Current implementation of udf_translate_to_linux function does not
support multi-bytes characters at all: it counts bytes while calculating
extension length, when inserting CRC inside the name it doesn't
take into account inter-character boundaries and can break into
the middle of the character.

The most efficient way to properly support multi-bytes characters is
merging of translation operations directly into conversion function.
This can help to avoid extra passes along the string or parsing
the multi-bytes character back into unicode to find out it's length.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Although 'struct ustr' tries to structurize the data by combining
the string and its length, it doesn't actually make much benefit,
since it saves only one parameter, but introduces an extra copying
of the whole buffer, serving as an intermediate storage. It looks
quite inefficient and not actually needed.

This commit gets rid of the struct ustr by changing the parameters
of some functions appropriately.

Also, it removes using 'dstring' type, since it doesn't make much
sense too.

Just using the occasion, add a 'const' qualifier to udf_get_filename
to make consistent parameters sets.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Code in udf_find_entry() and udf_readdir() used the same buffer for
storing filename that was split among blocks and for the resulting
filename in utf8. This worked because udf_get_filename() first
internally copied the name into a different buffer and only then
performed a conversion into the destination buffer. However we want to
get rid of intermediate buffers so use separate buffer for converted
name and name split between blocks so that we don't have the same source
and destination buffer when converting split names.

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

Actual name length restriction is 254 bytes, this is used in 'ustr'
structure, and this is what fits into UDF File Ident structures.
And in most cases the constant is used as UDF_NAME_LEN-2.
So, it's better to just modify the constant to make it closer
to reality.

Also, in some cases it's useful to have a separate constant for
the maximum length of file name field in CS0 encoding in UDF File
Ident structures.

Also, remove the unused UDF_PATH_LEN constant.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>

There is no much sense to have separate functions for UTF8 and
NLS conversions, since UTF8 encoding is actually the special case
of NLS.

However, although UTF8 is also supported by general NLS framework,
it would be good to have separate UTF8 character conversion functions
(char2uni and uni2char) locally in UDF code, so that they could be
used even if NLS support is not enabled in the kernel configuration.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Make the desired output length a parameter rather than have it
hard-coded to UDF_NAME_LEN. Although all call sites still have
this length the same, this parameterization will make the function
more universal and also consistent with udf_get_filename.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Pull final vfs updates from Al Viro:

 - The ->i_mutex wrappers (with small prereq in lustre)

 - a fix for too early freeing of symlink bodies on shmem (they need to
   be RCU-delayed) (-stable fodder)

 - followup to dedupe stuff merged this cycle

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: abort dedupe loop if fatal signals are pending
  make sure that freeing shmem fast symlinks is RCU-delayed
  wrappers for ->i_mutex access
  lustre: remove unused declaration

There are many locations that do

  if (memory_was_allocated_by_vmalloc)
    vfree(ptr);
  else
    kfree(ptr);

but kvfree() can handle both kmalloc()ed memory and vmalloc()ed memory
using is_vmalloc_addr().  Unless callers have special reasons, we can
replace this branch with kvfree().  Please check and reply if you found
problems.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Acked-by: David Rientjes <rientjes@google.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Boris Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

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

Pull UDF fixes and quota cleanups from Jan Kara:
 "Several UDF fixes and some minor quota cleanups"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Check output buffer length when converting name to CS0
  udf: Prevent buffer overrun with multi-byte characters
  quota: constify qtree_fmt_operations structures
  udf: avoid uninitialized variable use
  udf: Fix lost indirect extent block
  udf: Factor out code for creating indirect extent
  udf: limit the maximum number of indirect extents in a row
  udf: limit the maximum number of TD redirections
  fs: make quota/dquot.c explicitly non-modular
  fs: make quota/netlink.c explicitly non-modular