rbd: clarify "rbd {group,} rename" command description

Make it clearer that, despite a full image or group spec being taken
for source and destination, an image or a group can be renamed only
within its pool or namespace.

Rename across pools or namespaces within the same pool is unsupported.

Fixes: https://tracker.ceph.com/issues/67752
Signed-off-by: Ilya Dryomov <[email protected]>

Author: idryomov

src/test/cli/rbd/help.t

@@ -51,7 +51,8 @@
       group info                        Show information about a group.
       group list (group ls)             List rbd groups.
       group remove (group rm)           Delete a group.
-      group rename                      Rename a group within pool.
+      group rename                      Rename a group within its pool or
+                                        namespace.
       group snap create                 Make a snapshot of a group.
       group snap info                   Show information about a group snapshot.
       group snap list (... ls)          List snapshots of a group.
@@ -133,7 +134,8 @@
       pool init                         Initialize pool for use by RBD.
       pool stats                        Display pool statistics.
       remove (rm)                       Delete an image.
-      rename (mv)                       Rename image within pool.
+      rename (mv)                       Rename an image within its pool or
+                                        namespace.
       resize                            Resize (expand or shrink) image.
       snap create (snap add)            Create a snapshot.
       snap limit clear                  Remove snapshot limit.
@@ -1034,7 +1036,7 @@
                           [--dest-group <dest-group>] 
                           <source-group-spec> <dest-group-spec> 
 
-  Rename a group within pool.
+  Rename a group within its pool or namespace.
 
   Positional arguments
     <source-group-spec>  source group specification
@@ -2262,7 +2264,7 @@
                     [--dest-namespace <dest-namespace>] [--dest <dest>] 
                     <source-image-spec> <dest-image-spec> 
 
-  Rename image within pool.
+  Rename an image within its pool or namespace.
 
   Positional arguments
     <source-image-spec>  source image specification

src/tools/rbd/action/Group.cc

@@ -1046,7 +1046,7 @@ Shell::Action action_list(
   {"group", "list"}, {"group", "ls"}, "List rbd groups.",
   "", &get_list_arguments, &execute_list);
 Shell::Action action_rename(
-  {"group", "rename"}, {}, "Rename a group within pool.",
+  {"group", "rename"}, {}, "Rename a group within its pool or namespace.",
   "", &get_rename_arguments, &execute_rename);
 Shell::Action action_info(
   {"group", "info"}, {}, "Show information about a group.",

src/tools/rbd/action/Rename.cc

@@ -86,8 +86,8 @@ int execute(const po::variables_map &vm,
 }
 
 Shell::Action action(
-  {"rename"}, {"mv"}, "Rename image within pool.", "", &get_arguments,
-  &execute);
+  {"rename"}, {"mv"}, "Rename an image within its pool or namespace.", "",
+  &get_arguments, &execute);
 
 } // namespace rename
 } // namespace action