode->i_mode))
+ return;
+
+ args.start = start;
+ args.end = end;
+
+ ret = ext4_fc_track_template(handle, inode, __track_range, &args, 1);
+
+ trace_ext4_fc_track_range(inode, start, end, ret);
+}
+
+static void ext4_fc_submit_bh(struct super_block *sb)
+{
+ int write_flags = REQ_SYNC;
+ struct buffer_head *bh = EXT4_SB(sb)->s_fc_bh;
+
+ /* TODO: REQ_FUA | REQ_PREFLUSH is unnecessarily expensive. */
+ if (test_opt(sb, BARRIER))
+ write_flags |= REQ_FUA | REQ_PREFLUSH;
+ lock_buffer(bh);
+ set_buffer_dirty(bh);
+ set_buffer_uptodate(bh);
+ bh->b_end_io = ext4_end_buffer_io_sync;
+ submit_bh(REQ_OP_WRITE, write_flags, bh);
+ EXT4_SB(sb)->s_fc_bh = NULL;
+}
+
+/* Ext4 commit path routines */
+
+/* memzero and update CRC */
+static void *ext4_fc_memzero(struct super_block *sb, void *dst, int len,
+ u32 *crc)
+{
+ void *ret;
+
+ ret = memset(dst, 0, len);
+ if (crc)
+ *crc = ext4_chksum(EXT4_SB(sb), *crc, dst, len);
+ return ret;
+}
+
+/*
+ * Allocate len bytes on a fast commit buffer.
+ *
+ * During the commit time this function is used to manage fast commit
+ * block space. We don't split a fast commit log onto different
+ * blocks. So this function makes sure that if there's not enough space
+ * on the current block, the remaining space in the current block is
+ * marked as unused by adding EXT4_FC_TAG_PAD tag. In that case,
+ * new block is from jbd2 and CRC is updated to reflect the padding
+ * we added.
+ */
+static u8 *ext4_fc_reserve_space(struct super_block *sb, int len, u32 *crc)
+{
+ struct ext4_fc_tl *tl;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct buffer_head *bh;
+ int bsize = sbi->s_journal->j_blocksize;
+ int ret, off = sbi->s_fc_bytes % bsize;
+ int pad_len;
+
+ /*
+ * After allocating len, we should have space at least for a 0 byte
+ * padding.
+ */
+ if (len + sizeof(struct ext4_fc_tl) > bsize)
+ return NULL;
+
+ if (bsize - off - 1 > len + sizeof(struct ext4_fc_tl)) {
+ /*
+ * Only allocate from current buffer if we have enough space for
+ * this request AND we have space to add a zero byte padding.
+ */
+ if (!sbi->s_fc_bh) {
+ ret = jbd2_fc_get_buf(EXT4_SB(sb)->s_journal, &bh);
+ if (ret)
+ return NULL;
+ sbi->s_fc_bh = bh;
+ }
+ sbi->s_fc_bytes += len;
+ return sbi->s_fc_bh->b_data + off;
+ }
+ /* Need to add PAD tag */
+ tl = (struct ext4_fc_tl *)(sbi->s_fc_bh->b_data + off);
+ tl->fc_tag = cpu_to_le16(EXT4_FC_TAG_PAD);
+ pad_len = bsize - off - 1 - sizeof(struct ext4_fc_tl);
+ tl->fc_len = cpu_to_le16(pad_len);
+ if (crc)
+ *crc = ext4_chksum(sbi, *crc, tl, sizeof(*tl));
+ if (pad_len > 0)
+ ext4_fc_memzero(sb, tl + 1, pad_len, crc);
+ ext4_fc_submit_bh(sb);
+
+ ret = jbd2_fc_get_buf(EXT4_SB(sb)->s_journal, &bh);
+ if (ret)
+ return NULL;
+ sbi->s_fc_bh = bh;
+ sbi->s_fc_bytes = (sbi->s_fc_bytes / bsize + 1) * bsize + len;
+ return sbi->s_fc_bh->b_data;
+}
+
+/* memcpy to fc reserved space and update CRC */
+static void *ext4_fc_memcpy(struct super_block *sb, void *dst, const void *src,
+ int len, u32 *crc)
+{
+ if (crc)
+ *crc = ext4_chksum(EXT4_SB(sb), *crc, src, len);
+ return memcpy(dst, src, len);
+}
+
+/*
+ * Complete a fast commit by writing tail tag.
+ *
+ * Writing tail tag marks the end of a fast commit. In order to guarantee
+ * atomicity, after writing tail tag, even if there's space remaining
+ * in the block, next commit shouldn't use it. That's why tail tag
+ * has the length as that of the remaining space on the block.
+ */
+static int ext4_fc_write_tail(struct super_block *sb, u32 crc)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_fc_tl tl;
+ struct ext4_fc_tail tail;
+ int off, bsize = sbi->s_journal->j_blocksize;
+ u8 *dst;
+
+ /*
+ * ext4_fc_reserve_space takes care of allocating an extra block if
+ * there's no enough space on this block for accommodating this tail.
+ */
+ dst = ext4_fc_reserve_space(sb, sizeof(tl) + sizeof(tail), &crc);
+ if (!dst)
+ return -ENOSPC;
+
+ off = sbi->s_fc_bytes % bsize;
+
+ tl.fc_tag = cpu_to_le16(EXT4_FC_TAG_TAIL);
+ tl.fc_len = cpu_to_le16(bsize - off - 1 + sizeof(struct ext4_fc_tail));
+ sbi->s_fc_bytes = round_up(sbi->s_fc_bytes, bsize);
+
+ ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), &crc);
+ dst += sizeof(tl);
+ tail.fc_tid = cpu_to_le32(sbi->s_journal->j_running_transaction->t_tid);
+ ext4_fc_memcpy(sb, dst, &tail.fc_tid, sizeof(tail.fc_tid), &crc);
+ dst += sizeof(tail.fc_tid);
+ tail.fc_crc = cpu_to_le32(crc);
+ ext4_fc_memcpy(sb, dst, &tail.fc_crc, sizeof(tail.fc_crc), NULL);
+
+ ext4_fc_submit_bh(sb);
+
+ return 0;
+}
+
+/*
+ * Adds tag, length, value and updates CRC. Returns true if tlv was added.
+ * Returns false if there's not enough space.
+ */
+static bool ext4_fc_add_tlv(struct super_block *sb, u16 tag, u16 len, u8 *val,
+ u32 *crc)
+{
+ struct ext4_fc_tl tl;
+ u8 *dst;
+
+ dst = ext4_fc_reserve_space(sb, sizeof(tl) + len, crc);
+ if (!dst)
+ return false;
+
+ tl.fc_tag = cpu_to_le16(tag);
+ tl.fc_len = cpu_to_le16(len);
+
+ ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), crc);
+ ext4_fc_memcpy(sb, dst + sizeof(tl), val, len, crc);
+
+ return true;
+}
+
+/* Same as above, but adds dentry tlv. */
+static bool ext4_fc_add_dentry_tlv(struct super_block *sb, u16 tag,
+ int parent_ino, int ino, int dlen,
+ const unsigned char *dname,
+ u32 *crc)
+{
+ struct ext4_fc_dentry_info fcd;
+ struct ext4_fc_tl tl;
+ u8 *dst = ext4_fc_reserve_space(sb, sizeof(tl) + sizeof(fcd) + dlen,
+ crc);
+
+ if (!dst)
+ return false;
+
+ fcd.fc_parent_ino = cpu_to_le32(parent_ino);
+ fcd.fc_ino = cpu_to_le32(ino);
+ tl.fc_tag = cpu_to_le16(tag);
+ tl.fc_len = cpu_to_le16(sizeof(fcd) + dlen);
+ ext4_fc_memcpy(sb, dst, &tl, sizeof(tl), crc);
+ dst += sizeof(tl);
+ ext4_fc_memcpy(sb, dst, &fcd, sizeof(fcd), crc);
+ dst += sizeof(fcd);
+ ext4_fc_memcpy(sb, dst, dname, dlen, crc);
+ dst += dlen;
+
+ return true;
+}
+
+/*
+ * Writes inode in the fast commit space under TLV with tag @tag.
