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10715 commits

Author SHA1 Message Date
Artem Bityutskiy
24fa9e9438 UBIFS: fix tnc dumping
debugfs tnc dumping was broken because of an obvious typo.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-23 12:22:39 +02:00
Artem Bityutskiy
7bbe5b5aa6 UBIFS: use PAGE_CACHE_MASK correctly
It has high bits set, not low bits set as the UBIFS code
assumed.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-23 12:19:14 +02:00
Alexey Dobriyan
995be04548 UBIFS: fix section mismatch
This patch fixes the following section mismatch:

WARNING: fs/ubifs/ubifs.o(.init.text+0xec): Section mismatch in reference from the function init_module() to the function .exit.text:ubifs_compressors_exit()

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-04 17:53:10 +02:00
Artem Bityutskiy
2ba5f7ae81 UBIFS: introduce LPT dump function
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:34 +02:00
Artem Bityutskiy
787845bdea UBIFS: dump stack in LPT check functions
It is useful to know how we got to the checking function when
hunting the bugs.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:34 +02:00
Artem Bityutskiy
45e12d901f UBIFS: run debugging checks only if they are enabled
Do not forget to check whether lpt debugging is enabled before
running the check functions. This commit also makes some spelling
fixes.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:34 +02:00
Artem Bityutskiy
552ff3179d UBIFS: add debugfs support
We need to have a possibility to see various UBIFS variables
and ask UBIFS to dump various information. Debugfs is what
we need.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:33 +02:00
Artem Bityutskiy
17c2f9f85c UBIFS: separate debugging fields out
Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:33 +02:00
Kukkonen Mika
5dd7cbc083 UBIFS: avoid unnecessary checks
I have a habit of compiling kernel with
EXTRA_CFLAGS="-Wextra -Wno-unused -Wno-sign-compare -Wno-missing-field-initializers"
and so fs/ubifs/key.h give lots (~10) of these every time:

CC      fs/ubifs/tnc_misc.o
In file included from fs/ubifs/ubifs.h:1725,
from fs/ubifs/tnc_misc.c:30:
fs/ubifs/key.h: In function 'key_r5_hash':
fs/ubifs/key.h:64: warning: comparison of unsigned expression >= 0 is always true
fs/ubifs/key.h: In function 'key_test_hash':
fs/ubifs/key.h:81: warning: comparison of unsigned expression >= 0 is always true

This patch fixes the warnings.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:11 +02:00
Artem Bityutskiy
553dea4dd5 UBIFS: introduce compression mount options
It is very handy to be able to change default UBIFS compressor
via mount options. Introduce -o compr=<name> mount option support.
Currently only "none", "lzo" and "zlib" compressors are supported.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:05 +02:00
Artem Bityutskiy
a1dc080c27 UBIFS: use bit-fields to store compression type
Save a 4 bytes of RAM per 'struct inode' by stroring inode
compression type in bit-filed, instead of using 'int'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:13:59 +02:00
Artem Bityutskiy
062e4fee44 UBIFS: slight compression optimization
If data does not compress, it is better to leave it uncompressed
because we'll read it faster then. So do not compress data if we
save less than 64 bytes.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:13:50 +02:00
Linus Torvalds
51eaaa6776 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
  UBIFS: pre-allocate bulk-read buffer
  UBIFS: do not allocate too much
  UBIFS: do not print scary memory allocation warnings
  UBIFS: allow for gaps when dirtying the LPT
  UBIFS: fix compilation warnings
  MAINTAINERS: change UBI/UBIFS git tree URLs
  UBIFS: endian handling fixes and annotations
  UBIFS: remove printk
2008-12-02 15:56:55 -08:00
Randy Dunlap
0380155363 ntfs: don't fool kernel-doc
kernel-doc handles macros now (it has for quite some time), so change the
ntfs_debug() macro's kernel-doc to be just before the macro instead of
before a phony function prototype.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:25 -08:00
Davide Libenzi
7ef9964e6d epoll: introduce resource usage limits
It has been thought that the per-user file descriptors limit would also
limit the resources that a normal user can request via the epoll
interface.  Vegard Nossum reported a very simple program (a modified
version attached) that can make a normal user to request a pretty large
amount of kernel memory, well within the its maximum number of fds.  To
solve such problem, default limits are now imposed, and /proc based
configuration has been introduced.  A new directory has been created,
named /proc/sys/fs/epoll/ and inside there, there are two configuration
points:

  max_user_instances = Maximum number of devices - per user

  max_user_watches   = Maximum number of "watched" fds - per user

The current default for "max_user_watches" limits the memory used by epoll
to store "watches", to 1/32 of the amount of the low RAM.  As example, a
256MB 32bit machine, will have "max_user_watches" set to roughly 90000.
That should be enough to not break existing heavy epoll users.  The
default value for "max_user_instances" is set to 128, that should be
enough too.

