1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
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 | #include "xterm.h" |
13 | |
14 | struct xterm_wait { |
15 | struct completion ready; |
16 | int fd; |
17 | int pid; |
18 | int new_fd; |
19 | }; |
20 | |
21 | static irqreturn_t xterm_interrupt(int irq, void *data) |
22 | { |
23 | struct xterm_wait *xterm = data; |
24 | int fd; |
25 | |
26 | fd = os_rcv_fd(xterm->fd, &xterm->pid); |
27 | if (fd == -EAGAIN) |
28 | return IRQ_NONE; |
29 | |
30 | xterm->new_fd = fd; |
31 | complete(&xterm->ready); |
32 | |
33 | return IRQ_HANDLED; |
34 | } |
35 | |
36 | int xterm_fd(int socket, int *pid_out) |
37 | { |
38 | struct xterm_wait *data; |
39 | int err, ret; |
40 | |
41 | data = kmalloc(size: sizeof(*data), GFP_KERNEL); |
42 | if (data == NULL) { |
43 | printk(KERN_ERR "xterm_fd : failed to allocate xterm_wait\n" ); |
44 | return -ENOMEM; |
45 | } |
46 | |
47 | /* This is a locked semaphore... */ |
48 | *data = ((struct xterm_wait) { .fd = socket, |
49 | .pid = -1, |
50 | .new_fd = -1 }); |
51 | init_completion(x: &data->ready); |
52 | |
53 | err = um_request_irq(XTERM_IRQ, socket, IRQ_READ, xterm_interrupt, |
54 | IRQF_SHARED, "xterm" , data); |
55 | if (err < 0) { |
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 | /* ... so here we wait for an xterm interrupt. |
63 | * |
64 | * XXX Note, if the xterm doesn't work for some reason (eg. DISPLAY |
65 | * isn't set) this will hang... */ |
66 | wait_for_completion(&data->ready); |
67 | |
68 | um_free_irq(XTERM_IRQ, data); |
69 | |
70 | ret = data->new_fd; |
71 | *pid_out = data->pid; |
72 | out: |
73 | kfree(objp: data); |
74 | |
75 | return ret; |
76 | } |
77 | |