File: /usr/include/linux/sched.h
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3
4 #include <asm/param.h> /* for HZ */
5
6 extern unsigned long event;
7
8 #include <linux/config.h>
9 #include <linux/binfmts.h>
10 #include <linux/personality.h>
11 #include <linux/threads.h>
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/times.h>
15 #include <linux/timex.h>
16
17 #include <asm/system.h>
18 #include <asm/semaphore.h>
19 #include <asm/page.h>
20 #include <asm/ptrace.h>
21 #include <asm/mmu.h>
22
23 #include <linux/smp.h>
24 #include <linux/tty.h>
25 #include <linux/sem.h>
26 #include <linux/signal.h>
27 #include <linux/securebits.h>
28 #include <linux/fs_struct.h>
29
30 /*
31 * cloning flags:
32 */
33 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
34 #define CLONE_VM 0x00000100 /* set if VM shared between processes */
35 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */
36 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */
37 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
38 #define CLONE_PID 0x00001000 /* set if pid shared */
39 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
40 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
41 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
42 #define CLONE_THREAD 0x00010000 /* Same thread group? */
43
44 #define CLONE_SIGNAL (CLONE_SIGHAND | CLONE_THREAD)
45
46 /*
47 * These are the constant used to fake the fixed-point load-average
48 * counting. Some notes:
49 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
50 * a load-average precision of 10 bits integer + 11 bits fractional
51 * - if you want to count load-averages more often, you need more
52 * precision, or rounding will get you. With 2-second counting freq,
53 * the EXP_n values would be 1981, 2034 and 2043 if still using only
54 * 11 bit fractions.
55 */
56 extern unsigned long avenrun[]; /* Load averages */
57
58 #define FSHIFT 11 /* nr of bits of precision */
59 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
60 #define LOAD_FREQ (5*HZ) /* 5 sec intervals */
61 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
62 #define EXP_5 2014 /* 1/exp(5sec/5min) */
63 #define EXP_15 2037 /* 1/exp(5sec/15min) */
64
65 #define CALC_LOAD(load,exp,n) \
66 load *= exp; \
67 load += n*(FIXED_1-exp); \
68 load >>= FSHIFT;
69
70 #define CT_TO_SECS(x) ((x) / HZ)
71 #define CT_TO_USECS(x) (((x) % HZ) * 1000000/HZ)
72
73 extern int nr_running, nr_threads;
74 extern int last_pid;
75
76 #include <linux/fs.h>
77 #include <linux/time.h>
78 #include <linux/param.h>
79 #include <linux/resource.h>
80 #include <linux/timer.h>
81
82 #include <asm/processor.h>
83
84 #define TASK_RUNNING 0
85 #define TASK_INTERRUPTIBLE 1
86 #define TASK_UNINTERRUPTIBLE 2
87 #define TASK_ZOMBIE 4
88 #define TASK_STOPPED 8
89
90 #define __set_task_state(tsk, state_value) \
91 do { (tsk)->state = (state_value); } while (0)
92 #ifdef CONFIG_SMP
93 #define set_task_state(tsk, state_value) \
94 set_mb((tsk)->state, (state_value))
95 #else
96 #define set_task_state(tsk, state_value) \
97 __set_task_state((tsk), (state_value))
98 #endif
99
100 #define __set_current_state(state_value) \
101 do { current->state = (state_value); } while (0)
102 #ifdef CONFIG_SMP
103 #define set_current_state(state_value) \
104 set_mb(current->state, (state_value))
105 #else
106 #define set_current_state(state_value) \
107 __set_current_state(state_value)
108 #endif
109
110 /*
111 * Scheduling policies
112 */
113 #define SCHED_OTHER 0
114 #define SCHED_FIFO 1
115 #define SCHED_RR 2
116
117 /*
118 * This is an additional bit set when we want to
119 * yield the CPU for one re-schedule..
120 */
121 #define SCHED_YIELD 0x10
122
123 struct sched_param {
124 int sched_priority;
125 };
126
127 #ifdef __KERNEL__
128
129 #include <linux/spinlock.h>
130
131 /*
132 * This serializes "schedule()" and also protects
133 * the run-queue from deletions/modifications (but
134 * _adding_ to the beginning of the run-queue has
135 * a separate lock).
136 */
137 extern rwlock_t tasklist_lock;
138 extern spinlock_t runqueue_lock;
139 extern spinlock_t mmlist_lock;
140
141 extern void sched_init(void);
142 extern void init_idle(void);
143 extern void show_state(void);
144 extern void cpu_init (void);
145 extern void trap_init(void);
146 extern void update_process_times(int user);
147 extern void update_one_process(struct task_struct *p, unsigned long user,
148 unsigned long system, int cpu);
149
150 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
151 extern signed long FASTCALL(schedule_timeout(signed long timeout));
152 asmlinkage void schedule(void);
153
154 extern int schedule_task(struct tq_struct *task);
155 extern void flush_scheduled_tasks(void);
156 extern int start_context_thread(void);
157 extern int current_is_keventd(void);
158
159 /*
160 * The default fd array needs to be at least BITS_PER_LONG,
161 * as this is the granularity returned by copy_fdset().
162 */
163 #define NR_OPEN_DEFAULT BITS_PER_LONG
164
165 /*
166 * Open file table structure
167 */
168 struct files_struct {
169 atomic_t count;
170 rwlock_t file_lock;
171 int max_fds;
172 int max_fdset;
173 int next_fd;
174 struct file ** fd; /* current fd array */
175 fd_set *close_on_exec;
176 fd_set *open_fds;
177 fd_set close_on_exec_init;
178 fd_set open_fds_init;
179 struct file * fd_array[NR_OPEN_DEFAULT];
180 };
181
182 #define INIT_FILES \
183 { \
184 count: ATOMIC_INIT(1), \
185 file_lock: RW_LOCK_UNLOCKED, \
186 max_fds: NR_OPEN_DEFAULT, \
187 max_fdset: __FD_SETSIZE, \
188 next_fd: 0, \
189 fd: &init_files.fd_array[0], \
190 close_on_exec: &init_files.close_on_exec_init, \
191 open_fds: &init_files.open_fds_init, \
192 close_on_exec_init: { { 0, } }, \
193 open_fds_init: { { 0, } }, \
194 fd_array: { NULL, } \
195 }
196
197 /* Maximum number of active map areas.. This is a random (large) number */
198 #define DEFAULT_MAX_MAP_COUNT (65536)
199
200 extern int max_map_count;
201
202 /* Number of map areas at which the AVL tree is activated. This is arbitrary. */
203 #define AVL_MIN_MAP_COUNT 32
204
205 struct mm_struct {
206 struct vm_area_struct * mmap; /* list of VMAs */
207 struct vm_area_struct * mmap_avl; /* tree of VMAs */
208 struct vm_area_struct * mmap_cache; /* last find_vma result */
209 pgd_t * pgd;
210 atomic_t mm_users; /* How many users with user space? */
211 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
212 int map_count; /* number of VMAs */
213 struct semaphore mmap_sem;
214 spinlock_t page_table_lock;
215
216 struct list_head mmlist; /* List of all active mm's */
217
218 unsigned long start_code, end_code, start_data, end_data;
219 unsigned long start_brk, brk, start_stack;
220 unsigned long arg_start, arg_end, env_start, env_end;
221 unsigned long rss, total_vm, locked_vm;
222 unsigned long def_flags;
223 unsigned long cpu_vm_mask;
224 unsigned long swap_address;
225
226 /* Architecture-specific MM context */
227 mm_context_t context;
228 };
229
230 extern int mmlist_nr;
231
232 #define INIT_MM(name) \
233 { \
234 mmap: &init_mmap, \
235 mmap_avl: NULL, \
236 mmap_cache: NULL, \
237 pgd: swapper_pg_dir, \
238 mm_users: ATOMIC_INIT(2), \
239 mm_count: ATOMIC_INIT(1), \
240 map_count: 1, \
241 mmap_sem: __MUTEX_INITIALIZER(name.mmap_sem), \
242 page_table_lock: SPIN_LOCK_UNLOCKED, \
243 mmlist: LIST_HEAD_INIT(name.mmlist), \
244 }
245
246 struct signal_struct {
247 atomic_t count;
248 struct k_sigaction action[_NSIG];
249 spinlock_t siglock;
250 };
251
252
253 #define INIT_SIGNALS { \
254 count: ATOMIC_INIT(1), \
255 action: { {{0,}}, }, \
256 siglock: SPIN_LOCK_UNLOCKED \
257 }
258
259 /*
260 * Some day this will be a full-fledged user tracking system..
