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>
diff --git a/fs/namespace.c b/fs/namespace.c
index ed0708f..0f0cf93 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -21,7 +21,7 @@
 #include <linux/fs_struct.h>	/* get_fs_root et.al. */
 #include <linux/fsnotify.h>	/* fsnotify_vfsmount_delete */
 #include <linux/uaccess.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 #include "pnode.h"
 #include "internal.h"
 
@@ -1350,13 +1350,13 @@
 	 * mount namespace loop?
 	 */
 	struct inode *inode = path->dentry->d_inode;
-	struct proc_inode *ei;
+	struct proc_ns *ei;
 	struct mnt_namespace *mnt_ns;
 
 	if (!proc_ns_inode(inode))
 		return false;
 
-	ei = PROC_I(inode);
+	ei = get_proc_ns(inode);
 	if (ei->ns_ops != &mntns_operations)
 		return false;
 
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index bd2f764..073aea6 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -51,8 +51,8 @@
 		sysctl_head_put(head);
 	}
 	/* Release any associated namespace */
-	ns_ops = PROC_I(inode)->ns_ops;
-	ns = PROC_I(inode)->ns;
+	ns_ops = PROC_I(inode)->ns.ns_ops;
+	ns = PROC_I(inode)->ns.ns;
 	if (ns_ops && ns)
 		ns_ops->put(ns);
 }
@@ -73,8 +73,8 @@
 	ei->pde = NULL;
 	ei->sysctl = NULL;
 	ei->sysctl_entry = NULL;
-	ei->ns = NULL;
-	ei->ns_ops = NULL;
+	ei->ns.ns = NULL;
+	ei->ns.ns_ops = NULL;
 	inode = &ei->vfs_inode;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 	return inode;
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index 66b51c0..54bdc67 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -51,7 +51,7 @@
 static char *ns_dname(struct dentry *dentry, char *buffer, int buflen)
 {
 	struct inode *inode = dentry->d_inode;
-	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
+	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns.ns_ops;
 
 	return dynamic_dname(dentry, buffer, buflen, "%s:[%lu]",
 		ns_ops->name, inode->i_ino);
@@ -95,8 +95,8 @@
 		inode->i_op = &ns_inode_operations;
 		inode->i_mode = S_IFREG | S_IRUGO;
 		inode->i_fop = &ns_file_operations;
-		ei->ns_ops = ns_ops;
-		ei->ns = ns;
+		ei->ns.ns_ops = ns_ops;
+		ei->ns.ns = ns;
 		unlock_new_inode(inode);
 	} else {
 		ns_ops->put(ns);
@@ -128,7 +128,7 @@
 	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 		goto out_put_task;
 
-	ns_path.dentry = proc_ns_get_dentry(sb, task, ei->ns_ops);
+	ns_path.dentry = proc_ns_get_dentry(sb, task, ei->ns.ns_ops);
 	if (IS_ERR(ns_path.dentry)) {
 		error = ERR_CAST(ns_path.dentry);
 		goto out_put_task;
@@ -148,7 +148,7 @@
 {
 	struct inode *inode = dentry->d_inode;
 	struct proc_inode *ei = PROC_I(inode);
-	const struct proc_ns_operations *ns_ops = ei->ns_ops;
+	const struct proc_ns_operations *ns_ops = ei->ns.ns_ops;
 	struct task_struct *task;
 	void *ns;
 	char name[50];
@@ -202,7 +202,7 @@
 	ei = PROC_I(inode);
 	inode->i_mode = S_IFLNK|S_IRWXUGO;
 	inode->i_op = &proc_ns_link_inode_operations;
-	ei->ns_ops = ns_ops;
+	ei->ns.ns_ops = ns_ops;
 
 	d_set_d_op(dentry, &pid_dentry_operations);
 	d_add(dentry, inode);
@@ -337,6 +337,11 @@
 	return ERR_PTR(-EINVAL);
 }
 
+struct proc_ns *get_proc_ns(struct inode *inode)
+{
+	return &PROC_I(inode)->ns;
+}
+
 bool proc_ns_inode(struct inode *inode)
 {
 	return inode->i_fop == &ns_file_operations;
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 28a4d7e..8f7d8f2 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -6,6 +6,7 @@
 #include <linux/spinlock.h>
 #include <linux/magic.h>
 #include <linux/atomic.h>
+#include <linux/proc_ns.h>
 
 struct net;
 struct completion;
@@ -24,18 +25,6 @@
 #define PROC_NUMBUF 13
 
 /*
- * 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,
-};
-
-/*
  * This is not completely implemented yet. The idea is to
  * create an in-memory tree (like the actual /proc filesystem
  * tree) of these proc_dir_entries, so that we can dynamically
@@ -81,10 +70,6 @@
 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
 extern int remove_proc_subtree(const char *name, struct proc_dir_entry *parent);
 
-struct pid_namespace;
-
-extern int pid_ns_prepare_proc(struct pid_namespace *ns);
-extern void pid_ns_release_proc(struct pid_namespace *ns);
 
