From: Dmitriy Monakhov <dmonakhov@sw.ru>
Date: Thu, 29 Mar 2007 12:24:09 +0000 (+0200)
Subject: [PATCH] splice: partial write fix
X-Git-Tag: v3.12-rc1~30860^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d9993c37ef87c758d4a6e63972395b1cf8a4cb7b;p=kernel%2Fkernel-generic.git

[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
--- 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);