• Aneesh Kumar K.V's avatar
    ext4: Clear the unwritten buffer_head flag after the extent is initialized · 2a8964d6
    Aneesh Kumar K.V authored
    The BH_Unwritten flag indicates that the buffer is allocated on disk
    but has not been written; that is, the disk was part of a persistent
    preallocation area.  That flag should only be set when a get_blocks()
    function is looking up a inode's logical to physical block mapping.
    
    When ext4_get_blocks_wrap() is called with create=1, the uninitialized
    extent is converted into an initialized one, so the BH_Unwritten flag
    is no longer appropriate.  Hence, we need to make sure the
    BH_Unwritten is not left set, since the combination of BH_Mapped and
    BH_Unwritten is not allowed; among other things, it will result ext4's
    get_block() to be called over and over again during the write_begin
    phase of write(2).
    Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
    Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
    2a8964d6
inode.c 154 KB