//* Copyright 2017 The Dawn Authors //* //* 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. #include "dawn_wire/Wire.h" #include "dawn_wire/WireCmd.h" #include "common/Assert.h" #include #include #include #include #include namespace dawn_wire { namespace server { class Server; struct MapUserdata { Server* server; uint32_t bufferId; uint32_t bufferSerial; uint32_t requestSerial; uint32_t size; bool isWrite; }; struct FenceCompletionUserdata { Server* server; uint32_t fenceId; uint32_t fenceSerial; uint64_t value; }; //* Stores what the backend knows about the type. template struct ObjectDataBase { //* The backend-provided handle and serial to this object. T handle; uint32_t serial = 0; //* Built object ID and serial, needed to send to the client along with builder error callbacks //* TODO(cwallez@chromium.org) only have this for builder T uint32_t builtObjectId = 0; uint32_t builtObjectSerial = 0; //* Used by the error-propagation mechanism to know if this object is an error. //* TODO(cwallez@chromium.org): this is doubling the memory usage of //* std::vector consider making it a special marker value in handle instead. bool valid; //* Whether this object has been allocated, used by the KnownObjects queries //* TODO(cwallez@chromium.org): make this an internal bit vector in KnownObjects. bool allocated; //* TODO(cwallez@chromium.org): this is only useful for buffers void* mappedData = nullptr; size_t mappedDataSize = 0; }; //* Keeps track of the mapping between client IDs and backend objects. template class KnownObjects { public: using Data = ObjectDataBase; KnownObjects() { //* Pre-allocate ID 0 to refer to the null handle. Data nullObject; nullObject.handle = nullptr; nullObject.valid = true; nullObject.allocated = true; mKnown.push_back(nullObject); } //* Get a backend objects for a given client ID. //* Returns nullptr if the ID hasn't previously been allocated. const Data* Get(uint32_t id) const { if (id >= mKnown.size()) { return nullptr; } const Data* data = &mKnown[id]; if (!data->allocated) { return nullptr; } return data; } Data* Get(uint32_t id) { if (id >= mKnown.size()) { return nullptr; } Data* data = &mKnown[id]; if (!data->allocated) { return nullptr; } return data; } //* Allocates the data for a given ID and returns it. //* Returns nullptr if the ID is already allocated, or too far ahead. //* Invalidates all the Data* Data* Allocate(uint32_t id) { if (id > mKnown.size()) { return nullptr; } Data data; data.allocated = true; data.valid = false; data.handle = nullptr; if (id >= mKnown.size()) { mKnown.push_back(data); return &mKnown.back(); } if (mKnown[id].allocated) { return nullptr; } mKnown[id] = data; return &mKnown[id]; } //* Marks an ID as deallocated void Free(uint32_t id) { ASSERT(id < mKnown.size()); mKnown[id].allocated = false; } private: std::vector mKnown; }; // ObjectIds are lost in deserialization. Store the ids of deserialized // objects here so they can be used in command handlers. This is useful // for creating ReturnWireCmds which contain client ids template class ObjectIdLookupTable { public: void Store(T key, ObjectId id) { mTable[key] = id; } // Return the cached ObjectId, or 0 (null handle) ObjectId Get(T key) const { const auto it = mTable.find(key); if (it != mTable.end()) { return it->second; } return 0; } void Remove(T key) { auto it = mTable.find(key); if (it != mTable.end()) { mTable.erase(it); } } private: std::map mTable; }; void ForwardDeviceErrorToServer(const char* message, dawnCallbackUserdata userdata); {% for type in by_category["object"] if type.is_builder%} void Forward{{type.name.CamelCase()}}ToClient(dawnBuilderErrorStatus status, const char* message, dawnCallbackUserdata userdata1, dawnCallbackUserdata userdata2); {% endfor %} void ForwardBufferMapReadAsync(dawnBufferMapAsyncStatus status, const void* ptr, dawnCallbackUserdata userdata); void