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block: set FOLL_PCI_P2PDMA in bio_map_user_iov() 

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>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-8-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Logan Gunthorpe 2022-10-21 11:41:14 -06:00 committed by Jens Axboe
parent 5e3e3f2e15
commit 7ee4ccf574
1 changed files with 8 additions and 4 deletions
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12
block/blk-map.c
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@ -267,6 +267,7 @@ 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;
@ -278,6 +279,9 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
if (bio == NULL)
return -ENOMEM;
if (blk_queue_pci_p2pdma(rq->q))
gup_flags |= FOLL_PCI_P2PDMA;
while (iov_iter_count(iter)) {
struct page **pages, *stack_pages[UIO_FASTIOV];
ssize_t bytes;
@ -286,11 +290,11 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
if (nr_vecs <= ARRAY_SIZE(stack_pages)) {
pages = stack_pages;
bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
nr_vecs, &offs);
bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
nr_vecs, &offs, gup_flags);
} else {
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;