From: FUJITA Tomonori 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 Acked-by: Borislav Petkov Cc: Bartlomiej Zolnierkiewicz Cc: Thomas Bogendoerfer Cc: Tejun Heo Cc: Jens Axboe Cc: James Bottomley Signed-off-by: Andrew Morton --- drivers/ide/ide-cd.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff -puN drivers/ide/ide-cd.c~ide-use-the-dma-safe-check-for-req_type_ata_pc drivers/ide/ide-cd.c --- a/drivers/ide/ide-cd.c~ide-use-the-dma-safe-check-for-req_type_ata_pc +++ a/drivers/ide/ide-cd.c @@ -1191,10 +1191,15 @@ static ide_startstop_t cdrom_do_block_pc 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; @@ -1204,7 +1209,8 @@ static ide_startstop_t cdrom_do_block_pc * 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; } @@ -1872,6 +1878,7 @@ static int ide_cdrom_setup(ide_drive_t * 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; _