<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/fs/fat/inode.c, branch v3.0.29</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>fat: Fix statfs-&gt;f_namelen</title>
<updated>2011-04-12T12:12:50+00:00</updated>
<author>
<name>OGAWA Hirofumi</name>
<email>hirofumi@mail.parknet.co.jp</email>
</author>
<published>2011-04-12T12:08:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f68e542f3478147986a9c8958942ec649dc06201'/>
<id>f68e542f3478147986a9c8958942ec649dc06201</id>
<content type='text'>
pathconf(, _PC_NAME_MAX) is too small for long Unicode filename on fat.

255 as max filename size on fat is Unicode UTF-16 characters.
it's not byte size.

https://bugzilla.kernel.org/show_bug.cgi?id=16469

To fix it, this returns "len * NLS_MAX_CHARSET_SIZE" instead.

Reported-by: Takumi Asaki &lt;takumi.asaki@nokia.com&gt;
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
pathconf(, _PC_NAME_MAX) is too small for long Unicode filename on fat.

255 as max filename size on fat is Unicode UTF-16 characters.
it's not byte size.

https://bugzilla.kernel.org/show_bug.cgi?id=16469

To fix it, this returns "len * NLS_MAX_CHARSET_SIZE" instead.

Reported-by: Takumi Asaki &lt;takumi.asaki@nokia.com&gt;
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fat: Replace all printk with fat_msg()</title>
<updated>2011-04-12T12:12:42+00:00</updated>
<author>
<name>Alexey Fisher</name>
<email>bug-track@fisher-privat.net</email>
</author>
<published>2011-04-12T12:08:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=869f58c0cdba3ae6880ab6113617e62672198773'/>
<id>869f58c0cdba3ae6880ab6113617e62672198773</id>
<content type='text'>
Replace all printk with fat_msg()

Signed-off-by: Alexey Fisher &lt;bug-track@fisher-privat.net&gt;
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Replace all printk with fat_msg()

Signed-off-by: Alexey Fisher &lt;bug-track@fisher-privat.net&gt;
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fat: use new setup() for -&gt;dir_ops too</title>
<updated>2011-04-12T12:12:00+00:00</updated>
<author>
<name>OGAWA Hirofumi</name>
<email>hirofumi@mail.parknet.co.jp</email>
</author>
<published>2011-04-12T12:08:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=384f5c96ea05aba24a11172ebd6f5d427ca199fc'/>
<id>384f5c96ea05aba24a11172ebd6f5d427ca199fc</id>
<content type='text'>
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block</title>
<updated>2011-03-24T17:16:26+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2011-03-24T17:16:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6c5103890057b1bb781b26b7aae38d33e4c517d8'/>
<id>6c5103890057b1bb781b26b7aae38d33e4c517d8</id>
<content type='text'>
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
  Documentation/iostats.txt: bit-size reference etc.
  cfq-iosched: removing unnecessary think time checking
  cfq-iosched: Don't clear queue stats when preempt.
  blk-throttle: Reset group slice when limits are changed
  blk-cgroup: Only give unaccounted_time under debug
  cfq-iosched: Don't set active queue in preempt
  block: fix non-atomic access to genhd inflight structures
  block: attempt to merge with existing requests on plug flush
  block: NULL dereference on error path in __blkdev_get()
  cfq-iosched: Don't update group weights when on service tree
  fs: assign sb-&gt;s_bdi to default_backing_dev_info if the bdi is going away
  block: Require subsystems to explicitly allocate bio_set integrity mempool
  jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  fs: make fsync_buffers_list() plug
  mm: make generic_writepages() use plugging
  blk-cgroup: Add unaccounted time to timeslice_used.
  block: fixup plugging stubs for !CONFIG_BLOCK
  block: remove obsolete comments for blkdev_issue_zeroout.
  blktrace: Use rq-&gt;cmd_flags directly in blk_add_trace_rq.
  ...

Fix up conflicts in fs/{aio.c,super.c}
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
  Documentation/iostats.txt: bit-size reference etc.
  cfq-iosched: removing unnecessary think time checking
  cfq-iosched: Don't clear queue stats when preempt.
  blk-throttle: Reset group slice when limits are changed
  blk-cgroup: Only give unaccounted_time under debug
  cfq-iosched: Don't set active queue in preempt
  block: fix non-atomic access to genhd inflight structures
  block: attempt to merge with existing requests on plug flush
  block: NULL dereference on error path in __blkdev_get()
  cfq-iosched: Don't update group weights when on service tree
  fs: assign sb-&gt;s_bdi to default_backing_dev_info if the bdi is going away
  block: Require subsystems to explicitly allocate bio_set integrity mempool
  jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  fs: make fsync_buffers_list() plug
  mm: make generic_writepages() use plugging
  blk-cgroup: Add unaccounted time to timeslice_used.
  block: fixup plugging stubs for !CONFIG_BLOCK
  block: remove obsolete comments for blkdev_issue_zeroout.
  blktrace: Use rq-&gt;cmd_flags directly in blk_add_trace_rq.
  ...

Fix up conflicts in fs/{aio.c,super.c}
</pre>
</div>
</content>
</entry>
<entry>
<title>exportfs: Return the minimum required handle size</title>
<updated>2011-03-14T13:15:28+00:00</updated>
<author>
<name>Aneesh Kumar K.V</name>
<email>aneesh.kumar@linux.vnet.ibm.com</email>
</author>
<published>2011-01-29T13:13:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5fe0c2378884e68beb532f5890cc0e3539ac747b'/>
<id>5fe0c2378884e68beb532f5890cc0e3539ac747b</id>
<content type='text'>
The exportfs encode handle function should return the minimum required
handle size. This helps user to find out the handle size by passing 0
handle size in the first step and then redoing to the call again with
the returned handle size value.

Acked-by: Serge Hallyn &lt;serue@us.ibm.com&gt;
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.vnet.ibm.com&gt;
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>
The exportfs encode handle function should return the minimum required
handle size. This helps user to find out the handle size by passing 0
handle size in the first step and then redoing to the call again with
the returned handle size value.

Acked-by: Serge Hallyn &lt;serue@us.ibm.com&gt;
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.vnet.ibm.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: remove per-queue plugging</title>
<updated>2011-03-10T07:52:07+00:00</updated>
<author>
<name>Jens Axboe</name>
<email>jaxboe@fusionio.com</email>
</author>
<published>2011-03-10T07:52:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7eaceaccab5f40bbfda044629a6298616aeaed50'/>
<id>7eaceaccab5f40bbfda044629a6298616aeaed50</id>
<content type='text'>
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops-&gt;sync_page().

Signed-off-by: Jens Axboe &lt;jaxboe@fusionio.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops-&gt;sync_page().

Signed-off-by: Jens Axboe &lt;jaxboe@fusionio.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>switch fat to -&gt;s_d_op, close exportfs races there</title>
<updated>2011-01-13T01:02:43+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2010-12-18T15:44:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3d23985d6cfa7908e46fd0c62a2ee84faffe4d8b'/>
<id>3d23985d6cfa7908e46fd0c62a2ee84faffe4d8b</id>
<content type='text'>
don't bother with lock_super() in fat_fill_super() callers, while
we are at it - there won't be any concurrency anyway.

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>
don't bother with lock_super() in fat_fill_super() callers, while
we are at it - there won't be any concurrency anyway.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: dcache reduce branches in lookup path</title>
<updated>2011-01-07T06:50:28+00:00</updated>
<author>
<name>Nick Piggin</name>
<email>npiggin@kernel.dk</email>
</author>
<published>2011-01-07T06:49:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fb045adb99d9b7c562dc7fef834857f78249daa1'/>
<id>fb045adb99d9b7c562dc7fef834857f78249daa1</id>
<content type='text'>
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry-&gt;d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.&gt;]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)-&gt;d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&amp;\1, \2);/' -i

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry-&gt;d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.&gt;]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)-&gt;d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&amp;\1, \2);/' -i

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: icache RCU free inodes</title>
<updated>2011-01-07T06:50:26+00:00</updated>
<author>
<name>Nick Piggin</name>
<email>npiggin@kernel.dk</email>
</author>
<published>2011-01-07T06:49:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fa0d7e3de6d6fc5004ad9dea0dd6b286af8f03e9'/>
<id>fa0d7e3de6d6fc5004ad9dea0dd6b286af8f03e9</id>
<content type='text'>
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page-&gt;mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page-&gt;mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>BKL: Remove BKL from fat</title>
<updated>2010-10-04T19:10:45+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2010-09-14T21:07:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3768744cfea7b995dce27f02341161fbfdfee80c'/>
<id>3768744cfea7b995dce27f02341161fbfdfee80c</id>
<content type='text'>
The lock_kernel in fat_put_super is not needed because
it only protects the super block itself and we know that
no other thread can reach it because we are about to
kfree the object.

In the two fill_super functions, this converts the locking
to use lock_super like elsewhere in the fat code. This
is probably not needed either, but is consistent and puts
us on the safe side.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
Cc: Jan Blunck &lt;jblunck@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The lock_kernel in fat_put_super is not needed because
it only protects the super block itself and we know that
no other thread can reach it because we are about to
kfree the object.

In the two fill_super functions, this converts the locking
to use lock_super like elsewhere in the fat code. This
is probably not needed either, but is consistent and puts
us on the safe side.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
Cc: Jan Blunck &lt;jblunck@infradead.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
