splice: fix generic_file_splice_read() race with page invalidation

[linux-2.6-omap-h63xx.git] / fs / splice.c

diff --git a/fs/splice.c b/fs/splice.c
index aa5f6f60b3055f8a35b59084f0c652cb0e5c2125..399442179d89d5821b4caccc488fb0180e4e35c0 100644 (file)
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -379,13 +379,22 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
                                lock_page(page);
 
                        /*
-                        * page was truncated, stop here. if this isn't the
-                        * first page, we'll just complete what we already
-                        * added
+                        * Page was truncated, or invalidated by the
+                        * filesystem.  Redo the find/create, but this time the
+                        * page is kept locked, so there's no chance of another
+                        * race with truncate/invalidate.
                         */
                        if (!page->mapping) {
                                unlock_page(page);
-                               break;
+                               page = find_or_create_page(mapping, index,
+                                               mapping_gfp_mask(mapping));
+
+                               if (!page) {
+                                       error = -ENOMEM;
+                                       break;
+                               }
+                               page_cache_release(pages[page_nr]);
+                               pages[page_nr] = page;
                        }
                        /*
                         * page was already under io and is now done, great