Commit Graph

1111 Commits

Author SHA1 Message Date
Coly Li
7c78605929 mballoc: add comments to ext4_mb_mark_free_simple()
This patch adds comments to ext4_mb_mark_free_simple to make it more
understandable.

Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
2011-02-24 13:24:25 -05:00
Coly Li
235772da3e ext4: remove unncessary call mb_find_buddy() in debugging code
In __mb_check_buddy(), look at the code below:
  591         fstart = -1;
  592         buddy = mb_find_buddy(e4b, 0, &max);
  593         for (i = 0; i < max; i++) {
  594                 if (!mb_test_bit(i, buddy)) {
  595                         MB_CHECK_ASSERT(i >= e4b->bd_info->bb_first_free);
  596                         if (fstart == -1) {
  597                                 fragments++;
  598                                 fstart = i;
  599                         }
  600                         continue;
  601                 }
  602                 fstart = -1;
  603                 /* check used bits only */
  604                 for (j = 0; j < e4b->bd_blkbits + 1; j++) {
  605                         buddy2 = mb_find_buddy(e4b, j, &max2);
  606                         k = i >> j;
  607                         MB_CHECK_ASSERT(k < max2);
  608                         MB_CHECK_ASSERT(mb_test_bit(k, buddy2));
  609                 }
  610         }
  611         MB_CHECK_ASSERT(!EXT4_MB_GRP_NEED_INIT(e4b->bd_info));
  612         MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);
  613
  614         grp = ext4_get_group_info(sb, e4b->bd_group);
  615         buddy = mb_find_buddy(e4b, 0, &max);

On line 592, buddy is fetched by mb_find_buddy() with order 0, between
line 593 to line 615, buddy is not changed, therefore there is
no need to fetch buddy again from mb_find_buddy() with order 0 again.

We can safely remove the second mb_find_buddy() on line 615.

Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
2011-02-24 13:24:18 -05:00
Coly Li
84b775a354 ext4: code cleanup in mb_find_buddy()
Current code calculate max no matter whether order is zero, it's
unnecessary. This cleanup patch sets max to "1 << (e4b->bd_blkbits
+ 3)" only when order == 0.

Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
2011-02-24 12:51:59 -05:00
Eric Sandeen
ea66333694 ext4: enable acls and user_xattr by default
There's no good reason to require the extra step of providing
a mount option for acl or user_xattr once the feature is configured
on; no other filesystem that I know of requires this.

Userspace patches have set these options in default mount options,
and this patch makes them default in the kernel.  At some point
we can start to deprecate the options, perhaps.

For now I've removed default mount option checks in show_options()
to be explicit about what's set, since it's changing the default,
but I'm open to alternatives if desired.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-23 17:51:51 -05:00
Lukas Czerner
5c2ed62fd4 ext4: Adjust minlen with discard_granularity in the FITRIM ioctl
Discard granularity tells us the minimum size of extent that can be
discarded by the device.  If the user supplies a minimum extent that
should be discarded (range.minlen) which is smaller than the discard
granularity, increase minlen to the discard granularity, since there's
no point submitting trim requests that the device will reject anyway.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-23 17:49:51 -05:00
Lukas Czerner
4143179218 ext4: check if device support discard in FITRIM ioctl
For a device that does not support discard, the FITRIM ioctl returns
-EOPNOTSUPP when blkdev_issue_discard() returns this error code, which
is how the user is informed that the device does not support discard.

If there are no suitable free extents to be trimmed, then FITRIM will
return success even though the device does not support discard, which
could confuse the user.  So check explicitly if the device supports
discard and return an error code at the beginning of the FITRIM ioctl
processing.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-23 12:42:32 -05:00
Lukas Czerner
0b75a84012 ext4: mark file-local functions and variables as static
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-23 12:22:49 -05:00
Alexander V. Lukyanov
5dbd571d87 ext4: allow inode_readahead_blks=0 (linux-2.6.37)
I cannot disable inode-read-ahead feature of ext4 (on 2.6.37):

# echo 0 > /sys/fs/ext4/sda2/inode_readahead_blks 
bash: echo: write error: Invalid argument

On a server with lots of small files and random access this read-ahead makes
performance worse, and I'd like to disable it. I work around this problem
by using value of 1, but it still reads an extra block.

This patch fixes the problem by checking for zero explicitly.

Signed-off-by: Alexander V. Lukyanov <lav@netis.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-21 21:33:21 -05:00
Peter Huewe
7dc576158d ext4: Fix sparse warning: Using plain integer as NULL pointer
This patch fixes the warning "Using plain integer as NULL pointer",
generated by sparse, by replacing the offending 0s with NULL.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-21 21:01:42 -05:00
Theodore Ts'o
da488945f4 ext4: fix compile warnings with EXT4FS_DEBUG enabled
Compile 2.6.38-rc1 with turning EXT4FS_DEBUG on,
we get following compile warnings. This patch fixes them.

  CC      fs/ext4/hash.o
  CC      fs/ext4/resize.o
fs/ext4/resize.c: In function 'setup_new_group_blocks':
fs/ext4/resize.c:233:2: warning: format '%#04llx' expects type 'long long
unsigned int', but argument 3 has type 'long unsigned int'
fs/ext4/resize.c:251:2: warning: format '%#04llx' expects type 'long long
unsigned int', but argument 3 has type 'long unsigned int'
  CC      fs/ext4/extents.o
  CC      fs/ext4/ext4_jbd2.o
  CC      fs/ext4/migrate.o

Reported-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-21 20:39:58 -05:00
Eric Sandeen
e9e3bcecf4 ext4: serialize unaligned asynchronous DIO
ext4 has a data corruption case when doing non-block-aligned
asynchronous direct IO into a sparse file, as demonstrated
by xfstest 240.

The root cause is that while ext4 preallocates space in the
hole, mappings of that space still look "new" and 
dio_zero_block() will zero out the unwritten portions.  When
more than one AIO thread is going, they both find this "new"
block and race to zero out their portion; this is uncoordinated
and causes data corruption.

Dave Chinner fixed this for xfs by simply serializing all
unaligned asynchronous direct IO.  I've done the same here.
The difference is that we only wait on conversions, not all IO.
This is a very big hammer, and I'm not very pleased with
stuffing this into ext4_file_write().  But since ext4 is
DIO_LOCKING, we need to serialize it at this high level.

I tried to move this into ext4_ext_direct_IO, but by then
we have the i_mutex already, and we will wait on the
work queue to do conversions - which must also take the
i_mutex.  So that won't work.

This was originally exposed by qemu-kvm installing to
a raw disk image with a normal sector-63 alignment.  I've
tested a backport of this patch with qemu, and it does
avoid the corruption.  It is also quite a lot slower
(14 min for package installs, vs. 8 min for well-aligned)
but I'll take slow correctness over fast corruption any day.

Mingming suggested that we can track outstanding
conversions, and wait on those so that non-sparse
files won't be affected, and I've implemented that here;
unaligned AIO to nonsparse files won't take a perf hit.

[tytso@mit.edu: Keep the mutex as a hashed array instead
 of bloating the ext4 inode]

[tytso@mit.edu: Fix up namespace issues so that global
 variables are protected with an "ext4_" prefix.]

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-12 08:17:34 -05:00
Eric Sandeen
2892c15ddd ext4: make grpinfo slab cache names static
In 2.6.37 I was running into oopses with repeated module
loads & unloads.  I tracked this down to:

fb1813f4 ext4: use dedicated slab caches for group_info structures

(this was in addition to the features advert unload problem)

The kstrdup & subsequent kfree of the cache name was causing
a double free.  In slub, at least, if I read it right it allocates
& frees the name itself, slab seems to do something different...
so in slub I think we were leaking -our- cachep->name, and double
freeing the one allocated by slub.

After getting lost in slab/slub/slob a bit, I just looked at other
sized-caches that get allocated.  jbd2, biovec, sgpool all do it
more or less the way jbd2 does.  Below patch follows the jbd2
method of dynamically allocating a cache at mount time from
a list of static names.

(This might also possibly fix a race creating the caches with
parallel mounts running).

[Folded in a fix from Dan Carpenter which fixed an off-by-one error in
the original patch]

Cc: stable@kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-12 08:12:18 -05:00
Curt Wohlgemuth
d50bdd5aa5 ext4: Fix data corruption with multi-block writepages support
This fixes a corruption problem with the multi-block
writepages submittal change for ext4, from commit
bd2d0210cf ("ext4: use bio
layer instead of buffer layer in mpage_da_submit_io").

(Note that this corruption is not present in 2.6.37 on
ext4, because the corruption was detected after the
feature was merged in 2.6.37-rc1, and so it was turned
off by adding a non-default mount option,
mblk_io_submit.  With this commit, which hopefully
fixes the last of the bugs with this feature, we'll be
able to turn on this performance feature by default in
2.6.38, and remove the mblk_io_submit option.)

The ext4 code path to bundle multiple pages for
writeback in ext4_bio_write_page() had a bug: we should
be clearing buffer head dirty flags *before* we submit
the bio, not in the completion routine.

The patch below was tested on 2.6.37 under KVM with the
postgresql script which was submitted by Jon Nelson as
documented in commit 1449032be1.

Without the patch, I'd hit the corruption problem about
50-70% of the time.  With the patch, I executed the
script > 100 times with no corruption seen.

I also fixed a bug to make sure ext4_end_bio() doesn't
dereference the bio after the bio_put() call.

Reported-by: Jon Nelson <jnelson@jamponi.net>
Reported-by: Matthias Bayer <jackdachef@gmail.com>
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2011-02-07 12:46:14 -05:00
Theodore Ts'o
dd68314ccf ext4: fix up ext4 error handling
Make sure we the correct cleanup happens if we die while trying to
load the ext4 file system.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-03 14:33:49 -05:00
Lukas Czerner
8f021222c1 ext4: unregister features interface on module unload
Ext4 features interface was not properly unregistered which led to
problems while unloading/reloading ext4 module. This commit fixes that by
adding proper kobject unregistration code into ext4_exit_fs() as well as
fail-path of ext4_init_fs()

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2011-02-03 14:33:33 -05:00
Eric Sandeen
8f1f745331 ext4: fix panic on module unload when stopping lazyinit thread
https://bugzilla.kernel.org/show_bug.cgi?id=27652

If the lazyinit thread is running, the teardown function
ext4_destroy_lazyinit_thread() has problems:

        ext4_clear_request_list();
        while (ext4_li_info->li_task) {
                wake_up(&ext4_li_info->li_wait_daemon);
                wait_event(ext4_li_info->li_wait_task,
                           ext4_li_info->li_task == NULL);
        }

Clearing the request list will cause the thread to exit and free
ext4_li_info, so then we're waiting on something which is getting
freed.

Fix this up by making the thread respond to kthread_stop, and exit,
without the need to wait for that exit in some other homegrown way.

Cc: stable@kernel.org
Reported-and-Tested-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-03 14:33:15 -05:00
Linus Torvalds
4843456c5c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  quota: Fix deadlock during path resolution
2011-01-21 07:33:37 -08:00
Christoph Hellwig
2fe17c1075 fallocate should be a file operation
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 02:25:31 -05:00
Christoph Hellwig
64c23e8687 make the feature checks in ->fallocate future proof
Instead of various home grown checks that might need updates for new
flags just check for any bit outside the mask of the features supported
by the filesystem.  This makes the check future proof for any newly
added flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 02:25:30 -05:00
Linus Torvalds
275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Linus Torvalds
b2034d474b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
  fs: add documentation on fallocate hole punching
  Gfs2: fail if we try to use hole punch
  Btrfs: fail if we try to use hole punch
  Ext4: fail if we try to use hole punch
  Ocfs2: handle hole punching via fallocate properly
  XFS: handle hole punching via fallocate properly
  fs: add hole punching to fallocate
  vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
  fix signedness mess in rw_verify_area() on 64bit architectures
  fs: fix kernel-doc for dcache::prepend_path
  fs: fix kernel-doc for dcache::d_validate
  sanitize ecryptfs ->mount()
  switch afs
  move internal-only parts of ncpfs headers to fs/ncpfs
  switch ncpfs
  switch 9p
  pass default dentry_operations to mount_pseudo()
  switch hostfs
  switch affs
  switch configfs
  ...
2011-01-13 10:27:28 -08:00
Linus Torvalds
008d23e485 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  Documentation/trace/events.txt: Remove obsolete sched_signal_send.
  writeback: fix global_dirty_limits comment runtime -> real-time
  ppc: fix comment typo singal -> signal
  drivers: fix comment typo diable -> disable.
  m68k: fix comment typo diable -> disable.
  wireless: comment typo fix diable -> disable.
  media: comment typo fix diable -> disable.
  remove doc for obsolete dynamic-printk kernel-parameter
  remove extraneous 'is' from Documentation/iostats.txt
  Fix spelling milisec -> ms in snd_ps3 module parameter description
  Fix spelling mistakes in comments
  Revert conflicting V4L changes
  i7core_edac: fix typos in comments
  mm/rmap.c: fix comment
  sound, ca0106: Fix assignment to 'channel'.
  hrtimer: fix a typo in comment
  init/Kconfig: fix typo
  anon_inodes: fix wrong function name in comment
  fix comment typos concerning "consistent"
  poll: fix a typo in comment
  ...

Fix up trivial conflicts in:
 - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c)
 - fs/ext4/ext4.h

Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-13 10:05:56 -08:00
Andrew Morton
6db26ffc91 fs/ext4/inode.c: use pr_warn_ratelimited()
pr_warning_ratelimited() doesn't exist.

Also include printk.h, which defines these things.

Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:05 -08:00
Josef Bacik
d6dc8462f4 Ext4: fail if we try to use hole punch
Ext4 doesn't have the ability to punch holes yet, so make sure we return
EOPNOTSUPP if we try to use hole punching through fallocate.  This support can
be added later.  Thanks,

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:16:44 -05:00
Jan Kara
f00c9e44ad quota: Fix deadlock during path resolution
As Al Viro pointed out path resolution during Q_QUOTAON calls to quotactl
is prone to deadlocks. We hold s_umount semaphore for reading during the
path resolution and resolution itself may need to acquire the semaphore
for writing when e. g. autofs mountpoint is passed.

Solve the problem by performing the resolution before we get hold of the
superblock (and thus s_umount semaphore). The whole thing is complicated
by the fact that some filesystems (OCFS2) ignore the path argument. So to
distinguish between filesystem which want the path and which do not we
introduce new .quota_on_meta callback which does not get the path. OCFS2
then uses this callback instead of old .quota_on.

CC: Al Viro <viro@ZenIV.linux.org.uk>
CC: Christoph Hellwig <hch@lst.de>
CC: Ted Ts'o <tytso@mit.edu>
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-01-12 19:14:55 +01:00
Linus Torvalds
e9688f6aca Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits)
  ext4: fix trimming starting with block 0 with small blocksize
  ext4: revert buggy trim overflow patch
  ext4: don't pass entire map to check_eofblocks_fl
  ext4: fix memory leak in ext4_free_branches
  ext4: remove ext4_mb_return_to_preallocation()
  ext4: flush the i_completed_io_list during ext4_truncate
  ext4: add error checking to calls to ext4_handle_dirty_metadata()
  ext4: fix trimming of a single group
  ext4: fix uninitialized variable in ext4_register_li_request
  ext4: dynamically allocate the jbd2_inode in ext4_inode_info as necessary
  ext4: drop i_state_flags on architectures with 64-bit longs
  ext4: reorder ext4_inode_info structure elements to remove unneeded padding
  ext4: drop ec_type from the ext4_ext_cache structure
  ext4: use ext4_lblk_t instead of sector_t for logical blocks
  ext4: replace i_delalloc_reserved_flag with EXT4_STATE_DELALLOC_RESERVED
  ext4: fix 32bit overflow in ext4_ext_find_goal()
  ext4: add more error checks to ext4_mkdir()
  ext4: ext4_ext_migrate should use NULL not 0
  ext4: Use ext4_error_file() to print the pathname to the corrupted inode
  ext4: use IS_ERR() to check for errors in ext4_error_file
  ...
2011-01-11 14:37:31 -08:00
Jan Kara
0f0a25bf51 ext4: fix trimming starting with block 0 with small blocksize
When s_first_data_block is not zero (which happens e.g. when block size is 1KB)
and trim ioctl is called to start trimming from block 0, the math in
ext4_get_group_no_and_offset() overflows. The overall result is that ioctl
returns EINVAL which is kind of unexpected and we probably don't want
userspace tools to bother with internal details of filesystem structure.
So just silently increase starting offset (and shorten length) when starting
block is below s_first_data_block.

CC: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-11 15:16:31 -05:00
Theodore Ts'o
0a2179b169 ext4: revert buggy trim overflow patch
This reverts commit 4f531501e4: ext4: fix possible overflow in
ext4_trim_fs()

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-11 14:42:29 -05:00
Eric Sandeen
d002ebf1d8 ext4: don't pass entire map to check_eofblocks_fl
Since check_eofblocks_fl() only uses the m_lblk portion of the map
structure, we may as well pass that directly, rather than passing the
entire map, which IMHO obfuscates what parameters check_eofblocks_fl()
cares about.  Not a big deal, but seems tidier and less confusing, to
me.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 13:03:35 -05:00
Theodore Ts'o
1c5b9e9065 ext4: fix memory leak in ext4_free_branches
Commit 40389687 moved a call to ext4_forget() out of
ext4_free_branches and let ext4_free_blocks() handle calling
bforget().  But that change unfortunately did not replace the call to
ext4_forget() with brelse(), which was needed to drop the in-use count
of the indirect block's buffer head, which lead to a memory leak when
deleting files that used indirect blocks.  Fix this.

Thanks to Hugh Dickins for pointing this out.

Cc: stable@kernel.org
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:51:28 -05:00
Theodore Ts'o
a5196f8cdf ext4: remove ext4_mb_return_to_preallocation()
This function was never implemented, except for a BUG_ON which was
tripping when ext4 is run without a journal.  The problem is that
although the comment asserts that "truncate (which is the only way to
free block) discards all preallocations", ext4_free_blocks() is also
called in various error recovery paths when blocks have been
allocated, but for various reasons, we were not able to use those data
blocks (for example, because we ran out of memory while trying to
manipulate the extent tree, or some other similar situation).

In addition to the fact that this function isn't implemented except
for the incorrect BUG_ON, the single caller of this function,
ext4_free_blocks(), doesn't use it all if the journal is enabled.

So remove the (stub) function entirely for now.  If we decide it's
better to add it back, it's only going to be useful with a relatively
large number of code changes anyway.

Google-Bug-Id: 3236408

Cc: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:47:07 -05:00
Jiaying Zhang
3889fd57ea ext4: flush the i_completed_io_list during ext4_truncate
Ted first found the bug when running 2.6.36 kernel with dioread_nolock
mount option that xfstests #13 complained about wrong file size during fsck.
However, the bug exists in the older kernels as well although it is
somehow harder to trigger.

The problem is that ext4_end_io_work() can happen after we have truncated an
inode to a smaller size. Then when ext4_end_io_work() calls 
ext4_convert_unwritten_extents(), we may reallocate some blocks that have 
been truncated, so the inode size becomes inconsistent with the allocated
blocks. 

The following patch flushes the i_completed_io_list during truncate to reduce 
the risk that some pending end_io requests are executed later and convert 
already truncated blocks to initialized. 

Note that although the fix helps reduce the problem a lot there may still 
be a race window between vmtruncate() and ext4_end_io_work(). The fundamental
problem is that if vmtruncate() is called without either i_mutex or i_alloc_sem
held, it can race with an ongoing write request so that the io_end request is
processed later when the corresponding blocks have been truncated.

Ted and I have discussed the problem offline and we saw a few ways to fix
the race completely:

a) We guarantee that i_mutex lock and i_alloc_sem write lock are both hold 
whenever vmtruncate() is called. The i_mutex lock prevents any new write
requests from entering writeback and the i_alloc_sem prevents the race
from ext4_page_mkwrite(). Currently we hold both locks if vmtruncate()
is called from do_truncate(), which is probably the most common case.
However, there are places where we may call vmtruncate() without holding
either i_mutex or i_alloc_sem. I would like to ask for other people's
opinions on what locks are expected to be held before calling vmtruncate().
There seems a disagreement among the callers of that function.

b) We change the ext4 write path so that we change the extent tree to contain 
the newly allocated blocks and update i_size both at the same time --- when 
the write of the data blocks is completed.

c) We add some additional locking to synchronize vmtruncate() and 
ext4_end_io_work(). This approach may have performance implications so we
need to be careful.

All of the above proposals may require more substantial changes, so
we may consider to take the following patch as a bandaid.

Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:47:05 -05:00
Theodore Ts'o
b40971426a ext4: add error checking to calls to ext4_handle_dirty_metadata()
Call ext4_std_error() in various places when we can't bail out
cleanly, so the file system can be marked as in error.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:46:59 -05:00
Jan Kara
ca6e909f9b ext4: fix trimming of a single group
When ext4_trim_fs() is called to trim a part of a single group, the
logic will wrongly set last block of the interval to 'len' instead
of 'first_block + len'. Thus a shorter interval is possibly trimmed.
Fix it.

CC: Lukas Czerner <lczerner@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:30:39 -05:00
Andrew Morton
6c5a6cb998 ext4: fix uninitialized variable in ext4_register_li_request
fs/ext4/super.c: In function 'ext4_register_li_request':
fs/ext4/super.c:2936: warning: 'ret' may be used uninitialized in this function

It looks buggy to me, too.

Cc: Lukas Czerner <lczerner@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:30:17 -05:00
Theodore Ts'o
8aefcd557d ext4: dynamically allocate the jbd2_inode in ext4_inode_info as necessary
Replace the jbd2_inode structure (which is 48 bytes) with a pointer
and only allocate the jbd2_inode when it is needed --- that is, when
the file system has a journal present and the inode has been opened
for writing.  This allows us to further slim down the ext4_inode_info
structure.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:29:43 -05:00
Theodore Ts'o
353eb83c14 ext4: drop i_state_flags on architectures with 64-bit longs
We can store the dynamic inode state flags in the high bits of
EXT4_I(inode)->i_flags, and eliminate i_state_flags.  This saves 8
bytes from the size of ext4_inode_info structure, which when
multiplied by the number of the number of in the inode cache, can save
a lot of memory.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:18:25 -05:00
Theodore Ts'o
8a2005d3f8 ext4: reorder ext4_inode_info structure elements to remove unneeded padding
By reordering the elements in the ext4_inode_info structure, we can
reduce the padding needed on an x86_64 system by 16 bytes.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:13:42 -05:00
Theodore Ts'o
b05e6ae58a ext4: drop ec_type from the ext4_ext_cache structure
We can encode the ec_type information by using ee_len == 0 to denote
EXT4_EXT_CACHE_NO, ee_start == 0 to denote EXT4_EXT_CACHE_GAP, and if
neither is true, then the cache type must be EXT4_EXT_CACHE_EXTENT.
This allows us to reduce the size of ext4_ext_inode by another 8
bytes.  (ec_type is 4 bytes, plus another 4 bytes of padding)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:13:26 -05:00
Theodore Ts'o
01f49d0b9d ext4: use ext4_lblk_t instead of sector_t for logical blocks
This fixes a number of places where we used sector_t instead of
ext4_lblk_t for logical blocks, which for ext4 are still 32-bit data
types.  No point wasting space in the ext4_inode_info structure, and
requiring 64-bit arithmetic on 32-bit systems, when it isn't
necessary.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:13:03 -05:00
Theodore Ts'o
f232109773 ext4: replace i_delalloc_reserved_flag with EXT4_STATE_DELALLOC_RESERVED
Remove the short element i_delalloc_reserved_flag from the
ext4_inode_info structure and replace it a new bit in i_state_flags.
Since we have an ext4_inode_info for every ext4 inode cached in the
inode cache, any savings we can produce here is a very good thing from
a memory utilization perspective.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:12:36 -05:00
Kazuya Mio
ad4fb9cafe ext4: fix 32bit overflow in ext4_ext_find_goal()
ext4_ext_find_goal() returns an ideal physical block number that the block
allocator tries to allocate first. However, if a required file offset is
smaller than the existing extent's one, ext4_ext_find_goal() returns
a wrong block number because it may overflow at
"block - le32_to_cpu(ex->ee_block)". This patch fixes the problem.

