diff options
| author | Chao Yu <chao@kernel.org> | 2024-06-25 10:32:39 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2024-07-10 22:47:57 +0000 |
| commit | f06c0f82e38bbda7264d6ef3c90045ad2810e0f3 (patch) | |
| tree | 5a3382bedf4791ec6cfc4b7ce87dba0064af2b5e /fs/f2fs/checkpoint.c | |
| parent | 54f43a10fa257ad4af02a1d157fefef6ebcfa7dc (diff) | |
f2fs: fix to update user block counts in block_operations()
Commit 59c9081bc86e ("f2fs: allow write page cache when writting cp")
allows write() to write data to page cache during checkpoint, so block
count fields like .total_valid_block_count, .alloc_valid_block_count
and .rf_node_block_count may encounter race condition as below:
CP Thread A
- write_checkpoint
- block_operations
- f2fs_down_write(&sbi->node_change)
- __prepare_cp_block
: ckpt->valid_block_count = .total_valid_block_count
- f2fs_up_write(&sbi->node_change)
- write
- f2fs_preallocate_blocks
- f2fs_map_blocks(,F2FS_GET_BLOCK_PRE_AIO)
- f2fs_map_lock
- f2fs_down_read(&sbi->node_change)
- f2fs_reserve_new_blocks
- inc_valid_block_count
: percpu_counter_add(&sbi->alloc_valid_block_count, count)
: sbi->total_valid_block_count += count
- f2fs_up_read(&sbi->node_change)
- do_checkpoint
: sbi->last_valid_block_count = sbi->total_valid_block_count
: percpu_counter_set(&sbi->alloc_valid_block_count, 0)
: percpu_counter_set(&sbi->rf_node_block_count, 0)
- fsync
- need_do_checkpoint
- f2fs_space_for_roll_forward
: alloc_valid_block_count was reset to zero,
so, it may missed last data during checkpoint
Let's change to update .total_valid_block_count, .alloc_valid_block_count
and .rf_node_block_count in block_operations(), then their access can be
protected by .node_change and .cp_rwsem lock, so that it can avoid above
race condition.
Fixes: 59c9081bc86e ("f2fs: allow write page cache when writting cp")
Cc: Yunlei He <heyunlei@oppo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/checkpoint.c')
| -rw-r--r-- | fs/f2fs/checkpoint.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 7cfe4e01dd7e..bdd96329dddd 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -1186,6 +1186,11 @@ static void __prepare_cp_block(struct f2fs_sb_info *sbi) ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi)); ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi)); ckpt->next_free_nid = cpu_to_le32(last_nid); + + /* update user_block_counts */ + sbi->last_valid_block_count = sbi->total_valid_block_count; + percpu_counter_set(&sbi->alloc_valid_block_count, 0); + percpu_counter_set(&sbi->rf_node_block_count, 0); } static bool __need_flush_quota(struct f2fs_sb_info *sbi) @@ -1575,11 +1580,6 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) start_blk += NR_CURSEG_NODE_TYPE; } - /* update user_block_counts */ - sbi->last_valid_block_count = sbi->total_valid_block_count; - percpu_counter_set(&sbi->alloc_valid_block_count, 0); - percpu_counter_set(&sbi->rf_node_block_count, 0); - /* Here, we have one bio having CP pack except cp pack 2 page */ f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO); /* Wait for all dirty meta pages to be submitted for IO */ |