diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/aarch64/sysdep.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/aarch64/sysdep.h | 414 |
1 files changed, 414 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/aarch64/sysdep.h b/sysdeps/unix/sysv/linux/aarch64/sysdep.h new file mode 100644 index 0000000000..5ccf1da18b --- /dev/null +++ b/sysdeps/unix/sysv/linux/aarch64/sysdep.h @@ -0,0 +1,414 @@ +/* Copyright (C) 2005-2014 Free Software Foundation, Inc. + + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _LINUX_AARCH64_SYSDEP_H +#define _LINUX_AARCH64_SYSDEP_H 1 + +#include <sysdeps/unix/sysdep.h> +#include <sysdeps/aarch64/sysdep.h> +#include <sysdeps/unix/sysv/linux/generic/sysdep.h> + +/* Defines RTLD_PRIVATE_ERRNO and USE_DL_SYSINFO. */ +#include <dl-sysdep.h> + +#include <tls.h> + +/* In order to get __set_errno() definition in INLINE_SYSCALL. */ +#ifndef __ASSEMBLER__ +#include <errno.h> +#endif + +/* For Linux we can use the system call table in the header file + /usr/include/asm/unistd.h + of the kernel. But these symbols do not follow the SYS_* syntax + so we have to redefine the `SYS_ify' macro here. */ +#undef SYS_ify +#define SYS_ify(syscall_name) (__NR_##syscall_name) + +#ifdef __ASSEMBLER__ + +/* Linux uses a negative return value to indicate syscall errors, + unlike most Unices, which use the condition codes' carry flag. + + Since version 2.1 the return value of a system call might be + negative even if the call succeeded. E.g., the `lseek' system call + might return a large offset. Therefore we must not anymore test + for < 0, but test for a real error by making sure the value in R0 + is a real error number. Linus said he will make sure the no syscall + returns a value in -1 .. -4095 as a valid result so we can safely + test with -4095. */ + +# undef PSEUDO +# define PSEUDO(name, syscall_name, args) \ + .text; \ + ENTRY (name); \ + DO_CALL (syscall_name, args); \ + cmn x0, #4095; + +/* Notice the use of 'RET' instead of 'ret' the assembler is case + insensitive and eglibc already uses the preprocessor symbol 'ret' + so we use the upper case 'RET' to force through a ret instruction + to the assembler */ +# define PSEUDO_RET \ + b.cs 1f; \ + RET; \ + 1: \ + b SYSCALL_ERROR +# undef ret +# define ret PSEUDO_RET + +# undef PSEUDO_END +# define PSEUDO_END(name) \ + SYSCALL_ERROR_HANDLER \ + END (name) + +# undef PSEUDO_NOERRNO +# define PSEUDO_NOERRNO(name, syscall_name, args) \ + .text; \ + ENTRY (name); \ + DO_CALL (syscall_name, args); + +/* Notice the use of 'RET' instead of 'ret' the assembler is case + insensitive and eglibc already uses the preprocessor symbol 'ret' + so we use the upper case 'RET' to force through a ret instruction + to the assembler */ +# define PSEUDO_RET_NOERRNO \ + RET; + +# undef ret_NOERRNO +# define ret_NOERRNO PSEUDO_RET_NOERRNO + +# undef PSEUDO_END_NOERRNO +# define PSEUDO_END_NOERRNO(name) \ + END (name) + +/* The function has to return the error code. */ +# undef PSEUDO_ERRVAL +# define