Man pages: refactor common options: --rootfs

podman-create and -run only. The SELinux text was added
to podman-run (but not -create) in #3631, and reformatted
in #5192. I assume here that it also applies to podman-create.

Per feedback from Dan, added :s0 to SELinux context

Signed-off-by: Ed Santiago <santiago@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/docs/source/markdown/options/rootfs.md b/docs/source/markdown/options/rootfs.md
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index 000000000..a03c4eef1
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+#### **--rootfs**
+
+If specified, the first argument refers to an exploded container on the file system.
+
+This is useful to run a container without requiring any image management, the rootfs
+of the container is assumed to be managed externally.
+
+  `Overlay Rootfs Mounts`
+
+   The `:O` flag tells Podman to mount the directory from the rootfs path as
+storage using the `overlay file system`. The container processes
+can modify content within the mount point which is stored in the
+container storage in a separate directory. In overlay terms, the source
+directory will be the lower, and the container storage directory will be the
+upper. Modifications to the mount point are destroyed when the container
+finishes executing, similar to a tmpfs mount point being unmounted.
+
+Note: On **SELinux** systems, the rootfs needs the correct label, which is by default
+**unconfined_u:object_r:container_file_t:s0**.