ext4_da_convert_inline_data_to_extent-drop-locked-page-after-error

   1 ext4: ext4_da_convert_inline_data_to_extent drop locked page after error
   2
   3 From: Dmitry Monakhov <dmonakhov@openvz.org>
   4
   5 Testcase:
   6 xfstests generic/270
   7 MKFS_OPTIONS="-q -I 256 -O inline_data,64bit"
   8
   9 Call Trace:
  10  [<ffffffff81144c76>] lock_page+0x35/0x39 -------> DEADLOCK
  11  [<ffffffff81145260>] pagecache_get_page+0x65/0x15a
  12  [<ffffffff811507fc>] truncate_inode_pages_range+0x1db/0x45c
  13  [<ffffffff8120ea63>] ? ext4_da_get_block_prep+0x439/0x4b6
  14  [<ffffffff811b29b7>] ? __block_write_begin+0x284/0x29c
  15  [<ffffffff8120e62a>] ? ext4_change_inode_journal_flag+0x16b/0x16b
  16  [<ffffffff81150af0>] truncate_inode_pages+0x12/0x14
  17  [<ffffffff81247cb4>] ext4_truncate_failed_write+0x19/0x25
  18  [<ffffffff812488cf>] ext4_da_write_inline_data_begin+0x196/0x31c
  19  [<ffffffff81210dad>] ext4_da_write_begin+0x189/0x302
  20  [<ffffffff810c07ac>] ? trace_hardirqs_on+0xd/0xf
  21  [<ffffffff810ddd13>] ? read_seqcount_begin.clone.1+0x9f/0xcc
  22  [<ffffffff8114309d>] generic_perform_write+0xc7/0x1c6
  23  [<ffffffff810c040e>] ? mark_held_locks+0x59/0x77
  24  [<ffffffff811445d1>] __generic_file_write_iter+0x17f/0x1c5
  25  [<ffffffff8120726b>] ext4_file_write_iter+0x2a5/0x354
  26  [<ffffffff81185656>] ? file_start_write+0x2a/0x2c
  27  [<ffffffff8107bcdb>] ? bad_area_nosemaphore+0x13/0x15
  28  [<ffffffff811858ce>] new_sync_write+0x8a/0xb2
  29  [<ffffffff81186e7b>] vfs_write+0xb5/0x14d
  30  [<ffffffff81186ffb>] SyS_write+0x5c/0x8c
  31  [<ffffffff816f2529>] system_call_fastpath+0x12/0x17
  32
  33 Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
  34 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  35 ---
  36  fs/ext4/inline.c |    5 ++++-
  37  1 files changed, 4 insertions(+), 1 deletions(-)
  38
  39 changes from V1
  40  - drop xattr_sem before ext4_truncate_failed_write() because
  41    ext4_inline_data_truncate() depends on it.
  42
  43 diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
  44 index d3d8192..acd79b7 100644
  45 --- a/fs/ext4/inline.c
  46 +++ b/fs/ext4/inline.c
  47 @@ -811,8 +811,11 @@ static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
  48         ret = __block_write_begin(page, 0, inline_size,
  49                                   ext4_da_get_block_prep);
  50         if (ret) {
  51 +               up_read(&EXT4_I(inode)->xattr_sem);
  52 +               unlock_page(page);
  53 +               page_cache_release(page);
  54                 ext4_truncate_failed_write(inode);
  55 -               goto out;
  56 +               return ret;
  57         }
  58
  59         SetPageDirty(page);