+ * Returns 0 on success, error on failure.
+ */
+static int ext4_fc_write_inode(struct inode *inode, u32 *crc)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ int inode_len = EXT4_GOOD_OLD_INODE_SIZE;
+ int ret;
+ struct ext4_iloc iloc;
+ struct ext4_fc_inode fc_inode;
+ struct ext4_fc_tl tl;
+ u8 *dst;
+
+ ret = ext4_get_inode_loc(inode, &iloc);
+ if (ret)
+ return ret;
+
+ if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE)
+ inode_len += ei->i_extra_isize;
+
+ fc_inode.fc_ino = cpu_to_le32(inode->i_ino);
+ tl.fc_tag = cpu_to_le16(EXT4_FC_TAG_INODE);
+ tl.fc_len = cpu_to_le16(inode_len + sizeof(fc_inode.fc_ino));
+
+ dst = ext4_fc_reserve_space(inode->i_sb,
+ sizeof(tl) + inode_len + sizeof(fc_inode.fc_ino), crc);
+ if (!dst)
+ return -ECANCELED;
+
+ if (!ext4_fc_memcpy(inode->i_sb, dst, &tl, sizeof(tl), crc))
+ return -ECANCELED;
+ dst += sizeof(tl);
+ if (!ext4_fc_memcpy(inode->i_sb, dst, &fc_inode, sizeof(fc_inode), crc))
+ return -ECANCELED;
+ dst += sizeof(fc_inode);
+ if (!ext4_fc_memcpy(inode->i_sb, dst, (u8 *)ext4_raw_inode(&iloc),
+ inode_len, crc))
+ return -ECANCELED;
+
+ return 0;
+}
+
+/*
+ * Writes updated data ranges for the inode in question. Updates CRC.
+ * Returns 0 on success, error otherwise.
+ */
+static int ext4_fc_write_inode_data(struct inode *inode, u32 *crc)
+{
+ ext4_lblk_t old_blk_size, cur_lblk_off, new_blk_size;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_map_blocks map;
+ struct ext4_fc_add_range fc_ext;
+ struct ext4_fc_del_range lrange;
+ struct ext4_extent *ex;
+ int ret;
+
+ mutex_lock(&ei->i_fc_lock);
+ if (ei->i_fc_lblk_len == 0) {
+ mutex_unlock(&ei->i_fc_lock);
+ return 0;
+ }
+ old_blk_size = ei->i_fc_lblk_start;
+ new_blk_size = ei->i_fc_lblk_start + ei->i_fc_lblk_len - 1;
+ ei->i_fc_lblk_len = 0;
+ mutex_unlock(&ei->i_fc_lock);
+
+ cur_lblk_off = old_blk_size;
+ jbd_debug(1, "%s: will try writing %d to %d for inode %ld\n",
+ __func__, cur_lblk_off, new_blk_size, inode->i_ino);
+
+ while (cur_lblk_off <= new_blk_size) {
+ map.m_lblk = cur_lblk_off;
+ map.m_len = new_blk_size - cur_lblk_off + 1;
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret < 0)
+ return -ECANCELED;
+
+ if (map.m_len == 0) {
+ cur_lblk_off++;
+ continue;
+ }
+
+ if (ret == 0) {
+ lrange.fc_ino = cpu_to_le32(inode->i_ino);
+ lrange.fc_lblk = cpu_to_le32(map.m_lblk);
+ lrange.fc_len = cpu_to_le32(map.m_len);
+ if (!ext4_fc_add_tlv(inode->i_sb, EXT4_FC_TAG_DEL_RANGE,
+ sizeof(lrange), (u8 *)&lrange, crc))
+ return -ENOSPC;
+ } else {
+ unsigned int max = (map.m_flags & EXT4_MAP_UNWRITTEN) ?
+ EXT_UNWRITTEN_MAX_LEN : EXT_INIT_MAX_LEN;
+
+ /* Limit the number of blocks in one extent */
+ map.m_len = min(max, map.m_len);
+
+ fc_ext.fc_ino = cpu_to_le32(inode->i_ino);
+ ex = (struct ext4_extent *)&fc_ext.fc_ex;
+ ex->ee_block = cpu_to_le32(map.m_lblk);
+ ex->ee_len = cpu_to_le16(map.m_len);
+ ext4_ext_store_pblock(ex, map.m_pblk);
+ if (map.m_flags & EXT4_MAP_UNWRITTEN)
+ ext4_ext_mark_unwritten(ex);
+ else
+ ext4_ext_mark_initialized(ex);
+ if (!ext4_fc_add_tlv(inode->i_sb, EXT4_FC_TAG_ADD_RANGE,
+ sizeof(fc_ext), (u8 *)&fc_ext, crc))
+ return -ENOSPC;
+ }
+
+ cur_lblk_off += map.m_len;
+ }
+
+ return 0;
+}
+
+
+/* Submit data for all the fast commit inodes */
+static int ext4_fc_submit_inode_data_all(journal_t *journal)
+{
+ struct super_block *sb = (struct super_block *)(journal->j_private);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_inode_info *ei;
+ struct list_head *pos;
+ int ret = 0;
+
+ spin_lock(&sbi->s_fc_lock);
+ ext4_set_mount_flag(sb, EXT4_MF_FC_COMMITTING);
+ list_for_each(pos, &sbi->s_fc_q[FC_Q_MAIN]) {
+ ei = list_entry(pos, struct ext4_inode_info, i_fc_list);
+ ext4_set_inode_state(&ei->vfs_inode, EXT4_STATE_FC_COMMITTING);
+ while (atomic_read(&ei->i_fc_updates)) {
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(&ei->i_fc_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ if (atomic_read(&ei->i_fc_updates)) {
+ spin_unlock(&sbi->s_fc_lock);
+ schedule();
+ spin_lock(&sbi->s_fc_lock);
+ }
+ finish_wait(&ei->i_fc_wait, &wait);
+ }
+ spin_unlock(&sbi->s_fc_lock);
+ ret = jbd2_submit_inode_data(ei->jinode);
+ if (ret)
+ return ret;
+ spin_lock(&sbi->s_fc_lock);
+ }
+ spin_unlock(&sbi->s_fc_lock);
+
+ return ret;
+}
+
+/* Wait for completion of data for all the fast commit inodes */
+static int ext4_fc_wait_inode_data_all(journal_t *journal)
+{
+ struct super_block *sb = (struct super_block *)(journal->j_private);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_inode_info *pos, *n;
+ int ret = 0;
+
+ spin_lock(&sbi->s_fc_lock);
+ list_for_each_entry_safe(pos, n, &sbi->s_fc_q[FC_Q_MAIN], i_fc_list) {
+ if (!ext4_test_inode_state(&pos->vfs_inode,
+ EXT4_STATE_FC_COMMITTING))
+ continue;
+ spin_unlock(&sbi->s_fc_lock);
+
+ ret = jbd2_wait_inode_data(journal, pos->jinode);
+ if (ret)
+ return ret;
+ spin_lock(&sbi->s_fc_lock);
+ }
+ spin_unlock(&sbi->s_fc_lock);
+
+ return 0;
+}
+
+/* Commit all the directory entry updates */
+static int ext4_fc_commit_dentry_updates(journal_t *journal, u32 *crc)
+__acquires(&sbi->s_fc_lock)
+__releases(&sbi->s_fc_lock)
+{
+ struct super_block *sb = (struct super_block *)(journal->j_private);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_fc_dentry_update *fc_dentry;
+ struct inode *inode;
+ struct list_head *pos, *n, *fcd_pos, *fcd_n;
+ struct ext4_inode_info *ei;
+ int ret;
+
+ if (list_empty(&sbi->s_fc_dentry_q[FC_Q_MAIN]))
+ return 0;
+ list_for_each_safe(fcd_pos, fcd_n, &sbi->s_fc_dentry_q[FC_Q_MAIN]) {
+ fc_dentry = list_entry(fcd_pos, struct ext4_fc_dentry_update,
+ fcd_list);
+ if (fc_dentry->fcd_op != EXT4_FC_TAG_CREAT) {
+ spin_unlock(&sbi->s_fc_lock);
+ if (!ext4_fc_add_dentry_tlv(
+ sb, fc_dentry->fcd_op,
+ fc_dentry->fcd_parent, fc_dentry->fcd_ino,
+ fc_dentry->fcd_name.len,
+ fc_dentry->fcd_name.name, crc)) {
+ ret = -ENOSPC;
+ goto lock_and_exit;
+ }
+ spin_lock(&sbi->s_fc_lock);
+ continue;
+ }
+
+ inode = NULL;
+ list_for_each_safe(pos, n, &sbi->s_fc_q[FC_Q_MAIN]) {
+ ei = list_entry(pos, struct ext4_inode_info, i_fc_list);
+ if (ei->vfs_inode.i_ino == fc_dentry->fcd_ino) {
+ inode = &ei->vfs_inode;
+ break;
+ }
+ }
+ /*
+ * If we don't find inode in our list, then it was deleted,
+ * in which case, we don't need to record it's create tag.
