<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/f2fs/sysfs.c, branch v5.17</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'unicode-for-next-5.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode</title>
<updated>2022-02-01T19:13:24+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-02-01T19:13:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=630c12862c21a312c15a494922cdbf9c1beb1733'/>
<id>630c12862c21a312c15a494922cdbf9c1beb1733</id>
<content type='text'>
Pull unicode cleanup from Gabriel Krisman Bertazi:
 "A fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into
  the previous CONFIG_UNICODE. It is -rc material since we don't want to
  expose the former symbol on 5.17.

  This has been living on linux-next for the past week"

* tag 'unicode-for-next-5.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
  unicode: clean up the Kconfig symbol confusion
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull unicode cleanup from Gabriel Krisman Bertazi:
 "A fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into
  the previous CONFIG_UNICODE. It is -rc material since we don't want to
  expose the former symbol on 5.17.

  This has been living on linux-next for the past week"

* tag 'unicode-for-next-5.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
  unicode: clean up the Kconfig symbol confusion
</pre>
</div>
</content>
</entry>
<entry>
<title>unicode: clean up the Kconfig symbol confusion</title>
<updated>2022-01-21T00:57:24+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2022-01-18T06:56:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5298d4bfe80f6ae6ae2777bcd1357b0022d98573'/>
<id>5298d4bfe80f6ae6ae2777bcd1357b0022d98573</id>
<content type='text'>
Turn the CONFIG_UNICODE symbol into a tristate that generates some always
built in code and remove the confusing CONFIG_UNICODE_UTF8_DATA symbol.

Note that a lot of the IS_ENABLED() checks could be turned from cpp
statements into normal ifs, but this change is intended to be fairly
mechanic, so that should be cleaned up later.

Fixes: 2b3d04787012 ("unicode: Add utf8-data module")
Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Gabriel Krisman Bertazi &lt;krisman@collabora.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Turn the CONFIG_UNICODE symbol into a tristate that generates some always
built in code and remove the confusing CONFIG_UNICODE_UTF8_DATA symbol.

Note that a lot of the IS_ENABLED() checks could be turned from cpp
statements into normal ifs, but this change is intended to be fairly
mechanic, so that should be cleaned up later.

Fixes: 2b3d04787012 ("unicode: Add utf8-data module")
Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Gabriel Krisman Bertazi &lt;krisman@collabora.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs</title>
<updated>2022-01-19T09:50:20+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-19T09:50:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1d1df41c5a33359a00e919d54eaebfb789711fdc'/>
<id>1d1df41c5a33359a00e919d54eaebfb789711fdc</id>
<content type='text'>
Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've tried to address some performance issues in
  f2fs_checkpoint and direct IO flows. Also, there was a work to enhance
  the page cache management used for compression. Other than them, we've
  done typical work including sysfs, code clean-ups, tracepoint, sanity
  check, in addition to bug fixes on corner cases.

  Enhancements:
   - use iomap for direct IO
   - try to avoid lock contention to improve f2fs_ckpt speed
   - avoid unnecessary memory allocation in compression flow
   - POSIX_FADV_DONTNEED drops the page cache containing compression
     pages
   - add some sysfs entries (gc_urgent_high_remaining, pending_discard)

  Bug fixes:
   - try not to expose unwritten blocks to user by DIO (this was added
     to avoid merge conflict; another patch is coming to address other
     missing case)
   - relax minor error condition for file pinning feature used in
     Android OTA
   - fix potential deadlock case in compression flow
   - should not truncate any block on pinned file

  In addition, we've done some code clean-ups and tracepoint/sanity
  check improvement"

* tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
  f2fs: do not allow partial truncation on pinned file
  f2fs: remove redunant invalidate compress pages
  f2fs: Simplify bool conversion
  f2fs: don't drop compressed page cache in .{invalidate,release}page
  f2fs: fix to reserve space for IO align feature
  f2fs: fix to check available space of CP area correctly in update_ckpt_flags()
  f2fs: support fault injection to f2fs_trylock_op()
  f2fs: clean up __find_inline_xattr() with __find_xattr()
  f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()
  f2fs: do not bother checkpoint by f2fs_get_node_info
  f2fs: avoid down_write on nat_tree_lock during checkpoint
  f2fs: compress: fix potential deadlock of compress file
  f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file
  f2fs: add gc_urgent_high_remaining sysfs node
  f2fs: fix to do sanity check in is_alive()
  f2fs: fix to avoid panic in is_alive() if metadata is inconsistent
  f2fs: fix to do sanity check on inode type during garbage collection
  f2fs: avoid duplicate call of mark_inode_dirty
  f2fs: show number of pending discard commands
  f2fs: support POSIX_FADV_DONTNEED drop compressed page cache
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've tried to address some performance issues in
  f2fs_checkpoint and direct IO flows. Also, there was a work to enhance
  the page cache management used for compression. Other than them, we've
  done typical work including sysfs, code clean-ups, tracepoint, sanity
  check, in addition to bug fixes on corner cases.

  Enhancements:
   - use iomap for direct IO
   - try to avoid lock contention to improve f2fs_ckpt speed
   - avoid unnecessary memory allocation in compression flow
   - POSIX_FADV_DONTNEED drops the page cache containing compression
     pages
   - add some sysfs entries (gc_urgent_high_remaining, pending_discard)

  Bug fixes:
   - try not to expose unwritten blocks to user by DIO (this was added
     to avoid merge conflict; another patch is coming to address other
     missing case)
   - relax minor error condition for file pinning feature used in
     Android OTA
   - fix potential deadlock case in compression flow
   - should not truncate any block on pinned file

  In addition, we've done some code clean-ups and tracepoint/sanity
  check improvement"

* tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
  f2fs: do not allow partial truncation on pinned file
  f2fs: remove redunant invalidate compress pages
  f2fs: Simplify bool conversion
  f2fs: don't drop compressed page cache in .{invalidate,release}page
  f2fs: fix to reserve space for IO align feature
  f2fs: fix to check available space of CP area correctly in update_ckpt_flags()
  f2fs: support fault injection to f2fs_trylock_op()
  f2fs: clean up __find_inline_xattr() with __find_xattr()
  f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()
  f2fs: do not bother checkpoint by f2fs_get_node_info
  f2fs: avoid down_write on nat_tree_lock during checkpoint
  f2fs: compress: fix potential deadlock of compress file
  f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file
  f2fs: add gc_urgent_high_remaining sysfs node
  f2fs: fix to do sanity check in is_alive()
  f2fs: fix to avoid panic in is_alive() if metadata is inconsistent
  f2fs: fix to do sanity check on inode type during garbage collection
  f2fs: avoid duplicate call of mark_inode_dirty
  f2fs: show number of pending discard commands
  f2fs: support POSIX_FADV_DONTNEED drop compressed page cache
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'unicode-for-next-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode</title>
<updated>2022-01-17T03:40:02+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-17T03:40:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6661224e66f03706daea8e27714436851cf01731'/>
<id>6661224e66f03706daea8e27714436851cf01731</id>
<content type='text'>
Pull unicode updates from Gabriel Krisman Bertazi:
 "This includes patches from Christoph Hellwig to split the large data
  tables of the unicode subsystem into a loadable module, which allow
  users to not have them around if case-insensitive filesystems are not
  to be used. It also includes minor code fixes to unicode and its
  users, from the same author.

  All the patches here have been on linux-next releases for the past
  months"

* tag 'unicode-for-next-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
  unicode: only export internal symbols for the selftests
  unicode: Add utf8-data module
  unicode: cache the normalization tables in struct unicode_map
  unicode: move utf8cursor to utf8-selftest.c
  unicode: simplify utf8len
  unicode: remove the unused utf8{,n}age{min,max} functions
  unicode: pass a UNICODE_AGE() tripple to utf8_load
  unicode: mark the version field in struct unicode_map unsigned
  unicode: remove the charset field from struct unicode_map
  f2fs: simplify f2fs_sb_read_encoding
  ext4: simplify ext4_sb_read_encoding
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull unicode updates from Gabriel Krisman Bertazi:
 "This includes patches from Christoph Hellwig to split the large data
  tables of the unicode subsystem into a loadable module, which allow
  users to not have them around if case-insensitive filesystems are not
  to be used. It also includes minor code fixes to unicode and its
  users, from the same author.

