diff options
Diffstat (limited to 'src/common/host_memory.cpp')
| -rw-r--r-- | src/common/host_memory.cpp | 538 |
1 files changed, 538 insertions, 0 deletions
diff --git a/src/common/host_memory.cpp b/src/common/host_memory.cpp new file mode 100644 index 000000000..8bd70abc7 --- /dev/null +++ b/src/common/host_memory.cpp @@ -0,0 +1,538 @@ +#ifdef _WIN32 + +#include <iterator> +#include <unordered_map> +#include <boost/icl/separate_interval_set.hpp> +#include <windows.h> +#include "common/dynamic_library.h" + +#elif defined(__linux__) // ^^^ Windows ^^^ vvv Linux vvv + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif +#include <fcntl.h> +#include <sys/mman.h> +#include <unistd.h> + +#endif // ^^^ Linux ^^^ + +#include <mutex> + +#include "common/alignment.h" +#include "common/assert.h" +#include "common/host_memory.h" +#include "common/logging/log.h" +#include "common/scope_exit.h" + +namespace Common { + +constexpr size_t PageAlignment = 0x1000; +constexpr size_t HugePageSize = 0x200000; + +#ifdef _WIN32 + +// Manually imported for MinGW compatibility +#ifndef MEM_RESERVE_PLACEHOLDER +#define MEM_RESERVE_PLACEHOLDER 0x0004000 +#endif +#ifndef MEM_REPLACE_PLACEHOLDER +#define MEM_REPLACE_PLACEHOLDER 0x00004000 +#endif +#ifndef MEM_COALESCE_PLACEHOLDERS +#define MEM_COALESCE_PLACEHOLDERS 0x00000001 +#endif +#ifndef MEM_PRESERVE_PLACEHOLDER +#define MEM_PRESERVE_PLACEHOLDER 0x00000002 +#endif + +using PFN_CreateFileMapping2 = _Ret_maybenull_ HANDLE(WINAPI*)( + _In_ HANDLE File, _In_opt_ SECURITY_ATTRIBUTES* SecurityAttributes, _In_ ULONG DesiredAccess, + _In_ ULONG PageProtection, _In_ ULONG AllocationAttributes, _In_ ULONG64 MaximumSize, + _In_opt_ PCWSTR Name, + _Inout_updates_opt_(ParameterCount) MEM_EXTENDED_PARAMETER* ExtendedParameters, + _In_ ULONG ParameterCount); + +using PFN_VirtualAlloc2 = _Ret_maybenull_ PVOID(WINAPI*)( + _In_opt_ HANDLE Process, _In_opt_ PVOID BaseAddress, _In_ SIZE_T Size, + _In_ ULONG AllocationType, _In_ ULONG PageProtection, + _Inout_updates_opt_(ParameterCount) MEM_EXTENDED_PARAMETER* ExtendedParameters, + _In_ ULONG ParameterCount); + +using PFN_MapViewOfFile3 = _Ret_maybenull_ PVOID(WINAPI*)( + _In_ HANDLE FileMapping, _In_opt_ HANDLE Process, _In_opt_ PVOID BaseAddress, + _In_ ULONG64 Offset, _In_ SIZE_T ViewSize, _In_ ULONG AllocationType, _In_ ULONG PageProtection, + _Inout_updates_opt_(ParameterCount) MEM_EXTENDED_PARAMETER* ExtendedParameters, + _In_ ULONG ParameterCount); + +using PFN_UnmapViewOfFile2 = BOOL(WINAPI*)(_In_ HANDLE Process, _In_ PVOID BaseAddress, + _In_ ULONG UnmapFlags); + +template <typename T> +static void GetFuncAddress(Common::DynamicLibrary& dll, const char* name, T& pfn) { + if (!dll.GetSymbol(name, &pfn)) { + LOG_CRITICAL(HW_Memory, "Failed to load {}", name); + throw std::bad_alloc{}; + } +} + +class HostMemory::Impl { +public: + explicit Impl(size_t backing_size_, size_t virtual_size_) + : backing_size{backing_size_}, virtual_size{virtual_size_}, process{GetCurrentProcess()}, + kernelbase_dll("Kernelbase") { + if (!kernelbase_dll.IsOpen()) { + LOG_CRITICAL(HW_Memory, "Failed to load Kernelbase.dll"); + throw std::bad_alloc{}; + } + GetFuncAddress(kernelbase_dll, "CreateFileMapping2", pfn_CreateFileMapping2); + GetFuncAddress(kernelbase_dll, "VirtualAlloc2", pfn_VirtualAlloc2); + GetFuncAddress(kernelbase_dll, "MapViewOfFile3", pfn_MapViewOfFile3); + GetFuncAddress(kernelbase_dll, "UnmapViewOfFile2", pfn_UnmapViewOfFile2); + + // Allocate backing file map + backing_handle = + pfn_CreateFileMapping2(INVALID_HANDLE_VALUE, nullptr, FILE_MAP_WRITE | FILE_MAP_READ, + PAGE_READWRITE, SEC_COMMIT, backing_size, nullptr, nullptr, 0); + if (!backing_handle) { + LOG_CRITICAL(HW_Memory, "Failed to allocate {} MiB of backing