Commit Graph

47 Commits

Author SHA1 Message Date
Linus Torvalds d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Zheng Liu 69eb33dc24 ext4: remove single extent cache
Single extent cache could be removed because we have extent status tree
as a extent cache, and it would be better.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:31:07 -05:00
Theodore Ts'o 9924a92a8c ext4: pass context information to jbd2__journal_start()
So we can better understand what bits of ext4 are responsible for
long-running jbd2 handles, use jbd2__journal_start() so we can pass
context information for logging purposes.

The recommended way for finding the longer-running handles is:

   T=/sys/kernel/debug/tracing
   EVENT=$T/events/jbd2/jbd2_handle_stats
   echo "interval > 5" > $EVENT/filter
   echo 1 > $EVENT/enable

   ./run-my-fs-benchmark

   cat $T/trace > /tmp/problem-handles

This will list handles that were active for longer than 20ms.  Having
longer-running handles is bad, because a commit started at the wrong
time could stall for those 20+ milliseconds, which could delay an
fsync() or an O_SYNC operation.  Here is an example line from the
trace file describing a handle which lived on for 311 jiffies, or over
1.2 seconds:

postmark-2917  [000] ....   196.435786: jbd2_handle_stats: dev 254,32 
   tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1
   dirtied_blocks 0

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-08 21:59:22 -05:00
Akria Fujita 87e698734b ext4: fix smatch warning in move_extent.c's mext_replace_branches()
Commit 2147b1a6a4 resulted in a new smatch warning:

> fs/ext4/move_extent.c:693 mext_replace_branches()
> 	 warn: variable dereferenced before check 'dext' (see line 683)

Fix this by adding a check to make sure dext is non-NULL before we
derefrence it.

Signed-off-by: Akria Fujita <a-fujita@rs.jp.nec.com>
[ modified by tytso to make sure an ext4_error is called ]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-01 20:52:46 -05:00
Theodore Ts'o 4a092d7379 ext4: rationalize ext4_extents.h inclusion
Previously, ext4_extents.h was being included at the end of ext4.h,
which was bad for a number of reasons: (a) it was not being included
in the expected place, and (b) it caused the header to be included
multiple times.  There were #ifdef's to prevent this from causing any
problems, but it still was unnecessary.

By moving the function declarations that were in ext4_extents.h to
ext4.h, which is standard practice for where the function declarations
for the rest of ext4.h can be found, we can remove ext4_extents.h from
being included in ext4.h at all, and then we can only include
ext4_extents.h where it is needed in ext4's source files.

It should be possible to move a few more things into ext4.h, and
further reduce the number of source files that need to #include
ext4_extents.h, but that's a cleanup for another day.

Reported-by: Sachin Kamat <sachin.kamat@linaro.org>
Reported-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-28 13:03:30 -05:00
Dmitry Monakhov 17335dcc47 ext4: serialize dio nonlocked reads with defrag workers
Inode's block defrag and ext4_change_inode_journal_flag() may
affect nonlocked DIO reads result, so proper synchronization
required.

- Add missed inode_dio_wait() calls where appropriate
- Check inode state under extra i_dio_count reference.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 00:41:21 -04:00
Wei Yongjun ba39ebb614 ext4: convert to use leXX_add_cpu()
Convert cpu_to_leXX(leXX_to_cpu(E1) + E2) to use leXX_add_cpu().

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-27 09:37:53 -04:00
Wang Sheng-Hui cbb4ee830e ext4: remove redundant offset check in mext_check_arguments()
In the check code above, if orig_start != donor_start, we would
return -EINVAL. So here, orig_start should be equal with donor_start.
Remove the redundant check here.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-27 08:00:01 -04:00
Dmitry Monakhov 8c85447391 ext4: reimplement uninit extent optimization for move_extent_per_page()
Uninitialized extent may became initialized(parallel writeback task)
at any moment after we drop i_data_sem, so we have to recheck extent's
state after we hold page's lock and i_data_sem.

If we about to change page's mapping we must hold page's lock in order to
serialize other users.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-26 12:54:52 -04:00
Dmitry Monakhov bb55748805 ext4: clean up online defrag bugs in move_extent_per_page()
Non-full list of bugs:
1) uninitialized extent optimization does not hold page's lock,
   and simply replace brunches after that writeback code goes
   crazy because block mapping changed under it's feets
   kernel BUG at fs/ext4/inode.c:1434!  ( 288'th xfstress)

2) uninitialized extent may became initialized right after we
   drop i_data_sem, so extent state must be rechecked

3) Locked pages goes uptodate via following sequence:
   ->readpage(page); lock_page(page); use_that_page(page)
   But after readpage() one may invalidate it because it is
   uptodate and unlocked (reclaimer does that)
   As result kernel bug at include/linux/buffer_head.c:133!

