1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */ 2 /* 3 * s390 specific definitions for NOLIBC 4 */ 5 6 #ifndef _NOLIBC_ARCH_S390_H 7 #define _NOLIBC_ARCH_S390_H 8 #include <asm/signal.h> 9 #include <asm/unistd.h> 10 11 #include "compiler.h" 12 #include "crt.h" 13 #include "std.h" 14 15 /* Syscalls for s390: 16 * - registers are 64-bit 17 * - syscall number is passed in r1 18 * - arguments are in r2-r7 19 * - the system call is performed by calling the svc instruction 20 * - syscall return value is in r2 21 * - r1 and r2 are clobbered, others are preserved. 22 * 23 * Link s390 ABI: https://github.com/IBM/s390x-abi 24 * 25 */ 26 27 #define my_syscall0(num) \ 28 ({ \ 29 register long _num __asm__ ("1") = (num); \ 30 register long _rc __asm__ ("2"); \ 31 \ 32 __asm__ volatile ( \ 33 "svc 0\n" \ 34 : "=d"(_rc) \ 35 : "d"(_num) \ 36 : "memory", "cc" \ 37 ); \ 38 _rc; \ 39 }) 40 41 #define my_syscall1(num, arg1) \ 42 ({ \ 43 register long _num __asm__ ("1") = (num); \ 44 register long _arg1 __asm__ ("2") = (long)(arg1); \ 45 \ 46 __asm__ volatile ( \ 47 "svc 0\n" \ 48 : "+d"(_arg1) \ 49 : "d"(_num) \ 50 : "memory", "cc" \ 51 ); \ 52 _arg1; \ 53 }) 54 55 #define my_syscall2(num, arg1, arg2) \ 56 ({ \ 57 register long _num __asm__ ("1") = (num); \ 58 register long _arg1 __asm__ ("2") = (long)(arg1); \ 59 register long _arg2 __asm__ ("3") = (long)(arg2); \ 60 \ 61 __asm__ volatile ( \ 62 "svc 0\n" \ 63 : "+d"(_arg1) \ 64 : "d"(_arg2), "d"(_num) \ 65 : "memory", "cc" \ 66 ); \ 67 _arg1; \ 68 }) 69 70 #define my_syscall3(num, arg1, arg2, arg3) \ 71 ({ \ 72 register long _num __asm__ ("1") = (num); \ 73 register long _arg1 __asm__ ("2") = (long)(arg1); \ 74 register long _arg2 __asm__ ("3") = (long)(arg2); \ 75 register long _arg3 __asm__ ("4") = (long)(arg3); \ 76 \ 77 __asm__ volatile ( \ 78 "svc 0\n" \ 79 : "+d"(_arg1) \ 80 : "d"(_arg2), "d"(_arg3), "d"(_num) \ 81 : "memory", "cc" \ 82 ); \ 83 _arg1; \ 84 }) 85 86 #define my_syscall4(num, arg1, arg2, arg3, arg4) \ 87 ({ \ 88 register long _num __asm__ ("1") = (num); \ 89 register long _arg1 __asm__ ("2") = (long)(arg1); \ 90 register long _arg2 __asm__ ("3") = (long)(arg2); \ 91 register long _arg3 __asm__ ("4") = (long)(arg3); \ 92 register long _arg4 __asm__ ("5") = (long)(arg4); \ 93 \ 94 __asm__ volatile ( \ 95 "svc 0\n" \ 96 : "+d"(_arg1) \ 97 : "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_num) \ 98 : "memory", "cc" \ 99 ); \ 100 _arg1; \ 101 }) 102 103 #define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \ 104 ({ \ 105 register long _num __asm__ ("1") = (num); \ 106 register long _arg1 __asm__ ("2") = (long)(arg1); \ 107 register long _arg2 __asm__ ("3") = (long)(arg2); \ 108 register long _arg3 __asm__ ("4") = (long)(arg3); \ 109 register long _arg4 __asm__ ("5") = (long)(arg4); \ 110 register long _arg5 __asm__ ("6") = (long)(arg5); \ 111 \ 112 __asm__ volatile ( \ 113 "svc 0\n" \ 114 : "+d"(_arg1) \ 115 : "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_arg5), \ 116 "d"(_num) \ 117 : "memory", "cc" \ 118 ); \ 119 _arg1; \ 120 }) 121 122 #define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \ 123 ({ \ 124 register long _num __asm__ ("1") = (num); \ 125 register long _arg1 __asm__ ("2") = (long)(arg1); \ 126 register long _arg2 __asm__ ("3") = (long)(arg2); \ 127 register long _arg3 __asm__ ("4") = (long)(arg3); \ 128 register long _arg4 __asm__ ("5") = (long)(arg4); \ 129 register long _arg5 __asm__ ("6") = (long)(arg5); \ 130 register long _arg6 __asm__ ("7") = (long)(arg6); \ 131 \ 132 __asm__ volatile ( \ 133 "svc 0\n" \ 134 : "+d"(_arg1) \ 135 : "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_arg5), \ 136 "d"(_arg6), "d"(_num) \ 137 : "memory", "cc" \ 138 ); \ 139 _arg1; \ 140 }) 141 142 /* startup code */ 143 void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) 144 { 145 __asm__ volatile ( 146 "lgr %r2, %r15\n" /* save stack pointer to %r2, as arg1 of _start_c */ 147 "aghi %r15, -160\n" /* allocate new stackframe */ 148 "xc 0(8,%r15), 0(%r15)\n" /* clear backchain */ 149 "brasl %r14, _start_c\n" /* transfer to c runtime */ 150 ); 151 __builtin_unreachable(); 152 } 153 154 struct s390_mmap_arg_struct { 155 unsigned long addr; 156 unsigned long len; 157 unsigned long prot; 158 unsigned long flags; 159 unsigned long fd; 160 unsigned long offset; 161 }; 162 163 static __attribute__((unused)) 164 void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd, 165 off_t offset) 166 { 167 struct s390_mmap_arg_struct args = { 168 .addr = (unsigned long)addr, 169 .len = (unsigned long)length, 170 .prot = prot, 171 .flags = flags, 172 .fd = fd, 173 .offset = (unsigned long)offset 174 }; 175 176 return (void *)my_syscall1(__NR_mmap, &args); 177 } 178 #define sys_mmap sys_mmap 179 180 static __attribute__((unused)) 181 pid_t sys_fork(void) 182 { 183 return my_syscall5(__NR_clone, 0, SIGCHLD, 0, 0, 0); 184 } 185 #define sys_fork sys_fork 186 187 #endif /* _NOLIBC_ARCH_S390_H */ 188