diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 07eaf58..b1606d9 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -85,6 +85,10 @@
 
 #if ALLOW_ADBD_DISABLE_VERITY == 0  // If we are a user build, provide stubs
 
+bool fs_mgr_wants_overlayfs(FstabEntry*) {
+    return false;
+}
+
 Fstab fs_mgr_overlayfs_candidate_list(const Fstab&) {
     return {};
 }
@@ -388,26 +392,6 @@
     return false;
 }
 
-bool fs_mgr_wants_overlayfs(FstabEntry* entry) {
-    // Don't check entries that are managed by vold.
-    if (entry->fs_mgr_flags.vold_managed || entry->fs_mgr_flags.recovery_only) return false;
-
-    // *_other doesn't want overlayfs.
-    if (entry->fs_mgr_flags.slot_select_other) return false;
-
-    // Only concerned with readonly partitions.
-    if (!(entry->flags & MS_RDONLY)) return false;
-
-    // If unbindable, do not allow overlayfs as this could expose us to
-    // security issues.  On Android, this could also be used to turn off
-    // the ability to overlay an otherwise acceptable filesystem since
-    // /system and /vendor are never bound(sic) to.
-    if (entry->flags & MS_UNBINDABLE) return false;
-
-    if (!fs_mgr_overlayfs_enabled(entry)) return false;
-
-    return true;
-}
 constexpr char kOverlayfsFileContext[] = "u:object_r:overlayfs_file:s0";
 
 bool fs_mgr_overlayfs_setup_dir(const std::string& dir, std::string* overlay, bool* change) {
@@ -1284,6 +1268,27 @@
 
 }  // namespace
 
+bool fs_mgr_wants_overlayfs(FstabEntry* entry) {
+    // Don't check entries that are managed by vold.
+    if (entry->fs_mgr_flags.vold_managed || entry->fs_mgr_flags.recovery_only) return false;
+
+    // *_other doesn't want overlayfs.
+    if (entry->fs_mgr_flags.slot_select_other) return false;
+
+    // Only concerned with readonly partitions.
+    if (!(entry->flags & MS_RDONLY)) return false;
+
+    // If unbindable, do not allow overlayfs as this could expose us to
+    // security issues.  On Android, this could also be used to turn off
+    // the ability to overlay an otherwise acceptable filesystem since
+    // /system and /vendor are never bound(sic) to.
+    if (entry->flags & MS_UNBINDABLE) return false;
+
+    if (!fs_mgr_overlayfs_enabled(entry)) return false;
+
+    return true;
+}
+
 Fstab fs_mgr_overlayfs_candidate_list(const Fstab& fstab) {
     Fstab candidates;
     for (const auto& entry : fstab) {
diff --git a/fs_mgr/fs_mgr_remount.cpp b/fs_mgr/fs_mgr_remount.cpp
index deaf5f7..c47d110 100644
--- a/fs_mgr/fs_mgr_remount.cpp
+++ b/fs_mgr/fs_mgr_remount.cpp
@@ -43,6 +43,8 @@
 #include <libgsi/libgsid.h>
 
 using namespace std::literals;
+using android::fs_mgr::Fstab;
+using android::fs_mgr::FstabEntry;
 
 namespace {
 
@@ -62,22 +64,12 @@
     ::exit(exit_status);
 }
 
-bool remountable_partition(const android::fs_mgr::FstabEntry& entry) {
-    if (entry.fs_mgr_flags.vold_managed) return false;
-    if (entry.fs_mgr_flags.recovery_only) return false;
-    if (entry.fs_mgr_flags.slot_select_other) return false;
-    if (!(entry.flags & MS_RDONLY)) return false;
-    if (entry.fs_type == "vfat") return false;
-    return true;
-}
-
 const std::string system_mount_point(const android::fs_mgr::FstabEntry& entry) {
     if (entry.mount_point == "/") return "/system";
     return entry.mount_point;
 }
 
-const android::fs_mgr::FstabEntry* is_wrapped(const android::fs_mgr::Fstab& overlayfs_candidates,
-                                              const android::fs_mgr::FstabEntry& entry) {
+const FstabEntry* GetWrappedEntry(const Fstab& overlayfs_candidates, const FstabEntry& entry) {
     auto mount_point = system_mount_point(entry);
     auto it = std::find_if(overlayfs_candidates.begin(), overlayfs_candidates.end(),
                            [&mount_point](const auto& entry) {
@@ -147,9 +139,290 @@
     CLEAN_SCRATCH_FILES,
 };
 
-static int do_remount(int argc, char* argv[]) {
-    RemountStatus retval = REMOUNT_SUCCESS;
+static bool ReadFstab(const char* fstab_file, android::fs_mgr::Fstab* fstab) {
+    if (fstab_file) {
+        return android::fs_mgr::ReadFstabFromFile(fstab_file, fstab);
+    }
+    if (!android::fs_mgr::ReadDefaultFstab(fstab)) {
+        return false;
+    }
 