+ */
+ if (!inode)
+ continue;
+ spin_unlock(&sbi->s_fc_lock);
+
+ /*
+ * We first write the inode and then the create dirent. This
+ * allows the recovery code to create an unnamed inode first
+ * and then link it to a directory entry. This allows us
+ * to use namei.c routines almost as is and simplifies
+ * the recovery code.
+ */
+ ret = ext4_fc_write_inode(inode, crc);
+ if (ret)
+ goto lock_and_exit;
+
+ ret = ext4_fc_write_inode_data(inode, crc);
+ if (ret)
+ goto lock_and_exit;
+
+ if (!ext4_fc_add_dentry_tlv(
+ sb, fc_dentry->fcd_op,
+ fc_dentry->fcd_parent, fc_dentry->fcd_ino,
+ fc_dentry->fcd_name.len,
+ fc_dentry->fcd_name.name, crc)) {
+ ret = -ENOSPC;
+ goto lock_and_exit;
+ }
+
+ spin_lock(&sbi->s_fc_lock);
+ }
+ return 0;
+lock_and_exit:
+ spin_lock(&sbi->s_fc_lock);
+ return ret;
+}
+
+static int ext4_fc_perform_commit(journal_t *journal)
+{
+ struct super_block *sb = (struct super_block *)(journal->j_private);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_inode_info *iter;
+ struct ext4_fc_head head;
+ struct list_head *pos;
+ struct inode *inode;
+ struct blk_plug plug;
+ int ret = 0;
+ u32 crc = 0;
+
+ ret = ext4_fc_submit_inode_data_all(journal);
+ if (ret)
+ return ret;
+
+ ret = ext4_fc_wait_inode_data_all(journal);
+ if (ret)
+ return ret;
+
+ /*
+ * If file system device is different from journal device, issue a cache
+ * flush before we start writing fast commit blocks.
+ */
+ if (journal->j_fs_dev != journal->j_dev)
+ blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS);
+
+ blk_start_plug(&plug);
+ if (sbi->s_fc_bytes == 0) {
+ /*
+ * Add a head tag only if this is the first fast commit
+ * in this TID.
+ */
+ head.fc_features = cpu_to_le32(EXT4_FC_SUPPORTED_FEATURES);
+ head.fc_tid = cpu_to_le32(
+ sbi->s_journal->j_running_transaction->t_tid);
+ if (!ext4_fc_add_tlv(sb, EXT4_FC_TAG_HEAD, sizeof(head),
+ (u8 *)&head, &crc)) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ }
+
+ spin_lock(&sbi->s_fc_lock);
+ ret = ext4_fc_commit_dentry_updates(journal, &crc);
+ if (ret) {
+ spin_unlock(&sbi->s_fc_lock);
+ goto out;
+ }
+
+ list_for_each(pos, &sbi->s_fc_q[FC_Q_MAIN]) {
+ iter = list_entry(pos, struct ext4_inode_info, i_fc_list);
+ inode = &iter->vfs_inode;
+ if (!ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING))
+ continue;
+
+ spin_unlock(&sbi->s_fc_lock);
+ ret = ext4_fc_write_inode_data(inode, &crc);
+ if (ret)
+ goto out;
+ ret = ext4_fc_write_inode(inode, &crc);
+ if (ret)
+ goto out;
+ spin_lock(&sbi->s_fc_lock);
+ }
+ spin_unlock(&sbi->s_fc_lock);
+
+ ret = ext4_fc_write_tail(sb, crc);
+
+out:
+ blk_finish_plug(&plug);
+ return ret;
+}
+
+/*
+ * The main commit entry point. Performs a fast commit for transaction
+ * commit_tid if needed. If it's not possible to perform a fast commit
+ * due to various reasons, we fall back to full commit. Returns 0
+ * on success, error otherwise.
+ */
+int ext4_fc_commit(journal_t *journal, tid_t commit_tid)
+{
+ struct super_block *sb = (struct super_block *)(journal->j_private);
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ int nblks = 0, ret, bsize = journal->j_blocksize;
+ int subtid = atomic_read(&sbi->s_fc_subtid);
+ int reason = EXT4_FC_REASON_OK, fc_bufs_before = 0;
+ ktime_t start_time, commit_time;
+
+ trace_ext4_fc_commit_start(sb);
+
+ start_time = ktime_get();
+
+ if (!test_opt2(sb, JOURNAL_FAST_COMMIT) ||
+ (ext4_fc_is_ineligible(sb))) {
+ reason = EXT4_FC_REASON_INELIGIBLE;
+ goto out;
+ }
+
+restart_fc:
+ ret = jbd2_fc_begin_commit(journal, commit_tid);
+ if (ret == -EALREADY) {
+ /* There was an ongoing commit, check if we need to restart */
+ if (atomic_read(&sbi->s_fc_subtid) <= subtid &&
+ commit_tid > journal->j_commit_sequence)
+ goto restart_fc;
+ reason = EXT4_FC_REASON_ALREADY_COMMITTED;
+ goto out;
+ } else if (ret) {
+ sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
+ reason = EXT4_FC_REASON_FC_START_FAILED;
+ goto out;
+ }
+
+ fc_bufs_before = (sbi->s_fc_bytes + bsize - 1) / bsize;
+ ret = ext4_fc_perform_commit(journal);
+ if (ret < 0) {
+ sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
+ reason = EXT4_FC_REASON_FC_FAILED;
+ goto out;
+ }
+ nblks = (sbi->s_fc_bytes + bsize - 1) / bsize - fc_bufs_before;
+ ret = jbd2_fc_wait_bufs(journal, nblks);
+ if (ret < 0) {
+ sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
+ reason = EXT4_FC_REASON_FC_FAILED;
+ goto out;
+ }
+ atomic_inc(&sbi->s_fc_subtid);
+ jbd2_fc_end_commit(journal);
+out:
+ /* Has any ineligible update happened since we started? */
+ if (reason == EXT4_FC_REASON_OK && ext4_fc_is_ineligible(sb)) {
+ sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++;
+ reason = EXT4_FC_REASON_INELIGIBLE;
+ }
+
+ spin_lock(&sbi->s_fc_lock);
+ if (reason != EXT4_FC_REASON_OK &&
+ reason != EXT4_FC_REASON_ALREADY_COMMITTED) {
+ sbi->s_fc_stats.fc_ineligible_commits++;
+ } else {
+ sbi->s_fc_stats.fc_num_commits++;
+ sbi->s_fc_stats.fc_numblks += nblks;
+ }
+ spin_unlock(&sbi->s_fc_lock);
+ nblks = (reason == EXT4_FC_REASON_OK) ? nblks : 0;
+ trace_ext4_fc_commit_stop(sb, nblks, reason);
+ commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
+ /*
+ * weight the commit time higher than the average time so we don't
+ * react too strongly to vast changes in the commit time
+ */
+ if (likely(sbi->s_fc_avg_commit_time))
+ sbi->s_fc_avg_commit_time = (commit_time +
+ sbi->s_fc_avg_commit_time * 3) / 4;
+ else
+ sbi->s_fc_avg_commit_time = commit_time;
+ jbd_debug(1,
+ "Fast commit ended with blks = %d, reason = %d, subtid - %d",
+ nblks, reason, subtid);
+ if (reason == EXT4_FC_REASON_FC_FAILED)
+ return jbd2_fc_end_commit_fallback(journal);
+ if (reason == EXT4_FC_REASON_FC_START_FAILED ||
+ reason == EXT4_FC_REASON_INELIGIBLE)
+ return jbd2_complete_transaction(journal, commit_tid);
+ return 0;
+}
+
+/*
+ * Fast commit cleanup routine. This is called after every fast commit and
+ * full commit. full is true if we are called after a full commit.
+ */
+static void ext4_fc_cleanup(journal_t *journal, int full)
+{
+ struct super_block *sb = journal->j_private;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_inode_info *iter;
+ struct ext4_fc_dentry_update *fc_dentry;
+ struct list_head *pos, *n;
+
+ if (full && sbi->s_fc_bh)
+ sbi->s_fc_bh = NULL;
+
+ jbd2_fc_release_bufs(journal);
+
+ spin_lock(&sbi->s_fc_lock);
+ list_for_each_safe(pos, n, &sbi->s_fc_q[FC_Q_MAIN]) {
+ iter = list_entry(pos, struct ext4_inode_info, i_fc_list);
+ list_del_init(&iter->i_fc_list);
+ ext4_clear_inode_state(&iter->vfs_inode,
+ EXT4_STATE_FC_COMMITTING);
+ ext4_fc_reset_inode(&iter->vfs_inode);
+ /* Make sure EXT4_STATE_FC_COMMITTING bit is clear */
+ smp_mb();
+#if (BITS_PER_LONG < 64)
+ wake_up_bit(&iter->i_state_flags, EXT4_STATE_FC_COMMITTING);
+#else
+ wake_up_bit(&iter->i_flags, EXT4_STATE_FC_COMMITTING);
+#endif
+ }
+
+ while (!list_empty(&sbi->s_fc_dentry_q[FC_Q_MAIN])) {
+ fc_dentry = list_first_entry(&sbi->s_fc_dentry_q[FC_Q_MAIN],
+ struct ext4_fc_dentry_update,
+ fcd_list);
+ list_del_init(&fc_dentry->fcd_list);
+ spin_unlock(&sbi->s_fc_lock);
+
+ if (fc_dentry->fcd_name.name &&
+ fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
+ kfree(fc_dentry->fcd_name.name);
+ kmem_cache_free(ext4_fc_dentry_cachep, fc_dentry);
+ spin_lock(&sbi->s_fc_lock);
+ }
+
+ list_splice_init(&sbi->s_fc_dentry_q[FC_Q_STAGING],
+ &sbi->s_fc_dentry_q[FC_Q_MAIN]);
+ list_splice_init(&sbi->s_fc_q[FC_Q_STAGING],
+ &sbi->s_fc_q[FC_Q_MAIN]);
+
+ ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
+ ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
+
+ if (full)
+ sbi->s_fc_bytes = 0;
+ spin_unlock(&sbi->s_fc_lock);
+ trace_ext4_fc_stats(sb);
+}
+
+/* Ext4 Replay Path Routines */
+
+/* Helper struct for dentry replay routines */
+struct dentry_info_args {
+ int parent_ino, dname_len, ino, inode_len;
+ char *dname;
+};
+
+static inline void tl_to_darg(struct dentry_info_args *darg,
+ struct ext4_fc_tl *tl, u8 *val)
+{
+ struct ext4_fc_dentry_info fcd;
+
+ memcpy(&fcd, val, sizeof(fcd));
+
+ darg->parent_ino = le32_to_cpu(fcd.fc_parent_ino);
+ darg->ino = le32_to_cpu(fcd.fc_ino);
+ darg->dname = val + offsetof(struct ext4_fc_dentry_info, fc_dname);
+ darg->dname_len = le16_to_cpu(tl->fc_len) -
+ sizeof(struct ext4_fc_dentry_info);
+}
+
+/* Unlink replay function */
+static int ext4_fc_replay_unlink(struct super_block *sb, struct ext4_fc_tl *tl,
+ u8 *val)
+{
+ struct inode *inode, *old_parent;
+ struct qstr entry;
+ struct dentry_info_args darg;
+ int ret = 0;
+
+ tl_to_darg(&darg, tl, val);
+
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_UNLINK, darg.ino,
+ darg.parent_ino, darg.dname_len);
+
+ entry.name = darg.dname;
+ entry.len = darg.dname_len;
+ inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
+
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode %d not found", darg.ino);
+ return 0;
+ }
+
+ old_parent = ext4_iget(sb, darg.parent_ino,
+ EXT4_IGET_NORMAL);
+ if (IS_ERR(old_parent)) {
+ jbd_debug(1, "Dir with inode %d not found", darg.parent_ino);
+ iput(inode);
+ return 0;
+ }
+
+ ret = __ext4_unlink(NULL, old_parent, &entry, inode);
+ /* -ENOENT ok coz it might not exist anymore. */
+ if (ret == -ENOENT)
+ ret = 0;
+ iput(old_parent);
+ iput(inode);
+ return ret;
+}
+
+static int ext4_fc_replay_link_internal(struct super_block *sb,
+ struct dentry_info_args *darg,
+ struct inode *inode)
+{
+ struct inode *dir = NULL;
+ struct dentry *dentry_dir = NULL, *dentry_inode = NULL;
+ struct qstr qstr_dname = QSTR_INIT(darg->dname, darg->dname_len);
+ int ret = 0;
+
+ dir = ext4_iget(sb, darg->parent_ino, EXT4_IGET_NORMAL);
+ if (IS_ERR(dir)) {
+ jbd_debug(1, "Dir with inode %d not found.", darg->parent_ino);
+ dir = NULL;
+ goto out;
+ }
+
+ dentry_dir = d_obtain_alias(dir);
+ if (IS_ERR(dentry_dir)) {
+ jbd_debug(1, "Failed to obtain dentry");
+ dentry_dir = NULL;
+ goto out;
+ }
+
+ dentry_inode = d_alloc(dentry_dir, &qstr_dname);
+ if (!dentry_inode) {
+ jbd_debug(1, "Inode dentry not created.");
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = __ext4_link(dir, inode, dentry_inode);
+ /*
+ * It's possible that link already existed since data blocks
+ * for the dir in question got persisted before we crashed OR
+ * we replayed this tag and crashed before the entire replay
+ * could complete.
+ */
+ if (ret && ret != -EEXIST) {
+ jbd_debug(1, "Failed to link\n");
+ goto out;
+ }
+
+ ret = 0;
+out:
+ if (dentry_dir) {
+ d_drop(dentry_dir);
+ dput(dentry_dir);
+ } else if (dir) {
+ iput(dir);
+ }
+ if (dentry_inode) {
+ d_drop(dentry_inode);
+ dput(dentry_inode);
+ }
+
+ return ret;
+}
+
+/* Link replay function */
+static int ext4_fc_replay_link(struct super_block *sb, struct ext4_fc_tl *tl,
+ u8 *val)
+{
+ struct inode *inode;
+ struct dentry_info_args darg;
+ int ret = 0;
+
+ tl_to_darg(&darg, tl, val);
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_LINK, darg.ino,
+ darg.parent_ino, darg.dname_len);
+
+ inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode not found.");
+ return 0;
+ }
+
+ ret = ext4_fc_replay_link_internal(sb, &darg, inode);
+ iput(inode);
+ return ret;
+}
+
+/*
+ * Record all the modified inodes during replay. We use this later to setup
+ * block bitmaps correctly.
+ */
+static int ext4_fc_record_modified_inode(struct super_block *sb, int ino)
+{
+ struct ext4_fc_replay_state *state;
+ int i;
+
+ state = &EXT4_SB(sb)->s_fc_replay_state;
+ for (i = 0; i < state->fc_modified_inodes_used; i++)
+ if (state->fc_modified_inodes[i] == ino)
+ return 0;
+ if (state->fc_modified_inodes_used == state->fc_modified_inodes_size) {
+ state->fc_modified_inodes = krealloc(
+ state->fc_modified_inodes,
+ sizeof(int) * (state->fc_modified_inodes_size +
+ EXT4_FC_REPLAY_REALLOC_INCREMENT),
+ GFP_KERNEL);
+ if (!state->fc_modified_inodes)
+ return -ENOMEM;
+ state->fc_modified_inodes_size +=
+ EXT4_FC_REPLAY_REALLOC_INCREMENT;
+ }
+ state->fc_modified_inodes[state->fc_modified_inodes_used++] = ino;
+ return 0;
+}
+
+/*
+ * Inode replay function
+ */
+static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl,
+ u8 *val)
+{
+ struct ext4_fc_inode fc_inode;
+ struct ext4_inode *raw_inode;
+ struct ext4_inode *raw_fc_inode;
+ struct inode *inode = NULL;
+ struct ext4_iloc iloc;
+ int inode_len, ino, ret, tag = le16_to_cpu(tl->fc_tag);
+ struct ext4_extent_header *eh;
+
+ memcpy(&fc_inode, val, sizeof(fc_inode));
+
+ ino = le32_to_cpu(fc_inode.fc_ino);
+ trace_ext4_fc_replay(sb, tag, ino, 0, 0);
+
+ inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
+ if (!IS_ERR(inode)) {
+ ext4_ext_clear_bb(inode);
+ iput(inode);
+ }
+ inode = NULL;
+
+ ret = ext4_fc_record_modified_inode(sb, ino);
+ if (ret)
+ goto out;
+
+ raw_fc_inode = (struct ext4_inode *)
+ (val + offsetof(struct ext4_fc_inode, fc_raw_inode));
+ ret = ext4_get_fc_inode_loc(sb, ino, &iloc);
+ if (ret)
+ goto out;
+
+ inode_len = le16_to_cpu(tl->fc_len) - sizeof(struct ext4_fc_inode);
+ raw_inode = ext4_raw_inode(&iloc);
+
+ memcpy(raw_inode, raw_fc_inode, offsetof(struct ext4_inode, i_block));
+ memcpy(&raw_inode->i_generation, &raw_fc_inode->i_generation,
+ inode_len - offsetof(struct ext4_inode, i_generation));
+ if (le32_to_cpu(raw_inode->i_flags) & EXT4_EXTENTS_FL) {
+ eh = (struct ext4_extent_header *)(&raw_inode->i_block[0]);
+ if (eh->eh_magic != EXT4_EXT_MAGIC) {
+ memset(eh, 0, sizeof(*eh));
+ eh->eh_magic = EXT4_EXT_MAGIC;
+ eh->eh_max = cpu_to_le16(
+ (sizeof(raw_inode->i_block) -
+ sizeof(struct ext4_extent_header))
+ / sizeof(struct ext4_extent));
+ }
+ } else if (le32_to_cpu(raw_inode->i_flags) & EXT4_INLINE_DATA_FL) {
+ memcpy(raw_inode->i_block, raw_fc_inode->i_block,
+ sizeof(raw_inode->i_block));
+ }
+
+ /* Immediately update the inode on disk. */
+ ret = ext4_handle_dirty_metadata(NULL, NULL, iloc.bh);
+ if (ret)
+ goto out;
+ ret = sync_dirty_buffer(iloc.bh);
+ if (ret)
+ goto out;
+ ret = ext4_mark_inode_used(sb, ino);
+ if (ret)
+ goto out;
+
+ /* Given that we just wrote the inode on disk, this SHOULD succeed. */
+ inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode not found.");
+ return -EFSCORRUPTED;
+ }
+
+ /*
+ * Our allocator could have made different decisions than before
+ * crashing. This should be fixed but until then, we calculate
+ * the number of blocks the inode.
+ */
+ ext4_ext_replay_set_iblocks(inode);
+
+ inode->i_generation = le32_to_cpu(ext4_raw_inode(&iloc)->i_generation);
+ ext4_reset_inode_seed(inode);
+
+ ext4_inode_csum_set(inode, ext4_raw_inode(&iloc), EXT4_I(inode));
+ ret = ext4_handle_dirty_metadata(NULL, NULL, iloc.bh);
+ sync_dirty_buffer(iloc.bh);
+ brelse(iloc.bh);
+out:
+ iput(inode);
+ if (!ret)
+ blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
+
+ return 0;
+}
+
+/*
+ * Dentry create replay function.
+ *
+ * EXT4_FC_TAG_CREAT is preceded by EXT4_FC_TAG_INODE_FULL. Which means, the
+ * inode for which we are trying to create a dentry here, should already have
+ * been replayed before we start here.
+ */
+static int ext4_fc_replay_create(struct super_block *sb, struct ext4_fc_tl *tl,
+ u8 *val)
+{
+ int ret = 0;
+ struct inode *inode = NULL;
+ struct inode *dir = NULL;
+ struct dentry_info_args darg;
+
+ tl_to_darg(&darg, tl, val);
+
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_CREAT, darg.ino,
+ darg.parent_ino, darg.dname_len);
+
+ /* This takes care of update group descriptor and other metadata */
+ ret = ext4_mark_inode_used(sb, darg.ino);
+ if (ret)
+ goto out;
+
+ inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "inode %d not found.", darg.ino);
+ inode = NULL;
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (S_ISDIR(inode->i_mode)) {
+ /*
+ * If we are creating a directory, we need to make sure that the
+ * dot and dot dot dirents are setup properly.
+ */
+ dir = ext4_iget(sb, darg.parent_ino, EXT4_IGET_NORMAL);
+ if (IS_ERR(dir)) {
+ jbd_debug(1, "Dir %d not found.", darg.ino);
+ goto out;
+ }
+ ret = ext4_init_new_dir(NULL, dir, inode);
+ iput(dir);
+ if (ret) {
+ ret = 0;
+ goto out;
+ }
+ }
+ ret = ext4_fc_replay_link_internal(sb, &darg, inode);
+ if (ret)
+ goto out;
+ set_nlink(inode, 1);
+ ext4_mark_inode_dirty(NULL, inode);
+out:
+ if (inode)
+ iput(inode);
+ return ret;
+}
+
+/*
+ * Record physical disk regions which are in use as per fast commit area,
+ * and used by inodes during replay phase. Our simple replay phase
+ * allocator excludes these regions from allocation.