ext4_ext_find_goal() will also return a wrong block number in case
a file offset of the existing extent is too big. In this case,
the ideal physical block number is fixed in ext4_mb_initialize_context(),
so it's no problem.

reproduce:
# dd if=/dev/zero of=/mnt/mp1/tmp bs=127M count=1 oflag=sync
# dd if=/dev/zero of=/mnt/mp1/file bs=512K count=1 seek=1 oflag=sync
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
 ext logical physical expected length flags
   0     128    67456             128 eof
/mnt/mp1/file: 2 extents found
# rm -rf /mnt/mp1/tmp
# echo $((512*4096)) > /sys/fs/ext4/loop0/mb_stream_req
# dd if=/dev/zero of=/mnt/mp1/file bs=512K count=1 oflag=sync conv=notrunc

result (linux-2.6.37-rc2 + ext4 patch queue):
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
 ext logical physical expected length flags
   0       0    33280             128 
   1     128    67456    33407    128 eof
/mnt/mp1/file: 2 extents found

result(apply this patch):
# filefrag -v /mnt/mp1/file
Filesystem type is: ef53
File size of /mnt/mp1/file is 1048576 (256 blocks, blocksize 4096)
 ext logical physical expected length flags
   0       0    66560             128 
   1     128    67456    66687    128 eof
/mnt/mp1/file: 2 extents found

Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:12:28 -05:00
Namhyung Kim
dabd991f9d ext4: add more error checks to ext4_mkdir()
Check return value of ext4_journal_get_write_access,
ext4_journal_dirty_metadata and ext4_mark_inode_dirty. Move brelse()
under 'out_stop' to release bh properly in case of journal error.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:11:16 -05:00
Eric Paris
f1dffc4c54 ext4: ext4_ext_migrate should use NULL not 0
ext4_ext_migrate() calls ext4_new_inode() and passes 0 instead of a pointer
to a struct qstr.  This patch uses NULL, to make it obvious to the caller
that this was a pointer.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:11:00 -05:00
Theodore Ts'o
f7c21177af ext4: Use ext4_error_file() to print the pathname to the corrupted inode
Where the file pointer is available, use ext4_error_file() instead of
ext4_error_inode().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:10:55 -05:00
Dan Carpenter
f9a62d090c ext4: use IS_ERR() to check for errors in ext4_error_file
d_path() returns an ERR_PTR and it doesn't return NULL.  This is in
ext4_error_file() and no one actually calls ext4_error_file().

Signed-off-by: Dan Carpenter <error27@gmail.com>
2011-01-10 12:10:50 -05:00
Dan Carpenter
13195184a8 ext4: test the correct variable in ext4_init_pageio()
This is a copy and paste error.  The intent was to check
"io_page_cachep".  We tested "io_page_cachep" earlier.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:10:44 -05:00
Wang Sheng-Hui
6e9510b0e0 ext2,ext3,ext4: clarify comment for extN_xattr_set_handle
Signed-off-by: Wang Sheng-Hui <crosslonelyover@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:10:30 -05:00
Theodore Ts'o
eaeef86718 ext4: clean up ext4_xattr_list()'s error code checking and return strategy
Any time you see code that tries to add error codes together, you
should want to claw your eyes out...

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10 12:10:07 -05:00
Lukas Czerner
9325963667 ext4: remove warning message from ext4_issue_discard helper
ext4_issue_discard is supposed to be helper for calling discard, however
in case that underlying device does not support discard it prints out
the warning message and clears the DISCARD t_mount_opt flag. Since it
can be (and is) used by others, it should not do anything and let the
caller to handle the error case.

This commit removes warning message and flag setting from
ext4_issue_discard and use it just in place where it is really needed
(release_blocks_on_commit). FITRIM ioctl should not set any flags nor it
should print out warning messages, so get rid of the warning as well.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
2011-01-10 12:09:59 -05:00