This reverts commit 1f6d6482.

This commit resulted in regressions in performance in low
memory situations where kswapd was doing writeback of delayed
allocation blocks. It resulted in significant parallelism of the
kswapd work and with the special kswapd flags meant that hundreds of
active allocation could dip into kswapd specific memory reserves and
avoid being throttled. This cause a large amount of performance
variation, as well as random OOM-killer invocations that didn't
previously exist.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

iter_file_splice_write() - a ->splice_write() instance that gathers the
pipe buffers, builds a bio_vec-based iov_iter covering those and feeds
it to ->write_iter().  A bunch of simple cases coverted to that...

[AV: fixed the braino spotted by Cyrill]
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The kernel has no concept of capabilities with respect to inodes; inodes
exist independently of namespaces.  For example, inode_capable(inode,
CAP_LINUX_IMMUTABLE) would be nonsense.

This patch changes inode_capable to check for uid and gid mappings and
renames it to capable_wrt_inode_uidgid, which should make it more
obvious what it does.

Fixes CVE-2014-4014.

Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kbuild test robot reported:

>> fs/xfs/xfs_dir2_readdir.c:672:41: sparse: Using plain integer as NULL pointer

Fix it.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Rounding in xfs_alloc_fix_len() is wrong. As the comment states, the
result should be a number of a form (k*prod+mod) however due to sign
mistake the result is different. As a result allocations on raid arrays
could be misaligned in some cases.

This also seems to fix occasional assertion failure:
	XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0)
in xfs_alloc_ag_vextent_size().

Also add an assertion that the result of xfs_alloc_fix_len() is of
expected form.
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

I recently ran into the issue fixed by

  "xfs: kill buffers over failed write ranges properly"

which spams the log with lots of backtraces.  Make debugging any
issues like that easier by using WARN_ON_ONCE in the writeback code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

There are two checkpatch.pl complaints here because of the bad
indenting and because of the assignment inside the condition.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Most of the callers are just calling ASSERT(!xfs_buf_geterror())
which means they are checking for bp->b_error == 0. If bp is null in
this case, we will assert fail, and hence it's no different in
result to oopsing because of a null bp. In some cases, errors have
already been checked for or the function returning the buffer can't
return a buffer with an error, so it's just a redundant assert.
Either way, the assert can either be removed.

The other two non-assert callers can just test for a buffer and
error properly.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Commit daba5427 ("xfs: skip verification on initial "guess"
superblock read") dropped the use of a verifier for the initial
superblock read so we can probe the sector size of the filesystem
stored in the superblock. It, however, now fails to validate that
what was read initially is actually an XFS superblock and hence will
fail the sector size check and return ENOSYS.

This causes probe-based mounts to fail because it expects XFS to
return EINVAL when it doesn't recognise the superblock format.

cc: <stable@vger.kernel.org>
Reported-by: NPlamen Petrov <plamen.sisi@gmail.com>
Tested-by: NPlamen Petrov <plamen.sisi@gmail.com>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Upon memory pressure, kswapd calls xfs_vm_writepage() from
shrink_page_list(). This can result in delayed allocation occurring
and that gets deferred to the the allocation workqueue.

The allocation then runs outside kswapd context, which means if it
needs memory (and it does to demand page metadata from disk) it can
block in shrink_inactive_list() waiting for IO congestion. These
blocking waits are normally avoiding in kswapd context, so under
memory pressure writeback from kswapd can be arbitrarily delayed by
memory reclaim.

To avoid this, pass the kswapd context to the allocation being done
by the workqueue, so that memory reclaim understands correctly that
the work is being done for kswapd and therefore it is not blocked
and does not delay memory reclaim.

To avoid issues with int->char conversion of flag fields (as noticed
in v1 of this patch) convert the flag fields in the struct
xfs_bmalloca to bool types. pahole indicates these variables are
still single byte variables, so no extra space is consumed by this
change.

cc: <stable@vger.kernel.org>
Reported-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

It's carried in state->args->geo, so there's no need to duplicate it
and use more stack space than necessary.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

As it's only ever called from contexts where the xfs_da_args is
present and contains all the information needed inside the args
structure.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Rather than using the superblock value obtained through the
xfs_mount.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

We don't pass the xfs_da_args or the geometry all the way down to
the directory buffer logging code, hence we have to use
mp->m_dir_geo here. Fix this to use the geometry passed via the
xfs_da_args, and convert all the directory logging functions for
consistency.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

There are many places in the directory code were we don't pass the
args into and so have to extract the geometry direct from the mount
structure. Push the args or the geometry into these leaf functions
so that we don't need to grab it from the struct xfs_mount.

This, in turn, brings use to the point where directory geometry is
no longer a property of the struct xfs_mount; it is not a global
property anymore, and hence we can start to consider per-directory
configuration of physical geometries.

