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 | ||
ceb18029 IC |
37 | struct suspend_info { |
38 | int cancelled; | |
39 | }; | |
40 | ||
c7827728 | 41 | #ifdef CONFIG_PM_SLEEP |
016b6f5f | 42 | static int xen_hvm_suspend(void *data) |
0e91398f | 43 | { |
ceb18029 | 44 | struct suspend_info *si = data; |
8dd38383 | 45 | int err; |
016b6f5f SS |
46 | |
47 | BUG_ON(!irqs_disabled()); | |
48 | ||
8dd38383 IC |
49 | err = sysdev_suspend(PMSG_SUSPEND); |
50 | if (err) { | |
51 | printk(KERN_ERR "xen_hvm_suspend: sysdev_suspend failed: %d\n", | |
52 | err); | |
53 | return err; | |
54 | } | |
55 | ||
bd1c0ad2 IC |
56 | /* |
57 | * This hypercall returns 1 if suspend was cancelled | |
58 | * or the domain was merely checkpointed, and 0 if it | |
59 | * is resuming in a new domain. | |
60 | */ | |
ceb18029 | 61 | si->cancelled = HYPERVISOR_suspend(0UL); |
016b6f5f | 62 | |
ceb18029 | 63 | xen_hvm_post_suspend(si->cancelled); |
016b6f5f SS |
64 | gnttab_resume(); |
65 | ||
ceb18029 | 66 | if (!si->cancelled) { |
016b6f5f | 67 | xen_irq_resume(); |
6411fe69 | 68 | xen_console_resume(); |
016b6f5f SS |
69 | xen_timer_resume(); |
70 | } | |
71 | ||
8dd38383 IC |
72 | sysdev_resume(); |
73 | ||
016b6f5f SS |
74 | return 0; |
75 | } | |
76 | ||
77 | static int xen_suspend(void *data) | |
78 | { | |
ceb18029 | 79 | struct suspend_info *si = data; |
359cdd3f | 80 | int err; |
0e91398f JF |
81 | |
82 | BUG_ON(!irqs_disabled()); | |
83 | ||
770824bd RW |
84 | err = sysdev_suspend(PMSG_SUSPEND); |
85 | if (err) { | |
86 | printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n", | |
87 | err); | |
770824bd RW |
88 | return err; |
89 | } | |
359cdd3f | 90 | |
0e91398f JF |
91 | xen_mm_pin_all(); |
92 | gnttab_suspend(); | |
0e91398f JF |
93 | xen_pre_suspend(); |
94 | ||
95 | /* | |
96 | * This hypercall returns 1 if suspend was cancelled | |
97 | * or the domain was merely checkpointed, and 0 if it | |
98 | * is resuming in a new domain. | |
99 | */ | |
ceb18029 | 100 | si->cancelled = HYPERVISOR_suspend(virt_to_mfn(xen_start_info)); |
0e91398f | 101 | |
ceb18029 | 102 | xen_post_suspend(si->cancelled); |
0e91398f JF |
103 | gnttab_resume(); |
104 | xen_mm_unpin_all(); | |
105 | ||
ceb18029 | 106 | if (!si->cancelled) { |
0e91398f JF |
107 | xen_irq_resume(); |
108 | xen_console_resume(); | |
ad55db9f | 109 | xen_timer_resume(); |
0e91398f JF |
110 | } |
111 | ||
1e6fcf84 | 112 | sysdev_resume(); |
1e6fcf84 | 113 | |
0e91398f JF |
114 | return 0; |
115 | } | |
116 | ||
117 | static void do_suspend(void) | |
118 | { | |
119 | int err; | |
ceb18029 | 120 | struct suspend_info si; |
0e91398f JF |
121 | |
122 | shutting_down = SHUTDOWN_SUSPEND; | |
123 | ||
124 | #ifdef CONFIG_PREEMPT | |
125 | /* If the kernel is preemptible, we need to freeze all the processes | |
126 | to prevent them from being in the middle of a pagetable update | |
127 | during suspend. */ | |
128 | err = freeze_processes(); | |
129 | if (err) { | |
130 | printk(KERN_ERR "xen suspend: freeze failed %d\n", err); | |
3fc1f1e2 | 131 | goto out; |
0e91398f JF |
132 | } |
133 | #endif | |
134 | ||
d1616302 | 135 | err = dpm_suspend_start(PMSG_SUSPEND); |
0e91398f | 136 | if (err) { |
d1616302 | 137 | printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err); |
