1 /* Copyright (C) 1992-2021 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library.  If not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #ifndef _LINUX_ALPHA_SYSDEP_H
19 #define _LINUX_ALPHA_SYSDEP_H 1
20 
21 /* There is some commonality.  */
22 #include <sysdeps/unix/sysv/linux/sysdep.h>
23 #include <sysdeps/unix/sysdep.h>
24 #include <dl-sysdep.h>         /* Defines RTLD_PRIVATE_ERRNO.  */
25 
26 #include <tls.h>
27 
28 /* For Linux we can use the system call table in the header file
29 	/usr/include/asm/unistd.h
30    of the kernel.  But these symbols do not follow the SYS_* syntax
31    so we have to redefine the `SYS_ify' macro here.  */
32 #undef SYS_ify
33 #define SYS_ify(syscall_name)	__NR_##syscall_name
34 
35 #define SINGLE_THREAD_BY_GLOBAL 1
36 
37 #ifdef __ASSEMBLER__
38 #include <asm/pal.h>
39 #include <alpha/regdef.h>
40 
41 #define __LABEL(x)	x##:
42 
43 #define LEAF(name, framesize)			\
44   .globl name;					\
45   .align 4;					\
46   .ent name, 0;					\
47   __LABEL(name)					\
48   .frame sp, framesize, ra
49 
50 #define ENTRY(name)				\
51   .globl name;					\
52   .align 4;					\
53   .ent name, 0;					\
54   __LABEL(name)					\
55   .frame sp, 0, ra
56 
57 /* Mark the end of function SYM.  */
58 #undef END
59 #define END(sym)	.end sym
60 
61 #ifdef PROF
62 # define PSEUDO_PROF				\
63 	.set noat;				\
64 	lda	AT, _mcount;			\
65 	jsr	AT, (AT), _mcount;		\
66 	.set at
67 #else
68 # define PSEUDO_PROF
69 #endif
70 
71 #ifdef PROF
72 # define PSEUDO_PROLOGUE			\
73 	.frame sp, 0, ra;			\
74 	ldgp	gp,0(pv);			\
75 	PSEUDO_PROF;				\
76 	.prologue 1
77 #elif defined PIC
78 # define PSEUDO_PROLOGUE			\
79 	.frame sp, 0, ra;			\
80 	.prologue 0
81 #else
82 # define PSEUDO_PROLOGUE			\
83 	.frame sp, 0, ra;			\
84 	ldgp	gp,0(pv);			\
85 	.prologue 1
86 #endif /* PROF */
87 
88 #ifdef PROF
89 # define USEPV_PROF	std
90 #else
91 # define USEPV_PROF	no
92 #endif
93 
94 #undef SYSCALL_ERROR_LABEL
95 #if RTLD_PRIVATE_ERRNO
96 # define SYSCALL_ERROR_LABEL	$syscall_error
97 # define SYSCALL_ERROR_HANDLER			\
98 $syscall_error:					\
99 	stl	v0, rtld_errno(gp)	!gprel;	\
100 	lda	v0, -1;				\
101 	ret
102 # define SYSCALL_ERROR_FALLTHRU
103 #elif defined(PIC)
104 # define SYSCALL_ERROR_LABEL		__syscall_error !samegp
105 # define SYSCALL_ERROR_HANDLER
106 # define SYSCALL_ERROR_FALLTHRU		br SYSCALL_ERROR_LABEL
107 #else
108 # define SYSCALL_ERROR_LABEL		$syscall_error
109 # define SYSCALL_ERROR_HANDLER			\
110 $syscall_error:					\
111 	jmp $31, __syscall_error
112 # define SYSCALL_ERROR_FALLTHRU
113 #endif /* RTLD_PRIVATE_ERRNO */
114 
115 /* Overridden by specific syscalls.  */
116 #undef PSEUDO_PREPARE_ARGS
117 #define PSEUDO_PREPARE_ARGS	/* Nothing.  */
118 
119 #define PSEUDO(name, syscall_name, args)	\
120 	.globl name;				\
121 	.align 4;				\
122 	.ent name,0;				\
123 __LABEL(name)					\
124 	PSEUDO_PROLOGUE;			\
125 	PSEUDO_PREPARE_ARGS			\
126 	lda	v0, SYS_ify(syscall_name);	\
127 	call_pal PAL_callsys;			\
128 	bne	a3, SYSCALL_ERROR_LABEL
129 
130 #undef PSEUDO_END
131 #define PSEUDO_END(sym)				\
132 	SYSCALL_ERROR_HANDLER;			\
133 	END(sym)
134 
135 #define PSEUDO_NOERRNO(name, syscall_name, args)	\
136 	.globl name;					\
137 	.align 4;					\
138 	.ent name,0;					\
139 __LABEL(name)						\
140 	PSEUDO_PROLOGUE;				\
141 	PSEUDO_PREPARE_ARGS				\
142 	lda	v0, SYS_ify(syscall_name);		\
143 	call_pal PAL_callsys;
144 
145 #undef PSEUDO_END_NOERRNO
146 #define PSEUDO_END_NOERRNO(sym)  END(sym)
147 
148 #define ret_NOERRNO ret
149 
150 #define PSEUDO_ERRVAL(name, syscall_name, args)	\
151 	.globl name;					\
152 	.align 4;					\
153 	.ent name,0;					\
154 __LABEL(name)						\
155 	PSEUDO_PROLOGUE;				\
156 	PSEUDO_PREPARE_ARGS				\
157 	lda	v0, SYS_ify(syscall_name);		\
158 	call_pal PAL_callsys;
159 
160 #undef PSEUDO_END_ERRVAL
161 #define PSEUDO_END_ERRVAL(sym)  END(sym)
162 
163 #define ret_ERRVAL ret
164 
165 #define r0	v0
166 #define r1	a4
167 
168 #define MOVE(x,y)	mov x,y
169 
170 #else /* !ASSEMBLER */
171 
172 #define INTERNAL_SYSCALL(name, nr, args...) \
173 	internal_syscall##nr(__NR_##name, args)
174 
175 #define INTERNAL_SYSCALL_NCS(name, nr, args...) \
176 	internal_syscall##nr(name, args)
177 
178 /* The normal Alpha calling convention sign-extends 32-bit quantties
179    no matter what the "real" sign of the 32-bit type.  We want to
180    preserve that when filling in values for the kernel.  */
181 #define syscall_promote(arg) \
182   (sizeof (arg) == 4 ? (long int)(int)(long int)(arg) : (long int)(arg))
183 
184 #define internal_syscall_clobbers				\
185 	"$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8",	\
186 	"$22", "$23", "$24", "$25", "$27", "$28", "memory"
187 
188 /* It is moderately important optimization-wise to limit the lifetime
189    of the hard-register variables as much as possible.  Thus we copy
190    in/out as close to the asm as possible.  */
191 
192 #define internal_syscall0(name, args...)			\
193 ({								\
194 	register long int _sc_19 __asm__("$19");		\
195 	register long int _sc_0 = name;				\
196 	__asm__ __volatile__					\
197 	  ("callsys # %0 %1 <= %2"				\
198 	   : "+v"(_sc_0), "=r"(_sc_19)				\
199 	   : : internal_syscall_clobbers,			\
200 	     "$16", "$17", "$18", "$20", "$21");		\
201 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
202 })
203 
204 #define internal_syscall1(name,arg1)				\
205 ({								\
206 	register long int _tmp_16 = syscall_promote (arg1);	\
207 	register long int _sc_0 = name;				\
208 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
209 	register long int _sc_19 __asm__("$19");		\
210 	__asm__ __volatile__					\
211 	  ("callsys # %0 %1 <= %2 %3"				\
212 	   : "+v"(_sc_0), "=r"(_sc_19), "+r"(_sc_16)		\
213 	   : : internal_syscall_clobbers,			\
214 	     "$17", "$18", "$20", "$21");			\
215 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
216 })
217 
218 #define internal_syscall2(name,arg1,arg2)			\
219 ({								\
220 	register long int _tmp_16 = syscall_promote (arg1);	\
