Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page.  As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently.  At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate.  Reclaim will check
for this flag before installing shadow pages.
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: NRik van Riel <riel@redhat.com>
Reviewed-by: NMinchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Metin Doslu <metin@citusdata.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ozgun Erdogan <ozgun@citusdata.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

UDF has two types of files - files with data stored in inode (ICB in
UDF terminology) and files with data stored in external data blocks. We
convert file from in-inode format to external format in
udf_file_aio_write() when we find out data won't fit into inode any
longer. However the following race between two O_APPEND writes can happen:

CPU1					CPU2
udf_file_aio_write()			udf_file_aio_write()
  down_write(&iinfo->i_data_sem);
  checks that i_size + count1 fits within inode
    => no need to convert
  up_write(&iinfo->i_data_sem);
					  down_write(&iinfo->i_data_sem);
					  checks that i_size + count2 fits
					    within inode => no need to convert
					  up_write(&iinfo->i_data_sem);
  generic_file_aio_write()
    - extends file by count1 bytes
					  generic_file_aio_write()
					    - extends file by count2 bytes

Clearly if count1 + count2 doesn't fit into the inode, we overwrite
kernel buffers beyond inode, possibly corrupting the filesystem as well.

Fix the problem by acquiring i_mutex before checking whether write fits
into the inode and using __generic_file_aio_write() afterwards which
puts check and write into one critical section.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NJan Kara <jack@suse.cz>

truncate_pagecache() doesn't care about old size since commit
cedabed4 ("vfs: Fix vmtruncate() regression").  Let's drop it.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Faster kernel compiles by way of fewer unnecessary includes.

[akpm@linux-foundation.org: fix fallout]
[akpm@linux-foundation.org: fix build]
Signed-off-by: NKent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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>

The variable last_block is not needed.
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>

Incrementing lenExtents even while writing to a hole is bad
for performance as calls to udf_discard_prealloc and
udf_truncate_tail_extent would not return from start if
isize != lenExtents
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>

Need to brelse the buffer_head stored in cur_epos and next_epos.
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>

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

Add support for the O_DIRECT flag.  There are two cases to deal with:

1. Small files stored in the ICB (inode control block?): just return 0
from the new udf_adinicb_direct_IO() handler to fall back to buffered
I/O.

2. Larger files, not stored in the ICB: nothing special here.  Just call
blockdev_direct_IO() from our new udf_direct_IO() handler and tidy up
any blocks instantiated outside i_size on error.  This is pretty
standard.  Factor error handling code out of udf_write_begin() into new
function udf_write_failed() so it can also be called by udf_direct_IO().

Also change the whitespace in udf_aops to make it a bit neater.
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NJan Kara <jack@suse.cz>

Use mpage_writepages() instead of multiple calls to udf_writepage()
to make performance higher.

*Write Speed with writepage() =
 RecSize     ReadSpeed    WriteSpeed  RanReadSpeed RanWriteSpeed
10485760    0.00MB/sec    8.56MB/sec    0.00MB/sec    8.20MB/sec
 1048576    0.00MB/sec    8.57MB/sec    0.00MB/sec    6.42MB/sec
  524288    0.00MB/sec    8.59MB/sec    0.00MB/sec    5.24MB/sec
  262144    0.00MB/sec    8.59MB/sec    0.00MB/sec    4.17MB/sec
  131072    0.00MB/sec    8.53MB/sec    0.00MB/sec    3.32MB/sec
   65536    0.00MB/sec    8.49MB/sec    0.00MB/sec    2.31MB/sec

*Write Speed with writepages()
RecSize     ReadSpeed    WriteSpeed  RanReadSpeed RanWriteSpeed
10485760    0.00MB/sec    9.88MB/sec    0.00MB/sec    9.60MB/sec
 1048576    0.00MB/sec    9.95MB/sec    0.00MB/sec    7.52MB/sec
  524288    0.00MB/sec    9.98MB/sec    0.00MB/sec    6.16MB/sec
  262144    0.00MB/sec    9.90MB/sec    0.00MB/sec    4.98MB/sec
  131072    0.00MB/sec    9.89MB/sec    0.00MB/sec    3.78MB/sec
   65536    0.00MB/sec    9.81MB/sec    0.00MB/sec    2.50MB/sec

There is about 1.4MB/sec speed improvement over 8.5MB/sec,
which comes out around 16% improvement.
Signed-off-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NAshish Sangwan <ashish.sangwan2@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

If the new size is larger than the old size and the old file data was
stored in the ICB (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) and the
new size still fits in the ICB, skip the call to udf_extend_file() as it
does not handle this i_alloc_type value (it calls BUG()).
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NJan Kara <jack@suse.cz>

The variable "offset" is not needed. Remove it.
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>

After we moved inode_sync_wait() from end_writeback() it doesn't make sense
to call the function end_writeback() anymore. Rename it to clear_inode()
which well says what the function really does - set I_CLEAR flag.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>

ECMA 1.67 requires setting logicalBlocksRecorded to zero if the file
has no extents. This should be checked in udf_update_inode().
udf_fill_inode() will then take care of itself.
Signed-off-by: NSteven P. Nickel <snickel@focusinfo.com>
Signed-off-by: NJan Kara <jack@suse.cz>

In accordance with ECMA 1.67 Part 4, 14.9.15, the checkpoint field
should be initialized to 1 at creation. (Zero is *not* a valid value.)
Signed-off-by: NSteven P. Nickel <snickel@focusinfo.com>
Signed-off-by: NJan Kara <jack@suse.cz>

During BKL removal in 2.6.38, conversion of files from in-ICB format to normal
format got broken. We call ->writepage with i_data_sem held but udf_get_block()
also acquires i_data_sem thus creating A-A deadlock.

We fix the problem by dropping i_data_sem before calling ->writepage() which is
safe since i_mutex still protects us against any changes in the file. Also fix
pagelock - i_data_sem lock inversion in udf_expand_file_adinicb() by dropping
i_data_sem before calling find_or_create_page().

CC: stable@kernel.org
Reported-by: NMatthias Matiak <netzpython@mail-on.us>
Tested-by: NMatthias Matiak <netzpython@mail-on.us>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

inode_getblk() always returned NULL and passed results in its parameters.
Make the function return something useful - found block number.
Signed-off-by: NJan Kara <jack@suse.cz>

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>

Replace remaining direct i_nlink updates with a new set_nlink()
updater function.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Tested-by: NToshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

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 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>

Use mpage_readpages() instead of multiple calls to udf_readpage() to reduce the
CPU utilization and make performance higher.
Signed-off-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

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>

Use new truncation sequence in UDF and fix up error handling in the
code.
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>

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>

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_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>

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>

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>

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>

We needlessly read inode in udf_update_inode just before zeroing out the
contents of the buffer. Fix it.
Signed-off-by: NJan Kara <jack@suse.cz>

Writing of inode holding unallocated space info was broken because we first
cleared the buffer and after that checked whether it contains a tag meaning the
block holds unallocated space information.  Fix the problem by checking
appropriate in memory flag instead.

Also cleanup the function a bit along the way - most importantly lock buffer
when modifying its contents, check for buffer_write_io_error instead of
!buffer_uptodate, etc..
Signed-off-by: NJan Kara <jack@suse.cz>

This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Get rid of the initialize dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_initialize helper to __dquot_initialize
and vfs_dq_init to dquot_initialize to have a consistent namespace.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently various places in the VFS call vfs_dq_init directly.  This means
we tie the quota code into the VFS.  Get rid of that and make the
filesystem responsible for the initialization.   For most metadata operations
this is a straight forward move into the methods, but for truncate and
open it's a bit more complicated.

For truncate we currently only call vfs_dq_init for the sys_truncate case
because open already takes care of it for ftruncate and open(O_TRUNC) - the
new code causes an additional vfs_dq_init for those which is harmless.

For open the initialization is moved from do_filp_open into the open method,
which means it happens slightly earlier now, and only for regular files.
The latter is fine because we don't need to initialize it for operations
on special files, and we already do it as part of the namespace operations
for directories.

Add a dquot_file_open helper that filesystems that support generic quotas
can use to fill in ->open.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Get rid of the drop dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_drop helper to __dquot_drop
and vfs_dq_drop to dquot_drop to have a consistent namespace.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently clear_inode calls vfs_dq_drop directly.  This means
we tie the quota code into the VFS.  Get rid of that and make the
filesystem responsible for the drop inside the ->clear_inode
superblock operation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>