1 /* interrupt.h */ 2 #ifndef _LINUX_INTERRUPT_H 3 #define _LINUX_INTERRUPT_H 4 5 #include <linux/kernel.h> 6 #include <linux/linkage.h> 7 #include <linux/bitops.h> 8 #include <linux/preempt.h> 9 #include <linux/cpumask.h> 10 #include <linux/irqreturn.h> 11 #include <linux/irqnr.h> 12 #include <linux/hardirq.h> 13 #include <linux/irqflags.h> 14 #include <linux/smp.h> 15 #include <linux/percpu.h> 16 #include <linux/hrtimer.h> 17 #include <linux/kref.h> 18 #include <linux/workqueue.h> 19 20 #include <linux/atomic.h> 21 #include <asm/ptrace.h> 22 23 /* 24 * These correspond to the IORESOURCE_IRQ_* defines in 25 * linux/ioport.h to select the interrupt line behaviour. When 26 * requesting an interrupt without specifying a IRQF_TRIGGER, the 27 * setting should be assumed to be "as already configured", which 28 * may be as per machine or firmware initialisation. 29 */ 30 #define IRQF_TRIGGER_NONE 0x00000000 31 #define IRQF_TRIGGER_RISING 0x00000001 32 #define IRQF_TRIGGER_FALLING 0x00000002 33 #define IRQF_TRIGGER_HIGH 0x00000004 34 #define IRQF_TRIGGER_LOW 0x00000008 35 #define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \ 36 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING) 37 #define IRQF_TRIGGER_PROBE 0x00000010 38 39 /* 40 * These flags used only by the kernel as part of the 41 * irq handling routines. 42 * 43 * IRQF_DISABLED - keep irqs disabled when calling the action handler. 44 * DEPRECATED. This flag is a NOOP and scheduled to be removed 45 * IRQF_SHARED - allow sharing the irq among several devices 46 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur 47 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt 48 * IRQF_PERCPU - Interrupt is per cpu 49 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing 50 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is 51 * registered first in an shared interrupt is considered for 52 * performance reasons) 53 * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished. 54 * Used by threaded interrupts which need to keep the 55 * irq line disabled until the threaded handler has been run. 56 * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend 57 * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set 58 * IRQF_NO_THREAD - Interrupt cannot be threaded 59 * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device 60 * resume time. 61 */ 62 #define IRQF_DISABLED 0x00000020 63 #define IRQF_SHARED 0x00000080 64 #define IRQF_PROBE_SHARED 0x00000100 65 #define __IRQF_TIMER 0x00000200 66 #define IRQF_PERCPU 0x00000400 67 #define IRQF_NOBALANCING 0x00000800 68 #define IRQF_IRQPOLL 0x00001000 69 #define IRQF_ONESHOT 0x00002000 70 #define IRQF_NO_SUSPEND 0x00004000 71 #define IRQF_FORCE_RESUME 0x00008000 72 #define IRQF_NO_THREAD 0x00010000 73 #define IRQF_EARLY_RESUME 0x00020000 74 75 #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD) 76 77 /* 78 * These values can be returned by request_any_context_irq() and 79 * describe the context the interrupt will be run in. 80 * 81 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context 82 * IRQC_IS_NESTED - interrupt runs in a nested threaded context 83 */ 84 enum { 85 IRQC_IS_HARDIRQ = 0, 86 IRQC_IS_NESTED, 87 }; 88 89 typedef irqreturn_t (*irq_handler_t)(int, void *); 90 91 /** 92 * struct irqaction - per interrupt action descriptor 93 * @handler: interrupt handler function 94 * @name: name of the device 95 * @dev_id: cookie to identify the device 96 * @percpu_dev_id: cookie to identify the device 97 * @next: pointer to the next irqaction for shared interrupts 98 * @irq: interrupt number 99 * @flags: flags (see IRQF_* above) 100 * @thread_fn: interrupt handler function for threaded interrupts 101 * @thread: thread pointer for threaded interrupts 102 * @thread_flags: flags related to @thread 103 * @thread_mask: bitmask for keeping track of @thread activity 104 * @dir: pointer to the proc/irq/NN/name entry 105 */ 106 struct irqaction { 107 irq_handler_t handler; 108 void *dev_id; 109 void __percpu *percpu_dev_id; 110 