261 */
262 struct user_struct {
263 atomic_t __count; /* reference count */
264 atomic_t processes; /* How many processes does this user have? */
265 atomic_t files; /* How many open files does this user have? */
266
267 /* Hash table maintenance information */
268 struct user_struct *next, **pprev;
269 uid_t uid;
270 };
271
272 #define get_current_user() ({ \
273 struct user_struct *__user = current->user; \
274 atomic_inc(&__user->__count); \
275 __user; })
276
277 extern struct user_struct root_user;
278 #define INIT_USER (&root_user)
279
280 struct task_struct {
281 /*
282 * offsets of these are hardcoded elsewhere - touch with care
283 */
284 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
285 unsigned long flags; /* per process flags, defined below */
286 int sigpending;
287 mm_segment_t addr_limit; /* thread address space:
288 0-0xBFFFFFFF for user-thead
289 0-0xFFFFFFFF for kernel-thread
290 */
291 struct exec_domain *exec_domain;
292 volatile long need_resched;
293 unsigned long ptrace;
294
295 int lock_depth; /* Lock depth */
296
297 /*
298 * offset 32 begins here on 32-bit platforms. We keep
299 * all fields in a single cacheline that are needed for
300 * the goodness() loop in schedule().
301 */
302 long counter;
303 long nice;
304 unsigned long policy;
305 struct mm_struct *mm;
306 int has_cpu, processor;
307 unsigned long cpus_allowed;
308 /*
309 * (only the 'next' pointer fits into the cacheline, but
310 * that's just fine.)
311 */
312 struct list_head run_list;
313 unsigned long sleep_time;
314
315 struct task_struct *next_task, *prev_task;
316 struct mm_struct *active_mm;
317
318 /* task state */
319 struct linux_binfmt *binfmt;
320 int exit_code, exit_signal;
321 int pdeath_signal; /* The signal sent when the parent dies */
322 /* ??? */
323 unsigned long personality;
324 int dumpable:1;
325 int did_exec:1;
326 pid_t pid;
327 pid_t pgrp;
328 pid_t tty_old_pgrp;
329 pid_t session;
330 pid_t tgid;
331 /* boolean value for session group leader */
332 int leader;
333 /*
334 * pointers to (original) parent process, youngest child, younger sibling,
335 * older sibling, respectively. (p->father can be replaced with
336 * p->p_pptr->pid)
337 */
338 struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
339 struct list_head thread_group;
340
341 /* PID hash table linkage. */
342 struct task_struct *pidhash_next;
343 struct task_struct **pidhash_pprev;
344
345 wait_queue_head_t wait_chldexit; /* for wait4() */
346 struct semaphore *vfork_sem; /* for vfork() */
347 unsigned long rt_priority;
348 unsigned long it_real_value, it_prof_value, it_virt_value;
349 unsigned long it_real_incr, it_prof_incr, it_virt_incr;
350 struct timer_list real_timer;
351 struct tms times;
