Commit Graph

34180 Commits

Author SHA1 Message Date
Linus Torvalds
57498f9cb9 Quiet static checkers by removing unneeded conditionals
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.14 (GNU/Linux)
 
 iQIcBAABCgAGBQJSj6OkAAoJENaSAD2qAscK9ukP/Ar6Lracra9IViBvFRIgBGnf
 K0jUwF0atd9Uj+E7phUzG2cfTKHqCVHYHfP/tCSurjjQnb9TpQ1ZkFy22VGrlDYK
 jrU39wOfQQCQX+pPmJIX2L3W5ZAEFbBMgJZ7PaIM1qDV9cjy+mt/iNHJrH0BHBH4
 HryvCMeALRR5elwYkhfTql4VN2ClS9veAWdcGhAsbZ8vaNB01x+9Wps+t/VPiCVp
 +K3C+mC/LennTzdmDJUIbMFbKSsTjrdynRtuPLeSgVAA6Y05ps5vf+hoNmiLmphJ
 z1j0HCht1FApM8VrllRmJla8vo6DRoqn+DUqRRuoI7kE5zFS61x5EIpogGdqmhn/
 9zYA9xdj7Fpw/57G3xSpUdpS5u0JsxETc580iitl1tDgEHcQEgmRSCa89uhaaDFi
 pSKgV7au5DqJdBtTDvWeQPAKrkT9LWOsrlEXX5aqM8wIs8FheIPZMEz11m6vMp6n
 e9geohCvpLL0opUx209ofpYHpYLS6IXY/LrQeHSYeZ2DYGyDZ7R/KHt8GN1NwLrE
 AUJTOzdq3H37ZDlmkcTEO9z84qfgaHioiHGlzYcCfzR6aw6cey1jOj8Y9lg0gciQ
 nWuWXtES0UtvpR9w84nbXCpgOrQMYpGOhqvduDALa+7XhbDhpFtmN9e4f9CfTumv
 PYQ9hYRKD3w6iWsoYubd
 =IgXu
 -----END PGP SIGNATURE-----

Merge tag 'ecryptfs-3.13-rc1-quiet-checkers' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull minor eCryptfs fix from Tyler Hicks:
 "Quiet static checkers by removing unneeded conditionals"

* tag 'ecryptfs-3.13-rc1-quiet-checkers' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: file->private_data is always valid
2013-11-22 10:58:14 -08:00
Linus Torvalds
d0f278c1dd Merge git://git.kvack.org/~bcrl/aio-next
Pull aio fixes from Benjamin LaHaise.

* git://git.kvack.org/~bcrl/aio-next:
  aio: nullify aio->ring_pages after freeing it
  aio: prevent double free in ioctx_alloc
  aio: Fix a trinity splat
2013-11-22 08:42:14 -08:00
Linus Torvalds
533db9b3d4 Merge branch 'for-3.13' of git://linux-nfs.org/~bfields/linux
Pull nfsd bugfixes from Bruce Fields:
 "A couple nfsd bugfixes"

* 'for-3.13' of git://linux-nfs.org/~bfields/linux:
  nfsd4: fix xdr decoding of large non-write compounds
  nfsd: make sure to balance get/put_write_access
  nfsd: split up nfsd_setattr
2013-11-22 08:41:17 -08:00
Linus Torvalds
c85e07278e A couple of small, but important bug fixes for GFS2. The first one
fixes a possible NULL pointer dereference, and the second one
 resolves a reference counting issue in one of the lesser used paths
 through atomic_open.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.15 (GNU/Linux)
 
 iQIcBAABAgAGBQJSjy+IAAoJEMrg3m4a/8jSy4wP+wXU26Hbj0nIkzxEokxgQLO/
 64flbmRx/960CAEFiFWhrSQUIpb2R2Lw1tNGiRiAhch4wLmRrKMEZnR/dI57KaMR
 /dcm78q2aPbNvdB/5pxrTQx8bkRYcVOCZdD7lizUUHs/oLIhl0IZ4uGSOy0kUdTd
 gcgus1Rd7mPJp+Smr33W7rPB6WAfo6+iAn7RNcdxgRcH2Ng8BZm82Z4Gn8TDN3H1
 cZ8yzFbycLvj67kpkdEesjaDTQv/zWrtNg/ocVDGbPRxykzf89v94LpodZkpvRAz
 vvCT7MNy9R8konDcGImSV6zRstYFtQwg8hqzIvSgla6yppghpGXRp9c7PpPDNzc9
 ynVvZqc0MbZeTlGt5/DQW6QmFKwgJcT/tJSaDdx1NRoHQTOXzSM9hw5it048Hm8L
 AUrsAvFJtTtm7Uwd7CE78IvrOQWNl0EAgw20twKR1GR6dnGmvvaVFrLXSacCNsFm
 VkOs6QLRoax6DbjHgC0ERka5J7YcGniNff+vx2ndRkth3KWv3N8fqh43mBtuQcRN
 yzAffJMXYGWWBHvaXR71dJ35Z4lFbMfKU+oPZokucl9c1dnFJ26cqVKMlhD+hUGK
 ms0qVDiRf4C8qhIyWor1FqWCGeFlXwtTzgGtoovrOoWJxqp6vLdwFjEEPKb1Tlai
 pBmD16Z3ehx8I76Yzgjx
 =aMoW
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes

Pull GFS2 fixes from Steven Whitehouse:
 "A couple of small, but important bug fixes for GFS2.  The first one
  fixes a possible NULL pointer dereference, and the second one resolves
  a reference counting issue in one of the lesser used paths through
  atomic_open"

* tag 'gfs2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes:
  GFS2: Fix ref count bug relating to atomic_open
  GFS2: fix potential NULL pointer dereference
2013-11-22 08:39:44 -08:00
Linus Torvalds
fb0d1eb892 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Almost all of these are bug fixes.  Dave Sterba's documentation update
  is the big exception because he removed our promises to set any
  machine running Btrfs on fire"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Documentation: filesystems: update btrfs tools section
  Documentation: filesystems: add new btrfs mount options
  btrfs: update kconfig help text
  btrfs: fix bio_size_ok() for max_sectors > 0xffff
  btrfs: Use trace condition for get_extent tracepoint
  btrfs: fix typo in the log message
  Btrfs: fix list delete warning when removing ordered root from the list
  Btrfs: print bytenr instead of page pointer in check-int
  Btrfs: remove dead codes from ctree.h
  Btrfs: don't wait for ordered data outside desired range
  Btrfs: fix lockdep error in async commit
  Btrfs: avoid heavy operations in btrfs_commit_super
  Btrfs: fix __btrfs_start_workers retval
  Btrfs: disable online raid-repair on ro mounts
  Btrfs: do not inc uncorrectable_errors counter on ro scrubs
  Btrfs: only drop modified extents if we logged the whole inode
  Btrfs: make sure to copy everything if we rename
  Btrfs: don't BUG_ON() if we get an error walking backrefs
2013-11-22 08:38:55 -08:00
Linus Torvalds
6ea9786e76 xfs: update #2 for v3.13-rc1
Here we have a performance fix for inode iversion, increased inode cluster size
 for v5 superblock filesystems, a fix for error handling in
 xfs_bmap_add_attrfork, and a MAINTAINERS update to add Dave.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.10 (GNU/Linux)
 
 iQIcBAABAgAGBQJSjjbHAAoJENaLyazVq6ZO/l4QAIajqdOy56MDDCaE1ocNRMej
 oPXqxMZpi+YAFRXIWQK/evjXjYE4hcCjiLI0tAKzQM0FGRHd1GgQQJvWKjvHBrLG
 rlrHWDcKq+3bsJ6KIw+JvLnhsOxxKXbRovIG1PI4frOeFtS3DCtzMZ4FGBErh+BV
 PkFjf5Lxe7VnegDL4eNpkAfSM/2/pEtn2gIMMj8eeKemTPAbDplMAk4UUxp18R7F
 FCr6mOKETWthHdBgkLB1xA6OVGUuYcleWvluFc5PONJN1VPSutEHJaRw01lY1VLY
 4COUt7MjLAqlAu24LTD1aNszhUlajYq0AL+nmd4gULZI2fpu+meUIGCHQG4BpVZl
 ds9isn80SmKiLT4ZQCbJAv4XMEXn6p41+uxdKP6ZkYXso4zJmVw0TyGLg/ZOJpw0
 9mNcaJG1s57ronN07dMCSMqsyNFLuLtX7+mVa5liO3sEkXv7hEK7EB9qojQ9Qn/p
 xC2r4jrE0//xgcbOE+uKOyIad3L0IBM6TXuy58xVPi5l0dpM69z4LCyUGZ+L1G8x
 0QhkA7NL3xI2tNgehzJBsBuxjtEePtm/jCIS1HfDSIRQZR3y+PxVEjgO4naS4vm2
 xKwo5dBodsxgXeSMUY3miMuEX7ZQse+xVDK1q0Zk4VXZyC2+erNS5hxs313yzeLD
 7X2ZESfIJaMrkLSKOVUe
 =w0M3
 -----END PGP SIGNATURE-----

Merge tag 'xfs-for-linus-v3.13-rc1-2' of git://oss.sgi.com/xfs/xfs

Pull second xfs update from Ben Myers:
 "There are a couple of patches that I wasn't quite sure about in time
  for our initial 3.13 pull request, a bugfix, and an update to add Dave
  to MAINTAINERS:

  Here we have a performance fix for inode iversion, increased inode
  cluster size for v5 superblock filesystems, a fix for error handling
  in xfs_bmap_add_attrfork, and a MAINTAINERS update to add Dave"

* tag 'xfs-for-linus-v3.13-rc1-2' of git://oss.sgi.com/xfs/xfs:
  xfs: open code inc_inode_iversion when logging an inode
  xfs: increase inode cluster size for v5 filesystems
  xfs: fix unlock in xfs_bmap_add_attrfork
  xfs: update maintainers
2013-11-22 08:37:47 -08:00
Linus Torvalds
a5d6e63323 Merge branch 'akpm' (fixes from Andrew)
Merge patches from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: place page->pmd_huge_pte to right union
  MAINTAINERS: add keyboard driver to Hyper-V file list
  x86, mm: do not leak page->ptl for pmd page tables
  ipc,shm: correct error return value in shmctl (SHM_UNLOCK)
  mm, mempolicy: silence gcc warning
  block/partitions/efi.c: fix bound check
  ARM: drivers/rtc/rtc-at91rm9200.c: disable interrupts at shutdown
  mm: hugetlbfs: fix hugetlbfs optimization
  kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS cleanly
  ipc,shm: fix shm_file deletion races
  mm: thp: give transparent hugepage code a separate copy_page
  checkpatch: fix "Use of uninitialized value" warnings
  configfs: fix race between dentry put and lookup
2013-11-21 21:32:38 -08:00
Linus Torvalds
3eaded86ac Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
 "Nothing amazing.  Formatting, small bug fixes, couple of fixes where
  we didn't get records due to some old VFS changes, and a change to how
  we collect execve info..."

Fixed conflict in fs/exec.c as per Eric and linux-next.

* git://git.infradead.org/users/eparis/audit: (28 commits)
  audit: fix type of sessionid in audit_set_loginuid()
  audit: call audit_bprm() only once to add AUDIT_EXECVE information
  audit: move audit_aux_data_execve contents into audit_context union
  audit: remove unused envc member of audit_aux_data_execve
  audit: Kill the unused struct audit_aux_data_capset
  audit: do not reject all AUDIT_INODE filter types
  audit: suppress stock memalloc failure warnings since already managed
  audit: log the audit_names record type
  audit: add child record before the create to handle case where create fails
  audit: use given values in tty_audit enable api
  audit: use nlmsg_len() to get message payload length
  audit: use memset instead of trying to initialize field by field
  audit: fix info leak in AUDIT_GET requests
  audit: update AUDIT_INODE filter rule to comparator function
  audit: audit feature to set loginuid immutable
  audit: audit feature to only allow unsetting the loginuid
  audit: allow unsetting the loginuid (with priv)
  audit: remove CONFIG_AUDIT_LOGINUID_IMMUTABLE
  audit: loginuid functions coding style
  selinux: apply selinux checks on new audit message types
  ...
2013-11-21 19:18:14 -08:00
Junxiao Bi
76ae281f63 configfs: fix race between dentry put and lookup
A race window in configfs, it starts from one dentry is UNHASHED and end
before configfs_d_iput is called.  In this window, if a lookup happen,
since the original dentry was UNHASHED, so a new dentry will be
allocated, and then in configfs_attach_attr(), sd->s_dentry will be
updated to the new dentry.  Then in configfs_d_iput(),
BUG_ON(sd->s_dentry != dentry) will be triggered and system panic.

sys_open:                     sys_close:
 ...                           fput
                                dput
                                 dentry_kill
                                  __d_drop <--- dentry unhashed here,
                                           but sd->dentry still point
                                           to this dentry.

 lookup_real
  configfs_lookup
   configfs_attach_attr---> update sd->s_dentry
                            to new allocated dentry here.

                                   d_kill
                                     configfs_d_iput <--- BUG_ON(sd->s_dentry != dentry)
                                                     triggered here.

To fix it, change configfs_d_iput to not update sd->s_dentry if
sd->s_count > 2, that means there are another dentry is using the sd
beside the one that is going to be put.  Use configfs_dirent_lock in
configfs_attach_attr to sync with configfs_d_iput.

With the following steps, you can reproduce the bug.

1. enable ocfs2, this will mount configfs at /sys/kernel/config and
   fill configure in it.

2. run the following script.
	while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &
	while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-21 16:42:27 -08:00
Steven Whitehouse
ea0341e071 GFS2: Fix ref count bug relating to atomic_open
In the case that atomic_open calls finish_no_open() with
the dentry that was supplied to gfs2_atomic_open() an
extra reference count is required. This patch fixes that
issue preventing a bug trap triggering at umount time.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2013-11-21 18:47:57 +00:00
Michal Nazarewicz
e3c4269d13 GFS2: fix potential NULL pointer dereference
Commit [e66cf1610: GFS2: Use lockref for glocks] replaced call:
    atomic_read(&gi->gl->gl_ref) == 0
with:
    __lockref_is_dead(&gl->gl_lockref)
therefore changing how gl is accessed, from gi->gl to plan gl.
However, gl can be a NULL pointer, and so gi->gl needs to be
used instead (which is guaranteed not to be NULL because fo
the while loop checking that condition).

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2013-11-21 09:55:45 +00:00
David Sterba
4204617d14 btrfs: update kconfig help text
Reflect the current status. Portions of the text taken from the
wiki pages.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:49:09 -05:00
Akinobu Mita
475bf36ffb btrfs: fix bio_size_ok() for max_sectors > 0xffff
The data type of max_sectors in queue settings is unsigned int.  But
this value is stored to the local variable whose type is unsigned short
in bio_size_ok().  This can cause unexpected result when max_sectors >
0xffff.

Cc: Chris Mason <chris.mason@fusionio.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:48:44 -05:00
Steven Rostedt
4cd8587ce8 btrfs: Use trace condition for get_extent tracepoint
Doing an if statement to test some condition to know if we should
trigger a tracepoint is pointless when tracing is disabled. This just
adds overhead and wastes a branch prediction. This is why the
TRACE_EVENT_CONDITION() was created. It places the check inside the jump
label so that the branch does not happen unless tracing is enabled.

That is, instead of doing:

	if (em)
		trace_btrfs_get_extent(root, em);

Which is basically this:

	if (em)
		if (static_key(trace_btrfs_get_extent)) {

Using a TRACE_EVENT_CONDITION() we can just do:

	trace_btrfs_get_extent(root, em);

And the condition trace event will do:

	if (static_key(trace_btrfs_get_extent)) {
		if (em) {
			...

The static key is a non conditional jump (or nop) that is faster than
having to check if em is NULL or not.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:47 -05:00
Anand Jain
52a1575921 btrfs: fix typo in the log message
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:47 -05:00
Miao Xie
931aa87791 Btrfs: fix list delete warning when removing ordered root from the list
Commit b02441999e "Btrfs: don't wait for
the completion of all the ordered extents" introduced a bug that broke
the ordered root list:
 WARNING: CPU: 1 PID: 7119 at lib/list_debug.c:59 __list_del_entry+0x5a/0x98()

It is because we forgot to return the roots in the splice list to the
ordered list of the fs. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:46 -05:00
Stefan Behrens
56d140f5f6 Btrfs: print bytenr instead of page pointer in check-int
The page pointer information was useless. The bytenr is what you
want when you search for submitted write bios.

Additionally, a new bit in the print mask is added that allows
to selectively enable the check-int submit_bio verbose mode. Before,
the global verbose mode had to be enabled leading to many million
useless lines in the kernel log.

And a comment is added that explains that LOG_BUF_SHIFT needs to
be set to a really high value.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:46 -05:00
Wang Shilong
9650e05c07 Btrfs: remove dead codes from ctree.h
These two functions are only stated but undefined.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:45 -05:00
Filipe David Borba Manana
b52abf1e3b Btrfs: don't wait for ordered data outside desired range
In btrfs_wait_ordered_range(), if we found an extent to the left
of the start of our desired wait range and the last byte of that
extent is 1 less than the desired range's start, we would would
wait for the IO completion of that extent unnecessarily.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:45 -05:00
Liu Bo
b1a06a4b57 Btrfs: fix lockdep error in async commit
Lockdep complains about btrfs's async commit:

[ 2372.462171] [ BUG: bad unlock balance detected! ]
[ 2372.462191] 3.12.0+ #32 Tainted: G        W
[ 2372.462209] -------------------------------------
[ 2372.462228] ceph-osd/14048 is trying to release lock (sb_internal) at:
[ 2372.462275] [<ffffffffa022cb10>] btrfs_commit_transaction_async+0x1b0/0x2a0 [btrfs]
[ 2372.462305] but there are no more locks to release!
[ 2372.462324]
[ 2372.462324] other info that might help us debug this:
[ 2372.462349] no locks held by ceph-osd/14048.
[ 2372.462367]
[ 2372.462367] stack backtrace:
[ 2372.462386] CPU: 2 PID: 14048 Comm: ceph-osd Tainted: G        W    3.12.0+ #32
[ 2372.462414] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080015  11/09/2011
[ 2372.462455]  ffffffffa022cb10 ffff88007490fd28 ffffffff816f094a ffff8800378aa320
[ 2372.462491]  ffff88007490fd50 ffffffff810adf4c ffff8800378aa320 ffff88009af97650
[ 2372.462526]  ffffffffa022cb10 ffff88007490fd88 ffffffff810b01ee ffff8800898c0000
[ 2372.462562] Call Trace:
[ 2372.462584]  [<ffffffffa022cb10>] ? btrfs_commit_transaction_async+0x1b0/0x2a0 [btrfs]
[ 2372.462619]  [<ffffffff816f094a>] dump_stack+0x45/0x56
[ 2372.462642]  [<ffffffff810adf4c>] print_unlock_imbalance_bug+0xec/0x100
[ 2372.462677]  [<ffffffffa022cb10>] ? btrfs_commit_transaction_async+0x1b0/0x2a0 [btrfs]
[ 2372.462710]  [<ffffffff810b01ee>] lock_release+0x18e/0x210
[ 2372.462742]  [<ffffffffa022cb36>] btrfs_commit_transaction_async+0x1d6/0x2a0 [btrfs]
[ 2372.462783]  [<ffffffffa025a7ce>] btrfs_ioctl_start_sync+0x3e/0xc0 [btrfs]
[ 2372.462822]  [<ffffffffa025f1d3>] btrfs_ioctl+0x4c3/0x1f70 [btrfs]
[ 2372.462849]  [<ffffffff812c0321>] ? avc_has_perm+0x121/0x1b0
[ 2372.462873]  [<ffffffff812c0224>] ? avc_has_perm+0x24/0x1b0
[ 2372.462897]  [<ffffffff8107ecc8>] ? sched_clock_cpu+0xa8/0x100
[ 2372.462922]  [<ffffffff8117b145>] do_vfs_ioctl+0x2e5/0x4e0
[ 2372.462946]  [<ffffffff812c19e6>] ? file_has_perm+0x86/0xa0
[ 2372.462969]  [<ffffffff8117b3c1>] SyS_ioctl+0x81/0xa0
[ 2372.462991]  [<ffffffff817045a4>] tracesys+0xdd/0xe2

====================================================

It's because that we don't do the right thing when checking if it's ok to
tell lockdep that we're trying to release the rwsem.

If the trans handle's type is TRANS_ATTACH, we won't acquire the freeze rwsem, but
as TRANS_ATTACH fits the check (trans < TRANS_JOIN_NOLOCK), we'll release the freeze
rwsem, which makes lockdep complains a lot.

Reported-by: Ma Jianpeng <majianpeng@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:44 -05:00
Liu Bo
d52c1bcc64 Btrfs: avoid heavy operations in btrfs_commit_super
The 'git blame' history shows that, the old transaction commit code has to do
twice to ensure roots are updated and we have to flush metadata and super block
manually, however, right now all of these can be handled well inside
the transaction commit code without extra efforts.

And the error handling part remains same with the current code, -- 'return to
caller once we get error'.

This saves us a transaction commit and a flush of super block, which are both
heavy operations according to ftrace output analysis.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:42:16 -05:00
Ilya Dryomov
ba69994a40 Btrfs: fix __btrfs_start_workers retval
__btrfs_start_workers returns 0 in case it raced with
btrfs_stop_workers and lost the race.  This is wrong because worker in
this case is not allowed to start and is in fact destroyed.  Return
-EINVAL instead.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:42:11 -05:00
Ilya Dryomov
908960c6c0 Btrfs: disable online raid-repair on ro mounts
This disables the "if needed, write the good copy back before the read
is completed" part of the read sequence for read-only mounts.

Cc: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:42:05 -05:00
Ilya Dryomov
33ef30add1 Btrfs: do not inc uncorrectable_errors counter on ro scrubs
Currently if we discover an error when scrubbing in ro mode we a)
blindly increment the uncorrectable_errors counter, and b) spam the
dmesg with the 'unable to fixup (regular) error at ...' message, even
though a) we haven't tried to determine if the error is correctable or
not, and b) we haven't tried to fixup anything.  Fix this.

Cc: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:41:38 -05:00
Josef Bacik
d006a04816 Btrfs: only drop modified extents if we logged the whole inode
If we fsync, seek and write, rename and then fsync again we will lose the
modified hole extent because the rename will drop all of the modified extents
since we didn't do the fast search.  We need to only drop the modified extents
if we didn't do the fast search and we were logging the entire inode as we don't
need them anymore, otherwise this is being premature.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:41:32 -05:00
Josef Bacik
6cfab851f4 Btrfs: make sure to copy everything if we rename
If we rename a file that is already in the log and we fsync again we will lose
the new name.  This is because we just log the inode update and not the new ref.
To fix this we just need to check if we are logging the new name of the inode
and copy all the metadata instead of just updating the inode itself.  With this
patch my testcase now passes.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:41:24 -05:00
Josef Bacik
4724b106b9 Btrfs: don't BUG_ON() if we get an error walking backrefs
We can just return false for this so we stop doing the snapshot aware defrag
stuff.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:41:16 -05:00
Linus Torvalds
af2e2f3280 These patches optionally improve the multi-threading peformance
of Squashfs by adding parallel decompression, and direct
 decompression into the page cache, eliminating an intermediate
 buffer (removing memcpy overhead and lock contention).
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJSjP25AAoJEJAch/D1fbHUsFAQAJjpCfWyv7JfNtJSUk20UgbC
 kQvpMUbISwrLnszW6ooWBJxQ4OCyQ3AWN5yrAk6hb86oR0SN33WAJjqW5hR5htOy
 5ZMs3OnzE3haUej+Xxw/VTK61FoOq/PjK8UZ6NBfhdnihfE/fQykrgDhHznJ68iq
 0wWeqTY68sF5ZBQ2kKhBSfF+lGlWeLqhiFGOq68MAv4Rd8dGZsiLIFG7JQsrwmAn
 cswmiCTQppGGz/+6FBWvaEEpD+nUCX/h/1XKwMhuzWwZZTFWPM+BkEfMOKv78txW
 GWn/o1/kWA/u1f5V+nZlUhNtj+KCU11YZfTAJ30Ie1erzKCh8DGcLhCyfC0N+Hw/
 Na5vxyjEnTdJoBnRbcPpHcGwPB0J5Q2nCzu1b/3blUGdpXQrNp/zZ4hg53fYEKHy
 2KAf9j5rqs85IqoKwrzeod/V1WakjMQJPntoJ2r7ILP4lKfvOHt6m1D5/7tVodxZ
 mGa8eaQtH5SrtnLldKo4vGgh65/ViQ2cVlAbGC7I9rfXJ0fITYO8PvKBTcXvtOHc
 +rjCnoOHtSv8FvFf1G9qfbBMwaC+3n95rYSac0Ibl6O7x2pdQusUmiuyUf1NXsDg
 V4ENspn/DTrltZbTbBTgI3LizxvJOMtf72zo+Bhghitp09yeIFfieVqM/kuR74Ym
 O4EaVGcFdXJJc3UmK/69
 =lV/M
 -----END PGP SIGNATURE-----

Merge tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next

Pull squashfs updates from Phillip Lougher:
 "These patches optionally improve the multi-threading peformance of
  Squashfs by adding parallel decompression, and direct decompression
  into the page cache, eliminating an intermediate buffer (removing
  memcpy overhead and lock contention)"

* tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next:
  Squashfs: Check stream is not NULL in decompressor_multi.c
  Squashfs: Directly decompress into the page cache for file data
  Squashfs: Restructure squashfs_readpage()
  Squashfs: Generalise paging handling in the decompressors
  Squashfs: add multi-threaded decompression using percpu variable
  squashfs: Enhance parallel I/O
  Squashfs: Refactor decompressor interface and code
2013-11-20 14:51:37 -08:00
Linus Torvalds
b5898cd057 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs bits and pieces from Al Viro:
 "Assorted bits that got missed in the first pull request + fixes for a
  couple of coredump regressions"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fold try_to_ascend() into the sole remaining caller
  dcache.c: get rid of pointless macros
  take read_seqbegin_or_lock() and friends to seqlock.h
  consolidate simple ->d_delete() instances
  gfs2: endianness misannotations
  dump_emit(): use __kernel_write(), not vfs_write()
  dump_align(): fix the dumb braino
2013-11-20 14:25:39 -08:00
Linus Torvalds
5a1efc6e68 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block IO fixes from Jens Axboe:
 "Normally I'd defer my initial for-linus pull request until after the
  merge window, but a race was uncovered in the virtio-blk conversion to
  blk-mq that could cause hangs.  So here's a small collection of fixes
  for you to pull:

   - The fix for the virtio-blk IO hang reported by Dave Chinner, from
     Shaohua and myself.

   - Add the Insert blktrace event for blk-mq.  This makes 'btt' happy
     when it is doing it's state transition analysis.

   - Ensure that blk-mq has disk/partition stats enabled by default,
     instead of making it opt-in.

   - A fix for __bio_add_page() and large sector counts"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq: add blktrace insert event trace
  virtio-blk: virtqueue_kick() must be ordered with other virtqueue operations
  blk-mq: ensure that we set REQ_IO_STAT so diskstats work
  bio: fix argument of __bio_add_page() for max_sectors > 0xffff
2013-11-20 13:06:20 -08:00
Phillip Lougher
ed4f381ec1 Squashfs: Check stream is not NULL in decompressor_multi.c
Fix static checker complaint that stream is not checked in
squashfs_decompressor_destroy().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2013-11-20 03:59:20 +00:00
Phillip Lougher
0d455c12c6 Squashfs: Directly decompress into the page cache for file data
This introduces an implementation of squashfs_readpage_block()
that directly decompresses into the page cache.

This uses the previously added page handler abstraction to push
down the necessary kmap_atomic/kunmap_atomic operations on the
page cache buffers into the decompressors.  This enables
direct copying into the page cache without using the slow
kmap/kunmap calls.

The code detects when multiple threads are racing in
squashfs_readpage() to decompress the same block, and avoids
this regression by falling back to using an intermediate
buffer.

This patch enhances the performance of Squashfs significantly
when multiple processes are accessing the filesystem simultaneously
because it not only reduces memcopying, but it more importantly
eliminates the lock contention on the intermediate buffer.

Using single-thread decompression.

        dd if=file1 of=/dev/null bs=4096 &
        dd if=file2 of=/dev/null bs=4096 &
        dd if=file3 of=/dev/null bs=4096 &
        dd if=file4 of=/dev/null bs=4096

Before:

629145600 bytes (629 MB) copied, 45.8046 s, 13.7 MB/s

After:

629145600 bytes (629 MB) copied, 9.29414 s, 67.7 MB/s

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2013-11-20 03:59:13 +00:00
Phillip Lougher
5f55dbc0c5 Squashfs: Restructure squashfs_readpage()
Restructure squashfs_readpage() splitting it into separate
functions for datablocks, fragments and sparse blocks.

Move the memcpying (from squashfs cache entry) implementation of
squashfs_readpage_block into file_cache.c

This allows different implementations to be supported.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2013-11-20 03:59:07 +00:00
Phillip Lougher
846b730e99 Squashfs: Generalise paging handling in the decompressors
Further generalise the decompressors by adding a page handler
abstraction.  This adds helpers to allow the decompressors
to access and process the output buffers in an implementation
independant manner.

This allows different types of output buffer to be passed
to the decompressors, with the implementation specific
aspects handled at decompression time, but without the
knowledge being held in the decompressor wrapper code.

This will allow the decompressors to handle Squashfs
cache buffers, and page cache pages.

This patch adds the abstraction and an implementation for
the caches.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2013-11-20 03:59:01 +00:00
Phillip Lougher
d208383d64 Squashfs: add multi-threaded decompression using percpu variable
Add a multi-threaded decompression implementation which uses
percpu variables.

Using percpu variables has advantages and disadvantages over
implementations which do not use percpu variables.

Advantages:
  * the nature of percpu variables ensures decompression is
    load-balanced across the multiple cores.
  * simplicity.

Disadvantages: it limits decompression to one thread per core.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2013-11-20 03:58:03 +00:00
Minchan Kim
cd59c2ec5f squashfs: Enhance parallel I/O
Now squashfs have used for only one stream buffer for decompression
so it hurts parallel read performance so this patch supports
multiple decompressor to enhance performance parallel I/O.

Four 1G file dd read on KVM machine which has 2 CPU and 4G memory.

dd if=test/test1.dat of=/dev/null &
dd if=test/test2.dat of=/dev/null &
dd if=test/test3.dat of=/dev/null &
dd if=test/test4.dat of=/dev/null &

old : 1m39s -> new : 9s

* From v1
  * Change comp_strm with decomp_strm - Phillip
  * Change/add comments - Phillip

Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2013-11-20 03:35:18 +00:00
Phillip Lougher
9508c6b90b Squashfs: Refactor decompressor interface and code
The decompressor interface and code was written from
the point of view of single-threaded operation.  In doing
so it mixed a lot of single-threaded implementation specific
aspects into the decompressor code and elsewhere which makes it
difficult to seamlessly support multiple different decompressor
implementations.

This patch does the following:

1.  It removes compressor_options parsing from the decompressor
    init() function.  This allows the decompressor init() function
    to be dynamically called to instantiate multiple decompressors,
    without the compressor options needing to be read and parsed each
    time.

