Home | History | Annotate | Line # | Download | only in sys 
      1 /*	$NetBSD: syscallvar.h,v 1.12 2018/04/19 21:19:07 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software developed for The NetBSD Foundation
      8  * by Andrew Doran.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef _SYS_SYSCALLVAR_H_
     33 #define	_SYS_SYSCALLVAR_H_
     34 
     35 #ifndef _KERNEL
     36 #error nothing of interest to userspace here
     37 #endif
     38 
     39 #if defined(_KERNEL) && defined(_KERNEL_OPT)
     40 #include "opt_dtrace.h"
     41 #endif
     42 
     43 #include <sys/systm.h>
     44 #include <sys/proc.h>
     45 
     46 extern struct emul emul_netbsd;
     47 
     48 struct syscall_package {
     49 	u_short		sp_code;
     50 	u_short		sp_flags;
     51 	sy_call_t	*sp_call;
     52 };
     53 
     54 void	syscall_init(void);
     55 int	syscall_establish(const struct emul *, const struct syscall_package *);
     56 int	syscall_disestablish(const struct emul *, const struct syscall_package *);
     57 
     58 static __inline int
     59 sy_call(const struct sysent *sy, struct lwp *l, const void *uap,
     60 	register_t *rval)
     61 {
     62 	int error;
     63 
     64 	l->l_sysent = sy;
     65 	error = (*sy->sy_call)(l, uap, rval);
     66 	l->l_sysent = NULL;
     67 
     68 	return error;
     69 }
     70 
     71 static __inline int
     72 sy_invoke(const struct sysent *sy, struct lwp *l, const void *uap,
     73 	register_t *rval, int code)
     74 {
     75 	const bool do_trace = l->l_proc->p_trace_enabled &&
     76 	    (sy->sy_flags & SYCALL_INDIRECT) == 0;
     77 	int error;
     78 
     79 #ifdef KDTRACE_HOOKS
     80 #define KDTRACE_ENTRY(a)	(a)
     81 #else
     82 #define KDTRACE_ENTRY(a)	(0)
     83 #endif
     84 	if (__predict_true(!(do_trace || KDTRACE_ENTRY(sy->sy_entry)))
     85 	    || (error = trace_enter(code, sy, uap)) == 0) {
     86 		rval[0] = 0;
     87 #if !defined(__mips__) && !defined(__m68k__)
     88 		/*
     89 		 * Due to the mips userland code for SYS_break needing v1 to be
     90 		 * preserved, we can't clear this on mips.
     91 		 */
     92 		rval[1] = 0;
     93 #endif
     94 		error = sy_call(sy, l, uap, rval);
     95 	}
     96 
     97 	if (__predict_false(do_trace || KDTRACE_ENTRY(sy->sy_return))) {
     98 		trace_exit(code, sy, uap, rval, error);
     99 	}
    100 	return error;
    101 }
    102 
    103 /* inclusion in the kernel currently depends on SYSCALL_DEBUG */
    104 extern const char * const syscallnames[];
    105 extern const char * const altsyscallnames[];
    106 
    107 #endif	/* _SYS_SYSCALLVAR_H_ */
    108