aosp12/system/incremental_delivery/incfs/incfs.cpp

2145 lines
68 KiB
C++

/*
* Copyright (C) 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "incfs"
#include "incfs.h"
#include <IncrementalProperties.sysprop.h>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/no_destructor.h>
#include <android-base/parsebool.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <libgen.h>
#include <openssl/sha.h>
#include <selinux/android.h>
#include <selinux/selinux.h>
#include <sys/inotify.h>
#include <sys/mount.h>
#include <sys/poll.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/vfs.h>
#include <sys/xattr.h>
#include <unistd.h>
#include <charconv>
#include <chrono>
#include <iterator>
#include <mutex>
#include <optional>
#include <string_view>
#include "MountRegistry.h"
#include "path.h"
using namespace std::literals;
using namespace android::incfs;
using namespace android::sysprop;
namespace ab = android::base;
struct IncFsControl final {
IncFsFd cmd;
IncFsFd pendingReads;
IncFsFd logs;
IncFsFd blocksWritten;
constexpr IncFsControl(IncFsFd cmd, IncFsFd pendingReads, IncFsFd logs, IncFsFd blocksWritten)
: cmd(cmd), pendingReads(pendingReads), logs(logs), blocksWritten(blocksWritten) {}
};
static MountRegistry& registry() {
static ab::NoDestructor<MountRegistry> instance{};
return *instance;
}
static ab::unique_fd openRaw(std::string_view file) {
auto fd = ab::unique_fd(::open(details::c_str(file), O_RDONLY | O_CLOEXEC));
if (fd < 0) {
return ab::unique_fd{-errno};
}
return fd;
}
static ab::unique_fd openAt(int fd, std::string_view name, int flags = 0) {
auto res = ab::unique_fd(
::openat(fd, details::c_str(name), O_RDONLY | O_CLOEXEC | O_NOFOLLOW | flags));
if (res < 0) {
return ab::unique_fd{-errno};
}
return res;
}
static std::string indexPath(std::string_view root, IncFsFileId fileId) {
return path::join(root, INCFS_INDEX_NAME, toString(fileId));
}
static std::string rootForCmd(int fd) {
auto cmdFile = path::fromFd(fd);
if (cmdFile.empty()) {
LOG(INFO) << __func__ << "(): name empty for " << fd;
return {};
}
auto res = path::dirName(cmdFile);
if (res.empty()) {
LOG(INFO) << __func__ << "(): dirname empty for " << cmdFile;
return {};
}
if (!path::endsWith(cmdFile, INCFS_PENDING_READS_FILENAME)) {
LOG(INFO) << __func__ << "(): invalid file name " << cmdFile;
return {};
}
if (cmdFile.data() == res.data() || cmdFile.starts_with(res)) {
cmdFile.resize(res.size());
return cmdFile;
}
return std::string(res);
}
static bool isFsAvailable() {
static const char kProcFilesystems[] = "/proc/filesystems";
std::string filesystems;
if (!ab::ReadFileToString(kProcFilesystems, &filesystems)) {
return false;
}
const auto result = filesystems.find("\t" INCFS_NAME "\n") != std::string::npos;
LOG(INFO) << "isFsAvailable: " << (result ? "true" : "false");
return result;
}
static int getFirstApiLevel() {
uint64_t api_level = android::base::GetUintProperty<uint64_t>("ro.product.first_api_level", 0);
LOG(INFO) << "Initial API level of the device: " << api_level;
return api_level;
}
static std::string_view incFsPropertyValue() {
constexpr const int R_API = 30;
static const auto kDefaultValue{getFirstApiLevel() > R_API ? "on" : ""};
static const ab::NoDestructor<std::string> kValue{
IncrementalProperties::enable().value_or(kDefaultValue)};
LOG(INFO) << "ro.incremental.enable: " << *kValue;
return *kValue;
}
static std::pair<bool, std::string_view> parseProperty(std::string_view property) {
auto boolVal = ab::ParseBool(property);
if (boolVal == ab::ParseBoolResult::kTrue) {
return {isFsAvailable(), {}};
}
if (boolVal == ab::ParseBoolResult::kFalse) {
return {false, {}};
}
// Don't load the module at once, but instead only check if it is loadable.
static const auto kModulePrefix = "module:"sv;
if (property.starts_with(kModulePrefix)) {
const auto modulePath = property.substr(kModulePrefix.size());
return {::access(details::c_str(modulePath), R_OK | X_OK), modulePath};
}
return {false, {}};
}
template <class Callback>
static IncFsErrorCode forEachFileIn(std::string_view dirPath, Callback cb) {
auto dir = path::openDir(details::c_str(dirPath));
if (!dir) {
return -EINVAL;
}
int res = 0;
while (auto entry = (errno = 0, ::readdir(dir.get()))) {
if (entry->d_type != DT_REG) {
continue;
}
++res;
if (!cb(entry->d_name)) {
break;
}
}
if (errno) {
return -errno;
}
return res;
}
namespace {
class IncFsInit {
public:
IncFsInit() {
auto [featureEnabled, moduleName] = parseProperty(incFsPropertyValue());
featureEnabled_ = featureEnabled;
moduleName_ = moduleName;
loaded_ = featureEnabled_ && isFsAvailable();
}
constexpr ~IncFsInit() = default;
bool enabled() const { return featureEnabled_; }
bool enabledAndReady() const {
if (!featureEnabled_) {
return false;
}
if (moduleName_.empty()) {
return true;
}
if (loaded_) {
return true;
}
std::call_once(loadedFlag_, [this] {
if (isFsAvailable()) {
// Loaded from a different process, I suppose.
loaded_ = true;
LOG(INFO) << "IncFS is already available, skipped loading";
return;
}
const ab::unique_fd fd(TEMP_FAILURE_RETRY(
::open(details::c_str(moduleName_), O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
if (fd < 0) {
PLOG(ERROR) << "could not open IncFs kernel module \"" << moduleName_ << '"';
return;
}
const auto rc = syscall(__NR_finit_module, fd.get(), "", 0);
if (rc < 0) {
PLOG(ERROR) << "finit_module for IncFs \"" << moduleName_ << "\" failed";
return;
}
if (!isFsAvailable()) {
LOG(ERROR) << "loaded IncFs kernel module \"" << moduleName_
<< "\" but incremental-fs is still not available";
}
loaded_ = true;
LOG(INFO) << "successfully loaded IncFs kernel module \"" << moduleName_ << '"';
});
return loaded_;
}
private:
bool featureEnabled_;
std::string_view moduleName_;
mutable std::once_flag loadedFlag_;
mutable bool loaded_;
};
} // namespace
static IncFsInit& init() {
static IncFsInit initer;
return initer;
}
bool IncFs_IsEnabled() {
return init().enabled();
}
static Features readIncFsFeatures() {
init().enabledAndReady();
int res = Features::none | Features::mappingFilesProgressFixed;
static const char kSysfsFeaturesDir[] = "/sys/fs/" INCFS_NAME "/features";
const auto dir = path::openDir(kSysfsFeaturesDir);
if (!dir) {
PLOG(ERROR) << "IncFs_Features: failed to open features dir, assuming v1/none.";
return Features(res);
}
while (auto entry = ::readdir(dir.get())) {
if (entry->d_type != DT_REG) {
continue;
}
if (entry->d_name == "corefs"sv) {
res |= Features::core;
} else if (entry->d_name == "v2"sv || entry->d_name == "report_uid"sv) {
res |= Features::v2;
}
}
LOG(INFO) << "IncFs_Features: " << ((res & Features::v2) ? "v2" : "v1");
return Features(res);
}
IncFsFeatures IncFs_Features() {
static const auto features = IncFsFeatures(readIncFsFeatures());
return features;
}
bool isIncFsFdImpl(int fd) {
struct statfs fs = {};
if (::fstatfs(fd, &fs) != 0) {
PLOG(WARNING) << __func__ << "(): could not fstatfs fd " << fd;
return false;
}
return fs.f_type == (decltype(fs.f_type))INCFS_MAGIC_NUMBER;
}
bool isIncFsPathImpl(const char* path) {
struct statfs fs = {};
if (::statfs(path, &fs) != 0) {
PLOG(WARNING) << __func__ << "(): could not statfs " << path;
return false;
}
return fs.f_type == (decltype(fs.f_type))INCFS_MAGIC_NUMBER;
}
static int isDir(const char* path) {
struct stat st;
if (::stat(path, &st) != 0) {
return -errno;
}
if (!S_ISDIR(st.st_mode)) {
return -ENOTDIR;
}
