summaryrefslogtreecommitdiffstats
path: root/src/core/hle/kernel/process.cpp
blob: 47b3ac57b3fb47b180febe9fd09f543b8c28420e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <algorithm>
#include <bitset>
#include <ctime>
#include <memory>
#include <random>
#include "common/alignment.h"
#include "common/assert.h"
#include "common/logging/log.h"
#include "core/core.h"
#include "core/device_memory.h"
#include "core/file_sys/program_metadata.h"
#include "core/hle/kernel/code_set.h"
#include "core/hle/kernel/k_resource_limit.h"
#include "core/hle/kernel/k_scheduler.h"
#include "core/hle/kernel/k_scoped_resource_reservation.h"
#include "core/hle/kernel/k_thread.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/memory/memory_block_manager.h"
#include "core/hle/kernel/memory/page_table.h"
#include "core/hle/kernel/memory/slab_heap.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/svc_results.h"
#include "core/hle/lock.h"
#include "core/memory.h"
#include "core/settings.h"

namespace Kernel {
namespace {
/**
 * Sets up the primary application thread
 *
 * @param system The system instance to create the main thread under.
 * @param owner_process The parent process for the main thread
 * @param priority The priority to give the main thread
 */
void SetupMainThread(Core::System& system, Process& owner_process, u32 priority, VAddr stack_top) {
    const VAddr entry_point = owner_process.PageTable().GetCodeRegionStart();
    ASSERT(owner_process.GetResourceLimit()->Reserve(LimitableResource::Threads, 1));
    auto thread_res = KThread::Create(system, ThreadType::User, "main", entry_point, priority, 0,
                                      owner_process.GetIdealCoreId(), stack_top, &owner_process);

    std::shared_ptr<KThread> 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->GetContext32().cpu_registers[0] = 0;
    thread->GetContext64().cpu_registers[0] = 0;
    thread->GetContext32().cpu_registers[1] = thread_handle;
    thread->GetContext64().cpu_registers[1] = thread_handle;

    auto& kernel = system.Kernel();
    // Threads by default are dormant, wake up the main thread so it runs when the scheduler fires
    {
        KScopedSchedulerLock lock{kernel};
        thread->SetState(ThreadState::Runnable);
    }
}
} // 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 =
        Core::Memory::PAGE_SIZE / Core::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 * Core::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 % Core::Memory::TLS_ENTRY_SIZE) == 0);

        const std::size_t index = (address - base_address) / Core::Memory::TLS_ENTRY_SIZE;
        is_slot_used[index] = false;
    }

private:
    bool IsWithinPage(VAddr address) const {
        return base_address <= address && address < base_address + Core::Memory::PAGE_SIZE;
    }

    VAddr base_address;
    std::bitset<num_slot_entries> is_slot_used;
};

std::shared_ptr<Process> Process::Create(Core::System& system, std::string name, ProcessType type) {
    auto& kernel = system.Kernel();

    std::shared_ptr<Process> process = std::make_shared<Process>(system);
    process->name = std::move(name);

    // TODO: This is inaccurate
    // The process should hold a reference to the kernel-wide resource limit.
    process->resource_limit = std::make_shared<KResourceLimit>(kernel, system);
    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.GetValue().value_or(std::time(nullptr)));
    std::uniform_int_distribution<u64> distribution;
    std::generate(process->random_entropy.begin(), process->random_entropy.end(),
                  [&] { return distribution(rng); });

    kernel.AppendNewProcess(process);
    return process;
}

std::shared_ptr<KResourceLimit> Process::GetResourceLimit() const {
    return resource_limit;
}

void Process::IncrementThreadCount() {
    ASSERT(num_threads >= 0);
    num_created_threads++;

    if (const auto count = ++num_threads; count > peak_num_threads) {
        peak_num_threads = count;
    }
}

void Process::DecrementThreadCount() {
    ASSERT(num_threads > 0);

    if (const auto count = --num_threads; count == 0) {
        UNIMPLEMENTED_MSG("Process termination is not implemented!");
    }
}

u64 Process::GetTotalPhysicalMemoryAvailable() const {
    // TODO: This is expected to always return the application memory pool size after accurately
    // reserving kernel resources. The current workaround uses a process-local resource limit of
    // application memory pool size, which is inaccurate.
    const u64 capacity{resource_limit->GetFreeValue(LimitableResource::PhysicalMemory) +
                       page_table->GetTotalHeapSize() + GetSystemResourceSize() + image_size +
                       main_thread_stack_size};

    if (capacity < memory_usage_capacity) {
        return capacity;
    }

    return memory_usage_capacity;
}

u64 Process::GetTotalPhysicalMemoryAvailableWithoutSystemResource() const {
    return GetTotalPhysicalMemoryAvailable() - GetSystemResourceSize();
}

u64 Process::GetTotalPhysicalMemoryUsed() const {
    return image_size + main_thread_stack_size + page_table->GetTotalHeapSize() +
           GetSystemResourceSize();
}

u64 Process::GetTotalPhysicalMemoryUsedWithoutSystemResource() const {
    return GetTotalPhysicalMemoryUsed() - GetSystemResourceUsage();
}

bool Process::ReleaseUserException(KThread* thread) {
    KScopedSchedulerLock sl{kernel};

    if (exception_thread == thread) {
        exception_thread = nullptr;

        // Remove waiter thread.
        s32 num_waiters{};
        KThread* next = thread->RemoveWaiterByKey(
            std::addressof(num_waiters),
            reinterpret_cast<uintptr_t>(std::addressof(exception_thread)));
        if (next != nullptr) {
            if (next->GetState() == ThreadState::Waiting) {
                next->SetState(ThreadState::Runnable);
            } else {
                KScheduler::SetSchedulerUpdateNeeded(kernel);
            }
        }

        return true;
    } else {
        return false;
    }
}

void Process::PinCurrentThread() {
    ASSERT(kernel.GlobalSchedulerContext().IsLocked());

    // Get the current thread.
    const s32 core_id = GetCurrentCoreId(kernel);
    KThread* cur_thread = GetCurrentThreadPointer(kernel);

    // Pin it.
    PinThread(core_id, cur_thread);
    cur_thread->Pin();

    // An update is needed.
    KScheduler::SetSchedulerUpdateNeeded(kernel);
}

void Process::UnpinCurrentThread() {
    ASSERT(kernel.GlobalSchedulerContext().IsLocked());

    // Get the current thread.
    const s32 core_id = GetCurrentCoreId(kernel);
    KThread* cur_thread = GetCurrentThreadPointer(kernel);

    // Unpin it.
    cur_thread->Unpin();
    UnpinThread(core_id, cur_thread);

    // An update is needed.
    KScheduler::SetSchedulerUpdateNeeded(kernel);
}

void Process::RegisterThread(const KThread* thread) {
    thread_list.push_back(thread);
}

void Process::UnregisterThread(const KThread* thread) {
    thread_list.remove(thread);
}

ResultCode Process::Reset() {
    // Lock the process and the scheduler.
    KScopedLightLock lk(state_lock);
    KScopedSchedulerLock sl{kernel};

    // Validate that we're in a state that we can reset.
    R_UNLESS(status != ProcessStatus::Exited, ResultInvalidState);
    R_UNLESS(is_signaled, ResultInvalidState);

    // Clear signaled.
    is_signaled = false;
    return RESULT_SUCCESS;
}

ResultCode Process::LoadFromMetadata(const FileSys::ProgramMetadata& metadata,
                                     std::size_t code_size) {
    program_id = metadata.GetTitleID();
    ideal_core = metadata.GetMainThreadCore();
    is_64bit_process = metadata.Is64BitProgram();
    system_resource_size = metadata.GetSystemResourceSize();
    image_size = code_size;

    // Set initial resource limits
    resource_limit->SetLimitValue(
        LimitableResource::PhysicalMemory,
        kernel.MemoryManager().GetSize(Memory::MemoryManager::Pool::Application));
    KScopedResourceReservation memory_reservation(resource_limit, LimitableResource::PhysicalMemory,
                                                  code_size + system_resource_size);
    if (!memory_reservation.Succeeded()) {
        LOG_ERROR(Kernel, "Could not reserve process memory requirements of size {:X} bytes",
                  code_size + system_resource_size);
        return ResultResourceLimitedExceeded;
    }
    // Initialize proces address space
    if (const ResultCode result{
            page_table->InitializeForProcess(metadata.GetAddressSpaceType(), false, 0x8000000,
                                             code_size, Memory::MemoryManager::Pool::Application)};
        result.IsError()) {
        return result;
    }

    // Map process code region
    if (const ResultCode result{page_table->MapProcessCode(
            page_table->GetCodeRegionStart(), code_size / Memory::PageSize,
            Memory::MemoryState::Code, Memory::MemoryPermission::None)};
        result.IsError()) {
        return result;
    }

    // Initialize process capabilities
    const auto& caps{metadata.GetKernelCapabilities()};
    if (const ResultCode result{
            capabilities.InitializeForUserProcess(caps.data(), caps.size(), *page_table)};
        result.IsError()) {
        return result;
    }

    // Set memory usage capacity
    switch (metadata.GetAddressSpaceType()) {
    case FileSys::ProgramAddressSpaceType::Is32Bit:
    case FileSys::ProgramAddressSpaceType::Is36Bit:
    case FileSys::ProgramAddressSpaceType::Is39Bit:
        memory_usage_capacity = page_table->GetHeapRegionEnd() - page_table->GetHeapRegionStart();
        break;

    case FileSys::ProgramAddressSpaceType::Is32BitNoMap:
        memory_usage_capacity = page_table->GetHeapRegionEnd() - page_table->GetHeapRegionStart() +
                                page_table->GetAliasRegionEnd() - page_table->GetAliasRegionStart();
        break;

    default:
        UNREACHABLE();
    }

    resource_limit->SetLimitValue(LimitableResource::Threads, 608);
    resource_limit->SetLimitValue(LimitableResource::Events, 700);
    resource_limit->SetLimitValue(LimitableResource::TransferMemory, 128);
    resource_limit->SetLimitValue(LimitableResource::Sessions, 894);

    // Create TLS region
    tls_region_address = CreateTLSRegion();
    memory_reservation.Commit();

    return handle_table.SetSize(capabilities.GetHandleTableSize());
}

void Process::Run(s32 main_thread_priority, u64 stack_size) {
    AllocateMainThreadStack(stack_size);
    resource_limit->Reserve(LimitableResource::Threads, 1);
    resource_limit->Reserve(LimitableResource::PhysicalMemory, main_thread_stack_size);

    const std::size_t heap_capacity{memory_usage_capacity - main_thread_stack_size - image_size};
    ASSERT(!page_table->SetHeapCapacity(heap_capacity).IsError());

    ChangeStatus(ProcessStatus::Running);

    SetupMainThread(system, *this, main_thread_priority, main_thread_stack_top);
}

void Process::PrepareForTermination() {
    ChangeStatus(ProcessStatus::Exiting);

    const auto stop_threads = [this](const std::vector<std::shared_ptr<KThread>>& thread_list) {
        for (auto& thread : thread_list) {
            if (thread->GetOwnerProcess() != this)
                continue;

            if (thread.get() == kernel.CurrentScheduler()->GetCurrentThread())
                continue;

            // TODO(Subv): When are the other running/ready threads terminated?
            ASSERT_MSG(thread->GetState() == ThreadState::Waiting,
                       "Exiting processes with non-waiting threads is currently unimplemented");

            thread->Exit();
        }
    };

    stop_threads(system.GlobalSchedulerContext().GetThreadList());

    FreeTLSRegion(tls_region_address);
    tls_region_address = 0;

    if (resource_limit) {
        resource_limit->Release(LimitableResource::PhysicalMemory,
                                main_thread_stack_size + image_size);
    }

    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() {
    KScopedSchedulerLock lock(system.Kernel());
    if (auto tls_page_iter{FindTLSPageWithAvailableSlots(tls_pages)};
        tls_page_iter != tls_pages.cend()) {
        return *tls_page_iter->ReserveSlot();
    }

    Memory::Page* const tls_page_ptr{kernel.GetUserSlabHeapPages().Allocate()};
    ASSERT(tls_page_ptr);

    const VAddr start{page_table->GetKernelMapRegionStart()};
    const VAddr size{page_table->GetKernelMapRegionEnd() - start};
    const PAddr tls_map_addr{system.DeviceMemory().GetPhysicalAddr(tls_page_ptr)};
    const VAddr tls_page_addr{
        page_table
            ->AllocateAndMapMemory(1, Memory::PageSize, true, start, size / Memory::PageSize,
                                   Memory::MemoryState::ThreadLocal,
                                   Memory::MemoryPermission::ReadAndWrite, tls_map_addr)
            .ValueOr(0)};

    ASSERT(tls_page_addr);

    std::memset(tls_page_ptr, 0, Memory::PageSize);
    tls_pages.emplace_back(tls_page_addr);

    const auto reserve_result{tls_pages.back().ReserveSlot()};
    ASSERT(reserve_result.has_value());

    return *reserve_result;
}

void Process::FreeTLSRegion(VAddr tls_address) {
    KScopedSchedulerLock lock(system.Kernel());
    const VAddr aligned_address = Common::AlignDown(tls_address, Core::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 code_set, VAddr base_addr) {
    std::lock_guard lock{HLE::g_hle_lock};
    const auto ReprotectSegment = [&](const CodeSet::Segment& segment,
                                      Memory::MemoryPermission permission) {
        page_table->SetCodeMemoryPermission(segment.addr + base_addr, segment.size, permission);
    };

    system.Memory().WriteBlock(*this, base_addr, code_set.memory.data(), code_set.memory.size());

    ReprotectSegment(code_set.CodeSegment(), Memory::MemoryPermission::ReadAndExecute);
    ReprotectSegment(code_set.RODataSegment(), Memory::MemoryPermission::Read);
    ReprotectSegment(code_set.DataSegment(), Memory::MemoryPermission::ReadAndWrite);
}

bool Process::IsSignaled() const {
    ASSERT(kernel.GlobalSchedulerContext().IsLocked());
    return is_signaled;
}

Process::Process(Core::System& system)
    : KSynchronizationObject{system.Kernel()},
      page_table{std::make_unique<Memory::PageTable>(system)}, handle_table{system.Kernel()},
      address_arbiter{system}, condition_var{system}, state_lock{system.Kernel()}, system{system} {}

Process::~Process() = default;

void Process::ChangeStatus(ProcessStatus new_status) {
    if (status == new_status) {
        return;
    }

    status = new_status;
    is_signaled = true;
    NotifyAvailable();
}

ResultCode Process::AllocateMainThreadStack(std::size_t stack_size) {
    ASSERT(stack_size);

    // The kernel always ensures that the given stack size is page aligned.
    main_thread_stack_size = Common::AlignUp(stack_size, Memory::PageSize);

    const VAddr start{page_table->GetStackRegionStart()};
    const std::size_t size{page_table->GetStackRegionEnd() - start};

    CASCADE_RESULT(main_thread_stack_top,
                   page_table->AllocateAndMapMemory(
                       main_thread_stack_size / Memory::PageSize, Memory::PageSize, false, start,
                       size / Memory::PageSize, Memory::MemoryState::Stack,
                       Memory::MemoryPermission::ReadAndWrite));

    main_thread_stack_top += main_thread_stack_size;

    return RESULT_SUCCESS;
}

} // namespace Kernel