/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "mem_map.h"
#include <memory>
#include "gtest/gtest.h"
namespace art {
class MemMapTest : public testing::Test {
public:
static byte* BaseBegin(MemMap* mem_map) {
return reinterpret_cast<byte*>(mem_map->base_begin_);
}
static size_t BaseSize(MemMap* mem_map) {
return mem_map->base_size_;
}
static void RemapAtEndTest(bool low_4gb) {
std::string error_msg;
// Cast the page size to size_t.
const size_t page_size = static_cast<size_t>(kPageSize);
// Map a two-page memory region.
MemMap* m0 = MemMap::MapAnonymous("MemMapTest_RemapAtEndTest_map0",
nullptr,
2 * page_size,
PROT_READ | PROT_WRITE,
low_4gb,
&error_msg);
// Check its state and write to it.
byte* base0 = m0->Begin();
ASSERT_TRUE(base0 != nullptr) << error_msg;
size_t size0 = m0->Size();
EXPECT_EQ(m0->Size(), 2 * page_size);
EXPECT_EQ(BaseBegin(m0), base0);
EXPECT_EQ(BaseSize(m0), size0);
memset(base0, 42, 2 * page_size);
// Remap the latter half into a second MemMap.
MemMap* m1 = m0->RemapAtEnd(base0 + page_size,
"MemMapTest_RemapAtEndTest_map1",
PROT_READ | PROT_WRITE,
&error_msg);
// Check the states of the two maps.
EXPECT_EQ(m0->Begin(), base0) << error_msg;
EXPECT_EQ(m0->Size(), page_size);
EXPECT_EQ(BaseBegin(m0), base0);
EXPECT_EQ(BaseSize(m0), page_size);
byte* base1 = m1->Begin();
size_t size1 = m1->Size();
EXPECT_EQ(base1, base0 + page_size);
EXPECT_EQ(size1, page_size);
EXPECT_EQ(BaseBegin(m1), base1);
EXPECT_EQ(BaseSize(m1), size1);
// Write to the second region.
memset(base1, 43, page_size);
// Check the contents of the two regions.
for (size_t i = 0; i < page_size; ++i) {
EXPECT_EQ(base0[i], 42);
}
for (size_t i = 0; i < page_size; ++i) {
EXPECT_EQ(base1[i], 43);
}
// Unmap the first region.
delete m0;
// Make sure the second region is still accessible after the first
// region is unmapped.
for (size_t i = 0; i < page_size; ++i) {
EXPECT_EQ(base1[i], 43);
}
delete m1;
}
void CommonInit() {
MemMap::Init();
}
#if defined(__LP64__) && !defined(__x86_64__)
static uintptr_t GetLinearScanPos() {
return MemMap::next_mem_pos_;
}
#endif
};
#if defined(__LP64__) && !defined(__x86_64__)
#ifdef __BIONIC__
extern uintptr_t CreateStartPos(uint64_t input);
#endif
TEST_F(MemMapTest, Start) {
CommonInit();
uintptr_t start = GetLinearScanPos();
EXPECT_LE(64 * KB, start);
EXPECT_LT(start, static_cast<uintptr_t>(ART_BASE_ADDRESS));
#ifdef __BIONIC__
// Test a couple of values. Make sure they are different.
uintptr_t last = 0;
for (size_t i = 0; i < 100; ++i) {
uintptr_t random_start = CreateStartPos(i * kPageSize);
EXPECT_NE(last, random_start);
last = random_start;
}
// Even on max, should be below ART_BASE_ADDRESS.
EXPECT_LT(CreateStartPos(~0), static_cast<uintptr_t>(ART_BASE_ADDRESS));
#endif
// End of test.
}
#endif
TEST_F(MemMapTest, MapAnonymousEmpty) {
CommonInit();
std::string error_msg;
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousEmpty",
nullptr,
0,
PROT_READ,
false,
&error_msg));
ASSERT_TRUE(map.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
map.reset(MemMap::MapAnonymous("MapAnonymousEmpty",
nullptr,
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
}
#ifdef __LP64__
TEST_F(MemMapTest, MapAnonymousEmpty32bit) {
CommonInit();
std::string error_msg;
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousEmpty",
nullptr,
kPageSize,
PROT_READ | PROT_WRITE,
true,
&error_msg));
ASSERT_TRUE(map.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
ASSERT_LT(reinterpret_cast<uintptr_t>(BaseBegin(map.get())), 1ULL << 32);
}
#endif
TEST_F(MemMapTest, MapAnonymousExactAddr) {
CommonInit();
std::string error_msg;
// Map at an address that should work, which should succeed.
std::unique_ptr<MemMap> map0(MemMap::MapAnonymous("MapAnonymous0",
reinterpret_cast<byte*>(ART_BASE_ADDRESS),
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map0.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
ASSERT_TRUE(map0->BaseBegin() == reinterpret_cast<void*>(ART_BASE_ADDRESS));
// Map at an unspecified address, which should succeed.
std::unique_ptr<MemMap> map1(MemMap::MapAnonymous("MapAnonymous1",
nullptr,
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map1.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
ASSERT_TRUE(map1->BaseBegin() != nullptr);
// Attempt to map at the same address, which should fail.
std::unique_ptr<MemMap> map2(MemMap::MapAnonymous("MapAnonymous2",
reinterpret_cast<byte*>(map1->BaseBegin()),
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map2.get() == nullptr) << error_msg;
ASSERT_TRUE(!error_msg.empty());
}
TEST_F(MemMapTest, RemapAtEnd) {
RemapAtEndTest(false);
}
#ifdef __LP64__
TEST_F(MemMapTest, RemapAtEnd32bit) {
RemapAtEndTest(true);
}
#endif
TEST_F(MemMapTest, MapAnonymousExactAddr32bitHighAddr) {
uintptr_t start_addr = ART_BASE_ADDRESS + 0x1000000;
std::string error_msg;
CommonInit();
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousExactAddr32bitHighAddr",
reinterpret_cast<byte*>(start_addr),
0x21000000,
PROT_READ | PROT_WRITE,
true,
&error_msg));
ASSERT_TRUE(map.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
ASSERT_EQ(reinterpret_cast<uintptr_t>(BaseBegin(map.get())), start_addr);
}
TEST_F(MemMapTest, MapAnonymousOverflow) {
CommonInit();
std::string error_msg;
uintptr_t ptr = 0;
ptr -= kPageSize; // Now it's close to the top.
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousOverflow",
reinterpret_cast<byte*>(ptr),
2 * kPageSize, // brings it over the top.
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_EQ(nullptr, map.get());
ASSERT_FALSE(error_msg.empty());
}
#ifdef __LP64__
TEST_F(MemMapTest, MapAnonymousLow4GBExpectedTooHigh) {
CommonInit();
std::string error_msg;
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousLow4GBExpectedTooHigh",
reinterpret_cast<byte*>(UINT64_C(0x100000000)),
kPageSize,
PROT_READ | PROT_WRITE,
true,
&error_msg));
ASSERT_EQ(nullptr, map.get());
ASSERT_FALSE(error_msg.empty());
}
TEST_F(MemMapTest, MapAnonymousLow4GBRangeTooHigh) {
CommonInit();
std::string error_msg;
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymousLow4GBRangeTooHigh",
reinterpret_cast<byte*>(0xF0000000),
0x20000000,
PROT_READ | PROT_WRITE,
true,
&error_msg));
ASSERT_EQ(nullptr, map.get());
ASSERT_FALSE(error_msg.empty());
}
#endif
TEST_F(MemMapTest, CheckNoGaps) {
CommonInit();
std::string error_msg;
constexpr size_t kNumPages = 3;
// Map a 3-page mem map.
std::unique_ptr<MemMap> map(MemMap::MapAnonymous("MapAnonymous0",
nullptr,
kPageSize * kNumPages,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
// Record the base address.
byte* map_base = reinterpret_cast<byte*>(map->BaseBegin());
// Unmap it.
map.reset();
// Map at the same address, but in page-sized separate mem maps,
// assuming the space at the address is still available.
std::unique_ptr<MemMap> map0(MemMap::MapAnonymous("MapAnonymous0",
map_base,
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map0.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
std::unique_ptr<MemMap> map1(MemMap::MapAnonymous("MapAnonymous1",
map_base + kPageSize,
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map1.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
std::unique_ptr<MemMap> map2(MemMap::MapAnonymous("MapAnonymous2",
map_base + kPageSize * 2,
kPageSize,
PROT_READ | PROT_WRITE,
false,
&error_msg));
ASSERT_TRUE(map2.get() != nullptr) << error_msg;
ASSERT_TRUE(error_msg.empty());
// One-map cases.
ASSERT_TRUE(MemMap::CheckNoGaps(map0.get(), map0.get()));
ASSERT_TRUE(MemMap::CheckNoGaps(map1.get(), map1.get()));
ASSERT_TRUE(MemMap::CheckNoGaps(map2.get(), map2.get()));
// Two or three-map cases.
ASSERT_TRUE(MemMap::CheckNoGaps(map0.get(), map1.get()));
ASSERT_TRUE(MemMap::CheckNoGaps(map1.get(), map2.get()));
ASSERT_TRUE(MemMap::CheckNoGaps(map0.get(), map2.get()));
// Unmap the middle one.
map1.reset();
// Should return false now that there's a gap in the middle.
ASSERT_FALSE(MemMap::CheckNoGaps(map0.get(), map2.get()));
}
} // namespace art