diff options
Diffstat (limited to 'absl/base/internal/malloc_hook_mmap_linux.inc')
| -rw-r--r-- | absl/base/internal/malloc_hook_mmap_linux.inc | 96 |
1 files changed, 14 insertions, 82 deletions
diff --git a/absl/base/internal/malloc_hook_mmap_linux.inc b/absl/base/internal/malloc_hook_mmap_linux.inc index 059ded57..b87621a6 100644 --- a/absl/base/internal/malloc_hook_mmap_linux.inc +++ b/absl/base/internal/malloc_hook_mmap_linux.inc @@ -35,89 +35,18 @@ #include <cstdarg> #include <cstdint> -#ifdef __mips__ -// Include definitions of the ABI currently in use. -#ifdef __BIONIC__ -// Android doesn't have sgidefs.h, but does have asm/sgidefs.h, which has the -// definitions we need. -#include <asm/sgidefs.h> -#else -#include <sgidefs.h> -#endif // __BIONIC__ -#endif // __mips__ +#include "absl/base/internal/direct_mmap.h" -// SYS_mmap, SYS_munmap, and SYS_mremap are not defined in Android. +// SYS_mremap is not defined in Android. #ifdef __BIONIC__ -extern "C" void *__mmap2(void *, size_t, int, int, int, long); -#if defined(__NR_mmap) && !defined(SYS_mmap) -#define SYS_mmap __NR_mmap -#endif -#ifndef SYS_munmap -#define SYS_munmap __NR_munmap -#endif #ifndef SYS_mremap #define SYS_mremap __NR_mremap #endif #endif // __BIONIC__ -// Platform specific logic extracted from -// https://chromium.googlesource.com/linux-syscall-support/+/master/linux_syscall_support.h -static inline void* do_mmap64(void* start, size_t length, int prot, - int flags, int fd, off64_t offset) __THROW { -#if defined(__i386__) || \ - defined(__ARM_ARCH_3__) || defined(__ARM_EABI__) || \ - (defined(__mips__) && _MIPS_SIM == _MIPS_SIM_ABI32) || \ - (defined(__PPC__) && !defined(__PPC64__)) || \ - (defined(__s390__) && !defined(__s390x__)) - // On these architectures, implement mmap with mmap2. - static int pagesize = 0; - if (pagesize == 0) { - pagesize = getpagesize(); - } - if (offset < 0 || offset % pagesize != 0) { - errno = EINVAL; - return MAP_FAILED; - } -#ifdef __BIONIC__ - // SYS_mmap2 has problems on Android API level <= 16. - // Workaround by invoking __mmap2() instead. - return __mmap2(start, length, prot, flags, fd, offset / pagesize); -#else - return reinterpret_cast<void*>( - syscall(SYS_mmap2, start, length, prot, flags, fd, - static_cast<off_t>(offset / pagesize))); -#endif -#elif defined(__s390x__) - // On s390x, mmap() arguments are passed in memory. - uint32_t buf[6] = { - reinterpret_cast<uint32_t>(start), static_cast<uint32_t>(length), - static_cast<uint32_t>(prot), static_cast<uint32_t>(flags), - static_cast<uint32_t>(fd), static_cast<uint32_t>(offset)}; - return reintrepret_cast<void*>(syscall(SYS_mmap, buf)); -#elif defined(__x86_64__) - // The x32 ABI has 32 bit longs, but the syscall interface is 64 bit. - // We need to explicitly cast to an unsigned 64 bit type to avoid implicit - // sign extension. We can't cast pointers directly because those are - // 32 bits, and gcc will dump ugly warnings about casting from a pointer - // to an integer of a different size. We also need to make sure __off64_t - // isn't truncated to 32-bits under x32. - #define MMAP_SYSCALL_ARG(x) ((uint64_t)(uintptr_t)(x)) - return reinterpret_cast<void*>( - syscall(SYS_mmap, MMAP_SYSCALL_ARG(start), MMAP_SYSCALL_ARG(length), - MMAP_SYSCALL_ARG(prot), MMAP_SYSCALL_ARG(flags), - MMAP_SYSCALL_ARG(fd), static_cast<uint64_t>(offset))); - #undef MMAP_SYSCALL_ARG -#else // Remaining 64-bit aritectures. - static_assert(sizeof(unsigned long) == 8, "Platform is not 64-bit"); - return reinterpret_cast<void*>( - syscall(SYS_mmap, start, length, prot, flags, fd, offset)); -#endif -} - -// We use do_mmap64 abstraction to put MallocHook::InvokeMmapHook -// calls right into mmap and mmap64, so that the stack frames in the caller's -// stack are at the same offsets for all the calls of memory allocating -// functions. +// We put MallocHook::InvokeMmapHook calls right into mmap and mmap64, so that +// the stack frames in the caller's stack are at the same offsets for all the +// calls of memory allocating functions. // Put all callers of MallocHook::Invoke* in this module into // malloc_hook section, @@ -148,7 +77,8 @@ extern "C" void* mmap64(void *start, size_t length, int prot, int flags, void *result; if (!absl::base_internal::MallocHook::InvokeMmapReplacement( start, length, prot, flags, fd, offset, &result)) { - result = do_mmap64(start, length, prot, flags, fd, offset); + result = absl::base_internal::DirectMmap(start, length, prot, flags, fd, + offset); } absl::base_internal::MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset); @@ -164,8 +94,9 @@ extern "C" void* mmap(void *start, size_t length, int prot, int flags, void *result; if (!absl::base_internal::MallocHook::InvokeMmapReplacement( start, length, prot, flags, fd, offset, &result)) { - result = do_mmap64(start, length, prot, flags, fd, - static_cast<size_t>(offset)); // avoid sign extension + result = absl::base_internal::DirectMmap( + start, length, prot, flags, fd, + static_cast<size_t>(offset)); // avoid sign extension } absl::base_internal::MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset); @@ -179,7 +110,7 @@ extern "C" int munmap(void* start, size_t length) __THROW { int result; if (!absl::base_internal::MallocHook::InvokeMunmapReplacement(start, length, &result)) { - result = syscall(SYS_munmap, start, length); + result = absl::base_internal::DirectMunmap(start, length); } return result; } @@ -219,7 +150,8 @@ namespace base_internal { void* result; if (!MallocHook::InvokeMmapReplacement( start, length, prot, flags, fd, offset, &result)) { - result = do_mmap64(start, length, prot, flags, fd, offset); + result = absl::base_internal::DirectMmap(start, length, prot, flags, fd, + offset); } return result; } @@ -227,7 +159,7 @@ namespace base_internal { /*static*/int MallocHook::UnhookedMUnmap(void *start, size_t length) { int result; if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) { - result = syscall(SYS_munmap, start, length); + result = absl::base_internal::DirectMunmap(start, length); } return result; } |