In the past, ext4_calc_metadata_amount(), and its sub-functions
ext4_ext_calc_metadata_amount() and ext4_indirect_calc_metadata_amount()
badly over-estimated the number of metadata blocks that might be
required for delayed allocation blocks.  This didn't matter as much
when functions which managed the reserved metadata blocks were more
aggressive about dropping reserved metadata blocks as delayed
allocation blocks were written, but unfortunately they were too
aggressive.  This was fixed in commit 0637c6f4, but as a result the
over-estimation by ext4_calc_metadata_amount() would lead to reserving
2-3 times the number of pending delayed allocation blocks as
potentially required metadata blocks.  So if there are 1 megabytes of
blocks which have been not yet been allocation, up to 3 megabytes of
space would get reserved out of the user's quota and from the file
system free space pool until all of the inode's data blocks have been
allocated.

This commit addresses this problem by much more accurately estimating
the number of metadata blocks that will be required.  It will still
somewhat over-estimate the number of blocks needed, since it must make
a worst case estimate not knowing which physical blocks will be
needed, but it is much more accurate than before.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Commit 0637c6f4 had a typo which caused the reserved metadata blocks to
not be released correctly.   Fix this.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

As reported in Kernel Bugzilla #14936, commit d21cd8f1 triggered a BUG
in the function ext4_da_update_reserve_space() found in
fs/ext4/inode.c.  The root cause of this BUG() was caused by the fact
that ext4_calc_metadata_amount() can severely over-estimate how many
metadata blocks will be needed, especially when using direct
block-mapped files.

In addition, it can also badly *under* estimate how much space is
needed, since ext4_calc_metadata_amount() assumes that the blocks are
contiguous, and this is not always true.  If the application is
writing blocks to a sparse file, the number of metadata blocks
necessary can be severly underestimated by the functions
ext4_da_reserve_space(), ext4_da_update_reserve_space() and
ext4_da_release_space().  This was the cause of the dq_claim_space
reports found on kerneloops.org.

Unfortunately, doing this right means that we need to massively
over-estimate the amount of free space needed.  So in some cases we
may need to force the inode to be written to disk asynchronously in
to avoid spurious quota failures.

http://bugzilla.kernel.org/show_bug.cgi?id=14936Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This fixes a bug (found by Curt Wohlgemuth) in which new blocks
returned from an extent created with ext4_ext_zeroout() can have dirty
metadata still associated with them.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When ext4_da_writepages increases the nr_to_write in writeback_control
then it must always re-base the return value.  Originally there was a
(misguided) attempt prevent wbc.nr_to_write from going negative.  In
fact, it's necessary to allow nr_to_write to be negative so that
wb_writeback() can correctly calculate how many pages were actually
written.  
Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

It triggers the warning in get_page_from_freelist(), and it isn't
appropriate to use __GFP_NOFAIL here anyway.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=14843Reported-by: NChristian Casteyde <casteyde.christian@free.fr>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Creating many small files in rapid succession on a small
filesystem can lead to spurious ENOSPC; on a 104MB filesystem:

for i in `seq 1 22500`; do
    echo -n > $SCRATCH_MNT/$i
    echo XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX > $SCRATCH_MNT/$i
done

leads to ENOSPC even though after a sync, 40% of the fs is free
again.

This is because we reserve worst-case metadata for delalloc writes,
and when data is allocated that worst-case reservation is not
usually needed.

When freespace is low, kicking off an async writeback will start
converting that worst-case space usage into something more realistic,
almost always freeing up space to continue.

This resolves the testcase for me, and survives all 4 generic
ENOSPC tests in xfstests.

We'll still need a hard synchronous sync to squeeze out the last bit,
but this fixes things up to a large degree.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

ext4, at least, would like to start pushing on writeback if it starts
to get close to ENOSPC when reserving worst-case blocks for delalloc
writes.  Writing out delalloc data will convert those worst-case
predictions into usually smaller actual usage, freeing up space
before we hit ENOSPC based on this speculation.

Thanks to Jens for the suggestion for the helper function,
& the naming help.

