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<title>linux.git/fs/ext4, branch v2.6.31</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4</title>
<updated>2009-07-13T23:39:25+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2009-07-13T23:39:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1cf29683f4414296dc772a87caa207cab16c310c'/>
<id>1cf29683f4414296dc772a87caa207cab16c310c</id>
<content type='text'>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: fix race between write_metadata_buffer and get_write_access
  ext4: Fix ext4_mb_initialize_context() to initialize all fields
  ext4: fix null handler of ioctls in no journal mode
  ext4: Fix buffer head reference leak in no-journal mode
  ext4: Move __ext4_journalled_writepage() to avoid forward declaration
  ext4: Fix mmap/truncate race when blocksize &lt; pagesize &amp;&amp; !nodellaoc
  ext4: Fix mmap/truncate race when blocksize &lt; pagesize &amp;&amp; delayed allocation
  ext4: Don't look at buffer_heads outside i_size.
  ext4: Fix goal inum check in the inode allocator
  ext4: fix no journal corruption with locale-gen
  ext4: Calculate required journal credits for inserting an extent properly
  ext4: Fix truncation of symlinks after failed write
  jbd2: Fix a race between checkpointing code and journal_get_write_access()
  ext4: Use rcu_barrier() on module unload.
  ext4: naturally align struct ext4_allocation_request
  ext4: mark several more functions in mballoc.c as noinline
  ext4: Fix potential reclaim deadlock when truncating partial block
  jbd2: Remove GFP_ATOMIC kmalloc from inside spinlock critical region
  ext4: Fix type warning on 64-bit platforms in tracing events header
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* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: fix race between write_metadata_buffer and get_write_access
  ext4: Fix ext4_mb_initialize_context() to initialize all fields
  ext4: fix null handler of ioctls in no journal mode
  ext4: Fix buffer head reference leak in no-journal mode
  ext4: Move __ext4_journalled_writepage() to avoid forward declaration
  ext4: Fix mmap/truncate race when blocksize &lt; pagesize &amp;&amp; !nodellaoc
  ext4: Fix mmap/truncate race when blocksize &lt; pagesize &amp;&amp; delayed allocation
  ext4: Don't look at buffer_heads outside i_size.
  ext4: Fix goal inum check in the inode allocator
  ext4: fix no journal corruption with locale-gen
  ext4: Calculate required journal credits for inserting an extent properly
  ext4: Fix truncation of symlinks after failed write
  jbd2: Fix a race between checkpointing code and journal_get_write_access()
  ext4: Use rcu_barrier() on module unload.
  ext4: naturally align struct ext4_allocation_request
  ext4: mark several more functions in mballoc.c as noinline
  ext4: Fix potential reclaim deadlock when truncating partial block
  jbd2: Remove GFP_ATOMIC kmalloc from inside spinlock critical region
  ext4: Fix type warning on 64-bit platforms in tracing events header
</pre>
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</entry>
<entry>
<title>ext4: Fix ext4_mb_initialize_context() to initialize all fields</title>
<updated>2009-07-13T13:45:52+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2009-07-13T13:45:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=833576b362e15c38be3bfe43942cda693e56287c'/>
<id>833576b362e15c38be3bfe43942cda693e56287c</id>
<content type='text'>
Pavel Roskin pointed out that kmemcheck indicated that
ext4_mb_store_history() was accessing uninitialized values of
ac-&gt;ac_tail and ac-&gt;ac_buddy leading to garbage in the mballoc
history.  Fix this by initializing the entire structure to all zeros
first.

Also, two fields were getting doubly initialized by the caller of
ext4_mb_initialize_context, so remove them for efficiency's sake.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
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<pre>
Pavel Roskin pointed out that kmemcheck indicated that
ext4_mb_store_history() was accessing uninitialized values of
ac-&gt;ac_tail and ac-&gt;ac_buddy leading to garbage in the mballoc
history.  Fix this by initializing the entire structure to all zeros
first.