65f63384 | 138 | goto out_thaw; |
0e91398f JF |
139 | } |
140 | ||
c5cae661 IC |
141 | printk(KERN_DEBUG "suspending xenstore...\n"); |
142 | xs_suspend(); | |
143 | ||
d1616302 | 144 | err = dpm_suspend_noirq(PMSG_SUSPEND); |
2ed8d2b3 | 145 | if (err) { |
d1616302 | 146 | printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err); |
65f63384 | 147 | goto out_resume; |
2ed8d2b3 RW |
148 | } |
149 | ||
ceb18029 IC |
150 | si.cancelled = 1; |
151 | ||
016b6f5f | 152 | if (xen_hvm_domain()) |
ceb18029 | 153 | err = stop_machine(xen_hvm_suspend, &si, cpumask_of(0)); |
016b6f5f | 154 | else |
ceb18029 | 155 | err = stop_machine(xen_suspend, &si, cpumask_of(0)); |
922cc38a JF |
156 | |
157 | dpm_resume_noirq(PMSG_RESUME); | |
158 | ||
0e91398f JF |
159 | if (err) { |
160 | printk(KERN_ERR "failed to start xen_suspend: %d\n", err); | |
ceb18029 | 161 | si.cancelled = 1; |
0e91398f JF |
162 | } |
163 | ||
c5cae661 | 164 | out_resume: |
ceb18029 | 165 | if (!si.cancelled) { |
ad55db9f | 166 | xen_arch_resume(); |
de5b31bd | 167 | xs_resume(); |
ad55db9f | 168 | } else |
de5b31bd | 169 | xs_suspend_cancel(); |
0e91398f | 170 | |
d1616302 | 171 | dpm_resume_end(PMSG_RESUME); |
0e91398f | 172 | |
359cdd3f JF |
173 | /* Make sure timer events get retriggered on all CPUs */ |
174 | clock_was_set(); | |
65f63384 IC |
175 | |
176 | out_thaw: | |
0e91398f JF |
177 | #ifdef CONFIG_PREEMPT |
178 | thaw_processes(); | |
65f63384 | 179 | out: |
3fc1f1e2 | 180 | #endif |
0e91398f JF |
181 | shutting_down = SHUTDOWN_INVALID; |
182 | } | |
c7827728 | 183 | #endif /* CONFIG_PM_SLEEP */ |
3e2b8fbe | 184 | |
55271723 IC |
185 | struct shutdown_handler { |
186 | const char *command; | |
187 | void (*cb)(void); | |
188 | }; | |
189 | ||
190 | static void do_poweroff(void) | |
191 | { | |
192 | shutting_down = SHUTDOWN_POWEROFF; | |
193 | orderly_poweroff(false); | |
194 | } | |
195 | ||
196 | static void do_reboot(void) | |
197 | { | |
198 | shutting_down = SHUTDOWN_POWEROFF; /* ? */ | |
199 | ctrl_alt_del(); | |
200 | } | |
201 | ||
3e2b8fbe JF |
202 | static void shutdown_handler(struct xenbus_watch *watch, |
203 | const char **vec, unsigned int len) | |
204 | { | |
205 | char *str; | |
206 | struct xenbus_transaction xbt; | |
207 | int err; | |
55271723 IC |
208 | static struct shutdown_handler handlers[] = { |
209 | { "poweroff", do_poweroff }, | |
210 | { "halt", do_poweroff }, | |
211 | { "reboot", do_reboot }, | |
212 | #ifdef CONFIG_PM_SLEEP | |
213 | { "suspend", do_suspend }, | |
214 | #endif | |
215 | {NULL, NULL}, | |
216 | }; | |
217 | static struct shutdown_handler *handler; | |
3e2b8fbe JF |
218 | |
219 | if (shutting_down != SHUTDOWN_INVALID) | |
220 | return; | |
221 | ||
222 | again: | |
223 | err = xenbus_transaction_start(&xbt); | |
224 | if (err) | |
225 | return; | |
226 | ||
227 | str = (char *)xenbus_read(xbt, "control", "shutdown", NULL); | |
228 | /* Ignore read errors and empty reads. */ | |
229 | if (XENBUS_IS_ERR_READ(str)) { | |
230 | xenbus_transaction_end(xbt, 1); | |
231 | return; | |
232 | } | |
233 | ||
55271723 IC |
234 | for (handler = &handlers[0]; handler->command; handler++) { |
235 | if (strcmp(str, handler->command) == 0) | |
236 | break; | |
237 | } | |
