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26690 commits

Author SHA1 Message Date
Dan Carpenter
72749a270b exofs: Cap on the memcpy() size
This data comes from the device, so probably it's fairly trustworthy but
it makes the static checkers happy if we check it.

[Boaz]
  the system_id_len is zero, if not present, or always OSD_SYSTEMID_LEN.
  So always copy OSD_SYSTEMID_LEN bytes.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2012-03-19 13:39:12 -07:00
Masanari Iida
3e57638bb1 exofs: (trivial) Fix typo in super.c
Correct spelling "faild" to "failed" in
fs/exofs/super.c

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2012-03-19 13:39:12 -07:00
Dan Carpenter
b6d1f2dd61 exofs: fix endian conversion in exofs_sync_fs()
fscb->s_numfiles is an __le64 field so we need to use cpu_to_le64()
to get a little endian 64 bit on big endian systems.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2012-03-19 13:39:11 -07:00
J. Bruce Fields
62b9510cb3 nfsd: merge cookie collision fixes from ext4 tree
These changes fix readdir loops on ext4 filesystems with dir_index
turned on.  I'm pulling them from Ted's tree as I'd like to give them
some extra nfsd testing, and expect to be applying (potentially
conflicting) patches to the same code before the next merge window.

From the nfs-ext4-premerge branch of

	git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-03-19 12:35:05 -04:00
Konrad Rzeszutek Wilk
16c0cfa425 Merge branch 'stable/cleancache.v13' into linux-next
* stable/cleancache.v13:
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/
2012-03-19 12:12:19 -04:00
Pavel Shilovsky
ce85852b90 CIFS: Fix a spurious error in cifs_push_posix_locks
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Steve French <stevef@smf-gateway.(none)>
2012-03-19 10:20:22 -05:00
David S. Miller
4da0bd7365 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-03-18 23:29:41 -04:00
Bernd Schubert
06effdbb49 nfsd: vfs_llseek() with 32 or 64 bit offsets (hashes)
Use 32-bit or 64-bit llseek() hashes for directory offsets depending on
the NFS version. NFSv2 gets 32-bit hashes only.

NOTE: This patch got rather complex as Christoph asked to set the
filp->f_mode flag in the open call or immediatly after dentry_open()
in nfsd_open() to avoid races.
Personally I still do not see a reason for that and in my opinion
FMODE_32BITHASH/FMODE_64BITHASH flags could be set nfsd_readdir(), as it
follows directly after nfsd_open() without a chance of races.

Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: J. Bruce Fields<bfields@redhat.com>
2012-03-18 22:44:50 -04:00
Bernd Schubert
999448a8c0 nfsd: rename 'int access' to 'int may_flags' in nfsd_open()
Just rename this variable, as the next patch will add a flag and
'access' as variable name would not be correct any more.

Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: J. Bruce Fields<bfields@redhat.com>
2012-03-18 22:44:49 -04:00
Fan Yong
d1f5273e9a ext4: return 32/64-bit dir name hash according to usage type
Traditionally ext2/3/4 has returned a 32-bit hash value from llseek()
to appease NFSv2, which can only handle a 32-bit cookie for seekdir()
and telldir().  However, this causes problems if there are 32-bit hash
collisions, since the NFSv2 server can get stuck resending the same
entries from the directory repeatedly.

Allow ext4 to return a full 64-bit hash (both major and minor) for
telldir to decrease the chance of hash collisions.  This still needs
integration on the NFS side.

Patch-updated-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
(blame me if something is not correct)

Signed-off-by: Fan Yong <yong.fan@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-18 22:44:40 -04:00
Jason Baron
93dc6107a7 Don't limit non-nested epoll paths
Commit 28d82dc1c4 ("epoll: limit paths") that I did to limit the
number of possible wakeup paths in epoll is causing a few applications
to longer work (dovecot for one).

The original patch is really about limiting the amount of epoll nesting
(since epoll fds can be attached to other fds). Thus, we probably can
allow an unlimited number of paths of depth 1. My current patch limits
it at 1000. And enforce the limits on paths that have a greater depth.

This is captured in: https://bugzilla.redhat.com/show_bug.cgi?id=681578

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-18 12:25:04 -07:00
Sachin Prabhu
e49a29bd0e Try using machine credentials for RENEW calls
Using user credentials for RENEW calls will fail when the user
credentials have expired.

To avoid this, try using the machine credentials when making RENEW
calls. If no machine credentials have been set, fall back to using user
credentials as before.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-17 11:17:42 -04:00
Trond Myklebust
9390f42546 NFSv4.1: Fix a few issues in filelayout_commit_pagelist
- Fix a race in which NFS_I(inode)->commits_outstanding could potentially
  go to zero (triggering a call to nfs_commit_clear_lock()) before we're
  done sending out all the commit RPC calls.

- If nfs_commitdata_alloc fails, there is no reason why we shouldn't
  try to send off all the commits-to-ds.

- Simplify the error handling.

- Change pnfs_commit_list() to always return either
  PNFS_ATTEMPTED or PNFS_NOT_ATTEMPTED.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
2012-03-17 11:17:42 -04:00
Trond Myklebust
8dd3775889 NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code
Move more pnfs-isms out of the generic commit code.

Bugfixes:

- filelayout_scan_commit_lists doesn't need to get/put the lseg.
  In fact since it is run under the inode->i_lock, the lseg_put()
  can deadlock.

- Ensure that we distinguish between what needs to be done for
  commit-to-data server and what needs to be done for commit-to-MDS
  using the new flag PG_COMMIT_TO_DS. Otherwise we may end up calling
  put_lseg() on a bucket for a struct nfs_page that got written
  through the MDS.

- Fix a case where we were using list_del() on an nfs_page->wb_list
  instead of list_del_init().

- filelayout_initiate_commit needs to call filelayout_commit_release
  on error instead of the mds_ops->rpc_release(). Otherwise it won't
  clear the commit lock.

Cleanups:

- Let the files layout manage the commit lists for the pNFS case.
  Don't expose stuff like pnfs_choose_commit_list, and the fact
  that the commit buckets hold references to the layout segment
  in common code.

- Cast out the put_lseg() calls for the struct nfs_read/write_data->lseg
  into the pNFS layer from whence they came.

- Let the pNFS layer manage the NFS_INO_PNFS_COMMIT bit.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
2012-03-17 11:09:33 -04:00
Linus Torvalds
cb1ecf25a8 Merge branch 'akpm' (more patches from Andrew)
Merge some more email patches from Andrew Morton:
 "A couple of nilfs fixes"

* emailed from Andrew Morton <akpm@linux-foundation.org>:
  nilfs2: fix NULL pointer dereference in nilfs_load_super_block()
  nilfs2: clamp ns_r_segments_percentage to [1, 99]
2012-03-16 17:14:55 -07:00
Ryusuke Konishi
d7178c79d9 nilfs2: fix NULL pointer dereference in nilfs_load_super_block()
According to the report from Slicky Devil, nilfs caused kernel oops at
nilfs_load_super_block function during mount after he shrank the
partition without resizing the filesystem:

 BUG: unable to handle kernel NULL pointer dereference at 00000048
 IP: [<d0d7a08e>] nilfs_load_super_block+0x17e/0x280 [nilfs2]
 *pde = 00000000
 Oops: 0000 [#1] PREEMPT SMP
 ...
 Call Trace:
  [<d0d7a87b>] init_nilfs+0x4b/0x2e0 [nilfs2]
  [<d0d6f707>] nilfs_mount+0x447/0x5b0 [nilfs2]
  [<c0226636>] mount_fs+0x36/0x180
  [<c023d961>] vfs_kern_mount+0x51/0xa0
  [<c023ddae>] do_kern_mount+0x3e/0xe0
  [<c023f189>] do_mount+0x169/0x700
  [<c023fa9b>] sys_mount+0x6b/0xa0
  [<c04abd1f>] sysenter_do_call+0x12/0x28
 Code: 53 18 8b 43 20 89 4b 18 8b 4b 24 89 53 1c 89 43 24 89 4b 20 8b 43
 20 c7 43 2c 00 00 00 00 23 75 e8 8b 50 68 89 53 28 8b 54 b3 20 <8b> 72
 48 8b 7a 4c 8b 55 08 89 b3 84 00 00 00 89 bb 88 00 00 00
 EIP: [<d0d7a08e>] nilfs_load_super_block+0x17e/0x280 [nilfs2] SS:ESP 0068:ca9bbdcc
 CR2: 0000000000000048

This turned out due to a defect in an error path which runs if the
calculated location of the secondary super block was invalid.

This patch fixes it and eliminates the reported oops.

