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/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef BLK_MQ_DMA_H
#define BLK_MQ_DMA_H
#include <linux/blk-mq.h>
#include <linux/pci-p2pdma.h>
struct blk_dma_iter {
/* Output address range for this iteration */
dma_addr_t addr;
u32 len;
/* Status code. Only valid when blk_rq_dma_map_iter_* returned false */
blk_status_t status;
/* Internal to blk_rq_dma_map_iter_* */
struct req_iterator iter;
struct pci_p2pdma_map_state p2pdma;
};
bool blk_rq_dma_map_iter_start(struct request *req, struct device *dma_dev,
struct dma_iova_state *state, struct blk_dma_iter *iter);
bool blk_rq_dma_map_iter_next(struct request *req, struct device *dma_dev,
struct dma_iova_state *state, struct blk_dma_iter *iter);
/**
* blk_rq_dma_map_coalesce - were all segments coalesced?
* @state: DMA state to check
*
* Returns true if blk_rq_dma_map_iter_start coalesced all segments into a
* single DMA range.
*/
static inline bool blk_rq_dma_map_coalesce(struct dma_iova_state *state)
{
return dma_use_iova(state);
}
/**
* blk_rq_dma_unmap - try to DMA unmap a request
* @req: request to unmap
* @dma_dev: device to unmap from
* @state: DMA IOVA state
* @mapped_len: number of bytes to unmap
*
* 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,
struct dma_iova_state *state, size_t mapped_len)
{
if (req->cmd_flags & REQ_P2PDMA)
return true;
if (dma_use_iova(state)) {
dma_iova_destroy(dma_dev, state, mapped_len, rq_dma_dir(req),
0);
return true;
}
return !dma_need_unmap(dma_dev);
}
#endif /* BLK_MQ_DMA_H */
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