[PATCH 5.15 099/110] ext4: prevent used blocks from being allocated during fast commit replay

Greg Kroah-Hartman
2022-02-07T12:03:19Z

From: Xin Yin <yinxin.x@bytedance.com>

commit 599ea31d13617c5484c40cdf50d88301dc351cfc upstream.

During fast commit replay procedure, we clear inode blocks bitmap in
ext4_ext_clear_bb(), this may cause ext4_mb_new_blocks_simple() allocate
blocks still in use.

Make ext4_fc_record_regions() also record physical disk regions used by
inodes during replay procedure. Then ext4_mb_new_blocks_simple() can
excludes these blocks in use.

Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Link: https://lore.kernel.org/r/20220110035141.1980-2-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext4/ext4.h | 3 +++
fs/ext4/extents.c | 4 ++++
fs/ext4/fast_commit.c | 20 +++++++++++++++-----
3 files changed, 22 insertions(+), 5 deletions(-)

--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2935,6 +2935,9 @@ void ext4_fc_replay_cleanup(struct super
int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
int __init ext4_fc_init_dentry_cache(void);
void ext4_fc_destroy_dentry_cache(void);
+int ext4_fc_record_regions(struct super_block *sb, int ino,
+ ext4_lblk_t lblk, ext4_fsblk_t pblk,
+ int len, int replay);

/* mballoc.c */
extern const struct seq_operations ext4_mb_seq_groups_ops;
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -6096,11 +6096,15 @@ int ext4_ext_clear_bb(struct inode *inod

ext4_mb_mark_bb(inode->i_sb,
path[j].p_block, 1, 0);
+ ext4_fc_record_regions(inode->i_sb, inode->i_ino,
+ 0, path[j].p_block, 1, 1);
}
ext4_ext_drop_refs(path);
kfree(path);
}
ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0);
+ ext4_fc_record_regions(inode->i_sb, inode->i_ino,
+ map.m_lblk, map.m_pblk, map.m_len, 1);
}
cur = cur + map.m_len;
}
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1603,16 +1603,23 @@ out:
}

/*
- * Record physical disk regions which are in use as per fast commit area. Our
- * simple replay phase allocator excludes these regions from allocation.
+ * 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.
*/
-static int ext4_fc_record_regions(struct super_block *sb, int ino,
- ext4_lblk_t lblk, ext4_fsblk_t pblk, int len)
+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;
@@ -1630,6 +1637,9 @@ static int ext4_fc_record_regions(struct
region->pblk = pblk;
region->len = len;

+ if (replay)
+ state->fc_regions_valid++;
+
return 0;
}

@@ -1973,7 +1983,7 @@ static int ext4_fc_replay_scan(journal_t
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));
+ ext4_ext_get_actual_len(ex), 0);
if (ret < 0)
break;
ret = JBD2_FC_REPLAY_CONTINUE;