Reported-by: Slicky Devil <slicky.dvl@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Slicky Devil <slicky.dvl@gmail.com>
Cc: <stable@vger.kernel.org>	[2.6.30+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-16 17:14:44 -07:00
Haogang Chen
3d777a6406 nilfs2: clamp ns_r_segments_percentage to [1, 99]
ns_r_segments_percentage is read from the disk.  Bogus or malicious
value could cause integer overflow and malfunction due to meaningless
disk usage calculation.  This patch reports error when mounting such
bogus volumes.

Signed-off-by: Haogang Chen <haogangchen@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-16 17:14:44 -07:00
Anton Blanchard
c017386352 afs: Remote abort can cause BUG in rxrpc code
When writing files to afs I sometimes hit a BUG:

kernel BUG at fs/afs/rxrpc.c:179!

With a backtrace of:

	afs_free_call
	afs_make_call
	afs_fs_store_data
	afs_vnode_store_data
	afs_write_back_from_locked_page
	afs_writepages_region
	afs_writepages

The cause is:

	ASSERT(skb_queue_empty(&call->rx_queue));

Looking at a tcpdump of the session the abort happens because we
are exceeding our disk quota:

	rx abort fs reply store-data error diskquota exceeded (32)

So the abort error is valid. We hit the BUG because we haven't
freed all the resources for the call.

By freeing any skbs in call->rx_queue before calling afs_free_call
we avoid hitting leaking memory and avoid hitting the BUG.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-16 17:01:41 -07:00
Anton Blanchard
2c724fb927 afs: Read of file returns EBADMSG
A read of a large file on an afs mount failed:

# cat junk.file > /dev/null
cat: junk.file: Bad message

Looking at the trace, call->offset wrapped since it is only an
unsigned short. In afs_extract_data:

        _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count);
...

        if (call->offset < count) {
                if (last) {
                        _leave(" = -EBADMSG [%d < %zu]", call->offset, count);
                        return -EBADMSG;
                }

Which matches the trace:

[cat   ] ==> afs_extract_data({65132},{524},1,,65536)
[cat   ] <== afs_extract_data() = -EBADMSG [0 < 65536]

call->offset went from 65132 to 0. Fix this by making call->offset an
unsigned int.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-16 17:01:41 -07:00
Seiji Aguchi
381b872cf7 pstore: Introduce get_reason_str() to pstore
Recently, there has been some changes in kmsg_dump() below and they have been applied to linus-tree.
 (1) kmsg_dump(KMSG_DUMP_KEXEC) was removed.
     http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=a3dd3323058d281abd584b15ad4c5b65064d7a61

 (2) The order of "enum kmsg_dump_reason" was modified.
     http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=c22ab332902333f83766017478c1ef6607ace681

Replace the fragile reason_str array with a more robust solution that
will not be broken by future re-arrangements of the enum values.

Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Link: https://lkml.org/lkml/2012/3/16/417
Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-03-16 15:36:59 -07:00
Rafael J. Wysocki
cf3bbcaf09 Merge branch 'pm-sleep'
* pm-sleep:
  PM / Sleep: JBD and JBD2 missing set_freezable()
2012-03-16 21:49:32 +01:00
Dave Chinner
f074211f60 xfs: fallback to vmalloc for large buffers in xfs_getbmap
xfs_getbmap uses for a large buffer for extents, which is kmalloc'd.
This can fail after the system has been running for some time as it
is a high order allocation. Add a fallback to vmalloc so that it
doesn't require contiguous memory and so won't randomly fail on
files with large extent lists.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-15 14:54:23 -05:00
Dave Chinner
ad650f5b27 xfs: fallback to vmalloc for large buffers in xfs_attrmulti_attr_get
xfsdump uses for a large buffer for extended attributes, which has a
kmalloc'd shadow buffer in the kernel. This can fail after the
system has been running for some time as it is a high order
allocation. Add a fallback to vmalloc so that it doesn't require
contiguous memory and so won't randomly fail while xfsdump is
running.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-15 14:14:33 -05:00
Dave Chinner
6eb2466036 xfs: remove remaining scraps of struct xfs_iomap
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-15 13:40:16 -05:00
Dave Chinner
f30d500f80 xfs: fix inode lookup race
When we get concurrent lookups of the same inode that is not in the
per-AG inode cache, there is a race condition that triggers warnings
in unlock_new_inode() indicating that we are initialising an inode
that isn't in a the correct state for a new inode.

