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  1. 05 3月, 2012 7 次提交
    • C
      ext4: don't release page refs in ext4_end_bio() · b43d17f3
      由 Curt Wohlgemuth 提交于 
      We can clear PageWriteback on each page when the IO
completes, but we can't release the references on the page
until we convert any uninitialized extents.

Without this patch, the use of the dioread_nolock mount
option can break buffered writes, because extents may
not be converted by the time a subsequent buffered read
comes in; if the page is not in the page cache, a read
will return zeros if the extent is still uninitialized.

I tested this with a (temporary) patch that adds a call
to msleep(1000) at the start of ext4_end_io_work(), to delay
processing of each DIO-unwritten work queue item.  With this
msleep(), a simple workload of

  fallocate
  write
  fadvise
  read

will fail without this patch, succeeds with it.
Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      b43d17f3
    • J
      ext4: fix race between sync and completed io work · 491caa43
      由 Jeff Moyer 提交于 
      The following command line will leave the aio-stress process unkillable
on an ext4 file system (in my case, mounted on /mnt/test):

aio-stress -t 20 -s 10 -O -S -o 2 -I 1000 /mnt/test/aiostress.3561.4 /mnt/test/aiostress.3561.4.20 /mnt/test/aiostress.3561.4.19 /mnt/test/aiostress.3561.4.18 /mnt/test/aiostress.3561.4.17 /mnt/test/aiostress.3561.4.16 /mnt/test/aiostress.3561.4.15 /mnt/test/aiostress.3561.4.14 /mnt/test/aiostress.3561.4.13 /mnt/test/aiostress.3561.4.12 /mnt/test/aiostress.3561.4.11 /mnt/test/aiostress.3561.4.10 /mnt/test/aiostress.3561.4.9 /mnt/test/aiostress.3561.4.8 /mnt/test/aiostress.3561.4.7 /mnt/test/aiostress.3561.4.6 /mnt/test/aiostress.3561.4.5 /mnt/test/aiostress.3561.4.4 /mnt/test/aiostress.3561.4.3 /mnt/test/aiostress.3561.4.2

This is using the aio-stress program from the xfstests test suite.
That particular command line tells aio-stress to do random writes to
20 files from 20 threads (one thread per file).  The files are NOT
preallocated, so you will get writes to random offsets within the
file, thus creating holes and extending i_size.  It also opens the
file with O_DIRECT and O_SYNC.

On to the problem.  When an I/O requires unwritten extent conversion,
it is queued onto the completed_io_list for the ext4 inode.  Two code
paths will pull work items from this list.  The first is the
ext4_end_io_work routine, and the second is ext4_flush_completed_IO,
which is called via the fsync path (and O_SYNC handling, as well).
There are two issues I've found in these code paths.  First, if the
fsync path beats the work routine to a particular I/O, the work
routine will free the io_end structure!  It does not take into account
the fact that the io_end may still be in use by the fsync path.  I've
fixed this issue by adding yet another IO_END flag, indicating that
the io_end is being processed by the fsync path.

The second problem is that the work routine will make an assignment to
io->flag outside of the lock.  I have witnessed this result in a hang
at umount.  Moving the flag setting inside the lock resolved that
problem.

The problem was introduced by commit b82e384c ("ext4: optimize
locking for end_io extent conversion"), which first appeared in 3.2.
As such, the fix should be backported to that release (probably along
with the unwritten extent conversion race fix).
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
CC: stable@kernel.org
      491caa43
    • J
      ext4: clean up the flags passed to __blockdev_direct_IO · 93ef8541
      由 Jeff Moyer 提交于 
      For extent-based files, you can perform DIO to holes, as mentioned in
the comments in ext4_ext_direct_IO.  However, that function passes
DIO_SKIP_HOLES to __blockdev_direct_IO, which is *really* confusing to
the uninitiated reader.  The key, here, is that the get_block function
passed in, ext4_get_block_write, completely ignores the create flag
that is passed to it (the create flag is passed in from the direct I/O
code, which uses the DIO_SKIP_HOLES flag to determine whether or not
it should be cleared).

