lkml.org 
[lkml]   [2007]   [Oct]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH -mm 09/11] call blk_queue_segment_boundary in __scsi_alloc_queue
    FUJITA Tomonori wrote:
    > On Wed, 24 Oct 2007 07:39:16 -0400
    > Jeff Garzik <jeff@garzik.org> wrote:
    >
    >> FUJITA Tomonori wrote:
    >>> request_queue and device struct must have the same value of a segment
    >>> size limit. This patch adds blk_queue_segment_boundary in
    >>> __scsi_alloc_queue so LLDs don't need to call both
    >>> blk_queue_segment_boundary and set_dma_max_seg_size. A LLD can change
    >>> the default value (64KB) can call device_dma_parameters accessors like
    >>> pci_set_dma_max_seg_size when allocating scsi_host.
    >>>
    >>> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
    >>> ---
    >>> drivers/scsi/scsi_lib.c | 3 +++
    >>> 1 files changed, 3 insertions(+), 0 deletions(-)
    >>>
    >>> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
    >>> index 61fdaf0..23a30ab 100644
    >>> --- a/drivers/scsi/scsi_lib.c
    >>> +++ b/drivers/scsi/scsi_lib.c
    >>> @@ -1645,6 +1645,7 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
    >>> request_fn_proc *request_fn)
    >>> {
    >>> struct request_queue *q;
    >>> + struct device *dev = shost->shost_gendev.parent;
    >>>
    >>> q = blk_init_queue(request_fn, NULL);
    >>> if (!q)
    >>> @@ -1673,6 +1674,8 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
    >>> blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost));
    >>> blk_queue_segment_boundary(q, shost->dma_boundary);
    >>>
    >>> + blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));
    >>> +
    >> it would be nice to have something more general that's useable in
    >> drivers/block/sx8.c (for example), something like
    >>
    >> static inline void
    >> dev_blk_associate(struct device *dev, request_queue *q)
    >> {
    >> blk_queue_max_segment_size(q,
    >> dma_get_max_seg_size(dev));
    >> }
    >>
    >> still, I will ACK the above patch (#9) in case you wish that to become a
    >> future cleanup, or others dislike this suggestion
    >
    > Yeah, I thought about something like that. But I can't find many
    > non-scsi drivers (ide, sx8, mmc/card/, anymore?) doing dma and having
    > the restrictions so I just call blk_queue_max_segment_size here.

    My main idea was that request_queue will eventually want to know struct
    device details directly, if it can.


    > Either is ok with me. I'll modify the patch if Jens prefers such
    > function. Jens?

    I have no strong opinion... it was just a thought.

    Jeff



    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-10-24 16:41    [W:0.028 / U:0.280 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site