Unverified Commit d9a44089 authored by Christian Brauner's avatar Christian Brauner
Browse files

fs: use boolean to indicate anonymous mount namespace 

Stop playing games with the namespace id and use a boolean instead:

* This will remove the special-casing we need to do everywhere for mount
  namespaces.

* It will allow us to use asserts on the namespace id for initial
  namespaces everywhere.

* It will allow us to put anonymous mount namespaces on the namespaces
  trees in the future and thus make them available to statmount() and
  listmount().

Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-10-e8a9264e0fb9@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 6bf25385

fs/mount.h

+2 −1
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ struct mnt_namespace { 
	unsigned int		nr_mounts; /* # of mounts in the namespace */

	unsigned int		pending_mounts;

	refcount_t		passive; /* number references not pinning @mounts */

	bool			is_anon;

} __randomize_layout;



struct mnt_pcp {
@@ -175,7 +176,7 @@ static inline bool is_local_mountpoint(const struct dentry *dentry) 


static inline bool is_anon_ns(struct mnt_namespace *ns)

{

	return ns->ns.ns_id == 0;

	return ns->is_anon;

}



static inline bool anon_ns_root(const struct mount *m)

fs/namespace.c

+3 −2
Original line number Diff line number Diff line
@@ -4093,8 +4093,9 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a 
		dec_mnt_namespaces(ucounts);

		return ERR_PTR(ret);

	}

	if (!anon)

	ns_tree_gen_id(new_ns);



	new_ns->is_anon = anon;

	refcount_set(&new_ns->passive, 1);

	new_ns->mounts = RB_ROOT;

	init_waitqueue_head(&new_ns->poll);