/* Assembler macros for 64 bit S/390. Copyright (C) 2001, 2002, 2003 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 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, 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_SYSDEP_H #include #include /* 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 /* * Newer kernel versions redefined __NR_pread and __NR_pwrite to * __NR_pread64 and __NR_pwrite64. */ #ifndef __NR_pread # define __NR_pread __NR_pread64 #endif #ifndef __NR_pwrite # define __NR_pwrite __NR_pwrite64 #endif #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 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. */ #undef PSEUDO #define PSEUDO(name, syscall_name, args) \ .text; \ ENTRY (name) \ DO_CALL (syscall_name, args); \ lghi %r4,-4095 ; \ clgr %r2,%r4 ; \ jgnl 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) \ SYSCALL_ERROR_HANDLER; \ END (name) #undef PSEUDO_ERRVAL #define PSEUDO_ERRVAL(name, syscall_name, args) \ .text; \ ENTRY (name) \ DO_CALL (syscall_name, args); \ lcgr %r2,%r2 #undef PSEUDO_END_ERRVAL #define PSEUDO_END_ERRVAL(name) \ SYSCALL_ERROR_HANDLER; \ END (name) #ifndef PIC # define SYSCALL_ERROR_LABEL syscall_error # define SYSCALL_ERROR_HANDLER #else # if RTLD_PRIVATE_ERRNO # define SYSCALL_ERROR_LABEL 0f # define SYSCALL_ERROR_HANDLER \ 0: larl %r1,errno; \ lcr %r2,%r2; \ st %r2,0(%r1); \ lghi %r2,-1; \ br %r14 # elif defined _LIBC_REENTRANT # if USE___THREAD # ifndef NOT_IN_libc # define SYSCALL_ERROR_ERRNO __libc_errno # else # define SYSCALL_ERROR_ERRNO errno # endif # define SYSCALL_ERROR_LABEL 0f # define SYSCALL_ERROR_HANDLER \ 0: lcr %r0,%r2; \ larl %r1,SYSCALL_ERROR_ERRNO@indntpoff; \ lg %r1,0(%r1); \ ear %r2,%a0; \ sllg %r2,%r2,32; \ ear %r2,%a1; \ st %r0,0(%r1,%r2); \ lghi %r2,-1; \ br %r14 # else # define SYSCALL_ERROR_LABEL syscall_error@plt # define SYSCALL_ERROR_HANDLER # endif # else # define SYSCALL_ERROR_LABEL 0f # 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 /* _LIBC_REENTRANT */ #endif /* PIC */ /* 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(syscall, args) \ .if SYS_ify (syscall) < 256; \ svc SYS_ify (syscall); \ .else; \ lghi %r1,SYS_ify (syscall); \ svc 0; \ .endif #define ret \ br 14 #define ret_NOERRNO \ br 14 #define ret_ERRVAL \ br 14 #endif /* __ASSEMBLER__ */ #undef INLINE_SYSCALL #define INLINE_SYSCALL(name, nr, args...) \ ({ \ long _ret = INTERNAL_SYSCALL (name, , nr, args); \ if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_ret, ), 0)) \ { \ __set_errno (INTERNAL_SYSCALL_ERRNO (_ret, )); \ _ret = -1; \ } \ _ret; }) #undef INTERNAL_SYSCALL_DECL #define INTERNAL_SYSCALL_DECL(err) do { } while (0) #undef INTERNAL_SYSCALL_DIRECT #define INTERNAL_SYSCALL_DIRECT(name, err, nr, args...) \ ({ \ DECLARGS_##nr(args) \ register long _ret asm("2"); \ asm volatile ( \ "svc %b1\n\t" \ : "=d" (_ret) \ : "i" (__NR_##name) ASMFMT_##nr \ : "memory" ); \ _ret; }) #undef INTERNAL_SYSCALL_SVC0 #define INTERNAL_SYSCALL_SVC0(name, err, nr, args...) \ ({ \ DECLARGS_##nr(args) \ register unsigned long _nr asm("1") = (unsigned long)(__NR_##name); \ register long _ret asm("2"); \ asm volatile ( \ "svc 0\n\t" \ : "=d" (_ret) \ : "d" (_nr), "i" (__NR_##name) ASMFMT_##nr \ : "memory" ); \ _ret; }) #undef INTERNAL_SYSCALL #define INTERNAL_SYSCALL(name, err, nr, args...) \ (((__NR_##name) < 256) ? \ INTERNAL_SYSCALL_DIRECT(name, err, nr, args) : \ INTERNAL_SYSCALL_SVC0(name, err,nr, args)) #undef INTERNAL_SYSCALL_ERROR_P #define INTERNAL_SYSCALL_ERROR_P(val, err) \ ((unsigned long) (val) >= -4095UL) #undef INTERNAL_SYSCALL_ERRNO #define INTERNAL_SYSCALL_ERRNO(val, err) (-(val)) #define DECLARGS_0() #define DECLARGS_1(arg1) \ register unsigned long gpr2 asm ("2") = (unsigned long)(arg1); #define DECLARGS_2(arg1, arg2) \ DECLARGS_1(arg1) \ register unsigned long gpr3 asm ("3") = (unsigned long)(arg2); #define DECLARGS_3(arg1, arg2, arg3) \ DECLARGS_2(arg1, arg2) \ register unsigned long gpr4 asm ("4") = (unsigned long)(arg3); #define DECLARGS_4(arg1, arg2, arg3, arg4) \ DECLARGS_3(arg1, arg2, arg3) \ register unsigned long gpr5 asm ("5") = (unsigned long)(arg4); #define DECLARGS_5(arg1, arg2, arg3, arg4, arg5) \ DECLARGS_4(arg1, arg2, arg3, arg4) \ register unsigned long gpr6 asm ("6") = (unsigned long)(arg5); #define ASMFMT_0 #define ASMFMT_1 , "0" (gpr2) #define ASMFMT_2 , "0" (gpr2), "d" (gpr3) #define ASMFMT_3 , "0" (gpr2), "d" (gpr3), "d" (gpr4) #define ASMFMT_4 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5) #define ASMFMT_5 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6) #endif /* _LINUX_S390_SYSDEP_H */