[PATCHv3 3/7] blk-mq-dma: require unmap caller provide p2p map type
From: Keith Busch <hidden>
Date: 2025-07-29 14:35:03
Also in:
linux-nvme
Subsystem:
block layer, nvm express driver, the rest · Maintainers:
Jens Axboe, Keith Busch, Christoph Hellwig, Sagi Grimberg, Linus Torvalds
From: Keith Busch <kbusch@kernel.org> In preparing for integrity dma mappings, we can't rely on the request flag because data and metadata may have different mapping types. Signed-off-by: Keith Busch <kbusch@kernel.org> --- drivers/nvme/host/pci.c | 9 ++++++++- include/linux/blk-mq-dma.h | 5 +++-- 2 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 071efec25346f..6cefa8344f670 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c@@ -261,6 +261,9 @@ 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, }; struct nvme_dma_vec {
@@ -725,7 +728,8 @@ static void nvme_unmap_data(struct request *req) return; } - if (!blk_rq_dma_unmap(req, dma_dev, &iod->dma_state, iod->total_len)) { + if (!blk_rq_dma_unmap(req, dma_dev, &iod->dma_state, iod->total_len, + iod->flags & IOD_P2P_BUS_ADDR)) { if (nvme_pci_cmd_use_sgl(&iod->cmd)) nvme_free_sgls(req); else
@@ -1000,6 +1004,9 @@ 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)))
diff --git a/include/linux/blk-mq-dma.h b/include/linux/blk-mq-dma.h
index c82f880dee914..aef8d784952ff 100644
--- a/include/linux/blk-mq-dma.h
+++ b/include/linux/blk-mq-dma.h@@ -49,14 +49,15 @@ static inline bool blk_rq_dma_map_coalesce(struct dma_iova_state *state) * @dma_dev: device to unmap from * @state: DMA IOVA state * @mapped_len: number of bytes to unmap + * @is_p2p: true if mapped with PCI_P2PDMA_MAP_BUS_ADDR * * 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) + struct dma_iova_state *state, size_t mapped_len, bool is_p2p) { - if (req->cmd_flags & REQ_P2PDMA) + if (is_p2p) return true; if (dma_use_iova(state)) {
--
2.47.3