X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ftruncate.c;h=cf1b015df4a7d770d3bccdecb9b8cef62de529d0;hb=60d48f1e23c25d09dbe7025ff179b808d72704b3;hp=b1a463d0fe713dbf671a7fa4a8e439e138ee56fa;hpb=5367f2d67c7d0bf1faae90e6e7b4e2ac3c9b5e0f;p=linux-2.6

diff --git a/mm/truncate.c b/mm/truncate.c
index b1a463d0fe..cf1b015df4 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -196,7 +196,7 @@ EXPORT_SYMBOL(truncate_inode_pages_range);
  * @mapping: mapping to truncate
  * @lstart: offset from which to truncate
  *
- * Called under (and serialised by) inode->i_sem.
+ * Called under (and serialised by) inode->i_mutex.
  */
 void truncate_inode_pages(struct address_space *mapping, loff_t lstart)
 {
@@ -230,14 +230,24 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping,
 			pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
 		for (i = 0; i < pagevec_count(&pvec); i++) {
 			struct page *page = pvec.pages[i];
+			pgoff_t index;
+			int lock_failed;
 
-			if (TestSetPageLocked(page)) {
-				next++;
-				continue;
-			}
-			if (page->index > next)
-				next = page->index;
+			lock_failed = TestSetPageLocked(page);
+
+			/*
+			 * We really shouldn't be looking at the ->index of an
+			 * unlocked page.  But we're not allowed to lock these
+			 * pages.  So we rely upon nobody altering the ->index
+			 * of this (pinned-by-us) page.
+			 */
+			index = page->index;
+			if (index > next)
+				next = index;
 			next++;
+			if (lock_failed)
+				continue;
+
 			if (PageDirty(page) || PageWriteback(page))
 				goto unlock;
 			if (page_mapped(page))