The BKL is protecting nothing than two memory allocations here.
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The BKL is only used in put_super and fill_super that are both protected by
the superblocks s_umount rw_semaphore. Therefore it is safe to remove the
BKL entirely.
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The BKL is only used in put_super and fill_super that are both protected by
the superblocks s_umount rw_semaphore. Therefore it is safe to remove the BKL
entirely.
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The BKL is only used in put_super, fill_super and remount_fs that are all
three protected by the superblocks s_umount rw_semaphore. Therefore it is
safe to remove the BKL entirely.
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This patch is a preparation necessary to remove the BKL from do_new_mount().
It explicitly adds calls to lock_kernel()/unlock_kernel() around
get_sb/fill_super operations for filesystems that still uses the BKL.
I've read through all the code formerly covered by the BKL inside
do_kern_mount() and have satisfied myself that it doesn't need the BKL
any more.
do_kern_mount() is already called without the BKL when mounting the rootfs
and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called
from various places without BKL: simple_pin_fs(), nfs_do_clone_mount()
through nfs_follow_mountpoint(), afs_mntpt_do_automount() through
afs_mntpt_follow_link(). Both later functions are actually the filesystems
follow_link inode operation. vfs_kern_mount() is calling the specified
get_sb function and lets the filesystem do its job by calling the given
fill_super function.
Therefore I think it is safe to push down the BKL from the VFS to the
low-level filesystems get_sb/fill_super operation.
[arnd: do not add the BKL to those file systems that already
don't use it elsewhere]
Signed-off-by: Jan Blunck <jblunck@infradead.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Christoph Hellwig <hch@infradead.org>
We currently use struct backing_dev_info for various different purposes.
Originally it was introduced to describe a backing device which includes
an unplug and congestion function and various bits of readahead information
and VM-relevant flags. We're also using for tracking dirty inodes for
writeback.
To make writeback properly find all inodes we need to only access the
per-filesystem backing_device pointed to by the superblock in ->s_bdi
inside the writeback code, and not the instances pointeded to by
inode->i_mapping->backing_dev which can be overriden by special devices
or might not be set at all by some filesystems.
Long term we should split out the writeback-relevant bits of struct
backing_device_info (which includes more than the current bdi_writeback)
and only point to it from the superblock while leaving the traditional
backing device as a separate structure that can be overriden by devices.
The one exception for now is the block device filesystem which really
wants different writeback contexts for it's different (internal) inodes
to handle the writeout more efficiently. For now we do this with
a hack in fs-writeback.c because we're so late in the cycle, but in
the future I plan to replace this with a superblock method that allows
for multiple writeback contexts per filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
fs/fuse/dev.c:1357: warning: ‘total_len’ may be used uninitialized in this
function
Initialize total_len to zero, else its value will be undefined.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
cifs: prevent infinite recursion in cifs_reconnect_tcon
cifs: set backing_dev_info on new S_ISREG inodes
Having the limits file world readable will ease the task of system
management on systems where root privileges might be restricted.
Having admin restricted with root priviledges, he/she could not check
other users process' limits.
Also it'd align with most of the /proc stat files.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Eugene Teo <eugene@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cifs_reconnect_tcon is called from smb_init. After a successful
reconnect, cifs_reconnect_tcon will call reset_cifs_unix_caps. That
function will, in turn call CIFSSMBQFSUnixInfo and CIFSSMBSetFSUnixInfo.
Those functions also call smb_init.
It's possible for the session and tcon reconnect to succeed, and then
for another cifs_reconnect to occur before CIFSSMBQFSUnixInfo or
CIFSSMBSetFSUnixInfo to be called. That'll cause those functions to call
smb_init and cifs_reconnect_tcon again, ad infinitum...
Break the infinite recursion by having those functions use a new
smb_init variant that doesn't attempt to perform a reconnect.
Reported-and-Tested-by: Michal Suchanek <hramrach@centrum.cz>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When renaming over a directory we need to use hfsplus_rmdir instead of
hfsplus_unlink to evict the victim. This makes sure we properly error out
on non-empty directory as required by Posix (BZ #16571), and it also makes
sure we do the right thing in case i_nlink will every be set correctly for
directories on hfsplus.
Reported-by: Vlado Plaga <rechner@vlado-do.de>
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Most of the extent handling code already does proper SMP locking, but
hfsplus_write_inode was calling into hfsplus_ext_write_extent without
taking the extents_lock. Fix this by splitting hfsplus_ext_write_extent
into an internal helper that expects the lock, and a public interface
that first acquires it.
Also add a few locking asserts and document the locking rules in
hfsplus_fs.h.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
We already have i_mutex for readdir and the namespace operations that add
entries to open_dir_list, the only thing that was missing was the removal
in hfsplus_dir_release.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
The flags in the HFS+-specific superlock do get modified during runtime,
use atomic bitops to make the modifications SMP safe.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Lock updates to the mutal fields in the volume header, and document the
locing in the hfsplus_sb_info structure.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
We never walk the list - the only reason for it is to make the resource fork
inodes appear hashed to the writeback code. Borrow a trick from JFS to do
that without needing a list head.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
We never look at it, nor change the next_alloc field in the superblock. So
don't bother caching it or writing it out in hfsplus_sync_fs.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Add a new hfsplus_system_write_inode for writing the special system inodes
and streamline the fastpath write_inode code.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Add a new hfsplus_system_read_inode for reading the special system inodes
and streamline the fastpath iget code.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
HFSPLUS_I doesn't return a pointer to the hfsplus-specific inode
information like all other FOO_I macros, but dereference the pointer in a way
that made it look like a direct struct derefence. This only works as long
as the HFSPLUS_I macro is used directly and prevents us from keepig a local
hfsplus_inode_info pointer. Fix the calling convention and introduce a local
hip variable in all functions that use it constantly.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
HFSPLUS_SB doesn't return a pointer to the hfsplus-specific superblock
information like all other FOO_SB macros, but dereference the pointer in a way
that made it look like a direct struct derefence. This only works as long
as the HFSPLUS_SB macro is used directly and prevents us from keepig a local
hfsplus_sb_info pointer. Fix the calling convention and introduce a local
sbi variable in all functions that use it constantly.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Except for ->put_super the BKL is now gone from HFS, which means it's
superflous there too as ->put_super is serialized by the VFS.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Use alloc_mutex to protect hfsplus_sync_fs against itself and concurrent
allocations, which allows to get rid of lock_super in hfsplus.
Note that most fields in the superblock still aren't protected against
concurrent allocations, that will follow later.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Use a new per-sb alloc_mutex instead of abusing i_mutex of the alloc_file
to protect block allocations. This gets rid of lockdep nesting warnings
and prepares for extending the scope of alloc_mutex.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Use i_mutex for protecting against concurrent setflags ioctls like in
other filesystems and get rid of the BKL in hfsplus_ioctl.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Currenly the HFSPLUS_IOC_EXT2_GETFLAGS case never unlocks the BKL, which
can lead to easily reproduced lockups when doing multiple GETFLAGS ioctls.
Fix this by only taking the BKL for the HFSPLUS_IOC_EXT2_SETFLAGS case
as neither HFSPLUS_IOC_EXT2_GETFLAGS not the default error case needs it.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
This patch fixes a GFS2 problem whereby the first rename after a
mount can result in a file system consistency error being flagged
improperly and cause the file system to withdraw. The problem is
that the rename code tries to run the rgrp list with function
gfs2_blk2rgrpd before the rgrp list is guaranteed to be read in
from disk. The patch makes the rename function hold the rindex
glock (as the gfs2_unlink code does today) which reads in the rgrp
list if need be. There were a total of three places in the rename
code that improperly referenced the rgrp list without the rindex
glock and this patch fixes all three.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
ocfs2 fast symlinks are NUL terminated strings stored inline in the
inode data area. However, disk corruption or a local attacker could, in
theory, remove that NUL. Because we're using strlen() (my fault,
introduced in a731d1 when removing vfs_follow_link()), we could walk off
the end of that string.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Cc: stable@kernel.org
Testing on very recent kernel (2.6.36-rc6) made this warning pop:
WARNING: at fs/fs-writeback.c:87 inode_to_bdi+0x65/0x70()
Hardware name:
Dirtiable inode bdi default != sb bdi cifs
...the following patch fixes it and seems to be the obviously correct
thing to do for cifs.
Cc: stable@kernel.org
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Get a reference to the file early so we can eventually base the decision
about signing on the correct tcon. If that doesn't work for some reason,
then fall back to generic_writepages. That's just as likely to fail, but
it simplifies the error handling.
In truth, I'm not sure how that could occur anyway, so maybe a NULL
open_file here ought to be a BUG()?
After that, we drop the reference to the open_file and then we re-get
one prior to each WriteAndX call. This helps ensure that the filehandle
isn't held open any longer than necessary and that open files are
reclaimed prior to each write call.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
To minimize calls to cifs_sb_tcon and to allow for a clear error path if
a tcon can't be acquired.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
At mount time, we'll always need to create a tcon that will serve as a
template for others that are associated with the mount. This tcon is
known as the "master" tcon.
In some cases, we'll need to use that tcon regardless of who's accessing
the mount. Add an accessor function for the master tcon and go ahead and
switch the appropriate places to use it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When we convert cifs to do multiple sessions per mount, we'll need more
than one tcon per superblock. At that point "cifs_sb->tcon" will make
no sense. Add a new accessor function that gets a tcon given a cifs_sb.
For now, it just returns cifs_sb->tcon. Later it'll do more.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
If registering fs cache failed, we weren't cleaning up proc.
Acked-by: Jeff Layton <jlayton@redhat.com>
CC: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
With commit 7332f2a621, cifsd will no
longer exit when the socket abends and the tcpStatus is CifsNew. With
that change, there's no reason to avoid matching an existing session in
this state.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Eventually, we'll have more than one tcon per superblock. At that point,
we'll need to know which one is associated with a particular fid. For
now, this is just set from the cifs_sb->tcon pointer, but eventually
the caller of cifs_new_fileinfo will pass a tcon pointer in.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
If configured, Minshall+French Symlinks are used against
all servers. If the server supports UNIX Extensions,
we still create Minshall+French Symlinks on write,
but on read we fallback to UNIX Extension symlinks.
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
