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26867 commits

Author SHA1 Message Date
Christoph Hellwig
4c46819a80 xfs: do not write the buffer from xfs_iflush
Instead of writing the buffer directly from inside xfs_iflush return it to
the caller and let the caller decide what to do with the buffer.  Also
remove the pincount check in xfs_iflush that all non-blocking callers already
implement and the now unused flags parameter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:28 -05:00
Christoph Hellwig
8a48088f64 xfs: don't flush inodes from background inode reclaim
We already flush dirty inodes throug the AIL regularly, there is no reason
to have second thread compete with it and disturb the I/O pattern.  We still
do write inodes when doing a synchronous reclaim from the shrinker or during
unmount for now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:28 -05:00
Christoph Hellwig
211e4d434b xfs: implement freezing by emptying the AIL
Now that we write back all metadata either synchronously or through
the AIL we can simply implement metadata freezing in terms of
emptying the AIL.

The implementation for this is fairly simply and straight-forward:
A new routine is added that asks the xfsaild to push the AIL to the
end and waits for it to complete and send a wakeup. The routine will
then loop if the AIL is not actually empty, and continue to do so
until the AIL is compeltely empty.

We keep an inode reclaim pass in the freeze process to avoid having
memory pressure have to reclaim inodes that require dirtying the
filesystem to be reclaimed after the freeze has completed. This
means we can also treat unmount in the exact same way as freeze.

As an upside we can now remove the radix tree based inode writeback
and xfs_unmountfs_writesb.

[ Dave Chinner:
	- Cleaned up commit message.
	- Added inode reclaim passes back into freeze.
	- Cleaned up wakeup mechanism to avoid the use of a new
	  sleep counter variable. ]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:27 -05:00
Christoph Hellwig
1c30462542 xfs: allow assigning the tail lsn with the AIL lock held
Provide a variant of xlog_assign_tail_lsn that has the AIL lock already
held.  By doing so we do an additional atomic_read + atomic_set under
the lock, which comes down to two instructions.

Switch xfs_trans_ail_update_bulk and xfs_trans_ail_delete_bulk to the
new version to reduce the number of lock roundtrips, and prepare for
a new addition that would require a third lock roundtrip in
xfs_trans_ail_delete_bulk.  This addition is also the reason for
slightly rearranging the conditionals and relying on xfs_log_space_wake
for checking that the filesystem has been shut down internally.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:26 -05:00
Christoph Hellwig
32ce90a4b7 xfs: remove log item from AIL in xfs_iflush after a shutdown
If a filesystem has been forced shutdown we are never going to write inodes
to disk, which means the inode items will stay in the AIL until we free
the inode. Currently that is not a problem, but a pending change requires us
to empty the AIL before shutting down the filesystem. In that case leaving
the inode in the AIL is lethal. Make sure to remove the log item from the AIL
to allow emptying the AIL on shutdown filesystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:25 -05:00
Christoph Hellwig
dea9609527 xfs: remove log item from AIL in xfs_qm_dqflush after a shutdown
If a filesystem has been forced shutdown we are never going to write dquots
to disk, which means the dquot items will stay in the AIL forever.
Currently that is not a problem, but a pending chance requires us to
empty the AIL before shutting down the filesystem, in which case this
behaviour is lethal.  Make sure to remove the log item from the AIL
to allow emptying the AIL on shutdown filesystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:24 -05:00
Shaohua Li
7582df516c xfs: using GFP_NOFS for blkdev_issue_flush
Issuing a block device flush request in transaction context using GFP_KERNEL
directly can cause deadlocks due to memory reclaim recursion. Use GFP_NOFS to
avoid recursion from reclaim context.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:23 -05:00
Dave Chinner
01c84d2dc1 xfs: punch all delalloc blocks beyond EOF on write failure.
I've been seeing regular ASSERT failures in xfstests when running
fsstress based tests over the past month. xfs_getbmap() has been
failing this test:

XFS: Assertion failed: ((iflags & BMV_IF_DELALLOC) != 0) ||
(map[i].br_startblock != DELAYSTARTBLOCK), file: fs/xfs/xfs_bmap.c,
line: 5650

where it is encountering a delayed allocation extent after writing
all the dirty data to disk and then walking the extent map
atomically by holding the XFS_IOLOCK_SHARED to prevent new delayed
allocation extents from being created.