struct irqaction *next; 111 irq_handler_t thread_fn; 112 struct task_struct *thread; 113 unsigned int irq; 114 unsigned int flags; 115 unsigned long thread_flags; 116 unsigned long thread_mask; 117 const char *name; 118 struct proc_dir_entry *dir; 119 } ____cacheline_internodealigned_in_smp; 120 121 extern irqreturn_t no_action(int cpl, void *dev_id); 122 123 extern int __must_check 124 request_threaded_irq(unsigned int irq, irq_handler_t handler, 125 irq_handler_t thread_fn, 126 unsigned long flags, const char *name, void *dev); 127 128 static inline int __must_check 129 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags, 130 const char *name, void *dev) 131 { 132 return request_threaded_irq(irq, handler, NULL, flags, name, dev); 133 } 134 135 extern int __must_check 136 request_any_context_irq(unsigned int irq, irq_handler_t handler, 137 unsigned long flags, const char *name, void *dev_id); 138 139 extern int __must_check 140 request_percpu_irq(unsigned int irq, irq_handler_t handler, 141 const char *devname, void __percpu *percpu_dev_id); 142 143 extern void free_irq(unsigned int, void *); 144 extern void free_percpu_irq(unsigned int, void __percpu *); 145 146 struct device; 147 148 extern int __must_check 149 devm_request_threaded_irq(struct device *dev, unsigned int irq, 150 irq_handler_t handler, irq_handler_t thread_fn, 151 unsigned long irqflags, const char *devname, 152 void *dev_id); 153 154 static inline int __must_check 155 devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler, 156 unsigned long irqflags, const char *devname, void *dev_id) 157 { 158 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags, 159 devname, dev_id); 160 } 161 162 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id); 163 164 /* 165 * On lockdep we dont want to enable hardirqs in hardirq 166 * context. Use local_irq_enable_in_hardirq() to annotate 167 * kernel code that has to do this nevertheless (pretty much 168 * the only valid case is for old/broken hardware that is 169 * insanely slow). 170 * 171 * NOTE: in theory this might break fragile code that relies 172 * on hardirq delivery - in practice we dont seem to have such 173 * places left. So the only effect should be slightly increased 174 * irqs-off latencies. 175 */ 176 #ifdef CONFIG_LOCKDEP 177 # define local_irq_enable_in_hardirq() do { } while (0) 178 #else 179 # define local_irq_enable_in_hardirq() local_irq_enable() 180 #endif 181 182 extern void disable_irq_nosync(unsigned int irq); 183 extern void disable_irq(unsigned int irq); 184 extern void disable_percpu_irq(unsigned int irq); 185 extern void enable_irq(unsigned int irq); 186 extern void enable_percpu_irq(unsigned int irq, unsigned int type); 187 188 /* The following three functions are for the core kernel use only. */ 189 extern void suspend_device_irqs(void); 190 extern void resume_device_irqs(void); 191 #ifdef CONFIG_PM_SLEEP 192 extern int check_wakeup_irqs(void); 193 #else 194 static inline int check_wakeup_irqs(void) { return 0; } 195 #endif 196 197 #if defined(CONFIG_SMP) 198 199 extern cpumask_var_t irq_default_affinity; 200 201 extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask); 202 extern int irq_can_set_affinity(unsigned int irq); 203 extern int irq_select_affinity(unsigned int irq); 204 205 extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m); 206 207 /** 208 * struct irq_affinity_notify - context for notification of IRQ affinity changes 209 * @irq: Interrupt to which notification applies 210 * @kref: Reference count, for internal use 211 * @work: Work item, for internal use 212 * @notify: Function to be called on change. This will be 213 * called in process context. 214 * @release: Function to be called on release. This will be 215 * called in process context. Once registered, the 216 * structure must only be freed when this function is 217 * called or later. 218 */ 219 struct irq_affinity_notify { 220 unsigned int irq; 221 struct kref kref; 222 struct work_struct work; 223 void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); 224 void (*release)(struct kref *ref); 225 }; 226 227 extern int 228 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify); 229 230 #else /* CONFIG_SMP */ 231 232 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m) 233 { 234 return -EINVAL; 235 } 236 237 static inline int irq_can_set_affinity(unsigned int irq) 238 { 239 return 0; 240 } 241 242 static inline int irq_select_affinity(unsigned int irq) { return 0; } 243 244 static inline int irq_set_affinity_hint(unsigned int irq, 245 const struct cpumask *m) 246 { 247 return -EINVAL; 248 } 249 #endif /* CONFIG_SMP */ 250 251 /* 252 * Special lockdep variants of irq disabling/enabling. 253 * These should be used for locking constructs that 254 * know that a particular irq context which is disabled, 255 * and which is the only irq-context user of a lock, 256 * that it's safe to take the lock in the irq-disabled 257 * section without disabling hardirqs. 258 * 259 * On !CONFIG_LOCKDEP they are equivalent to the normal 260 * irq disable/enable methods. 261 */ 262 static inline void disable_irq_nosync_lockdep(unsigned int irq) 263 { 264 disable_irq_nosync(irq); 265 #ifdef CONFIG_LOCKDEP 266 local_irq_disable(); 267 #endif 268 } 269 270 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags) 271 { 272 disable_irq_nosync(irq); 273 #ifdef CONFIG_LOCKDEP 274 local_irq_save(*flags); 275 #endif 276 } 277 278 static inline void disable_irq_lockdep(unsigned int irq) 279 { 280 disable_irq(irq); 281 #ifdef CONFIG_LOCKDEP 282 local_irq_disable(); 283 #endif 284 } 285 286 static inline void enable_irq_lockdep(unsigned int irq) 287 { 288 #ifdef CONFIG_LOCKDEP 289 local_irq_enable(); 290 #endif 291 enable_irq(irq); 292 } 293 294 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags) 295 { 296 #ifdef CONFIG_LOCKDEP 297 local_irq_restore(*flags); 298 #endif 299 enable_irq(irq); 300 } 301 302 /* IRQ wakeup (PM) control: */ 303 extern int irq_set_irq_wake(unsigned int irq, unsigned int on); 304 305 static inline int enable_irq_wake(unsigned int irq) 306 { 307 return irq_set_irq_wake(irq, 1); 308 } 309 310 static inline int disable_irq_wake(unsigned int irq) 311 { 312 return irq_set_irq_wake(irq, 0); 313 } 314 315 316 #ifdef CONFIG_IRQ_FORCED_THREADING 317 extern bool force_irqthreads; 318 #else 319 #define force_irqthreads (0) 320 #endif 321 322 #ifndef __ARCH_SET_SOFTIRQ_PENDING 323 #define set_softirq_pending(x) (local_softirq_pending() = (x)) 324 #define or_softirq_pending(x) (local_softirq_pending() |= (x)) 325 #endif 326 327 /* Some architectures might implement lazy enabling/disabling of 328 * interrupts. In some cases, such as stop_machine, we might want 329 * to ensure that after a local_irq_disable(), interrupts have 330 * really been disabled in hardware. Such architectures need to 331 * implement the following hook. 332 */ 333 #ifndef hard_irq_disable 334 #define hard_irq_disable() do { } while(0) 335 #endif 336 337 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high 338 frequency threaded job scheduling. For almost all the purposes 339 tasklets are more than enough. F.e. all serial device BHs et 340 al. should be converted to tasklets, not to softirqs. 341 */ 342 343 enum 344 { 345 HI_SOFTIRQ=0, 346 TIMER_SOFTIRQ, 347 NET_TX_SOFTIRQ, 348 NET_RX_SOFTIRQ, 349 BLOCK_SOFTIRQ, 350 BLOCK_IOPOLL_SOFTIRQ, 351 TASKLET_SOFTIRQ, 352 SCHED_SOFTIRQ, 353 HRTIMER_SOFTIRQ, 354 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */ 355 356 NR_SOFTIRQS 357 }; 358 359 #define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ)) 360 361 /* map softirq index to softirq name. update 'softirq_to_name' in 362 * kernel/softirq.c when adding a new softirq. 363 */ 364 extern char *softirq_to_name[NR_SOFTIRQS]; 365 366 /* softirq mask and active fields moved to irq_cpustat_t in 367 * asm/hardirq.h to get better cache usage. KAO 368 */ 369 370 struct softirq_action 371 { 372 void (*action)(struct softirq_action *); 373 }; 374 375 asmlinkage void do_softirq(void); 376 asmlinkage void __do_softirq(void); 377 extern void open_softirq(int nr, void (*action)(struct softirq_action *)); 378 extern void softirq_init(void); 379 extern void __raise_softirq_irqoff(unsigned int nr); 380 381 extern void raise_softirq_irqoff(unsigned int nr); 382 extern void raise_softirq(unsigned int nr); 383 384 /* This is the worklist that queues up per-cpu softirq work. 385 * 386 * send_remote_sendirq() adds work to these lists, and 387 * the softirq handler itself dequeues from them. The queues 388 * are protected by disabling local cpu interrupts and they must 389 * only be accessed by the local cpu that they are for. 390 */ 391 DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list); 392 393 DECLARE_PER_CPU(struct task_struct *, ksoftirqd); 394 395 static inline struct task_struct *this_cpu_ksoftirqd(void) 396 { 397 return this_cpu_read(ksoftirqd); 398 } 399 400 /* Try to send a softirq to a remote cpu. If this cannot be done, the 401 * work will be queued to the local cpu. 402 */ 403 extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq); 404 405 /* Like send_remote_softirq(), but the caller must disable local cpu interrupts 406 * and compute the current cpu, passed in as 'this_cpu'. 407 */ 408 extern void __send_remote_softirq(struct call_single_data *cp, int cpu, 409 int this_cpu, int softirq); 410 411 /* Tasklets --- multithreaded analogue of BHs. 412 413 Main feature differing them of generic softirqs: tasklet 414 is running only on one CPU simultaneously. 415 416 Main feature differing them of BHs: different tasklets 417 may be run simultaneously on different CPUs. 418 419 Properties: 420 * If tasklet_schedule() is called, then tasklet is guaranteed 421 to be executed on some cpu at least once after this. 422 * If the tasklet is already scheduled, but its execution is still not 423 started, it will be executed only once. 424 * If this tasklet is already running on another CPU (or schedule is called 425 from tasklet itself), it is rescheduled for later. 426 * Tasklet is strictly serialized wrt itself, but not 427 wrt another tasklets. If client needs some intertask synchronization, 428 he makes it with spinlocks. 429 */ 430 431 struct tasklet_struct 432 { 433 struct tasklet_struct *next; 434 unsigned long state; 435 atomic_t count; 436 void (*func)(unsigned long); 437 unsigned long data; 438 }; 439 440 #define DECLARE_TASKLET(name, func, data) \ 441 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data } 442 443 #define DECLARE_TASKLET_DISABLED(name, func, data) \ 444 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } 445 446 447 enum 448 { 449 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ 450 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ 451 }; 452 453 #ifdef CONFIG_SMP 454 static inline int tasklet_trylock(struct tasklet_struct *t) 455 { 456 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); 457 } 458 459 static inline void tasklet_unlock(struct tasklet_struct *t) 460 { 461 smp_mb__before_clear_bit(); 462 clear_bit(TASKLET_STATE_RUN, &(t)->state); 463 } 464 465 static inline void tasklet_unlock_wait(struct tasklet_struct *t) 466 { 467 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } 468 } 469 #else 470 #define tasklet_trylock(t) 1 471 #define tasklet_unlock_wait(t) do { } while (0) 472 #define tasklet_unlock(t) do { } while (0) 473 #endif 474 475 extern void __tasklet_schedule(struct tasklet_struct *t); 476 477 static inline void tasklet_schedule(struct tasklet_struct *t) 478 { 479 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 480 __tasklet_schedule(t); 481 } 482 483 extern void __tasklet_hi_schedule(struct tasklet_struct *t); 484 485 static inline void tasklet_hi_schedule(struct tasklet_struct *t) 486 { 487 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 488 __tasklet_hi_schedule(t); 489 } 490 491 extern void __tasklet_hi_schedule_first(struct tasklet_struct *t); 492 493 /* 494 * This version avoids touching any other tasklets. Needed for kmemcheck 495 * in order not to take any page faults while enqueueing this tasklet; 496 * consider VERY carefully whether you really need this or 497 * tasklet_hi_schedule()... 498 */ 499 static inline void tasklet_hi_schedule_first(struct tasklet_struct *t) 500 { 501 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 502 __tasklet_hi_schedule_first(t); 503 } 504 505 506 static inline void tasklet_disable_nosync(struct tasklet_struct *t) 507 { 508 atomic_inc(&t->count); 509 smp_mb__after_atomic_inc(); 510 } 511 512 static inline void tasklet_disable(struct tasklet_struct *t) 513 { 514 tasklet_disable_nosync(t); 515 tasklet_unlock_wait(t); 516 smp_mb(); 517 } 518 519 static inline void tasklet_enable(struct tasklet_struct *t) 520 { 521 smp_mb__before_atomic_dec(); 522 atomic_dec(&t->count); 523 } 524 525 static inline void tasklet_hi_enable(struct tasklet_struct *t) 526 { 527 smp_mb__before_atomic_dec(); 528 atomic_dec(&t->count); 529 } 530 531 extern void tasklet_kill(struct tasklet_struct *t); 532 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); 533 extern void tasklet_init(struct tasklet_struct *t, 534 void (*func)(unsigned long), unsigned long data); 535 536 struct tasklet_hrtimer { 537 struct hrtimer timer; 538 struct tasklet_struct tasklet; 539 enum hrtimer_restart (*function)(struct hrtimer *); 540 }; 541 542 extern void 543 tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer, 544 enum hrtimer_restart (*function)(struct hrtimer *), 545 clockid_t which_clock, enum hrtimer_mode mode); 546 547 static inline 548 int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time, 549 const enum hrtimer_mode mode) 550 { 551 return hrtimer_start(&ttimer->timer, time, mode); 552 } 553 554 static inline 555 void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer) 556 { 557 hrtimer_cancel(&ttimer->timer); 558 tasklet_kill(&ttimer->tasklet); 559 } 560 561 /* 562 * Autoprobing for irqs: 563 * 564 * probe_irq_on() and probe_irq_off() provide robust primitives 565 * for accurate IRQ probing during kernel initialization. They are 566 * reasonably simple to use, are not "fooled" by spurious interrupts, 567 * and, unlike other attempts at IRQ probing, they do not get hung on 568 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards). 569 * 570 * For reasonably foolproof probing, use them as follows: 571 * 572 * 1. clear and/or mask the device's internal interrupt. 573 * 2. sti(); 574 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs 575 * 4. enable the device and cause it to trigger an interrupt. 576 * 5. wait for the device to interrupt, using non-intrusive polling or a delay. 577 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple 578 * 7. service the device to clear its pending interrupt. 579 * 8. loop again if paranoia is required. 580 * 581 * probe_irq_on() returns a mask of allocated irq's. 582 * 583 * probe_irq_off() takes the mask as a parameter, 584 * and returns the irq number which occurred, 585 * or zero if none occurred, or a negative irq number 586 * if more than one irq occurred. 587 */ 588 589 #if !defined(CONFIG_GENERIC_IRQ_PROBE) 590 static inline unsigned long probe_irq_on(void) 591 { 592 return 0; 593 } 594 static inline int probe_irq_off(unsigned long val) 595 { 596 return 0; 597 } 598 static inline unsigned int probe_irq_mask(unsigned long val) 599 { 600 return 0; 601 } 602 #else 603 extern unsigned long probe_irq_on(void); /* returns 0 on failure */ 604 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */ 605 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */ 606 #endif 607 608 #ifdef CONFIG_PROC_FS 609 /* Initialize /proc/irq/ */ 610 extern void init_irq_proc(void); 611 #else 612 static inline void init_irq_proc(void) 613 { 614 } 615 #endif 616 617 struct seq_file; 618 int show_interrupts(struct seq_file *p, void *v); 619 int arch_show_interrupts(struct seq_file *p, int prec); 620 621 extern int early_irq_init(void); 622 extern int arch_probe_nr_irqs(void); 623 extern int arch_early_irq_init(void); 624 625 #endif 626