It is not very good to do IO in udf_clear_inode. First, VFS does not really
expect inode to become dirty there and thus we have to write it ourselves,
second, memory reclaim gets blocked waiting for IO when it does not really
expect it, third, the IO pattern (e.g. on umount) resulting from writes in
udf_clear_inode is bad and it slows down writing a lot.

The reason why UDF needed to do IO in udf_clear_inode is that UDF standard
mandates extent length to exactly match inode size. But when we allocate
extents to a file or directory, we don't really know what exactly the final
file size will be and thus temporarily set it to block boundary and later
truncate it to exact length in udf_clear_inode. Now, this is changed to
truncate to final file size in udf_release_file for regular files. For
directories and symlinks, we do the truncation at the moment when learn
what the final file size will be.
Signed-off-by: Jan Kara <jack@suse.cz>

Some disks do not contain VAT inode in the last recorded block as required
by the standard but a few blocks earlier (or the number of recorded blocks
is wrong). So look for the VAT inode a bit before the end of the media.
Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Jan Kara <jack@suse.cz>

When we close a file, we remove preallocated blocks from it. But this
truncation was not protected by i_mutex and thus it could have raced with a
write through a different fd and cause crashes or even filesystem corruption.
Signed-off-by: Jan Kara <jack@suse.cz>

So far we preallocated blocks also for directories but that brings a
problem, when to get rid of preallocated blocks we don't need. So far
we removed them in udf_clear_inode() which has a disadvantage that
1) blocks are unavailable long after writing to a directory finished
   and thus one can get out of space unnecessarily early
2) releasing blocks from udf_clear_inode is problematic because VFS
   does not expect us to redirty inode there and it also slows down
   memory reclaim.

So preallocate blocks only for regular files where we can drop preallocation
in udf_release_file.
Signed-off-by: Jan Kara <jack@suse.cz>

Recomputation of the pointer was wrong (it should have been just increment).
Luckily, we never use the computed value. Remove it.
Signed-off-by: Jan Kara <jack@suse.cz>

Remove code that gets never used.
Signed-off-by: Jan Kara <jack@suse.cz>

VAT inode is located in the last block recorded block of the medium. When the
drive errorneously reports number of recorded blocks, we failed to load the VAT
inode and thus mount the medium. This patch makes kernel try to read VAT inode
from the last block of the device if it is different from the last recorded
block.
Signed-off-by: Jan Kara <jack@suse.cz>

first_block and goal are unsigned. When negative they are wrapped and caught by
the other test.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Some drives report 0 as the number of written blocks when there are some blocks
recorded. Use device size in such case so that we can automagically mount such
media.
Signed-off-by: Jan Kara <jack@suse.cz>

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

[xfs, btrfs, capifs, shmem don't need BKL, exempt]
Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Move BKL into ->put_super from the only caller.  A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment.  Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.

[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

We update information in logical volume integrity descriptor after each
allocation (as LVID contains free space, number of directories and files on
disk etc.). If the filesystem is on some phase change media, this leads to its
quick degradation as such media is able to handle only 10000 overwrites or so.
We solve the problem by writing new information into LVID only on umount,
remount-ro and sync. This solves the problem at the price of longer media
inconsistency (previously media became consistent after pdflush flushed dirty
LVID buffer) but that should be acceptable.

Report by and patch written in cooperation with
Rich Coe <Richard.Coe@med.ge.com>.
Signed-off-by: Jan Kara <jack@suse.cz>

Anchor block can be located at several places on the medium. Two of the
locations are relative to media end which is problematic to detect. Also
some drives report some block as last but are not able to read it or any
block nearby before it. So let's first try block 256 and if it is all fine,
don't look at other possible locations of anchor blocks to avoid IO errors.
This change required a larger reorganization of code but the new code is
hopefully more readable and definitely shorter.
Signed-off-by: Jan Kara <jack@suse.cz>

Make udf_check_valid() return 1 if the validity check passed and 0 otherwise.
So far it was the other way around which was a bit confusing. Also make
udf_vrs() return loff_t which is really the type it should return (not int).
Signed-off-by: Jan Kara <jack@suse.cz>

This patch makes the UDF FS driver use the hardware sector size as the
default logical block size, which is required by the UDF specifications.
While the previous default of 2048 bytes was correct for optical disks,
it was not for hard disks or USB storage devices, and made it impossible
to use such a device with the default mount options.  (The Linux mkudffs
tool uses a default block size of 2048 bytes even on devices with
smaller hardware sectors, so this bug is unlikely to be noticed unless
UDF-formatted USB storage devices are exchanged with other OSs.)

To avoid regressions for people who use loopback optical disk images or
who used the (sometimes wrong) defaults of mkudffs, we also try with
a block size of 2048 bytes if no anchor was found with the hardware
sector size.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jan Kara <jack@suse.cz>

The novrs mount option was broken due to a missing break.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jan Kara <jack@suse.cz>

Functions udf_CS0toNLS() and udf_NLStoCS0() didn't count with the fact that
NLS can return negative length when invalid character is given to it for
conversion. Thus interesting things could happen (such as overwriting random
memory with the rest of filename). Add appropriate checks.
Signed-off-by: Jan Kara <jack@suse.cz>

This patch makes udf return f_fsid info for statfs(2).
Signed-off-by: Coly Li <coly.li@suse.de>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Jan Kara <jack@suse.cz>

On x86 (and several other archs) mode_t is defined as "unsigned short"
and comparing unsigned shorts to negative ints is broken (because short
is promoted to int and then compared). Fix it.
Reported-and-tested-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Fix sparse warnings:

  fs/udf/balloc.c:843:3: warning: returning void-valued expression
  fs/udf/balloc.c:847:3: warning: returning void-valued expression
  fs/udf/balloc.c:851:3: warning: returning void-valued expression
  fs/udf/balloc.c:855:3: warning: returning void-valued expression
Reported-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Jan Kara <jack@suse.cz>

unsigned last[i] cannot be less than 0
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

"dmode" allows overriding permissions of directories and
"mode" allows overriding permissions of files.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>

Allocate strings with kmalloc.

Checkstack output:
Before: udf_get_filename:          600
After:  udf_get_filename:          136
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>

Allocate strings with kmalloc.

Checkstack output:
Before: udf_process_sequence:      712
After:  udf_process_sequence:      200
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Jan Kara <jack@suse.cz>

Use lowercase names of quota functions instead of old uppercase ones.
Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

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>

Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>

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

Switch all users of d_alloc_anon to d_obtain_alias.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.

This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

UDF currently doesn't set a llseek method for regular files, which
means it will fall back to default_llseek.  This means no one can seek
beyond 2 Gigabytes on udf, and that there's not protection vs
the i_size updates from writers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

I case we failed to allocate memory for inode when creating it, we did not
properly free block already allocated for this inode. Move memory allocation
before the block allocation which fixes this issue (thanks for the idea go to
Ingo Oeser <ioe-lkml@rameria.de>). Also remove a few superfluous
initializations already done in udf_alloc_inode().
Reviewed-by: Ingo Oeser <ioe-lkml@rameria.de>
Signed-off-by: Jan Kara <jack@suse.cz>

A memory allocation inside alloc_mutex must not recurse back into the
filesystem itself because that leads to lock inversion between iprune_mutex and
alloc_mutex (and thus to deadlocks - see traces below). alloc_mutex is actually
needed only to update allocation statistics in the superblock so we can drop it
before we start allocating memory for the inode.

tar           D ffff81015b9c8c90     0  6614   6612
 ffff8100d5a21a20 0000000000000086 0000000000000000 00000000ffff0000
 ffff81015b9c8c90 ffff81015b8f0cd0 ffff81015b9c8ee0 0000000000000000
 0000000000000003 0000000000000000 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff803c1d8a>] __mutex_lock_slowpath+0x64/0x9b
 [<ffffffff803c1bef>] mutex_lock+0xa/0xb
 [<ffffffff8027f8c2>] shrink_icache_memory+0x38/0x200
 [<ffffffff80257742>] shrink_slab+0xe3/0x15b
 [<ffffffff802579db>] try_to_free_pages+0x221/0x30d
 [<ffffffff8025657e>] isolate_pages_global+0x0/0x31
 [<ffffffff8025324b>] __alloc_pages_internal+0x252/0x3ab
 [<ffffffff8026b08b>] cache_alloc_refill+0x22e/0x47b
 [<ffffffff8026ae37>] kmem_cache_alloc+0x3b/0x61
 [<ffffffff8026b15b>] cache_alloc_refill+0x2fe/0x47b
 [<ffffffff8026b34e>] __kmalloc+0x76/0x9c
 [<ffffffffa00751f2>] :udf:udf_new_inode+0x202/0x2e2
 [<ffffffffa007ae5e>] :udf:udf_create+0x2f/0x16d
 [<ffffffffa0078f27>] :udf:udf_lookup+0xa6/0xad
...
kswapd0       D ffff81015b9d9270     0   125      2
 ffff81015b903c28 0000000000000046 ffffffff8028cbb0 00000000fffffffb
 ffff81015b9d9270 ffff81015b8f0cd0 ffff81015b9d94c0 000000000271b490
 ffffe2000271b458 ffffe2000271b420 ffffe20002728dc8 ffffe20002728d90
Call Trace:
 [<ffffffff8028cbb0>] __set_page_dirty+0xeb/0xf5
 [<ffffffff8025403a>] get_dirty_limits+0x1d/0x22f
 [<ffffffff803c1d8a>] __mutex_lock_slowpath+0x64/0x9b
 [<ffffffff803c1bef>] mutex_lock+0xa/0xb
 [<ffffffffa0073f58>] :udf:udf_bitmap_free_blocks+0x47/0x1eb
 [<ffffffffa007df31>] :udf:udf_discard_prealloc+0xc6/0x172
 [<ffffffffa007875a>] :udf:udf_clear_inode+0x1e/0x48
 [<ffffffff8027f121>] clear_inode+0x6d/0xc4
 [<ffffffff8027f7f2>] dispose_list+0x56/0xee
 [<ffffffff8027fa5a>] shrink_icache_memory+0x1d0/0x200
 [<ffffffff80257742>] shrink_slab+0xe3/0x15b
 [<ffffffff80257e93>] kswapd+0x346/0x447
...
Reported-by: Tibor Tajti <tibor.tajti@gmail.com>
Reviewed-by: Ingo Oeser <ioe-lkml@rameria.de>
Signed-off-by: Jan Kara <jack@suse.cz>