I've made the helper return status on whether writeback was
started even though I don't plan to use it in the ext4 patch;
it seems like it would be potentially useful to test this
in some cases.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Acked-by: NJan Kara <jack@suse.cz>

b_entry_name and buffer are initially NULL, are initialized within a loop
to the result of calling kmalloc, and are freed at the bottom of this loop.
The loop contains gotos to cleanup, which also frees b_entry_name and
buffer.  Some of these gotos are before the reinitializations of
b_entry_name and buffer.  To maintain the invariant that b_entry_name and
buffer are NULL at the top of the loop, and thus acceptable arguments to
kfree, these variables are now set to NULL after the kfrees.

This seems to be the simplest solution.  A more complicated solution
would be to introduce more labels in the error handling code at the end of
the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
identifier E;
expression E1;
iterator I;
statement S;
@@

*kfree(E);
... when != E = E1
    when != I(E,...) S
    when != &E
*kfree(E);
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

sparc64 allmodconfig:

fs/ext4/super.c: In function `lifetime_write_kbytes_show':
fs/ext4/super.c:2174: warning: long long unsigned int format, long unsigned int arg (arg 4)
fs/ext4/super.c:2174: warning: long long unsigned int format, long unsigned int arg (arg 4)
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This is a bit complicated because we are trying to optimize when we
send barriers to the fs data disk.  We could just throw in an extra
barrier to the data disk whenever we send a barrier to the journal
disk, but that's not always strictly necessary.

We only need to send a barrier during a commit when there are data
blocks which are must be written out due to an inode written in
ordered mode, or if fsync() depends on the commit to force data blocks
to disk.  Finally, before we drop transactions from the beginning of
the journal during a checkpoint operation, we need to guarantee that
any blocks that were flushed out to the data disk are firmly on the
rust platter before we drop the transaction from the journal.

Thanks to Oleg Drokin for pointing out this flaw in ext3/ext4.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This patch fixes the Kernel BZ #14286.  When the address of an extent
corresponding to a valid block is corrupted, a -EIO should be reported
instead of a BUG().  This situation should not normally not occur
except in the case of a corrupted filesystem.  If however it does,
then the system should not panic directly but depending on the mount
time options appropriate action should be taken. If the mount options
so permit, the I/O should be gracefully aborted by returning a -EIO.

http://bugzilla.kernel.org/show_bug.cgi?id=14286Signed-off-by: NSurbhi Palande <surbhi.palande@canonical.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add module aliases for ext2 and ext3 when CONFIG_EXT4_USE_FOR_EXT23 is
set.  This makes the existing user-space stuff like mkinitrd working
as is.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Don't offer to build ext2/3 support into ext4 if ext4 itself is not
configured on.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Remove unused #include <linux/version.h>('s) in
  fs/ext4/block_validity.c
  fs/ext4/mballoc.h
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

In ocfs2_value_metas_in_xattr_header, we should Use
le16_to_cpu for ocfs2_extent_list.l_next_free_rec.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

I just noticed today that there are 2 places of "mlog(0,...)"
in  fs/ocfs2/cluster/heartbeat.c, but actually have no default
mask prefix in that file.
So change them to mlog(ML_HEARTBEAT,...).
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

For fast symlink, it can be treated the same as inlined files since
the data extent we want to return of both case all were stored in
metadata block. For symlink, it can be simply treated the same as we
did for regular files.
Signed-off-by: NTristan Ye <tristan.ye@oracle.com>
Acked-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Many struct bin_attribute descriptors are purely read-only
structures, and there's no need to change them. Therefore
make the promise not to, which will let those descriptors
be put in a ro section.
Signed-off-by: NPhil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Filesystem code usually destroys the option buffer while
parsing it. This leads to errors when the same buffer is
passed twice. In case we fill a new superblock do not call
remount.

This is needed to quite a warning that the debugfs code
causes every boot.

Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When we are asked for vfsv0 quota format and the file is in vfsv1
format (or vice versa), refuse to use the quota file. Also return
with error when we don't like the header of quota file.
Signed-off-by: NJan Kara <jack@suse.cz>

jbd-debug and jbd2-debug is currently read-only (S_IRUGO), which is not
correct. Make it writable so that we can start debuging.
Signed-off-by: NYin Kangkai <kangkai.yin@intel.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Unlock i_block_reservation_lock before vfs_dq_reserve_block().
This patch fixes http://bugzilla.kernel.org/show_bug.cgi?id=14739

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

We have to delay vfs_dq_claim_space() until allocation context destruction.
Currently we have following call-trace:
ext4_mb_new_blocks()
  /* task is already holding ac->alloc_semp */
 ->ext4_mb_mark_diskspace_used
    ->vfs_dq_claim_space()  /*  acquire dqptr_sem here. Possible deadlock */
 ->ext4_mb_release_context() /* drop ac->alloc_semp here */

Let's move quota claiming to ext4_da_update_reserve_space()

 =======================================================
 [ INFO: possible circular locking dependency detected ]
 2.6.32-rc7 #18
 -------------------------------------------------------
 write-truncate-/3465 is trying to acquire lock:
  (&s->s_dquot.dqptr_sem){++++..}, at: [<c025e73b>] dquot_claim_space+0x3b/0x1b0

 but task is already holding lock:
  (&meta_group_info[i]->alloc_sem){++++..}, at: [<c02ce962>] ext4_mb_load_buddy+0xb2/0x370

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #3 (&meta_group_info[i]->alloc_sem){++++..}:
        [<c017d04b>] __lock_acquire+0xd7b/0x1260
        [<c017d5ea>] lock_acquire+0xba/0xd0
        [<c0527191>] down_read+0x51/0x90
        [<c02ce962>] ext4_mb_load_buddy+0xb2/0x370
        [<c02d0c1c>] ext4_mb_free_blocks+0x46c/0x870
        [<c029c9d3>] ext4_free_blocks+0x73/0x130
        [<c02c8cfc>] ext4_ext_truncate+0x76c/0x8d0
        [<c02a8087>] ext4_truncate+0x187/0x5e0
        [<c01e0f7b>] vmtruncate+0x6b/0x70
        [<c022ec02>] inode_setattr+0x62/0x190
        [<c02a2d7a>] ext4_setattr+0x25a/0x370
        [<c022ee81>] notify_change+0x151/0x340
        [<c021349d>] do_truncate+0x6d/0xa0
        [<c0221034>] may_open+0x1d4/0x200
        [<c022412b>] do_filp_open+0x1eb/0x910
        [<c021244d>] do_sys_open+0x6d/0x140
        [<c021258e>] sys_open+0x2e/0x40
        [<c0103100>] sysenter_do_call+0x12/0x32

 -> #2 (&ei->i_data_sem){++++..}:
        [<c017d04b>] __lock_acquire+0xd7b/0x1260
        [<c017d5ea>] lock_acquire+0xba/0xd0
        [<c0527191>] down_read+0x51/0x90
        [<c02a5787>] ext4_get_blocks+0x47/0x450
        [<c02a74c1>] ext4_getblk+0x61/0x1d0
        [<c02a7a7f>] ext4_bread+0x1f/0xa0
        [<c02bcddc>] ext4_quota_write+0x12c/0x310
        [<c0262d23>] qtree_write_dquot+0x93/0x120
        [<c0261708>] v2_write_dquot+0x28/0x30
        [<c025d3fb>] dquot_commit+0xab/0xf0
        [<c02be977>] ext4_write_dquot+0x77/0x90
        [<c02be9bf>] ext4_mark_dquot_dirty+0x2f/0x50
        [<c025e321>] dquot_alloc_inode+0x101/0x180
        [<c029fec2>] ext4_new_inode+0x602/0xf00
        [<c02ad789>] ext4_create+0x89/0x150
        [<c0221ff2>] vfs_create+0xa2/0xc0
        [<c02246e7>] do_filp_open+0x7a7/0x910
        [<c021244d>] do_sys_open+0x6d/0x140
        [<c021258e>] sys_open+0x2e/0x40
        [<c0103100>] sysenter_do_call+0x12/0x32