+ */
+int ext4_fc_record_regions(struct super_block *sb, int ino,
+ ext4_lblk_t lblk, ext4_fsblk_t pblk, int len, int replay)
+{
+ struct ext4_fc_replay_state *state;
+ struct ext4_fc_alloc_region *region;
+
+ state = &EXT4_SB(sb)->s_fc_replay_state;
+ /*
+ * during replay phase, the fc_regions_valid may not same as
+ * fc_regions_used, update it when do new additions.
+ */
+ if (replay && state->fc_regions_used != state->fc_regions_valid)
+ state->fc_regions_used = state->fc_regions_valid;
+ if (state->fc_regions_used == state->fc_regions_size) {
+ state->fc_regions_size +=
+ EXT4_FC_REPLAY_REALLOC_INCREMENT;
+ state->fc_regions = krealloc(
+ state->fc_regions,
+ state->fc_regions_size *
+ sizeof(struct ext4_fc_alloc_region),
+ GFP_KERNEL);
+ if (!state->fc_regions)
+ return -ENOMEM;
+ }
+ region = &state->fc_regions[state->fc_regions_used++];
+ region->ino = ino;
+ region->lblk = lblk;
+ region->pblk = pblk;
+ region->len = len;
+
+ if (replay)
+ state->fc_regions_valid++;
+
+ return 0;
+}
+
+/* Replay add range tag */
+static int ext4_fc_replay_add_range(struct super_block *sb,
+ struct ext4_fc_tl *tl, u8 *val)
+{
+ struct ext4_fc_add_range fc_add_ex;
+ struct ext4_extent newex, *ex;
+ struct inode *inode;
+ ext4_lblk_t start, cur;
+ int remaining, len;
+ ext4_fsblk_t start_pblk;
+ struct ext4_map_blocks map;
+ struct ext4_ext_path *path = NULL;
+ int ret;
+
+ memcpy(&fc_add_ex, val, sizeof(fc_add_ex));
+ ex = (struct ext4_extent *)&fc_add_ex.fc_ex;
+
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_ADD_RANGE,
+ le32_to_cpu(fc_add_ex.fc_ino), le32_to_cpu(ex->ee_block),
+ ext4_ext_get_actual_len(ex));
+
+ inode = ext4_iget(sb, le32_to_cpu(fc_add_ex.fc_ino), EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode not found.");
+ return 0;
+ }
+
+ ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
+ if (ret)
+ goto out;
+
+ start = le32_to_cpu(ex->ee_block);
+ start_pblk = ext4_ext_pblock(ex);
+ len = ext4_ext_get_actual_len(ex);
+
+ cur = start;
+ remaining = len;
+ jbd_debug(1, "ADD_RANGE, lblk %d, pblk %lld, len %d, unwritten %d, inode %ld\n",
+ start, start_pblk, len, ext4_ext_is_unwritten(ex),
+ inode->i_ino);
+
+ while (remaining > 0) {
+ map.m_lblk = cur;
+ map.m_len = remaining;
+ map.m_pblk = 0;
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+
+ if (ret < 0)
+ goto out;
+
+ if (ret == 0) {
+ /* Range is not mapped */
+ path = ext4_find_extent(inode, cur, NULL, 0);
+ if (IS_ERR(path))
+ goto out;
+ memset(&newex, 0, sizeof(newex));
+ newex.ee_block = cpu_to_le32(cur);
+ ext4_ext_store_pblock(
+ &newex, start_pblk + cur - start);
+ newex.ee_len = cpu_to_le16(map.m_len);
+ if (ext4_ext_is_unwritten(ex))
+ ext4_ext_mark_unwritten(&newex);
+ down_write(&EXT4_I(inode)->i_data_sem);
+ ret = ext4_ext_insert_extent(
+ NULL, inode, &path, &newex, 0);
+ up_write((&EXT4_I(inode)->i_data_sem));
+ ext4_ext_drop_refs(path);
+ kfree(path);
+ if (ret)
+ goto out;
+ goto next;
+ }
+
+ if (start_pblk + cur - start != map.m_pblk) {
+ /*
+ * Logical to physical mapping changed. This can happen
+ * if this range was removed and then reallocated to
+ * map to new physical blocks during a fast commit.
+ */
+ ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
+ ext4_ext_is_unwritten(ex),
+ start_pblk + cur - start);
+ if (ret)
+ goto out;
+ /*
+ * Mark the old blocks as free since they aren't used
+ * anymore. We maintain an array of all the modified
+ * inodes. In case these blocks are still used at either
+ * a different logical range in the same inode or in
+ * some different inode, we will mark them as allocated
+ * at the end of the FC replay using our array of
+ * modified inodes.
+ */
+ ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0);
+ goto next;
+ }
+
+ /* Range is mapped and needs a state change */
+ jbd_debug(1, "Converting from %ld to %d %lld",
+ map.m_flags & EXT4_MAP_UNWRITTEN,
+ ext4_ext_is_unwritten(ex), map.m_pblk);
+ ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
+ ext4_ext_is_unwritten(ex), map.m_pblk);
+ if (ret)
+ goto out;
+ /*
+ * We may have split the extent tree while toggling the state.
+ * Try to shrink the extent tree now.