Test 083 on a 512 byte block size filesystem was used to reproduce
the problem, because it only had a 5s run timeand would usually fail
every 3-4 runs. This test is exercising ENOSPC behaviour by running
fsstress on a nearly full filesystem. The following trace extract
shows the final few events on the inode that tripped the assert:

 xfs_ilock:             flags ILOCK_EXCL caller xfs_setfilesize
 xfs_setfilesize:       isize 0x180000 disize 0x12d400 offset 0x17e200 count 7680

file size updated to 0x180000 by IO completion

 xfs_ilock:             flags ILOCK_EXCL caller xfs_iomap_write_delay
 xfs_iext_insert:       state  idx 3 offset 3072 block 4503599627239432 count 1 flag 0 caller xfs_bmap_add_extent_hole_delay
 xfs_get_blocks_alloc:  size 0x180000 offset 0x180000 count 512 type  startoff 0xc00 startblock -1 blockcount 0x1
 xfs_ilock:             flags ILOCK_EXCL caller __xfs_get_blocks

delalloc write, adding a single block at offset 0x180000

 xfs_delalloc_enospc:   isize 0x180000 disize 0x180000 offset 0x180200 count 512

ENOSPC trying to allocate a dellalloc block at offset 0x180200

 xfs_ilock:             flags ILOCK_EXCL caller xfs_iomap_write_delay
 xfs_get_blocks_alloc:  size 0x180000 offset 0x180200 count 512 type  startoff 0xc00 startblock -1 blockcount 0x2

And succeeding on retry after flushing dirty inodes.

 xfs_ilock:             flags ILOCK_EXCL caller __xfs_get_blocks
 xfs_delalloc_enospc:   isize 0x180000 disize 0x180000 offset 0x180400 count 512

ENOSPC trying to allocate a dellalloc block at offset 0x180400

 xfs_ilock:             flags ILOCK_EXCL caller xfs_iomap_write_delay
 xfs_delalloc_enospc:   isize 0x180000 disize 0x180000 offset 0x180400 count 512

And failing the retry, giving a real ENOSPC error.

 xfs_ilock:             flags ILOCK_EXCL caller xfs_vm_write_failed
                                                ^^^^^^^^^^^^^^^^^^^
The smoking gun - the write being failed and cleaning up delalloc
blocks beyond EOF allocated by the failed write.

 xfs_getattr:
 xfs_ilock:             flags IOLOCK_SHARED caller xfs_getbmap
 xfs_ilock:             flags ILOCK_SHARED caller xfs_ilock_map_shared

And that's where we died almost immediately afterwards.
xfs_bmapi_read() found delalloc extent beyond current file in memory
file size. Some debug I added to xfs_getbmap() showed the state just
before the assert failure:

 ino 0x80e48: off 0xc00, fsb 0xffffffffffffffff, len 0x1, size 0x180000
 start_fsb 0x106, end_fsb 0x638
 ino flags 0x2 nex 0xd bmvcnt 0x555, len 0x3c58a6f23c0bf1, start 0xc00
 ext 0: off 0x1fc, fsb 0x24782, len 0x254
 ext 1: off 0x450, fsb 0x40851, len 0x30
 ext 2: off 0x480, fsb 0xd99, len 0x1b8
 ext 3: off 0x92f, fsb 0x4099a, len 0x3b
 ext 4: off 0x96d, fsb 0x41844, len 0x98
 ext 5: off 0xbf1, fsb 0x408ab, len 0xf

which shows that we found a single delalloc block beyond EOF (first
line of output) when we were returning the map for a length
somewhere around 10^16 bytes long (second line), and the on-disk
extents showed they didn't go past EOF (last lines).

Further debug added to xfs_vm_write_failed() showed this happened
when punching out delalloc blocks beyond the end of the file after
the failed write:

[  132.606693] ino 0x80e48: vwf to 0x181000, sze 0x180000
[  132.609573] start_fsb 0xc01, end_fsb 0xc08

It punched the range 0xc01 -> 0xc08, but the range we really need to
punch is 0xc00 -> 0xc07 (8 blocks from 0xc00) as this testing was
run on a 512 byte block size filesystem (8 blocks per page).
the punch from is 0xc00. So end_fsb is correct, but start_fsb is
wrong as we punch from start_fsb for (end_fsb - start_fsb) blocks.
Hence we are not punching the delalloc block beyond EOF in the case.

The fix is simple - it's a silly off-by-one mistake in calculating
the range. It's especially silly because the macro used to calculate
the start_fsb already takes into account the case where the inode
size is an exact multiple of the filesystem block size...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:22 -05:00
Dave Chinner
507630b29f xfs: use shared ilock mode for direct IO writes by default
For the direct IO write path, we only really need the ilock to be taken in
exclusive mode during IO submission if we need to do extent allocation
instead of all the time.

Change the block mapping code to take the ilock in shared mode for the
initial block mapping, and only retake it exclusively when we actually
have to perform extent allocations.  We were already dropping the ilock
for the transaction allocation, so this doesn't introduce new race windows.

Based on an earlier patch from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:21 -05:00
Christoph Hellwig
193aec1050 xfs: push the ilock into xfs_zero_eof
Instead of calling xfs_zero_eof with the ilock held only take it internally
for the minimall required critical section around xfs_bmapi_read.  This
also requires changing the calling convention for xfs_zero_last_block
slightly.  The actual zeroing operation is still serialized by the iolock,
which must be taken exclusively over the call to xfs_zero_eof.