352 unsigned long start_time;
353 long per_cpu_utime[NR_CPUS], per_cpu_stime[NR_CPUS];
354 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
355 unsigned long min_flt, maj_flt, nswap, cmin_flt, cmaj_flt, cnswap;
356 int swappable:1;
357 /* process credentials */
358 uid_t uid,euid,suid,fsuid;
359 gid_t gid,egid,sgid,fsgid;
360 int ngroups;
361 gid_t groups[NGROUPS];
362 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
363 int keep_capabilities:1;
364 struct user_struct *user;
365 /* limits */
366 struct rlimit rlim[RLIM_NLIMITS];
367 unsigned short used_math;
368 char comm[16];
369 /* file system info */
370 int link_count;
371 struct tty_struct *tty; /* NULL if no tty */
372 unsigned int locks; /* How many file locks are being held */
373 /* ipc stuff */
374 struct sem_undo *semundo;
375 struct sem_queue *semsleeping;
376 /* CPU-specific state of this task */
377 struct thread_struct thread;
378 /* filesystem information */
379 struct fs_struct *fs;
380 /* open file information */
381 struct files_struct *files;
382 /* signal handlers */
383 spinlock_t sigmask_lock; /* Protects signal and blocked */
384 struct signal_struct *sig;
385
386 sigset_t blocked;
387 struct sigpending pending;
388
389 unsigned long sas_ss_sp;
390 size_t sas_ss_size;
391 int (*notifier)(void *priv);
392 void *notifier_data;
393 sigset_t *notifier_mask;
394
395 /* TUX state */
396 void *tux_info;
397 void (*tux_exit)(void);
398
399
400 /* Thread group tracking */
401 u32 parent_exec_id;
402 u32 self_exec_id;
403 /* Protection of (de-)allocation: mm, files, fs, tty */
404 spinlock_t alloc_lock;
405 };
406
407 /*
408 * Per process flags
409 */
410 #define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
411 /* Not implemented yet, only for 486*/
412 #define PF_STARTING 0x00000002 /* being created */
413 #define PF_EXITING 0x00000004 /* getting shut down */
414 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
415 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
416 #define PF_DUMPCORE 0x00000200 /* dumped core */
417 #define PF_SIGNALED 0x00000400 /* killed by a signal */
418 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
419 #define PF_VFORK 0x00001000 /* Wake up parent in mm_release */
420
421 #define PF_USEDFPU 0x00100000 /* task used FPU this quantum (SMP) */
422 #define PF_ATOMICALLOC 0x00400000 /* process never syncs in gfp()*/
423
424 /*
425 * Ptrace flags
426 */
427
428 #define PT_PTRACED 0x00000001
429 #define PT_TRACESYS 0x00000002
430 #define PT_DTRACE 0x00000004 /* delayed trace (used on m68k, i386) */
431 #define PT_TRACESYSGOOD 0x00000008
432
433 /*
434 * Limit the stack by to some sane default: root can always
435 * increase this limit if needed.. 8MB seems reasonable.
