// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <bitset>
#include <memory>
#include <random>
#include "common/alignment.h"
#include "common/assert.h"
#include "common/logging/log.h"
#include "core/core.h"
#include "core/file_sys/program_metadata.h"
#include "core/hle/kernel/code_set.h"
#include "core/hle/kernel/errors.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/resource_limit.h"
#include "core/hle/kernel/scheduler.h"
#include "core/hle/kernel/thread.h"
#include "core/hle/kernel/vm_manager.h"
#include "core/memory.h"
#include "core/settings.h"
namespace Kernel {
namespace {
/**
* Sets up the primary application thread
*
* @param owner_process The parent process for the main thread
* @param kernel The kernel instance to create the main thread under.
* @param priority The priority to give the main thread
*/
void SetupMainThread(Process& owner_process, KernelCore& kernel, u32 priority) {
const auto& vm_manager = owner_process.VMManager();
const VAddr entry_point = vm_manager.GetCodeRegionBaseAddress();
const VAddr stack_top = vm_manager.GetTLSIORegionEndAddress();
auto thread_res = Thread::Create(kernel, "main", entry_point, priority, 0,
owner_process.GetIdealCore(), stack_top, owner_process);
SharedPtr<Thread> thread = std::move(thread_res).Unwrap();
// Register 1 must be a handle to the main thread
const Handle thread_handle = owner_process.GetHandleTable().Create(thread).Unwrap();
thread->GetContext().cpu_registers[1] = thread_handle;
// Threads by default are dormant, wake up the main thread so it runs when the scheduler fires
thread->ResumeFromWait();
}
} // Anonymous namespace
// Represents a page used for thread-local storage.
//
// Each TLS page contains slots that may be used by processes and threads.
// Every process and thread is created with a slot in some arbitrary page
// (whichever page happens to have an available slot).
class TLSPage {
public:
static constexpr std::size_t num_slot_entries = Memory::PAGE_SIZE / Memory::TLS_ENTRY_SIZE;
explicit TLSPage(VAddr address) : base_address{address} {}
bool HasAvailableSlots() const {
return !is_slot_used.all();
}
VAddr GetBaseAddress() const {
return base_address;
}
std::optional<VAddr> ReserveSlot() {
for (std::size_t i = 0; i < is_slot_used.size(); i++) {
if (is_slot_used[i]) {
continue;
}
is_slot_used[i] = true;
return base_address + (i * Memory::TLS_ENTRY_SIZE);
}
return std::nullopt;
}
void ReleaseSlot(VAddr address) {
// Ensure that all given addresses are consistent with how TLS pages
// are intended to be used when releasing slots.
ASSERT(IsWithinPage(address));
ASSERT((address % Memory::TLS_ENTRY_SIZE) == 0);
const std::size_t index = (address - base_address) / Memory::TLS_ENTRY_SIZE;
is_slot_used[index] = false;
}
private:
bool IsWithinPage(VAddr address) const {
return base_address <= address && address < base_address + Memory::PAGE_SIZE;
}
VAddr base_address;
std::bitset<num_slot_entries> is_slot_used;
};
SharedPtr<Process> Process::Create(Core::System& system, std::string name, ProcessType type) {
auto& kernel = system.Kernel();
SharedPtr<Process> process(new Process(system));
process->name = std::move(name);
process->resource_limit = kernel.GetSystemResourceLimit();
process->status = ProcessStatus::Created;
process->program_id = 0;
process->process_id = type == ProcessType::KernelInternal ? kernel.CreateNewKernelProcessID()
: kernel.CreateNewUserProcessID();
process->capabilities.InitializeForMetadatalessProcess();
std::mt19937 rng(Settings::values.rng_seed.value_or(0));
std::uniform_int_distribution<u64> distribution;
std::generate(process->random_entropy.begin(), process->random_entropy.end(),
[&] { return distribution(rng); });
kernel.AppendNewProcess(process);
return process;
}
SharedPtr<ResourceLimit> Process::GetResourceLimit() const {
return resource_limit;
}
u64 Process::GetTotalPhysicalMemoryAvailable() const {
return vm_manager.GetTotalPhysicalMemoryAvailable();
}
u64 Process::GetTotalPhysicalMemoryAvailableWithoutMmHeap() const {
// TODO: Subtract the personal heap size from this when the
// personal heap is implemented.
return GetTotalPhysicalMemoryAvailable();
}
u64 Process::GetTotalPhysicalMemoryUsed() const {
return vm_manager.GetCurrentHeapSize() + main_thread_stack_size + code_memory_size;
}
u64 Process::GetTotalPhysicalMemoryUsedWithoutMmHeap() const {
// TODO: Subtract the personal heap size from this when the
// personal heap is implemented.
