diff options
Diffstat (limited to 'arch/i386/xen')
| -rw-r--r-- | arch/i386/xen/Makefile | 2 | ||||
| -rw-r--r-- | arch/i386/xen/manage.c | 143 |
2 files changed, 144 insertions, 1 deletions
diff --git a/arch/i386/xen/Makefile b/arch/i386/xen/Makefile index fd05f243a3f..7bf2ce399a2 100644 --- a/arch/i386/xen/Makefile +++ b/arch/i386/xen/Makefile @@ -1,4 +1,4 @@ obj-y := enlighten.o setup.o features.o multicalls.o mmu.o \ - events.o time.o + events.o time.o manage.o obj-$(CONFIG_SMP) += smp.o diff --git a/arch/i386/xen/manage.c b/arch/i386/xen/manage.c new file mode 100644 index 00000000000..aa7af9e6abc --- /dev/null +++ b/arch/i386/xen/manage.c @@ -0,0 +1,143 @@ +/* + * Handle extern requests for shutdown, reboot and sysrq + */ +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/reboot.h> +#include <linux/sysrq.h> + +#include <xen/xenbus.h> + +#define SHUTDOWN_INVALID -1 +#define SHUTDOWN_POWEROFF 0 +#define SHUTDOWN_SUSPEND 2 +/* Code 3 is SHUTDOWN_CRASH, which we don't use because the domain can only + * report a crash, not be instructed to crash! + * HALT is the same as POWEROFF, as far as we're concerned. The tools use + * the distinction when we return the reason code to them. + */ +#define SHUTDOWN_HALT 4 + +/* Ignore multiple shutdown requests. */ +static int shutting_down = SHUTDOWN_INVALID; + +static void shutdown_handler(struct xenbus_watch *watch, + const char **vec, unsigned int len) +{ + char *str; + struct xenbus_transaction xbt; + int err; + + if (shutting_down != SHUTDOWN_INVALID) + return; + + again: + err = xenbus_transaction_start(&xbt); + if (err) + return; + + str = (char *)xenbus_read(xbt, "control", "shutdown", NULL); + /* Ignore read errors and empty reads. */ + if (XENBUS_IS_ERR_READ(str)) { + xenbus_transaction_end(xbt, 1); + return; + } + + xenbus_write(xbt, "control", "shutdown", ""); + + err = xenbus_transaction_end(xbt, 0); + if (err == -EAGAIN) { + kfree(str); + goto again; + } + + if (strcmp(str, "poweroff") == 0 || + strcmp(str, "halt") == 0) + orderly_poweroff(false); + else if (strcmp(str, "reboot") == 0) + ctrl_alt_del(); + else { + printk(KERN_INFO "Ignoring shutdown request: %s\n", str); + shutting_down = SHUTDOWN_INVALID; + } + + kfree(str); +} + +static void sysrq_handler(struct xenbus_watch *watch, const char **vec, + unsigned int len) +{ + char sysrq_key = '\0'; + struct xenbus_transaction xbt; + int err; + + again: + err = xenbus_transaction_start(&xbt); + if (err) + return; + if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) { + printk(KERN_ERR "Unable to read sysrq code in " + "control/sysrq\n"); + xenbus_transaction_end(xbt, 1); + return; + } + + if (sysrq_key != '\0') + xenbus_printf(xbt, "control", "sysrq", "%c", '\0'); + + err = xenbus_transaction_end(xbt, 0); + if (err == -EAGAIN) + goto again; + + if (sysrq_key != '\0') + handle_sysrq(sysrq_key, NULL); +} + +static struct xenbus_watch shutdown_watch = { + .node = "control/shutdown", + .callback = shutdown_handler +}; + +static struct xenbus_watch sysrq_watch = { + .node = "control/sysrq", + .callback = sysrq_handler +}; + +static int setup_shutdown_watcher(void) +{ + int err; + + err = register_xenbus_watch(&shutdown_watch); + if (err) { + printk(KERN_ERR "Failed to set shutdown watcher\n"); + return err; + } + + err = register_xenbus_watch(&sysrq_watch); + if (err) { + printk(KERN_ERR "Failed to set sysrq watcher\n"); + return err; + } + + return 0; +} + +static int shutdown_event(struct notifier_block *notifier, + unsigned long event, + void *data) +{ + setup_shutdown_watcher(); + return NOTIFY_DONE; +} + +static int __init setup_shutdown_event(void) +{ + static struct notifier_block xenstore_notifier = { + .notifier_call = shutdown_event + }; + register_xenstore_notifier(&xenstore_notifier); + + return 0; +} + +subsys_initcall(setup_shutdown_event); |