[PATCH v10 6/8] block: set FOLL_PCI_P2PDMA in bio_map_user_iov()

[Logan Gunthorpe]

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@xxxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
---
 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 7196a6b64c80..7882504b99ac 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -236,6 +236,7 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
 {
 	unsigned int max_sectors = queue_max_hw_sectors(rq->q);
 	unsigned int nr_vecs = iov_iter_npages(iter, BIO_MAX_VECS);
+	unsigned int gup_flags = 0;
 	struct bio *bio;
 	int ret;
 	int j;
@@ -248,13 +249,17 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
 		return -ENOMEM;
 	bio_init(bio, NULL, bio->bi_inline_vecs, nr_vecs, req_op(rq));
 
+	if (blk_queue_pci_p2pdma(rq->q))
+		gup_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_alloc2(iter, &pages, LONG_MAX, &offs);
+		bytes = iov_iter_get_pages_alloc(iter, &pages, LONG_MAX,
+						 &offs, gup_flags);
 		if (unlikely(bytes <= 0)) {
 			ret = bytes ? bytes : -EFAULT;
 			goto out_unmap;
-- 
2.30.2