Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Handle extern requests for shutdown, reboot and sysrq |
| 3 | */ |
| 4 | #include <linux/kernel.h> |
| 5 | #include <linux/err.h> |
| 6 | #include <linux/reboot.h> |
| 7 | #include <linux/sysrq.h> |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 8 | #include <linux/stop_machine.h> |
| 9 | #include <linux/freezer.h> |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 10 | |
| 11 | #include <xen/xenbus.h> |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 12 | #include <xen/grant_table.h> |
| 13 | #include <xen/events.h> |
| 14 | #include <xen/hvc-console.h> |
| 15 | #include <xen/xen-ops.h> |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 16 | |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 17 | #include <asm/xen/hypercall.h> |
| 18 | #include <asm/xen/page.h> |
| 19 | |
| 20 | enum shutdown_state { |
| 21 | SHUTDOWN_INVALID = -1, |
| 22 | SHUTDOWN_POWEROFF = 0, |
| 23 | SHUTDOWN_SUSPEND = 2, |
| 24 | /* Code 3 is SHUTDOWN_CRASH, which we don't use because the domain can only |
| 25 | report a crash, not be instructed to crash! |
| 26 | HALT is the same as POWEROFF, as far as we're concerned. The tools use |
| 27 | the distinction when we return the reason code to them. */ |
| 28 | SHUTDOWN_HALT = 4, |
| 29 | }; |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 30 | |
| 31 | /* Ignore multiple shutdown requests. */ |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 32 | static enum shutdown_state shutting_down = SHUTDOWN_INVALID; |
| 33 | |
Jeremy Fitzhardinge | c782772 | 2008-05-29 09:02:19 +0100 | [diff] [blame] | 34 | #ifdef CONFIG_PM_SLEEP |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 35 | static int xen_suspend(void *data) |
| 36 | { |
| 37 | int *cancelled = data; |
Jeremy Fitzhardinge | 359cdd3 | 2008-05-26 23:31:28 +0100 | [diff] [blame] | 38 | int err; |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 39 | |
| 40 | BUG_ON(!irqs_disabled()); |
| 41 | |
Rafael J. Wysocki | 770824b | 2009-02-22 18:38:50 +0100 | [diff] [blame] | 42 | err = sysdev_suspend(PMSG_SUSPEND); |
| 43 | if (err) { |
| 44 | printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n", |
| 45 | err); |
Magnus Damm | e39a71e | 2009-05-15 00:53:26 +0200 | [diff] [blame^] | 46 | device_resume_noirq(PMSG_RESUME); |
Rafael J. Wysocki | 770824b | 2009-02-22 18:38:50 +0100 | [diff] [blame] | 47 | return err; |
| 48 | } |
Jeremy Fitzhardinge | 359cdd3 | 2008-05-26 23:31:28 +0100 | [diff] [blame] | 49 | |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 50 | xen_mm_pin_all(); |
| 51 | gnttab_suspend(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 52 | xen_pre_suspend(); |
| 53 | |
| 54 | /* |
| 55 | * This hypercall returns 1 if suspend was cancelled |
| 56 | * or the domain was merely checkpointed, and 0 if it |
| 57 | * is resuming in a new domain. |
| 58 | */ |
| 59 | *cancelled = HYPERVISOR_suspend(virt_to_mfn(xen_start_info)); |
| 60 | |
| 61 | xen_post_suspend(*cancelled); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 62 | gnttab_resume(); |
| 63 | xen_mm_unpin_all(); |
| 64 | |
| 65 | if (!*cancelled) { |
| 66 | xen_irq_resume(); |
| 67 | xen_console_resume(); |
Isaku Yamahata | ad55db9 | 2008-07-08 15:06:32 -0700 | [diff] [blame] | 68 | xen_timer_resume(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 69 | } |
| 70 | |
Ian Campbell | 1e6fcf8 | 2009-03-25 17:46:42 +0000 | [diff] [blame] | 71 | sysdev_resume(); |
Magnus Damm | e39a71e | 2009-05-15 00:53:26 +0200 | [diff] [blame^] | 72 | device_resume_noirq(PMSG_RESUME); |
