1 /* $NetBSD: process_machdep.c,v 1.31 2020/08/10 09:38:48 rin Exp $ */
2
3 /*
4 * Copyright (c) 1993 Christopher G. Demetriou
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Christopher G. Demetriou.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 /*
34 * This file may seem a bit stylized, but that so that it's easier to port.
35 * Functions to be implemented here are:
36 *
37 * process_read_regs(proc, regs)
38 * Get the current user-visible register set from the process
39 * and copy it into the regs structure (<machine/reg.h>).
40 * The process is stopped at the time read_regs is called.
41 *
42 * process_write_regs(proc, regs)
43 * Update the current register set from the passed in regs
44 * structure. Take care to avoid clobbering special CPU
45 * registers or privileged bits in the PSL.
46 * The process is stopped at the time write_regs is called.
47 *
48 * process_sstep(proc)
49 * Arrange for the process to trap after executing a single instruction.
50 *
51 * process_set_pc(proc)
52 * Set the process's program counter.
53 */
54
55 #include <sys/cdefs.h>
56 __KERNEL_RCSID(0, "$NetBSD: process_machdep.c,v 1.31 2020/08/10 09:38:48 rin Exp $");
57
58 #include <sys/param.h>
59 #include <sys/systm.h>
60 #include <sys/kernel.h>
61 #include <sys/proc.h>
62 #include <sys/vnode.h>
63 #include <sys/ptrace.h>
64
65 #include <machine/frame.h>
66 #include <machine/pcb.h>
67 #include <machine/psl.h>
68
69 static inline struct frame *
process_frame(struct lwp * l)70 process_frame(struct lwp *l)
71 {
72 void *ptr;
73
74 ptr = l->l_md.md_regs;
75 return ptr;
76 }
77
78 static inline struct fpframe *
process_fpframe(struct lwp * l)79 process_fpframe(struct lwp *l)
80 {
81 struct pcb *pcb = lwp_getpcb(l);
82
83 return &pcb->pcb_fpregs;
84 }
85
86 int
process_read_regs(struct lwp * l,struct reg * regs)87 process_read_regs(struct lwp *l, struct reg *regs)
88 {
89 struct frame *frame = process_frame(l);
90
91 memcpy(regs->r_regs, frame->f_regs, sizeof(frame->f_regs));
92 regs->r_sr = frame->f_sr;
93 regs->r_pc = frame->f_pc;
94
95 return 0;
96 }
97
98 int
process_read_fpregs(struct lwp * l,struct fpreg * regs,size_t * sz)99 process_read_fpregs(struct lwp *l, struct fpreg *regs, size_t *sz)
100 {
101 struct fpframe *frame = process_fpframe(l);
102
103 memcpy(regs->r_regs, frame->fpf_regs, sizeof(frame->fpf_regs));
104 regs->r_fpcr = frame->fpf_fpcr;
105 regs->r_fpsr = frame->fpf_fpsr;
106 regs->r_fpiar = frame->fpf_fpiar;
107
108 return 0;
109 }
110
111 int
process_write_regs(struct lwp * l,const struct reg * regs)112 process_write_regs(struct lwp *l, const struct reg *regs)
113 {
114 struct frame *frame = process_frame(l);
115
116 /*
117 * Avoid kernel address error at rte instruction.
118 */
119 if (regs->r_pc & 1)
120 return EINVAL;
121
122 /*
123 * XXX
124 * in hp300 machdep.c, it just cleared/set these bits
125 * automatically. here, we barf. well-written programs
126 * shouldn't munge them.
127 */
128 if ((regs->r_sr & PSL_USERCLR) != 0 ||
129 (regs->r_sr & PSL_USERSET) != PSL_USERSET)
130 return EPERM;
131
132 memcpy(frame->f_regs, regs->r_regs, sizeof(frame->f_regs));
133 frame->f_sr = regs->r_sr;
134 frame->f_pc = regs->r_pc;
135
136 return 0;
137 }
138
139 int
process_write_fpregs(struct lwp * l,const struct fpreg * regs,size_t sz)140 process_write_fpregs(struct lwp *l, const struct fpreg *regs, size_t sz)
141 {
142 struct fpframe *frame = process_fpframe(l);
143
144 memcpy(frame->fpf_regs, regs->r_regs, sizeof(frame->fpf_regs));
145 frame->fpf_fpcr = regs->r_fpcr;
146 frame->fpf_fpsr = regs->r_fpsr;
147 frame->fpf_fpiar = regs->r_fpiar;
148
149 return 0;
150 }
151
152 int
process_sstep(struct lwp * l,int sstep)153 process_sstep(struct lwp *l, int sstep)
154 {
155 struct frame *frame = process_frame(l);
156
157 if (sstep)
158 frame->f_sr |= PSL_T;
159 else
160 frame->f_sr &= ~PSL_T;
161
162 return 0;
163 }
164
165 int
process_set_pc(struct lwp * l,void * addr)166 process_set_pc(struct lwp *l, void *addr)
167 {
168 struct frame *frame = process_frame(l);
169
170 /*
171 * Avoid kernel address error at rte instruction.
172 */
173 if ((u_int)addr & 1)
174 return EINVAL;
175 frame->f_pc = (u_int)addr;
176
177 return 0;
178 }
179