1/*
2 * Copyright 1998 Sean Eric Fagan
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 * 3. All advertising materials mentioning features or use of this software
13 *    must display the following acknowledgement:
14 *	This product includes software developed by Sean Eric Fagan
15 * 4. Neither the name of the author may be used to endorse or promote
16 *    products derived from this software without specific prior written
17 *    permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD$");
34
35/* FreeBSD/mips-specific system call handling. */
36
37#include <sys/ptrace.h>
38#include <sys/syscall.h>
39
40#include <machine/frame.h>
41#include <machine/reg.h>
42
43#include <stdio.h>
44
45#include "truss.h"
46
47#include "syscalls.h"
48
49static int
50mips_fetch_args(struct trussinfo *trussinfo, u_int narg)
51{
52	struct ptrace_io_desc iorequest;
53	struct reg regs;
54	struct current_syscall *cs;
55	lwpid_t tid;
56	u_int i, reg;
57
58	tid = trussinfo->curthread->tid;
59	cs = &trussinfo->curthread->cs;
60	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
61		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
62		return (-1);
63	}
64
65	/*
66	 * FreeBSD has two special kinds of system call redirections --
67	 * SYS_syscall, and SYS___syscall.  The former is the old syscall()
68	 * routine, basically; the latter is for quad-aligned arguments.
69	 *
70	 * The system call argument count and code from ptrace() already
71	 * account for these, but we need to skip over the first argument.
72	 */
73	reg = A0;
74	switch (regs.r_regs[V0]) {
75	case SYS_syscall:
76		reg = A1;
77		break;
78	case SYS___syscall:
79#if defined(__mips_n32) || defined(__mips_n64)
80		reg = A1;
81#else
82		reg = A2;
83#endif
84		break;
85	}
86
87#if defined(__mips_n32) || defined(__mips_n64)
88#define	MAXREG		A7
89#else
90#define	MAXREG		A3
91#endif
92
93	for (i = 0; i < narg && reg <= MAXREG; i++, reg++)
94		cs->args[i] = regs.r_regs[reg];
95	if (narg > i) {
96		iorequest.piod_op = PIOD_READ_D;
97		iorequest.piod_offs = (void *)((uintptr_t)regs.r_regs[SP] +
98		    4 * sizeof(cs->args[0]));
99		iorequest.piod_addr = &cs->args[i];
100		iorequest.piod_len = (narg - i) * sizeof(cs->args[0]);
101		ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
102		if (iorequest.piod_len == 0)
103			return (-1);
104	}
105
106	return (0);
107}
108
109static int
110mips_fetch_retval(struct trussinfo *trussinfo, long *retval, int *errorp)
111{
112	struct reg regs;
113	lwpid_t tid;
114
115	tid = trussinfo->curthread->tid;
116	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
117		fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
118		return (-1);
119	}
120
121	/* XXX: Does not have special handling for __syscall(). */
122	retval[0] = regs.r_regs[V0];
123	retval[1] = regs.r_regs[V1];
124	*errorp = !!regs.r_regs[A3];
125	return (0);
126}
127
128
129static struct procabi mips_fbsd = {
130#ifdef __mips_n64
131	"FreeBSD ELF64",
132#else
133	"FreeBSD ELF32",
134#endif
135	syscallnames,
136	nitems(syscallnames),
137	mips_fetch_args,
138	mips_fetch_retval
139};
140
141PROCABI(mips_fbsd);
142