Kernel: Basic support for IPC translation for HLE services

This commit is contained in:
Yuri Kunde Schlesner 2017-06-09 05:23:13 -07:00
parent 7656d83df5
commit 8cb65fe65a
3 changed files with 130 additions and 18 deletions

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@ -8,6 +8,7 @@
#include "core/hle/kernel/handle_table.h"
#include "core/hle/kernel/hle_ipc.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/server_session.h"
namespace Kernel {
@ -24,12 +25,97 @@ void SessionRequestHandler::ClientDisconnected(SharedPtr<ServerSession> server_s
HLERequestContext::~HLERequestContext() = default;
SharedPtr<Object> HLERequestContext::GetIncomingHandle(Handle id_from_cmdbuf) const {
return Kernel::g_handle_table.GetGeneric(id_from_cmdbuf);
SharedPtr<Object> HLERequestContext::GetIncomingHandle(u32 id_from_cmdbuf) const {
ASSERT(id_from_cmdbuf < request_handles.size());
return request_handles[id_from_cmdbuf];
}
Handle HLERequestContext::AddOutgoingHandle(SharedPtr<Object> object) {
return Kernel::g_handle_table.Create(object).Unwrap();
u32 HLERequestContext::AddOutgoingHandle(SharedPtr<Object> object) {
request_handles.push_back(std::move(object));
return request_handles.size() - 1;
}
ResultCode HLERequestContext::PopulateFromIncomingCommandBuffer(const u32_le* src_cmdbuf,
Process& src_process,
HandleTable& src_table) {
IPC::Header header{src_cmdbuf[0]};
size_t untranslated_size = 1u + header.normal_params_size;
size_t command_size = untranslated_size + header.translate_params_size;
ASSERT(command_size <= IPC::COMMAND_BUFFER_LENGTH); // TODO(yuriks): Return error
std::copy_n(src_cmdbuf, untranslated_size, cmd_buf.begin());
size_t i = untranslated_size;
while (i < command_size) {
u32 descriptor = cmd_buf[i] = src_cmdbuf[i];
i += 1;
switch (IPC::GetDescriptorType(descriptor)) {
case IPC::DescriptorType::CopyHandle:
case IPC::DescriptorType::MoveHandle: {
u32 num_handles = IPC::HandleNumberFromDesc(descriptor);
ASSERT(i + num_handles <= command_size); // TODO(yuriks): Return error
for (u32 j = 0; j < num_handles; ++j) {
Handle handle = src_cmdbuf[i];
SharedPtr<Object> object = src_table.GetGeneric(handle);
ASSERT(object != nullptr); // TODO(yuriks): Return error
if (descriptor == IPC::DescriptorType::MoveHandle) {
src_table.Close(handle);
}
cmd_buf[i++] = AddOutgoingHandle(std::move(object));
}
break;
}
case IPC::DescriptorType::CallingPid: {
cmd_buf[i++] = src_process.process_id;
break;
}
default:
UNIMPLEMENTED_MSG("Unsupported handle translation: 0x%08X", descriptor);
}
}
return RESULT_SUCCESS;
}
ResultCode HLERequestContext::WriteToOutgoingCommandBuffer(u32_le* dst_cmdbuf, Process& dst_process,
HandleTable& dst_table) const {
IPC::Header header{cmd_buf[0]};
size_t untranslated_size = 1u + header.normal_params_size;
size_t command_size = untranslated_size + header.translate_params_size;
ASSERT(command_size <= IPC::COMMAND_BUFFER_LENGTH);
std::copy_n(cmd_buf.begin(), untranslated_size, dst_cmdbuf);
size_t i = untranslated_size;
while (i < command_size) {
u32 descriptor = dst_cmdbuf[i] = cmd_buf[i];
i += 1;
switch (IPC::GetDescriptorType(descriptor)) {
case IPC::DescriptorType::CopyHandle:
case IPC::DescriptorType::MoveHandle: {
// HLE services don't use handles, so we treat both CopyHandle and MoveHandle equally
u32 num_handles = IPC::HandleNumberFromDesc(descriptor);
ASSERT(i + num_handles <= command_size);
for (u32 j = 0; j < num_handles; ++j) {
SharedPtr<Object> object = GetIncomingHandle(cmd_buf[i]);
// TODO(yuriks): Figure out the proper error handling for if this fails
Handle handle = dst_table.Create(object).Unwrap();
dst_cmdbuf[i++] = handle;
}
break;
}
default:
UNIMPLEMENTED_MSG("Unsupported handle translation: 0x%08X", descriptor);
}
}
return RESULT_SUCCESS;
}
} // namespace Kernel

