[PATCH v4 20/23] block: set FOLL_PCI_P2PDMA in bio_map_user_iov()
From: Logan Gunthorpe <logang@deltatee.com>
Date: 2021-11-17 21:54:47
Also in:
linux-iommu, linux-mm, linux-nvme, linux-pci, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
When a bio's queue supports PCI P2PDMA, set FOLL_PCI_P2PDMA for iov_iter_get_pages_flags(). This allows PCI P2PDMA pages to be passed from userspace and enables the NVMe passthru requests to use P2PDMA pages. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> --- block/blk-map.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/block/blk-map.c b/block/blk-map.c
index 4526adde0156..7508448e290c 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c@@ -234,6 +234,7 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, gfp_t gfp_mask) { unsigned int max_sectors = queue_max_hw_sectors(rq->q); + unsigned int flags = 0; struct bio *bio; int ret; int j;
@@ -246,13 +247,17 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, return -ENOMEM; bio->bi_opf |= req_op(rq); + if (blk_queue_pci_p2pdma(rq->q)) + flags |= FOLL_PCI_P2PDMA; + while (iov_iter_count(iter)) { struct page **pages; ssize_t bytes; size_t offs, added = 0; int npages; - bytes = iov_iter_get_pages_alloc(iter, &pages, LONG_MAX, &offs); + bytes = iov_iter_get_pages_alloc_flags(iter, &pages, LONG_MAX, + &offs, flags); if (unlikely(bytes <= 0)) { ret = bytes ? bytes : -EFAULT; goto out_unmap;
--
2.30.2