<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/f2fs/sysfs.c, branch v6.16</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>f2fs: sysfs: export linear_lookup in features directory</title>
<updated>2025-05-06T15:46:54+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2025-04-16T05:48:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=617e0491abe4d8d45c5110ca474c0feb428e6828'/>
<id>617e0491abe4d8d45c5110ca474c0feb428e6828</id>
<content type='text'>
cat /sys/fs/f2fs/features/linear_lookup
supported

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>
cat /sys/fs/f2fs/features/linear_lookup
supported

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: sysfs: add encoding_flags entry</title>
<updated>2025-05-06T15:46:52+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2025-05-06T07:47:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3fea0641b06ff4e53d95d07a96764d8951d4ced6'/>
<id>3fea0641b06ff4e53d95d07a96764d8951d4ced6</id>
<content type='text'>
This patch adds a new sysfs entry /sys/fs/f2fs/&lt;disk&gt;/encoding_flags,
it is a read-only entry to show the value of sb.s_encoding_flags, the
value is hexadecimal.

============================     ==========
Flag_Name                        Flag_Value
============================     ==========
SB_ENC_STRICT_MODE_FL            0x00000001
SB_ENC_NO_COMPAT_FALLBACK_FL     0x00000002
============================     ==========

case#1
mkfs.f2fs -f -O casefold -C utf8:strict /dev/vda
mount /dev/vda /mnt/f2fs
cat /sys/fs/f2fs/vda/encoding_flags
1

case#2
mkfs.f2fs -f -O casefold -C utf8 /dev/vda
fsck.f2fs --nolinear-lookup=1 /dev/vda
mount /dev/vda /mnt/f2fs
cat /sys/fs/f2fs/vda/encoding_flags
2

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>
This patch adds a new sysfs entry /sys/fs/f2fs/&lt;disk&gt;/encoding_flags,
it is a read-only entry to show the value of sb.s_encoding_flags, the
value is hexadecimal.

============================     ==========
Flag_Name                        Flag_Value
============================     ==========
SB_ENC_STRICT_MODE_FL            0x00000001
SB_ENC_NO_COMPAT_FALLBACK_FL     0x00000002
============================     ==========

case#1
mkfs.f2fs -f -O casefold -C utf8:strict /dev/vda
mount /dev/vda /mnt/f2fs
cat /sys/fs/f2fs/vda/encoding_flags
1

case#2
mkfs.f2fs -f -O casefold -C utf8 /dev/vda
fsck.f2fs --nolinear-lookup=1 /dev/vda
mount /dev/vda /mnt/f2fs
cat /sys/fs/f2fs/vda/encoding_flags
2

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: fix to update injection attrs according to fault_option</title>
<updated>2025-04-10T03:59:58+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2025-03-20T02:22:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2be96c2147e25d5845c1b06dc20521ab9e0eeeb0'/>
<id>2be96c2147e25d5845c1b06dc20521ab9e0eeeb0</id>
<content type='text'>
When we update inject type via sysfs, it shows wrong rate value as
below, there is a same problem when we update inject rate, fix it.

Before:
F2FS-fs (vdd): build fault injection attr: rate: 0, type: 0xffff
F2FS-fs (vdd): build fault injection attr: rate: 1, type: 0x0

After:
F2FS-fs (vdd): build fault injection type: 0x1
F2FS-fs (vdd): build fault injection rate: 1

Meanwhile, let's avoid turning on all fault types when we enable fault
injection via fault_injection mount option, it will lead to shutdown
filesystem or fail the mount() easily.

mount -o fault_injection=4 /dev/vdd /mnt/f2fs
F2FS-fs (vdd): build fault injection attr: rate: 4, type: 0x7fffff
F2FS-fs (vdd): inject kmalloc in f2fs_kmalloc of f2fs_fill_super+0xbdf/0x27c0

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>
When we update inject type via sysfs, it shows wrong rate value as
below, there is a same problem when we update inject rate, fix it.