436 */
437 #define _STK_LIM (8*1024*1024)
438
439 #define DEF_COUNTER (10*HZ/100) /* 100 ms time slice */
440 #define MAX_COUNTER (20*HZ/100)
441 #define DEF_NICE (0)
442
443 /*
444 * INIT_TASK is used to set up the first task table, touch at
445 * your own risk!. Base=0, limit=0x1fffff (=2MB)
446 */
447 #define INIT_TASK(tsk) \
448 { \
449 state: 0, \
450 flags: 0, \
451 sigpending: 0, \
452 addr_limit: KERNEL_DS, \
453 exec_domain: &default_exec_domain, \
454 lock_depth: -1, \
455 counter: DEF_COUNTER, \
456 nice: DEF_NICE, \
457 policy: SCHED_OTHER, \
458 mm: NULL, \
459 active_mm: &init_mm, \
460 cpus_allowed: -1, \
461 run_list: LIST_HEAD_INIT(tsk.run_list), \
462 next_task: &tsk, \
463 prev_task: &tsk, \
464 p_opptr: &tsk, \
465 p_pptr: &tsk, \
466 thread_group: LIST_HEAD_INIT(tsk.thread_group), \
467 wait_chldexit: __WAIT_QUEUE_HEAD_INITIALIZER(tsk.wait_chldexit),\
468 real_timer: { \
469 function: it_real_fn \
470 }, \
471 cap_effective: CAP_INIT_EFF_SET, \
472 cap_inheritable: CAP_INIT_INH_SET, \
473 cap_permitted: CAP_FULL_SET, \
474 keep_capabilities: 0, \
475 rlim: INIT_RLIMITS, \
476 user: INIT_USER, \
477 comm: "swapper", \
478 thread: INIT_THREAD, \
479 fs: &init_fs, \
480 files: &init_files, \
481 sigmask_lock: SPIN_LOCK_UNLOCKED, \
482 sig: &init_signals, \
483 pending: { NULL, &tsk.pending.head, {{0}}}, \
484 blocked: {{0}}, \
485 alloc_lock: SPIN_LOCK_UNLOCKED \
486 }
487
488
489 #ifndef INIT_TASK_SIZE
490 # define INIT_TASK_SIZE 2048*sizeof(long)
491 #endif
492
493 union task_union {
494 struct task_struct task;
495 unsigned long stack[INIT_TASK_SIZE/sizeof(long)];
496 };
497
498 extern union task_union init_task_union;
499
500 extern struct mm_struct init_mm;
501 extern struct task_struct *init_tasks[NR_CPUS];
502
503 /* PID hashing. (shouldnt this be dynamic?) */
504 #define PIDHASH_SZ (4096 >> 2)
505 extern struct task_struct *pidhash[PIDHASH_SZ];
506
507 #define pid_hashfn(x) ((((x) >> 8) ^ (x)) & (PIDHASH_SZ - 1))
508
509 static inline void hash_pid(struct task_struct *p)
510 {
511 struct task_struct **htable = &pidhash[pid_hashfn(p->pid)];
512
513 if((p->pidhash_next = *htable) != NULL)
514 (*htable)->pidhash_pprev = &p->pidhash_next;
515 *htable = p;
516 p->pidhash_pprev = htable;
517 }
518
519 static inline void unhash_pid(struct task_struct *p)
520 {
521 if(p->pidhash_next)
522 p->pidhash_next->pidhash_pprev = p->pidhash_pprev;
523 *p->pidhash_pprev = p->pidhash_next;
524 }
525
526 static inline struct task_struct *find_task_by_pid(int pid)
527 {
528 struct task_struct *p, **htable = &pidhash[pid_hashfn(pid)];
529
530 for(p = *htable; p && p->pid != pid; p = p->pidhash_next)
531 ;
532
533 return p;
534 }
535
536 /* per-UID process charging. */
537 extern struct user_struct * alloc_uid(uid_t);
538 extern void free_uid(struct user_struct *);
539
540 #include <asm/current.h>
541
542 extern unsigned long volatile jiffies;
543 extern unsigned long itimer_ticks;
544 extern unsigned long itimer_next;
545 extern struct timeval xtime;
546 extern void do_timer(struct pt_regs *);
547
548 extern unsigned int * prof_buffer;
549 extern unsigned long prof_len;
550 extern long prof_shift;
551 extern pid_t prof_pid;
552
553 #define CURRENT_TIME (xtime.tv_sec)
554
555 extern void FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr));
556 extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr));
557 extern void FASTCALL(sleep_on(wait_queue_head_t *q));
558 extern long FASTCALL(sleep_on_timeout(wait_queue_head_t *q,
559 signed long timeout));
560 extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
561 extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
562 signed long timeout));
563 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
564
565 #define wake_up(x) __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1)
566 #define wake_up_nr(x, nr) __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr)
567 #define wake_up_all(x) __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0)