Also, two fields were getting doubly initialized by the caller of
ext4_mb_initialize_context, so remove them for efficiency's sake.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
</pre>
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</content>
</entry>
<entry>
<title>ext4: fix null handler of ioctls in no journal mode</title>
<updated>2009-07-13T13:30:17+00:00</updated>
<author>
<name>Peng Tao</name>
<email>bergwolf@gmail.com</email>
</author>
<published>2009-07-13T13:30:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ac046f1d6121ccdda6db66bd88acd52418f489b2'/>
<id>ac046f1d6121ccdda6db66bd88acd52418f489b2</id>
<content type='text'>
The EXT4_IOC_GROUP_ADD and EXT4_IOC_GROUP_EXTEND ioctls should not
flush the journal in no_journal mode.  Otherwise, running resize2fs on
a mounted no_journal partition triggers the following error messages:

BUG: unable to handle kernel NULL pointer dereference at 00000014
IP: [&lt;c039d282&gt;] _spin_lock+0x8/0x19
*pde = 00000000 
Oops: 0002 [#1] SMP

Signed-off-by: Peng Tao &lt;bergwolf@gmail.com&gt;
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
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<pre>
The EXT4_IOC_GROUP_ADD and EXT4_IOC_GROUP_EXTEND ioctls should not
flush the journal in no_journal mode.  Otherwise, running resize2fs on
a mounted no_journal partition triggers the following error messages:

BUG: unable to handle kernel NULL pointer dereference at 00000014
IP: [&lt;c039d282&gt;] _spin_lock+0x8/0x19
*pde = 00000000 
Oops: 0002 [#1] SMP

Signed-off-by: Peng Tao &lt;bergwolf@gmail.com&gt;
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
</pre>
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</content>
</entry>
<entry>
<title>ext4: Fix buffer head reference leak in no-journal mode</title>
<updated>2009-07-13T13:07:20+00:00</updated>
<author>
<name>Curt Wohlgemuth</name>
<email>curtw@google.com</email>
</author>
<published>2009-07-13T13:07:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e6b5d30104db5f34110678ecab14988f1f1eff63'/>
<id>e6b5d30104db5f34110678ecab14988f1f1eff63</id>
<content type='text'>
We found a problem with buffer head reference leaks when using an ext4
partition without a journal.  In particular, calls to ext4_forget() would
not to a brelse() on the input buffer head, which will cause pages they
belong to to not be reclaimable.

Further investigation showed that all places where ext4_journal_forget() and
ext4_journal_revoke() are called are subject to the same problem.  The patch
below changes __ext4_journal_forget/__ext4_journal_revoke to do an explicit
release of the buffer head when the journal handle isn't valid.

Signed-off-by: Curt Wohlgemuth &lt;curtw@google.com&gt;
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
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<pre>
We found a problem with buffer head reference leaks when using an ext4
partition without a journal.  In particular, calls to ext4_forget() would
not to a brelse() on the input buffer head, which will cause pages they
belong to to not be reclaimable.

Further investigation showed that all places where ext4_journal_forget() and
ext4_journal_revoke() are called are subject to the same problem.  The patch
below changes __ext4_journal_forget/__ext4_journal_revoke to do an explicit
release of the buffer head when the journal handle isn't valid.

Signed-off-by: Curt Wohlgemuth &lt;curtw@google.com&gt;
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
</pre>
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</content>
</entry>
<entry>
<title>headers: smp_lock.h redux</title>
<updated>2009-07-12T19:22:34+00:00</updated>
<author>
<name>Alexey Dobriyan</name>
<email>adobriyan@gmail.com</email>
</author>
<published>2009-07-11T18:08:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=405f55712dfe464b3240d7816cc4fe4174831be2'/>
<id>405f55712dfe464b3240d7816cc4fe4174831be2</id>
<content type='text'>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
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* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
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</content>
</entry>
<entry>
<title>helpers for acl caching + switch to those</title>
<updated>2009-06-24T12:17:07+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2009-06-09T16:11:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=073aaa1b142461d91f83da66db1184d7c1b1edea'/>
<id>073aaa1b142461d91f83da66db1184d7c1b1edea</id>
<content type='text'>
helpers: get_cached_acl(inode, type), set_cached_acl(inode, type, acl),
forget_cached_acl(inode, type).

ubifs/xattr.c needed includes reordered, the rest is a plain switchover.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
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<pre>
helpers: get_cached_acl(inode, type), set_cached_acl(inode, type, acl),
forget_cached_acl(inode, type).

