/*
* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
* Derived (i.e. mostly copied) from arch/i386/kernel/irq.c:
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
*/
#include "linux/config.h"
#include "linux/kernel.h"
#include "linux/module.h"
#include "linux/smp.h"
#include "linux/kernel_stat.h"
#include "linux/interrupt.h"
#include "linux/random.h"
#include "linux/slab.h"
#include "linux/file.h"
#include "linux/proc_fs.h"
#include "linux/init.h"
#include "linux/seq_file.h"
#include "linux/profile.h"
#include "linux/hardirq.h"
#include "asm/irq.h"
#include "asm/hw_irq.h"
#include "asm/atomic.h"
#include "asm/signal.h"
#include "asm/system.h"
#include "asm/errno.h"
#include "asm/uaccess.h"
#include "user_util.h"
#include "kern_util.h"
#include "irq_user.h"
#include "irq_kern.h"
#include "os.h"
#include "sigio.h"
#include "misc_constants.h"
/*
* Generic, controller-independent functions:
*/
int show_interrupts(struct seq_file *p, void *v)
{
int i = *(loff_t *) v, j;
struct irqaction * action;
unsigned long flags;
if (i == 0) {
seq_printf(p, " ");
for_each_online_cpu(j)
seq_printf(p, "CPU%d ",j);
seq_putc(p, '\n');
}
if (i < NR_IRQS) {
spin_lock_irqsave(&irq_desc[i].lock, flags);
action = irq_desc[i].action;
if (!action)
goto skip;
seq_printf(p, "%3d: ",i);
#ifndef CONFIG_SMP
seq_printf(p, "%10u ", kstat_irqs(i));
#else
for_each_online_cpu(j)
seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
seq_printf(p, " %14s", irq_desc[i].handler->typename);
seq_printf(p, " %s", action->name);
for (action=action->next; action; action = action->next)
seq_printf(p, ", %s", action->name);
seq_putc(p, '\n');
skip:
spin_unlock_irqrestore(&irq_desc[i].lock, flags);
} else if (i == NR_IRQS) {
seq_putc(p, '\n');
}
return 0;
}
struct irq_fd *active_fds = NULL;
static struct irq_fd **last_irq_ptr = &active_fds;
extern void free_irqs(void);
void sigio_handler(int sig, union uml_pt_regs *regs)
{
struct irq_fd *irq_fd;
int n;
if(smp_sigio_handler()) return;
while(1){
n = os_waiting_for_events(active_fds);
if (n <= 0) {
if(n == -EINTR) continue;
else break;
}
for(irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next){
if(irq_fd->current_events != 0){
irq_fd->current_events = 0;
do_IRQ(irq_fd->irq, regs);
}
}
}
free_irqs();
}
static void maybe_sigio_broken(int fd, int type)
{
if(os_isatty(fd)){
if((type == IRQ_WRITE) && !pty_output_sigio){
write_sigio_workaround();
add_sigio_fd(fd, 0);
}
else if((type == IRQ_READ) && !pty_close_sigio){
write_sigio_workaround();
add_sigio_fd(fd, 1);
}
}
}
int activate_fd(int irq, int fd, int type, void *dev_id)
{
struct pollfd *tmp_pfd;
struct irq_fd *new_fd, *irq_fd;
unsigned long flags;
int pid, events, err, n;
pid = os_getpid();
err = os_set_fd_async(fd, pid);
if(err < 0)
goto out;
new_fd = um_kmalloc(sizeof(*new_fd));
err = -ENOMEM;
if(new_fd == NULL)
goto out;
if(type == IRQ_READ) events = UM_POLLIN | UM_POLLPRI;
else events = UM_POLLOUT;
*new_fd = ((struct irq_fd) { .next = NULL,
.id = dev_id,
.fd = fd,
.type = type,
.irq = irq,
.pid = pid,
.events = events,
.current_events = 0 } );
/* Critical section - locked by a spinlock because this stuff can
* be changed from interrupt handlers. The stuff above is done
* outside the lock because it allocates memory.
