• Julian Wiedmann's avatar
    s390/qdio: allow for non-contiguous SBAL array in init_data · d8564e19
    Julian Wiedmann authored
    Upper-layer drivers allocate their SBALs by calling qdio_alloc_buffers()
    for each individual queue. But when later passing the SBAL addresses to
    qdio_establish(), they need to be in a single array of pointers.
    So if the driver uses multiple Input or Output queues, it needs to
    allocate a temporary array just to present all its SBAL pointers in this
    layout.
    
    This patch slightly changes the format of the QDIO initialization data,
    so that drivers can pass a per-queue array where each element points to
    a queue's SBAL array.
    zfcp doesn't use multiple queues, so the impact there is trivial.
    For qeth this brings a nice reduction in complexity, and removes
    a page-sized allocation.
    Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
    Reviewed-by: default avatarBenjamin Block <bblock@linux.ibm.com>
    Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
    d8564e19
qdio.h 12 KB