return 0;
}
static bool isAbsolute(const char* path) {
return path && path[0] == '/';
}
static int isValidMountTarget(const char* path) {
if (!isAbsolute(path)) {
return -EINVAL;
}
if (isIncFsPath(path)) {
LOG(ERROR) << "[incfs] mounting over existing incfs mount is not allowed";
return -EINVAL;
}
if (const auto err = isDir(path); err != 0) {
return err;
}
if (const auto err = path::isEmptyDir(path); err != 0) {
return err;
}
return 0;
}
static int rmDirContent(int dirFd) {
auto dir = path::openDir(dirFd);
if (!dir) {
return -errno;
}
while (auto entry = ::readdir(dir.get())) {
if (entry->d_name == "."sv || entry->d_name == ".."sv) {
continue;
}
if (entry->d_type == DT_DIR) {
auto fd = openAt(dirFd, entry->d_name, O_DIRECTORY);
if (!fd.ok()) {
return -errno;
}
if (const auto err = rmDirContent(fd.get())) {
return err;
}
if (::unlinkat(fd.get(), entry->d_name, AT_REMOVEDIR)) {
return -errno;
}
} else {
auto fd = openAt(dirFd, entry->d_name);
if (!fd.ok()) {
return -errno;
}
if (::unlinkat(fd.get(), entry->d_name, 0)) {
return -errno;
}
}
}
return 0;
}
static int rmDirContent(const char* path) {
auto fd = openAt(-1, path, O_DIRECTORY);
if (!fd.ok()) {
return -errno;
}
return rmDirContent(fd.get());
}
static std::string makeMountOptionsString(IncFsMountOptions options) {
auto opts = ab::StringPrintf("read_timeout_ms=%u,readahead=0,rlog_pages=%u,rlog_wakeup_cnt=1,",
unsigned(options.defaultReadTimeoutMs),
unsigned(options.readLogBufferPages < 0
? INCFS_DEFAULT_PAGE_READ_BUFFER_PAGES
: options.readLogBufferPages));
if (features() & Features::v2) {
ab::StringAppendF(&opts, "report_uid,");
if (options.sysfsName && *options.sysfsName) {
ab::StringAppendF(&opts, "sysfs_name=%s,", options.sysfsName);
}
}
return opts;
}
static IncFsControl* makeControl(int fd) {
auto cmd = openAt(fd, INCFS_PENDING_READS_FILENAME);
if (!cmd.ok()) {
return nullptr;
}
ab::unique_fd pendingReads(fcntl(cmd.get(), F_DUPFD_CLOEXEC, cmd.get()));
if (!pendingReads.ok()) {
return nullptr;
}
auto logs = openAt(fd, INCFS_LOG_FILENAME);
if (!logs.ok()) {
return nullptr;
}
ab::unique_fd blocksWritten;
if (features() & Features::v2) {
blocksWritten = openAt(fd, INCFS_BLOCKS_WRITTEN_FILENAME);
if (!blocksWritten.ok()) {
return nullptr;
}
}
auto control =
IncFs_CreateControl(cmd.get(), pendingReads.get(), logs.get(), blocksWritten.get());
if (control) {
(void)cmd.release();
(void)pendingReads.release();
(void)logs.release();
(void)blocksWritten.release();
} else {
errno = ENOMEM;
}
return control;
}
static std::string makeCommandPath(std::string_view root, std::string_view item) {
auto [itemRoot, subpath] = registry().rootAndSubpathFor(item);
if (itemRoot != root) {
return {};
}
// TODO: add "/.cmd/" if we decide to use a separate control tree.
return path::join(itemRoot, subpath);
}
static void toString(IncFsFileId id, char* out) {
// Make sure this function matches the one in the kernel (e.g. same case for a-f digits).
static constexpr char kHexChar[] = "0123456789abcdef";
for (auto item = std::begin(id.data); item != std::end(id.data); ++item, out += 2) {
out[0] = kHexChar[(*item & 0xf0) >> 4];
out[1] = kHexChar[(*item & 0x0f)];
}
}
static std::string toStringImpl(IncFsFileId id) {
std::string res(kIncFsFileIdStringLength, '\0');
toString(id, res.data());
return res;
}
static IncFsFileId toFileIdImpl(std::string_view str) {
if (str.size() != kIncFsFileIdStringLength) {
return kIncFsInvalidFileId;
}
IncFsFileId res;
auto out = (char*)&res;
for (auto it = str.begin(); it != str.end(); it += 2, ++out) {
static const auto fromChar = [](char src) -> int {
if (src >= '0' && src <= '9') {
return src - '0';
}
if (src >= 'a' && src <= 'f') {
return src - 'a' + 10;
}
return -1;
};
const int c[2] = {fromChar(it[0]), fromChar(it[1])};
if (c[0] == -1 || c[1] == -1) {
errno = EINVAL;
return kIncFsInvalidFileId;
}
*out = (c[0] << 4) | c[1];
}
return res;
}
int IncFs_FileIdToString(IncFsFileId id, char* out) {
if (!out) {
return -EINVAL;
}
toString(id, out);
return 0;
}
IncFsFileId IncFs_FileIdFromString(const char* in) {
return toFileIdImpl({in, kIncFsFileIdStringLength});
}
IncFsFileId IncFs_FileIdFromMetadata(IncFsSpan metadata) {
IncFsFileId id = {};
if (size_t(metadata.size) <= sizeof(id)) {
memcpy(&id, metadata.data, metadata.size);
} else {
uint8_t buffer[SHA_DIGEST_LENGTH];
static_assert(sizeof(buffer) >= sizeof(id));
SHA_CTX ctx;
SHA1_Init(&ctx);
SHA1_Update(&ctx, metadata.data, metadata.size);
SHA1_Final(buffer, &ctx);
memcpy(&id, buffer, sizeof(id));
}
return id;
}
static bool restoreconControlFiles(std::string_view targetDir) {
static constexpr auto restorecon = [](const char* name) {
if (const auto err = selinux_android_restorecon(name, SELINUX_ANDROID_RESTORECON_FORCE);
err != 0) {
errno = -err;
PLOG(ERROR) << "[incfs] Failed to restorecon: " << name;
return false;
}
return true;
};
if (!restorecon(path::join(targetDir, INCFS_PENDING_READS_FILENAME).c_str())) {
return false;
}
if (!restorecon(path::join(targetDir, INCFS_LOG_FILENAME).c_str())) {
return false;
}
if ((features() & Features::v2) &&
!restorecon(path::join(targetDir, INCFS_BLOCKS_WRITTEN_FILENAME).c_str())) {
return false;
}
return true;
}
IncFsControl* IncFs_Mount(const char* backingPath, const char* targetDir,
IncFsMountOptions options) {
if (!init().enabledAndReady()) {
LOG(WARNING) << "[incfs] Feature is not enabled";
errno = ENOTSUP;
return nullptr;
}
if (auto err = isValidMountTarget(targetDir); err != 0) {
errno = -err;
return nullptr;
}
if (!isAbsolute(backingPath)) {
errno = EINVAL;
return nullptr;
}
if (options.flags & createOnly) {
if (const auto err = path::isEmptyDir(backingPath); err != 0) {
errno = -err;
return nullptr;
}
} else if (options.flags & android::incfs::truncate) {
if (const auto err = rmDirContent(backingPath); err != 0) {
errno = -err;
return nullptr;
}
}
const auto opts = makeMountOptionsString(options);
if (::mount(backingPath, targetDir, INCFS_NAME, MS_NOSUID | MS_NODEV | MS_NOATIME,
opts.c_str())) {
PLOG(ERROR) << "[incfs] Failed to mount IncFS filesystem: " << targetDir;
return nullptr;
}
// in case when the path is given in a form of a /proc/.../fd/ link, we need to update
// it here: old fd refers to the original empty directory, not to the mount
std::string updatedTargetDir;
if (path::dirName(targetDir) == path::procfsFdDir) {
updatedTargetDir = path::readlink(targetDir);
} else {
updatedTargetDir = targetDir;
}
auto rootFd = ab::unique_fd(::open(updatedTargetDir.c_str(), O_PATH | O_CLOEXEC | O_DIRECTORY));
if (updatedTargetDir != targetDir) {
// ensure that the new directory is still the same after reopening
if (path::fromFd(rootFd) != updatedTargetDir) {
errno = EINVAL;
return nullptr;
}
}
if (!restoreconControlFiles(path::procfsForFd(rootFd))) {
(void)IncFs_Unmount(targetDir);
return nullptr;
}
auto control = makeControl(rootFd);
if (control == nullptr) {
(void)IncFs_Unmount(targetDir);
return nullptr;
}
return control;
}
IncFsControl* IncFs_Open(const char* dir) {
auto root = registry().rootFor(dir);
if (root.empty()) {
errno = EINVAL;
return nullptr;
}
auto rootFd = ab::unique_fd(::open(details::c_str(root), O_PATH | O_CLOEXEC | O_DIRECTORY));
return makeControl(rootFd);
}
IncFsFd IncFs_GetControlFd(const IncFsControl* control, IncFsFdType type) {
if (!control) {
return -EINVAL;
}
switch (type) {
case CMD:
return control->cmd;