When we do an inode lookup via a file handle or a bulkstat, we don't
serialise lookups at a higher level through the dentry cache (i.e.
pathless lookup), and so we can get concurrent lookups of the same
inode.

The race condition is between the insertion of the inode into the
cache in the case of a cache miss and a concurrently lookup:

Thread 1			Thread 2
xfs_iget()
  xfs_iget_cache_miss()
    xfs_iread()
    lock radix tree
    radix_tree_insert()
				rcu_read_lock
				radix_tree_lookup
				lock inode flags
				XFS_INEW not set
				igrab()
				unlock inode flags
				rcu_read_unlock
				use uninitialised inode
				.....
    lock inode flags
    set XFS_INEW
    unlock inode flags
    unlock radix tree
  xfs_setup_inode()
    inode flags = I_NEW
    unlock_new_inode()
      WARNING as inode flags != I_NEW

This can lead to inode corruption, inode list corruption, etc, and
is generally a bad thing to occur.

Fix this by setting XFS_INEW before inserting the inode into the
radix tree. This will ensure any concurrent lookup will find the new
inode with XFS_INEW set and that forces the lookup to wait until the
XFS_INEW flag is removed before allowing the lookup to succeed.

cc: <stable@vger.kernel.org> # for 3.0.x, 3.2.x
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-15 13:16:42 -05:00
Trond Myklebust
95a13f7b33 NFS: Fix a compile error when !defined NFS_DEBUG
We should use the 'ifdebug' wrapper rather than trying to inline
tests of nfs_debug, so that the code compiles correctly when we
don't define NFS_DEBUG.

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-14 21:55:01 -04:00
Linus Torvalds
f1cbd03f5e Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Been sitting on this for a while, but lets get this out the door.
  This fixes various important bugs for 3.3 final, along with a few more
  trivial ones.  Please pull!"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix ioc leak in put_io_context
  block, sx8: fix pointer math issue getting fw version
  Block: use a freezable workqueue for disk-event polling
  drivers/block/DAC960: fix -Wuninitialized warning
  drivers/block/DAC960: fix DAC960_V2_IOCTL_Opcode_T -Wenum-compare warning
  block: fix __blkdev_get and add_disk race condition
  block: Fix setting bio flags in drivers (sd_dif/floppy)
  block: Fix NULL pointer dereference in sd_revalidate_disk
  block: exit_io_context() should call elevator_exit_icq_fn()
  block: simplify ioc_release_fn()
  block: replace icq->changed with icq->flags
2012-03-14 17:16:45 -07:00
Dave Chinner
8d2a5e6ee3 xfs: clean up minor sparse warnings
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 13:21:17 -05:00
Christoph Hellwig
a05931ceb0 xfs: remove the global xfs_Gqm structure
If we initialize the slab caches for the quota code when XFS is loaded there
is no need for a global and reference counted quota manager structure.  Drop
all this overhead and also fix the error handling during quota initialization.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 12:06:32 -05:00
Christoph Hellwig
b84a3a9675 xfs: remove the per-filesystem list of dquots
Instead of keeping a separate per-filesystem list of dquots we can walk
the radix tree for the two places where we need to iterate all quota
structures.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 11:53:34 -05:00
Christoph Hellwig
9f920f1164 xfs: use per-filesystem radix trees for dquot lookup
Replace the global hash tables for looking up in-memory dquot structures
with per-filesystem radix trees to allow scaling to a large number of
in-memory dquot structures.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 11:09:06 -05:00
Christoph Hellwig
f8739c3ce2 xfs: per-filesystem dquot LRU lists
Replace the global dquot lru lists with a per-filesystem one.

