Change all function used in filesystem discovery during mount to user
standard kernel return values - -errno on error, 0 on success instead
of 1 on failure and 0 on success. This allows us to pass error number
(not just failure / success) so we can abort device scanning earlier
in case of errors like EIO or ENOMEM . Also we will be able to return
EROFS in case writeable mount is requested but writing isn't supported.
Signed-off-by: NJan Kara <jack@suse.cz>

Somehow I failed to add the MODULE_ALIAS_FS for cifs, hostfs, hpfs,
squashfs, and udf despite what I thought were my careful checks :(

Add them now.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

s_extLength was assigned to but the value was never really used. So
just remove the field.
Signed-off-by: NJan Kara <jack@suse.cz>

struct udf_bitmap has array of buffer pointers attached to it. The code
unnecessarily used s_block_bitmap as a pointer to the array instead of
the standard trick of using 0 length array in the declaration. Change
that to make code more readable and actually shrink the structure by one
pointer.
Signed-off-by: NJan Kara <jack@suse.cz>

This patch implements extent caching in case of file reading.
While reading a file, currently, UDF reads metadata serially
which takes a lot of time depending on the number of extents present
in the file. Caching last accessd extent improves metadata read time.
Instead of reading file metadata from start, now we read from
the cached extent.

This patch considerably improves the time spent by CPU in kernel mode.
For example, while reading a 10.9 GB file using dd:
Time before applying patch:
11677022208 bytes (10.9GB) copied, 1529.748921 seconds, 7.3MB/s
real    25m 29.85s
user    0m 12.41s
sys     15m 34.75s

Time after applying patch:
11677022208 bytes (10.9GB) copied, 1469.338231 seconds, 7.6MB/s
real    24m 29.44s
user    0m 15.73s
sys     3m 27.61s

[JK: Fix bh refcounting issues, simplify initialization]
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAshish Sangwan <a.sangwan@samsung.com>
Signed-off-by: NBonggil Bak <bgbak@samsung.com>
Signed-off-by: NJan Kara <jack@suse.cz>

So far we just marked the buffer as dirty and left writing on flusher thread
but especially on opening that opens possible race window where we could write
other modified fs structures to disk before we mark filesystem as open. So sync
LVID buffer to disk after opening and closing fs.
Reported-by: NSteve Nickel <snickel58@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

This patch fixes a regression caused by commit bff943af "udf: Fix memory
leak when mounting" due to which it was triggering a kernel null point
dereference in case of interrupted mount OR when allocating memory to
sbi->s_partmaps failed in function udf_sb_alloc_partition_maps.
Reported-and-tested-by: NJames Hogan <james@albanarts.com>
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAshish Sangwan <a.sangwan@samsung.com>
Signed-off-by: NJan Kara <jack@suse.cz>

There's no reason to call rcu_barrier() on every
deactivate_locked_super().  We only need to make sure that all delayed rcu
free inodes are flushed before we destroy related cache.

Removing rcu_barrier() from deactivate_locked_super() affects some fast
paths.  E.g.  on my machine exit_group() of a last process in IPC
namespace takes 0.07538s.  rcu_barrier() takes 0.05188s of that time.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

In case we detect a problem and bail out, we fail to set "ret" to a
nonzero value, and udf_load_logicalvol will mistakenly report success.
Signed-off-by: NNikola Pajkovsky <npajkovs@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

If s_lvid_bh is not freed and set to NULL before re-scanning partition
with default block size, we might end up using wrong lvid in case
s_lvid_bh is not updated in udf_load_logicalvolint during rescan.
Signed-off-by: NAshish Sangwan <ashish.sangwan2@gmail.com>
Signed-off-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

When a partition table length is corrupted to be close to 1 << 32, the
check for its length may overflow on 32-bit systems and we will think
the length is valid. Later on the kernel can crash trying to read beyond
end of buffer. Fix the check to avoid possible overflow.

CC: stable@vger.kernel.org
Reported-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NJan Kara <jack@suse.cz>

When we are mounting filesystem, we can load one partition table before
finding out that we cannot complete processing of logical volume descriptor
and trying the reserve descriptor. Free the table properly before trying
the reserve descriptor.
Signed-off-by: NJan Kara <jack@suse.cz>

The UDF file-system does not need the 's_dirt' superblock flag because it does
not define the 'write_super()' method. This flag was set to 1 in few places and
set to 0 in '->sync_fs()' and was basically useless. Stop using it because it
is on its way out.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Add sanity checks when loading sparing table from disk to avoid accessing
unallocated memory or writing to it.
Signed-off-by: NJan Kara <jack@suse.cz>

Check provided length of partition table so that (possibly maliciously)
corrupted partition table cannot cause accessing data beyond current buffer.
Signed-off-by: NJan Kara <jack@suse.cz>

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

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

New field of struct super_block - ->s_max_links.  Maximal allowed
value of ->i_nlink or 0; in the latter case all checks still need
to be done in ->link/->mkdir/->rename instances.  Note that this
limit applies both to directoris and to non-directories.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Per call site OOM messages are unnecessary.
k.alloc and v.alloc failures use dump_stack().
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

When we hit EIO while writing LVID, the buffer uptodate bit is cleared.
This then results in an anoying warning from mark_buffer_dirty() when we
write the buffer again. So just set uptodate flag unconditionally.
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

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

note re mount options: fmask and dmask are explicitly truncated to 12bit,
UDF_INVALID_MODE just needs to be guaranteed to differ from any such value.
And umask is used only in &= with umode_t, so we ignore other bits anyway.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Use simple ->s_flags variable instead of u8 variable for each flag.
Signed-off-by: NJan Kara <jack@suse.cz>

It is not necessary to load mirror metadata FE when metadata FE is OK.  So try
to read it only the first time udf_get_pblock_meta25() fails to map the block
from metadata FE.
Signed-off-by: NAshish Sangwan <ashishsangwan2@gmail.com>
Signed-off-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Just whitespace and argument alignment.
Introduce some checkpatch warnings that deserve to be ignored.
Reviewed-by: NNamJae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Use %pV and remove a static buffer to save some text space and fix possible
issues when several processes call error reporting function in parallel. Also
change error level from KERN_CRIT to KERN_ERR.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Use the current logging styles.

Convert a few printks that should have been udf_warn and udf_err.
Coalesce formats.  Add #define pr_fmt.
Move an #include "udfdecls.h" above other includes in udftime.c
so pr_fmt works correctly.  Strip prefixes from conversions as appropriate.
Reorder logging definitions in udfdecl.h
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Rename udf_warning to udf_warn for consistency with normal logging
uses of pr_warn.

Rename function udf_warning to _udf_warn.
Remove __func__ from uses and move __func__ to a new udf_warn
macro that calls _udf_warn.
Add \n's to uses of udf_warn, remove \n from _udf_warn.
Coalesce formats.
Reviewed-by: NNamJae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Rename udf_error to udf_err for consistency with normal logging
uses of pr_err.

Rename function udf_err to _udf_err.
Remove __func__ from uses and move __func__ to a new udf_err
macro that calls _udf_err.
Some of the udf_error uses had \n terminations, some did not so
standardize \n's to udf_err uses, remove \n from _udf_err function.
Coalesce udf_err formats.
One message prefixed with udf_read_super is now prefixed with
udf_fill_super.
Reviewed-by: NNamJae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

If there is a problem with a scratched disc or loader, it's valuable to know
which error occurred.

Convert some debug messages to udf_error, neaten those messages too.
Add the calculated tag checksum and the read checksum to error message.
Make udf_error a public function and move the logging prototypes together.
Original-patch-by: NNamJae Jeon <linkinjeon@gmail.com>
Reviewed-by: NNamJae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJan Kara <jack@suse.cz>

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>

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>

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>

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>