221 	register long int _tmp_17 = syscall_promote (arg2);	\
222 	register long int _sc_0 = name;				\
223 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
224 	register long int _sc_17 __asm__("$17") = _tmp_17;	\
225 	register long int _sc_19 __asm__("$19");		\
226 	__asm__ __volatile__					\
227 	  ("callsys # %0 %1 <= %2 %3 %4"			\
228 	   : "+v"(_sc_0), "=r"(_sc_19),				\
229 	     "+r"(_sc_16), "+r"(_sc_17)				\
230 	   : : internal_syscall_clobbers,			\
231 	     "$18", "$20", "$21");				\
232 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
233 })
234 
235 #define internal_syscall3(name,arg1,arg2,arg3)			\
236 ({								\
237 	register long int _tmp_16 = syscall_promote (arg1);	\
238 	register long int _tmp_17 = syscall_promote (arg2);	\
239 	register long int _tmp_18 = syscall_promote (arg3);	\
240 	register long int _sc_0 = name;				\
241 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
242 	register long int _sc_17 __asm__("$17") = _tmp_17;	\
243 	register long int _sc_18 __asm__("$18") = _tmp_18;	\
244 	register long int _sc_19 __asm__("$19");		\
245 	__asm__ __volatile__					\
246 	  ("callsys # %0 %1 <= %2 %3 %4 %5"			\
247 	   : "+v"(_sc_0), "=r"(_sc_19), "+r"(_sc_16),		\
248 	     "+r"(_sc_17), "+r"(_sc_18)				\
249 	   : : internal_syscall_clobbers, "$20", "$21");	\
250 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
251 })
252 
253 #define internal_syscall4(name,arg1,arg2,arg3,arg4)		\
254 ({								\
255 	register long int _tmp_16 = syscall_promote (arg1);	\
256 	register long int _tmp_17 = syscall_promote (arg2);	\
257 	register long int _tmp_18 = syscall_promote (arg3);	\
258 	register long int _tmp_19 = syscall_promote (arg4);	\
259 	register long int _sc_0 = name;				\
260 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
261 	register long int _sc_17 __asm__("$17") = _tmp_17;	\
262 	register long int _sc_18 __asm__("$18") = _tmp_18;	\
263 	register long int _sc_19 __asm__("$19") = _tmp_19;	\
264 	__asm__ __volatile__					\
265 	  ("callsys # %0 %1 <= %2 %3 %4 %5 %6"			\
266 	   : "+v"(_sc_0), "+r"(_sc_19), "+r"(_sc_16),		\
267 	     "+r"(_sc_17), "+r"(_sc_18)				\
268 	   : : internal_syscall_clobbers, "$20", "$21");	\
269 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
270 })
271 
272 #define internal_syscall5(name,arg1,arg2,arg3,arg4,arg5)	\
273 ({								\
274 	register long int _tmp_16 = syscall_promote (arg1);	\
275 	register long int _tmp_17 = syscall_promote (arg2);	\
276 	register long int _tmp_18 = syscall_promote (arg3);	\
277 	register long int _tmp_19 = syscall_promote (arg4);	\
278 	register long int _tmp_20 = syscall_promote (arg5);	\
279 	register long int _sc_0 = name;				\
280 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
281 	register long int _sc_17 __asm__("$17") = _tmp_17;	\
282 	register long int _sc_18 __asm__("$18") = _tmp_18;	\
283 	register long int _sc_19 __asm__("$19") = _tmp_19;	\
284 	register long int _sc_20 __asm__("$20") = _tmp_20;	\
285 	__asm__ __volatile__					\
286 	  ("callsys # %0 %1 <= %2 %3 %4 %5 %6 %7"		\
287 	   : "+v"(_sc_0), "+r"(_sc_19), "+r"(_sc_16),		\
288 	     "+r"(_sc_17), "+r"(_sc_18), "+r"(_sc_20)		\
289 	   : : internal_syscall_clobbers, "$21");		\
290 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
291 })
292 
293 #define internal_syscall6(name,arg1,arg2,arg3,arg4,arg5,arg6)	\
294 ({								\
295 	register long int _tmp_16 = syscall_promote (arg1);	\
296 	register long int _tmp_17 = syscall_promote (arg2);	\
297 	register long int _tmp_18 = syscall_promote (arg3);	\
298 	register long int _tmp_19 = syscall_promote (arg4);	\
299 	register long int _tmp_20 = syscall_promote (arg5);	\
300 	register long int _tmp_21 = syscall_promote (arg6);	\
301 	register long int _sc_0 = name;				\
302 	register long int _sc_16 __asm__("$16") = _tmp_16;	\
303 	register long int _sc_17 __asm__("$17") = _tmp_17;	\
304 	register long int _sc_18 __asm__("$18") = _tmp_18;	\
305 	register long int _sc_19 __asm__("$19") = _tmp_19;	\
306 	register long int _sc_20 __asm__("$20") = _tmp_20;	\
307 	register long int _sc_21 __asm__("$21") = _tmp_21;	\
308 	__asm__ __volatile__					\
309 	  ("callsys # %0 %1 <= %2 %3 %4 %5 %6 %7 %8"		\
310 	   : "+v"(_sc_0), "+r"(_sc_19), "+r"(_sc_16),		\
311 	     "+r"(_sc_17), "+r"(_sc_18), "+r"(_sc_20),		\
312 	     "+r"(_sc_21)					\
313 	   : : internal_syscall_clobbers);			\
314 	_sc_19 != 0 ? -_sc_0 : _sc_0;				\
315 })
316 #endif /* ASSEMBLER */
317 
318 /* Pointer mangling support.  Note that tls access is slow enough that
319    we don't deoptimize things by placing the pointer check value there.  */
320 
321 #ifdef __ASSEMBLER__
322 # if IS_IN (rtld)
323 #  define PTR_MANGLE(dst, src, tmp)				\
324 	ldah	tmp, __pointer_chk_guard_local($29) !gprelhigh;	\
325 	ldq	tmp, __pointer_chk_guard_local(tmp) !gprellow;	\
326 	xor	src, tmp, dst
327 #  define PTR_MANGLE2(dst, src, tmp)				\
328 	xor	src, tmp, dst
329 # elif defined SHARED
330 #  define PTR_MANGLE(dst, src, tmp)		\
331 	ldq	tmp, __pointer_chk_guard;	\
332 	xor	src, tmp, dst
333 # else
334 #  define PTR_MANGLE(dst, src, tmp)		\
335 	ldq	tmp, __pointer_chk_guard_local;	\
336 	xor	src, tmp, dst
337 # endif
338 # define PTR_MANGLE2(dst, src, tmp)		\
339 	xor	src, tmp, dst
340 # define PTR_DEMANGLE(dst, tmp)   PTR_MANGLE(dst, dst, tmp)
341 # define PTR_DEMANGLE2(dst, tmp)  PTR_MANGLE2(dst, dst, tmp)
342 #else
343 # include <stdint.h>
344 # if (IS_IN (rtld) \
345       || (!defined SHARED && (IS_IN (libc) \
346 			      || IS_IN (libpthread))))
347 extern uintptr_t __pointer_chk_guard_local attribute_relro attribute_hidden;
348 #  define PTR_MANGLE(var) \
349 	(var) = (__typeof (var)) ((uintptr_t) (var) ^ __pointer_chk_guard_local)
350 # else
351 extern uintptr_t __pointer_chk_guard attribute_relro;
352 #  define PTR_MANGLE(var) \
353 	(var) = (__typeof(var)) ((uintptr_t) (var) ^ __pointer_chk_guard)
354 # endif
355 # define PTR_DEMANGLE(var)  PTR_MANGLE(var)
356 #endif /* ASSEMBLER */
357 
358 #endif /* _LINUX_ALPHA_SYSDEP_H  */
359