summaryrefslogtreecommitdiff
path: root/mm/gup.c
diff options
context:
space:
mode:
authorJohn Hubbard <jhubbard@nvidia.com>2020-06-01 21:48:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-02 10:59:08 -0700
commit91429023342789a89f4b6ae95b47a7df71ab6d95 (patch)
treeb63170a8b725f0d602bfd9be1035480427f77829 /mm/gup.c
parentadc8cb406e52f89071f488848b0fb3e7907ae332 (diff)
mm/gup: introduce pin_user_pages_unlocked
Introduce pin_user_pages_unlocked(), which is nearly identical to the get_user_pages_unlocked() that it wraps, except that it sets FOLL_PIN and rejects FOLL_GET. Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Walls <awalls@md.metrocast.net> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Link: http://lkml.kernel.org/r/20200518012157.1178336-2-jhubbard@nvidia.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/gup.c')
-rw-r--r--mm/gup.c17
1 files changed, 17 insertions, 0 deletions
diff --git a/mm/gup.c b/mm/gup.c
index ca723a33268e..c3014669988b 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2960,3 +2960,20 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages,
pages, vmas, gup_flags);
}
EXPORT_SYMBOL(pin_user_pages);
+
+/*
+ * pin_user_pages_unlocked() is the FOLL_PIN variant of
+ * get_user_pages_unlocked(). Behavior is the same, except that this one sets
+ * FOLL_PIN and rejects FOLL_GET.
+ */
+long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
+ struct page **pages, unsigned int gup_flags)
+{
+ /* FOLL_GET and FOLL_PIN are mutually exclusive. */
+ if (WARN_ON_ONCE(gup_flags & FOLL_GET))
+ return -EINVAL;
+
+ gup_flags |= FOLL_PIN;
+ return get_user_pages_unlocked(start, nr_pages, pages, gup_flags);
+}
+EXPORT_SYMBOL(pin_user_pages_unlocked);