From b65ed533d58a96f7cef4897b7ed2b6fcc940a734 Mon Sep 17 00:00:00 2001
From: Andy Grover <andy.grover@oracle.com>
Date: Mon, 13 Apr 2009 14:40:05 -0700
Subject: [PATCH] --- yaml --- r: 143213 b: refs/heads/master c:
 9de100d001564f58c3fb2ec1bd03e540ac0aa357 h: refs/heads/master i:   143211:
 79d7a6777ce1f70869b2495bebf7ecdf00906360 v: v3

---
 [refs]          |  2 +-
 trunk/mm/util.c | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 4eb03cfcf9cf..1b98e6e33358 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d20d5a7456d57d8affa88f45f27ae96ea49c29e4
+refs/heads/master: 9de100d001564f58c3fb2ec1bd03e540ac0aa357
diff --git a/trunk/mm/util.c b/trunk/mm/util.c
index 2599e83eea17..55bef160b9f1 100644
--- a/trunk/mm/util.c
+++ b/trunk/mm/util.c
@@ -223,6 +223,22 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
 }
 #endif
 
+/**
+ * get_user_pages_fast() - pin user pages in memory
+ * @start:	starting user address
+ * @nr_pages:	number of pages from start to pin
+ * @write:	whether pages will be written to
+ * @pages:	array that receives pointers to the pages pinned.
+ *		Should be at least nr_pages long.
+ *
+ * Attempt to pin user pages in memory without taking mm->mmap_sem.
+ * If not successful, it will fall back to taking the lock and
+ * calling get_user_pages().
+ *
+ * Returns number of pages pinned. This may be fewer than the number
+ * requested. If nr_pages is 0 or negative, returns 0. If no pages
+ * were pinned, returns -errno.
+ */
 int __attribute__((weak)) get_user_pages_fast(unsigned long start,
 				int nr_pages, int write, struct page **pages)
 {