225 строки
11 KiB
C
225 строки
11 KiB
C
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
|
|
/*
|
|
* MIPS specific definitions for NOLIBC
|
|
* Copyright (C) 2017-2022 Willy Tarreau <w@1wt.eu>
|
|
*/
|
|
|
|
#ifndef _NOLIBC_ARCH_MIPS_H
|
|
#define _NOLIBC_ARCH_MIPS_H
|
|
|
|
/* The struct returned by the stat() syscall. 88 bytes are returned by the
|
|
* syscall.
|
|
*/
|
|
struct sys_stat_struct {
|
|
unsigned int st_dev;
|
|
long st_pad1[3];
|
|
unsigned long st_ino;
|
|
unsigned int st_mode;
|
|
unsigned int st_nlink;
|
|
unsigned int st_uid;
|
|
unsigned int st_gid;
|
|
unsigned int st_rdev;
|
|
long st_pad2[2];
|
|
long st_size;
|
|
long st_pad3;
|
|
|
|
long st_atime;
|
|
long st_atime_nsec;
|
|
long st_mtime;
|
|
long st_mtime_nsec;
|
|
|
|
long st_ctime;
|
|
long st_ctime_nsec;
|
|
long st_blksize;
|
|
long st_blocks;
|
|
long st_pad4[14];
|
|
};
|
|
|
|
/* Syscalls for MIPS ABI O32 :
|
|
* - WARNING! there's always a delayed slot!
|
|
* - WARNING again, the syntax is different, registers take a '$' and numbers
|
|
* do not.
|
|
* - registers are 32-bit
|
|
* - stack is 8-byte aligned
|
|
* - syscall number is passed in v0 (starts at 0xfa0).
|
|
* - arguments are in a0, a1, a2, a3, then the stack. The caller needs to
|
|
* leave some room in the stack for the callee to save a0..a3 if needed.
|
|
* - Many registers are clobbered, in fact only a0..a2 and s0..s8 are
|
|
* preserved. See: https://www.linux-mips.org/wiki/Syscall as well as
|
|
* scall32-o32.S in the kernel sources.
|
|
* - the system call is performed by calling "syscall"
|
|
* - syscall return comes in v0, and register a3 needs to be checked to know
|
|
* if an error occurred, in which case errno is in v0.
|
|
* - the arguments are cast to long and assigned into the target registers
|
|
* which are then simply passed as registers to the asm code, so that we
|
|
* don't have to experience issues with register constraints.
|
|
*/
|
|
|
|
#define my_syscall0(num) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg4 __asm__ ("a3"); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"syscall\n" \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r"(_num), "=r"(_arg4) \
|
|
: "r"(_num) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
#define my_syscall1(num, arg1) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg1 __asm__ ("a0") = (long)(arg1); \
|
|
register long _arg4 __asm__ ("a3"); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"syscall\n" \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r"(_num), "=r"(_arg4) \
|
|
: "0"(_num), \
|
|
"r"(_arg1) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
#define my_syscall2(num, arg1, arg2) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg1 __asm__ ("a0") = (long)(arg1); \
|
|
register long _arg2 __asm__ ("a1") = (long)(arg2); \
|
|
register long _arg4 __asm__ ("a3"); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"syscall\n" \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r"(_num), "=r"(_arg4) \
|
|
: "0"(_num), \
|
|
"r"(_arg1), "r"(_arg2) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
#define my_syscall3(num, arg1, arg2, arg3) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg1 __asm__ ("a0") = (long)(arg1); \
|
|
register long _arg2 __asm__ ("a1") = (long)(arg2); \