case PENDING_READS:
return control->pendingReads;
case LOGS:
return control->logs;
case BLOCKS_WRITTEN:
return control->blocksWritten;
default:
return -EINVAL;
}
}
IncFsSize IncFs_ReleaseControlFds(IncFsControl* control, IncFsFd out[], IncFsSize outSize) {
if (!control || !out) {
return -EINVAL;
}
if (outSize < IncFsFdType::FDS_COUNT) {
return -ERANGE;
}
out[CMD] = std::exchange(control->cmd, -1);
out[PENDING_READS] = std::exchange(control->pendingReads, -1);
out[LOGS] = std::exchange(control->logs, -1);
out[BLOCKS_WRITTEN] = std::exchange(control->blocksWritten, -1);
return IncFsFdType::FDS_COUNT;
}
IncFsControl* IncFs_CreateControl(IncFsFd cmd, IncFsFd pendingReads, IncFsFd logs,
IncFsFd blocksWritten) {
return new IncFsControl(cmd, pendingReads, logs, blocksWritten);
}
void IncFs_DeleteControl(IncFsControl* control) {
if (control) {
if (control->cmd >= 0) {
close(control->cmd);
}
if (control->pendingReads >= 0) {
close(control->pendingReads);
}
if (control->logs >= 0) {
close(control->logs);
}
if (control->blocksWritten >= 0) {
close(control->blocksWritten);
}
delete control;
}
}
IncFsErrorCode IncFs_SetOptions(const IncFsControl* control, IncFsMountOptions options) {
if (!control) {
return -EINVAL;
}
auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto opts = makeMountOptionsString(options);
if (::mount(nullptr, root.c_str(), nullptr, MS_REMOUNT | MS_NOSUID | MS_NODEV | MS_NOATIME,
opts.c_str()) != 0) {
const auto error = errno;
PLOG(ERROR) << "[incfs] Failed to remount IncFS filesystem: " << root;
return -error;
}
return 0;
}
IncFsErrorCode IncFs_Root(const IncFsControl* control, char buffer[], size_t* bufferSize) {
if (!control) {
return -EINVAL;
}
std::string result = rootForCmd(control->cmd);
if (*bufferSize <= result.size()) {
*bufferSize = result.size() + 1;
return -EOVERFLOW;
}
result.copy(buffer, result.size());
buffer[result.size()] = '\0';
*bufferSize = result.size();
return 0;
}
template <class T>
std::optional<T> read(IncFsSpan& data) {
if (data.size < (int32_t)sizeof(T)) {
return {};
}
T res;
memcpy(&res, data.data, sizeof(res));
data.data += sizeof(res);
data.size -= sizeof(res);
return res;
}
static IncFsErrorCode validateSignatureFormat(IncFsSpan signature) {
if (signature.data == nullptr && signature.size == 0) {
return 0; // it's fine to have unverified files too
}
if ((signature.data == nullptr) != (signature.size == 0)) {
return -EINVAL;
}
// These structs are here purely for checking the minimum size. Maybe will use them for
// parsing later.
struct __attribute__((packed)) Hashing {
int32_t size;
int32_t algorithm;
int8_t log2_blocksize;
int32_t salt_size;
int32_t raw_root_hash_size;
};
struct __attribute__((packed)) Signing {
int32_t size;
int32_t apk_digest_size;
int32_t certificate_size;
int32_t addl_data_size;
int32_t public_key_size;
int32_t algorithm;
int32_t signature_size;
};
struct __attribute__((packed)) MinSignature {
int32_t version;
Hashing hashing_info;
Signing signing_info;
};
if (signature.size < (int32_t)sizeof(MinSignature)) {
return -ERANGE;
}
if (signature.size > INCFS_MAX_SIGNATURE_SIZE) {
return -ERANGE;
}
auto version = read<int32_t>(signature);
if (version.value_or(-1) != INCFS_SIGNATURE_VERSION) {
return -EINVAL;
}
auto hashSize = read<int32_t>(signature);
if (!hashSize || signature.size < *hashSize) {
return -EINVAL;
}
auto hashAlgo = read<int32_t>(signature);
if (hashAlgo.value_or(-1) != INCFS_HASH_TREE_SHA256) {
return -EINVAL;
}
auto logBlockSize = read<int8_t>(signature);
if (logBlockSize.value_or(-1) != 12 /* 2^12 == 4096 */) {
return -EINVAL;
}
auto saltSize = read<int32_t>(signature);
if (saltSize.value_or(-1) != 0) {
return -EINVAL;
}
auto rootHashSize = read<int32_t>(signature);
if (rootHashSize.value_or(-1) != INCFS_MAX_HASH_SIZE) {
return -EINVAL;
}
if (signature.size < *rootHashSize) {
return -EINVAL;
}
signature.data += *rootHashSize;
signature.size -= *rootHashSize;
auto signingSize = read<int32_t>(signature);
// everything remaining has to be in the signing info
if (signingSize.value_or(-1) != signature.size) {
return -EINVAL;
}
// TODO: validate the signature part too.
return 0;
}
IncFsErrorCode IncFs_MakeFile(const IncFsControl* control, const char* path, int32_t mode,
IncFsFileId id, IncFsNewFileParams params) {
if (!control) {
return -EINVAL;
}
auto [root, subpath] = registry().rootAndSubpathFor(path);
if (root.empty()) {
PLOG(WARNING) << "[incfs] makeFile failed for path " << path << ", root is empty.";
return -EINVAL;
}
if (params.size < 0) {
LOG(WARNING) << "[incfs] makeFile failed for path " << path
<< ", size is invalid: " << params.size;
return -ERANGE;
}
const auto [subdir, name] = path::splitDirBase(subpath);
incfs_new_file_args args = {
.size = (uint64_t)params.size,
.mode = (uint16_t)mode,
.directory_path = (uint64_t)subdir.data(),
.file_name = (uint64_t)name.data(),
.file_attr = (uint64_t)params.metadata.data,
.file_attr_len = (uint32_t)params.metadata.size,
};
static_assert(sizeof(args.file_id.bytes) == sizeof(id.data));
memcpy(args.file_id.bytes, id.data, sizeof(args.file_id.bytes));
if (auto err = validateSignatureFormat(params.signature)) {
return err;
}
args.signature_info = (uint64_t)(uintptr_t)params.signature.data;
args.signature_size = (uint64_t)params.signature.size;
if (::ioctl(control->cmd, INCFS_IOC_CREATE_FILE, &args)) {
PLOG(WARNING) << "[incfs] makeFile failed for " << root << " / " << subdir << " / " << name
<< " of " << params.size << " bytes";
return -errno;
}
if (::chmod(path::join(root, subdir, name).c_str(), mode)) {
PLOG(WARNING) << "[incfs] couldn't change file mode to 0" << std::oct << mode;
}
return 0;
}
IncFsErrorCode IncFs_MakeMappedFile(const IncFsControl* control, const char* path, int32_t mode,
IncFsNewMappedFileParams params) {
if (!control) {
return -EINVAL;
}
auto [root, subpath] = registry().rootAndSubpathFor(path);
if (root.empty()) {
PLOG(WARNING) << "[incfs] makeMappedFile failed for path " << path << ", root is empty.";
return -EINVAL;
}
if (params.size < 0) {
LOG(WARNING) << "[incfs] makeMappedFile failed for path " << path
<< ", size is invalid: " << params.size;
return -ERANGE;
}
const auto [subdir, name] = path::splitDirBase(subpath);
incfs_create_mapped_file_args args = {
.size = (uint64_t)params.size,
.mode = (uint16_t)mode,
.directory_path = (uint64_t)subdir.data(),
.file_name = (uint64_t)name.data(),
.source_offset = (uint64_t)params.sourceOffset,
};
static_assert(sizeof(args.source_file_id.bytes) == sizeof(params.sourceId.data));
memcpy(args.source_file_id.bytes, params.sourceId.data, sizeof(args.source_file_id.bytes));
if (::ioctl(control->cmd, INCFS_IOC_CREATE_MAPPED_FILE, &args)) {
PLOG(WARNING) << "[incfs] makeMappedFile failed for " << root << " / " << subdir << " / "
<< name << " of " << params.size << " bytes starting at "
<< params.sourceOffset;
return -errno;
}
if (::chmod(path::join(root, subpath).c_str(), mode)) {
PLOG(WARNING) << "[incfs] makeMappedFile error: couldn't change file mode to 0" << std::oct
<< mode;
}
return 0;
}
static IncFsErrorCode makeDir(const char* commandPath, int32_t mode, bool allowExisting) {
if (!::mkdir(commandPath, mode)) {
if (::chmod(commandPath, mode)) {
PLOG(WARNING) << "[incfs] couldn't change directory mode to 0" << std::oct << mode;
}
return 0;
}
// don't touch the existing dir's mode - mkdir(1) works that way.
return (allowExisting && errno == EEXIST) ? 0 : -errno;
}
static IncFsErrorCode makeDirs(std::string_view commandPath, std::string_view path,
std::string_view root, int32_t mode) {
auto commandCPath = details::c_str(commandPath);
const auto mkdirRes = makeDir(commandCPath, mode, true);
if (!mkdirRes) {
return 0;
}
if (mkdirRes != -ENOENT) {
LOG(ERROR) << __func__ << "(): mkdir failed for " << path << " - " << mkdirRes;
return mkdirRes;
}
const auto parent = path::dirName(commandPath);
if (!path::startsWith(parent, root)) {
// went too far, already out of the root mount
return -EINVAL;
}
if (auto parentMkdirRes = makeDirs(parent, path::dirName(path), root, mode)) {
return parentMkdirRes;
}
return makeDir(commandCPath, mode, true);
}
IncFsErrorCode IncFs_MakeDir(const IncFsControl* control, const char* path, int32_t mode) {
if (!control) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
LOG(ERROR) << __func__ << "(): root is empty for " << path;
return -EINVAL;
}
auto commandPath = makeCommandPath(root, path);
if (commandPath.empty()) {
LOG(ERROR) << __func__ << "(): commandPath is empty for " << path;
return -EINVAL;
}
if (auto res = makeDir(commandPath.c_str(), mode, false)) {
LOG(ERROR) << __func__ << "(): mkdir failed for " << commandPath << " - " << res;
return res;
}
return 0;
}
IncFsErrorCode IncFs_MakeDirs(const IncFsControl* control, const char* path, int32_t mode) {
if (!control) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
LOG(ERROR) << __func__ << "(): root is empty for " << path;
return -EINVAL;
}
auto commandPath = makeCommandPath(root, path);
if (commandPath.empty()) {
LOG(ERROR) << __func__ << "(): commandPath is empty for " << path;
return -EINVAL;
}
return makeDirs(commandPath, path, root, mode);
}
static IncFsErrorCode getMetadata(const char* path, char buffer[], size_t* bufferSize) {
const auto res = ::getxattr(path, kMetadataAttrName, buffer, *bufferSize);
if (res < 0) {
if (errno == ERANGE) {
auto neededSize = ::getxattr(path, kMetadataAttrName, buffer, 0);
if (neededSize >= 0) {
*bufferSize = neededSize;
return 0;
}
}
return -errno;
}
*bufferSize = res;
return 0;
}
IncFsErrorCode IncFs_GetMetadataById(const IncFsControl* control, IncFsFileId fileId, char buffer[],
size_t* bufferSize) {
if (!control) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto name = indexPath(root, fileId);
return getMetadata(details::c_str(name), buffer, bufferSize);
}
IncFsErrorCode IncFs_GetMetadataByPath(const IncFsControl* control, const char* path, char buffer[],
size_t* bufferSize) {
if (!control) {
return -EINVAL;
}
const auto pathRoot = registry().rootFor(path);
const auto root = rootForCmd(control->cmd);
if (root.empty() || root != pathRoot) {
return -EINVAL;
}
return getMetadata(path, buffer, bufferSize);
}
template <class GetterFunc, class Param>
static IncFsFileId getId(GetterFunc getter, Param param) {
char buffer[kIncFsFileIdStringLength];
const auto res = getter(param, kIdAttrName, buffer, sizeof(buffer));
if (res != sizeof(buffer)) {
return kIncFsInvalidFileId;
}
return toFileIdImpl({buffer, std::size(buffer)});
}
IncFsFileId IncFs_GetId(const IncFsControl* control, const char* path) {
if (!control) {
return kIncFsInvalidFileId;
}
const auto pathRoot = registry().rootFor(path);
const auto root = rootForCmd(control->cmd);
if (root.empty() || root != pathRoot) {
errno = EINVAL;
return kIncFsInvalidFileId;
}
return getId(::getxattr, path);
}
static IncFsErrorCode getSignature(int fd, char buffer[], size_t* bufferSize) {
incfs_get_file_sig_args args = {
.file_signature = (uint64_t)buffer,
.file_signature_buf_size = (uint32_t)*bufferSize,
};
auto res = ::ioctl(fd, INCFS_IOC_READ_FILE_SIGNATURE, &args);
if (res < 0) {
if (errno == E2BIG) {
*bufferSize = INCFS_MAX_SIGNATURE_SIZE;
}
return -errno;
}
*bufferSize = args.file_signature_len_out;
return 0;
}
IncFsErrorCode IncFs_GetSignatureById(const IncFsControl* control, IncFsFileId fileId,
char buffer[], size_t* bufferSize) {
if (!control) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto file = indexPath(root, fileId);
auto fd = openRaw(file);
if (fd < 0) {
return fd.get();
}
return getSignature(fd, buffer, bufferSize);
}
IncFsErrorCode IncFs_GetSignatureByPath(const IncFsControl* control, const char* path,
char buffer[], size_t* bufferSize) {
if (!control) {
return -EINVAL;
}
const auto pathRoot = registry().rootFor(path);
const auto root = rootForCmd(control->cmd);
if (root.empty() || root != pathRoot) {
return -EINVAL;
}
return IncFs_UnsafeGetSignatureByPath(path, buffer, bufferSize);
}
IncFsErrorCode IncFs_UnsafeGetSignatureByPath(const char* path, char buffer[], size_t* bufferSize) {
if (!isIncFsPath(path)) {
return -EINVAL;
}
auto fd = openRaw(path);
if (fd < 0) {
return fd.get();
}
return getSignature(fd, buffer, bufferSize);
}
IncFsErrorCode IncFs_Link(const IncFsControl* control, const char* fromPath,
const char* wherePath) {
if (!control) {
return -EINVAL;
}
auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto cmdFrom = makeCommandPath(root, fromPath);
if (cmdFrom.empty()) {
return -EINVAL;
}
auto cmdWhere = makeCommandPath(root, wherePath);
if (cmdWhere.empty()) {
return -EINVAL;
}
if (::link(cmdFrom.c_str(), cmdWhere.c_str())) {
return -errno;
}
return 0;
}
IncFsErrorCode IncFs_Unlink(const IncFsControl* control, const char* path) {
if (!control) {
return -EINVAL;
}
auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto cmdPath = makeCommandPath(root, path);
if (cmdPath.empty()) {
return -EINVAL;
}
if (::unlink(cmdPath.c_str())) {
if (errno == EISDIR) {
if (!::rmdir(cmdPath.c_str())) {
return 0;
}
}
return -errno;
}
return 0;
}
template <class RawPendingRead>
static int waitForReadsImpl(int fd, int32_t timeoutMs, RawPendingRead pendingReadsBuffer[],
size_t* pendingReadsBufferSize) {
using namespace std::chrono;
auto hrTimeout = steady_clock::duration(milliseconds(timeoutMs));
while (hrTimeout > hrTimeout.zero() || (!pendingReadsBuffer && hrTimeout == hrTimeout.zero())) {
const auto startTs = steady_clock::now();
pollfd pfd = {fd, POLLIN, 0};
const auto res = ::poll(&pfd, 1, duration_cast<milliseconds>(hrTimeout).count());
if (res > 0) {
break;
}
if (res == 0) {
if (pendingReadsBufferSize) {
*pendingReadsBufferSize = 0;
}
return -ETIMEDOUT;
}
const auto error = errno;
if (error != EINTR) {
PLOG(ERROR) << "poll() failed";
return -error;
}
hrTimeout -= steady_clock::now() - startTs;
}
if (!pendingReadsBuffer) {
return hrTimeout < hrTimeout.zero() ? -ETIMEDOUT : 0;
}
auto res =
::read(fd, pendingReadsBuffer, *pendingReadsBufferSize * sizeof(*pendingReadsBuffer));
if (res < 0) {
const auto error = errno;
PLOG(ERROR) << "read() failed";
return -error;
}
if (res == 0) {
*pendingReadsBufferSize = 0;
return -ETIMEDOUT;
}
if ((res % sizeof(*pendingReadsBuffer)) != 0) {
PLOG(ERROR) << "read() returned half of a struct??";
return -EFAULT;
}
*pendingReadsBufferSize = res / sizeof(*pendingReadsBuffer);
return 0;
}
template <class PublicPendingRead, class RawPendingRead>
PublicPendingRead convertRead(RawPendingRead rawRead) {
PublicPendingRead res = {
.bootClockTsUs = rawRead.timestamp_us,
.block = (IncFsBlockIndex)rawRead.block_index,
.serialNo = rawRead.serial_number,
};
memcpy(&res.id.data, rawRead.file_id.bytes, sizeof(res.id.data));
if constexpr (std::is_same_v<PublicPendingRead, IncFsReadInfoWithUid>) {
if constexpr (std::is_same_v<RawPendingRead, incfs_pending_read_info2>) {
res.uid = rawRead.uid;
} else {
res.uid = kIncFsNoUid;
}
}
return res;
}
template <class RawPendingRead, class PublicPendingRead>
static int waitForReads(IncFsFd readFd, int32_t timeoutMs, PublicPendingRead buffer[],
size_t* bufferSize) {
std::vector<RawPendingRead> pendingReads(*bufferSize);
if (const auto res = waitForReadsImpl(readFd, timeoutMs, pendingReads.data(), bufferSize)) {
return res;
}
for (size_t i = 0; i != *bufferSize; ++i) {
buffer[i] = convertRead<PublicPendingRead>(pendingReads[i]);
}
return 0;
}
template <class PublicPendingRead>
static int waitForReads(IncFsFd readFd, int32_t timeoutMs, PublicPendingRead buffer[],
size_t* bufferSize) {
if (features() & Features::v2) {
return waitForReads<incfs_pending_read_info2>(readFd, timeoutMs, buffer, bufferSize);
}
return waitForReads<incfs_pending_read_info>(readFd, timeoutMs, buffer, bufferSize);
}
IncFsErrorCode IncFs_WaitForPendingReads(const IncFsControl* control, int32_t timeoutMs,
IncFsReadInfo buffer[], size_t* bufferSize) {
if (!control || control->pendingReads < 0) {
return -EINVAL;
}
return waitForReads(control->pendingReads, timeoutMs, buffer, bufferSize);
}
IncFsErrorCode IncFs_WaitForPendingReadsWithUid(const IncFsControl* control, int32_t timeoutMs,
IncFsReadInfoWithUid buffer[], size_t* bufferSize) {
if (!control || control->pendingReads < 0) {
return -EINVAL;
}
return waitForReads(control->pendingReads, timeoutMs, buffer, bufferSize);
}
IncFsErrorCode IncFs_WaitForPageReads(const IncFsControl* control, int32_t timeoutMs,
IncFsReadInfo buffer[], size_t* bufferSize) {
if (!control || control->logs < 0) {
return -EINVAL;
}
return waitForReads(control->logs, timeoutMs, buffer, bufferSize);
}
IncFsErrorCode IncFs_WaitForPageReadsWithUid(const IncFsControl* control, int32_t timeoutMs,
IncFsReadInfoWithUid buffer[], size_t* bufferSize) {
if (!control || control->logs < 0) {
return -EINVAL;
}
return waitForReads(control->logs, timeoutMs, buffer, bufferSize);
}
static IncFsFd openForSpecialOps(int cmd, const char* path) {
ab::unique_fd fd(::open(path, O_RDONLY | O_CLOEXEC));
if (fd < 0) {
return -errno;
}
struct incfs_permit_fill args = {.file_descriptor = (uint32_t)fd.get()};
auto err = ::ioctl(cmd, INCFS_IOC_PERMIT_FILL, &args);
if (err < 0) {
return -errno;
}
return fd.release();
}
IncFsFd IncFs_OpenForSpecialOpsByPath(const IncFsControl* control, const char* path) {
if (!control) {
return -EINVAL;
}
const auto pathRoot = registry().rootFor(path);
const auto cmd = control->cmd;
const auto root = rootForCmd(cmd);
if (root.empty() || root != pathRoot) {
return -EINVAL;
}
return openForSpecialOps(cmd, makeCommandPath(root, path).c_str());
}
IncFsFd IncFs_OpenForSpecialOpsById(const IncFsControl* control, IncFsFileId id) {
if (!control) {
return -EINVAL;
}
const auto cmd = control->cmd;
const auto root = rootForCmd(cmd);
if (root.empty()) {
return -EINVAL;
}
auto name = indexPath(root, id);
return openForSpecialOps(cmd, makeCommandPath(root, name).c_str());
}
static int writeBlocks(int fd, const incfs_fill_block blocks[], int blocksCount) {
if (fd < 0 || blocksCount == 0) {
return 0;
}
if (blocksCount < 0) {
return -EINVAL;
}
auto ptr = blocks;
const auto end = blocks + blocksCount;
do {
struct incfs_fill_blocks args = {.count = uint64_t(end - ptr),
.fill_blocks = (uint64_t)(uintptr_t)ptr};
const auto written = ::ioctl(fd, INCFS_IOC_FILL_BLOCKS, &args);
if (written < 0) {
if (errno == EINTR) {
continue;
}
const auto error = errno;
PLOG(WARNING) << "writing IncFS blocks failed";
if (ptr == blocks) {
return -error;
}
// something has been written, return a success here and let the
// next call handle the error.
break;
}
ptr += written;
} while (ptr < end);
return ptr - blocks;
}
IncFsErrorCode IncFs_WriteBlocks(const IncFsDataBlock blocks[], size_t blocksCount) {
incfs_fill_block incfsBlocks[128];
int writtenCount = 0;
int incfsBlocksUsed = 0;
int lastBlockFd = -1;
for (size_t i = 0; i < blocksCount; ++i) {
if (lastBlockFd != blocks[i].fileFd || incfsBlocksUsed == std::size(incfsBlocks)) {
auto count = writeBlocks(lastBlockFd, incfsBlocks, incfsBlocksUsed);
if (count > 0) {
writtenCount += count;
}
if (count != incfsBlocksUsed) {
return writtenCount ? writtenCount : count;
}
lastBlockFd = blocks[i].fileFd;
incfsBlocksUsed = 0;
}
incfsBlocks[incfsBlocksUsed] = incfs_fill_block{
.block_index = (uint32_t)blocks[i].pageIndex,
.data_len = blocks[i].dataSize,
.data = (uint64_t)blocks[i].data,
.compression = (uint8_t)blocks[i].compression,
.flags = uint8_t(blocks[i].kind == INCFS_BLOCK_KIND_HASH ? INCFS_BLOCK_FLAGS_HASH
: 0),
};
++incfsBlocksUsed;
}
auto count = writeBlocks(lastBlockFd, incfsBlocks, incfsBlocksUsed);
if (count > 0) {
writtenCount += count;
}
return writtenCount ? writtenCount : count;
}
IncFsErrorCode IncFs_BindMount(const char* sourceDir, const char* targetDir) {
if (!enabled()) {
return -ENOTSUP;
}
if (path::dirName(sourceDir) == path::procfsFdDir) {
// can't find such path in the mount registry, but still can verify the filesystem
// via the stat() call
if (!isIncFsPathImpl(sourceDir)) {
return -EINVAL;
}
} else {
auto [sourceRoot, subpath] = registry().rootAndSubpathFor(sourceDir);
if (sourceRoot.empty()) {
return -EINVAL;
}
if (subpath.empty()) {
LOG(WARNING) << "[incfs] Binding the root mount '" << sourceRoot << "' is not allowed";
return -EINVAL;
}
}
if (auto err = isValidMountTarget(targetDir); err != 0) {
return err;
}
if (::mount(sourceDir, targetDir, nullptr, MS_BIND, nullptr)) {
PLOG(ERROR) << "[incfs] Failed to bind mount '" << sourceDir << "' to '" << targetDir
<< '\'';
return -errno;
}
return 0;
}
IncFsErrorCode IncFs_Unmount(const char* dir) {
if (!enabled()) {
return -ENOTSUP;
}
if (!isIncFsPathImpl(dir)) {
LOG(WARNING) << __func__ << ": umount() called on non-incfs directory '" << dir << '\'';
return -EINVAL;
}
errno = 0;
if (::umount2(dir, MNT_FORCE) == 0 || errno == EINVAL || errno == ENOENT) {
// EINVAL - not a mount point, ENOENT - doesn't exist at all
return -errno;
}
PLOG(WARNING) << __func__ << ": umount(force) failed, detaching '" << dir << '\'';
errno = 0;
if (!::umount2(dir, MNT_DETACH)) {
return 0;
}
PLOG(WARNING) << __func__ << ": umount(detach) returned non-zero for '" << dir << '\'';
return 0;
}
bool IncFs_IsIncFsFd(int fd) {
return isIncFsFdImpl(fd);
}
bool IncFs_IsIncFsPath(const char* path) {
return isIncFsPathImpl(path);
}
IncFsErrorCode IncFs_GetFilledRanges(int fd, IncFsSpan outBuffer, IncFsFilledRanges* filledRanges) {
return IncFs_GetFilledRangesStartingFrom(fd, 0, outBuffer, filledRanges);
}
IncFsErrorCode IncFs_GetFilledRangesStartingFrom(int fd, int startBlockIndex, IncFsSpan outBuffer,
IncFsFilledRanges* filledRanges) {
if (fd < 0) {
return -EBADF;
}
if (startBlockIndex < 0) {
return -EINVAL;
}
if (!outBuffer.data && outBuffer.size > 0) {
return -EINVAL;
}
if (!filledRanges) {
return -EINVAL;
}
// Use this to optimize the incfs call and have the same buffer for both the incfs and the
// public structs.
static_assert(sizeof(IncFsBlockRange) == sizeof(incfs_filled_range));
*filledRanges = {};
auto outStart = (IncFsBlockRange*)outBuffer.data;
auto outEnd = outStart + outBuffer.size / sizeof(*outStart);
auto outPtr = outStart;
int error = 0;
int dataBlocks;
incfs_get_filled_blocks_args args = {};
for (;;) {
auto start = args.index_out ? args.index_out : startBlockIndex;
args = incfs_get_filled_blocks_args{
.range_buffer = (uint64_t)(uintptr_t)outPtr,
.range_buffer_size = uint32_t((outEnd - outPtr) * sizeof(*outPtr)),
.start_index = start,
};
errno = 0;
auto res = ::ioctl(fd, INCFS_IOC_GET_FILLED_BLOCKS, &args);
error = errno;
if (res && error != EINTR && error != ERANGE) {
return -error;
}
dataBlocks = args.data_blocks_out;
outPtr += args.range_buffer_size_out / sizeof(incfs_filled_range);
if (!res || error == ERANGE) {
break;
}
// in case of EINTR we want to continue calling the function
}
if (outPtr > outEnd) {
outPtr = outEnd;
error = ERANGE;
}
filledRanges->endIndex = args.index_out;
auto hashStartPtr = outPtr;
if (outPtr != outStart) {
// figure out the ranges for data block and hash blocks in the output
for (; hashStartPtr != outStart; --hashStartPtr) {
if ((hashStartPtr - 1)->begin < dataBlocks) {
break;
}
}
auto lastDataPtr = hashStartPtr - 1;
// here we go, this is the first block that's before or at the hashes
if (lastDataPtr->end <= dataBlocks) {
; // we're good, the boundary is between the ranges - |hashStartPtr| is correct
} else {
// the hard part: split the |lastDataPtr| range into the data and the hash pieces
if (outPtr == outEnd) {
// the buffer turned out to be too small, even though it actually wasn't
error = ERANGE;
if (hashStartPtr == outEnd) {
// this is even worse: there's no room to put even a single hash block into.
filledRanges->endIndex = lastDataPtr->end = dataBlocks;
} else {
std::copy_backward(lastDataPtr, outPtr - 1, outPtr);
lastDataPtr->end = hashStartPtr->begin = dataBlocks;
filledRanges->endIndex = (outPtr - 1)->end;
}
} else {
std::copy_backward(lastDataPtr, outPtr, outPtr + 1);
lastDataPtr->end = hashStartPtr->begin = dataBlocks;
++outPtr;
}
}
// now fix the indices of all hash blocks - no one should know they're simply past the
// regular data blocks in the file!
for (auto ptr = hashStartPtr; ptr != outPtr; ++ptr) {
ptr->begin -= dataBlocks;
ptr->end -= dataBlocks;
}
}
filledRanges->dataRanges = outStart;
filledRanges->dataRangesCount = hashStartPtr - outStart;
filledRanges->hashRanges = hashStartPtr;
filledRanges->hashRangesCount = outPtr - hashStartPtr;
return -error;
}
static IncFsErrorCode isFullyLoadedV2(std::string_view root, IncFsFileId id) {
if (::access(path::join(root, INCFS_INCOMPLETE_NAME, toStringImpl(id)).c_str(), F_OK)) {
if (errno == ENOENT) {
return 0; // no such incomplete file -> it's fully loaded.
}
return -errno;
}
return -ENODATA;
}
static IncFsErrorCode isFullyLoadedSlow(int fd) {
char buffer[2 * sizeof(IncFsBlockRange)];
IncFsFilledRanges ranges;
auto res = IncFs_GetFilledRanges(fd, IncFsSpan{.data = buffer, .size = std::size(buffer)},
&ranges);
if (res == -ERANGE) {
// need room for more than two ranges - definitely not fully loaded
return -ENODATA;
}
if (res != 0) {
return res;
}
// empty file
if (ranges.endIndex == 0) {
return 0;
}
// file with no hash tree
if (ranges.dataRangesCount == 1 && ranges.hashRangesCount == 0) {
return (ranges.dataRanges[0].begin == 0 && ranges.dataRanges[0].end == ranges.endIndex)
? 0
: -ENODATA;
}
// file with a hash tree
if (ranges.dataRangesCount == 1 && ranges.hashRangesCount == 1) {
// calculate the expected data size from the size of the hash range and |endIndex|, which is
// the total number of blocks in the file, both data and hash blocks together.
if (ranges.hashRanges[0].begin != 0) {
return -ENODATA;
}
const auto expectedDataBlocks =
ranges.endIndex - (ranges.hashRanges[0].end - ranges.hashRanges[0].begin);
return (ranges.dataRanges[0].begin == 0 && ranges.dataRanges[0].end == expectedDataBlocks)
? 0
: -ENODATA;
}
return -ENODATA;
}
IncFsErrorCode IncFs_IsFullyLoaded(int fd) {
if (features() & Features::v2) {
const auto fdPath = path::fromFd(fd);
if (fdPath.empty()) {
return errno ? -errno : -EINVAL;
}
const auto id = getId(::fgetxattr, fd);
if (id == kIncFsInvalidFileId) {
return -errno;
}
return isFullyLoadedV2(registry().rootFor(fdPath), id);
}
return isFullyLoadedSlow(fd);
}
IncFsErrorCode IncFs_IsFullyLoadedByPath(const IncFsControl* control, const char* path) {
if (!control || !path) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
const auto pathRoot = registry().rootFor(path);
if (pathRoot != root) {
return -EINVAL;
}
if (features() & Features::v2) {
const auto id = getId(::getxattr, path);
if (id == kIncFsInvalidFileId) {
return -ENOTSUP;
}
return isFullyLoadedV2(root, id);
}
return isFullyLoadedSlow(openForSpecialOps(control->cmd, makeCommandPath(root, path).c_str()));
}
IncFsErrorCode IncFs_IsFullyLoadedById(const IncFsControl* control, IncFsFileId fileId) {
if (!control) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
if (features() & Features::v2) {
return isFullyLoadedV2(root, fileId);
}
return isFullyLoadedSlow(
openForSpecialOps(control->cmd,
makeCommandPath(root, indexPath(root, fileId)).c_str()));
}
static IncFsErrorCode isEverythingLoadedV2(const IncFsControl* control) {
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto res = forEachFileIn(path::join(root, INCFS_INCOMPLETE_NAME), [](auto) { return false; });
return res < 0 ? res : res > 0 ? -ENODATA : 0;
}
static IncFsErrorCode isEverythingLoadedSlow(const IncFsControl* control) {
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
// No special API for this version of the driver, need to recurse and check each file
// separately. Can at least speed it up by iterating over the .index/ dir and not dealing with
// the directory tree.
const auto indexPath = path::join(root, INCFS_INDEX_NAME);
const auto dir = path::openDir(indexPath.c_str());
if (!dir) {
return -EINVAL;
}
while (const auto entry = ::readdir(dir.get())) {
if (entry->d_type != DT_REG) {
continue;
}
const auto name = path::join(indexPath, entry->d_name);
auto fd =
ab::unique_fd(openForSpecialOps(control->cmd, makeCommandPath(root, name).c_str()));
if (fd.get() < 0) {
PLOG(WARNING) << __func__ << "(): can't open " << entry->d_name << " for special ops";
return fd.release();
}
const auto checkFullyLoaded = IncFs_IsFullyLoaded(fd.get());
if (checkFullyLoaded == 0 || checkFullyLoaded == -EOPNOTSUPP ||
checkFullyLoaded == -ENOTSUP || checkFullyLoaded == -ENOENT) {
// special kinds of files may return an error here, but it still means
// _this_ file is OK - you simply need to check the rest. E.g. can't query
// a mapped file, instead need to check its parent.
continue;
}
return checkFullyLoaded;
}
return 0;
}
IncFsErrorCode IncFs_IsEverythingFullyLoaded(const IncFsControl* control) {
if (!control) {
return -EINVAL;
}
if (features() & Features::v2) {
return isEverythingLoadedV2(control);
}
return isEverythingLoadedSlow(control);
}
IncFsErrorCode IncFs_SetUidReadTimeouts(const IncFsControl* control,
const IncFsUidReadTimeouts timeouts[], size_t count) {
if (!control) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
std::vector<incfs_per_uid_read_timeouts> argTimeouts(count);
for (size_t i = 0; i != count; ++i) {
argTimeouts[i] = incfs_per_uid_read_timeouts{
.uid = (uint32_t)timeouts[i].uid,
.min_time_us = timeouts[i].minTimeUs,
.min_pending_time_us = timeouts[i].minPendingTimeUs,
.max_pending_time_us = timeouts[i].maxPendingTimeUs,
};
}
incfs_set_read_timeouts_args args = {.timeouts_array = (uint64_t)(uintptr_t)argTimeouts.data(),
.timeouts_array_size = uint32_t(
argTimeouts.size() * sizeof(*argTimeouts.data()))};
if (::ioctl(control->cmd, INCFS_IOC_SET_READ_TIMEOUTS, &args)) {
PLOG(WARNING) << "[incfs] setUidReadTimeouts failed";
return -errno;
}
return 0;
}
IncFsErrorCode IncFs_GetUidReadTimeouts(const IncFsControl* control,
IncFsUidReadTimeouts timeouts[], size_t* bufferSize) {
if (!control || !bufferSize) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
std::vector<incfs_per_uid_read_timeouts> argTimeouts(*bufferSize);
incfs_get_read_timeouts_args args = {.timeouts_array = (uint64_t)(uintptr_t)argTimeouts.data(),
.timeouts_array_size = uint32_t(
argTimeouts.size() * sizeof(*argTimeouts.data())),
.timeouts_array_size_out = args.timeouts_array_size};
if (::ioctl(control->cmd, INCFS_IOC_GET_READ_TIMEOUTS, &args)) {
if (errno == E2BIG) {
*bufferSize = args.timeouts_array_size_out / sizeof(*argTimeouts.data());
}
return -errno;
}
*bufferSize = args.timeouts_array_size_out / sizeof(*argTimeouts.data());
for (size_t i = 0; i != *bufferSize; ++i) {
timeouts[i].uid = argTimeouts[i].uid;
timeouts[i].minTimeUs = argTimeouts[i].min_time_us;
timeouts[i].minPendingTimeUs = argTimeouts[i].min_pending_time_us;
timeouts[i].maxPendingTimeUs = argTimeouts[i].max_pending_time_us;
}
return 0;
}
// Trying to detect if this is a mapped file.
// Not the best way as it might return true for other system files.
// TODO: remove after IncFS returns ENOTSUP for such files.
static bool isMapped(int fd) {
char buffer[kIncFsFileIdStringLength];
const auto res = ::fgetxattr(fd, kIdAttrName, buffer, sizeof(buffer));
return res != sizeof(buffer);
}
static IncFsErrorCode getFileBlockCount(int fd, IncFsBlockCounts* blockCount) {
if (isMapped(fd)) {
return -ENOTSUP;
}
incfs_get_block_count_args args = {};
auto res = ::ioctl(fd, INCFS_IOC_GET_BLOCK_COUNT, &args);
if (res < 0) {
return -errno;
}
*blockCount = IncFsBlockCounts{
.totalDataBlocks = args.total_data_blocks_out,
.filledDataBlocks = args.filled_data_blocks_out,
.totalHashBlocks = args.total_hash_blocks_out,
.filledHashBlocks = args.filled_hash_blocks_out,
};
return 0;
}
IncFsErrorCode IncFs_GetFileBlockCountById(const IncFsControl* control, IncFsFileId id,
IncFsBlockCounts* blockCount) {
if (!control) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto name = indexPath(root, id);
auto fd = openRaw(name);
if (fd < 0) {
return fd.get();
}
return getFileBlockCount(fd, blockCount);
}
IncFsErrorCode IncFs_GetFileBlockCountByPath(const IncFsControl* control, const char* path,
IncFsBlockCounts* blockCount) {
if (!control) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
const auto pathRoot = registry().rootFor(path);
const auto root = rootForCmd(control->cmd);
if (root.empty() || root != pathRoot) {
return -EINVAL;
}
auto fd = openRaw(path);
if (fd < 0) {
return fd.get();
}
return getFileBlockCount(fd, blockCount);
}
IncFsErrorCode IncFs_ListIncompleteFiles(const IncFsControl* control, IncFsFileId ids[],
size_t* bufferSize) {
if (!control || !bufferSize) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
size_t index = 0;
int error = 0;
const auto res = forEachFileIn(path::join(root, INCFS_INCOMPLETE_NAME), [&](const char* name) {
if (index >= *bufferSize) {
error = -E2BIG;
} else {
ids[index] = IncFs_FileIdFromString(name);
}
++index;
return true;
});
if (res < 0) {
return res;
}
*bufferSize = index;
return error ? error : 0;
}
IncFsErrorCode IncFs_ForEachFile(const IncFsControl* control, void* context, FileCallback cb) {
if (!control || !cb) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
return forEachFileIn(path::join(root, INCFS_INDEX_NAME), [&](const char* name) {
return cb(context, control, IncFs_FileIdFromString(name));
});
}
IncFsErrorCode IncFs_ForEachIncompleteFile(const IncFsControl* control, void* context,
FileCallback cb) {
if (!control || !cb) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
return forEachFileIn(path::join(root, INCFS_INCOMPLETE_NAME), [&](const char* name) {
return cb(context, control, IncFs_FileIdFromString(name));
});
}
IncFsErrorCode IncFs_WaitForLoadingComplete(const IncFsControl* control, int32_t timeoutMs) {
if (!control) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
using namespace std::chrono;
auto hrTimeout = steady_clock::duration(milliseconds(timeoutMs));
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
ab::unique_fd fd(inotify_init1(IN_NONBLOCK | IN_CLOEXEC));
if (!fd.ok()) {
return -EFAULT;
}
// first create all the watches, and only then list existing files to prevent races
auto dirPath = path::join(root, INCFS_INCOMPLETE_NAME);
int watchFd = inotify_add_watch(fd.get(), dirPath.c_str(), IN_DELETE);
if (watchFd < 0) {
return -errno;
}
size_t count = 0;
auto res = IncFs_ListIncompleteFiles(control, nullptr, &count);
if (!res) {
return 0;
}
if (res != -E2BIG) {
return res;
}
while (hrTimeout > hrTimeout.zero()) {
const auto startTs = steady_clock::now();
pollfd pfd = {fd.get(), POLLIN, 0};
const auto res = ::poll(&pfd, 1, duration_cast<milliseconds>(hrTimeout).count());
if (res == 0) {
return -ETIMEDOUT;
}
if (res < 0) {
const auto error = errno;
if (error != EINTR) {
PLOG(ERROR) << "poll() failed";
return -error;
}
} else {
// empty the inotify fd first to not miss any new deletions,
// then check if the directory is empty.
