Commit e2be2ba6 authored by Keith Busch's avatar Keith Busch Committed by Jens Axboe
Browse files

blk-mq-dma: move common dma start code to a helper 



In preparing for dma mapping integrity metadata, move the common dma
setup to a helper.

Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
Reviewed-by: default avatarKanchan Joshi <joshi.k@samsung.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-6-kbusch@meta.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 70926390

block/blk-mq-dma.c

+33 −26
Original line number Diff line number Diff line
@@ -141,35 +141,12 @@ static inline void blk_rq_map_iter_init(struct request *rq, 
	}

}



/**

 * blk_rq_dma_map_iter_start - map the first DMA segment for a request

 * @req:	request to map

 * @dma_dev:	device to map to

 * @state:	DMA IOVA state

 * @iter:	block layer DMA iterator

 *

 * Start DMA mapping @req to @dma_dev.  @state and @iter are provided by the

 * caller and don't need to be initialized.  @state needs to be stored for use

 * at unmap time, @iter is only needed at map time.

 *

 * Returns %false if there is no segment to map, including due to an error, or

 * %true ft it did map a segment.

 *

 * If a segment was mapped, the DMA address for it is returned in @iter.addr and

 * the length in @iter.len.  If no segment was mapped the status code is

 * returned in @iter.status.

 *

 * The caller can call blk_rq_dma_map_coalesce() to check if further segments

 * need to be mapped after this, or go straight to blk_rq_dma_map_iter_next()

 * to try to map the following segments.

 */

bool blk_rq_dma_map_iter_start(struct request *req, struct device *dma_dev,

		struct dma_iova_state *state, struct blk_dma_iter *iter)

static bool blk_dma_map_iter_start(struct request *req, struct device *dma_dev,

		struct dma_iova_state *state, struct blk_dma_iter *iter,

		unsigned int total_len)

{

	unsigned int total_len = blk_rq_payload_bytes(req);

	struct phys_vec vec;



	blk_rq_map_iter_init(req, &iter->iter);

	memset(&iter->p2pdma, 0, sizeof(iter->p2pdma));

	iter->status = BLK_STS_OK;
@@ -201,6 +178,36 @@ bool blk_rq_dma_map_iter_start(struct request *req, struct device *dma_dev, 
		return blk_rq_dma_map_iova(req, dma_dev, state, iter, &vec);

	return blk_dma_map_direct(req, dma_dev, iter, &vec);

}



/**

 * blk_rq_dma_map_iter_start - map the first DMA segment for a request

 * @req:	request to map

 * @dma_dev:	device to map to

 * @state:	DMA IOVA state

 * @iter:	block layer DMA iterator

 *

 * Start DMA mapping @req to @dma_dev.  @state and @iter are provided by the

 * caller and don't need to be initialized.  @state needs to be stored for use

 * at unmap time, @iter is only needed at map time.

 *

 * Returns %false if there is no segment to map, including due to an error, or

 * %true ft it did map a segment.

 *

 * If a segment was mapped, the DMA address for it is returned in @iter.addr and

 * the length in @iter.len.  If no segment was mapped the status code is

 * returned in @iter.status.

 *

 * The caller can call blk_rq_dma_map_coalesce() to check if further segments

 * need to be mapped after this, or go straight to blk_rq_dma_map_iter_next()

 * to try to map the following segments.

 */

bool blk_rq_dma_map_iter_start(struct request *req, struct device *dma_dev,

		struct dma_iova_state *state, struct blk_dma_iter *iter)

{

	blk_rq_map_iter_init(req, &iter->iter);

	return blk_dma_map_iter_start(req, dma_dev, state, iter,

				      blk_rq_payload_bytes(req));

}

EXPORT_SYMBOL_GPL(blk_rq_dma_map_iter_start);



/**