Start by converting the xfs_dir_isblock/leaf code - pass in the
xfs_da_args and convert the readdir code to use xfs_da_args like
the rest of the directory code to pass information around.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

They are just simple wrappers around xfs_dir2_byte_to_db(), and
we've already removed one usage earlier in the patch set. Kill
the rest before we start removing the xfs_mount from conversion
functions.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Because they aren't actually part of the on-disk format, and so
shouldn't be in xfs_da_format.h.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

The directory code has a dependency on the struct xfs_mount to
supply the directory block geometry. Block size, block log size,
and other parameters are pre-caclulated in the struct xfs_mount or
access directly from the superblock embedded in the struct
xfs_mount.

Extract all of this geometry information out of the struct xfs_mount
and superblock and place it into a new struct xfs_da_geometry
defined by the directory code. Allocate and initialise it at mount
time, and attach it to the struct xfs_mount so it canbe passed back
into the directory code appropriately rather than using the struct
xfs_mount.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfs_ialloc.h:102: error: expected ',' or '...' before 'delete'

Simple parameter rename, no changes to behaviour.
Signed-off-by: NRoger Willcocks <roger@filmlight.ltd.uk>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Write to a file with an offset greater than 16TB on 32-bit system and
then trigger page write-back via sync(1) will cause task hang.

# block_size=4096
# offset=$(((2**32 - 1) * $block_size))
# xfs_io -f -c "pwrite $offset $block_size" /storage/test_file
# sync

INFO: task sync:2590 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
sync            D c1064a28     0  2590   2097 0x00000000
.....
Call Trace:
[<c1064a28>] ? ttwu_do_wakeup+0x18/0x130
[<c1066d0e>] ? try_to_wake_up+0x1ce/0x220
[<c1066dbf>] ? wake_up_process+0x1f/0x40
[<c104fc2e>] ? wake_up_worker+0x1e/0x30
[<c15b6083>] schedule+0x23/0x60
[<c15b3c2d>] schedule_timeout+0x18d/0x1f0
[<c12a143e>] ? do_raw_spin_unlock+0x4e/0x90
[<c10515f1>] ? __queue_delayed_work+0x91/0x150
[<c12a12ef>] ? do_raw_spin_lock+0x3f/0x100
[<c12a143e>] ? do_raw_spin_unlock+0x4e/0x90
[<c15b5b5d>] wait_for_completion+0x7d/0xc0
[<c1066d60>] ? try_to_wake_up+0x220/0x220
[<c116a4d2>] sync_inodes_sb+0x92/0x180
[<c116fb05>] sync_inodes_one_sb+0x15/0x20
[<c114a8f8>] iterate_supers+0xb8/0xc0
[<c116faf0>] ? fdatawrite_one_bdev+0x20/0x20
[<c116fc21>] sys_sync+0x31/0x80
[<c15be18d>] sysenter_do_call+0x12/0x28

This issue can be triggered via xfstests/generic/308.

The reason is that the end_index is unsigned long with maximum value
'2^32-1=4294967295' on 32-bit platform, and the given offset cause it
wrapped to 0, so that the following codes will repeat again and again
until the task schedule time out:

end_index = offset >> PAGE_CACHE_SHIFT;
last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
if (page->index >= end_index) {
	unsigned offset_into_page = offset & (PAGE_CACHE_SIZE - 1);
        /*
         * Just skip the page if it is fully outside i_size, e.g. due
         * to a truncate operation that is in progress.
         */
        if (page->index >= end_index + 1 || offset_into_page == 0) {
	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
		unlock_page(page);
		return 0;
	}

In order to check if a page is fully outsids i_size or not, we can fix
the code logic as below:
	if (page->index > end_index ||
	    (page->index == end_index && offset_into_page == 0))

Secondly, there still has another similar issue when calculating the
end offset for mapping the filesystem blocks to the file blocks for
delalloc.  With the same tests to above, run unmount(8) will cause
kernel panic if CONFIG_XFS_DEBUG is enabled:

XFS: Assertion failed: XFS_FORCED_SHUTDOWN(ip->i_mount) || \
	ip->i_delayed_blks == 0, file: fs/xfs/xfs_super.c, line: 964

kernel BUG at fs/xfs/xfs_message.c:108!
invalid opcode: 0000 [#1] SMP
task: edddc100 ti: ec6ee000 task.ti: ec6ee000
EIP: 0060:[<f83d87cb>] EFLAGS: 00010296 CPU: 1
EIP is at assfail+0x2b/0x30 [xfs]
..............
Call Trace:
[<f83d9cd4>] xfs_fs_destroy_inode+0x74/0x120 [xfs]
[<c115ddf1>] destroy_inode+0x31/0x50
[<c115deff>] evict+0xef/0x170
[<c115dfb2>] dispose_list+0x32/0x40
[<c115ea3a>] evict_inodes+0xca/0xe0
[<c1149706>] generic_shutdown_super+0x46/0xd0
[<c11497b9>] kill_block_super+0x29/0x70
[<c1149a14>] deactivate_locked_super+0x44/0x70
[<c114a427>] deactivate_super+0x47/0x60
[<c1161c3d>] mntput_no_expire+0xcd/0x120
[<c1162ae8>] SyS_umount+0xa8/0x370
[<c1162dce>] SyS_oldumount+0x1e/0x20
[<c15be18d>] sysenter_do_call+0x12/0x28

That because the end_offset is evaluated to 0 which is the same reason
to above, hence the mapping and covertion for dealloc file blocks to
file system blocks did not happened.