+ */
+ ext4_ext_replay_shrink_inode(inode, start + len);
+next:
+ cur += map.m_len;
+ remaining -= map.m_len;
+ }
+ ext4_ext_replay_shrink_inode(inode, i_size_read(inode) >>
+ sb->s_blocksize_bits);
+out:
+ iput(inode);
+ return 0;
+}
+
+/* Replay DEL_RANGE tag */
+static int
+ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl,
+ u8 *val)
+{
+ struct inode *inode;
+ struct ext4_fc_del_range lrange;
+ struct ext4_map_blocks map;
+ ext4_lblk_t cur, remaining;
+ int ret;
+
+ memcpy(&lrange, val, sizeof(lrange));
+ cur = le32_to_cpu(lrange.fc_lblk);
+ remaining = le32_to_cpu(lrange.fc_len);
+
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_DEL_RANGE,
+ le32_to_cpu(lrange.fc_ino), cur, remaining);
+
+ inode = ext4_iget(sb, le32_to_cpu(lrange.fc_ino), EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode %d not found", le32_to_cpu(lrange.fc_ino));
+ return 0;
+ }
+
+ ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
+ if (ret)
+ goto out;
+
+ jbd_debug(1, "DEL_RANGE, inode %ld, lblk %d, len %d\n",
+ inode->i_ino, le32_to_cpu(lrange.fc_lblk),
+ le32_to_cpu(lrange.fc_len));
+ while (remaining > 0) {
+ map.m_lblk = cur;
+ map.m_len = remaining;
+
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ remaining -= ret;
+ cur += ret;
+ ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0);
+ } else {
+ remaining -= map.m_len;
+ cur += map.m_len;
+ }
+ }
+
+ down_write(&EXT4_I(inode)->i_data_sem);
+ ret = ext4_ext_remove_space(inode, le32_to_cpu(lrange.fc_lblk),
+ le32_to_cpu(lrange.fc_lblk) +
+ le32_to_cpu(lrange.fc_len) - 1);
+ up_write(&EXT4_I(inode)->i_data_sem);
+ if (ret)
+ goto out;
+ ext4_ext_replay_shrink_inode(inode,
+ i_size_read(inode) >> sb->s_blocksize_bits);
+ ext4_mark_inode_dirty(NULL, inode);
+out:
+ iput(inode);
+ return 0;
+}
+
+static inline const char *tag2str(u16 tag)
+{
+ switch (tag) {
+ case EXT4_FC_TAG_LINK:
+ return "TAG_ADD_ENTRY";
+ case EXT4_FC_TAG_UNLINK:
+ return "TAG_DEL_ENTRY";
+ case EXT4_FC_TAG_ADD_RANGE:
+ return "TAG_ADD_RANGE";
+ case EXT4_FC_TAG_CREAT:
+ return "TAG_CREAT_DENTRY";
+ case EXT4_FC_TAG_DEL_RANGE:
+ return "TAG_DEL_RANGE";
+ case EXT4_FC_TAG_INODE:
+ return "TAG_INODE";
+ case EXT4_FC_TAG_PAD:
+ return "TAG_PAD";
+ case EXT4_FC_TAG_TAIL:
+ return "TAG_TAIL";
+ case EXT4_FC_TAG_HEAD:
+ return "TAG_HEAD";
+ default:
+ return "TAG_ERROR";
+ }
+}
+
+static void ext4_fc_set_bitmaps_and_counters(struct super_block *sb)
+{
+ struct ext4_fc_replay_state *state;
+ struct inode *inode;
+ struct ext4_ext_path *path = NULL;
+ struct ext4_map_blocks map;
+ int i, ret, j;
+ ext4_lblk_t cur, end;
+
+ state = &EXT4_SB(sb)->s_fc_replay_state;
+ for (i = 0; i < state->fc_modified_inodes_used; i++) {
+ inode = ext4_iget(sb, state->fc_modified_inodes[i],
+ EXT4_IGET_NORMAL);
+ if (IS_ERR(inode)) {
+ jbd_debug(1, "Inode %d not found.",
+ state->fc_modified_inodes[i]);
+ continue;
+ }
+ cur = 0;
+ end = EXT_MAX_BLOCKS;
+ while (cur < end) {
+ map.m_lblk = cur;
+ map.m_len = end - cur;
+
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret < 0)
+ break;
+
+ if (ret > 0) {
+ path = ext4_find_extent(inode, map.m_lblk, NULL, 0);
+ if (!IS_ERR(path)) {
+ for (j = 0; j < path->p_depth; j++)
+ ext4_mb_mark_bb(inode->i_sb,
+ path[j].p_block, 1, 1);
+ ext4_ext_drop_refs(path);
+ kfree(path);
+ }
+ cur += ret;
+ ext4_mb_mark_bb(inode->i_sb, map.m_pblk,
+ map.m_len, 1);
+ } else {
+ cur = cur + (map.m_len ? map.m_len : 1);
+ }
+ }
+ iput(inode);
+ }
+}
+
+/*
+ * Check if block is in excluded regions for block allocation. The simple
+ * allocator that runs during replay phase is calls this function to see
+ * if it is okay to use a block.
+ */
+bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t blk)
+{
+ int i;
+ struct ext4_fc_replay_state *state;
+
+ state = &EXT4_SB(sb)->s_fc_replay_state;
+ for (i = 0; i < state->fc_regions_valid; i++) {
+ if (state->fc_regions[i].ino == 0 ||
+ state->fc_regions[i].len == 0)
+ continue;
+ if (blk >= state->fc_regions[i].pblk &&
+ blk < state->fc_regions[i].pblk + state->fc_regions[i].len)
+ return true;
+ }
+ return false;
+}
+
+/* Cleanup function called after replay */
+void ext4_fc_replay_cleanup(struct super_block *sb)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ sbi->s_mount_state &= ~EXT4_FC_REPLAY;
+ kfree(sbi->s_fc_replay_state.fc_regions);
+ kfree(sbi->s_fc_replay_state.fc_modified_inodes);
+}
+
+/*
+ * Recovery Scan phase handler
+ *
+ * This function is called during the scan phase and is responsible
+ * for doing following things:
+ * - Make sure the fast commit area has valid tags for replay
+ * - Count number of tags that need to be replayed by the replay handler
+ * - Verify CRC
+ * - Create a list of excluded blocks for allocation during replay phase
+ *
+ * This function returns JBD2_FC_REPLAY_CONTINUE to indicate that SCAN is
+ * incomplete and JBD2 should send more blocks. It returns JBD2_FC_REPLAY_STOP
+ * to indicate that scan has finished and JBD2 can now start replay phase.
+ * It returns a negative error to indicate that there was an error. At the end
+ * of a successful scan phase, sbi->s_fc_replay_state.fc_replay_num_tags is set
+ * to indicate the number of tags that need to replayed during the replay phase.
+ */
+static int ext4_fc_replay_scan(journal_t *journal,
+ struct buffer_head *bh, int off,
+ tid_t expected_tid)
+{
+ struct super_block *sb = journal->j_private;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_fc_replay_state *state;
+ int ret = JBD2_FC_REPLAY_CONTINUE;
+ struct ext4_fc_add_range ext;
+ struct ext4_fc_tl tl;
+ struct ext4_fc_tail tail;
+ __u8 *start, *end, *cur, *val;
+ struct ext4_fc_head head;
+ struct ext4_extent *ex;
+
+ state = &sbi->s_fc_replay_state;
+
+ start = (u8 *)bh->b_data;
+ end = (__u8 *)bh->b_data + journal->j_blocksize - 1;
+
+ if (state->fc_replay_expected_off == 0) {
+ state->fc_cur_tag = 0;
+ state->fc_replay_num_tags = 0;
+ state->fc_crc = 0;
+ state->fc_regions = NULL;
+ state->fc_regions_valid = state->fc_regions_used =
+ state->fc_regions_size = 0;
+ /* Check if we can stop early */
+ if (le16_to_cpu(((struct ext4_fc_tl *)start)->fc_tag)
+ != EXT4_FC_TAG_HEAD)
+ return 0;
+ }
+
+ if (off != state->fc_replay_expected_off) {
+ ret = -EFSCORRUPTED;
+ goto out_err;
+ }
+
+ state->fc_replay_expected_off++;
+ for (cur = start; cur < end; cur = cur + sizeof(tl) + le16_to_cpu(tl.fc_len)) {
+ memcpy(&tl, cur, sizeof(tl));
+ val = cur + sizeof(tl);
+ jbd_debug(3, "Scan phase, tag:%s, blk %lld\n",
+ tag2str(le16_to_cpu(tl.fc_tag)), bh->b_blocknr);
+ switch (le16_to_cpu(tl.fc_tag)) {
+ case EXT4_FC_TAG_ADD_RANGE:
+ memcpy(&ext, val, sizeof(ext));
+ ex = (struct ext4_extent *)&ext.fc_ex;
+ ret = ext4_fc_record_regions(sb,
+ le32_to_cpu(ext.fc_ino),
+ le32_to_cpu(ex->ee_block), ext4_ext_pblock(ex),
+ ext4_ext_get_actual_len(ex), 0);
+ if (ret < 0)
+ break;
+ ret = JBD2_FC_REPLAY_CONTINUE;
+ fallthrough;
+ case EXT4_FC_TAG_DEL_RANGE:
+ case EXT4_FC_TAG_LINK:
+ case EXT4_FC_TAG_UNLINK:
+ case EXT4_FC_TAG_CREAT:
+ case EXT4_FC_TAG_INODE:
+ case EXT4_FC_TAG_PAD:
+ state->fc_cur_tag++;
+ state->fc_crc = ext4_chksum(sbi, state->fc_crc, cur,
+ sizeof(tl) + le16_to_cpu(tl.fc_len));
+ break;
+ case EXT4_FC_TAG_TAIL:
+ state->fc_cur_tag++;
+ memcpy(&tail, val, sizeof(tail));
+ state->fc_crc = ext4_chksum(sbi, state->fc_crc, cur,
+ sizeof(tl) +
+ offsetof(struct ext4_fc_tail,
+ fc_crc));
+ if (le32_to_cpu(tail.fc_tid) == expected_tid &&
+ le32_to_cpu(tail.fc_crc) == state->fc_crc) {
+ state->fc_replay_num_tags = state->fc_cur_tag;
+ state->fc_regions_valid =
+ state->fc_regions_used;
+ } else {
+ ret = state->fc_replay_num_tags ?
