Commit d57447ff authored by Keith Busch's avatar Keith Busch Committed by Jens Axboe
Browse files

blk-mq-dma: bring back p2p request flags 



We only need to consider data and metadata dma mapping types separately.
The request and bio integrity payload have enough flag bits to
internally track the mapping type for each. Use these so the caller
doesn't need to track them, and provide separete request and integrity
helpers to the common code. This will make it easier to scale new
mappings, like the proposed MMIO attribute, without burdening the caller
to track such things.

Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 05ceea5d

block/blk-mq-dma.c

+4 −0
Original line number Diff line number Diff line
@@ -174,6 +174,10 @@ static bool blk_dma_map_iter_start(struct request *req, struct device *dma_dev, 
	switch (pci_p2pdma_state(&iter->p2pdma, dma_dev,

				 phys_to_page(vec.paddr))) {

	case PCI_P2PDMA_MAP_BUS_ADDR:

		if (iter->iter.is_integrity)

			bio_integrity(req->bio)->bip_flags |= BIP_P2P_DMA;

		else

			req->cmd_flags |= REQ_P2PDMA;

		return blk_dma_map_bus(iter, &vec);

	case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:

		/*

drivers/nvme/host/pci.c

+4 −17
Original line number Diff line number Diff line
@@ -260,12 +260,6 @@ enum nvme_iod_flags { 
	/* single segment dma mapping */

	IOD_SINGLE_SEGMENT	= 1U << 2,



	/* DMA mapped with PCI_P2PDMA_MAP_BUS_ADDR */

	IOD_P2P_BUS_ADDR	= 1U << 3,



	/* Metadata DMA mapped with PCI_P2PDMA_MAP_BUS_ADDR */

	IOD_META_P2P_BUS_ADDR	= 1U << 4,



	/* Metadata using non-coalesced MPTR */

	IOD_SINGLE_META_SEGMENT	= 1U << 5,

};
@@ -737,9 +731,8 @@ static void nvme_unmap_metadata(struct request *req) 
		return;

	}



	if (!blk_rq_dma_unmap(req, dma_dev, &iod->meta_dma_state,

				iod->meta_total_len,

				iod->flags & IOD_META_P2P_BUS_ADDR)) {

	if (!blk_rq_integrity_dma_unmap(req, dma_dev, &iod->meta_dma_state,

					iod->meta_total_len)) {

		if (nvme_pci_cmd_use_meta_sgl(&iod->cmd))

			nvme_free_sgls(req, sge, &sge[1]);

		else
@@ -766,8 +759,7 @@ static void nvme_unmap_data(struct request *req) 
		return;

	}



	if (!blk_rq_dma_unmap(req, dma_dev, &iod->dma_state, iod->total_len,

				iod->flags & IOD_P2P_BUS_ADDR)) {

	if (!blk_rq_dma_unmap(req, dma_dev, &iod->dma_state, iod->total_len)) {

		if (nvme_pci_cmd_use_sgl(&iod->cmd))

			nvme_free_sgls(req, iod->descriptors[0],

				       &iod->cmd.common.dptr.sgl);
@@ -1043,9 +1035,6 @@ static blk_status_t nvme_map_data(struct request *req) 
	if (!blk_rq_dma_map_iter_start(req, dev->dev, &iod->dma_state, &iter))

		return iter.status;



	if (iter.p2pdma.map == PCI_P2PDMA_MAP_BUS_ADDR)

		iod->flags |= IOD_P2P_BUS_ADDR;



	if (use_sgl == SGL_FORCED ||

	    (use_sgl == SGL_SUPPORTED &&

	     (sgl_threshold && nvme_pci_avg_seg_size(req) >= sgl_threshold)))
@@ -1068,9 +1057,7 @@ static blk_status_t nvme_pci_setup_meta_sgls(struct request *req) 
						&iod->meta_dma_state, &iter))

		return iter.status;



	if (iter.p2pdma.map == PCI_P2PDMA_MAP_BUS_ADDR)

		iod->flags |= IOD_META_P2P_BUS_ADDR;

	else if (blk_rq_dma_map_coalesce(&iod->meta_dma_state))

	if (blk_rq_dma_map_coalesce(&iod->meta_dma_state))

		entries = 1;



	/*

include/linux/bio-integrity.h

+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ enum bip_flags { 
	BIP_CHECK_GUARD		= 1 << 5, /* guard check */

	BIP_CHECK_REFTAG	= 1 << 6, /* reftag check */

	BIP_CHECK_APPTAG	= 1 << 7, /* apptag check */

	BIP_P2P_DMA		= 1 << 8, /* using P2P address */

};



struct bio_integrity_payload {

include/linux/blk-integrity.h

+15 −0
Original line number Diff line number Diff line
@@ -27,6 +27,15 @@ static inline bool queue_limits_stack_integrity_bdev(struct queue_limits *t, 


#ifdef CONFIG_BLK_DEV_INTEGRITY

int blk_rq_map_integrity_sg(struct request *, struct scatterlist *);



static inline bool blk_rq_integrity_dma_unmap(struct request *req,

		struct device *dma_dev, struct dma_iova_state *state,

		size_t mapped_len)

{

	return blk_dma_unmap(req, dma_dev, state, mapped_len,

			bio_integrity(req->bio)->bip_flags & BIP_P2P_DMA);

}



int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);

int blk_rq_integrity_map_user(struct request *rq, void __user *ubuf,

			      ssize_t bytes);
@@ -115,6 +124,12 @@ static inline int blk_rq_map_integrity_sg(struct request *q, 
{

	return 0;

}

static inline bool blk_rq_integrity_dma_unmap(struct request *req,

		struct device *dma_dev, struct dma_iova_state *state,

		size_t mapped_len)

{

	return false;

}

static inline int blk_rq_integrity_map_user(struct request *rq,

					    void __user *ubuf,

					    ssize_t bytes)

include/linux/blk-mq-dma.h

+9 −2
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ static inline bool blk_rq_dma_map_coalesce(struct dma_iova_state *state) 
}



/**

 * blk_rq_dma_unmap - try to DMA unmap a request

 * blk_dma_unmap - try to DMA unmap a request

 * @req:	request to unmap

 * @dma_dev:	device to unmap from

 * @state:	DMA IOVA state
@@ -53,7 +53,7 @@ static inline bool blk_rq_dma_map_coalesce(struct dma_iova_state *state) 
 * Returns %false if the callers need to manually unmap every DMA segment

 * mapped using @iter or %true if no work is left to be done.

 */

static inline bool blk_rq_dma_unmap(struct request *req, struct device *dma_dev,

static inline bool blk_dma_unmap(struct request *req, struct device *dma_dev,

		struct dma_iova_state *state, size_t mapped_len, bool is_p2p)

{

	if (is_p2p)
@@ -68,4 +68,11 @@ static inline bool blk_rq_dma_unmap(struct request *req, struct device *dma_dev, 
	return !dma_need_unmap(dma_dev);

}



static inline bool blk_rq_dma_unmap(struct request *req, struct device *dma_dev,

		struct dma_iova_state *state, size_t mapped_len)

{

	return blk_dma_unmap(req, dma_dev, state, mapped_len,

				req->cmd_flags & REQ_P2PDMA);

}



#endif /* BLK_MQ_DMA_H */