xref: /freebsd/sys/amd64/ia32/ia32_syscall.c (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
1 /*-
2  * Copyright (C) 1994, David Greenman
3  * Copyright (c) 1990, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the University of Utah, and William Jolitz.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 /*
42  * 386 Trap and System call handling
43  */
44 
45 #include "opt_clock.h"
46 #include "opt_cpu.h"
47 #include "opt_isa.h"
48 #include "opt_ktrace.h"
49 
50 #include <sys/param.h>
51 #include <sys/bus.h>
52 #include <sys/systm.h>
53 #include <sys/proc.h>
54 #include <sys/pioctl.h>
55 #include <sys/kernel.h>
56 #include <sys/ktr.h>
57 #include <sys/lock.h>
58 #include <sys/mutex.h>
59 #include <sys/proc.h>
60 #include <sys/ptrace.h>
61 #include <sys/resourcevar.h>
62 #include <sys/signalvar.h>
63 #include <sys/syscall.h>
64 #include <sys/sysctl.h>
65 #include <sys/sysent.h>
66 #include <sys/uio.h>
67 #include <sys/vmmeter.h>
68 #ifdef KTRACE
69 #include <sys/ktrace.h>
70 #endif
71 #include <security/audit/audit.h>
72 
73 #include <vm/vm.h>
74 #include <vm/vm_param.h>
75 #include <vm/pmap.h>
76 #include <vm/vm_kern.h>
77 #include <vm/vm_map.h>
78 #include <vm/vm_page.h>
79 #include <vm/vm_extern.h>
80 
81 #include <machine/cpu.h>
82 #include <machine/intr_machdep.h>
83 #include <machine/md_var.h>
84 
85 #include <compat/freebsd32/freebsd32_util.h>
86 
87 #define	IDTVEC(name)	__CONCAT(X,name)
88 
89 extern inthand_t IDTVEC(int0x80_syscall), IDTVEC(rsvd);
90 
91 void ia32_syscall(struct trapframe *frame);	/* Called from asm code */
92 
93 void
94 ia32_set_syscall_retval(struct thread *td, int error)
95 {
96 
97 	cpu_set_syscall_retval(td, error);
98 }
99 
100 int
101 ia32_fetch_syscall_args(struct thread *td, struct syscall_args *sa)
102 {
103 	struct proc *p;
104 	struct trapframe *frame;
105 	caddr_t params;
106 	u_int32_t args[8];
107 	int error, i;
108 
109 	p = td->td_proc;
110 	frame = td->td_frame;
111 
112 	params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t);
113 	sa->code = frame->tf_rax;
114 
115 	/*
116 	 * Need to check if this is a 32 bit or 64 bit syscall.
117 	 */
118 	if (sa->code == SYS_syscall) {
119 		/*
120 		 * Code is first argument, followed by actual args.
121 		 */
122 		sa->code = fuword32(params);
123 		params += sizeof(int);
124 	} else if (sa->code == SYS___syscall) {
125 		/*
126 		 * Like syscall, but code is a quad, so as to maintain
127 		 * quad alignment for the rest of the arguments.
128 		 * We use a 32-bit fetch in case params is not
129 		 * aligned.
130 		 */
131 		sa->code = fuword32(params);
132 		params += sizeof(quad_t);
133 	}
134  	if (p->p_sysent->sv_mask)
135  		sa->code &= p->p_sysent->sv_mask;
136  	if (sa->code >= p->p_sysent->sv_size)
137  		sa->callp = &p->p_sysent->sv_table[0];
138   	else
139  		sa->callp = &p->p_sysent->sv_table[sa->code];
140 	sa->narg = sa->callp->sy_narg;
141 
142 	if (params != NULL && sa->narg != 0)
143 		error = copyin(params, (caddr_t)args,
144 		    (u_int)(sa->narg * sizeof(int)));
145 	else
146 		error = 0;
147 
148 	for (i = 0; i < sa->narg; i++)
149 		sa->args[i] = args[i];
150 
151 	if (error == 0) {
152 		td->td_retval[0] = 0;
153 		td->td_retval[1] = frame->tf_rdx;
154 	}
155 
156 	return (error);
157 }
158 
159 void
160 ia32_syscall(struct trapframe *frame)
161 {
162 	struct thread *td;
163 	struct syscall_args sa;
164 	register_t orig_tf_rflags;
165 	int error;
166 	ksiginfo_t ksi;
167 
168 	orig_tf_rflags = frame->tf_rflags;
169 	td = curthread;
170 	td->td_frame = frame;
171 
172 	error = syscallenter(td, &sa);
173 
174 	/*
175 	 * Traced syscall.
176 	 */
177 	if (orig_tf_rflags & PSL_T) {
178 		frame->tf_rflags &= ~PSL_T;
179 		ksiginfo_init_trap(&ksi);
180 		ksi.ksi_signo = SIGTRAP;
181 		ksi.ksi_code = TRAP_TRACE;
182 		ksi.ksi_addr = (void *)frame->tf_rip;
183 		trapsignal(td, &ksi);
184 	}
185 
186 	syscallret(td, error, &sa);
187 }
188 
189 static void
190 ia32_syscall_enable(void *dummy)
191 {
192 
193  	setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0);
194 }
195 
196 static void
197 ia32_syscall_disable(void *dummy)
198 {
199 
200  	setidt(IDT_SYSCALL, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
201 }
202 
203 SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL);
204 SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL);
205