ceph: properly release page upon error

When ceph_update_writeable_page fails (including -EAGAIN), it
unlocks (w/ unlock_page) the page but does not 'release'
(w/ page_cache_release) properly.

Upon error, properly set *pagep to NULL, indicating an error.

Signed-off-by: Taesoo Kim <tsgatesv@gmail.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index fd5599d32362..e723482c5f37 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1146,6 +1146,10 @@ static int ceph_write_begin(struct file *file, struct address_space *mapping,
                      inode, page, (int)pos, (int)len);
 
                 r = ceph_update_writeable_page(file, pos, len, page);
+                if (r < 0)
+                        page_cache_release(page);
+                else
+                        *pagep = page;
         } while (r == -EAGAIN);
 
         return r;