```-----------------------
while() {
	list_entry();
	...
}
```

-----------------------

is equivalent to following code.

--------------------------
list_for_each_entry(){
	...
}
--------------------------

later can review easily more.

this patch is just clean up.
it doesn't have any behavor change.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ignoring their return values may result in counter underflow in the future -
when the value charged will be uncharged (or in "leaks" - when the value is
not uncharged).

This also prevents from using charging routines to decrement the
counter value (i.e. uncharge it) ;)

(Current code works OK with res_counter, however :) )
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The function does not modify anything (except the temporary css template), so
it's sufficient to hold read lock.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPaul Menage <menage@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Having trailing   entities in a revision numer seems pretty pointless
to me.  More so, it's causing me pains, so just drop them since no other
guide is doing this.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Sometimes it may be useful for userspace to know (e.g.  for some hosting
guys) that some user stopped exceeding his hardlimit or softlimit in
quotas.  Implement sending of such events to userspace via quota netlink
protocol so that they don't have to poll for such events.  Based on idea
and initial implementation by Vladislav Bogdanov.

Cc: Vladislav Bogdanov <slava@nsys.by>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move declarations of some macros, which should be in fact functions to
quotaops.h.  This way they can be later converted to inline functions
because we can now use declarations from quota.h.  Also add necessary
includes of quotaops.h to a few files.

[akpm@linux-foundation.org: fix JFS build]
[akpm@linux-foundation.org: fix UFS build]
[vegard.nossum@gmail.com: fix QUOTA=n build]
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Arjen Pool <arjenpool@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make loop in sync_dquots() checking whether there's something to write
more readable, remove useless variable and macro info_any_dirty() which
is used only in this place.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: "Vegard Nossum" <vegard.nossum@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cleanup quotaops.h: Rename functions from uppercase to lowercase (and
define backward compatibility macros), move larger functions to dquot.c
and make them non-inline.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When quota structure is going to be dropped and it is dirty, quota code tries
to write it.  If the write fails for some reason (e.  g.  transaction cannot
be started because the journal is aborted), we try writing again and again and
again...  Fix the problem by clearing the dirty bit even if the write failed.

(akpm: for 2.6.27, 2.6.26.x and 2.6.25.x)
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: Ndingdinghua <dingdinghua85@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJoe Peterson <joe@skyrush.com>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Provide a new mount option ("tz=UTC") for DOS (vfat/msdos) filesystems,
allowing timestamps to be in coordinated universal time (UTC) rather than
local time in applications where doing this is advantageous.

In particular, portable devices that use fat/vfat (such as digital
cameras) can benefit from using UTC in their internal clocks, thus
avoiding daylight saving time errors and general time ambiguity issues.
The user of the device does not have to worry about changing the time when
moving from place or when daylight saving changes.

The new mount option, when set, disables the counter-adjustment that Linux
currently makes to FAT timestamp info in anticipation of the normal
userspace time zone correction.  When used in this new mode, all daylight
saving time and time zone handling is done in userspace as is normal for
many other filesystems (like ext3).  The default mode, which remains
unchanged, is still appropriate when mounting volumes written in Windows
(because of its use of local time).

I originally based this patch on one submitted last year by Paul Collins,
but I updated it to work with current source and changed variable/option
naming.  Ogawa Hirofumi (who maintains these filesystems) and I discussed
this patch at length on lkml, and he suggested using the option name in
the attached version of the patch.  Barry Bouwsma pointed out a good
addition to the patch as well.
Signed-off-by: NJoe Peterson <joe@skyrush.com>
Signed-off-by: NPaul Collins <paul@ondioline.org>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Barry Bouwsma <free_beer_for_all@yahoo.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove some unused #include <linux/dirent.h>'s.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kernel struct dirent{,64} were different from the ones in
userspace.

Even worse, we exported the kernel ones to userspace.

But after the fat usages are fixed we can remove the conflicting
kernel versions.
Reviewed-by: NH. Peter Anvin <hpa@kernel.org>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It has been impossible to set the option 'atari' of the MSDOS filesystem
for several years.  Since nobody seems to have missed it, let's remove its
remains.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This removes unnecessary parsing for directory entries.

If short_only, we don't need to parse longname.  And if !both and it found
the longname, we don't need shortname.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This uses uses stack for shortname, and uses __getname() for longname in
fat_search_long() and __fat_readdir().  By this, it removes unneeded
__getname() for shortname.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is no logic changes, just cleans fs/fat/dir.c up.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

struct __fat_dirent is what was formerly the kernel struct dirent (that
was different from the userspace struct dirent).

Converting all fat users to struct __fat_dirent will allow us to get rid
of the conflicting struct dirent definition.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"struct dirent" is a kernel type here, but is a **different type** in
userspace!  This means both the structure and the IOCTL number is wrong!

So, this adds new "struct __fat_dirent" to generate correct IOCTL number.
And kernel stuff moves to under __KERNEL__.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Current parse_options() exits too early.  We need to run the code of
bottom in this function even if users doesn't specify options.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

remove the definitions of macros:
XATTR_SECURITY_PREFIX
XATTR_TRUSTED_PREFIX
XATTR_USER_PREFIX
since they are defined in linux/xattr.h
Signed-off-by: NShen Feng <shen@cn.fujitsu.com>
Signed-off-by: NMingming Cao <cmm@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

j_commit_lock is a semaphore but uses it as if it were a mutex.  This patch
converts it to a mutex.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Edward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

j_flush_sem is a semaphore but uses it as if it were a mutex.  This patch
converts it to a mutex.

[akpm@linux-foundation.org: fix mutex_trylock retval treatment]
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Edward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

j_lock is a semaphore but uses it as if it were a mutex.  This patch converts
it to a mutex.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Edward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We should not allow user to change quota mount options when quota is just
suspended.  It would make mount options and internal quota state inconsistent.

Also we should not allow user to change quota format when quota is turned on.
On the other hand we can just silently ignore when some option is set to the
value it already has (some mount versions do this on remount).  Finally, we
should not discard current quota options if parsing of mount options fails.

Cc: <reiserfs-devel@vger.kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: <reiserfs-devel@vger.kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In journal=data mode, it is not enough to do write_inode_now() as done in
vfs_quota_on() to write all data to their final location (which is needed for
quota_read to work correctly).  Calling journal_end_sync() before calling
vfs_quota_on() does it's job because transactions are committed to the journal
and data marked as dirty in memory so write_inode_now() writes them to their
final locations.

Cc: <reiserfs-devel@vger.kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Apple Extended HFS file system: The semaphore extents lock is used as a
mutex.  Convert it to the mutex API.
Signed-off-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Apple Macintosh file system: The semaphore extens_lock is used as a mutex.
Convert it to the mutex API
Signed-off-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Apple Macintosh file system: The semaphore bitmap_lock is used as a mutex.
Convert it to the mutex API
Signed-off-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While fixing CONFIG_ leakages to the userspace kernel headers I ran into
CODA_FS_OLD_API.

After five years, are there still people using the old API left?
Especially considering that you have to choose at compile time which API
to support in the kernel (and distributions tend to offer the new API for
some time).

Jan: "The old API can definitely go.  Around the time the new
      interface went in there were some non-Coda userspace file system
      implementations that took a while longer to convert to the new API,
      but by now they all switched to the new interface or in some cases
      to a FUSE-based solution."
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Acked-by: NJan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some iso9660 images contain files with rockridge data that is either
incorrect or incompletely parsed.  Prior to commit
f2966632 ("[PATCH] rock: handle directory
overflows") (included with kernel 2.6.13) the kernel ignored the rockridge
data for these files, while still allowing the files to be accessed under
their non-rockridge names.  That commit inadvertently changed things so
that files with invalid rockridge data could not be accessed at all.  (I
ran across the problem when comparing some old CDs with hard disk copies I
had made long ago under kernel 2.4: a few of the files on the hard disk
copies were no longer visible on the CDs.)

This change reverts to the pre-2.6.13 behavior.
Signed-off-by: NAdam Greenblatt <adam.greenblatt@gmail.com>
Reviewed-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ext3_dx_find_entry uses ext3_next_entry without verifying that the entry
is valid.  If its rec_len == 0 this causes an infinite loop.  Refactor the
loop to check the validity of entries before checking whether they match
and moving onto the next one.

There are other uses of ext3_next_entry in this file which also look
problematic.  They should be reviewed and fixed if/when we have a
test-case that triggers them.

This patch fixes the first case (image hdb.25.softlockup.gz) reported in
http://bugzilla.kernel.org/show_bug.cgi?id=10882.
Signed-off-by: NDuane Griffin <duaneg@dghda.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ordered mode, the current jbd aborts the journal if a file data buffer
has an error.  But this behavior is unintended, and we found that it has
been adopted accidentally.

This patch undoes it and just calls printk() instead of aborting the
journal.  Additionally, set AS_EIO into the address_space object of the
failed buffer which is submitted by journal_do_submit_data() so that
fsync() can get -EIO.

Missing error checkings are also added to inform errors on file data
buffers to the user.  The following buffers are targeted.

  (a) the buffer which has already been written out by pdflush
  (b) the buffer which has been unlocked before scanned in the
      t_locked_list loop

[akpm@linux-foundation.org: improve grammar in a printk]
Signed-off-by: NHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: NJan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dx_root_limit() will never return 20, and I can't figure out what 20
stands for.  This function has never changed since htree directory
indexing was merged.

Similar for dx_node_limit() and the magic 22.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NAndreas Dilger <adilger@sun.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After ext3-ordered files are truncated, there is a possibility that the
pages which cannot be estimated still remain.  Remaining pages can be
released when the system has really few memory.  So, it is not memory
leakage.  But the resource management software etc.  may not work
correctly.

It is possible that journal_unmap_buffer() cannot release the buffers, and
the pages to which they belong because they are attached to a commiting
transaction and journal_unmap_buffer() cannot release them.  To release
such the buffers and the pages later, journal_unmap_buffer() leaves it to
journal_commit_transaction().  (journal_unmap_buffer() puts the mark
'BH_Freed' to the buffers so that journal_commit_transaction() can
identify whether they can be released or not.)

In the journalled mode and the writeback mode, jbd does with only metadata
buffers.  But in the ordered mode, jbd does with metadata buffers and also
data buffers.

Actually, journal_commit_transaction() releases only the metadata buffers
of which release is demanded by journal_unmap_buffer(), and also releases
the pages to which they belong if possible.

As a result, the data buffers of which release is demanded by
journal_unmap_buffer() remain after a transaction commits.  And also the
pages to which they belong remain.

Such the remained pages don't have mapping any longer.  Due to this fact,
there is a possibility that the pages which cannot be estimated remain.

The metadata buffers marked 'BH_Freed' and the pages to which
they belong can be released at 'JBD: commit phase 7'.

Therefore, by applying the same code into 'JBD: commit phase 2' (where the
data buffers are done with), journal_commit_transaction() can also release
the data buffers marked 'BH_Freed' and the pages to which they belong.

As a result, all the buffers marked 'BH_Freed' can be released, and also
all the pages to which these buffers belong can be released at
journal_commit_transaction().  So, the page which cannot be estimated is
lost.

<<Excerpt of code at 'JBD: commit phase 7'>>
 >         spin_lock(&journal->j_list_lock);
 >         while (commit_transaction->t_forget) {
 >                 transaction_t *cp_transaction;
 >                 struct buffer_head *bh;
 >
 >                 jh = commit_transaction->t_forget;
 >...
 >                 if (buffer_freed(bh)) {
 >                 ^^^^^^^^^^^^^^^^^^^^^^^^
 >                         clear_buffer_freed(bh);
 >                        ^^^^^^^^^^^^^^^^^^^^^^^^
 >                         clear_buffer_jbddirty(bh);
 >                 }
 >
 >                 if (buffer_jbddirty(bh)) {
 >                         JBUFFER_TRACE(jh, "add to new checkpointing trans");
 >                         __journal_insert_checkpoint(jh, commit_transaction);
 >                         JBUFFER_TRACE(jh, "refile for checkpoint writeback");
 >                         __journal_refile_buffer(jh);
 >                         jbd_unlock_bh_state(bh);
 >                 } else {
 >                         J_ASSERT_BH(bh, !buffer_dirty(bh));
 > ...
 >                         JBUFFER_TRACE(jh, "refile or unfile freed buffer");
 >                         __journal_refile_buffer(jh);
 >                         if (!jh->b_transaction) {
 >                                 jbd_unlock_bh_state(bh);
 >                                  /* needs a brelse */
 >                                 journal_remove_journal_head(bh);
 >                                 release_buffer_page(bh);
 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^
 >                         } else
 >                 }
****************************************************************
* Apply the code of "^^^^^^" lines into 'JBD: commit phase 2' *
****************************************************************

At journal_commit_transaction() code, there is one extra message in the
series of jbd debug messages.  ("JBD: commit phase 2") This patch fixes
it, too.
Signed-off-by: NToshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Acked-by: NJan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the unused EXPORT_SYMBOL(journal_update_superblock).
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While freeing indirect blocks we attach a journal head to the parent
buffer head, free the blocks, then journal the parent.  If the indirect
block list is corrupted and points to the parent the journal head will be
detached when the block is cleared, causing an OOPS.

Check for that explicitly and handle it gracefully.

This patch fixes the third case (image hdb.20000057.nullderef.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.

Immediately above the change, in the ext3_free_data function, we call
ext3_clear_blocks to clear the indirect blocks in this parent block.  If
one of those blocks happens to actually be the parent block it will clear
b_private / BH_JBD.

I did the check at the end rather than earlier as it seemed more elegant.
I don't think there should be much practical difference, although it is
possible the FS may not be quite so badly corrupted if we did it the other
way (and didn't clear the block at all).  To be honest, I'm not convinced
there aren't other similar failure modes lurking in this code, although I
couldn't find any with a quick review.

[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: NDuane Griffin <duaneg@dghda.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A transient I/O error can corrupt inode data.  Here is the scenario:

(1) update inode_A at the block_B
(2) pdflush writes out new inode_A to the filesystem, but it results
    in write I/O error, at this point, BH_Uptodate flag of the buffer
    for block_B is cleared and BH_Write_EIO is set
(3) create new inode_C which located at block_B, and
    __ext3_get_inode_loc() tries to read on-disk block_B because the
    buffer is not uptodate
(4) if it can read on-disk block_B successfully, inode_A is
    overwritten by old data

This patch makes __ext3_get_inode_loc() not read the inode block if the
buffer has BH_Write_EIO flag.  In this case, the buffer should have the
latest information, so setting the uptodate flag to the buffer (this
avoids WARN_ON_ONCE() in mark_buffer_dirty().)

According to this change, we would need to test BH_Write_EIO flag for the
error checking.  Currently nobody checks write I/O errors on metadata
buffers, but it will be done in other patches I'm working on.
Signed-off-by: NHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: sugita <yumiko.sugita.yf@hitachi.com>
Cc: Satoshi OSHIMA <satoshi.oshima.fk@hitachi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Jan Kara <jack@ucw.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>