We could in fact use a shared lock for the xfs_bmapi_read calls as long as
the extent list has been read in, but given that we already hold the iolock
exclusively there is little reason to micro optimize this further.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:20 -05:00
Christoph Hellwig
f38996f576 xfs: reduce ilock hold times in xfs_setattr_size
We do not need the ilock for most checks done in the beginning of
xfs_setattr_size.  Replace the long critical section before starting the
transaction with a smaller one around xfs_zero_eof and an optional one
inside xfs_qm_dqattach that isn't entered unless using quotas.  While
this isn't a big optimization for xfs_setattr_size itself it will allow
pushing the ilock into xfs_zero_eof itself later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2012-05-14 16:20:18 -05:00
Christoph Hellwig
467f78992a xfs: reduce ilock hold times in xfs_file_aio_write_checks
We do not need the ilock for generic_write_checks and the i_size_read,
which are protected by i_mutex and/or iolock, so reduce the ilock
critical section to just the call to xfs_zero_eof.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:17 -05:00
Christoph Hellwig
b4d05e3019 xfs: avoid taking the ilock unnessecarily in xfs_qm_dqattach
Check if we actually need to attach a dquot before taking the ilock in
xfs_qm_dqattach.  This avoid superflous lock roundtrips for the common cases
of quota support compiled in but not activated on a filesystem and an
inode that already has the dquots attached.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:15 -05:00
Alan Stern
356c05d58a sysfs: get rid of some lockdep false positives
This patch (as1554) fixes a lockdep false-positive report.  The
problem arises because lockdep is unable to deal with the
tree-structured locks created by the device core and sysfs.

This particular problem involves a sysfs attribute method that
unregisters itself, not from the device it was called for, but from a
descendant device.  Lockdep doesn't understand the distinction and
reports a possible deadlock, even though the operation is safe.

This is the sort of thing that would normally be handled by using a
nested lock annotation; unfortunately it's not feasible to do that
here.  There's no sensible way to tell sysfs when attribute removal
occurs in the context of a parent attribute method.

As a workaround, the patch adds a new flag to struct attribute
telling sysfs not to inform lockdep when it acquires a readlock on a
sysfs_dirent instance for the attribute.  The readlock is still
acquired, but lockdep doesn't know about it and hence does not
complain about impossible deadlock scenarios.

Also added are macros for static initialization of attribute
structures with the ignore_lockdep flag set.  The three offending
attributes in the USB subsystem are converted to use the new macros.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Tejun Heo <tj@kernel.org>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14 12:19:56 -07:00
Linus Torvalds
9ff00d58a9 Three fixes for 3.4:
- Fix a lock ordering deadlock in JFFS2
  - Fix an oops in the dataflash driver, triggered by a dummy call to test
    whether it has OTP functionality.
  - Fix request_mem_region() failure on amsdelta NAND driver.
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Merge tag 'for-linus-3.4-20120513' of git://git.infradead.org/linux-mtd

Pull three MTD fixes from David Woodhouse:
 - Fix a lock ordering deadlock in JFFS2
 - Fix an oops in the dataflash driver, triggered by a dummy call to test
   whether it has OTP functionality.
 - Fix request_mem_region() failure on amsdelta NAND driver.

* tag 'for-linus-3.4-20120513' of git://git.infradead.org/linux-mtd:
  mtd: ams-delta: fix request_mem_region() failure
  jffs2: Fix lock acquisition order bug in gc path
  mtd: fix oops in dataflash driver
2012-05-13 11:33:09 -07:00
Rafael J. Wysocki
351520a9eb Merge branch 'pm-sleep'
* pm-sleep:
  PM / Sleep: User space wakeup sources garbage collector Kconfig option
  PM / Sleep: Make the limit of user space wakeup sources configurable
  PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
  PM / Sleep: Fix a mistake in a conditional in autosleep_store()
  epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
  PM / Sleep: Add user space interface for manipulating wakeup sources, v3
  PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
  PM / Sleep: Implement opportunistic sleep, v2
  PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
  PM / Sleep: Change wakeup source statistics to follow Android
  PM / Sleep: Use wait queue to signal "no wakeup events in progress"
  PM / Sleep: Look for wakeup events in later stages of device suspend
  PM / Hibernate: Hibernate/thaw fixes/improvements
2012-05-11 21:15:09 +02:00
Bernd Schubert
f908ee9463 bio allocation failure due to bio_get_nr_vecs()
The number of bio_get_nr_vecs() is passed down via bio_alloc() to
bvec_alloc_bs(), which fails the bio allocation if
nr_iovecs > BIO_MAX_PAGES. For the underlying caller this causes an
unexpected bio allocation failure.
Limiting to queue_max_segments() is not sufficient, as max_segments
also might be very large.

bvec_alloc_bs(gfp_mask, nr_iovecs, ) => NULL when nr_iovecs  > BIO_MAX_PAGES
bio_alloc_bioset(gfp_mask, nr_iovecs, ...)
bio_alloc(GFP_NOIO, nvecs)
xfs_alloc_ioend_bio()

Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-11 16:45:12 +02:00
Jeff Moyer
080399aaaf block: don't mark buffers beyond end of disk as mapped
Hi,

We have a bug report open where a squashfs image mounted on ppc64 would
exhibit errors due to trying to read beyond the end of the disk.  It can
easily be reproduced by doing the following:

[root@ibm-p750e-02-lp3 ~]# ls -l install.img
-rw-r--r-- 1 root root 142032896 Apr 30 16:46 install.img
[root@ibm-p750e-02-lp3 ~]# mount -o loop ./install.img /mnt/test
[root@ibm-p750e-02-lp3 ~]# dd if=/dev/loop0 of=/dev/null
dd: reading `/dev/loop0': Input/output error
277376+0 records in
277376+0 records out
142016512 bytes (142 MB) copied, 0.9465 s, 150 MB/s

In dmesg, you'll find the following:

squashfs: version 4.0 (2009/01/31) Phillip Lougher
[   43.106012] attempt to access beyond end of device
[   43.106029] loop0: rw=0, want=277410, limit=277408
[   43.106039] Buffer I/O error on device loop0, logical block 138704
[   43.106053] attempt to access beyond end of device
[   43.106057] loop0: rw=0, want=277412, limit=277408
[   43.106061] Buffer I/O error on device loop0, logical block 138705
[   43.106066] attempt to access beyond end of device
[   43.106070] loop0: rw=0, want=277414, limit=277408
[   43.106073] Buffer I/O error on device loop0, logical block 138706
[   43.106078] attempt to access beyond end of device
[   43.106081] loop0: rw=0, want=277416, limit=277408
[   43.106085] Buffer I/O error on device loop0, logical block 138707
[   43.106089] attempt to access beyond end of device
[   43.106093] loop0: rw=0, want=277418, limit=277408
[   43.106096] Buffer I/O error on device loop0, logical block 138708
[   43.106101] attempt to access beyond end of device
[   43.106104] loop0: rw=0, want=277420, limit=277408
[   43.106108] Buffer I/O error on device loop0, logical block 138709
[   43.106112] attempt to access beyond end of device
[   43.106116] loop0: rw=0, want=277422, limit=277408
[   43.106120] Buffer I/O error on device loop0, logical block 138710
[   43.106124] attempt to access beyond end of device
[   43.106128] loop0: rw=0, want=277424, limit=277408
[   43.106131] Buffer I/O error on device loop0, logical block 138711
[   43.106135] attempt to access beyond end of device
[   43.106139] loop0: rw=0, want=277426, limit=277408
[   43.106143] Buffer I/O error on device loop0, logical block 138712
[   43.106147] attempt to access beyond end of device
[   43.106151] loop0: rw=0, want=277428, limit=277408
[   43.106154] Buffer I/O error on device loop0, logical block 138713
[   43.106158] attempt to access beyond end of device
[   43.106162] loop0: rw=0, want=277430, limit=277408
[   43.106166] attempt to access beyond end of device
[   43.106169] loop0: rw=0, want=277432, limit=277408
...
[   43.106307] attempt to access beyond end of device
[   43.106311] loop0: rw=0, want=277470, limit=2774

Squashfs manages to read in the end block(s) of the disk during the
mount operation.  Then, when dd reads the block device, it leads to
block_read_full_page being called with buffers that are beyond end of
disk, but are marked as mapped.  Thus, it would end up submitting read
I/O against them, resulting in the errors mentioned above.  I fixed the
problem by modifying init_page_buffers to only set the buffer mapped if
it fell inside of i_size.

Cheers,
Jeff

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Nick Piggin <npiggin@kernel.dk>

--

Changes from v1->v2: re-used max_block, as suggested by Nick Piggin.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-11 16:42:14 +02:00
Bob Peterson
41db1ab9be GFS2: Add rgrp information to block_alloc trace point
This is a second attempt at a patch that adds rgrp information to the
block allocation trace point for GFS2. As suggested, the patch was
modified to list the rgrp information _after_ the fields that exist today.

Again, the reason for this patch is to allow us to trace and debug
problems with the block reservations patch, which is still in the works.
We can debug problems with reservations if we can see what block allocations
result from the block reservations. It may also be handy in figuring out
if there are problems in rgrp free space accounting. In other words,
we can use it to track the rgrp and its free space along side the allocations
that are taking place.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-05-11 10:31:34 +01:00
Bob Peterson
f2f9c81244 GFS2: Eliminate unused "new" parameter to gfs2_meta_indirect_buffer
It turns out that the "new" parameter to function gfs2_meta_indirect_buffer
was always being passed in as zero. Therefore, this patch eliminates it
and simplifies the function.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-05-11 10:19:23 +01:00
Linus Torvalds
26fe575028 vfs: make it possible to access the dentry hash/len as one 64-bit entry
This allows comparing hash and len in one operation on 64-bit
architectures.  Right now only __d_lookup_rcu() takes advantage of this,
since that is the case we care most about.

