From 44b3c7af02ca2701b6b90ee30c9d1d9c3ae07653 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 11 Oct 2016 13:34:16 +0200 Subject: [PATCH] xenbus: advertise control feature flags The Xen docs specify several flags which a guest can set to advertise which values of the xenstore control/shutdown key it will recognize. This patch adds code to write all the relevant feature-flag keys. Based-on-patch-by: Paul Durrant Signed-off-by: Juergen Gross Reviewed-by: David Vrabel Reviewed-by: Paul Durrant Signed-off-by: David Vrabel --- drivers/xen/manage.c | 45 ++++++++++++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 16 deletions(-) diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index e12bd3635f83..26e5e8507f03 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -168,7 +168,9 @@ static void do_suspend(void) #endif /* CONFIG_HIBERNATE_CALLBACKS */ struct shutdown_handler { - const char *command; +#define SHUTDOWN_CMD_SIZE 11 + const char command[SHUTDOWN_CMD_SIZE]; + bool flag; void (*cb)(void); }; @@ -206,22 +208,22 @@ static void do_reboot(void) ctrl_alt_del(); } +static struct shutdown_handler shutdown_handlers[] = { + { "poweroff", true, do_poweroff }, + { "halt", false, do_poweroff }, + { "reboot", true, do_reboot }, +#ifdef CONFIG_HIBERNATE_CALLBACKS + { "suspend", true, do_suspend }, +#endif +}; + static void shutdown_handler(struct xenbus_watch *watch, const char **vec, unsigned int len) { char *str; struct xenbus_transaction xbt; int err; - static struct shutdown_handler handlers[] = { - { "poweroff", do_poweroff }, - { "halt", do_poweroff }, - { "reboot", do_reboot }, -#ifdef CONFIG_HIBERNATE_CALLBACKS - { "suspend", do_suspend }, -#endif - {NULL, NULL}, - }; - static struct shutdown_handler *handler; + int idx; if (shutting_down != SHUTDOWN_INVALID) return; @@ -238,13 +240,13 @@ static void shutdown_handler(struct xenbus_watch *watch, return; } - for (handler = &handlers[0]; handler->command; handler++) { - if (strcmp(str, handler->command) == 0) + for (idx = 0; idx < ARRAY_SIZE(shutdown_handlers); idx++) { + if (strcmp(str, shutdown_handlers[idx].command) == 0) break; } /* Only acknowledge commands which we are prepared to handle. */ - if (handler->cb) + if (idx < ARRAY_SIZE(shutdown_handlers)) xenbus_write(xbt, "control", "shutdown", ""); err = xenbus_transaction_end(xbt, 0); @@ -253,8 +255,8 @@ static void shutdown_handler(struct xenbus_watch *watch, goto again; } - if (handler->cb) { - handler->cb(); + if (idx < ARRAY_SIZE(shutdown_handlers)) { + shutdown_handlers[idx].cb(); } else { pr_info("Ignoring shutdown request: %s\n", str); shutting_down = SHUTDOWN_INVALID; @@ -310,6 +312,9 @@ static struct notifier_block xen_reboot_nb = { static int setup_shutdown_watcher(void) { int err; + int idx; +#define FEATURE_PATH_SIZE (SHUTDOWN_CMD_SIZE + sizeof("feature-")) + char node[FEATURE_PATH_SIZE]; err = register_xenbus_watch(&shutdown_watch); if (err) { @@ -326,6 +331,14 @@ static int setup_shutdown_watcher(void) } #endif + for (idx = 0; idx < ARRAY_SIZE(shutdown_handlers); idx++) { + if (!shutdown_handlers[idx].flag) + continue; + snprintf(node, FEATURE_PATH_SIZE, "feature-%s", + shutdown_handlers[idx].command); + xenbus_printf(XBT_NIL, "control", node, "%u", 1); + } + return 0; }