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-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h164
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 0000000000..d52e623999
--- /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 */