[PATCH] splice: partial write fix

Currently if partial write has happened while ->commit_write() then page
wasn't marked as accessed and rebalanced.

Signed-off-by: Monakhov Dmitriy <dmonakhov@openvz.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/fs/splice.c b/fs/splice.c
index 07f6556..5428b0f 100644 (file)
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -627,18 +627,25 @@ find_page:
        }
 
        ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);
-       if (!ret) {
+       if (ret) {
+               if (ret == AOP_TRUNCATED_PAGE) {
+                       page_cache_release(page);
+                       goto find_page;
+               }
+               if (ret < 0)
+                       goto out;
                /*
-                * Return the number of bytes written and mark page as
-                * accessed, we are now done!
+                * Partial write has happened, so 'ret' already initialized by
+                * number of bytes written, Where is nothing we have to do here.
                 */
+       } else
                ret = this_len;
-               mark_page_accessed(page);
-               balance_dirty_pages_ratelimited(mapping);
-       } else if (ret == AOP_TRUNCATED_PAGE) {
-               page_cache_release(page);
-               goto find_page;
-       }
+       /*
+        * Return the number of bytes written and mark page as
+        * accessed, we are now done!
+        */
+       mark_page_accessed(page);
+       balance_dirty_pages_ratelimited(mapping);
 out:
        page_cache_release(page);
        unlock_page(page);