Track image sizes separately from image files.
If FiemapWriter needs to bump up the image file size due to alignment,
gsid must track the actual requested size separately for AVB to work.
Otherwise, libavb will be unable to find the vbmeta footer at the end of
the partition.
The actual size can be recovered from /metadata/gsi/lp_metadata, as long
as the extent list is truncated appropriately.
Bug: 126230649
Test: gsi install works
Change-Id: If5b580691d9399dfefceef89cc7e574d422f06e2
diff --git a/gsi_service.cpp b/gsi_service.cpp
index cafa379..5b975ac 100644
--- a/gsi_service.cpp
+++ b/gsi_service.cpp
@@ -320,6 +320,16 @@
can_use_devicemapper_ = false;
gsi_bytes_written_ = 0;
+ if (gsi_size % LP_SECTOR_SIZE) {
+ LOG(ERROR) << "GSI size " << gsi_size << " is not a multiple of " << LP_SECTOR_SIZE;
+ return INSTALL_ERROR_GENERIC;
+ }
+ if (userdata_size % LP_SECTOR_SIZE) {
+ LOG(ERROR) << "userdata size " << userdata_size << " is not a multiple of "
+ << LP_SECTOR_SIZE;
+ return INSTALL_ERROR_GENERIC;
+ }
+
if (int status = PerformSanityChecks()) {
return status;
}
@@ -446,7 +456,11 @@
userdata_block_size_ = userdata_image->block_size();
- partitions->emplace(std::make_pair("userdata_gsi", std::move(userdata_image)));
+ Image image = {
+ .writer = std::move(userdata_image),
+ .actual_size = userdata_size_,
+ };
+ partitions->emplace(std::make_pair("userdata_gsi", std::move(image)));
return INSTALL_OK;
}
@@ -461,7 +475,11 @@
system_block_size_ = system_image->block_size();
- partitions->emplace(std::make_pair("system_gsi", std::move(system_image)));
+ Image image = {
+ .writer = std::move(system_image),
+ .actual_size = gsi_size_,
+ };
+ partitions->emplace(std::make_pair("system_gsi", std::move(image)));
return INSTALL_OK;
}
@@ -629,24 +647,27 @@
return INSTALL_ERROR_GENERIC;
}
+ auto metadata = ReadFromImageFile(kGsiLpMetadataFile);
+ if (!metadata) {
+ LOG(ERROR) << "GSI install is incomplete";
+ return INSTALL_ERROR_GENERIC;
+ }
+
ImageMap partitions;
- int error;
- auto userdata_image = CreateFiemapWriter(kUserdataFile, 0, &error);
- if (!userdata_image) {
- LOG(ERROR) << "could not find userdata image";
+ Image userdata_image;
+ if (int error = GetExistingImage(*metadata.get(), "userdata_gsi", &userdata_image)) {
return error;
}
partitions.emplace(std::make_pair("userdata_gsi", std::move(userdata_image)));
- auto system_image = CreateFiemapWriter(kSystemFile, 0, &error);
- if (!system_image) {
- LOG(ERROR) << "could not find system image";
+ Image system_image;
+ if (int error = GetExistingImage(*metadata.get(), "system_gsi", &system_image)) {
return error;
}
partitions.emplace(std::make_pair("system_gsi", std::move(system_image)));
- auto metadata = CreateMetadata(partitions);
+ metadata = CreateMetadata(partitions);
if (!metadata) {
return INSTALL_ERROR_GENERIC;
}
@@ -656,6 +677,49 @@
return INSTALL_OK;
}
+static uint64_t GetPartitionSize(const LpMetadata& metadata, const LpMetadataPartition& partition) {
+ uint64_t total = 0;
+ for (size_t i = 0; i < partition.num_extents; i++) {
+ const auto& extent = metadata.extents[partition.first_extent_index + i];
+ if (extent.target_type != LP_TARGET_TYPE_LINEAR) {
+ LOG(ERROR) << "non-linear extent detected";
+ return 0;
+ }
+ total += extent.num_sectors * LP_SECTOR_SIZE;
+ }
+ return total;
+}
+
+static uint64_t GetPartitionSize(const LpMetadata& metadata, const std::string& name) {
+ for (const auto& partition : metadata.partitions) {
+ if (GetPartitionName(partition) == name) {
+ return GetPartitionSize(metadata, partition);
+ }
+ }
+ return 0;
+}
+
+int GsiService::GetExistingImage(const LpMetadata& metadata, const std::string& name,
+ Image* image) {
+ int error;
+ std::string path = kGsiDataFolder + "/"s + name + ".img"s;
+ auto writer = CreateFiemapWriter(path.c_str(), 0, &error);
+ if (!writer) {
+ return error;
+ }
+
+ // Even after recovering the FIEMAP, we also need to know the exact intended
+ // size of the image, since FiemapWriter may have extended the final block.
+ uint64_t actual_size = GetPartitionSize(metadata, name);
+ if (!actual_size) {
+ LOG(ERROR) << "Could not determine the pre-existing size of " << name;
+ return INSTALL_ERROR_GENERIC;
+ }
+ image->writer = std::move(writer);
+ image->actual_size = actual_size;
+ return INSTALL_OK;
+}
+
bool GsiService::RemoveGsiFiles(bool wipeUserdata) {
std::vector<std::string> files{
kSystemFile,
@@ -719,7 +783,7 @@
LOG(ERROR) << "Error adding " << name << " to partition table";
return nullptr;
}
- if (!AddPartitionFiemap(builder.get(), partition, image.get())) {
+ if (!AddPartitionFiemap(builder.get(), partition, image)) {
return nullptr;
}
}
@@ -756,8 +820,9 @@
}
bool GsiService::AddPartitionFiemap(MetadataBuilder* builder, Partition* partition,
- FiemapWriter* writer) {
- for (const auto& extent : writer->extents()) {
+ const Image& image) {
+ uint64_t sectors_needed = image.actual_size / LP_SECTOR_SIZE;
+ for (const auto& extent : image.writer->extents()) {
// :TODO: block size check for length, not sector size
if (extent.fe_length % LP_SECTOR_SIZE != 0) {
LOG(ERROR) << "Extent is not sector-aligned: " << extent.fe_length;
@@ -767,12 +832,23 @@
LOG(ERROR) << "Extent physical sector is not sector-aligned: " << extent.fe_physical;
return false;
}
- uint64_t num_sectors = extent.fe_length / LP_SECTOR_SIZE;
+
+ uint64_t num_sectors =
+ std::min(static_cast<uint64_t>(extent.fe_length / LP_SECTOR_SIZE), sectors_needed);
+ if (!num_sectors || !sectors_needed) {
+ // This should never happen, but we include it just in case. It would
+ // indicate that the last filesystem block had multiple extents.
+ LOG(WARNING) << "FiemapWriter allocated extra blocks";
+ break;
+ }
+
uint64_t physical_sector = extent.fe_physical / LP_SECTOR_SIZE;
if (!builder->AddLinearExtent(partition, "userdata", num_sectors, physical_sector)) {
LOG(ERROR) << "Could not add extent to lp metadata";
return false;
}
+
+ sectors_needed -= num_sectors;
}
return true;
}
diff --git a/gsi_service.h b/gsi_service.h
index c70618c..d2a87bd 100644
--- a/gsi_service.h
+++ b/gsi_service.h
@@ -62,7 +62,12 @@
private:
using LpMetadata = android::fs_mgr::LpMetadata;
using MetadataBuilder = android::fs_mgr::MetadataBuilder;
- using ImageMap = std::map<std::string, android::fiemap_writer::FiemapUniquePtr>;
+
+ struct Image {
+ android::fiemap_writer::FiemapUniquePtr writer;
+ uint64_t actual_size;
+ };
+ using ImageMap = std::map<std::string, Image>;
int StartInstall(int64_t gsi_size, int64_t userdata_size, bool wipe_userdata);
int PerformSanityChecks();
@@ -76,8 +81,7 @@
int ReenableGsi();
bool DisableGsiInstall();
bool AddPartitionFiemap(android::fs_mgr::MetadataBuilder* builder,
- android::fs_mgr::Partition* partition,
- android::fiemap_writer::FiemapWriter* writer);
+ android::fs_mgr::Partition* partition, const Image& image);
std::unique_ptr<LpMetadata> CreateMetadata(const ImageMap& partitions);
fiemap_writer::FiemapUniquePtr CreateFiemapWriter(const std::string& path, uint64_t size,
int* error);
@@ -88,6 +92,7 @@
void StartAsyncOperation(const std::string& step, int64_t total_bytes);
void UpdateProgress(int status, int64_t bytes_processed);
android::base::unique_fd OpenPartition(const std::string& name);
+ int GetExistingImage(const LpMetadata& metadata, const std::string& name, Image* image);
enum class AccessLevel {
System,
