diff options
| author |   John Hubbard <jhubbard@nvidia.com> | 2020-06-07 21:41:05 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-08 11:05:56 -0700 |
| commit | 55a650c35fea7cfdf989647f37960dfaf76da737 (patch) | |
| tree | ab120161257378582720cc684488499c22fe32c7 /mm | |
| parent | mm/gup: introduce pin_user_pages_locked() (diff) | |
| download | linux-dev-55a650c35fea7cfdf989647f37960dfaf76da737.tar.xz linux-dev-55a650c35fea7cfdf989647f37960dfaf76da737.zip | |
mm/gup: frame_vector: convert get_user_pages() --> pin_user_pages()
This code was using get_user_pages*(), and all of the callers so far
were in a "Case 2" scenario (DMA/RDMA), using the categorization from [1].
That means that it's time to convert the get_user_pages*() + put_page()
calls to pin_user_pages*() + unpin_user_pages() calls.
There is some helpful background in [2]: basically, this is a small part
of fixing a long-standing disconnect between pinning pages, and file
systems' use of those pages.
[1] Documentation/core-api/pin_user_pages.rst
[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Link: http://lkml.kernel.org/r/20200527223243.884385-3-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/frame_vector.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/mm/frame_vector.c b/mm/frame_vector.c index c431ca81dad5..4107dbca0056 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c @@ -72,7 +72,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) { vec->got_ref = true; vec->is_pfns = false; - ret = get_user_pages_locked(start, nr_frames, + ret = pin_user_pages_locked(start, nr_frames, gup_flags, (struct page **)(vec->ptrs), &locked); goto out; } @@ -122,7 +122,6 @@ EXPORT_SYMBOL(get_vaddr_frames); */ void put_vaddr_frames(struct frame_vector *vec) { - int i; struct page **pages; if (!vec->got_ref) @@ -135,8 +134,8 @@ void put_vaddr_frames(struct frame_vector *vec) */ if (WARN_ON(IS_ERR(pages))) goto out; - for (i = 0; i < vec->nr_frames; i++) - put_page(pages[i]); + + unpin_user_pages(pages, vec->nr_frames); vec->got_ref = false; out: vec->nr_frames = 0; |