proc: Split the namespace stuff out into linux/proc_ns.h

Split the proc namespace stuff out into linux/proc_ns.h.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: Serge E. Hallyn <serge.hallyn@ubuntu.com>
cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 74 insertions, 0 deletions

diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
new file mode 100644
index 000000000000..34a1e105bef4
--- /dev/null
+++ b/include/linux/proc_ns.h
@@ -0,0 +1,74 @@
+/*
+ * procfs namespace bits
+ */
+#ifndef _LINUX_PROC_NS_H
+#define _LINUX_PROC_NS_H
+
+struct pid_namespace;
+struct nsproxy;
+
+struct proc_ns_operations {
+	const char *name;
+	int type;
+	void *(*get)(struct task_struct *task);
+	void (*put)(void *ns);
+	int (*install)(struct nsproxy *nsproxy, void *ns);
+	unsigned int (*inum)(void *ns);
+};
+
+struct proc_ns {
+	void *ns;
+	const struct proc_ns_operations *ns_ops;
+};
+
+extern const struct proc_ns_operations netns_operations;
+extern const struct proc_ns_operations utsns_operations;
+extern const struct proc_ns_operations ipcns_operations;
+extern const struct proc_ns_operations pidns_operations;
+extern const struct proc_ns_operations userns_operations;
+extern const struct proc_ns_operations mntns_operations;
+
+/*
+ * We always define these enumerators
+ */
+enum {
+	PROC_ROOT_INO		= 1,
+	PROC_IPC_INIT_INO	= 0xEFFFFFFFU,
+	PROC_UTS_INIT_INO	= 0xEFFFFFFEU,
+	PROC_USER_INIT_INO	= 0xEFFFFFFDU,
+	PROC_PID_INIT_INO	= 0xEFFFFFFCU,
+};
+
+#ifdef CONFIG_PROC_FS
+
+extern int pid_ns_prepare_proc(struct pid_namespace *ns);
+extern void pid_ns_release_proc(struct pid_namespace *ns);
+extern struct file *proc_ns_fget(int fd);
+extern struct proc_ns *get_proc_ns(struct inode *);
+extern int proc_alloc_inum(unsigned int *pino);
+extern void proc_free_inum(unsigned int inum);
+extern bool proc_ns_inode(struct inode *inode);
+
+#else /* CONFIG_PROC_FS */
+
+static inline int pid_ns_prepare_proc(struct pid_namespace *ns) { return 0; }
+static inline void pid_ns_release_proc(struct pid_namespace *ns) {}
+
+static inline struct file *proc_ns_fget(int fd)
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline struct proc_ns *get_proc_ns(struct inode *inode) { return NULL; }
+
+static inline int proc_alloc_inum(unsigned int *inum)
+{
+	*inum = 1;
+	return 0;
+}
+static inline void proc_free_inum(unsigned int inum) {}
+static inline bool proc_ns_inode(struct inode *inode) { return false; }
+
+#endif /* CONFIG_PROC_FS */
+
+#endif /* _LINUX_PROC_NS_H */