568 #define wake_up_sync(x) __wake_up_sync((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1)
569 #define wake_up_sync_nr(x, nr) __wake_up_sync((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr)
570 #define wake_up_interruptible(x) __wake_up((x),TASK_INTERRUPTIBLE, 1)
571 #define wake_up_interruptible_nr(x, nr) __wake_up((x),TASK_INTERRUPTIBLE, nr)
572 #define wake_up_interruptible_all(x) __wake_up((x),TASK_INTERRUPTIBLE, 0)
573 #define wake_up_interruptible_sync(x) __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)
574 #define wake_up_interruptible_sync_nr(x) __wake_up_sync((x),TASK_INTERRUPTIBLE, nr)
575 asmlinkage long sys_wait4(pid_t pid,unsigned int * stat_addr, int options, struct rusage * ru);
576
577 extern int in_group_p(gid_t);
578 extern int in_egroup_p(gid_t);
579
580 extern void proc_caches_init(void);
581 extern void flush_signals(struct task_struct *);
582 extern void flush_signal_handlers(struct task_struct *);
583 extern int dequeue_signal(sigset_t *, siginfo_t *);
584 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
585 sigset_t *mask);
586 extern void unblock_all_signals(void);
587 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
588 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
589 extern int kill_pg_info(int, struct siginfo *, pid_t);
590 extern int kill_sl_info(int, struct siginfo *, pid_t);
591 extern int kill_proc_info(int, struct siginfo *, pid_t);
592 extern void notify_parent(struct task_struct *, int);
593 extern void do_notify_parent(struct task_struct *, int);
594 extern void force_sig(int, struct task_struct *);
595 extern int send_sig(int, struct task_struct *, int);
596 extern int kill_pg(pid_t, int, int);
597 extern int kill_sl(pid_t, int, int);
598 extern int kill_proc(pid_t, int, int);
599 extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
600 extern int do_sigaltstack(const stack_t *, stack_t *, unsigned long);
601
602 static inline int signal_pending(struct task_struct *p)
603 {
604 return (p->sigpending != 0);
605 }
606
607 /*
608 * Re-calculate pending state from the set of locally pending
609 * signals, globally pending signals, and blocked signals.
610 */
611 static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked)
612 {
613 unsigned long ready;
614 long i;
615
616 switch (_NSIG_WORDS) {
617 default:
618 for (i = _NSIG_WORDS, ready = 0; --i >= 0 ;)
619 ready |= signal->sig[i] &~ blocked->sig[i];
620 break;
621
622 case 4: ready = signal->sig[3] &~ blocked->sig[3];
623 ready |= signal->sig[2] &~ blocked->sig[2];
624 ready |= signal->sig[1] &~ blocked->sig[1];
625 ready |= signal->sig[0] &~ blocked->sig[0];
626 break;
627
628 case 2: ready = signal->sig[1] &~ blocked->sig[1];
629 ready |= signal->sig[0] &~ blocked->sig[0];
630 break;
631
632 case 1: ready = signal->sig[0] &~ blocked->sig[0];
633 }
634 return ready != 0;
635 }
636
637 /* Reevaluate whether the task has signals pending delivery.
638 This is required every time the blocked sigset_t changes.
639 All callers should have t->sigmask_lock. */
640
641 static inline void recalc_sigpending(struct task_struct *t)
642 {
643 t->sigpending = has_pending_signals(&t->pending.signal, &t->blocked);
644 }
645
646 /* True if we are on the alternate signal stack. */
647
648 static inline int on_sig_stack(unsigned long sp)
649 {
650 return (sp - current->sas_ss_sp < current->sas_ss_size);
651 }
652
653 static inline int sas_ss_flags(unsigned long sp)
654 {
655 return (current->sas_ss_size == 0 ? SS_DISABLE
656 : on_sig_stack(sp) ? SS_ONSTACK : 0);
657 }
658
659 extern int request_irq(unsigned int,
660 void (*handler)(int, void *, struct pt_regs *),
661 unsigned long, const char *, void *);
662 extern void free_irq(unsigned int, void *);
663
664 /*
665 * This has now become a routine instead of a macro, it sets a flag if
666 * it returns true (to do BSD-style accounting where the process is flagged
667 * if it uses root privs). The implication of this is that you should do
668 * normal permissions checks first, and check suser() last.
