Merge changes I51628abe,I412d62b7 into rvc-dev

* changes:
  Wrap flock with TEMP_FAILURE_RETRY.
  Try locking after mounting metadata
This commit is contained in:
Yifan Hong 2020-07-08 18:57:30 +00:00 committed by Android (Google) Code Review
commit 82e0c384f3
1 changed files with 15 additions and 3 deletions

View File

@ -1846,7 +1846,7 @@ auto SnapshotManager::OpenFile(const std::string& file, int lock_flags)
PLOG(ERROR) << "Open failed: " << file; PLOG(ERROR) << "Open failed: " << file;
return nullptr; return nullptr;
} }
if (lock_flags != 0 && flock(fd, lock_flags) < 0) { if (lock_flags != 0 && TEMP_FAILURE_RETRY(flock(fd, lock_flags)) < 0) {
PLOG(ERROR) << "Acquire flock failed: " << file; PLOG(ERROR) << "Acquire flock failed: " << file;
return nullptr; return nullptr;
} }
@ -1857,7 +1857,7 @@ auto SnapshotManager::OpenFile(const std::string& file, int lock_flags)
} }
SnapshotManager::LockedFile::~LockedFile() { SnapshotManager::LockedFile::~LockedFile() {
if (flock(fd_, LOCK_UN) < 0) { if (TEMP_FAILURE_RETRY(flock(fd_, LOCK_UN)) < 0) {
PLOG(ERROR) << "Failed to unlock file: " << path_; PLOG(ERROR) << "Failed to unlock file: " << path_;
} }
} }
@ -2516,7 +2516,19 @@ std::unique_ptr<AutoDevice> SnapshotManager::EnsureMetadataMounted() {
LOG(INFO) << "EnsureMetadataMounted does nothing in Android mode."; LOG(INFO) << "EnsureMetadataMounted does nothing in Android mode.";
return std::unique_ptr<AutoUnmountDevice>(new AutoUnmountDevice()); return std::unique_ptr<AutoUnmountDevice>(new AutoUnmountDevice());
} }
return AutoUnmountDevice::New(device_->GetMetadataDir()); auto ret = AutoUnmountDevice::New(device_->GetMetadataDir());
if (ret == nullptr) return nullptr;
// In rescue mode, it is possible to erase and format metadata, but /metadata/ota is not
// created to execute snapshot updates. Hence, subsequent calls is likely to fail because
// Lock*() fails. By failing early and returning nullptr here, update_engine_sideload can
// treat this case as if /metadata is not mounted.
if (!LockShared()) {
LOG(WARNING) << "/metadata is mounted, but errors occur when acquiring a shared lock. "
"Subsequent calls to SnapshotManager will fail. Unmounting /metadata now.";
return nullptr;
}
return ret;
} }
bool SnapshotManager::HandleImminentDataWipe(const std::function<void()>& callback) { bool SnapshotManager::HandleImminentDataWipe(const std::function<void()>& callback) {