4) We call write_begin() with already opened stansaction which
   result in following deadlock:
->move_extent_per_page()
  ->ext4_journal_start()-> hold journal transaction
  ->write_begin()
    ->ext4_da_write_begin()
      ->ext4_nonda_switch()
        ->writeback_inodes_sb_if_idle()  --> will wait for journal_stop()

5) try_to_release_page() may fail and it does fail if one of page's bh was
   pinned by journal

6) If we about to change page's mapping we MUST hold it's lock during entire
   remapping procedure, this is true for both pages(original and donor one)

Fixes:

- Avoid (1) and (2) simply by temproraly drop uninitialized extent handling
  optimization, this will be reimplemented later.

- Fix (3) by manually forcing page to uptodate state w/o dropping it's lock

- Fix (4) by rearranging existing locking:
  from: journal_start(); ->write_begin
  to: write_begin(); journal_extend()
- Fix (5) simply by checking retvalue
- Fix (6) by locking both (original and donor one) pages during extent swap
  with help of mext_page_double_lock()

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-26 12:52:07 -04:00
Dmitry Monakhov f066055a34 ext4: online defrag is not supported for journaled files
Proper block swap for inodes with full journaling enabled is
truly non obvious task. In order to be on a safe side let's
explicitly disable it for now.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-09-26 12:32:54 -04:00
Dmitry Monakhov 03bd8b9b89 ext4: move_extent code cleanup
- Remove usless checks, because it is too late to check that inode != NULL
  at the moment it was referenced several times.
- Double lock routines looks very ugly and locking ordering relays on
  order of i_ino, but other kernel code rely on order of pointers.
  Let's make them simple and clean.
- check that inodes belongs to the same SB as soon as possible.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-09-26 12:32:19 -04:00
Aditya Kali d8990240d8 ext4: add some tracepoints in ext4/extents.c
This patch adds some tracepoints in ext4/extents.c and updates a tracepoint in
ext4/inode.c.

Tested: Built and ran the kernel and verified that these tracepoints work.
Also ran xfstests.

Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:18:51 -04:00
Lukas Czerner f17722f917 ext4: Fix max file size and logical block counting of extent format file
Kazuya Mio reported that he was able to hit BUG_ON(next == lblock)
in ext4_ext_put_gap_in_cache() while creating a sparse file in extent
format and fill the tail of file up to its end. We will hit the BUG_ON
when we write the last block (2^32-1) into the sparse file.

The root cause of the problem lies in the fact that we specifically set
s_maxbytes so that block at s_maxbytes fit into on-disk extent format,
which is 32 bit long. However, we are not storing start and end block
number, but rather start block number and length in blocks. It means
that in order to cover extent from 0 to EXT_MAX_BLOCK we need
EXT_MAX_BLOCK+1 to fit into len (because we counting block 0 as well) -
and it does not.

The only way to fix it without changing the meaning of the struct
ext4_extent members is, as Kazuya Mio suggested, to lower s_maxbytes
by one fs block so we can cover the whole extent we can get by the
on-disk extent format.

Also in many places EXT_MAX_BLOCK is used as length instead of maximum
logical block number as the name suggests, it is all a bit messy. So
this commit renames it to EXT_MAX_BLOCKS and change its usage in some
places to actually be maximum number of blocks in the extent.

The bug which this commit fixes can be reproduced as follows:

 dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-2))
 sync
 dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-1))

Reported-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-06-06 00:05:17 -04:00
Darrick J. Wong 7cb1a5351d ext4: clean up some wait_on_page_writeback calls
wait_on_page_writeback already checks the writeback bit, so callers of it
needn't do that test.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-05-18 13:53:20 -04:00
Theodore Ts'o bf89d16f6e ext4: rename {ext,idx}_pblock and inline small extent functions
Cleanup namespace leaks from fs/ext4 and the inline trivial functions
ext4_{ext,idx}_pblock() and ext4_{ext,idx}_store_pblock() since the
code size actually shrinks when we make these functions inline,
they're so trivial.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 21:30:14 -04:00
Theodore Ts'o c398eda0e4 ext4: Pass line numbers to ext4_error() and friends
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-07-27 11:56:40 -04:00
Theodore Ts'o 1f5a81e41f ext4: Make sure the MOVE_EXT ioctl can't overwrite append-only files
Dan Roseberg has reported a problem with the MOVE_EXT ioctl.  If the
donor file is an append-only file, we should not allow the operation
to proceed, lest we end up overwriting the contents of an append-only
file.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Dan Rosenberg <dan.j.rosenberg@gmail.com>
2010-06-02 22:04:39 -04:00
Dmitry Monakhov 12e9b89200 ext4: Use bitops to read/modify i_flags in struct ext4_inode_info
At several places we modify EXT4_I(inode)->i_flags without holding
i_mutex (ext4_do_update_inode, ...). These modifications are racy and
we can lose updates to i_flags. So convert handling of i_flags to use
bitops which are atomic.

