From ec9b2065d4d3b797604c09a569083dd9ff951b1b Mon Sep 17 00:00:00 2001 From: Isaku Yamahata Date: Mon, 26 May 2008 23:31:13 +0100 Subject: xen: Move manage.c to drivers/xen for ia64/xen support move arch/x86/xen/manage.c under drivers/xen/to share codes with x86 and ia64. ia64/xen also uses manage.c Signed-off-by: Isaku Yamahata Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- drivers/xen/manage.c | 143 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) create mode 100644 drivers/xen/manage.c (limited to 'drivers/xen/manage.c') diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c new file mode 100644 index 000000000000..aa7af9e6abc0 --- /dev/null +++ b/drivers/xen/manage.c @@ -0,0 +1,143 @@ +/* + * Handle extern requests for shutdown, reboot and sysrq + */ +#include +#include +#include +#include + +#include + +#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); -- cgit v1.2.1 From 0e91398f2a5d4eb6b07df8115917d0d1cf3e9b58 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 23:31:27 +0100 Subject: xen: implement save/restore This patch implements Xen save/restore and migration. Saving is triggered via xenbus, which is polled in drivers/xen/manage.c. When a suspend request comes in, the kernel prepares itself for saving by: 1 - Freeze all processes. This is primarily to prevent any partially-completed pagetable updates from confusing the suspend process. If CONFIG_PREEMPT isn't defined, then this isn't necessary. 2 - Suspend xenbus and other devices 3 - Stop_machine, to make sure all the other vcpus are quiescent. The Xen tools require the domain to run its save off vcpu0. 4 - Within the stop_machine state, it pins any unpinned pgds (under construction or destruction), performs canonicalizes various other pieces of state (mostly converting mfns to pfns), and finally 5 - Suspend the domain Restore reverses the steps used to save the domain, ending when all the frozen processes are thawed. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- drivers/xen/manage.c | 126 +++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 112 insertions(+), 14 deletions(-) (limited to 'drivers/xen/manage.c') diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index aa7af9e6abc0..ba85fa2cff33 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -5,21 +5,113 @@ #include #include #include +#include +#include #include - -#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 +#include +#include +#include +#include + +#include +#include + +enum shutdown_state { + SHUTDOWN_INVALID = -1, + SHUTDOWN_POWEROFF = 0, + 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. */ + SHUTDOWN_HALT = 4, +}; /* Ignore multiple shutdown requests. */ -static int shutting_down = SHUTDOWN_INVALID; +static enum shutdown_state shutting_down = SHUTDOWN_INVALID; + +static int xen_suspend(void *data) +{ + int *cancelled = data; + + BUG_ON(!irqs_disabled()); + + load_cr3(swapper_pg_dir); + + xen_mm_pin_all(); + gnttab_suspend(); + xen_time_suspend(); + xen_pre_suspend(); + + /* + * This hypercall returns 1 if suspend was cancelled + * or the domain was merely checkpointed, and 0 if it + * is resuming in a new domain. + */ + *cancelled = HYPERVISOR_suspend(virt_to_mfn(xen_start_info)); + + xen_post_suspend(*cancelled); + xen_time_resume(); + gnttab_resume(); + xen_mm_unpin_all(); + + if (!*cancelled) { + xen_irq_resume(); + xen_console_resume(); + } + + return 0; +} + +static void do_suspend(void) +{ + int err; + int cancelled = 1; + + shutting_down = SHUTDOWN_SUSPEND; + +#ifdef CONFIG_PREEMPT + /* If the kernel is preemptible, we need to freeze all the processes + to prevent them from being in the middle of a pagetable update + during suspend. */ + err = freeze_processes(); + if (err) { + printk(KERN_ERR "xen suspend: freeze failed %d\n", err); + return; + } +#endif + + err = device_suspend(PMSG_SUSPEND); + if (err) { + printk(KERN_ERR "xen suspend: device_suspend %d\n", err); + goto out; + } + + printk("suspending xenbus...\n"); + /* XXX use normal device tree? */ + xenbus_suspend(); + + err = stop_machine_run(xen_suspend, &cancelled, 0); + if (err) { + printk(KERN_ERR "failed to start xen_suspend: %d\n", err); + goto out; + } + + if (!cancelled) + xenbus_resume(); + else + xenbus_suspend_cancel(); + + device_resume(); + + +out: +#ifdef CONFIG_PREEMPT + thaw_processes(); +#endif + shutting_down = SHUTDOWN_INVALID; +} static void shutdown_handler(struct xenbus_watch *watch, const char **vec, unsigned int len) @@ -52,11 +144,17 @@ static void shutdown_handler(struct xenbus_watch *watch, } if (strcmp(str, "poweroff") == 0 || - strcmp(str, "halt") == 0) + strcmp(str, "halt") == 0) { + shutting_down = SHUTDOWN_POWEROFF; orderly_poweroff(false); - else if (strcmp(str, "reboot") == 0) + } else if (strcmp(str, "reboot") == 0) { + shutting_down = SHUTDOWN_POWEROFF; /* ? */ ctrl_alt_del(); - else { +#ifdef CONFIG_PM_SLEEP + } else if (strcmp(str, "suspend") == 0) { + do_suspend(); +#endif + } else { printk(KERN_INFO "Ignoring shutdown request: %s\n", str); shutting_down = SHUTDOWN_INVALID; } -- cgit v1.2.1 From 359cdd3f866b6219a6729e313faf2221397f3278 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 23:31:28 +0100 Subject: xen: maintain clock offset over save/restore Hook into the device model to make sure that timekeeping's resume handler is called. This deals with our clocksource's non-monotonicity over the save/restore. Explicitly call clock_has_changed() to make sure that all the timers get retriggered properly. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- drivers/xen/manage.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/xen/manage.c') diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index ba85fa2cff33..675c3dd23962 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -34,14 +34,21 @@ static enum shutdown_state shutting_down = SHUTDOWN_INVALID; static int xen_suspend(void *data) { int *cancelled = data; + int err; BUG_ON(!irqs_disabled()); load_cr3(swapper_pg_dir); + err = device_power_down(PMSG_SUSPEND); + if (err) { + printk(KERN_ERR "xen_suspend: device_power_down failed: %d\n", + err); + return err; + } + xen_mm_pin_all(); gnttab_suspend(); - xen_time_suspend(); xen_pre_suspend(); /* @@ -52,10 +59,11 @@ static int xen_suspend(void *data) *cancelled = HYPERVISOR_suspend(virt_to_mfn(xen_start_info)); xen_post_suspend(*cancelled); - xen_time_resume(); gnttab_resume(); xen_mm_unpin_all(); + device_power_up(); + if (!*cancelled) { xen_irq_resume(); xen_console_resume(); @@ -105,7 +113,8 @@ static void do_suspend(void) device_resume(); - + /* Make sure timer events get retriggered on all CPUs */ + clock_was_set(); out: #ifdef CONFIG_PREEMPT thaw_processes(); -- cgit v1.2.1 From c78277288e3d561d55fb48bc0fe8d6e2cf4d0880 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 29 May 2008 09:02:19 +0100 Subject: CONFIG_PM_SLEEP fix: xen: fix compilation when CONFIG_PM_SLEEP is disabled Xen save/restore depends on CONFIG_PM_SLEEP being set for device_power_up/down. Signed-off-by: Jeremy Fitzhardinge Acked-by: Randy Dunlap Signed-off-by: Ingo Molnar --- drivers/xen/manage.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/xen/manage.c') diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index 675c3dd23962..5b546e365f00 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -31,6 +31,7 @@ enum shutdown_state { /* Ignore multiple shutdown requests. */ static enum shutdown_state shutting_down = SHUTDOWN_INVALID; +#ifdef CONFIG_PM_SLEEP static int xen_suspend(void *data) { int *cancelled = data; @@ -121,6 +122,7 @@ out: #endif shutting_down = SHUTDOWN_INVALID; } +#endif /* CONFIG_PM_SLEEP */ static void shutdown_handler(struct xenbus_watch *watch, const char **vec, unsigned int len) -- cgit v1.2.1