[PATCH] splice: fix unlocking of page on error ->prepare_write()
Looking at generic_file_buffered_write(), we need to unlock_page() if
prepare write fails and it isn't due to racing with truncate().
Also trim the size if ->prepare_write() fails, if we have to.
Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/fs/splice.c b/fs/splice.c
index 7fb0497..27f5e37 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -647,11 +647,24 @@
}
ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
- if (ret == AOP_TRUNCATED_PAGE) {
+ if (unlikely(ret)) {
+ loff_t isize = i_size_read(mapping->host);
+
+ if (ret != AOP_TRUNCATED_PAGE)
+ unlock_page(page);
page_cache_release(page);
- goto find_page;
- } else if (ret)
+ if (ret == AOP_TRUNCATED_PAGE)
+ goto find_page;
+
+ /*
+ * prepare_write() may have instantiated a few blocks
+ * outside i_size. Trim these off again.
+ */
+ if (sd->pos + this_len > isize)
+ vmtruncate(mapping->host, isize);
+
goto out;
+ }
if (buf->page != page) {
/*