Note that the shrinker isn't wire up to the per-superblock VFS shrinker
infrastructure as would have problems summing up and splitting the counts
for inodes and dquots.  I don't think this is a major problem as the quota
cache isn't as interwinded with the inode cache as the dentry cache is,
because an inode that is dropped from the cache will generally release
a dquot reference, but most of the time it won't be the last one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 11:09:06 -05:00
Christoph Hellwig
48776fd223 xfs: use common code for quota statistics
Switch the quota code over to use the generic XFS statistics infrastructure.
While the legacy /proc/fs/xfs/xqm and /proc/fs/xfs/xqmstats interfaces are
preserved for now the statistics that still have a meaning with the current
code are now also available from /proc/fs/xfs/stats.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-14 11:09:06 -05:00
William Dauchy
96dcadc2fd NFSv4: Rate limit the state manager for lock reclaim warning messages
Adding rate limit on `Lock reclaim failed` messages since it could fill
up system logs
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-14 09:25:26 -04:00
Boaz Harrosh
5318a29c19 pnfs-obj: Uglify objio_segment allocation for the sake of the principle :-(
At some past instance Linus Trovalds wrote:
> From: Linus Torvalds <torvalds@linux-foundation.org>
> commit a84a79e4d3 upstream.
>
> The size is always valid, but variable-length arrays generate worse code
> for no good reason (unless the function happens to be inlined and the
> compiler sees the length for the simple constant it is).
>
> Also, there seems to be some code generation problem on POWER, where
> Henrik Bakken reports that register r28 can get corrupted under some
> subtle circumstances (interrupt happening at the wrong time?).  That all
> indicates some seriously broken compiler issues, but since variable
> length arrays are bad regardless, there's little point in trying to
> chase it down.
>
> "Just don't do that, then".

Since then any use of "variable length arrays" has become blasphemous.
Even in perfectly good, beautiful, perfectly safe code like the one
below where the variable length arrays are only used as a sizeof()
parameter, for type-safe dynamic structure allocations. GCC is not
executing any stack allocation code.

I have produced a small file which defines two functions main1(unsigned numdevs)
and main2(unsigned numdevs). main1 uses code as before with call to malloc
and main2 uses code as of after this patch. I compiled it as:
	gcc -O2 -S see_asm.c
and here is what I get:

<see_asm.s>
main1:
.LFB7:
	.cfi_startproc
	mov	%edi, %edi
	leaq	4(%rdi,%rdi), %rdi
	salq	$3, %rdi
	jmp	malloc
	.cfi_endproc
.LFE7:
	.size	main1, .-main1
	.p2align 4,,15
	.globl	main2
	.type	main2, @function
main2:
.LFB8:
	.cfi_startproc
	mov	%edi, %edi
	addq	$2, %rdi
	salq	$4, %rdi
	jmp	malloc
	.cfi_endproc
.LFE8:
	.size	main2, .-main2
	.section	.text.startup,"ax",@progbits
	.p2align 4,,15
</see_asm.s>

*Exact* same code !!!

So please seriously consider not accepting this patch and leave the
perfectly good code intact.

CC: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-13 23:47:59 -04:00
Jan Kara
3339578f05 jbd2: cleanup journal tail after transaction commit
Normally, we have to issue a cache flush before we can update journal tail in
journal superblock, effectively wiping out old transactions from the journal.
So use the fact that during transaction commit we issue cache flush anyway and
opportunistically push journal tail as far as we can. Since update of journal
superblock is still costly (we have to use WRITE_FUA), we update log tail only
if we can free significant amount of space.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:45:38 -04:00
Jan Kara
932bb305ba jbd2: remove bh_state lock from checkpointing code
All accesses to checkpointing entries in journal_head are protected
by j_list_lock. Thus __jbd2_journal_remove_checkpoint() doesn't really
need bh_state lock.

Also the only part of journal head that the rest of checkpointing code
needs to check is jh->b_transaction which is safe to read under
j_list_lock.

So we can safely remove bh_state lock from all of checkpointing code which
makes it considerably prettier.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:45:25 -04:00
Jan Kara
c254c9ec14 jbd2: remove always true condition in __journal_try_to_free_buffer()
The check b_jlist == BJ_None in __journal_try_to_free_buffer() is
always true (__jbd2_journal_temp_unlink_buffer() also checks this in
an assertion) so just remove it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:27:44 -04:00
Jan Kara
5bebccf901 jbd2: declare __jbd2_journal_temp_unlink_buffer() static
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:25:06 -04:00
Jan Kara
96c866782b jbd2: fix BH_JWrite setting in checkpointing code
BH_JWrite bit should be set when buffer is written to the journal. So
checkpointing shouldn't set this bit when writing out buffer. This didn't
cause any observable bug since BH_JWrite bit is used only for debugging
purposes but it's good to have this consistent.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:24:54 -04:00
Jan Kara
79feb521a4 jbd2: issue cache flush after checkpointing even with internal journal
When we reach jbd2_cleanup_journal_tail(), there is no guarantee that
checkpointed buffers are on a stable storage - especially if buffers were
written out by jbd2_log_do_checkpoint(), they are likely to be only in disk's
caches. Thus when we update journal superblock effectively removing old
transaction from journal, this write of superblock can get to stable storage
before those checkpointed buffers which can result in filesystem corruption
after a crash. Thus we must unconditionally issue a cache flush before we
update journal superblock in these cases.