return GetTotalPhysicalMemoryUsed();
}
void Process::RegisterThread(const Thread* thread) {
thread_list.push_back(thread);
}
void Process::UnregisterThread(const Thread* thread) {
thread_list.remove(thread);
}
ResultCode Process::ClearSignalState() {
if (status == ProcessStatus::Exited) {
LOG_ERROR(Kernel, "called on a terminated process instance.");
return ERR_INVALID_STATE;
}
if (!is_signaled) {
LOG_ERROR(Kernel, "called on a process instance that isn't signaled.");
return ERR_INVALID_STATE;
}
is_signaled = false;
return RESULT_SUCCESS;
}
ResultCode Process::LoadFromMetadata(const FileSys::ProgramMetadata& metadata) {
program_id = metadata.GetTitleID();
ideal_core = metadata.GetMainThreadCore();
is_64bit_process = metadata.Is64BitProgram();
vm_manager.Reset(metadata.GetAddressSpaceType());
const auto& caps = metadata.GetKernelCapabilities();
const auto capability_init_result =
capabilities.InitializeForUserProcess(caps.data(), caps.size(), vm_manager);
if (capability_init_result.IsError()) {
return capability_init_result;
}
return handle_table.SetSize(capabilities.GetHandleTableSize());
}
void Process::Run(s32 main_thread_priority, u64 stack_size) {
AllocateMainThreadStack(stack_size);
tls_region_address = CreateTLSRegion();
vm_manager.LogLayout();
ChangeStatus(ProcessStatus::Running);
SetupMainThread(*this, kernel, main_thread_priority);
}
void Process::PrepareForTermination() {
ChangeStatus(ProcessStatus::Exiting);
const auto stop_threads = [this](const std::vector<SharedPtr<Thread>>& thread_list) {
for (auto& thread : thread_list) {
if (thread->GetOwnerProcess() != this)
continue;
if (thread == system.CurrentScheduler().GetCurrentThread())
continue;
// TODO(Subv): When are the other running/ready threads terminated?
ASSERT_MSG(thread->GetStatus() == ThreadStatus::WaitSynch,
"Exiting processes with non-waiting threads is currently unimplemented");
thread->Stop();
}
};
stop_threads(system.Scheduler(0).GetThreadList());
stop_threads(system.Scheduler(1).GetThreadList());
stop_threads(system.Scheduler(2).GetThreadList());
stop_threads(system.Scheduler(3).GetThreadList());
FreeTLSRegion(tls_region_address);
tls_region_address = 0;
ChangeStatus(ProcessStatus::Exited);
}
/**
* Attempts to find a TLS page that contains a free slot for
* use by a thread.
*
* @returns If a page with an available slot is found, then an iterator
* pointing to the page is returned. Otherwise the end iterator
* is returned instead.
*/
static auto FindTLSPageWithAvailableSlots(std::vector<TLSPage>& tls_pages) {
return std::find_if(tls_pages.begin(), tls_pages.end(),
[](const auto& page) { return page.HasAvailableSlots(); });
}
VAddr Process::CreateTLSRegion() {
auto tls_page_iter = FindTLSPageWithAvailableSlots(tls_pages);
if (tls_page_iter == tls_pages.cend()) {
const auto region_address =
vm_manager.FindFreeRegion(vm_manager.GetTLSIORegionBaseAddress(),
vm_manager.GetTLSIORegionEndAddress(), Memory::PAGE_SIZE);
ASSERT(region_address.Succeeded());
const auto map_result = vm_manager.MapMemoryBlock(
*region_address, std::make_shared<std::vector<u8>>(Memory::PAGE_SIZE), 0,
Memory::PAGE_SIZE, MemoryState::ThreadLocal);
ASSERT(map_result.Succeeded());
tls_pages.emplace_back(*region_address);
const auto reserve_result = tls_pages.back().ReserveSlot();
ASSERT(reserve_result.has_value());
return *reserve_result;
}
return *tls_page_iter->ReserveSlot();
}
void Process::FreeTLSRegion(VAddr tls_address) {
const VAddr aligned_address = Common::AlignDown(tls_address, Memory::PAGE_SIZE);
auto iter =
std::find_if(tls_pages.begin(), tls_pages.end(), [aligned_address](const auto& page) {
return page.GetBaseAddress() == aligned_address;
});
// Something has gone very wrong if we're freeing a region
// with no actual page available.
ASSERT(iter != tls_pages.cend());
iter->ReleaseSlot(tls_address);
}
void Process::LoadModule(CodeSet module_, VAddr base_addr) {
const auto memory = std::make_shared<std::vector<u8>>(std::move(module_.memory));
const auto MapSegment = [&](const CodeSet::Segment& segment, VMAPermission permissions,
MemoryState memory_state) {
const auto vma = vm_manager
.MapMemoryBlock(segment.addr + base_addr, memory, segment.offset,
segment.size, memory_state)
.Unwrap();
vm_manager.Reprotect(vma, permissions);
};
// Map CodeSet segments
MapSegment(module_.CodeSegment(), VMAPermission::ReadExecute, MemoryState::Code);
MapSegment(module_.RODataSegment(), VMAPermission::Read, MemoryState::CodeData);
MapSegment(module_.DataSegment(), VMAPermission::ReadWrite, MemoryState::CodeData);
code_memory_size += module_.memory.size();
}
Process::Process(Core::System& system)
: WaitObject{system.Kernel()}, vm_manager{system},
address_arbiter{system}, mutex{system}, system{system} {}
Process::~Process() = default;
void Process::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "Object unavailable!");
}
bool Process::ShouldWait(const Thread* thread) const {
return !is_signaled;
}
void Process::ChangeStatus(ProcessStatus new_status) {
if (status == new_status) {
return;
}
status = new_status;
is_signaled = true;
WakeupAllWaitingThreads();
}
void Process::AllocateMainThreadStack(u64 stack_size) {
// The kernel always ensures that the given stack size is page aligned.
main_thread_stack_size = Common::AlignUp(stack_size, Memory::PAGE_SIZE);
// Allocate and map the main thread stack
const VAddr mapping_address = vm_manager.GetTLSIORegionEndAddress() - main_thread_stack_size;
vm_manager
.MapMemoryBlock(mapping_address, std::make_shared<std::vector<u8>>(main_thread_stack_size),
0, main_thread_stack_size, MemoryState::Stack)
.Unwrap();
}
} // namespace Kernel