diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h b/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h new file mode 100644 index 0000000..d52e623 --- /dev/null +++ b/sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h @@ -0,0 +1,164 @@ +/* Assembler macros for 64 bit S/390. + Copyright (C) 2001 Free Software Foundation, Inc. + Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). + 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#ifndef _LINUX_S390_SYSDEP_H +#define _LINUX_S390_SYSEDP_H + +#include <sysdeps/s390/s390-64/sysdep.h> +#include <sysdeps/unix/sysdep.h> + +/* 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. */ +/* In newer 2.1 kernels __NR_syscall is missing so we define it here. */ +#define __NR_syscall 0 + +#undef SYS_ify +#define SYS_ify(syscall_name) __NR_##syscall_name + +/* ELF-like local names start with `.L'. */ +#undef L +#define L(name) .L##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 gpr2 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. */ + +#define SYSCALL_ERROR_LABEL 0f + +#undef PSEUDO +#define PSEUDO(name, syscall_name, args) \ + .text; \ + ENTRY (name) \ + DO_CALL (args, syscall_name); \ + lghi %r4,-4095 ; \ + clgr %r2,%r4 ; \ + jnl SYSCALL_ERROR_LABEL ; \ + L(pseudo_end): + +#undef PSEUDO_END +#define PSEUDO_END(name) \ + SYSCALL_ERROR_HANDLER; \ + END (name) + +#ifndef _LIBC_REENTRANT +#ifndef PIC +#define SYSCALL_ERROR_HANDLER \ +0: lcr %r2,%r2 ; \ + larl %r1,errno ; \ + st %r2,0(%r1) ; \ + lghi %r2,-1 ; \ + br %r14 +#else +#define SYSCALL_ERROR_HANDLER \ +0: larl %r1,_GLOBAL_OFFSET_TABLE_ ; \ + lg %r1,errno@GOT(%r1) ; \ + lcr %r2,%r2 ; \ + st %r2,0(%r1) ; \ + lghi %r2,-1 ; \ + br %r14 +#endif /* PIC */ +#else +#define SYSCALL_ERROR_HANDLER \ +0: jg __syscall_error@PLT +#endif /* _LIBC_REENTRANT */ + +/* Linux takes system call arguments in registers: + + syscall number 1 call-clobbered + arg 1 2 call-clobbered + arg 2 3 call-clobbered + arg 3 4 call-clobbered + arg 4 5 call-clobbered + arg 5 6 call-saved + + (Of course a function with say 3 arguments does not have entries for + arguments 4 and 5.) + S390 does not need to do ANY stack operations to get its parameters + right. + */ + +#define DO_CALL(args, syscall) \ + svc SYS_ify (syscall) + +#define ret \ + br 14 + +#endif /* __ASSEMBLER__ */ + +#undef INLINE_SYSCALL +#define INLINE_SYSCALL(name, nr, args...) \ + ({ \ + DECLARGS_##nr(args) \ + int err; \ + asm volatile ( \ + LOADARGS_##nr \ + "svc %b1\n\t" \ + "lgr %0,%%r2\n\t" \ + : "=d" (err) \ + : "I" (__NR_##name) ASMFMT_##nr \ + : "memory", "cc", "2", "3", "4", "5", "6"); \ + if (err >= 0xfffff001) \ + { \ + __set_errno(-err); \ + err = -1; \ + } \ + (int) err; }) + +#define DECLARGS_0() +#define DECLARGS_1(arg1) \ + unsigned long gpr2 = (unsigned long) (arg1); +#define DECLARGS_2(arg1, arg2) \ + DECLARGS_1(arg1) \ + unsigned long gpr3 = (unsigned long) (arg2); +#define DECLARGS_3(arg1, arg2, arg3) \ + DECLARGS_2(arg1, arg2) \ + unsigned long gpr4 = (unsigned long) (arg3); +#define DECLARGS_4(arg1, arg2, arg3, arg4) \ + DECLARGS_3(arg1, arg2, arg3) \ + unsigned long gpr5 = (unsigned long) (arg4); +#define DECLARGS_5(arg1, arg2, arg3, arg4, arg5) \ + DECLARGS_4(arg1, arg2, arg3, arg4) \ + unsigned long gpr6 = (unsigned long) (arg5); + +#define LOADARGS_0 +#define LOADARGS_1 "LG 2,%2\n\t" +#define LOADARGS_2 LOADARGS_1 "LG 3,%3\n\t" +#define LOADARGS_3 LOADARGS_2 "LG 4,%4\n\t" +#define LOADARGS_4 LOADARGS_3 "LG 5,%5\n\t" +#define LOADARGS_5 LOADARGS_4 "LG 6,%6\n\t" + +#define ASMFMT_0 +#define ASMFMT_1 , "m" (gpr2) +#define ASMFMT_2 , "m" (gpr2), "m" (gpr3) +#define ASMFMT_3 , "m" (gpr2), "m" (gpr3), "m" (gpr4) +#define ASMFMT_4 , "m" (gpr2), "m" (gpr3), "m" (gpr4), "m" (gpr5) +#define ASMFMT_5 , "m" (gpr2), "m" (gpr3), "m" (gpr4), "m" (gpr5), "m" (gpr6) + +#endif /* _LINUX_S390_SYSDEP_H */ |