linux-stable/fs/f2fs
Jaegeuk Kim 743b620cb0 f2fs: avoid infinite GC loop due to stale atomic files
If committing atomic pages is failed when doing f2fs_do_sync_file(), we can
get commited pages but atomic_file being still set like:

- inmem:    0, atomic IO:    4 (Max.   10), volatile IO:    0 (Max.    0)

If GC selects this block, we can get an infinite loop like this:

f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA
f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096
f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234
f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c
f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA
f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096
f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234
f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c

In that moment, we can observe:

[Before]
Try to move 5084219 blocks (BG: 384508)
  - data blocks : 4962373 (274483)
  - node blocks : 121846 (110025)
Skipped : atomic write 4534686 (10)

[After]
Try to move 5088973 blocks (BG: 384508)
  - data blocks : 4967127 (274483)
  - node blocks : 121846 (110025)
Skipped : atomic write 4539440 (10)

So, refactor atomic_write flow like this:
1. start_atomic_write
 - add inmem_list and set atomic_file

2. write()
 - register it in inmem_pages

3. commit_atomic_write
 - if no error, f2fs_drop_inmem_pages()
 - f2fs_commit_inmme_pages() failed
   : __revoked_inmem_pages() was done
 - f2fs_do_sync_file failed
   : abort_atomic_write later

4. abort_atomic_write
 - f2fs_drop_inmem_pages

5. f2fs_drop_inmem_pages
 - clear atomic_file
 - remove inmem_list

Based on this change, when GC fails to move block in atomic_file,
f2fs_drop_inmem_pages_all() can call f2fs_drop_inmem_pages().

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:20 -07:00
..
acl.c f2fs: Replace spaces with tab 2019-05-08 21:23:11 -07:00
acl.h f2fs: add SPDX license identifiers 2018-09-12 13:07:10 -07:00
checkpoint.c f2fs: add a rw_sem to cover quota flag changes 2019-07-02 15:40:41 -07:00
data.c f2fs: enhance f2fs_is_checkpoint_ready()'s readability 2019-09-06 16:18:26 -07:00
debug.c fs: f2fs: Remove unnecessary checks of SM_I(sbi) in update_general_status() 2019-08-23 07:57:12 -07:00
dir.c f2fs: optimize case-insensitive lookups 2019-09-06 16:18:12 -07:00
extent_cache.c f2fs: introduce f2fs_<level> macros to wrap f2fs_printk() 2019-07-02 15:40:40 -07:00
f2fs.h f2fs: fix wrong error injection path in inc_valid_block_count() 2019-09-06 16:18:26 -07:00
file.c f2fs: avoid infinite GC loop due to stale atomic files 2019-09-16 08:38:20 -07:00
gc.c f2fs: Fix indefinite loop in f2fs_gc() 2019-09-09 13:06:11 +01:00
gc.h f2fs: add SPDX license identifiers 2018-09-12 13:07:10 -07:00
hash.c f2fs: Support case-insensitive file name lookups 2019-08-23 07:57:13 -07:00
inline.c f2fs: fix error path of f2fs_convert_inline_page() 2019-09-06 16:18:27 -07:00
inode.c f2fs: enhance f2fs_is_checkpoint_ready()'s readability 2019-09-06 16:18:26 -07:00
Kconfig f2fs: Fix build error while CONFIG_NLS=m 2019-08-23 07:57:14 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
namei.c f2fs: enhance f2fs_is_checkpoint_ready()'s readability 2019-09-06 16:18:26 -07:00
node.c f2fs: fix flushing node pages when checkpoint is disabled 2019-09-06 16:18:26 -07:00
node.h f2fs: check PageWriteback flag for ordered case 2018-12-26 15:16:56 -08:00
recovery.c f2fs: use generic EFSBADCRC/EFSCORRUPTED 2019-07-02 15:40:41 -07:00
segment.c f2fs: avoid infinite GC loop due to stale atomic files 2019-09-16 08:38:20 -07:00
segment.h f2fs: enhance f2fs_is_checkpoint_ready()'s readability 2019-09-06 16:18:26 -07:00
shrinker.c f2fs: fix sbi->extent_list corruption issue 2018-12-26 15:16:54 -08:00
super.c f2fs: fix wrong available node count calculation 2019-08-23 07:57:14 -07:00
sysfs.c f2fs: include charset encoding information in the superblock 2019-08-23 07:57:13 -07:00
trace.c f2fs: do not use mutex lock in atomic context 2019-03-05 19:58:06 -08:00
trace.h f2fs: add SPDX license identifiers 2018-09-12 13:07:10 -07:00
xattr.c f2fs: enhance f2fs_is_checkpoint_ready()'s readability 2019-09-06 16:18:26 -07:00
xattr.h f2fs: fix to avoid accessing xattr across the boundary 2019-05-09 09:43:29 -07:00