| //===-- AppleGetQueuesHandler.cpp -----------------------------------------===// | |
| // | |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | |
| // See https://llvm.org/LICENSE.txt for license information. | |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | |
| // | |
| //===----------------------------------------------------------------------===// | |
| #include "AppleGetQueuesHandler.h" | |
| #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" | |
| #include "lldb/Core/Module.h" | |
| #include "lldb/Core/Value.h" | |
| #include "lldb/Expression/DiagnosticManager.h" | |
| #include "lldb/Expression/FunctionCaller.h" | |
| #include "lldb/Expression/UtilityFunction.h" | |
| #include "lldb/Symbol/Symbol.h" | |
| #include "lldb/Target/ExecutionContext.h" | |
| #include "lldb/Target/Process.h" | |
| #include "lldb/Target/Target.h" | |
| #include "lldb/Target/Thread.h" | |
| #include "lldb/Utility/ConstString.h" | |
| #include "lldb/Utility/LLDBLog.h" | |
| #include "lldb/Utility/Log.h" | |
| #include "lldb/Utility/StreamString.h" | |
| using namespace lldb; | |
| using namespace lldb_private; | |
| const char *AppleGetQueuesHandler::g_get_current_queues_function_name = | |
| "__lldb_backtrace_recording_get_current_queues"; | |
| const char *AppleGetQueuesHandler::g_get_current_queues_function_code = | |
| " \n\ | |
| extern \"C\" \n\ | |
| { \n\ | |
| /* \n\ | |
| * mach defines \n\ | |
| */ \n\ | |
| \n\ | |
| typedef unsigned int uint32_t; \n\ | |
| typedef unsigned long long uint64_t; \n\ | |
| typedef uint32_t mach_port_t; \n\ | |
| typedef mach_port_t vm_map_t; \n\ | |
| typedef int kern_return_t; \n\ | |
| typedef uint64_t mach_vm_address_t; \n\ | |
| typedef uint64_t mach_vm_size_t; \n\ | |
| \n\ | |
| mach_port_t mach_task_self (); \n\ | |
| kern_return_t mach_vm_deallocate (vm_map_t target, mach_vm_address_t address, mach_vm_size_t size); \n\ | |
| \n\ | |
| /* \n\ | |
| * libBacktraceRecording defines \n\ | |
| */ \n\ | |
| \n\ | |
| typedef uint32_t queue_list_scope_t; \n\ | |
| typedef void *introspection_dispatch_queue_info_t; \n\ | |
| \n\ | |
| extern uint64_t __introspection_dispatch_get_queues (queue_list_scope_t scope, \n\ | |
| introspection_dispatch_queue_info_t *returned_queues_buffer, \n\ | |
| uint64_t *returned_queues_buffer_size); \n\ | |
| extern int printf(const char *format, ...); \n\ | |
| \n\ | |
| /* \n\ | |
| * return type define \n\ | |
| */ \n\ | |
| \n\ | |
| struct get_current_queues_return_values \n\ | |
| { \n\ | |
| uint64_t queues_buffer_ptr; /* the address of the queues buffer from libBacktraceRecording */ \n\ | |
| uint64_t queues_buffer_size; /* the size of the queues buffer from libBacktraceRecording */ \n\ | |
| uint64_t count; /* the number of queues included in the queues buffer */ \n\ | |
| }; \n\ | |
| \n\ | |
| void __lldb_backtrace_recording_get_current_queues \n\ | |
| (struct get_current_queues_return_values *return_buffer, \n\ | |
| int debug, \n\ | |
| void *page_to_free, \n\ | |
| uint64_t page_to_free_size) \n\ | |
| { \n\ | |
| if (debug) \n\ | |
| printf (\"entering get_current_queues with args %p, %d, 0x%p, 0x%llx\\n\", return_buffer, debug, page_to_free, page_to_free_size); \n\ | |
| if (page_to_free != 0) \n\ | |
| { \n\ | |
| mach_vm_deallocate (mach_task_self(), (mach_vm_address_t) page_to_free, (mach_vm_size_t) page_to_free_size); \n\ | |
| } \n\ | |
| \n\ | |
| return_buffer->count = __introspection_dispatch_get_queues ( \n\ | |
| /* QUEUES_WITH_ANY_ITEMS */ 2, \n\ | |
| (void**)&return_buffer->queues_buffer_ptr, \n\ | |
| &return_buffer->queues_buffer_size); \n\ | |
| if (debug) \n\ | |
| printf(\"result was count %lld\\n\", return_buffer->count); \n\ | |
| } \n\ | |
| } \n\ | |
| "; | |
| AppleGetQueuesHandler::AppleGetQueuesHandler(Process *process) | |
| : m_process(process), m_get_queues_impl_code_up(), | |
| m_get_queues_function_mutex(), | |
| m_get_queues_return_buffer_addr(LLDB_INVALID_ADDRESS), | |
| m_get_queues_retbuffer_mutex() {} | |
| AppleGetQueuesHandler::~AppleGetQueuesHandler() = default; | |
| void AppleGetQueuesHandler::Detach() { | |
| if (m_process && m_process->IsAlive() && | |
| m_get_queues_return_buffer_addr != LLDB_INVALID_ADDRESS) { | |
| std::unique_lock<std::mutex> lock(m_get_queues_retbuffer_mutex, | |
| std::defer_lock); | |
| (void)lock.try_lock(); // Even if we don't get the lock, deallocate the buffer | |
| m_process->DeallocateMemory(m_get_queues_return_buffer_addr); | |
| } | |
| } | |
| // Construct a CompilerType for the structure that | |
| // g_get_current_queues_function_code will return by value so we can extract | |
| // the fields after performing the function call. i.e. we are getting this | |
| // struct returned to us: | |
| // | |
| // struct get_current_queues_return_values | |
| // { | |
| // introspection_dispatch_queue_info_t *queues_buffer; | |
| // uint64_t queues_buffer_size; | |
| // uint64_t count; | |
| // }; | |
| // Compile our __lldb_backtrace_recording_get_current_queues() function (from | |
| // the source above in g_get_current_queues_function_code) if we don't find | |
| // that function in the inferior already with USE_BUILTIN_FUNCTION defined. | |
| // (e.g. this would be the case for testing.) | |
| // | |
| // Insert the __lldb_backtrace_recording_get_current_queues into the inferior | |
| // process if needed. | |
| // | |
| // Write the get_queues_arglist into the inferior's memory space to prepare for | |
| // the call. | |
| // | |
| // Returns the address of the arguments written down in the inferior process, | |
| // which can be used to make the function call. | |
| lldb::addr_t | |
| AppleGetQueuesHandler::SetupGetQueuesFunction(Thread &thread, | |
| ValueList &get_queues_arglist) { | |
| ThreadSP thread_sp(thread.shared_from_this()); | |
| ExecutionContext exe_ctx(thread_sp); | |
| Address impl_code_address; | |
| DiagnosticManager diagnostics; | |
| Log *log = GetLog(LLDBLog::SystemRuntime); | |
| lldb::addr_t args_addr = LLDB_INVALID_ADDRESS; | |
| FunctionCaller *get_queues_caller = nullptr; | |
| // Scope for mutex locker: | |
| { | |
| std::lock_guard<std::mutex> guard(m_get_queues_function_mutex); | |
| // First stage is to make the ClangUtility to hold our injected function: | |
| if (!m_get_queues_impl_code_up) { | |
| if (g_get_current_queues_function_code != nullptr) { | |
| auto utility_fn_or_error = exe_ctx.GetTargetRef().CreateUtilityFunction( | |
| g_get_current_queues_function_code, | |
| g_get_current_queues_function_name, eLanguageTypeC, exe_ctx); | |
| if (!utility_fn_or_error) { | |
| LLDB_LOG_ERROR(log, utility_fn_or_error.takeError(), | |
| "Failed to create UtilityFunction for queues " | |
| "introspection: {0}."); | |
| return args_addr; | |
| } | |
| m_get_queues_impl_code_up = std::move(*utility_fn_or_error); | |
| } else { | |
| if (log) { | |
| LLDB_LOGF(log, "No queues introspection code found."); | |
| diagnostics.Dump(log); | |
| } | |
| return LLDB_INVALID_ADDRESS; | |
| } | |
| } | |
| // Next make the runner function for our implementation utility function. | |
| TypeSystemClangSP scratch_ts_sp = | |
| ScratchTypeSystemClang::GetForTarget(thread.GetProcess()->GetTarget()); | |
| CompilerType get_queues_return_type = | |
| scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); | |
| Status error; | |
| get_queues_caller = m_get_queues_impl_code_up->MakeFunctionCaller( | |
| get_queues_return_type, get_queues_arglist, thread_sp, error); | |
| if (error.Fail() || get_queues_caller == nullptr) { | |