Before:
F2FS-fs (vdd): build fault injection attr: rate: 0, type: 0xffff
F2FS-fs (vdd): build fault injection attr: rate: 1, type: 0x0

After:
F2FS-fs (vdd): build fault injection type: 0x1
F2FS-fs (vdd): build fault injection rate: 1

Meanwhile, let's avoid turning on all fault types when we enable fault
injection via fault_injection mount option, it will lead to shutdown
filesystem or fail the mount() easily.

mount -o fault_injection=4 /dev/vdd /mnt/f2fs
F2FS-fs (vdd): build fault injection attr: rate: 4, type: 0x7fffff
F2FS-fs (vdd): inject kmalloc in f2fs_kmalloc of f2fs_fill_super+0xbdf/0x27c0

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 a proc entry show inject stats</title>
<updated>2025-04-10T03:59:57+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2025-03-20T02:22:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e073e92789839d10a8828c13f9fe47ee517aa8e6'/>
<id>e073e92789839d10a8828c13f9fe47ee517aa8e6</id>
<content type='text'>
This patch adds a proc entry named inject_stats to show total injected
count for each fault type.

cat /proc/fs/f2fs/&lt;dev&gt;/inject_stats
fault_type              injected_count
kmalloc                 0
kvmalloc                0
page alloc              0
page get                0
alloc bio(obsolete)     0
alloc nid               0
orphan                  0
no more block           0
too big dir depth       0
evict_inode fail        0
truncate fail           0
read IO error           0
checkpoint error        0
discard error           0
write IO error          0
slab alloc              0
dquot initialize        0
lock_op                 0
invalid blkaddr         0
inconsistent blkaddr    0
no free segment         0
inconsistent footer     0

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>
This patch adds a proc entry named inject_stats to show total injected
count for each fault type.

cat /proc/fs/f2fs/&lt;dev&gt;/inject_stats
fault_type              injected_count
kmalloc                 0
kvmalloc                0
page alloc              0
page get                0
alloc bio(obsolete)     0
alloc nid               0
orphan                  0
no more block           0
too big dir depth       0
evict_inode fail        0
truncate fail           0
read IO error           0
checkpoint error        0
discard error           0
write IO error          0
slab alloc              0
dquot initialize        0
lock_op                 0
invalid blkaddr         0
inconsistent blkaddr    0
no free segment         0
inconsistent footer     0

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 carve_out sysfs node</title>
<updated>2025-03-13T18:15:59+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2025-03-11T18:29:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d7b549def0eb42a950eebd3bd5343f5c8088c305'/>
<id>d7b549def0eb42a950eebd3bd5343f5c8088c305</id>
<content type='text'>
For several zoned storage devices, vendors will provide extra space
which was used for device level GC than specs and F2FS can use this
space for filesystem level GC. To do that, we can reserve the space
using reserved_blocks. However, it is not enough, since this extra
space should not be shown to users. So, with this new sysfs node,
we can hide the space by substracting reserved_blocks from total
bytes.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.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>
For several zoned storage devices, vendors will provide extra space
which was used for device level GC than specs and F2FS can use this
space for filesystem level GC. To do that, we can reserve the space
using reserved_blocks. However, it is not enough, since this extra
space should not be shown to users. So, with this new sysfs node,
we can hide the space by substracting reserved_blocks from total
bytes.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.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>
<entry>
<title>f2fs: add a sysfs entry to reclaim POSIX_FADV_NOREUSE pages</title>
<updated>2025-02-13T17:58:36+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk@kernel.org</email>
</author>
<published>2025-01-31T22:27:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a907f3a68ee26ba493a08a958809208d17f3347e'/>
<id>a907f3a68ee26ba493a08a958809208d17f3347e</id>
<content type='text'>
1. fadvise(fd1, POSIX_FADV_NOREUSE, {0,3});
2. fadvise(fd2, POSIX_FADV_NOREUSE, {1,2});
3. fadvise(fd3, POSIX_FADV_NOREUSE, {3,1});
4. echo 1024 &gt; /sys/fs/f2fs/tuning/reclaim_caches_kb

This gives a way to reclaim file-backed pages by iterating all f2fs mounts until
reclaiming 1MB page cache ranges, registered by #1, #2, and #3.

5. cat /sys/fs/f2fs/tuning/reclaim_caches_kb
-&gt; gives total number of registered file ranges.

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>
1. fadvise(fd1, POSIX_FADV_NOREUSE, {0,3});
2. fadvise(fd2, POSIX_FADV_NOREUSE, {1,2});
3. fadvise(fd3, POSIX_FADV_NOREUSE, {3,1});
4. echo 1024 &gt; /sys/fs/f2fs/tuning/reclaim_caches_kb

This gives a way to reclaim file-backed pages by iterating all f2fs mounts until
reclaiming 1MB page cache ranges, registered by #1, #2, and #3.

5. cat /sys/fs/f2fs/tuning/reclaim_caches_kb
-&gt; gives total number of registered file ranges.

