include/linux/proc_ns.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * procfs namespace bits
   4  */
   5 #ifndef _LINUX_PROC_NS_H
   6 #define _LINUX_PROC_NS_H
   7
   8 #include <linux/ns_common.h>
   9
  10 struct pid_namespace;
  11 struct nsproxy;
  12 struct path;
  13 struct task_struct;
  14 struct inode;
  15
  16 struct proc_ns_operations {
  17         const char *name;
  18         const char *real_ns_name;
  19         int type;
  20         struct ns_common *(*get)(struct task_struct *task);
  21         void (*put)(struct ns_common *ns);
  22         int (*install)(struct nsproxy *nsproxy, struct ns_common *ns);
  23         struct user_namespace *(*owner)(struct ns_common *ns);
  24         struct ns_common *(*get_parent)(struct ns_common *ns);
  25 } __randomize_layout;
  26
  27 extern const struct proc_ns_operations netns_operations;
  28 extern const struct proc_ns_operations utsns_operations;
  29 extern const struct proc_ns_operations ipcns_operations;
  30 extern const struct proc_ns_operations pidns_operations;
  31 extern const struct proc_ns_operations pidns_for_children_operations;
  32 extern const struct proc_ns_operations userns_operations;
  33 extern const struct proc_ns_operations mntns_operations;
  34 extern const struct proc_ns_operations cgroupns_operations;
  35
  36 /*
  37  * We always define these enumerators
  38  */
  39 enum {
  40         PROC_ROOT_INO           = 1,
  41         PROC_IPC_INIT_INO       = 0xEFFFFFFFU,
  42         PROC_UTS_INIT_INO       = 0xEFFFFFFEU,
  43         PROC_USER_INIT_INO      = 0xEFFFFFFDU,
  44         PROC_PID_INIT_INO       = 0xEFFFFFFCU,
  45         PROC_CGROUP_INIT_INO    = 0xEFFFFFFBU,
  46 };
  47
  48 #ifdef CONFIG_PROC_FS
  49
  50 extern int pid_ns_prepare_proc(struct pid_namespace *ns);
  51 extern void pid_ns_release_proc(struct pid_namespace *ns);
  52 extern int proc_alloc_inum(unsigned int *pino);
  53 extern void proc_free_inum(unsigned int inum);
  54
  55 #else /* CONFIG_PROC_FS */
  56
  57 static inline int pid_ns_prepare_proc(struct pid_namespace *ns) { return 0; }
  58 static inline void pid_ns_release_proc(struct pid_namespace *ns) {}
  59
  60 static inline int proc_alloc_inum(unsigned int *inum)
  61 {
  62         *inum = 1;
  63         return 0;
  64 }
  65 static inline void proc_free_inum(unsigned int inum) {}
  66
  67 #endif /* CONFIG_PROC_FS */
  68
  69 static inline int ns_alloc_inum(struct ns_common *ns)
  70 {
  71         atomic_long_set(&ns->stashed, 0);
  72         return proc_alloc_inum(&ns->inum);
  73 }
  74
  75 #define ns_free_inum(ns) proc_free_inum((ns)->inum)
  76
  77 extern struct file *proc_ns_fget(int fd);
  78 #define get_proc_ns(inode) ((struct ns_common *)(inode)->i_private)
  79 extern void *ns_get_path(struct path *path, struct task_struct *task,
  80                         const struct proc_ns_operations *ns_ops);
  81 typedef struct ns_common *ns_get_path_helper_t(void *);
  82 extern void *ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb,
  83                             void *private_data);
  84
  85 extern int ns_get_name(char *buf, size_t size, struct task_struct *task,
  86                         const struct proc_ns_operations *ns_ops);
  87 extern void nsfs_init(void);
  88
  89 #endif /* _LINUX_PROC_NS_H */