+    // Manufacture a / entry from /proc/mounts if missing.
+    if (!GetEntryForMountPoint(fstab, "/system") && !GetEntryForMountPoint(fstab, "/")) {
+        android::fs_mgr::Fstab mounts;
+        if (android::fs_mgr::ReadFstabFromFile("/proc/mounts", &mounts)) {
+            if (auto entry = GetEntryForMountPoint(&mounts, "/")) {
+                if (entry->fs_type != "rootfs") fstab->emplace_back(*entry);
+            }
+        }
+    }
+    return true;
+}
+
+static RemountStatus VerifyCheckpointing() {
+    if (!android::base::GetBoolProperty("ro.virtual_ab.enabled", false) &&
+        !android::base::GetBoolProperty("ro.virtual_ab.retrofit", false)) {
+        return REMOUNT_SUCCESS;
+    }
+
+    // Virtual A/B devices can use /data as backing storage; make sure we're
+    // not checkpointing.
+    auto vold = GetVold();
+    bool checkpointing = false;
+    if (!vold->isCheckpointing(&checkpointing).isOk()) {
+        LOG(ERROR) << "Could not determine checkpointing status.";
+        return BINDER_ERROR;
+    }
+    if (checkpointing) {
+        LOG(ERROR) << "Cannot use remount when a checkpoint is in progress.";
+        return CHECKPOINTING;
+    }
+    return REMOUNT_SUCCESS;
+}
+
+static bool IsRemountable(Fstab& candidates, const FstabEntry& entry) {
+    if (entry.fs_mgr_flags.vold_managed || entry.fs_mgr_flags.recovery_only ||
+        entry.fs_mgr_flags.slot_select_other) {
+        return false;
+    }
+    if (!(entry.flags & MS_RDONLY)) {
+        return false;
+    }
+    if (entry.fs_type == "vfat") {
+        return false;
+    }
+    if (GetEntryForMountPoint(&candidates, entry.mount_point)) {
+        return true;
+    }
+    if (GetWrappedEntry(candidates, entry)) {
+        return false;
+    }
+    return true;
+}
+
+static Fstab::const_iterator FindPartition(const Fstab& fstab, const std::string& partition) {
+    for (auto iter = fstab.begin(); iter != fstab.end(); iter++) {
+        const auto mount_point = system_mount_point(*iter);
+        if (partition == mount_point) {
+            return iter;
+        }
+        if (partition == android::base::Basename(mount_point)) {
+            return iter;
+        }
+    }
+    return fstab.end();
+}
+
+static Fstab GetAllRemountablePartitions(Fstab& fstab) {
+    auto candidates = fs_mgr_overlayfs_candidate_list(fstab);
+
+    Fstab partitions;
+    for (const auto& entry : fstab) {
+        if (IsRemountable(candidates, entry)) {
+            partitions.emplace_back(entry);
+        }
+    }
+    return partitions;
+}
+
+static RemountStatus GetRemountList(const Fstab& fstab, const std::vector<std::string>& argv,
+                                    Fstab* partitions) {
+    auto candidates = fs_mgr_overlayfs_candidate_list(fstab);
+
+    for (const auto& arg : argv) {
+        std::string partition = arg;
+        if (partition == "/") {
+            partition = "/system";
+        }
+
+        auto it = FindPartition(fstab, partition);
+        if (it == fstab.end()) {
+            LOG(ERROR) << "Unknown partition " << arg;
+            return UNKNOWN_PARTITION;
+        }
+
+        const FstabEntry* entry = &*it;
+        if (auto wrap = GetWrappedEntry(candidates, *entry); wrap != nullptr) {
+            LOG(INFO) << "partition " << arg << " covered by overlayfs for " << wrap->mount_point
+                      << ", switching";
+            entry = wrap;
+        }
+
+        if (!IsRemountable(candidates, *entry)) {
+            LOG(ERROR) << "Invalid partition " << arg;
+            return INVALID_PARTITION;
+        }
+        if (GetEntryForMountPoint(partitions, entry->mount_point) != nullptr) {
+            continue;
+        }
+        partitions->emplace_back(*entry);
+    }
+
+    return REMOUNT_SUCCESS;
+}
+
+struct RemountCheckResult {
+    bool reboot_later = false;
+    bool setup_overlayfs = false;
+    bool disabled_verity = false;
+    bool verity_error = false;
+};
+
+static RemountStatus CheckVerity(const FstabEntry& entry, RemountCheckResult* result) {
+    if (!fs_mgr_is_verity_enabled(entry)) {
+        return REMOUNT_SUCCESS;
+    }
+    if (android::base::GetProperty("ro.boot.vbmeta.device_state", "") == "locked") {
+        return VERITY_PARTITION;
+    }
+
+    bool ok = false;
+
+    std::unique_ptr<AvbOps, decltype(&::avb_ops_user_free)> ops(avb_ops_user_new(),
+                                                                &::avb_ops_user_free);
+    if (ops) {
+        auto suffix = android::base::GetProperty("ro.boot.slot_suffix", "");
+        ok = avb_user_verity_set(ops.get(), suffix.c_str(), false);
+    }
+    if (!ok && fs_mgr_set_blk_ro(entry.blk_device, false)) {
+        fec::io fh(entry.blk_device.c_str(), O_RDWR);
+        ok = fh && fh.set_verity_status(false);
+    }
+    if (!ok) {
+        return VERITY_PARTITION;
+    }
+    result->disabled_verity = true;
+    result->reboot_later = true;
+    return REMOUNT_SUCCESS;
+}
+
+static RemountStatus CheckVerityAndOverlayfs(Fstab* partitions, RemountCheckResult* result) {