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 f2fs_base_attr for global sysfs entries</title>
<updated>2025-02-06T18:34:43+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk@kernel.org</email>
</author>
<published>2025-01-30T05:06:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=21925ede449e038ed6f9efdfe0e79f15bddc34bc'/>
<id>21925ede449e038ed6f9efdfe0e79f15bddc34bc</id>
<content type='text'>
In /sys/fs/f2fs/features, there's no f2fs_sb_info, so let's avoid to get
the pointer.

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>
In /sys/fs/f2fs/features, there's no f2fs_sb_info, so let's avoid to get
the pointer.

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: procfs: show mtime in segment_bits</title>
<updated>2025-01-22T21:04:56+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2025-01-20T11:19:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f6370a360d46e4cf10f5dde3c857747994fe1fd5'/>
<id>f6370a360d46e4cf10f5dde3c857747994fe1fd5</id>
<content type='text'>
Show mtime in segment_bits for debug.

cat /proc/fs//f2fs/loop0/segment_bits
format: segment_type|valid_blocks|bitmaps|mtime
segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)
0         3|1  | 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
1         4|3  | 00 d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
2         5|0  | 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
3         0|1  | 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff

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>
Show mtime in segment_bits for debug.

cat /proc/fs//f2fs/loop0/segment_bits
format: segment_type|valid_blocks|bitmaps|mtime
segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)
0         3|1  | 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
1         4|3  | 00 d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
2         5|0  | 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff
3         0|1  | 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00| ffffffffffffffff

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 a sysfs node to limit max read extent count per-inode</title>
<updated>2024-11-23T15:48:13+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2024-11-22T06:50:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=009a8241a8e5a14ea2dd0b8db42dbf283527dd44'/>
<id>009a8241a8e5a14ea2dd0b8db42dbf283527dd44</id>
<content type='text'>
Quoted:
"at this time, there are still 1086911 extent nodes in this zombie
extent tree that need to be cleaned up.

crash_arm64_sprd_v8.0.3++&gt; extent_tree.node_cnt ffffff80896cc500
  node_cnt = {
    counter = 1086911
  },
"

As reported by Xiuhong, there will be a huge number of extent nodes
in extent tree, it may potentially cause:
- slab memory fragments
- extreme long time shrink on extent tree
- low mapping efficiency

Let's add a sysfs node to limit max read extent count for each inode,
by default, value of this threshold is 10240, it can be updated
according to user's requirement.

Reported-by: Xiuhong Wang &lt;xiuhong.wang@unisoc.com&gt;
Closes: https://lore.kernel.org/linux-f2fs-devel/20241112110627.1314632-1-xiuhong.wang@unisoc.com/
Signed-off-by: Xiuhong Wang &lt;xiuhong.wang@unisoc.com&gt;
Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.com&gt;
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>
Quoted:
"at this time, there are still 1086911 extent nodes in this zombie
extent tree that need to be cleaned up.

crash_arm64_sprd_v8.0.3++&gt; extent_tree.node_cnt ffffff80896cc500
  node_cnt = {
    counter = 1086911
  },
"

As reported by Xiuhong, there will be a huge number of extent nodes
in extent tree, it may potentially cause:
- slab memory fragments
- extreme long time shrink on extent tree
- low mapping efficiency

Let's add a sysfs node to limit max read extent count for each inode,
by default, value of this threshold is 10240, it can be updated
according to user's requirement.

Reported-by: Xiuhong Wang &lt;xiuhong.wang@unisoc.com&gt;
Closes: https://lore.kernel.org/linux-f2fs-devel/20241112110627.1314632-1-xiuhong.wang@unisoc.com/
Signed-off-by: Xiuhong Wang &lt;xiuhong.wang@unisoc.com&gt;
Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.com&gt;
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: clean up the unused variable additional_reserved_segments</title>
<updated>2024-11-01T01:24:41+00:00</updated>
<author>
<name>LongPing Wei</name>
<email>weilongping@oppo.com</email>
</author>
<published>2024-10-29T10:49:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1df2bc3c8252261860787a02f61797a914b99163'/>
<id>1df2bc3c8252261860787a02f61797a914b99163</id>
<content type='text'>
additional_reserved_segments was introduced by
commit 300a842937fb ("f2fs: fix to reserve space for IO align feature"),
and its initialization was deleted by
commit 87161a2b0aed ("f2fs: deprecate io_bits").

Signed-off-by: LongPing Wei &lt;weilongping@oppo.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>
additional_reserved_segments was introduced by
commit 300a842937fb ("f2fs: fix to reserve space for IO align feature"),
and its initialization was deleted by
commit 87161a2b0aed ("f2fs: deprecate io_bits").

Signed-off-by: LongPing Wei &lt;weilongping@oppo.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>
