diff options
| -rw-r--r-- | lib/System/Unix/Memory.cpp | 50 | ||||
| -rw-r--r-- | lib/System/Unix/Memory.inc | 50 |
2 files changed, 100 insertions, 0 deletions
diff --git a/lib/System/Unix/Memory.cpp b/lib/System/Unix/Memory.cpp index cc461f15df..370b318955 100644 --- a/lib/System/Unix/Memory.cpp +++ b/lib/System/Unix/Memory.cpp @@ -12,9 +12,59 @@ //===----------------------------------------------------------------------===// #include "Unix.h" +#include "llvm/System/Process.h" + +#ifdef HAVE_SYS_MMAN_H +#include <sys/mman.h> +#endif namespace llvm { +/// AllocateRWXMemory - Allocate a slab of memory with read/write/execute +/// permissions. This is typically used for JIT applications where we want +/// to emit code to the memory then jump to it. Getting this type of memory +/// is very OS specific. +/// +MemoryBlock Memory::AllocateRWX(unsigned NumBytes) { + if (NumBytes == 0) return MemoryBlock(); + + long pageSize = Process::GetPageSize(); + unsigned NumPages = (NumBytes+pageSize-1)/pageSize; + + int fd = -1; +#ifdef NEED_DEV_ZERO_FOR_MMAP + static int zero_fd = open("/dev/zero", O_RDWR); + if (zero_fd == -1) { + ThrowErrno("Can't open /dev/zero device"); + } + fd = zero_fd; +#endif + + int flags = MAP_PRIVATE | +#ifdef HAVE_MMAP_ANONYMOUS + MAP_ANONYMOUS +#else + MAP_ANON +#endif + ; + void *pa = ::mmap(0, pageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC, + flags, fd, 0); + if (pa == MAP_FAILED) { + ThrowErrno("Can't allocate RWX Memory"); + } + MemoryBlock result; + result.Address = pa; + result.Size = NumPages*pageSize; + return result; +} + +void Memory::ReleaseRWX(MemoryBlock& M) { + if (M.Address == 0 || M.Size == 0) return; + if (0 != ::munmap(M.Address, M.Size)) { + ThrowErrno("Can't release RWX Memory"); + } +} + } // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab diff --git a/lib/System/Unix/Memory.inc b/lib/System/Unix/Memory.inc index cc461f15df..370b318955 100644 --- a/lib/System/Unix/Memory.inc +++ b/lib/System/Unix/Memory.inc @@ -12,9 +12,59 @@ //===----------------------------------------------------------------------===// #include "Unix.h" +#include "llvm/System/Process.h" + +#ifdef HAVE_SYS_MMAN_H +#include <sys/mman.h> +#endif namespace llvm { +/// AllocateRWXMemory - Allocate a slab of memory with read/write/execute +/// permissions. This is typically used for JIT applications where we want +/// to emit code to the memory then jump to it. Getting this type of memory +/// is very OS specific. +/// +MemoryBlock Memory::AllocateRWX(unsigned NumBytes) { + if (NumBytes == 0) return MemoryBlock(); + + long pageSize = Process::GetPageSize(); + unsigned NumPages = (NumBytes+pageSize-1)/pageSize; + + int fd = -1; +#ifdef NEED_DEV_ZERO_FOR_MMAP + static int zero_fd = open("/dev/zero", O_RDWR); + if (zero_fd == -1) { + ThrowErrno("Can't open /dev/zero device"); + } + fd = zero_fd; +#endif + + int flags = MAP_PRIVATE | +#ifdef HAVE_MMAP_ANONYMOUS + MAP_ANONYMOUS +#else + MAP_ANON +#endif + ; + void *pa = ::mmap(0, pageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC, + flags, fd, 0); + if (pa == MAP_FAILED) { + ThrowErrno("Can't allocate RWX Memory"); + } + MemoryBlock result; + result.Address = pa; + result.Size = NumPages*pageSize; + return result; +} + +void Memory::ReleaseRWX(MemoryBlock& M) { + if (M.Address == 0 || M.Size == 0) return; + if (0 != ::munmap(M.Address, M.Size)) { + ThrowErrno("Can't release RWX Memory"); + } +} + } // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab |