X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Frts%2FAdjustor.c;h=c6729163171fb5066c78d92bc67e61a136c6352f;hb=4b17256112ecbee54dd4437f29c711bbfae239c7;hp=da8951c0c23b49e6213e0a61ac9d17be6ca7e2e6;hpb=eb311572a2551ab83f3141f00a3639caa551b03a;p=ghc-hetmet.git diff --git a/ghc/rts/Adjustor.c b/ghc/rts/Adjustor.c index da8951c..c672916 100644 --- a/ghc/rts/Adjustor.c +++ b/ghc/rts/Adjustor.c @@ -34,8 +34,8 @@ An adjustor thunk differs from a C function pointer in one respect: when the code is through with it, it has to be freed in order to release Haskell and C resources. Failure to do so result in memory leaks on both the C and Haskell side. - */ + #include "PosixSource.h" #include "Rts.h" #include "RtsExternal.h" @@ -46,46 +46,48 @@ Haskell side. #include #endif -/* Heavily arch-specific, I'm afraid.. */ +#if defined(openbsd_TARGET_OS) +#include +#include +#include -typedef enum { - pageExecuteRead, - pageExecuteReadWrite -} pageMode; +/* no C99 header stdint.h on OpenBSD? */ +typedef unsigned long my_uintptr_t; +#endif + +/* Heavily arch-specific, I'm afraid.. */ /* - * Function: execPage() - * - * Set the executable bit on page containing addr. + * Allocate len bytes which are readable, writable, and executable. * - * TODO: Can the code span more than one page? If yes, we need to make two - * pages executable! + * ToDo: If this turns out to be a performance bottleneck, one could + * e.g. cache the last VirtualProtect/mprotect-ed region and do + * nothing in case of a cache hit. */ -static rtsBool -execPage (void* addr, pageMode mode) +static void* +mallocBytesRWX(int len) { -#if defined(i386_TARGET_ARCH) && defined(_WIN32) && 0 - SYSTEM_INFO sInfo; - DWORD dwOldProtect = 0; - - /* doesn't return a result, so presumably it can't fail... */ - GetSystemInfo(&sInfo); - - if ( VirtualProtect ( (void*)((unsigned long)addr & (sInfo.dwPageSize - 1)), - sInfo.dwPageSize, - ( mode == pageExecuteReadWrite ? PAGE_EXECUTE_READWRITE : PAGE_EXECUTE_READ), - &dwOldProtect) == 0 ) { -# if 1 - DWORD rc = GetLastError(); - prog_belch("execPage: failed to protect 0x%p; error=%lu; old protection: %lu\n", addr, rc, dwOldProtect); -# endif - return rtsFalse; - } - return rtsTrue; -#else - (void)addr; (void)mode; /* keep gcc -Wall happy */ - return rtsTrue; + void *addr = stgMallocBytes(len, "mallocBytesRWX"); +#if defined(i386_TARGET_ARCH) && defined(_WIN32) + /* This could be necessary for processors which distinguish between READ and + EXECUTE memory accesses, e.g. Itaniums. */ + DWORD dwOldProtect = 0; + if (VirtualProtect (addr, len, PAGE_EXECUTE_READWRITE, &dwOldProtect) == 0) { + barf("mallocBytesRWX: failed to protect 0x%p; error=%lu; old protection: %lu\n", + addr, (unsigned long)GetLastError(), (unsigned long)dwOldProtect); + } +#elif defined(openbsd_TARGET_OS) + /* malloced memory isn't executable by default on OpenBSD */ + my_uintptr_t pageSize = sysconf(_SC_PAGESIZE); + my_uintptr_t mask = ~(pageSize - 1); + my_uintptr_t startOfFirstPage = ((my_uintptr_t)addr ) & mask; + my_uintptr_t startOfLastPage = ((my_uintptr_t)addr + len - 1) & mask; + my_uintptr_t size = startOfLastPage - startOfFirstPage + pageSize; + if (mprotect((void*)startOfFirstPage, (size_t)size, PROT_EXEC | PROT_READ | PROT_WRITE) != 0) { + barf("mallocBytesRWX: failed to protect 0x%p\n", addr); + } #endif + return addr; } #if defined(i386_TARGET_ARCH) @@ -153,7 +155,7 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr) : ff e0 jmp %eax # and jump to it. # the callee cleans up the stack */ - adjustor = stgMallocBytes(14, "createAdjustor"); + adjustor = mallocBytesRWX(14); { unsigned char *const adj_code = (unsigned char *)adjustor; adj_code[0x00] = (unsigned char)0x58; /* popl %eax */ @@ -168,8 +170,6 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr) adj_code[0x0c] = (unsigned char)0xff; /* jmp %eax */ adj_code[0x0d] = (unsigned char)0xe0; - - execPage(adjustor, pageExecuteReadWrite); } #endif break; @@ -200,7 +200,7 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr) That's (thankfully) the case here with the restricted set of return types that we support. */ - adjustor = stgMallocBytes(17, "createAdjustor"); + adjustor = mallocBytesRWX(17); { unsigned char *const adj_code = (unsigned char *)adjustor; @@ -215,8 +215,6 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr) adj_code[0x0f] = (unsigned char)0xff; /* jmp *%eax */ adj_code[0x10] = (unsigned char)0xe0; - - execPage(adjustor, pageExecuteReadWrite); } #elif defined(sparc_TARGET_ARCH) /* Magic constant computed by inspecting the code length of the following @@ -248,7 +246,7 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr) similarly, and local variables should be accessed via %fp, not %sp. In a nutshell: This should work! (Famous last words! :-) */ - adjustor = stgMallocBytes(4*(11+1), "createAdjustor"); + adjustor = mallocBytesRWX(4*(11+1)); { unsigned long *const adj_code = (unsigned long *)adjustor; @@ -325,7 +323,7 @@ TODO: Depending on how much allocation overhead stgMallocBytes uses for 4 bytes (getting rid of the nop), hence saving memory. [ccshan] */ ASSERT(((StgWord64)wptr & 3) == 0); - adjustor = stgMallocBytes(48, "createAdjustor"); + adjustor = mallocBytesRWX(48); { StgWord64 *const code = (StgWord64 *)adjustor; @@ -363,7 +361,7 @@ TODO: Depending on how much allocation overhead stgMallocBytes uses for this code, it only works for up to 6 arguments (when floating point arguments are involved, this may be more or less, depending on the exact situation). */ - adjustor = stgMallocBytes(4*13, "createAdjustor"); + adjustor = mallocBytesRWX(4*13); { unsigned long *const adj_code = (unsigned long *)adjustor; @@ -506,7 +504,7 @@ freeHaskellFunctionPtr(void* ptr) #if defined(i386_TARGET_ARCH) if ( *(unsigned char*)ptr != 0x68 && *(unsigned char*)ptr != 0x58 ) { - prog_belch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); + errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); return; } @@ -518,7 +516,7 @@ freeHaskellFunctionPtr(void* ptr) } #elif defined(sparc_TARGET_ARCH) if ( *(unsigned long*)ptr != 0x9C23A008UL ) { - prog_belch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); + errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); return; } @@ -526,7 +524,7 @@ freeHaskellFunctionPtr(void* ptr) freeStablePtr(*((StgStablePtr*)((unsigned long*)ptr + 11))); #elif defined(alpha_TARGET_ARCH) if ( *(StgWord64*)ptr != 0xa77b0018a61b0010L ) { - prog_belch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); + errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); return; } @@ -534,7 +532,7 @@ freeHaskellFunctionPtr(void* ptr) freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x10))); #elif defined(powerpc_TARGET_ARCH) if ( *(StgWord*)ptr != 0x7d0a4378 ) { - prog_belch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); + errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); return; } freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 4*12))); @@ -543,7 +541,7 @@ freeHaskellFunctionPtr(void* ptr) StgWord64 *code = (StgWord64 *)(fdesc+1); if (fdesc->ip != (StgWord64)code) { - prog_belch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); + errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr); return; } freeStablePtr((StgStablePtr)code[16]); @@ -563,7 +561,7 @@ freeHaskellFunctionPtr(void* ptr) * * Perform initialisation of adjustor thunk layer (if needed.) */ -rtsBool +void initAdjustor(void) { #if defined(i386_TARGET_ARCH) @@ -584,15 +582,12 @@ initAdjustor(void) to return to it before tail jumping from the adjustor thunk. */ - obscure_ccall_ret_code = stgMallocBytes(4, "initAdjustor"); + obscure_ccall_ret_code = mallocBytesRWX(4); obscure_ccall_ret_code[0x00] = (unsigned char)0x83; /* addl $0x4, %esp */ obscure_ccall_ret_code[0x01] = (unsigned char)0xc4; obscure_ccall_ret_code[0x02] = (unsigned char)0x04; obscure_ccall_ret_code[0x03] = (unsigned char)0xc3; /* ret */ - - execPage(obscure_ccall_ret_code, pageExecuteRead); #endif - return rtsTrue; }