https://bugzilla.kernel.org/show_bug.cgi?id=15792

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-05-16 22:00:00 -04:00
Theodore Ts'o 24676da469 ext4: Convert calls of ext4_error() to EXT4_ERROR_INODE()
EXT4_ERROR_INODE() tends to provide better error information and in a
more consistent format.  Some errors were not even identifying the inode
or directory which was corrupted, which made them not very useful.

Addresses-Google-Bug: #2507977

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-05-16 21:00:00 -04:00
Steven Liu c26d0bad3d ext4: Fix coding style in fs/ext4/move_extent.c
Making sure ee_block is initialized to zero to prevent gcc from
kvetching.  It's harmless (although it's not obvious that it's
harmless) from code inspection:

fs/ext4/move_extent.c:478: warning: 'start_ext.ee_block' may be used
uninitialized in this function

Thanks to Stefan Richter for first bringing this to the attention of
linux-ext4@vger.kernel.org.

Signed-off-by: LiuQi <lingjiujianke@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-05-11 00:00:00 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Akira Fujita c437b27335 ext4: Code cleanup for EXT4_IOC_MOVE_EXT ioctl
a) Fix sparse warning in ext4_ioctl()
b) Remove unneeded variable in mext_leaf_block()
c) Fix spelling typo in mext_check_arguments()

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-03-04 00:39:24 -05:00
Akira Fujita 7247c0caa2 ext4: Fix the NULL reference in double_down_write_data_sem()
If EXT4_IOC_MOVE_EXT ioctl is called with NULL donor_fd, fget() in
ext4_ioctl() gets inappropriate file structure for donor; so we need
to do this check earlier, before calling double_down_write_data_sem().

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-03-04 00:34:58 -05:00
Akira Fujita 5fd5249aa3 ext4: Fix insertion point of extent in mext_insert_across_blocks()
If the leaf node has 2 extent space or fewer and EXT4_IOC_MOVE_EXT
ioctl is called with the file offset where after the 2nd extent
covers, mext_insert_across_blocks() always tries to insert extent into
the first extent.  As a result, the file gets corrupted because of
wrong extent order.  The patch fixes this problem.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-03-04 00:31:06 -05:00
Eric Sandeen 12062dddda ext4: move __func__ into a macro for ext4_warning, ext4_error
Just a pet peeve of mine; we had a mishash of calls with either __func__
or "function_name" and the latter tends to get out of sync.

I think it's easier to just hide the __func__ in a macro, and it'll
be consistent from then on.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-02-15 14:19:27 -05:00
Akira Fujita 4a58579b9e ext4: Fix insufficient checks in EXT4_IOC_MOVE_EXT
This patch fixes three problems in the handling of the
EXT4_IOC_MOVE_EXT ioctl:

1. In current EXT4_IOC_MOVE_EXT, there are read access mode checks for
original and donor files, but they allow the illegal write access to
donor file, since donor file is overwritten by original file data.  To
fix this problem, change access mode checks of original (r->r/w) and
donor (r->w) files.

2.  Disallow the use of donor files that have a setuid or setgid bits.

3.  Call mnt_want_write() and mnt_drop_write() before and after
ext4_move_extents() calling to get write access to a mount.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-12-06 23:38:31 -05:00
Akira Fujita ac48b0a1d0 ext4: move_extent_per_page() cleanup
Integrate duplicate lines (acquire/release semaphore and invalidate
extent cache in move_extent_per_page()) into mext_replace_branches(),
to reduce source and object code size.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-24 10:31:56 -05:00
Kazuya Mio 446aaa6e7e ext4: initialize moved_len before calling ext4_move_extents()
The move_extent.moved_len is used to pass back the number of exchanged
blocks count to user space.  Currently the caller must clear this
field; but we spend more code space checking for this requirement than
simply zeroing the field ourselves, so let's just make life easier for
everyone all around.

Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-24 10:28:48 -05:00
Akira Fujita 94d7c16cbb ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT
At the beginning of ext4_move_extent(), we call
ext4_discard_preallocations() to discard inode PAs of orig and donor
inodes.  But in the following case, blocks can be double freed, so
move ext4_discard_preallocations() to the end of ext4_move_extents().

