Merge pull request #41529 from Yenya/rbd-deep-cp-docs

doc/rbd: document cp versus deep cp

Reviewed-by: Ilya Dryomov <idryomov@gmail.com>

doc/man/8/rbd.rst

@@ -237,6 +237,8 @@ Commands
 :command:`cp` (*src-image-spec* | *src-snap-spec*) *dest-image-spec*
   Copy the content of a src-image into the newly created dest-image.
   dest-image will have the same size, object size, and image format as src-image.
+  Note: snapshots are not copied, use `deep cp` command to include
+  snapshots.
 
 :command:`create` (-s | --size *size-in-M/G/T*) [--image-format *format-id*] [--object-size *size-in-B/K/M*] [--stripe-unit *size-in-B/K/M* --stripe-count *num*] [--thick-provision] [--no-progress] [--image-feature *feature-name*]... [--image-shared] *image-spec*
   Will create a new rbd image. You must also specify the size via --size.  The

src/test/cli/rbd/help.t

@@ -26,7 +26,8 @@
       config pool set                   Set a pool-level configuration override.
       copy (cp)                         Copy src image to dest.
       create                            Create an empty image.
-      deep copy (deep cp)               Deep copy src image to dest.
+      deep copy (deep cp)               Deep copy (including snapshots) src image
+                                        to dest.
       device attach                     Attach image to device.
       device detach                     Detach image from device.
       device list (showmapped)          List mapped rbd images.
@@ -533,7 +534,7 @@
                        [--no-progress] 
                        <source-image-or-snap-spec> <dest-image-spec> 
   
-  Deep copy src image to dest.
+  Deep copy (including snapshots) src image to dest.
   
   Positional arguments
     <source-image-or-snap-spec>  source image or snapshot specification

src/tools/rbd/action/Copy.cc

@@ -187,7 +187,7 @@ int execute_deep(const po::variables_map &vm,
 }
 
 Shell::Action action_deep(
-  {"deep", "copy"}, {"deep", "cp"}, "Deep copy src image to dest.",
+  {"deep", "copy"}, {"deep", "cp"}, "Deep copy (including snapshots) src image to dest.",
   at::get_long_features_help(), &get_arguments_deep, &execute_deep);
 
 } // namespace copy