+ JBD2_FC_REPLAY_STOP : -EFSBADCRC;
+ }
+ state->fc_crc = 0;
+ break;
+ case EXT4_FC_TAG_HEAD:
+ memcpy(&head, val, sizeof(head));
+ if (le32_to_cpu(head.fc_features) &
+ ~EXT4_FC_SUPPORTED_FEATURES) {
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ if (le32_to_cpu(head.fc_tid) != expected_tid) {
+ ret = JBD2_FC_REPLAY_STOP;
+ break;
+ }
+ state->fc_cur_tag++;
+ state->fc_crc = ext4_chksum(sbi, state->fc_crc, cur,
+ sizeof(tl) + le16_to_cpu(tl.fc_len));
+ break;
+ default:
+ ret = state->fc_replay_num_tags ?
+ JBD2_FC_REPLAY_STOP : -ECANCELED;
+ }
+ if (ret < 0 || ret == JBD2_FC_REPLAY_STOP)
+ break;
+ }
+
+out_err:
+ trace_ext4_fc_replay_scan(sb, ret, off);
+ return ret;
+}
+
+/*
+ * Main recovery path entry point.
+ * The meaning of return codes is similar as above.
+ */
+static int ext4_fc_replay(journal_t *journal, struct buffer_head *bh,
+ enum passtype pass, int off, tid_t expected_tid)
+{
+ struct super_block *sb = journal->j_private;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_fc_tl tl;
+ __u8 *start, *end, *cur, *val;
+ int ret = JBD2_FC_REPLAY_CONTINUE;
+ struct ext4_fc_replay_state *state = &sbi->s_fc_replay_state;
+ struct ext4_fc_tail tail;
+
+ if (pass == PASS_SCAN) {
+ state->fc_current_pass = PASS_SCAN;
+ return ext4_fc_replay_scan(journal, bh, off, expected_tid);
+ }
+
+ if (state->fc_current_pass != pass) {
+ state->fc_current_pass = pass;
+ sbi->s_mount_state |= EXT4_FC_REPLAY;
+ }
+ if (!sbi->s_fc_replay_state.fc_replay_num_tags) {
+ jbd_debug(1, "Replay stops\n");
+ ext4_fc_set_bitmaps_and_counters(sb);
+ return 0;
+ }
+
+#ifdef CONFIG_EXT4_DEBUG
+ if (sbi->s_fc_debug_max_replay && off >= sbi->s_fc_debug_max_replay) {
+ pr_warn("Dropping fc block %d because max_replay set\n", off);
+ return JBD2_FC_REPLAY_STOP;
+ }
+#endif
+
+ start = (u8 *)bh->b_data;
+ end = (__u8 *)bh->b_data + journal->j_blocksize - 1;
+
+ for (cur = start; cur < end; cur = cur + sizeof(tl) + le16_to_cpu(tl.fc_len)) {
+ memcpy(&tl, cur, sizeof(tl));
+ val = cur + sizeof(tl);
+
+ if (state->fc_replay_num_tags == 0) {
+ ret = JBD2_FC_REPLAY_STOP;
+ ext4_fc_set_bitmaps_and_counters(sb);
+ break;
+ }
+ jbd_debug(3, "Replay phase, tag:%s\n",
+ tag2str(le16_to_cpu(tl.fc_tag)));
+ state->fc_replay_num_tags--;
+ switch (le16_to_cpu(tl.fc_tag)) {
+ case EXT4_FC_TAG_LINK:
+ ret = ext4_fc_replay_link(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_UNLINK:
+ ret = ext4_fc_replay_unlink(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_ADD_RANGE:
+ ret = ext4_fc_replay_add_range(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_CREAT:
+ ret = ext4_fc_replay_create(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_DEL_RANGE:
+ ret = ext4_fc_replay_del_range(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_INODE:
+ ret = ext4_fc_replay_inode(sb, &tl, val);
+ break;
+ case EXT4_FC_TAG_PAD:
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_PAD, 0,
+ le16_to_cpu(tl.fc_len), 0);
+ break;
+ case EXT4_FC_TAG_TAIL:
+ trace_ext4_fc_replay(sb, EXT4_FC_TAG_TAIL, 0,
+ le16_to_cpu(tl.fc_len), 0);
+ memcpy(&tail, val, sizeof(tail));
+ WARN_ON(le32_to_cpu(tail.fc_tid) != expected_tid);
+ break;
+ case EXT4_FC_TAG_HEAD:
+ break;
+ default:
+ trace_ext4_fc_replay(sb, le16_to_cpu(tl.fc_tag), 0,
+ le16_to_cpu(tl.fc_len), 0);
+ ret = -ECANCELED;
+ break;
+ }
+ if (ret < 0)
+ break;
+ ret = JBD2_FC_REPLAY_CONTINUE;
+ }
+ return ret;
+}
+
+void ext4_fc_init(struct super_block *sb, journal_t *journal)
+{
+ /*
+ * We set replay callback even if fast commit disabled because we may
+ * could still have fast commit blocks that need to be replayed even if
+ * fast commit has now been turned off.
+ */
+ journal->j_fc_replay_callback = ext4_fc_replay;
+ if (!test_opt2(sb, JOURNAL_FAST_COMMIT))
+ return;
+ journal->j_fc_cleanup_callback = ext4_fc_cleanup;
+}
+
+static const char *fc_ineligible_reasons[] = {
+ "Extended attributes changed",
+ "Cross rename",
+ "Journal flag changed",
+ "Insufficient memory",
+ "Swap boot",
+ "Resize",
+ "Dir renamed",
+ "Falloc range op",
+ "Data journalling",
+ "FC Commit Failed"
+};
+
+int ext4_fc_info_show(struct seq_file *seq, void *v)
+{
+ struct ext4_sb_info *sbi = EXT4_SB((struct super_block *)seq->private);
+ struct ext4_fc_stats *stats = &sbi->s_fc_stats;
+ int i;
+
+ if (v != SEQ_START_TOKEN)
+ return 0;
+
+ seq_printf(seq,
+ "fc stats:\n%ld commits\n%ld ineligible\n%ld numblks\n%lluus avg_commit_time\n",
+ stats->fc_num_commits, stats->fc_ineligible_commits,
+ stats->fc_numblks,
+ div_u64(sbi->s_fc_avg_commit_time, 1000));
+ seq_puts(seq, "Ineligible reasons:\n");
+ for (i = 0; i < EXT4_FC_REASON_MAX; i++)
+ seq_printf(seq, "\"%s\":\t%d\n", fc_ineligible_reasons[i],
+ stats->fc_ineligible_reason_count[i]);
+
+ return 0;
+}
+
+int __init ext4_fc_init_dentry_cache(void)
+{
+ ext4_fc_dentry_cachep = KMEM_CACHE(ext4_fc_dentry_update,
+ SLAB_RECLAIM_ACCOUNT);
+
+ if (ext4_fc_dentry_cachep == NULL)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void ext4_fc_destroy_dentry_cache(void)
+{
+ kmem_cache_destroy(ext4_fc_dentry_cachep);
+}