|
|
register long _arg3 __asm__ ("a2") = (long)(arg3); \
|
|
register long _arg4 __asm__ ("a3"); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"syscall\n" \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r"(_num), "=r"(_arg4) \
|
|
: "0"(_num), \
|
|
"r"(_arg1), "r"(_arg2), "r"(_arg3) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
#define my_syscall4(num, arg1, arg2, arg3, arg4) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg1 __asm__ ("a0") = (long)(arg1); \
|
|
register long _arg2 __asm__ ("a1") = (long)(arg2); \
|
|
register long _arg3 __asm__ ("a2") = (long)(arg3); \
|
|
register long _arg4 __asm__ ("a3") = (long)(arg4); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"syscall\n" \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r" (_num), "=r"(_arg4) \
|
|
: "0"(_num), \
|
|
"r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
|
|
({ \
|
|
register long _num __asm__ ("v0") = (num); \
|
|
register long _arg1 __asm__ ("a0") = (long)(arg1); \
|
|
register long _arg2 __asm__ ("a1") = (long)(arg2); \
|
|
register long _arg3 __asm__ ("a2") = (long)(arg3); \
|
|
register long _arg4 __asm__ ("a3") = (long)(arg4); \
|
|
register long _arg5 = (long)(arg5); \
|
|
\
|
|
__asm__ volatile ( \
|
|
"addiu $sp, $sp, -32\n" \
|
|
"sw %7, 16($sp)\n" \
|
|
"syscall\n " \
|
|
"addiu $sp, $sp, 32\n" \
|
|
: "=r" (_num), "=r"(_arg4) \
|
|
: "0"(_num), \
|
|
"r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5) \
|
|
: "memory", "cc", "at", "v1", "hi", "lo", \
|
|
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8", "t9" \
|
|
); \
|
|
_arg4 ? -_num : _num; \
|
|
})
|
|
|
|
char **environ __attribute__((weak));
|
|
const unsigned long *_auxv __attribute__((weak));
|
|
|
|
/* startup code, note that it's called __start on MIPS */
|
|
void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void)
|
|
{
|
|
__asm__ volatile (
|
|
//".set nomips16\n"
|
|
".set push\n"
|
|
".set noreorder\n"
|
|
".option pic0\n"
|
|
//".ent __start\n"
|
|
//"__start:\n"
|
|
"lw $a0,($sp)\n" // argc was in the stack
|
|
"addiu $a1, $sp, 4\n" // argv = sp + 4
|
|
"sll $a2, $a0, 2\n" // a2 = argc * 4
|
|
"add $a2, $a2, $a1\n" // envp = argv + 4*argc ...
|
|
"addiu $a2, $a2, 4\n" // ... + 4
|
|
"lui $a3, %hi(environ)\n" // load environ into a3 (hi)
|
|
"addiu $a3, %lo(environ)\n" // load environ into a3 (lo)
|
|
"sw $a2,($a3)\n" // store envp(a2) into environ
|
|
|
|
"move $t0, $a2\n" // iterate t0 over envp, look for NULL
|
|
"0:" // do {
|
|
"lw $a3, ($t0)\n" // a3=*(t0);
|
|
"bne $a3, $0, 0b\n" // } while (a3);
|
|
"addiu $t0, $t0, 4\n" // delayed slot: t0+=4;
|
|
"lui $a3, %hi(_auxv)\n" // load _auxv into a3 (hi)
|
|
"addiu $a3, %lo(_auxv)\n" // load _auxv into a3 (lo)
|
|
"sw $t0, ($a3)\n" // store t0 into _auxv
|
|
|
|
"li $t0, -8\n"
|
|
"and $sp, $sp, $t0\n" // sp must be 8-byte aligned
|
|
"addiu $sp,$sp,-16\n" // the callee expects to save a0..a3 there!
|
|
"jal main\n" // main() returns the status code, we'll exit with it.
|
|
"nop\n" // delayed slot
|
|
"move $a0, $v0\n" // retrieve 32-bit exit code from v0
|
|
"li $v0, 4001\n" // NR_exit == 4001
|
|
"syscall\n"
|
|
//".end __start\n"
|
|
".set pop\n"
|
|
);
|
|
__builtin_unreachable();
|
|
}
|
|
|
|
#endif // _NOLIBC_ARCH_MIPS_H
|