669 *
670 * [Dec 1997 -- Chris Evans]
671 * For correctness, the above considerations need to be extended to
672 * fsuser(). This is done, along with moving fsuser() checks to be
673 * last.
674 *
675 * These will be removed, but in the mean time, when the SECURE_NOROOT
676 * flag is set, uids don't grant privilege.
677 */
678 static inline int suser(void)
679 {
680 if (!issecure(SECURE_NOROOT) && current->euid == 0) {
681 current->flags |= PF_SUPERPRIV;
682 return 1;
683 }
684 return 0;
685 }
686
687 static inline int fsuser(void)
688 {
689 if (!issecure(SECURE_NOROOT) && current->fsuid == 0) {
690 current->flags |= PF_SUPERPRIV;
691 return 1;
692 }
693 return 0;
694 }
695
696 /*
697 * capable() checks for a particular capability.
698 * New privilege checks should use this interface, rather than suser() or
699 * fsuser(). See include/linux/capability.h for defined capabilities.
700 */
701
702 static inline int capable(int cap)
703 {
704 #if 1 /* ok now */
705 if (cap_raised(current->cap_effective, cap))
706 #else
707 if (cap_is_fs_cap(cap) ? current->fsuid == 0 : current->euid == 0)
708 #endif
709 {
710 current->flags |= PF_SUPERPRIV;
711 return 1;
712 }
713 return 0;
714 }
715
716 /*
717 * Routines for handling mm_structs
718 */
719 extern struct mm_struct * mm_alloc(void);
720
721 extern struct mm_struct * start_lazy_tlb(void);
722 extern void end_lazy_tlb(struct mm_struct *mm);
723
724 /* mmdrop drops the mm and the page tables */
725 extern inline void FASTCALL(__mmdrop(struct mm_struct *));
726 static inline void mmdrop(struct mm_struct * mm)
727 {
728 if (atomic_dec_and_test(&mm->mm_count))
729 __mmdrop(mm);
730 }
731
732 /* mmput gets rid of the mappings and all user-space */
733 extern void mmput(struct mm_struct *);
734 /* Remove the current tasks stale references to the old mm_struct */
735 extern void mm_release(void);
736
737 /*
738 * Routines for handling the fd arrays
739 */
740 extern struct file ** alloc_fd_array(int);
741 extern int expand_fd_array(struct files_struct *, int nr);
742 extern void free_fd_array(struct file **, int);
743
744 extern fd_set *alloc_fdset(int);
745 extern int expand_fdset(struct files_struct *, int nr);
746 extern void free_fdset(fd_set *, int);
747
748 extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
749 extern void flush_thread(void);
750 extern void exit_thread(void);
751
752 extern void exit_mm(struct task_struct *);
753 extern void exit_files(struct task_struct *);
754 extern void exit_sighand(struct task_struct *);
755
756 extern void daemonize(void);
757
758 extern int do_execve(char *, char **, char **, struct pt_regs *);
759 extern int do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long);
760
761 extern void FASTCALL(add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
762 extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait));
763 extern void FASTCALL(remove_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
764
765 #define __wait_event(wq, condition) \
766 do { \
767 wait_queue_t __wait; \
768 init_waitqueue_entry(&__wait, current); \
769 \
770 add_wait_queue(&wq, &__wait); \
771 for (;;) { \
772 set_current_state(TASK_UNINTERRUPTIBLE); \
773 if (condition) \
774 break; \
775 schedule(); \
776 } \
