xref: /netbsd-src/sys/arch/amd64/amd64/netbsd32_syscall.c (revision 68fa58437753598de948829082f591c269b48777)
1 /*	$NetBSD: netbsd32_syscall.c,v 1.34 2023/10/05 19:41:03 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
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 #if defined(_KERNEL) && defined(_KERNEL_OPT)
33 #include "opt_dtrace.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: netbsd32_syscall.c,v 1.34 2023/10/05 19:41:03 ad Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/proc.h>
42 #include <sys/signal.h>
43 /* XXX this file ought to include the netbsd32 version of these 2 headers */
44 #include <sys/syscall.h>
45 #include <sys/syscallvar.h>
46 #include <sys/syscallargs.h>
47 #include <sys/syscall_stats.h>
48 
49 #include <machine/cpu.h>
50 #include <machine/psl.h>
51 #include <machine/userret.h>
52 
53 void netbsd32_syscall_intern(struct proc *);
54 static void netbsd32_syscall(struct trapframe *);
55 
56 void
netbsd32_syscall_intern(struct proc * p)57 netbsd32_syscall_intern(struct proc *p)
58 {
59 
60 	p->p_md.md_syscall = netbsd32_syscall;
61 }
62 
63 void
netbsd32_syscall(struct trapframe * frame)64 netbsd32_syscall(struct trapframe *frame)
65 {
66 	char *params;
67 	const struct sysent *callp;
68 	struct proc *p;
69 	struct lwp *l;
70 	int error;
71 	int i;
72 	register32_t code, args[2 + SYS_MAXSYSARGS];
73 	register_t rval[2];
74 	register_t args64[SYS_MAXSYSARGS];
75 
76 	l = curlwp;
77 	p = l->l_proc;
78 
79 	code = frame->tf_rax & (SYS_NSYSENT - 1);
80 	callp = p->p_emul->e_sysent + code;
81 
82 	SYSCALL_COUNT(syscall_counts, code);
83 	SYSCALL_TIME_SYS_ENTRY(l, syscall_times, code);
84 
85 	params = (char *)frame->tf_rsp + sizeof(int);
86 
87 	if (callp->sy_argsize) {
88 		error = copyin(params, args, callp->sy_argsize);
89 		if (__predict_false(error != 0))
90 			goto bad;
91 	}
92 
93 	if (__predict_false(p->p_trace_enabled || KDTRACE_ENTRY(callp->sy_entry))
94 	    && !__predict_false(callp->sy_flags & SYCALL_INDIRECT)) {
95 		int narg = callp->sy_argsize >> 2;
96 		for (i = 0; i < narg; i++)
97 			args64[i] = args[i];
98 		error = trace_enter(code, callp, args64);
99 		if (__predict_false(error != 0))
100 			goto out;
101 	}
102 
103 	rval[0] = 0;
104 	rval[1] = 0;
105 	error = sy_call(callp, l, args, rval);
106 
107 out:
108 	if (__predict_false(p->p_trace_enabled || KDTRACE_ENTRY(callp->sy_return))
109 	    && !__predict_false(callp->sy_flags & SYCALL_INDIRECT)) {
110 		int narg = callp->sy_argsize >> 2;
111 		for (i = 0; i < narg; i++)
112 			args64[i] = args[i];
113 		trace_exit(code, callp, args64, rval, error);
114 	}
115 
116 	if (__predict_true(error == 0)) {
117 		frame->tf_rax = rval[0];
118 		frame->tf_rdx = rval[1];
119 		frame->tf_rflags &= ~PSL_C;	/* carry bit */
120 	} else {
121 		switch (error) {
122 		case ERESTART:
123 			/*
124 			 * The offset to adjust the PC by depends on whether we
125 			 * entered the kernel through the trap or call gate.
126 			 * We saved the instruction size in tf_err on entry.
127 			 */
128 			frame->tf_rip -= frame->tf_err;
129 			break;
130 		case EJUSTRETURN:
131 			/* nothing to do */
132 			break;
133 		default:
134 		bad:
135 			frame->tf_rax = error;
136 			frame->tf_rflags |= PSL_C;	/* carry bit */
137 			break;
138 		}
139 	}
140 
141 	SYSCALL_TIME_SYS_EXIT(l);
142 	userret(l);
143 }
144