Ian Campbell | 1e6fcf8 | 2009-03-25 17:46:42 +0000 | [diff] [blame] | 73 | |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 74 | return 0; |
| 75 | } |
| 76 | |
| 77 | static void do_suspend(void) |
| 78 | { |
| 79 | int err; |
| 80 | int cancelled = 1; |
| 81 | |
| 82 | shutting_down = SHUTDOWN_SUSPEND; |
| 83 | |
| 84 | #ifdef CONFIG_PREEMPT |
| 85 | /* If the kernel is preemptible, we need to freeze all the processes |
| 86 | to prevent them from being in the middle of a pagetable update |
| 87 | during suspend. */ |
| 88 | err = freeze_processes(); |
| 89 | if (err) { |
| 90 | printk(KERN_ERR "xen suspend: freeze failed %d\n", err); |
| 91 | return; |
| 92 | } |
| 93 | #endif |
| 94 | |
| 95 | err = device_suspend(PMSG_SUSPEND); |
| 96 | if (err) { |
| 97 | printk(KERN_ERR "xen suspend: device_suspend %d\n", err); |
| 98 | goto out; |
| 99 | } |
| 100 | |
Ian Campbell | de5b31b | 2009-02-09 12:05:50 -0800 | [diff] [blame] | 101 | printk(KERN_DEBUG "suspending xenstore...\n"); |
| 102 | xs_suspend(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 103 | |
Magnus Damm | e39a71e | 2009-05-15 00:53:26 +0200 | [diff] [blame^] | 104 | err = device_suspend_noirq(PMSG_SUSPEND); |
Rafael J. Wysocki | 2ed8d2b | 2009-03-16 22:34:06 +0100 | [diff] [blame] | 105 | if (err) { |
Magnus Damm | e39a71e | 2009-05-15 00:53:26 +0200 | [diff] [blame^] | 106 | printk(KERN_ERR "device_suspend_noirq failed: %d\n", err); |
Rafael J. Wysocki | 2ed8d2b | 2009-03-16 22:34:06 +0100 | [diff] [blame] | 107 | goto resume_devices; |
| 108 | } |
| 109 | |
Rusty Russell | f7df8ed | 2009-01-10 21:58:09 -0800 | [diff] [blame] | 110 | err = stop_machine(xen_suspend, &cancelled, cpumask_of(0)); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 111 | if (err) { |
| 112 | printk(KERN_ERR "failed to start xen_suspend: %d\n", err); |
| 113 | goto out; |
| 114 | } |
| 115 | |
Isaku Yamahata | ad55db9 | 2008-07-08 15:06:32 -0700 | [diff] [blame] | 116 | if (!cancelled) { |
| 117 | xen_arch_resume(); |
Ian Campbell | de5b31b | 2009-02-09 12:05:50 -0800 | [diff] [blame] | 118 | xs_resume(); |
Isaku Yamahata | ad55db9 | 2008-07-08 15:06:32 -0700 | [diff] [blame] | 119 | } else |
Ian Campbell | de5b31b | 2009-02-09 12:05:50 -0800 | [diff] [blame] | 120 | xs_suspend_cancel(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 121 | |
Magnus Damm | e39a71e | 2009-05-15 00:53:26 +0200 | [diff] [blame^] | 122 | device_resume_noirq(PMSG_RESUME); |
Rafael J. Wysocki | 2ed8d2b | 2009-03-16 22:34:06 +0100 | [diff] [blame] | 123 | |
| 124 | resume_devices: |
Stephen Rothwell | 55ca089 | 2008-07-17 13:09:24 +1000 | [diff] [blame] | 125 | device_resume(PMSG_RESUME); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 126 | |
Jeremy Fitzhardinge | 359cdd3 | 2008-05-26 23:31:28 +0100 | [diff] [blame] | 127 | /* Make sure timer events get retriggered on all CPUs */ |
| 128 | clock_was_set(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 129 | out: |
| 130 | #ifdef CONFIG_PREEMPT |
| 131 | thaw_processes(); |
| 132 | #endif |
| 133 | shutting_down = SHUTDOWN_INVALID; |
| 134 | } |
Jeremy Fitzhardinge | c782772 | 2008-05-29 09:02:19 +0100 | [diff] [blame] | 135 | #endif /* CONFIG_PM_SLEEP */ |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 136 | |
| 137 | static void shutdown_handler(struct xenbus_watch *watch, |
| 138 | const char **vec, unsigned int len) |
| 139 | { |
| 140 | char *str; |
| 141 | struct xenbus_transaction xbt; |
| 142 | int err; |
| 143 | |
| 144 | if (shutting_down != SHUTDOWN_INVALID) |
| 145 | return; |
| 146 | |
| 147 | again: |
| 148 | err = xenbus_transaction_start(&xbt); |
| 149 | if (err) |
| 150 | return; |
| 151 | |
| 152 | str = (char *)xenbus_read(xbt, "control", "shutdown", NULL); |
| 153 | /* Ignore read errors and empty reads. */ |
| 154 | if (XENBUS_IS_ERR_READ(str)) { |
| 155 | xenbus_transaction_end(xbt, 1); |
| 156 | return; |
| 157 | } |
| 158 | |
| 159 | xenbus_write(xbt, "control", "shutdown", ""); |
| 160 | |
| 161 | err = xenbus_transaction_end(xbt, 0); |
| 162 | if (err == -EAGAIN) { |
| 163 | kfree(str); |
| 164 | goto again; |
| 165 | } |
| 166 | |
| 167 | if (strcmp(str, "poweroff") == 0 || |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 168 | strcmp(str, "halt") == 0) { |
| 169 | shutting_down = SHUTDOWN_POWEROFF; |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 170 | orderly_poweroff(false); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 171 | } else if (strcmp(str, "reboot") == 0) { |
| 172 | shutting_down = SHUTDOWN_POWEROFF; /* ? */ |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 173 | ctrl_alt_del(); |
Jeremy Fitzhardinge | 0e91398 | 2008-05-26 23:31:27 +0100 | [diff] [blame] | 174 | #ifdef CONFIG_PM_SLEEP |
| 175 | } else if (strcmp(str, "suspend") == 0) { |
| 176 | do_suspend(); |
| 177 | #endif |
| 178 | } else { |
Jeremy Fitzhardinge | 3e2b8fb | 2007-07-17 18:37:07 -0700 | [diff] [blame] | 179 | printk(KERN_INFO "Ignoring shutdown request: %s\n", str); |
| 180 | shutting_down = SHUTDOWN_INVALID; |
| 181 | } |
| 182 | |
| 183 | kfree(str); |
| 184 | } |
| 185 | |
| 186 | static void sysrq_handler(struct xenbus_watch *watch, const char **vec, |
| 187 | unsigned int len) |
| 188 | { |
| 189 | char sysrq_key = '\0'; |
| 190 | struct xenbus_transaction xbt; |
| 191 | int err; |
| 192 | |
| 193 | again: |
| 194 | err = xenbus_transaction_start(&xbt); |
| 195 | if (err) |
| 196 | return; |
| 197 | if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) { |
| 198 | printk(KERN_ERR "Unable to read sysrq code in " |
| 199 | "control/sysrq\n"); |
| 200 | xenbus_transaction_end(xbt, 1); |
| 201 | return; |
| 202 | } |
| 203 | |
| 204 | if (sysrq_key != '\0') |
| 205 | xenbus_printf(xbt, "control", "sysrq", "%c", '\0'); |
| 206 | |
| 207 | err = xenbus_transaction_end(xbt, 0); |
| 208 | if (err == -EAGAIN) |
| 209 | goto again; |
| 210 | |
| 211 | if (sysrq_key != '\0') |
| 212 | handle_sysrq(sysrq_key, NULL); |
| 213 | } |
| 214 | |
| 215 | static struct xenbus_watch shutdown_watch = { |
| 216 | .node = "control/shutdown", |
| 217 | .callback = shutdown_handler |
| 218 | }; |
| 219 | |
| 220 | static struct xenbus_watch sysrq_watch = { |
| 221 | .node = "control/sysrq", |
| 222 | .callback = sysrq_handler |
| 223 | }; |
| 224 | |
| 225 | static int setup_shutdown_watcher(void) |
| 226 | { |
| 227 | int err; |
| 228 | |
| 229 | err = register_xenbus_watch(&shutdown_watch); |
| 230 | if (err) { |
| 231 | printk(KERN_ERR "Failed to set shutdown watcher\n"); |
| 232 | return err; |
| 233 | } |
| 234 | |
| 235 | err = register_xenbus_watch(&sysrq_watch); |
| 236 | if (err) { |
| 237 | printk(KERN_ERR "Failed to set sysrq watcher\n"); |
| 238 | return err; |
| 239 | } |
| 240 | |
| 241 | return 0; |
| 242 | } |
| 243 | |
| 244 | static int shutdown_event(struct notifier_block *notifier, |
| 245 | unsigned long event, |
| 246 | void *data) |
| 247 | { |
| 248 | setup_shutdown_watcher(); |
| 249 | return NOTIFY_DONE; |
| 250 | } |
| 251 | |
| 252 | static int __init setup_shutdown_event(void) |
| 253 | { |
| 254 | static struct notifier_block xenstore_notifier = { |
| 255 | .notifier_call = shutdown_event |
| 256 | }; |
| 257 | register_xenstore_notifier(&xenstore_notifier); |
| 258 | |
| 259 | return 0; |
| 260 | } |
| 261 | |
| 262 | subsys_initcall(setup_shutdown_event); |