linux-zen-desktop/tools/include/nolibc/arch-s390.h

238 lines
6.2 KiB
C

/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
* s390 specific definitions for NOLIBC
*/
#ifndef _NOLIBC_ARCH_S390_H
#define _NOLIBC_ARCH_S390_H
#include <asm/signal.h>
#include <asm/unistd.h>
#include "compiler.h"
/* The struct returned by the stat() syscall, equivalent to stat64(). The
* syscall returns 116 bytes and stops in the middle of __unused.
*/
struct sys_stat_struct {
unsigned long st_dev;
unsigned long st_ino;
unsigned long st_nlink;
unsigned int st_mode;
unsigned int st_uid;
unsigned int st_gid;
unsigned int __pad1;
unsigned long st_rdev;
unsigned long st_size;
unsigned long st_atime;
unsigned long st_atime_nsec;
unsigned long st_mtime;
unsigned long st_mtime_nsec;
unsigned long st_ctime;
unsigned long st_ctime_nsec;
unsigned long st_blksize;
long st_blocks;
unsigned long __unused[3];
};
/* Syscalls for s390:
* - registers are 64-bit
* - syscall number is passed in r1
* - arguments are in r2-r7
* - the system call is performed by calling the svc instruction
* - syscall return value is in r2
* - r1 and r2 are clobbered, others are preserved.
*
* Link s390 ABI: https://github.com/IBM/s390x-abi
*
*/
#define my_syscall0(num) \
({ \
register long _num __asm__ ("1") = (num); \
register long _rc __asm__ ("2"); \
\
__asm__ volatile ( \
"svc 0\n" \
: "=d"(_rc) \
: "d"(_num) \
: "memory", "cc" \
); \
_rc; \
})
#define my_syscall1(num, arg1) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
#define my_syscall2(num, arg1, arg2) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
register long _arg2 __asm__ ("3") = (long)(arg2); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_arg2), "d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
#define my_syscall3(num, arg1, arg2, arg3) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
register long _arg2 __asm__ ("3") = (long)(arg2); \
register long _arg3 __asm__ ("4") = (long)(arg3); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_arg2), "d"(_arg3), "d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
#define my_syscall4(num, arg1, arg2, arg3, arg4) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
register long _arg2 __asm__ ("3") = (long)(arg2); \
register long _arg3 __asm__ ("4") = (long)(arg3); \
register long _arg4 __asm__ ("5") = (long)(arg4); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
register long _arg2 __asm__ ("3") = (long)(arg2); \
register long _arg3 __asm__ ("4") = (long)(arg3); \
register long _arg4 __asm__ ("5") = (long)(arg4); \
register long _arg5 __asm__ ("6") = (long)(arg5); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_arg5), \
"d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \
({ \
register long _num __asm__ ("1") = (num); \
register long _arg1 __asm__ ("2") = (long)(arg1); \
register long _arg2 __asm__ ("3") = (long)(arg2); \
register long _arg3 __asm__ ("4") = (long)(arg3); \
register long _arg4 __asm__ ("5") = (long)(arg4); \
register long _arg5 __asm__ ("6") = (long)(arg5); \
register long _arg6 __asm__ ("7") = (long)(arg6); \
\
__asm__ volatile ( \
"svc 0\n" \
: "+d"(_arg1) \
: "d"(_arg2), "d"(_arg3), "d"(_arg4), "d"(_arg5), \
"d"(_arg6), "d"(_num) \
: "memory", "cc" \
); \
_arg1; \
})
char **environ __attribute__((weak));
const unsigned long *_auxv __attribute__((weak));
/* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
{
__asm__ volatile (
"lg %r2,0(%r15)\n" /* argument count */
"la %r3,8(%r15)\n" /* argument pointers */
"xgr %r0,%r0\n" /* r0 will be our NULL value */
/* search for envp */
"lgr %r4,%r3\n" /* start at argv */
"0:\n"
"clg %r0,0(%r4)\n" /* entry zero? */
"la %r4,8(%r4)\n" /* advance pointer */
"jnz 0b\n" /* no -> test next pointer */
/* yes -> r4 now contains start of envp */
"larl %r1,environ\n"
"stg %r4,0(%r1)\n"
/* search for auxv */
"lgr %r5,%r4\n" /* start at envp */
"1:\n"
"clg %r0,0(%r5)\n" /* entry zero? */
"la %r5,8(%r5)\n" /* advance pointer */
"jnz 1b\n" /* no -> test next pointer */
"larl %r1,_auxv\n" /* yes -> store value in _auxv */
"stg %r5,0(%r1)\n"
"aghi %r15,-160\n" /* allocate new stackframe */
"xc 0(8,%r15),0(%r15)\n" /* clear backchain */
"brasl %r14,main\n" /* ret value of main is arg to exit */
"lghi %r1,1\n" /* __NR_exit */
"svc 0\n"
);
__builtin_unreachable();
}
struct s390_mmap_arg_struct {
unsigned long addr;
unsigned long len;
unsigned long prot;
unsigned long flags;
unsigned long fd;
unsigned long offset;
};
static __attribute__((unused))
void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd,
off_t offset)
{
struct s390_mmap_arg_struct args = {
.addr = (unsigned long)addr,
.len = (unsigned long)length,
.prot = prot,
.flags = flags,
.fd = fd,
.offset = (unsigned long)offset
};
return (void *)my_syscall1(__NR_mmap, &args);
}
#define sys_mmap sys_mmap
static __attribute__((unused))
pid_t sys_fork(void)
{
return my_syscall5(__NR_clone, 0, SIGCHLD, 0, 0, 0);
}
#define sys_fork sys_fork
#endif /* _NOLIBC_ARCH_S390_H */