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2
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4
5
6#include <linux/slab.h>
7#include <linux/completion.h>
8#include <linux/irqreturn.h>
9#include <asm/irq.h>
10#include "irq_kern.h"
11#include "os.h"
12
13struct xterm_wait {
14 struct completion ready;
15 int fd;
16 int pid;
17 int new_fd;
18};
19
20static irqreturn_t xterm_interrupt(int irq, void *data)
21{
22 struct xterm_wait *xterm = data;
23 int fd;
24
25 fd = os_rcv_fd(xterm->fd, &xterm->pid);
26 if (fd == -EAGAIN)
27 return IRQ_NONE;
28
29 xterm->new_fd = fd;
30 complete(&xterm->ready);
31
32 return IRQ_HANDLED;
33}
34
35int xterm_fd(int socket, int *pid_out)
36{
37 struct xterm_wait *data;
38 int err, ret;
39
40 data = kmalloc(sizeof(*data), GFP_KERNEL);
41 if (data == NULL) {
42 printk(KERN_ERR "xterm_fd : failed to allocate xterm_wait\n");
43 return -ENOMEM;
44 }
45
46
47 *data = ((struct xterm_wait) { .fd = socket,
48 .pid = -1,
49 .new_fd = -1 });
50 init_completion(&data->ready);
51
52 err = um_request_irq(XTERM_IRQ, socket, IRQ_READ, xterm_interrupt,
53 IRQF_DISABLED | IRQF_SHARED | IRQF_SAMPLE_RANDOM,
54 "xterm", data);
55 if (err) {
56 printk(KERN_ERR "xterm_fd : failed to get IRQ for xterm, "
57 "err = %d\n", err);
58 ret = err;
59 goto out;
60 }
61
62
63
64
65
66 wait_for_completion(&data->ready);
67
68 free_irq(XTERM_IRQ, data);
69
70 ret = data->new_fd;
71 *pid_out = data->pid;
72 out:
73 kfree(data);
74
75 return ret;
76}
77