  All the patches here have been on linux-next releases for the past
  months"

* tag 'unicode-for-next-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
  unicode: only export internal symbols for the selftests
  unicode: Add utf8-data module
  unicode: cache the normalization tables in struct unicode_map
  unicode: move utf8cursor to utf8-selftest.c
  unicode: simplify utf8len
  unicode: remove the unused utf8{,n}age{min,max} functions
  unicode: pass a UNICODE_AGE() tripple to utf8_load
  unicode: mark the version field in struct unicode_map unsigned
  unicode: remove the charset field from struct unicode_map
  f2fs: simplify f2fs_sb_read_encoding
  ext4: simplify ext4_sb_read_encoding
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: Simplify bool conversion</title>
<updated>2022-01-04T21:20:57+00:00</updated>
<author>
<name>Yang Li</name>
<email>yang.lee@linux.alibaba.com</email>
</author>
<published>2021-12-15T02:38:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d361b690b6fcd0acdb34a56e9054a6eb6be4b0c3'/>
<id>d361b690b6fcd0acdb34a56e9054a6eb6be4b0c3</id>
<content type='text'>
Fix the following coccicheck warning:
./fs/f2fs/sysfs.c:491:41-46: WARNING: conversion to bool not needed here

Reported-by: Abaci Robot &lt;abaci@linux.alibaba.com&gt;
Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix the following coccicheck warning:
./fs/f2fs/sysfs.c:491:41-46: WARNING: conversion to bool not needed here

Reported-by: Abaci Robot &lt;abaci@linux.alibaba.com&gt;
Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix to reserve space for IO align feature</title>
<updated>2022-01-04T21:20:56+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2021-12-11T13:27:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=300a842937fbcfb5a189cea9ba15374fdb0b5c6b'/>
<id>300a842937fbcfb5a189cea9ba15374fdb0b5c6b</id>
<content type='text'>
https://bugzilla.kernel.org/show_bug.cgi?id=204137

With below script, we will hit panic during new segment allocation:

DISK=bingo.img
MOUNT_DIR=/mnt/f2fs

dd if=/dev/zero of=$DISK bs=1M count=105
mkfs.f2fe -a 1 -o 19 -t 1 -z 1 -f -q $DISK

mount -t f2fs $DISK $MOUNT_DIR -o "noinline_dentry,flush_merge,noextent_cache,mode=lfs,io_bits=7,fsync_mode=strict"

for (( i = 0; i &lt; 4096; i++ )); do
	name=`head /dev/urandom | tr -dc A-Za-z0-9 | head -c 10`
	mkdir $MOUNT_DIR/$name
done

umount $MOUNT_DIR
rm $DISK

--- Core dump ---
Call Trace:
 allocate_segment_by_default+0x9d/0x100 [f2fs]
 f2fs_allocate_data_block+0x3c0/0x5c0 [f2fs]
 do_write_page+0x62/0x110 [f2fs]
 f2fs_outplace_write_data+0x43/0xc0 [f2fs]
 f2fs_do_write_data_page+0x386/0x560 [f2fs]
 __write_data_page+0x706/0x850 [f2fs]
 f2fs_write_cache_pages+0x267/0x6a0 [f2fs]
 f2fs_write_data_pages+0x19c/0x2e0 [f2fs]
 do_writepages+0x1c/0x70
 __filemap_fdatawrite_range+0xaa/0xe0
 filemap_fdatawrite+0x1f/0x30
 f2fs_sync_dirty_inodes+0x74/0x1f0 [f2fs]
 block_operations+0xdc/0x350 [f2fs]
 f2fs_write_checkpoint+0x104/0x1150 [f2fs]
 f2fs_sync_fs+0xa2/0x120 [f2fs]
 f2fs_balance_fs_bg+0x33c/0x390 [f2fs]
 f2fs_write_node_pages+0x4c/0x1f0 [f2fs]
 do_writepages+0x1c/0x70
 __writeback_single_inode+0x45/0x320
 writeback_sb_inodes+0x273/0x5c0
 wb_writeback+0xff/0x2e0
 wb_workfn+0xa1/0x370
 process_one_work+0x138/0x350
 worker_thread+0x4d/0x3d0
 kthread+0x109/0x140
 ret_from_fork+0x25/0x30

