Add lock_page_killable

This routine is like lock_page, but can be interrupted by a fatal signal

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index db8a410ae9e1..4b62a105622b 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -157,6 +157,7 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
 }
 
 extern void FASTCALL(__lock_page(struct page *page));
+extern int FASTCALL(__lock_page_killable(struct page *page));
 extern void FASTCALL(__lock_page_nosync(struct page *page));
 extern void FASTCALL(unlock_page(struct page *page));
 
@@ -171,6 +172,19 @@ static inline void lock_page(struct page *page)
 }
 
 /*
+ * lock_page_killable is like lock_page but can be interrupted by fatal
+ * signals.  It returns 0 if it locked the page and -EINTR if it was
+ * killed while waiting.
+ */
+static inline int lock_page_killable(struct page *page)
+{
+        might_sleep();
+        if (TestSetPageLocked(page))
+                return __lock_page_killable(page);
+        return 0;
+}
+
+/*
  * lock_page_nosync should only be used if we can't pin the page's inode.
  * Doesn't play quite so well with block device plugging.
  */