Use fsck.f2fs -a instead of -f for faster boot
and run fsck with -f on clean shutdown instead.
With -f, fsck.f2fs always performs a full scan of the /data
partition regardless of whether the partition is clean or not.
The full scan takes more than 2 seconds on volantis-userdebug
and delays the OS boot.
With -a, the command does almost nothing when the partition
is clean and finishes within 20-30ms on volantis-userdebug.
When the partition has an error or its check point has
CP_FSCK_FLAG (aka "need_fsck"), the command does exactly the
same full scan as -f to fix it.
Bug: 21853106
Change-Id: I126263caf34c0f5bb8f5e6794454d4e72526ce38
diff --git a/init/builtins.cpp b/init/builtins.cpp
index ca31c50..d5d3faf 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -16,7 +16,9 @@
#include <errno.h>
#include <fcntl.h>
+#include <mntent.h>
#include <net/if.h>
+#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -38,6 +40,7 @@
#include <base/stringprintf.h>
#include <cutils/partition_utils.h>
#include <cutils/android_reboot.h>
+#include <logwrap/logwrap.h>
#include <private/android_filesystem_config.h>
#include "init.h"
@@ -49,6 +52,8 @@
#include "log.h"
#define chmod DO_NOT_USE_CHMOD_USE_FCHMODAT_SYMLINK_NOFOLLOW
+#define UNMOUNT_CHECK_MS 5000
+#define UNMOUNT_CHECK_TIMES 10
int add_environment(const char *name, const char *value);
@@ -109,6 +114,67 @@
}
}
+static void unmount_and_fsck(const struct mntent *entry)
+{
+ if (strcmp(entry->mnt_type, "f2fs") && strcmp(entry->mnt_type, "ext4"))
+ return;
+
+ /* First, lazily unmount the directory. This unmount request finishes when
+ * all processes that open a file or directory in |entry->mnt_dir| exit.
+ */
+ TEMP_FAILURE_RETRY(umount2(entry->mnt_dir, MNT_DETACH));
+
+ /* Next, kill all processes except init, kthreadd, and kthreadd's
+ * children to finish the lazy unmount. Killing all processes here is okay
+ * because this callback function is only called right before reboot().
+ * It might be cleaner to selectively kill processes that actually use
+ * |entry->mnt_dir| rather than killing all, probably by reusing a function
+ * like killProcessesWithOpenFiles() in vold/, but the selinux policy does
+ * not allow init to scan /proc/<pid> files which the utility function
+ * heavily relies on. The policy does not allow the process to execute
+ * killall/pkill binaries either. Note that some processes might
+ * automatically restart after kill(), but that is not really a problem
+ * because |entry->mnt_dir| is no longer visible to such new processes.
+ */
+ service_for_each(service_stop);
+ TEMP_FAILURE_RETRY(kill(-1, SIGKILL));
+
+ int count = 0;
+ while (count++ < UNMOUNT_CHECK_TIMES) {
+ int fd = TEMP_FAILURE_RETRY(open(entry->mnt_fsname, O_RDONLY | O_EXCL));
+ if (fd >= 0) {
+ /* |entry->mnt_dir| has sucessfully been unmounted. */
+ close(fd);
+ break;
+ } else if (errno == EBUSY) {
+ /* Some processes using |entry->mnt_dir| are still alive. Wait for a
+ * while then retry.
+ */
+ TEMP_FAILURE_RETRY(
+ usleep(UNMOUNT_CHECK_MS * 1000 / UNMOUNT_CHECK_TIMES));
+ continue;
+ } else {
+ /* Cannot open the device. Give up. */
+ return;
+ }
+ }
+
+ int st;
+ if (!strcmp(entry->mnt_type, "f2fs")) {
+ const char *f2fs_argv[] = {
+ "/system/bin/fsck.f2fs", "-f", entry->mnt_fsname,
+ };
+ android_fork_execvp_ext(ARRAY_SIZE(f2fs_argv), (char **)f2fs_argv,
+ &st, true, LOG_KLOG, true, NULL);
+ } else if (!strcmp(entry->mnt_type, "ext4")) {
+ const char *ext4_argv[] = {
+ "/system/bin/e2fsck", "-f", "-y", entry->mnt_fsname,
+ };
+ android_fork_execvp_ext(ARRAY_SIZE(ext4_argv), (char **)ext4_argv,
+ &st, true, LOG_KLOG, true, NULL);
+ }
+}
+
int do_class_start(int nargs, char **args)
{
/* Starting a class does not start services
@@ -559,6 +625,7 @@
int len = 0;
int cmd = 0;
const char *reboot_target;
+ void (*callback_on_ro_remount)(const struct mntent*) = NULL;
res = expand_props(command, args[1], sizeof(command));
if (res) {
@@ -569,6 +636,7 @@
if (strncmp(command, "shutdown", 8) == 0) {
cmd = ANDROID_RB_POWEROFF;
len = 8;
+ callback_on_ro_remount = unmount_and_fsck;
} else if (strncmp(command, "reboot", 6) == 0) {
cmd = ANDROID_RB_RESTART2;
len = 6;
@@ -586,7 +654,8 @@
return -EINVAL;
}
- return android_reboot(cmd, 0, reboot_target);
+ return android_reboot_with_callback(cmd, 0, reboot_target,
+ callback_on_ro_remount);
}
int do_trigger(int nargs, char **args)