acrn-kernel/arch/um/kernel/sigio.c

56 lines
1.1 KiB
C

/*
* Copyright (C) 2002 - 2003 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include "linux/kernel.h"
#include "linux/list.h"
#include "linux/slab.h"
#include "linux/signal.h"
#include "linux/interrupt.h"
#include "init.h"
#include "sigio.h"
#include "irq_user.h"
#include "irq_kern.h"
#include "os.h"
/* Protected by sigio_lock() called from write_sigio_workaround */
static int sigio_irq_fd = -1;
static irqreturn_t sigio_interrupt(int irq, void *data)
{
char c;
os_read_file(sigio_irq_fd, &c, sizeof(c));
reactivate_fd(sigio_irq_fd, SIGIO_WRITE_IRQ);
return(IRQ_HANDLED);
}
int write_sigio_irq(int fd)
{
int err;
err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
IRQF_DISABLED|IRQF_SAMPLE_RANDOM, "write sigio",
NULL);
if(err){
printk("write_sigio_irq : um_request_irq failed, err = %d\n",
err);
return(-1);
}
sigio_irq_fd = fd;
return(0);
}
static DEFINE_SPINLOCK(sigio_spinlock);
void sigio_lock(void)
{
spin_lock(&sigio_spinlock);
}
void sigio_unlock(void)
{
spin_unlock(&sigio_spinlock);
}