]>
Commit | Line | Data |
---|---|---|
3e2b8fbe JF |
1 | /* |
2 | * Handle extern requests for shutdown, reboot and sysrq | |
3 | */ | |
4 | #include <linux/kernel.h> | |
5 | #include <linux/err.h> | |
5a0e3ad6 | 6 | #include <linux/slab.h> |
3e2b8fbe JF |
7 | #include <linux/reboot.h> |
8 | #include <linux/sysrq.h> | |
0e91398f JF |
9 | #include <linux/stop_machine.h> |
10 | #include <linux/freezer.h> | |
3e2b8fbe | 11 | |
016b6f5f | 12 | #include <xen/xen.h> |
3e2b8fbe | 13 | #include <xen/xenbus.h> |
0e91398f JF |
14 | #include <xen/grant_table.h> |
15 | #include <xen/events.h> | |
16 | #include <xen/hvc-console.h> | |
17 | #include <xen/xen-ops.h> | |
3e2b8fbe | 18 | |
0e91398f JF |
19 | #include <asm/xen/hypercall.h> |
20 | #include <asm/xen/page.h> | |
016b6f5f | 21 | #include <asm/xen/hypervisor.h> |
0e91398f JF |
22 | |
23 | enum shutdown_state { | |
24 | SHUTDOWN_INVALID = -1, | |
25 | SHUTDOWN_POWEROFF = 0, | |
26 | SHUTDOWN_SUSPEND = 2, | |
27 | /* Code 3 is SHUTDOWN_CRASH, which we don't use because the domain can only | |
28 | report a crash, not be instructed to crash! | |
29 | HALT is the same as POWEROFF, as far as we're concerned. The tools use | |
30 | the distinction when we return the reason code to them. */ | |
31 | SHUTDOWN_HALT = 4, | |
32 | }; | |
3e2b8fbe JF |
33 | |
34 | /* Ignore multiple shutdown requests. */ | |
0e91398f JF |
35 | static enum shutdown_state shutting_down = SHUTDOWN_INVALID; |
36 | ||
c7827728 | 37 | #ifdef CONFIG_PM_SLEEP |
016b6f5f | 38 | static int xen_hvm_suspend(void *data) |
0e91398f | 39 | { |
016b6f5f | 40 | struct sched_shutdown r = { .reason = SHUTDOWN_suspend }; |
0e91398f | 41 | int *cancelled = data; |
016b6f5f SS |
42 | |
43 | BUG_ON(!irqs_disabled()); | |
44 | ||
45 | *cancelled = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r); | |
46 | ||
47 | xen_hvm_post_suspend(*cancelled); | |
48 | gnttab_resume(); | |
49 | ||
50 | if (!*cancelled) { | |
51 | xen_irq_resume(); | |
6411fe69 | 52 | xen_console_resume(); |
016b6f5f SS |
53 | xen_timer_resume(); |
54 | } | |
55 | ||
56 | return 0; | |
57 | } | |
58 | ||
59 | static int xen_suspend(void *data) | |
60 | { | |
359cdd3f | 61 | int err; |
016b6f5f | 62 | int *cancelled = data; |
0e91398f JF |
63 | |
64 | BUG_ON(!irqs_disabled()); | |
65 | ||
770824bd RW |
66 | err = sysdev_suspend(PMSG_SUSPEND); |
67 | if (err) { | |
68 | printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n", | |
69 | err); | |
770824bd RW |
70 | return err; |
71 | } | |
359cdd3f | 72 | |
0e91398f JF |
73 | xen_mm_pin_all(); |
74 | gnttab_suspend(); | |
0e91398f JF |
75 | xen_pre_suspend(); |
76 | ||
77 | /* | |
78 | * This hypercall returns 1 if suspend was cancelled | |
79 | * or the domain was merely checkpointed, and 0 if it | |
80 | * is resuming in a new domain. | |
81 | */ | |
82 | *cancelled = HYPERVISOR_suspend(virt_to_mfn(xen_start_info)); | |
83 | ||
84 | xen_post_suspend(*cancelled); | |
0e91398f JF |
85 | gnttab_resume(); |
86 | xen_mm_unpin_all(); | |
87 | ||
88 | if (!*cancelled) { | |
89 | xen_irq_resume(); | |
90 | xen_console_resume(); | |
ad55db9f | 91 | xen_timer_resume(); |
0e91398f JF |
92 | } |
93 | ||
1e6fcf84 | 94 | sysdev_resume(); |
1e6fcf84 | 95 | |
0e91398f JF |
96 | return 0; |
97 | } | |
98 | ||
99 | static void do_suspend(void) | |
100 | { | |
101 | int err; | |
102 | int cancelled = 1; | |
103 | ||
104 | shutting_down = SHUTDOWN_SUSPEND; | |
105 | ||
106 | #ifdef CONFIG_PREEMPT | |
107 | /* If the kernel is preemptible, we need to freeze all the processes | |
108 | to prevent them from being in the middle of a pagetable update | |
109 | during suspend. */ | |
110 | err = freeze_processes(); | |
111 | if (err) { | |
112 | printk(KERN_ERR "xen suspend: freeze failed %d\n", err); | |
3fc1f1e2 | 113 | goto out; |
0e91398f JF |
114 | } |
115 | #endif | |
116 | ||
d1616302 | 117 | err = dpm_suspend_start(PMSG_SUSPEND); |
0e91398f | 118 | if (err) { |
d1616302 | 119 | printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err); |
65f63384 | 120 | goto out_thaw; |
0e91398f JF |
121 | } |
122 | ||
c5cae661 IC |
123 | printk(KERN_DEBUG "suspending xenstore...\n"); |
124 | xs_suspend(); | |
125 | ||
d1616302 | 126 | err = dpm_suspend_noirq(PMSG_SUSPEND); |
2ed8d2b3 | 127 | if (err) { |
d1616302 | 128 | printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err); |
65f63384 | 129 | goto out_resume; |
2ed8d2b3 RW |
130 | } |
131 | ||
016b6f5f SS |
132 | if (xen_hvm_domain()) |
133 | err = stop_machine(xen_hvm_suspend, &cancelled, cpumask_of(0)); | |
134 | else | |
135 | err = stop_machine(xen_suspend, &cancelled, cpumask_of(0)); | |
922cc38a JF |
136 | |
137 | dpm_resume_noirq(PMSG_RESUME); | |
138 | ||
0e91398f JF |
139 | if (err) { |
140 | printk(KERN_ERR "failed to start xen_suspend: %d\n", err); | |
65f63384 | 141 | cancelled = 1; |
0e91398f JF |
142 | } |
143 | ||
c5cae661 | 144 | out_resume: |
ad55db9f IY |
145 | if (!cancelled) { |
146 | xen_arch_resume(); | |
de5b31bd | 147 | xs_resume(); |
ad55db9f | 148 | } else |
de5b31bd | 149 | xs_suspend_cancel(); |
0e91398f | 150 | |
d1616302 | 151 | dpm_resume_end(PMSG_RESUME); |
0e91398f | 152 | |
359cdd3f JF |
153 | /* Make sure timer events get retriggered on all CPUs */ |
154 | clock_was_set(); | |
65f63384 IC |
155 | |
156 | out_thaw: | |
0e91398f JF |
157 | #ifdef CONFIG_PREEMPT |
158 | thaw_processes(); | |
65f63384 | 159 | out: |
3fc1f1e2 | 160 | #endif |
0e91398f JF |
161 | shutting_down = SHUTDOWN_INVALID; |
162 | } | |
c7827728 | 163 | #endif /* CONFIG_PM_SLEEP */ |
3e2b8fbe JF |
164 | |
165 | static void shutdown_handler(struct xenbus_watch *watch, | |
166 | const char **vec, unsigned int len) | |
167 | { | |
168 | char *str; | |
169 | struct xenbus_transaction xbt; | |
170 | int err; | |
171 | ||
172 | if (shutting_down != SHUTDOWN_INVALID) | |
173 | return; | |
174 | ||
175 | again: | |
176 | err = xenbus_transaction_start(&xbt); | |
177 | if (err) | |
178 | return; | |
179 | ||
180 | str = (char *)xenbus_read(xbt, "control", "shutdown", NULL); | |
181 | /* Ignore read errors and empty reads. */ | |
182 | if (XENBUS_IS_ERR_READ(str)) { | |
183 | xenbus_transaction_end(xbt, 1); | |
184 | return; | |
185 | } | |
186 | ||
187 | xenbus_write(xbt, "control", "shutdown", ""); | |
188 | ||
189 | err = xenbus_transaction_end(xbt, 0); | |
190 | if (err == -EAGAIN) { | |
191 | kfree(str); | |
192 | goto again; | |
193 | } | |
194 | ||
195 | if (strcmp(str, "poweroff") == 0 || | |
0e91398f JF |
196 | strcmp(str, "halt") == 0) { |
197 | shutting_down = SHUTDOWN_POWEROFF; | |
3e2b8fbe | 198 | orderly_poweroff(false); |
0e91398f JF |
199 | } else if (strcmp(str, "reboot") == 0) { |
200 | shutting_down = SHUTDOWN_POWEROFF; /* ? */ | |
3e2b8fbe | 201 | ctrl_alt_del(); |
0e91398f JF |
202 | #ifdef CONFIG_PM_SLEEP |
203 | } else if (strcmp(str, "suspend") == 0) { | |
204 | do_suspend(); | |
205 | #endif | |
206 | } else { | |
3e2b8fbe JF |
207 | printk(KERN_INFO "Ignoring shutdown request: %s\n", str); |
208 | shutting_down = SHUTDOWN_INVALID; | |
209 | } | |
210 | ||
211 | kfree(str); | |
212 | } | |
213 | ||
f3bc3189 | 214 | #ifdef CONFIG_MAGIC_SYSRQ |
3e2b8fbe JF |
215 | static void sysrq_handler(struct xenbus_watch *watch, const char **vec, |
216 | unsigned int len) | |
217 | { | |
218 | char sysrq_key = '\0'; | |
219 | struct xenbus_transaction xbt; | |
220 | int err; | |
221 | ||
222 | again: | |
223 | err = xenbus_transaction_start(&xbt); | |
224 | if (err) | |
225 | return; | |
226 | if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) { | |
227 | printk(KERN_ERR "Unable to read sysrq code in " | |
228 | "control/sysrq\n"); | |
229 | xenbus_transaction_end(xbt, 1); | |
230 | return; | |
231 | } | |
232 | ||
233 | if (sysrq_key != '\0') | |
234 | xenbus_printf(xbt, "control", "sysrq", "%c", '\0'); | |
235 | ||
236 | err = xenbus_transaction_end(xbt, 0); | |
237 | if (err == -EAGAIN) | |
238 | goto again; | |
239 | ||
240 | if (sysrq_key != '\0') | |
f335397d | 241 | handle_sysrq(sysrq_key); |
3e2b8fbe JF |
242 | } |
243 | ||
3e2b8fbe JF |
244 | static struct xenbus_watch sysrq_watch = { |
245 | .node = "control/sysrq", | |
246 | .callback = sysrq_handler | |
247 | }; | |
f3bc3189 RD |
248 | #endif |
249 | ||
250 | static struct xenbus_watch shutdown_watch = { | |
251 | .node = "control/shutdown", | |
252 | .callback = shutdown_handler | |
253 | }; | |
3e2b8fbe JF |
254 | |
255 | static int setup_shutdown_watcher(void) | |
256 | { | |
257 | int err; | |
258 | ||
259 | err = register_xenbus_watch(&shutdown_watch); | |
260 | if (err) { | |
261 | printk(KERN_ERR "Failed to set shutdown watcher\n"); | |
262 | return err; | |
263 | } | |
264 | ||
f3bc3189 | 265 | #ifdef CONFIG_MAGIC_SYSRQ |
3e2b8fbe JF |
266 | err = register_xenbus_watch(&sysrq_watch); |
267 | if (err) { | |
268 | printk(KERN_ERR "Failed to set sysrq watcher\n"); | |
269 | return err; | |
270 | } | |
f3bc3189 | 271 | #endif |
3e2b8fbe JF |
272 | |
273 | return 0; | |
274 | } | |
275 | ||
276 | static int shutdown_event(struct notifier_block *notifier, | |
277 | unsigned long event, | |
278 | void *data) | |
279 | { | |
280 | setup_shutdown_watcher(); | |
281 | return NOTIFY_DONE; | |
282 | } | |
283 | ||
016b6f5f SS |
284 | static int __init __setup_shutdown_event(void) |
285 | { | |
286 | /* Delay initialization in the PV on HVM case */ | |
287 | if (xen_hvm_domain()) | |
288 | return 0; | |
289 | ||
290 | if (!xen_pv_domain()) | |
291 | return -ENODEV; | |
292 | ||
293 | return xen_setup_shutdown_event(); | |
294 | } | |
295 | ||
296 | int xen_setup_shutdown_event(void) | |
3e2b8fbe JF |
297 | { |
298 | static struct notifier_block xenstore_notifier = { | |
299 | .notifier_call = shutdown_event | |
300 | }; | |
301 | register_xenstore_notifier(&xenstore_notifier); | |
302 | ||
303 | return 0; | |
304 | } | |
183d03cc | 305 | EXPORT_SYMBOL_GPL(xen_setup_shutdown_event); |
3e2b8fbe | 306 | |
016b6f5f | 307 | subsys_initcall(__setup_shutdown_event); |