mozilla
/
gecko-dev
зеркало из https://github.com/mozilla/gecko-dev.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
gecko-dev/dom/asmjscache/AsmJSCache.cpp

1815 строки
53 KiB
C++
Исходник Ответственный История

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "AsmJSCache.h"
#include <stdio.h>
#include "js/RootingAPI.h"
#include "jsfriendapi.h"
#include "mozilla/Assertions.h"
#include "mozilla/CondVar.h"
#include "mozilla/CycleCollectedJSRuntime.h"
#include "mozilla/dom/asmjscache/PAsmJSCacheEntryChild.h"
#include "mozilla/dom/asmjscache/PAsmJSCacheEntryParent.h"
#include "mozilla/dom/PermissionMessageUtils.h"
#include "mozilla/dom/quota/Client.h"
#include "mozilla/dom/quota/QuotaManager.h"
#include "mozilla/dom/quota/QuotaObject.h"
#include "mozilla/dom/quota/UsageInfo.h"
#include "mozilla/HashFunctions.h"
#include "mozilla/ipc/BackgroundChild.h"
#include "mozilla/ipc/BackgroundParent.h"
#include "mozilla/ipc/BackgroundUtils.h"
#include "mozilla/ipc/PBackgroundChild.h"
#include "mozilla/Unused.h"
#include "nsAutoPtr.h"
#include "nsAtom.h"
#include "nsIFile.h"
#include "nsIPrincipal.h"
#include "nsIRunnable.h"
#include "nsISimpleEnumerator.h"
#include "nsIThread.h"
#include "nsJSPrincipals.h"
#include "nsThreadUtils.h"
#include "nsXULAppAPI.h"
#include "prio.h"
#include "private/pprio.h"
#define ASMJSCACHE_METADATA_FILE_NAME "metadata"
#define ASMJSCACHE_ENTRY_FILE_NAME_BASE "module"
using mozilla::HashString;
using mozilla::Unused;
using mozilla::dom::quota::AssertIsOnIOThread;
using mozilla::dom::quota::DirectoryLock;
using mozilla::dom::quota::PersistenceType;
using mozilla::dom::quota::QuotaManager;
using mozilla::dom::quota::QuotaObject;
using mozilla::dom::quota::UsageInfo;
using mozilla::ipc::AssertIsOnBackgroundThread;
using mozilla::ipc::BackgroundChild;
using mozilla::ipc::IsOnBackgroundThread;
using mozilla::ipc::PBackgroundChild;
using mozilla::ipc::PrincipalInfo;
namespace mozilla {
MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLATE(ScopedPRFileDesc, PRFileDesc,
PR_Close);
namespace dom {
namespace asmjscache {
namespace {
class ParentRunnable;
// Anything smaller should compile fast enough that caching will just add
// overhead.
static const size_t sMinCachedModuleLength = 10000;
// The number of characters to hash into the Metadata::Entry::mFastHash.
static const unsigned sNumFastHashChars = 4096;
// Track all live parent actors.
typedef nsTArray<const ParentRunnable*> ParentActorArray;
StaticAutoPtr<ParentActorArray> sLiveParentActors;
nsresult WriteMetadataFile(nsIFile* aMetadataFile, const Metadata& aMetadata) {
int32_t openFlags = PR_WRONLY | PR_TRUNCATE | PR_CREATE_FILE;
JS::BuildIdCharVector buildId;
bool ok = GetBuildId(&buildId);
NS_ENSURE_TRUE(ok, NS_ERROR_OUT_OF_MEMORY);
ScopedPRFileDesc fd;
nsresult rv = aMetadataFile->OpenNSPRFileDesc(openFlags, 0644, &fd.rwget());
NS_ENSURE_SUCCESS(rv, rv);
uint32_t length = buildId.length();
int32_t bytesWritten = PR_Write(fd, &length, sizeof(length));
NS_ENSURE_TRUE(bytesWritten == sizeof(length), NS_ERROR_UNEXPECTED);
bytesWritten = PR_Write(fd, buildId.begin(), length);
NS_ENSURE_TRUE(bytesWritten == int32_t(length), NS_ERROR_UNEXPECTED);
bytesWritten = PR_Write(fd, &aMetadata, sizeof(aMetadata));
NS_ENSURE_TRUE(bytesWritten == sizeof(aMetadata), NS_ERROR_UNEXPECTED);
return NS_OK;
}
nsresult ReadMetadataFile(nsIFile* aMetadataFile, Metadata& aMetadata) {
int32_t openFlags = PR_RDONLY;
ScopedPRFileDesc fd;
nsresult rv = aMetadataFile->OpenNSPRFileDesc(openFlags, 0644, &fd.rwget());
NS_ENSURE_SUCCESS(rv, rv);
// Read the buildid and check that it matches the current buildid
JS::BuildIdCharVector currentBuildId;
bool ok = GetBuildId(&currentBuildId);
NS_ENSURE_TRUE(ok, NS_ERROR_OUT_OF_MEMORY);
uint32_t length;
int32_t bytesRead = PR_Read(fd, &length, sizeof(length));
NS_ENSURE_TRUE(bytesRead == sizeof(length), NS_ERROR_UNEXPECTED);
NS_ENSURE_TRUE(currentBuildId.length() == length, NS_ERROR_UNEXPECTED);
JS::BuildIdCharVector fileBuildId;
ok = fileBuildId.resize(length);
NS_ENSURE_TRUE(ok, NS_ERROR_OUT_OF_MEMORY);
bytesRead = PR_Read(fd, fileBuildId.begin(), length);
NS_ENSURE_TRUE(bytesRead == int32_t(length), NS_ERROR_UNEXPECTED);
for (uint32_t i = 0; i < length; i++) {
if (currentBuildId[i] != fileBuildId[i]) {
return NS_ERROR_FAILURE;
}
}
// Read the Metadata struct
bytesRead = PR_Read(fd, &aMetadata, sizeof(aMetadata));
NS_ENSURE_TRUE(bytesRead == sizeof(aMetadata), NS_ERROR_UNEXPECTED);
return NS_OK;
}
nsresult GetCacheFile(nsIFile* aDirectory, unsigned aModuleIndex,
nsIFile** aCacheFile) {
nsCOMPtr<nsIFile> cacheFile;
nsresult rv = aDirectory->Clone(getter_AddRefs(cacheFile));
NS_ENSURE_SUCCESS(rv, rv);
nsString cacheFileName = NS_LITERAL_STRING(ASMJSCACHE_ENTRY_FILE_NAME_BASE);
cacheFileName.AppendInt(aModuleIndex);
rv = cacheFile->Append(cacheFileName);
NS_ENSURE_SUCCESS(rv, rv);
cacheFile.forget(aCacheFile);
return NS_OK;
}
class AutoDecreaseUsageForOrigin {
const nsACString& mGroup;
const nsACString& mOrigin;
public:
uint64_t mFreed;
AutoDecreaseUsageForOrigin(const nsACString& aGroup,
const nsACString& aOrigin)
: mGroup(aGroup), mOrigin(aOrigin), mFreed(0) {}
~AutoDecreaseUsageForOrigin() {
AssertIsOnIOThread();
if (!mFreed) {
return;
}
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm, "We are on the QuotaManager's IO thread");
qm->DecreaseUsageForOrigin(quota::PERSISTENCE_TYPE_TEMPORARY, mGroup,
mOrigin, mFreed);
}
};
static void EvictEntries(nsIFile* aDirectory, const nsACString& aGroup,
const nsACString& aOrigin, uint64_t aNumBytes,
Metadata& aMetadata) {
AssertIsOnIOThread();
AutoDecreaseUsageForOrigin usage(aGroup, aOrigin);
for (int i = Metadata::kLastEntry; i >= 0 && usage.mFreed < aNumBytes; i--) {
Metadata::Entry& entry = aMetadata.mEntries[i];
unsigned moduleIndex = entry.mModuleIndex;
nsCOMPtr<nsIFile> file;
