<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/f2fs/file.c, branch v3.9.8</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>more file_inode() open-coded instances</title>
<updated>2013-02-27T21:59:05+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2013-02-27T21:59:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6131ffaa1f091415b7a24abb01f033d9c0a727f4'/>
<id>6131ffaa1f091415b7a24abb01f033d9c0a727f4</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: add compat_ioctl to provide backward compatability</title>
<updated>2013-02-11T22:15:02+00:00</updated>
<author>
<name>Namjae Jeon</name>
<email>namjae.jeon@samsung.com</email>
</author>
<published>2013-02-04T14:41:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=e9750824114ff939d9da299e73651add6aa65456'/>
<id>e9750824114ff939d9da299e73651add6aa65456</id>
<content type='text'>
adding compat_ioctl to provide support for backward comptability - 32bit binary
execution on 64bit kernel.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Amit Sahrawat &lt;a.sahrawat@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
adding compat_ioctl to provide support for backward comptability - 32bit binary
execution on 64bit kernel.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Amit Sahrawat &lt;a.sahrawat@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: stop repeated checking if cp is needed</title>
<updated>2013-02-11T22:15:01+00:00</updated>
<author>
<name>Changman Lee</name>
<email>cm224.lee@samsung.com</email>
</author>
<published>2013-01-31T08:16:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=facb0205401a6ce4be410e1f4b9357bbc6caa36a'/>
<id>facb0205401a6ce4be410e1f4b9357bbc6caa36a</id>
<content type='text'>
If it is decided that f2fs should do checkpoint, skip next comparison.

Signed-off-by: Changman Lee &lt;cm224.lee@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If it is decided that f2fs should do checkpoint, skip next comparison.

Signed-off-by: Changman Lee &lt;cm224.lee@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: avoid balanc_fs during evict_inode</title>
<updated>2013-02-11T22:15:01+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2013-01-31T06:36:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=d4686d56ec912d55fd8a9d6d509de50de24e90ab'/>
<id>d4686d56ec912d55fd8a9d6d509de50de24e90ab</id>
<content type='text'>
1. Background

Previously, if f2fs tries to move data blocks of an *evicting* inode during the
cleaning process, it stops the process incompletely and then restarts the whole
process, since it needs a locked inode to grab victim data pages in its address
space. In order to get a locked inode, iget_locked() by f2fs_iget() is normally
used, but, it waits if the inode is on freeing.

So, here is a deadlock scenario.
1. f2fs_evict_inode()       &lt;- inode "A"
  2. f2fs_balance_fs()
    3. f2fs_gc()
      4. gc_data_segment()
        5. f2fs_iget()      &lt;- inode "A" too!

If step #1 and #5 treat a same inode "A", step #5 would fall into deadlock since
the inode "A" is on freeing. In order to resolve this, f2fs_iget_nowait() which
skips __wait_on_freeing_inode() was introduced in step #5, and stops f2fs_gc()
to complete f2fs_evict_inode().

1. f2fs_evict_inode()           &lt;- inode "A"
  2. f2fs_balance_fs()
    3. f2fs_gc()
      4. gc_data_segment()
        5. f2fs_iget_nowait()   &lt;- inode "A", then stop f2fs_gc() w/ -ENOENT

2. Problem and Solution

In the above scenario, however, f2fs cannot finish f2fs_evict_inode() only if:
 o there are not enough free sections, and
 o f2fs_gc() tries to move data blocks of the *evicting* inode repeatedly.

So, the final solution is to use f2fs_iget() and remove f2fs_balance_fs() in
f2fs_evict_inode().
The f2fs_evict_inode() actually truncates all the data and node blocks, which
means that it doesn't produce any dirty node pages accordingly.
So, we don't need to do f2fs_balance_fs() in practical.

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
1. Background

Previously, if f2fs tries to move data blocks of an *evicting* inode during the
cleaning process, it stops the process incompletely and then restarts the whole
process, since it needs a locked inode to grab victim data pages in its address
space. In order to get a locked inode, iget_locked() by f2fs_iget() is normally
used, but, it waits if the inode is on freeing.

So, here is a deadlock scenario.
1. f2fs_evict_inode()       &lt;- inode "A"
  2. f2fs_balance_fs()
    3. f2fs_gc()
      4. gc_data_segment()
        5. f2fs_iget()      &lt;- inode "A" too!

If step #1 and #5 treat a same inode "A", step #5 would fall into deadlock since
the inode "A" is on freeing. In order to resolve this, f2fs_iget_nowait() which
skips __wait_on_freeing_inode() was introduced in step #5, and stops f2fs_gc()
to complete f2fs_evict_inode().

1. f2fs_evict_inode()           &lt;- inode "A"
  2. f2fs_balance_fs()
    3. f2fs_gc()
      4. gc_data_segment()
        5. f2fs_iget_nowait()   &lt;- inode "A", then stop f2fs_gc() w/ -ENOENT

2. Problem and Solution

In the above scenario, however, f2fs cannot finish f2fs_evict_inode() only if:
 o there are not enough free sections, and
 o f2fs_gc() tries to move data blocks of the *evicting* inode repeatedly.