The root cause here is, with IO alignment feature enables, in worst
case, we need F2FS_IO_SIZE() free blocks space for single one 4k write
due to IO alignment feature will fill dummy pages to make IO being
aligned.

So we will easily run out of free segments during non-inline directory's
data writeback, even in process of foreground GC.

In order to fix this issue, I just propose to reserve additional free
space for IO alignment feature to handle worst case of free space usage
ratio during FGGC.

Fixes: 0a595ebaaa6b ("f2fs: support IO alignment for DATA and NODE writes")
Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
https://bugzilla.kernel.org/show_bug.cgi?id=204137

With below script, we will hit panic during new segment allocation:

DISK=bingo.img
MOUNT_DIR=/mnt/f2fs

dd if=/dev/zero of=$DISK bs=1M count=105
mkfs.f2fe -a 1 -o 19 -t 1 -z 1 -f -q $DISK

mount -t f2fs $DISK $MOUNT_DIR -o "noinline_dentry,flush_merge,noextent_cache,mode=lfs,io_bits=7,fsync_mode=strict"

for (( i = 0; i &lt; 4096; i++ )); do
	name=`head /dev/urandom | tr -dc A-Za-z0-9 | head -c 10`
	mkdir $MOUNT_DIR/$name
done

umount $MOUNT_DIR
rm $DISK

--- Core dump ---
Call Trace:
 allocate_segment_by_default+0x9d/0x100 [f2fs]
 f2fs_allocate_data_block+0x3c0/0x5c0 [f2fs]
 do_write_page+0x62/0x110 [f2fs]
 f2fs_outplace_write_data+0x43/0xc0 [f2fs]
 f2fs_do_write_data_page+0x386/0x560 [f2fs]
 __write_data_page+0x706/0x850 [f2fs]
 f2fs_write_cache_pages+0x267/0x6a0 [f2fs]
 f2fs_write_data_pages+0x19c/0x2e0 [f2fs]
 do_writepages+0x1c/0x70
 __filemap_fdatawrite_range+0xaa/0xe0
 filemap_fdatawrite+0x1f/0x30
 f2fs_sync_dirty_inodes+0x74/0x1f0 [f2fs]
 block_operations+0xdc/0x350 [f2fs]
 f2fs_write_checkpoint+0x104/0x1150 [f2fs]
 f2fs_sync_fs+0xa2/0x120 [f2fs]
 f2fs_balance_fs_bg+0x33c/0x390 [f2fs]
 f2fs_write_node_pages+0x4c/0x1f0 [f2fs]
 do_writepages+0x1c/0x70
 __writeback_single_inode+0x45/0x320
 writeback_sb_inodes+0x273/0x5c0
 wb_writeback+0xff/0x2e0
 wb_workfn+0xa1/0x370
 process_one_work+0x138/0x350
 worker_thread+0x4d/0x3d0
 kthread+0x109/0x140
 ret_from_fork+0x25/0x30

The root cause here is, with IO alignment feature enables, in worst
case, we need F2FS_IO_SIZE() free blocks space for single one 4k write
due to IO alignment feature will fill dummy pages to make IO being
aligned.

So we will easily run out of free segments during non-inline directory's
data writeback, even in process of foreground GC.

In order to fix this issue, I just propose to reserve additional free
space for IO alignment feature to handle worst case of free space usage
ratio during FGGC.

