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  1. 11 10月, 2011 2 次提交
    • C
      Btrfs: make sure not to defrag extents past i_size · f7f43cc8
      由 Chris Mason 提交于 
      The btrfs file defrag code will loop through the extents and
force COW on them.  But there is a concurrent truncate in the middle of
the defrag, it might end up defragging the same range over and over
again.

The problem is that writepage won't go through and do anything on pages
past i_size, so the cow won't happen, so the file will appear to still
be fragmented.  defrag will end up hitting the same extents again and
again.

In the worst case, the truncate can actually live lock with the defrag
because the defrag keeps creating new ordered extents which the truncate
code keeps waiting on.

The fix here is to make defrag check for i_size inside the main loop,
instead of just once before the looping starts.
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      f7f43cc8
    • L
      Btrfs: fix recursive auto-defrag · 2a0f7f57
      由 Li Zefan 提交于 
      Follow those steps:

  # mount -o autodefrag /dev/sda7 /mnt
  # dd if=/dev/urandom of=/mnt/tmp bs=200K count=1
  # sync
  # dd if=/dev/urandom of=/mnt/tmp bs=8K count=1 conv=notrunc

and then it'll go into a loop: writeback -> defrag -> writeback ...

It's because writeback writes [8K, 200K] and then writes [0, 8K].

I tried to make writeback know if the pages are dirtied by defrag,
but the patch was a bit intrusive. Here I simply set writeback_index
when we defrag a file.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      2a0f7f57
  3. 01 10月, 2011 1 次提交
    • J
      Btrfs: force a page fault if we have a shorty copy on a page boundary · b6316429
      由 Josef Bacik 提交于 
      A user reported a problem where ceph was getting into 100% cpu usage while doing
some writing.  It turns out it's because we were doing a short write on a not
uptodate page, which means we'd fall back at one page at a time and fault the
page in.  The problem is our position is on the page boundary, so our fault in
logic wasn't actually reading the page, so we'd just spin forever or until the
page got read in by somebody else.  This will force a readpage if we end up
doing a short copy.  Alexandre could reproduce this easily with ceph and reports
it fixes his problem.  I also wrote a reproducer that no longer hangs my box
with this patch.  Thanks,
Reported-and-tested-by: NAlexandre Oliva <aoliva@redhat.com>
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      b6316429
  5. 21 9月, 2011 1 次提交
  7. 18 9月, 2011 4 次提交
    • L
      Btrfs: don't change inode flag of the dest clone file · dde820fb
      由 Li Zefan 提交于 
      The dst file will have the same inode flags with dst file after
file clone, and I think it's unexpected.

For example, the dst file will suddenly become immutable after
getting some share of data with src file, if the src is immutable.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      dde820fb
    • L
      Btrfs: don't make a file partly checksummed through file clone · 0e7b824c
      由 Li Zefan 提交于 
      To reproduce the bug:

  # mount /dev/sda7 /mnt
  # dd if=/dev/zero of=/mnt/src bs=4K count=1
  # umount /mnt

  # mount -o nodatasum /dev/sda7 /mnt
  # dd if=/dev/zero of=/mnt/dst bs=4K count=1
  # clone_range -s 4K -l 4K /mnt/src /mnt/dst

  # echo 3 > /proc/sys/vm/drop_caches
  # cat /mnt/dst
  # dmesg
  ...
  btrfs no csum found for inode 258 start 0
  btrfs csum failed ino 258 off 0 csum 2566472073 private 0

It's because part of the file is checksummed and the other part is not,
and then btrfs will complain checksum is not found when we read the file.

Disallow file clone if src and dst file have different checksum flag,
so we ensure a file is completely checksummed or unchecksummed.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      0e7b824c
    • L
      Btrfs: fix pages truncation in btrfs_ioctl_clone() · 71ef0786
      由 Li Zefan 提交于 
      It's a bug in commit f81c9cdc
(Btrfs: truncate pages from clone ioctl target range)

We should pass the dest range to the truncate function, but not the
src range.

Also move the function before locking extent state.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      71ef0786
    • H
      btrfs: fix d_off in the first dirent · 3765fefa
      由 Hidetoshi Seto 提交于 
      Since the d_off in the first dirent for "." (that originates from
the 4th argument "offset" of filldir() for the 2nd dirent for "..")
is wrongly assigned in btrfs_real_readdir(), telldir returns same
offset for different locations.

 | # mkfs.btrfs /dev/sdb1
 | # mount /dev/sdb1 fs0
 | # cd fs0
 | # touch file0 file1
 | # ../test
 | telldir: 0
 | readdir: d_off = 2, d_name = "."
 | telldir: 2
 | readdir: d_off = 2, d_name = ".."
 | telldir: 2
 | readdir: d_off = 3, d_name = "file0"
 | telldir: 3
 | readdir: d_off = 2147483647, d_name = "file1"
 | telldir: 2147483647

To fix this problem, pass filp->f_pos (which is loff_t) instead.

 | # ../test
 | telldir: 0
 | readdir: d_off = 1, d_name = "."
 | telldir: 1
 | readdir: d_off = 2, d_name = ".."
 | telldir: 2
 | readdir: d_off = 3, d_name = "file0"
 :

At the moment the "offset" for "." is unused because there is no
preceding dirent, however it is better to pass filp->f_pos to follow
grammatical usage.
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      3765fefa
  9. 11 9月, 2011 11 次提交
  11. 18 8月, 2011 1 次提交
  13. 17 8月, 2011 10 次提交
  15. 06 8月, 2011 1 次提交
  17. 02 8月, 2011 9 次提交