1. Discard inode PAs of orig and donor inodes with
   ext4_discard_preallocations() in ext4_move_extents().

   orig : [ DATA1 ]
   donor: [ DATA2 ]

2. While data blocks are exchanging between orig and donor inodes, new
   inode PAs is created to orig by other process's block allocation.
   (Since there are semaphore gaps in ext4_move_extents().)  And new
   inode PAs is used partially (2-1).

   2-1 Create new inode PAs to orig inode
   orig : [ DATA1 | used PA1 | free PA1 ]
   donor: [ DATA2 ]

3. Donor inode which has old orig inode's blocks is deleted after
   EXT4_IOC_MOVE_EXT finished (3-1, 3-2).  So the block bitmap
   corresponds to old orig inode's blocks are freed.

   3-1 After EXT4_IOC_MOVE_EXT finished
   orig : [ DATA2 |  free PA1 ]
   donor: [ DATA1 |  used PA1 ]

   3-2 Delete donor inode
   orig : [ DATA2 |  free PA1 ]
   donor: [ FREE SPACE(DATA1) | FREE SPACE(used PA1) ]

4. The double-free of blocks is occurred, when close() is called to
   orig inode.  Because ext4_discard_preallocations() for orig inode
   frees used PA1 and free PA1, though used PA1 is already freed in 3.

   4-1 Double-free of blocks is occurred
   orig : [ DATA2 |  FREE SPACE(free PA1) ]
   donor: [ FREE SPACE(DATA1) | DOUBLE FREE(used PA1) ]

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-24 10:19:57 -05:00
Akira Fujita 92c28159dc ext4: fix spelling typos in move_extent.c
Fix a few spelling typos in move_extent.c

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.co.jp>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-23 07:24:50 -05:00
Akira Fujita 49bd22bc4d ext4: fix possible recursive locking warning in EXT4_IOC_MOVE_EXT
If CONFIG_PROVE_LOCKING is enabled, the double_down_write_data_sem()
will trigger a false-positive warning of a recursive lock.  Since we
take i_data_sem for the two inodes ordered by their inode numbers,
this isn't a problem.  Use of down_write_nested() will notify the lock
dependency checker machinery that there is no problem here.

This problem was reported by Brian Rogers:

	http://marc.info/?l=linux-ext4&m=125115356928011&w=1

Reported-by: Brian Rogers <brian@xyzw.org>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-23 07:24:41 -05:00
Akira Fujita fc04cb49a8 ext4: fix lock order problem in ext4_move_extents()
ext4_move_extents() checks the logical block contiguousness
of original file with ext4_find_extent() and mext_next_extent().
Therefore the extent which ext4_ext_path structure indicates
must not be changed between above functions.

But in current implementation, there is no i_data_sem protection
between ext4_ext_find_extent() and mext_next_extent().  So the extent
which ext4_ext_path structure indicates may be overwritten by
delalloc.  As a result, ext4_move_extents() will exchange wrong blocks
between original and donor files.  I change the place where
acquire/release i_data_sem to solve this problem.

Moreover, I changed move_extent_per_page() to start transaction first,
and then acquire i_data_sem.  Without this change, there is a
possibility of the deadlock between mmap() and ext4_move_extents():

* NOTE: "A", "B" and "C" mean different processes

A-1: ext4_ext_move_extents() acquires i_data_sem of two inodes.

B:   do_page_fault() starts the transaction (T),
     and then tries to acquire i_data_sem.
     But process "A" is already holding it, so it is kept waiting.

C:   While "A" and "B" running, kjournald2 tries to commit transaction (T)
     but it is under updating, so kjournald2 waits for it.

A-2: Call ext4_journal_start with holding i_data_sem,
     but transaction (T) is locked.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-23 07:24:43 -05:00
Akira Fujita f868a48d06 ext4: fix the returned block count if EXT4_IOC_MOVE_EXT fails
If the EXT4_IOC_MOVE_EXT ioctl fails, the number of blocks that were
exchanged before the failure should be returned to the userspace
caller.  Unfortunately, currently if the block size is not the same as
the page size, the returned block count that is returned is the
page-aligned block count instead of the actual block count.  This
commit addresses this bug.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-23 07:25:48 -05:00
Theodore Ts'o f3ce8064b3 ext4: EXT4_IOC_MOVE_EXT: Check for different original and donor inodes first
Move the check to make sure the original and donor inodes are
different earlier, to avoid a potential deadlock by trying to lock the
same inode twice.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-28 15:58:29 -04:00
Mingming Cao 0031462b5b ext4: Split uninitialized extents for direct I/O
When writing into an unitialized extent via direct I/O, and the direct
I/O doesn't exactly cover the unitialized extent, split the extent
into uninitialized and initialized extents before submitting the I/O.
This avoids needing to deal with an ENOSPC error in the end_io
callback that gets used for direct I/O.

