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  1. 16 5月, 2010 1 次提交
  3. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      由 Tejun Heo 提交于 
      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: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  5. 25 2月, 2010 1 次提交
  7. 16 2月, 2010 1 次提交
  9. 23 12月, 2009 3 次提交
  11. 18 12月, 2009 1 次提交
  13. 16 12月, 2009 1 次提交
  15. 10 12月, 2009 2 次提交
  17. 07 12月, 2009 1 次提交
    • T
      ext4: Use slab allocator for sub-page sized allocations · d2eecb03
      由 Theodore Ts'o 提交于 
      Now that the SLUB seems to be fixed so that it respects the requested
alignment, use kmem_cache_alloc() to allocator if the block size of
the buffer heads to be allocated is less than the page size.
Previously, we were using 16k page on a Power system for each buffer,
even when the file system was using 1k or 4k block size.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      d2eecb03
  19. 23 12月, 2009 1 次提交
  21. 01 12月, 2009 1 次提交
  23. 16 11月, 2009 1 次提交
    • T
      jbd2: don't wipe the journal on a failed journal checksum · e6a47428
      由 Theodore Ts'o 提交于 
      If there is a failed journal checksum, don't reset the journal.  This
allows for userspace programs to decide how to recover from this
situation.  It may be that ignoring the journal checksum failure might
be a better way of recovering the file system.  Once we add per-block
checksums, we can definitely do better.  Until then, a system
administrator can try backing up the file system image (or taking a
snapshot) and and trying to determine experimentally whether ignoring
the checksum failure or aborting the journal replay results in less
data loss.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
      e6a47428
  25. 11 11月, 2009 1 次提交
  27. 02 10月, 2009 1 次提交
  29. 30 9月, 2009 2 次提交
  31. 23 9月, 2009 1 次提交
  33. 16 9月, 2009 1 次提交
  35. 11 9月, 2009 1 次提交
    • T
      ext4: Fix async commit mode to be safe by using a barrier · 0e3d2a63
      由 Theodore Ts'o 提交于 
      Previously the journal_async_commit mount option was equivalent to
using barrier=0 (and just as unsafe).  This patch fixes it so that we
eliminate the barrier before the commit block (by not using ordered
mode), and explicitly issuing an empty barrier bio after writing the
commit block.  Because of the journal checksum, it is safe to do this;
if the journal blocks are not all written before a power failure, the
checksum in the commit block will prevent the last transaction from
being replayed.

Using the fs_mark benchmark, using journal_async_commit shows a 50%
improvement:

FSUse%        Count         Size    Files/sec     App Overhead
     8         1000        10240         30.5            28242

vs.

FSUse%        Count         Size    Files/sec     App Overhead
     8         1000        10240         45.8            28620
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      0e3d2a63
  37. 18 8月, 2009 1 次提交
  39. 11 8月, 2009 1 次提交
  41. 14 7月, 2009 1 次提交
    • D
      jbd2: fix race between write_metadata_buffer and get_write_access · 96577c43
      由 dingdinghua 提交于 
      The function jbd2_journal_write_metadata_buffer() calls
jbd_unlock_bh_state(bh_in) too early; this could potentially allow
another thread to call get_write_access on the buffer head, modify the
data, and dirty it, and allowing the wrong data to be written into the
journal.  Fortunately, if we lose this race, the only time this will
actually cause filesystem corruption is if there is a system crash or
other unclean shutdown of the system before the next commit can take
place.
Signed-off-by: Ndingdinghua <dingdinghua85@gmail.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      96577c43
  43. 17 7月, 2009 1 次提交
  45. 18 6月, 2009 1 次提交
  47. 14 7月, 2009 1 次提交
    • J
      jbd2: Fix a race between checkpointing code and journal_get_write_access() · f91d1d04
      由 Jan Kara 提交于 
      The following race can happen:

 CPU1                          CPU2
                               checkpointing code checks the buffer, adds
                                 it to an array for writeback
 do_get_write_access()
 ...
 lock_buffer()
 unlock_buffer()
                               flush_batch() submits the buffer for IO
 __jbd2_journal_file_buffer()

So a buffer under writeout is returned from
do_get_write_access(). Since the filesystem code relies on the fact
that journaled buffers cannot be written out, it does not take the
buffer lock and so it can modify buffer while it is under
writeout. That can lead to a filesystem corruption if we crash at the
right moment.

We fix the problem by clearing the buffer dirty bit under buffer_lock
even if the buffer is on BJ_None list. Actually, we clear the dirty
bit regardless the list the buffer is in and warn about the fact if
the buffer is already journalled.