The use of anonymous struct/unions hides the alternate 64-bit approach
from most users, the exception being a few cases where we initialize a
'struct qstr' with a static initializer.  This makes the problematic
cases use a new QSTR_INIT() helper function for that (but initializing
just the name pointer with a "{ .name = xyzzy }" initializer remains
valid, as does just copying another qstr structure).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10 19:54:35 -07:00
Linus Torvalds
ee983e8967 vfs: move dentry name length comparison from dentry_cmp() into callers
All callers do want to check the dentry length, but some of them can
check the length and the hash together, so doing it in dentry_cmp() can
be counter-productive.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10 19:54:35 -07:00
Linus Torvalds
94753db5ed vfs: do the careful dentry name access for all dentry_cmp cases
Commit 12f8ad4b05 ("vfs: clean up __d_lookup_rcu() and dentry_cmp()
interfaces") did the careful ACCESS_ONCE() of the dentry name only for
the word-at-a-time case, even though the issue is generic.

Admittedly I don't really see gcc ever reloading the value in the middle
of the loop, so the ACCESS_ONCE() protects us from a fairly theoretical
issue. But better safe than sorry.

Also, this consolidates the common parts of the word-at-a-time and
bytewise logic, which includes checking the length.  We'll be changing
that later.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10 19:54:09 -07:00
Linus Torvalds
8c01a529b8 vfs: remove unnecessary d_unhashed() check from __d_lookup_rcu
The check for d_unhashed() is not strictly incorrect, but at the same
time it is also not sensible.  The actual dentry removal from the dentry
hash chains is totally asynchronous to the __d_lookup_rcu() logic, and
we depend on __d_drop() updating the sequence number to invalidate any
lookup of an unhashed dentry.

So checking d_unhashed() is not incorrect, but it's not useful either:
the code has to work correctly even without it. So just remove it.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10 19:52:35 -07:00
Linus Torvalds
7c283324da Merge branch 'akpm' (Andrew's patch-bomb)
Merge misc fixes from Andrew Morton.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (8 patches)
  MAINTAINERS: add maintainer for LED subsystem
  mm: nobootmem: fix sign extend problem in __free_pages_memory()
  drivers/leds: correct __devexit annotations
  memcg: free spare array to avoid memory leak
  namespaces, pid_ns: fix leakage on fork() failure
  hugetlb: prevent BUG_ON in hugetlb_fault() -> hugetlb_cow()
  mm: fix division by 0 in percpu_pagelist_fraction()
  proc/pid/pagemap: correctly report non-present ptes and holes between vmas
2012-05-10 15:17:24 -07:00
Konstantin Khlebnikov
16fbdce62d proc/pid/pagemap: correctly report non-present ptes and holes between vmas
Reset the current pagemap-entry if the current pte isn't present, or if
current vma is over.  Otherwise pagemap reports last entry again and
again.

Non-present pte reporting was broken in commit 092b50bacd ("pagemap:
introduce data structure for pagemap entry")

Reporting for holes was broken in commit 5aaabe831e ("pagemap: avoid
splitting thp when reading /proc/pid/pagemap")

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10 15:06:44 -07:00
Dan Carpenter
48a5730e5b cifs: fix revalidation test in cifs_llseek()
This test is always true so it means we revalidate the length every
time, which generates more network traffic.  When it is SEEK_SET or
SEEK_CUR, then we don't need to revalidate.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-05-09 15:16:22 -05:00
Bob Peterson
6de1e2f34a GFS2: Remove redundant metadata block type check
This patch removes a redundant metadata block check. See description below.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-05-08 16:18:55 +01:00
David S. Miller
0d6c4a2e46 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/e1000e/param.c
	drivers/net/wireless/iwlwifi/iwl-agn-rx.c
	drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c
	drivers/net/wireless/iwlwifi/iwl-trans.h

Resolved the iwlwifi conflict with mainline using 3-way diff posted
by John Linville and Stephen Rothwell.  In 'net' we added a bug
fix to make iwlwifi report a more accurate skb->truesize but this
conflicted with RX path changes that happened meanwhile in net-next.

