1 | /* |
---|
2 | * This program is free software; you can redistribute it and/or |
---|
3 | * modify it under the terms of the GNU General Public License version 2 |
---|
4 | * as published by the Free Software Foundation; or, when distributed |
---|
5 | * separately from the Linux kernel or incorporated into other |
---|
6 | * software packages, subject to the following license: |
---|
7 | * |
---|
8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
---|
9 | * of this source file (the "Software"), to deal in the Software without |
---|
10 | * restriction, including without limitation the rights to use, copy, modify, |
---|
11 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
---|
12 | * and to permit persons to whom the Software is furnished to do so, subject to |
---|
13 | * the following conditions: |
---|
14 | * |
---|
15 | * The above copyright notice and this permission notice shall be included in |
---|
16 | * all copies or substantial portions of the Software. |
---|
17 | * |
---|
18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
---|
19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
---|
20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
---|
21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
---|
22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
---|
23 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
---|
24 | * IN THE SOFTWARE. |
---|
25 | */ |
---|
26 | |
---|
27 | #include <linux/version.h> |
---|
28 | #include <linux/module.h> |
---|
29 | #include <linux/errno.h> |
---|
30 | #include <linux/signal.h> |
---|
31 | #include <linux/sched.h> |
---|
32 | #include <linux/interrupt.h> |
---|
33 | #include <linux/tty.h> |
---|
34 | #include <linux/tty_flip.h> |
---|
35 | #include <linux/serial.h> |
---|
36 | #include <linux/major.h> |
---|
37 | #include <linux/ptrace.h> |
---|
38 | #include <linux/ioport.h> |
---|
39 | #include <linux/mm.h> |
---|
40 | #include <linux/slab.h> |
---|
41 | |
---|
42 | #include <asm/hypervisor.h> |
---|
43 | #include <xen/evtchn.h> |
---|
44 | #include <xen/xencons.h> |
---|
45 | #include <linux/wait.h> |
---|
46 | #include <linux/interrupt.h> |
---|
47 | #include <linux/sched.h> |
---|
48 | #include <linux/err.h> |
---|
49 | #include <xen/interface/io/console.h> |
---|
50 | |
---|
51 | static int xencons_irq; |
---|
52 | |
---|
53 | static inline struct xencons_interface *xencons_interface(void) |
---|
54 | { |
---|
55 | return mfn_to_virt(xen_start_info->console.domU.mfn); |
---|
56 | } |
---|
57 | |
---|
58 | static inline void notify_daemon(void) |
---|
59 | { |
---|
60 | /* Use evtchn: this is called early, before irq is set up. */ |
---|
61 | notify_remote_via_evtchn(xen_start_info->console.domU.evtchn); |
---|
62 | } |
---|
63 | |
---|
64 | int xencons_ring_send(const char *data, unsigned len) |
---|
65 | { |
---|
66 | int sent = 0; |
---|
67 | struct xencons_interface *intf = xencons_interface(); |
---|
68 | XENCONS_RING_IDX cons, prod; |
---|
69 | |
---|
70 | cons = intf->out_cons; |
---|
71 | prod = intf->out_prod; |
---|
72 | mb(); |
---|
73 | BUG_ON((prod - cons) > sizeof(intf->out)); |
---|
74 | |
---|
75 | while ((sent < len) && ((prod - cons) < sizeof(intf->out))) |
---|
76 | intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++]; |
---|
77 | |
---|
78 | wmb(); |
---|
79 | intf->out_prod = prod; |
---|
80 | |
---|
81 | notify_daemon(); |
---|
82 | |
---|
83 | return sent; |
---|
84 | } |
---|
85 | |
---|
86 | static irqreturn_t handle_input(int irq, void *unused, struct pt_regs *regs) |
---|
87 | { |
---|
88 | struct xencons_interface *intf = xencons_interface(); |
---|
89 | XENCONS_RING_IDX cons, prod; |
---|
90 | |
---|
91 | cons = intf->in_cons; |
---|
92 | prod = intf->in_prod; |
---|
93 | mb(); |
---|
94 | BUG_ON((prod - cons) > sizeof(intf->in)); |
---|
95 | |
---|
96 | while (cons != prod) { |
---|
97 | xencons_rx(intf->in+MASK_XENCONS_IDX(cons,intf->in), 1, regs); |
---|
98 | cons++; |
---|
99 | } |
---|
100 | |
---|
101 | mb(); |
---|
102 | intf->in_cons = cons; |
---|
103 | |
---|
104 | notify_daemon(); |
---|
105 | |
---|
106 | xencons_tx(); |
---|
107 | |
---|
108 | return IRQ_HANDLED; |
---|
109 | } |
---|
110 | |
---|
111 | int xencons_ring_init(void) |
---|
112 | { |
---|
113 | int irq; |
---|
114 | |
---|
115 | if (xencons_irq) |
---|
116 | unbind_from_irqhandler(xencons_irq, NULL); |
---|
117 | xencons_irq = 0; |
---|
118 | |
---|
119 | if (!is_running_on_xen() || |
---|
120 | is_initial_xendomain() || |
---|
121 | !xen_start_info->console.domU.evtchn) |
---|
122 | return -ENODEV; |
---|
123 | |
---|
124 | irq = bind_caller_port_to_irqhandler( |
---|
125 | xen_start_info->console.domU.evtchn, |
---|
126 | handle_input, 0, "xencons", NULL); |
---|
127 | if (irq < 0) { |
---|
128 | printk(KERN_ERR "XEN console request irq failed %i\n", irq); |
---|
129 | return irq; |
---|
130 | } |
---|
131 | |
---|
132 | xencons_irq = irq; |
---|
133 | |
---|
134 | /* In case we have in-flight data after save/restore... */ |
---|
135 | notify_daemon(); |
---|
136 | |
---|
137 | return 0; |
---|
138 | } |
---|
139 | |
---|
140 | void xencons_resume(void) |
---|
141 | { |
---|
142 | (void)xencons_ring_init(); |
---|
143 | } |
---|