| // Copyright 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef BASE_ALLOCATOR_ALLOCATOR_SHIM_H_ |
| #define BASE_ALLOCATOR_ALLOCATOR_SHIM_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include "base/allocator/buildflags.h" |
| #include "base/allocator/partition_allocator/partition_alloc_config.h" |
| #include "base/base_export.h" |
| #include "base/types/strong_alias.h" |
| #include "build/build_config.h" |
| |
| #if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) && defined(PA_ALLOW_PCSCAN) |
| #include "base/allocator/partition_allocator/starscan/pcscan.h" |
| #endif |
| |
| namespace base { |
| namespace allocator { |
| |
| // Allocator Shim API. Allows to: |
| // - Configure the behavior of the allocator (what to do on OOM failures). |
| // - Install new hooks (AllocatorDispatch) in the allocator chain. |
| |
| // When this shim layer is enabled, the route of an allocation is as-follows: |
| // |
| // [allocator_shim_override_*.h] Intercept malloc() / operator new calls: |
| // The override_* headers define the symbols required to intercept calls to |
| // malloc() and operator new (if not overridden by specific C++ classes). |
| // |
| // [allocator_shim.cc] Routing allocation calls to the shim: |
| // The headers above route the calls to the internal ShimMalloc(), ShimFree(), |
| // ShimCppNew() etc. methods defined in allocator_shim.cc. |
| // These methods will: (1) forward the allocation call to the front of the |
| // AllocatorDispatch chain. (2) perform security hardenings (e.g., might |
| // call std::new_handler on OOM failure). |
| // |
| // [allocator_shim_default_dispatch_to_*.cc] The AllocatorDispatch chain: |
| // It is a singly linked list where each element is a struct with function |
| // pointers (|malloc_function|, |free_function|, etc). Normally the chain |
| // consists of a single AllocatorDispatch element, herein called |
| // the "default dispatch", which is statically defined at build time and |
| // ultimately routes the calls to the actual allocator defined by the build |
| // config (glibc, ...). |
| // |
| // It is possible to dynamically insert further AllocatorDispatch stages |
| // to the front of the chain, for debugging / profiling purposes. |
| // |
| // All the functions must be thread safe. The shim does not enforce any |
| // serialization. This is to route to thread-aware allocators without |
| // introducing unnecessary perf hits. |
| |
| struct AllocatorDispatch { |
| using AllocFn = void*(const AllocatorDispatch* self, |
| size_t size, |
| void* context); |
| using AllocUncheckedFn = void*(const AllocatorDispatch* self, |
| size_t size, |
| void* context); |
| using AllocZeroInitializedFn = void*(const AllocatorDispatch* self, |
| size_t n, |
| size_t size, |
| void* context); |
| using AllocAlignedFn = void*(const AllocatorDispatch* self, |
| size_t alignment, |
| size_t size, |
| void* context); |
| using ReallocFn = void*(const AllocatorDispatch* self, |
| void* address, |
| size_t size, |
| void* context); |
| using FreeFn = void(const AllocatorDispatch* self, |
| void* address, |
| void* context); |
| // Returns the allocated size of user data (not including heap overhead). |
| // Can be larger than the requested size. |
| using GetSizeEstimateFn = size_t(const AllocatorDispatch* self, |
| void* address, |
| void* context); |
| using BatchMallocFn = unsigned(const AllocatorDispatch* self, |
| size_t size, |
| void** results, |
| unsigned num_requested, |
| void* context); |
| using BatchFreeFn = void(const AllocatorDispatch* self, |
| void** to_be_freed, |
| unsigned num_to_be_freed, |
| void* context); |
| using FreeDefiniteSizeFn = void(const AllocatorDispatch* self, |
| void* ptr, |
| size_t size, |
| void* context); |
| using AlignedMallocFn = void*(const AllocatorDispatch* self, |
| size_t size, |
| size_t alignment, |
| void* context); |
| using AlignedReallocFn = void*(const AllocatorDispatch* self, |
| void* address, |
| size_t size, |
| size_t alignment, |
| void* context); |
| using AlignedFreeFn = void(const AllocatorDispatch* self, |
| void* address, |
| void* context); |
| |
| AllocFn* const alloc_function; |
| AllocUncheckedFn* const alloc_unchecked_function; |
| AllocZeroInitializedFn* const alloc_zero_initialized_function; |
| AllocAlignedFn* const alloc_aligned_function; |
