aboutsummaryrefslogtreecommitdiffstats
path: root/mm/memory.c
diff options
context:
space:
mode:
authorJohannes Weiner <hannes@cmpxchg.org>2010-05-24 14:32:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-25 08:07:00 -0700
commit142762bd8d8c46345e79f0f68d3374564306972f (patch)
treec33360b872883d24b068ba7b8f01466fccb9dfc9 /mm/memory.c
parent58a9d3d8db06ca2ec31f64ec49ab0aeb89971b85 (diff)
downloadmrst-s0i3-test-142762bd8d8c46345e79f0f68d3374564306972f.tar.gz
mrst-s0i3-test-142762bd8d8c46345e79f0f68d3374564306972f.tar.xz
mrst-s0i3-test-142762bd8d8c46345e79f0f68d3374564306972f.zip
mm: document follow_page()
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Dan Carpenter <error27@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Izik Eidus <ieidus@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c13
1 files changed, 11 insertions, 2 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 833952d8b74..119b7ccdf39 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1227,8 +1227,17 @@ int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
}
EXPORT_SYMBOL_GPL(zap_vma_ptes);
-/*
- * Do a quick page-table lookup for a single page.
+/**
+ * follow_page - look up a page descriptor from a user-virtual address
+ * @vma: vm_area_struct mapping @address
+ * @address: virtual address to look up
+ * @flags: flags modifying lookup behaviour
+ *
+ * @flags can have FOLL_ flags set, defined in <linux/mm.h>
+ *
+ * Returns the mapped (struct page *), %NULL if no mapping exists, or
+ * an error pointer if there is a mapping to something not represented
+ * by a page descriptor (see also vm_normal_page()).
*/
struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
unsigned int flags)