| LLDB_LOGF(log, | |
| "Could not get function caller for get-queues function: %s.", | |
| error.AsCString()); | |
| return args_addr; | |
| } | |
| } | |
| diagnostics.Clear(); | |
| // Now write down the argument values for this particular call. This looks | |
| // like it might be a race condition if other threads were calling into here, | |
| // but actually it isn't because we allocate a new args structure for this | |
| // call by passing args_addr = LLDB_INVALID_ADDRESS... | |
| if (!get_queues_caller->WriteFunctionArguments( | |
| exe_ctx, args_addr, get_queues_arglist, diagnostics)) { | |
| if (log) { | |
| LLDB_LOGF(log, "Error writing get-queues function arguments."); | |
| diagnostics.Dump(log); | |
| } | |
| return args_addr; | |
| } | |
| return args_addr; | |
| } | |
| AppleGetQueuesHandler::GetQueuesReturnInfo | |
| AppleGetQueuesHandler::GetCurrentQueues(Thread &thread, addr_t page_to_free, | |
| uint64_t page_to_free_size, | |
| Status &error) { | |
| lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0); | |
| ProcessSP process_sp(thread.CalculateProcess()); | |
| TargetSP target_sp(thread.CalculateTarget()); | |
| TypeSystemClangSP scratch_ts_sp = | |
| ScratchTypeSystemClang::GetForTarget(*target_sp); | |
| Log *log = GetLog(LLDBLog::SystemRuntime); | |
| GetQueuesReturnInfo return_value; | |
| return_value.queues_buffer_ptr = LLDB_INVALID_ADDRESS; | |
| return_value.queues_buffer_size = 0; | |
| return_value.count = 0; | |
| error.Clear(); | |
| if (!thread.SafeToCallFunctions()) { | |
| LLDB_LOGF(log, "Not safe to call functions on thread 0x%" PRIx64, | |
| thread.GetID()); | |
| error = | |
| Status::FromErrorString("Not safe to call functions on this thread."); | |
| return return_value; | |
| } | |
| // Set up the arguments for a call to | |
| // struct get_current_queues_return_values | |
| // { | |
| // uint64_t queues_buffer_ptr; /* the address of the queues buffer from | |
| // libBacktraceRecording */ | |
| // uint64_t queues_buffer_size; /* the size of the queues buffer from | |
| // libBacktraceRecording */ | |
| // uint64_t count; /* the number of queues included in the | |
| // queues buffer */ | |
| // }; | |
| // | |
| // void | |
| // __lldb_backtrace_recording_get_current_queues | |
| // (struct | |
| // get_current_queues_return_values | |
| // *return_buffer, | |
| // void *page_to_free, | |
| // uint64_t page_to_free_size); | |
| // Where the return_buffer argument points to a 24 byte region of memory | |
| // already allocated by lldb in the inferior process. | |
| CompilerType clang_void_ptr_type = | |
| scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); | |
| Value return_buffer_ptr_value; | |
| return_buffer_ptr_value.SetValueType(Value::ValueType::Scalar); | |
| return_buffer_ptr_value.SetCompilerType(clang_void_ptr_type); | |
| CompilerType clang_int_type = scratch_ts_sp->GetBasicType(eBasicTypeInt); | |
| Value debug_value; | |
| debug_value.SetValueType(Value::ValueType::Scalar); | |
| debug_value.SetCompilerType(clang_int_type); | |
| Value page_to_free_value; | |
| page_to_free_value.SetValueType(Value::ValueType::Scalar); | |
| page_to_free_value.SetCompilerType(clang_void_ptr_type); | |
| CompilerType clang_uint64_type = | |
| scratch_ts_sp->GetBasicType(eBasicTypeUnsignedLongLong); | |
| Value page_to_free_size_value; | |
| page_to_free_size_value.SetValueType(Value::ValueType::Scalar); | |
| page_to_free_size_value.SetCompilerType(clang_uint64_type); | |
| std::lock_guard<std::mutex> guard(m_get_queues_retbuffer_mutex); | |
| if (m_get_queues_return_buffer_addr == LLDB_INVALID_ADDRESS) { | |
| addr_t bufaddr = process_sp->AllocateMemory( | |
| 32, ePermissionsReadable | ePermissionsWritable, error); | |
