Re: [PATCH 3/4] ide: use the dma safe check for REQ_TYPE_ATA_PC

Borislav Petkov
2008-05-28T06:43:00Z

On Tue, May 20, 2008 at 01:58:33PM +0900, FUJITA Tomonori wrote:
> This uses the dma safe check for REQ_TYPE_ATA_PC. The dma safe check
> is used for only sg requests but it should be used for other non fs
> commands.
>
> This uses blk_queue_update_dma_pad to make the intention clear though
> ide don't use the blk APIs so it doesn't change anything.
>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> ---
> drivers/ide/ide-cd.c | 17 ++++++++++++-----
> 1 files changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
> index 68e7f19..1d8d510 100644
> --- a/drivers/ide/ide-cd.c
> +++ b/drivers/ide/ide-cd.c
> @@ -1178,10 +1178,15 @@ static ide_startstop_t cdrom_do_block_pc(ide_drive_t *drive, struct request *rq)
> info->dma = 0;
>
> /* sg request */
> - if (rq->bio) {
> - int mask = drive->queue->dma_alignment;
> - unsigned long addr =
> - (unsigned long)page_address(bio_page(rq->bio));
> + if (rq->bio || ((rq->cmd_type == REQ_TYPE_ATA_PC) && rq->data_len)) {
> + struct request_queue *q = drive->queue;
> + unsigned int alignment;
> + unsigned long addr;
> +
> + if (rq->bio)
> + addr = (unsigned long)bio_data(rq->bio);
> + else
> + addr = (unsigned long)rq->data;
>
> info->dma = drive->using_dma;
>
> @@ -1191,7 +1196,8 @@ static ide_startstop_t cdrom_do_block_pc(ide_drive_t *drive, struct request *rq)
> * NOTE! The "len" and "addr" checks should possibly have
> * separate masks.
> */
> - if ((rq->data_len & 15) || (addr & mask))
> + alignment = queue_dma_alignment(q) | q->dma_pad_mask;
> + if (addr & alignment || rq->data_len & alignment)
> info->dma = 0;
> }
>
> @@ -1869,6 +1875,7 @@ static int ide_cdrom_setup(ide_drive_t *drive)
>
> blk_queue_prep_rq(drive->queue, ide_cdrom_prep_fn);
> blk_queue_dma_alignment(drive->queue, 31);
> + blk_queue_update_dma_pad(drive->queue, 15);
> drive->queue->unplug_delay = (1 * HZ) / 1000;
> if (!drive->queue->unplug_delay)
> drive->queue->unplug_delay = 1;

Looks good to me.

Acked-by: Borislav Petkov <petkovbb@gmail.com>
--
Regards/Gruß,
Boris.