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/kernel.h"
9 #include "linux/module.h"
10 #include "linux/smp.h"
11 #include "linux/kernel_stat.h"
12 #include "linux/interrupt.h"
13 #include "linux/random.h"
14 #include "linux/slab.h"
15 #include "linux/file.h"
16 #include "linux/proc_fs.h"
17 #include "linux/init.h"
18 #include "linux/seq_file.h"
19 #include "linux/profile.h"
20 #include "linux/hardirq.h"
22 #include "asm/hw_irq.h"
23 #include "asm/atomic.h"
24 #include "asm/signal.h"
25 #include "asm/system.h"
26 #include "asm/errno.h"
27 #include "asm/uaccess.h"
28 #include "user_util.h"
29 #include "kern_util.h"
34 #include "misc_constants.h"
37 * Generic, controller-independent functions:
40 int show_interrupts(struct seq_file *p, void *v)
42 int i = *(loff_t *) v, j;
43 struct irqaction * action;
48 for_each_online_cpu(j)
49 seq_printf(p, "CPU%d ",j);
54 spin_lock_irqsave(&irq_desc[i].lock, flags);
55 action = irq_desc[i].action;
58 seq_printf(p, "%3d: ",i);
60 seq_printf(p, "%10u ", kstat_irqs(i));
62 for_each_online_cpu(j)
63 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
65 seq_printf(p, " %14s", irq_desc[i].chip->typename);
66 seq_printf(p, " %s", action->name);
68 for (action=action->next; action; action = action->next)
69 seq_printf(p, ", %s", action->name);
73 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
74 } else if (i == NR_IRQS) {
81 struct irq_fd *active_fds = NULL;
82 static struct irq_fd **last_irq_ptr = &active_fds;
84 extern void free_irqs(void);
86 void sigio_handler(int sig, union uml_pt_regs *regs)
88 struct irq_fd *irq_fd;
91 if (smp_sigio_handler())
95 n = os_waiting_for_events(active_fds);
97 if(n == -EINTR) continue;
101 for (irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next) {
102 if (irq_fd->current_events != 0) {
103 irq_fd->current_events = 0;
104 do_IRQ(irq_fd->irq, regs);
112 static DEFINE_SPINLOCK(irq_lock);
114 int activate_fd(int irq, int fd, int type, void *dev_id)
116 struct pollfd *tmp_pfd;
117 struct irq_fd *new_fd, *irq_fd;
119 int pid, events, err, n;
122 err = os_set_fd_async(fd, pid);
126 new_fd = um_kmalloc(sizeof(*new_fd));
131 if (type == IRQ_READ)
132 events = UM_POLLIN | UM_POLLPRI;
135 *new_fd = ((struct irq_fd) { .next = NULL,
142 .current_events = 0 } );
144 /* Critical section - locked by a spinlock because this stuff can
145 * be changed from interrupt handlers. The stuff above is done
146 * outside the lock because it allocates memory.
149 /* Actually, it only looks like it can be called from interrupt
150 * context. The culprit is reactivate_fd, which calls
151 * maybe_sigio_broken, which calls write_sigio_workaround,
152 * which calls activate_fd. However, write_sigio_workaround should
153 * only be called once, at boot time. That would make it clear that
154 * this is called only from process context, and can be locked with
157 spin_lock_irqsave(&irq_lock, flags);
158 for (irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next) {
159 if ((irq_fd->fd == fd) && (irq_fd->type == type)) {
160 printk("Registering fd %d twice\n", fd);
161 printk("Irqs : %d, %d\n", irq_fd->irq, irq);
162 printk("Ids : 0x%p, 0x%p\n", irq_fd->id, dev_id);
168 if (type == IRQ_WRITE)
175 n = os_create_pollfd(fd, events, tmp_pfd, n);
180 * It means we couldn't put new pollfd to current pollfds
181 * and tmp_fds is NULL or too small for new pollfds array.
182 * Needed size is equal to n as minimum.
184 * Here we have to drop the lock in order to call
185 * kmalloc, which might sleep.
186 * If something else came in and changed the pollfds array
187 * so we will not be able to put new pollfd struct to pollfds
188 * then we free the buffer tmp_fds and try again.
190 spin_unlock_irqrestore(&irq_lock, flags);
194 tmp_pfd = um_kmalloc(n);
198 spin_lock_irqsave(&irq_lock, flags);
202 *last_irq_ptr = new_fd;
203 last_irq_ptr = &new_fd->next;
205 spin_unlock_irqrestore(&irq_lock, flags);
207 /* This calls activate_fd, so it has to be outside the critical
210 maybe_sigio_broken(fd, (type == IRQ_READ));
215 spin_unlock_irqrestore(&irq_lock, flags);
222 static void free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg)
226 spin_lock_irqsave(&irq_lock, flags);
227 os_free_irq_by_cb(test, arg, active_fds, &last_irq_ptr);
228 spin_unlock_irqrestore(&irq_lock, flags);
236 static int same_irq_and_dev(struct irq_fd *irq, void *d)
238 struct irq_and_dev *data = d;
240 return ((irq->irq == data->irq) && (irq->id == data->dev));
243 void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
245 struct irq_and_dev data = ((struct irq_and_dev) { .irq = irq,
248 free_irq_by_cb(same_irq_and_dev, &data);
251 static int same_fd(struct irq_fd *irq, void *fd)
253 return (irq->fd == *((int *)fd));
256 void free_irq_by_fd(int fd)
258 free_irq_by_cb(same_fd, &fd);
261 static struct irq_fd *find_irq_by_fd(int fd, int irqnum, int *index_out)
267 for (irq = active_fds; irq != NULL; irq = irq->next) {
268 if ((irq->fd == fd) && (irq->irq == irqnum))
273 printk("find_irq_by_fd doesn't have descriptor %d\n", fd);
276 fdi = os_get_pollfd(i);
277 if ((fdi != -1) && (fdi != fd)) {
278 printk("find_irq_by_fd - mismatch between active_fds and "
279 "pollfds, fd %d vs %d, need %d\n", irq->fd,
289 void reactivate_fd(int fd, int irqnum)
295 spin_lock_irqsave(&irq_lock, flags);
296 irq = find_irq_by_fd(fd, irqnum, &i);
298 spin_unlock_irqrestore(&irq_lock, flags);
301 os_set_pollfd(i, irq->fd);
302 spin_unlock_irqrestore(&irq_lock, flags);
304 /* This calls activate_fd, so it has to be outside the critical
307 maybe_sigio_broken(fd, (irq->type == IRQ_READ));
310 void deactivate_fd(int fd, int irqnum)
316 spin_lock_irqsave(&irq_lock, flags);
317 irq = find_irq_by_fd(fd, irqnum, &i);
320 os_set_pollfd(i, -1);
322 spin_unlock_irqrestore(&irq_lock, flags);
325 int deactivate_all_fds(void)
330 for (irq = active_fds; irq != NULL; irq = irq->next) {
331 err = os_clear_fd_async(irq->fd);
335 /* If there is a signal already queued, after unblocking ignore it */
341 #ifdef CONFIG_MODE_TT
342 void forward_interrupts(int pid)
348 spin_lock_irqsave(&irq_lock, flags);
349 for (irq = active_fds; irq != NULL; irq = irq->next) {
350 err = os_set_owner(irq->fd, pid);
352 /* XXX Just remove the irq rather than
353 * print out an infinite stream of these
355 printk("Failed to forward %d to pid %d, err = %d\n",
361 spin_unlock_irqrestore(&irq_lock, flags);
366 * do_IRQ handles all normal device IRQ's (the special
367 * SMP cross-CPU interrupts have their own specific
370 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
373 __do_IRQ(irq, (struct pt_regs *)regs);
378 int um_request_irq(unsigned int irq, int fd, int type,
379 irqreturn_t (*handler)(int, void *, struct pt_regs *),
380 unsigned long irqflags, const char * devname,
385 err = request_irq(irq, handler, irqflags, devname, dev_id);
390 err = activate_fd(irq, fd, type, dev_id);
393 EXPORT_SYMBOL(um_request_irq);
394 EXPORT_SYMBOL(reactivate_fd);
396 /* hw_interrupt_type must define (startup || enable) &&
397 * (shutdown || disable) && end */
398 static void dummy(unsigned int irq)
402 /* This is used for everything else than the timer. */
403 static struct hw_interrupt_type normal_irq_type = {
405 .release = free_irq_by_irq_and_dev,
412 static struct hw_interrupt_type SIGVTALRM_irq_type = {
413 .typename = "SIGVTALRM",
414 .release = free_irq_by_irq_and_dev,
415 .shutdown = dummy, /* never called */
422 void __init init_IRQ(void)
426 irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
427 irq_desc[TIMER_IRQ].action = NULL;
428 irq_desc[TIMER_IRQ].depth = 1;
429 irq_desc[TIMER_IRQ].chip = &SIGVTALRM_irq_type;
430 enable_irq(TIMER_IRQ);
431 for (i = 1; i < NR_IRQS; i++) {
432 irq_desc[i].status = IRQ_DISABLED;
433 irq_desc[i].action = NULL;
434 irq_desc[i].depth = 1;
435 irq_desc[i].chip = &normal_irq_type;
440 int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
445 err = os_pipe(fds, 1, 1);
447 printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
451 err = um_request_irq(irq, fds[0], IRQ_READ, handler,
452 IRQF_DISABLED | IRQF_SAMPLE_RANDOM, name,
453 (void *) (long) fds[0]);
455 printk("init_aio_irq - : um_request_irq failed, err = %d\n",
464 os_close_file(fds[0]);
465 os_close_file(fds[1]);