In e1000e a conflict arose in the validation code for settings of
adapter->itr.  'net-next' had more sophisticated logic so that
logic was used.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-07 23:35:40 -04:00
Josh Cartwright
226bb7df3d jffs2: Fix lock acquisition order bug in gc path
The locking policy is such that the erase_complete_block spinlock is
nested within the alloc_sem mutex.  This fixes a case in which the
acquisition order was erroneously reversed.  This issue was caught by
the following lockdep splat:

   =======================================================
   [ INFO: possible circular locking dependency detected ]
   3.0.5 #1
   -------------------------------------------------------
   jffs2_gcd_mtd6/299 is trying to acquire lock:
    (&c->alloc_sem){+.+.+.}, at: [<c01f7714>] jffs2_garbage_collect_pass+0x314/0x890

   but task is already holding lock:
    (&(&c->erase_completion_lock)->rlock){+.+...}, at: [<c01f7708>] jffs2_garbage_collect_pass+0x308/0x890

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #1 (&(&c->erase_completion_lock)->rlock){+.+...}:
          [<c008bec4>] validate_chain+0xe6c/0x10bc
          [<c008c660>] __lock_acquire+0x54c/0xba4
          [<c008d240>] lock_acquire+0xa4/0x114
          [<c046780c>] _raw_spin_lock+0x3c/0x4c
          [<c01f744c>] jffs2_garbage_collect_pass+0x4c/0x890
          [<c01f937c>] jffs2_garbage_collect_thread+0x1b4/0x1cc
          [<c0071a68>] kthread+0x98/0xa0
          [<c000f264>] kernel_thread_exit+0x0/0x8

   -> #0 (&c->alloc_sem){+.+.+.}:
          [<c008ad2c>] print_circular_bug+0x70/0x2c4
          [<c008c08c>] validate_chain+0x1034/0x10bc
          [<c008c660>] __lock_acquire+0x54c/0xba4
          [<c008d240>] lock_acquire+0xa4/0x114
          [<c0466628>] mutex_lock_nested+0x74/0x33c
          [<c01f7714>] jffs2_garbage_collect_pass+0x314/0x890
          [<c01f937c>] jffs2_garbage_collect_thread+0x1b4/0x1cc
          [<c0071a68>] kthread+0x98/0xa0
          [<c000f264>] kernel_thread_exit+0x0/0x8

   other info that might help us debug this:

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(&(&c->erase_completion_lock)->rlock);
                                  lock(&c->alloc_sem);
                                  lock(&(&c->erase_completion_lock)->rlock);
     lock(&c->alloc_sem);

    *** DEADLOCK ***

   1 lock held by jffs2_gcd_mtd6/299:
    #0:  (&(&c->erase_completion_lock)->rlock){+.+...}, at: [<c01f7708>] jffs2_garbage_collect_pass+0x308/0x890

   stack backtrace:
   [<c00155dc>] (unwind_backtrace+0x0/0x100) from [<c0463dc0>] (dump_stack+0x20/0x24)
   [<c0463dc0>] (dump_stack+0x20/0x24) from [<c008ae84>] (print_circular_bug+0x1c8/0x2c4)
   [<c008ae84>] (print_circular_bug+0x1c8/0x2c4) from [<c008c08c>] (validate_chain+0x1034/0x10bc)
   [<c008c08c>] (validate_chain+0x1034/0x10bc) from [<c008c660>] (__lock_acquire+0x54c/0xba4)
   [<c008c660>] (__lock_acquire+0x54c/0xba4) from [<c008d240>] (lock_acquire+0xa4/0x114)
   [<c008d240>] (lock_acquire+0xa4/0x114) from [<c0466628>] (mutex_lock_nested+0x74/0x33c)
   [<c0466628>] (mutex_lock_nested+0x74/0x33c) from [<c01f7714>] (jffs2_garbage_collect_pass+0x314/0x890)
   [<c01f7714>] (jffs2_garbage_collect_pass+0x314/0x890) from [<c01f937c>] (jffs2_garbage_collect_thread+0x1b4/0x1cc)
   [<c01f937c>] (jffs2_garbage_collect_thread+0x1b4/0x1cc) from [<c0071a68>] (kthread+0x98/0xa0)
   [<c0071a68>] (kthread+0x98/0xa0) from [<c000f264>] (kernel_thread_exit+0x0/0x8)

This was introduce in '81cfc9f jffs2: Fix serious write stall due to erase'.

Cc: stable@kernel.org [2.6.37+]
Signed-off-by: Josh Cartwright <joshc@linux.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-05-07 20:30:14 +01:00
Linus Torvalds
8529f613b6 vfs: don't force a big memset of stat data just to clear padding fields
Admittedly this is something that the compiler should be able to just do
for us, but gcc just isn't that smart.  And trying to use a structure
initializer (which would get us the right semantics) ends up resulting
in gcc allocating stack space for _two_ 'struct stat', and then copying
one into the other.

So do it by hand - just have a per-architecture macro that initializes
the padding fields.  And if the architecture doesn't provide one, fall
back to the old behavior of just doing the whole memset() first.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-06 18:02:40 -07:00
Linus Torvalds
a52dd971f9 vfs: de-crapify "cp_new_stat()" function
It's an unreadable mess of 32-bit vs 64-bit #ifdef's that mostly follow
a rather simple pattern.

Make a helper #define to handle that pattern, in the process making the
code both shorter and more readable.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-06 17:47:30 -07:00
Linus Torvalds
271fd5d728 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "The big ones here are a memory leak we introduced in rc1, and a
  scheduling while atomic if the transid on disk doesn't match the
  transid we expected.  This happens for corrupt blocks, or out of date
  disks.

