xref: /linux-6.15/include/linux/sched/user.h (revision 00a62703)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_USER_H
3 #define _LINUX_SCHED_USER_H
4 
5 #include <linux/uidgid.h>
6 #include <linux/atomic.h>
7 #include <linux/ratelimit.h>
8 
9 struct key;
10 
11 /*
12  * Some day this will be a full-fledged user tracking system..
13  */
14 struct user_struct {
15 	atomic_t __count;	/* reference count */
16 	atomic_t processes;	/* How many processes does this user have? */
17 	atomic_t sigpending;	/* How many pending signals does this user have? */
18 #ifdef CONFIG_FANOTIFY
19 	atomic_t fanotify_listeners;
20 #endif
21 #ifdef CONFIG_EPOLL
22 	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
23 #endif
24 #ifdef CONFIG_POSIX_MQUEUE
25 	/* protected by mq_lock	*/
26 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
27 #endif
28 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
29 	unsigned long unix_inflight;	/* How many files in flight in unix sockets */
30 	atomic_long_t pipe_bufs;  /* how many pages are allocated in pipe buffers */
31 
32 #ifdef CONFIG_KEYS
33 	struct key *uid_keyring;	/* UID specific keyring */
34 	struct key *session_keyring;	/* UID's default session keyring */
35 #endif
36 
37 	/* Hash table maintenance information */
38 	struct hlist_node uidhash_node;
39 	kuid_t uid;
40 
41 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL) || \
42     defined(CONFIG_NET)
43 	atomic_long_t locked_vm;
44 #endif
45 
46 	/* Miscellaneous per-user rate limit */
47 	struct ratelimit_state ratelimit;
48 };
49 
50 extern int uids_sysfs_init(void);
51 
52 extern struct user_struct *find_user(kuid_t);
53 
54 extern struct user_struct root_user;
55 #define INIT_USER (&root_user)
56 
57 
58 /* per-UID process charging. */
59 extern struct user_struct * alloc_uid(kuid_t);
60 static inline struct user_struct *get_uid(struct user_struct *u)
61 {
62 	atomic_inc(&u->__count);
63 	return u;
64 }
65 extern void free_uid(struct user_struct *);
66 
67 #endif /* _LINUX_SCHED_USER_H */
68