nsresult rv = GetCacheFile(aDirectory, moduleIndex, getter_AddRefs(file));
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
bool exists;
rv = file->Exists(&exists);
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
if (exists) {
int64_t fileSize;
rv = file->GetFileSize(&fileSize);
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
rv = file->Remove(false);
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
usage.mFreed += fileSize;
}
entry.clear();
}
}
/*******************************************************************************
* Client
******************************************************************************/
class Client : public quota::Client {
static Client* sInstance;
bool mShutdownRequested;
public:
Client();
static bool IsShuttingDownOnBackgroundThread() {
AssertIsOnBackgroundThread();
if (sInstance) {
return sInstance->IsShuttingDown();
}
return QuotaManager::IsShuttingDown();
}
static bool IsShuttingDownOnNonBackgroundThread() {
MOZ_ASSERT(!IsOnBackgroundThread());
return QuotaManager::IsShuttingDown();
}
bool IsShuttingDown() const {
AssertIsOnBackgroundThread();
return mShutdownRequested;
}
NS_INLINE_DECL_REFCOUNTING(Client, override)
Type GetType() override;
nsresult InitOrigin(PersistenceType aPersistenceType,
const nsACString& aGroup, const nsACString& aOrigin,
const AtomicBool& aCanceled,
UsageInfo* aUsageInfo) override;
nsresult GetUsageForOrigin(PersistenceType aPersistenceType,
const nsACString& aGroup,
const nsACString& aOrigin,
const AtomicBool& aCanceled,
UsageInfo* aUsageInfo) override;
void OnOriginClearCompleted(PersistenceType aPersistenceType,
const nsACString& aOrigin) override;
void ReleaseIOThreadObjects() override;
void AbortOperations(const nsACString& aOrigin) override;
void AbortOperationsForProcess(ContentParentId aContentParentId) override;
void StartIdleMaintenance() override;
void StopIdleMaintenance() override;
void ShutdownWorkThreads() override;
private:
~Client() override;
};
// FileDescriptorHolder owns a file descriptor and its memory mapping.
// FileDescriptorHolder is derived by two runnable classes (that is,
// (Parent|Child)Runnable.
class FileDescriptorHolder : public Runnable {
public:
FileDescriptorHolder()
: Runnable("dom::asmjscache::FileDescriptorHolder"),
mQuotaObject(nullptr),
mFileSize(INT64_MIN),
mFileDesc(nullptr),
mFileMap(nullptr),
mMappedMemory(nullptr) {}
~FileDescriptorHolder() override {
// These resources should have already been released by Finish().
MOZ_ASSERT(!mQuotaObject);
MOZ_ASSERT(!mMappedMemory);
MOZ_ASSERT(!mFileMap);
MOZ_ASSERT(!mFileDesc);
}
size_t FileSize() const {
MOZ_ASSERT(mFileSize >= 0, "Accessing FileSize of unopened file");
return mFileSize;
}
PRFileDesc* FileDesc() const {
MOZ_ASSERT(mFileDesc, "Accessing FileDesc of unopened file");
return mFileDesc;
}
bool MapMemory(OpenMode aOpenMode) {
MOZ_ASSERT(!mFileMap, "Cannot call MapMemory twice");
PRFileMapProtect mapFlags =
aOpenMode == eOpenForRead ? PR_PROT_READONLY : PR_PROT_READWRITE;
mFileMap = PR_CreateFileMap(mFileDesc, mFileSize, mapFlags);
NS_ENSURE_TRUE(mFileMap, false);
mMappedMemory = PR_MemMap(mFileMap, 0, mFileSize);
NS_ENSURE_TRUE(mMappedMemory, false);
return true;
}
void* MappedMemory() const {
MOZ_ASSERT(mMappedMemory, "Accessing MappedMemory of un-mapped file");
return mMappedMemory;
}
protected:
// This method must be called before the directory lock is released (the lock
// is protecting these resources). It is idempotent, so it is ok to call
// multiple times (or before the file has been fully opened).
void Finish() {
if (mMappedMemory) {
PR_MemUnmap(mMappedMemory, mFileSize);
mMappedMemory = nullptr;
}
if (mFileMap) {
PR_CloseFileMap(mFileMap);
mFileMap = nullptr;
}
if (mFileDesc) {
PR_Close(mFileDesc);
mFileDesc = nullptr;
}
// Holding the QuotaObject alive until all the cache files are closed
// enables assertions in QuotaManager that the cache entry isn't cleared
// while we are working on it.
mQuotaObject = nullptr;
}
RefPtr<QuotaObject> mQuotaObject;
int64_t mFileSize;
PRFileDesc* mFileDesc;
PRFileMap* mFileMap;
void* mMappedMemory;
};
// A runnable that implements a state machine required to open a cache entry.
// It executes in the parent for a cache access originating in the child.
// This runnable gets registered as an IPDL subprotocol actor so that it
// can communicate with the corresponding ChildRunnable.
class ParentRunnable final : public FileDescriptorHolder,
public quota::OpenDirectoryListener,
public PAsmJSCacheEntryParent {
public:
// We need to always declare refcounting because
// OpenDirectoryListener has pure-virtual refcounting.
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSIRUNNABLE
ParentRunnable(const PrincipalInfo& aPrincipalInfo, OpenMode aOpenMode,
const WriteParams& aWriteParams)
: mOwningEventTarget(GetCurrentThreadEventTarget()),
mPrincipalInfo(aPrincipalInfo),
mOpenMode(aOpenMode),
mWriteParams(aWriteParams),
mOperationMayProceed(true),
mModuleIndex(0),
mState(eInitial),
mResult(JS::AsmJSCache_InternalError),
mActorDestroyed(false),
mOpened(false) {
MOZ_ASSERT(XRE_IsParentProcess());
AssertIsOnOwningThread();
}
private:
~ParentRunnable() override {
MOZ_ASSERT(mState == eFinished);
MOZ_ASSERT(!mDirectoryLock);
MOZ_ASSERT(mActorDestroyed);
}
#ifdef DEBUG
bool IsOnOwningThread() const {
MOZ_ASSERT(mOwningEventTarget);
bool current;
return NS_SUCCEEDED(mOwningEventTarget->IsOnCurrentThread(&current)) &&
current;
}
#endif
void AssertIsOnOwningThread() const {
MOZ_ASSERT(IsOnBackgroundThread());
MOZ_ASSERT(IsOnOwningThread());
}
void AssertIsOnNonOwningThread() const {
MOZ_ASSERT(!IsOnBackgroundThread());
MOZ_ASSERT(!IsOnOwningThread());
}
bool IsActorDestroyed() const {
AssertIsOnOwningThread();
return mActorDestroyed;
}
// May be called on any thread, but you should call IsActorDestroyed() if
// you know you're on the background thread because it is slightly faster.