This also changes the userspace, because a new error code can now come out
from EPOLL_CTL_ADD (-ENOSPC).  The EMFILE from epoll_create() was already
listed, so that should be ok.

[akpm@linux-foundation.org: use get_current_user()]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:24 -08:00
Mark Fasheh
d6b58f89f7 ocfs2: fix regression in ocfs2_read_blocks_sync()
We're panicing in ocfs2_read_blocks_sync() if a jbd-managed buffer is seen.
At first glance, this seems ok but in reality it can happen. My test case
was to just run 'exorcist'. A struct inode is being pushed out of memory but
is then re-read at a later time, before the buffer has been checkpointed by
jbd. This causes a BUG to be hit in ocfs2_read_blocks_sync().

Reviewed-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:58 -08:00
Coly Li
07d9a3954a ocfs2: fix return value set in init_dlmfs_fs()
In init_dlmfs_fs(), if calling kmem_cache_create() failed, the code will use return value from
calling bdi_init(). The correct behavior should be set status as -ENOMEM before going to "bail:".

Signed-off-by: Coly Li <coyli@suse.de>
Acked-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:55 -08:00
David Teigland
07f9eebcdf ocfs2: fix wake_up in unlock_ast
In ocfs2_unlock_ast(), call wake_up() on lockres before releasing
the spin lock on it.  As soon as the spin lock is released, the
lockres can be freed.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:45 -08:00
David Teigland
66f502a416 ocfs2: initialize stack_user lvbptr
The locking_state dump, ocfs2_dlm_seq_show, reads the lvb on locks where it
has not yet been initialized by a lock call.

Signed-off-by: David Teigland <teigland@redhat.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:39 -08:00
Coly Li
3b5da0189c ocfs2: comments typo fix
This patch fixes two typos in comments of ocfs2.

Signed-off-by: Coly Li <coyli@suse.de>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:31 -08:00
Linus Torvalds
8e36a5d6ad 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] fix regression in cifs_write_begin/cifs_write_end
2008-11-30 14:04:02 -08:00
Jan Kara
52b19ac993 udf: Fix BUG_ON() in destroy_inode()
udf_clear_inode() can leave behind buffers on mapping's i_private list (when
we truncated preallocation). Call invalidate_inode_buffers() so that the list
is properly cleaned-up before we return from udf_clear_inode(). This is ugly
and suggest that we should cleanup preallocation earlier than in clear_inode()
but currently there's no such call available since drop_inode() is called under
inode lock and thus is unusable for disk operations.

Signed-off-by: Jan Kara <jack@suse.cz>
2008-11-27 17:38:28 +01:00
Jeff Layton
a98ee8c1c7 [CIFS] fix regression in cifs_write_begin/cifs_write_end
The conversion to write_begin/write_end interfaces had a bug where we
were passing a bad parameter to cifs_readpage_worker. Rather than
passing the page offset of the start of the write, we needed to pass the
offset of the beginning of the page. This was reliably showing up as
data corruption in the fsx-linux test from LTP.

It also became evident that this code was occasionally doing unnecessary
read calls. Optimize those away by using the PG_checked flag to indicate
that the unwritten part of the page has been initialized.

CC: Nick Piggin <npiggin@suse.de>
Acked-by: Dave Kleikamp <shaggy@us.ibm.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-26 19:32:33 +00:00
Artem Bityutskiy
3477d20465 UBIFS: pre-allocate bulk-read buffer
To avoid memory allocation failure during bulk-read, pre-allocate
a bulk-read buffer, so that if there is only one bulk-reader at
a time, it would just use the pre-allocated buffer and would not
do any memory allocation. However, if there are more than 1 bulk-
reader, then only one reader would use the pre-allocated buffer,
while the other reader would allocate the buffer for itself.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-11-21 18:59:33 +02:00
Artem Bityutskiy
6c0c42cdfd UBIFS: do not allocate too much
Bulk-read allocates 128KiB or more using kmalloc. The allocation
starts failing often when the memory gets fragmented. UBIFS still
works fine in this case, because it falls-back to standard
(non-optimized) read method, though. This patch teaches bulk-read
to allocate exactly the amount of memory it needs, instead of
allocating 128KiB every time.