char buffer[sizeof(inotify_event) + NAME_MAX + 1];
for (;;) {
auto err = TEMP_FAILURE_RETRY(::read(fd.get(), buffer, sizeof(buffer)));
if (err < 0) {
if (errno == EAGAIN) { // no new events
break;
}
return -errno;
}
}
size_t count = 0;
auto res = IncFs_ListIncompleteFiles(control, nullptr, &count);
if (!res) {
return 0;
}
if (res != -E2BIG) {
return res;
}
}
hrTimeout -= steady_clock::now() - startTs;
}
return -ETIMEDOUT;
}
IncFsErrorCode IncFs_WaitForFsWrittenBlocksChange(const IncFsControl* control, int32_t timeoutMs,
IncFsSize* count) {
if (!control || !count) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
using namespace std::chrono;
auto hrTimeout = steady_clock::duration(milliseconds(timeoutMs));
while (hrTimeout > hrTimeout.zero()) {
const auto startTs = steady_clock::now();
pollfd pfd = {control->blocksWritten, POLLIN, 0};
const auto res = ::poll(&pfd, 1, duration_cast<milliseconds>(hrTimeout).count());
if (res > 0) {
break;
}
if (res == 0) {
return -ETIMEDOUT;
}
const auto error = errno;
if (error != EINTR) {
PLOG(ERROR) << "poll() failed";
return -error;
}
hrTimeout -= steady_clock::now() - startTs;
}
char str[32];
auto size = ::read(control->blocksWritten, str, sizeof(str));
if (size < 0) {
const auto error = errno;
PLOG(ERROR) << "read() failed";
return -error;
}
const auto res = std::from_chars(str, str + size, *count);
if (res.ec != std::errc{}) {
return res.ec == std::errc::invalid_argument ? -EINVAL : -ERANGE;
}
return 0;
}
static IncFsErrorCode reserveSpace(const char* backingPath, IncFsSize size) {
auto fd = ab::unique_fd(::open(backingPath, O_WRONLY | O_CLOEXEC));
if (fd < 0) {
return -errno;
}
struct stat st = {};
if (::fstat(fd.get(), &st)) {
return -errno;
}
if (size == kIncFsTrimReservedSpace) {
if (::ftruncate(fd.get(), st.st_size)) {
return -errno;
}
} else {
// Add 1.5% of the size for the hash tree and the blockmap, and some more blocks
// for fixed overhead.
// hash tree is ~33 bytes / page, and blockmap is 10 bytes / page
// no need to round to a page size as filesystems already do that.
const auto backingSize = IncFsSize(size * 1.015) + INCFS_DATA_FILE_BLOCK_SIZE * 4;
if (backingSize < st.st_size) {
return -EPERM;
}
if (::fallocate(fd.get(), FALLOC_FL_KEEP_SIZE, 0, backingSize)) {
return -errno;
}
}
return 0;
}
IncFsErrorCode IncFs_ReserveSpaceByPath(const IncFsControl* control, const char* path,
IncFsSize size) {
if (!control || (size != kIncFsTrimReservedSpace && size < 0)) {
return -EINVAL;
}
const auto [pathRoot, backingRoot, subpath] = registry().detailsFor(path);
const auto root = rootForCmd(control->cmd);
if (root.empty() || root != pathRoot) {
return -EINVAL;
}
return reserveSpace(path::join(backingRoot, subpath).c_str(), size);
}
IncFsErrorCode IncFs_ReserveSpaceById(const IncFsControl* control, IncFsFileId id, IncFsSize size) {
if (!control || (size != kIncFsTrimReservedSpace && size < 0)) {
return -EINVAL;
}
const auto root = rootForCmd(control->cmd);
if (root.empty()) {
return -EINVAL;
}
auto path = indexPath(root, id);
const auto [pathRoot, backingRoot, subpath] = registry().detailsFor(path);
if (root != pathRoot) {
return -EINVAL;
}
return reserveSpace(path::join(backingRoot, subpath).c_str(), size);
}
template <class IntType>
static int readIntFromFile(std::string_view rootDir, std::string_view subPath, IntType& result) {
std::string content;
if (!ab::ReadFileToString(path::join(rootDir, subPath), &content)) {
PLOG(ERROR) << "IncFs_GetMetrics: failed to read file: " << rootDir << "/" << subPath;
return -errno;
}
const auto res = std::from_chars(content.data(), content.data() + content.size(), result);
if (res.ec != std::errc()) {
return -static_cast<int>(res.ec);
}
return 0;
}
IncFsErrorCode IncFs_GetMetrics(const char* sysfsName, IncFsMetrics* metrics) {
if (!sysfsName || !*sysfsName) {
return -EINVAL;
}
const auto kSysfsMetricsDir =
ab::StringPrintf("/sys/fs/%s/instances/%s", INCFS_NAME, sysfsName);
int err;
if (err = readIntFromFile(kSysfsMetricsDir, "reads_delayed_min", metrics->readsDelayedMin);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_delayed_min_us", metrics->readsDelayedMinUs);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_delayed_pending",
metrics->readsDelayedPending);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_delayed_pending_us",
metrics->readsDelayedPendingUs);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_failed_hash_verification",
metrics->readsFailedHashVerification);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_failed_other", metrics->readsFailedOther);
err != 0) {
return err;
}
if (err = readIntFromFile(kSysfsMetricsDir, "reads_failed_timed_out",
metrics->readsFailedTimedOut);
err != 0) {
return err;
}
return 0;
}
IncFsErrorCode IncFs_GetLastReadError(const IncFsControl* control,
IncFsLastReadError* lastReadError) {
if (!control) {
return -EINVAL;
}
if (!(features() & Features::v2)) {
return -ENOTSUP;
}
incfs_get_last_read_error_args args = {};
auto res = ::ioctl(control->cmd, INCFS_IOC_GET_LAST_READ_ERROR, &args);
if (res < 0) {
PLOG(ERROR) << "[incfs] IncFs_GetLastReadError failed.";
return -errno;
}
*lastReadError = IncFsLastReadError{
.timestampUs = args.time_us_out,
.block = static_cast<IncFsBlockIndex>(args.page_out),
.errorNo = args.errno_out,
.uid = static_cast<IncFsUid>(args.uid_out),
};
static_assert(sizeof(args.file_id_out.bytes) == sizeof(lastReadError->id.data));
memcpy(lastReadError->id.data, args.file_id_out.bytes, sizeof(args.file_id_out.bytes));
return 0;
}
MountRegistry& android::incfs::defaultMountRegistry() {
return registry();
}