 -> #1 (&sb->s_type->i_mutex_key#7/4){+.+...}:
        [<c017d04b>] __lock_acquire+0xd7b/0x1260
        [<c017d5ea>] lock_acquire+0xba/0xd0
        [<c0526505>] mutex_lock_nested+0x65/0x2d0
        [<c0260c9d>] vfs_load_quota_inode+0x4bd/0x5a0
        [<c02610af>] vfs_quota_on_path+0x5f/0x70
        [<c02bc812>] ext4_quota_on+0x112/0x190
        [<c026345a>] sys_quotactl+0x44a/0x8a0
        [<c0103100>] sysenter_do_call+0x12/0x32

 -> #0 (&s->s_dquot.dqptr_sem){++++..}:
        [<c017d361>] __lock_acquire+0x1091/0x1260
        [<c017d5ea>] lock_acquire+0xba/0xd0
        [<c0527191>] down_read+0x51/0x90
        [<c025e73b>] dquot_claim_space+0x3b/0x1b0
        [<c02cb95f>] ext4_mb_mark_diskspace_used+0x36f/0x380
        [<c02d210a>] ext4_mb_new_blocks+0x34a/0x530
        [<c02c83fb>] ext4_ext_get_blocks+0x122b/0x13c0
        [<c02a5966>] ext4_get_blocks+0x226/0x450
        [<c02a5ff3>] mpage_da_map_blocks+0xc3/0xaa0
        [<c02a6ed6>] ext4_da_writepages+0x506/0x790
        [<c01de272>] do_writepages+0x22/0x50
        [<c01d766d>] __filemap_fdatawrite_range+0x6d/0x80
        [<c01d7b9b>] filemap_flush+0x2b/0x30
        [<c02a40ac>] ext4_alloc_da_blocks+0x5c/0x60
        [<c029e595>] ext4_release_file+0x75/0xb0
        [<c0216b59>] __fput+0xf9/0x210
        [<c0216c97>] fput+0x27/0x30
        [<c02122dc>] filp_close+0x4c/0x80
        [<c014510e>] put_files_struct+0x6e/0xd0
        [<c01451b7>] exit_files+0x47/0x60
        [<c0146a24>] do_exit+0x144/0x710
        [<c0147028>] do_group_exit+0x38/0xa0
        [<c0159abc>] get_signal_to_deliver+0x2ac/0x410
        [<c0102849>] do_notify_resume+0xb9/0x890
        [<c01032d2>] work_notifysig+0x13/0x21

 other info that might help us debug this:

 3 locks held by write-truncate-/3465:
  #0:  (jbd2_handle){+.+...}, at: [<c02e1f8f>] start_this_handle+0x38f/0x5c0
  #1:  (&ei->i_data_sem){++++..}, at: [<c02a57f6>] ext4_get_blocks+0xb6/0x450
  #2:  (&meta_group_info[i]->alloc_sem){++++..}, at: [<c02ce962>] ext4_mb_load_buddy+0xb2/0x370