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@ -8,6 +8,7 @@
#include <memory>
#include <vector>
#include "common/common_types.h"
#include "common/swap.h"
#include "core/hle/ipc.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/server_session.h"
@ -18,6 +19,9 @@ class ServiceFrameworkBase;
namespace Kernel {
class HandleTable;
class Process;
/**
* Interface implemented by HLE Session handlers.
* This can be provided to a ServerSession in order to hook into several relevant events
@ -62,6 +66,20 @@ protected:
* Class containing information about an in-flight IPC request being handled by an HLE service
* implementation. Services should avoid using old global APIs (e.g. Kernel::GetCommandBuffer()) and
* when possible use the APIs in this class to service the request.
*
* HLE handle protocol
* ===================
*
* To avoid needing HLE services to keep a separate handle table, or having to directly modify the
* requester's table, a tweaked protocol is used to receive and send handles in requests. The kernel
* will decode the incoming handles into object pointers and insert a id in the buffer where the
* handle would normally be. The service then calls GetIncomingHandle() with that id to get the
* pointer to the object. Similarly, instead of inserting a handle into the command buffer, the
* service calls AddOutgoingHandle() and stores the returned id where the handle would normally go.
*
* The end result is similar to just giving services their own real handle tables, but since these
* ids are local to a specific context, it avoids requiring services to manage handles for objects
* across multiple calls and ensuring that unneeded handles are cleaned up.
*/
class HLERequestContext {
public:
@ -80,14 +98,29 @@ public:
return session;
}
SharedPtr<Object> GetIncomingHandle(Handle id_from_cmdbuf) const;
Handle AddOutgoingHandle(SharedPtr<Object> object);
/**
* Resolves a object id from the request command buffer into a pointer to an object. See the
* "HLE handle protocol" section in the class documentation for more details.
*/
SharedPtr<Object> GetIncomingHandle(u32 id_from_cmdbuf) const;
/**
* Adds an outgoing object to the response, returning the id which should be used to reference
* it. See the "HLE handle protocol" section in the class documentation for more details.
*/
u32 AddOutgoingHandle(SharedPtr<Object> object);
private:
friend class Service::ServiceFrameworkBase;
ResultCode PopulateFromIncomingCommandBuffer(const u32_le* src_cmdbuf, Process& src_process,
HandleTable& src_table);
ResultCode WriteToOutgoingCommandBuffer(u32_le* dst_cmdbuf, Process& dst_process,
HandleTable& dst_table) const;
std::array<u32, IPC::COMMAND_BUFFER_LENGTH> cmd_buf;
SharedPtr<ServerSession> session;
std::vector<SharedPtr<Object>> request_handles;
};
} // namespace Kernel

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@ -9,6 +9,7 @@
#include "common/string_util.h"
#include "core/hle/ipc.h"
#include "core/hle/kernel/client_port.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/server_port.h"
#include "core/hle/kernel/server_session.h"
#include "core/hle/service/ac/ac.h"
@ -172,24 +173,16 @@ void ServiceFrameworkBase::HandleSyncRequest(SharedPtr<ServerSession> server_ses
// TODO(yuriks): The kernel should be the one handling this as part of translation after
// everything else is migrated
IPC::Header request_header{cmd_buf[0]};
size_t request_size =
1 + request_header.normal_params_size + request_header.translate_params_size;
ASSERT(request_size <= IPC::COMMAND_BUFFER_LENGTH); // TODO(yuriks): Return error
Kernel::HLERequestContext context;
std::copy_n(cmd_buf, request_size, context.cmd_buf.begin());
context.session = std::move(server_session);
context.PopulateFromIncomingCommandBuffer(cmd_buf, *Kernel::g_current_process,
Kernel::g_handle_table);
LOG_TRACE(Service, "%s",
MakeFunctionString(info->name, GetServiceName().c_str(), cmd_buf).c_str());
handler_invoker(this, info->handler_callback, context);
IPC::Header response_header{context.cmd_buf[0]};
size_t response_size =
1 + response_header.normal_params_size + response_header.translate_params_size;
ASSERT(response_size <= IPC::COMMAND_BUFFER_LENGTH);
std::copy_n(context.cmd_buf.begin(), response_size, cmd_buf);
context.WriteToOutgoingCommandBuffer(cmd_buf, *Kernel::g_current_process,
Kernel::g_handle_table);
}
////////////////////////////////////////////////////////////////////////////////////////////////////