[PATCH] page invalidation cleanup
Clean up the invalidate code, and use a common function to safely remove
the page from pagecache.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/truncate.c b/mm/truncate.c
index c6ab55e..a654928 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -9,6 +9,7 @@
#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/swap.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/pagevec.h>
@@ -52,36 +53,26 @@
/*
* This is for invalidate_inode_pages(). That function can be called at
* any time, and is not supposed to throw away dirty pages. But pages can
- * be marked dirty at any time too. So we re-check the dirtiness inside
- * ->tree_lock. That provides exclusion against the __set_page_dirty
- * functions.
+ * be marked dirty at any time too, so use remove_mapping which safely
+ * discards clean, unused pages.
*
* Returns non-zero if the page was successfully invalidated.
*/
static int
invalidate_complete_page(struct address_space *mapping, struct page *page)
{
+ int ret;
+
if (page->mapping != mapping)
return 0;
if (PagePrivate(page) && !try_to_release_page(page, 0))
return 0;
- write_lock_irq(&mapping->tree_lock);
- if (PageDirty(page))
- goto failed;
- if (page_count(page) != 2) /* caller's ref + pagecache ref */
- goto failed;
-
- BUG_ON(PagePrivate(page));
- __remove_from_page_cache(page);
- write_unlock_irq(&mapping->tree_lock);
+ ret = remove_mapping(mapping, page);
ClearPageUptodate(page);
- page_cache_release(page); /* pagecache ref */
- return 1;
-failed:
- write_unlock_irq(&mapping->tree_lock);
- return 0;
+
+ return ret;
}
/**