When the IO is complete, the written extent will be marked as initialized.

Singed-Off-By: Mingming Cao <cmm@us.ibm.com> 
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-28 15:49:08 -04:00
Eric Sandeen 0a80e9867d ext4: replace MAX_DEFRAG_SIZE with EXT_MAX_BLOCK
There's no reason to redefine the maximum allowable offset
in an extent-based file just for defrag; 
EXT_MAX_BLOCK already does this.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-17 11:55:58 -04:00
Akira Fujita c40ce3c9ea ext4: Fix different block exchange issue in EXT4_IOC_MOVE_EXT
If logical block offset of original file which is passed to
EXT4_IOC_MOVE_EXT is different from donor file's,
a calculation error occurs in ext4_calc_swap_extents(),
therefore wrong block is exchanged between original file and donor file.
As a result, we hit ext4_error() in check_block_validity().
To detect the logical offset difference in EXT4_IOC_MOVE_EXT,
add checks to mext_calc_swap_extents() and handle it as error,
since data exchange must be done between the same blocks in EXT4_IOC_MOVE_EXT.

Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:25:39 -04:00
Akira Fujita 347fa6f1c7 ext4: Add null extent check to ext_get_path
There is the possibility that path structure which is taken
by ext4_ext_find_extent() indicates null extents.
Because during data block exchanging in ext4_move_extents(),
constitution of an extent tree may be changed.
As a solution, the patch adds null extent check
to ext_get_path().

Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:25:07 -04:00
Akira Fujita 2147b1a6a4 ext4: Replace BUG_ON() with ext4_error() in move_extents.c
Replace BUG_ON calls with a call to ext4_error()
to print an error message if EXT4_IOC_MOVE_EXT failed
with some kind of reasons.  This will help to debug.
Ted pointed this out, thanks.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 13:46:35 -04:00
Akira Fujita e8505970af ext4: Replace get_ext_path macro with an inline funciton
Replace get_ext_path macro with an inline function,
since this macro looks like a function call but its arguments
get modified. Ted pointed this out, thanks.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 13:46:38 -04:00
Akira Fujita 44fc48f704 ext4: Fix small typo for move_extent_per_page()
This function means moving extents every page, so change its name from
move_exgtent_par_page().

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.co.jp>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-05 23:12:41 -04:00
Akira Fujita daea696dba ext4: Remove unneeded BUG_ON() in ext4_move_extents()
The ext4_move_extents() functions checks with BUG_ON() whether the
exchanged blocks count accords with request blocks count.  But, if the
target range (orig_start + len) includes sparse block(s), 'moved_len'
(exchanged blocks count) does not agree with 'len' (request blocks
count), since sparse block is not counted in 'moved_len'.  This causes
us to hit the BUG_ON(), even though the function succeeded.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-05 22:11:55 -04:00
Akira Fujita 70d5d3dcea ext4: Fix wrong comparisons in mext_check_arguments()
The mext_check_arguments() function in move_extents.c has wrong
comparisons.  orig_start which is passed from user-space is block
unit, but i_size of inode is byte unit, therefore the checks do not
work fine.  This mis-check leads to the overflow of 'len' and then
hits BUG_ON() in ext4_move_extents().  The patch fixes this issue.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Reviewed-by: Greg Freemyer <greg.freemyer@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-09-16 14:28:22 -04:00
Peng Tao 91cc219ad9 ext4: fix journal ref count in move_extent_par_page
move_extent_par_page calls a_ops->write_begin() to increase journal
handler's reference count. However, if either mext_replace_branches()
or ext4_get_block fails, the increased reference count isn't
decreased. This will cause a later attempt to umount of the fs to hang
forever. The patch addresses the issue by calling ext4_journal_stop()
if page is not NULL (which means a_ops->write_end() isn't invoked).

Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-08-10 23:05:28 -04:00
Akira Fujita 748de6736c ext4: online defrag -- Add EXT4_IOC_MOVE_EXT ioctl
The EXT4_IOC_MOVE_EXT exchanges the blocks between orig_fd and donor_fd,
and then write the file data of orig_fd to donor_fd.
ext4_mext_move_extent() is the main fucntion of ext4 online defrag,
and this patch includes all functions related to ext4 online defrag.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: Takashi Sato <t-sato@yk.jp.nec.com>
Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-06-17 19:24:03 -04:00