[PATCH 6.19 15/18] Revert "f2fs: block cache/dio write during f2fs_enable_checkpoint()"

Greg Kroah-Hartman
2026-02-17T20:49:28Z

From: Chao Yu <chao@kernel.org>

[ Upstream commit 3996b70209f145bfcf2afc7d05dd92c27b233b48 ]

This reverts commit 196c81fdd438f7ac429d5639090a9816abb9760a.

Original patch may cause below deadlock, revert it.

write remount
- write_begin
- lock_page --- lock A
- prepare_write_begin
- f2fs_map_lock
- f2fs_enable_checkpoint
- down_write(cp_enable_rwsem) --- lock B
- sync_inode_sb
- writepages
- lock_page --- lock A
- down_read(cp_enable_rwsem) --- lock A

Cc: stable@kernel.org
Fixes: 196c81fdd438 ("f2fs: block cache/dio write during f2fs_enable_checkpoint()")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
[ drop tracing bits ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/f2fs/data.c | 2 --
fs/f2fs/f2fs.h | 3 +--
fs/f2fs/super.c | 38 ++++++++------------------------------
3 files changed, 9 insertions(+), 34 deletions(-)

--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1424,7 +1424,6 @@ static int __allocate_data_block(struct

static void f2fs_map_lock(struct f2fs_sb_info *sbi, int flag)
{
- f2fs_down_read(&sbi->cp_enable_rwsem);
if (flag == F2FS_GET_BLOCK_PRE_AIO)
f2fs_down_read(&sbi->node_change);
else
@@ -1437,7 +1436,6 @@ static void f2fs_map_unlock(struct f2fs_
f2fs_up_read(&sbi->node_change);
else
f2fs_unlock_op(sbi);
- f2fs_up_read(&sbi->cp_enable_rwsem);
}

int f2fs_get_block_locked(struct dnode_of_data *dn, pgoff_t index)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -287,7 +287,7 @@ enum {
#define DEF_CP_INTERVAL 60 /* 60 secs */
#define DEF_IDLE_INTERVAL 5 /* 5 secs */
#define DEF_DISABLE_INTERVAL 5 /* 5 secs */
-#define DEF_ENABLE_INTERVAL 5 /* 5 secs */
+#define DEF_ENABLE_INTERVAL 16 /* 16 secs */
#define DEF_DISABLE_QUICK_INTERVAL 1 /* 1 secs */
#define DEF_UMOUNT_DISCARD_TIMEOUT 5 /* 5 secs */

@@ -1720,7 +1720,6 @@ struct f2fs_sb_info {
long interval_time[MAX_TIME]; /* to store thresholds */
struct ckpt_req_control cprc_info; /* for checkpoint request control */
struct cp_stats cp_stats; /* for time stat of checkpoint */
- struct f2fs_rwsem cp_enable_rwsem; /* block cache/dio write */

struct inode_management im[MAX_INO_ENTRY]; /* manage inode cache */

--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2636,11 +2636,10 @@ restore_flag:
static int f2fs_enable_checkpoint(struct f2fs_sb_info *sbi)
{
unsigned int nr_pages = get_pages(sbi, F2FS_DIRTY_DATA) / 16;
- long long start, writeback, lock, sync_inode, end;
+ long long start, writeback, end;
int ret;

- f2fs_info(sbi, "%s start, meta: %lld, node: %lld, data: %lld",
- __func__,
+ f2fs_info(sbi, "f2fs_enable_checkpoint() starts, meta: %lld, node: %lld, data: %lld",
get_pages(sbi, F2FS_DIRTY_META),
get_pages(sbi, F2FS_DIRTY_NODES),
get_pages(sbi, F2FS_DIRTY_DATA));
@@ -2659,18 +2658,11 @@ static int f2fs_enable_checkpoint(struct
}
writeback = ktime_get();

- f2fs_down_write(&sbi->cp_enable_rwsem);
-
- lock = ktime_get();
-
- if (get_pages(sbi, F2FS_DIRTY_DATA))
- sync_inodes_sb(sbi->sb);
+ sync_inodes_sb(sbi->sb);

if (unlikely(get_pages(sbi, F2FS_DIRTY_DATA)))
- f2fs_warn(sbi, "%s: has some unwritten data: %lld",
- __func__, get_pages(sbi, F2FS_DIRTY_DATA));
-
- sync_inode = ktime_get();
+ f2fs_warn(sbi, "checkpoint=enable has some unwritten data: %lld",
+ get_pages(sbi, F2FS_DIRTY_DATA));

f2fs_down_write(&sbi->gc_lock);
f2fs_dirty_to_prefree(sbi);
@@ -2679,13 +2671,6 @@ static int f2fs_enable_checkpoint(struct
set_sbi_flag(sbi, SBI_IS_DIRTY);
f2fs_up_write(&sbi->gc_lock);

- f2fs_info(sbi, "%s sync_fs, meta: %lld, imeta: %lld, node: %lld, dents: %lld, qdata: %lld",
- __func__,
- get_pages(sbi, F2FS_DIRTY_META),
- get_pages(sbi, F2FS_DIRTY_IMETA),
- get_pages(sbi, F2FS_DIRTY_NODES),
- get_pages(sbi, F2FS_DIRTY_DENTS),
- get_pages(sbi, F2FS_DIRTY_QDATA));
ret = f2fs_sync_fs(sbi->sb, 1);
if (ret)
f2fs_err(sbi, "%s sync_fs failed, ret: %d", __func__, ret);
@@ -2693,17 +2678,11 @@ static int f2fs_enable_checkpoint(struct
/* Let's ensure there's no pending checkpoint anymore */
f2fs_flush_ckpt_thread(sbi);

- f2fs_up_write(&sbi->cp_enable_rwsem);
-
end = ktime_get();

- f2fs_info(sbi, "%s end, writeback:%llu, "
- "lock:%llu, sync_inode:%llu, sync_fs:%llu",
- __func__,
- ktime_ms_delta(writeback, start),
- ktime_ms_delta(lock, writeback),
- ktime_ms_delta(sync_inode, lock),
- ktime_ms_delta(end, sync_inode));
+ f2fs_info(sbi, "f2fs_enable_checkpoint() finishes, writeback:%llu, sync:%llu",
+ ktime_ms_delta(writeback, start),
+ ktime_ms_delta(end, writeback));
return ret;
}

@@ -4904,7 +4883,6 @@ try_onemore:
init_f2fs_rwsem(&sbi->node_change);
spin_lock_init(&sbi->stat_lock);
init_f2fs_rwsem(&sbi->cp_rwsem);
- init_f2fs_rwsem(&sbi->cp_enable_rwsem);
init_f2fs_rwsem(&sbi->quota_sem);
init_waitqueue_head(&sbi->cp_wait);
spin_lock_init(&sbi->error_lock);