This is a long-winded way of saying that the DIO_SKIP_HOLES flag is
ultimately ignored.  So let's remove it.
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      93ef8541
    • T
      ext4: try to deprecate noacl and noxattr_user mount options · f7048605
      由 Theodore Ts'o 提交于 
      No other file system allows ACL's and extended attributes to be
enabled or disabled via a mount option.  So let's try to deprecate
these options from ext4.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      f7048605
    • T
      ext4: ignore mount options supported by ext2/3 (but have since been removed) · c7198b9c
      由 Theodore Ts'o 提交于 
      Users who tried to use the ext4 file system driver is being used for
the ext2 or ext3 file systems (via the CONFIG_EXT4_USE_FOR_EXT23
option) could have failed mounts if their /etc/fstab contains options
recognized by ext2 or ext3 but which have since been removed in ext4.

So teach ext4 to recognize them and give a warning that the mount
option was removed.

Report: https://bbs.archlinux.org/profile.php?id=33804Signed-off-by: NTom Gundersen <teg@jklm.no>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Baechler <thomas@archlinux.org>
Cc: Tobias Powalowski <tobias.powalowski@googlemail.com>
Cc: Dave Reisner <d@falconindy.com>
      c7198b9c
    • T
      ext4: add debugging /proc file showing file system options · 66acdcf4
      由 Theodore Ts'o 提交于 
      Now that /proc/mounts is consistently showing only those mount options
which need to be specified in /etc/fstab or on the mount command line,
it is useful to have file which shows exactly which file system
options are enabled.  This can be useful when debugging a user
problem.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      66acdcf4
    • T
      ext4: make ext4_show_options() be table-driven · 5a916be1
      由 Theodore Ts'o 提交于 
      Consistently show mount options which are the non-default, so that
/proc/mounts accurately shows the mount options that would be
necessary to mount the file system in its current mode of operation.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      5a916be1
  3. 04 3月, 2012 4 次提交
  5. 03 3月, 2012 2 次提交
  7. 02 3月, 2012 1 次提交
  9. 27 2月, 2012 1 次提交
  11. 21 2月, 2012 21 次提交
  13. 07 2月, 2012 1 次提交
  15. 01 2月, 2012 2 次提交
    • L
      Linux 3.3-rc2 · 62aa2b53
      由 Linus Torvalds 提交于
      62aa2b53
    • L
      Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream · d3712b9d
      由 Linus Torvalds 提交于 
      There are few important bug fixes for LogFS

* tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream:
  Logfs: Allow NULL block_isbad() methods
  logfs: Grow inode in delete path
  logfs: Free areas before calling generic_shutdown_super()
  logfs: remove useless BUG_ON
  MAINTAINERS: Add Prasad Joshi in LogFS maintiners
  logfs: Propagate page parameter to __logfs_write_inode
  logfs: set superblock shutdown flag after generic sb shutdown
  logfs: take write mutex lock during fsync and sync
  logfs: Prevent memory corruption
  logfs: update page reference count for pined pages

Fix up conflict in fs/logfs/dev_mtd.c due to semantic change in what
"mtd->block_isbad" means in commit f2933e86: "Logfs: Allow NULL
block_isbad() methods" clashing with the abstraction changes in the
commits 7086c19d: "mtd: introduce mtd_block_isbad interface" and
d58b27ed: "logfs: do not use 'mtd->block_isbad' directly".

This resolution takes the semantics from commit f2933e86, and just
makes mtd_block_isbad() return zero (false) if the 'block_isbad'
function is NULL.  But that also means that now "mtd_can_have_bb()"
always returns 0.

Now, "mtd_block_markbad()" will obviously return an error if the
low-level driver doesn't support bad blocks, so this is somewhat
non-symmetric, but it actually makes sense if a NULL "block_isbad"
function is considered to mean "I assume that all my blocks are always
good".
      d3712b9d
  17. 31 1月, 2012 1 次提交