A similar problem can also occur if journal superblock is written only in
disk's caches, other transaction starts reusing space of the transaction
cleaned from the log and power failure happens. Subsequent journal replay would
still try to replay the old transaction but some of it's blocks may be already
overwritten by the new transaction. For this reason we must use WRITE_FUA when
updating log tail and we must first write new log tail to disk and update
in-memory information only after that.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 22:22:54 -04:00
Linus Torvalds
8e8bb96d24 Merge git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fixes from Steve French.

* git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Do not kmalloc under the flocks spinlock
  cifs: possible memory leak in xattr.
2012-03-13 17:03:53 -07:00
Christoph Hellwig
8f639ddea0 xfs: reimplement fdatasync support
Add an in-memory only flag to say we logged timestamps only, and use it to
check if fdatasync can optimize away the log force.

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>
2012-03-13 17:18:14 -05:00
Christoph Hellwig
f5d8d5c4bf xfs: split in-core and on-disk inode log item fields
Add a new ili_fields member to the inode log item to isolate the in-memory
flags from the ones that actually go to the log.  This will allow tracking
timestamp-only updates for fdatasync and O_DSYNC in the next patch and
prepares for divorcing the on-disk log format from the in-memory log item
a little further down the road.

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>
2012-03-13 17:08:17 -05:00
Christoph Hellwig
339a5f5dd9 xfs: make xfs_inode_item_size idempotent
Move all code messing with the inode log item flags into xfs_inode_item_format
to make sure xfs_inode_item_size really only calculates the the number of
vectors, but doesn't modify any state of the inode item.

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>
2012-03-13 17:05:08 -05:00
Christoph Hellwig
8a9c9980f2 xfs: log timestamp updates
Timestamps on regular files are the last metadata that XFS does not update
transactionally.  Now that we use the delaylog mode exclusively and made
the log scode scale extremly well there is no need to bypass that code for
timestamp updates.  Logging all updates allows to drop a lot of code, and
will allow for further performance improvements later on.

Note that this patch drops optimized handling of fdatasync - it will be
added back in a separate commit.

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>
2012-03-13 17:01:15 -05:00
Nigel Cunningham
35c80422af PM / Sleep: JBD and JBD2 missing set_freezable()
With the latest and greatest changes to the freezer, I started seeing
panics that were caused by jbd2 running post-process freezing and
hitting the canary BUG_ON for non-TuxOnIce I/O submission. I've traced
this back to a lack of set_freezable calls in both jbd and jbd2. Since
they're clearly meant to be frozen (there are tests for freezing()), I
submit the following patch to add the missing calls.

Signed-off-by: Nigel Cunningham <nigel@tuxonice.net>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-13 22:36:44 +01:00
Christoph Hellwig
281627df3e xfs: log file size updates at I/O completion time
Do not use unlogged metadata updates and the VFS dirty bit for updating
the file size after writeback.  In addition to causing various problems
with updates getting delayed for far too long this also drags in the
unscalable VFS dirty tracking, and is one of the few remaining unlogged
metadata updates.

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>
2012-03-13 16:30:49 -05:00
Jan Kara
a78bb11d7a jbd2: protect all log tail updates with j_checkpoint_mutex
There are some log tail updates that are not protected by j_checkpoint_mutex.
Some of these are harmless because they happen during startup or shutdown but
updates in jbd2_journal_commit_transaction() and jbd2_journal_flush() can
really race with other log tail updates (e.g. someone doing
jbd2_journal_flush() with someone running jbd2_cleanup_journal_tail()). So
protect all log tail updates with j_checkpoint_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 15:43:04 -04:00
Jan Kara
24bcc89c7e jbd2: split updating of journal superblock and marking journal empty
There are three case of updating journal superblock. In the first case, we want
to mark journal as empty (setting s_sequence to 0), in the second case we want
to update log tail, in the third case we want to update s_errno. Split these
cases into separate functions. It makes the code slightly more straightforward
and later patches will make the distinction even more important.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-13 15:41:04 -04:00