This patch just fixed both issues.
Reported-by: NMichael L. Semon <mlsemon35@gmail.com>
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

All of the verification checks of magic numbers are now done by
verifiers, so ther eis no need to check them again once the buffer
has been successfully read. If the magic number is bad, it won't
even get to that code to verify it so it really serves no purpose at
all anymore. Remove it.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

The addition of direct formatting of log items into the CIL
linear buffer added alignment restrictions that the start of each
vector needed to be 64 bit aligned. Hence padding was added in
xlog_finish_iovec() to round up the vector length to ensure the next
vector started with the correct alignment.

This adds a small number of bytes to the size of
the linear buffer that is otherwise unused. The issue is that we
then use the linear buffer size to determine the log space used by
the log item, and this includes the unused space. Hence when we
account for space used by the log item, it's more than is actually
written into the iclogs, and hence we slowly leak this space.

This results on log hangs when reserving space, with threads getting
stuck with these stack traces:

Call Trace:
[<ffffffff81d15989>] schedule+0x29/0x70
[<ffffffff8150d3a2>] xlog_grant_head_wait+0xa2/0x1a0
[<ffffffff8150d55d>] xlog_grant_head_check+0xbd/0x140
[<ffffffff8150ee33>] xfs_log_reserve+0x103/0x220
[<ffffffff814b7f05>] xfs_trans_reserve+0x2f5/0x310
.....

The 4 bytes is significant. Brain Foster did all the hard work in
tracking down a reproducable leak to inode chunk allocation (it went
away with the ikeep mount option). His rough numbers were that
creating 50,000 inodes leaked 11 log blocks. This turns out to be
roughly 800 inode chunks or 1600 inode cluster buffers. That
works out at roughly 4 bytes per cluster buffer logged, and at that
I started looking for a 4 byte leak in the buffer logging code.

What I found was that a struct xfs_buf_log_format structure for an
inode cluster buffer is 28 bytes in length. This gets rounded up to
32 bytes, but the vector length remains 28 bytes. Hence the CIL
ticket reservation is decremented by 32 bytes (via lv->lv_buf_len)
for that vector rather than 28 bytes which are written into the log.

The fix for this problem is to separately track the bytes used by
the log vectors in the item and use that instead of the buffer
length when accounting for the log space that will be used by the
formatted log item.

Again, thanks to Brian Foster for doing all the hard work and long
hours to isolate this leak and make finding the bug relatively
simple.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

There is no need to dip into reserve pool. Reserve pool is used for much
more important things. And xfs_trans_reserve will never return ENOSPC
because punch hole is already done. If we get ENOSPC, collapse range
will be simply failed.

Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAshish Sangwan <a.sangwan@samsung.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

We reject any filesystem that is mounted with this feature bit set,
so we don't need to check for it anywhere else. Remove the function
for checking if the feature bit is set and any code that uses it.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

If the the V2 directory feature bit is not set in the superblock
feature mask the filesystem will fail the good version check.
Hence we don't need any other version checking on the dir2 feature
bit in the code as the filesystem will not mount without it set.
Remove the checking code.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

mkfs has turned on the XFS_SB_VERSION_NLINKBIT feature bit by
default since November 2007. It's about time we simply made the
kernel code turn it on by default and so always convert v1 inodes to
v2 inodes when reading them in from disk or allocating them. This
This removes needless version checks and modification when bumping
link counts on inodes, and will take code out of a few common code
paths.

   text    data     bss     dec     hex filename
 783251  100867     616  884734   d7ffe fs/xfs/xfs.o.orig
 782664  100867     616  884147   d7db3 fs/xfs/xfs.o.patched
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Whenever we update sb_features2, we need to update sb_bad_features2
so that they remain identical on disk. This prevents future mounts
or userspace utilities from getting confused over which features the
filesystem supports.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

We only support filesystems that have v2 directory support, and than
means all the checking and handling of superblock versions prior to
this support being added is completely unnecessary overhead.

Strip out all the version 1-3 support, sanitise the good version
checking to reflect the supported versions, update all the feature
supported functions and clean up all the support bit definitions to
reflect the fact that we no longer care about Irix bootloader flag
regions for v4 feature bits. Also, convert the return values to
boolean types and remove typedefs from function declarations to
clean up calling conventions, too.

Because the feature bit checking is all inline code, this relatively
small cleanup has a noticable impact on code size:

   text    data     bss     dec     hex filename
 785195  100867     616  886678   d8796 fs/xfs/xfs.o.orig
 783595  100867     616  885078   d8156 fs/xfs/xfs.o.patched

i.e. it reduces it by 1600 bytes.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

And we don't invert it properly when initialising the dquot lru
list.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>