diff options
| -rw-r--r-- | drivers/block/ll_rw_blk.c | 17 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 17 |
2 files changed, 34 insertions, 0 deletions
diff --git a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c index e4db6ecf4faf..45d1b8ee1ce6 100644 --- a/drivers/block/ll_rw_blk.c +++ b/drivers/block/ll_rw_blk.c @@ -242,6 +242,7 @@ void blk_queue_make_request(request_queue_t * q, make_request_fn * mfn) q->backing_dev_info.state = 0; blk_queue_max_sectors(q, MAX_SECTORS); blk_queue_hardsect_size(q, 512); + blk_queue_dma_alignment(q, 511); /* * by default assume old behaviour and bounce for any highmem page @@ -408,6 +409,21 @@ void blk_queue_segment_boundary(request_queue_t *q, unsigned long mask) q->seg_boundary_mask = mask; } +/** + * blk_queue_dma_alignment - set dma length and memory alignment + * @q: the request queue for the device + * @dma_mask: alignment mask + * + * description: + * set required memory and length aligment for direct dma transactions. + * this is used when buiding direct io requests for the queue. + * + **/ +void blk_queue_dma_alignment(request_queue_t *q, int mask) +{ + q->dma_alignment = mask; +} + void blk_queue_assign_lock(request_queue_t *q, spinlock_t *lock) { spin_lock_init(lock); @@ -2124,6 +2140,7 @@ EXPORT_SYMBOL(blk_queue_max_hw_segments); EXPORT_SYMBOL(blk_queue_max_segment_size); EXPORT_SYMBOL(blk_queue_hardsect_size); EXPORT_SYMBOL(blk_queue_segment_boundary); +EXPORT_SYMBOL(blk_queue_dma_alignment); EXPORT_SYMBOL(blk_rq_map_sg); EXPORT_SYMBOL(blk_nohighio); EXPORT_SYMBOL(blk_dump_rq_flags); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 7ac2b3bb88e5..cd9b016a8993 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -215,6 +215,7 @@ struct request_queue unsigned int max_segment_size; unsigned long seg_boundary_mask; + unsigned int dma_alignment; wait_queue_head_t queue_wait; @@ -346,6 +347,7 @@ extern void blk_queue_segment_boundary(request_queue_t *, unsigned long); extern void blk_queue_assign_lock(request_queue_t *, spinlock_t *); extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn); extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *); +extern void blk_queue_dma_alignment(request_queue_t *, int); extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *); @@ -392,6 +394,21 @@ static inline int bdev_hardsect_size(struct block_device *bdev) return queue_hardsect_size(bdev_get_queue(bdev)); } +static inline int queue_dma_alignment(request_queue_t *q) +{ + int retval = 511; + + if (q && q->dma_alignment) + retval = q->dma_alignment; + + return retval; +} + +static inline int bdev_dma_aligment(struct block_device *bdev) +{ + return queue_dma_alignment(bdev_get_queue(bdev)); +} + #define blk_finished_io(nsects) do { } while (0) #define blk_started_io(nsects) do { } while (0) |