6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chao Yu chao@kernel.org
[ Upstream commit 1acd73edbbfef2c3c5b43cba4006a7797eca7050 ]
It will trigger system panic w/ testcase in [1]:
------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.c:2752! RIP: 0010:new_curseg+0xc81/0x2110 Call Trace: f2fs_allocate_data_block+0x1c91/0x4540 do_write_page+0x163/0xdf0 f2fs_outplace_write_data+0x1aa/0x340 f2fs_do_write_data_page+0x797/0x2280 f2fs_write_single_data_page+0x16cd/0x2190 f2fs_write_cache_pages+0x994/0x1c80 f2fs_write_data_pages+0x9cc/0xea0 do_writepages+0x194/0x7a0 filemap_fdatawrite_wbc+0x12b/0x1a0 __filemap_fdatawrite_range+0xbb/0xf0 file_write_and_wait_range+0xa1/0x110 f2fs_do_sync_file+0x26f/0x1c50 f2fs_sync_file+0x12b/0x1d0 vfs_fsync_range+0xfa/0x230 do_fsync+0x3d/0x80 __x64_sys_fsync+0x37/0x50 x64_sys_call+0x1e88/0x20d0 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e
The root cause is if checkpoint_disabling and lfs_mode are both on, it will trigger OPU for all overwritten data, it may cost more free segment than expected, so f2fs must account those data correctly to calculate cosumed free segments later, and return ENOSPC earlier to avoid run out of free segment during block allocation.
[1] https://lore.kernel.org/fstests/20241015025106.3203676-1-chao@kernel.org/
Fixes: 4354994f097d ("f2fs: checkpoint disabling") Cc: Daniel Rosenberg drosen@google.com Signed-off-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/segment.h | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-)
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 952970166d5da..cd2ec6acc7177 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -559,18 +559,21 @@ static inline int reserved_sections(struct f2fs_sb_info *sbi) }
static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi, - unsigned int node_blocks, unsigned int dent_blocks) + unsigned int node_blocks, unsigned int data_blocks, + unsigned int dent_blocks) {
- unsigned segno, left_blocks; + unsigned int segno, left_blocks, blocks; int i;
- /* check current node sections in the worst case. */ - for (i = CURSEG_HOT_NODE; i <= CURSEG_COLD_NODE; i++) { + /* check current data/node sections in the worst case. */ + for (i = CURSEG_HOT_DATA; i < NR_PERSISTENT_LOG; i++) { segno = CURSEG_I(sbi, i)->segno; left_blocks = CAP_BLKS_PER_SEC(sbi) - get_ckpt_valid_blocks(sbi, segno, true); - if (node_blocks > left_blocks) + + blocks = i <= CURSEG_COLD_DATA ? data_blocks : node_blocks; + if (blocks > left_blocks) return false; }
@@ -584,8 +587,9 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi, }
/* - * calculate needed sections for dirty node/dentry - * and call has_curseg_enough_space + * calculate needed sections for dirty node/dentry and call + * has_curseg_enough_space, please note that, it needs to account + * dirty data as well in lfs mode when checkpoint is disabled. */ static inline void __get_secs_required(struct f2fs_sb_info *sbi, unsigned int *lower_p, unsigned int *upper_p, bool *curseg_p) @@ -594,19 +598,30 @@ static inline void __get_secs_required(struct f2fs_sb_info *sbi, get_pages(sbi, F2FS_DIRTY_DENTS) + get_pages(sbi, F2FS_DIRTY_IMETA); unsigned int total_dent_blocks = get_pages(sbi, F2FS_DIRTY_DENTS); + unsigned int total_data_blocks = 0; unsigned int node_secs = total_node_blocks / CAP_BLKS_PER_SEC(sbi); unsigned int dent_secs = total_dent_blocks / CAP_BLKS_PER_SEC(sbi); + unsigned int data_secs = 0; unsigned int node_blocks = total_node_blocks % CAP_BLKS_PER_SEC(sbi); unsigned int dent_blocks = total_dent_blocks % CAP_BLKS_PER_SEC(sbi); + unsigned int data_blocks = 0; + + if (f2fs_lfs_mode(sbi) && + unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) { + total_data_blocks = get_pages(sbi, F2FS_DIRTY_DATA); + data_secs = total_data_blocks / CAP_BLKS_PER_SEC(sbi); + data_blocks = total_data_blocks % CAP_BLKS_PER_SEC(sbi); + }
if (lower_p) - *lower_p = node_secs + dent_secs; + *lower_p = node_secs + dent_secs + data_secs; if (upper_p) *upper_p = node_secs + dent_secs + - (node_blocks ? 1 : 0) + (dent_blocks ? 1 : 0); + (node_blocks ? 1 : 0) + (dent_blocks ? 1 : 0) + + (data_blocks ? 1 : 0); if (curseg_p) *curseg_p = has_curseg_enough_space(sbi, - node_blocks, dent_blocks); + node_blocks, data_blocks, dent_blocks); }
static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,