Thread (31 messages) 31 messages, 2 authors, 2019-12-17

[PATCH v10 15/25] fs/io_uring: set FOLL_PIN via pin_user_pages()

From: John Hubbard <jhubbard@nvidia.com>
Date: 2019-12-12 08:22:53
Also in: bpf, dri-devel, kvm, linux-doc, linux-fsdevel, linux-kselftest, linux-media, linux-mm, linux-rdma, linuxppc-dev, lkml, netdev
Subsystem: filesystems (vfs and infrastructure), the rest · Maintainers: Alexander Viro, Christian Brauner, Linus Torvalds

Convert fs/io_uring to use the new pin_user_pages() call, which sets
FOLL_PIN. Setting FOLL_PIN is now required for code that requires
tracking of pinned pages, and therefore for any code that calls
put_user_page().

In partial anticipation of this work, the io_uring code was already
calling put_user_page() instead of put_page(). Therefore, in order to
convert from the get_user_pages()/put_page() model, to the
pin_user_pages()/put_user_page() model, the only change required
here is to change get_user_pages() to pin_user_pages().

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
---
 fs/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 405be10da73d..9639ebc21e8a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4521,7 +4521,7 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg,
 
 		ret = 0;
 		down_read(&current->mm->mmap_sem);
-		pret = get_user_pages(ubuf, nr_pages,
+		pret = pin_user_pages(ubuf, nr_pages,
 				      FOLL_WRITE | FOLL_LONGTERM,
 				      pages, vmas);
 		if (pret == nr_pages) {
-- 
2.24.0
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help