Fixes: 0a595ebaaa6b ("f2fs: support IO alignment for DATA and NODE writes")
Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: add gc_urgent_high_remaining sysfs node</title>
<updated>2021-12-10T23:48:33+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2021-12-09T00:41:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=325163e9892b627fc9fb1af51e51f0f95dded517'/>
<id>325163e9892b627fc9fb1af51e51f0f95dded517</id>
<content type='text'>
Added a new sysfs node called gc_urgent_high_remaining. The user can
set the trial count limit for GC urgent high mode with this value. If
GC thread gets to the limit, the mode will turn back to GC normal mode.
By default, the value is zero, which means there is no limit like before.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Added a new sysfs node called gc_urgent_high_remaining. The user can
set the trial count limit for GC urgent high mode with this value. If
GC thread gets to the limit, the mode will turn back to GC normal mode.
By default, the value is zero, which means there is no limit like before.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: show number of pending discard commands</title>
<updated>2021-12-10T23:48:32+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk@kernel.org</email>
</author>
<published>2021-11-29T18:36:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ae2e2804caa120af188b0d7b08936c7ac5c7d8fe'/>
<id>ae2e2804caa120af188b0d7b08936c7ac5c7d8fe</id>
<content type='text'>
This information can be used to check how much time we need to give to issue
all the discard commands.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This information can be used to check how much time we need to give to issue
all the discard commands.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: introduce fragment allocation mode mount option</title>
<updated>2021-10-26T21:04:30+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2021-09-29T18:12:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6691d940b0e09dd1564130e7a354d6deaf05d009'/>
<id>6691d940b0e09dd1564130e7a354d6deaf05d009</id>
<content type='text'>
Added two options into "mode=" mount option to make it possible for
developers to simulate filesystem fragmentation/after-GC situation
itself. The developers use these modes to understand filesystem
fragmentation/after-GC condition well, and eventually get some
insights to handle them better.

"fragment:segment": f2fs allocates a new segment in ramdom position.
		With this, we can simulate the after-GC condition.
"fragment:block" : We can scatter block allocation with
		"max_fragment_chunk" and "max_fragment_hole" sysfs
		nodes. f2fs will allocate 1..&lt;max_fragment_chunk&gt;
		blocks in a chunk and make a hole in the length of
		1..&lt;max_fragment_hole&gt; by turns	in a newly allocated
		free segment. Plus, this mode implicitly enables
		"fragment:segment" option for more randomness.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Added two options into "mode=" mount option to make it possible for
developers to simulate filesystem fragmentation/after-GC situation
itself. The developers use these modes to understand filesystem
fragmentation/after-GC condition well, and eventually get some
insights to handle them better.

"fragment:segment": f2fs allocates a new segment in ramdom position.
		With this, we can simulate the after-GC condition.
"fragment:block" : We can scatter block allocation with
		"max_fragment_chunk" and "max_fragment_hole" sysfs
		nodes. f2fs will allocate 1..&lt;max_fragment_chunk&gt;
		blocks in a chunk and make a hole in the length of
		1..&lt;max_fragment_hole&gt; by turns	in a newly allocated
		free segment. Plus, this mode implicitly enables
		"fragment:segment" option for more randomness.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: replace snprintf in show functions with sysfs_emit</title>
<updated>2021-10-26T21:04:30+00:00</updated>
<author>
<name>Qing Wang</name>
<email>wangqing@vivo.com</email>
</author>
<published>2021-10-13T03:29:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=84eab2a899f28137e51a36861ed2df9579f54ebe'/>
<id>84eab2a899f28137e51a36861ed2df9579f54ebe</id>
<content type='text'>
coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the following coccicheck warning:
fs/f2fs/sysfs.c:198:12-20: WARNING: use scnprintf or sprintf.
fs/f2fs/sysfs.c:247:8-16: WARNING: use scnprintf or sprintf.

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Signed-off-by: Qing Wang &lt;wangqing@vivo.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the following coccicheck warning:
fs/f2fs/sysfs.c:198:12-20: WARNING: use scnprintf or sprintf.
fs/f2fs/sysfs.c:247:8-16: WARNING: use scnprintf or sprintf.

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Signed-off-by: Qing Wang &lt;wangqing@vivo.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