+    RemountStatus status = REMOUNT_SUCCESS;
+    for (auto it = partitions->begin(); it != partitions->end();) {
+        auto& entry = *it;
+        const auto& mount_point = entry.mount_point;
+
+        if (auto rv = CheckVerity(entry, result); rv != REMOUNT_SUCCESS) {
+            LOG(ERROR) << "Skipping verified partition " << mount_point << " for remount";
+            status = rv;
+            it = partitions->erase(it);
+            continue;
+        }
+
+        if (fs_mgr_wants_overlayfs(&entry)) {
+            bool change = false;
+            bool force = result->disabled_verity;
+            if (!fs_mgr_overlayfs_setup(nullptr, mount_point.c_str(), &change, force)) {
+                LOG(ERROR) << "Overlayfs setup for " << mount_point << " failed, skipping";
+                status = BAD_OVERLAY;
+                it = partitions->erase(it);
+                continue;
+            }
+            if (change) {
+                LOG(INFO) << "Using overlayfs for " << mount_point;
+                result->reboot_later = true;
+                result->setup_overlayfs = true;
+            }
+        }
+        it++;
+    }
+    return status;
+}
+
+static RemountStatus EnableDsuIfNeeded() {
+    auto gsid = android::gsi::GetGsiService();
+    if (!gsid) {
+        return REMOUNT_SUCCESS;
+    }
+
+    auto dsu_running = false;
+    if (auto status = gsid->isGsiRunning(&dsu_running); !status.isOk()) {
+        LOG(ERROR) << "Failed to get DSU running state: " << status;
+        return BINDER_ERROR;
+    }
+    auto dsu_enabled = false;
+    if (auto status = gsid->isGsiEnabled(&dsu_enabled); !status.isOk()) {
+        LOG(ERROR) << "Failed to get DSU enabled state: " << status;
+        return BINDER_ERROR;
+    }
+    if (dsu_running && !dsu_enabled) {
+        std::string dsu_slot;
+        if (auto status = gsid->getActiveDsuSlot(&dsu_slot); !status.isOk()) {
+            LOG(ERROR) << "Failed to get active DSU slot: " << status;
+            return BINDER_ERROR;
+        }
+        LOG(INFO) << "DSU is running but disabled, enable DSU so that we stay within the "
+                     "DSU guest system after reboot";
+        int error = 0;
+        if (auto status = gsid->enableGsi(/* oneShot = */ true, dsu_slot, &error);
+            !status.isOk() || error != android::gsi::IGsiService::INSTALL_OK) {
+            LOG(ERROR) << "Failed to enable DSU: " << status << ", error code: " << error;
+            return !status.isOk() ? BINDER_ERROR : GSID_ERROR;
+        }
+        LOG(INFO) << "Successfully enabled DSU (one-shot mode)";
+    }
+    return REMOUNT_SUCCESS;
+}
+
+static RemountStatus RemountPartition(Fstab& fstab, Fstab& mounts, FstabEntry& entry) {
+    // unlock the r/o key for the mount point device
+    if (entry.fs_mgr_flags.logical) {
+        fs_mgr_update_logical_partition(&entry);
+    }
+    auto blk_device = entry.blk_device;
+    auto mount_point = entry.mount_point;
+
+    auto found = false;
+    for (auto it = mounts.rbegin(); it != mounts.rend(); ++it) {
+        auto& rentry = *it;
+        if (mount_point == rentry.mount_point) {
+            blk_device = rentry.blk_device;
+            found = true;
+            break;
+        }
+        // Find overlayfs mount point?
+        if ((mount_point == "/" && rentry.mount_point == "/system") ||
+            (mount_point == "/system" && rentry.mount_point == "/")) {
+            blk_device = rentry.blk_device;
+            mount_point = "/system";
+            found = true;
+            break;
+        }
+    }
+    if (!found) {
+        PLOG(INFO) << "skip unmounted partition dev:" << blk_device << " mnt:" << mount_point;
+        return REMOUNT_SUCCESS;
+    }
+    if (blk_device == "/dev/root") {
+        auto from_fstab = GetEntryForMountPoint(&fstab, mount_point);
+        if (from_fstab) blk_device = from_fstab->blk_device;
+    }
+    fs_mgr_set_blk_ro(blk_device, false);
+
+    // Find system-as-root mount point?
+    if ((mount_point == "/system") && !GetEntryForMountPoint(&mounts, mount_point) &&
+        GetEntryForMountPoint(&mounts, "/")) {
+        mount_point = "/";
+    }
+
+    // Now remount!
+    if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
+                nullptr) == 0) {
+        return REMOUNT_SUCCESS;
+    }
+    if ((errno == EINVAL) && (mount_point != entry.mount_point)) {
+        mount_point = entry.mount_point;
+        if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
+                    nullptr) == 0) {
+            return REMOUNT_SUCCESS;
+        }
+    }
+
+    PLOG(ERROR) << "failed to remount partition dev:" << blk_device << " mnt:" << mount_point;
+    return REMOUNT_FAILED;
+}
+
+static int do_remount(int argc, char* argv[]) {
     // If somehow this executable is delivered on a "user" build, it can
     // not function, so providing a clear message to the caller rather than
     // letting if fall through and provide a lot of confusing failure messages.
@@ -160,6 +433,7 @@
 