*/
/* Actually, it only looks like it can be called from interrupt
* context. The culprit is reactivate_fd, which calls
* maybe_sigio_broken, which calls write_sigio_workaround,
* which calls activate_fd. However, write_sigio_workaround should
* only be called once, at boot time. That would make it clear that
* this is called only from process context, and can be locked with
* a semaphore.
*/
flags = irq_lock();
for(irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next){
if((irq_fd->fd == fd) && (irq_fd->type == type)){
printk("Registering fd %d twice\n", fd);
printk("Irqs : %d, %d\n", irq_fd->irq, irq);
printk("Ids : 0x%p, 0x%p\n", irq_fd->id, dev_id);
goto out_unlock;
}
}
/*-------------*/
if(type == IRQ_WRITE)
fd = -1;
tmp_pfd = NULL;
n = 0;
while(1){
n = os_create_pollfd(fd, events, tmp_pfd, n);
if (n == 0)
break;
/* n > 0
* It means we couldn't put new pollfd to current pollfds
* and tmp_fds is NULL or too small for new pollfds array.
* Needed size is equal to n as minimum.
*
* Here we have to drop the lock in order to call
* kmalloc, which might sleep.
* If something else came in and changed the pollfds array
* so we will not be able to put new pollfd struct to pollfds
* then we free the buffer tmp_fds and try again.
*/
irq_unlock(flags);
if (tmp_pfd != NULL) {
kfree(tmp_pfd);
tmp_pfd = NULL;
}
tmp_pfd = um_kmalloc(n);
if (tmp_pfd == NULL)
goto out_kfree;
flags = irq_lock();
}
/*-------------*/
*last_irq_ptr = new_fd;
last_irq_ptr = &new_fd->next;
irq_unlock(flags);
/* This calls activate_fd, so it has to be outside the critical
* section.
*/
maybe_sigio_broken(fd, type);
return(0);
out_unlock:
irq_unlock(flags);
out_kfree:
kfree(new_fd);
out:
return(err);
}
static void free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg)
{
unsigned long flags;
flags = irq_lock();
os_free_irq_by_cb(test, arg, active_fds, &last_irq_ptr);
irq_unlock(flags);
}
struct irq_and_dev {
int irq;
void *dev;
};
static int same_irq_and_dev(struct irq_fd *irq, void *d)
{
struct irq_and_dev *data = d;
return((irq->irq == data->irq) && (irq->id == data->dev));
}
void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
{
struct irq_and_dev data = ((struct irq_and_dev) { .irq = irq,
.dev = dev });
free_irq_by_cb(same_irq_and_dev, &data);
}
static int same_fd(struct irq_fd *irq, void *fd)
{
return(irq->fd == *((int *) fd));
}
void free_irq_by_fd(int fd)
{
free_irq_by_cb(same_fd, &fd);
}
static struct irq_fd *find_irq_by_fd(int fd, int irqnum, int *index_out)
{
struct irq_fd *irq;
int i = 0;
int fdi;
for(irq=active_fds; irq != NULL; irq = irq->next){
if((irq->fd == fd) && (irq->irq == irqnum)) break;
i++;
}
if(irq == NULL){
printk("find_irq_by_fd doesn't have descriptor %d\n", fd);
goto out;
}
fdi = os_get_pollfd(i);
if((fdi != -1) && (fdi != fd)){
printk("find_irq_by_fd - mismatch between active_fds and "
"pollfds, fd %d vs %d, need %d\n", irq->fd,
fdi, fd);
irq = NULL;
goto out;
}
*index_out = i;
out:
return(irq);
}
void reactivate_fd(int fd, int irqnum)
{
struct irq_fd *irq;
unsigned long flags;
int i;
flags = irq_lock();
irq = find_irq_by_fd(fd, irqnum, &i);
if(irq == NULL){
irq_unlock(flags);
return;
}
os_set_pollfd(i, irq->fd);
irq_unlock(flags);
/* This calls activate_fd, so it has to be outside the critical
* section.
*/
maybe_sigio_broken(fd, irq->type);
}
void deactivate_fd(int fd, int irqnum)
{
struct irq_fd *irq;
unsigned long flags;
int i;
flags = irq_lock();
irq = find_irq_by_fd(fd, irqnum, &i);
if(irq == NULL)
goto out;
os_set_pollfd(i, -1);
out:
irq_unlock(flags);
}
int deactivate_all_fds(void)
{
struct irq_fd *irq;
int err;
for(irq=active_fds;irq != NULL;irq = irq->next){
err = os_clear_fd_async(irq->fd);
if(err)
return(err);
}
/* If there is a signal already queued, after unblocking ignore it */
os_set_ioignore();
return(0);
}
void forward_interrupts(int pid)
{
struct irq_fd *irq;
unsigned long flags;
int err;
flags = irq_lock();
for(irq=active_fds;irq != NULL;irq = irq->next){
err = os_set_owner(irq->fd, pid);
if(err < 0){
/* XXX Just remove the irq rather than
* print out an infinite stream of these
*/
printk("Failed to forward %d to pid %d, err = %d\n",
irq->fd, pid, -err);
}
irq->pid = pid;
}
irq_unlock(flags);
}
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*/
unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
{
irq_enter();
__do_IRQ(irq, (struct pt_regs *) regs);
irq_exit();
return 1;
}
int um_request_irq(unsigned int irq, int fd, int type,
irqreturn_t (*handler)(int, void *, struct pt_regs *),
unsigned long irqflags, const char * devname,
void *dev_id)
{
int err;
err = request_irq(irq, handler, irqflags, devname, dev_id);
if(err)
return(err);
if(fd != -1)
err = activate_fd(irq, fd, type, dev_id);
return(err);
}
EXPORT_SYMBOL(um_request_irq);
EXPORT_SYMBOL(reactivate_fd);
static DEFINE_SPINLOCK(irq_spinlock);
unsigned long irq_lock(void)
{
unsigned long flags;
spin_lock_irqsave(&irq_spinlock, flags);
return(flags);
}
void irq_unlock(unsigned long flags)
{
spin_unlock_irqrestore(&irq_spinlock, flags);
}
/* hw_interrupt_type must define (startup || enable) &&
* (shutdown || disable) && end */
static void dummy(unsigned int irq)
{
}
/* This is used for everything else than the timer. */
static struct hw_interrupt_type normal_irq_type = {
.typename = "SIGIO",
.release = free_irq_by_irq_and_dev,
.disable = dummy,
.enable = dummy,
.ack = dummy,
.end = dummy
};
static struct hw_interrupt_type SIGVTALRM_irq_type = {
.typename = "SIGVTALRM",
.release = free_irq_by_irq_and_dev,
.shutdown = dummy, /* never called */
.disable = dummy,
.enable = dummy,
.ack = dummy,
.end = dummy
};
void __init init_IRQ(void)
{
int i;
irq_desc[TIMER_IRQ].status = IRQ_DISABLED;
irq_desc[TIMER_IRQ].action = NULL;
irq_desc[TIMER_IRQ].depth = 1;
irq_desc[TIMER_IRQ].handler = &SIGVTALRM_irq_type;
enable_irq(TIMER_IRQ);
for(i=1;i<NR_IRQS;i++){
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = NULL;
irq_desc[i].depth = 1;
irq_desc[i].handler = &normal_irq_type;
enable_irq(i);
}
}
int init_aio_irq(int irq, char *name, irqreturn_t (*handler)(int, void *,
struct pt_regs *))
{
int fds[2], err;
err = os_pipe(fds, 1, 1);
if(err){
printk("init_aio_irq - os_pipe failed, err = %d\n", -err);
goto out;
}
err = um_request_irq(irq, fds[0], IRQ_READ, handler,
SA_INTERRUPT | SA_SAMPLE_RANDOM, name,
(void *) (long) fds[0]);
if(err){
printk("init_aio_irq - : um_request_irq failed, err = %d\n",
err);
goto out_close;
}
err = fds[1];
goto out;
out_close:
os_close_file(fds[0]);
os_close_file(fds[1]);
out:
return(err);
}