777 current->state = TASK_RUNNING; \
778 remove_wait_queue(&wq, &__wait); \
779 } while (0)
780
781 #define wait_event(wq, condition) \
782 do { \
783 if (condition) \
784 break; \
785 __wait_event(wq, condition); \
786 } while (0)
787
788 #define __wait_event_interruptible(wq, condition, ret) \
789 do { \
790 wait_queue_t __wait; \
791 init_waitqueue_entry(&__wait, current); \
792 \
793 add_wait_queue(&wq, &__wait); \
794 for (;;) { \
795 set_current_state(TASK_INTERRUPTIBLE); \
796 if (condition) \
797 break; \
798 if (!signal_pending(current)) { \
799 schedule(); \
800 continue; \
801 } \
802 ret = -ERESTARTSYS; \
803 break; \
804 } \
805 current->state = TASK_RUNNING; \
806 remove_wait_queue(&wq, &__wait); \
807 } while (0)
808
809 #define wait_event_interruptible(wq, condition) \
810 ({ \
811 int __ret = 0; \
812 if (!(condition)) \
813 __wait_event_interruptible(wq, condition, __ret); \
814 __ret; \
815 })
816
817 #define REMOVE_LINKS(p) do { \
818 (p)->next_task->prev_task = (p)->prev_task; \
819 (p)->prev_task->next_task = (p)->next_task; \
820 if ((p)->p_osptr) \
821 (p)->p_osptr->p_ysptr = (p)->p_ysptr; \
822 if ((p)->p_ysptr) \
823 (p)->p_ysptr->p_osptr = (p)->p_osptr; \
824 else \
825 (p)->p_pptr->p_cptr = (p)->p_osptr; \
826 } while (0)
827
828 #define SET_LINKS(p) do { \
829 (p)->next_task = &init_task; \
830 (p)->prev_task = init_task.prev_task; \
831 init_task.prev_task->next_task = (p); \
832 init_task.prev_task = (p); \
833 (p)->p_ysptr = NULL; \
834 if (((p)->p_osptr = (p)->p_pptr->p_cptr) != NULL) \
835 (p)->p_osptr->p_ysptr = p; \
836 (p)->p_pptr->p_cptr = p; \
837 } while (0)
838
839 #define for_each_task(p) \
840 for (p = &init_task ; (p = p->next_task) != &init_task ; )
841
842 #define next_thread(p) \
843 list_entry((p)->thread_group.next, struct task_struct, thread_group)
844
845 static inline void del_from_runqueue(struct task_struct * p)
846 {
847 nr_running--;
848 p->sleep_time = jiffies;
849 list_del(&p->run_list);
850 p->run_list.next = NULL;
851 }
852
853 static inline int task_on_runqueue(struct task_struct *p)
854 {
855 return (p->run_list.next != NULL);
856 }
857
858 static inline void unhash_process(struct task_struct *p)
859 {
860 if (task_on_runqueue(p)) BUG();
861 write_lock_irq(&tasklist_lock);
862 nr_threads--;
863 unhash_pid(p);
864 REMOVE_LINKS(p);
865 list_del(&p->thread_group);
866 write_unlock_irq(&tasklist_lock);
867 }
868
869 static inline void task_lock(struct task_struct *p)
870 {
871 spin_lock(&p->alloc_lock);
872 }
873
874 static inline void task_unlock(struct task_struct *p)
875 {
876 spin_unlock(&p->alloc_lock);
877 }
878
879 /* write full pathname into buffer and return start of pathname */
880 static inline char * d_path(struct dentry *dentry, struct vfsmount *vfsmnt,
881 char *buf, int buflen)
882 {
883 char *res;
884 struct vfsmount *rootmnt;
885 struct dentry *root;
886 read_lock(¤t->fs->lock);
887 rootmnt = mntget(current->fs->rootmnt);
888 root = dget(current->fs->root);
889 read_unlock(¤t->fs->lock);
890 spin_lock(&dcache_lock);
891 res = __d_path(dentry, vfsmnt, root, rootmnt, buf, buflen);
892 spin_unlock(&dcache_lock);
893 dput(root);
894 mntput(rootmnt);
895 return res;
896 }
897
898 #endif /* __KERNEL__ */
899
900 #endif
901