• Tao Ma's avatar
    xfs: Make fiemap work in query mode. · 2d1ff3c7
    Tao Ma authored
    According to Documentation/filesystems/fiemap.txt, If fm_extent_count
    is zero, then the fm_extents[] array is ignored (no extents will be
    returned), and the fm_mapped_extents count will hold the number of
    extents needed.
    
    But as the commit 97db39a1 has changed
    bmv_count to the caller's input buffer, this number query function can't
    work any more. As this commit is written to change bmv_count from
    MAXEXTNUM because of ENOMEM.
    
    This patch just try to  set bm.bmv_count to something sane.
    Thanks to Dave Chinner <david@fromorbit.com> for the suggestion.
    
    Cc: Eric Sandeen <sandeen@redhat.com>
    Cc: Alex Elder <aelder@sgi.com>
    Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
    Signed-off-by: default avatarTao Ma <tao.ma@oracle.com>
    2d1ff3c7
xfs_iops.c 19.7 KB