  It also fixes up the ioctl definition for our ioctl to resolve logical
  inode numbers.  The __u32 was a merging error and doesn't match what
  we ship in the progs."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: avoid sleeping in verify_parent_transid while atomic
  Btrfs: fix crash in scrub repair code when device is missing
  btrfs: Fix mismatching struct members in ioctl.h
  Btrfs: fix page leak when allocing extent buffers
  Btrfs: Add properly locking around add_root_to_dirty_list
2012-05-06 10:20:07 -07:00
Chris Mason
b9fab919b7 Btrfs: avoid sleeping in verify_parent_transid while atomic
verify_parent_transid needs to lock the extent range to make
sure no IO is underway, and so it can safely clear the
uptodate bits if our checks fail.

But, a few callers are using it with spinlocks held.  Most
of the time, the generation numbers are going to match, and
we don't want to switch to a blocking lock just for the error
case.  This adds an atomic flag to verify_parent_transid,
and changes it to return EAGAIN if it needs to block to
properly verifiy things.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-06 07:23:47 -04:00
Arve Hjønnevåg
4d7e30d989 epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
When an epoll_event, that has the EPOLLWAKEUP flag set, is ready, a
wakeup_source will be active to prevent suspend. This can be used to
handle wakeup events from a driver that support poll, e.g. input, if
that driver wakes up the waitqueue passed to epoll before allowing
suspend.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-05 21:50:41 +02:00
Linus Torvalds
12f8ad4b05 vfs: clean up __d_lookup_rcu() and dentry_cmp() interfaces
The calling conventions for __d_lookup_rcu() and dentry_cmp() are
annoying in different ways, and there is actually one single underlying
reason for both of the annoyances.

The fundamental reason is that we do the returned dentry sequence number
check inside __d_lookup_rcu() instead of doing it in the caller.  This
results in two annoyances:

 - __d_lookup_rcu() now not only needs to return the dentry and the
   sequence number that goes along with the lookup, it also needs to
   return the inode pointer that was validated by that sequence number
   check.

 - and because we did the sequence number check early (to validate the
   name pointer and length) we also couldn't just pass the dentry itself
   to dentry_cmp(), we had to pass the counted string that contained the
   name.

So that sequence number decision caused two separate ugly calling
conventions.

Both of these problems would be solved if we just did the sequence
number check in the caller instead.  There's only one caller, and that
caller already has to do the sequence number check for the parent
anyway, so just do that.

That allows us to stop returning the dentry->d_inode in that in-out
argument (pointer-to-pointer-to-inode), so we can make the inode
argument just a regular input inode pointer.  The caller can just load
the inode from dentry->d_inode, and then do the sequence number check
after that to make sure that it's synchronized with the name we looked
up.

And it allows us to just pass in the dentry to dentry_cmp(), which is
what all the callers really wanted.  Sure, dentry_cmp() has to be a bit
careful about the dentry (which is not stable during RCU lookup), but
that's actually very simple.

And now that dentry_cmp() can clearly see that the first string argument
is a dentry, we can use the direct word access for that, instead of the
careful unaligned zero-padding.  The dentry name is always properly
aligned, since it is a single path component that is either embedded
into the dentry itself, or was allocated with kmalloc() (see __d_alloc).

Finally, this also uninlines the nasty slow-case for dentry comparisons:
that one *does* need to do a sequence number check, since it will call
in to the low-level filesystems, and we want to give those a stable
inode pointer and path component length/start arguments.  Doing an extra
sequence check for that slow case is not a problem, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-04 18:21:14 -07:00
Greg Kroah-Hartman
6f24f89287 hfsplus: Fix potential buffer overflows
Commit ec81aecb29 ("hfs: fix a potential buffer overflow") fixed a few
potential buffer overflows in the hfs filesystem.  But as Timo Warns
pointed out, these changes also need to be made on the hfsplus
filesystem as well.

Reported-by: Timo Warns <warns@pre-sense.de>
Acked-by: WANG Cong <amwang@redhat.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Sage Weil <sage@newdream.net>
Cc: Eugene Teo <eteo@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: stable <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-04 17:11:24 -07:00
Linus Torvalds
c6de1687f5 Merge git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fixes from Steve French.

* git://git.samba.org/sfrench/cifs-2.6:
  fs/cifs: fix parsing of dfs referrals
  cifs: make sure we ignore the credentials= and cred= options
  [CIFS] Update cifs version to 1.78
  cifs - check S_AUTOMOUNT in revalidate
  cifs: add missing initialization of server->req_lock
  cifs: don't cap ra_pages at the same level as default_backing_dev_info
  CIFS: Fix indentation in cifs_show_options
2012-05-04 15:34:21 -07:00
Stefan Behrens
ea9947b439 Btrfs: fix crash in scrub repair code when device is missing
Fix that when scrub tries to repair an I/O or checksum error and one of
the devices containing the mirror is missing, it crashes in bio_add_page
because the bdev is a NULL pointer for missing devices.