ubifs/xattr.c needed includes reordered, the rest is a plain switchover.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
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</content>
</entry>
<entry>
<title>switch ext4 to inode-&gt;i_acl</title>
<updated>2009-06-24T12:17:04+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2009-06-08T23:54:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d4bfe2f76d785cc77611a4bda8cedaff358d8c7d'/>
<id>d4bfe2f76d785cc77611a4bda8cedaff358d8c7d</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
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<pre>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
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</content>
</entry>
<entry>
<title>Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block</title>
<updated>2009-06-20T00:43:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2009-06-20T00:43:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=31583d6acf940d2951bc8716557b06d9de5a0c4b'/>
<id>31583d6acf940d2951bc8716557b06d9de5a0c4b</id>
<content type='text'>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Fix kernel-doc parameter name typo in blk-settings.c:
  block: rename CONFIG_LBD to CONFIG_LBDAF
  block: Fix bounce_pfn setting
  hd: stop defining MAJOR_NR
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* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Fix kernel-doc parameter name typo in blk-settings.c:
  block: rename CONFIG_LBD to CONFIG_LBDAF
  block: Fix bounce_pfn setting
  hd: stop defining MAJOR_NR
</pre>
</div>
</content>
</entry>
<entry>
<title>block: rename CONFIG_LBD to CONFIG_LBDAF</title>
<updated>2009-06-19T06:08:50+00:00</updated>
<author>
<name>Bartlomiej Zolnierkiewicz</name>
<email>bzolnier@gmail.com</email>
</author>
<published>2009-06-19T06:08:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=90c699a9ee4be165966d40f1837909ccb8890a68'/>
<id>90c699a9ee4be165966d40f1837909ccb8890a68</id>
<content type='text'>
Follow-up to "block: enable by default support for large devices
and files on 32-bit archs".

Rename CONFIG_LBD to CONFIG_LBDAF to:
- allow update of existing [def]configs for "default y" change
- reflect that it is used also for large files support nowadays

Signed-off-by: Bartlomiej Zolnierkiewicz &lt;bzolnier@gmail.com&gt;
Signed-off-by: Jens Axboe &lt;jens.axboe@oracle.com&gt;
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<pre>
Follow-up to "block: enable by default support for large devices
and files on 32-bit archs".

Rename CONFIG_LBD to CONFIG_LBDAF to:
- allow update of existing [def]configs for "default y" change
- reflect that it is used also for large files support nowadays

Signed-off-by: Bartlomiej Zolnierkiewicz &lt;bzolnier@gmail.com&gt;
Signed-off-by: Jens Axboe &lt;jens.axboe@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ext4: avoid unnecessary spinlock in critical POSIX ACL path</title>
<updated>2009-06-17T04:36:35+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2009-06-08T19:22:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=210ad6aedb332e73167ece5af9bd47f0da8c2aca'/>
<id>210ad6aedb332e73167ece5af9bd47f0da8c2aca</id>
<content type='text'>
If a filesystem supports POSIX ACL's, the VFS layer expects the filesystem
to do POSIX ACL checks on any files not owned by the caller, and it does
this for every single pathname component that it looks up.

That obviously can be pretty expensive if the filesystem isn't careful
about it, especially with locking. That's doubly sad, since the common
case tends to be that there are no ACL's associated with the files in
question.

ext4 already caches the ACL data so that it doesn't have to look it up
over and over again, but it does so by taking the inode-&gt;i_lock spinlock
on every lookup. Which is a noticeable overhead even if it's a private
lock, especially on CPU's where the serialization is expensive (eg Intel
Netburst aka 'P4').

For the special case of not actually having any ACL's, all that locking is
unnecessary. Even if somebody else were to be changing the ACL's on
another CPU, we simply don't care - if we've seen a NULL ACL, we might as
well use it.

So just load the ACL speculatively without any locking, and if it was
NULL, just use it. If it's non-NULL (either because we had a cached
entry, or because the cache hasn't been filled in at all), it means that
we'll need to get the lock and re-load it properly.

(This commit was ported from a patch originally authored by Linus for
ext3.)

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
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<pre>
If a filesystem supports POSIX ACL's, the VFS layer expects the filesystem
to do POSIX ACL checks on any files not owned by the caller, and it does
this for every single pathname component that it looks up.

That obviously can be pretty expensive if the filesystem isn't careful
about it, especially with locking. That's doubly sad, since the common
case tends to be that there are no ACL's associated with the files in
question.

ext4 already caches the ACL data so that it doesn't have to look it up
over and over again, but it does so by taking the inode-&gt;i_lock spinlock
on every lookup. Which is a noticeable overhead even if it's a private
lock, especially on CPU's where the serialization is expensive (eg Intel
Netburst aka 'P4').

For the special case of not actually having any ACL's, all that locking is
unnecessary. Even if somebody else were to be changing the ACL's on
another CPU, we simply don't care - if we've seen a NULL ACL, we might as
well use it.

So just load the ACL speculatively without any locking, and if it was
NULL, just use it. If it's non-NULL (either because we had a cached
entry, or because the cache hasn't been filled in at all), it means that
we'll need to get the lock and re-load it properly.

(This commit was ported from a patch originally authored by Linus for
ext3.)

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
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