Commit Graph

20309 Commits

Author SHA1 Message Date
Sage Weil 99d16cbcaf Btrfs: fix deadlock in btrfs_commit_transaction
We calculate timeout (either 1 or MAX_SCHEDULE_TIMEOUT) based on whether
num_writers > 1 or should_grow at the top of the loop.  Then, much much
later, we wait for that timeout if either num_writers or should_grow is
true.  However, it's possible for a racing process (calling
btrfs_end_transaction()) to decrement num_writers such that we wait
forever instead of for 1.

Fix this by deciding how long to wait when we wait.  Include a smp_mb()
before checking if the waitqueue is active to ensure the num_writers
is visible.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:34 -04:00
Sage Weil fccdae435c Btrfs: fix lockdep warning on clone ioctl
I'm no lockdep expert, but this appears to make the lockdep warning go
away for the i_mutex locking in the clone ioctl.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Sage Weil 050006a753 Btrfs: fix clone ioctl where range is adjacent to extent
We had an edge case issue where the requested range was just
following an existing extent. Instead of skipping to the next
extent, we used the previous one which lead to having zero
sized extents.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Sage Weil 9a019196ec Btrfs: fix delalloc checks in clone ioctl
The lookup_first_ordered_extent() was done on the wrong inode, and the
->delalloc_bytes test was wrong, as the following
btrfs_wait_ordered_range() would only invoke a range write and wouldn't
write the entire file data range. Also, a bad parameter was passed to
btrfs_wait_ordered_range().

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Chris Mason d8e39c457b Btrfs: drop unused variable in block_alloc_rsv
The alloc_target variable is not really used.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:17:41 -04:00
Andi Kleen 559af82114 Btrfs: cleanup warnings from gcc 4.6 (nonbugs)
These are all the cases where a variable is set, but not read which are
not bugs as far as I can see, but simply leftovers.

Still needs more review.

Found by gcc 4.6's new warnings

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:37 -04:00
Andi Kleen 411fc6bcef Btrfs: Fix variables set but not read (bugs found by gcc 4.6)
These are all the cases where a variable is set, but not
read which are really bugs.

- Couple of incorrect error handling fixed.
- One incorrect use of a allocation policy
- Some other things

Still needs more review.

Found by gcc 4.6's new warnings.

[akpm@linux-foundation.org: fix build.  Might have been bitrot]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:31 -04:00
Julia Lawall d0b678cb0a Btrfs: Use ERR_CAST helpers
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
 ...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:23 -04:00
Julia Lawall 2354d08fe9 Btrfs: use memdup_user helpers
Use memdup_user when user data is immediately copied into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

-  to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+  to = memdup_user(from,size);
   if (
-      to==NULL
+      IS_ERR(to)
                 || ...) {
   <+... when != goto l1;
-  -ENOMEM
+  PTR_ERR(to)
   ...+>
   }
-  if (copy_from_user(to, from, size) != 0) {
-    <+... when != goto l2;
-    -EFAULT
-    ...+>
-  }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:18 -04:00
Linus Torvalds b4020c1b19 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: Cleanup and thus reduce smb session structure and fields used during authentication
  NTLM auth and sign - Use appropriate server challenge
  cifs: add kfree() on error path
  NTLM auth and sign - minor error corrections and cleanup
  NTLM auth and sign - Use kernel crypto apis to calculate hashes and smb signatures
  NTLM auth and sign - Define crypto hash functions and create and send keys needed for key exchange
  cifs: cifs_convert_address() returns zero on error
  NTLM auth and sign - Allocate session key/client response dynamically
  cifs: update comments - [s/GlobalSMBSesLock/cifs_file_list_lock/g]
  cifs: eliminate cifsInodeInfo->write_behind_rc (try #6)
  [CIFS] Fix checkpatch warnings and bump cifs version number
  cifs: wait for writeback to complete in cifs_flush
  cifs: convert cifsFileInfo->count to non-atomic counter
2010-10-29 10:37:27 -07:00
Linus Torvalds 435f49a518 readv/writev: do the same MAX_RW_COUNT truncation that read/write does
We used to protect against overflow, but rather than return an error, do
what read/write does, namely to limit the total size to MAX_RW_COUNT.
This is not only more consistent, but it also means that any broken
low-level read/write routine that still keeps counts in 'int' can't
break.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-29 10:36:49 -07:00
Linus Torvalds 162164f7e9 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 function prototype
  Squashfs: fix use of __le64 annotated variable
2010-10-29 08:48:58 -07:00
Tyler Hicks 8747f95481 eCryptfs: Print mount_auth_tok_only param in ecryptfs_show_options
When printing mount options, print the new ecryptfs_mount_auth_tok_only
mount option.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:36 -05:00
Roberto Sassu f16feb5119 ecryptfs: added ecryptfs_mount_auth_tok_only mount parameter
This patch adds a new mount parameter 'ecryptfs_mount_auth_tok_only' to
force ecryptfs to use only authentication tokens which signature has
been specified at mount time with parameters 'ecryptfs_sig' and
'ecryptfs_fnek_sig'. In this way, after disabling the passthrough and
the encrypted view modes, it's possible to make available to users only
files encrypted with the specified authentication token.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: James Morris <jmorris@namei.org>
[Tyler: Clean up coding style errors found by checkpatch]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:36 -05:00
Roberto Sassu 39fac853a7 ecryptfs: checking return code of ecryptfs_find_auth_tok_for_sig()
This patch replaces the check of the 'matching_auth_tok' pointer with
the exit status of ecryptfs_find_auth_tok_for_sig().
This avoids to use authentication tokens obtained through the function
ecryptfs_keyring_auth_tok_for_sig which are not valid.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:36 -05:00
Roberto Sassu aee683b9e7 ecryptfs: release keys loaded in ecryptfs_keyring_auth_tok_for_sig()
This patch allows keys requested in the function
ecryptfs_keyring_auth_tok_for_sig()to be released when they are no
longer required. In particular keys are directly released in the same
function if the obtained authentication token is not valid.

Further, a new function parameter 'auth_tok_key' has been added to
ecryptfs_find_auth_tok_for_sig() in order to provide callers the key
pointer to be passed to key_put().

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: James Morris <jmorris@namei.org>
[Tyler: Initialize auth_tok_key to NULL in ecryptfs_parse_packet_set]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:35 -05:00
Tyler Hicks 2e21b3f124 eCryptfs: Clear LOOKUP_OPEN flag when creating lower file
eCryptfs was passing the LOOKUP_OPEN flag through to the lower file
system, even though ecryptfs_create() doesn't support the flag. A valid
filp for the lower filesystem could be returned in the nameidata if the
lower file system's create() function supported LOOKUP_OPEN, possibly
resulting in unencrypted writes to the lower file.

However, this is only a potential problem in filesystems (FUSE, NFS,
CIFS, CEPH, 9p) that eCryptfs isn't known to support today.

https://bugs.launchpad.net/ecryptfs/+bug/641703

Reported-by: Kevin Buhr
Cc: stable <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:35 -05:00
Roberto Sassu 48b512e685 ecryptfs: call vfs_setxattr() in ecryptfs_setxattr()
Ecryptfs is a stackable filesystem which relies on lower filesystems the
ability of setting/getting extended attributes.

If there is a security module enabled on the system it updates the
'security' field of inodes according to the owned extended attribute set
with the function vfs_setxattr().  When this function is performed on a
ecryptfs filesystem the 'security' field is not updated for the lower
filesystem since the call security_inode_post_setxattr() is missing for
the lower inode.
Further, the call security_inode_setxattr() is missing for the lower inode,
leading to policy violations in the security module because specific
checks for this hook are not performed (i. e. filesystem
'associate' permission on SELinux is not checked for the lower filesystem).

This patch replaces the call of the setxattr() method of the lower inode
in the function ecryptfs_setxattr() with vfs_setxattr().

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: stable <stable@kernel.org>
Cc: Dustin Kirkland <kirkland@canonical.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-10-29 10:31:35 -05:00
Chris Mason 18e503d695 Btrfs: fix raid code for removing missing drives
When btrfs is mounted in degraded mode, it has some internal structures
to track the missing devices.  This missing device is setup as readonly,
but the mapping code can get upset when we try to write to it.

This changes the mapping code to return -EIO instead of oops when we try
to write to the readonly device.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:46 -04:00
Miao Xie 19fe0a8b78 Btrfs: Switch the extent buffer rbtree into a radix tree
This patch reduces the CPU time spent in the extent buffer search by using the
radix tree instead of the rbtree and using the rcu lock instead of the spin
lock.

I did a quick test by the benchmark tool[1] and found the patch improve the
file creation/deletion performance problem that I have reported[2].

Before applying this patch:
Create files:
	Total files: 50000
	Total time: 0.971531
	Average time: 0.000019
Delete files:
	Total files: 50000
	Total time: 1.366761
	Average time: 0.000027

After applying this patch:
Create files:
	Total files: 50000
	Total time: 0.927455
	Average time: 0.000019
Delete files:
	Total files: 50000
	Total time: 1.292280
	Average time: 0.000026

[1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3
[2] http://marc.info/?l=linux-btrfs&m=128212635122920&w=2

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:45 -04:00
Miao Xie 897ca6e9b4 Btrfs: restructure try_release_extent_buffer()
restructure try_release_extent_buffer() and write a function to release the
extent buffer. It will be used later.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:45 -04:00
Chris Mason bf9022e06a Btrfs: use the flusher threads for delalloc throttling
We have a fairly complex set of loops around walking our list of
delalloc inodes when we find metadata delalloc space running low.
It doesn't work very well, can use large amounts of CPU and doesn't
do very efficient writeback.

This switches us to kick the bdi flusher threads instead.  All dirty
data in btrfs is accounted as delalloc data, so this is very similar
in terms of what it writes, but we're able to just kick off the IO
and wait for progress.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:36 -04:00
Chris Mason e5bc245829 Btrfs: tune the chunk allocation to 5% of the FS as metadata
An earlier commit tried to keep us from allocating too many
empty metadata chunks.  It was somewhat too restrictive and could
lead to ENOSPC errors on empty filesystems.

This increases the limits to about 5% of the FS size, allowing more
metadata chunks to be preallocated.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:35 -04:00
Chris Mason 3259f8bed2 Add new functions for triggering inode writeback
When btrfs is running low on metadata space, it needs to force delayed
allocation pages to disk.  It currently does this with a suboptimal walk
of a private list of inodes with delayed allocation, and it would be
much better if we used the generic flusher threads.

writeback_inodes_sb_if_idle would be ideal, but it waits for the flusher
thread to start IO on all the dirty pages in the FS before it returns.
This adds variants of writeback_inodes_sb* that allow the caller to
control how many pages get sent down.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:29 -04:00
Chris Mason cb44921a09 Btrfs: don't loop forever on bad btree blocks
When btrfs discovers the generation number in a btree block is
incorrect, it can loop forever without forcing the RAID
code to try a valid mirror, and without returning EIO.

This changes things to properly kick out the EIO.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 09:31:30 -04:00
Chris Mason 6b5b817f10 Merge branch 'bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work
Conflicts:
	fs/btrfs/extent-tree.c

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 09:27:49 -04:00
Josef Bacik 8216ef866d Btrfs: let the user know space caching is enabled
If you mount -o space_cache, the option will be persistent across mounts, but to
make sure the user knows that they did this, emit a message telling them if they
didn't mount with -o space_cache but the feature is still used.

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:37 -04:00
Josef Bacik 88c2ba3b06 Btrfs: Add a clear_cache mount option
If something goes wrong with the free space cache we need a way to make sure
it's not loaded on mount and that it's cleared for everybody.  When you pass the
clear_cache option it will make it so all block groups are setup to be cleared,
which keeps them from being loaded and then they will be truncated when the
transaction is committed.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:36 -04:00
Josef Bacik 67377734fd Btrfs: add support for mixed data+metadata block groups
There are just a few things that need to be fixed in the kernel to support mixed
data+metadata block groups.  Mostly we just need to make sure that if we are
using mixed block groups that we continue to allocate mixed block groups as we
need them.  Also we need to make sure __find_space_info will find our space info
if we search for DATA or METADATA only.  Tested this with xfstests and it works
nicely.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:36 -04:00
Josef Bacik dde5abee12 Btrfs: check cache->caching_ctl before returning if caching has started
With the free space disk caching we can mark the block group as started with the
caching, but we don't have a caching ctl.  This can race with anybody else who
tries to get the caching ctl before we cache (this is very hard to do btw).  So
instead check to see if cache->caching_ctl is set, and if not return NULL.
Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:35 -04:00
Josef Bacik 9d66e233c7 Btrfs: load free space cache if it exists
This patch actually loads the free space cache if it exists.  The only thing
that really changes here is that we need to cache the block group if we're going
to remove an extent from it.  Previously we did not do this since the caching
kthread would pick it up.  With the on disk cache we don't have this luxury so
we need to make sure we read the on disk cache in first, and then remove the
extent, that way when the extent is unpinned the free space is added to the
block group.  This has been tested with all sorts of things.

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:35 -04:00
Josef Bacik 0cb59c9953 Btrfs: write out free space cache
This is a simple bit, just dump the free space cache out to our preallocated
inode when we're writing out dirty block groups.  There are a bunch of changes
in inode.c in order to account for special cases.  Mostly when we're doing the
writeout we're holding trans_mutex, so we need to use the nolock transacation
functions.  Also we can't do asynchronous completions since the async thread
could be blocked on already completed IO waiting for the transaction lock.  This
has been tested with xfstests and btrfs filesystem balance, as well as my ENOSPC
tests.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:29 -04:00
Al Viro a4cdbd8bfb braino in internal.h
wrong return type...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 05:49:13 -04:00
Al Viro 31f43471e9 convert simple cases of nfs-related ->get_sb() to ->mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:23 -04:00
Al Viro 061dbc6b90 convert btrfs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:21 -04:00
Al Viro a7f9fb205a convert ceph
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:18 -04:00
Al Viro 8bcbbf0009 convert gfs2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:16 -04:00
Al Viro f7442b3be6 convert afs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:13 -04:00
Al Viro 4d143beb04 convert ecryptfs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:11 -04:00
Al Viro d0e46f88b2 convert sysfs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:08 -04:00
Al Viro ceefda6931 switch get_sb_ns() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:03 -04:00
Al Viro aed1d84f98 switch procfs to ->mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:01 -04:00
Al Viro 579441a39b setting ->proc_mnt doesn't belong in proc_get_sb()
take that to kern_mount_data()-using callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:58 -04:00
Al Viro d753ed9759 convert cifs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:56 -04:00
Al Viro e4c59d61e8 convert nilfs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:53 -04:00
Al Viro a1da9e8ab6 switch logfs to ->mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:51 -04:00
Al Viro e5a0726a95 logfs: fix a leak in get_sb
a) switch ->put_device() to logfs_super *
b) actually call it on early failures in logfs_get_sb_device()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:48 -04:00
Al Viro 7d945a3aa7 logfs get_sb, part 3
take logfs_get_sb_device() calls to logfs_get_sb() itself

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:46 -04:00
Al Viro 0d85c79962 logfs get_sb, part 2
take setting s_bdev/s_mtd/s_devops to callers of logfs_get_sb_device(),
don't bother passing them separately

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:43 -04:00
Al Viro 71a1c0125f logfs get_sb massage, part 1
move allocation of logfs_super to logfs_get_sb, pass it to
logfs_get_sb_...().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:41 -04:00
Al Viro d2d1ea9306 convert v9fs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:38 -04:00
Al Viro 157d81e7ff convert ubifs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:36 -04:00
Al Viro 51139adac9 convert get_sb_pseudo() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:33 -04:00
Al Viro 3c26ff6e49 convert get_sb_nodev() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:31 -04:00
Al Viro fc14f2fef6 convert get_sb_single() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:28 -04:00
Al Viro 848b83a59b convert get_sb_mtd() users to ->mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:26 -04:00
Al Viro 152a083666 new helper: mount_bdev()
... and switch of the obvious get_sb_bdev() users to ->mount()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:13 -04:00
Al Viro c96e41e92b beginning of transtion: ->mount()
eventual replacement for ->get_sb() - does *not* get vfsmount,
return ERR_PTR(error) or root of subtree to be mounted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:15:06 -04:00
Al Viro d893f1bc2a fix open/umount race
nameidata_to_filp() drops nd->path or transfers it to opened
file.  In the former case it's a Bad Idea(tm) to do mnt_drop_write()
on nd->path.mnt, since we might race with umount and vfsmount in
question might be gone already.

Fix: don't drop it, then...  IOW, have nameidata_to_filp() grab nd->path
in case it transfers it to file and do path_drop() in callers.  After
they are through with accessing nd->path...

Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:14:56 -04:00
Al Viro a4118ee1d8 a couple of open-coded ihold() introduced by nfs merge
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:14:48 -04:00
Shirish Pargaonkar d3686d54c7 cifs: Cleanup and thus reduce smb session structure and fields used during authentication
Removed following fields from smb session structure
 cryptkey, ntlmv2_hash, tilen, tiblob
and ntlmssp_auth structure is allocated dynamically only if the auth mech
in NTLMSSP.

response field within a session_key structure is used to initially store the
target info (either plucked from type 2 challenge packet in case of NTLMSSP
or fabricated in case of NTLMv2 without extended security) and then to store
Message Authentication Key (mak) (session key + client response).

Server challenge or cryptkey needed during a NTLMSSP authentication
is now part of ntlmssp_auth structure which gets allocated and freed
once authenticaiton process is done.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:33 +00:00
Shirish Pargaonkar d3ba50b17a NTLM auth and sign - Use appropriate server challenge
Need to have cryptkey or server challenge in smb connection
(struct TCP_Server_Info) for ntlm and ntlmv2 auth types for which
cryptkey (Encryption Key) is supplied just once in Negotiate Protocol
response during an smb connection setup for all the smb sessions over
that smb connection.

For ntlmssp, cryptkey or server challenge is provided for every
smb session in type 2 packet of ntlmssp negotiation, the cryptkey
provided during Negotiation Protocol response before smb connection
does not count.

Rename cryptKey to cryptkey and related changes.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:30 +00:00
Linus Torvalds 671f837a04 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: BUG_ON fix: check if page has buffers before calling page_buffers()
2010-10-28 15:46:57 -07:00
Linus Torvalds a0e3390787 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:
  nfs4: The difference of 2 pointers is ptrdiff_t
  nfs: testing the wrong variable
  nfs: handle lock context allocation failures in nfs_create_request
  Fixed Regression in NFS Direct I/O path
2010-10-28 15:13:05 -07:00
Theodore Ts'o b1142e8fec ext4: BUG_ON fix: check if page has buffers before calling page_buffers()
We need to make check if a page does not have buffes by checking
page_has_buffers(page) before calling page_buffers(page) in
ext4_writepage().  Otherwise page_buffers() could throw a BUG_ON.

Thanks also to Markus Trippelsdorf and Avinash Kurup who also reported
the problem.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Sedat Dilek <sedat.dilek@googlemail.com>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com>
2010-10-28 17:33:57 -04:00
Andrew Morton 19ba54f464 fs/notify/fanotify/fanotify_user.c: fix warnings
fs/notify/fanotify/fanotify_user.c: In function 'fanotify_release':
fs/notify/fanotify/fanotify_user.c:375: warning: unused variable 'lre'
fs/notify/fanotify/fanotify_user.c:375: warning: unused variable 're'

this is really ugly.

Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:16 -04:00
Eric Paris 192ca4d194 fanotify: do not recalculate the mask if the ignored mask changed
If fanotify sets a new bit in the ignored mask it will cause the generic
fsnotify layer to recalculate the real mask.  This is stupid since we
didn't change that part.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:16 -04:00
Eric Paris 8fcd65280a fanotify: ignore events on directories unless specifically requested
fanotify has a very limited number of events it sends on directories.  The
usefulness of these events is yet to be seen and still we send them.  This
is particularly painful for mount marks where one might receive many of
these useless events.  As such this patch will drop events on IS_DIR()
inodes unless they were explictly requested with FAN_ON_DIR.

This means that a mark on a directory without FAN_EVENT_ON_CHILD or
FAN_ON_DIR is meaningless and will result in no events ever (although it
will still be allowed since detecting it is hard)

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:16 -04:00
Eric Paris b29866aab8 fsnotify: rename FS_IN_ISDIR to FS_ISDIR
The _IN_ in the naming is reserved for flags only used by inotify.  Since I
am about to use this flag for fanotify rename it to be generic like the
rest.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:15 -04:00
Eric Paris e1c048ba78 fanotify: do not send events for irregular files
fanotify_should_send_event has a test to see if an object is a file or
directory and does not send an event otherwise.  The problem is that the
test is actually checking if the object with a mark is a file or directory,
not if the object the event happened on is a file or directory.  We should
check the latter.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:15 -04:00
Eric Paris 4afeff8505 fanotify: limit number of listeners per user
fanotify currently has no limit on the number of listeners a given user can
have open.  This patch limits the total number of listeners per user to
128.  This is the same as the inotify default limit.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:15 -04:00
Eric Paris ac7e22dcfa fanotify: allow userspace to override max marks
Some fanotify groups, especially those like AV scanners, will need to place
lots of marks, particularly ignore marks.  Since ignore marks do not pin
inodes in cache and are cleared if the inode is removed from core (usually
under memory pressure) we expose an interface for listeners, with
CAP_SYS_ADMIN, to override the maximum number of marks and be allowed to
set and 'unlimited' number of marks.  Programs which make use of this
feature will be able to OOM a machine.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:15 -04:00
Eric Paris e7099d8a5a fanotify: limit the number of marks in a single fanotify group
There is currently no limit on the number of marks a given fanotify group
can have.  Since fanotify is gated on CAP_SYS_ADMIN this was not seen as
a serious DoS threat.  This patch implements a default of 8192, the same as
inotify to work towards removing the CAP_SYS_ADMIN gating and eliminating
the default DoS'able status.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:14 -04:00
Eric Paris 5dd03f55fd fanotify: allow userspace to override max queue depth
fanotify has a defualt max queue depth.  This patch allows processes which
explicitly request it to have an 'unlimited' queue depth.  These processes
need to be very careful to make sure they cannot fall far enough behind
that they OOM the box.  Thus this flag is gated on CAP_SYS_ADMIN.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:14 -04:00
Eric Paris 2529a0df0f fsnotify: implement a default maximum queue depth
Currently fanotify has no maximum queue depth.  Since fanotify is
CAP_SYS_ADMIN only this does not pose a normal user DoS issue, but it
certianly is possible that an fanotify listener which can't keep up could
OOM the box.  This patch implements a default 16k depth.  This is the same
default depth used by inotify, but given fanotify's better queue merging in
many situations this queue will contain many additional useful events by
comparison.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:14 -04:00
Eric Paris 5322a59f14 fanotify: ignore fanotify ignore marks if open writers
fanotify will clear ignore marks if a task changes the contents of an
inode.  The problem is with the races around when userspace finishes
checking a file and when that result is actually attached to the inode.
This race was described as such:

Consider the following scenario with hostile processes A and B, and
victim process C:
1. Process A opens new file for writing. File check request is generated.
2. File check is performed in userspace. Check result is "file has no malware".
3. The "permit" response is delivered to kernel space.
4. File ignored mark set.
5. Process A writes dummy bytes to the file. File ignored flags are cleared.
6. Process B opens the same file for reading. File check request is generated.
7. File check is performed in userspace. Check result is "file has no malware".
8. Process A writes malware bytes to the file. There is no cached response yet.
9. The "permit" response is delivered to kernel space and is cached in fanotify.
10. File ignored mark set.
11. Now any process C will be permitted to open the malware file.
There is a race between steps 8 and 10

While fanotify makes no strong guarantees about systems with hostile
processes there is no reason we cannot harden against this race.  We do
that by simply ignoring any ignore marks if the inode has open writers (aka
i_writecount > 0).  (We actually do not ignore ignore marks if the
FAN_MARK_SURV_MODIFY flag is set)

Reported-by: Vasily Novikov <vasily.novikov@kaspersky.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:14 -04:00
Eric Paris 52420392c8 fsnotify: call fsnotify_parent in perm events
fsnotify perm events do not call fsnotify parent.  That means you cannot
register a perm event on a directory and enforce permissions on all inodes in
that directory.  This patch fixes that situation.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:13 -04:00
Eric Paris ff8bcbd03d fsnotify: correctly handle return codes from listeners
When fsnotify groups return errors they are ignored.  For permissions
events these should be passed back up the stack, but for most events these
should continue to be ignored.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:13 -04:00
Eric Paris 4231a23530 fanotify: implement fanotify listener ordering
The fanotify listeners needs to be able to specify what types of operations
they are going to perform so they can be ordered appropriately between other
listeners doing other types of operations.  They need this to be able to make
sure that things like hierarchichal storage managers will get access to inodes
before processes which need the data.  This patch defines 3 possible uses
which groups must indicate in the fanotify_init() flags.

FAN_CLASS_PRE_CONTENT
FAN_CLASS_CONTENT
FAN_CLASS_NOTIF

Groups will receive notification in that order.  The order between 2 groups in
the same class is undeterministic.

FAN_CLASS_PRE_CONTENT is intended to be used by listeners which need access to
the inode before they are certain that the inode contains it's final data.  A
hierarchical storage manager should choose to use this class.

FAN_CLASS_CONTENT is intended to be used by listeners which need access to the
inode after it contains its intended contents.  This would be the appropriate
level for an AV solution or document control system.

FAN_CLASS_NOTIF is intended for normal async notification about access, much the
same as inotify and dnotify.  Syncronous permissions events are not permitted
at this class.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:13 -04:00
Eric Paris 6ad2d4e3e9 fsnotify: implement ordering between notifiers
fanotify needs to be able to specify that some groups get events before
others.  They use this idea to make sure that a hierarchical storage
manager gets access to files before programs which actually use them.  This
is purely infrastructure.  Everything will have a priority of 0, but the
infrastructure will exist for it to be non-zero.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:13 -04:00
Eric Paris 9343919c14 fanotify: allow fanotify to be built
We disabled the ability to build fanotify in commit 7c5347733d.
This reverts that commit and allows people to build fanotify.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-10-28 17:22:13 -04:00
Josef Bacik 0af3d00bad Btrfs: create special free space cache inode
In order to save free space cache, we need an inode to hold the data, and we
need a special item to point at the right inode for the right block group.  So
first, create a special item that will point to the right inode, and the number
of extent entries we will have and the number of bitmaps we will have.  We
truncate and pre-allocate space everytime to make sure it's uptodate.

This feature will be turned on as soon as you mount with -o space_cache, however
it is safe to boot into old kernels, they will just generate the cache the old
fashion way.  When you boot back into a newer kernel we will notice that we
modified and not the cache and automatically discard the cache.

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-28 15:59:09 -04:00
Geert Uytterhoeven 12364a4f05 nfs4: The difference of 2 pointers is ptrdiff_t
On m68k, which is 32-bit:

fs/nfs/nfs4proc.c: In function ‘nfs41_sequence_done’:
fs/nfs/nfs4proc.c:432: warning: format ‘%ld’ expects type ‘long int’, but argument 3 has type ‘int’
fs/nfs/nfs4proc.c: In function ‘nfs4_setup_sequence’:
fs/nfs/nfs4proc.c:576: warning: format ‘%ld’ expects type ‘long int’, but argument 5 has type ‘int’

On 32-bit, ptrdiff_t is int; on 64-bit, ptrdiff_t is long.

Introduced by commit dfb4f30983 ("NFSv4.1: keep
seq_res.sr_slot as pointer rather than an index")

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-28 15:49:29 -04:00
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
Phillip Lougher 5f3b321da1 Squashfs: fix function prototype
The fourth argument should be unsigned.  Also add missing include
so that the function prototype is defined in xattr_id.c

This fixes a couple of sparse warnings.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2010-10-28 17:44:19 +01:00
Phillip Lougher 07724586b4 Squashfs: fix use of __le64 annotated variable
This fixes a sparse with endian checking warning.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2010-10-28 17:44:11 +01:00
Linus Torvalds 11cc21f5f5 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/hfsplus
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/hfsplus:
  hfsplus: free space correcly for files unlinked while open
  hfsplus: fix double lock typo in ioctl
2010-10-28 09:32:05 -07:00
Ingo Molnar 19ef20143f ext4: fix compile with CONFIG_EXT4_FS_XATTR disabled
Commit 5dabfc78dc ("ext4: rename {exit,init}_ext4_*() to
ext4_{exit,init}_*()") causes

  fs/ext4/super.c:4776: error: implicit declaration of function ‘ext4_init_xattr’

when CONFIG_EXT4_FS_XATTR is disabled.

It renamed init_ext4_xattr to ext4_init_xattr but forgot to update the
dummy definition in fs/ext4/xattr.h.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-28 09:29:17 -07:00
Dan Carpenter 8f0d97b415 nfs: testing the wrong variable
The intent was to test "*desc" for allocation failures, but it tests
"desc" which is always a valid pointer here.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-28 11:18:00 -04:00
Jeff Layton 015f0212d5 nfs: handle lock context allocation failures in nfs_create_request
nfs_get_lock_context can return NULL on an allocation failure.
Regression introduced by commit f11ac8db.

Reported-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-28 11:17:25 -04:00
Steve Dickson 568a810d7e Fixed Regression in NFS Direct I/O path
A typo, introduced by commit f11ac8db, in the nfs_direct_write()
routine causes writes with O_DIRECT set to fail with a ENOMEM error.

Found-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve Dickson <steved@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-28 11:14:05 -04:00
Venkateswararao Jujjuri (JV) b165d60145 9p: Add datasync to client side TFSYNC/RFSYNC for dotl
SYNOPSIS
    size[4] Tfsync tag[2] fid[4] datasync[4]

    size[4] Rfsync tag[2]

DESCRIPTION

    The Tfsync transaction transfers ("flushes") all modified in-core data of
    file identified by fid to the disk device (or other  permanent  storage
    device)  where that  file  resides.

    If datasync flag is specified data will be fleshed but does not flush
    modified metadata unless  that  metadata  is  needed  in order to allow a
    subsequent data retrieval to be correctly handled.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-10-28 09:08:49 -05:00
Aneesh Kumar K.V 877cb3d4dd fs/9p: Use generic_file_open with lookup_instantiate_filp
We need to do O_LARGEFILE check even in case of 9p. Use the
generic_file_open helper

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 09:08:48 -05:00
Aneesh Kumar K.V 9856af8b53 fs/9p: Add missing iput in v9fs_vfs_lookup
Make sure we drop inode reference in the error path

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 09:08:48 -05:00
Aneesh Kumar K.V f5fc6145f3 fs/9p: Use mknod 9p operation on create without open request
A create without LOOKUP_OPEN flag set is due to mknod of regular
files. Use mknod 9P operation for the same

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 09:08:48 -05:00
M. Mohan Kumar 329176cc2c 9p: Implement TREADLINK operation for 9p2000.L
Synopsis

	size[4] TReadlink tag[2] fid[4]
	size[4] RReadlink tag[2] target[s]

Description
	Readlink is used to return the contents of the symoblic link
        referred by fid. Contents of symboic link is returned as a
        response.

	target[s] - Contents of the symbolic link referred by fid.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-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 09:08:48 -05:00
M. Mohan Kumar 368c09d2a3 9p: Use V9FS_MAGIC in statfs
Use V9FS_MAGIC as the file system type while filling kernel statfs
strucutre instead of using host file system magic number. Also move
the definition of V9FS_MAGIC from v9fs.h to standard magic.h file.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-10-28 09:08:47 -05:00
M. Mohan Kumar 1d769cd192 9p: Implement TGETLOCK
Synopsis

    size[4] TGetlock tag[2] fid[4] getlock[n]
    size[4] RGetlock tag[2] getlock[n]

Description

TGetlock is used to test for the existence of byte range posix locks on a file
identified by given fid. The reply contains getlock structure. If the lock could
be placed it returns F_UNLCK in type field of getlock structure.  Otherwise it
returns the details of the conflicting locks in the getlock structure

    getlock structure:
      type[1] - Type of lock: F_RDLCK, F_WRLCK
      start[8] - Starting offset for lock
      length[8] - Number of bytes to check for the lock
             If length is 0, check for lock in all bytes starting at the location
            'start' through to the end of file
      pid[4] - PID of the process that wants to take lock/owns the task
               in case of reply
      client[4] - Client id of the system that owns the process which
                  has the conflicting lock

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
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 09:08:47 -05:00
M. Mohan Kumar a099027c77 9p: Implement TLOCK
Synopsis

    size[4] TLock tag[2] fid[4] flock[n]
    size[4] RLock tag[2] status[1]

Description

Tlock is used to acquire/release byte range posix locks on a file
identified by given fid. The reply contains status of the lock request

    flock structure:
        type[1] - Type of lock: F_RDLCK, F_WRLCK, F_UNLCK
        flags[4] - Flags could be either of
          P9_LOCK_FLAGS_BLOCK - Blocked lock request, if there is a
            conflicting lock exists, wait for that lock to be released.
          P9_LOCK_FLAGS_RECLAIM - Reclaim lock request, used when client is
            trying to reclaim a lock after a server restrart (due to crash)
        start[8] - Starting offset for lock
        length[8] - Number of bytes to lock
          If length is 0, lock all bytes starting at the location 'start'
          through to the end of file
        pid[4] - PID of the process that wants to take lock
        client_id[4] - Unique client id

        status[1] - Status of the lock request, can be
          P9_LOCK_SUCCESS(0), P9_LOCK_BLOCKED(1), P9_LOCK_ERROR(2) or
          P9_LOCK_GRACE(3)
          P9_LOCK_SUCCESS - Request was successful
          P9_LOCK_BLOCKED - A conflicting lock is held by another process
          P9_LOCK_ERROR - Error while processing the lock request
          P9_LOCK_GRACE - Server is in grace period, it can't accept new lock
            requests in this period (except locks with
            P9_LOCK_FLAGS_RECLAIM flag set)

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
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 09:08:47 -05:00