Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or
anything else, so that the filesystem can track internally if it
needs to push out a transaction for fdatasync or not.
This is just the prototype change with no user for it yet. I plan
to push large XFS changes for the next merge window, and getting
this trivial infrastructure in this window would help a lot to avoid
tree interdependencies.
Also remove incorrect comments that ->dirty_inode can't block. That
has been changed a long time ago, and many implementations rely on it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem:
xen: cleancache shim to Xen Transcendent Memory
ocfs2: add cleancache support
ext4: add cleancache support
btrfs: add cleancache support
ext3: add cleancache support
mm/fs: add hooks to support cleancache
mm: cleancache core ops functions and config
fs: add field to superblock to support cleancache
mm/fs: cleancache documentation
Fix up trivial conflict in fs/btrfs/extent_io.c due to includes
This fifth patch of eight in this cleancache series "opts-in"
cleancache for ext3. Filesystems must explicitly enable
cleancache by calling cleancache_init_fs anytime an instance
of the filesystem is mounted. For ext3, all other cleancache
hooks are in the VFS layer including the matching cleancache_flush_fs
hook which must be called on unmount.
Details and a FAQ can be found in Documentation/vm/cleancache.txt
[v6-v8: no changes]
[v5: jeremy@goop.org: simplify init hook and any future fs init changes]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy@goop.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Andreas Dilger <adilger@sun.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik Van Riel <riel@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
When make_indexed_dir() fails (e.g. because of ENOSPC) after it has allocated
block for index tree root, we did not properly mark all changed buffers dirty.
This lead to only some of these buffers being written out and thus effectively
corrupting the directory.
Fix the issue by marking all changed data dirty even in the error failure case.
CC: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
ext3_symlink() cannot call __page_symlink() with transaction open.
__page_symlink() calls ext3_write_begin() which gets page lock which ranks
above transaction start (thus lock ordering is violated) and and also
ext3_write_begin() waits for a transaction commit when we run out of space
which never happens if we hold transaction open.
Fix the problem by stopping a transaction before calling __page_symlink()
(we have to be careful and put inode to orphan list so that it gets deleted
in case of crash) and starting another one after __page_symlink() returns
for addition of symlink into a directory.
Signed-off-by: Jan Kara <jack@suse.cz>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
quota: Don't write quota info in dquot_commit()
ext3: Fix writepage credits computation for ordered mode
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
Documentation/iostats.txt: bit-size reference etc.
cfq-iosched: removing unnecessary think time checking
cfq-iosched: Don't clear queue stats when preempt.
blk-throttle: Reset group slice when limits are changed
blk-cgroup: Only give unaccounted_time under debug
cfq-iosched: Don't set active queue in preempt
block: fix non-atomic access to genhd inflight structures
block: attempt to merge with existing requests on plug flush
block: NULL dereference on error path in __blkdev_get()
cfq-iosched: Don't update group weights when on service tree
fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away
block: Require subsystems to explicitly allocate bio_set integrity mempool
jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
fs: make fsync_buffers_list() plug
mm: make generic_writepages() use plugging
blk-cgroup: Add unaccounted time to timeslice_used.
block: fixup plugging stubs for !CONFIG_BLOCK
block: remove obsolete comments for blkdev_issue_zeroout.
blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.
...
Fix up conflicts in fs/{aio.c,super.c}
Original computation forgets to count writes of indirect block themselves
(it only counts with blocks necessary for their allocation) in ordered mode.
Acked-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by:Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
And give it a kernel-doc comment.
[akpm@linux-foundation.org: btrfs changed in linux-next]
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
ext3: Always set dx_node's fake_dirent explicitly.
ext3: Fix an overflow in ext3_trim_fs.
jbd: Remove one to many n's in a word.
ext3: skip orphan cleanup on rocompat fs
ext2: Fix link count corruption under heavy link+rename load
ext3: speed up group trim with the right free block count.
ext3: Adjust trim start with first_data_block.
quota: return -ENOMEM when memory allocation fails
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (33 commits)
AppArmor: kill unused macros in lsm.c
AppArmor: cleanup generated files correctly
KEYS: Add an iovec version of KEYCTL_INSTANTIATE
KEYS: Add a new keyctl op to reject a key with a specified error code
KEYS: Add a key type op to permit the key description to be vetted
KEYS: Add an RCU payload dereference macro
AppArmor: Cleanup make file to remove cruft and make it easier to read
SELinux: implement the new sb_remount LSM hook
LSM: Pass -o remount options to the LSM
SELinux: Compute SID for the newly created socket
SELinux: Socket retains creator role and MLS attribute
SELinux: Auto-generate security_is_socket_class
TOMOYO: Fix memory leak upon file open.
Revert "selinux: simplify ioctl checking"
selinux: drop unused packet flow permissions
selinux: Fix packet forwarding checks on postrouting
selinux: Fix wrong checks for selinux_policycap_netpeer
selinux: Fix check for xfrm selinux context algorithm
ima: remove unnecessary call to ima_must_measure
IMA: remove IMA imbalance checking
...
File system UUID is made available to application
via /proc/<pid>/mountinfo
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that VFS check for inode->i_nlink == 0 and returns proper
error, remove similar check from file system
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
(crossport of 1f7bebb9e9
by Andreas Schlick <schlick@lavabit.com>)
When ext3_dx_add_entry() has to split an index node, it has to ensure that
name_len of dx_node's fake_dirent is also zero, because otherwise e2fsck
won't recognise it as an intermediate htree node and consider the htree to
be corrupted.
CC: stable@kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
In a bs=4096 volume, if we call FITRIM with the following parameter as
fstrim_range(start = 102400, len = 134144000, minlen = 10240), with the
following code:
if (len >= EXT3_BLOCKS_PER_GROUP(sb))
len -= (EXT3_BLOCKS_PER_GROUP(sb) - first_block);
else
last_block = first_block + len;
So if len < EXT3_BLOCKS_PER_GROUP while first_block + len >
EXT3_BLOCKS_PER_GROUP, last_block will be set to an overflow value
which exceeds EXT3_BLOCKS_PER_GROUP.
This patch fixes it and adjusts len and last_block accordingly.
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Orphan cleanup is currently executed even if the file system has some
number of unknown ROCOMPAT features, which deletes inodes and frees
blocks, which could be very bad for some RO_COMPAT features.
This patch skips the orphan cleanup if it contains readonly compatible
features not known by this ext3 implementation, which would prevent
the fs from being mounted (or remounted) readwrite.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: Jan Kara <jack@suse.cz>
When we trim some free blocks in a group of ext3, we should
calculate the free blocks properly and check whether there are
enough freed blocks left for us to trim. Current solution will
only calculate free spaces if they are large for a trim which
is wrong.
Let us see a small example:
a group has 1.5M free which are 300k, 300k, 300k, 300k, 300k.
And minblocks is 1M. With current solution, we have to iterate
the whole group since these 300k will never be subtracted from
1.5M. But actually we should exit after we find the first 2
free spaces since the left 3 chunks only sum up to 900K if we
subtract the first 600K although they can't be trimed.
Cc: Jan Kara <jack@suse.cz>
Cc: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
As we have make the consense in the e-mail[1], the trim start should
be added with first_data_block. So this patch fulfill it and remove
the check for start < first_data_block.
[1] http://www.spinics.net/lists/linux-ext4/msg22737.html
Cc: Jan Kara <jack@suse.cz>
Cc: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
SELinux would like to implement a new labeling behavior of newly created
inodes. We currently label new inodes based on the parent and the creating
process. This new behavior would also take into account the name of the
new object when deciding the new label. This is not the (supposed) full path,
just the last component of the path.
This is very useful because creating /etc/shadow is different than creating
/etc/passwd but the kernel hooks are unable to differentiate these
operations. We currently require that userspace realize it is doing some
difficult operation like that and than userspace jumps through SELinux hoops
to get things set up correctly. This patch does not implement new
behavior, that is obviously contained in a seperate SELinux patch, but it
does pass the needed name down to the correct LSM hook. If no such name
exists it is fine to pass NULL.
Signed-off-by: Eric Paris <eparis@redhat.com>
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
block: ensure that completion error gets properly traced
blktrace: add missing probe argument to block_bio_complete
block cfq: don't use atomic_t for cfq_group
block cfq: don't use atomic_t for cfq_queue
block: trace event block fix unassigned field
block: add internal hd part table references
block: fix accounting bug on cross partition merges
kref: add kref_test_and_get
bio-integrity: mark kintegrityd_wq highpri and CPU intensive
block: make kblockd_workqueue smarter
Revert "sd: implement sd_check_events()"
block: Clean up exit_io_context() source code.
Fix compile warnings due to missing removal of a 'ret' variable
fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
cfq-iosched: don't check cfqg in choose_service_tree()
fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
cdrom: export cdrom_check_events()
sd: implement sd_check_events()
sr: implement sr_check_events()
...
As Al Viro pointed out path resolution during Q_QUOTAON calls to quotactl
is prone to deadlocks. We hold s_umount semaphore for reading during the
path resolution and resolution itself may need to acquire the semaphore
for writing when e. g. autofs mountpoint is passed.
Solve the problem by performing the resolution before we get hold of the
superblock (and thus s_umount semaphore). The whole thing is complicated
by the fact that some filesystems (OCFS2) ignore the path argument. So to
distinguish between filesystem which want the path and which do not we
introduce new .quota_on_meta callback which does not get the path. OCFS2
then uses this callback instead of old .quota_on.
CC: Al Viro <viro@ZenIV.linux.org.uk>
CC: Christoph Hellwig <hch@lst.de>
CC: Ted Ts'o <tytso@mit.edu>
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits)
ext4: fix trimming starting with block 0 with small blocksize
ext4: revert buggy trim overflow patch
ext4: don't pass entire map to check_eofblocks_fl
ext4: fix memory leak in ext4_free_branches
ext4: remove ext4_mb_return_to_preallocation()
ext4: flush the i_completed_io_list during ext4_truncate
ext4: add error checking to calls to ext4_handle_dirty_metadata()
ext4: fix trimming of a single group
ext4: fix uninitialized variable in ext4_register_li_request
ext4: dynamically allocate the jbd2_inode in ext4_inode_info as necessary
ext4: drop i_state_flags on architectures with 64-bit longs
ext4: reorder ext4_inode_info structure elements to remove unneeded padding
ext4: drop ec_type from the ext4_ext_cache structure
ext4: use ext4_lblk_t instead of sector_t for logical blocks
ext4: replace i_delalloc_reserved_flag with EXT4_STATE_DELALLOC_RESERVED
ext4: fix 32bit overflow in ext4_ext_find_goal()
ext4: add more error checks to ext4_mkdir()
ext4: ext4_ext_migrate should use NULL not 0
ext4: Use ext4_error_file() to print the pathname to the corrupted inode
ext4: use IS_ERR() to check for errors in ext4_error_file
...
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
ext2: Resolve 'dereferencing pointer to incomplete type' when enabling EXT2_XATTR_DEBUG
ext3: Remove redundant unlikely()
ext2: Remove redundant unlikely()
ext3: speed up file creates by optimizing rec_len functions
ext2: speed up file creates by optimizing rec_len functions
ext3: Add more journal error check
ext3: Add journal error check in resize.c
quota: Use %pV and __attribute__((format (printf in __quota_error and fix fallout
ext3: Add FITRIM handling
ext3: Add batched discard support for ext3
ext3: Add journal error check into ext3_rename()
ext3: Use search_dirblock() in ext3_dx_find_entry()
ext3: Avoid uninitialized memory references with a corrupted htree directory
ext3: Return error code from generic_check_addressable
ext3: Add journal error check into ext3_delete_entry()
ext3: Add error check in ext3_mkdir()
fs/ext3/super.c: Use printf extension %pV
fs/ext2/super.c: Use printf extension %pV
ext3: don't update sb journal_devnum when RO dev
IS_ERR() already implies unlikely(), so it can be omitted here.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jan Kara <jack@suse.cz>
The addition of 64k block capability in the rec_len_from_disk
and rec_len_to_disk functions added a bit of math overhead which
slows down file create workloads needlessly when the architecture
cannot even support 64k blocks, thanks to page size limits.
Similar changes already exist in the ext4 codebase.
The directory entry checking can also be optimized a bit
by sprinkling in some unlikely() conditions to move the
error handling out of line.
bonnie++ sequential file creates on a 512MB ramdisk speeds up
from about 77,000/s to about 82,000/s, about a 6% improvement.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Check return value of ext3_journal_get_write_acccess() and
ext3_journal_dirty_metadata().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Check return value of ext3_journal_get_write_access() and
ext3_journal_dirty_metadata().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The ioctl takes fstrim_range structure (defined in include/linux/fs.h) as an
argument specifying a range of filesystem to trim and the minimum size of an
continguous extent to trim. After the FITRIM is done, the number of bytes
passed from the filesystem down the block stack to the device for potential
discard is stored in fstrim_range.len. This number is a maximum discard amount
from the storage device's perspective, because FITRIM called repeatedly will
keep sending the same sectors for discard. fstrim_range.len will report the
same potential discard bytes each time, but only sectors which had been written
to between the discards would actually be discarded by the storage device.
Further, the kernel block layer reserves the right to adjust the discard ranges
to fit raid stripe geometry, non-trim capable devices in a LVM setup, etc.
These reductions would not be reflected in fstrim_range.len.
Thus fstrim_range.len can give the user better insight on how much storage
space has potentially been released for wear-leveling, but it needs to be one
of only one criteria the userspace tools take into account when trying to
optimize calls to FITRIM.
Thanks to Greg Freemyer <greg.freemyer@gmail.com> for better commit message.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Walk through allocation groups and trim all free extents. It can be
invoked through FITRIM ioctl on the file system. The main idea is to
provide a way to trim the whole file system if needed, since some SSD's
may suffer from performance loss after the whole device was filled (it
does not mean that fs is full!).
It search for free extents in allocation groups specified by Byte range
start -> start+len. When the free extent is within this range, blocks are
marked as used and then trimmed. Afterwards these blocks are marked as
free in per-group bitmap.
[JK: Fixed up error handling and trimming of a single group]
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
This simple implementation just checks for no ACLs on the inode, and
if so, then the rcu-walk may proceed, otherwise fail it.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
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>
Check return value of ext3_journal_get_write_access() and
ext3_journal_dirty_metadata().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Use the search_dirblock() in ext3_dx_find_entry(). It makes the code
easier to read, and it takes advantage of common code. It also saves
100 bytes or so of text space.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Jan Kara <jack@suse.cz>
If the first htree directory is missing '.' or '..' but is otherwise a
valid directory, and we do a lookup for '.' or '..', it's possible to
dereference an uninitialized memory pointer in ext3_htree_next_block().
Avoid this.
We avoid this by moving the special case from ext3_dx_find_entry() to
ext3_find_entry(); this also means we can optimize ext3_find_entry()
slightly when NFS looks up "..".
Thanks to Brad Spengler for pointing a Clang warning that led me to
look more closely at this code. The warning was harmless, but it was
useful in pointing out code that was too ugly to live. This warning was
also reported by Roman Borisov.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Jan Kara <jack@suse.cz>
ext3_fill_super should return the error code that generic_check_accessible
returns when an error condition occurs.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Check return value of ext3_journal_get_write_access() and
ext3_journal_dirty_metadata().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Check return value of ext3_journal_get_write_access, ext3_journal_dirty_metadata
and ext3_mark_inode_dirty. Consolidate error path under new label 'out_clear_inode'
and adjust bh releasing appropriately.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Using %pV reduces the number of printk calls and
eliminates any possible message interleaving from
other printk calls.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jan Kara <jack@suse.cz>
An ext3 filesystem on a read-only device, with an external journal
which is at a different device number then recorded in the superblock
will fail to honor the read-only setting of the device and trigger
a superblock update (write).
For example:
- ext3 on a software raid which is in read-only mode
- external journal on a read-write device which has changed device num
- attempt to mount with -o journal_dev=<new_number>
- hits BUG_ON(mddev->ro = 1) in md.c
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After recent blkdev_get() modifications, open_by_devnum() and
open_bdev_exclusive() are simple wrappers around blkdev_get().
Replace them with blkdev_get_by_dev() and blkdev_get_by_path().
blkdev_get_by_dev() is identical to open_by_devnum().
blkdev_get_by_path() is slightly different in that it doesn't
automatically add %FMODE_EXCL to @mode.
All users are converted. Most conversions are mechanical and don't
introduce any behavior difference. There are several exceptions.
* btrfs now sets FMODE_EXCL in btrfs_device->mode, so there's no
reason to OR it explicitly on blkdev_put().
* gfs2, nilfs2 and the generic mount_bdev() now set FMODE_EXCL in
sb->s_mode.
* With the above changes, sb->s_mode now always should contain
FMODE_EXCL. WARN_ON_ONCE() added to kill_block_super() to detect
errors.
The new blkdev_get_*() functions are with proper docbook comments.
While at it, add function description to blkdev_get() too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Joern Engel <joern@lazybastard.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: reiserfs-devel@vger.kernel.org
Cc: xfs-masters@oss.sgi.com
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Over time, block layer has accumulated a set of APIs dealing with bdev
open, close, claim and release.
* blkdev_get/put() are the primary open and close functions.
* bd_claim/release() deal with exclusive open.
* open/close_bdev_exclusive() are combination of open and claim and
the other way around, respectively.
* bd_link/unlink_disk_holder() to create and remove holder/slave
symlinks.
* open_by_devnum() wraps bdget() + blkdev_get().
The interface is a bit confusing and the decoupling of open and claim
makes it impossible to properly guarantee exclusive access as
in-kernel open + claim sequence can disturb the existing exclusive
open even before the block layer knows the current open if for another
exclusive access. Reorganize the interface such that,
* blkdev_get() is extended to include exclusive access management.
@holder argument is added and, if is @FMODE_EXCL specified, it will
gain exclusive access atomically w.r.t. other exclusive accesses.
* blkdev_put() is similarly extended. It now takes @mode argument and
if @FMODE_EXCL is set, it releases an exclusive access. Also, when
the last exclusive claim is released, the holder/slave symlinks are
removed automatically.
* bd_claim/release() and close_bdev_exclusive() are no longer
necessary and either made static or removed.
* bd_link_disk_holder() remains the same but bd_unlink_disk_holder()
is no longer necessary and removed.
* open_bdev_exclusive() becomes a simple wrapper around lookup_bdev()
and blkdev_get(). It also has an unexpected extra bdev_read_only()
test which probably should be moved into blkdev_get().
* open_by_devnum() is modified to take @holder argument and pass it to
blkdev_get().
Most of bdev open/close operations are unified into blkdev_get/put()
and most exclusive accesses are tested atomically at the open time (as
it should). This cleans up code and removes some, both valid and
invalid, but unnecessary all the same, corner cases.
open_bdev_exclusive() and open_by_devnum() can use further cleanup -
rename to blkdev_get_by_path() and blkdev_get_by_devt() and drop
special features. Well, let's leave them for another day.
Most conversions are straight-forward. drbd conversion is a bit more
involved as there was some reordering, but the logic should stay the
same.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Brown <neilb@suse.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: dm-devel@redhat.com
Cc: drbd-dev@lists.linbit.com
Cc: Leo Chen <leochen@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Joern Engel <joern@logfs.org>
Cc: reiserfs-devel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (24 commits)
quota: Fix possible oops in __dquot_initialize()
ext3: Update kernel-doc comments
jbd/2: fixed typos
ext2: fixed typo.
ext3: Fix debug messages in ext3_group_extend()
jbd: Convert atomic_inc() to get_bh()
ext3: Remove misplaced BUFFER_TRACE() in ext3_truncate()
jbd: Fix debug message in do_get_write_access()
jbd: Check return value of __getblk()
ext3: Use DIV_ROUND_UP() on group desc block counting
ext3: Return proper error code on ext3_fill_super()
ext3: Remove unnecessary casts on bh->b_data
ext3: Cleanup ext3_setup_super()
quota: Fix issuing of warnings from dquot_transfer
quota: fix dquot_disable vs dquot_transfer race v2
jbd: Convert bitops to buffer fns
ext3/jbd: Avoid WARN() messages when failing to write the superblock
jbd: Use offset_in_page() instead of manual calculation
jbd: Remove unnecessary goto statement
jbd: Use printk_ratelimited() in journal_alloc_journal_head()
...
Christoph Hellwig