This patch is also a preparation to the further fix where we'll
have a pre-allocated bulk-read buffer as well. For example, now
the @bu object is prepared in 'ubifs_bulk_read()', so we could
path either pre-allocated or allocated information to
'ubifs_do_bulk_read()' later. Or teaching 'ubifs_do_bulk_read()'
not to allocate 'bu->buf' if it is already there.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-11-21 18:59:25 +02:00
Artem Bityutskiy
39ce81ce71 UBIFS: do not print scary memory allocation warnings
Bulk-read allocates a lot of memory with 'kmalloc()', and when it
is/gets fragmented 'kmalloc()' fails with a scarry warning. But
because bulk-read is just an optimization, UBIFS keeps working fine.
Supress the warning by passing __GFP_NOWARN option to 'kmalloc()'.

This patch also introduces a macro for the magic 128KiB constant.
This is just neater.

Note, this is not really fixes the problem we had, but just hides
the warnings. The further patches fix the problem.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-11-21 18:59:16 +02:00
Linus Torvalds
0cb39aa0ac 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] Do not attempt to close invalidated file handles
  [CIFS] fix check for dead tcon in smb_init
2008-11-20 13:14:16 -08:00
Steve French
ddb4cbfc53 [CIFS] Do not attempt to close invalidated file handles
If a connection with open file handles has gone down
and come back up and reconnected without reopening
the file handle yet, do not attempt to send an SMB close
request for this handle in cifs_close.  We were
checking for the connection being invalid in cifs_close
but since the connection may have been reconnected
we also need to check whether the file handle
was marked invalid (otherwise we could close the
wrong file handle by accident).

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-20 20:14:13 +00:00
WANG Cong
ea7e743e49 hostfs: fix a duplicated global function name
fs/hostfs/hostfs_user.c defines do_readlink() as non-static, and so does
fs/xfs/linux-2.6/xfs_ioctl.c when CONFIG_XFS_DEBUG=y.  So rename
do_readlink() in hostfs to hostfs_do_readlink().

I think it's better if XFS guys will also rename their do_readlink(),
it's not necessary to use such a general name.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:50:00 -08:00
Hugh Dickins
f9454548e1 don't unlink an active swapfile
Peter Cordes is sorry that he rm'ed his swapfiles while they were in use,
he then had no pathname to swapoff.  It's a curious little oversight, but
not one worth a lot of hackery.  Kudos to Willy Tarreau for turning this
around from a discussion of synthetic pathnames to how to prevent unlink.
Mimic immutable: prohibit unlinking an active swapfile in may_delete()
(and don't worry my little head over the tiny race window).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Willy Tarreau <w@1wt.eu>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Peter Cordes <peter@cordes.ca>
Cc: Bodo Eggert <7eggert@gmx.de>
Cc: David Newall <davidn@davidnewall.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:59 -08:00
Michael Halcrow
ac97b9f9a2 eCryptfs: Allocate up to two scatterlists for crypto ops on keys
I have received some reports of out-of-memory errors on some older AMD
architectures.  These errors are what I would expect to see if
crypt_stat->key were split between two separate pages.  eCryptfs should
not assume that any of the memory sent through virt_to_scatterlist() is
all contained in a single page, and so this patch allocates two
scatterlist structs instead of one when processing keys.  I have received
confirmation from one person affected by this bug that this patch resolves
the issue for him, and so I am submitting it for inclusion in a future
stable release.

Note that virt_to_scatterlist() runs sg_init_table() on the scatterlist
structs passed to it, so the calls to sg_init_table() in
decrypt_passphrase_encrypted_session_key() are redundant.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Reported-by: Paulo J. S. Silva <pjssilva@ime.usp.br>
Cc: "Leon Woestenberg" <leon.woestenberg@gmail.com>
Cc: Tim Gardner <tim.gardner@canonical.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:58 -08:00
Steve French
bfb59820ee [CIFS] fix check for dead tcon in smb_init
This was recently changed to check for need_reconnect, but should
actually be a check for a tidStatus of CifsExiting.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-18 16:33:48 +00:00
Tejun Heo
55e8e30c38 block/md: fix md autodetection
Block ext devt conversion missed md_autodetect_dev() call in
rescan_partitions() leaving md autodetect unable to see partitions.
Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-11-18 15:08:56 +01:00
Tejun Heo
ba32929a91 block: make add_partition() return pointer to hd_struct
Make add_partition() return pointer to the new hd_struct on success
and ERR_PTR() value on failure.  This change will be used to fix md
autodetection bug.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-11-18 15:08:56 +01:00
Tejun Heo
eb60fa1066 block: fix add_partition() error path
Partition stats structure was not freed on devt allocation failure
path.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-11-18 15:08:55 +01:00
Linus Torvalds
4e14e833ac 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:
  prevent cifs_writepages() from skipping unwritten pages
  Fixed parsing of mount options when doing DFS submount
  [CIFS] Fix check for tcon seal setting and fix oops on failed mount from earlier patch
  [CIFS] Fix build break
  cifs: reinstate sharing of tree connections
  [CIFS] minor cleanup to cifs_mount
  cifs: reinstate sharing of SMB sessions sans races
  cifs: disable sharing session and tcon and add new TCP sharing code
  [CIFS] clean up server protocol handling
  [CIFS] remove unused list, add new cifs sock list to prepare for mount/umount fix
  [CIFS] Fix cifs reconnection flags
  [CIFS] Can't rely on iov length and base when kernel_recvmsg returns error
2008-11-17 20:53:31 -08:00
Dave Kleikamp
b066a48c95 prevent cifs_writepages() from skipping unwritten pages
Fixes a data corruption under heavy stress in which pages could be left
dirty after all open instances of a inode have been closed.

In order to write contiguous pages whenever possible, cifs_writepages()
asks pagevec_lookup_tag() for more pages than it may write at one time.
Normally, it then resets index just past the last page written before calling
pagevec_lookup_tag() again.

If cifs_writepages() can't write the first page returned, it wasn't resetting
index, and the next call to pagevec_lookup_tag() resulted in skipping all of
the pages it previously returned, even though cifs_writepages() did nothing
with them.  This can result in data loss when the file descriptor is about
to be closed.

This patch ensures that index gets set back to the next returned page so
that none get skipped.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Shirish S Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-18 04:30:07 +00:00
Igor Mammedov
2c55608f28 Fixed parsing of mount options when doing DFS submount
Since these hit the same routines, and are relatively small, it is easier to review
them as one patch.

Fixed incorrect handling of the last option in some cases
Fixed prefixpath handling convert path_consumed into host depended string length (in bytes)
Use non default separator if it is provided in the original mount options

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-18 04:29:06 +00:00
Steve French
ab3f992983 [CIFS] Fix check for tcon seal setting and fix oops on failed mount from earlier patch
set tcon->ses earlier

If the inital tree connect fails, we'll end up calling cifs_put_smb_ses
with a NULL pointer. Fix it by setting the tcon->ses earlier.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-17 16:03:00 +00:00
Steve French
c2b3382cd4 [CIFS] Fix build break
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-17 03:57:13 +00:00
Jeff Layton
f1987b44f6 cifs: reinstate sharing of tree connections
Use a similar approach to the SMB session sharing. Add a list of tcons
attached to each SMB session. Move the refcount to non-atomic. Protect
all of the above with the cifs_tcp_ses_lock. Add functions to
properly find and put references to the tcons.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-17 03:14:12 +00:00
Al Viro
5c06fe772d Fix broken ownership of /proc/sys/ files
D'oh...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reported-and-tested-by: Peter Palfrader <peter@palfrader.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-16 15:09:52 -08:00
Al Viro
8f7b0ba1c8 Fix inotify watch removal/umount races
Inotify watch removals suck violently.

To kick the watch out we need (in this order) inode->inotify_mutex and
ih->mutex.  That's fine if we have a hold on inode; however, for all
other cases we need to make damn sure we don't race with umount.  We can
*NOT* just grab a reference to a watch - inotify_unmount_inodes() will
happily sail past it and we'll end with reference to inode potentially
outliving its superblock.

Ideally we just want to grab an active reference to superblock if we
can; that will make sure we won't go into inotify_umount_inodes() until
we are done.  Cleanup is just deactivate_super().

However, that leaves a messy case - what if we *are* racing with
umount() and active references to superblock can't be acquired anymore?
We can bump ->s_count, grab ->s_umount, which will almost certainly wait
until the superblock is shut down and the watch in question is pining
for fjords.  That's fine, but there is a problem - we might have hit the
window between ->s_active getting to 0 / ->s_count - below S_BIAS (i.e.
the moment when superblock is past the point of no return and is heading
for shutdown) and the moment when deactivate_super() acquires
->s_umount.

We could just do drop_super() yield() and retry, but that's rather
antisocial and this stuff is luser-triggerable.  OTOH, having grabbed
->s_umount and having found that we'd got there first (i.e.  that
->s_root is non-NULL) we know that we won't race with
inotify_umount_inodes().

So we could grab a reference to watch and do the rest as above, just
with drop_super() instead of deactivate_super(), right? Wrong.  We had
to drop ih->mutex before we could grab ->s_umount.  So the watch
could've been gone already.

That still can be dealt with - we need to save watch->wd, do idr_find()
and compare its result with our pointer.  If they match, we either have
the damn thing still alive or we'd lost not one but two races at once,
the watch had been killed and a new one got created with the same ->wd
at the same address.  That couldn't have happened in inotify_destroy(),
but inotify_rm_wd() could run into that.  Still, "new one got created"
is not a problem - we have every right to kill it or leave it alone,
whatever's more convenient.

So we can use idr_find(...) == watch && watch->inode->i_sb == sb as
"grab it and kill it" check.  If it's been our original watch, we are
fine, if it's a newcomer - nevermind, just pretend that we'd won the
race and kill the fscker anyway; we are safe since we know that its
superblock won't be going away.

And yes, this is far beyond mere "not very pretty"; so's the entire
concept of inotify to start with.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-15 12:26:44 -08:00
Steve French
d82c2df54e [CIFS] minor cleanup to cifs_mount
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-15 00:07:26 +00:00
Jeff Layton
14fbf50d69 cifs: reinstate sharing of SMB sessions sans races
We do this by abandoning the global list of SMB sessions and instead
moving to a per-server list. This entails adding a new list head to the
TCP_Server_Info struct. The refcounting for the cifsSesInfo is moved to
a non-atomic variable. We have to protect it by a lock anyway, so there's
no benefit to making it an atomic. The list and refcount are protected
by the global cifs_tcp_ses_lock.

The patch also adds a new routines to find and put SMB sessions and
that properly take and put references under the lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-14 23:56:55 +00:00
Jeff Layton
e7ddee9037 cifs: disable sharing session and tcon and add new TCP sharing code
The code that allows these structs to be shared is extremely racy.
Disable the sharing of SMB and tcon structs for now until we can
come up with a way to do this that's race free.

We want to continue to share TCP sessions, however since they are
required for multiuser mounts. For that, implement a new (hopefully
race-free) scheme. Add a new global list of TCP sessions, and take
care to get a reference to it whenever we're dealing with one.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-14 23:42:32 +00:00
Steve French
3ec332ef7a [CIFS] clean up server protocol handling
We're currently declaring both a sockaddr_in and sockaddr6_in on the
stack, but we really only need storage for one of them. Declare a
sockaddr struct and cast it to the proper type. Also, eliminate the
protocolType field in the TCP_Server_Info struct. It's redundant since
we have a sa_family field in the sockaddr anyway.

We may need to revisit this if SCTP is ever implemented, but for now
this will simplify the code.

CIFS over IPv6 also has a number of problems currently. This fixes all
of them that I found. Eventually, it would be nice to move more of the
code to be protocol independent, but this is a start.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-14 03:35:10 +00:00
Steve French
fb39601664 [CIFS] remove unused list, add new cifs sock list to prepare for mount/umount fix
Also adds two lines missing from the previous patch (for the need reconnect flag in the
/proc/fs/cifs/DebugData handling)

The new global_cifs_sock_list is added, and initialized in init_cifs but not used yet.
Jeff Layton will be adding code in to use that and to remove the GlobalTcon and GlobalSMBSession
lists.

CC: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-13 20:04:07 +00:00
Linus Torvalds
7b42365396 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
  dlm: fix shutdown cleanup
2008-11-13 11:56:05 -08:00
Steve French
3b79521093 [CIFS] Fix cifs reconnection flags
In preparation for Jeff's big umount/mount fixes to remove the possibility of
various races in cifs mount and linked list handling of sessions, sockets and
tree connections, this patch cleans up some repetitive code in cifs_mount,
and addresses a problem with ses->status and tcon->tidStatus in which we
were overloading the "need_reconnect" state with other status in that
field.  So the "need_reconnect" flag has been broken out from those
two state fields (need reconnect was not mutually exclusive from some of the
other possible tid and ses states).  In addition, a few exit cases in
cifs_mount were cleaned up, and a problem with a tcon flag (for lease support)
was not being set consistently for the 2nd mount of the same share

CC: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-13 19:45:32 +00:00