linux.git/fs/f2fs/data.c, branch v5.15

Merge tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2021-09-04T17:48:47+00:00

Pull f2fs updates from Jaegeuk Kim:
 "In this cycle, we've addressed some performance issues such as lock
  contention, misbehaving compress_cache, allowing extent_cache for
  compressed files, and new sysfs to adjust ra_size for fadvise.

  In order to diagnose the performance issues quickly, we also added an
  iostat which shows the IO latencies periodically.

  On the stability side, we've found two memory leakage cases in the
  error path in compression flow. And, we've also fixed various corner
  cases in fiemap, quota, checkpoint=disable, zstd, and so on.

  Enhancements:
   - avoid long checkpoint latency by releasing nat_tree_lock
   - collect and show iostats periodically
   - support extent_cache for compressed files
   - add a sysfs entry to manage ra_size given fadvise(POSIX_FADV_SEQUENTIAL)
   - report f2fs GC status via sysfs
   - add discard_unit=%s in mount option to handle zoned device

  Bug fixes:
   - fix two memory leakages when an error happens in the compressed IO flow
   - fix commpress_cache to get the right LBA
   - fix fiemap to deal with compressed case correctly
   - fix wrong EIO returns due to SBI_NEED_FSCK
   - fix missing writes when enabling checkpoint back
   - fix quota deadlock
   - fix zstd level mount option

  In addition to the above major updates, we've cleaned up several code
  paths such as dio, unnecessary operations, debugfs/f2fs/status, sanity
  check, and typos"

* tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (46 commits)
  f2fs: should put a page beyond EOF when preparing a write
  f2fs: deallocate compressed pages when error happens
  f2fs: enable realtime discard iff device supports discard
  f2fs: guarantee to write dirty data when enabling checkpoint back
  f2fs: fix to unmap pages from userspace process in punch_hole()
  f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()
  f2fs: fix to account missing .skipped_gc_rwsem
  f2fs: adjust unlock order for cleanup
  f2fs: Don't create discard thread when device doesn't support realtime discard
  f2fs: rebuild nat_bits during umount
  f2fs: introduce periodic iostat io latency traces
  f2fs: separate out iostat feature
  f2fs: compress: do sanity check on cluster
  f2fs: fix description about main_blkaddr node
  f2fs: convert S_IRUGO to 0444
  f2fs: fix to keep compatibility of fault injection interface
  f2fs: support fault injection for f2fs_kmem_cache_alloc()
  f2fs: compress: allow write compress released file after truncate to zero
  f2fs: correct comment in segment.h
  f2fs: improve sbi status info in debugfs/f2fs/status
  ...

f2fs: should put a page beyond EOF when preparing a write

2021-08-31T21:39:39+00:00

The prepare_compress_overwrite() gets/locks a page to prepare a read, and calls
f2fs_read_multi_pages() which checks EOF first. If there's any page beyond EOF,
we unlock the page and set cc->rpages[i] = NULL, which we can't put the page
anymore. This makes page leak, so let's fix by putting that page.

Fixes: a949dc5f2c5c ("f2fs: compress: fix race condition of overwrite vs truncate")
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()

2021-08-30T17:12:47+00:00

In below path, it will return ENOENT if filesystem is shutdown:

- f2fs_map_blocks
 - f2fs_get_dnode_of_data
  - f2fs_get_node_page
   - __get_node_page
    - read_node_page
     - is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN)
       return -ENOENT
 - force return value from ENOENT to 0

It should be fine for read case, since it indicates a hole condition,
and caller could use .m_next_pgofs to skip the hole and continue the
lookup.

However it may cause confusing for write case, since leaving a hole
there, and said nothing was wrong doesn't help.

There is at least one case from dax_iomap_actor() will complain that,
so fix this in prior to supporting dax in f2fs.

xfstest generic/388 reports below warning:

ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 485833 at fs/dax.c:1127 dax_iomap_actor+0x339/0x370
Call Trace:
 iomap_apply+0x1c4/0x7b0
 ? dax_iomap_rw+0x1c0/0x1c0
 dax_iomap_rw+0xad/0x1c0
 ? dax_iomap_rw+0x1c0/0x1c0
 f2fs_file_write_iter+0x5ab/0x970 [f2fs]
 do_iter_readv_writev+0x273/0x2e0
 do_iter_write+0xab/0x1f0
 vfs_iter_write+0x21/0x40
 iter_file_splice_write+0x287/0x540
 do_splice+0x37c/0xa60
 __x64_sys_splice+0x15f/0x3a0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xae

ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs:
------------[ cut here ]------------
RIP: 0010:dax_iomap_pte_fault.isra.0+0x72e/0x14a0
Call Trace:
 dax_iomap_fault+0x44/0x70
 f2fs_dax_huge_fault+0x155/0x400 [f2fs]
 f2fs_dax_fault+0x18/0x30 [f2fs]
 __do_fault+0x4e/0x120
 do_fault+0x3cf/0x7a0
 __handle_mm_fault+0xa8c/0xf20
 ? find_held_lock+0x39/0xd0
 handle_mm_fault+0x1b6/0x480
 do_user_addr_fault+0x320/0xcd0
 ? rcu_read_lock_sched_held+0x67/0xc0
 exc_page_fault+0x77/0x3f0
 ? asm_exc_page_fault+0x8/0x30
 asm_exc_page_fault+0x1e/0x30

Fixes: 83a3bfdb5a8a ("f2fs: indicate shutdown f2fs to allow unmount successfully")
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: introduce periodic iostat io latency traces

2021-08-23T17:25:51+00:00

Whenever we notice some sluggish issues on our machines, we are always
curious about how well all types of I/O in the f2fs filesystem are
handled. But, it's hard to get this kind of real data. First of all,
we need to reproduce the issue while turning on the profiling tool like
blktrace, but the issue doesn't happen again easily. Second, with the
intervention of any tools, the overall timing of the issue will be
slightly changed and it sometimes makes us hard to figure it out.

So, I added the feature printing out IO latency statistics tracepoint
events, which are minimal things to understand filesystem's I/O related
behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs
node on, we can get this statistics info in a periodic way and it
would cause the least overhead.

[samples]
 f2fs_ckpt-254:1-507     [003] ....  2842.439683: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4],
wr_sync_data [164/16/3331], wr_sync_node [152/3/648],
wr_sync_meta [160/2/4243], wr_async_data [24/13/15],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

 f2fs_ckpt-254:1-507     [002] ....  2845.450514: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1],
wr_sync_data [120/12/2285], wr_sync_node [88/5/428],
wr_sync_meta [52/6/2990], wr_async_data [4/1/3],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

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

f2fs: separate out iostat feature

2021-08-23T17:25:51+00:00

Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.

Signed-off-by: Daeho Jeong 
Reviewed-by: Chao Yu 
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim

f2fs: compress: do sanity check on cluster

2021-08-17T18:59:06+00:00

This patch adds f2fs_sanity_check_cluster() to support doing
sanity check on cluster of compressed file, it will be triggered
from below two paths:

- __f2fs_cluster_blocks()
- f2fs_map_blocks(F2FS_GET_BLOCK_FIEMAP)

And it can detect below three kind of cluster insanity status.

C: COMPRESS_ADDR
N: NULL_ADDR or NEW_ADDR
V: valid blkaddr
*: any value

1. [*|C|*|*]
2. [C|*|C|*]
3. [C|N|N|V]

Signed-off-by: Chao Yu 
[Nathan Chancellor: fix missing inline warning]
Signed-off-by: Jaegeuk Kim

f2fs: support fault injection for f2fs_kmem_cache_alloc()

2021-08-17T18:59:05+00:00

This patch supports to inject fault into f2fs_kmem_cache_alloc().

Usage:
a) echo 32768 > /sys/fs/f2fs//inject_type or
b) mount -o fault_type=32768  

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

f2fs: compress: avoid duplicate counting of valid blocks when read compressed file

2021-08-12T20:46:05+00:00

Since cluster is basic unit of compression, one cluster is compressed or
not, so we can calculate valid blocks only for first page in cluster,
the other pages just skip.

Signed-off-by: Fengnan Chang 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: extent cache: support unaligned extent

2021-08-05T18:26:11+00:00

Compressed inode may suffer read performance issue due to it can not
use extent cache, so I propose to add this unaligned extent support
to improve it.

Currently, it only works in readonly format f2fs image.

Unaligned extent: in one compressed cluster, physical block number
will be less than logical block number, so we add an extra physical
block length in extent info in order to indicate such extent status.

The idea is if one whole cluster blocks are contiguous physically,
once its mapping info was readed at first time, we will cache an
unaligned (or aligned) extent info entry in extent cache, it expects
that the mapping info will be hitted when rereading cluster.

Merge policy:
- Aligned extents can be merged.
- Aligned extent and unaligned extent can not be merged.

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

f2fs: turn back remapped address in compressed page endio

2021-08-02T18:24:25+00:00

Turned back the remmaped sector address to the address in the partition,
when ending io, for compress cache to work properly.

Fixes: 6ce19aff0b8c ("f2fs: compress: add compress_inode to cache
compressed blocks")
Signed-off-by: Daeho Jeong 
Signed-off-by: Youngjin Gil 
Signed-off-by: Hyeong Jun Kim 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim