dect
/
linux-2.6
Archived
13
0
Fork 0
Commit Graph

832 Commits

Author SHA1 Message Date
Bart Van Assche d3f70befd9 docs/sysfs: show() methods should use scnprintf().
Since snprintf() may return a value that exceeds its second argument,
show() methods should use scnprintf() instead of snprintf(). This patch
updates the example in the sysfs documentation accordingly.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03 15:10:18 -08:00
Bart Van Assche 5480bcdd60 docs/sysfs: Update directory/kobject documentation.
Some time ago the way how sysfs stores a pointer to a kobject
corresponding to a directory was modified. This patch brings the
documentation again in sync with the implementation.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03 15:10:18 -08:00
Anton Altaparmakov af5eb745ef NTFS: Fix invalid pointer dereference in ntfs_mft_record_alloc().
In ntfs_mft_record_alloc() when mapping the new extent mft record with
map_extent_mft_record() we overwrite @m with the return value and on
error, we then try to use the old @m but that is no longer there as @m
now contains an error code instead so we crash when dereferencing the
error code as if it were a pointer.

The simple fix is to use a temporary variable to store the return value
thus preserving the original @m for later use.  This is a backport from
the commercial Tuxera-NTFS driver and is well tested...

Thanks go to Julia Lawall for pointing this out (whilst I had fixed it
in the commercial driver I had failed to fix it in the Linux kernel).

Signed-off-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-31 12:58:11 +10:00
Christoph Hellwig 2fe17c1075 fallocate should be a file operation
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 02:25:31 -05:00
Linus Torvalds f8206b925f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (23 commits)
  sanitize vfsmount refcounting changes
  fix old umount_tree() breakage
  autofs4: Merge the remaining dentry ops tables
  Unexport do_add_mount() and add in follow_automount(), not ->d_automount()
  Allow d_manage() to be used in RCU-walk mode
  Remove a further kludge from __do_follow_link()
  autofs4: Bump version
  autofs4: Add v4 pseudo direct mount support
  autofs4: Fix wait validation
  autofs4: Clean up autofs4_free_ino()
  autofs4: Clean up dentry operations
  autofs4: Clean up inode operations
  autofs4: Remove unused code
  autofs4: Add d_manage() dentry operation
  autofs4: Add d_automount() dentry operation
  Remove the automount through follow_link() kludge code from pathwalk
  CIFS: Use d_automount() rather than abusing follow_link()
  NFS: Use d_automount() rather than abusing follow_link()
  AFS: Use d_automount() rather than abusing follow_link()
  Add an AT_NO_AUTOMOUNT flag to suppress terminal automount
  ...
2011-01-16 11:31:50 -08:00
David Howells ea5b778a8b Unexport do_add_mount() and add in follow_automount(), not ->d_automount()
Unexport do_add_mount() and make ->d_automount() return the vfsmount to be
added rather than calling do_add_mount() itself.  follow_automount() will then
do the addition.

This slightly complicates things as ->d_automount() normally wants to add the
new vfsmount to an expiration list and start an expiration timer.  The problem
with that is that the vfsmount will be deleted if it has a refcount of 1 and
the timer will not repeat if the expiration list is empty.

To this end, we require the vfsmount to be returned from d_automount() with a
refcount of (at least) 2.  One of these refs will be dropped unconditionally.
In addition, follow_automount() must get a 3rd ref around the call to
do_add_mount() lest it eat a ref and return an error, leaving the mount we
have open to being expired as we would otherwise have only 1 ref on it.

d_automount() should also add the the vfsmount to the expiration list (by
calling mnt_set_expiry()) and start the expiration timer before returning, if
this mechanism is to be used.  The vfsmount will be unlinked from the
expiration list by follow_automount() if do_add_mount() fails.

This patch also fixes the call to do_add_mount() for AFS to propagate the mount
flags from the parent vfsmount.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:48 -05:00
David Howells ab90911ff9 Allow d_manage() to be used in RCU-walk mode
Allow d_manage() to be called from pathwalk when it is in RCU-walk mode as well
as when it is in Ref-walk mode.  This permits __follow_mount_rcu() to call
d_manage() directly.  d_manage() needs a parameter to indicate that it is in
RCU-walk mode as it isn't allowed to sleep if in that mode (but should return
-ECHILD instead).

autofs4_d_manage() can then be set to retain RCU-walk mode if the daemon
accesses it and otherwise request dropping back to ref-walk mode.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:47 -05:00
David Howells cc53ce53c8 Add a dentry op to allow processes to be held during pathwalk transit
Add a dentry op (d_manage) to permit a filesystem to hold a process and make it
sleep when it tries to transit away from one of that filesystem's directories
during a pathwalk.  The operation is keyed off a new dentry flag
(DCACHE_MANAGE_TRANSIT).

The filesystem is allowed to be selective about which processes it holds and
which it permits to continue on or prohibits from transiting from each flagged
directory.  This will allow autofs to hold up client processes whilst letting
its userspace daemon through to maintain the directory or the stuff behind it
or mounted upon it.

The ->d_manage() dentry operation:

	int (*d_manage)(struct path *path, bool mounting_here);

takes a pointer to the directory about to be transited away from and a flag
indicating whether the transit is undertaken by do_add_mount() or
do_move_mount() skipping through a pile of filesystems mounted on a mountpoint.

It should return 0 if successful and to let the process continue on its way;
-EISDIR to prohibit the caller from skipping to overmounted filesystems or
automounting, and to use this directory; or some other error code to return to
the user.

->d_manage() is called with namespace_sem writelocked if mounting_here is true
and no other locks held, so it may sleep.  However, if mounting_here is true,
it may not initiate or wait for a mount or unmount upon the parameter
directory, even if the act is actually performed by userspace.

Within fs/namei.c, follow_managed() is extended to check with d_manage() first
on each managed directory, before transiting away from it or attempting to
automount upon it.

follow_down() is renamed follow_down_one() and should only be used where the
filesystem deliberately intends to avoid management steps (e.g. autofs).

A new follow_down() is added that incorporates the loop done by all other
callers of follow_down() (do_add/move_mount(), autofs and NFSD; whilst AFS, NFS
and CIFS do use it, their use is removed by converting them to use
d_automount()).  The new follow_down() calls d_manage() as appropriate.  It
also takes an extra parameter to indicate if it is being called from mount code
(with namespace_sem writelocked) which it passes to d_manage().  follow_down()
ignores automount points so that it can be used to mount on them.

__follow_mount_rcu() is made to abort rcu-walk mode if it hits a directory with
DCACHE_MANAGE_TRANSIT set on the basis that we're probably going to have to
sleep.  It would be possible to enter d_manage() in rcu-walk mode too, and have
that determine whether to abort or not itself.  That would allow the autofs
daemon to continue on in rcu-walk mode.

Note that DCACHE_MANAGE_TRANSIT on a directory should be cleared when it isn't
required as every tranist from that directory will cause d_manage() to be
invoked.  It can always be set again when necessary.

==========================
WHAT THIS MEANS FOR AUTOFS
==========================

Autofs currently uses the lookup() inode op and the d_revalidate() dentry op to
trigger the automounting of indirect mounts, and both of these can be called
with i_mutex held.

autofs knows that the i_mutex will be held by the caller in lookup(), and so
can drop it before invoking the daemon - but this isn't so for d_revalidate(),
since the lock is only held on _some_ of the code paths that call it.  This
means that autofs can't risk dropping i_mutex from its d_revalidate() function
before it calls the daemon.

The bug could manifest itself as, for example, a process that's trying to
validate an automount dentry that gets made to wait because that dentry is
expired and needs cleaning up:

	mkdir         S ffffffff8014e05a     0 32580  24956
	Call Trace:
	 [<ffffffff885371fd>] :autofs4:autofs4_wait+0x674/0x897
	 [<ffffffff80127f7d>] avc_has_perm+0x46/0x58
	 [<ffffffff8009fdcf>] autoremove_wake_function+0x0/0x2e
	 [<ffffffff88537be6>] :autofs4:autofs4_expire_wait+0x41/0x6b
	 [<ffffffff88535cfc>] :autofs4:autofs4_revalidate+0x91/0x149
	 [<ffffffff80036d96>] __lookup_hash+0xa0/0x12f
	 [<ffffffff80057a2f>] lookup_create+0x46/0x80
	 [<ffffffff800e6e31>] sys_mkdirat+0x56/0xe4

versus the automount daemon which wants to remove that dentry, but can't
because the normal process is holding the i_mutex lock:

	automount     D ffffffff8014e05a     0 32581      1              32561
	Call Trace:
	 [<ffffffff80063c3f>] __mutex_lock_slowpath+0x60/0x9b
	 [<ffffffff8000ccf1>] do_path_lookup+0x2ca/0x2f1
	 [<ffffffff80063c89>] .text.lock.mutex+0xf/0x14
	 [<ffffffff800e6d55>] do_rmdir+0x77/0xde
	 [<ffffffff8005d229>] tracesys+0x71/0xe0
	 [<ffffffff8005d28d>] tracesys+0xd5/0xe0

which means that the system is deadlocked.

This patch allows autofs to hold up normal processes whilst the daemon goes
ahead and does things to the dentry tree behind the automouter point without
risking a deadlock as almost no locks are held in d_manage() and none in
d_automount().

Signed-off-by: David Howells <dhowells@redhat.com>
Was-Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:31 -05:00
David Howells 9875cf8064 Add a dentry op to handle automounting rather than abusing follow_link()
Add a dentry op (d_automount) to handle automounting directories rather than
abusing the follow_link() inode operation.  The operation is keyed off a new
dentry flag (DCACHE_NEED_AUTOMOUNT).

This also makes it easier to add an AT_ flag to suppress terminal segment
automount during pathwalk and removes the need for the kludge code in the
pathwalk algorithm to handle directories with follow_link() semantics.

The ->d_automount() dentry operation:

	struct vfsmount *(*d_automount)(struct path *mountpoint);

takes a pointer to the directory to be mounted upon, which is expected to
provide sufficient data to determine what should be mounted.  If successful, it
should return the vfsmount struct it creates (which it should also have added
to the namespace using do_add_mount() or similar).  If there's a collision with
another automount attempt, NULL should be returned.  If the directory specified
by the parameter should be used directly rather than being mounted upon,
-EISDIR should be returned.  In any other case, an error code should be
returned.

The ->d_automount() operation is called with no locks held and may sleep.  At
this point the pathwalk algorithm will be in ref-walk mode.

Within fs/namei.c itself, a new pathwalk subroutine (follow_automount()) is
added to handle mountpoints.  It will return -EREMOTE if the automount flag was
set, but no d_automount() op was supplied, -ELOOP if we've encountered too many
symlinks or mountpoints, -EISDIR if the walk point should be used without
mounting and 0 if successful.  The path will be updated to point to the mounted
filesystem if a successful automount took place.

__follow_mount() is replaced by follow_managed() which is more generic
(especially with the patch that adds ->d_manage()).  This handles transits from
directories during pathwalk, including automounting and skipping over
mountpoints (and holding processes with the next patch).

__follow_mount_rcu() will jump out of RCU-walk mode if it encounters an
automount point with nothing mounted on it.

follow_dotdot*() does not handle automounts as you don't want to trigger them
whilst following "..".

I've also extracted the mount/don't-mount logic from autofs4 and included it
here.  It makes the mount go ahead anyway if someone calls open() or creat(),
tries to traverse the directory, tries to chdir/chroot/etc. into the directory,
or sticks a '/' on the end of the pathname.  If they do a stat(), however,
they'll only trigger the automount if they didn't also say O_NOFOLLOW.

I've also added an inode flag (S_AUTOMOUNT) so that filesystems can mark their
inodes as automount points.  This flag is automatically propagated to the
dentry as DCACHE_NEED_AUTOMOUNT by __d_instantiate().  This saves NFS and could
save AFS a private flag bit apiece, but is not strictly necessary.  It would be
preferable to do the propagation in d_set_d_op(), but that doesn't normally
have access to the inode.

[AV: fixed breakage in case if __follow_mount_rcu() fails and nameidata_drop_rcu()
succeeds in RCU case of do_lookup(); we need to fall through to non-RCU case after
that, rather than just returning with ungrabbed *path]

Signed-off-by: David Howells <dhowells@redhat.com>
Was-Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:05:03 -05:00
Linus Torvalds 18bce371ae Merge branch 'for-2.6.38' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits)
  nfsd4: fix callback restarting
  nfsd: break lease on unlink, link, and rename
  nfsd4: break lease on nfsd setattr
  nfsd: don't support msnfs export option
  nfsd4: initialize cb_per_client
  nfsd4: allow restarting callbacks
  nfsd4: simplify nfsd4_cb_prepare
  nfsd4: give out delegations more quickly in 4.1 case
  nfsd4: add helper function to run callbacks
  nfsd4: make sure sequence flags are set after destroy_session
  nfsd4: re-probe callback on connection loss
  nfsd4: set sequence flag when backchannel is down
  nfsd4: keep finer-grained callback status
  rpc: allow xprt_class->setup to return a preexisting xprt
  rpc: keep backchannel xprt as long as server connection
  rpc: move sk_bc_xprt to svc_xprt
  nfsd4: allow backchannel recovery
  nfsd4: support BIND_CONN_TO_SESSION
  nfsd4: modify session list under cl_lock
  Documentation: fl_mylease no longer exists
  ...

Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work.  The
vfs-scale work touched some msnfs cases, and this merge removes support
for that entirely, so the conflict was trivial to resolve.
2011-01-14 13:17:26 -08:00
Linus Torvalds db9effe99a Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin
* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin:
  fs: fix do_last error case when need_reval_dot
  nfs: add missing rcu-walk check
  fs: hlist UP debug fixup
  fs: fix dropping of rcu-walk from force_reval_path
  fs: force_reval_path drop rcu-walk before d_invalidate
  fs: small rcu-walk documentation fixes

Fixed up trivial conflicts in Documentation/filesystems/porting
2011-01-13 20:14:13 -08:00
Nick Piggin a82416da83 fs: small rcu-walk documentation fixes
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-14 02:26:53 +00:00
Mandeep Singh Baines dabb16f639 oom: allow a non-CAP_SYS_RESOURCE proces to oom_score_adj down
We'd like to be able to oom_score_adj a process up/down as it
enters/leaves the foreground.  Currently, it is not possible to oom_adj
down without CAP_SYS_RESOURCE.  This patch allows a task to decrease its
oom_score_adj back to the value that a CAP_SYS_RESOURCE thread set it to
or its inherited value at fork.  Assuming the thread that has forked it
has oom_score_adj of 0, each process could decrease it back from 0 upon
activation unless a CAP_SYS_RESOURCE thread elevated it to something
higher.

Alternative considered:

* a setuid binary
* a daemon with CAP_SYS_RESOURCE

Since you don't wan't all processes to be able to reduce their oom_adj, a
setuid or daemon implementation would be complex.  The alternatives also
have much higher overhead.

This patch updated from original patch based on feedback from David
Rientjes.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:35 -08:00
Nikanth Karthikesan 2d90508f63 mm: smaps: export mlock information
Currently there is no way to find whether a process has locked its pages
in memory or not.  And which of the memory regions are locked in memory.

Add a new field "Locked" to export this information via the smaps file.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:33 -08:00
Linus Torvalds b2034d474b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
  fs: add documentation on fallocate hole punching
  Gfs2: fail if we try to use hole punch
  Btrfs: fail if we try to use hole punch
  Ext4: fail if we try to use hole punch
  Ocfs2: handle hole punching via fallocate properly
  XFS: handle hole punching via fallocate properly
  fs: add hole punching to fallocate
  vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
  fix signedness mess in rw_verify_area() on 64bit architectures
  fs: fix kernel-doc for dcache::prepend_path
  fs: fix kernel-doc for dcache::d_validate
  sanitize ecryptfs ->mount()
  switch afs
  move internal-only parts of ncpfs headers to fs/ncpfs
  switch ncpfs
  switch 9p
  pass default dentry_operations to mount_pseudo()
  switch hostfs
  switch affs
  switch configfs
  ...
2011-01-13 10:27:28 -08:00
Josef Bacik 924241575a fs: add documentation on fallocate hole punching
This patch simply adds documentation on how to handle the hole punching mode of
fallocate for any filesystem wishing to use it.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:19:03 -05:00
Anton Altaparmakov 2818ef50c4 NTFS: writev() fix and maintenance/contact details update
Fix writev() to not keep writing the first segment over and over again
instead of moving onto subsequent segments and update the NTFS entry in
MAINTAINERS to reflect that Tuxera Inc. now supports the NTFS driver.

Signed-off-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-12 08:35:53 -08:00
J. Bruce Fields ec26fba40f Documentation: fl_mylease no longer exists
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-11 15:04:09 -05:00
Linus Torvalds 56b85f32d5 Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (36 commits)
  serial: apbuart: Fixup apbuart_console_init()
  TTY: Add tty ioctl to figure device node of the system console.
  tty: add 'active' sysfs attribute to tty0 and console device
  drivers: serial: apbuart: Handle OF failures gracefully
  Serial: Avoid unbalanced IRQ wake disable during resume
  tty: fix typos/errors in tty_driver.h comments
  pch_uart : fix warnings for 64bit compile
  8250: fix uninitialized FIFOs
  ip2: fix compiler warning on ip2main_pci_tbl
  specialix: fix compiler warning on specialix_pci_tbl
  rocket: fix compiler warning on rocket_pci_ids
  8250: add a UPIO_DWAPB32 for 32 bit accesses
  8250: use container_of() instead of casting
  serial: omap-serial: Add support for kernel debugger
  serial: fix pch_uart kconfig & build
  drivers: char: hvc: add arm JTAG DCC console support
  RS485 documentation: add 16C950 UART description
  serial: ifx6x60: fix memory leak
  serial: ifx6x60: free IRQ on error
  Serial: EG20T: add PCH_UART driver
  ...

Fixed up conflicts in drivers/serial/apbuart.c with evil merge that
makes the code look fairly sane (unlike either side).
2011-01-07 14:39:20 -08:00
Nick Piggin b74c79e993 fs: provide rcu-walk aware permission i_ops
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin 34286d6662 fs: rcu-walk aware d_revalidate method
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin 31e6b01f41 fs: rcu-walk for path lookup
Perform common cases of path lookups without any stores or locking in the
ancestor dentry elements. This is called rcu-walk, as opposed to the current
algorithm which is a refcount based walk, or ref-walk.

This results in far fewer atomic operations on every path element,
significantly improving path lookup performance. It also avoids cacheline
bouncing on common dentries, significantly improving scalability.

The overall design is like this:
* LOOKUP_RCU is set in nd->flags, which distinguishes rcu-walk from ref-walk.
* Take the RCU lock for the entire path walk, starting with the acquiring
  of the starting path (eg. root/cwd/fd-path). So now dentry refcounts are
  not required for dentry persistence.
* synchronize_rcu is called when unregistering a filesystem, so we can
  access d_ops and i_ops during rcu-walk.
* Similarly take the vfsmount lock for the entire path walk. So now mnt
  refcounts are not required for persistence. Also we are free to perform mount
  lookups, and to assume dentry mount points and mount roots are stable up and
  down the path.
* Have a per-dentry seqlock to protect the dentry name, parent, and inode,
  so we can load this tuple atomically, and also check whether any of its
  members have changed.
* Dentry lookups (based on parent, candidate string tuple) recheck the parent
  sequence after the child is found in case anything changed in the parent
  during the path walk.
* inode is also RCU protected so we can load d_inode and use the inode for
  limited things.
* i_mode, i_uid, i_gid can be tested for exec permissions during path walk.
* i_op can be loaded.

When we reach the destination dentry, we lock it, recheck lookup sequence,
and increment its refcount and mountpoint refcount. RCU and vfsmount locks
are dropped. This is termed "dropping rcu-walk". If the dentry refcount does
not match, we can not drop rcu-walk gracefully at the current point in the
lokup, so instead return -ECHILD (for want of a better errno). This signals the
path walking code to re-do the entire lookup with a ref-walk.

Aside from the final dentry, there are other situations that may be encounted
where we cannot continue rcu-walk. In that case, we drop rcu-walk (ie. take
a reference on the last good dentry) and continue with a ref-walk. Again, if
we can drop rcu-walk gracefully, we return -ECHILD and do the whole lookup
using ref-walk. But it is very important that we can continue with ref-walk
for most cases, particularly to avoid the overhead of double lookups, and to
gain the scalability advantages on common path elements (like cwd and root).

The cases where rcu-walk cannot continue are:
* NULL dentry (ie. any uncached path element)
* parent with d_inode->i_op->permission or ACLs
* dentries with d_revalidate
* Following links

In future patches, permission checks and d_revalidate become rcu-walk aware. It
may be possible eventually to make following links rcu-walk aware.

Uncached path elements will always require dropping to ref-walk mode, at the
very least because i_mutex needs to be grabbed, and objects allocated.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:27 +11:00
Nick Piggin fa0d7e3de6 fs: icache RCU free inodes
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:26 +11:00
Nick Piggin b5c84bf6f6 fs: dcache remove dcache_lock
dcache_lock no longer protects anything. remove it.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:23 +11:00
Nick Piggin b1e6a015a5 fs: change d_hash for rcu-walk
Change d_hash so it may be called from lock-free RCU lookups. See similar
patch for d_compare for details.

For in-tree filesystems, this is just a mechanical change.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:20 +11:00
Nick Piggin 621e155a35 fs: change d_compare for rcu-walk
Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.

For in-tree filesystems, this is just a mechanical change.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:19 +11:00
Nick Piggin fe15ce446b fs: change d_delete semantics
Change d_delete from a dentry deletion notification to a dentry caching
advise, more like ->drop_inode. Require it to be constant and idempotent,
and not take d_lock. This is how all existing filesystems use the callback
anyway.

This makes fine grained dentry locking of dput and dentry lru scanning
much simpler.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:18 +11:00
Christoph Hellwig 8a87694ed1 remove trim_fs method from Documentation/filesystems/Locking
The ->trim_fs has been removed meanwhile, so remove it from the documentation
as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-04 11:01:09 -08:00
Christoph Hellwig b83be6f20a update Documentation/filesystems/Locking
Mostly inspired by all the recent BKL removal changes, but a lot of older
updates also weren't properly recorded.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-30 10:00:50 -08:00
Linus Torvalds 38971ce2fa Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: Fix panic after nfs_umount()
  nfs: remove extraneous and problematic calls to nfs_clear_request
  nfs: kernel should return EPROTONOSUPPORT when not support NFSv4
  NFS: Fix fcntl F_GETLK not reporting some conflicts
  nfs: Discard ACL cache on mode update
  NFS: Readdir cleanups
  NFS: nfs_readdir_search_for_cookie() don't mark as eof if cookie not found
  NFS: Fix a memory leak in nfs_readdir
  Call the filesystem back whenever a page is removed from the page cache
  NFS: Ensure we use the correct cookie in nfs_readdir_xdr_filler
2010-12-14 08:51:12 -08:00
Andrew Morton 4fe65cab84 Documentation/filesystems/vfs.txt: fix ->repeasepage() description
->releasepage() does not remove the page from the mapping.

Acked-by: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-02 14:51:15 -08:00
Linus Torvalds 6072d13c42 Call the filesystem back whenever a page is removed from the page cache
NFS needs to be able to release objects that are stored in the page
cache once the page itself is no longer visible from the page cache.

This patch adds a callback to the address space operations that allows
filesystems to perform page cleanups once the page has been removed
from the page cache.

Original patch by: Linus Torvalds <torvalds@linux-foundation.org>
[trondmy: cover the cases of invalidate_inode_pages2() and
          truncate_inode_pages()]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-02 09:55:21 -05:00
Dan Carpenter 09c9feb946 Documentation: make configfs example code simpler, clearer
If "p" is NULL then it will cause an oops when we pass it to
simple_strtoul().  In this case "p" can not be NULL so I removed the
check.  I also changed the check a little to make it more explicit that
we are testing whether p points to the NUL char.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18 15:00:46 -08:00
Jiri Slaby 23308ba54d console: add /proc/consoles
It allows users to see what consoles are currently known to the system
and with what flags.

It is based on Werner's patch, the part about traversing fds was
removed, the code was moved to kernel/printk.c, where consoles are
handled and it makes more sense to me.

Signed-off-by: Jiri Slaby <jslaby@suse.cz> [cleanups]
Signed-off-by: "Dr. Werner Fink" <werner@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-16 12:50:17 -08:00
Christoph Hellwig 5d0af85cd0 xfs: remove experimental tag from the delaylog option
We promised to do this for 2.6.37, and the code looks stable enough to
keep that promise.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-11-10 12:00:47 -06:00
Christoph Hellwig bb8430a2c8 locks: remove fl_copy_lock lock_manager operation
This one was only used for a nasty hack in nfsd, which has recently
been removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-31 06:35:15 -07:00
Linus Torvalds f063a0c0c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (841 commits)
  Staging: brcm80211: fix usage of roundup in structures
  Staging: bcm: fix up network device reference counting
  Staging: keucr: fix up US_ macro change
  staging: brcm80211: brcmfmac: Removed codeversion from firmware filenames.
  staging: brcm80211: Remove unnecessary header files.
  staging: brcm80211: Remove unnecessary includes from bcmutils.c
  staging: brcm80211: Removed unnecessary pktsetprio() function.
  Staging: brcm80211: remove typedefs.h
  Staging: brcm80211: remove uintptr typedef usage
  Staging: hv: remove struct vmbus_channel_interface
  Staging: hv: remove Open from struct vmbus_channel_interface
  Staging: hv: storvsc: call vmbus_open directly
  Staging: hv: netvsc: call vmbus_open directly
  Staging: hv: channel: export vmbus_open to modules
  Staging: hv: remove Close from struct vmbus_channel_interface
  Staging: hv: netvsc: call vmbus_close directly
  Staging: hv: storvsc: call vmbus_close directly
  Staging: hv: channel: export vmbus_close to modules
  Staging: hv: remove SendPacket from struct vmbus_channel_interface
  Staging: hv: storvsc: call vmbus_sendpacket directly
  ...

Fix up conflicts in
	drivers/staging/cx25821/cx25821-audio-upstream.c
	drivers/staging/cx25821/cx25821-audio.h
due to warring whitespace cleanups (neither of which were all that great)
2010-10-28 12:13:00 -07:00
Greg Kroah-Hartman e4c5bf8e3d Merge 'staging-next' to Linus's tree
This merges the staging-next tree to Linus's tree and resolves
some conflicts that were present due to changes in other trees that were
affected by files here.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-28 09:44:56 -07:00
Aneesh Kumar K.V 76381a42e4 fs/9p: Add access = client option to opt in acl evaluation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-10-28 09:08:46 -05:00
Theodore Ts'o a107e5a3a4 Merge branch 'next' into upstream-merge
Conflicts:
	fs/ext4/inode.c
	fs/ext4/mballoc.c
	include/trace/events/ext4.h
2010-10-27 23:44:47 -04:00
Lukas Czerner bfff68738f ext4: add support for lazy inode table initialization
When the lazy_itable_init extended option is passed to mke2fs, it
considerably speeds up filesystem creation because inode tables are
not zeroed out.  The fact that parts of the inode table are
uninitialized is not a problem so long as the block group descriptors,
which contain information regarding how much of the inode table has
been initialized, has not been corrupted However, if the block group
checksums are not valid, e2fsck must scan the entire inode table, and
the the old, uninitialized data could potentially cause e2fsck to
report false problems.

Hence, it is important for the inode tables to be initialized as soon
as possble.  This commit adds this feature so that mke2fs can safely
use the lazy inode table initialization feature to speed up formatting
file systems.

This is done via a new new kernel thread called ext4lazyinit, which is
created on demand and destroyed, when it is no longer needed.  There
is only one thread for all ext4 filesystems in the system. When the
first filesystem with inititable mount option is mounted, ext4lazyinit
thread is created, then the filesystem can register its request in the
request list.

This thread then walks through the list of requests picking up
scheduled requests and invoking ext4_init_inode_table(). Next schedule
time for the request is computed by multiplying the time it took to
zero out last inode table with wait multiplier, which can be set with
the (init_itable=n) mount option (default is 10).  We are doing
this so we do not take the whole I/O bandwidth. When the thread is no
longer necessary (request list is empty) it frees the appropriate
structures and exits (and can be created later later by another
filesystem).

We do not disturb regular inode allocations in any way, it just do not
care whether the inode table is, or is not zeroed. But when zeroing, we
have to skip used inodes, obviously. Also we should prevent new inode
allocations from the group, while zeroing is on the way. For that we
take write alloc_sem lock in ext4_init_inode_table() and read alloc_sem
in the ext4_claim_inode, so when we are unlucky and allocator hits the
group which is currently being zeroed, it just has to wait.

This can be suppresed using the mount option no_init_itable.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 21:30:05 -04:00
Nikanth Karthikesan 03f890f8c2 /proc/pid/pagemap: document in Documentation/filesystems/proc.txt
Document /proc/pid/pagemap in Documentation/filesystems/proc.txt

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Cc: Richard Guenther <rguenther@suse.de>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:13 -07:00
Nikanth Karthikesan b40d4f84be /proc/pid/smaps: export amount of anonymous memory in a mapping
Export the number of anonymous pages in a mapping via smaps.

Even the private pages in a mapping backed by a file, would be marked as
anonymous, when they are modified. Export this information to user-space via
smaps.

Exporting this count will help gdb to make a better decision on which
areas need to be dumped in its coredump; and should be useful to others
studying the memory usage of a process.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:13 -07:00
Linus Torvalds 426e1f5cec Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
  split invalidate_inodes()
  fs: skip I_FREEING inodes in writeback_sb_inodes
  fs: fold invalidate_list into invalidate_inodes
  fs: do not drop inode_lock in dispose_list
  fs: inode split IO and LRU lists
  fs: switch bdev inode bdi's correctly
  fs: fix buffer invalidation in invalidate_list
  fsnotify: use dget_parent
  smbfs: use dget_parent
  exportfs: use dget_parent
  fs: use RCU read side protection in d_validate
  fs: clean up dentry lru modification
  fs: split __shrink_dcache_sb
  fs: improve DCACHE_REFERENCED usage
  fs: use percpu counter for nr_dentry and nr_dentry_unused
  fs: simplify __d_free
  fs: take dcache_lock inside __d_path
  fs: do not assign default i_ino in new_inode
  fs: introduce a per-cpu last_ino allocator
  new helper: ihold()
  ...
2010-10-26 17:58:44 -07:00
Linus Torvalds 18a043f941 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: rename nfs.upcall -> nfs.idmap
  NFS: Fix a compile issue in nfs_root
2010-10-26 17:24:28 -07:00
Matt Mackall 0f4d208f19 Documentation/filesystems/proc.txt: improve smaps field documentation
Signed-off-by: Matt Mackall <mpm@selenic.com>
Cc: Nikanth Karthikesan <knikanth@suse.de>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:05 -07:00
Bryan Schumaker eb1c86b8b5 NFS: rename nfs.upcall -> nfs.idmap
This patch renames the idmapper upcall program from nfs.upcall to nfs.idmap in
the NFS documentation.  This is because the program has been renamed in the
nfs-utils source.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-26 13:57:10 -04:00
Linus Torvalds a4dd8dce14 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  net/sunrpc: Use static const char arrays
  nfs4: fix channel attribute sanity-checks
  NFSv4.1: Use more sensible names for 'initialize_mountpoint'
  NFSv4.1: pnfs: filelayout: add driver's LAYOUTGET and GETDEVICEINFO infrastructure
  NFSv4.1: pnfs: add LAYOUTGET and GETDEVICEINFO infrastructure
  NFS: client needs to maintain list of inodes with active layouts
  NFS: create and destroy inode's layout cache
  NFSv4.1: pnfs: filelayout: introduce minimal file layout driver
  NFSv4.1: pnfs: full mount/umount infrastructure
  NFS: set layout driver
  NFS: ask for layouttypes during v4 fsinfo call
  NFS: change stateid to be a union
  NFSv4.1: pnfsd, pnfs: protocol level pnfs constants
  SUNRPC: define xdr_decode_opaque_fixed
  NFSD: remove duplicate NFS4_STATEID_SIZE
2010-10-26 09:52:09 -07:00
Christoph Hellwig e1455d1bdc update block_device_operations documentation
Updated Documentation/filesystems/Locking to match the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2010-10-25 21:18:22 -04:00
Valerie Aurora d9d1dc802f Documentation: Fix trivial typo in filesystems/sharedsubtree.txt
Documentation: Fix trivial typo in filesystems/sharedsubtree.txt

This typo is easy to ignore unless you have spent a great deal of time
thinking about how to eliminate duplicate dentries in unions.

Signed-off-by: Valerie Aurora <vaurora@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:18:21 -04:00
Linus Torvalds 74eb94b218 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
  SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
  nfs: fix unchecked value
  Ask for time_delta during fsinfo probe
  Revalidate caches on lock
  SUNRPC: After calling xprt_release(), we must restart from call_reserve
  NFSv4: Fix up the 'dircount' hint in encode_readdir
  NFSv4: Clean up nfs4_decode_dirent
  NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
  NFSv4: Fix a regression in decode_getfattr
  NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
  NFS: Ensure we check all allocation return values in new readdir code
  NFS: Readdir plus in v4
  NFS: introduce generic decode_getattr function
  NFS: check xdr_decode for errors
  NFS: nfs_readdir_filler catch all errors
  NFS: readdir with vmapped pages
  NFS: remove page size checking code
  NFS: decode_dirent should use an xdr_stream
  SUNRPC: Add a helper function xdr_inline_peek
  NFS: remove readdir plus limit
  ...
2010-10-25 13:48:29 -07:00
Fred Isaman 02c35fca7c NFSv4.1: pnfs: full mount/umount infrastructure
Allow a module implementing a layout type to register, and
have its mount/umount routines called for filesystems that
the server declares support it.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-24 18:07:10 -04:00
Linus Torvalds 6c2754c28f Revert "tty: Add a new file /proc/tty/consoles"
This reverts commit f4a3e0bceb.  Jiri
Sladby points out that the tty structure we're using may already be
gone, and Al Viro doesn't hold back in complaining about the random
loading of 'filp->private_data' which doesn't have to be a pointer at
all, nor does checking the magic field for TTY_MAGIC prove anything.

Belated review by Al:

 "a) global variable depending on stdin of the last opener? Affecting
     output of read(2)? Really?

  b) iterator is broken; list should be locked in ->start(), unlocked in
     ->stop() and *NOT* unlocked/relocked in ->next()

  c) ->show() ought to do nothing in case of ->device == NULL, instead
     of skipping those in ->next()/->start()

  d) regardless of the merits of the bright idea about asterisk at that
     line in output *and* regardless of (a), the implementation is not
     only atrociously ugly, it's actually very likely to be a roothole.
     Verifying that Cthulhu knows what number happens to be address of a
     tty_struct by blindly dereferencing memory at that address...
     Ouch.

  Please revert that crap."

And Christoph pipes in and NAK's the approach of walking fd tables etc
too.  So it's pretty unanimous.

Noticed-by: Jri Slaby <jslaby@suse.cz>
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Werner Fink <werner@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-23 08:14:12 -07:00
Linus Torvalds 73ecf3a6e3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (49 commits)
  serial8250: ratelimit "too much work" error
  serial: bfin_sport_uart: speed up sport RX sample rate to be 3% faster
  serial: abstraction for 8250 legacy ports
  serial/imx: check that the buffer is non-empty before sending it out
  serial: mfd: add more baud rates support
  jsm: Remove the uart port on errors
  Alchemy: Add UART PM methods.
  8250: allow platforms to override PM hook.
  altera_uart: Don't use plain integer as NULL pointer
  altera_uart: Fix missing prototype for registering an early console
  altera_uart: Fixup type usage of port flags
  altera_uart: Make it possible to use Altera UART and 8250 ports together
  altera_uart: Add support for different address strides
  altera_uart: Add support for getting mapbase and IRQ from resources
  altera_uart: Add support for polling mode (IRQ-less)
  serial: Factor out uart_poll_timeout() from 8250 driver
  serial: mark the 8250 driver as maintained
  serial: 8250: Don't delay after transmitter is ready.
  tty: MAINTAINERS: add drivers/serial/jsm/ as maintained driver
  vcs: invoke the vt update callback when /dev/vcs* is written to
  ...
2010-10-22 19:59:04 -07:00
Dr. Werner Fink f4a3e0bceb tty: Add a new file /proc/tty/consoles
Add a new file /proc/tty/consoles to be able to determine the registered
system console lines.  If the reading process holds /dev/console open at
the regular standard input stream the active device will be marked by an
asterisk.  Show possible operations and also decode the used flags of
the listed console lines.

Signed-off-by: Werner Fink <werner@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:20:05 -07:00
Tristan Ye 7bdb0d18bf ocfs2: Add a mount option "coherency=*" to handle cluster coherency for O_DIRECT writes.
Currently, the default behavior of O_DIRECT writes was allowing
concurrent writing among nodes to the same file, with no cluster
coherency guaranteed (no EX lock held).  This can leave stale data in
the cache for buffered reads on other nodes.

The new mount option introduce a chance to choose two different
behaviors for O_DIRECT writes:

    * coherency=full, as the default value, will disallow
                      concurrent O_DIRECT writes by taking
                      EX locks.

    * coherency=buffered, allow concurrent O_DIRECT writes
                          without EX lock among nodes, which
                          gains high performance at risk of
                          getting stale data on other nodes.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-10-11 14:14:55 -07:00
Bryan Schumaker 955a857e06 NFS: new idmapper
This patch creates a new idmapper system that uses the request-key function to
place a call into userspace to map user and group ids to names.  The old
idmapper was single threaded, which prevented more than one request from running
at a single time.  This means that a user would have to wait for an upcall to
finish before accessing a cached result.

The upcall result is stored on a keyring of type id_resolver.  See the file
Documentation/filesystems/nfs/idmapper.txt for instructions.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
[Trond: fix up the return value of nfs_idmap_lookup_name and clean up code]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-07 18:48:49 -04:00
Arnd Bergmann 2116b7a473 smbfs: move to drivers/staging
smbfs has been scheduled for removal in 2.6.27, so
maybe we can now move it to drivers/staging on the
way out.

smbfs still uses the big kernel lock and nobody
is going to fix that, so we should be getting
rid of it soon.

This removes the 32 bit compat mount and ioctl
handling code, which is implemented in common fs
code, and moves all smbfs related files into
drivers/staging/smbfs.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-05 09:08:21 -07:00
Chuck Lever 306a075362 NFS: Allow NFSROOT debugging messages to be enabled dynamically
As a convenience, introduce a kernel command line option to enable
NFSROOT debugging messages.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-17 10:54:37 -04:00
Arnd Bergmann b19dd42faf bkl: Remove locked .ioctl file operation
The last user is gone, so we can safely remove this

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: John Kacur <jkacur@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-08-14 00:24:24 +02:00
Linus Torvalds 062e27ec1b Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: fix checkpatch.pl warnings
  Squashfs: fix filename typo
  Squashfs: update Kconfig and documentation for LZO
  Squashfs: fix block size use in LZO decompressor
  Squashfs: Add LZO compression support
  squashfs: fix filename in header comment
  Squashfs: Make XATTR config name consistent with other file systems
  squashfs: fix compiler inline warning
2010-08-11 09:20:13 -07:00
Linus Torvalds 5f248c9c25 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
  no need for list_for_each_entry_safe()/resetting with superblock list
  Fix sget() race with failing mount
  vfs: don't hold s_umount over close_bdev_exclusive() call
  sysv: do not mark superblock dirty on remount
  sysv: do not mark superblock dirty on mount
  btrfs: remove junk sb_dirt change
  BFS: clean up the superblock usage
  AFFS: wait for sb synchronization when needed
  AFFS: clean up dirty flag usage
  cifs: truncate fallout
  mbcache: fix shrinker function return value
  mbcache: Remove unused features
  add f_flags to struct statfs(64)
  pass a struct path to vfs_statfs
  update VFS documentation for method changes.
  All filesystems that need invalidate_inode_buffers() are doing that explicitly
  convert remaining ->clear_inode() to ->evict_inode()
  Make ->drop_inode() just return whether inode needs to be dropped
  fs/inode.c:clear_inode() is gone
  fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
  ...

Fix up trivial conflicts in fs/nilfs2/super.c
2010-08-10 11:26:52 -07:00
David Rientjes 51b1bd2ace oom: deprecate oom_adj tunable
/proc/pid/oom_adj is now deprecated so that that it may eventually be
removed.  The target date for removal is August 2012.

A warning will be printed to the kernel log if a task attempts to use this
interface.  Future warning will be suppressed until the kernel is rebooted
to prevent spamming the kernel log.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:02 -07:00
David Rientjes a63d83f427 oom: badness heuristic rewrite
This a complete rewrite of the oom killer's badness() heuristic which is
used to determine which task to kill in oom conditions.  The goal is to
make it as simple and predictable as possible so the results are better
understood and we end up killing the task which will lead to the most
memory freeing while still respecting the fine-tuning from userspace.

Instead of basing the heuristic on mm->total_vm for each task, the task's
rss and swap space is used instead.  This is a better indication of the
amount of memory that will be freeable if the oom killed task is chosen
and subsequently exits.  This helps specifically in cases where KDE or
GNOME is chosen for oom kill on desktop systems instead of a memory
hogging task.

The baseline for the heuristic is a proportion of memory that each task is
currently using in memory plus swap compared to the amount of "allowable"
memory.  "Allowable," in this sense, means the system-wide resources for
unconstrained oom conditions, the set of mempolicy nodes, the mems
attached to current's cpuset, or a memory controller's limit.  The
proportion is given on a scale of 0 (never kill) to 1000 (always kill),
roughly meaning that if a task has a badness() score of 500 that the task
consumes approximately 50% of allowable memory resident in RAM or in swap
space.

The proportion is always relative to the amount of "allowable" memory and
not the total amount of RAM systemwide so that mempolicies and cpusets may
operate in isolation; they shall not need to know the true size of the
machine on which they are running if they are bound to a specific set of
nodes or mems, respectively.

Root tasks are given 3% extra memory just like __vm_enough_memory()
provides in LSMs.  In the event of two tasks consuming similar amounts of
memory, it is generally better to save root's task.

Because of the change in the badness() heuristic's baseline, it is also
necessary to introduce a new user interface to tune it.  It's not possible
to redefine the meaning of /proc/pid/oom_adj with a new scale since the
ABI cannot be changed for backward compatability.  Instead, a new tunable,
/proc/pid/oom_score_adj, is added that ranges from -1000 to +1000.  It may
be used to polarize the heuristic such that certain tasks are never
considered for oom kill while others may always be considered.  The value
is added directly into the badness() score so a value of -500, for
example, means to discount 50% of its memory consumption in comparison to
other tasks either on the system, bound to the mempolicy, in the cpuset,
or sharing the same memory controller.

/proc/pid/oom_adj is changed so that its meaning is rescaled into the
units used by /proc/pid/oom_score_adj, and vice versa.  Changing one of
these per-task tunables will rescale the value of the other to an
equivalent meaning.  Although /proc/pid/oom_adj was originally defined as
a bitshift on the badness score, it now shares the same linear growth as
/proc/pid/oom_score_adj but with different granularity.  This is required
so the ABI is not broken with userspace applications and allows oom_adj to
be deprecated for future removal.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:02 -07:00
Al Viro 336fb3b97b update VFS documentation for method changes.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:48:40 -04:00
Christoph Hellwig 1e23173509 update documentation for the new truncate sequence
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:40 -04:00
Linus Torvalds a57f9a3e81 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (45 commits)
  nilfs2: reject filesystem with unsupported block size
  nilfs2: avoid rec_len overflow with 64KB block size
  nilfs2: simplify nilfs_get_page function
  nilfs2: reject incompatible filesystem
  nilfs2: add feature set fields to super block
  nilfs2: clarify byte offset in super block format
  nilfs2: apply read-ahead for nilfs_btree_lookup_contig
  nilfs2: introduce check flag to btree node buffer
  nilfs2: add btree get block function with readahead option
  nilfs2: add read ahead mode to nilfs_btnode_submit_block
  nilfs2: fix buffer head leak in nilfs_btnode_submit_block
  nilfs2: eliminate inline keywords in btree implementation
  nilfs2: get maximum number of child nodes from bmap object
  nilfs2: reduce repetitive calculation of max number of child nodes
  nilfs2: optimize calculation of min/max number of btree node children
  nilfs2: remove redundant pointer checks in bmap lookup functions
  nilfs2: get rid of nilfs_bmap_union
  nilfs2: unify bmap set_target_v operations
  nilfs2: get rid of nilfs_btree uses
  nilfs2: get rid of nilfs_direct uses
  ...
2010-08-07 13:10:55 -07:00
Linus Torvalds 3b7433b8a8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
  workqueue: mark init_workqueues() as early_initcall()
  workqueue: explain for_each_*cwq_cpu() iterators
  fscache: fix build on !CONFIG_SYSCTL
  slow-work: kill it
  gfs2: use workqueue instead of slow-work
  drm: use workqueue instead of slow-work
  cifs: use workqueue instead of slow-work
  fscache: drop references to slow-work
  fscache: convert operation to use workqueue instead of slow-work
  fscache: convert object to use workqueue instead of slow-work
  workqueue: fix how cpu number is stored in work->data
  workqueue: fix mayday_mask handling on UP
  workqueue: fix build problem on !CONFIG_SMP
  workqueue: fix locking in retry path of maybe_create_worker()
  async: use workqueue for worker pool
  workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
  workqueue: implement unbound workqueue
  workqueue: prepare for WQ_UNBOUND implementation
  libata: take advantage of cmwq and remove concurrency limitations
  workqueue: fix worker management invocation without pending works
  ...

Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
2010-08-07 12:42:58 -07:00
Linus Torvalds 1cfd2bda8c Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (30 commits)
  PCI: update for owner removal from struct device_attribute
  PCI: Fix warnings when CONFIG_DMI unset
  PCI: Do not run NVidia quirks related to MSI with MSI disabled
  x86/PCI: use for_each_pci_dev()
  PCI: use for_each_pci_dev()
  PCI: MSI: Restore read_msi_msg_desc(); add get_cached_msi_msg_desc()
  PCI: export SMBIOS provided firmware instance and label to sysfs
  PCI: Allow read/write access to sysfs I/O port resources
  x86/PCI: use host bridge _CRS info on ASRock ALiveSATA2-GLAN
  PCI: remove unused HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_{SIZE|BOUNDARY}
  PCI: disable mmio during bar sizing
  PCI: MSI: Remove unsafe and unnecessary hardware access
  PCI: Default PCIe ASPM control to on and require !EMBEDDED to disable
  PCI: kernel oops on access to pci proc file while hot-removal
  PCI: pci-sysfs: remove casts from void*
  ACPI: Disable ASPM if the platform won't provide _OSC control for PCIe
  PCI hotplug: make sure child bridges are enabled at hotplug time
  PCI hotplug: shpchp: Removed check for hotplug of display devices
  PCI hotplug: pciehp: Fixed return value sign for pciehp_unconfigure_device
  PCI: Don't enable aspm before drivers have had a chance to veto it
  ...
2010-08-06 11:44:36 -07:00
Phillip Lougher 4b676d2dbe Squashfs: update Kconfig and documentation for LZO
Update compression types supported and add some help text for
the LZO Kconfig option.

Also add missing "default n" line and make some trivial whitespace
cleanups too.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2010-08-05 23:42:54 +01:00
Ira Weiny a530703271 sysfs: Fix one more signature discrepancy between sysfs implementation and docs.
Signed-off-by: Ira Weiny <weiny2@llnl.gov>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-05 13:53:34 -07:00
Bart Van Assche 30a69000a4 sysfs: fix discrepancies between implementation and documentation
Fix all discrepancies I know of between the sysfs implementation and its
documentation.

Signed-off-by: Bart Van Assche <bart.vanassche@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-05 13:53:34 -07:00
Linus Torvalds 3cfc2c42c1 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (48 commits)
  Documentation: update broken web addresses.
  fix comment typo "choosed" -> "chosen"
  hostap:hostap_hw.c Fix typo in comment
  Fix spelling contorller -> controller in comments
  Kconfig.debug: FAIL_IO_TIMEOUT: typo Faul -> Fault
  fs/Kconfig: Fix typo Userpace -> Userspace
  Removing dead MACH_U300_BS26
  drivers/infiniband: Remove unnecessary casts of private_data
  fs/ocfs2: Remove unnecessary casts of private_data
  libfc: use ARRAY_SIZE
  scsi: bfa: use ARRAY_SIZE
  drm: i915: use ARRAY_SIZE
  drm: drm_edid: use ARRAY_SIZE
  synclink: use ARRAY_SIZE
  block: cciss: use ARRAY_SIZE
  comment typo fixes: charater => character
  fix comment typos concerning "challenge"
  arm: plat-spear: fix typo in kerneldoc
  reiserfs: typo comment fix
  update email address
  ...
2010-08-04 15:31:02 -07:00
Linus Torvalds 6ba74014c1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1443 commits)
  phy/marvell: add 88ec048 support
  igb: Program MDICNFG register prior to PHY init
  e1000e: correct MAC-PHY interconnect register offset for 82579
  hso: Add new product ID
  can: Add driver for esd CAN-USB/2 device
  l2tp: fix export of header file for userspace
  can-raw: Fix skb_orphan_try handling
  Revert "net: remove zap_completion_queue"
  net: cleanup inclusion
  phy/marvell: add 88e1121 interface mode support
  u32: negative offset fix
  net: Fix a typo from "dev" to "ndev"
  igb: Use irq_synchronize per vector when using MSI-X
  ixgbevf: fix null pointer dereference due to filter being set for VLAN 0
  e1000e: Fix irq_synchronize in MSI-X case
  e1000e: register pm_qos request on hardware activation
  ip_fragment: fix subtracting PPPOE_SES_HLEN from mtu twice
  net: Add getsockopt support for TCP thin-streams
  cxgb4: update driver version
  cxgb4: add new PCI IDs
  ...

Manually fix up conflicts in:
 - drivers/net/e1000e/netdev.c: due to pm_qos registration
   infrastructure changes
 - drivers/net/phy/marvell.c: conflict between adding 88ec048 support
   and cleaning up the IDs
 - drivers/net/wireless/ipw2x00/ipw2100.c: trivial ipw2100_pm_qos_req
   conflict (registration change vs marking it static)
2010-08-04 11:47:58 -07:00
Justin P. Mattock 0ea6e61122 Documentation: update broken web addresses.
Below you will find an updated version from the original series bunching all patches into one big patch
updating broken web addresses that are located in Documentation/*
Some of the addresses date as far far back as 1995 etc... so searching became a bit difficult,
the best way to deal with these is to use web.archive.org to locate these addresses that are outdated.
Now there are also some addresses pointing to .spec files some are located, but some(after searching
on the companies site)where still no where to be found. In this case I just changed the address
to the company site this way the users can contact the company and they can locate them for the users.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Thomas Weber <weber@corscience.de>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Cc: Paulo Marques <pmarques@grupopie.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-08-04 15:21:40 +02:00
Alex Williamson 8633328be2 PCI: Allow read/write access to sysfs I/O port resources
PCI sysfs resource files currently only allow mmap'ing.  On x86 this
works fine for memory backed BARs, but doesn't work at all for I/O
port backed BARs.  Add read/write to I/O port PCI sysfs resource
files to allow userspace access to these device regions.

Acked-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-07-30 09:32:08 -07:00
Christoph Hellwig a64afb057b xfs: remove obsolete osyncisosync mount option
Since Linux 2.6.33 the kernel has support for real O_SYNC, which made
the osyncisosync option a no-op.  Warn the users about this and remove
the mount flag for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-26 13:16:51 -05:00
Ryusuke Konishi 802d317754 nilfs2: add nodiscard mount option
Nilfs has "discard" mount option which issues discard/TRIM commands to
underlying block device, but it lacks a complementary option and has
no way to disable the feature through remount.

This adds "nodiscard" option to resolve this imbalance.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:12 +09:00
Ryusuke Konishi 773bc4f3b6 nilfs2: add barrier mount option
Nilfs enables write barriers by default and has "nobarrier" mount
option to disable this feature.  But it lacks the complementary option
and has no way to re-enable the feature on remount.

This adds "barrier" option to resolve this imbalance.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:12 +09:00
Tejun Heo 8b8edefa2f fscache: convert object to use workqueue instead of slow-work
Make fscache object state transition callbacks use workqueue instead
of slow-work.  New dedicated unbound CPU workqueue fscache_object_wq
is created.  get/put callbacks are renamed and modified to take
@object and called directly from the enqueue wrapper and the work
function.  While at it, make all open coded instances of get/put to
use fscache_get/put_object().

* Unbound workqueue is used.

* work_busy() output is printed instead of slow-work flags in object
  debugging outputs.  They mean basically the same thing bit-for-bit.

* sysctl fscache.object_max_active added to control concurrency.  The
  default value is nr_cpus clamped between 4 and
  WQ_UNBOUND_MAX_ACTIVE.

* slow_work_sleep_till_thread_needed() is replaced with fscache
  private implementation fscache_object_sleep_till_congested() which
  waits on fscache_object_wq congestion.

* debugfs support is dropped for now.  Tracing API based debug
  facility is planned to be added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
2010-07-22 22:58:34 +02:00
Alex Elder 1bf7dbfde8 Merge branch 'master' into for-linus 2010-06-04 13:22:30 -05:00
Wu Fengguang 8cbccbe761 ipconfig: document DHCP hostname and DNS record
Now it's possible to update the DNS record for $HOST_NAME with

	ip=::::$HOST_NAME::dhcp

CC: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-03 03:18:18 -07:00
Christoph Hellwig 99a4d54620 xfs: remove done roadmap item from xfs-delayed-logging-design.txt
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-06-03 16:22:29 +10:00
npiggin@suse.de 7bb46a6734 fs: introduce new truncate sequence
Introduce a new truncate calling sequence into fs/mm subsystems. Rather than
setattr > vmtruncate > truncate, have filesystems call their truncate sequence
from ->setattr if filesystem specific operations are required. vmtruncate is
deprecated, and truncate_pagecache and inode_newsize_ok helpers introduced
previously should be used.

simple_setattr is introduced for simple in-ram filesystems to implement
the new truncate sequence. Eventually all filesystems should be converted
to implement a setattr, and the default code in notify_change should go
away.

simple_setsize is also introduced to perform just the ATTR_SIZE portion
of simple_setattr (ie. changing i_size and trimming pagecache).

To implement the new truncate sequence:
- filesystem specific manipulations (eg freeing blocks) must be done in
  the setattr method rather than ->truncate.
- vmtruncate can not be used by core code to trim blocks past i_size in
  the event of write failure after allocation, so this must be performed
  in the fs code.
- convert usage of helpers block_write_begin, nobh_write_begin,
  cont_write_begin, and *blockdev_direct_IO* to use _newtrunc postfixed
  variants. These avoid calling vmtruncate to trim blocks (see previous).
- inode_setattr should not be used. generic_setattr is a new function
  to be used to copy simple attributes into the generic inode.
- make use of the better opportunity to handle errors with the new sequence.

Big problem with the previous calling sequence: the filesystem is not called
until i_size has already changed.  This means it is not allowed to fail the
call, and also it does not know what the previous i_size was. Also, generic
code calling vmtruncate to truncate allocated blocks in case of error had
no good way to return a meaningful error (or, for example, atomically handle
block deallocation).

Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-27 22:15:33 -04:00
Christoph Hellwig 7ea8085910 drop unused dentry argument to ->fsync
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-27 22:05:02 -04:00
Jan Blunck 866707fc27 Documentation/filesystems/Locking: update documentation on llseek() wrt BKL
The inode's i_size is not protected by the big kernel lock.  Therefore it
does not make sense to recommend taking the BKL in filesystems llseek
operations.  Instead it should use the inode's mutex or use just use
i_size_read() instead.  Add a note that this is not protecting
file->f_pos.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:56 -07:00
Linus Torvalds 63a6440326 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  squashfs: update documentation to include description of xattr layout
  squashfs: fix name reading in squashfs_xattr_get
  squashfs: constify xattr handlers
  squashfs: xattr fix sparse warnings
  squashfs: xattr_lookup sparse fix
  squashfs: add xattr support configure option
  squashfs: add new extended inode types
  squashfs: add support for xattr reading
  squashfs: add xattr id support
2010-05-26 08:57:20 -07:00
Phillip Lougher 899f453033 squashfs: update documentation to include description of xattr layout
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2010-05-26 01:12:26 +01:00
Linus Torvalds 110b93842e Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: Ensure inode allocation buffers are fully replayed
  xfs: enable background pushing of the CIL
  xfs: forced unmounts need to push the CIL
  xfs: Introduce delayed logging core code
  xfs: Delayed logging design documentation
  xfs: Improve scalability of busy extent tracking
  xfs: make the log ticket ID available outside the log infrastructure
  xfs: clean up log ticket overrun debug output
  xfs: Clean up XFS_BLI_* flag namespace
  xfs: modify buffer item reference counting
  xfs: allow log ticket allocation to take allocation flags
  xfs: Don't reuse the same transaction ID for duplicated transactions.
2010-05-25 08:17:01 -07:00
Lee Schermerhorn 971ada0f66 mempolicy: document cpuset interaction with tmpfs mpol mount option
Update Documentation/filesystems/tmpfs.txt to describe the interaction of
tmpfs mount option memory policy with tasks' cpuset mems_allowed.

Note: the mount(8) man page [in the util-linux-ng package] requires
similiar updates.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:57 -07:00
Alex Elder 88e88374ee Merge branch 'delayed-logging-for-2.6.35' into for-linus 2010-05-24 11:57:36 -05:00
Dave Chinner a9a745daad xfs: Delayed logging design documentation
Document the design of the delayed logging implementation. This
includes assumptions made, dead ends followed, the reasoning behind
the structuring of the code, the layout of various structures, how
things fit together, traps and pit-falls avoided, etc. This is all
too much to document in the code itself, so do it in a separate
file.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-24 10:35:39 -05:00
Linus Torvalds 7ce1418f95 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (31 commits)
  dquot: Detect partial write error to quota file in write_blk() and add printk_ratelimit for quota error messages
  ocfs2: Fix lock inversion in quotas during umount
  ocfs2: Use __dquot_transfer to avoid lock inversion
  ocfs2: Fix NULL pointer deref when writing local dquot
  ocfs2: Fix estimate of credits needed for quota allocation
  ocfs2: Fix quota locking
  ocfs2: Avoid unnecessary block mapping when refreshing quota info
  ocfs2: Do not map blocks from local quota file on each write
  quota: Refactor dquot_transfer code so that OCFS2 can pass in its references
  quota: unify quota init condition in setattr
  quota: remove sb_has_quota_active in get/set_info
  quota: unify ->set_dqblk
  quota: unify ->get_dqblk
  ext3: make barrier options consistent with ext4
  quota: Make quota stat accounting lockless.
  suppress warning: "quotatypes" defined but not used
  ext3: Fix waiting on transaction during fsync
  jbd: Provide function to check whether transaction will issue data barrier
  ufs: add ufs speciffic ->setattr call
  BKL: Remove BKL from ext2 filesystem
  ...
2010-05-21 10:50:28 -07:00
Eric Sandeen 0636c73ee7 ext3: make barrier options consistent with ext4
ext4 was updated to accept barrier/nobarrier mount options
in addition to the older barrier=0/1.  The barrier story
is complex enough, we should help people by making the options
the same at least, even if the defaults are different.

This patch allows the barrier/nobarrier mount options for ext3,
while keeping nobarrier the default.

It also unconditionally displays barrier status in show_options,
and prints a message at mount time if barriers are not enabled,
just as ext4 does.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:41 +02:00
Serge E. Hallyn b9d8b45ee3 sysfs-namespaces: add a high-level Documentation file
The first three paragraphs are almost verbatim taken from Eric's
commit message on the patch introducing network ns tags.  The next
two paragraphs I wrote to be a brief high level overview.  The last
section is taken from the commit message on "Implement sysfs tagged
directory support", but updated.  Hopefully correctly.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Linus Torvalds d7dbf4ffee Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (23 commits)
  nilfs2: disallow remount of snapshot from/to a regular mount
  nilfs2: use huge_encode_dev/huge_decode_dev
  nilfs2: update comment on deactivate_super at nilfs_get_sb
  nilfs2: replace MS_VERBOSE with MS_SILENT
  nilfs2: add missing initialization of s_mode
  nilfs2: fix misuse of open_bdev_exclusive/close_bdev_exclusive
  nilfs2: enlarge s_volume_name member in nilfs_super_block
  nilfs2: use checkpoint number instead of timestamp to select super block
  nilfs2: add missing endian conversion on super block magic number
  nilfs2: make nilfs_sc_*_ops static
  nilfs2: add kernel doc comments to persistent object allocator functions
  nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info
  nilfs2: remove nilfs_segctor_init() in segment.c
  nilfs2: insert checkpoint number in segment summary header
  nilfs2: add a print message after loading nilfs2
  nilfs2: cleanup multi kmem_cache_{create,destroy} code
  nilfs2: move out checksum routines to segment buffer code
  nilfs2: move pointer to super root block into logs
  nilfs2: change default of 'errors' mount option to 'remount-ro' mode
  nilfs2: Combine nilfs_btree_release_path() and nilfs_btree_free_path()
  ...
2010-05-21 07:47:00 -07:00
Linus Torvalds 677abe49ad Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
  GFS2: Fix typo
  GFS2: stuck in inode wait, no glocks stuck
  GFS2: Eliminate useless err variable
  GFS2: Fix writing to non-page aligned gfs2_quota structures
  GFS2: Add some useful messages
  GFS2: fix quota state reporting
  GFS2: Various gfs2_logd improvements
  GFS2: glock livelock
  GFS2: Clean up stuffed file copying
  GFS2: docs update
  GFS2: Remove space from slab cache name
2010-05-21 07:29:15 -07:00
Linus Torvalds 03e62303cf Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (47 commits)
  ocfs2: Silence a gcc warning.
  ocfs2: Don't retry xattr set in case value extension fails.
  ocfs2:dlm: avoid dlm->ast_lock lockres->spinlock dependency break
  ocfs2: Reset xattr value size after xa_cleanup_value_truncate().
  fs/ocfs2/dlm: Use kstrdup
  fs/ocfs2/dlm: Drop memory allocation cast
  Ocfs2: Optimize punching-hole code.
  Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.
  Ocfs2: Fix hole punching to correctly do CoW during cluster zeroing.
  Ocfs2: Optimize ocfs2 truncate to use ocfs2_remove_btree_range() instead.
  ocfs2: Block signals for mkdir/link/symlink/O_CREAT.
  ocfs2: Wrap signal blocking in void functions.
  ocfs2/dlm: Increase o2dlm lockres hash size
  ocfs2: Make ocfs2_extend_trans() really extend.
  ocfs2/trivial: Code cleanup for allocation reservation.
  ocfs2: make ocfs2_adjust_resv_from_alloc simple.
  ocfs2: Make nointr a default mount option
  ocfs2/dlm: Make o2dlm domain join/leave messages KERN_NOTICE
  o2net: log socket state changes
  ocfs2: print node # when tcp fails
  ...
2010-05-21 07:20:17 -07:00
Linus Torvalds f39d01be4c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits)
  vlynq: make whole Kconfig-menu dependant on architecture
  add descriptive comment for TIF_MEMDIE task flag declaration.
  EEPROM: max6875: Header file cleanup
  EEPROM: 93cx6: Header file cleanup
  EEPROM: Header file cleanup
  agp: use NULL instead of 0 when pointer is needed
  rtc-v3020: make bitfield unsigned
  PCI: make bitfield unsigned
  jbd2: use NULL instead of 0 when pointer is needed
  cciss: fix shadows sparse warning
  doc: inode uses a mutex instead of a semaphore.
  uml: i386: Avoid redefinition of NR_syscalls
  fix "seperate" typos in comments
  cocbalt_lcdfb: correct sections
  doc: Change urls for sparse
  Powerpc: wii: Fix typo in comment
  i2o: cleanup some exit paths
  Documentation/: it's -> its where appropriate
  UML: Fix compiler warning due to missing task_struct declaration
  UML: add kernel.h include to signal.c
  ...
2010-05-20 09:20:59 -07:00
Linus Torvalds f72caf7e49 Merge branch 'for-2.6.35' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.35' of git://linux-nfs.org/~bfields/linux: (45 commits)
  Revert "nfsd4: distinguish expired from stale stateids"
  nfsd: safer initialization order in find_file()
  nfs4: minor callback code simplification, comment
  NFSD: don't report compiled-out versions as present
  nfsd4: implement reclaim_complete
  nfsd4: nfsd4_destroy_session must set callback client under the state lock
  nfsd4: keep a reference count on client while in use
  nfsd4: mark_client_expired
  nfsd4: introduce nfs4_client.cl_refcount
  nfsd4: refactor expire_client
  nfsd4: extend the client_lock to cover cl_lru
  nfsd4: use list_move in move_to_confirmed
  nfsd4: fold release_session into expire_client
  nfsd4: rename sessionid_lock to client_lock
  nfsd4: fix bare destroy_session null dereference
  nfsd4: use local variable in nfs4svc_encode_compoundres
  nfsd: further comment typos
  sunrpc: centralise most calls to svc_xprt_received
  nfsd4: fix unlikely race in session replay case
  nfsd4: fix filehandle comment
  ...
2010-05-19 17:24:54 -07:00
Linus Torvalds 6e0b7b2c39 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Clear CPU mask in affinity_hint when none is provided
  genirq: Add CPU mask affinity hint
  genirq: Remove IRQF_DISABLED from core code
  genirq: Run irq handlers with interrupts disabled
  genirq: Introduce request_any_context_irq()
  genirq: Expose irq_desc->node in proc/irq

Fixed up trivial conflicts in Documentation/feature-removal-schedule.txt
2010-05-19 17:09:40 -07:00
J. Bruce Fields 4dc6ec00f6 nfsd4: implement reclaim_complete
This is a mandatory operation.  Also, here (not in open) is where we
should be committing the reboot recovery information.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13 12:03:11 -04:00
Robin Holt 34441427aa revert "procfs: provide stack information for threads" and its fixup commits
Originally, commit d899bf7b ("procfs: provide stack information for
threads") attempted to introduce a new feature for showing where the
threadstack was located and how many pages are being utilized by the
stack.

Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was
applied to fix the NO_MMU case.

Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on
64-bit") was applied to fix a bug in ia32 executables being loaded.

Commit 9ebd4eba7 ("procfs: fix /proc/<pid>/stat stack pointer for kernel
threads") was applied to fix a bug which had kernel threads printing a
userland stack address.

Commit 1306d603f ('proc: partially revert "procfs: provide stack
information for threads"') was then applied to revert the stack pages
being used to solve a significant performance regression.

This patch nearly undoes the effect of all these patches.

The reason for reverting these is it provides an unusable value in
field 28.  For x86_64, a fork will result in the task->stack_start
value being updated to the current user top of stack and not the stack
start address.  This unpredictability of the stack_start value makes
it worthless.  That includes the intended use of showing how much stack
space a thread has.

Other architectures will get different values.  As an example, ia64
gets 0.  The do_fork() and copy_process() functions appear to treat the
stack_start and stack_size parameters as architecture specific.

I only partially reverted c44972f1 ("procfs: disable per-task stack usage
on NOMMU") .  If I had completely reverted it, I would have had to change
mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is
configured.  Since I could not test the builds without significant effort,
I decided to not change mm/Makefile.

I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack
information for threads on 64-bit") .  I left the KSTK_ESP() change in
place as that seemed worthwhile.

Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-11 17:33:41 -07:00
Thadeu Lima de Souza Cascardo ca0dbd86b1 doc: inode uses a mutex instead of a semaphore.
Replace the introduced i_sem by an i_mutex in the filesystem locking
documentation. This was introduced [1] after all occurrences were
already replaced in the same text [2]. However, the term "inode
semaphore" has not been replaced then, and it's replaced now.

[1] afddba49d1
[2] a7bc02f4f4

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-05-10 23:42:27 +02:00
Anand Gadiyar a8cd4561ea fix "seperate" typos in comments
s/seperate/separate

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-05-10 11:56:30 +02:00
Ryusuke Konishi 277a6a3417 nilfs2: change default of 'errors' mount option to 'remount-ro' mode
Like ext3, nilfs has 'errors' mount option to allow specifying desired
behavior on severe errors.

Currently, the default action is 'errors=continue' and has potential
to advance filesystem corruption for severe errors.

This will change the action to 'errors=remount-ro' to avoid the issue.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-05-10 11:32:30 +09:00
Mark Fasheh 83f92318fa ocfs2: Add dir_resv_level mount option
The default behavior for directory reservations stays the same, but we add a
mount option so people can tweak the size of directory reservations
according to their workloads.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-05-05 18:18:07 -07:00
Mark Fasheh b07f8f24df ocfs2: change default reservation window sizes
The default reservation size of 4 (32-bit windows) is a bit too ambitious.
Scale it back to 16 bits (resv_level=2). I have been testing various sizes
on a 4-node cluster which runs a mixed workload that is heavily threaded.
With a 256MB local alloc, I get *roughly* the following levels of average file
fragmentation:

resv_level=0	70%
resv_level=1	21%
resv_level=2	23%
resv_level=3	24%
resv_level=4	60%
resv_level=5	did not test
resv_level=6	60%

resv_level=2 seemed like a good compromise between not letting windows be
too small, but not so big that heavier workloads will immediately suffer
without tuning.

This patch also change the behavior of directory reservations - they now
track file reservations.  The previous compromise of giving directory
windows only 8 bits wound up fragmenting more at some window sizes because
file allocations had smaller unused windows to poach from.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-05-05 18:18:07 -07:00
Mark Fasheh d02f00cc05 ocfs2: allocation reservations
This patch improves Ocfs2 allocation policy by allowing an inode to
reserve a portion of the local alloc bitmap for itself. The reserved
portion (allocation window) is advisory in that other allocation
windows might steal it if the local alloc bitmap becomes
full. Otherwise, the reservations are honored and guaranteed to be
free. When the local alloc window is moved to a different portion of
the bitmap, existing reservations are discarded.

Reservation windows are represented internally by a red-black
tree. Within that tree, each node represents the reservation window of
one inode. An LRU of active reservations is also maintained. When new
data is written, we allocate it from the inodes window. When all bits
in a window are exhausted, we allocate a new one as close to the
previous one as possible. Should we not find free space, an existing
reservation is pulled off the LRU and cannibalized.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2010-05-05 18:17:30 -07:00
Francis Galiegue a33f32244d Documentation/: it's -> its where appropriate
Fix obvious cases of "it's" being used when "its" was meant.

Signed-off-by: Francis Galiegue <fgaliegue@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-04-23 02:09:52 +02:00
Jiri Kosina 6c9468e9eb Merge branch 'master' into for-next 2010-04-23 02:08:44 +02:00
Thomas Gleixner 7c7145f6ac Merge branch 'linus' into irq/core
Reason: Get the upstream IRQF_DISABLED related changes.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-04-13 14:12:17 +02:00
Sripathi Kodi 9208d24253 9p: documentation update
This patch adds documentation for new 9P options introduced in
2.6.34.

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-04-05 10:37:36 -05:00
Linus Torvalds 9f32160372 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (28 commits)
  ceph: update discussion list address in MAINTAINERS
  ceph: some documentations fixes
  ceph: fix use after free on mds __unregister_request
  ceph: avoid loaded term 'OSD' in documention
  ceph: fix possible double-free of mds request reference
  ceph: fix session check on mds reply
  ceph: handle kmalloc() failure
  ceph: propagate mds session allocation failures to caller
  ceph: make write_begin wait propagate ERESTARTSYS
  ceph: fix snap rebuild condition
  ceph: avoid reopening osd connections when address hasn't changed
  ceph: rename r_sent_stamp r_stamp
  ceph: fix connection fault con_work reentrancy problem
  ceph: prevent dup stale messages to console for restarting mds
  ceph: fix pg pool decoding from incremental osdmap update
  ceph: fix mds sync() race with completing requests
  ceph: only release unused caps with mds requests
  ceph: clean up handle_cap_grant, handle_caps wrt session mutex
  ceph: fix session locking in handle_caps, ceph_check_caps
  ceph: drop unnecessary WARN_ON in caps migration
  ...
2010-03-29 14:42:25 -07:00
Cheng Renquan 8136b58dd0 ceph: some documentations fixes
New documentation should have an entry in the 00-INDEX.  Correct git
urls.

Signed-off-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-29 09:52:11 -07:00
Andrea Gelmini 4cb947b59c GFS2: docs update
Now http://sources.redhat.com/cluster/ is redirected to
http://sources.redhat.com/cluster/wiki/

Also fixed tabs in the end.

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2010-03-29 14:28:52 +01:00
KOSAKI Motohiro 5574169613 doc: add the documentation for mpol=local
commit 3f226aa1c (mempolicy: support mpol=local tmpfs mount option) added
new mpol=local mount option.  but it didn't add a documentation.

This patch does it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-24 16:31:21 -07:00
Dimitri Sivanich 92d6b71ab9 genirq: Expose irq_desc->node in proc/irq
Expose irq_desc->node as /proc/irq/*/node.

This file provides device hardware locality information for apps
desiring to include hardware locality in irq mapping decisions.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-03-24 14:10:03 +01:00
Sage Weil 23ab15ad7a ceph: avoid loaded term 'OSD' in documention
'OSD' means different things to different people; avoid it here to avoid
confusion.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23 07:47:07 -07:00
Linus Torvalds fc7f99cf36 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (205 commits)
  ceph: update for write_inode API change
  ceph: reset osd after relevant messages timed out
  ceph: fix flush_dirty_caps race with caps migration
  ceph: include migrating caps in issued set
  ceph: fix osdmap decoding when pools include (removed) snaps
  ceph: return EBADF if waiting for caps on closed file
  ceph: set osd request message front length correctly
  ceph: reset front len on return to msgpool; BUG on mismatched front iov
  ceph: fix snaptrace decoding on cap migration between mds
  ceph: use single osd op reply msg
  ceph: reset bits on connection close
  ceph: remove bogus mds forward warning
  ceph: remove fragile __map_osds optimization
  ceph: fix connection fault STANDBY check
  ceph: invalidate_authorizer without con->mutex held
  ceph: don't clobber write return value when using O_SYNC
  ceph: fix client_request_forward decoding
  ceph: drop messages on unregistered mds sessions; cleanup
  ceph: fix comments, locking in destroy_inode
  ceph: move dereference after NULL test
  ...

Fix trivial conflicts in Documentation/ioctl/ioctl-number.txt
2010-03-19 09:43:06 -07:00
Rob Landley 32e688b8c1 Documentation/filesystems/proc.txt typo fix.
Typo fix for a filename in procfs documentation.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-15 15:21:31 +01:00
Linus Torvalds c32da02342 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (56 commits)
  doc: fix typo in comment explaining rb_tree usage
  Remove fs/ntfs/ChangeLog
  doc: fix console doc typo
  doc: cpuset: Update the cpuset flag file
  Fix of spelling in arch/sparc/kernel/leon_kernel.c no longer needed
  Remove drivers/parport/ChangeLog
  Remove drivers/char/ChangeLog
  doc: typo - Table 1-2 should refer to "status", not "statm"
  tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in comments
  No need to patch AMD-provided drivers/gpu/drm/radeon/atombios.h
  devres/irq: Fix devm_irq_match comment
  Remove reference to kthread_create_on_cpu
  tree-wide: Assorted spelling fixes
  tree-wide: fix 'lenght' typo in comments and code
  drm/kms: fix spelling in error message
  doc: capitalization and other minor fixes in pnp doc
  devres: typo fix s/dev/devm/
  Remove redundant trailing semicolons from macros
  fix typo "definetly" -> "definitely" in comment
  tree-wide: s/widht/width/g typo in comments
  ...

Fix trivial conflict in Documentation/laptops/00-INDEX
2010-03-12 16:04:50 -08:00
Randy Dunlap 1e0051ae48 Documentation/fs/: split txt and source files
Make dnotify_test.c source file and add it to Makefile so that
bitrot can be prevented.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:35 -08:00
Jiri Kosina 318ae2edc3 Merge branch 'for-next' into for-linus
Conflicts:
	Documentation/filesystems/proc.txt
	arch/arm/mach-u300/include/mach/debug-macro.S
	drivers/net/qlge/qlge_ethtool.c
	drivers/net/qlge/qlge_main.c
	drivers/net/typhoon.c
2010-03-08 16:55:37 +01:00
Linus Torvalds 66b89159c2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs
* git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs:
  [LogFS] Change magic number
  [LogFS] Remove h_version field
  [LogFS] Check feature flags
  [LogFS] Only write journal if dirty
  [LogFS] Fix bdev erases
  [LogFS] Silence gcc
  [LogFS] Prevent 64bit divisions in hash_index
  [LogFS] Plug memory leak on error paths
  [LogFS] Add MAINTAINERS entry
  [LogFS] add new flash file system

Fixed up trivial conflict in lib/Kconfig, and a semantic conflict in
fs/logfs/inode.c introduced by write_inode() being changed to use
writeback_control' by commit a9185b41a4
("pass writeback_control to ->write_inode")
2010-03-06 13:18:03 -08:00
Linus Torvalds 05c5cb31ec Merge branch 'for-2.6.34' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.34' of git://linux-nfs.org/~bfields/linux: (22 commits)
  nfsd4: fix minor memory leak
  svcrpc: treat uid's as unsigned
  nfsd: ensure sockets are closed on error
  Revert "sunrpc: move the close processing after do recvfrom method"
  Revert "sunrpc: fix peername failed on closed listener"
  sunrpc: remove unnecessary svc_xprt_put
  NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN
  xfs_export_operations.commit_metadata
  commit_metadata export operation replacing nfsd_sync_dir
  lockd: don't clear sm_monitored on nsm_reboot_lookup
  lockd: release reference to nsm_handle in nlm_host_rebooted
  nfsd: Use vfs_fsync_range() in nfsd_commit
  NFSD: Create PF_INET6 listener in write_ports
  SUNRPC: NFS kernel APIs shouldn't return ENOENT for "transport not found"
  SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt()
  NFSD: Support AF_INET6 in svc_addsock() function
  SUNRPC: Use rpc_pton() in ip_map_parse()
  nfsd: 4.1 has an rfc number
  nfsd41: Create the recovery entry for the NFSv4.1 client
  nfsd: use vfs_fsync for non-directories
  ...
2010-03-06 11:31:38 -08:00
Mel Gorman a1b57ac061 mm: document /proc/pagetypeinfo
Add documentation for /proc/pagetypeinfo.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:26 -08:00
KAMEZAWA Hiroyuki b084d4353f mm: count swap usage
A frequent questions from users about memory management is what numbers of
swap ents are user for processes.  And this information will give some
hints to oom-killer.

Besides we can count the number of swapents per a process by scanning
/proc/<pid>/smaps, this is very slow and not good for usual process
information handler which works like 'ps' or 'top'.  (ps or top is now
enough slow..)

This patch adds a counter of swapents to mm_counter and update is at each
swap events.  Information is exported via /proc/<pid>/status file as

[kamezawa@bluextal memory]$ cat /proc/self/status
Name:   cat
State:  R (running)
Tgid:   2910
Pid:    2910
PPid:   2823
TracerPid:      0
Uid:    500     500     500     500
Gid:    500     500     500     500
FDSize: 256
Groups: 500
VmPeak:    82696 kB
VmSize:    82696 kB
VmLck:         0 kB
VmHWM:       432 kB
VmRSS:       432 kB
VmData:      172 kB
VmStk:        84 kB
VmExe:        48 kB
VmLib:      1568 kB
VmPTE:        40 kB
VmSwap:        0 kB <=============== this.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:24 -08:00
KAMEZAWA Hiroyuki 34e55232e5 mm: avoid false sharing of mm_counter
Considering the nature of per mm stats, it's the shared object among
threads and can be a cache-miss point in the page fault path.

This patch adds per-thread cache for mm_counter.  RSS value will be
counted into a struct in task_struct and synchronized with mm's one at
events.

Now, in this patch, the event is the number of calls to handle_mm_fault.
Per-thread value is added to mm at each 64 calls.

 rough estimation with small benchmark on parallel thread (2threads) shows
 [before]
     4.5 cache-miss/faults
 [after]
     4.0 cache-miss/faults
 Anyway, the most contended object is mmap_sem if the number of threads grows.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:24 -08:00
Linus Torvalds e213e26ab3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits)
  quota: stop using QUOTA_OK / NO_QUOTA
  dquot: cleanup dquot initialize routine
  dquot: move dquot initialization responsibility into the filesystem
  dquot: cleanup dquot drop routine
  dquot: move dquot drop responsibility into the filesystem
  dquot: cleanup dquot transfer routine
  dquot: move dquot transfer responsibility into the filesystem
  dquot: cleanup inode allocation / freeing routines
  dquot: cleanup space allocation / freeing routines
  ext3: add writepage sanity checks
  ext3: Truncate allocated blocks if direct IO write fails to update i_size
  quota: Properly invalidate caches even for filesystems with blocksize < pagesize
  quota: generalize quota transfer interface
  quota: sb_quota state flags cleanup
  jbd: Delay discarding buffers in journal_unmap_buffer
  ext3: quota_write cross block boundary behaviour
  quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota
  quota: split out compat_sys_quotactl support from quota.c
  quota: split out netlink notification support from quota.c
  quota: remove invalid optimization from quota_sync_all
  ...

Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c
2010-03-05 13:20:53 -08:00
Christoph Hellwig 871a293155 dquot: cleanup dquot initialize routine
Get rid of the initialize dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_initialize helper to __dquot_initialize
and vfs_dq_init to dquot_initialize to have a consistent namespace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:30 +01:00
Christoph Hellwig 9f75475802 dquot: cleanup dquot drop routine
Get rid of the drop dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_drop helper to __dquot_drop
and vfs_dq_drop to dquot_drop to have a consistent namespace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:30 +01:00
Christoph Hellwig b43fa8284d dquot: cleanup dquot transfer routine
Get rid of the transfer dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_transfer helper to __dquot_transfer
and vfs_dq_transfer to dquot_transfer to have a consistent namespace,
and make the new dquot_transfer return a normal negative errno value
which all callers expect.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:29 +01:00
Christoph Hellwig 63936ddaa1 dquot: cleanup inode allocation / freeing routines
Get rid of the alloc_inode and free_inode dquot operations - they are
always called from the filesystem and if a filesystem really needs
their own (which none currently does) it can just call into it's
own routine directly.

Also get rid of the vfs_dq_alloc/vfs_dq_free wrappers and always
call the lowlevel dquot_alloc_inode / dqout_free_inode routines
directly, which now lose the number argument which is always 1.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:28 +01:00
Christoph Hellwig 5dd4056db8 dquot: cleanup space allocation / freeing routines
Get rid of the alloc_space, free_space, reserve_space, claim_space and
release_rsv dquot operations - they are always called from the filesystem
and if a filesystem really needs their own (which none currently does)
it can just call into it's own routine directly.

Move shared logic into the common __dquot_alloc_space,
dquot_claim_space_nodirty and __dquot_free_space low-level methods,
and rationalize the wrappers around it to move as much as possible
code into the common block for CONFIG_QUOTA vs not.  Also rename
all these helpers to be named dquot_* instead of vfs_dq_*.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:28 +01:00
Linus Torvalds 0f2cc4ecd8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
  init: Open /dev/console from rootfs
  mqueue: fix typo "failues" -> "failures"
  mqueue: only set error codes if they are really necessary
  mqueue: simplify do_open() error handling
  mqueue: apply mathematics distributivity on mq_bytes calculation
  mqueue: remove unneeded info->messages initialization
  mqueue: fix mq_open() file descriptor leak on user-space processes
  fix race in d_splice_alias()
  set S_DEAD on unlink() and non-directory rename() victims
  vfs: add NOFOLLOW flag to umount(2)
  get rid of ->mnt_parent in tomoyo/realpath
  hppfs can use existing proc_mnt, no need for do_kern_mount() in there
  Mirror MS_KERNMOUNT in ->mnt_flags
  get rid of useless vfsmount_lock use in put_mnt_ns()
  Take vfsmount_lock to fs/internal.h
  get rid of insanity with namespace roots in tomoyo
  take check for new events in namespace (guts of mounts_poll()) to namespace.c
  Don't mess with generic_permission() under ->d_lock in hpfs
  sanitize const/signedness for udf
  nilfs: sanitize const/signedness in dealing with ->d_name.name
  ...

Fix up fairly trivial (famous last words...) conflicts in
drivers/infiniband/core/uverbs_main.c and security/tomoyo/realpath.c
2010-03-04 08:15:33 -08:00
Al Viro 2f99cc6e46 add several pieces to shared subtree documentation
* document locking
* add the missing part of data structure invariants (relationship
between mnt_share and mnt_slave lists in case of a peer group
among slaves).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 13:00:23 -05:00
Linus Torvalds feaf77d51a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: add reader's lock for cno in nilfs_ioctl_sync
  nilfs2: delete unnecessary condition in load_segment_summary
  nilfs2: move iterator to write log into segment buffer
  nilfs2: get rid of s_dirt flag use
  nilfs2: get rid of nilfs_segctor_req struct
  nilfs2: delete unnecessary condition in nilfs_dat_translate
  nilfs2: fix potential hang in nilfs_error on errors=remount-ro
  nilfs2: use mnt_want_write in ioctls where write access is needed
  nilfs2: issue discard request after cleaning segments
2010-03-03 08:53:49 -08:00
Mulyadi Santosa cb2992a60b doc: typo - Table 1-2 should refer to "status", not "statm"
Fixes a typo in proc.txt documentation. Table 1-2 should refer to
"status", not "statm"

Signed-off-by: Mulyadi Santosa <mulyadi.santosa@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-18 00:43:50 +01:00
Jiro SEKIBA e902ec9906 nilfs2: issue discard request after cleaning segments
This adds a function to send discard requests for given array of
segment numbers, and calls the function when garbage collection
succeeded.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-02-13 12:26:02 +09:00
J. Bruce Fields 73834d6f90 nfsd: 4.1 has an rfc number
No need to refer to an internet draft; there's an RFC now.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-01-20 17:17:04 -05:00
Paul E. McKenney 4c54005ca4 rcu: 1Q2010 update for RCU documentation
Add expedited functions.  Review documentation and update
obsolete verbiage.  Also fix the advice for the RCU CPU-stall
kernel configuration parameter, and document RCU CPU-stall
warnings.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <12635142581866-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:25:22 +01:00
KOSAKI Motohiro 1306d603fc proc: partially revert "procfs: provide stack information for threads"
Commit d899bf7b (procfs: provide stack information for threads) introduced
to show stack information in /proc/{pid}/status.  But it cause large
performance regression.  Unfortunately /proc/{pid}/status is used ps
command too and ps is one of most important component.  Because both to
take mmap_sem and page table walk are heavily operation.

If many process run, the ps performance is,

[before d899bf7b]

% perf stat ps >/dev/null

 Performance counter stats for 'ps':

     4090.435806  task-clock-msecs         #      0.032 CPUs
             229  context-switches         #      0.000 M/sec
               0  CPU-migrations           #      0.000 M/sec
             234  page-faults              #      0.000 M/sec
      8587565207  cycles                   #   2099.425 M/sec
      9866662403  instructions             #      1.149 IPC
      3789415411  cache-references         #    926.409 M/sec
        30419509  cache-misses             #      7.437 M/sec

   128.859521955  seconds time elapsed

[after d899bf7b]

% perf stat  ps  > /dev/null

 Performance counter stats for 'ps':

     4305.081146  task-clock-msecs         #      0.028 CPUs
             480  context-switches         #      0.000 M/sec
               2  CPU-migrations           #      0.000 M/sec
             237  page-faults              #      0.000 M/sec
      9021211334  cycles                   #   2095.480 M/sec
     10605887536  instructions             #      1.176 IPC
      3612650999  cache-references         #    839.160 M/sec
        23917502  cache-misses             #      5.556 M/sec

   152.277819582  seconds time elapsed

Thus, this patch revert it. Fortunately /proc/{pid}/task/{tid}/smaps
provide almost same information. we can use it.

Commit d899bf7b introduced two features:

 1) Add the annotattion of [thread stack: xxxx] mark to
    /proc/{pid}/task/{tid}/maps.
 2) Add StackUsage field to /proc/{pid}/status.

I only revert (2), because I haven't seen (1) cause regression.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-11 09:34:06 -08:00
Linus Torvalds a87da40875 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: update mailing list address
  nilfs2: Storage class should be before const qualifier
  nilfs2: trivial coding style fix
2010-01-04 12:28:26 -08:00
Ryusuke Konishi 6aff43f817 nilfs2: update mailing list address
This replaces the list address for nilfs discussion to linux-nilfs at
vger.kernel.org from users at nilfs.org.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-01-02 21:47:04 +09:00
Fang Wenqi 6d3b82f2d3 ext4: Update documentation to correct the inode_readahead_blks option name
Per commit 240799cd, the option name for readahead should be
inode_readahead_blks, not inode_readahead.

Signed-off-by: Fang Wenqi <antonf@turbolinux.com.cn>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-12-24 17:51:42 -05:00
Phil Carmody 099c2f21d8 Driver core: driver_attribute parameters can often be const*
Many struct driver_attribute descriptors are purely read-only
structures, and there's no need to change them. Therefore make
the promise not to, which will let those descriptors be put in
a ro section.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-23 11:23:43 -08:00
Phil Carmody 26579ab70a Driver core: device_attribute parameters can often be const*
Most device_attributes are const, and are begging to be
put in a ro section. However, the create and remove
file interfaces were failing to propagate the const promise
which the only functions they call offer.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-23 11:23:43 -08:00
Linus Torvalds 37c24b37fb Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.33' of git://linux-nfs.org/~bfields/linux: (42 commits)
  nfsd: remove pointless paths in file headers
  nfsd: move most of nfsfh.h to fs/nfsd
  nfsd: remove unused field rq_reffh
  nfsd: enable V4ROOT exports
  nfsd: make V4ROOT exports read-only
  nfsd: restrict filehandles accepted in V4ROOT case
  nfsd: allow exports of symlinks
  nfsd: filter readdir results in V4ROOT case
  nfsd: filter lookup results in V4ROOT case
  nfsd4: don't continue "under" mounts in V4ROOT case
  nfsd: introduce export flag for v4 pseudoroot
  nfsd: let "insecure" flag vary by pseudoflavor
  nfsd: new interface to advertise export features
  nfsd: Move private headers to source directory
  vfs: nfsctl.c un-used nfsd #includes
  lockd: Remove un-used nfsd headers #includes
  s390: remove un-used nfsd #includes
  sparc: remove un-used nfsd #includes
  parsic: remove un-used nfsd #includes
  compat.c: Remove dependence on nfsd private headers
  ...
2009-12-16 10:43:34 -08:00
Alexey Dobriyan 6be4b78993 seq_file: use proc_create() in documentation
Using create_proc_entry() + ->proc_fops assignment is racy because
->proc_fops will be NULL for some time, use proc_create() to avoid race.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:07 -08:00
john stultz 4614a696bd procfs: allow threads to rename siblings via /proc/pid/tasks/tid/comm
Setting a thread's comm to be something unique is a very useful ability
and is helpful for debugging complicated threaded applications.  However
currently the only way to set a thread name is for the thread to name
itself via the PR_SET_NAME prctl.

However, there may be situations where it would be advantageous for a
thread dispatcher to be naming the threads its managing, rather then
having the threads self-describe themselves.  This sort of behavior is
available on other systems via the pthread_setname_np() interface.

This patch exports a task's comm via proc/pid/comm and
proc/pid/task/tid/comm interfaces, and allows thread siblings to write to
these values.

[akpm@linux-foundation.org: cleanups]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Mike Fulton <fultonm@ca.ibm.com>
Cc: Sean Foley <Sean_Foley@ca.ibm.com>
Cc: Darren Hart <dvhltc@us.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:24 -08:00
Linus Torvalds 3126c136bc Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (21 commits)
  ext3: PTR_ERR return of wrong pointer in setup_new_group_blocks()
  ext3: Fix data / filesystem corruption when write fails to copy data
  ext4: Support for 64-bit quota format
  ext3: Support for vfsv1 quota format
  quota: Implement quota format with 64-bit space and inode limits
  quota: Move definition of QFMT_OCFS2 to linux/quota.h
  ext2: fix comment in ext2_find_entry about return values
  ext3: Unify log messages in ext3
  ext2: clear uptodate flag on super block I/O error
  ext2: Unify log messages in ext2
  ext3: make "norecovery" an alias for "noload"
  ext3: Don't update the superblock in ext3_statfs()
  ext3: journal all modifications in ext3_xattr_set_handle
  ext2: Explicitly assign values to on-disk enum of filetypes
  quota: Fix WARN_ON in lookup_one_len
  const: struct quota_format_ops
  ubifs: remove manual O_SYNC handling
  afs: remove manual O_SYNC handling
  kill wait_on_page_writeback_range
  vfs: Implement proper O_SYNC semantics
  ...
2009-12-11 15:31:13 -08:00
Linus Torvalds 4e2ccdb040 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (49 commits)
  nilfs2: separate wait function from nilfs_segctor_write
  nilfs2: add iterator for segment buffers
  nilfs2: hide nilfs_write_info struct in segment buffer code
  nilfs2: relocate io status variables to segment buffer
  nilfs2: do not return io error for bio allocation failure
  nilfs2: use list_splice_tail or list_splice_tail_init
  nilfs2: replace mark_inode_dirty as nilfs_mark_inode_dirty
  nilfs2: delete mark_inode_dirty in nilfs_delete_entry
  nilfs2: delete mark_inode_dirty in nilfs_commit_chunk
  nilfs2: change return type of nilfs_commit_chunk
  nilfs2: split nilfs_unlink as nilfs_do_unlink and nilfs_unlink
  nilfs2: delete redundant mark_inode_dirty
  nilfs2: expand inode_inc_link_count and inode_dec_link_count
  nilfs2: delete mark_inode_dirty from nilfs_set_link
  nilfs2: delete mark_inode_dirty in nilfs_new_inode
  nilfs2: add norecovery mount option
  nilfs2: add helper to get if volume is in a valid state
  nilfs2: move recovery completion into load_nilfs function
  nilfs2: apply readahead for recovery on mount
  nilfs2: clean up get/put function of a segment usage
  ...
2009-12-11 11:49:18 -08:00
Linus Torvalds 4515c3069d Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits)
  ext4: Fix potential fiemap deadlock (mmap_sem vs. i_data_sem)
  ext4: Do not override ext2 or ext3 if built they are built as modules
  jbd2: Export jbd2_log_start_commit to fix ext4 build
  ext4: Fix insufficient checks in EXT4_IOC_MOVE_EXT
  ext4: Wait for proper transaction commit on fsync
  ext4: fix incorrect block reservation on quota transfer.
  ext4: quota macros cleanup
  ext4: ext4_get_reserved_space() must return bytes instead of blocks
  ext4: remove blocks from inode prealloc list on failure
  ext4: wait for log to commit when umounting
  ext4: Avoid data / filesystem corruption when write fails to copy data
  ext4: Use ext4 file system driver for ext2/ext3 file system mounts
  ext4: Return the PTR_ERR of the correct pointer in setup_new_group_blocks()
  jbd2: Add ENOMEM checking in and for jbd2_journal_write_metadata_buffer()
  ext4: remove unused parameter wbc from __ext4_journalled_writepage()
  ext4: remove encountered_congestion trace
  ext4: move_extent_per_page() cleanup
  ext4: initialize moved_len before calling ext4_move_extents()
  ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT
  ext4: use ext4_data_block_valid() in ext4_free_blocks()
  ...
2009-12-10 09:33:29 -08:00
Eric Sandeen dee1d3b627 ext3: make "norecovery" an alias for "noload"
Users on the list recently complained about differences across
filesystems w.r.t. how to mount without a journal replay.

In the discussion it was noted that xfs's "norecovery" option is
perhaps more descriptively accurate than "noload," so let's make
that an alias for ext3.

Also show this status in /proc/mounts

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-12-10 15:02:52 +01:00
Christoph Hellwig 94004ed726 kill wait_on_page_writeback_range
All callers really want the more logical filemap_fdatawait_range interface,
so convert them to use it and merge wait_on_page_writeback_range into
filemap_fdatawait_range.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-12-10 15:02:50 +01:00
Thadeu Lima de Souza Cascardo 9f249162fb trivial: some small fixes in exofs documentation
Add exofs.txt to filesystems Documentation index and fix some typos,
identation and grammar.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2009-12-10 09:59:16 +02:00
Luis Garces-Erice e3cc2226e9 Doc: better explanation of procs_running
the description in Documentation/filesystems/proc.txt of the
procs_running entry in /proc/stat is confusing (according to that
description, it looks as if procs_running could only be a number
between 0 and the number of CPUs).

Changed it to a more accurate description in the patch attached.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-09 18:59:52 -08:00
Linus Torvalds 897e81bea1 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (35 commits)
  sched, cputime: Introduce thread_group_times()
  sched, cputime: Cleanups related to task_times()
  Revert "sched, x86: Optimize branch hint in __switch_to()"
  sched: Fix isolcpus boot option
  sched: Revert 498657a478
  sched, time: Define nsecs_to_jiffies()
  sched: Remove task_{u,s,g}time()
  sched: Introduce task_times() to replace task_{u,s}time() pair
  sched: Limit the number of scheduler debug messages
  sched.c: Call debug_show_all_locks() when dumping all tasks
  sched, x86: Optimize branch hint in __switch_to()
  sched: Optimize branch hint in context_switch()
  sched: Optimize branch hint in pick_next_task_fair()
  sched_feat_write(): Update ppos instead of file->f_pos
  sched: Sched_rt_periodic_timer vs cpu hotplug
  sched, kvm: Fix race condition involving sched_in_preempt_notifers
  sched: More generic WAKE_AFFINE vs select_idle_sibling()
  sched: Cleanup select_task_rq_fair()
  sched: Fix granularity of task_u/stime()
  sched: Fix/add missing update_rq_clock() calls
  ...
2009-12-05 15:30:49 -08:00
Linus Torvalds 6e80133f7f Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (31 commits)
  FS-Cache: Provide nop fscache_stat_d() if CONFIG_FSCACHE_STATS=n
  SLOW_WORK: Fix GFS2 to #include <linux/module.h> before using THIS_MODULE
  SLOW_WORK: Fix CIFS to pass THIS_MODULE to slow_work_register_user()
  CacheFiles: Don't log lookup/create failing with ENOBUFS
  CacheFiles: Catch an overly long wait for an old active object
  CacheFiles: Better showing of debugging information in active object problems
  CacheFiles: Mark parent directory locks as I_MUTEX_PARENT to keep lockdep happy
  CacheFiles: Handle truncate unlocking the page we're reading
  CacheFiles: Don't write a full page if there's only a partial page to cache
  FS-Cache: Actually requeue an object when requested
  FS-Cache: Start processing an object's operations on that object's death
  FS-Cache: Make sure FSCACHE_COOKIE_LOOKING_UP cleared on lookup failure
  FS-Cache: Add a retirement stat counter
  FS-Cache: Handle pages pending storage that get evicted under OOM conditions
  FS-Cache: Handle read request vs lookup, creation or other cache failure
  FS-Cache: Don't delete pending pages from the page-store tracking tree
  FS-Cache: Fix lock misorder in fscache_write_op()
  FS-Cache: The object-available state can't rely on the cookie to be available
  FS-Cache: Permit cache retrieval ops to be interrupted in the initial wait phase
  FS-Cache: Use radix tree preload correctly in tracking of pages to be stored
  ...
2009-11-30 13:33:48 -08:00
Ingo Molnar 16bc67edeb Merge branch 'sched/urgent' into sched/core
Merge reason: Pick up fixes that did not make it into .32.0

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-26 10:50:42 +01:00
J. Bruce Fields 9b8b317d58 Merge commit 'v2.6.32-rc8' into HEAD 2009-11-23 12:34:58 -05:00
Joern Engel 5db53f3e80 [LogFS] add new flash file system
This is a new flash file system. See
Documentation/filesystems/logfs.txt

Signed-off-by: Joern Engel <joern@logfs.org>
2009-11-20 20:13:39 +01:00
Linus Torvalds 931ed94430 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
  ocfs2: Trivial cleanup of jbd compatibility layer removal
  ocfs2: Refresh documentation
  ocfs2: return f_fsid info in ocfs2_statfs()
  ocfs2: duplicate inline data properly during reflink.
  ocfs2: Move ocfs2_complete_reflink to the right place.
  ocfs2: Return -EINVAL when a device is not ocfs2.
2009-11-19 20:29:05 -08:00
Ryusuke Konishi 0234576d04 nilfs2: add norecovery mount option
This adds "norecovery" mount option which disables temporal write
access to read-only mounts or snapshots during mount/recovery.
Without this option, write access will be even performed for those
types of mounts; the temporal write access is needed to mount root
file system read-only after an unclean shutdown.

This option will be helpful when user wants to prevent any write
access to the device.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Eric Sandeen <sandeen@redhat.com>
2009-11-20 10:05:52 +09:00
Jiro SEKIBA 91f1953bf3 nilfs2: Using nobarrier option instead of barrier=off
Since most of fs using nofoobar style option,
modified barrier=off option as nobarrier.

Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-11-20 10:05:47 +09:00
Eric Sandeen e3bb52ae2b ext4: make "norecovery" an alias for "noload"
Users on the linux-ext4 list recently complained about differences
across filesystems w.r.t. how to mount without a journal replay.

In the discussion it was noted that xfs's "norecovery" option is
perhaps more descriptively accurate than "noload," so let's make
that an alias for ext4.

Also show this status in /proc/mounts

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-19 14:28:50 -05:00
Eric Sandeen 5328e63531 ext4: make trim/discard optional (and off by default)
It is anticipated that when sb_issue_discard starts doing
real work on trim-capable devices, we may see issues.  Make
this mount-time optional, and default it to off until we know
that things are working out OK.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-19 14:25:42 -05:00
David Howells fee096deb4 CacheFiles: Catch an overly long wait for an old active object
Catch an overly long wait for an old, dying active object when we want to
replace it with a new one.  The probability is that all the slow-work threads
are hogged, and the delete can't get a look in.

What we do instead is:

 (1) if there's nothing in the slow work queue, we sleep until either the dying
     object has finished dying or there is something in the slow work queue
     behind which we can queue our object.

 (2) if there is something in the slow work queue, we return ETIMEDOUT to
     fscache_lookup_object(), which then puts us back on the slow work queue,
     presumably behind the deletion that we're blocked by.  We are then
     deferred for a while until we work our way back through the queue -
     without blocking a slow-work thread unnecessarily.

A backtrace similar to the following may appear in the log without this patch:

	INFO: task kslowd004:5711 blocked for more than 120 seconds.
	"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
	kslowd004     D 0000000000000000     0  5711      2 0x00000080
	 ffff88000340bb80 0000000000000046 ffff88002550d000 0000000000000000
	 ffff88002550d000 0000000000000007 ffff88000340bfd8 ffff88002550d2a8
	 000000000000ddf0 00000000000118c0 00000000000118c0 ffff88002550d2a8
	Call Trace:
	 [<ffffffff81058e21>] ? trace_hardirqs_on+0xd/0xf
	 [<ffffffffa011c4d8>] ? cachefiles_wait_bit+0x0/0xd [cachefiles]
	 [<ffffffffa011c4e1>] cachefiles_wait_bit+0x9/0xd [cachefiles]
	 [<ffffffff81353153>] __wait_on_bit+0x43/0x76
	 [<ffffffff8111ae39>] ? ext3_xattr_get+0x1ec/0x270
	 [<ffffffff813531ef>] out_of_line_wait_on_bit+0x69/0x74
	 [<ffffffffa011c4d8>] ? cachefiles_wait_bit+0x0/0xd [cachefiles]
	 [<ffffffff8104c125>] ? wake_bit_function+0x0/0x2e
	 [<ffffffffa011bc79>] cachefiles_mark_object_active+0x203/0x23b [cachefiles]
	 [<ffffffffa011c209>] cachefiles_walk_to_object+0x558/0x827 [cachefiles]
	 [<ffffffffa011a429>] cachefiles_lookup_object+0xac/0x12a [cachefiles]
	 [<ffffffffa00aa1e9>] fscache_lookup_object+0x1c7/0x214 [fscache]
	 [<ffffffffa00aafc5>] fscache_object_state_machine+0xa5/0x52d [fscache]
	 [<ffffffffa00ab4ac>] fscache_object_slow_work_execute+0x5f/0xa0 [fscache]
	 [<ffffffff81082093>] slow_work_execute+0x18f/0x2d1
	 [<ffffffff8108239a>] slow_work_thread+0x1c5/0x308
	 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34
	 [<ffffffff810821d5>] ? slow_work_thread+0x0/0x308
	 [<ffffffff8104be91>] kthread+0x7a/0x82
	 [<ffffffff8100beda>] child_rip+0xa/0x20
	 [<ffffffff8100b87c>] ? restore_args+0x0/0x30
	 [<ffffffff8104be17>] ? kthread+0x0/0x82
	 [<ffffffff8100bed0>] ? child_rip+0x0/0x20
	1 lock held by kslowd004/5711:
	 #0:  (&sb->s_type->i_mutex_key#7/1){+.+.+.}, at: [<ffffffffa011be64>] cachefiles_walk_to_object+0x1b3/0x827 [cachefiles]

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:12:05 +00:00
David Howells 60d543ca72 FS-Cache: Start processing an object's operations on that object's death
Start processing an object's operations when that object moves into the DYING
state as the object cannot be destroyed until all its outstanding operations
have completed.

Furthermore, make sure that read and allocation operations handle being woken
up on a dead object.  Such events are recorded in the Allocs.abt and
Retrvls.abt statistics as viewable through /proc/fs/fscache/stats.

The code for waiting for object activation for the read and allocation
operations is also extracted into its own function as it is much the same in
all cases, differing only in the stats incremented.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:45 +00:00
David Howells 201a15428b FS-Cache: Handle pages pending storage that get evicted under OOM conditions
Handle netfs pages that the vmscan algorithm wants to evict from the pagecache
under OOM conditions, but that are waiting for write to the cache.  Under these
conditions, vmscan calls the releasepage() function of the netfs, asking if a
page can be discarded.

The problem is typified by the following trace of a stuck process:

	kslowd005     D 0000000000000000     0  4253      2 0x00000080
	 ffff88001b14f370 0000000000000046 ffff880020d0d000 0000000000000007
	 0000000000000006 0000000000000001 ffff88001b14ffd8 ffff880020d0d2a8
	 000000000000ddf0 00000000000118c0 00000000000118c0 ffff880020d0d2a8
	Call Trace:
	 [<ffffffffa00782d8>] __fscache_wait_on_page_write+0x8b/0xa7 [fscache]
	 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34
	 [<ffffffffa0078240>] ? __fscache_check_page_write+0x63/0x70 [fscache]
	 [<ffffffffa00b671d>] nfs_fscache_release_page+0x4e/0xc4 [nfs]
	 [<ffffffffa00927f0>] nfs_release_page+0x3c/0x41 [nfs]
	 [<ffffffff810885d3>] try_to_release_page+0x32/0x3b
	 [<ffffffff81093203>] shrink_page_list+0x316/0x4ac
	 [<ffffffff8109372b>] shrink_inactive_list+0x392/0x67c
	 [<ffffffff813532fa>] ? __mutex_unlock_slowpath+0x100/0x10b
	 [<ffffffff81058df0>] ? trace_hardirqs_on_caller+0x10c/0x130
	 [<ffffffff8135330e>] ? mutex_unlock+0x9/0xb
	 [<ffffffff81093aa2>] shrink_list+0x8d/0x8f
	 [<ffffffff81093d1c>] shrink_zone+0x278/0x33c
	 [<ffffffff81052d6c>] ? ktime_get_ts+0xad/0xba
	 [<ffffffff81094b13>] try_to_free_pages+0x22e/0x392
	 [<ffffffff81091e24>] ? isolate_pages_global+0x0/0x212
	 [<ffffffff8108e743>] __alloc_pages_nodemask+0x3dc/0x5cf
	 [<ffffffff81089529>] grab_cache_page_write_begin+0x65/0xaa
	 [<ffffffff8110f8c0>] ext3_write_begin+0x78/0x1eb
	 [<ffffffff81089ec5>] generic_file_buffered_write+0x109/0x28c
	 [<ffffffff8103cb69>] ? current_fs_time+0x22/0x29
	 [<ffffffff8108a509>] __generic_file_aio_write+0x350/0x385
	 [<ffffffff8108a588>] ? generic_file_aio_write+0x4a/0xae
	 [<ffffffff8108a59e>] generic_file_aio_write+0x60/0xae
	 [<ffffffff810b2e82>] do_sync_write+0xe3/0x120
	 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34
	 [<ffffffff810b18e1>] ? __dentry_open+0x1a5/0x2b8
	 [<ffffffff810b1a76>] ? dentry_open+0x82/0x89
	 [<ffffffffa00e693c>] cachefiles_write_page+0x298/0x335 [cachefiles]
	 [<ffffffffa0077147>] fscache_write_op+0x178/0x2c2 [fscache]
	 [<ffffffffa0075656>] fscache_op_execute+0x7a/0xd1 [fscache]
	 [<ffffffff81082093>] slow_work_execute+0x18f/0x2d1
	 [<ffffffff8108239a>] slow_work_thread+0x1c5/0x308
	 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34
	 [<ffffffff810821d5>] ? slow_work_thread+0x0/0x308
	 [<ffffffff8104be91>] kthread+0x7a/0x82
	 [<ffffffff8100beda>] child_rip+0xa/0x20
	 [<ffffffff8100b87c>] ? restore_args+0x0/0x30
	 [<ffffffff8102ef83>] ? tg_shares_up+0x171/0x227
	 [<ffffffff8104be17>] ? kthread+0x0/0x82
	 [<ffffffff8100bed0>] ? child_rip+0x0/0x20

In the above backtrace, the following is happening:

 (1) A page storage operation is being executed by a slow-work thread
     (fscache_write_op()).

 (2) FS-Cache farms the operation out to the cache to perform
     (cachefiles_write_page()).

 (3) CacheFiles is then calling Ext3 to perform the actual write, using Ext3's
     standard write (do_sync_write()) under KERNEL_DS directly from the netfs
     page.

 (4) However, for Ext3 to perform the write, it must allocate some memory, in
     particular, it must allocate at least one page cache page into which it
     can copy the data from the netfs page.

 (5) Under OOM conditions, the memory allocator can't immediately come up with
     a page, so it uses vmscan to find something to discard
     (try_to_free_pages()).

 (6) vmscan finds a clean netfs page it might be able to discard (possibly the
     one it's trying to write out).

 (7) The netfs is called to throw the page away (nfs_release_page()) - but it's
     called with __GFP_WAIT, so the netfs decides to wait for the store to
     complete (__fscache_wait_on_page_write()).

 (8) This blocks a slow-work processing thread - possibly against itself.

The system ends up stuck because it can't write out any netfs pages to the
cache without allocating more memory.

To avoid this, we make FS-Cache cancel some writes that aren't in the middle of
actually being performed.  This means that some data won't make it into the
cache this time.  To support this, a new FS-Cache function is added
fscache_maybe_release_page() that replaces what the netfs releasepage()
functions used to do with respect to the cache.

The decisions fscache_maybe_release_page() makes are counted and displayed
through /proc/fs/fscache/stats on a line labelled "VmScan".  There are four
counters provided: "nos=N" - pages that weren't pending storage; "gon=N" -
pages that were pending storage when we first looked, but weren't by the time
we got the object lock; "bsy=N" - pages that we ignored as they were actively
being written when we looked; and "can=N" - pages that we cancelled the storage
of.

What I'd really like to do is alter the behaviour of the cancellation
heuristics, depending on how necessary it is to expel pages.  If there are
plenty of other pages that aren't waiting to be written to the cache that
could be ejected first, then it would be nice to hold up on immediate
cancellation of cache writes - but I don't see a way of doing that.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:35 +00:00
David Howells e3d4d28b1c FS-Cache: Handle read request vs lookup, creation or other cache failure
FS-Cache doesn't correctly handle the netfs requesting a read from the cache
on an object that failed or was withdrawn by the cache.  A trace similar to
the following might be seen:

	CacheFiles: Lookup failed error -105
	[exe   ] unexpected submission OP165afe [OBJ6cac OBJECT_LC_DYING]
	[exe   ] objstate=OBJECT_LC_DYING [OBJECT_LC_DYING]
	[exe   ] objflags=0
	[exe   ] objevent=9 [fffffffffffffffb]
	[exe   ] ops=0 inp=0 exc=0
	Pid: 6970, comm: exe Not tainted 2.6.32-rc6-cachefs #50
	Call Trace:
	 [<ffffffffa0076477>] fscache_submit_op+0x3ff/0x45a [fscache]
	 [<ffffffffa0077997>] __fscache_read_or_alloc_pages+0x187/0x3c4 [fscache]
	 [<ffffffffa00b6480>] ? nfs_readpage_from_fscache_complete+0x0/0x66 [nfs]
	 [<ffffffffa00b6388>] __nfs_readpages_from_fscache+0x7e/0x176 [nfs]
	 [<ffffffff8108e483>] ? __alloc_pages_nodemask+0x11c/0x5cf
	 [<ffffffffa009d796>] nfs_readpages+0x114/0x1d7 [nfs]
	 [<ffffffff81090314>] __do_page_cache_readahead+0x15f/0x1ec
	 [<ffffffff81090228>] ? __do_page_cache_readahead+0x73/0x1ec
	 [<ffffffff810903bd>] ra_submit+0x1c/0x20
	 [<ffffffff810906bb>] ondemand_readahead+0x227/0x23a
	 [<ffffffff81090762>] page_cache_sync_readahead+0x17/0x19
	 [<ffffffff8108a99e>] generic_file_aio_read+0x236/0x5a0
	 [<ffffffffa00937bd>] nfs_file_read+0xe4/0xf3 [nfs]
	 [<ffffffff810b2fa2>] do_sync_read+0xe3/0x120
	 [<ffffffff81354cc3>] ? _spin_unlock_irq+0x2b/0x31
	 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34
	 [<ffffffff811848e5>] ? selinux_file_permission+0x5d/0x10f
	 [<ffffffff81352bdb>] ? thread_return+0x3e/0x101
	 [<ffffffff8117d7b0>] ? security_file_permission+0x11/0x13
	 [<ffffffff810b3b06>] vfs_read+0xaa/0x16f
	 [<ffffffff81058df0>] ? trace_hardirqs_on_caller+0x10c/0x130
	 [<ffffffff810b3c84>] sys_read+0x45/0x6c
	 [<ffffffff8100ae2b>] system_call_fastpath+0x16/0x1b

The object state might also be OBJECT_DYING or OBJECT_WITHDRAWING.

This should be handled by simply rejecting the new operation with ENOBUFS.
There's no need to log an error for it.  Events of this type now appear in the
stats file under Ops:rej.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:32 +00:00
David Howells 1bccf513ac FS-Cache: Fix lock misorder in fscache_write_op()
FS-Cache has two structs internally for keeping track of the internal state of
a cached file: the fscache_cookie struct, which represents the netfs's state,
and fscache_object struct, which represents the cache's state.  Each has a
pointer that points to the other (when both are in existence), and each has a
spinlock for pointer maintenance.

Since netfs operations approach these structures from the cookie side, they get
the cookie lock first, then the object lock.  Cache operations, on the other
hand, approach from the object side, and get the object lock first.  It is not
then permitted for a cache operation to get the cookie lock whilst it is
holding the object lock lest deadlock occur; instead, it must do one of two
things:

 (1) increment the cookie usage counter, drop the object lock and then get both
     locks in order, or

 (2) simply hold the object lock as certain parts of the cookie may not be
     altered whilst the object lock is held.

It is also not permitted to follow either pointer without holding the lock at
the end you start with.  To break the pointers between the cookie and the
object, both locks must be held.

fscache_write_op(), however, violates the locking rules: It attempts to get the
cookie lock without (a) checking that the cookie pointer is a valid pointer,
and (b) holding the object lock to protect the cookie pointer whilst it follows
it.  This is so that it can access the pending page store tree without
interference from __fscache_write_page().

This is fixed by splitting the cookie lock, such that the page store tracking
tree is protected by its own lock, and checking that the cookie pointer is
non-NULL before we attempt to follow it whilst holding the object lock.

The new lock is subordinate to both the cookie lock and the object lock, and so
should be taken after those.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:25 +00:00
David Howells 5753c44188 FS-Cache: Permit cache retrieval ops to be interrupted in the initial wait phase
Permit the operations to retrieve data from the cache or to allocate space in
the cache for future writes to be interrupted whilst they're waiting for
permission for the operation to proceed.  Typically this wait occurs whilst the
cache object is being looked up on disk in the background.

If an interruption occurs, and the operation has not yet been given the
go-ahead to run, the operation is dequeued and cancelled, and control returns
to the read operation of the netfs routine with none of the requested pages
having been read or in any way marked as known by the cache.

This means that the initial wait is done interruptibly rather than
uninterruptibly.

In addition, extra stats values are made available to show the number of ops
cancelled and the number of cache space allocations interrupted.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:19 +00:00
David Howells 52bd75fdb1 FS-Cache: Add counters for entry/exit to/from cache operation functions
Count entries to and exits from cache operation table functions.  Maintain
these as a single counter that's added to or removed from as appropriate.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:08 +00:00
David Howells 4fbf4291aa FS-Cache: Allow the current state of all objects to be dumped
Allow the current state of all fscache objects to be dumped by doing:

	cat /proc/fs/fscache/objects

By default, all objects and all fields will be shown.  This can be restricted
by adding a suitable key to one of the caller's keyrings (such as the session
keyring):

	keyctl add user fscache:objlist "<restrictions>" @s

The <restrictions> are:

	K	Show hexdump of object key (don't show if not given)
	A	Show hexdump of object aux data (don't show if not given)

And paired restrictions:

	C	Show objects that have a cookie
	c	Show objects that don't have a cookie
	B	Show objects that are busy
	b	Show objects that aren't busy
	W	Show objects that have pending writes
	w	Show objects that don't have pending writes
	R	Show objects that have outstanding reads
	r	Show objects that don't have outstanding reads
	S	Show objects that have slow work queued
	s	Show objects that don't have slow work queued

If neither side of a restriction pair is given, then both are implied.  For
example:

	keyctl add user fscache:objlist KB @s

shows objects that are busy, and lists their object keys, but does not dump
their auxiliary data.  It also implies "CcWwRrSs", but as 'B' is given, 'b' is
not implied.

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:04 +00:00
Sunil Mushran 7ab8f5244d ocfs2: Refresh documentation
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-11-13 15:45:01 -08:00
J. Bruce Fields ea4878a24d nfs: move more to Documentation/filesystems/nfs
Oops: I missed two files in the first commit that created this
directory.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-11-06 14:01:02 -05:00
Linus Torvalds d4da6c9ccf Revert "ext4: Remove journal_checksum mount option and enable it by default"
This reverts commit d0646f7b63, as
requested by Eric Sandeen.

It can basically cause an ext4 filesystem to miss recovery (and thus get
mounted with errors) if the journal checksum does not match.

Quoth Eric:

   "My hand-wavy hunch about what is happening is that we're finding a
    bad checksum on the last partially-written transaction, which is
    not surprising, but if we have a wrapped log and we're doing the
    initial scan for head/tail, and we abort scanning on that bad
    checksum, then we are essentially running an unrecovered filesystem.

    But that's hand-wavy and I need to go look at the code.

    We lived without journal checksums on by default until now, and at
    this point they're doing more harm than good, so we should revert
    the default-changing commit until we can fix it and do some good
    power-fail testing with the fixes in place."

See

	http://bugzilla.kernel.org/show_bug.cgi?id=14354

for all the gory details.

Requested-by: Eric Sandeen <sandeen@redhat.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Alexey Fisher <bug-track@fisher-privat.net>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Mathias Burén <mathias.buren@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-02 10:15:27 -08:00
J. Bruce Fields dc7a08166f nfs: new subdir Documentation/filesystems/nfs
We're adding enough nfs documentation that it may as well have its own
subdirectory.

Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-10-27 19:34:04 -04:00
J. Bruce Fields e343eb0d60 Merge commit 'v2.6.32-rc5' into for-2.6.33 2009-10-27 18:45:17 -04:00
Ryota Ozaki ce0e7b28fb sched, cpuacct: Fix niced guest time accounting
CPU time of a guest is always accounted in 'user' time
without concern for the nice value of its counterpart
process although the guest is scheduled under the nice
value.

This patch fixes the defect and accounts cpu time of
a niced guest in 'nice' time as same as a niced process.

And also the patch adds 'guest_nice' to cpuacct. The
value provides niced guest cpu time which is like 'nice'
to 'user'.

The original discussions can be found here:

  http://www.mail-archive.com/kvm@vger.kernel.org/msg23982.html
  http://www.mail-archive.com/kvm@vger.kernel.org/msg23860.html

Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Acked-by: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1256314810-7897-1-git-send-email-ozaki.ryota@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-25 17:31:30 +01:00
Jan Kara 6dbce52182 ext3: Update documentation about ext3 quota mount options
Signed-off-by: Jan Kara <jack@suse.cz>
2009-10-13 00:06:43 +02:00
Sage Weil 7ad920b504 ceph: documentation
Mount options, syntax.

Signed-off-by: Sage Weil <sage@newdream.net>
2009-10-06 11:31:05 -07:00
Linus Torvalds 9f44fdc518 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Fix time encoding with extra epoch bits
  ext4: Add a stub for mpage_da_data in the trace header
  jbd2: Use tracepoints for history file
  ext4: Use tracepoints for mb_history trace file
  ext4, jbd2: Drop unneeded printks at mount and unmount time
  ext4: Handle nested ext4_journal_start/stop calls without a journal
  ext4: Make sure ext4_dirty_inode() updates the inode in no journal mode
  ext4: Avoid updating the inode table bh twice in no journal mode
  ext4: EXT4_IOC_MOVE_EXT: Check for different original and donor inodes first
  ext4: async direct IO for holes and fallocate support
  ext4: Use end_io callback to avoid direct I/O fallback to buffered I/O
  ext4: Split uninitialized extents for direct I/O
  ext4: release reserved quota when block reservation for delalloc retry
  ext4: Adjust ext4_da_writepages() to write out larger contiguous chunks
  ext4: Fix hueristic which avoids group preallocation for closed files
  ext4: Use ext4_msg() for ext4_da_writepage() errors
  ext4: Update documentation about quota mount options
2009-09-30 09:32:30 -07:00
Linus Torvalds 4c8f1cb266 Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
  fat: Check s_dirt in fat_sync_fs()
  vfat: change the default from shortname=lower to shortname=mixed
  fat/nls: Fix handling of utf8 invalid char
2009-09-30 09:31:14 -07:00
Theodore Ts'o 296c355cd6 ext4: Use tracepoints for mb_history trace file
The /proc/fs/ext4/<dev>/mb_history was maintained manually, and had a
number of problems: it required a largish amount of memory to be
allocated for each ext4 filesystem, and the s_mb_history_lock
introduced a CPU contention problem.  

By ripping out the mb_history code and replacing it with ftrace
tracepoints, and we get more functionality: timestamps, event
filtering, the ability to correlate mballoc history with other ext4
tracepoints, etc.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-30 00:32:42 -04:00
Andy Adamson ddc04fd4d5 nfsd41: use sv_max_mesg for forechannel max sizes
ca_maxresponsesize and ca_maxrequest size include the RPC header.

sv_max_mesg is sv_max_payolad plus a page for overhead and is used in
svc_init_buffer to allocate server buffer space for both the request and reply.
Note that this means we can service an RPC compound that requires
ca_maxrequestsize (MAXWRITE) or ca_max_responsesize (MAXREAD) but that we do
not support an RPC compound that requires both ca_maxrequestsize and
ca_maxresponsesize.

Signed-off-by: Andy Adamson <andros@netapp.com>
[bfields@citi.umich.edu: more documentation updates]
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-28 12:40:15 -04:00
J. Bruce Fields 03d6a74b5f nfsd: fix Documentation typo
Caught by Benny, thanks!

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-28 12:07:52 -04:00
Jan Kara 8365388827 ext4: Update documentation about quota mount options
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-29 15:59:34 -04:00
Linus Torvalds db16826367 Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits)
  HWPOISON: Enable error_remove_page on btrfs
  HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
  HWPOISON: Add madvise() based injector for hardware poisoned pages v4
  HWPOISON: Enable error_remove_page for NFS
  HWPOISON: Enable .remove_error_page for migration aware file systems
  HWPOISON: The high level memory error handler in the VM v7
  HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
  HWPOISON: shmem: call set_page_dirty() with locked page
  HWPOISON: Define a new error_remove_page address space op for async truncation
  HWPOISON: Add invalidate_inode_page
  HWPOISON: Refactor truncate to allow direct truncating of page v2
  HWPOISON: check and isolate corrupted free pages v2
  HWPOISON: Handle hardware poisoned pages in try_to_unmap
  HWPOISON: Use bitmask/action code for try_to_unmap behaviour
  HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2
  HWPOISON: Add poison check to page fault handling
  HWPOISON: Add basic support for poisoned pages in fault handler v3
  HWPOISON: Add new SIGBUS error codes for hardware poison signals
  HWPOISON: Add support for poison swap entries v2
  HWPOISON: Export some rmap vma locking to outside world
  ...
2009-09-24 07:53:22 -07:00
Peng Tao 16c01b20ae doc/filesystems: more mount cleanups
Documentation/filesystems/sharedsubtree.txt needs updating because the
mount command in util-linux package is well aware of shared subtree
features now.  The patch also fixes two typos in sharedsubtree.txt.

Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:57 -07:00
Randy Dunlap 0288b95b43 doc/filesystems: remove smount program
mount(8) handles shared subtrees just fine, so remove the smount program
from Documentation/filesystems/sharedsubtree.txt.

Fix annoying "Lets" -> "Let's".
Insert space between '#' prompt and "mount" command.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:57 -07:00
Abhishek Kulkarni f4edeeb393 9p: Update documentation to add fscache related bits
Update the documentation to describe FS-Cache related
caching parameters. This patch also updates the pointers
to 9p-related papers and adds pointer to the Wiki.

Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2009-09-23 13:03:46 -05:00
Bartlomiej Zolnierkiewicz 1b83df308f ncpfs: remove dead URL from documentation
Noticed-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:42 -07:00
Stefani Seibold d899bf7b55 procfs: provide stack information for threads
A patch to give a better overview of the userland application stack usage,
especially for embedded linux.

Currently you are only able to dump the main process/thread stack usage
which is showed in /proc/pid/status by the "VmStk" Value.  But you get no
information about the consumed stack memory of the the threads.

There is an enhancement in the /proc/<pid>/{task/*,}/*maps and which marks
the vm mapping where the thread stack pointer reside with "[thread stack
xxxxxxxx]".  xxxxxxxx is the maximum size of stack.  This is a value
information, because libpthread doesn't set the start of the stack to the
top of the mapped area, depending of the pthread usage.

A sample output of /proc/<pid>/task/<tid>/maps looks like:

08048000-08049000 r-xp 00000000 03:00 8312       /opt/z
08049000-0804a000 rw-p 00001000 03:00 8312       /opt/z
0804a000-0806b000 rw-p 00000000 00:00 0          [heap]
a7d12000-a7d13000 ---p 00000000 00:00 0
a7d13000-a7f13000 rw-p 00000000 00:00 0          [thread stack: 001ff4b4]
a7f13000-a7f14000 ---p 00000000 00:00 0
a7f14000-a7f36000 rw-p 00000000 00:00 0
a7f36000-a8069000 r-xp 00000000 03:00 4222       /lib/libc.so.6
a8069000-a806b000 r--p 00133000 03:00 4222       /lib/libc.so.6
a806b000-a806c000 rw-p 00135000 03:00 4222       /lib/libc.so.6
a806c000-a806f000 rw-p 00000000 00:00 0
a806f000-a8083000 r-xp 00000000 03:00 14462      /lib/libpthread.so.0
a8083000-a8084000 r--p 00013000 03:00 14462      /lib/libpthread.so.0
a8084000-a8085000 rw-p 00014000 03:00 14462      /lib/libpthread.so.0
a8085000-a8088000 rw-p 00000000 00:00 0
a8088000-a80a4000 r-xp 00000000 03:00 8317       /lib/ld-linux.so.2
a80a4000-a80a5000 r--p 0001b000 03:00 8317       /lib/ld-linux.so.2
a80a5000-a80a6000 rw-p 0001c000 03:00 8317       /lib/ld-linux.so.2
afaf5000-afb0a000 rw-p 00000000 00:00 0          [stack]
ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]

Also there is a new entry "stack usage" in /proc/<pid>/{task/*,}/status
which will you give the current stack usage in kb.

A sample output of /proc/self/status looks like:

Name:	cat
State:	R (running)
Tgid:	507
Pid:	507
.
.
.
CapBnd:	fffffffffffffeff
voluntary_ctxt_switches:	0
nonvoluntary_ctxt_switches:	0
Stack usage:	12 kB

I also fixed stack base address in /proc/<pid>/{task/*,}/stat to the base
address of the associated thread stack and not the one of the main
process.  This makes more sense.

[akpm@linux-foundation.org: fs/proc/array.c now needs walk_page_range()]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:41 -07:00
Linus Torvalds a87e84b5cd Merge branch 'for-2.6.32' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.32' of git://linux-nfs.org/~bfields/linux: (68 commits)
  nfsd4: nfsv4 clients should cross mountpoints
  nfsd: revise 4.1 status documentation
  sunrpc/cache: avoid variable over-loading in cache_defer_req
  sunrpc/cache: use list_del_init for the list_head entries in cache_deferred_req
  nfsd: return success for non-NFS4 nfs4_state_start
  nfsd41: Refactor create_client()
  nfsd41: modify nfsd4.1 backchannel to use new xprt class
  nfsd41: Backchannel: Implement cb_recall over NFSv4.1
  nfsd41: Backchannel: cb_sequence callback
  nfsd41: Backchannel: Setup sequence information
  nfsd41: Backchannel: Server backchannel RPC wait queue
  nfsd41: Backchannel: Add sequence arguments to callback RPC arguments
  nfsd41: Backchannel: callback infrastructure
  nfsd4: use common rpc_cred for all callbacks
  nfsd4: allow nfs4 state startup to fail
  SUNRPC: Defer the auth_gss upcall when the RPC call is asynchronous
  nfsd4: fix null dereference creating nfsv4 callback client
  nfsd4: fix whitespace in NFSPROC4_CLNT_CB_NULL definition
  nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel
  sunrpc/cache: simplify cache_fresh_locked and cache_fresh_unlocked.
  ...
2009-09-22 07:54:33 -07:00
Linus Torvalds 342ff1a1b5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  trivial: fix typo in aic7xxx comment
  trivial: fix comment typo in drivers/ata/pata_hpt37x.c
  trivial: typo in kernel-parameters.txt
  trivial: fix typo in tracing documentation
  trivial: add __init/__exit macros in drivers/gpio/bt8xxgpio.c
  trivial: add __init macro/ fix of __exit macro location in ipmi_poweroff.c
  trivial: remove unnecessary semicolons
  trivial: Fix duplicated word "options" in comment
  trivial: kbuild: remove extraneous blank line after declaration of usage()
  trivial: improve help text for mm debug config options
  trivial: doc: hpfall: accept disk device to unload as argument
  trivial: doc: hpfall: reduce risk that hpfall can do harm
  trivial: SubmittingPatches: Fix reference to renumbered step
  trivial: fix typos "man[ae]g?ment" -> "management"
  trivial: media/video/cx88: add __init/__exit macros to cx88 drivers
  trivial: fix typo in CONFIG_DEBUG_FS in gcov doc
  trivial: fix missing printk space in amd_k7_smp_check
  trivial: fix typo s/ketymap/keymap/ in comment
  trivial: fix typo "to to" in multiple files
  trivial: fix typos in comments s/DGBU/DBGU/
  ...
2009-09-22 07:51:45 -07:00
KOSAKI Motohiro 495789a51a oom: make oom_score to per-process value
oom-killer kills a process, not task.  Then oom_score should be calculated
as per-process too.  it makes consistency more and makes speed up
select_bad_process().

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:39 -07:00
Moussa A. Ba 398499d5f3 pagemap clear_refs: modify to specify anon or mapped vma clearing
The patch makes the clear_refs more versatile in adding the option to
select anonymous pages or file backed pages for clearing.  This addition
has a measurable impact on user space application performance as it
decreases the number of pagewalks in scenarios where one is only
interested in a specific type of page (anonymous or file mapped).

The patch adds anonymous and file backed filters to the clear_refs interface.

echo 1 > /proc/PID/clear_refs resets the bits on all pages
echo 2 > /proc/PID/clear_refs resets the bits on anonymous pages only
echo 3 > /proc/PID/clear_refs resets the bits on file backed pages only

Any other value is ignored

Signed-off-by: Moussa A. Ba <moussa.a.ba@gmail.com>
Signed-off-by: Jared E. Hulbert <jaredeh@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:33 -07:00
Eric Dumazet c574358e8b proc: document `guest' column in /proc/stat
We added a new column in cpuX lines of /proc/stat, to show the amount of
time spent by a cpu servicing a guest, without updating
Documentation/filesystems/proc.txt

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
J. Bruce Fields 285a0f00c2 nfsd: revise 4.1 status documentation
Some small updates, a caveat about the minorversion control interface,
and an attempt to put missing features in context.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-21 11:13:45 -04:00
Anand Gadiyar 411c940385 trivial: fix typo "for for" in multiple files
trivial: fix typo "for for" in multiple files

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:54 +02:00
Jan Kara 1358870dea ext4: Update documentation about quota mount options
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-18 12:22:29 -04:00
Andi Kleen 2571873621 HWPOISON: Define a new error_remove_page address space op for async truncation
Truncating metadata pages is not safe right now before
we haven't audited all file systems.

To enable truncation only for data address space define
a new address_space callback error_remove_page.

This is used for memory_failure.c memory error handling.

This can be then set to truncate_inode_page()

This patch just defines the new operation and adds documentation.

Callers and users come in followon patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-09-16 11:50:13 +02:00
Linus Torvalds a9bbd210a4 Merge branch 'docs-next' of git://git.lwn.net/linux-2.6
* 'docs-next' of git://git.lwn.net/linux-2.6:
  Document the flex_array library.
  Doc: seq_file.txt fix wrong dd command example.
2009-09-14 17:52:32 -07:00
Linus Torvalds 33f1de6931 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
  GFS2: Whitespace fixes
  GFS2: Remove unused sysfs file
  GFS2: Be extra careful about deallocating inodes
  GFS2: Remove no_formal_ino generating code
  GFS2: Rename eattr.[ch] as xattr.[ch]
  GFS2: Clean up of extended attribute support
  GFS2: Add explanation of extended attr on-disk format
  GFS2: Add "-o errors=panic|withdraw" mount options
  GFS2: jumping to wrong label?
  GFS2: free disk inode which is deleted by remote node -V2
  GFS2: Add a document explaining GFS2's uevents
  GFS2: Add sysfs link to device
  GFS2: Replace assertion with proper error handling
  GFS2: Improve error handling in inode allocation
  GFS2: Add some more info to uevents
  GFS2: Add online uevent to GFS2
2009-09-14 14:35:56 -07:00
Trond Myklebust ab3bbaa8b2 Merge branch 'nfs-for-2.6.32' 2009-09-11 14:59:37 -04:00
Jesper Dangaard Brouer e8188807b7 Doc: seq_file.txt fix wrong dd command example.
Small error in the "dd" command example, "out=" should be "of=".

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-09-10 14:33:35 -06:00
Theodore Ts'o d0646f7b63 ext4: Remove journal_checksum mount option and enable it by default
There's no real cost for the journal checksum feature, and we should
make sure it is enabled all the time.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-05 12:50:43 -04:00
Linus Torvalds cf481442f2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  9p: update documentation pointers
  9p: remove unnecessary v9fses->options which duplicates the mount string
  net/9p: insulate the client against an invalid error code sent by a 9p server
  9p: Add missing cast for the error return value in v9fs_get_inode
  9p: Remove redundant inode uid/gid assignment
  9p: Fix possible regressions when ->get_sb fails.
  9p: Fix v9fs show_options
  9p: Fix possible memleak in v9fs_inode_from fid.
  9p: minor comment fixes
  9p: Fix possible inode leak in v9fs_get_inode.
  9p: Check for error in return value of v9fs_fid_add
2009-08-27 12:24:08 -07:00
Trond Myklebust e571cbf1a4 NFS: Add a dns resolver for use with NFSv4 referrals and migration
The NFSv4 and NFSv4.1 protocols both allow for the redirection of a client
from one server to another in order to support filesystem migration and
replication. For full protocol support, we need to add the ability to
convert a DNS host name into an IP address that we can feed to the RPC
client.

We'll reuse the sunrpc cache, now that it has been converted to work with
rpc_pipefs.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-19 18:22:15 -04:00
Anton Blanchard 0dc9aa845c AFS: Documentation updates
Fix some issues with the AFS documentation, found when testing AFS on ppc64:

- Update AFS features: reading/writing, local caching
- Typo in kafs sysfs debug file
- Use modprobe instead of insmod in example
- Update IPs for grand.central.org

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-19 10:40:13 -07:00
KOSAKI Motohiro 0753ba01e1 mm: revert "oom: move oom_adj value"
The commit 2ff05b2b (oom: move oom_adj value) moveed the oom_adj value to
the mm_struct.  It was a very good first step for sanitize OOM.

However Paul Menage reported the commit makes regression to his job
scheduler.  Current OOM logic can kill OOM_DISABLED process.

Why? His program has the code of similar to the following.

	...
	set_oom_adj(OOM_DISABLE); /* The job scheduler never killed by oom */
	...
	if (vfork() == 0) {
		set_oom_adj(0); /* Invoked child can be killed */
		execve("foo-bar-cmd");
	}
	....

vfork() parent and child are shared the same mm_struct.  then above
set_oom_adj(0) doesn't only change oom_adj for vfork() child, it's also
change oom_adj for vfork() parent.  Then, vfork() parent (job scheduler)
lost OOM immune and it was killed.

Actually, fork-setting-exec idiom is very frequently used in userland program.
We must not break this assumption.

Then, this patch revert commit 2ff05b2b and related commit.

Reverted commit list
---------------------
- commit 2ff05b2b4e (oom: move oom_adj value from task_struct to mm_struct)
- commit 4d8b9135c3 (oom: avoid unnecessary mm locking and scanning for OOM_DISABLE)
- commit 8123681022 (oom: only oom kill exiting tasks with attached memory)
- commit 933b787b57 (mm: copy over oom_adj value at fork time)

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-18 16:31:13 -07:00
Eric Van Hensbergen 7815f4be40 9p: update documentation pointers
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2009-08-17 16:49:44 -05:00
Steven Whitehouse 0aa8744584 GFS2: Add a document explaining GFS2's uevents
This will be essential reading for anybody who wants to
understand how GFS2 interacts with the userland gfs_controld,
and the details of recovery.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2009-08-17 11:11:41 +01:00
Paul Wise 955234755c vfat: change the default from shortname=lower to shortname=mixed
Because, with "shortname=lower", copying one FAT filesystem tree to
another FAT filesystem tree using Linux results in semantically
different filesystems. (E.g.: Filenames which were once "all
uppercase" are now "all lowercase").

So, this changes the default of "shortname=lower" to "shortname=mixed".

Signed-off-by: Paul Wise <pabs3@bonedaddy.net>
[change fat_show_options()]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2009-08-01 21:35:25 +09:00
Lucian Adrian Grijincu a39ea210ec driver core: documentation: make it clear that sysfs is optional
The original text suggested that sysfs is mandatory and always
compiled in the kernel.

Signed-off-by: Lucian Adrian Grijincu <lgrijincu@ixiacom.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-28 13:45:23 -07:00
Christoph Hellwig 7e325d3a6b update Documentation/filesystems/Locking
The rules for locking in many superblock operations has changed
significantly, so update the documentation for it.  Also correct some
older updates and ommissions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24 08:15:25 -04:00
Linus Torvalds 7e0338c0de Merge branch 'for-2.6.31' of git://fieldses.org/git/linux-nfsd
* 'for-2.6.31' of git://fieldses.org/git/linux-nfsd: (60 commits)
  SUNRPC: Fix the TCP server's send buffer accounting
  nfsd41: Backchannel: minorversion support for the back channel
  nfsd41: Backchannel: cleanup nfs4.0 callback encode routines
  nfsd41: Remove ip address collision detection case
  nfsd: optimise the starting of zero threads when none are running.
  nfsd: don't take nfsd_mutex twice when setting number of threads.
  nfsd41: sanity check client drc maxreqs
  nfsd41: move channel attributes from nfsd4_session to a nfsd4_channel_attr struct
  NFS: kill off complicated macro 'PROC'
  sunrpc: potential memory leak in function rdma_read_xdr
  nfsd: minor nfsd_vfs_write cleanup
  nfsd: Pull write-gathering code out of nfsd_vfs_write
  nfsd: track last inode only in use_wgather case
  sunrpc: align cache_clean work's timer
  nfsd: Use write gathering only with NFSv2
  NFSv4: kill off complicated macro 'PROC'
  NFSv4: do exact check about attribute specified
  knfsd: remove unreported filehandle stats counters
  knfsd: fix reply cache memory corruption
  knfsd: reply cache cleanups
  ...
2009-06-22 12:55:50 -07:00
Linus Torvalds 0732f87761 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: clean up jbd2_journal_try_to_free_buffers()
  ext4: Don't update ctime for non-extent-mapped inodes
  ext4: Fix up whitespace issues in fs/ext4/inode.c
  ext4: Fix 64-bit block type problem on 32-bit platforms
  ext4: teach the inode allocator to use a goal inode number
  ext4: Use a hash of the topdir directory name for the Orlov parent group
  ext4: document the "abort" mount option
  ext4: move the abort flag from s_mount_opts to s_mount_flags
  ext4: update the s_last_mounted field in the superblock
  ext4: change s_mount_opt to be an unsigned int
  ext4: online defrag -- Add EXT4_IOC_MOVE_EXT ioctl
  ext4: avoid unnecessary spinlock in critical POSIX ACL path
  ext3: avoid unnecessary spinlock in critical POSIX ACL path
  ext4: convert instrumentation from markers to tracepoints
  jbd2: convert instrumentation from markers to tracepoints
2009-06-18 14:07:46 -07:00
Jan Kara 52b680c812 isofs: let mode and dmode mount options override rock ridge mode setting
So far, permissions set via 'mode' and/or 'dmode' mount options were
effective only if the medium had no rock ridge extensions (or was mounted
without them).  Add 'overriderockmode' mount option to indicate that these
options should override permissions set in rock ridge extensions.  Maybe
this should be default but the current behavior is there since mount
options were created so I think we should not change how they behave.

Cc: <Hans-Joachim.Baader@cjt.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:45 -07:00
Michael Shields ce05b2a9db Doc fix: ext2 can only have 32,000 subdirs, not 32,768
ext2.txt says that dirs can have 32,768 subdirs, but the actual value of
EXT2_LINK_MAX is 32000.

ext3 is the same, but the doc does not mention it.  One of ext4's features
is to "fix 32000 subdirectory limit".

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:44 -07:00
Stefani Seibold 349888ee7b proc.txt: update kernel filesystem/proc.txt documentation
An update for the "Process-Specific Subdirectories" section to reflect the
changes till kernel 2.6.30.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:41 -07:00
Keika Kobayashi d3d64df21d proc: export statistics for softirq to /proc
Export statistics for softirq in /proc/softirqs and /proc/stat.

1. /proc/softirqs
Implement /proc/softirqs which shows the number of softirq
for each CPU like /proc/interrupts.

2. /proc/stat
Add the "softirq" line to /proc/stat.
This line shows the number of softirq for all cpu.
The first column is the total of all softirqs and
each subsequent column is the total for particular softirq.

[kosaki.motohiro@jp.fujitsu.com: remove redundant for_each_possible_cpu() loop]
Signed-off-by: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Reviewed-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:41 -07:00
Linus Torvalds feb72ce827 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  get rid of BKL in fs/sysv
  get rid of BKL in fs/minix
  get rid of BKL in fs/efs
  befs ->pust_super() doesn't need BKL
  Cleanup of adfs headers
  9P doesn't need BKL in ->umount_begin()
  fuse doesn't need BKL in ->umount_begin()
  No instance of ->bmap() needs BKL
  remove unlock_kernel() left accidentally
  ext4: avoid unnecessary spinlock in critical POSIX ACL path
  ext3: avoid unnecessary spinlock in critical POSIX ACL path
2009-06-17 08:46:57 -07:00
Al Viro fe36adf47e No instance of ->bmap() needs BKL
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-17 00:36:35 -04:00
Linus Torvalds 517d08699b Merge branch 'akpm'
* akpm: (182 commits)
  fbdev: bf54x-lq043fb: use kzalloc over kmalloc/memset
  fbdev: *bfin*: fix __dev{init,exit} markings
  fbdev: *bfin*: drop unnecessary calls to memset
  fbdev: bfin-t350mcqb-fb: drop unused local variables
  fbdev: blackfin has __raw I/O accessors, so use them in fb.h
  fbdev: s1d13xxxfb: add accelerated bitblt functions
  tcx: use standard fields for framebuffer physical address and length
  fbdev: add support for handoff from firmware to hw framebuffers
  intelfb: fix a bug when changing video timing
  fbdev: use framebuffer_release() for freeing fb_info structures
  radeon: P2G2CLK_ALWAYS_ONb tested twice, should 2nd be P2G2CLK_DAC_ALWAYS_ONb?
  s3c-fb: CPUFREQ frequency scaling support
  s3c-fb: fix resource releasing on error during probing
  carminefb: fix possible access beyond end of carmine_modedb[]
  acornfb: remove fb_mmap function
  mb862xxfb: use CONFIG_OF instead of CONFIG_PPC_OF
  mb862xxfb: restrict compliation of platform driver to PPC
  Samsung SoC Framebuffer driver: add Alpha Channel support
  atmel-lcdc: fix pixclock upper bound detection
  offb: use framebuffer_alloc() to allocate fb_info struct
  ...

Manually fix up conflicts due to kmemcheck in mm/slab.c
2009-06-16 19:50:13 -07:00
David Rientjes 2ff05b2b4e oom: move oom_adj value from task_struct to mm_struct
The per-task oom_adj value is a characteristic of its mm more than the
task itself since it's not possible to oom kill any thread that shares the
mm.  If a task were to be killed while attached to an mm that could not be
freed because another thread were set to OOM_DISABLE, it would have
needlessly been terminated since there is no potential for future memory
freeing.

This patch moves oomkilladj (now more appropriately named oom_adj) from
struct task_struct to struct mm_struct.  This requires task_lock() on a
task to check its oom_adj value to protect against exec, but it's already
necessary to take the lock when dereferencing the mm to find the total VM
size for the badness heuristic.

This fixes a livelock if the oom killer chooses a task and another thread
sharing the same memory has an oom_adj value of OOM_DISABLE.  This occurs
because oom_kill_task() repeatedly returns 1 and refuses to kill the
chosen task while select_bad_process() will repeatedly choose the same
task during the next retry.

Taking task_lock() in select_bad_process() to check for OOM_DISABLE and in
oom_kill_task() to check for threads sharing the same memory will be
removed in the next patch in this series where it will no longer be
necessary.

Writing to /proc/pid/oom_adj for a kthread will now return -EINVAL since
these threads are immune from oom killing already.  They simply report an
oom_adj value of OOM_DISABLE.

Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16 19:47:43 -07:00
Linus Torvalds 23059a0df5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
  fat: split fat_generic_ioctl
  FAT: add 'errors' mount option
2009-06-16 11:29:44 -07:00
J. Bruce Fields 7eef4091a6 Merge commit 'v2.6.30' into for-2.6.31 2009-06-15 18:08:07 -07:00
Linus Torvalds 9c7cb99a82 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (22 commits)
  nilfs2: support contiguous lookup of blocks
  nilfs2: add sync_page method to page caches of meta data
  nilfs2: use device's backing_dev_info for btree node caches
  nilfs2: return EBUSY against delete request on snapshot
  nilfs2: modify list of unsupported features in caveats
  nilfs2: enable sync_page method
  nilfs2: set bio unplug flag for the last bio in segment
  nilfs2: allow future expansion of metadata read out via get info ioctl
  NILFS2: Pagecache usage optimization on NILFS2
  nilfs2: remove nilfs_btree_operations from btree mapping
  nilfs2: remove nilfs_direct_operations from direct mapping
  nilfs2: remove bmap pointer operations
  nilfs2: remove useless b_low and b_high fields from nilfs_bmap struct
  nilfs2: remove pointless NULL check of bpop_commit_alloc_ptr function
  nilfs2: move get block functions in bmap.c into btree codes
  nilfs2: remove nilfs_bmap_delete_block
  nilfs2: remove nilfs_bmap_put_block
  nilfs2: remove header file for segment list operations
  nilfs2: eliminate removal list of segments
  nilfs2: add sufile function that can modify multiple segment usages
  ...
2009-06-15 09:13:49 -07:00
Linus Torvalds 489f7ab6c1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (31 commits)
  trivial: remove the trivial patch monkey's name from SubmittingPatches
  trivial: Fix a typo in comment of addrconf_dad_start()
  trivial: usb: fix missing space typo in doc
  trivial: pci hotplug: adding __init/__exit macros to sgi_hotplug
  trivial: Remove the hyphen from git commands
  trivial: fix ETIMEOUT -> ETIMEDOUT typos
  trivial: Kconfig: .ko is normally not included in module names
  trivial: SubmittingPatches: fix typo
  trivial: Documentation/dell_rbu.txt: fix typos
  trivial: Fix Pavel's address in MAINTAINERS
  trivial: ftrace:fix description of trace directory
  trivial: unnecessary (void*) cast removal in sound/oss/msnd.c
  trivial: input/misc: Fix typo in Kconfig
  trivial: fix grammo in bus_for_each_dev() kerneldoc
  trivial: rbtree.txt: fix rb_entry() parameters in sample code
  trivial: spelling fix in ppc code comments
  trivial: fix typo in bio_alloc kernel doc
  trivial: Documentation/rbtree.txt: cleanup kerneldoc of rbtree.txt
  trivial: Miscellaneous documentation typo fixes
  trivial: fix typo milisecond/millisecond for documentation and source comments.
  ...
2009-06-14 13:46:25 -07:00
Linus Torvalds 1904187a69 Merge branch 'docs-next' of git://git.lwn.net/linux-2.6
* 'docs-next' of git://git.lwn.net/linux-2.6:
  Document the debugfs API
  Documentation: Add "how to write a good patch summary" to SubmittingPatches
  SubmittingPatches: fix typo
  docs: Encourage better changelogs in the development process document
  Document Reported-by in SubmittingPatches
2009-06-13 13:08:34 -07:00
Theodore Ts'o 8a8a2050c8 ext4: document the "abort" mount option
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-13 10:08:59 -04:00
Matt LaPlante 19f5946001 trivial: Miscellaneous documentation typo fixes
Fix various typos in documentation txts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12 18:01:47 +02:00
Linus Torvalds 0a33f80a83 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (25 commits)
  GFS2: Merge gfs2_get_sb into gfs2_get_sb_meta
  GFS2: Fix cache coherency between truncate and O_DIRECT read
  GFS2: Fix locking issue mounting gfs2meta fs
  GFS2: Remove unused variable
  GFS2: smbd proccess hangs with flock() call.
  GFS2: Remove args subdir from gfs2 sysfs files
  GFS2: Remove lockstruct subdir from gfs2 sysfs files
  GFS2: Move gfs2_unlink_ok into ops_inode.c
  GFS2: Move gfs2_readlinki into ops_inode.c
  GFS2: Move gfs2_rmdiri into ops_inode.c
  GFS2: Merge mount.c and ops_super.c into super.c
  GFS2: Clean up some file names
  GFS2: Be more aggressive in reclaiming unlinked inodes
  GFS2: Add a rgrp bitmap full flag
  GFS2: Improve resource group error handling
  GFS2: Don't warn when delete inode fails on ro filesystem
  GFS2: Update docs
  GFS2: Umount recovery race fix
  GFS2: Remove a couple of unused sysfs entries
  GFS2: Add commit= mount option
  ...
2009-06-11 10:36:12 -07:00
Ryusuke Konishi fb6e7113ae nilfs2: modify list of unsupported features in caveats
This clarifies missing features of nilfs as a regular filesystem.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2009-06-10 23:41:11 +09:00
Jonathan Corbet f89d7eaf6c Document the debugfs API
This is an updated document covering the internal API for the debugfs
filesystem.  Thanks to Shen Feng for suggesting that I put this text here
and noting that the old LWN version was rather out of date.

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reported-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-06-06 10:28:14 -06:00
Denis Karpov 85c7859190 FAT: add 'errors' mount option
On severe errors FAT remounts itself in read-only mode. Allow to
specify FAT fs desired behavior through 'errors' mount option:
panic, continue or remount read-only.

`mount -t [fat|vfat] -o errors=[panic,remount-ro,continue] \
	<bdev> <mount point>`

This is analog to ext2 fs 'errors' mount option.

Signed-off-by: Denis Karpov <ext-denis.2.karpov@nokia.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2009-06-04 02:34:51 +09:00
Hugh Dickins 98f32602d4 hugh: update email address
My old address will shut down in a few days time: remove it from the tree,
and add a tmpfs (shmem filesystem) maintainer entry with the new address.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-21 13:14:32 -07:00
Steven Whitehouse e9ccb73ab5 GFS2: Update docs
Update a few things which were out of date, and fix a typo.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-05-19 10:23:23 +01:00
Nick Piggin b827e496c8 mm: close page_mkwrite races
Change page_mkwrite to allow implementations to return with the page
locked, and also change it's callers (in page fault paths) to hold the
lock until the page is marked dirty.  This allows the filesystem to have
full control of page dirtying events coming from the VM.

Rather than simply hold the page locked over the page_mkwrite call, we
call page_mkwrite with the page unlocked and allow callers to return with
it locked, so filesystems can avoid LOR conditions with page lock.

The problem with the current scheme is this: a filesystem that wants to
associate some metadata with a page as long as the page is dirty, will
perform this manipulation in its ->page_mkwrite.  It currently then must
return with the page unlocked and may not hold any other locks (according
to existing page_mkwrite convention).

In this window, the VM could write out the page, clearing page-dirty.  The
filesystem has no good way to detect that a dirty pte is about to be
attached, so it will happily write out the page, at which point, the
filesystem may manipulate the metadata to reflect that the page is no
longer dirty.

It is not always possible to perform the required metadata manipulation in
->set_page_dirty, because that function cannot block or fail.  The
filesystem may need to allocate some data structure, for example.

And the VM cannot mark the pte dirty before page_mkwrite, because
page_mkwrite is allowed to fail, so we must not allow any window where the
page could be written to if page_mkwrite does fail.

This solution of holding the page locked over the 3 critical operations
(page_mkwrite, setting the pte dirty, and finally setting the page dirty)
closes out races nicely, preventing page cleaning for writeout being
initiated in that window.  This provides the filesystem with a strong
synchronisation against the VM here.

- Sage needs this race closed for ceph filesystem.
- Trond for NFS (http://bugzilla.kernel.org/show_bug.cgi?id=12913).
- I need it for fsblock.
- I suspect other filesystems may need it too (eg. btrfs).
- I have converted buffer.c to the new locking. Even simple block allocation
  under dirty pages might be susceptible to i_size changing under partial page
  at the end of file (we also have a buffer.c-side problem here, but it cannot
  be fixed properly without this patch).
- Other filesystems (eg. NFS, maybe btrfs) will need to change their
  page_mkwrite functions themselves.

[ This also moves page_mkwrite another step closer to fault, which should
  eventually allow page_mkwrite to be moved into ->fault, and thus avoiding a
  filesystem calldown and page lock/unlock cycle in __do_fault. ]

[akpm@linux-foundation.org: fix derefs of NULL ->mapping]
Cc: Sage Weil <sage@newdream.net>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:09 -07:00
Benny Halevy 4ba170c2bb update Documentation/filesystems/00-INDEX with new nfsd related docs.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Cc: James Lentini <jlentini@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-04-28 12:54:45 -04:00
Marc Dionne 91ac033d83 CacheFiles: Fix the documentation to use the correct credential pointer names
Adjust the CacheFiles documentation to use the correct names of the credential
pointers in task_struct.

The documentation was using names from the old versions of the credentials
patches.

Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-24 13:28:30 -07:00
Adrian McMenamin 66672fefaa Documentation/filesystems: remove out of date reference to BKL being held
Documentation/filesystems/vfs.txt incorrectly states that the kernel is
locked during the call to statfs (Documentation/filesystems/Locking
correctly says it is not). This patch removes the offending sentence.

remove reference to BKL being held in statfs

Signed-off-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:01:16 -04:00
Evgeniy Polyakov e0ca873916 Staging: Pohmelfs: Added IO permissions and priorities.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-17 11:06:30 -07:00
Ryusuke Konishi 458c5b0822 nilfs2: clean up sketch file
The sketch file is a file to mark checkpoints with user data.  It was
experimentally introduced in the original implementation, and now
obsolete.  The file was handled differently with regular files; the file
size got truncated when a checkpoint was created.

This stops the special treatment and will treat it as a regular file.
Most users are not affected because mkfs.nilfs2 no longer makes this file.

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>
2009-04-07 08:31:19 -07:00
Ryusuke Konishi 962281a7ab nilfs2: add document
This adds a document describing the features, mount options, userland
tools, usage, disk format, and related URLs for the nilfs2 file system.

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>
2009-04-07 08:31:12 -07:00
Linus Torvalds a63856252d Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.30' of git://linux-nfs.org/~bfields/linux: (81 commits)
  nfsd41: define nfsd4_set_statp as noop for !CONFIG_NFSD_V4
  nfsd41: define NFSD_DRC_SIZE_SHIFT in set_max_drc
  nfsd41: Documentation/filesystems/nfs41-server.txt
  nfsd41: CREATE_EXCLUSIVE4_1
  nfsd41: SUPPATTR_EXCLCREAT attribute
  nfsd41: support for 3-word long attribute bitmask
  nfsd: dynamically skip encoded fattr bitmap in _nfsd4_verify
  nfsd41: pass writable attrs mask to nfsd4_decode_fattr
  nfsd41: provide support for minor version 1 at rpc level
  nfsd41: control nfsv4.1 svc via /proc/fs/nfsd/versions
  nfsd41: add OPEN4_SHARE_ACCESS_WANT nfs4_stateid bmap
  nfsd41: access_valid
  nfsd41: clientid handling
  nfsd41: check encode size for sessions maxresponse cached
  nfsd41: stateid handling
  nfsd: pass nfsd4_compound_state* to nfs4_preprocess_{state,seq}id_op
  nfsd41: destroy_session operation
  nfsd41: non-page DRC for solo sequence responses
  nfsd41: Add a create session replay cache
  nfsd41: create_session operation
  ...
2009-04-06 13:25:56 -07:00