gfs2: don't allow releasepage to free bd still used for revokes
Before this patch, function gfs2_releasepage would free any bd
elements that had been used for the page being released. However,
those bd elements may still be queued to the sd_log_revokes list,
in which case we cannot free them until the revoke has been issued.
This patch adds additional checks for bds that are still being
used for revokes.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index ba83b49..786c1ce 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -805,11 +805,16 @@ int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
bd = bh->b_private;
if (bd) {
gfs2_assert_warn(sdp, bd->bd_bh == bh);
- if (!list_empty(&bd->bd_list))
- list_del_init(&bd->bd_list);
bd->bd_bh = NULL;
bh->b_private = NULL;
- kmem_cache_free(gfs2_bufdata_cachep, bd);
+ /*
+ * The bd may still be queued as a revoke, in which
+ * case we must not dequeue nor free it.
+ */
+ if (!bd->bd_blkno && !list_empty(&bd->bd_list))
+ list_del_init(&bd->bd_list);
+ if (list_empty(&bd->bd_list))
+ kmem_cache_free(gfs2_bufdata_cachep, bd);
}
bh = bh->b_this_page;