ForwardBufferMapWriteAsync(dawnBufferMapAsyncStatus status, void* ptr, dawnCallbackUserdata userdata); void ForwardFenceCompletedValue(dawnFenceCompletionStatus status, dawnCallbackUserdata userdata); // A really really simple implementation of the DeserializeAllocator. It's main feature // is that it has some inline storage so as to avoid allocations for the majority of // commands. class ServerAllocator : public DeserializeAllocator { public: ServerAllocator() { Reset(); } ~ServerAllocator() { Reset(); } void* GetSpace(size_t size) override { // Return space in the current buffer if possible first. if (mRemainingSize >= size) { char* buffer = mCurrentBuffer; mCurrentBuffer += size; mRemainingSize -= size; return buffer; } // Otherwise allocate a new buffer and try again. size_t allocationSize = std::max(size, size_t(2048)); char* allocation = static_cast(malloc(allocationSize)); if (allocation == nullptr) { return nullptr; } mAllocations.push_back(allocation); mCurrentBuffer = allocation; mRemainingSize = allocationSize; return GetSpace(size); } void Reset() { for (auto allocation : mAllocations) { free(allocation); } mAllocations.clear(); // The initial buffer is the inline buffer so that some allocations can be skipped mCurrentBuffer = mStaticBuffer; mRemainingSize = sizeof(mStaticBuffer); } private: size_t mRemainingSize = 0; char* mCurrentBuffer = nullptr; char mStaticBuffer[2048]; std::vector mAllocations; }; class Server : public CommandHandler, public ObjectIdResolver { public: Server(dawnDevice device, const dawnProcTable& procs, CommandSerializer* serializer) : mProcs(procs), mSerializer(serializer) { //* The client-server knowledge is bootstrapped with device 1. auto* deviceData = mKnownDevice.Allocate(1); deviceData->handle = device; deviceData->valid = true; auto userdata = static_cast(reinterpret_cast(this)); procs.deviceSetErrorCallback(device, ForwardDeviceErrorToServer, userdata); } void OnDeviceError(const char* message) { ReturnDeviceErrorCallbackCmd cmd; cmd.messageStrlen = std::strlen(message); auto allocCmd = static_cast(GetCmdSpace(sizeof(cmd))); *allocCmd = cmd; char* messageAlloc = static_cast(GetCmdSpace(cmd.messageStrlen + 1)); strcpy(messageAlloc, message); } {% for type in by_category["object"] if type.is_builder%} {% set Type = type.name.CamelCase() %} void On{{Type}}Error(dawnBuilderErrorStatus status, const char* message, uint32_t id, uint32_t serial) { auto* builder = mKnown{{Type}}.Get(id); if (builder == nullptr || builder->serial != serial) { return; } if (status != DAWN_BUILDER_ERROR_STATUS_SUCCESS) { builder->valid = false; } if (status != DAWN_BUILDER_ERROR_STATUS_UNKNOWN) { //* Unknown is the only status that can be returned without a call to GetResult //* so we are guaranteed to have created an object. ASSERT(builder->builtObjectId != 0); Return{{Type}}ErrorCallbackCmd cmd; cmd.builtObjectId = builder->builtObjectId; cmd.builtObjectSerial = builder->builtObjectSerial; cmd.status = status; cmd.messageStrlen = std::strlen(message); auto allocCmd = static_cast(GetCmdSpace(sizeof(cmd))); *allocCmd = cmd; char* messageAlloc = static_cast(GetCmdSpace(strlen(message) + 1)); strcpy(messageAlloc, message); } } {% endfor %} void OnMapReadAsyncCallback(dawnBufferMapAsyncStatus status, const void* ptr, MapUserdata* data) { ReturnBufferMapReadAsyncCallbackCmd cmd; cmd.bufferId = data->bufferId; cmd.bufferSerial = data->bufferSerial; cmd.requestSerial = data->requestSerial; cmd.status = status; cmd.dataLength = 0; auto allocCmd = static_cast(GetCmdSpace(sizeof(cmd))); *allocCmd = cmd; if (status == DAWN_BUFFER_MAP_ASYNC_STATUS_SUCCESS) { allocCmd->dataLength = data->size; void* dataAlloc = GetCmdSpace(data->size); memcpy(dataAlloc, ptr, data->size); } delete data; } void OnMapWriteAsyncCallback(dawnBufferMapAsyncStatus status, void* ptr, MapUserdata* data) { ReturnBufferMapWriteAsyncCallbackCmd cmd; cmd.bufferId = data->bufferId; cmd.bufferSerial = data->bufferSerial; cmd.requestSerial = data->requestSerial; cmd.status = status; auto allocCmd = static_cast(GetCmdSpace(sizeof(cmd))); *allocCmd = cmd; if (status == DAWN_BUFFER_MAP_ASYNC_STATUS_SUCCESS) { auto* selfData = mKnownBuffer.Get(data->bufferId); ASSERT(selfData != nullptr); selfData->mappedData = ptr; selfData->mappedDataSize = data->size; } delete data; } void OnFenceCompletedValueUpdated(FenceCompletionUserdata* data) { ReturnFenceUpdateCompletedValueCmd cmd; cmd.fenceId = data->fenceId; cmd.fenceSerial = data->fenceSerial; cmd.value = data->value; auto allocCmd = static_cast(GetCmdSpace(sizeof(cmd))); *allocCmd = cmd; delete data; } {% set client_side_commands = ["FenceGetCompletedValue"] %} const char* HandleCommands(const char* commands, size_t size) override { mProcs.deviceTick(mKnownDevice.Get(1)->handle); while (size >= sizeof(WireCmd)) { WireCmd cmdId = *reinterpret_cast(commands); bool success = false; switch (cmdId) { {% for type in by_category["object"] %} {% for method in type.methods %} {% set Suffix = as_MethodSuffix(type.name, method.name) %} {% if Suffix not in client_side_commands %} case WireCmd::{{Suffix}}: success = Handle{{Suffix}}(&commands, &size); break; {% endif %} {% endfor %} {% set Suffix = as_MethodSuffix(type.name, Name("destroy")) %} case WireCmd::{{Suffix}}: success = Handle{{Suffix}}(&commands, &size); break; {% endfor %} case WireCmd::BufferMapAsync: success = HandleBufferMapAsync(&commands, &size); break; case WireCmd::BufferUpdateMappedDataCmd: success = HandleBufferUpdateMappedData(&commands, &size); break; default: success = false; } if (!success) { return nullptr; } mAllocator.Reset(); } if (size != 0) { return nullptr; } return commands; } private: dawnProcTable mProcs; CommandSerializer* mSerializer = nullptr; ServerAllocator mAllocator; void* GetCmdSpace(size_t size) { return mSerializer->GetCmdSpace(size); } // Implementation of the ObjectIdResolver interface {% for type in by_category["object"] %} DeserializeResult GetFromId(ObjectId id, {{as_cType(type.name)}}* out) const final { auto data = mKnown{{type.name.CamelCase()}}.Get(id); if (data == nullptr) { return DeserializeResult::FatalError; } *out = data->handle; if (data->valid) { return DeserializeResult::Success; } else { return DeserializeResult::ErrorObject; } } DeserializeResult GetOptionalFromId(ObjectId id, {{as_cType(type.name)}}* out) const final { if (id == 0) { *out = nullptr; return DeserializeResult::Success; } return GetFromId(id, out); } {% endfor %} //* The list of known IDs for each object type. {% for type in by_category["object"] %} KnownObjects<{{as_cType(type.name)}}> mKnown{{type.name.CamelCase()}}; {% endfor %} {% set reverse_lookup_object_types = ["Fence"] %} {% for type in by_category["object"] if type.name.CamelCase() in reverse_lookup_object_types %} ObjectIdLookupTable<{{as_cType(type.name)}}> m{{type.name.CamelCase()}}IdTable; {% endfor %} //* Helper function for the getting of the command data in command handlers. //* Checks there is enough data left, updates the buffer / size and returns //* the command (or nullptr for an error). template static const T* GetData(const char** buffer, size_t* size, size_t count) { // TODO(cwallez@chromium.org): Check for overflow size_t totalSize = count * sizeof(T); if (*size < totalSize) { return nullptr; } const T* data = reinterpret_cast(*buffer); *buffer += totalSize; *size -= totalSize; return data; } template static const T* GetCommand(const char** commands, size_t* size) { return GetData(commands, size, 1); } {% set custom_pre_handler_commands = ["BufferUnmap"] %} bool PreHandleBufferUnmap(const BufferUnmapCmd& cmd) { auto* selfData = mKnownBuffer.Get(cmd.selfId); ASSERT(selfData != nullptr); selfData->mappedData = nullptr; return true; } {% set custom_post_handler_commands = ["QueueSignal"] %} bool PostHandleQueueSignal(const QueueSignalCmd& cmd) { ObjectId fenceId = mFenceIdTable.Get(cmd.fence); ASSERT(fenceId != 0); auto* fence = mKnownFence.Get(fenceId); ASSERT(fence != nullptr); auto* data = new FenceCompletionUserdata; data->server = this; data->fenceId = fenceId; data->fenceSerial = fence->serial; data->value = cmd.signalValue; auto userdata = static_cast(reinterpret_cast(data)); mProcs.fenceOnCompletion(cmd.fence, cmd.signalValue, ForwardFenceCompletedValue, userdata); return true; } //* Implementation of the command handlers {% for type in by_category["object"] %} {% for method in type.methods %} {% set Suffix = as_MethodSuffix(type.name, method.name) %} {% if Suffix not in client_side_commands %} //* The generic command handlers bool Handle{{Suffix}}(const char** commands, size_t* size) { {{Suffix}}Cmd cmd; DeserializeResult deserializeResult = cmd.Deserialize(commands, size, &mAllocator, *this); if (deserializeResult == DeserializeResult::FatalError) { return false; } {% if Suffix in custom_pre_handler_commands %} if (!PreHandle{{Suffix}}(cmd)) { return false; } {% endif %} //* Unpack 'self' auto* selfData = mKnown{{type.name.CamelCase()}}.Get(cmd.selfId); ASSERT(selfData != nullptr); //* In all cases allocate the object data as it will be refered-to by the client. {% set return_type = method.return_type %} {% set returns = return_type.name.canonical_case() != "void" %} {% if returns %} {% set Type = method.return_type.name.CamelCase() %} auto* resultData = mKnown{{Type}}.Allocate(cmd.resultId); if (resultData == nullptr) { return false; } resultData->serial = cmd.resultSerial; {% if type.is_builder %} selfData->builtObjectId = cmd.resultId; selfData->builtObjectSerial = cmd.resultSerial; {% endif %} {% endif %} //* After the data is allocated, apply the argument error propagation mechanism if (deserializeResult == DeserializeResult::ErrorObject) { {% if type.is_builder %} selfData->valid = false; //* If we are in GetResult, fake an error callback {% if returns %} On{{type.name.CamelCase()}}Error(DAWN_BUILDER_ERROR_STATUS_ERROR, "Maybe monad", cmd.selfId, selfData->serial); {% endif %} {% endif %} return true; } {% if returns %} auto result ={{" "}} {%- endif %} mProcs.{{as_varName(type.name, method.name)}}(cmd.self {%- for arg in method.arguments -%} , cmd.{{as_varName(arg.name)}} {%- endfor -%} ); {% if Suffix in custom_post_handler_commands %} if (!PostHandle{{Suffix}}(cmd)) { return false; } {% endif %} {% if returns %} resultData->handle = result; resultData->valid = result != nullptr; {% if return_type.name.CamelCase() in reverse_lookup_object_types %} //* For created objects, store a mapping from them back to their client IDs if (result) { m{{return_type.name.CamelCase()}}IdTable.Store(result, cmd.resultId); } {% endif %} //* builders remember the ID of the object they built so that they can send it //* in the callback to the client. {% if return_type.is_builder %} if (result != nullptr) { uint64_t userdata1 = static_cast(reinterpret_cast(this)); uint64_t userdata2 = (uint64_t(resultData->serial) << uint64_t(32)) + cmd.resultId; mProcs.{{as_varName(return_type.name, Name("set error callback"))}}(result, Forward{{return_type.name.CamelCase()}}ToClient, userdata1, userdata2); } {% endif %} {% endif %} return true; } {% endif %} {% endfor %} //* Handlers for the destruction of objects: clients do the tracking of the //* reference / release and only send destroy on refcount = 0. {% set Suffix = as_MethodSuffix(type.name, Name("destroy")) %} bool Handle{{Suffix}}(const char** commands, size_t* size) { const auto* cmd = GetCommand<{{Suffix}}Cmd>(commands, size); if (cmd == nullptr) { return false; } ObjectId objectId = cmd->objectId; //* ID 0 are reserved for nullptr and cannot be destroyed. if (objectId == 0) { return false; } auto* data = mKnown{{type.name.CamelCase()}}.Get(objectId); if (data == nullptr) { return false; } {% if type.name.CamelCase() in reverse_lookup_object_types %} m{{type.name.CamelCase()}}IdTable.Remove(data->handle); {% endif %} if (data->valid) { mProcs.{{as_varName(type.name, Name("release"))}}(data->handle); } mKnown{{type.name.CamelCase()}}.Free(objectId); return true; } {% endfor %} bool HandleBufferMapAsync(const char** commands, size_t* size) { //* These requests are just forwarded to the buffer, with userdata containing what the client //* will require in the return command. const auto* cmd = GetCommand(commands, size); if (cmd == nullptr) { return false; } ObjectId bufferId = cmd->bufferId; uint32_t requestSerial = cmd->requestSerial; uint32_t requestSize = cmd->size; uint32_t requestStart = cmd->start; bool isWrite = cmd->isWrite; //* The null object isn't valid as `self` if (bufferId == 0) { return false; } auto* buffer = mKnownBuffer.Get(bufferId); if (buffer == nullptr) { return false; } auto* data = new MapUserdata; data->server = this; data->bufferId = bufferId; data->bufferSerial = buffer->serial; data->requestSerial = requestSerial; data->size = requestSize; data->isWrite = isWrite; auto userdata = static_cast(reinterpret_cast(data)); if (!buffer->valid) { //* Fake the buffer returning a failure, data will be freed in this call. if (isWrite) { ForwardBufferMapWriteAsync(DAWN_BUFFER_MAP_ASYNC_STATUS_ERROR, nullptr, userdata); } else { ForwardBufferMapReadAsync(DAWN_BUFFER_MAP_ASYNC_STATUS_ERROR, nullptr, userdata); } return true; } if (isWrite) { mProcs.bufferMapWriteAsync(buffer->handle, requestStart, requestSize, ForwardBufferMapWriteAsync, userdata); } else { mProcs.bufferMapReadAsync(buffer->handle, requestStart, requestSize, ForwardBufferMapReadAsync, userdata); } return true; } bool HandleBufferUpdateMappedData(const char** commands, size_t* size) { const auto* cmd = GetCommand(commands, size); if (cmd == nullptr) { return false; } ObjectId bufferId = cmd->bufferId; size_t dataLength = cmd->dataLength; //* The null object isn't valid as `self` if (bufferId == 0) { return false; } auto* buffer = mKnownBuffer.Get(bufferId); if (buffer == nullptr || !buffer->valid || buffer->mappedData == nullptr || buffer->mappedDataSize != dataLength) { return false; } const char* data = GetData(commands, size, dataLength); if (data == nullptr) { return false; } memcpy(buffer->mappedData, data, dataLength); return true; } }; void ForwardDeviceErrorToServer(const char* message, dawnCallbackUserdata userdata) { auto server = reinterpret_cast(static_cast(userdata)); server->OnDeviceError(message); } {% for type in by_category["object"] if type.is_builder%} void Forward{{type.name.CamelCase()}}ToClient(dawnBuilderErrorStatus status, const char* message, dawnCallbackUserdata userdata1, dawnCallbackUserdata userdata2) { auto server = reinterpret_cast(static_cast(userdata1)); uint32_t id = userdata2 & 0xFFFFFFFFu; uint32_t serial = userdata2 >> uint64_t(32); server->On{{type.name.CamelCase()}}Error(status, message, id, serial); } {% endfor %} void ForwardBufferMapReadAsync(dawnBufferMapAsyncStatus status, const void* ptr, dawnCallbackUserdata userdata) { auto data = reinterpret_cast(static_cast(userdata)); data->server->OnMapReadAsyncCallback(status, ptr, data); } void ForwardBufferMapWriteAsync(dawnBufferMapAsyncStatus status, void* ptr, dawnCallbackUserdata userdata) { auto data = reinterpret_cast(static_cast(userdata)); data->server->OnMapWriteAsyncCallback(status, ptr, data); } void ForwardFenceCompletedValue(dawnFenceCompletionStatus status, dawnCallbackUserdata userdata) { auto data = reinterpret_cast(static_cast(userdata)); if (status == DAWN_FENCE_COMPLETION_STATUS_SUCCESS) { data->server->OnFenceCompletedValueUpdated(data); } } } CommandHandler* NewServerCommandHandler(dawnDevice device, const dawnProcTable& procs, CommandSerializer* serializer) { return new server::Server(device, procs, serializer); } } // namespace dawn_wire