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: NJens Axboe <jaxboe@fusionio.com>

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: NNick Piggin <npiggin@kernel.dk>

Hi,

There's a small memory leak in fs/udf/namei.c::udf_find_entry().

We dynamically allocate memory for 'fname' with kmalloc() and in most
situations we free it before we leave the function, but there is one
situation where we do not (but should). This patch closes the leak by
jumping to the 'out_ok' label which does the correct cleanup rather than
doing half the cleanup and returning directly.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NJan Kara <jack@suse.cz>

If udf_bread() called from udf_add_entry() managed to merge created extent to
an already existing one (or if previous extents could be merged), the code
truncating the last extent to proper size would just overwrite the freshly
allocated extent with an extent that used to be in that place.  This obviously
results in a directory corruption. Fix the problem by properly reloading the
last extent.
Signed-off-by: NJan Kara <jack@suse.cz>

Code doing conversion from INICB file to a normal file in udf_file_aio_write()
is not protected by any lock from other code modifying the inode. Use
i_alloc_sem for that.
Reported-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NJan Kara <jack@suse.cz>

The udf_readdir(), udf_lookup(), udf_create(), udf_mknod(), udf_mkdir(),
udf_rmdir(), udf_link(), udf_get_parent() and udf_unlink() seems already
adequately protected by i_mutex held by VFS invoking calls. The udf_rename()
instead should be already protected by lock_rename again by VFS. The
udf_ioctl(), udf_fill_super() and udf_evict_inode() don't requires any further
protection.

This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NJan Kara <jack@suse.cz>

This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NJan Kara <jack@suse.cz>

Replace bkl with the UDF_I(inode)->i_data_sem rw semaphore in
udf_release_file(), udf_symlink(), udf_symlink_filler(), udf_get_block(),
udf_block_map(), and udf_setattr(). The rule now is that any operation
on regular file's or symlink's extents (or generally allocation information
including goal block) needs to hold i_data_sem.

This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NJan Kara <jack@suse.cz>

udf_count_free_bitmap() does not need BKL because bitmaps are in a fixed
place on disk and so we can count set bits without serialization.
udf_count_free_table() is now protected by s_alloc_mutex instead of BKL
to get a consistent view of free space extents.
Signed-off-by: NJan Kara <jack@suse.cz>

There's no need to call udf_add_free_space() for one block at a time. It saves
us noticeable amount of work and yields different result from the original
code only if the filesystem is corrupted and bitmap bit is already cleared.
In such case counter of free blocks is probably wrong anyways so the change
does not matter.
Signed-off-by: NJan Kara <jack@suse.cz>

udf_put_super() does not need BKL because the filesystem is shut down so
there's nothing to race with. The credential changes in udf_remount_fs()
and LVID changes are now protected by dedicated locks so we can remove BKL
from this function as well.
Signed-off-by: NJan Kara <jack@suse.cz>

Superblock carries credentials (uid, gid, etc.) which are used as default
values in __udf_read_inode() when media does not provide these. These
credentials can change during remount so we protect them by a rwlock so that
each inode gets a consistent set of credentials.
Signed-off-by: NJan Kara <jack@suse.cz>

udf_open_lvid() and udf_close_lvid() were modifying LVID without
s_alloc_mutex. Since they can be called from remount, the modification
could race with other filesystem modifications of LVID so protect them
by s_alloc_mutex just to be sure.
Signed-off-by: NJan Kara <jack@suse.cz>

uniqueID handling has been duplicated in three places. Move it into a common
helper. Since we modify an LVID buffer with uniqueID update, we take
sbi->s_alloc_mutex to protect agaist other modifications of the structure.
Signed-off-by: NJan Kara <jack@suse.cz>

udf_update_inode() does not need BKL since on-disk inode modifications are
protected by the buffer lock and reading of values of in-memory inode is
safe without any lock. In some cases we can write inconsistent inode state
to disk but in that case inode will be marked dirty and overwritten later.

Also make unnecessarily global udf_sync_inode() static.
Signed-off-by: NJan Kara <jack@suse.cz>

Use atomic bitops to manipulate with sb flags to make manipulation safe
without any locking.
Signed-off-by: NJan Kara <jack@suse.cz>

Add __attribute__((format... to udf_warning.

All arguments matched formats, no other changes necessary.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

... and switch of the obvious get_sb_bdev() users to ->mount()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Clones an existing reference to inode; caller must already hold one.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

With all the patches we have queued in the BKL removal tree, only a
few dozen modules are left that actually rely on the BKL, and even
there are lots of low-hanging fruit. We need to decide what to do
about them, this patch illustrates one of the options:

Every user of the BKL is marked as 'depends on BKL' in Kconfig,
and the CONFIG_BKL becomes a user-visible option. If it gets
disabled, no BKL using module can be built any more and the BKL
code itself is compiled out.

The one exception is file locking, which is practically always
enabled and does a 'select BKL' instead. This effectively forces
CONFIG_BKL to be enabled until we have solved the fs/lockd
mess and can apply the patch that removes the BKL from fs/locks.c.
Signed-off-by: NArnd 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: NJan Blunck <jblunck@infradead.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Christoph Hellwig <hch@infradead.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For the new truncate sequence every filesystem that wants to truncate on-disk
state needs a seattr method.  Convert the remaining filesystems that implement
the truncate inode operation to have its own setattr method.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move the call to vmtruncate to get rid of accessive blocks to the callers
in preparation of the new truncate sequence and rename the non-truncating
version to block_write_begin.

While we're at it also remove several unused arguments to block_write_begin.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This fixes this warning when building the kernel:
  CC      fs/udf/super.o
fs/udf/super.c: In function 'udf_load_sequence':
fs/udf/super.c:1582:22: warning: variable 'sbi' set but not used
Please have a look, when you have time and let me know.
Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Remove duplicated #include('s) in
  fs/udf/file.c
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

We don't name our generic fsync implementations very well currently.
The no-op implementation for in-memory filesystems currently is called
simple_sync_file which doesn't make too much sense to start with,
the the generic one for simple filesystems is called simple_fsync
which can lead to some confusion.

This patch renames the generic file fsync method to generic_file_fsync
to match the other generic_file_* routines it is supposed to be used
with, and the no-op implementation to noop_fsync to make it obvious
what to expect.  In addition add some documentation for both methods.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Do not use the fallback default_llseek() if the readdir operation of the
filesystem still uses the big kernel lock.

Since llseek() modifies
file->f_pos of the directory directly it may need locking to not confuse
readdir which usually uses file->f_pos directly as well

Since the special characteristics of the BKL (unlocked on schedule) are
not necessary in this case, the inode mutex can be used for locking as
provided by generic_file_llseek().  This is only possible since all
filesystems, except reiserfs, either use a directory as a flat file or
with disk address offsets.  Reiserfs on the other hand uses a 32bit hash
off the filename as the offset so generic_file_llseek() can get used as
well since the hash is always smaller than sb->s_maxbytes (= (512 << 32) -
blocksize).
Signed-off-by: NJan Blunck <jblunck@suse.de>
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: NAnders Larsen <al@alarsen.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Quota on UDF is non-functional at least since 2.6.16 (I'm too lazy to
do more archeology) because it does not provide .quota_write and .quota_read
functions and thus quotaon(8) just returns EINVAL. Since nobody complained
for all those years and quota support is not even in UDF standard just nuke
it.
Signed-off-by: NJan Kara <jack@suse.cz>

Follow the dquot_* style used elsewhere in dquot.c.

[Jan Kara: Fixed up missing conversion of ext2]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Only set the quota operation vectors if the filesystem actually supports
quota instead of doing it for all filesystems in alloc_super().

[Jan Kara: Export dquot_operations and vfs_quotactl_ops]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently the VFS calls into the quotactl interface for unmounting
filesystems.  This means filesystems with their own quota handling
can't easily distinguish between user-space originating quotaoff
and an unount.  Instead move the responsibily of the unmount handling
into the filesystem to be consistent with all other dquot handling.

Note that we do call dquot_disable a lot later now, e.g. after
a sync_filesystem.  But this is fine as the quota code does all its
writes via blockdev's mapping and that is synced even later.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Instead of having wrappers in the VFS namespace export the dquot_suspend
and dquot_resume helpers directly.  Also rename vfs_quota_disable to
dquot_disable while we're at it.

[Jan Kara: Moved dquot_suspend to quotaops.h and made it inline]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently do_remount_sb calls into the dquot code to tell it about going
from rw to ro and ro to rw.  Move this code into the filesystem to
not depend on the dquot code in the VFS - note ocfs2 already ignores
these calls and handles remount by itself.  This gets rid of overloading
the quotactl calls and allows to unify the VFS and XFS codepaths in
that area later.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Quota must being initialized if size or uid/git changes requested.
But initialization performed in two different places:
in case of i_size file system is responsible for dquot init
, but in case of uid/gid init will be called internally in
dquot_transfer().
This ambiguity makes code harder to understand.
Let's move this logic to one common helper function.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>

Convert udf_ioctl to an unlocked_ioctl and push the BKL down into it.

Signed-off-by: John Kacur <jkacur@redhat.com
Signed-off-by: NJan Kara <jack@suse.cz>

generic setattr not longer responsible for quota transfer.
use udf_setattr for all udf's inodes.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NJan Kara <jack@suse.cz>