linux.git/fs/f2fs/segment.c, branch v6.12

f2fs: remove unused parameters

2024-09-12T14:42:03+00:00

Remove unused parameter segno from f2fs_usable_segs_in_sec.

Signed-off-by: liuderong 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix to don't panic system for no free segment fault injection

2024-09-11T03:38:14+00:00

f2fs: fix to don't panic system for no free segment fault injection

syzbot reports a f2fs bug as below:

F2FS-fs (loop0): inject no free segment in get_new_segment of __allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3167
F2FS-fs (loop0): Stopped filesystem due to reason: 7
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2748!
CPU: 0 UID: 0 PID: 5109 Comm: syz-executor304 Not tainted 6.11.0-rc6-syzkaller-00363-g89f5e14d05b4 #0
RIP: 0010:get_new_segment fs/f2fs/segment.c:2748 [inline]
RIP: 0010:new_curseg+0x1f61/0x1f70 fs/f2fs/segment.c:2836
Call Trace:
 __allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3167
 f2fs_allocate_new_section fs/f2fs/segment.c:3181 [inline]
 f2fs_allocate_pinning_section+0xfa/0x4e0 fs/f2fs/segment.c:3195
 f2fs_expand_inode_data+0x5d6/0xbb0 fs/f2fs/file.c:1799
 f2fs_fallocate+0x448/0x960 fs/f2fs/file.c:1903
 vfs_fallocate+0x553/0x6c0 fs/open.c:334
 do_vfs_ioctl+0x2592/0x2e50 fs/ioctl.c:886
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0010:get_new_segment fs/f2fs/segment.c:2748 [inline]
RIP: 0010:new_curseg+0x1f61/0x1f70 fs/f2fs/segment.c:2836

The root cause is when we inject no free segment fault into f2fs,
we should not panic system, fix it.

Fixes: 8b10d3653735 ("f2fs: introduce FAULT_NO_SEGMENT")
Reported-by: syzbot+341e5f32ebafbb46b81c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/000000000000f0ee5b0621ab694b@google.com
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: add valid block ratio not to do excessive GC for one time GC

2024-09-11T03:33:08+00:00

We need to introduce a valid block ratio threshold not to trigger
excessive GC for zoned deivces. The initial value of it is 95%. So, F2FS
will stop the thread from intiating GC for sections having valid blocks
exceeding the ratio.

Signed-off-by: Daeho Jeong 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: prevent atomic file from being dirtied before commit

2024-09-11T03:30:27+00:00

Keep atomic file clean while updating and make it dirtied during commit
in order to avoid unnecessary and excessive inode updates in the previous
fix.

Fixes: 4bf78322346f ("f2fs: mark inode dirty for FI_ATOMIC_COMMITTED flag")
Signed-off-by: Daeho Jeong 
Signed-off-by: Jaegeuk Kim

f2fs: get rid of page->index

2024-09-06T23:04:48+00:00

Convert to use folio, so that we can get rid of 'page->index' to
prepare for removal of 'index' field in structure page [1].

[1] https://lore.kernel.org/all/Zp8fgUSIBGQ1TN0D@casper.infradead.org/

Cc: Matthew Wilcox 
Signed-off-by: Chao Yu 
Reviewed-by: Li Zetao 
Signed-off-by: Jaegeuk Kim

f2fs: convert f2fs_do_write_meta_page() to use folio

2024-09-06T23:04:47+00:00

Convert to use folio, so that we can get rid of 'page->index' to
prepare for removal of 'index' field in structure page [1].

[1] https://lore.kernel.org/all/Zp8fgUSIBGQ1TN0D@casper.infradead.org/

Cc: Matthew Wilcox 
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: check discard support for conventional zones

2024-08-21T00:57:33+00:00

As the helper function f2fs_bdev_support_discard() shows, f2fs checks if
the target block devices support discard by calling
bdev_max_discard_sectors() and bdev_is_zoned(). This check works well
for most cases, but it does not work for conventional zones on zoned
block devices. F2fs assumes that zoned block devices support discard,
and calls __submit_discard_cmd(). When __submit_discard_cmd() is called
for sequential write required zones, it works fine since
__submit_discard_cmd() issues zone reset commands instead of discard
commands. However, when __submit_discard_cmd() is called for
conventional zones, __blkdev_issue_discard() is called even when the
devices do not support discard.

The inappropriate __blkdev_issue_discard() call was not a problem before
the commit 30f1e7241422 ("block: move discard checks into the ioctl
handler") because __blkdev_issue_discard() checked if the target devices
support discard or not. If not, it returned EOPNOTSUPP. After the
commit, __blkdev_issue_discard() no longer checks it. It always returns
zero and sets NULL to the given bio pointer. This NULL pointer triggers
f2fs_bug_on() in __submit_discard_cmd(). The BUG is recreated with the
commands below at the umount step, where /dev/nullb0 is a zoned null_blk
with 5GB total size, 128MB zone size and 10 conventional zones.

$ mkfs.f2fs -f -m /dev/nullb0
$ mount /dev/nullb0 /mnt
$ for ((i=0;i<5;i++)); do dd if=/dev/zero of=/mnt/test bs=65536 count=1600 conv=fsync; done
$ umount /mnt

To fix the BUG, avoid the inappropriate __blkdev_issue_discard() call.
When discard is requested for conventional zones, check if the device
supports discard or not. If not, return EOPNOTSUPP.

Fixes: 30f1e7241422 ("block: move discard checks into the ioctl handler")
Cc: stable@vger.kernel.org
Signed-off-by: Shin'ichiro Kawasaki 
Reviewed-by: Damien Le Moal 
Reviewed-by: Chao Yu 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jaegeuk Kim

f2fs: add write priority option based on zone UFS

2024-08-05T20:18:35+00:00

Currently, we are using a mix of traditional UFS and zone UFS to support
some functionalities that cannot be achieved on zone UFS alone. However,
there are some issues with this approach. There exists a significant
performance difference between traditional UFS and zone UFS. Under normal
usage, we prioritize writes to zone UFS. However, in critical conditions
(such as when the entire UFS is almost full), we cannot determine whether
data will be written to traditional UFS or zone UFS. This can lead to
significant performance fluctuations, which is not conducive to
development and testing. To address this, we have added an option
zlu_io_enable under sys with the following three modes:
1) zlu_io_enable == 0:Normal mode, prioritize writing to zone UFS;
2) zlu_io_enable == 1:Zone UFS only mode, only allow writing to zone UFS;
3) zlu_io_enable == 2:Traditional UFS priority mode, prioritize writing to
traditional UFS.

Signed-off-by: Liao Yuanhong 
Signed-off-by: Wu Bo 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: use meta inode for GC of atomic file

2024-07-10T22:48:04+00:00

The page cache of the atomic file keeps new data pages which will be
stored in the COW file. It can also keep old data pages when GCing the
atomic file. In this case, new data can be overwritten by old data if a
GC thread sets the old data page as dirty after new data page was
evicted.

Also, since all writes to the atomic file are redirected to COW inodes,
GC for the atomic file is not working well as below.

f2fs_gc(gc_type=FG_GC)
  - select A as a victim segment
  do_garbage_collect
    - iget atomic file's inode for block B
    move_data_page
      f2fs_do_write_data_page
        - use dn of cow inode
        - set fio->old_blkaddr from cow inode
    - seg_freed is 0 since block B is still valid
  - goto gc_more and A is selected as victim again

To solve the problem, let's separate GC writes and updates in the atomic
file by using the meta inode for GC writes.

Fixes: 3db1de0e582c ("f2fs: change the current atomic write way")
Cc: stable@vger.kernel.org #v5.19+
Reviewed-by: Sungjong Seo 
Reviewed-by: Yeongjin Gil 
Signed-off-by: Sunmin Jeong 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: only fragment segment in the same section

2024-07-10T22:47:58+00:00

When new_curseg() is allocating a new segment, if mode=fragment:xxx is
switched on in large section scenario, __get_next_segno() will select
the next segno randomly in the range of [0, maxsegno] in order to
fragment segments.

If the candidate segno is free, get_new_segment() will use it directly
as the new segment.

However, if the section of the candidate is not empty, and some other
segments have already been used, and have a different type (e.g NODE)
with the candidate (e.g DATA), GC will complain inconsistent segment
type later.

This could be reproduced by the following steps:

  dd if=/dev/zero of=test.img bs=1M count=10240
  mkfs.f2fs -s 128 test.img
  mount -t f2fs test.img /mnt -o mode=fragment:block
  echo 1 > /sys/fs/f2fs/loop0/max_fragment_chunk
  echo 512 > /sys/fs/f2fs/loop0/max_fragment_hole
  dd if=/dev/zero of=/mnt/testfile bs=4K count=100
  umount /mnt

  F2FS-fs (loop0): Inconsistent segment (4377) type [0, 1] in SSA and SIT

In order to allow simulating segment fragmentation in large section
scenario, this patch reduces the candidate range:
 * if curseg is the last segment in the section, return curseg->segno
   to make get_new_segment() itself find the next free segment.
 * if curseg is in the middle of the section, select candicate randomly
   in the range of [curseg + 1, last_seg_in_the_same_section] to keep
   type consistent.

Reviewed-by: Chao Yu 
Signed-off-by: Sheng Yong 
Signed-off-by: Jaegeuk Kim