<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/f2fs/segment.c, branch v6.11</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>f2fs: use meta inode for GC of atomic file</title>
<updated>2024-07-10T22:48:04+00:00</updated>
<author>
<name>Sunmin Jeong</name>
<email>s_min.jeong@samsung.com</email>
</author>
<published>2024-07-10T11:51:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b40a2b00370931b0c50148681dd7364573e52e6b'/>
<id>b40a2b00370931b0c50148681dd7364573e52e6b</id>
<content type='text'>
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-&gt;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 &lt;sj1557.seo@samsung.com&gt;
Reviewed-by: Yeongjin Gil &lt;youngjin.gil@samsung.com&gt;
Signed-off-by: Sunmin Jeong &lt;s_min.jeong@samsung.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>
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-&gt;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 &lt;sj1557.seo@samsung.com&gt;
Reviewed-by: Yeongjin Gil &lt;youngjin.gil@samsung.com&gt;
Signed-off-by: Sunmin Jeong &lt;s_min.jeong@samsung.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: only fragment segment in the same section</title>
<updated>2024-07-10T22:47:58+00:00</updated>
<author>
<name>Sheng Yong</name>
<email>shengyong@oppo.com</email>
</author>
<published>2024-07-10T01:26:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e3a19972a49f61775e5e11ac43a663f28cdfb8b2'/>
<id>e3a19972a49f61775e5e11ac43a663f28cdfb8b2</id>
<content type='text'>
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 &gt; /sys/fs/f2fs/loop0/max_fragment_chunk
  echo 512 &gt; /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-&gt;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 &lt;chao@kernel.org&gt;
Signed-off-by: Sheng Yong &lt;shengyong@oppo.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>
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 &gt; /sys/fs/f2fs/loop0/max_fragment_chunk
  echo 512 &gt; /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-&gt;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 &lt;chao@kernel.org&gt;
Signed-off-by: Sheng Yong &lt;shengyong@oppo.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: assign CURSEG_ALL_DATA_ATGC if blkaddr is valid</title>
<updated>2024-06-21T22:55:16+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk@kernel.org</email>
</author>
<published>2024-06-18T02:15:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8cb1f4080dd91c6e6b01dbea013a3f42341cb6a1'/>
<id>8cb1f4080dd91c6e6b01dbea013a3f42341cb6a1</id>
<content type='text'>
mkdir /mnt/test/comp
f2fs_io setflags compression /mnt/test/comp
dd if=/dev/zero of=/mnt/test/comp/testfile bs=16k count=1
truncate --size 13 /mnt/test/comp/testfile

In the above scenario, we can get a BUG_ON.
 kernel BUG at fs/f2fs/segment.c:3589!
 Call Trace:
  do_write_page+0x78/0x390 [f2fs]
  f2fs_outplace_write_data+0x62/0xb0 [f2fs]
  f2fs_do_write_data_page+0x275/0x740 [f2fs]
  f2fs_write_single_data_page+0x1dc/0x8f0 [f2fs]
  f2fs_write_multi_pages+0x1e5/0xae0 [f2fs]
  f2fs_write_cache_pages+0xab1/0xc60 [f2fs]
  f2fs_write_data_pages+0x2d8/0x330 [f2fs]
  do_writepages+0xcf/0x270
  __writeback_single_inode+0x44/0x350
  writeback_sb_inodes+0x242/0x530
  __writeback_inodes_wb+0x54/0xf0
  wb_writeback+0x192/0x310
  wb_workfn+0x30d/0x400

The reason is we gave CURSEG_ALL_DATA_ATGC to COMPR_ADDR where the
page was set the gcing flag by set_cluster_dirty().

Cc: stable@vger.kernel.org
Fixes: 4961acdd65c9 ("f2fs: fix to tag gcing flag on page during block migration")
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Tested-by: Will McVicker &lt;willmcvicker@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>
mkdir /mnt/test/comp
f2fs_io setflags compression /mnt/test/comp
dd if=/dev/zero of=/mnt/test/comp/testfile bs=16k count=1
truncate --size 13 /mnt/test/comp/testfile

In the above scenario, we can get a BUG_ON.
 kernel BUG at fs/f2fs/segment.c:3589!
 Call Trace:
  do_write_page+0x78/0x390 [f2fs]
  f2fs_outplace_write_data+0x62/0xb0 [f2fs]
  f2fs_do_write_data_page+0x275/0x740 [f2fs]
  f2fs_write_single_data_page+0x1dc/0x8f0 [f2fs]
  f2fs_write_multi_pages+0x1e5/0xae0 [f2fs]
  f2fs_write_cache_pages+0xab1/0xc60 [f2fs]
  f2fs_write_data_pages+0x2d8/0x330 [f2fs]
  do_writepages+0xcf/0x270
  __writeback_single_inode+0x44/0x350
  writeback_sb_inodes+0x242/0x530
  __writeback_inodes_wb+0x54/0xf0
  wb_writeback+0x192/0x310
  wb_workfn+0x30d/0x400

The reason is we gave CURSEG_ALL_DATA_ATGC to COMPR_ADDR where the
page was set the gcing flag by set_cluster_dirty().

Cc: stable@vger.kernel.org
Fixes: 4961acdd65c9 ("f2fs: fix to tag gcing flag on page during block migration")
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Tested-by: Will McVicker &lt;willmcvicker@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: enable atgc dynamically if conditions are met</title>
<updated>2024-06-18T02:26:58+00:00</updated>
<author>
<name>Zhiguo Niu</name>
<email>zhiguo.niu@unisoc.com</email>
</author>
<published>2024-06-07T09:00:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6efc3a05e6132812edf7eee0eb040eb88af34203'/>
<id>6efc3a05e6132812edf7eee0eb040eb88af34203</id>
<content type='text'>
Now atgc can only be enabled when umounted-&gt;mounted device
even related conditions have reached. If the device has not
be umounted-&gt;mounted for a long time, atgc can not work.

So enable atgc dynamically when atgc_age_threshold is less than
elapsed_time and ATGC mount option is on.

Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.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>
Now atgc can only be enabled when umounted-&gt;mounted device
even related conditions have reached. If the device has not
be umounted-&gt;mounted for a long time, atgc can not work.

So enable atgc dynamically when atgc_age_threshold is less than
elapsed_time and ATGC mount option is on.

Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix to avoid use SSR allocate when do defragment</title>
<updated>2024-06-12T15:46:02+00:00</updated>
<author>
<name>Zhiguo Niu</name>
<email>zhiguo.niu@unisoc.com</email>
</author>
<published>2024-05-29T09:47:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=21327a042dd94bc73181d7300e688699cb1f467e'/>
<id>21327a042dd94bc73181d7300e688699cb1f467e</id>
<content type='text'>
SSR allocate mode will be used when doing file defragment
if ATGC is working at the same time, that is because
set_page_private_gcing may make CURSEG_ALL_DATA_ATGC segment
type got in f2fs_allocate_data_block when defragment page
is writeback, which may cause file fragmentation is worse.

A file with 2 fragmentations is changed as following after defragment:

----------------file info-------------------
sensorsdata :
--------------------------------------------
dev       [254:48]
ino       [0x    3029 : 12329]
mode      [0x    81b0 : 33200]
nlink     [0x       1 : 1]
uid       [0x    27e6 : 10214]
gid       [0x    27e6 : 10214]
size      [0x  242000 : 2367488]
blksize   [0x    1000 : 4096]
blocks    [0x    1210 : 4624]
--------------------------------------------

file_pos   start_blk     end_blk        blks
       0    11361121    11361207          87
  356352    11361215    11361216           2
  364544    11361218    11361218           1
  368640    11361220    11361221           2
  376832    11361224    11361225           2
  385024    11361227    11361238          12
  434176    11361240    11361252          13
  487424    11361254    11361254           1
  491520    11361271    11361279           9
  528384     3681794     3681795           2
  536576     3681797     3681797           1
  540672     3681799     3681799           1
  544768     3681803     3681803           1
  548864     3681805     3681805           1
  552960     3681807     3681807           1
  557056     3681809     3681809           1

Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.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>
SSR allocate mode will be used when doing file defragment
if ATGC is working at the same time, that is because
set_page_private_gcing may make CURSEG_ALL_DATA_ATGC segment
type got in f2fs_allocate_data_block when defragment page
is writeback, which may cause file fragmentation is worse.

A file with 2 fragmentations is changed as following after defragment:

----------------file info-------------------
sensorsdata :
--------------------------------------------
dev       [254:48]
ino       [0x    3029 : 12329]
mode      [0x    81b0 : 33200]
nlink     [0x       1 : 1]
uid       [0x    27e6 : 10214]
gid       [0x    27e6 : 10214]
size      [0x  242000 : 2367488]
blksize   [0x    1000 : 4096]
blocks    [0x    1210 : 4624]
--------------------------------------------

file_pos   start_blk     end_blk        blks
       0    11361121    11361207          87
  356352    11361215    11361216           2
  364544    11361218    11361218           1
  368640    11361220    11361221           2
  376832    11361224    11361225           2
  385024    11361227    11361238          12
  434176    11361240    11361252          13
  487424    11361254    11361254           1
  491520    11361271    11361279           9
  528384     3681794     3681795           2
  536576     3681797     3681797           1
  540672     3681799     3681799           1
  544768     3681803     3681803           1
  548864     3681805     3681805           1
  552960     3681807     3681807           1
  557056     3681809     3681809           1

Signed-off-by: Zhiguo Niu &lt;zhiguo.niu@unisoc.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: alloc new section if curseg is not the first seg in its zone</title>
<updated>2024-06-12T15:46:02+00:00</updated>
<author>
<name>Sheng Yong</name>
<email>shengyong@oppo.com</email>
</author>
<published>2024-05-30T10:01:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=76da333f4b935af65c9465277032a1e24405375c'/>
<id>76da333f4b935af65c9465277032a1e24405375c</id>
<content type='text'>
If curseg is not the first segment in its zone, the zone is not empty.
A new section should be allocated and avoid resetting the old zone.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Sheng Yong &lt;shengyong@oppo.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>
If curseg is not the first segment in its zone, the zone is not empty.
A new section should be allocated and avoid resetting the old zone.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Sheng Yong &lt;shengyong@oppo.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: allow dirty sections with zero valid block for checkpoint disabled</title>
<updated>2024-05-11T00:39:07+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2024-05-10T13:49:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f2526c5cf1d94359467d9472387363d57c6b3e6d'/>
<id>f2526c5cf1d94359467d9472387363d57c6b3e6d</id>
<content type='text'>
Following the semantic for dirty segments in checkpoint disabled mode,
apply the same rule to dirty sections.

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>
Following the semantic for dirty segments in checkpoint disabled mode,
apply the same rule to dirty sections.

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: use f2fs_{err,info}_ratelimited() for cleanup</title>
<updated>2024-05-09T01:02:42+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2024-05-06T10:47:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a78118406d52dde495311c0c4917613868b53169'/>
<id>a78118406d52dde495311c0c4917613868b53169</id>
<content type='text'>
Commit b1c9d3f833ba ("f2fs: support printk_ratelimited() in f2fs_printk()")
missed some cases, cover all remains for cleanup.

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>
Commit b1c9d3f833ba ("f2fs: support printk_ratelimited() in f2fs_printk()")
missed some cases, cover all remains for cleanup.

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 avoid allocating WARM_DATA segment for direct IO</title>
<updated>2024-04-29T17:41:17+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2024-04-26T09:33:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a320b2f08b3b26fff0a71777f018553fc1e6873e'/>
<id>a320b2f08b3b26fff0a71777f018553fc1e6873e</id>
<content type='text'>
If active_log is not 6, we never use WARM_DATA segment, let's
avoid allocating WARM_DATA segment for direct IO.

Signed-off-by: Yunlei He &lt;heyunlei@oppo.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>
If active_log is not 6, we never use WARM_DATA segment, let's
avoid allocating WARM_DATA segment for direct IO.

Signed-off-by: Yunlei He &lt;heyunlei@oppo.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: remove redundant parameter in is_next_segment_free()</title>
<updated>2024-04-29T17:41:17+00:00</updated>
<author>
<name>Yifan Zhao</name>
<email>zhaoyifan@sjtu.edu.cn</email>
</author>
<published>2024-04-25T14:55:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ecd69be71aad3b9299b37b3d8cc3f0fb6016286f'/>
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is_next_segment_free() takes a redundant `type` parameter. Remove it.

Signed-off-by: Yifan Zhao &lt;zhaoyifan@sjtu.edu.cn&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
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is_next_segment_free() takes a redundant `type` parameter. Remove it.

Signed-off-by: Yifan Zhao &lt;zhaoyifan@sjtu.edu.cn&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
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