238 | ||
239 | /* Only acknowledge commands which we are prepared to handle. */ | |
240 | if (handler->cb) | |
241 | xenbus_write(xbt, "control", "shutdown", ""); | |
3e2b8fbe JF |
242 | |
243 | err = xenbus_transaction_end(xbt, 0); | |
244 | if (err == -EAGAIN) { | |
245 | kfree(str); | |
246 | goto again; | |
247 | } | |
248 | ||
55271723 IC |
249 | if (handler->cb) { |
250 | handler->cb(); | |
0e91398f | 251 | } else { |
3e2b8fbe JF |
252 | printk(KERN_INFO "Ignoring shutdown request: %s\n", str); |
253 | shutting_down = SHUTDOWN_INVALID; | |
254 | } | |
255 | ||
256 | kfree(str); | |
257 | } | |
258 | ||
f3bc3189 | 259 | #ifdef CONFIG_MAGIC_SYSRQ |
3e2b8fbe JF |
260 | static void sysrq_handler(struct xenbus_watch *watch, const char **vec, |
261 | unsigned int len) | |
262 | { | |
263 | char sysrq_key = '\0'; | |
264 | struct xenbus_transaction xbt; | |
265 | int err; | |
266 | ||
267 | again: | |
268 | err = xenbus_transaction_start(&xbt); | |
269 | if (err) | |
270 | return; | |
271 | if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) { | |
272 | printk(KERN_ERR "Unable to read sysrq code in " | |
273 | "control/sysrq\n"); | |
274 | xenbus_transaction_end(xbt, 1); | |
275 | return; | |
276 | } | |
277 | ||
278 | if (sysrq_key != '\0') | |
279 | xenbus_printf(xbt, "control", "sysrq", "%c", '\0'); | |
280 | ||
281 | err = xenbus_transaction_end(xbt, 0); | |
282 | if (err == -EAGAIN) | |
283 | goto again; | |
284 | ||
285 | if (sysrq_key != '\0') | |
f335397d | 286 | handle_sysrq(sysrq_key); |
3e2b8fbe JF |
287 | } |
288 | ||
3e2b8fbe JF |
289 | static struct xenbus_watch sysrq_watch = { |
290 | .node = "control/sysrq", | |
291 | .callback = sysrq_handler | |
292 | }; | |
f3bc3189 RD |
293 | #endif |
294 | ||
295 | static struct xenbus_watch shutdown_watch = { | |
296 | .node = "control/shutdown", | |
297 | .callback = shutdown_handler | |
298 | }; | |
3e2b8fbe JF |
299 | |
300 | static int setup_shutdown_watcher(void) | |
301 | { | |
302 | int err; | |
303 | ||
304 | err = register_xenbus_watch(&shutdown_watch); | |
305 | if (err) { | |
306 | printk(KERN_ERR "Failed to set shutdown watcher\n"); | |
307 | return err; | |
308 | } | |
309 | ||
f3bc3189 | 310 | #ifdef CONFIG_MAGIC_SYSRQ |
3e2b8fbe JF |
311 | err = register_xenbus_watch(&sysrq_watch); |
312 | if (err) { | |
313 | printk(KERN_ERR "Failed to set sysrq watcher\n"); | |
314 | return err; | |
315 | } | |
f3bc3189 | 316 | #endif |
3e2b8fbe JF |
317 | |
318 | return 0; | |
319 | } | |
320 | ||
321 | static int shutdown_event(struct notifier_block *notifier, | |
322 | unsigned long event, | |
323 | void *data) | |
324 | { | |
325 | setup_shutdown_watcher(); | |
326 | return NOTIFY_DONE; | |
327 | } | |
328 | ||
016b6f5f | 329 | int xen_setup_shutdown_event(void) |
3e2b8fbe JF |
330 | { |
331 | static struct notifier_block xenstore_notifier = { | |
332 | .notifier_call = shutdown_event | |
333 | }; | |
702d4eb9 SS |
334 | |
335 | if (!xen_domain()) | |
336 | return -ENODEV; | |
3e2b8fbe JF |
337 | register_xenstore_notifier(&xenstore_notifier); |
338 | ||
339 | return 0; | |
340 | } | |
183d03cc | 341 | EXPORT_SYMBOL_GPL(xen_setup_shutdown_event); |
3e2b8fbe | 342 | |
702d4eb9 | 343 | subsys_initcall(xen_setup_shutdown_event); |