There's a lot of information that namespace implementers don't need to know about at all. Encapsulate this all in the initialization helper. Signed-off-by: Christian Brauner --- fs/namespace.c | 5 +++-- include/linux/ns_common.h | 41 +++++++++++++++++++++++++++++++++++++++-- ipc/namespace.c | 2 +- kernel/cgroup/namespace.c | 2 +- kernel/nscommon.c | 17 ++++++++--------- kernel/pid_namespace.c | 2 +- kernel/time/namespace.c | 2 +- kernel/user_namespace.c | 2 +- kernel/utsname.c | 2 +- net/core/net_namespace.c | 2 +- 10 files changed, 57 insertions(+), 20 deletions(-) diff --git a/fs/namespace.c b/fs/namespace.c index 09e4ecd44972..31eb0e8f21eb 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -4105,8 +4105,9 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a } if (anon) - new_ns->ns.inum = MNT_NS_ANON_INO; - ret = ns_common_init(&new_ns->ns, &mntns_operations, !anon); + ret = ns_common_init_inum(new_ns, &mntns_operations, MNT_NS_ANON_INO); + else + ret = ns_common_init(new_ns, &mntns_operations); if (ret) { kfree(new_ns); dec_mnt_namespaces(ucounts); diff --git a/include/linux/ns_common.h b/include/linux/ns_common.h index 78b17fe80b62..284bba2b7c43 100644 --- a/include/linux/ns_common.h +++ b/include/linux/ns_common.h @@ -16,6 +16,15 @@ struct time_namespace; struct user_namespace; struct uts_namespace; +extern struct cgroup_namespace init_cgroup_ns; +extern struct ipc_namespace init_ipc_ns; +extern struct mnt_namespace *init_mnt_ns; +extern struct net init_net; +extern struct pid_namespace init_pid_ns; +extern struct time_namespace init_time_ns; +extern struct user_namespace init_user_ns; +extern struct uts_namespace init_uts_ns; + struct ns_common { struct dentry *stashed; const struct proc_ns_operations *ops; @@ -31,8 +40,7 @@ struct ns_common { }; }; -int ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops, - bool alloc_inum); +int __ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops, int inum); #define to_ns_common(__ns) \ _Generic((__ns), \ @@ -45,4 +53,33 @@ int ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops, struct user_namespace *: &(__ns)->ns, \ struct uts_namespace *: &(__ns)->ns) +#define ns_init_inum(__ns) \ + _Generic((__ns), \ + struct cgroup_namespace *: CGROUP_NS_INIT_INO, \ + struct ipc_namespace *: IPC_NS_INIT_INO, \ + struct mnt_namespace *: MNT_NS_INIT_INO, \ + struct net *: NET_NS_INIT_INO, \ + struct pid_namespace *: PID_NS_INIT_INO, \ + struct time_namespace *: TIME_NS_INIT_INO, \ + struct user_namespace *: USER_NS_INIT_INO, \ + struct uts_namespace *: UTS_NS_INIT_INO) + +#define ns_init_ns(__ns) \ + _Generic((__ns), \ + struct cgroup_namespace *: &init_cgroup_ns, \ + struct ipc_namespace *: &init_ipc_ns, \ + struct mnt_namespace *: init_mnt_ns, \ + struct net *: &init_net, \ + struct pid_namespace *: &init_pid_ns, \ + struct time_namespace *: &init_time_ns, \ + struct user_namespace *: &init_user_ns, \ + struct uts_namespace *: &init_uts_ns) + +#define ns_common_init(__ns, __ops) \ + __ns_common_init(&(__ns)->ns, __ops, \ + (((__ns) == ns_init_ns(__ns)) ? ns_init_inum(__ns) : 0)) + +#define ns_common_init_inum(__ns, __ops, __inum) \ + __ns_common_init(&(__ns)->ns, __ops, __inum) + #endif diff --git a/ipc/namespace.c b/ipc/namespace.c index 89588819956b..0f8bbd18a475 100644 --- a/ipc/namespace.c +++ b/ipc/namespace.c @@ -62,7 +62,7 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns, if (ns == NULL) goto fail_dec; - err = ns_common_init(&ns->ns, &ipcns_operations, true); + err = ns_common_init(ns, &ipcns_operations); if (err) goto fail_free; diff --git a/kernel/cgroup/namespace.c b/kernel/cgroup/namespace.c index 5a327914b565..d928c557e28b 100644 --- a/kernel/cgroup/namespace.c +++ b/kernel/cgroup/namespace.c @@ -27,7 +27,7 @@ static struct cgroup_namespace *alloc_cgroup_ns(void) new_ns = kzalloc(sizeof(struct cgroup_namespace), GFP_KERNEL_ACCOUNT); if (!new_ns) return ERR_PTR(-ENOMEM); - ret = ns_common_init(&new_ns->ns, &cgroupns_operations, true); + ret = ns_common_init(new_ns, &cgroupns_operations); if (ret) return ERR_PTR(ret); ns_tree_add(new_ns); diff --git a/kernel/nscommon.c b/kernel/nscommon.c index e10fad8afe61..c3a90bb665ad 100644 --- a/kernel/nscommon.c +++ b/kernel/nscommon.c @@ -1,21 +1,20 @@ // SPDX-License-Identifier: GPL-2.0-only #include +#include -int ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops, - bool alloc_inum) +int __ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops, int inum) { - if (alloc_inum && !ns->inum) { - int ret; - ret = proc_alloc_inum(&ns->inum); - if (ret) - return ret; - } refcount_set(&ns->count, 1); ns->stashed = NULL; ns->ops = ops; ns->ns_id = 0; RB_CLEAR_NODE(&ns->ns_tree_node); INIT_LIST_HEAD(&ns->ns_list_node); - return 0; + + if (inum) { + ns->inum = inum; + return 0; + } + return proc_alloc_inum(&ns->inum); } diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 9b327420309e..170757c265c2 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -103,7 +103,7 @@ static struct pid_namespace *create_pid_namespace(struct user_namespace *user_ns if (ns->pid_cachep == NULL) goto out_free_idr; - err = ns_common_init(&ns->ns, &pidns_operations, true); + err = ns_common_init(ns, &pidns_operations); if (err) goto out_free_idr; diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c index 20b65f90549e..ce8e952104a7 100644 --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -97,7 +97,7 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns, if (!ns->vvar_page) goto fail_free; - err = ns_common_init(&ns->ns, &timens_operations, true); + err = ns_common_init(ns, &timens_operations); if (err) goto fail_free_page; diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index cfb0e28f2779..db9f0463219c 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -126,7 +126,7 @@ int create_user_ns(struct cred *new) ns->parent_could_setfcap = cap_raised(new->cap_effective, CAP_SETFCAP); - ret = ns_common_init(&ns->ns, &userns_operations, true); + ret = ns_common_init(ns, &userns_operations); if (ret) goto fail_free; diff --git a/kernel/utsname.c b/kernel/utsname.c index a682830742d3..399888be66bd 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -50,7 +50,7 @@ static struct uts_namespace *clone_uts_ns(struct user_namespace *user_ns, if (!ns) goto fail_dec; - err = ns_common_init(&ns->ns, &utsns_operations, true); + err = ns_common_init(ns, &utsns_operations); if (err) goto fail_free; diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 897f4927df9e..fdb266bbdf93 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -409,7 +409,7 @@ static __net_init int preinit_net(struct net *net, struct user_namespace *user_n ns_ops = NULL; #endif - ret = ns_common_init(&net->ns, ns_ops, true); + ret = ns_common_init(net, ns_ops); if (ret) return ret; -- 2.47.3