Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 65d94596 authored by Yifan Hong's avatar Yifan Hong
Browse files

libsnapshot: no overlayfs during virtual a/b ota. 

With overlayfs enabled, the scratch partition takes up
super partition, causing retrofit devices to create COW
images.
Test: OTA on retrofit device, no COW images created.

Change-Id: I35a1a2d02c8acf9efc33965c7e015f960bf45296
parent 20a23bb4

fs_mgr/libsnapshot/include/libsnapshot/snapshot.h

+1 −0
Original line number Diff line number Diff line
@@ -100,6 +100,7 @@ class SnapshotManager final { 
        virtual std::string GetSlotSuffix() const = 0;

        virtual std::string GetSuperDevice(uint32_t slot) const = 0;

        virtual const IPartitionOpener& GetPartitionOpener() const = 0;

        virtual bool IsOverlayfsSetup() const = 0;

    };



    ~SnapshotManager();

fs_mgr/libsnapshot/snapshot.cpp

+11 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#include <ext4_utils/ext4_utils.h>

#include <fs_mgr.h>

#include <fs_mgr_dm_linear.h>

#include <fs_mgr_overlayfs.h>

#include <fstab/fstab.h>

#include <libdm/dm.h>

#include <libfiemap/image_manager.h>
@@ -77,6 +78,7 @@ class DeviceInfo final : public SnapshotManager::IDeviceInfo { 
    std::string GetSuperDevice(uint32_t slot) const override {

        return fs_mgr_get_super_partition_name(slot);

    }

    bool IsOverlayfsSetup() const override { return fs_mgr_overlayfs_is_setup(); }



  private:

    android::fs_mgr::PartitionOpener opener_;
@@ -1731,6 +1733,15 @@ bool SnapshotManager::CreateUpdateSnapshots(MetadataBuilder* target_metadata, 
        return false;

    }



    // TODO(b/134949511): remove this check. Right now, with overlayfs mounted, the scratch

    // partition takes up a big chunk of space in super, causing COW images to be created on

    // retrofit Virtual A/B devices.

    if (device_->IsOverlayfsSetup()) {

        LOG(ERROR) << "Cannot create update snapshots with overlayfs setup. Run `adb enable-verity`"

                   << ", reboot, then try again.";

        return false;

    }



    // Check that all these metadata is not retrofit dynamic partitions. Snapshots on

    // devices with retrofit dynamic partitions does not make sense.

    // This ensures that current_metadata->GetFreeRegions() uses the same device

fs_mgr/libsnapshot/test_helpers.h

+1 −0
Original line number Diff line number Diff line
@@ -51,6 +51,7 @@ class TestDeviceInfo : public SnapshotManager::IDeviceInfo { 
    const android::fs_mgr::IPartitionOpener& GetPartitionOpener() const override {

        return *opener_.get();

    }

    bool IsOverlayfsSetup() const override { return false; }



    void set_slot_suffix(const std::string& suffix) { slot_suffix_ = suffix; }

    void set_fake_super(const std::string& path) {