 /*
  * proc_tty.c
@@ -132,12 +117,6 @@
 
 extern void proc_set_size(struct proc_dir_entry *, loff_t);
 extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t);
-
-extern struct file *proc_ns_fget(int fd);
-extern bool proc_ns_inode(struct inode *inode);
-
-extern int proc_alloc_inum(unsigned int *pino);
-extern void proc_free_inum(unsigned int inum);
 #else
 
 static inline void proc_flush_task(struct task_struct *task)
@@ -168,50 +147,8 @@
 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
 
-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 bool proc_ns_inode(struct inode *inode)
-{
-	return false;
-}
-
-static inline int proc_alloc_inum(unsigned int *inum)
-{
-	*inum = 1;
-	return 0;
-}
-static inline void proc_free_inum(unsigned int inum)
-{
-}
 #endif /* CONFIG_PROC_FS */
 
-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);
-};
-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;
 
 union proc_op {
 	int (*proc_get_link)(struct dentry *, struct path *);
@@ -231,8 +168,7 @@
 	struct proc_dir_entry *pde;
 	struct ctl_table_header *sysctl;
 	struct ctl_table *sysctl_entry;
-	void *ns;
-	const struct proc_ns_operations *ns_ops;
+	struct proc_ns ns;
 	struct inode vfs_inode;
 };
 
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
new file mode 100644
index 0000000..34a1e10
--- /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 */
diff --git a/init/version.c b/init/version.c
index 58170f1..1a4718e 100644
--- a/init/version.c
+++ b/init/version.c
@@ -12,7 +12,7 @@
 #include <linux/utsname.h>
 #include <generated/utsrelease.h>
 #include <linux/version.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 
 #ifndef CONFIG_KALLSYMS
 #define version(a) Version_ ## a
diff --git a/ipc/msgutil.c b/ipc/msgutil.c
index 5df8e4b..8f02017 100644
--- a/ipc/msgutil.c
+++ b/ipc/msgutil.c
@@ -16,7 +16,7 @@
 #include <linux/msg.h>
 #include <linux/ipc_namespace.h>
 #include <linux/utsname.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 #include <asm/uaccess.h>
 
 #include "util.h"
diff --git a/ipc/namespace.c b/ipc/namespace.c
index 7c1fa45..7ee61bf 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -12,7 +12,7 @@
 #include <linux/fs.h>
 #include <linux/mount.h>
 #include <linux/user_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 
 #include "util.h"
 
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index afc0456..364ceab 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -22,7 +22,7 @@
 #include <linux/pid_namespace.h>
 #include <net/net_namespace.h>
 #include <linux/ipc_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 #include <linux/file.h>
 #include <linux/syscalls.h>
 
@@ -241,7 +241,7 @@
 	const struct proc_ns_operations *ops;
 	struct task_struct *tsk = current;
 	struct nsproxy *new_nsproxy;
-	struct proc_inode *ei;
+	struct proc_ns *ei;
 	struct file *file;
 	int err;
 
@@ -250,7 +250,7 @@
 		return PTR_ERR(file);
 
 	err = -EINVAL;
-	ei = PROC_I(file_inode(file));
+	ei = get_proc_ns(file_inode(file));
 	ops = ei->ns_ops;
 	if (nstype && (ops->type != nstype))
 		goto out;
diff --git a/kernel/pid.c b/kernel/pid.c
index 047dc62..686255e 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -36,6 +36,7 @@
 #include <linux/pid_namespace.h>
 #include <linux/init_task.h>
 #include <linux/syscalls.h>
+#include <linux/proc_ns.h>
 #include <linux/proc_fs.h>
 
 #define pid_hashfn(nr, ns)	\
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index c1c3dc1..4af28a8 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -15,7 +15,7 @@
 #include <linux/err.h>
 #include <linux/acct.h>
 #include <linux/slab.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 #include <linux/reboot.h>
 #include <linux/export.h>
 
diff --git a/kernel/user.c b/kernel/user.c
index e81978e..5bbb919 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -16,7 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/export.h>
 #include <linux/user_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 
 /*
  * userns count is 1 for root user, 1 for init_uts_ns,
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index b14f4d3..51855f5 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -9,7 +9,7 @@
 #include <linux/nsproxy.h>
 #include <linux/slab.h>
 #include <linux/user_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 #include <linux/highuid.h>
 #include <linux/cred.h>
 #include <linux/securebits.h>
diff --git a/kernel/utsname.c b/kernel/utsname.c
index a47fc5d..2fc8576 100644
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -15,7 +15,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/user_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 
 static struct uts_namespace *create_uts_ns(void)
 {
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 80e271d..f9765203 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -10,7 +10,8 @@
 #include <linux/idr.h>
 #include <linux/rculist.h>
 #include <linux/nsproxy.h>
-#include <linux/proc_fs.h>
+#include <linux/fs.h>
+#include <linux/proc_ns.h>
 #include <linux/file.h>
 #include <linux/export.h>
 #include <linux/user_namespace.h>
@@ -336,7 +337,7 @@
 
 struct net *get_net_ns_by_fd(int fd)
 {
-	struct proc_inode *ei;
+	struct proc_ns *ei;
 	struct file *file;
 	struct net *net;
 
@@ -344,7 +345,7 @@
 	if (IS_ERR(file))
 		return ERR_CAST(file);
 
-	ei = PROC_I(file_inode(file));
+	ei = get_proc_ns(file_inode(file));
 	if (ei->ns_ops == &netns_operations)
 		net = get_net(ei->ns);
 	else