2 * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 * Derived (i.e. mostly copied) from arch/i386/kernel/irq.c:
5 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
8 #include "linux/config.h"
9 #include "linux/kernel.h"
10 #include "linux/module.h"
11 #include "linux/smp.h"
12 #include "linux/kernel_stat.h"
13 #include "linux/interrupt.h"
14 #include "linux/random.h"
15 #include "linux/slab.h"
16 #include "linux/file.h"
17 #include "linux/proc_fs.h"
18 #include "linux/init.h"
19 #include "linux/seq_file.h"
20 #include "linux/profile.h"
21 #include "linux/hardirq.h"
23 #include "asm/hw_irq.h"
24 #include "asm/atomic.h"
25 #include "asm/signal.h"
26 #include "asm/system.h"
27 #include "asm/errno.h"
28 #include "asm/uaccess.h"
29 #include "user_util.h"
30 #include "kern_util.h"
35 #include "misc_constants.h"
38 * Generic, controller-independent functions:
41 int show_interrupts(struct seq_file *p, void *v)
43 int i = *(loff_t *) v, j;
44 struct irqaction * action;
49 for_each_online_cpu(j)
50 seq_printf(p, "CPU%d ",j);
55 spin_lock_irqsave(&irq_desc[i].lock, flags);
56 action = irq_desc[i].action;
59 seq_printf(p, "%3d: ",i);
61 seq_printf(p, "%10u ", kstat_irqs(i));
63 for_each_online_cpu(j)
64 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
66 seq_printf(p, " %14s", irq_desc[i].chip->typename);
67 seq_printf(p, " %s", action->name);
69 for (action=action->next; action; action = action->next)
70 seq_printf(p, ", %s", action->name);
74 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
75 } else if (i == NR_IRQS) {
82 struct irq_fd *active_fds = NULL;
83 static struct irq_fd **last_irq_ptr = &active_fds;
85 extern void free_irqs(void);
87 void sigio_handler(int sig, union uml_pt_regs *regs)
89 struct irq_fd *irq_fd;
92 if (smp_sigio_handler())
96 n = os_waiting_for_events(active_fds);
98 if(n == -EINTR) continue;
102 for (irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next) {
103 if (irq_fd->current_events != 0) {
104 irq_fd->current_events = 0;
105 do_IRQ(irq_fd->irq, regs);
113 static DEFINE_SPINLOCK(irq_lock);
115 int activate_fd(int irq, int fd, int type, void *dev_id)
117 struct pollfd *tmp_pfd;
118 struct irq_fd *new_fd, *irq_fd;
120 int pid, events, err, n;
123 err = os_set_fd_async(fd, pid);
127 new_fd = um_kmalloc(sizeof(*new_fd));
132 if (type == IRQ_READ)
133 events = UM_POLLIN | UM_POLLPRI;
136 *new_fd = ((struct irq_fd) { .next = NULL,
143 .current_events = 0 } );
145 /* Critical section - locked by a spinlock because this stuff can
146 * be changed from interrupt handlers. The stuff above is done
147 * outside the lock because it allocates memory.
150 /* Actually, it only looks like it can be called from interrupt
151 * context. The culprit is reactivate_fd, which calls
152 * maybe_sigio_broken, which calls write_sigio_workaround,
153 * which calls activate_fd. However, write_sigio_workaround should
154 * only be called once, at boot time. That would make it clear that
155 * this is called only from process context, and can be locked with
158 spin_lock_irqsave(&irq_lock, flags);
159 for (irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next) {
160 if ((irq_fd->fd == fd) && (irq_fd->type == type)) {
161 printk("Registering fd %d twice\n", fd);
162 printk("Irqs : %d, %d\n", irq_fd->irq, irq);
163 printk("Ids : 0x%p, 0x%p\n", irq_fd->id, dev_id);
169 if (type == IRQ_WRITE)
176 n = os_create_pollfd(fd, events, tmp_pfd, n);
181 * It means we couldn't put new pollfd to current pollfds
182 * and tmp_fds is NULL or too small for new pollfds array.
183 * Needed size is equal to n as minimum.
185 * Here we have to drop the lock in order to call
186 * kmalloc, which might sleep.
187 * If something else came in and changed the pollfds array
188 * so we will not be able to put new pollfd struct to pollfds
189 * then we free the buffer tmp_fds and try again.
191 spin_unlock_irqrestore(&irq_lock, flags);
195 tmp_pfd = um_kmalloc(n);
199 spin_lock_irqsave(&irq_lock, flags);
203 *last_irq_ptr = new_fd;
204 last_irq_ptr = &new_fd->next;
206 spin_unlock_irqrestore(&irq_lock, flags);
208 /* This calls activate_fd, so it has to be outside the critical
211 maybe_sigio_broken(fd, (type == IRQ_READ));
216 spin_unlock_irqrestore(&irq_lock, flags);
223 static void free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg)
227 spin_lock_irqsave(&irq_lock, flags);
228 os_free_irq_by_cb(test, arg, active_fds, &last_irq_ptr);
229 spin_unlock_irqrestore(&irq_lock, flags);
237 static int same_irq_and_dev(struct irq_fd *irq, void *d)
239 struct irq_and_dev *data = d;
241 return ((irq->irq == data->irq) && (irq->id == data->dev));
244 void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
246 struct irq_and_dev data = ((struct irq_and_dev) { .irq = irq,
249 free_irq_by_cb(same_irq_and_dev, &data);
252 static int same_fd(struct irq_fd *irq, void *fd)
254 return (irq->fd == *((int *)fd));
257 void free_irq_by_fd(int fd)
259 free_irq_by_cb(same_fd, &fd);
262 static struct irq_fd *find_irq_by_fd(int fd, int irqnum, int *index_out)
268 for (irq = active_fds; irq != NULL; irq = irq->next) {
269 if ((irq->fd == fd) && (irq->irq == irqnum))
274 printk("find_irq_by_fd doesn't have descriptor %d\n", fd);
277 fdi = os_get_pollfd(i);
278 if ((fdi != -1) && (fdi != fd)) {
279 printk("find_irq_by_fd - mismatch between active_fds and "
280 "pollfds, fd %d vs %d, need %d\n", irq->fd,
290 void reactivate_fd(int fd, int irqnum)
296 spin_lock_irqsave(&irq_lock, flags);
297 irq = find_irq_by_fd(fd, irqnum, &i);
299 spin_unlock_irqrestore(&irq_lock, flags);
302 os_set_pollfd(i, irq->fd);
303 spin_unlock_irqrestore(&irq_lock, flags);
305 /* This calls activate_fd, so it has to be outside the critical
308 maybe_sigio_broken(fd, (irq->type == IRQ_READ));
311 void deactivate_fd(int fd, int irqnum)
317 spin_lock_irqsave(&irq_lock, flags);
318 irq = find_irq_by_fd(fd, irqnum, &i);
321 os_set_pollfd(i, -1);
323 spin_unlock_irqrestore(&irq_lock, flags);
326 int deactivate_all_fds(void)
331 for (irq = active_fds; irq != NULL; irq = irq->next) {
332 err = os_clear_fd_async(irq->fd);
336 /* If there is a signal already queued, after unblocking ignore it */
342 #ifdef CONFIG_MODE_TT
343 void forward_interrupts(int pid)
349 spin_lock_irqsave(&irq_lock, flags);
350 for (irq = active_fds; irq != NULL; irq = irq->next) {
351 err = os_set_owner(irq->fd, pid);
353 /* XXX Just remove the irq rather than
354 * print out an infinite stream of these
356 printk("Failed to forward %d to pid %d, err = %d\n",
362 spin_unlock_irqrestore(&irq_lock, flags);
367 * do_IRQ handles all normal device IRQ's (the special
368 * SMP cross-CPU interrupts have their own specific
371 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
374 __do_IRQ(irq, (struct pt_regs *)regs);
379 int um_request_irq(unsigned int irq, int fd, int type,
380 irqreturn_t (*handler)(int, void *, struct pt_regs *),
381 unsigned long irqflags, const char * devname,
386 err = request_irq(irq, handler, irqflags, devname, dev_id);
391 err = activate_fd(irq, fd, type, dev_id);
394 EXPORT_SYMBOL(um_request_irq);
395 EXPORT_SYMBOL(reactivate_fd);
397 /* hw_interrupt_type must define (startup || enable) &&
398 * (shutdown || disable) && end */
399 static void dummy(unsigned int irq)
403 /* This is used for everything else than the timer. */
404 static struct hw_interrupt_type normal_irq_type = {
406 .release = free_irq_by_irq_and_dev,
413 static struct hw_interrupt_type SIGVTALRM_irq_type = {
414 .typename = "SIGVTALRM",
415 .release = free_irq_by_irq_and_dev,
416 .shutdown = dummy, /* never called */
423 void __init init_IRQ(void)
427 irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
428 irq_desc[TIMER_IRQ].action = NULL;
429 irq_desc[TIMER_IRQ].depth = 1;
430 irq_desc[TIMER_IRQ].chip = &SIGVTALRM_irq_type;
431 enable_irq(TIMER_IRQ);
432 for (i = 1; i < NR_IRQS; i++) {
433 irq_desc[i].status = IRQ_DISABLED;
434 irq_desc[i].action = NULL;
435 irq_desc[i].depth = 1;
436 irq_desc[i].chip = &normal_irq_type;
441 int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
446 err = os_pipe(fds, 1, 1);
448 printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
452 err = um_request_irq(irq, fds[0], IRQ_READ, handler,
453 IRQF_DISABLED | IRQF_SAMPLE_RANDOM, name,
454 (void *) (long) fds[0]);
456 printk("init_aio_irq - : um_request_irq failed, err = %d\n",
465 os_close_file(fds[0]);
466 os_close_file(fds[1]);