So, the final solution is to use f2fs_iget() and remove f2fs_balance_fs() in
f2fs_evict_inode().
The f2fs_evict_inode() actually truncates all the data and node blocks, which
means that it doesn't produce any dirty node pages accordingly.
So, we don't need to do f2fs_balance_fs() in practical.

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: cover global locks for reserve_new_block</title>
<updated>2013-02-11T22:15:00+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2013-01-25T09:33:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=bd43df021ac37247f2db58ff376fb4032170f754'/>
<id>bd43df021ac37247f2db58ff376fb4032170f754</id>
<content type='text'>
The fill_zero() from fallocate() calls get_new_data_page() in which calls
reserve_new_block().
The reserve_new_block() should be covered by *DATA_NEW*, one of global locks.
And also, before getting the lock, we should check free sections by calling
f2fs_balance_fs().

If we break this rule, f2fs is able to face with out-of-control free space
management and fall into infinite loop like the following scenario as well.

[f2fs_sync_fs()]             [fallocate()]
 - write_checkpoint()        - fill_zero()
  - block_operations()        - get_new_data_page()
   : grab NODE_NEW             - get_dnode_of_data()
                                : get locked dirty node page
    - sync_node_pages()
                                : try to grab NODE_NEW for data allocation
     : trylock and skip the dirty node page
   : call sync_node_pages() repeatedly in order to flush all the dirty node
     pages!

In order to avoid this, we should grab another global lock such as DATA_NEW
before calling get_new_data_page() in fill_zero().

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The fill_zero() from fallocate() calls get_new_data_page() in which calls
reserve_new_block().
The reserve_new_block() should be covered by *DATA_NEW*, one of global locks.
And also, before getting the lock, we should check free sections by calling
f2fs_balance_fs().

If we break this rule, f2fs is able to face with out-of-control free space
management and fall into infinite loop like the following scenario as well.

[f2fs_sync_fs()]             [fallocate()]
 - write_checkpoint()        - fill_zero()
  - block_operations()        - get_new_data_page()
   : grab NODE_NEW             - get_dnode_of_data()
                                : get locked dirty node page
    - sync_node_pages()
                                : try to grab NODE_NEW for data allocation
     : trylock and skip the dirty node page
   : call sync_node_pages() repeatedly in order to flush all the dirty node
     pages!

In order to avoid this, we should grab another global lock such as DATA_NEW
before calling get_new_data_page() in fill_zero().

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: add remap_pages as generic_file_remap_pages</title>
<updated>2013-01-22T01:48:58+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2013-01-17T09:37:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=692bb55d1ab5b278181ff2e65f09eb0be6d50669'/>
<id>692bb55d1ab5b278181ff2e65f09eb0be6d50669</id>
<content type='text'>
This was added for all the file systems before.

See the following commit.

commit id: 0b173bc4daa8f8ec03a85abf5e47b23502ff80af

[PATCH] mm: kill vma flag VM_CAN_NONLINEAR

This patch moves actual ptes filling for non-linear file mappings
into special vma operation: -&gt;remap_pages().

File system must implement this method to get non-linear mappings support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support."

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This was added for all the file systems before.

See the following commit.

commit id: 0b173bc4daa8f8ec03a85abf5e47b23502ff80af

[PATCH] mm: kill vma flag VM_CAN_NONLINEAR

This patch moves actual ptes filling for non-linear file mappings
into special vma operation: -&gt;remap_pages().

File system must implement this method to get non-linear mappings support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support."

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: move f2fs_balance_fs to punch_hole</title>
<updated>2013-01-11T06:09:23+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2013-01-11T05:09:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9eaeba701386037cdd2ccd8bf8650feb2e2cec31'/>
<id>9eaeba701386037cdd2ccd8bf8650feb2e2cec31</id>
<content type='text'>
The f2fs_fallocate() has two operations: punch_hole and expand_size.

Only in the case of punch_hole, dirty node pages can be produced, so let's
trigger f2fs_balance_fs() in this case only.
Furthermore, let's trigger it at every data truncation routine.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The f2fs_fallocate() has two operations: punch_hole and expand_size.

Only in the case of punch_hole, dirty node pages can be produced, so let's
trigger f2fs_balance_fs() in this case only.
Furthermore, let's trigger it at every data truncation routine.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: add f2fs_balance_fs in several interfaces</title>
<updated>2013-01-11T06:09:17+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2013-01-11T04:10:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7d82db83165dbac8c3f6d47b73c84f38e3996e30'/>
<id>7d82db83165dbac8c3f6d47b73c84f38e3996e30</id>
<content type='text'>
The f2fs_balance_fs() is to check the number of free sections and decide whether
it needs to conduct cleaning or not. If there are not enough free sections, the
cleaning job should be started.

In order to control an amount of free sections even under high utilization, f2fs
should call f2fs_balance_fs at all the VFS interfaces that are able to produce
dirty pages.
This patch adds the function calls in the missing interfaces as follows.