 stack backtrace:
 Pid: 3465, comm: write-truncate- Not tainted 2.6.32-rc7 #18
 Call Trace:
  [<c0524cb3>] ? printk+0x1d/0x22
  [<c017ac9a>] print_circular_bug+0xca/0xd0
  [<c017d361>] __lock_acquire+0x1091/0x1260
  [<c016bca2>] ? sched_clock_local+0xd2/0x170
  [<c0178fd0>] ? trace_hardirqs_off_caller+0x20/0xd0
  [<c017d5ea>] lock_acquire+0xba/0xd0
  [<c025e73b>] ? dquot_claim_space+0x3b/0x1b0
  [<c0527191>] down_read+0x51/0x90
  [<c025e73b>] ? dquot_claim_space+0x3b/0x1b0
  [<c025e73b>] dquot_claim_space+0x3b/0x1b0
  [<c02cb95f>] ext4_mb_mark_diskspace_used+0x36f/0x380
  [<c02d210a>] ext4_mb_new_blocks+0x34a/0x530
  [<c02c601d>] ? ext4_ext_find_extent+0x25d/0x280
  [<c02c83fb>] ext4_ext_get_blocks+0x122b/0x13c0
  [<c016bca2>] ? sched_clock_local+0xd2/0x170
  [<c016be60>] ? sched_clock_cpu+0x120/0x160
  [<c016beef>] ? cpu_clock+0x4f/0x60
  [<c0178fd0>] ? trace_hardirqs_off_caller+0x20/0xd0
  [<c052712c>] ? down_write+0x8c/0xa0
  [<c02a5966>] ext4_get_blocks+0x226/0x450
  [<c016be60>] ? sched_clock_cpu+0x120/0x160
  [<c016beef>] ? cpu_clock+0x4f/0x60
  [<c017908b>] ? trace_hardirqs_off+0xb/0x10
  [<c02a5ff3>] mpage_da_map_blocks+0xc3/0xaa0
  [<c01d69cc>] ? find_get_pages_tag+0x16c/0x180
  [<c01d6860>] ? find_get_pages_tag+0x0/0x180
  [<c02a73bd>] ? __mpage_da_writepage+0x16d/0x1a0
  [<c01dfc4e>] ? pagevec_lookup_tag+0x2e/0x40
  [<c01ddf1b>] ? write_cache_pages+0xdb/0x3d0
  [<c02a7250>] ? __mpage_da_writepage+0x0/0x1a0
  [<c02a6ed6>] ext4_da_writepages+0x506/0x790
  [<c016beef>] ? cpu_clock+0x4f/0x60
  [<c016bca2>] ? sched_clock_local+0xd2/0x170
  [<c016be60>] ? sched_clock_cpu+0x120/0x160
  [<c016be60>] ? sched_clock_cpu+0x120/0x160
  [<c02a69d0>] ? ext4_da_writepages+0x0/0x790
  [<c01de272>] do_writepages+0x22/0x50
  [<c01d766d>] __filemap_fdatawrite_range+0x6d/0x80
  [<c01d7b9b>] filemap_flush+0x2b/0x30
  [<c02a40ac>] ext4_alloc_da_blocks+0x5c/0x60
  [<c029e595>] ext4_release_file+0x75/0xb0
  [<c0216b59>] __fput+0xf9/0x210
  [<c0216c97>] fput+0x27/0x30
  [<c02122dc>] filp_close+0x4c/0x80
  [<c014510e>] put_files_struct+0x6e/0xd0
  [<c01451b7>] exit_files+0x47/0x60
  [<c0146a24>] do_exit+0x144/0x710
  [<c017b163>] ? lock_release_holdtime+0x33/0x210
  [<c0528137>] ? _spin_unlock_irq+0x27/0x30
  [<c0147028>] do_group_exit+0x38/0xa0
  [<c017babb>] ? trace_hardirqs_on+0xb/0x10
  [<c0159abc>] get_signal_to_deliver+0x2ac/0x410
  [<c0102849>] do_notify_resume+0xb9/0x890
  [<c0178fd0>] ? trace_hardirqs_off_caller+0x20/0xd0
  [<c017b163>] ? lock_release_holdtime+0x33/0x210
  [<c0165b50>] ? autoremove_wake_function+0x0/0x50
  [<c017ba54>] ? trace_hardirqs_on_caller+0x134/0x190
  [<c017babb>] ? trace_hardirqs_on+0xb/0x10
  [<c0300ba4>] ? security_file_permission+0x14/0x20
  [<c0215761>] ? vfs_write+0x131/0x190
  [<c0214f50>] ? do_sync_write+0x0/0x120
  [<c0103115>] ? sysenter_do_call+0x27/0x32
  [<c01032d2>] work_notifysig+0x13/0x21

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Fix warnings:
fs/quota/quota_v2.c: In function ‘v2_read_file_info’:
fs/quota/quota_v2.c:123: warning: integer constant is too large for ‘long’ type
fs/quota/quota_v2.c:124: warning: integer constant is too large for ‘long’ type
Reported-by: NJerry Leo <jerryleo860202@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Use a separate lock to protect s_groups_count and the other block
group descriptors which get changed via an on-line resize operation,
so we can stop overloading the use of lock_super().

