forked from mirrors/linux
		
	New pseudo-filesystem: nsfs. Targets of /proc/*/ns/* live there now. It's not mountable (not even registered, so it's not in /proc/filesystems, etc.). Files on it *are* bindable - we explicitly permit that in do_loopback(). This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well. get_proc_ns() is a macro now (it's simply returning ->i_private; would have been an inline, if not for header ordering headache). proc_ns_inode() is an ex-parrot. The interface used in procfs is ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops). Dentries and inodes are never hashed; a non-counting reference to dentry is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path() if present. See ns_get_path()/ns_prune_dentry/nsfs_evict() for details of that mechanism. As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt; it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets from ns_get_path(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
		
			
				
	
	
		
			77 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * procfs namespace bits
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 */
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#ifndef _LINUX_PROC_NS_H
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#define _LINUX_PROC_NS_H
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#include <linux/ns_common.h>
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struct pid_namespace;
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struct nsproxy;
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struct path;
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struct proc_ns_operations {
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	const char *name;
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	int type;
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	struct ns_common *(*get)(struct task_struct *task);
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	void (*put)(struct ns_common *ns);
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	int (*install)(struct nsproxy *nsproxy, struct ns_common *ns);
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};
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extern const struct proc_ns_operations netns_operations;
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extern const struct proc_ns_operations utsns_operations;
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extern const struct proc_ns_operations ipcns_operations;
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extern const struct proc_ns_operations pidns_operations;
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extern const struct proc_ns_operations userns_operations;
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extern const struct proc_ns_operations mntns_operations;
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/*
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 * We always define these enumerators
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 */
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enum {
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	PROC_ROOT_INO		= 1,
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	PROC_IPC_INIT_INO	= 0xEFFFFFFFU,
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	PROC_UTS_INIT_INO	= 0xEFFFFFFEU,
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	PROC_USER_INIT_INO	= 0xEFFFFFFDU,
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	PROC_PID_INIT_INO	= 0xEFFFFFFCU,
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};
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#ifdef CONFIG_PROC_FS
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extern int pid_ns_prepare_proc(struct pid_namespace *ns);
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extern void pid_ns_release_proc(struct pid_namespace *ns);
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extern int proc_alloc_inum(unsigned int *pino);
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extern void proc_free_inum(unsigned int inum);
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#else /* CONFIG_PROC_FS */
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static inline int pid_ns_prepare_proc(struct pid_namespace *ns) { return 0; }
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static inline void pid_ns_release_proc(struct pid_namespace *ns) {}
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static inline int proc_alloc_inum(unsigned int *inum)
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{
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	*inum = 1;
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	return 0;
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}
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static inline void proc_free_inum(unsigned int inum) {}
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#endif /* CONFIG_PROC_FS */
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static inline int ns_alloc_inum(struct ns_common *ns)
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{
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	atomic_long_set(&ns->stashed, 0);
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	return proc_alloc_inum(&ns->inum);
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}
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#define ns_free_inum(ns) proc_free_inum((ns)->inum)
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extern struct file *proc_ns_fget(int fd);
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#define get_proc_ns(inode) ((struct ns_common *)(inode)->i_private)
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extern void *ns_get_path(struct path *path, struct task_struct *task,
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			const struct proc_ns_operations *ns_ops);
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extern int ns_get_name(char *buf, size_t size, struct task_struct *task,
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			const struct proc_ns_operations *ns_ops);
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extern void nsfs_init(void);
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#endif /* _LINUX_PROC_NS_H */
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