1. f2fs_setxattr()
The f2fs_setxattr() produces dirty node pages so that we should call
f2fs_balance_fs() either likewise doing in other VFS interfaces such as
f2fs_lookup(), f2fs_mkdir(), and so on.

2. f2fs_sync_file()
We should guarantee serving free sections for syncing metadata during fsync.
Previously, there is no space check before triggering checkpoint and
sync_node_pages.
Therefore, if a bunch of fsync calls are triggered under 100% of FS utilization,
f2fs is able to be faced with no free sections, resulting in BUG_ON().

3. f2fs_sync_fs()
Before calling write_checkpoint(), we should guarantee that there are minimum
free sections.

4. f2fs_write_inode()
f2fs_write_inode() is also able to produce dirty node pages.

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The f2fs_balance_fs() is to check the number of free sections and decide whether
it needs to conduct cleaning or not. If there are not enough free sections, the
cleaning job should be started.

In order to control an amount of free sections even under high utilization, f2fs
should call f2fs_balance_fs at all the VFS interfaces that are able to produce
dirty pages.
This patch adds the function calls in the missing interfaces as follows.

1. f2fs_setxattr()
The f2fs_setxattr() produces dirty node pages so that we should call
f2fs_balance_fs() either likewise doing in other VFS interfaces such as
f2fs_lookup(), f2fs_mkdir(), and so on.

2. f2fs_sync_file()
We should guarantee serving free sections for syncing metadata during fsync.
Previously, there is no space check before triggering checkpoint and
sync_node_pages.
Therefore, if a bunch of fsync calls are triggered under 100% of FS utilization,
f2fs is able to be faced with no free sections, resulting in BUG_ON().

3. f2fs_sync_fs()
Before calling write_checkpoint(), we should guarantee that there are minimum
free sections.

4. f2fs_write_inode()
f2fs_write_inode() is also able to produce dirty node pages.

Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix time update in case of f2fs fallocate</title>
<updated>2013-01-04T00:42:59+00:00</updated>
<author>
<name>Namjae Jeon</name>
<email>namjae.jeon@samsung.com</email>
</author>
<published>2012-12-30T05:52:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=3af60a49fd2edfe9c5a06bc84d4832450895be96'/>
<id>3af60a49fd2edfe9c5a06bc84d4832450895be96</id>
<content type='text'>
After doing a punch hole or expanding inode doing fallocation.
The change and modification time are not update for the file.
So, update time after no issue is observed in fallocate.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Amit Sahrawat &lt;a.sahrawat@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After doing a punch hole or expanding inode doing fallocation.
The change and modification time are not update for the file.
So, update time after no issue is observed in fallocate.

Signed-off-by: Namjae Jeon &lt;namjae.jeon@samsung.com&gt;
Signed-off-by: Amit Sahrawat &lt;a.sahrawat@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix handling errors got by f2fs_write_inode</title>
<updated>2012-12-26T01:39:52+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk.kim@samsung.com</email>
</author>
<published>2012-12-19T06:28:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=398b1ac5a57219823f942a8d3665b27ab99354de'/>
<id>398b1ac5a57219823f942a8d3665b27ab99354de</id>
<content type='text'>
Ruslan reported that f2fs hangs with an infinite loop in f2fs_sync_file():

	while (sync_node_pages(sbi, inode-&gt;i_ino, &amp;wbc) == 0)
		f2fs_write_inode(inode, NULL);

The reason was revealed that the cold flag is not set even thought this inode is
a normal file. Therefore, sync_node_pages() skips to write node blocks since it
only writes cold node blocks.

The cold flag is stored to the node_footer in node block, and whenever a new
node page is allocated, it is set according to its file type, file or directory.

But, after sudden-power-off, when recovering the inode page, f2fs doesn't recover
its cold flag.

So, let's assign the cold flag in more right places.

One more thing:
If f2fs_write_inode() returns an error due to whatever situations, there would
be no dirty node pages so that sync_node_pages() returns zero.
(i.e., zero means nothing was written.)

Reported-by: Ruslan N. Marchenko &lt;me@ruff.mobi&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Ruslan reported that f2fs hangs with an infinite loop in f2fs_sync_file():

	while (sync_node_pages(sbi, inode-&gt;i_ino, &amp;wbc) == 0)
		f2fs_write_inode(inode, NULL);

The reason was revealed that the cold flag is not set even thought this inode is
a normal file. Therefore, sync_node_pages() skips to write node blocks since it
only writes cold node blocks.

The cold flag is stored to the node_footer in node block, and whenever a new
node page is allocated, it is set according to its file type, file or directory.

But, after sudden-power-off, when recovering the inode page, f2fs doesn't recover
its cold flag.

So, let's assign the cold flag in more right places.

One more thing:
If f2fs_write_inode() returns an error due to whatever situations, there would
be no dirty node pages so that sync_node_pages() returns zero.
(i.e., zero means nothing was written.)

Reported-by: Ruslan N. Marchenko &lt;me@ruff.mobi&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk.kim@samsung.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
