1 /* Syscall definitions, Linux PowerPC generic version.
2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <http://www.gnu.org/licenses/>.  */
18 
19 #ifndef _LINUX_POWERPC_SYSDEP_H
20 #define _LINUX_POWERPC_SYSDEP_H 1
21 
22 #include <sysdeps/unix/sysv/linux/sysdep.h>
23 #include <sysdeps/unix/powerpc/sysdep.h>
24 #include <tls.h>
25 /* Define __set_errno() for INLINE_SYSCALL macro below.  */
26 #include <errno.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 a macro which expands inline into the wrapper code for a system
36    call. This use is for internal calls that do not need to handle errors
37    normally. It will never touch errno. This returns just what the kernel
38    gave back in the non-error (CR0.SO cleared) case, otherwise (CR0.SO set)
39    the negation of the return value in the kernel gets reverted.  */
40 
41 #define INTERNAL_VSYSCALL_CALL_TYPE(funcptr, type, nr, args...)         \
42   ({									\
43     register void *r0  __asm__ ("r0");					\
44     register long int r3  __asm__ ("r3");				\
45     register long int r4  __asm__ ("r4");				\
46     register long int r5  __asm__ ("r5");				\
47     register long int r6  __asm__ ("r6");				\
48     register long int r7  __asm__ ("r7");				\
49     register long int r8  __asm__ ("r8");				\
50     register type rval  __asm__ ("r3");				        \
51     LOADARGS_##nr (funcptr, args);					\
52     __asm__ __volatile__						\
53       ("mtctr %0\n\t"							\
54        "bctrl\n\t"							\
55        "mfcr  %0\n\t"							\
56        "0:"								\
57        : "+r" (r0), "+r" (r3), "+r" (r4), "+r" (r5),  "+r" (r6),        \
58          "+r" (r7), "+r" (r8)						\
59        : : "r9", "r10", "r11", "r12",					\
60            "cr0", "cr1", "cr5", "cr6", "cr7",				\
61            "xer", "lr", "ctr", "memory");				\
62     __asm__ __volatile__ ("" : "=r" (rval) : "r" (r3));		        \
63     (long int) r0 & (1 << 28) ? -rval : rval;				\
64   })
65 
66 #define INTERNAL_VSYSCALL_CALL(funcptr, nr, args...)			\
67   INTERNAL_VSYSCALL_CALL_TYPE(funcptr, long int, nr, args)
68 
69 #define DECLARE_REGS				\
70   register long int r0  __asm__ ("r0");		\
71   register long int r3  __asm__ ("r3");		\
72   register long int r4  __asm__ ("r4");		\
73   register long int r5  __asm__ ("r5");		\
74   register long int r6  __asm__ ("r6");		\
75   register long int r7  __asm__ ("r7");		\
76   register long int r8  __asm__ ("r8");
77 
78 #define SYSCALL_SCV(nr)				\
79   ({						\
80     __asm__ __volatile__			\
81       (".machine \"push\"\n\t"			\
82        ".machine \"power9\"\n\t"		\
83        "scv 0\n\t"				\
84        ".machine \"pop\"\n\t"			\
85        "0:"					\
86        : "=&r" (r0),				\
87 	 "=&r" (r3), "=&r" (r4), "=&r" (r5),	\
88 	 "=&r" (r6), "=&r" (r7), "=&r" (r8)	\
89        : ASM_INPUT_##nr			\
90        : "r9", "r10", "r11", "r12",		\
91 	 "cr0", "cr1", "cr5", "cr6", "cr7",	\
92 	 "xer", "lr", "ctr", "memory"); 	\
93     r3;					\
94   })
95 
96 #define SYSCALL_SC(nr)				\
97   ({						\
98     __asm__ __volatile__			\
99       ("sc\n\t"				\
