[GFS2] Unlock page on prepare_write try lock failure

When the try lock of the glock failed in prepare_write we were
incorrectly exiting this function with the page still locked.
This was resulting in further I/O to this page hanging.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 9ddf9753a55..5e9653c4d88 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -360,8 +360,10 @@ static int gfs2_prepare_write(struct file *file, struct page *page,
         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
         error = gfs2_glock_nq_atime(&ip->i_gh);
         if (unlikely(error)) {
-                if (error == GLR_TRYFAILED)
+                if (error == GLR_TRYFAILED) {
+                        unlock_page(page);
                         error = AOP_TRUNCATED_PAGE;
+                }
                 goto out_uninit;
         }