Port of ext4 commit 32ed5058 by
Theodore Ts'o <tytso@mit.edu>.

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Use a separate lock to protect the orphan list, so we can stop
overloading the use of lock_super().

Port of ext4 commit 3b9d4ed2
by Theodore Ts'o <tytso@mit.edu>.

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

The function ext3_mark_recovery_complete() is called from two call
paths: either (a) while mounting the filesystem, in which case there's
no danger of any other CPU calling write_super() until the mount is
completed, and (b) while remounting the filesystem read-write, in
which case the fs core has already locked the superblock.  This also
allows us to take out a very vile unlock_super()/lock_super() pair in
ext3_remount().

Port of ext4 commit a63c9eb2 by
Theodore Ts'o <tytso@mit.edu>.

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

ext3_fill_super() is no longer called by read_super(), and it is no
longer called with the superblock locked.  The
unlock_super()/lock_super() is no longer present, so this comment is
entirely superfluous.

Port of ext4 commit 32ed5058 by
Theodore Ts'o <tytso@mit.edu>.

CC: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

- for(..) { mark_dquot_dirty(); } -> mark_all_dquot_dirty()
- for(..) { dput(); }             -> dqput_all()
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

This patch also fixes write vs chown race condition.
Acked-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently inode_reservation is managed by fs itself and this
reservation is transfered on dquot_transfer(). This means what
inode_reservation must always be in sync with
dquot->dq_dqb.dqb_rsvspace. Otherwise dquot_transfer() will result
in incorrect quota(WARN_ON in dquot_claim_reserved_space() will be
triggered)
This is not easy because of complex locking order issues
for example http://bugzilla.kernel.org/show_bug.cgi?id=14739

The patch introduce quota reservation field for each fs-inode
(fs specific inode is used in order to prevent bloating generic
vfs inode). This reservation is managed by quota code internally
similar to i_blocks/i_bytes and may not be always in sync with
internal fs reservation.

Also perform some code rearrangement:
- Unify dquot_reserve_space() and dquot_reserve_space()
- Unify dquot_release_reserved_space() and dquot_free_space()
- Also this patch add missing warning update to release_rsv()
  dquot_release_reserved_space() must call flush_warnings() as
  dquot_free_space() does.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Quota code requires unlocked version of this function. Off course
we can just copy-paste the code, but copy-pasting is always an evil.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently all quota block reservation macros contains hardcoded "2"
aka MAXQUOTAS value. This is no good because in some places it is not
obvious to understand what does this digit represent. Let's introduce
new macro with self descriptive name.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

loff_t is a type that isn't entirely dependant upon 32 v 64bit choice
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* pull ACC_MODE to fs.h; we have several copies all over the place
* nightmarish expression calculating f_mode by f_flags deserves a helper
too (OPEN_FMODE(flags))
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Just set f_flags when shoving struct file into nameidata; don't
postpone that until __dentry_open().  do_filp_open() has correct
value; lookup_instantiate_filp() doesn't - we lose the difference
between O_RDWR and 3 by that point.

We still set .intent.open.flags, so no fs code needs to be changed.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

It seems a couple places such as arch/ia64/kernel/perfmon.c and
drivers/infiniband/core/uverbs_main.c could use anon_inode_getfile()
instead of a private pseudo-fs + alloc_file(), if only there were a way
to get a read-only file.  So provide this by having anon_inode_getfile()
create a read-only file if we pass O_RDONLY in flags.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

No driver uses SG_SET_TRANSFORM any more in Linux, since the ide-scsi
driver was removed in 2.6.29. The compat-ioctl cleanup series moved
the handling for this around, which broke building without CONFIG_BLOCK.

Just remove the code handling it for compat mode.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

When alloc_file() and init_file() were combined, the error handling of
mnt_clone_write() was taken into alloc_file() in a somewhat obfuscated
way.  Since we don't use the error code for anything except warning,
we might as well warn directly without an extra variable.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>