bool OperationMayProceed() const { return mOperationMayProceed; }
// This method is called on the owning thread when the JS engine is finished
// reading/writing the cache entry.
void Close() {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eOpened);
MOZ_ASSERT(mResult == JS::AsmJSCache_Success);
mState = eFinished;
MOZ_ASSERT(mOpened);
mOpened = false;
FinishOnOwningThread();
if (!mActorDestroyed) {
Unused << Send__delete__(this, mResult);
}
}
// This method is called upon any failure that prevents the eventual opening
// of the cache entry.
void Fail() {
AssertIsOnOwningThread();
MOZ_ASSERT(mState != eFinished);
MOZ_ASSERT(mResult != JS::AsmJSCache_Success);
mState = eFinished;
MOZ_ASSERT(!mOpened);
FinishOnOwningThread();
if (!mActorDestroyed) {
Unused << Send__delete__(this, mResult);
}
}
// The same as method above but is intended to be called off the owning
// thread.
void FailOnNonOwningThread() {
AssertIsOnNonOwningThread();
MOZ_ASSERT(mState != eOpened && mState != eFailing && mState != eFinished);
mState = eFailing;
MOZ_ALWAYS_SUCCEEDS(mOwningEventTarget->Dispatch(this, NS_DISPATCH_NORMAL));
}
nsresult InitOnMainThread();
void OpenDirectory();
nsresult ReadMetadata();
nsresult OpenCacheFileForWrite();
nsresult OpenCacheFileForRead();
void FinishOnOwningThread();
void DispatchToIOThread() {
AssertIsOnOwningThread();
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread()) ||
IsActorDestroyed()) {
Fail();
return;
}
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm);
nsresult rv = qm->IOThread()->Dispatch(this, NS_DISPATCH_NORMAL);
if (NS_FAILED(rv)) {
Fail();
return;
}
}
// OpenDirectoryListener overrides.
void DirectoryLockAcquired(DirectoryLock* aLock) override;
void DirectoryLockFailed() override;
// IPDL methods.
void ActorDestroy(ActorDestroyReason why) override {
AssertIsOnOwningThread();
MOZ_ASSERT(!mActorDestroyed);
MOZ_ASSERT(mOperationMayProceed);
mActorDestroyed = true;
mOperationMayProceed = false;
// Assume ActorDestroy can happen at any time, so we can't probe the
// current state since mState can be modified on any thread (only one
// thread at a time based on the state machine).
// However we can use mOpened which is only touched on the owning thread.
// If mOpened is true, we can also modify mState since we are guaranteed
// that there are no pending runnables which would probe mState to decide
// what code needs to run (there shouldn't be any running runnables on
// other threads either).
if (mOpened) {
Close();
MOZ_ASSERT(mState == eFinished);
}
// We don't have to call Fail() if mOpened is not true since it means that
// either nothing has been initialized yet, so nothing to cleanup or there
// are pending runnables that will detect that the actor has been destroyed
// and call Fail().
}
mozilla::ipc::IPCResult RecvSelectCacheFileToRead(
const OpenMetadataForReadResponse& aResponse) override {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eWaitingToOpenCacheFileForRead);
MOZ_ASSERT(mOpenMode == eOpenForRead);
MOZ_ASSERT(!mOpened);
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread())) {
Fail();
return IPC_OK();
}
switch (aResponse.type()) {
case OpenMetadataForReadResponse::TAsmJSCacheResult: {
MOZ_ASSERT(aResponse.get_AsmJSCacheResult() != JS::AsmJSCache_Success);
mResult = aResponse.get_AsmJSCacheResult();
// This ParentRunnable can only be held alive by the IPDL. Fail()
// clears that last reference. So we need to add a self reference here.
RefPtr<ParentRunnable> kungFuDeathGrip = this;
Fail();
break;
}
case OpenMetadataForReadResponse::Tuint32_t:
// A cache entry has been selected to open.
mModuleIndex = aResponse.get_uint32_t();
mState = eReadyToOpenCacheFileForRead;
DispatchToIOThread();
break;
default:
MOZ_CRASH("Should never get here!");
}
return IPC_OK();
}
mozilla::ipc::IPCResult RecvClose() override {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eOpened);
// This ParentRunnable can only be held alive by the IPDL. Close() clears
// that last reference. So we need to add a self reference here.
RefPtr<ParentRunnable> kungFuDeathGrip = this;
Close();
MOZ_ASSERT(mState == eFinished);
return IPC_OK();
}
nsCOMPtr<nsIEventTarget> mOwningEventTarget;
const PrincipalInfo mPrincipalInfo;
const OpenMode mOpenMode;
const WriteParams mWriteParams;
// State initialized during eInitial:
nsCString mSuffix;
nsCString mGroup;
nsCString mOrigin;
RefPtr<DirectoryLock> mDirectoryLock;
// State initialized during eReadyToReadMetadata
nsCOMPtr<nsIFile> mDirectory;
nsCOMPtr<nsIFile> mMetadataFile;
Metadata mMetadata;
Atomic<bool> mOperationMayProceed;
// State initialized during eWaitingToOpenCacheFileForRead
unsigned mModuleIndex;
enum State {
eInitial, // Just created, waiting to be dispatched to main thread
eWaitingToFinishInit, // Waiting to finish initialization
eWaitingToOpenDirectory, // Waiting to open directory
eWaitingToOpenMetadata, // Waiting to be called back from OpenDirectory
eReadyToReadMetadata, // Waiting to read the metadata file on the IO thread
eSendingMetadataForRead, // Waiting to send OnOpenMetadataForRead
eWaitingToOpenCacheFileForRead, // Waiting to hear back from child
eReadyToOpenCacheFileForRead, // Waiting to open cache file for read
eSendingCacheFile, // Waiting to send OnOpenCacheFile on the owning thread
eOpened, // Finished calling OnOpenCacheFile, waiting to be closed
eFailing, // Just failed, waiting to be dispatched to the owning thread
eFinished, // Terminal state
};
State mState;
JS::AsmJSCacheResult mResult;
bool mActorDestroyed;
bool mOpened;
};
nsresult ParentRunnable::InitOnMainThread() {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mState == eInitial);
MOZ_ASSERT(mPrincipalInfo.type() != PrincipalInfo::TNullPrincipalInfo);
nsresult rv;
nsCOMPtr<nsIPrincipal> principal =
PrincipalInfoToPrincipal(mPrincipalInfo, &rv);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
rv = QuotaManager::GetInfoFromPrincipal(principal, &mSuffix, &mGroup,
&mOrigin);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
void ParentRunnable::OpenDirectory() {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eWaitingToFinishInit ||
mState == eWaitingToOpenDirectory);
MOZ_ASSERT(QuotaManager::Get());
mState = eWaitingToOpenMetadata;
// XXX The exclusive lock shouldn't be needed for read operations.
QuotaManager::Get()->OpenDirectory(quota::PERSISTENCE_TYPE_TEMPORARY, mGroup,
mOrigin, quota::Client::ASMJS,
/* aExclusive */ true, this);
}
nsresult ParentRunnable::ReadMetadata() {
AssertIsOnIOThread();
MOZ_ASSERT(mState == eReadyToReadMetadata);
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm, "We are on the QuotaManager's IO thread");
nsresult rv = qm->EnsureOriginIsInitialized(
quota::PERSISTENCE_TYPE_TEMPORARY, mSuffix, mGroup, mOrigin,
/* aCreateIfNotExists */ true, getter_AddRefs(mDirectory));
if (NS_WARN_IF(NS_FAILED(rv))) {
mResult = JS::AsmJSCache_StorageInitFailure;
return rv;
}
rv = mDirectory->Append(NS_LITERAL_STRING(ASMJSCACHE_DIRECTORY_NAME));
NS_ENSURE_SUCCESS(rv, rv);
bool exists;
rv = mDirectory->Exists(&exists);
NS_ENSURE_SUCCESS(rv, rv);
if (!exists) {
rv = mDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
NS_ENSURE_SUCCESS(rv, rv);
} else {
DebugOnly<bool> isDirectory;
MOZ_ASSERT(NS_SUCCEEDED(mDirectory->IsDirectory(&isDirectory)));
MOZ_ASSERT(isDirectory, "Should have caught this earlier!");
}
rv = mDirectory->Clone(getter_AddRefs(mMetadataFile));
NS_ENSURE_SUCCESS(rv, rv);
rv = mMetadataFile->Append(NS_LITERAL_STRING(ASMJSCACHE_METADATA_FILE_NAME));
NS_ENSURE_SUCCESS(rv, rv);
rv = mMetadataFile->Exists(&exists);
NS_ENSURE_SUCCESS(rv, rv);
if (exists && NS_FAILED(ReadMetadataFile(mMetadataFile, mMetadata))) {
exists = false;
}
if (!exists) {
// If we are reading, we can't possibly have a cache hit.
if (mOpenMode == eOpenForRead) {
return NS_ERROR_FILE_NOT_FOUND;
}
// Initialize Metadata with a valid empty state for the LRU cache.
for (unsigned i = 0; i < Metadata::kNumEntries; i++) {
Metadata::Entry& entry = mMetadata.mEntries[i];
entry.mModuleIndex = i;
entry.clear();
}
}
return NS_OK;
}
nsresult ParentRunnable::OpenCacheFileForWrite() {
AssertIsOnIOThread();
MOZ_ASSERT(mState == eReadyToReadMetadata);
MOZ_ASSERT(mOpenMode == eOpenForWrite);
mFileSize = mWriteParams.mSize;
// Kick out the oldest entry in the LRU queue in the metadata.
mModuleIndex = mMetadata.mEntries[Metadata::kLastEntry].mModuleIndex;
nsCOMPtr<nsIFile> file;
nsresult rv = GetCacheFile(mDirectory, mModuleIndex, getter_AddRefs(file));
NS_ENSURE_SUCCESS(rv, rv);
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm, "We are on the QuotaManager's IO thread");
// Create the QuotaObject before all file IO and keep it alive until caching
// completes to get maximum assertion coverage in QuotaManager against
// concurrent removal, etc.
mQuotaObject = qm->GetQuotaObject(quota::PERSISTENCE_TYPE_TEMPORARY, mGroup,
mOrigin, file);
NS_ENSURE_STATE(mQuotaObject);
if (!mQuotaObject->MaybeUpdateSize(mWriteParams.mSize,
/* aTruncate */ false)) {
// If the request fails, it might be because mOrigin is using too much
// space (MaybeUpdateSize will not evict our own origin since it is
// active). Try to make some space by evicting LRU entries until there is
// enough space.
EvictEntries(mDirectory, mGroup, mOrigin, mWriteParams.mSize, mMetadata);
if (!mQuotaObject->MaybeUpdateSize(mWriteParams.mSize,
/* aTruncate */ false)) {
mResult = JS::AsmJSCache_QuotaExceeded;
return NS_ERROR_FAILURE;
}
}
int32_t openFlags = PR_RDWR | PR_TRUNCATE | PR_CREATE_FILE;
rv = file->OpenNSPRFileDesc(openFlags, 0644, &mFileDesc);
NS_ENSURE_SUCCESS(rv, rv);
// Move the mModuleIndex's LRU entry to the recent end of the queue.
PodMove(mMetadata.mEntries + 1, mMetadata.mEntries, Metadata::kLastEntry);
Metadata::Entry& entry = mMetadata.mEntries[0];
entry.mFastHash = mWriteParams.mFastHash;
entry.mNumChars = mWriteParams.mNumChars;
entry.mFullHash = mWriteParams.mFullHash;
entry.mModuleIndex = mModuleIndex;
rv = WriteMetadataFile(mMetadataFile, mMetadata);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult ParentRunnable::OpenCacheFileForRead() {
AssertIsOnIOThread();
MOZ_ASSERT(mState == eReadyToOpenCacheFileForRead);
MOZ_ASSERT(mOpenMode == eOpenForRead);
nsCOMPtr<nsIFile> file;
nsresult rv = GetCacheFile(mDirectory, mModuleIndex, getter_AddRefs(file));
NS_ENSURE_SUCCESS(rv, rv);
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm, "We are on the QuotaManager's IO thread");
// Even though it's not strictly necessary, create the QuotaObject before all
// file IO and keep it alive until caching completes to get maximum assertion
// coverage in QuotaManager against concurrent removal, etc.
mQuotaObject = qm->GetQuotaObject(quota::PERSISTENCE_TYPE_TEMPORARY, mGroup,
mOrigin, file);
NS_ENSURE_STATE(mQuotaObject);
rv = file->GetFileSize(&mFileSize);
NS_ENSURE_SUCCESS(rv, rv);
int32_t openFlags = PR_RDONLY | nsIFile::OS_READAHEAD;
rv = file->OpenNSPRFileDesc(openFlags, 0644, &mFileDesc);
NS_ENSURE_SUCCESS(rv, rv);
// Move the mModuleIndex's LRU entry to the recent end of the queue.
unsigned lruIndex = 0;
while (mMetadata.mEntries[lruIndex].mModuleIndex != mModuleIndex) {
if (++lruIndex == Metadata::kNumEntries) {
return NS_ERROR_UNEXPECTED;
}
}
Metadata::Entry entry = mMetadata.mEntries[lruIndex];
PodMove(mMetadata.mEntries + 1, mMetadata.mEntries, lruIndex);
mMetadata.mEntries[0] = entry;
rv = WriteMetadataFile(mMetadataFile, mMetadata);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
void ParentRunnable::FinishOnOwningThread() {
AssertIsOnOwningThread();
// Per FileDescriptorHolder::Finish()'s comment, call before
// releasing the directory lock.
FileDescriptorHolder::Finish();
mDirectoryLock = nullptr;
MOZ_ASSERT(sLiveParentActors);
sLiveParentActors->RemoveElement(this);
if (sLiveParentActors->IsEmpty()) {
sLiveParentActors = nullptr;
}
}
NS_IMETHODIMP
ParentRunnable::Run() {
nsresult rv;
// All success/failure paths must eventually call Finish() to avoid leaving
// the parser hanging.
switch (mState) {
case eInitial: {
MOZ_ASSERT(NS_IsMainThread());
if (NS_WARN_IF(Client::IsShuttingDownOnNonBackgroundThread()) ||
!OperationMayProceed()) {
FailOnNonOwningThread();
return NS_OK;
}
rv = InitOnMainThread();
if (NS_FAILED(rv)) {
FailOnNonOwningThread();
return NS_OK;
}
mState = eWaitingToFinishInit;
MOZ_ALWAYS_SUCCEEDS(
mOwningEventTarget->Dispatch(this, NS_DISPATCH_NORMAL));
return NS_OK;
}
case eWaitingToFinishInit: {
AssertIsOnOwningThread();
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread()) ||
IsActorDestroyed()) {
Fail();
return NS_OK;
}
if (QuotaManager::Get()) {
OpenDirectory();
return NS_OK;
}
mState = eWaitingToOpenDirectory;
QuotaManager::GetOrCreate(this);
return NS_OK;
}
case eWaitingToOpenDirectory: {
AssertIsOnOwningThread();
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread()) ||
IsActorDestroyed()) {
Fail();
return NS_OK;
}
if (NS_WARN_IF(!QuotaManager::Get())) {
Fail();
return NS_OK;
}
OpenDirectory();
return NS_OK;
}
case eReadyToReadMetadata: {
AssertIsOnIOThread();
if (NS_WARN_IF(Client::IsShuttingDownOnNonBackgroundThread()) ||
!OperationMayProceed()) {
FailOnNonOwningThread();
return NS_OK;
}
rv = ReadMetadata();
if (NS_FAILED(rv)) {
FailOnNonOwningThread();
return NS_OK;
}
if (mOpenMode == eOpenForRead) {
mState = eSendingMetadataForRead;
MOZ_ALWAYS_SUCCEEDS(
mOwningEventTarget->Dispatch(this, NS_DISPATCH_NORMAL));
return NS_OK;
}
rv = OpenCacheFileForWrite();
if (NS_FAILED(rv)) {
FailOnNonOwningThread();
return NS_OK;
}
mState = eSendingCacheFile;
MOZ_ALWAYS_SUCCEEDS(
mOwningEventTarget->Dispatch(this, NS_DISPATCH_NORMAL));
return NS_OK;
}
case eSendingMetadataForRead: {
AssertIsOnOwningThread();
MOZ_ASSERT(mOpenMode == eOpenForRead);
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread()) ||
IsActorDestroyed()) {
Fail();
return NS_OK;
}
mState = eWaitingToOpenCacheFileForRead;
// Metadata is now open.
if (!SendOnOpenMetadataForRead(mMetadata)) {
Fail();
return NS_OK;
}
return NS_OK;
}
case eReadyToOpenCacheFileForRead: {
AssertIsOnIOThread();
MOZ_ASSERT(mOpenMode == eOpenForRead);
if (NS_WARN_IF(Client::IsShuttingDownOnNonBackgroundThread()) ||
!OperationMayProceed()) {
FailOnNonOwningThread();
return NS_OK;
}
rv = OpenCacheFileForRead();
if (NS_FAILED(rv)) {
FailOnNonOwningThread();
return NS_OK;
}
mState = eSendingCacheFile;
MOZ_ALWAYS_SUCCEEDS(
mOwningEventTarget->Dispatch(this, NS_DISPATCH_NORMAL));
return NS_OK;
}
case eSendingCacheFile: {
AssertIsOnOwningThread();
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread()) ||
IsActorDestroyed()) {
Fail();
return NS_OK;
}
mState = eOpened;
FileDescriptor::PlatformHandleType handle =
FileDescriptor::PlatformHandleType(
PR_FileDesc2NativeHandle(mFileDesc));
if (!SendOnOpenCacheFile(mFileSize, FileDescriptor(handle))) {
Fail();
return NS_OK;
}
// The entry is now open.
MOZ_ASSERT(!mOpened);
mOpened = true;
mResult = JS::AsmJSCache_Success;
return NS_OK;
}
case eFailing: {
AssertIsOnOwningThread();
Fail();
return NS_OK;
}
case eWaitingToOpenMetadata:
case eWaitingToOpenCacheFileForRead:
case eOpened:
case eFinished: {
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Shouldn't Run() in this state");
}
}
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Corrupt state");
return NS_OK;
}
void ParentRunnable::DirectoryLockAcquired(DirectoryLock* aLock) {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eWaitingToOpenMetadata);
MOZ_ASSERT(!mDirectoryLock);
mDirectoryLock = aLock;
mState = eReadyToReadMetadata;
DispatchToIOThread();
}
void ParentRunnable::DirectoryLockFailed() {
AssertIsOnOwningThread();
MOZ_ASSERT(mState == eWaitingToOpenMetadata);
MOZ_ASSERT(!mDirectoryLock);
Fail();
}
NS_IMPL_ISUPPORTS_INHERITED0(ParentRunnable, FileDescriptorHolder)
bool FindHashMatch(const Metadata& aMetadata, const ReadParams& aReadParams,
unsigned* aModuleIndex) {
// Perform a fast hash of the first sNumFastHashChars chars. Each cache entry
// also stores an mFastHash of its first sNumFastHashChars so this gives us a
// fast way to probabilistically determine whether we have a cache hit. We
// still do a full hash of all the chars before returning the cache file to
// the engine to avoid penalizing the case where there are multiple cached
// asm.js modules where the first sNumFastHashChars are the same. The
// mFullHash of each cache entry can have a different mNumChars so the fast
// hash allows us to avoid performing up to Metadata::kNumEntries separate
// full hashes.
uint32_t numChars = aReadParams.mLimit - aReadParams.mBegin;
MOZ_ASSERT(numChars > sNumFastHashChars);
uint32_t fastHash = HashString(aReadParams.mBegin, sNumFastHashChars);
for (auto entry : aMetadata.mEntries) {
// Compare the "fast hash" first to see whether it is worthwhile to
// hash all the chars.
if (entry.mFastHash != fastHash) {
continue;
}
// Assuming we have enough characters, hash all the chars it would take
// to match this cache entry and compare to the cache entry. If we get a
// hit we'll still do a full source match later (in the JS engine), but
// the full hash match means this is probably the cache entry we want.
if (numChars < entry.mNumChars) {
continue;
}
uint32_t fullHash = HashString(aReadParams.mBegin, entry.mNumChars);
if (entry.mFullHash != fullHash) {
continue;
}
*aModuleIndex = entry.mModuleIndex;
return true;
}
return false;
}
} // unnamed namespace
PAsmJSCacheEntryParent* AllocEntryParent(OpenMode aOpenMode,
WriteParams aWriteParams,
const PrincipalInfo& aPrincipalInfo) {
AssertIsOnBackgroundThread();
if (NS_WARN_IF(Client::IsShuttingDownOnBackgroundThread())) {
return nullptr;
}
if (NS_WARN_IF(aPrincipalInfo.type() == PrincipalInfo::TNullPrincipalInfo)) {
MOZ_ASSERT(false);
return nullptr;
}
RefPtr<ParentRunnable> runnable =
new ParentRunnable(aPrincipalInfo, aOpenMode, aWriteParams);
if (!sLiveParentActors) {
sLiveParentActors = new ParentActorArray();
}
sLiveParentActors->AppendElement(runnable);
nsresult rv = NS_DispatchToMainThread(runnable);
NS_ENSURE_SUCCESS(rv, nullptr);
// Transfer ownership to IPDL.
return runnable.forget().take();
}
void DeallocEntryParent(PAsmJSCacheEntryParent* aActor) {
// Transfer ownership back from IPDL.
RefPtr<ParentRunnable> op = dont_AddRef(static_cast<ParentRunnable*>(aActor));
}
namespace {
// A runnable that presents a single interface to the AsmJSCache ops which need
// to wait until the file is open.
class ChildRunnable final : public FileDescriptorHolder,
public PAsmJSCacheEntryChild {
typedef mozilla::ipc::PBackgroundChild PBackgroundChild;
public:
class AutoClose {
ChildRunnable* mChildRunnable;
public:
explicit AutoClose(ChildRunnable* aChildRunnable = nullptr)
: mChildRunnable(aChildRunnable) {}
void Init(ChildRunnable* aChildRunnable) {
MOZ_ASSERT(!mChildRunnable);
mChildRunnable = aChildRunnable;
}
ChildRunnable* operator->() const MOZ_NO_ADDREF_RELEASE_ON_RETURN {
MOZ_ASSERT(mChildRunnable);
return mChildRunnable;
}
void Forget(ChildRunnable** aChildRunnable) {
*aChildRunnable = mChildRunnable;
mChildRunnable = nullptr;
}
~AutoClose() {
if (mChildRunnable) {
mChildRunnable->Close();
}
}
};
NS_DECL_NSIRUNNABLE
ChildRunnable(nsIPrincipal* aPrincipal, OpenMode aOpenMode,
const WriteParams& aWriteParams, ReadParams aReadParams)
: mPrincipal(aPrincipal),
mWriteParams(aWriteParams),
mReadParams(aReadParams),
mMutex("ChildRunnable::mMutex"),
mCondVar(mMutex, "ChildRunnable::mCondVar"),
mOpenMode(aOpenMode),
mState(eInitial),
mResult(JS::AsmJSCache_InternalError),
mActorDestroyed(false),
mWaiting(false),
mOpened(false) {
MOZ_ASSERT(!NS_IsMainThread());
}
JS::AsmJSCacheResult BlockUntilOpen(AutoClose* aCloser) {
MOZ_ASSERT(!mWaiting, "Can only call BlockUntilOpen once");
MOZ_ASSERT(!mOpened, "Can only call BlockUntilOpen once");
mWaiting = true;
nsresult rv = NS_DispatchToMainThread(this);
if (NS_WARN_IF(NS_FAILED(rv))) {
return JS::AsmJSCache_InternalError;
}
{
MutexAutoLock lock(mMutex);
while (mWaiting) {
mCondVar.Wait();
}
}
if (!mOpened) {
return mResult;
}
// Now that we're open, we're guaranteed a Close() call. However, we are
// not guaranteed someone is holding an outstanding reference until the File
// is closed, so we do that ourselves and Release() in OnClose().
aCloser->Init(this);
AddRef();
return JS::AsmJSCache_Success;
}
void Cleanup() {
#ifdef DEBUG
NoteActorDestroyed();
#endif
}
private:
~ChildRunnable() override {
MOZ_ASSERT(!mWaiting, "Shouldn't be destroyed while thread is waiting");
MOZ_ASSERT(!mOpened);
MOZ_ASSERT(mState == eFinished);
MOZ_ASSERT(mActorDestroyed);
}
// IPDL methods.
mozilla::ipc::IPCResult RecvOnOpenMetadataForRead(
const Metadata& aMetadata) override {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mState == eOpening);
uint32_t moduleIndex;
bool ok;
if (FindHashMatch(aMetadata, mReadParams, &moduleIndex)) {
ok = SendSelectCacheFileToRead(moduleIndex);
} else {
ok = SendSelectCacheFileToRead(JS::AsmJSCache_InternalError);
}
if (!ok) {
return IPC_FAIL_NO_REASON(this);
}
return IPC_OK();
}
mozilla::ipc::IPCResult RecvOnOpenCacheFile(
const int64_t& aFileSize, const FileDescriptor& aFileDesc) override {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mState == eOpening);
mFileSize = aFileSize;
auto rawFD = aFileDesc.ClonePlatformHandle();
mFileDesc = PR_ImportFile(PROsfd(rawFD.release()));
if (!mFileDesc) {
return IPC_FAIL_NO_REASON(this);
}
mState = eOpened;
Notify(JS::AsmJSCache_Success);
return IPC_OK();
}
mozilla::ipc::IPCResult Recv__delete__(
const JS::AsmJSCacheResult& aResult) override {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mState == eOpening || mState == eFinishing);
MOZ_ASSERT_IF(mState == eOpening, aResult != JS::AsmJSCache_Success);
MOZ_ASSERT_IF(mState == eFinishing, aResult == JS::AsmJSCache_Success);
if (mState == eOpening) {
Fail(aResult);
} else {
// Match the AddRef in BlockUntilOpen(). The IPDL still holds an
// outstanding ref which will keep 'this' alive until ActorDestroy()
// is executed.
Release();
mState = eFinished;
}
return IPC_OK();
}
void ActorDestroy(ActorDestroyReason why) override {
MOZ_ASSERT(NS_IsMainThread());
NoteActorDestroyed();
}
void Close() {
MOZ_ASSERT(mState == eOpened);
mState = eClosing;
NS_DispatchToMainThread(this);
}
void Fail(JS::AsmJSCacheResult aResult) {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mState == eInitial || mState == eOpening);
MOZ_ASSERT(aResult != JS::AsmJSCache_Success);
mState = eFinished;
FileDescriptorHolder::Finish();
Notify(aResult);
}
void Notify(JS::AsmJSCacheResult aResult) {
MOZ_ASSERT(NS_IsMainThread());
MutexAutoLock lock(mMutex);
MOZ_ASSERT(mWaiting);
mWaiting = false;
mOpened = aResult == JS::AsmJSCache_Success;
mResult = aResult;
mCondVar.Notify();
}
void NoteActorDestroyed() { mActorDestroyed = true; }
nsIPrincipal* const mPrincipal;
nsAutoPtr<PrincipalInfo> mPrincipalInfo;
WriteParams mWriteParams;
ReadParams mReadParams;
Mutex mMutex;
CondVar mCondVar;
// Couple enums and bools together
const OpenMode mOpenMode;
enum State {
eInitial, // Just created, waiting to be dispatched to the main thread
eOpening, // Waiting for the parent process to respond
eOpened, // Parent process opened the entry and sent it back
eClosing, // Waiting to be dispatched to the main thread to Send__delete__
eFinishing, // Waiting for the parent process to close
eFinished // Terminal state
};
State mState;
JS::AsmJSCacheResult mResult;
bool mActorDestroyed;
bool mWaiting;
bool mOpened;
};
NS_IMETHODIMP
ChildRunnable::Run() {
switch (mState) {
case eInitial: {
MOZ_ASSERT(NS_IsMainThread());
if (mPrincipal->GetIsNullPrincipal()) {
NS_WARNING("AsmsJSCache not supported on null principal.");
Fail(JS::AsmJSCache_InternalError);
return NS_OK;
}
nsAutoPtr<PrincipalInfo> principalInfo(new PrincipalInfo());
nsresult rv = PrincipalToPrincipalInfo(mPrincipal, principalInfo);
if (NS_WARN_IF(NS_FAILED(rv))) {
Fail(JS::AsmJSCache_InternalError);
return NS_OK;
}
mPrincipalInfo = std::move(principalInfo);
PBackgroundChild* actor = BackgroundChild::GetOrCreateForCurrentThread();
if (NS_WARN_IF(!actor)) {
Fail(JS::AsmJSCache_InternalError);
return NS_OK;
}
if (!actor->SendPAsmJSCacheEntryConstructor(this, mOpenMode, mWriteParams,
*mPrincipalInfo)) {
// Unblock the parsing thread with a failure.
Fail(JS::AsmJSCache_InternalError);
return NS_OK;
}
// AddRef to keep this runnable alive until IPDL deallocates the
// subprotocol (DeallocEntryChild).
AddRef();
mState = eOpening;
return NS_OK;
}
case eClosing: {
MOZ_ASSERT(NS_IsMainThread());
// Per FileDescriptorHolder::Finish()'s comment, call before
// releasing the directory lock (which happens in the parent upon receipt
// of the Close message).
FileDescriptorHolder::Finish();
MOZ_ASSERT(mOpened);
mOpened = false;
if (mActorDestroyed) {
// Match the AddRef in BlockUntilOpen(). The main thread event loop
// still holds an outstanding ref which will keep 'this' alive until
// returning to the event loop.
Release();
mState = eFinished;
} else {
Unused << SendClose();
mState = eFinishing;
}
return NS_OK;
}
case eOpening:
case eOpened:
case eFinishing:
case eFinished: {
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Shouldn't Run() in this state");
}
}
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Corrupt state");
return NS_OK;
}
} // unnamed namespace
void DeallocEntryChild(PAsmJSCacheEntryChild* aActor) {
// Match the AddRef before SendPAsmJSCacheEntryConstructor.
static_cast<ChildRunnable*>(aActor)->Release();
}
namespace {
JS::AsmJSCacheResult OpenFile(nsIPrincipal* aPrincipal, OpenMode aOpenMode,
WriteParams aWriteParams, ReadParams aReadParams,
ChildRunnable::AutoClose* aChildRunnable) {
MOZ_ASSERT_IF(aOpenMode == eOpenForRead, aWriteParams.mSize == 0);
MOZ_ASSERT_IF(aOpenMode == eOpenForWrite, aReadParams.mBegin == nullptr);
// There are three reasons we don't attempt caching from the main thread:
// 1. In the parent process: QuotaManager::WaitForOpenAllowed prevents
// synchronous waiting on the main thread requiring a runnable to be
// dispatched to the main thread.
// 2. In the child process: the IPDL PContent messages we need to
// synchronously wait on are dispatched to the main thread.
// 3. While a cache lookup *should* be much faster than compilation, IO
// operations can be unpredictably slow and we'd like to avoid the
// occasional janks on the main thread.
// We could use a nested event loop to address 1 and 2, but we're potentially
// in the middle of running JS (eval()) and nested event loops can be
// semantically observable.
if (NS_IsMainThread()) {
return JS::AsmJSCache_SynchronousScript;
}
// Check to see whether the principal reflects a private browsing session.
// Since AsmJSCache requires disk access at the moment, caching should be
// disabled in private browsing situations. Failing here will cause later
// read/write requests to also fail.
uint32_t pbId;
if (NS_WARN_IF(NS_FAILED(aPrincipal->GetPrivateBrowsingId(&pbId)))) {
return JS::AsmJSCache_InternalError;
}
if (pbId > 0) {
return JS::AsmJSCache_Disabled_PrivateBrowsing;
}
// We need to synchronously call into the parent to open the file and
// interact with the QuotaManager. The child can then map the file into its
// address space to perform I/O.
RefPtr<ChildRunnable> childRunnable =
new ChildRunnable(aPrincipal, aOpenMode, aWriteParams, aReadParams);
JS::AsmJSCacheResult openResult =
childRunnable->BlockUntilOpen(aChildRunnable);
if (openResult != JS::AsmJSCache_Success) {
childRunnable->Cleanup();
return openResult;
}
if (!childRunnable->MapMemory(aOpenMode)) {
return JS::AsmJSCache_InternalError;
}
return JS::AsmJSCache_Success;
}
} // namespace
typedef uint32_t AsmJSCookieType;
static const uint32_t sAsmJSCookie = 0x600d600d;
bool OpenEntryForRead(nsIPrincipal* aPrincipal, const char16_t* aBegin,
const char16_t* aLimit, size_t* aSize,
const uint8_t** aMemory, intptr_t* aHandle) {
if (size_t(aLimit - aBegin) < sMinCachedModuleLength) {
return false;
}
ReadParams readParams;
readParams.mBegin = aBegin;
readParams.mLimit = aLimit;
ChildRunnable::AutoClose childRunnable;
WriteParams notAWrite;
JS::AsmJSCacheResult openResult =
OpenFile(aPrincipal, eOpenForRead, notAWrite, readParams, &childRunnable);
if (openResult != JS::AsmJSCache_Success) {
return false;
}
// Although we trust that the stored cache files have not been arbitrarily
// corrupted, it is possible that a previous execution aborted in the middle
// of writing a cache file (crash, OOM-killer, etc). To protect against
// partially-written cache files, we use the following scheme:
// - Allocate an extra word at the beginning of every cache file which
// starts out 0 (OpenFile opens with PR_TRUNCATE).
// - After the asm.js serialization is complete, PR_SyncMemMap to write
// everything to disk and then store a non-zero value (sAsmJSCookie)
// in the first word.
// - When attempting to read a cache file, check whether the first word is
// sAsmJSCookie.
if (childRunnable->FileSize() < sizeof(AsmJSCookieType) ||
*(AsmJSCookieType*)childRunnable->MappedMemory() != sAsmJSCookie) {
return false;
}
*aSize = childRunnable->FileSize() - sizeof(AsmJSCookieType);
*aMemory = (uint8_t*)childRunnable->MappedMemory() + sizeof(AsmJSCookieType);
// The caller guarnatees a call to CloseEntryForRead (on success or
// failure) at which point the file will be closed.
childRunnable.Forget(reinterpret_cast<ChildRunnable**>(aHandle));
return true;
}
void CloseEntryForRead(size_t aSize, const uint8_t* aMemory, intptr_t aHandle) {
ChildRunnable::AutoClose childRunnable(
reinterpret_cast<ChildRunnable*>(aHandle));
MOZ_ASSERT(aSize + sizeof(AsmJSCookieType) == childRunnable->FileSize());
MOZ_ASSERT(aMemory - sizeof(AsmJSCookieType) ==
childRunnable->MappedMemory());
}
JS::AsmJSCacheResult OpenEntryForWrite(nsIPrincipal* aPrincipal,
const char16_t* aBegin,
const char16_t* aEnd, size_t aSize,
uint8_t** aMemory, intptr_t* aHandle) {
if (size_t(aEnd - aBegin) < sMinCachedModuleLength) {
return JS::AsmJSCache_ModuleTooSmall;
}
// Add extra space for the AsmJSCookieType (see OpenEntryForRead).
aSize += sizeof(AsmJSCookieType);
static_assert(sNumFastHashChars < sMinCachedModuleLength, "HashString safe");
WriteParams writeParams;
writeParams.mSize = aSize;
writeParams.mFastHash = HashString(aBegin, sNumFastHashChars);
writeParams.mNumChars = aEnd - aBegin;
writeParams.mFullHash = HashString(aBegin, writeParams.mNumChars);
ChildRunnable::AutoClose childRunnable;
ReadParams notARead;
JS::AsmJSCacheResult openResult = OpenFile(
aPrincipal, eOpenForWrite, writeParams, notARead, &childRunnable);
if (openResult != JS::AsmJSCache_Success) {
return openResult;
}
// Strip off the AsmJSCookieType from the buffer returned to the caller,
// which expects a buffer of aSize, not a buffer of sizeWithCookie starting
// with a cookie.
*aMemory = (uint8_t*)childRunnable->MappedMemory() + sizeof(AsmJSCookieType);
// The caller guarnatees a call to CloseEntryForWrite (on success or
// failure) at which point the file will be closed
childRunnable.Forget(reinterpret_cast<ChildRunnable**>(aHandle));
return JS::AsmJSCache_Success;
}
void CloseEntryForWrite(size_t aSize, uint8_t* aMemory, intptr_t aHandle) {
ChildRunnable::AutoClose childRunnable(
reinterpret_cast<ChildRunnable*>(aHandle));
MOZ_ASSERT(aSize + sizeof(AsmJSCookieType) == childRunnable->FileSize());
MOZ_ASSERT(aMemory - sizeof(AsmJSCookieType) ==
childRunnable->MappedMemory());
// Flush to disk before writing the cookie (see OpenEntryForRead).
if (PR_SyncMemMap(childRunnable->FileDesc(), childRunnable->MappedMemory(),
childRunnable->FileSize()) == PR_SUCCESS) {
*(AsmJSCookieType*)childRunnable->MappedMemory() = sAsmJSCookie;
}
}
/*******************************************************************************
* Client
******************************************************************************/
Client* Client::sInstance = nullptr;
Client::Client() : mShutdownRequested(false) {
AssertIsOnBackgroundThread();
MOZ_ASSERT(!sInstance, "We expect this to be a singleton!");
sInstance = this;
}
Client::~Client() {
AssertIsOnBackgroundThread();
MOZ_ASSERT(sInstance == this, "We expect this to be a singleton!");
sInstance = nullptr;
}
Client::Type Client::GetType() { return ASMJS; }
nsresult Client::InitOrigin(PersistenceType aPersistenceType,
const nsACString& aGroup, const nsACString& aOrigin,
const AtomicBool& aCanceled,
UsageInfo* aUsageInfo) {
if (!aUsageInfo) {
return NS_OK;
}
return GetUsageForOrigin(aPersistenceType, aGroup, aOrigin, aCanceled,
aUsageInfo);
}
nsresult Client::GetUsageForOrigin(PersistenceType aPersistenceType,
const nsACString& aGroup,
const nsACString& aOrigin,
const AtomicBool& aCanceled,
UsageInfo* aUsageInfo) {
QuotaManager* qm = QuotaManager::Get();
MOZ_ASSERT(qm, "We were being called by the QuotaManager");
nsCOMPtr<nsIFile> directory;
nsresult rv = qm->GetDirectoryForOrigin(aPersistenceType, aOrigin,
getter_AddRefs(directory));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
MOZ_ASSERT(directory, "We're here because the origin directory exists");
rv = directory->Append(NS_LITERAL_STRING(ASMJSCACHE_DIRECTORY_NAME));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
DebugOnly<bool> exists;
MOZ_ASSERT(NS_SUCCEEDED(directory->Exists(&exists)) && exists);
nsCOMPtr<nsIDirectoryEnumerator> entries;
rv = directory->GetDirectoryEntries(getter_AddRefs(entries));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
nsCOMPtr<nsIFile> file;
while (NS_SUCCEEDED((rv = entries->GetNextFile(getter_AddRefs(file)))) &&
file && !aCanceled) {
int64_t fileSize;
rv = file->GetFileSize(&fileSize);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
MOZ_ASSERT(fileSize >= 0, "Negative size?!");
// Since the client is not explicitly storing files, append to database
// usage which represents implicit storage allocation.
aUsageInfo->AppendToDatabaseUsage(uint64_t(fileSize));
}
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
return NS_OK;
}
void Client::OnOriginClearCompleted(PersistenceType aPersistenceType,
const nsACString& aOrigin) {}
void Client::ReleaseIOThreadObjects() {}
void Client::AbortOperations(const nsACString& aOrigin) {}
void Client::AbortOperationsForProcess(ContentParentId aContentParentId) {}
void Client::StartIdleMaintenance() {}
void Client::StopIdleMaintenance() {}
void Client::ShutdownWorkThreads() {
AssertIsOnBackgroundThread();
MOZ_ASSERT(!mShutdownRequested);
mShutdownRequested = true;
if (sLiveParentActors) {
MOZ_ALWAYS_TRUE(SpinEventLoopUntil([&]() { return !sLiveParentActors; }));
}
}
quota::Client* CreateClient() { return new Client(); }
} // namespace asmjscache
} // namespace dom
} // namespace mozilla
namespace IPC {
using mozilla::dom::asmjscache::Metadata;
using mozilla::dom::asmjscache::WriteParams;
void ParamTraits<Metadata>::Write(Message* aMsg, const paramType& aParam) {
for (auto entry : aParam.mEntries) {
WriteParam(aMsg, entry.mFastHash);
WriteParam(aMsg, entry.mNumChars);
WriteParam(aMsg, entry.mFullHash);
WriteParam(aMsg, entry.mModuleIndex);
}
}
bool ParamTraits<Metadata>::Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
for (auto& entry : aResult->mEntries) {
if (!ReadParam(aMsg, aIter, &entry.mFastHash) ||
!ReadParam(aMsg, aIter, &entry.mNumChars) ||
!ReadParam(aMsg, aIter, &entry.mFullHash) ||
!ReadParam(aMsg, aIter, &entry.mModuleIndex)) {
return false;
}
}
return true;
}
void ParamTraits<Metadata>::Log(const paramType& aParam, std::wstring* aLog) {
for (auto entry : aParam.mEntries) {
LogParam(entry.mFastHash, aLog);
LogParam(entry.mNumChars, aLog);
LogParam(entry.mFullHash, aLog);
LogParam(entry.mModuleIndex, aLog);
}
}
void ParamTraits<WriteParams>::Write(Message* aMsg, const paramType& aParam) {
WriteParam(aMsg, aParam.mSize);
WriteParam(aMsg, aParam.mFastHash);
WriteParam(aMsg, aParam.mNumChars);
WriteParam(aMsg, aParam.mFullHash);
}
bool ParamTraits<WriteParams>::Read(const Message* aMsg, PickleIterator* aIter,
paramType* aResult) {
return ReadParam(aMsg, aIter, &aResult->mSize) &&
ReadParam(aMsg, aIter, &aResult->mFastHash) &&
ReadParam(aMsg, aIter, &aResult->mNumChars) &&
ReadParam(aMsg, aIter, &aResult->mFullHash);
}
void ParamTraits<WriteParams>::Log(const paramType& aParam,
std::wstring* aLog) {
LogParam(aParam.mSize, aLog);
LogParam(aParam.mFastHash, aLog);
LogParam(aParam.mNumChars, aLog);
LogParam(aParam.mFullHash, aLog);
}
} // namespace IPC
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку