// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <lib/fzl/resizeable-vmo-mapper.h>
#include <unittest/unittest.h>

#include <fbl/algorithm.h>
#include <utility>

// Note: these tests focus on the added functionality of the resizable VMO
// mapper.  The core functionality is assumed to have already been tested by the
// vmo/vmar tests.
namespace {

constexpr char vmo_name[ZX_MAX_NAME_LEN] = "my-vmo";
constexpr size_t kNonRootVmarSize = (512 << 20);
constexpr zx_vm_option_t kNonRootVmarOpts = ZX_VM_CAN_MAP_SPECIFIC |
                                            ZX_VM_CAN_MAP_READ |
                                            ZX_VM_CAN_MAP_WRITE;

bool ValidateCreateHelper(const fzl::ResizeableVmoMapper& mapper, uint64_t size) {
    BEGIN_HELPER;

    ASSERT_TRUE(mapper.vmo().is_valid());
    ASSERT_EQ(mapper.size(), size);
    ASSERT_NONNULL(mapper.start());

    auto data = static_cast<const uint8_t*>(mapper.start());
    for (size_t i = 0; i < size; ++i) {
        ASSERT_EQ(data[i], 0);
    }

    char name[ZX_MAX_NAME_LEN] = {};
    zx_status_t status = mapper.vmo().get_property(ZX_PROP_NAME, name, fbl::count_of(name));
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < fbl::count_of(name); ++i) {
        ASSERT_EQ(name[i], vmo_name[i]);
    }

    END_HELPER;
}

template <bool NON_ROOT_VMAR>
bool UncheckedCreateHelper(fbl::unique_ptr<fzl::ResizeableVmoMapper>* out_mapper,
                           uint64_t size,
                           const char* name,
                           zx_vm_option_t map_options = ZX_VM_PERM_READ | ZX_VM_PERM_WRITE,
                           uint32_t cache_policy = 0) {
    BEGIN_HELPER;

    fbl::RefPtr<fzl::VmarManager> manager;
    if (NON_ROOT_VMAR) {
        manager = fzl::VmarManager::Create(kNonRootVmarSize, nullptr, kNonRootVmarOpts);
        ASSERT_NONNULL(manager);
    }

    ASSERT_NONNULL(out_mapper);
    *out_mapper = fzl::ResizeableVmoMapper::Create(size,
                                                   name,
                                                   map_options,
                                                   std::move(manager),
                                                   cache_policy);
    END_HELPER;
}

template <bool NON_ROOT_VMAR>
bool CreateHelper(fbl::unique_ptr<fzl::ResizeableVmoMapper>* out_mapper,
                  uint64_t size,
                  const char* name,
                  zx_vm_option_t map_options = ZX_VM_PERM_READ | ZX_VM_PERM_WRITE,
                  uint32_t cache_policy = 0) {
    BEGIN_HELPER;

    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(out_mapper,
                                                     size,
                                                     name,
                                                     map_options,
                                                     cache_policy));
    ASSERT_NONNULL(*out_mapper);
    ASSERT_TRUE(ValidateCreateHelper(**out_mapper, size));

    END_HELPER;
}

template <bool NON_ROOT_VMAR>
bool CreateAndMapHelper(fzl::ResizeableVmoMapper* inout_mapper,
                        uint64_t size,
                        const char* name,
                        zx_vm_option_t map_options = ZX_VM_PERM_READ | ZX_VM_PERM_WRITE,
                        uint32_t cache_policy = 0) {
    BEGIN_HELPER;

    fbl::RefPtr<fzl::VmarManager> manager;
    if (NON_ROOT_VMAR) {
        manager = fzl::VmarManager::Create(kNonRootVmarSize, nullptr, kNonRootVmarOpts);
        ASSERT_NONNULL(manager);
    }

    ASSERT_NONNULL(inout_mapper);
    zx_status_t status;
    status = inout_mapper->CreateAndMap(size,
                                        name,
                                        map_options,
                                        std::move(manager),
                                        cache_policy);
    ASSERT_EQ(status, ZX_OK);
    ASSERT_TRUE(ValidateCreateHelper(*inout_mapper, size));

    END_HELPER;
}

template <bool NON_ROOT_VMAR>
bool MapHelper(fzl::ResizeableVmoMapper* inout_mapper,
               zx::vmo vmo,
               uint64_t size,
               zx_vm_option_t map_options = ZX_VM_PERM_READ | ZX_VM_PERM_WRITE) {
    BEGIN_HELPER;

    fbl::RefPtr<fzl::VmarManager> manager;
    if (NON_ROOT_VMAR) {
        manager = fzl::VmarManager::Create(kNonRootVmarSize, nullptr, kNonRootVmarOpts);
        ASSERT_NONNULL(manager);
    }

    ASSERT_NONNULL(inout_mapper);
    zx_status_t status;
    status = inout_mapper->Map(std::move(vmo), size, map_options, std::move(manager));
    ASSERT_EQ(status, ZX_OK);
    ASSERT_TRUE(ValidateCreateHelper(*inout_mapper, size));

    END_HELPER;
}

template <bool NON_ROOT_VMAR>
bool CreateTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, vmo_name));

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool CreateAndMapTest() {
    BEGIN_TEST;

    fzl::ResizeableVmoMapper mapper;
    ASSERT_TRUE(CreateAndMapHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, vmo_name));

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool MapTest() {
    BEGIN_TEST;

    zx::vmo vmo;
    zx_status_t status;

    status = zx::vmo::create(ZX_PAGE_SIZE, 0, &vmo);
    ASSERT_EQ(status, ZX_OK);

    status = vmo.set_property(ZX_PROP_NAME, vmo_name, strlen(vmo_name));
    ASSERT_EQ(status, ZX_OK);

    fzl::ResizeableVmoMapper mapper;
    ASSERT_TRUE(MapHelper<NON_ROOT_VMAR>(&mapper, std::move(vmo), ZX_PAGE_SIZE));

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool MoveTest() {
    BEGIN_TEST;

    fzl::ResizeableVmoMapper mapper1;
    ASSERT_TRUE(CreateAndMapHelper<NON_ROOT_VMAR>(&mapper1, ZX_PAGE_SIZE, vmo_name));

    // Move by construction
    zx_handle_t orig_handle = mapper1.vmo().get();
    void* orig_start = mapper1.start();
    size_t orig_size = mapper1.size();
    const fzl::VmarManager* orig_manager = mapper1.manager().get();

    ASSERT_NE(orig_handle, ZX_HANDLE_INVALID);
    ASSERT_NONNULL(orig_start);
    ASSERT_EQ(orig_size, ZX_PAGE_SIZE);
    if (NON_ROOT_VMAR) {
        ASSERT_NONNULL(orig_manager);
    } else {
        ASSERT_NULL(orig_manager);
    }

    fzl::ResizeableVmoMapper mapper2(std::move(mapper1));;
    ASSERT_EQ(mapper1.vmo().get(), ZX_HANDLE_INVALID);
    ASSERT_NULL(mapper1.start());
    ASSERT_EQ(mapper1.size(), 0);
    ASSERT_NULL(mapper1.manager());

    ASSERT_EQ(mapper2.vmo().get(), orig_handle);
    ASSERT_EQ(mapper2.start(), orig_start);
    ASSERT_EQ(mapper2.size(), orig_size);
    ASSERT_EQ(mapper2.manager().get(), orig_manager);
    ASSERT_TRUE(ValidateCreateHelper(mapper2, orig_size));

    // Move by assignment
    mapper1 = std::move(mapper2);

    ASSERT_EQ(mapper2.vmo().get(), ZX_HANDLE_INVALID);
    ASSERT_NULL(mapper2.start());
    ASSERT_EQ(mapper2.size(), 0);
    ASSERT_NULL(mapper2.manager());

    ASSERT_EQ(mapper1.vmo().get(), orig_handle);
    ASSERT_EQ(mapper1.start(), orig_start);
    ASSERT_EQ(mapper1.size(), orig_size);
    ASSERT_EQ(mapper1.manager().get(), orig_manager);
    ASSERT_TRUE(ValidateCreateHelper(mapper1, orig_size));

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool ReadTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, vmo_name));

    uint8_t bytes[ZX_PAGE_SIZE];
    memset(bytes, 0xff, ZX_PAGE_SIZE);

    zx_status_t status = mapper->vmo().read(bytes, 0, ZX_PAGE_SIZE);
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < ZX_PAGE_SIZE; ++i) {
        ASSERT_EQ(bytes[i], 0);
    }

    END_TEST;
}

// Test that touching memory, then zx_vmo_reading, works as expected.
template <bool NON_ROOT_VMAR>
bool WriteMappingTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, vmo_name));

    auto data = static_cast<uint8_t*>(mapper->start());
    memset(data, 0xff, ZX_PAGE_SIZE);

    uint8_t bytes[ZX_PAGE_SIZE] = {};
    zx_status_t status = mapper->vmo().read(bytes, 0, ZX_PAGE_SIZE);
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < ZX_PAGE_SIZE; ++i) {
        ASSERT_EQ(bytes[i], 0xff);
    }

    END_TEST;
}

// Test that zx_vmo_writing, then reading memory, works as expected.
template <bool NON_ROOT_VMAR>
bool ReadMappingTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, vmo_name));

    uint8_t bytes[ZX_PAGE_SIZE];
    memset(bytes, 0xff, ZX_PAGE_SIZE);
    zx_status_t status = mapper->vmo().write(bytes, 0, ZX_PAGE_SIZE);
    ASSERT_EQ(status, ZX_OK);

    auto data = static_cast<uint8_t*>(mapper->start());
    for (size_t i = 0; i < ZX_PAGE_SIZE; ++i) {
        ASSERT_EQ(data[i], 0xff);
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool EmptyNameTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, ""));
    ASSERT_NONNULL(mapper);

    char name[ZX_MAX_NAME_LEN] = {};
    zx_status_t status = mapper->vmo().get_property(ZX_PROP_NAME, name, ZX_MAX_NAME_LEN);
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < ZX_MAX_NAME_LEN; ++i) {
        ASSERT_EQ(name[i], 0);
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool NullptrNameTest() {
    BEGIN_TEST;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, nullptr));
    ASSERT_NONNULL(mapper);

    char name[ZX_MAX_NAME_LEN] = {};
    zx_status_t status = mapper->vmo().get_property(ZX_PROP_NAME, name, ZX_MAX_NAME_LEN);
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < ZX_MAX_NAME_LEN; ++i) {
        ASSERT_EQ(name[i], 0);
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool LongNameTest() {
    BEGIN_TEST;

    char long_name[ZX_PAGE_SIZE];
    memset(long_name, 'x', ZX_PAGE_SIZE);
    long_name[ZX_PAGE_SIZE - 1] = 0;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(&mapper, ZX_PAGE_SIZE, long_name));
    ASSERT_NONNULL(mapper);

    char name[ZX_MAX_NAME_LEN] = {};
    zx_status_t status = mapper->vmo().get_property(ZX_PROP_NAME, name, ZX_MAX_NAME_LEN);
    ASSERT_EQ(status, ZX_OK);
    for (size_t i = 0; i < ZX_MAX_NAME_LEN - 1; ++i) {
        ASSERT_EQ(name[i], 'x');
    }
    ASSERT_EQ(name[ZX_MAX_NAME_LEN - 1], 0);

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool GoodSizesTest() {
    BEGIN_TEST;

    static const size_t sizes[] = {
        ZX_PAGE_SIZE,
        16 * ZX_PAGE_SIZE,
        ZX_PAGE_SIZE * ZX_PAGE_SIZE,
        ZX_PAGE_SIZE + 1,
    };

    for (size_t size : sizes) {
        fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
        ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, size, vmo_name));
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool BadSizesTest() {
    BEGIN_TEST;

    // Size 0 should fail.
    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(&mapper, 0, vmo_name));
    ASSERT_NULL(mapper);

    // So should an aburdly big request.
    ASSERT_TRUE(UncheckedCreateHelper<NON_ROOT_VMAR>(&mapper, SIZE_MAX, vmo_name));
    ASSERT_NULL(mapper);

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool GoodShrinkTest() {
    BEGIN_TEST;

    size_t size = ZX_PAGE_SIZE * ZX_PAGE_SIZE;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, size, vmo_name));

    while (size > 2 * ZX_PAGE_SIZE) {
        // The current size.
        zx_status_t status = mapper->Shrink(mapper->size());
        ASSERT_EQ(status, ZX_OK);
        ASSERT_EQ(mapper->size(), size);

        // A paged aligned size.
        size >>= 1;
        status = mapper->Shrink(size);
        ASSERT_EQ(status, ZX_OK);
        ASSERT_EQ(mapper->size(), size);
    }

    // TODO: Test that shrinking the map causes subsequent memory
    // accesses to fail.

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool BadShrinkTest() {
    BEGIN_TEST;

    constexpr size_t size = 16 * ZX_PAGE_SIZE;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, size, vmo_name));

    // Shrinking to 0 should fail.
    zx_status_t status = mapper->Shrink(0);
    ASSERT_EQ(status, ZX_ERR_INVALID_ARGS);
    ASSERT_EQ(mapper->size(), size);

    // Growing via shrink should also fail.
    status = mapper->Shrink(2 * mapper->size());
    ASSERT_EQ(status, ZX_ERR_INVALID_ARGS);
    ASSERT_EQ(mapper->size(), size);

    // Growing to a misaligned size should also fail.
    status = mapper->Shrink(ZX_PAGE_SIZE + 23);
    ASSERT_EQ(status, ZX_ERR_INVALID_ARGS);
    ASSERT_EQ(mapper->size(), size);

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool AlignedGoodGrowTest() {
    BEGIN_TEST;

    constexpr size_t original_size = ZX_PAGE_SIZE;
    constexpr size_t grow_size = 2 * ZX_PAGE_SIZE;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, original_size, vmo_name));

    // Growing to the current size should always succeed.
    zx_status_t status = mapper->Grow(mapper->size());
    ASSERT_EQ(status, ZX_OK);

    status = mapper->Grow(grow_size);
    if (status == ZX_OK) {
        ASSERT_EQ(mapper->size(), grow_size);
        // Check the last byte.
        auto data = static_cast<const uint8_t*>(mapper->start());
        ASSERT_EQ(data[grow_size - 1], 0);
    } else {
        // We might just get unlucky and get a ZX_PAGE_SIZE adjacent to
        // something and not be able to grow. If so, assert that the
        // size did not change.
        ASSERT_EQ(mapper->size(), original_size);
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool UnalignedGoodGrowTest() {
    BEGIN_TEST;

    constexpr size_t original_size = ZX_PAGE_SIZE;
    constexpr size_t grow_size = 2 * ZX_PAGE_SIZE + 1;
    constexpr size_t rounded_grow_size = 3 * ZX_PAGE_SIZE;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, original_size, vmo_name));

    // Growing to the current size should always succeed.
    zx_status_t status = mapper->Grow(mapper->size());
    ASSERT_EQ(status, ZX_OK);

    status = mapper->Grow(grow_size);
    if (status == ZX_OK) {
        ASSERT_EQ(mapper->size(), rounded_grow_size);
        // Check the last byte.
        auto data = static_cast<const uint8_t*>(mapper->start());
        ASSERT_EQ(data[grow_size - 1], 0);
    } else {
        // We might just get unlucky and get a ZX_PAGE_SIZE adjacent to
        // something and not be able to grow. If so, assert that the
        // size did not change.
        ASSERT_EQ(mapper->size(), original_size);
    }

    END_TEST;
}

template <bool NON_ROOT_VMAR>
bool BadGrowTest() {
    BEGIN_TEST;

    constexpr size_t original_size = 2 * ZX_PAGE_SIZE;
    constexpr size_t grow_size = ZX_PAGE_SIZE;

    fbl::unique_ptr<fzl::ResizeableVmoMapper> mapper;
    ASSERT_TRUE(CreateHelper<NON_ROOT_VMAR>(&mapper, original_size, vmo_name));

    // Growing from 2 pages to 1 should fail.
    zx_status_t status = mapper->Grow(grow_size);
    ASSERT_EQ(status, ZX_ERR_INVALID_ARGS);
    ASSERT_EQ(mapper->size(), original_size);

    // Growing from 2 pages to nothing should also fail.
    status = mapper->Grow(0);
    ASSERT_EQ(status, ZX_ERR_INVALID_ARGS);
    ASSERT_EQ(mapper->size(), original_size);

    END_TEST;
}

}  // namespace

#define MAKE_TEST(_name) \
    RUN_NAMED_TEST(#_name "_RootVmar",    _name<false>) \
    RUN_NAMED_TEST(#_name "_NON_ROOT_VMAR", _name<true>)

BEGIN_TEST_CASE(resizeable_vmo_mapper_tests)
MAKE_TEST(CreateTest)
MAKE_TEST(CreateAndMapTest)
MAKE_TEST(MapTest)
MAKE_TEST(MoveTest)
MAKE_TEST(ReadTest)
MAKE_TEST(WriteMappingTest)
MAKE_TEST(ReadMappingTest)
MAKE_TEST(EmptyNameTest)
MAKE_TEST(NullptrNameTest)
MAKE_TEST(LongNameTest)
MAKE_TEST(GoodSizesTest)
MAKE_TEST(BadSizesTest)
MAKE_TEST(GoodShrinkTest)
MAKE_TEST(BadShrinkTest)
MAKE_TEST(AlignedGoodGrowTest)
MAKE_TEST(UnalignedGoodGrowTest)
MAKE_TEST(BadGrowTest)
END_TEST_CASE(resizeable_vmo_mapper_tests)

#undef MAKE_TEST