1 /* Assembler macros for 64 bit S/390.
2 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
3 Free Software Foundation, Inc.
4 Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
5 This file is part of the GNU C Library.
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version.
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, write to the Free
19 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22 #ifndef _LINUX_S390_SYSDEP_H
23 #define _LINUX_S390_SYSDEP_H
25 #include <sysdeps/s390/s390-64/sysdep.h>
26 #include <sysdeps/unix/sysdep.h>
27 #include <dl-sysdep.h> /* For RTLD_PRIVATE_ERRNO. */
30 /* For Linux we can use the system call table in the header file
31 /usr/include/asm/unistd.h
32 of the kernel. But these symbols do not follow the SYS_* syntax
33 so we have to redefine the `SYS_ify' macro here. */
34 /* In newer 2.1 kernels __NR_syscall is missing so we define it here. */
35 #define __NR_syscall 0
38 * Newer kernel versions redefined __NR_pread and __NR_pwrite to
39 * __NR_pread64 and __NR_pwrite64.
42 # define __NR_pread __NR_pread64
45 # define __NR_pwrite __NR_pwrite64
49 #define SYS_ify(syscall_name) __NR_##syscall_name
53 /* Linux uses a negative return value to indicate syscall errors, unlike
54 most Unices, which use the condition codes' carry flag.
56 Since version 2.1 the return value of a system call might be negative
57 even if the call succeeded. E.g., the `lseek' system call might return
58 a large offset. Therefore we must not anymore test for < 0, but test
59 for a real error by making sure the value in gpr2 is a real error
60 number. Linus said he will make sure the no syscall returns a value
61 in -1 .. -4095 as a valid result so we can savely test with -4095. */
64 #define PSEUDO(name, syscall_name, args) \
67 DO_CALL (syscall_name, args); \
70 jgnl SYSCALL_ERROR_LABEL
73 #define PSEUDO_END(name) \
74 SYSCALL_ERROR_HANDLER; \
78 #define PSEUDO_NOERRNO(name, syscall_name, args) \
81 DO_CALL (syscall_name, args)
83 #undef PSEUDO_END_NOERRNO
84 #define PSEUDO_END_NOERRNO(name) \
85 SYSCALL_ERROR_HANDLER; \
89 #define PSEUDO_ERRVAL(name, syscall_name, args) \
92 DO_CALL (syscall_name, args); \
95 #undef PSEUDO_END_ERRVAL
96 #define PSEUDO_END_ERRVAL(name) \
97 SYSCALL_ERROR_HANDLER; \
101 # define SYSCALL_ERROR_LABEL syscall_error
102 # define SYSCALL_ERROR_HANDLER
104 # if RTLD_PRIVATE_ERRNO
105 # define SYSCALL_ERROR_LABEL 0f
106 # define SYSCALL_ERROR_HANDLER \
107 0: larl %r1,rtld_errno; \
112 # elif defined _LIBC_REENTRANT
115 # define SYSCALL_ERROR_ERRNO __libc_errno
117 # define SYSCALL_ERROR_ERRNO errno
119 # define SYSCALL_ERROR_LABEL 0f
120 # define SYSCALL_ERROR_HANDLER \
122 larl %r1,SYSCALL_ERROR_ERRNO@indntpoff; \
131 # define SYSCALL_ERROR_LABEL syscall_error@plt
132 # define SYSCALL_ERROR_HANDLER
135 # define SYSCALL_ERROR_LABEL 0f
136 # define SYSCALL_ERROR_HANDLER \
137 0: larl %r1,_GLOBAL_OFFSET_TABLE_; \
138 lg %r1,errno@GOT(%r1); \
143 # endif /* _LIBC_REENTRANT */
146 /* Linux takes system call arguments in registers:
148 syscall number 1 call-clobbered
149 arg 1 2 call-clobbered
150 arg 2 3 call-clobbered
151 arg 3 4 call-clobbered
152 arg 4 5 call-clobbered
156 (Of course a function with say 3 arguments does not have entries for
158 For system calls with 6 parameters a stack operation is required
159 to load the 6th parameter to register 7. Call saved register 7 is
160 moved to register 0 and back to avoid an additional stack frame.
163 #define DO_CALL(syscall, args) \
168 .if SYS_ify (syscall) < 256; \
169 svc SYS_ify (syscall); \
171 lghi %r1,SYS_ify (syscall); \
181 #define ret_NOERRNO \
187 #endif /* __ASSEMBLER__ */
189 #undef INLINE_SYSCALL
190 #define INLINE_SYSCALL(name, nr, args...) \
192 long _ret = INTERNAL_SYSCALL (name, , nr, args); \
193 if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_ret, ), 0)) \
195 __set_errno (INTERNAL_SYSCALL_ERRNO (_ret, )); \
200 #undef INTERNAL_SYSCALL_DECL
201 #define INTERNAL_SYSCALL_DECL(err) do { } while (0)
203 #undef INTERNAL_SYSCALL_DIRECT
204 #define INTERNAL_SYSCALL_DIRECT(name, err, nr, args...) \
206 DECLARGS_##nr(args) \
207 register long _ret asm("2"); \
211 : "i" (__NR_##name) ASMFMT_##nr \
215 #undef INTERNAL_SYSCALL_SVC0
216 #define INTERNAL_SYSCALL_SVC0(name, err, nr, args...) \
218 DECLARGS_##nr(args) \
219 register unsigned long _nr asm("1") = (unsigned long)(__NR_##name); \
220 register long _ret asm("2"); \
224 : "d" (_nr) ASMFMT_##nr \
228 #undef INTERNAL_SYSCALL_NCS
229 #define INTERNAL_SYSCALL_NCS(no, err, nr, args...) \
231 DECLARGS_##nr(args) \
232 register unsigned long _nr asm("1") = (unsigned long)(no); \
233 register long _ret asm("2"); \
237 : "d" (_nr) ASMFMT_##nr \
241 #undef INTERNAL_SYSCALL
242 #define INTERNAL_SYSCALL(name, err, nr, args...) \
243 (((__NR_##name) < 256) ? \
244 INTERNAL_SYSCALL_DIRECT(name, err, nr, args) : \
245 INTERNAL_SYSCALL_SVC0(name, err,nr, args))
247 #undef INTERNAL_SYSCALL_ERROR_P
248 #define INTERNAL_SYSCALL_ERROR_P(val, err) \
249 ((unsigned long) (val) >= -4095UL)
251 #undef INTERNAL_SYSCALL_ERRNO
252 #define INTERNAL_SYSCALL_ERRNO(val, err) (-(val))
255 #define DECLARGS_1(arg1) \
256 register unsigned long gpr2 asm ("2") = (unsigned long)(arg1);
257 #define DECLARGS_2(arg1, arg2) \
259 register unsigned long gpr3 asm ("3") = (unsigned long)(arg2);
260 #define DECLARGS_3(arg1, arg2, arg3) \
261 DECLARGS_2(arg1, arg2) \
262 register unsigned long gpr4 asm ("4") = (unsigned long)(arg3);
263 #define DECLARGS_4(arg1, arg2, arg3, arg4) \
264 DECLARGS_3(arg1, arg2, arg3) \
265 register unsigned long gpr5 asm ("5") = (unsigned long)(arg4);
266 #define DECLARGS_5(arg1, arg2, arg3, arg4, arg5) \
267 DECLARGS_4(arg1, arg2, arg3, arg4) \
268 register unsigned long gpr6 asm ("6") = (unsigned long)(arg5);
269 #define DECLARGS_6(arg1, arg2, arg3, arg4, arg5, arg6) \
270 DECLARGS_5(arg1, arg2, arg3, arg4, arg5) \
271 register unsigned long gpr7 asm ("7") = (unsigned long)(arg6);
274 #define ASMFMT_1 , "0" (gpr2)
275 #define ASMFMT_2 , "0" (gpr2), "d" (gpr3)
276 #define ASMFMT_3 , "0" (gpr2), "d" (gpr3), "d" (gpr4)
277 #define ASMFMT_4 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5)
278 #define ASMFMT_5 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6)
279 #define ASMFMT_6 , "0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5), "d" (gpr6), "d" (gpr7)
281 /* Pointer mangling support. */
282 #if defined NOT_IN_libc && defined IS_IN_rtld
283 /* We cannot use the thread descriptor because in ld.so we use setjmp
284 earlier than the descriptor is initialized. */
286 /* For the time being just use stack_guard rather than a separate
288 # ifdef __ASSEMBLER__
289 # define PTR_MANGLE(reg, tmpreg) \
291 sllg tmpreg,tmpreg,32; \
293 xg reg,STACK_GUARD(tmpreg)
294 # define PTR_MANGLE2(reg, tmpreg) \
295 xg reg,STACK_GUARD(tmpreg)
296 # define PTR_DEMANGLE(reg, tmpreg) PTR_MANGLE (reg, tmpreg)
298 # define PTR_MANGLE(var) \
299 (var) = (void *) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
300 # define PTR_DEMANGLE(var) PTR_MANGLE (var)
304 #endif /* _LINUX_S390_SYSDEP_H */