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  1. 06 6月, 2011 1 次提交
    • L
      ext4: Fix max file size and logical block counting of extent format file · f17722f9
      由 Lukas Czerner 提交于 
      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: NKazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      f17722f9
  3. 27 5月, 2011 1 次提交
    • D
      ext4: add cleancache support · 7abc52c2
      由 Dan Magenheimer 提交于 
      This seventh patch of eight in this cleancache series "opts-in"
cleancache for ext4.  Filesystems must explicitly enable cleancache
by calling cleancache_init_fs anytime an instance of the filesystem
is mounted. For ext4, all other cleancache hooks are in
the VFS layer including the matching cleancache_flush_fs
hook which must be called on unmount.

Details and a FAQ can be found in Documentation/vm/cleancache.txt

[v6-v8: no changes]
[v5: jeremy@goop.org: simplify init hook and any future fs init changes]
Signed-off-by: NDan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: NJeremy Fitzhardinge <jeremy@goop.org>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NAndreas Dilger <adilger@sun.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik Van Riel <riel@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
      7abc52c2
  5. 25 5月, 2011 2 次提交
    • J
      ext4: add support for multiple mount protection · c5e06d10
      由 Johann Lombardi 提交于 
      Prevent an ext4 filesystem from being mounted multiple times.
A sequence number is stored on disk and is periodically updated (every 5
seconds by default) by a mounted filesystem.
At mount time, we now wait for s_mmp_update_interval seconds to make sure
that the MMP sequence does not change.
In case of failure, the nodename, bdevname and the time at which the MMP
block was last updated is displayed.
Signed-off-by: NAndreas Dilger <adilger@whamcloud.com>
Signed-off-by: NJohann Lombardi <johann@whamcloud.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      c5e06d10
    • K
      ext4: ensure f_bfree returned by ext4_statfs() is non-negative · d02a9391
      由 Kazuya Mio 提交于 
      I found the issue that the number of free blocks went negative.
# stat -f /mnt/mp1/
  File: "/mnt/mp1/"
    ID: e175ccb83a872efe Namelen: 255     Type: ext2/ext3
Block size: 4096       Fundamental block size: 4096
Blocks: Total: 258022     Free: -15        Available: -13122
Inodes: Total: 65536      Free: 63029

f_bfree in struct statfs will go negative when the filesystem has
few free blocks. Because the number of dirty blocks is bigger than
the number of free blocks in the following two cases.

CASE 1:
ext4_da_writepages
  mpage_da_map_and_submit
    ext4_map_blocks
      ext4_ext_map_blocks
        ext4_mb_new_blocks
          ext4_mb_diskspace_used
            percpu_counter_sub(&sbi->s_freeblocks_counter, ac->ac_b_ex.fe_len);
        <--- interrupt statfs systemcall --->
        ext4_da_update_reserve_space
            percpu_counter_sub(&sbi->s_dirtyblocks_counter,
                            used + ei->i_allocated_meta_blocks);

CASE 2:
ext4_write_begin
  __block_write_begin
    ext4_map_blocks
      ext4_ext_map_blocks
        ext4_mb_new_blocks
          ext4_mb_diskspace_used
            percpu_counter_sub(&sbi->s_freeblocks_counter, ac->ac_b_ex.fe_len);
            <--- interrupt statfs systemcall --->
            percpu_counter_sub(&sbi->s_dirtyblocks_counter, reserv_blks);

To avoid the issue, this patch ensures that f_bfree is non-negative.
Signed-off-by: NKazuya Mio <k-mio@sx.jp.nec.com>
      d02a9391
  7. 23 5月, 2011 2 次提交
  9. 21 5月, 2011 4 次提交
  11. 19 5月, 2011 1 次提交
  13. 16 5月, 2011 1 次提交
  15. 09 5月, 2011 2 次提交
  17. 19 4月, 2011 1 次提交
    • T
      ext4: check for ext[23] file system features when mounting as ext[23] · 2035e776
      由 Theodore Ts'o 提交于 
      Provide better emulation for ext[23] mode by enforcing that the file
system does not have any unsupported file system features as defined
by ext[23] when emulating the ext[23] file system driver when
CONFIG_EXT4_USE_FOR_EXT23 is defined.

This causes the file system type information in /proc/mounts to be
correct for the automatically mounted root file system.  This also
means that "mount -t ext2 /dev/sda /mnt" will fail if /dev/sda
contains an ext3 or ext4 file system, just as one would expect if the
original ext2 file system driver were in use.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      2035e776
  19. 11 4月, 2011 1 次提交
  21. 06 4月, 2011 1 次提交
  23. 05 4月, 2011 2 次提交
  25. 31 3月, 2011 1 次提交
  27. 22 3月, 2011 1 次提交
  29. 15 3月, 2011 1 次提交
  31. 06 3月, 2011 1 次提交
  33. 28 2月, 2011 2 次提交
  35. 27 2月, 2011 1 次提交
  37. 24 2月, 2011 2 次提交
  39. 22 2月, 2011 2 次提交
  41. 12 2月, 2011 1 次提交
    • E
      ext4: serialize unaligned asynchronous DIO · e9e3bcec
      由 Eric Sandeen 提交于 
      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: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      e9e3bcec
  43. 04 2月, 2011 3 次提交
  45. 01 2月, 2011 1 次提交
  47. 13 1月, 2011 1 次提交
    • J
      quota: Fix deadlock during path resolution · f00c9e44
      由 Jan Kara 提交于 
      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: NJan Kara <jack@suse.cz>
      f00c9e44
  49. 11 1月, 2011 4 次提交