PSEUDO_ERRVAL(name, syscall_name, args) \ + .text; \ + ENTRY (name) \ + DO_CALL (syscall_name, args); \ + neg x0, x0 + +# undef PSEUDO_END_ERRVAL +# define PSEUDO_END_ERRVAL(name) \ + END (name) + +# define ret_ERRVAL PSEUDO_RET_NOERRNO + +# if NOT_IN_libc +# define SYSCALL_ERROR __local_syscall_error +# if RTLD_PRIVATE_ERRNO +# define SYSCALL_ERROR_HANDLER \ +__local_syscall_error: \ + adrp x1, C_SYMBOL_NAME(rtld_errno); \ + add x1, x1, #:lo12:C_SYMBOL_NAME(rtld_errno); \ + neg w0, w0; \ + str w0, [x1]; \ + mov x0, -1; \ + RET; +# else + +# define SYSCALL_ERROR_HANDLER \ +__local_syscall_error: \ + stp x29, x30, [sp, -32]!; \ + cfi_adjust_cfa_offset (32); \ + cfi_rel_offset (x29, 0); \ + cfi_rel_offset (x30, 8); \ + add x29, sp, 0; \ + str x19, [sp,16]; \ + neg x19, x0; \ + bl C_SYMBOL_NAME(__errno_location); \ + str w19, [x0]; \ + mov x0, -1; \ + ldr x19, [sp,16]; \ + ldp x29, x30, [sp], 32; \ + cfi_adjust_cfa_offset (-32); \ + cfi_restore (x29); \ + cfi_restore (x30); \ + RET; +# endif +# else +# define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */ +# define SYSCALL_ERROR __syscall_error +# endif + +/* Linux takes system call args in registers: + syscall number in the SVC instruction + arg 1 x0 + arg 2 x1 + arg 3 x2 + arg 4 x3 + arg 5 x4 + arg 6 x5 + arg 7 x6 + + The compiler is going to form a call by coming here, through PSEUDO, with + arguments + syscall number in the DO_CALL macro + arg 1 x0 + arg 2 x1 + arg 3 x2 + arg 4 x3 + arg 5 x4 + arg 6 x5 + arg 7 x6 + + We need to shuffle values between R4..R6 and the stack so that the + caller's v1..v3 and stack frame are not corrupted, and the kernel + sees the right arguments. + +*/ + +# undef DO_CALL +# define DO_CALL(syscall_name, args) \ + DOARGS_##args \ + mov x8, SYS_ify (syscall_name); \ + svc 0; \ + UNDOARGS_##args + +# define DOARGS_0 /* nothing */ +# define DOARGS_1 /* nothing */ +# define DOARGS_2 /* nothing */ +# define DOARGS_3 /* nothing */ +# define DOARGS_4 /* nothing */ +# define DOARGS_5 /* nothing */ +# define DOARGS_6 /* nothing */ +# define DOARGS_7 /* nothing */ + +# define UNDOARGS_0 /* nothing */ +# define UNDOARGS_1 /* nothing */ +# define UNDOARGS_2 /* nothing */ +# define UNDOARGS_3 /* nothing */ +# define UNDOARGS_4 /* nothing */ +# define UNDOARGS_5 /* nothing */ +# define UNDOARGS_6 /* nothing */ +# define UNDOARGS_7 /* nothing */ + +#else /* not __ASSEMBLER__ */ + +# ifdef SHARED +# define INLINE_VSYSCALL(name, nr, args...) \ + ({ \ + __label__ out; \ + __label__ iserr; \ + long sc_ret; \ + INTERNAL_SYSCALL_DECL (sc_err); \ + \ + if (__vdso_##name != NULL) \ + { \ + sc_ret = INTERNAL_VSYSCALL_NCS (__vdso_##name, sc_err, nr, ##args); \ + if (!INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err)) \ + goto out; \ + if (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err) != ENOSYS) \ + goto iserr; \ + } \ + \ + sc_ret = INTERNAL_SYSCALL (name, sc_err, nr, ##args); \ + if (INTERNAL_SYSCALL_ERROR_P (sc_ret, sc_err)) \ + { \ + iserr: \ + __set_errno (INTERNAL_SYSCALL_ERRNO (sc_ret, sc_err)); \ + sc_ret = -1L; \ + } \ + out: \ + sc_ret; \ + }) +# else +# define INLINE_VSYSCALL(name, nr, args...) \ + INLINE_SYSCALL (name, nr, ##args) +# endif + +# ifdef SHARED +# define INTERNAL_VSYSCALL(name, err, nr, args...) \ + ({ \ + __label__ out; \ + long v_ret; \ + \ + if (__vdso_##name != NULL) \ + { \ + v_ret = INTERNAL_VSYSCALL_NCS (__vdso_##name, err, nr, ##args); \ + if (!INTERNAL_SYSCALL_ERROR_P (v_ret, err) \ + || INTERNAL_SYSCALL_ERRNO (v_ret, err) != ENOSYS) \ + goto out; \ + } \ + v_ret = INTERNAL_SYSCALL (name, err, nr, ##args); \ + out: \ + v_ret; \ + }) +# else +# define INTERNAL_VSYSCALL(name, err, nr, args...) \ + INTERNAL_SYSCALL (name, err, nr, ##args) +# endif + +/* List of system calls which are supported as vsyscalls. */ +# define HAVE_CLOCK_GETRES_VSYSCALL 1 +# define HAVE_CLOCK_GETTIME_VSYSCALL 1 + +# define INTERNAL_VSYSCALL_NCS(funcptr, err, nr, args...) \ + ({ \ + LOAD_ARGS_##nr (args) \ + asm volatile ("blr %1" \ + : "=r" (_x0) \ + : "r" (funcptr), ASM_ARGS_##nr \ + : "x30", "memory"); \ + (long) _x0; \ + }) + + +/* Define a macro which expands into the inline wrapper code for a system + call. */ +# undef INLINE_SYSCALL +# define INLINE_SYSCALL(name, nr, args...) \ + ({ unsigned long _sys_result = INTERNAL_SYSCALL (name, , nr, args); \ + if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_sys_result, ), 0))\ + { \ + __set_errno (INTERNAL_SYSCALL_ERRNO (_sys_result, )); \ + _sys_result = (unsigned long) -1; \ + } \ + (long) _sys_result; }) + +# undef INTERNAL_SYSCALL_DECL +# define INTERNAL_SYSCALL_DECL(err) do { } while (0) + +# undef INTERNAL_SYSCALL_RAW +# define INTERNAL_SYSCALL_RAW(name, err, nr, args...) \ + ({ unsigned long _sys_result; \ + { \ + LOAD_ARGS_##nr (args) \ + register long _x8 asm ("x8") = (name); \ + asm volatile ("svc 0 // syscall " # name \ + : "+r" (_x0), "+r" (_x8) \ + : ASM_ARGS_##nr \ + : "memory", CLOBBER_ARGS_##nr); \ + _sys_result = _x0; \ + } \ + (long) _sys_result; }) + +# undef INTERNAL_SYSCALL +# define INTERNAL_SYSCALL(name, err, nr, args...) \ + INTERNAL_SYSCALL_RAW(SYS_ify(name), err, nr, args) + +# undef INTERNAL_SYSCALL_AARCH64 +# define INTERNAL_SYSCALL_AARCH64(name, err, nr, args...) \ + INTERNAL_SYSCALL_RAW(__ARM_NR_##name, err, nr, args) + +# undef INTERNAL_SYSCALL_ERROR_P +# define INTERNAL_SYSCALL_ERROR_P(val, err) \ + ((unsigned long) (val) >= (unsigned long) -4095) + +# undef INTERNAL_SYSCALL_ERRNO +# define INTERNAL_SYSCALL_ERRNO(val, err) (-(val)) + +# define CLOBBER_ARGS_0 CLOBBER_ARGS_1 +# define CLOBBER_ARGS_1 "x1", CLOBBER_ARGS_2 +# define CLOBBER_ARGS_2 "x2", CLOBBER_ARGS_3 +# define CLOBBER_ARGS_3 "x3", CLOBBER_ARGS_4 +# define CLOBBER_ARGS_4 "x4", CLOBBER_ARGS_5 +# define CLOBBER_ARGS_5 "x5", CLOBBER_ARGS_6 +# define CLOBBER_ARGS_6 "x6", CLOBBER_ARGS_7 +# define CLOBBER_ARGS_7 \ + "x7", "x9", "x10", "x11", "x12", "x13", "x14", "x15", "x16", "x17", "x18" + +# define LOAD_ARGS_0() \ + register long _x0 asm ("x0"); + +# define ASM_ARGS_0 +# define LOAD_ARGS_1(x0) \ + long _x0tmp = (long) (x0); \ + LOAD_ARGS_0 () \ + _x0 = _x0tmp; +# define ASM_ARGS_1 "r" (_x0) +# define LOAD_ARGS_2(x0, x1) \ + long _x1tmp = (long) (x1); \ + LOAD_ARGS_1 (x0) \ + register long _x1 asm ("x1") = _x1tmp; +# define ASM_ARGS_2 ASM_ARGS_1, "r" (_x1) +# define LOAD_ARGS_3(x0, x1, x2) \ + long _x2tmp = (long) (x2); \ + LOAD_ARGS_2 (x0, x1) \ + register long _x2 asm ("x2") = _x2tmp; +# define ASM_ARGS_3 ASM_ARGS_2, "r" (_x2) +# define LOAD_ARGS_4(x0, x1, x2, x3) \ + long _x3tmp = (long) (x3); \ + LOAD_ARGS_3 (x0, x1, x2) \ + register long _x3 asm ("x3") = _x3tmp; +# define ASM_ARGS_4 ASM_ARGS_3, "r" (_x3) +# define LOAD_ARGS_5(x0, x1, x2, x3, x4) \ + long _x4tmp = (long) (x4); \ + LOAD_ARGS_4 (x0, x1, x2, x3) \ + register long _x4 asm ("x4") = _x4tmp; +# define ASM_ARGS_5 ASM_ARGS_4, "r" (_x4) +# define LOAD_ARGS_6(x0, x1, x2, x3, x4, x5) \ + long _x5tmp = (long) (x5); \ + LOAD_ARGS_5 (x0, x1, x2, x3, x4) \ + register long _x5 asm ("x5") = _x5tmp; +# define ASM_ARGS_6 ASM_ARGS_5, "r" (_x5) +# define LOAD_ARGS_7(x0, x1, x2, x3, x4, x5, x6)\ + long _x6tmp = (long) (x6); \ + LOAD_ARGS_6 (x0, x1, x2, x3, x4, x5) \ + register long _x6 asm ("x6") = _x6tmp; +# define ASM_ARGS_7 ASM_ARGS_6, "r" (_x6) + +# undef INTERNAL_SYSCALL_NCS +# define INTERNAL_SYSCALL_NCS(number, err, nr, args...) \ + INTERNAL_SYSCALL_RAW (number, err, nr, args) + +#endif /* __ASSEMBLER__ */ + +/* Pointer mangling is supported for AArch64. */ +#if (defined NOT_IN_libc && defined IS_IN_rtld) || \ + (!defined SHARED && (!defined NOT_IN_libc || defined IS_IN_libpthread)) +# ifdef __ASSEMBLER__ +# define PTR_MANGLE(dst, src, guard, tmp) \ + LDST_PCREL (ldr, guard, tmp, C_SYMBOL_NAME(__pointer_chk_guard_local)); \ + PTR_MANGLE2 (dst, src, guard) +/* Use PTR_MANGLE2 for efficiency if guard is already loaded. */ +# define PTR_MANGLE2(dst, src, guard)\ + eor dst, src, guard +# define PTR_DEMANGLE(dst, src, guard, tmp)\ + PTR_MANGLE (dst, src, guard, tmp) +# define PTR_DEMANGLE2(dst, src, guard)\ + PTR_MANGLE2 (dst, src, guard) +# else +extern uintptr_t __pointer_chk_guard_local attribute_relro attribute_hidden; +# define PTR_MANGLE(var) \ + (var) = (__typeof (var)) ((uintptr_t) (var) ^ __pointer_chk_guard_local) +# define PTR_DEMANGLE(var) PTR_MANGLE (var) +# endif +#else +# ifdef __ASSEMBLER__ +# define PTR_MANGLE(dst, src, guard, tmp) \ + LDST_GLOBAL (ldr, guard, tmp, C_SYMBOL_NAME(__pointer_chk_guard)); \ + PTR_MANGLE2 (dst, src, guard) +/* Use PTR_MANGLE2 for efficiency if guard is already loaded. */ +# define PTR_MANGLE2(dst, src, guard)\ + eor dst, src, guard +# define PTR_DEMANGLE(dst, src, guard, tmp)\ + PTR_MANGLE (dst, src, guard, tmp) +# define PTR_DEMANGLE2(dst, src, guard)\ + PTR_MANGLE2 (dst, src, guard) +# else +extern uintptr_t __pointer_chk_guard attribute_relro; +# define PTR_MANGLE(var) \ + (var) = (__typeof (var)) ((uintptr_t) (var) ^ __pointer_chk_guard) +# define PTR_DEMANGLE(var) PTR_MANGLE (var) +# endif +#endif + +#endif /* linux/aarch64/sysdep.h */ |