HWPOISON: Export some rmap vma locking to outside world
Needed for later patch that walks rmap entries on its own.
This used to be very frowned upon, but memory-failure.c does
some rather specialized rmap walking and rmap has been stable
for quite some time, so I think it's ok now to export it.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index bf116d0..8dff2ff 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -112,6 +112,12 @@
*/
int try_to_munlock(struct page *);
+/*
+ * Called by memory-failure.c to kill processes.
+ */
+struct anon_vma *page_lock_anon_vma(struct page *page);
+void page_unlock_anon_vma(struct anon_vma *anon_vma);
+
#else /* !CONFIG_MMU */
#define anon_vma_init() do {} while (0)
diff --git a/mm/rmap.c b/mm/rmap.c
index 0895b5c..5a35c03 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -191,7 +191,7 @@
* Getting a lock on a stable anon_vma from a page off the LRU is
* tricky: page_lock_anon_vma rely on RCU to guard against the races.
*/
-static struct anon_vma *page_lock_anon_vma(struct page *page)
+struct anon_vma *page_lock_anon_vma(struct page *page)
{
struct anon_vma *anon_vma;
unsigned long anon_mapping;
@@ -211,7 +211,7 @@
return NULL;
}
-static void page_unlock_anon_vma(struct anon_vma *anon_vma)
+void page_unlock_anon_vma(struct anon_vma *anon_vma)
{
spin_unlock(&anon_vma->lock);
rcu_read_unlock();