diff options
| author | Christian Brauner <brauner@kernel.org> | 2025-10-29 13:20:29 +0100 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-11-03 17:41:17 +0100 |
| commit | 3c1a52f2a6c865464babe7a85c2796aa31cc9744 (patch) | |
| tree | 471aadad5cbb7065da904ea1b3c28c4bf3746282 /include/linux/ns_common.h | |
| parent | 3760342fd6312416491d536144e39297fa5b1950 (diff) | |
nstree: maintain list of owned namespaces
The namespace tree doesn't express the ownership concept of namespace
appropriately. Maintain a list of directly owned namespaces per user
namespace. This will allow userspace and the kernel to use the listns()
system call to walk the namespace tree by owning user namespace. The
rbtree is used to find the relevant namespace entry point which allows
to continue iteration and the owner list can be used to walk the tree
completely lock free.
Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-16-2e6f823ebdc0@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/linux/ns_common.h')
| -rw-r--r-- | include/linux/ns_common.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/ns_common.h b/include/linux/ns_common.h index 009a6dea724f..698aa2f7f486 100644 --- a/include/linux/ns_common.h +++ b/include/linux/ns_common.h @@ -116,6 +116,12 @@ struct ns_common { struct rb_node ns_tree_node; struct list_head ns_list_node; }; + struct /* namespace ownership rbtree and list */ { + struct rb_root ns_owner_tree; /* rbtree of namespaces owned by this namespace */ + struct list_head ns_owner; /* list of namespaces owned by this namespace */ + struct rb_node ns_owner_tree_node; /* node in the owner namespace's rbtree */ + struct list_head ns_owner_entry; /* node in the owner namespace's ns_owned list */ + }; atomic_t __ns_ref_active; /* do not use directly */ }; struct rcu_head ns_rcu; @@ -216,6 +222,8 @@ static __always_inline bool is_initial_namespace(struct ns_common *ns) .__ns_ref = REFCOUNT_INIT(refs), \ .__ns_ref_active = ATOMIC_INIT(1), \ .ns_list_node = LIST_HEAD_INIT(nsname.ns.ns_list_node), \ + .ns_owner_entry = LIST_HEAD_INIT(nsname.ns.ns_owner_entry), \ + .ns_owner = LIST_HEAD_INIT(nsname.ns.ns_owner), \ } #define ns_common_init(__ns) \ |