1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
4 */
5
6 #include <linux/interrupt.h>
7 #include <irq_kern.h>
8 #include <os.h>
9 #include <sigio.h>
10
11 /* Protected by sigio_lock() called from write_sigio_workaround */
12 static int sigio_irq_fd = -1;
13
sigio_interrupt(int irq,void * data)14 static irqreturn_t sigio_interrupt(int irq, void *data)
15 {
16 char c;
17
18 os_read_file(sigio_irq_fd, &c, sizeof(c));
19 return IRQ_HANDLED;
20 }
21
write_sigio_irq(int fd)22 int write_sigio_irq(int fd)
23 {
24 int err;
25
26 err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
27 0, "write sigio", NULL);
28 if (err < 0) {
29 printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
30 "err = %d\n", err);
31 return -1;
32 }
33 sigio_irq_fd = fd;
34 return 0;
35 }
36
37 /* These are called from os-Linux/sigio.c to protect its pollfds arrays. */
38 static DEFINE_MUTEX(sigio_mutex);
39
sigio_lock(void)40 void sigio_lock(void)
41 {
42 mutex_lock(&sigio_mutex);
43 }
44
sigio_unlock(void)45 void sigio_unlock(void)
46 {
47 mutex_unlock(&sigio_mutex);
48 }
49