1 files changed, 79 insertions, 12 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index 4d141ae3e802..08562f419768 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -100,6 +100,13 @@ struct pid *cad_pid;
 EXPORT_SYMBOL(cad_pid);
 
 /*
+ * If set, this is used for preparing the system to power off.
+ */
+
+void (*pm_power_off_prepare)(void);
+EXPORT_SYMBOL(pm_power_off_prepare);
+
+/*
  *	Notifier list for kernel code which wants to be called
  *	at shutdown. This is used to stop any idling DMA operations
  *	and the like. 
@@ -867,6 +874,8 @@ EXPORT_SYMBOL_GPL(kernel_halt);
 void kernel_power_off(void)
 {
 	kernel_shutdown_prepare(SYSTEM_POWER_OFF);
+	if (pm_power_off_prepare)
+		pm_power_off_prepare();
 	printk(KERN_EMERG "Power down.\n");
 	machine_power_off();
 }
@@ -1027,7 +1036,7 @@ asmlinkage long sys_setregid(gid_t rgid, gid_t egid)
 			return -EPERM;
 	}
 	if (new_egid != old_egid) {
-		current->mm->dumpable = suid_dumpable;
+		set_dumpable(current->mm, suid_dumpable);
 		smp_wmb();
 	}
 	if (rgid != (gid_t) -1 ||
@@ -1057,13 +1066,13 @@ asmlinkage long sys_setgid(gid_t gid)
 
 	if (capable(CAP_SETGID)) {
 		if (old_egid != gid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->gid = current->egid = current->sgid = current->fsgid = gid;
 	} else if ((gid == current->gid) || (gid == current->sgid)) {
 		if (old_egid != gid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->egid = current->fsgid = gid;
@@ -1094,7 +1103,7 @@ static int set_user(uid_t new_ruid, int dumpclear)
 	switch_uid(new_user);
 
 	if (dumpclear) {
-		current->mm->dumpable = suid_dumpable;
+		set_dumpable(current->mm, suid_dumpable);
 		smp_wmb();
 	}
 	current->uid = new_ruid;
@@ -1150,7 +1159,7 @@ asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
 		return -EAGAIN;
 
 	if (new_euid != old_euid) {
-		current->mm->dumpable = suid_dumpable;
+		set_dumpable(current->mm, suid_dumpable);
 		smp_wmb();
 	}
 	current->fsuid = current->euid = new_euid;
@@ -1200,7 +1209,7 @@ asmlinkage long sys_setuid(uid_t uid)
 		return -EPERM;
 
 	if (old_euid != uid) {
-		current->mm->dumpable = suid_dumpable;
+		set_dumpable(current->mm, suid_dumpable);
 		smp_wmb();
 	}
 	current->fsuid = current->euid = uid;
@@ -1245,7 +1254,7 @@ asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
 	}
 	if (euid != (uid_t) -1) {
 		if (euid != current->euid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->euid = euid;
@@ -1295,7 +1304,7 @@ asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
 	}
 	if (egid != (gid_t) -1) {
 		if (egid != current->egid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->egid = egid;
@@ -1341,7 +1350,7 @@ asmlinkage long sys_setfsuid(uid_t uid)
 	    uid == current->suid || uid == current->fsuid || 
 	    capable(CAP_SETUID)) {
 		if (uid != old_fsuid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->fsuid = uid;
@@ -1370,7 +1379,7 @@ asmlinkage long sys_setfsgid(gid_t gid)
 	    gid == current->sgid || gid == current->fsgid || 
 	    capable(CAP_SETGID)) {
 		if (gid != old_fsgid) {
-			current->mm->dumpable = suid_dumpable;
+			set_dumpable(current->mm, suid_dumpable);
 			smp_wmb();
 		}
 		current->fsgid = gid;
@@ -2167,14 +2176,14 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
 			error = put_user(current->pdeath_signal, (int __user *)arg2);
 			break;
 		case PR_GET_DUMPABLE:
-			error = current->mm->dumpable;
+			error = get_dumpable(current->mm);
 			break;
 		case PR_SET_DUMPABLE:
 			if (arg2 < 0 || arg2 > 1) {
 				error = -EINVAL;
 				break;
 			}
-			current->mm->dumpable = arg2;
+			set_dumpable(current->mm, arg2);
 			break;
 
 		case PR_SET_UNALIGN:
@@ -2286,3 +2295,61 @@ asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep,
 	}
 	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, UMH_NO_WAIT);
+
+  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);