include/linux/sched/user.h

   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/refcount.h>
   8 #include <linux/ratelimit.h>
   9
  10 /*
  11  * Some day this will be a full-fledged user tracking system..
  12  */
  13 struct user_struct {
  14         refcount_t __count;     /* reference count */
  15         atomic_t processes;     /* How many processes does this user have? */
  16         atomic_t sigpending;    /* How many pending signals does this user have? */
  17 #ifdef CONFIG_EPOLL
  18         atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
  19 #endif
  20 #ifdef CONFIG_POSIX_MQUEUE
  21         /* protected by mq_lock */
  22         unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
  23 #endif
  24         unsigned long locked_shm; /* How many pages of mlocked shm ? */
  25         unsigned long unix_inflight;    /* How many files in flight in unix sockets */
  26         atomic_long_t pipe_bufs;  /* how many pages are allocated in pipe buffers */
  27
  28         /* Hash table maintenance information */
  29         struct hlist_node uidhash_node;
  30         kuid_t uid;
  31
  32 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL) || \
  33     defined(CONFIG_NET) || defined(CONFIG_IO_URING)
  34         atomic_long_t locked_vm;
  35 #endif
  36 #ifdef CONFIG_WATCH_QUEUE
  37         atomic_t nr_watches;    /* The number of watches this user currently has */
  38 #endif
  39
  40         /* Miscellaneous per-user rate limit */
  41         struct ratelimit_state ratelimit;
  42 };
  43
  44 extern int uids_sysfs_init(void);
  45
  46 extern struct user_struct *find_user(kuid_t);
  47
  48 extern struct user_struct root_user;
  49 #define INIT_USER (&root_user)
  50
  51
  52 /* per-UID process charging. */
  53 extern struct user_struct * alloc_uid(kuid_t);
  54 static inline struct user_struct *get_uid(struct user_struct *u)
  55 {
  56         refcount_inc(&u->__count);
  57         return u;
  58 }
  59 extern void free_uid(struct user_struct *);
  60
  61 #endif /* _LINUX_SCHED_USER_H */