| /* Copyright (C) 2001-2018 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_X86_64_SYSDEP_H |
| #define _LINUX_X86_64_SYSDEP_H 1 |
| |
| /* There is some commonality. */ |
| #include <sysdeps/unix/sysv/linux/sysdep.h> |
| #include <sysdeps/unix/x86_64/sysdep.h> |
| #include <tls.h> |
| |
| #if IS_IN (rtld) |
| # include <dl-sysdep.h> /* Defines RTLD_PRIVATE_ERRNO. */ |
| #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 |
| |
| /* This is a kludge to make syscalls.list find these under the names |
| pread and pwrite, since some kernel headers define those names |
| and some define the *64 names for the same system calls. */ |
| #if !defined __NR_pread && defined __NR_pread64 |
| # define __NR_pread __NR_pread64 |
| #endif |
| #if !defined __NR_pwrite && defined __NR_pwrite64 |
| # define __NR_pwrite __NR_pwrite64 |
| #endif |
| |
| /* This is to help the old kernel headers where __NR_semtimedop is not |
| available. */ |
| #ifndef __NR_semtimedop |
| # define __NR_semtimedop 220 |
| #endif |
| |
| |
| #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 %eax |
| 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 savely |
| test with -4095. */ |
| |
| /* We don't want the label for the error handle to be global when we define |
| it here. */ |
| # ifdef PIC |
| # define SYSCALL_ERROR_LABEL 0f |
| # else |
| # define SYSCALL_ERROR_LABEL syscall_error |
| # endif |
| |
| # undef PSEUDO |
| # define PSEUDO(name, syscall_name, args) \ |
| .text; \ |
| ENTRY (name) \ |
| DO_CALL (syscall_name, args); \ |
| cmpq $-4095, %rax; \ |
| jae SYSCALL_ERROR_LABEL |
| |
| # 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) |
| |
| # undef PSEUDO_END_NOERRNO |
| # define PSEUDO_END_NOERRNO(name) \ |
| END (name) |
| |
| # define ret_NOERRNO ret |
| |
| # undef PSEUDO_ERRVAL |
| # define PSEUDO_ERRVAL(name, syscall_name, args) \ |
| .text; \ |
| ENTRY (name) \ |
| DO_CALL (syscall_name, args); \ |
| negq %rax |
| |
| # undef PSEUDO_END_ERRVAL |
| # define PSEUDO_END_ERRVAL(name) \ |
| END (name) |
| |
| # define ret_ERRVAL ret |
| |
| # if defined PIC && defined RTLD_PRIVATE_ERRNO |
| # define SYSCALL_SET_ERRNO \ |
| lea rtld_errno(%rip), %RCX_LP; \ |
| neg %eax; \ |
| movl %eax, (%rcx) |
| # else |
| # if IS_IN (libc) |
| # define SYSCALL_ERROR_ERRNO __libc_errno |
| # else |
| # define SYSCALL_ERROR_ERRNO errno |
| # endif |
| # define SYSCALL_SET_ERRNO \ |
| movq SYSCALL_ERROR_ERRNO@GOTTPOFF(%rip), %rcx;\ |
| neg %eax; \ |
| movl %eax, %fs:(%rcx); |
| # endif |
| |
| # ifndef PIC |
| # define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */ |
| # else |
| # define SYSCALL_ERROR_HANDLER \ |
| 0: \ |
| SYSCALL_SET_ERRNO; \ |
| or $-1, %RAX_LP; \ |
| ret; |
| # endif /* PIC */ |
| |
| /* The Linux/x86-64 kernel expects the system call parameters in |
| registers according to the following table: |
| |
| syscall number rax |
| arg 1 rdi |
| arg 2 rsi |
| arg 3 rdx |
| arg 4 r10 |
| arg 5 r8 |
| arg 6 r9 |
| |
| The Linux kernel uses and destroys internally these registers: |
| return address from |
| syscall rcx |
| eflags from syscall r11 |
| |
| Normal function call, including calls to the system call stub |
| functions in the libc, get the first six parameters passed in |
| registers and the seventh parameter and later on the stack. The |
| register use is as follows: |
| |
| system call number in the DO_CALL macro |
| arg 1 rdi |
| arg 2 rsi |
| arg 3 rdx |
| arg 4 rcx |
| arg 5 r8 |
| arg 6 r9 |
| |
| We have to take care that the stack is aligned to 16 bytes. When |
| called the stack is not aligned since the return address has just |
| been pushed. |
| |
| |
| Syscalls of more than 6 arguments are not supported. */ |
| |
| # undef DO_CALL |
