1. 13 5月, 2009 2 次提交
    • A
      ext4: Mark the unwritten buffer_head as mapped during write_begin · 29fa89d0
      Aneesh Kumar K.V 提交于
      Setting BH_Unwritten buffer_heads as BH_Mapped avoids multiple
      (unnecessary) calls to get_block() during the call to the write(2)
      system call.  Setting BH_Unwritten buffer heads as BH_Mapped requires
      that the writepages() functions can handle BH_Unwritten buffer_heads.
      
      After this commit, things work as follows:
      
      ext4_ext_get_block() returns unmapped, unwritten, buffer head when
      called with create = 0 for prealloc space. This makes sure we handle
      the read path and non-delayed allocation case correctly.  Even though
      the buffer head is marked unmapped we have valid b_blocknr and b_bdev
      values in the buffer_head.
      
      ext4_da_get_block_prep() called for block resrevation will now return
      mapped, unwritten, new buffer_head for prealloc space. This avoids
      multiple calls to get_block() for write to same offset. By making such
      buffers as BH_New, we also assure that sub-block zeroing of buffered
      writes happens correctly.
      Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      29fa89d0
    • A
      vfs: Add BUG_ON for delayed and unwritten flags in submit_bh() · 8fb0e342
      Aneesh Kumar K.V 提交于
      The BH_Delay and BH_Unwritten flags should never leak out to
      submit_bh().  So add some BUG_ON() checks to submit_bh so we can get a
      stack trace and determine how and why this might have happened.
      
      (Note that only XFS and ext4 use these buffer head flags, and XFS does
      not use submit_bh().  So this patch should only modify behavior for
      ext4.)
      Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      Cc: linux-fsdevel@vger.kernel.org
      8fb0e342
  2. 14 5月, 2009 1 次提交
  3. 03 6月, 2009 6 次提交
  4. 02 6月, 2009 9 次提交
  5. 01 6月, 2009 10 次提交
  6. 31 5月, 2009 3 次提交
  7. 30 5月, 2009 9 次提交