2.  It moves threading and all sleeping operations out of the
    decompressors.  In doing so, it makes the decompressors
    non-blocking wrappers which only deal with interfacing with
    the decompressor implementation.

3. It splits decompressor.[ch] into decompressor generic functions
   in decompressor.[ch], and moves the single threaded
   decompressor implementation into decompressor_single.c.

The result of this patch is Squashfs should now be able to
support multiple decompressors by adding new decompressor_xxx.c
files with specialised implementations of the functions in
decompressor_single.c

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2013-11-20 03:35:18 +00:00
Linus Torvalds
1ee2dcc224 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Mostly these are fixes for fallout due to merge window changes, as
  well as cures for problems that have been with us for a much longer
  period of time"

 1) Johannes Berg noticed two major deficiencies in our genetlink
    registration.  Some genetlink protocols we passing in constant
    counts for their ops array rather than something like
    ARRAY_SIZE(ops) or similar.  Also, some genetlink protocols were
    using fixed IDs for their multicast groups.

    We have to retain these fixed IDs to keep existing userland tools
    working, but reserve them so that other multicast groups used by
    other protocols can not possibly conflict.

    In dealing with these two problems, we actually now use less state
    management for genetlink operations and multicast groups.

 2) When configuring interface hardware timestamping, fix several
    drivers that simply do not validate that the hwtstamp_config value
    is one the driver actually supports.  From Ben Hutchings.

 3) Invalid memory references in mwifiex driver, from Amitkumar Karwar.

 4) In dev_forward_skb(), set the skb->protocol in the right order
    relative to skb_scrub_packet().  From Alexei Starovoitov.

 5) Bridge erroneously fails to use the proper wrapper functions to make
    calls to netdev_ops->ndo_vlan_rx_{add,kill}_vid.  Fix from Toshiaki
    Makita.

 6) When detaching a bridge port, make sure to flush all VLAN IDs to
    prevent them from leaking, also from Toshiaki Makita.

 7) Put in a compromise for TCP Small Queues so that deep queued devices
    that delay TX reclaim non-trivially don't have such a performance
    decrease.  One particularly problematic area is 802.11 AMPDU in
    wireless.  From Eric Dumazet.

 8) Fix crashes in tcp_fastopen_cache_get(), we can see NULL socket dsts
    here.  Fix from Eric Dumzaet, reported by Dave Jones.

 9) Fix use after free in ipv6 SIT driver, from Willem de Bruijn.

10) When computing mergeable buffer sizes, virtio-net fails to take the
    virtio-net header into account.  From Michael Dalton.

11) Fix seqlock deadlock in ip4_datagram_connect() wrt.  statistic
    bumping, this one has been with us for a while.  From Eric Dumazet.

12) Fix NULL deref in the new TIPC fragmentation handling, from Erik
    Hugne.

13) 6lowpan bit used for traffic classification was wrong, from Jukka
    Rissanen.

14) macvlan has the same issue as normal vlans did wrt.  propagating LRO
    disabling down to the real device, fix it the same way.  From Michal
    Kubecek.

15) CPSW driver needs to soft reset all slaves during suspend, from
    Daniel Mack.

16) Fix small frame pacing in FQ packet scheduler, from Eric Dumazet.

17) The xen-netfront RX buffer refill timer isn't properly scheduled on
    partial RX allocation success, from Ma JieYue.

18) When ipv6 ping protocol support was added, the AF_INET6 protocol
    initialization cleanup path on failure was borked a little.  Fix
    from Vlad Yasevich.

19) If a socket disconnects during a read/recvmsg/recvfrom/etc that
    blocks we can do the wrong thing with the msg_name we write back to
    userspace.  From Hannes Frederic Sowa.  There is another fix in the
    works from Hannes which will prevent future problems of this nature.

20) Fix route leak in VTI tunnel transmit, from Fan Du.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (106 commits)
  genetlink: make multicast groups const, prevent abuse
  genetlink: pass family to functions using groups
  genetlink: add and use genl_set_err()
  genetlink: remove family pointer from genl_multicast_group
  genetlink: remove genl_unregister_mc_group()
  hsr: don't call genl_unregister_mc_group()
  quota/genetlink: use proper genetlink multicast APIs
  drop_monitor/genetlink: use proper genetlink multicast APIs
  genetlink: only pass array to genl_register_family_with_ops()
  tcp: don't update snd_nxt, when a socket is switched from repair mode
  atm: idt77252: fix dev refcnt leak
  xfrm: Release dst if this dst is improper for vti tunnel
  netlink: fix documentation typo in netlink_set_err()
  be2net: Delete secondary unicast MAC addresses during be_close
  be2net: Fix unconditional enabling of Rx interface options
  net, virtio_net: replace the magic value
  ping: prevent NULL pointer dereference on write to msg_name
  bnx2x: Prevent "timeout waiting for state X"
  bnx2x: prevent CFC attention
  bnx2x: Prevent panic during DMAE timeout
  ...
2013-11-19 15:50:47 -08:00
J. Bruce Fields
365da4adeb nfsd4: fix xdr decoding of large non-write compounds
This fixes a regression from 247500820e
"nfsd4: fix decoding of compounds across page boundaries".  The previous
code was correct: argp->pagelist is initialized in
nfs4svc_deocde_compoundargs to rqstp->rq_arg.pages, and is therefore a
pointer to the page *after* the page we are currently decoding.

The reason that patch nevertheless fixed a problem with decoding
compounds containing write was a bug in the write decoding introduced by
5a80a54d21 "nfsd4: reorganize write
decoding", after which write decoding no longer adhered to the rule that
argp->pagelist point to the next page.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-11-19 18:06:54 -05:00
Sasha Levin
ddb8c45ba1 aio: nullify aio->ring_pages after freeing it
After freeing ring_pages we leave it as is causing a dangling pointer. This
has already caused an issue so to help catching any issues in the future
NULL it out.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
2013-11-19 17:40:48 -05:00
Sasha Levin
d558023207 aio: prevent double free in ioctx_alloc
ioctx_alloc() calls aio_setup_ring() to allocate a ring. If aio_setup_ring()
fails to do so it would call aio_free_ring() before returning, but
ioctx_alloc() would call aio_free_ring() again causing a double free of
the ring.

This is easily reproducible from userspace.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
2013-11-19 17:40:48 -05:00
Johannes Berg
2a94fe48f3 genetlink: make multicast groups const, prevent abuse
Register generic netlink multicast groups as an array with
the family and give them contiguous group IDs. Then instead
of passing the global group ID to the various functions that
send messages, pass the ID relative to the family - for most
families that's just 0 because the only have one group.

This avoids the list_head and ID in each group, adding a new
field for the mcast group ID offset to the family.

At the same time, this allows us to prevent abusing groups
again like the quota and dropmon code did, since we can now
check that a family only uses a group it owns.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:06 -05:00
Johannes Berg
68eb55031d genetlink: pass family to functions using groups
This doesn't really change anything, but prepares for the
next patch that will change the APIs to pass the group ID
within the family, rather than the global group ID.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:06 -05:00
Johannes Berg
2ecf7536b2 quota/genetlink: use proper genetlink multicast APIs
The quota code is abusing the genetlink API and is using
its family ID as the multicast group ID, which is invalid
and may belong to somebody else (and likely will.)

Make the quota code use the correct API, but since this
is already used as-is by userspace, reserve a family ID
for this code and also reserve that group ID to not break
userspace assumptions.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:05 -05:00
Johannes Berg
c53ed74236 genetlink: only pass array to genl_register_family_with_ops()
As suggested by David Miller, make genl_register_family_with_ops()
a macro and pass only the array, evaluating ARRAY_SIZE() in the
macro, this is a little safer.

The openvswitch has some indirection, assing ops/n_ops directly in
that code. This might ultimately just assign the pointers in the
family initializations, saving the struct genl_family_and_ops and
code (once mcast groups are handled differently.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:05 -05:00
Al Viro
801a76050b seq_file: always clear m->count when we free m->buf
Once we'd freed m->buf, m->count should become zero - we have no valid
contents reachable via m->buf.

Reported-by: Charley (Hao Chuan) Chu <charley.chu@broadcom.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-18 19:07:53 -08:00
Akinobu Mita
34f2fd8dfe bio: fix argument of __bio_add_page() for max_sectors > 0xffff
The data type of max_sectors and max_hw_sectors in queue settings are
unsigned int.  But these values are passed to __bio_add_page() as an
argument whose data type is unsigned short.  In the worst case such as
max_sectors is 0x10000, bio_add_page() can't add a page and IOs can't
proceed.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-11-18 12:31:27 -07:00
Christoph Hellwig
987da47910 nfsd: make sure to balance get/put_write_access
Use a straight goto error label style in nfsd_setattr to make sure
we always do the put_write_access call after we got it earlier.

Note that the we have been failing to do that in the case
nfsd_break_lease() returns an error, a bug introduced into 2.6.38 with
6a76bebefe "nfsd4: break lease on nfsd
setattr".

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-11-18 12:06:48 -05:00
Christoph Hellwig
818e5a22e9 nfsd: split up nfsd_setattr
Split out two helpers to make the code more readable and easier to verify
for correctness.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-11-18 12:06:47 -05:00
Dave Chinner
2fe8c1c08b xfs: open code inc_inode_iversion when logging an inode
Michael L Semon reported that generic/069 runtime increased on v5
superblocks by 100% compared to v4 superblocks. his perf-based
analysis pointed directly at the timestamp updates being done by the
write path in this workload. The append writers are doing 4-byte
writes, so there are lots of timestamp updates occurring.

The thing is, they aren't being triggered by timestamp changes -
they are being triggered by the inode change counter needing to be
updated. That is, every write(2) system call needs to bump the inode
version count, and it does that through the timestamp update
mechanism. Hence for v5 filesystems, test generic/069 is running 3
orders of magnitude more timestmap update transactions on v5
filesystems due to the fact it does a huge number of *4 byte*
write(2) calls.

This isn't a real world scenario we really need to address - anyone
doing such sequential IO should be using fwrite(3), not write(2).
i.e. fwrite(3) buffers the writes in userspace to minimise the
number of write(2) syscalls, and the problem goes away.

However, there is a small change we can make to improve the
situation - removing the expensive lock operation on the change
counter update.  All inode version counter changes in XFS occur
under the ip->i_ilock during a transaction, and therefore we
don't actually need the spin lock that provides exclusive access to
it through inc_inode_iversion().

Hence avoid the lock and just open code the increment ourselves when
logging the inode.

Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-11-18 09:42:08 -06:00