diff --git a/init/builtins.cpp b/init/builtins.cpp
index 2f2ead0..b2c6461 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -42,6 +42,8 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+#include <memory>
+
 #include <ApexProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
@@ -627,6 +629,8 @@
     return Error() << "Invalid code: " << code;
 }
 
+static int initial_mount_fstab_return_code = -1;
+
 /* mount_all <fstab> [ <path> ]* [--<options>]*
  *
  * This function might request a reboot, in which case it will
@@ -662,6 +666,7 @@
     if (!ReadFstabFromFile(fstab_file, &fstab)) {
         return Error() << "Could not read fstab";
     }
+
     auto mount_fstab_return_code = fs_mgr_mount_all(&fstab, mount_mode);
     property_set(prop_name, std::to_string(t.duration().count()));
 
@@ -673,6 +678,7 @@
     if (queue_event) {
         /* queue_fs_event will queue event based on mount_fstab return code
          * and return processed return code*/
+        initial_mount_fstab_return_code = mount_fstab_return_code;
         auto queue_fs_result = queue_fs_event(mount_fstab_return_code);
         if (!queue_fs_result) {
             return Error() << "queue_fs_event() failed: " << queue_fs_result.error();
@@ -1132,6 +1138,25 @@
     return ExecWithFunctionOnFailure(args, reboot);
 }
 
+static Result<void> do_remount_userdata(const BuiltinArguments& args) {
+    if (initial_mount_fstab_return_code == -1) {
+        return Error() << "Calling remount_userdata too early";
+    }
+    Fstab fstab;
+    if (!ReadDefaultFstab(&fstab)) {
+        // TODO(b/135984674): should we reboot here?
+        return Error() << "Failed to read fstab";
+    }
+    // TODO(b/135984674): check that fstab contains /data.
+    if (auto rc = fs_mgr_remount_userdata_into_checkpointing(&fstab); rc < 0) {
+        TriggerShutdown("reboot,mount-userdata-failed");
+    }
+    if (auto result = queue_fs_event(initial_mount_fstab_return_code); !result) {
+        return Error() << "queue_fs_event() failed: " << result.error();
+    }
+    return {};
+}
+
 static Result<void> do_installkey(const BuiltinArguments& args) {
     if (!is_file_crypto()) return {};
 
@@ -1243,6 +1268,7 @@
         {"umount",                  {1,     1,    {false,  do_umount}}},
         {"umount_all",              {1,     1,    {false,  do_umount_all}}},
         {"readahead",               {1,     2,    {true,   do_readahead}}},
+        {"remount_userdata",        {0,     0,    {false,  do_remount_userdata}}},
         {"restart",                 {1,     1,    {false,  do_restart}}},
         {"restorecon",              {1,     kMax, {true,   do_restorecon}}},
         {"restorecon_recursive",    {1,     kMax, {true,   do_restorecon_recursive}}},
diff --git a/init/reboot.cpp b/init/reboot.cpp
index d77b975..f2e260e 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -181,10 +181,17 @@
     }
 }
 
-static void ShutdownVold() {
+static Result<void> ShutdownVold() {
     const char* vdc_argv[] = {"/system/bin/vdc", "volume", "shutdown"};
     int status;
-    logwrap_fork_execvp(arraysize(vdc_argv), vdc_argv, &status, false, LOG_KLOG, true, nullptr);
+    if (logwrap_fork_execvp(arraysize(vdc_argv), vdc_argv, &status, false, LOG_KLOG, true,
+                            nullptr) != 0) {
+        return ErrnoError() << "Failed to call 'vdc volume shutdown'";
+    }
+    if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
+        return {};
+    }
+    return Error() << "'vdc volume shutdown' failed : " << status;
 }
 
 static void LogShutdownTime(UmountStat stat, Timer* t) {
@@ -426,11 +433,11 @@
 #define ZRAM_DEVICE   "/dev/block/zram0"
 #define ZRAM_RESET    "/sys/block/zram0/reset"
 #define ZRAM_BACK_DEV "/sys/block/zram0/backing_dev"
-static void KillZramBackingDevice() {
+static Result<void> KillZramBackingDevice() {
     std::string backing_dev;
-    if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) return;
+    if (!android::base::ReadFileToString(ZRAM_BACK_DEV, &backing_dev)) return {};
 
-    if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) return;
+    if (!android::base::StartsWith(backing_dev, "/dev/block/loop")) return {};
 
     // cut the last "\n"
     backing_dev.erase(backing_dev.length() - 1);
@@ -439,28 +446,29 @@
     Timer swap_timer;
     LOG(INFO) << "swapoff() start...";
     if (swapoff(ZRAM_DEVICE) == -1) {
-        LOG(ERROR) << "zram_backing_dev: swapoff (" << backing_dev << ")" << " failed";
-        return;
+        return ErrnoError() << "zram_backing_dev: swapoff (" << backing_dev << ")"
+                            << " failed";
     }
     LOG(INFO) << "swapoff() took " << swap_timer;;
 
     if (!WriteStringToFile("1", ZRAM_RESET)) {
-        LOG(ERROR) << "zram_backing_dev: reset (" << backing_dev << ")" << " failed";
-        return;
+        return Error() << "zram_backing_dev: reset (" << backing_dev << ")"
+                       << " failed";
     }
 
     // clear loopback device
     unique_fd loop(TEMP_FAILURE_RETRY(open(backing_dev.c_str(), O_RDWR | O_CLOEXEC)));
     if (loop.get() < 0) {
-        LOG(ERROR) << "zram_backing_dev: open(" << backing_dev << ")" << " failed";
-        return;
+        return ErrnoError() << "zram_backing_dev: open(" << backing_dev << ")"
+                            << " failed";
     }
 
     if (ioctl(loop.get(), LOOP_CLR_FD, 0) < 0) {
-        LOG(ERROR) << "zram_backing_dev: loop_clear (" << backing_dev << ")" << " failed";
-        return;
+        return ErrnoError() << "zram_backing_dev: loop_clear (" << backing_dev << ")"
+                            << " failed";
     }
     LOG(INFO) << "zram_backing_dev: `" << backing_dev << "` is cleared successfully.";
+    return {};
 }
 
 // Stops given services, waits for them to be stopped for |timeout| ms.
@@ -738,7 +746,23 @@
         // TODO(b/135984674): store information about offending services for debugging.
         return Error() << r << " post-data services are still running";
     }
-    // TODO(b/135984674): remount userdata
+    // We only really need to restart vold if userdata is ext4 filesystem.
+    // TODO(b/135984674): get userdata fs type here, and do nothing in case of f2fs.
+    // First shutdown volumes managed by vold. They will be recreated by
+    // system_server.
+    Service* vold_service = ServiceList::GetInstance().FindService("vold");
+    if (vold_service != nullptr && vold_service->IsRunning()) {
+        if (auto result = ShutdownVold(); !result) {
+            return result;
+        }
+        LOG(INFO) << "Restarting vold";
+        vold_service->Restart();
+    }
+    // Again, we only need to kill zram backing device in case of ext4 userdata.
+    // TODO(b/135984674): get userdata fs type here, and do nothing in case of f2fs.
+    if (auto result = KillZramBackingDevice(); !result) {
+        return result;
+    }
     if (int r = StopServicesAndLogViolations(GetDebuggingServices(true /* only_post_data */), 5s,
                                              false /* SIGKILL */);
         r > 0) {