rbd: make ceph_parse_options() return a pointer

ceph_parse_options() takes the address of a pointer as an argument
and uses it to return the address of an allocated structure if
successful.  With this interface is not evident at call sites that
the pointer is always initialized.  Change the interface to return
the address instead (or a pointer-coded error code) to make the
validity of the returned pointer obvious.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index b9371f0b9532..ed6711e35323 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -371,11 +371,13 @@ static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr,
 
         rbd_opts->notify_timeout = RBD_NOTIFY_TIMEOUT_DEFAULT;
 
-        ret = ceph_parse_options(&opt, options, mon_addr,
+        opt = ceph_parse_options(options, mon_addr,
                                 mon_addr + strlen(mon_addr),
                                 parse_rbd_opts_token, rbd_opts);
-        if (ret < 0)
+        if (IS_ERR(opt)) {
+                ret = PTR_ERR(opt);
                 goto done_err;
+        }
 
         spin_lock(&node_lock);
         rbdc = __rbd_client_find(opt);