Thanks for spotting the problem goes to dingdinghua <dingdinghua85@gmail.com>.
Reported-by: Ndingdinghua <dingdinghua85@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      f91d1d04
  49. 21 6月, 2009 1 次提交
  51. 09 6月, 2009 1 次提交
  53. 17 6月, 2009 1 次提交
  55. 14 4月, 2009 1 次提交
  57. 06 4月, 2009 1 次提交
  59. 28 3月, 2009 1 次提交
  61. 26 3月, 2009 1 次提交
  63. 11 2月, 2009 2 次提交
    • J
      jbd2: Avoid possible NULL dereference in jbd2_journal_begin_ordered_truncate() · 7f5aa215
      由 Jan Kara 提交于 
      If we race with commit code setting i_transaction to NULL, we could
possibly dereference it.  Proper locking requires the journal pointer
(to access journal->j_list_lock), which we don't have.  So we have to
change the prototype of the function so that filesystem passes us the
journal pointer.  Also add a more detailed comment about why the
function jbd2_journal_begin_ordered_truncate() does what it does and
how it should be used.

Thanks to Dan Carpenter <error27@gmail.com> for pointing to the
suspitious code.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Acked-by: NJoel Becker <joel.becker@oracle.com>
CC: linux-ext4@vger.kernel.org
CC: ocfs2-devel@oss.oracle.com
CC: mfasheh@suse.de
CC: Dan Carpenter <error27@gmail.com>
      7f5aa215
    • J
      jbd2: Fix return value of jbd2_journal_start_commit() · c88ccea3
      由 Jan Kara 提交于 
      The function jbd2_journal_start_commit() returns 1 if either a
transaction is committing or the function has queued a transaction
commit. But it returns 0 if we raced with somebody queueing the
transaction commit as well. This resulted in ext4_sync_fs() not
functioning correctly (description from Arthur Jones): 

   In the case of a data=ordered umount with pending long symlinks
   which are delayed due to a long list of other I/O on the backing
   block device, this causes the buffer associated with the long
   symlinks to not be moved to the inode dirty list in the second
   phase of fsync_super.  Then, before they can be dirtied again,
   kjournald exits, seeing the UMOUNT flag and the dirty pages are
   never written to the backing block device, causing long symlink
   corruption and exposing new or previously freed block data to
   userspace.

This can be reproduced with a script created by Eric Sandeen
<sandeen@redhat.com>:

        #!/bin/bash

        umount /mnt/test2
        mount /dev/sdb4 /mnt/test2
        rm -f /mnt/test2/*
        dd if=/dev/zero of=/mnt/test2/bigfile bs=1M count=512
        touch /mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
        ln -s /mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
        /mnt/test2/link
        umount /mnt/test2
        mount /dev/sdb4 /mnt/test2
        ls /mnt/test2/

This patch fixes jbd2_journal_start_commit() to always return 1 when
there's a transaction committing or queued for commit.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
CC: Eric Sandeen <sandeen@redhat.com>
CC: linux-ext4@vger.kernel.org
      c88ccea3
  65. 12 1月, 2009 1 次提交
    • S
      ext4: fix wrong use of do_div · c225aa57
      由 Simon Holm Thøgersen 提交于 
      the following warning:

fs/jbd2/journal.c: In function ‘jbd2_seq_info_show’:
fs/jbd2/journal.c:850: warning: format ‘%lu’ expects type ‘long
unsigned int’, but argument 3 has type ‘uint32_t’

is caused by wrong usage of do_div that modifies the dividend in-place
and returns the quotient. So not only would an incorrect value be
displayed, but s->journal->j_average_commit_time would also be changed
to a wrong value!

Fix it by using div_u64 instead.
Signed-off-by: NSimon Holm Thøgersen <odie@cs.aau.dk>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      c225aa57
  67. 07 1月, 2009 1 次提交
  69. 06 1月, 2009 1 次提交
    • J
      jbd2: Add buffer triggers · e06c8227
      由 Joel Becker 提交于 
      Filesystems often to do compute intensive operation on some
metadata.  If this operation is repeated many times, it can be very
expensive.  It would be much nicer if the operation could be performed
once before a buffer goes to disk.

This adds triggers to jbd2 buffer heads.  Just before writing a metadata
buffer to the journal, jbd2 will optionally call a commit trigger associated
with the buffer.  If the journal is aborted, an abort trigger will be
called on any dirty buffers as they are dropped from pending
transactions.

ocfs2 will use this feature.

Initially I tried to come up with a more generic trigger that could be
used for non-buffer-related events like transaction completion.  It
doesn't tie nicely, because the information a buffer trigger needs
(specific to a journal_head) isn't the same as what a transaction
trigger needs (specific to a tranaction_t or perhaps journal_t).  So I
implemented a buffer set, with the understanding that
journal/transaction wide triggers should be implemented separately.

There is only one trigger set allowed per buffer.  I can't think of any
reason to attach more than one set.  Contrast this with a journal or
transaction in which multiple places may want to watch the entire
transaction separately.

The trigger sets are considered static allocation from the jbd2
perspective.  ocfs2 will just have one trigger set per block type,
setting the same set on every bh of the same type.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>
      e06c8227