memory", + backing_size >> 20); + throw std::bad_alloc{}; + } + // Allocate a virtual memory for the backing file map as placeholder + backing_base = static_cast<u8*>(pfn_VirtualAlloc2(process, nullptr, backing_size, + MEM_RESERVE | MEM_RESERVE_PLACEHOLDER, + PAGE_NOACCESS, nullptr, 0)); + if (!backing_base) { + Release(); + LOG_CRITICAL(HW_Memory, "Failed to reserve {} MiB of virtual memory", + backing_size >> 20); + throw std::bad_alloc{}; + } + // Map backing placeholder + void* const ret = pfn_MapViewOfFile3(backing_handle, process, backing_base, 0, backing_size, + MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, nullptr, 0); + if (ret != backing_base) { + Release(); + LOG_CRITICAL(HW_Memory, "Failed to map {} MiB of virtual memory", backing_size >> 20); + throw std::bad_alloc{}; + } + // Allocate virtual address placeholder + virtual_base = static_cast<u8*>(pfn_VirtualAlloc2(process, nullptr, virtual_size, + MEM_RESERVE | MEM_RESERVE_PLACEHOLDER, + PAGE_NOACCESS, nullptr, 0)); + if (!virtual_base) { + Release(); + LOG_CRITICAL(HW_Memory, "Failed to reserve {} GiB of virtual memory", + virtual_size >> 30); + throw std::bad_alloc{}; + } + } + + ~Impl() { + Release(); + } + + void Map(size_t virtual_offset, size_t host_offset, size_t length) { + std::unique_lock lock{placeholder_mutex}; + if (!IsNiechePlaceholder(virtual_offset, length)) { + Split(virtual_offset, length); + } + ASSERT(placeholders.find({virtual_offset, virtual_offset + length}) == placeholders.end()); + TrackPlaceholder(virtual_offset, host_offset, length); + + MapView(virtual_offset, host_offset, length); + } + + void Unmap(size_t virtual_offset, size_t length) { + std::lock_guard lock{placeholder_mutex}; + + // Unmap until there are no more placeholders + while (UnmapOnePlaceholder(virtual_offset, length)) { + } + } + + void Protect(size_t virtual_offset, size_t length, bool read, bool write) { + DWORD new_flags{}; + if (read && write) { + new_flags = PAGE_READWRITE; + } else if (read && !write) { + new_flags = PAGE_READONLY; + } else if (!read && !write) { + new_flags = PAGE_NOACCESS; + } else { + UNIMPLEMENTED_MSG("Protection flag combination read={} write={}", read, write); + } + const size_t virtual_end = virtual_offset + length; + + std::lock_guard lock{placeholder_mutex}; + auto [it, end] = placeholders.equal_range({virtual_offset, virtual_end}); + while (it != end) { + const size_t offset = std::max(it->lower(), virtual_offset); + const size_t protect_length = std::min(it->upper(), virtual_end) - offset; + DWORD old_flags{}; + if (!VirtualProtect(virtual_base + offset, protect_length, new_flags, &old_flags)) { + LOG_CRITICAL(HW_Memory, "Failed to change virtual memory protect rules"); + } + ++it; + } + } + + const size_t backing_size; ///< Size of the backing memory in bytes + const size_t virtual_size; ///< Size of the virtual address placeholder in bytes + + u8* backing_base{}; + u8* virtual_base{}; + +private: + /// Release all resources in the object + void Release() { + if (!placeholders.empty()) { + for (const auto& placeholder : placeholders) { + if (!pfn_UnmapViewOfFile2(process, virtual_base + placeholder.lower(), + MEM_PRESERVE_PLACEHOLDER)) { + LOG_CRITICAL(HW_Memory, "Failed to unmap virtual memory placeholder"); + } + } + Coalesce(0, virtual_size); + } + if (virtual_base) { + if (!VirtualFree(virtual_base, 0, MEM_RELEASE)) { + LOG_CRITICAL(HW_Memory, "Failed to free virtual memory"); + } + } + if (backing_base) { + if (!pfn_UnmapViewOfFile2(process, backing_base, MEM_PRESERVE_PLACEHOLDER)) { + LOG_CRITICAL(HW_Memory, "Failed to unmap backing memory placeholder"); + } + if (!VirtualFreeEx(process, backing_base, 0, MEM_RELEASE)) { + LOG_CRITICAL(HW_Memory, "Failed to free backing memory"); + } + } + if (!CloseHandle(backing_handle)) { + LOG_CRITICAL(HW_Memory, "Failed to free backing memory file handle"); + } + } + + /// Unmap one placeholder in the given range (partial unmaps are supported) + /// Return true when there are no more placeholders to unmap + bool UnmapOnePlaceholder(size_t virtual_offset, size_t length) { + const auto it = placeholders.find({virtual_offset, virtual_offset + length}); + const auto begin = placeholders.begin(); + const auto end = placeholders.end(); + if (it == end) { + return false; + } + const size_t placeholder_begin = it->lower(); + const size_t placeholder_end = it->upper(); + const size_t unmap_begin = std::max(virtual_offset, placeholder_begin); + const size_t unmap_end = std::min(virtual_offset + length, placeholder_end); + ASSERT(unmap_begin >= placeholder_begin && unmap_begin < placeholder_end); + ASSERT(unmap_end <= placeholder_end && unmap_end > placeholder_begin); + + const auto host_pointer_it = placeholder_host_pointers.find(placeholder_begin); + ASSERT(host_pointer_it != placeholder_host_pointers.end()); + const size_t host_offset = host_pointer_it->second; + + const bool split_left = unmap_begin > placeholder_begin; + const bool split_right = unmap_end < placeholder_end; + + if (!pfn_UnmapViewOfFile2(process, virtual_base + placeholder_begin, + MEM_PRESERVE_PLACEHOLDER)) { + LOG_CRITICAL(HW_Memory, "Failed to unmap placeholder"); + } + // If we have to remap memory regions due to partial unmaps, we are in a data race as + // Windows doesn't support remapping memory without unmapping first. Avoid adding any extra + // logic within the panic region described below. + + // Panic region, we are in a data race right now + if (split_left || split_right) { + Split(unmap_begin, unmap_end - unmap_begin); + } + if (split_left) { + MapView(placeholder_begin, host_offset, unmap_begin - placeholder_begin); + } + if (split_right) { + MapView(unmap_end, host_offset + unmap_end - placeholder_begin, + placeholder_end - unmap_end); + } + // End panic region + + size_t coalesce_begin = unmap_begin; + if (!split_left) { + // Try to coalesce pages to the left + coalesce_begin = it == begin ? 0 : std::prev(it)->upper(); + if (coalesce_begin != placeholder_begin) { + Coalesce(coalesce_begin, unmap_end - coalesce_begin); + } + } + if (!split_right) { + // Try to coalesce pages to the right + const auto next = std::next(it); + const size_t next_begin = next == end ? virtual_size : next->lower(); + if (placeholder_end != next_begin) { + // We can coalesce to the right + Coalesce(coalesce_begin, next_begin - coalesce_begin); + } + } + // Remove and reinsert placeholder trackers + UntrackPlaceholder(it); + if (split_left) { + TrackPlaceholder(placeholder_begin, host_offset, unmap_begin - placeholder_begin); + } + if (split_right) { + TrackPlaceholder(unmap_end, host_offset + unmap_end - placeholder_begin, + placeholder_end - unmap_end); + } + return true; + } + + void MapView(size_t virtual_offset, size_t host_offset, size_t length) { + if (!pfn_MapViewOfFile3(backing_handle, process, virtual_base + virtual_offset, host_offset, + length, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, nullptr, 0)) { + LOG_CRITICAL(HW_Memory, "Failed to map placeholder"); + } + } + + void Split(size_t virtual_offset, size_t length) { + if (!VirtualFreeEx(process, reinterpret_cast<LPVOID>(virtual_base + virtual_offset), length, + MEM_RELEASE | MEM_PRESERVE_PLACEHOLDER)) { + LOG_CRITICAL(HW_Memory, "Failed to split placeholder"); + } + } + + void Coalesce(size_t virtual_offset, size_t length) { + if (!VirtualFreeEx(process, reinterpret_cast<LPVOID>(virtual_base + virtual_offset), length, + MEM_RELEASE | MEM_COALESCE_PLACEHOLDERS)) { + LOG_CRITICAL(HW_Memory, "Failed to coalesce placeholders"); + } + } + + void TrackPlaceholder(size_t virtual_offset, size_t host_offset, size_t length) { + placeholders.insert({virtual_offset, virtual_offset + length}); + placeholder_host_pointers.emplace(virtual_offset, host_offset); + } + + void UntrackPlaceholder(boost::icl::separate_interval_set<size_t>::iterator it) { + placeholders.erase(it); + placeholder_host_pointers.erase(it->lower()); + } + + /// Return true when a given memory region is a "nieche" and the placeholders don't have to be + /// splitted. + bool IsNiechePlaceholder(size_t virtual_offset, size_t length) const { + const auto it = placeholders.upper_bound({virtual_offset, virtual_offset + length}); + if (it != placeholders.end() && it->lower() == virtual_offset + length) { + const bool is_root = it == placeholders.begin() && virtual_offset == 0; + return is_root || std::prev(it)->upper() == virtual_offset; + } + return false; + } + + HANDLE process{}; ///< Current process handle + HANDLE backing_handle{}; ///< File based backing memory + + DynamicLibrary kernelbase_dll; + PFN_CreateFileMapping2 pfn_CreateFileMapping2{}; + PFN_VirtualAlloc2 pfn_VirtualAlloc2{}; + PFN_MapViewOfFile3 pfn_MapViewOfFile3{}; + PFN_UnmapViewOfFile2 pfn_UnmapViewOfFile2{}; + + std::mutex placeholder_mutex; ///< Mutex for placeholders + boost::icl::separate_interval_set<size_t> placeholders; ///< Mapped placeholders + std::unordered_map<size_t, size_t> placeholder_host_pointers; ///< Placeholder backing offset +}; + +#elif defined(__linux__) // ^^^ Windows ^^^ vvv Linux vvv + +class HostMemory::Impl { +public: + explicit Impl(size_t backing_size_, size_t virtual_size_) + : backing_size{backing_size_}, virtual_size{virtual_size_} { + bool good = false; + SCOPE_EXIT({ + if (!good) { + Release(); + } + }); + + // Backing memory initialization + fd = memfd_create("HostMemory", 0); + if (fd == -1) { + LOG_CRITICAL(HW_Memory, "memfd_create failed: {}", strerror(errno)); + throw std::bad_alloc{}; + } + + // Defined to extend the file with zeros + int ret = ftruncate(fd, backing_size); + if (ret != 0) { + LOG_CRITICAL(HW_Memory, "ftruncate failed with {}, are you out-of-memory?", + strerror(errno)); + throw std::bad_alloc{}; + } + + backing_base = static_cast<u8*>( + mmap(nullptr, backing_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)); + if (backing_base == MAP_FAILED) { + LOG_CRITICAL(HW_Memory, "mmap failed: {}", strerror(errno)); + throw std::bad_alloc{}; + } + + // Virtual memory initialization + virtual_base = static_cast<u8*>( + mmap(nullptr, virtual_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0)); + if (virtual_base == MAP_FAILED) { + LOG_CRITICAL(HW_Memory, "mmap failed: {}", strerror(errno)); + throw std::bad_alloc{}; + } + + good = true; + } + + ~Impl() { + Release(); + } + + void Map(size_t virtual_offset, size_t host_offset, size_t length) { + + void* ret = mmap(virtual_base + virtual_offset, length, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_FIXED, fd, host_offset); + ASSERT_MSG(ret != MAP_FAILED, "mmap failed: {}", strerror(errno)); + } + + void Unmap(size_t virtual_offset, size_t length) { + // The method name is wrong. We're still talking about the virtual range. + // We don't want to unmap, we want to reserve this memory. + + void* ret = mmap(virtual_base + virtual_offset, length, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); + ASSERT_MSG(ret != MAP_FAILED, "mmap failed: {}", strerror(errno)); + } + + void Protect(size_t virtual_offset, size_t length, bool read, bool write) { + int flags = 0; + if (read) { + flags |= PROT_READ; + } + if (write) { + flags |= PROT_WRITE; + } + int ret = mprotect(virtual_base + virtual_offset, length, flags); + ASSERT_MSG(ret == 0, "mprotect failed: {}", strerror(errno)); + } + + const size_t backing_size; ///< Size of the backing memory in bytes + const size_t virtual_size; ///< Size of the virtual address placeholder in bytes + + u8* backing_base{reinterpret_cast<u8*>(MAP_FAILED)}; + u8* virtual_base{reinterpret_cast<u8*>(MAP_FAILED)}; + +private: + /// Release all resources in the object + void Release() { + if (virtual_base != MAP_FAILED) { + int ret = munmap(virtual_base, virtual_size); + ASSERT_MSG(ret == 0, "munmap failed: {}", strerror(errno)); + } + + if (backing_base != MAP_FAILED) { + int ret = munmap(backing_base, backing_size); + ASSERT_MSG(ret == 0, "munmap failed: {}", strerror(errno)); + } + + if (fd != -1) { + int ret = close(fd); + ASSERT_MSG(ret == 0, "close failed: {}", strerror(errno)); + } + } + + int fd{-1}; // memfd file descriptor, -1 is the error value of memfd_create +}; + +#else // ^^^ Linux ^^^ vvv Generic vvv + +class HostMemory::Impl { +public: + explicit Impl(size_t /*backing_size */, size_t /* virtual_size */) { + // This is just a place holder. + // Please implement fastmem in a propper way on your platform. + throw std::bad_alloc{}; + } + + void Map(size_t virtual_offset, size_t host_offset, size_t length) {} + + void Unmap(size_t virtual_offset, size_t length) {} + + void Protect(size_t virtual_offset, size_t length, bool read, bool write) {} + + u8* backing_base{nullptr}; + u8* virtual_base{nullptr}; +}; + +#endif // ^^^ Generic ^^^ + +HostMemory::HostMemory(size_t backing_size_, size_t virtual_size_) + : backing_size(backing_size_), virtual_size(virtual_size_) { + try { + // Try to allocate a fastmem arena. + // The implementation will fail with std::bad_alloc on errors. + impl = std::make_unique<HostMemory::Impl>(AlignUp(backing_size, PageAlignment), + AlignUp(virtual_size, PageAlignment) + + 3 * HugePageSize); + backing_base = impl->backing_base; + virtual_base = impl->virtual_base; + + if (virtual_base) { + virtual_base += 2 * HugePageSize - 1; + virtual_base -= reinterpret_cast<size_t>(virtual_base) & (HugePageSize - 1); + virtual_base_offset = virtual_base - impl->virtual_base; + } + + } catch (const std::bad_alloc&) { + LOG_CRITICAL(HW_Memory, + "Fastmem unavailable, falling back to VirtualBuffer for memory allocation"); + fallback_buffer = std::make_unique<Common::VirtualBuffer<u8>>(backing_size); + backing_base = fallback_buffer->data(); + virtual_base = nullptr; + } +} + +HostMemory::~HostMemory() = default; + +HostMemory::HostMemory(HostMemory&&) noexcept = default; + +HostMemory& HostMemory::operator=(HostMemory&&) noexcept = default; + +void HostMemory::Map(size_t virtual_offset, size_t host_offset, size_t length) { + ASSERT(virtual_offset % PageAlignment == 0); + ASSERT(host_offset % PageAlignment == 0); + ASSERT(length % PageAlignment == 0); + ASSERT(virtual_offset + length <= virtual_size); + ASSERT(host_offset + length <= backing_size); + if (length == 0 || !virtual_base || !impl) { + return; + } + impl->Map(virtual_offset + virtual_base_offset, host_offset, length); +} + +void HostMemory::Unmap(size_t virtual_offset, size_t length) { + ASSERT(virtual_offset % PageAlignment == 0); + ASSERT(length % PageAlignment == 0); + ASSERT(virtual_offset + length <= virtual_size); + if (length == 0 || !virtual_base || !impl) { + return; + } + impl->Unmap(virtual_offset + virtual_base_offset, length); +} + +void HostMemory::Protect(size_t virtual_offset, size_t length, bool read, bool write) { + ASSERT(virtual_offset % PageAlignment == 0); + ASSERT(length % PageAlignment == 0); + ASSERT(virtual_offset + length <= virtual_size); + if (length == 0 || !virtual_base || !impl) { + return; + } + impl->Protect(virtual_offset + virtual_base_offset, length, read, write); +} + +} // namespace Common |