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>
diff --git a/kernel/sys.c b/kernel/sys.c
index 4d141ae..aeded9a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2286,3 +2286,61 @@
}
return err ? -EFAULT : 0;
}
+
+char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
+
+static void argv_cleanup(char **argv, char **envp)
+{
+ argv_free(argv);
+}
+
+/**
+ * orderly_poweroff - Trigger an orderly system poweroff
+ * @force: force poweroff if command execution fails
+ *
+ * This may be called from any context to trigger a system shutdown.
+ * If the orderly shutdown fails, it will force an immediate shutdown.
+ */
+int orderly_poweroff(bool force)
+{
+ int argc;
+ char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc);
+ static char *envp[] = {
+ "HOME=/",
+ "PATH=/sbin:/bin:/usr/sbin:/usr/bin",
+ NULL
+ };
+ int ret = -ENOMEM;
+ struct subprocess_info *info;
+
+ if (argv == NULL) {
+ printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n",
+ __func__, poweroff_cmd);
+ goto out;
+ }
+
+ info = call_usermodehelper_setup(argv[0], argv, envp);
+ if (info == NULL) {
+ argv_free(argv);
+ goto out;
+ }
+
+ call_usermodehelper_setcleanup(info, argv_cleanup);
+
+ ret = call_usermodehelper_exec(info, -1);
+
+ out:
+ if (ret && force) {
+ printk(KERN_WARNING "Failed to start orderly shutdown: "
+ "forcing the issue\n");
+
+ /* I guess this should try to kick off some daemon to
+ sync and poweroff asap. Or not even bother syncing
+ if we're doing an emergency shutdown? */
+ emergency_sync();
+ kernel_power_off();
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(orderly_poweroff);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 7063ebc..44a1d69 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -46,6 +46,7 @@
#include <linux/syscalls.h>
#include <linux/nfs_fs.h>
#include <linux/acpi.h>
+#include <linux/reboot.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -705,6 +706,15 @@
.proc_handler = &proc_dointvec,
},
#endif
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "poweroff_cmd",
+ .data = &poweroff_cmd,
+ .maxlen = POWEROFF_CMD_PATH_LEN,
+ .mode = 0644,
+ .proc_handler = &proc_dostring,
+ .strategy = &sysctl_string,
+ },
{ .ctl_name = 0 }
};