Add common orderly_poweroff()

Various pieces of code around the kernel want to be able to trigger an
orderly poweroff.  This pulls them together into a single
implementation.

By default the poweroff command is /sbin/poweroff, but it can be set
via sysctl: kernel/poweroff_cmd.  This is split at whitespace, so it
can include command-line arguments.

This patch replaces four other instances of invoking either "poweroff"
or "shutdown -h now": two sbus drivers, and acpi thermal
management.

sparc64 has its own "powerd"; still need to determine whether it should
be replaced by orderly_poweroff().

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: Len Brown <lenb@kernel.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 30 deletions

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 88a6fc7fd271..58f1338981bc 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -40,6 +40,7 @@
 #include <linux/jiffies.h>
 #include <linux/kmod.h>
 #include <linux/seq_file.h>
+#include <linux/reboot.h>
 #include <asm/uaccess.h>
 
 #include <acpi/acpi_bus.h>
@@ -59,7 +60,6 @@
 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
 #define ACPI_THERMAL_MODE_ACTIVE	0x00
-#define ACPI_THERMAL_PATH_POWEROFF	"/sbin/poweroff"
 
 #define ACPI_THERMAL_MAX_ACTIVE	10
 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
@@ -419,26 +419,6 @@ static int acpi_thermal_get_devices(struct acpi_thermal *tz)
 	return 0;
 }
 
-static int acpi_thermal_call_usermode(char *path)
-{
-	char *argv[2] = { NULL, NULL };
-	char *envp[3] = { NULL, NULL, NULL };
-
-
-	if (!path)
-		return -EINVAL;
-
-	argv[0] = path;
-
-	/* minimal command environment */
-	envp[0] = "HOME=/";
-	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
-
-	call_usermodehelper(argv[0], argv, envp, 0);
-
-	return 0;
-}
-
 static int acpi_thermal_critical(struct acpi_thermal *tz)
 {
 	if (!tz || !tz->trips.critical.flags.valid)
@@ -456,7 +436,7 @@ static int acpi_thermal_critical(struct acpi_thermal *tz)
 	acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_CRITICAL,
 				tz->trips.critical.flags.enabled);
 
-	acpi_thermal_call_usermode(ACPI_THERMAL_PATH_POWEROFF);
+	orderly_poweroff(true);
 
 	return 0;
 }
diff --git a/drivers/sbus/char/bbc_envctrl.c b/drivers/sbus/char/bbc_envctrl.c
index a54e4140683a..e821a155b658 100644
--- a/drivers/sbus/char/bbc_envctrl.c
+++ b/drivers/sbus/char/bbc_envctrl.c
@@ -7,6 +7,7 @@
 #include <linux/kthread.h>
 #include <linux/delay.h>
 #include <linux/kmod.h>
+#include <linux/reboot.h>
 #include <asm/oplib.h>
 #include <asm/ebus.h>
 
@@ -170,8 +171,6 @@ static void get_current_temps(struct bbc_cpu_temperature *tp)
 static void do_envctrl_shutdown(struct bbc_cpu_temperature *tp)
 {
 	static int shutting_down = 0;
-	static char *envp[] = { "HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
-	char *argv[] = { "/sbin/shutdown", "-h", "now", NULL };
 	char *type = "???";
 	s8 val = -1;
 
@@ -195,7 +194,7 @@ static void do_envctrl_shutdown(struct bbc_cpu_temperature *tp)
 	printk(KERN_CRIT "kenvctrld: Shutting down the system now.\n");
 
 	shutting_down = 1;
-	if (call_usermodehelper("/sbin/shutdown", argv, envp, 0) < 0)
+	if (orderly_poweroff(true) < 0)
 		printk(KERN_CRIT "envctrl: shutdown execution failed\n");
 }
 
diff --git a/drivers/sbus/char/envctrl.c b/drivers/sbus/char/envctrl.c
index 8328acab47fd..dadabef116b6 100644
--- a/drivers/sbus/char/envctrl.c
+++ b/drivers/sbus/char/envctrl.c
@@ -26,6 +26,7 @@
 #include <linux/ioport.h>
 #include <linux/miscdevice.h>
 #include <linux/kmod.h>
+#include <linux/reboot.h>
 
 #include <asm/ebus.h>
 #include <asm/uaccess.h>
@@ -966,10 +967,6 @@ static struct i2c_child_t *envctrl_get_i2c_child(unsigned char mon_type)
 static void envctrl_do_shutdown(void)
 {
 	static int inprog = 0;
-	static char *envp[] = {	
-		"HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
-	char *argv[] = { 
-		"/sbin/shutdown", "-h", "now", NULL };	
 	int ret;
 
 	if (inprog != 0)
@@ -977,7 +974,7 @@ static void envctrl_do_shutdown(void)
 
 	inprog = 1;
 	printk(KERN_CRIT "kenvctrld: WARNING: Shutting down the system now.\n");
-	ret = call_usermodehelper("/sbin/shutdown", argv, envp, 0);
+	ret = orderly_poweroff(true);
 	if (ret < 0) {
 		printk(KERN_CRIT "kenvctrld: WARNING: system shutdown failed!\n"); 
 		inprog = 0;  /* unlikely to succeed, but we could try again */