| ReallocFn* const realloc_function; |
| FreeFn* const free_function; |
| GetSizeEstimateFn* const get_size_estimate_function; |
| // batch_malloc, batch_free, and free_definite_size are specific to the OSX |
| // and iOS allocators. |
| BatchMallocFn* const batch_malloc_function; |
| BatchFreeFn* const batch_free_function; |
| FreeDefiniteSizeFn* const free_definite_size_function; |
| // _aligned_malloc, _aligned_realloc, and _aligned_free are specific to the |
| // Windows allocator. |
| AlignedMallocFn* const aligned_malloc_function; |
| AlignedReallocFn* const aligned_realloc_function; |
| AlignedFreeFn* const aligned_free_function; |
| |
| const AllocatorDispatch* next; |
| |
| // |default_dispatch| is statically defined by one (and only one) of the |
| // allocator_shim_default_dispatch_to_*.cc files, depending on the build |
| // configuration. |
| static const AllocatorDispatch default_dispatch; |
| }; |
| |
| // When true makes malloc behave like new, w.r.t calling the new_handler if |
| // the allocation fails (see set_new_mode() in Windows). |
| BASE_EXPORT void SetCallNewHandlerOnMallocFailure(bool value); |
| |
| // Allocates |size| bytes or returns nullptr. It does NOT call the new_handler, |
| // regardless of SetCallNewHandlerOnMallocFailure(). |
| BASE_EXPORT void* UncheckedAlloc(size_t size); |
| |
| // Frees memory allocated with UncheckedAlloc(). |
| BASE_EXPORT void UncheckedFree(void* ptr); |
| |
| // Inserts |dispatch| in front of the allocator chain. This method is |
| // thread-safe w.r.t concurrent invocations of InsertAllocatorDispatch(). |
| // The callers have responsibility for inserting a single dispatch no more |
| // than once. |
| BASE_EXPORT void InsertAllocatorDispatch(AllocatorDispatch* dispatch); |
| |
| // Test-only. Rationale: (1) lack of use cases; (2) dealing safely with a |
| // removal of arbitrary elements from a singly linked list would require a lock |
| // in malloc(), which we really don't want. |
| BASE_EXPORT void RemoveAllocatorDispatchForTesting(AllocatorDispatch* dispatch); |
| |
| #if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) && BUILDFLAG(IS_WIN) |
| // Configures the allocator for the caller's allocation domain. Allocations that |
| // take place prior to this configuration step will succeed, but will not |
| // benefit from its one-time mitigations. As such, this function must be called |
| // as early as possible during startup. |
| BASE_EXPORT void ConfigurePartitionAlloc(); |
| #endif // BUILDFLAG(IS_WIN) |
| |
| #if BUILDFLAG(IS_APPLE) |
| #if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) |
| void InitializeDefaultAllocatorPartitionRoot(); |
| #endif // BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) |
| // On macOS, the allocator shim needs to be turned on during runtime. |
| BASE_EXPORT void InitializeAllocatorShim(); |
| #endif // BUILDFLAG(IS_APPLE) |
| |
| #if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) |
| BASE_EXPORT void EnablePartitionAllocMemoryReclaimer(); |
| |
| using EnableBrp = base::StrongAlias<class EnableBrpTag, bool>; |
| using EnableBrpZapping = base::StrongAlias<class EnableBrpZappingTag, bool>; |
| using SplitMainPartition = base::StrongAlias<class SplitMainPartitionTag, bool>; |
| using UseDedicatedAlignedPartition = |
| base::StrongAlias<class UseDedicatedAlignedPartitionTag, bool>; |
| using AlternateBucketDistribution = |
| base::StrongAlias<class AlternateBucketDistributionTag, bool>; |
| |
| // If |thread_cache_on_non_quarantinable_partition| is specified, the |
| // thread-cache will be enabled on the non-quarantinable partition. The |
| // thread-cache on the main (malloc) partition will be disabled. |
| BASE_EXPORT void ConfigurePartitions( |
| EnableBrp enable_brp, |
| EnableBrpZapping enable_brp_zapping, |
| SplitMainPartition split_main_partition, |
| UseDedicatedAlignedPartition use_dedicated_aligned_partition, |
| AlternateBucketDistribution use_alternate_bucket_distribution); |
| |
| #if defined(PA_ALLOW_PCSCAN) |
| BASE_EXPORT void EnablePCScan(partition_alloc::internal::PCScan::InitConfig); |
| #endif |
| #endif // BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) |
| |
| } // namespace allocator |
| } // namespace base |
| |
| #endif // BASE_ALLOCATOR_ALLOCATOR_SHIM_H_ |