100        "mfcr %0\n\t"				\
101        "0:"					\
102        : "=&r" (r0),				\
103 	 "=&r" (r3), "=&r" (r4), "=&r" (r5),	\
104 	 "=&r" (r6), "=&r" (r7), "=&r" (r8)	\
105        : ASM_INPUT_##nr			\
106        : "r9", "r10", "r11", "r12",		\
107 	 "xer", "cr0", "ctr", "memory");	\
108     r0 & (1 << 28) ? -r3 : r3;			\
109   })
110 
111 /* This will only be non-empty for 64-bit systems, see below.  */
112 #define TRY_SYSCALL_SCV(nr)
113 
114 #if defined(__PPC64__) || defined(__powerpc64__)
115 # define SYSCALL_ARG_SIZE 8
116 
117 /* For the static case, unlike the dynamic loader, there is no compile-time way
118    to check if we are inside startup code.  So we need to check if the thread
119    pointer has already been setup before trying to access the TLS.  */
120 # ifndef SHARED
121 #  define CHECK_THREAD_POINTER (__thread_register != 0)
122 # else
123 #  define CHECK_THREAD_POINTER (1)
124 # endif
125 
126 /* When inside the dynamic loader, the thread pointer may not have been
127    initialized yet, so don't check for scv support in that case.  */
128 # if defined(USE_PPC_SCV) && !IS_IN(rtld)
129 #  undef TRY_SYSCALL_SCV
130 #  define TRY_SYSCALL_SCV(nr)						\
131   CHECK_THREAD_POINTER && THREAD_GET_HWCAP() & PPC_FEATURE2_SCV ?	\
132       SYSCALL_SCV(nr) :
133 # endif
134 
135 #else
136 # define SYSCALL_ARG_SIZE 4
137 #endif
138 
139 # define INTERNAL_SYSCALL_NCS(name, nr, args...)	\
140   ({							\
141     DECLARE_REGS;					\
142     LOADARGS_##nr (name, ##args);			\
143     TRY_SYSCALL_SCV(nr)					\
144     SYSCALL_SC(nr);					\
145   })
146 
147 #undef INTERNAL_SYSCALL
148 #define INTERNAL_SYSCALL(name, nr, args...)				\
149   INTERNAL_SYSCALL_NCS (__NR_##name, nr, args)
150 
151 #define LOADARGS_0(name, dummy) \
152 	r0 = name
153 #define LOADARGS_1(name, __arg1) \
154 	long int _arg1 = (long int) (__arg1); \
155 	LOADARGS_0(name, 0); \
156 	extern void __illegally_sized_syscall_arg1 (void); \
157 	if (__builtin_classify_type (__arg1) != 5 \
158 	    && sizeof (__arg1) > SYSCALL_ARG_SIZE) \
159 	  __illegally_sized_syscall_arg1 (); \
160 	r3 = _arg1
161 #define LOADARGS_2(name, __arg1, __arg2) \
162 	long int _arg2 = (long int) (__arg2); \
163 	LOADARGS_1(name, __arg1); \
164 	extern void __illegally_sized_syscall_arg2 (void); \
165 	if (__builtin_classify_type (__arg2) != 5 \
166 	    && sizeof (__arg2) > SYSCALL_ARG_SIZE) \
167 	  __illegally_sized_syscall_arg2 (); \
168 	r4 = _arg2
169 #define LOADARGS_3(name, __arg1, __arg2, __arg3) \
170 	long int _arg3 = (long int) (__arg3); \
171 	LOADARGS_2(name, __arg1, __arg2); \
172 	extern void __illegally_sized_syscall_arg3 (void); \
173 	if (__builtin_classify_type (__arg3) != 5 \
174 	    && sizeof (__arg3) > SYSCALL_ARG_SIZE) \
175 	  __illegally_sized_syscall_arg3 (); \
176 	r5 = _arg3
177 #define LOADARGS_4(name, __arg1, __arg2, __arg3, __arg4) \
178 	long int _arg4 = (long int) (__arg4); \
179 	LOADARGS_3(name, __arg1, __arg2, __arg3); \
180 	extern void __illegally_sized_syscall_arg4 (void); \
181 	if (__builtin_classify_type (__arg4) != 5 \
182 	    && sizeof (__arg4) > SYSCALL_ARG_SIZE) \
183 	  __illegally_sized_syscall_arg4 (); \
184 	r6 = _arg4
185 #define LOADARGS_5(name, __arg1, __arg2, __arg3, __arg4, __arg5) \
186 	long int _arg5 = (long int) (__arg5); \
187 	LOADARGS_4(name, __arg1, __arg2, __arg3, __arg4); \
188 	extern void __illegally_sized_syscall_arg5 (void); \
189 	if (__builtin_classify_type (__arg5) != 5 \
190 	    && sizeof (__arg5) > SYSCALL_ARG_SIZE) \
191 	  __illegally_sized_syscall_arg5 (); \
192 	r7 = _arg5
193 #define LOADARGS_6(name, __arg1, __arg2, __arg3, __arg4, __arg5, __arg6) \
194 	long int _arg6 = (long int) (__arg6); \
195 	LOADARGS_5(name, __arg1, __arg2, __arg3, __arg4, __arg5); \
196 	extern void __illegally_sized_syscall_arg6 (void); \
197 	if (__builtin_classify_type (__arg6) != 5 \
198 	    && sizeof (__arg6) > SYSCALL_ARG_SIZE) \
199 	  __illegally_sized_syscall_arg6 (); \
200 	r8 = _arg6
201 
202 #define ASM_INPUT_0 "0" (r0)
203 #define ASM_INPUT_1 ASM_INPUT_0, "1" (r3)
204 #define ASM_INPUT_2 ASM_INPUT_1, "2" (r4)
205 #define ASM_INPUT_3 ASM_INPUT_2, "3" (r5)
206 #define ASM_INPUT_4 ASM_INPUT_3, "4" (r6)
207 #define ASM_INPUT_5 ASM_INPUT_4, "5" (r7)
208 #define ASM_INPUT_6 ASM_INPUT_5, "6" (r8)
209 
210 
211 /* Pointer mangling support.  */
212 #if IS_IN (rtld)
213 /* We cannot use the thread descriptor because in ld.so we use setjmp
214    earlier than the descriptor is initialized.  */
215 #else
216 # ifdef __ASSEMBLER__
217 #  if defined(__PPC64__) || defined(__powerpc64__)
218 #   define LOAD  ld
219 #   define TPREG r13
220 #  else
221 #   define LOAD  lwz
222 #   define TPREG r2
223 #  endif
224 #  define PTR_MANGLE(reg, tmpreg) \
225 	LOAD	tmpreg,POINTER_GUARD(TPREG); \
226 	xor	reg,tmpreg,reg
227 #  define PTR_MANGLE2(reg, tmpreg) \
228 	xor	reg,tmpreg,reg
229 #  define PTR_MANGLE3(destreg, reg, tmpreg) \
230 	LOAD	tmpreg,POINTER_GUARD(TPREG); \
231 	xor	destreg,tmpreg,reg
232 #  define PTR_DEMANGLE(reg, tmpreg) PTR_MANGLE (reg, tmpreg)
233 #  define PTR_DEMANGLE2(reg, tmpreg) PTR_MANGLE2 (reg, tmpreg)
234 #  define PTR_DEMANGLE3(destreg, reg, tmpreg) PTR_MANGLE3 (destreg, reg, tmpreg)
235 # else
236 #  define PTR_MANGLE(var) \
237   (var) = (__typeof (var)) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
238 #  define PTR_DEMANGLE(var)	PTR_MANGLE (var)
239 # endif
240 #endif
241 
242 /* List of system calls which are supported as vsyscalls.  */
243 #define VDSO_NAME  "LINUX_2.6.15"
244 #define VDSO_HASH  123718565
245 
246 #if defined(__PPC64__) || defined(__powerpc64__)
247 #define HAVE_CLOCK_GETRES64_VSYSCALL	"__kernel_clock_getres"
248 #define HAVE_CLOCK_GETTIME64_VSYSCALL	"__kernel_clock_gettime"
249 #else
250 #define HAVE_CLOCK_GETRES_VSYSCALL	"__kernel_clock_getres"
251 #define HAVE_CLOCK_GETTIME_VSYSCALL	"__kernel_clock_gettime"
252 #endif
253 #define HAVE_GETCPU_VSYSCALL		"__kernel_getcpu"
254 #define HAVE_TIME_VSYSCALL		"__kernel_time"
255 #define HAVE_GETTIMEOFDAY_VSYSCALL      "__kernel_gettimeofday"
256 #define HAVE_GET_TBFREQ                 "__kernel_get_tbfreq"
257 
258 #endif /* _LINUX_POWERPC_SYSDEP_H  */
259