[PATCH] vmsplice: fix badly placed end paranthesis

We need to use the minium of {len, PAGE_SIZE-off}, not {len, PAGE_SIZE}-off.
The latter doesn't make any sense, and could cause us to attempt negative
length transfers...

Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/fs/splice.c b/fs/splice.c
index b150493..b0c157d 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1143,7 +1143,7 @@
 		 * Fill this contiguous range into the partial page map.
 		 */
 		for (i = 0; i < error; i++) {
-			const int plen = min_t(size_t, len, PAGE_SIZE) - off;
+			const int plen = min_t(size_t, len, PAGE_SIZE - off);
 
 			partial[buffers].offset = off;
 			partial[buffers].len = plen;