On container rm, don't remove named mountpoints

This makes it so when calling `docker run --rm`, or `docker rm -v`, only
volumes specified without a name, e.g. `docker run -v /foo` instead of
`docker run -v awesome:/foo` are removed.

Note that all volumes are named, some are named by the user, some get a
generated name. This is specifically about how the volume was specified
on `run`, assuming that if the user specified it with a name they expect
it to persist after the container is cleaned up.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>

docs/reference/commandline/rm.md

@@ -45,3 +45,17 @@ This command will delete all stopped containers. The command
 `docker ps -a -q` will return all existing container IDs and pass them to
 the `rm` command which will delete them. Any running containers will not be
 deleted.
+
+  $ docker rm -v redis
+  redis
+
+This command will remove the container and any volumes associated with it.
+Note that if a volume was specified with a name, it will not be removed.
+
+  $ docker create -v awesome:/foo -v /bar --name hello redis
+  hello
+  $ docker rm -v hello
+
+In this example, the volume for `/foo` will remain intact, but the volume for
+`/bar` will be removed. The same behavior holds for volumes inherited with
+`--volumes-from`.

docs/reference/run.md

@@ -590,7 +590,11 @@ the container exits**, you can add the `--rm` flag:
 
 > **Note**: When you set the `--rm` flag, Docker also removes the volumes
 associated with the container when the container is removed. This is similar
-to running `docker rm -v my-container`.
+to running `docker rm -v my-container`. Only volumes that are specified without a
+name are removed. For example, with
+`docker run --rm -v /foo -v awesome:/bar busybox top`, the volume for `/foo` will be removed,
+but the volume for `/bar` will not. Volumes inheritted via `--volumes-from` will be removed
+with the same logic -- if the original volume was specified with a name it will **not** be removed.
 
 ## Security configuration
     --security-opt="label:user:USER"   : Set the label user for the container

man/docker-rm.1.md

@@ -48,6 +48,22 @@ command. The use that name as follows:
 
     docker rm hopeful_morse
 
+## Removing a container and all associated volumes
+
+  $ docker rm -v redis
+  redis
+
+This command will remove the container and any volumes associated with it.
+Note that if a volume was specified with a name, it will not be removed.
+
+  $ docker create -v awesome:/foo -v /bar --name hello redis
+  hello
+  $ docker rm -v hello
+
+In this example, the volume for `/foo` will remain in tact, but the volume for
+`/bar` will be removed. The same behavior holds for volumes inherited with
+`--volumes-from`.
+
 # HISTORY
 April 2014, Originally compiled by William Henry (whenry at redhat dot com)
 based on docker.com source material and internal work.