xref: /openbsd-src/lib/libc/arch/mips64/SYS.h (revision 5bcead818ba71dc1c4fad02a24986a5b47ae1c58)

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ralph Campbell.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      $OpenBSD: SYS.h,v 1.14 2023/12/11 22:24:16 kettenis Exp $
 */

#include <sys/syscall.h>
#include <machine/asm.h>

/*
 * We define a hidden alias with the prefix "_libc_" for each global symbol
 * that may be used internally.  By referencing _libc_x instead of x, other
 * parts of libc prevent overriding by the application and avoid unnecessary
 * relocations.
 */
#define _HIDDEN(x)		_libc_##x
#define _HIDDEN_ALIAS(x,y)			\
	STRONG_ALIAS(_HIDDEN(x),y);		\
	.hidden _HIDDEN(x)
#define _HIDDEN_FALIAS(x,y)			\
	_HIDDEN_ALIAS(x,y);			\
	.type _HIDDEN(x),@function

/*
 * For functions implemented in ASM that aren't syscalls.
 *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
 *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
 */
#define	END_STRONG(x)	END(x);					\
			_HIDDEN_FALIAS(x,x);			\
			.size _HIDDEN(x), . - _HIDDEN(x)
#define	END_WEAK(x)	END_STRONG(x); .weak x

#define CERROR		__cerror
	.hidden	CERROR

# define __ENTRY(p,x)		ENTRY(p ## x)

# define __DO_SYSCALL(x)					\
				li	v0,SYS_ ## x;		\
			97:	syscall;			\
				PINSYSCALL(SYS_ ## x, 97b)	\


# define __LEAF2(p,x,sz)	LEAF(p ## x, sz) \
				WEAK_ALIAS(x, p ## x);

# define __END2_HIDDEN(p,x)	END(p ## x); 		\
				_HIDDEN_FALIAS(x, p ## x); \
				.size _HIDDEN(x), . - _HIDDEN(x)
# define __END2(p,x)		__END2_HIDDEN(p,x);	\
				.size x, . - x

#define __PSEUDO_NOERROR(p,x,y)				\
		__LEAF2(p,x, 0);			\
			__DO_SYSCALL(y);		\
			j	ra;			\
		__END2(p,x)

#define __PSEUDO(p,x,y)   				\
		__LEAF2(p,x,32);			\
			PTR_SUBU sp,32;			\
			SETUP_GP64(16,_HIDDEN(x));	\
			__DO_SYSCALL(y);		\
			bne	a3,zero,1f;		\
			RESTORE_GP64;			\
			PTR_ADDU sp,32;			\
			j	ra;			\
		1:	LA	t9,CERROR;		\
			RESTORE_GP64;			\
			PTR_ADDU sp,32;			\
			jr	t9;			\
		__END2(p,x)
#define __PSEUDO_HIDDEN(p,x,y)   			\
		LEAF(p ## x,32);			\
			PTR_SUBU sp,32;			\
			SETUP_GP64(16,_HIDDEN(x));	\
			__DO_SYSCALL(y);		\
			bne	a3,zero,1f;		\
			RESTORE_GP64;			\
			PTR_ADDU sp,32;			\
			j	ra;			\
		1:	LA	t9,CERROR;		\
			RESTORE_GP64;			\
			PTR_ADDU sp,32;			\
			jr	t9;			\
		__END2_HIDDEN(p,x)


#define RSYSCALL(x)		__PSEUDO(_thread_sys_,x,x)
#define RSYSCALL_HIDDEN(x)	__PSEUDO_HIDDEN(_thread_sys_,x,x)
#define PSEUDO(x,y)		__PSEUDO(_thread_sys_,x,y)
#define PSEUDO_NOERROR(x,y)	__PSEUDO_NOERROR(_thread_sys_,x,y)

#define	SYSLEAF(x, sz)		__LEAF2(_thread_sys_,x, sz)
#define	SYSLEAF_HIDDEN(x, sz)	LEAF(_thread_sys_ ## x, sz)
#define	SYSCALL_END(x)		__END2(_thread_sys_,x)
#define	SYSCALL_END_HIDDEN(x)	__END2_HIDDEN(_thread_sys_,x)

#define PINSYSCALL(sysno, label)					\
	.pushsection .openbsd.syscalls,"",@progbits;			\
	.p2align 2;							\
	.long label;							\
	.long sysno;							\
	.popsection;