| if (!error.Success() || bufaddr == LLDB_INVALID_ADDRESS) { | |
| LLDB_LOGF(log, "Failed to allocate memory for return buffer for get " | |
| "current queues func call"); | |
| return return_value; | |
| } | |
| m_get_queues_return_buffer_addr = bufaddr; | |
| } | |
| ValueList argument_values; | |
| return_buffer_ptr_value.GetScalar() = m_get_queues_return_buffer_addr; | |
| argument_values.PushValue(return_buffer_ptr_value); | |
| debug_value.GetScalar() = 0; | |
| argument_values.PushValue(debug_value); | |
| if (page_to_free != LLDB_INVALID_ADDRESS) | |
| page_to_free_value.GetScalar() = page_to_free; | |
| else | |
| page_to_free_value.GetScalar() = 0; | |
| argument_values.PushValue(page_to_free_value); | |
| page_to_free_size_value.GetScalar() = page_to_free_size; | |
| argument_values.PushValue(page_to_free_size_value); | |
| addr_t args_addr = SetupGetQueuesFunction(thread, argument_values); | |
| if (!m_get_queues_impl_code_up) { | |
| error = Status::FromErrorString( | |
| "Unable to compile __introspection_dispatch_get_queues."); | |
| return return_value; | |
| } | |
| FunctionCaller *get_queues_caller = | |
| m_get_queues_impl_code_up->GetFunctionCaller(); | |
| if (get_queues_caller == nullptr) { | |
| error = Status::FromErrorString( | |
| "Unable to get caller for call __introspection_dispatch_get_queues"); | |
| return return_value; | |
| } | |
| DiagnosticManager diagnostics; | |
| ExecutionContext exe_ctx; | |
| EvaluateExpressionOptions options; | |
| options.SetUnwindOnError(true); | |
| options.SetIgnoreBreakpoints(true); | |
| options.SetStopOthers(true); | |
| #if __has_feature(address_sanitizer) | |
| options.SetTimeout(process_sp->GetUtilityExpressionTimeout()); | |
| #else | |
| options.SetTimeout(std::chrono::milliseconds(500)); | |
| #endif | |
| options.SetTryAllThreads(false); | |
| options.SetIsForUtilityExpr(true); | |
| thread.CalculateExecutionContext(exe_ctx); | |
| ExpressionResults func_call_ret; | |
| Value results; | |
| func_call_ret = get_queues_caller->ExecuteFunction( | |
| exe_ctx, &args_addr, options, diagnostics, results); | |
| if (func_call_ret != eExpressionCompleted || !error.Success()) { | |
| LLDB_LOGF(log, | |
| "Unable to call introspection_get_dispatch_queues(), got " | |
| "ExpressionResults %d, error contains %s", | |
| func_call_ret, error.AsCString("")); | |
| error = Status::FromErrorString( | |
| "Unable to call introspection_get_dispatch_queues() " | |
| "for list of queues"); | |
| return return_value; | |
| } | |
| return_value.queues_buffer_ptr = m_process->ReadUnsignedIntegerFromMemory( | |
| m_get_queues_return_buffer_addr, 8, LLDB_INVALID_ADDRESS, error); | |
| if (!error.Success() || | |
| return_value.queues_buffer_ptr == LLDB_INVALID_ADDRESS) { | |
| return_value.queues_buffer_ptr = LLDB_INVALID_ADDRESS; | |
| return return_value; | |
| } | |
| return_value.queues_buffer_size = m_process->ReadUnsignedIntegerFromMemory( | |
| m_get_queues_return_buffer_addr + 8, 8, 0, error); | |
| if (!error.Success()) { | |
| return_value.queues_buffer_ptr = LLDB_INVALID_ADDRESS; | |
| return return_value; | |
| } | |
| return_value.count = m_process->ReadUnsignedIntegerFromMemory( | |
| m_get_queues_return_buffer_addr + 16, 8, 0, error); | |
| if (!error.Success()) { | |
| return_value.queues_buffer_ptr = LLDB_INVALID_ADDRESS; | |
| return return_value; | |
| } | |
| LLDB_LOGF(log, | |
| "AppleGetQueuesHandler called " | |
| "__introspection_dispatch_get_queues (page_to_free == " | |
| "0x%" PRIx64 ", size = %" PRId64 "), returned page is at 0x%" PRIx64 | |
| ", size %" PRId64 ", count = %" PRId64, | |
| page_to_free, page_to_free_size, return_value.queues_buffer_ptr, | |
| return_value.queues_buffer_size, return_value.count); | |
| return return_value; | |
| } |