Vmscan: Save irqflags on taking the mapping lock

Signed-off-by: Christoph Lameter <clameter@sgi.com>

---
 mm/vmscan.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Index: linux-2.6/mm/vmscan.c
===================================================================
--- linux-2.6.orig/mm/vmscan.c	2007-08-13 22:47:14.000000000 -0700
+++ linux-2.6/mm/vmscan.c	2007-08-13 22:47:52.000000000 -0700
@@ -377,10 +377,12 @@ static pageout_t pageout(struct page *pa
  */
 int remove_mapping(struct address_space *mapping, struct page *page)
 {
+	unsigned long flags;
+
 	BUG_ON(!PageLocked(page));
 	BUG_ON(mapping != page_mapping(page));
 
-	write_lock_irq(&mapping->tree_lock);
+	write_lock_irqsave(&mapping->tree_lock, flags);
 	/*
 	 * The non racy check for a busy page.
 	 *
@@ -415,19 +417,19 @@ int remove_mapping(struct address_space 
 	if (PageSwapCache(page)) {
 		swp_entry_t swap = { .val = page_private(page) };
 		__delete_from_swap_cache(page);
-		write_unlock_irq(&mapping->tree_lock);
+		write_unlock_irqrestore(&mapping->tree_lock, flags);
 		swap_free(swap);
 		__put_page(page);	/* The pagecache ref */
 		return 1;
 	}
 
 	__remove_from_page_cache(page);
-	write_unlock_irq(&mapping->tree_lock);
+	write_unlock_irqrestore(&mapping->tree_lock, flags);
 	__put_page(page);
 	return 1;
 
 cannot_free:
-	write_unlock_irq(&mapping->tree_lock);
+	write_unlock_irqrestore(&mapping->tree_lock, flags);
 	return 0;
 }