Reported-by: Marco L. Crociani <marco.crociani@gmail.com>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:07 -04:00
Alexander Block
d04b1debc9 btrfs: Fix mismatching struct members in ioctl.h
Fix the size members of btrfs_ioctl_ino_path_args and
btrfs_ioctl_logical_ino_args. The user space btrfs-progs utilities used
__u64 and the kernel headers used __u32 before.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:06 -04:00
Josef Bacik
17de39ac17 Btrfs: fix page leak when allocing extent buffers
If we happen to alloc a extent buffer and then alloc a page and notice that
page is already attached to an extent buffer, we will only unlock it and
free our existing eb.  Any pages currently attached to that eb will be
properly freed, but we don't do the page_cache_release() on the page where
we noticed the other extent buffer which can cause us to leak pages and I
hope cause the weird issues we've been seeing in this area.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:06 -04:00
Chris Mason
e5846fc665 Btrfs: Add properly locking around add_root_to_dirty_list
add_root_to_dirty_list happens once at the very beginning of the
transaction, but it is still racey.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:14:11 -04:00
Steven Whitehouse
f9425ad4e5 GFS2: Fix sgid propagation when using ACLs
This cleans up the mode setting code when creating inodes. The
SGID bit was being reset by setattr_copy() when the user creating a
subdirectory was not in the owning group. When ACLs are in use this
SGID bit should have been propagated if the ACL allows creation of
a subdirectory. GFS2's behaviour now matches that of the other ACL
supporting filesystems in this regard.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-05-04 14:33:06 +01:00
Stefan Metzmacher
d8f2799b10 fs/cifs: fix parsing of dfs referrals
The problem was that the first referral was parsed more than once
and so the caller tried the same referrals multiple times.

The problem was introduced partly by commit
066ce68994,
where 'ref += le16_to_cpu(ref->Size);' got lost,
but that was also wrong...

Cc: <stable@vger.kernel.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Tested-by: Björn Jacke <bj@sernet.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-05-03 22:47:39 -05:00
James Morris
898bfc1d46 Linux 3.4-rc5
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Merge tag 'v3.4-rc5' into next

Linux 3.4-rc5

Merge to pull in prerequisite change for Smack:
86812bb0de

Requested by Casey.
2012-05-04 12:46:40 +10:00
Linus Torvalds
e419b4cc58 vfs: make word-at-a-time accesses handle a non-existing page
It turns out that there are more cases than CONFIG_DEBUG_PAGEALLOC that
can have holes in the kernel address space: it seems to happen easily
with Xen, and it looks like the AMD gart64 code will also punch holes
dynamically.

Actually hitting that case is still very unlikely, so just do the
access, and take an exception and fix it up for the very unlikely case
of it being a page-crosser with no next page.

And hey, this abstraction might even help other architectures that have
other issues with unaligned word accesses than the possible missing next
page.  IOW, this could do the byte order magic too.

Peter Anvin fixed a thinko in the shifting for the exception case.

Reported-and-tested-by: Jana Saout <jana@saout.de>
Cc:  Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-03 14:01:40 -07:00
Jeff Layton
a557b97616 cifs: make sure we ignore the credentials= and cred= options
Older mount.cifs programs passed this on to the kernel after parsing
the file. Make sure the kernel ignores that option.

Should fix:

    https://bugzilla.kernel.org/show_bug.cgi?id=43195

Cc: Sachin Prabhu <sprabhu@redhat.com>
Reported-by: Ronald <ronald645@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-05-03 13:50:01 -05:00
Steve French
f966424e99 [CIFS] Update cifs version to 1.78
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-05-03 13:50:01 -05:00
Ian Kent
936ad90944 cifs - check S_AUTOMOUNT in revalidate
When revalidating a dentry, if the inode wasn't known to be a dfs
entry when the dentry was instantiated, such as when created via
->readdir(), the DCACHE_NEED_AUTOMOUNT flag needs to be set on the
dentry in ->d_revalidate().

The false return from cifs_d_revalidate(), due to the inode now
being marked with the S_AUTOMOUNT flag, might not invalidate the
dentry if there is a concurrent unlazy path walk. This is because
the dentry reference count will be at least 2 in this case causing
d_invalidate() to return EBUSY. So the asumption that the dentry
will be discarded then correctly instantiated via ->lookup() might
not hold.

Signed-off-by: Ian Kent <raven@themaw.net>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: Steve French <smfrench@gmail.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-05-03 13:49:47 -05:00
Subodh Nijsure
1bdcc63112 UBIFS: remove xattr Kconnfig option
Remove CONFIG_UBIFS_FS_XATTR configuration option and associated
UBIFS_FS_XATTR ifdefs.

Testing:
       Tested using integck while using nandsim on x86 & MX28 based
       platform with Micron MT29F2G08ABAEAH4 nand.

Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-03 14:11:11 +03:00