| # define DO_CALL(syscall_name, args) \ |
| DOARGS_##args \ |
| movl $SYS_ify (syscall_name), %eax; \ |
| syscall; |
| |
| # define DOARGS_0 /* nothing */ |
| # define DOARGS_1 /* nothing */ |
| # define DOARGS_2 /* nothing */ |
| # define DOARGS_3 /* nothing */ |
| # define DOARGS_4 movq %rcx, %r10; |
| # define DOARGS_5 DOARGS_4 |
| # define DOARGS_6 DOARGS_5 |
| |
| #else /* !__ASSEMBLER__ */ |
| /* Define a macro which expands inline into the wrapper code for a system |
| call. */ |
| # undef INLINE_SYSCALL |
| # define INLINE_SYSCALL(name, nr, args...) \ |
| ({ \ |
| unsigned long int resultvar = INTERNAL_SYSCALL (name, , nr, args); \ |
| if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (resultvar, ))) \ |
| { \ |
| __set_errno (INTERNAL_SYSCALL_ERRNO (resultvar, )); \ |
| resultvar = (unsigned long int) -1; \ |
| } \ |
| (long int) resultvar; }) |
| |
| /* Define a macro with explicit types for arguments, which expands inline |
| into the wrapper code for a system call. It should be used when size |
| of any argument > size of long int. */ |
| # undef INLINE_SYSCALL_TYPES |
| # define INLINE_SYSCALL_TYPES(name, nr, args...) \ |
| ({ \ |
| unsigned long int resultvar = INTERNAL_SYSCALL_TYPES (name, , nr, args); \ |
| if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (resultvar, ))) \ |
| { \ |
| __set_errno (INTERNAL_SYSCALL_ERRNO (resultvar, )); \ |
| resultvar = (unsigned long int) -1; \ |
| } \ |
| (long int) resultvar; }) |
| |
| # undef INTERNAL_SYSCALL_DECL |
| # define INTERNAL_SYSCALL_DECL(err) do { } while (0) |
| |
| /* Registers clobbered by syscall. */ |
| # define REGISTERS_CLOBBERED_BY_SYSCALL "cc", "r11", "cx" |
| |
| /* Create a variable 'name' based on type 'X' to avoid explicit types. |
| This is mainly used set use 64-bits arguments in x32. */ |
| #define TYPEFY(X, name) __typeof__ ((X) - (X)) name |
| /* Explicit cast the argument to avoid integer from pointer warning on |
| x32. */ |
| #define ARGIFY(X) ((__typeof__ ((X) - (X))) (X)) |
| |
| #undef INTERNAL_SYSCALL |
| #define INTERNAL_SYSCALL(name, err, nr, args...) \ |
| internal_syscall##nr (SYS_ify (name), err, args) |
| |
| #undef INTERNAL_SYSCALL_NCS |
| #define INTERNAL_SYSCALL_NCS(number, err, nr, args...) \ |
| internal_syscall##nr (number, err, args) |
| |
| #undef internal_syscall0 |
| #define internal_syscall0(number, err, dummy...) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall1 |
| #define internal_syscall1(number, err, arg1) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall2 |
| #define internal_syscall2(number, err, arg1, arg2) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg2, __arg2) = ARGIFY (arg2); \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1), "r" (_a2) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall3 |
| #define internal_syscall3(number, err, arg1, arg2, arg3) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg3, __arg3) = ARGIFY (arg3); \ |
| TYPEFY (arg2, __arg2) = ARGIFY (arg2); \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ |
| register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1), "r" (_a2), "r" (_a3) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall4 |
| #define internal_syscall4(number, err, arg1, arg2, arg3, arg4) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg4, __arg4) = ARGIFY (arg4); \ |
| TYPEFY (arg3, __arg3) = ARGIFY (arg3); \ |
| TYPEFY (arg2, __arg2) = ARGIFY (arg2); \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg4, _a4) asm ("r10") = __arg4; \ |
| register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ |
| register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1), "r" (_a2), "r" (_a3), "r" (_a4) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall5 |
| #define internal_syscall5(number, err, arg1, arg2, arg3, arg4, arg5) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg5, __arg5) = ARGIFY (arg5); \ |
| TYPEFY (arg4, __arg4) = ARGIFY (arg4); \ |
| TYPEFY (arg3, __arg3) = ARGIFY (arg3); \ |
| TYPEFY (arg2, __arg2) = ARGIFY (arg2); \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg5, _a5) asm ("r8") = __arg5; \ |
| register TYPEFY (arg4, _a4) asm ("r10") = __arg4; \ |
| register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ |
| register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1), "r" (_a2), "r" (_a3), "r" (_a4), \ |
| "r" (_a5) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| #undef internal_syscall6 |
| #define internal_syscall6(number, err, arg1, arg2, arg3, arg4, arg5, arg6) \ |
| ({ \ |
| unsigned long int resultvar; \ |
| TYPEFY (arg6, __arg6) = ARGIFY (arg6); \ |
| TYPEFY (arg5, __arg5) = ARGIFY (arg5); \ |
| TYPEFY (arg4, __arg4) = ARGIFY (arg4); \ |
| TYPEFY (arg3, __arg3) = ARGIFY (arg3); \ |
| TYPEFY (arg2, __arg2) = ARGIFY (arg2); \ |
| TYPEFY (arg1, __arg1) = ARGIFY (arg1); \ |
| register TYPEFY (arg6, _a6) asm ("r9") = __arg6; \ |
| register TYPEFY (arg5, _a5) asm ("r8") = __arg5; \ |
| register TYPEFY (arg4, _a4) asm ("r10") = __arg4; \ |
| register TYPEFY (arg3, _a3) asm ("rdx") = __arg3; \ |
| register TYPEFY (arg2, _a2) asm ("rsi") = __arg2; \ |
| register TYPEFY (arg1, _a1) asm ("rdi") = __arg1; \ |
| asm volatile ( \ |
| "syscall\n\t" \ |
| : "=a" (resultvar) \ |
| : "0" (number), "r" (_a1), "r" (_a2), "r" (_a3), "r" (_a4), \ |
| "r" (_a5), "r" (_a6) \ |
| : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \ |
| (long int) resultvar; \ |
| }) |
| |
| # undef INTERNAL_SYSCALL_ERROR_P |
| # define INTERNAL_SYSCALL_ERROR_P(val, err) \ |
| ((unsigned long int) (long int) (val) >= -4095L) |
| |
| # undef INTERNAL_SYSCALL_ERRNO |
| # define INTERNAL_SYSCALL_ERRNO(val, err) (-(val)) |
| |
| /* List of system calls which are supported as vsyscalls. */ |
| # define HAVE_CLOCK_GETTIME_VSYSCALL 1 |
| # define HAVE_GETTIMEOFDAY_VSYSCALL 1 |
| # define HAVE_GETCPU_VSYSCALL 1 |
| |
| # define SINGLE_THREAD_BY_GLOBAL 1 |
| |
| #endif /* __ASSEMBLER__ */ |
| |
| |
| /* Pointer mangling support. */ |
| #if IS_IN (rtld) |
| /* We cannot use the thread descriptor because in ld.so we use setjmp |
| earlier than the descriptor is initialized. */ |
| # ifdef __ASSEMBLER__ |
| # define PTR_MANGLE(reg) xor __pointer_chk_guard_local(%rip), reg; \ |
| rol $2*LP_SIZE+1, reg |
| # define PTR_DEMANGLE(reg) ror $2*LP_SIZE+1, reg; \ |
| xor __pointer_chk_guard_local(%rip), reg |
| # else |
| # define PTR_MANGLE(reg) asm ("xor __pointer_chk_guard_local(%%rip), %0\n" \ |
| "rol $2*" LP_SIZE "+1, %0" \ |
| : "=r" (reg) : "0" (reg)) |
| # define PTR_DEMANGLE(reg) asm ("ror $2*" LP_SIZE "+1, %0\n" \ |
| "xor __pointer_chk_guard_local(%%rip), %0" \ |
| : "=r" (reg) : "0" (reg)) |
| # endif |
| #else |
| # ifdef __ASSEMBLER__ |
| # define PTR_MANGLE(reg) xor %fs:POINTER_GUARD, reg; \ |
| rol $2*LP_SIZE+1, reg |
| # define PTR_DEMANGLE(reg) ror $2*LP_SIZE+1, reg; \ |
| xor %fs:POINTER_GUARD, reg |
| # else |
| # define PTR_MANGLE(var) asm ("xor %%fs:%c2, %0\n" \ |
| "rol $2*" LP_SIZE "+1, %0" \ |
| : "=r" (var) \ |
| : "0" (var), \ |
| "i" (offsetof (tcbhead_t, \ |
| pointer_guard))) |
| # define PTR_DEMANGLE(var) asm ("ror $2*" LP_SIZE "+1, %0\n" \ |
| "xor %%fs:%c2, %0" \ |
| : "=r" (var) \ |
| : "0" (var), \ |
| "i" (offsetof (tcbhead_t, \ |
| pointer_guard))) |
| # endif |
| #endif |
| |
| /* How to pass the off{64}_t argument on p{readv,writev}{64}. */ |
| #undef LO_HI_LONG |
| #define LO_HI_LONG(val) (val), 0 |
| |
| #endif /* linux/x86_64/sysdep.h */ |