Try to unmount writable filesystems when rebooting

Ext4 filesystems like to be unmounted before rebooting.  The Android system
doesn't have a traditional Linux init setup, and shutting down the system
was not much more than calling sync(2) and reboot(2).  This adds a new
function to libcutils called android_reboot().  By default, it calls sync()
and then remounts all writable filesystems as read-only and marks them clean.
There is a flag parameter in which the caller can ask for sync() not to be
called, or to not remount the filesystems as read-only.  Then it will call
reboot(2) as directed by the other parameters.  This change also updates
adb, init and toolbox to call the new android_reboot() function.
Fixes bugs 3350709 and 3495575.

Change-Id: I16d71ffce3134310d7a260f61ec6f4dd204124a7

1 files changed, 2 insertions, 3 deletions

diff --git a/adb/services.c b/adb/services.c
index c22ce17..7eab17a 100644
--- a/adb/services.c
+++ b/adb/services.c
@@ -32,7 +32,7 @@
 #    include <netdb.h>
 #  endif
 #else
-#  include <sys/reboot.h>
+#  include <cutils/android_reboot.h>
 #endif
 
 typedef struct stinfo stinfo;
@@ -193,8 +193,7 @@ void reboot_service(int fd, void *arg)
         waitpid(pid, &ret, 0);
     }
 
-    ret = __reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2,
-                    LINUX_REBOOT_CMD_RESTART2, (char *)arg);
+    ret = android_reboot(ANDROID_RB_RESTART2, 0, (char *) arg);
     if (ret < 0) {
         snprintf(buf, sizeof(buf), "reboot failed: %s\n", strerror(errno));
         writex(fd, buf, strlen(buf));