     const char* fstab_file = nullptr;
     auto can_reboot = false;
+    std::vector<std::string> partition_args;
 
     struct option longopts[] = {
             {"fstab", required_argument, nullptr, 'T'},
@@ -196,6 +470,10 @@
         }
     }
 
+    for (; argc > optind; ++optind) {
+        partition_args.emplace_back(argv[optind]);
+    }
+
     // Make sure we are root.
     if (::getuid() != 0) {
         LOG(ERROR) << "Not running as root. Try \"adb root\" first.";
@@ -203,191 +481,46 @@
     }
 
     // Read the selected fstab.
-    android::fs_mgr::Fstab fstab;
-    auto fstab_read = false;
-    if (fstab_file) {
-        fstab_read = android::fs_mgr::ReadFstabFromFile(fstab_file, &fstab);
-    } else {
-        fstab_read = android::fs_mgr::ReadDefaultFstab(&fstab);
-        // Manufacture a / entry from /proc/mounts if missing.
-        if (!GetEntryForMountPoint(&fstab, "/system") && !GetEntryForMountPoint(&fstab, "/")) {
-            android::fs_mgr::Fstab mounts;
-            if (android::fs_mgr::ReadFstabFromFile("/proc/mounts", &mounts)) {
-                if (auto entry = GetEntryForMountPoint(&mounts, "/")) {
-                    if (entry->fs_type != "rootfs") fstab.emplace_back(*entry);
-                }
-            }
-        }
-    }
-    if (!fstab_read || fstab.empty()) {
+    Fstab fstab;
+    if (!ReadFstab(fstab_file, &fstab) || fstab.empty()) {
         PLOG(ERROR) << "Failed to read fstab";
         return NO_FSTAB;
     }
 
-    if (android::base::GetBoolProperty("ro.virtual_ab.enabled", false) &&
-        !android::base::GetBoolProperty("ro.virtual_ab.retrofit", false)) {
-        // Virtual A/B devices can use /data as backing storage; make sure we're
-        // not checkpointing.
-        auto vold = GetVold();
-        bool checkpointing = false;
-        if (!vold->isCheckpointing(&checkpointing).isOk()) {
-            LOG(ERROR) << "Could not determine checkpointing status.";
-            return BINDER_ERROR;
-        }
-        if (checkpointing) {
-            LOG(ERROR) << "Cannot use remount when a checkpoint is in progress.";
-            return CHECKPOINTING;
-        }
+    if (auto rv = VerifyCheckpointing(); rv != REMOUNT_SUCCESS) {
+        return rv;
     }
 
-    // Generate the list of supported overlayfs mount points.
-    auto overlayfs_candidates = fs_mgr_overlayfs_candidate_list(fstab);
-
-    // Generate the all remountable partitions sub-list
-    android::fs_mgr::Fstab all;
-    for (auto const& entry : fstab) {
-        if (!remountable_partition(entry)) continue;
-        if (overlayfs_candidates.empty() ||
-            GetEntryForMountPoint(&overlayfs_candidates, entry.mount_point) ||
-            (is_wrapped(overlayfs_candidates, entry) == nullptr)) {
-            all.emplace_back(entry);
+    Fstab partitions;
+    if (partition_args.empty()) {
+        partitions = GetAllRemountablePartitions(fstab);
+    } else {
+        if (auto rv = GetRemountList(fstab, partition_args, &partitions); rv != REMOUNT_SUCCESS) {
+            return rv;
         }
     }
 
-    // Parse the unique list of valid partition arguments.
-    android::fs_mgr::Fstab partitions;
-    for (; argc > optind; ++optind) {
-        auto partition = std::string(argv[optind]);
-        if (partition.empty()) continue;
-        if (partition == "/") partition = "/system";
-        auto find_part = [&partition](const auto& entry) {
-            const auto mount_point = system_mount_point(entry);
-            if (partition == mount_point) return true;
-            if (partition == android::base::Basename(mount_point)) return true;
-            return false;
-        };
-        // Do we know about the partition?
-        auto it = std::find_if(fstab.begin(), fstab.end(), find_part);
-        if (it == fstab.end()) {
-            LOG(ERROR) << "Unknown partition " << argv[optind] << ", skipping";
-            retval = UNKNOWN_PARTITION;
-            continue;
-        }
-        // Is that one covered by an existing overlayfs?
-        auto wrap = is_wrapped(overlayfs_candidates, *it);
-        if (wrap) {
-            LOG(INFO) << "partition " << argv[optind] << " covered by overlayfs for "
-                      << wrap->mount_point << ", switching";
-            partition = system_mount_point(*wrap);
-        }
-        // Is it a remountable partition?
-        it = std::find_if(all.begin(), all.end(), find_part);
-        if (it == all.end()) {
-            LOG(ERROR) << "Invalid partition " << argv[optind] << ", skipping";
-            retval = INVALID_PARTITION;
-            continue;
-        }
-        if (GetEntryForMountPoint(&partitions, it->mount_point) == nullptr) {
-            partitions.emplace_back(*it);
-        }
-    }
-
-    if (partitions.empty() && !retval) {
-        partitions = all;
-    }
-
     // Check verity and optionally setup overlayfs backing.
-    auto reboot_later = false;
-    auto user_please_reboot_later = false;
-    auto setup_overlayfs = false;
-    auto just_disabled_verity = false;
-    for (auto it = partitions.begin(); it != partitions.end();) {
-        auto& entry = *it;
-        auto& mount_point = entry.mount_point;
-        if (fs_mgr_is_verity_enabled(entry)) {
-            retval = VERITY_PARTITION;
-            auto ret = false;
-            if (android::base::GetProperty("ro.boot.vbmeta.device_state", "") != "locked") {
-                if (AvbOps* ops = avb_ops_user_new()) {
-                    ret = avb_user_verity_set(
-                            ops, android::base::GetProperty("ro.boot.slot_suffix", "").c_str(),
-                            false);
-                    avb_ops_user_free(ops);
-                }
-                if (!ret && fs_mgr_set_blk_ro(entry.blk_device, false)) {
-                    fec::io fh(entry.blk_device.c_str(), O_RDWR);
-                    ret = fh && fh.set_verity_status(false);
-                }
-                if (ret) {
-                    LOG(WARNING) << "Disabling verity for " << mount_point;
-                    just_disabled_verity = true;
-                    reboot_later = can_reboot;
-                    user_please_reboot_later = true;
-                }
-            }
-            if (!ret) {
-                LOG(ERROR) << "Skipping " << mount_point << " for remount";
-                it = partitions.erase(it);
-                continue;
-            }
-        }
+    RemountCheckResult check_result;
+    auto retval = CheckVerityAndOverlayfs(&partitions, &check_result);
 
-        auto change = false;
-        errno = 0;
-        if (fs_mgr_overlayfs_setup(nullptr, mount_point.c_str(), &change, just_disabled_verity)) {
-            if (change) {
-                LOG(INFO) << "Using overlayfs for " << mount_point;
-                reboot_later = can_reboot;
-                user_please_reboot_later = true;
-                setup_overlayfs = true;
-            }
-        } else if (errno) {
-            PLOG(ERROR) << "Overlayfs setup for " << mount_point << " failed, skipping";
-            retval = BAD_OVERLAY;
-            it = partitions.erase(it);
-            continue;
-        }
-        ++it;
-    }
+    bool auto_reboot = check_result.reboot_later && can_reboot;
 
     // If (1) remount requires a reboot to take effect, (2) system is currently
     // running a DSU guest and (3) DSU is disabled, then enable DSU so that the
     // next reboot would not take us back to the host system but stay within
     // the guest system.
-    if (reboot_later) {
-        if (auto gsid = android::gsi::GetGsiService()) {
-            auto dsu_running = false;
-            if (auto status = gsid->isGsiRunning(&dsu_running); !status.isOk()) {
-                LOG(ERROR) << "Failed to get DSU running state: " << status;
-                return BINDER_ERROR;
-            }
-            auto dsu_enabled = false;
-            if (auto status = gsid->isGsiEnabled(&dsu_enabled); !status.isOk()) {
-                LOG(ERROR) << "Failed to get DSU enabled state: " << status;
-                return BINDER_ERROR;
-            }
-            if (dsu_running && !dsu_enabled) {
-                std::string dsu_slot;
-                if (auto status = gsid->getActiveDsuSlot(&dsu_slot); !status.isOk()) {
-                    LOG(ERROR) << "Failed to get active DSU slot: " << status;
-                    return BINDER_ERROR;
-                }
-                LOG(INFO) << "DSU is running but disabled, enable DSU so that we stay within the "
-                             "DSU guest system after reboot";
-                int error = 0;
-                if (auto status = gsid->enableGsi(/* oneShot = */ true, dsu_slot, &error);
-                    !status.isOk() || error != android::gsi::IGsiService::INSTALL_OK) {
-                    LOG(ERROR) << "Failed to enable DSU: " << status << ", error code: " << error;
-                    return !status.isOk() ? BINDER_ERROR : GSID_ERROR;
-                }
-                LOG(INFO) << "Successfully enabled DSU (one-shot mode)";
-            }
+    if (auto_reboot) {
+        if (auto rv = EnableDsuIfNeeded(); rv != REMOUNT_SUCCESS) {
+            return rv;
         }
     }
 
-    if (partitions.empty() || just_disabled_verity) {
-        if (reboot_later) reboot(setup_overlayfs);
-        if (user_please_reboot_later) {
+    if (partitions.empty() || check_result.disabled_verity) {
+        if (auto_reboot) {
+            reboot(check_result.setup_overlayfs);
+        }
+        if (check_result.reboot_later) {
             return MUST_REBOOT;
         }
         LOG(WARNING) << "No partitions to remount";
@@ -397,88 +530,28 @@
     // Mount overlayfs.
     errno = 0;
     if (!fs_mgr_overlayfs_mount_all(&partitions) && errno) {
-        retval = BAD_OVERLAY;
         PLOG(ERROR) << "Can not mount overlayfs for partitions";
+        return BAD_OVERLAY;
     }
 
     // Get actual mounts _after_ overlayfs has been added.
     android::fs_mgr::Fstab mounts;
     if (!android::fs_mgr::ReadFstabFromFile("/proc/mounts", &mounts) || mounts.empty()) {
         PLOG(ERROR) << "Failed to read /proc/mounts";
-        retval = NO_MOUNTS;
+        return NO_MOUNTS;
     }
 
     // Remount selected partitions.
     for (auto& entry : partitions) {
-        // unlock the r/o key for the mount point device
-        if (entry.fs_mgr_flags.logical) {
-            fs_mgr_update_logical_partition(&entry);
+        if (auto rv = RemountPartition(fstab, mounts, entry); rv != REMOUNT_SUCCESS) {
+            retval = rv;
         }
-        auto blk_device = entry.blk_device;
-        auto mount_point = entry.mount_point;
-
-        auto found = false;
-        for (auto it = mounts.rbegin(); it != mounts.rend(); ++it) {
-            auto& rentry = *it;
-            if (mount_point == rentry.mount_point) {
-                blk_device = rentry.blk_device;
-                found = true;
-                break;
-            }
-            // Find overlayfs mount point?
-            if ((mount_point == "/" && rentry.mount_point == "/system")  ||
-                (mount_point == "/system" && rentry.mount_point == "/")) {
-                blk_device = rentry.blk_device;
-                mount_point = "/system";
-                found = true;
-                break;
-            }
-        }
-        if (!found) {
-            PLOG(INFO) << "skip unmounted partition dev:" << blk_device << " mnt:" << mount_point;
-            continue;
-        }
-        if (blk_device == "/dev/root") {
-            auto from_fstab = GetEntryForMountPoint(&fstab, mount_point);
-            if (from_fstab) blk_device = from_fstab->blk_device;
-        }
-        fs_mgr_set_blk_ro(blk_device, false);
-
-        // Find system-as-root mount point?
-        if ((mount_point == "/system") && !GetEntryForMountPoint(&mounts, mount_point) &&
-            GetEntryForMountPoint(&mounts, "/")) {
-            mount_point = "/";
-        }
-
-        // Now remount!
-        if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
-                    nullptr) == 0) {
-            continue;
-        }
-        if ((errno == EINVAL) && (mount_point != entry.mount_point)) {
-            mount_point = entry.mount_point;
-            if (::mount(blk_device.c_str(), mount_point.c_str(), entry.fs_type.c_str(), MS_REMOUNT,
-                        nullptr) == 0) {
-                continue;
-            }
-        }
-        PLOG(ERROR) << "failed to remount partition dev:" << blk_device << " mnt:" << mount_point;
-        // If errno is EROFS at this point, we are dealing with r/o
-        // filesystem types like squashfs, erofs or ext4 dedupe. We will
-        // consider such a device that does not have CONFIG_OVERLAY_FS
-        // in the kernel as a misconfigured.
-        if (errno == EROFS) {
-            LOG(ERROR) << "Consider providing all the dependencies to enable overlayfs";
-        }
-        retval = REMOUNT_FAILED;
     }
 
-    if (reboot_later) reboot(setup_overlayfs);
-    if (user_please_reboot_later) {
+    if (auto_reboot) reboot(check_result.setup_overlayfs);
+    if (check_result.reboot_later) {
         LOG(INFO) << "Now reboot your device for settings to take effect";
-        return 0;
     }
-
     return retval;
 }
 
diff --git a/fs_mgr/include/fs_mgr_overlayfs.h b/fs_mgr/include/fs_mgr_overlayfs.h
index 6caab1f..21d7cd9 100644
--- a/fs_mgr/include/fs_mgr_overlayfs.h
+++ b/fs_mgr/include/fs_mgr_overlayfs.h
@@ -26,6 +26,7 @@
 
 android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);
 
+bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);
 bool fs_mgr_overlayfs_mount_all(android::fs_mgr::Fstab* fstab);
 bool fs_mgr_overlayfs_setup(const char* backing = nullptr, const char* mount_point = nullptr,
                             bool* change = nullptr, bool force = true);
diff --git a/fs_mgr/libsnapshot/cow_reader.cpp b/fs_mgr/libsnapshot/cow_reader.cpp
index 653492c..c8a0249 100644
--- a/fs_mgr/libsnapshot/cow_reader.cpp
+++ b/fs_mgr/libsnapshot/cow_reader.cpp
@@ -38,7 +38,7 @@
     : fd_(-1),
       header_(),
       fd_size_(0),
-      merge_op_blocks_(std::make_shared<std::vector<uint32_t>>()),
+      block_pos_index_(std::make_shared<std::vector<int>>()),
       reader_flag_(reader_flag) {}
 
 static void SHA256(const void*, size_t, uint8_t[]) {
@@ -58,13 +58,12 @@
     cow->fd_size_ = fd_size_;
     cow->last_label_ = last_label_;
     cow->ops_ = ops_;
-    cow->merge_op_blocks_ = merge_op_blocks_;
     cow->merge_op_start_ = merge_op_start_;
-    cow->block_map_ = block_map_;
     cow->num_total_data_ops_ = num_total_data_ops_;
     cow->num_ordered_ops_to_merge_ = num_ordered_ops_to_merge_;
     cow->has_seq_ops_ = has_seq_ops_;
     cow->data_loc_ = data_loc_;
+    cow->block_pos_index_ = block_pos_index_;
     return cow;
 }
 
@@ -415,10 +414,10 @@
 //                        Replace-op-4, Zero-op-9, Replace-op-5 }
 //==============================================================
 bool CowReader::PrepMergeOps() {
-    auto merge_op_blocks = std::make_shared<std::vector<uint32_t>>();
+    auto merge_op_blocks = std::make_unique<std::vector<uint32_t>>();
     std::vector<int> other_ops;
     auto seq_ops_set = std::unordered_set<uint32_t>();
-    auto block_map = std::make_shared<std::unordered_map<uint32_t, int>>();
+    auto block_map = std::make_unique<std::unordered_map<uint32_t, int>>();
     size_t num_seqs = 0;
     size_t read;
 
@@ -477,13 +476,18 @@
 
     merge_op_blocks->insert(merge_op_blocks->end(), other_ops.begin(), other_ops.end());
 
+    for (auto block : *merge_op_blocks) {
+        block_pos_index_->push_back(block_map->at(block));
+    }
+
     num_total_data_ops_ = merge_op_blocks->size();
     if (header_.num_merge_ops > 0) {
         merge_op_start_ = header_.num_merge_ops;
     }
 
-    block_map_ = block_map;
-    merge_op_blocks_ = merge_op_blocks;
+    block_map->clear();
+    merge_op_blocks->clear();
+
     return true;
 }
 
@@ -589,9 +593,7 @@
 class CowRevMergeOpIter final : public ICowOpIter {
   public:
     explicit CowRevMergeOpIter(std::shared_ptr<std::vector<CowOperation>> ops,
-                               std::shared_ptr<std::vector<uint32_t>> merge_op_blocks,
-                               std::shared_ptr<std::unordered_map<uint32_t, int>> map,
-                               uint64_t start);
+                               std::shared_ptr<std::vector<int>> block_pos_index, uint64_t start);
 
     bool Done() override;
     const CowOperation& Get() override;
@@ -602,17 +604,15 @@
 
   private:
     std::shared_ptr<std::vector<CowOperation>> ops_;
-    std::shared_ptr<std::vector<uint32_t>> merge_op_blocks_;
-    std::shared_ptr<std::unordered_map<uint32_t, int>> map_;
-    std::vector<uint32_t>::reverse_iterator block_riter_;
+    std::vector<int>::reverse_iterator block_riter_;
+    std::shared_ptr<std::vector<int>> cow_op_index_vec_;
     uint64_t start_;
 };
 
 class CowMergeOpIter final : public ICowOpIter {
   public:
     explicit CowMergeOpIter(std::shared_ptr<std::vector<CowOperation>> ops,
-                            std::shared_ptr<std::vector<uint32_t>> merge_op_blocks,
-                            std::shared_ptr<std::unordered_map<uint32_t, int>> map, uint64_t start);
+                            std::shared_ptr<std::vector<int>> block_pos_index, uint64_t start);
 
     bool Done() override;
     const CowOperation& Get() override;
@@ -623,26 +623,21 @@
 
   private:
     std::shared_ptr<std::vector<CowOperation>> ops_;
-    std::shared_ptr<std::vector<uint32_t>> merge_op_blocks_;
-    std::shared_ptr<std::unordered_map<uint32_t, int>> map_;
-    std::vector<uint32_t>::iterator block_iter_;
+    std::vector<int>::iterator block_iter_;
+    std::shared_ptr<std::vector<int>> cow_op_index_vec_;
     uint64_t start_;
 };
 
 CowMergeOpIter::CowMergeOpIter(std::shared_ptr<std::vector<CowOperation>> ops,
-                               std::shared_ptr<std::vector<uint32_t>> merge_op_blocks,
-                               std::shared_ptr<std::unordered_map<uint32_t, int>> map,
-                               uint64_t start) {
+                               std::shared_ptr<std::vector<int>> block_pos_index, uint64_t start) {
     ops_ = ops;
-    merge_op_blocks_ = merge_op_blocks;
-    map_ = map;
     start_ = start;
-
-    block_iter_ = merge_op_blocks->begin() + start;
+    cow_op_index_vec_ = block_pos_index;
+    block_iter_ = cow_op_index_vec_->begin() + start;
 }
 
 bool CowMergeOpIter::RDone() {
-    return block_iter_ == merge_op_blocks_->begin();
+    return block_iter_ == cow_op_index_vec_->begin();
 }
 
 void CowMergeOpIter::Prev() {
@@ -651,7 +646,7 @@
 }
 
 bool CowMergeOpIter::Done() {
-    return block_iter_ == merge_op_blocks_->end();
+    return block_iter_ == cow_op_index_vec_->end();
 }
 
 void CowMergeOpIter::Next() {
@@ -661,23 +656,20 @@
 
 const CowOperation& CowMergeOpIter::Get() {
     CHECK(!Done());
-    return ops_->data()[map_->at(*block_iter_)];
+    return ops_->data()[*block_iter_];
 }
 
 CowRevMergeOpIter::CowRevMergeOpIter(std::shared_ptr<std::vector<CowOperation>> ops,
-                                     std::shared_ptr<std::vector<uint32_t>> merge_op_blocks,
-                                     std::shared_ptr<std::unordered_map<uint32_t, int>> map,
+                                     std::shared_ptr<std::vector<int>> block_pos_index,
                                      uint64_t start) {
     ops_ = ops;
-    merge_op_blocks_ = merge_op_blocks;
-    map_ = map;
     start_ = start;
-
-    block_riter_ = merge_op_blocks->rbegin();
+    cow_op_index_vec_ = block_pos_index;
+    block_riter_ = cow_op_index_vec_->rbegin();
 }
 
 bool CowRevMergeOpIter::RDone() {
-    return block_riter_ == merge_op_blocks_->rbegin();
+    return block_riter_ == cow_op_index_vec_->rbegin();
 }
 
 void CowRevMergeOpIter::Prev() {
@@ -686,7 +678,7 @@
 }
 
 bool CowRevMergeOpIter::Done() {
-    return block_riter_ == merge_op_blocks_->rend() - start_;
+    return block_riter_ == cow_op_index_vec_->rend() - start_;
 }
 
 void CowRevMergeOpIter::Next() {
@@ -696,7 +688,7 @@
 
 const CowOperation& CowRevMergeOpIter::Get() {
     CHECK(!Done());
-    return ops_->data()[map_->at(*block_riter_)];
+    return ops_->data()[*block_riter_];
 }
 
 std::unique_ptr<ICowOpIter> CowReader::GetOpIter() {
@@ -704,12 +696,12 @@
 }
 
 std::unique_ptr<ICowOpIter> CowReader::GetRevMergeOpIter(bool ignore_progress) {
-    return std::make_unique<CowRevMergeOpIter>(ops_, merge_op_blocks_, block_map_,
+    return std::make_unique<CowRevMergeOpIter>(ops_, block_pos_index_,
                                                ignore_progress ? 0 : merge_op_start_);
 }
 
 std::unique_ptr<ICowOpIter> CowReader::GetMergeOpIter(bool ignore_progress) {
-    return std::make_unique<CowMergeOpIter>(ops_, merge_op_blocks_, block_map_,
+    return std::make_unique<CowMergeOpIter>(ops_, block_pos_index_,
                                             ignore_progress ? 0 : merge_op_start_);
 }
 
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
index f4d5c72..fbdd6b9 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
@@ -170,9 +170,8 @@
     uint64_t fd_size_;
     std::optional<uint64_t> last_label_;
     std::shared_ptr<std::vector<CowOperation>> ops_;
-    std::shared_ptr<std::vector<uint32_t>> merge_op_blocks_;
     uint64_t merge_op_start_{};
-    std::shared_ptr<std::unordered_map<uint32_t, int>> block_map_;
+    std::shared_ptr<std::vector<int>> block_pos_index_;
     uint64_t num_total_data_ops_{};
     uint64_t num_ordered_ops_to_merge_{};
     bool has_seq_ops_{};
diff --git a/libstats/pull_rust/Android.bp b/libstats/pull_rust/Android.bp
index 4ffa98d..a3ef131 100644
--- a/libstats/pull_rust/Android.bp
+++ b/libstats/pull_rust/Android.bp
@@ -22,6 +22,10 @@
     name: "libstatspull_bindgen",
     wrapper_src: "statslog.h",
     crate_name: "statspull_bindgen",
+    visibility: [
+        "//frameworks/proto_logging/stats/stats_log_api_gen",
+        "//packages/modules/Virtualization/libs/statslog_virtualization",
+    ],
     source_stem: "bindings",
     bindgen_flags: [
         "--size_t-is-usize",
@@ -48,7 +52,7 @@
     apex_available: [
         "//apex_available:platform",
         "com.android.virt",
-    ]
+    ],
 }
 
 rust_library {
diff --git a/set-verity-state/OWNERS b/set-verity-state/OWNERS
new file mode 100644
index 0000000..e849450
--- /dev/null
+++ b/set-verity-state/OWNERS
@@ -0,0 +1,3 @@
+dvander@google.com
+yochiang@google.com
+bowgotsai@google.com
diff --git a/trusty/OWNERS b/trusty/OWNERS
index 5c4e03a..61b97c6 100644
--- a/trusty/OWNERS
+++ b/trusty/OWNERS
@@ -1,9 +1,11 @@
 armellel@google.com
 arve@android.com
+danielangell@google.com
 gmar@google.com
 marcone@google.com
 mmaurer@google.com
 ncbray@google.com
 swillden@google.com
+thurston@google.com
 trong@google.com
 wenhaowang@google.com
diff --git a/trusty/storage/interface/include/trusty/interface/storage.h b/trusty/storage/interface/include/trusty/interface/storage.h
index 3f1dcb8..255ade1 100644
--- a/trusty/storage/interface/include/trusty/interface/storage.h
+++ b/trusty/storage/interface/include/trusty/interface/storage.h
@@ -70,6 +70,9 @@
  * @STORAGE_ERR_TRANSACT        returned by various operations to indicate that current transaction
  *                              is in error state. Such state could be only cleared by sending
  *                              STORAGE_END_TRANSACTION message.
+ * @STORAGE_ERR_SYNC_FAILURE    indicates that the current operation failed to sync
+ *                              to disk. Only returned if STORAGE_MSG_FLAG_PRE_COMMIT or
+ *                              STORAGE_MSG_FLAG_POST_COMMIT was set for the request.
  */
 enum storage_err {
 	STORAGE_NO_ERROR          = 0,
@@ -80,6 +83,7 @@
 	STORAGE_ERR_NOT_FOUND     = 5,
 	STORAGE_ERR_EXIST         = 6,
 	STORAGE_ERR_TRANSACT      = 7,
+	STORAGE_ERR_SYNC_FAILURE  = 8,
 };
 
 /**
diff --git a/trusty/storage/proxy/proxy.c b/trusty/storage/proxy/proxy.c
index 7cbc24f..b970406 100644
--- a/trusty/storage/proxy/proxy.c
+++ b/trusty/storage/proxy/proxy.c
@@ -73,10 +73,11 @@
 static int handle_req(struct storage_msg* msg, const void* req, size_t req_len) {
     int rc;
 
-    if ((msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) && (msg->cmd != STORAGE_RPMB_SEND)) {
+    if ((msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) && msg->cmd != STORAGE_RPMB_SEND &&
+        msg->cmd != STORAGE_FILE_WRITE) {
         /*
-         * handling post commit messages on non rpmb commands are not
-         * implemented as there is no use case for this yet.
+         * handling post commit messages on commands other than rpmb and write
+         * operations are not implemented as there is no use case for this yet.
          */
         ALOGE("cmd 0x%x: post commit option is not implemented\n", msg->cmd);
         msg->result = STORAGE_ERR_UNIMPLEMENTED;
@@ -86,7 +87,7 @@
     if (msg->flags & STORAGE_MSG_FLAG_PRE_COMMIT) {
         rc = storage_sync_checkpoint();
         if (rc < 0) {
-            msg->result = STORAGE_ERR_GENERIC;
+            msg->result = STORAGE_ERR_SYNC_FAILURE;
             return ipc_respond(msg, NULL, 0);
         }
     }
diff --git a/trusty/storage/proxy/storage.c b/trusty/storage/proxy/storage.c
index c00c399..c531cfd 100644
--- a/trusty/storage/proxy/storage.c
+++ b/trusty/storage/proxy/storage.c
@@ -407,6 +407,14 @@
         goto err_response;
     }
 
+    if (msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) {
+        rc = storage_sync_checkpoint();
+        if (rc < 0) {
+            msg->result = STORAGE_ERR_SYNC_FAILURE;
+            goto err_response;
+        }
+    }
+
     msg->result = STORAGE_NO_ERROR;
 
 err_response: