• Amir Goldstein's avatar
    vfs: allow copy_file_range to copy across devices · 5dae222a
    Amir Goldstein authored
    We want to enable cross-filesystem copy_file_range functionality
    where possible, so push the "same superblock only" checks down to
    the individual filesystem callouts so they can make their own
    decisions about cross-superblock copy offload and fallack to
    generic_copy_file_range() for cross-superblock copy.
    
    [Amir] We do not call ->remap_file_range() in case the files are not
    on the same sb and do not call ->copy_file_range() in case the files
    do not belong to the same filesystem driver.
    
    This changes behavior of the copy_file_range(2) syscall, which will
    now allow cross filesystem in-kernel copy.  CIFS already supports
    cross-superblock copy, between two shares to the same server. This
    functionality will now be available via the copy_file_range(2) syscall.
    
    Cc: Steve French <stfrench@microsoft.com>
    Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
    Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
    Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
    Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
    5dae222a
read_write.c 50.7 KB