1/* $NetBSD: db_watch.c,v 1.27 2007/02/22 06:41:01 thorpej Exp $ */
2
3/*
4 * Mach Operating System
5 * Copyright (c) 1991,1990 Carnegie Mellon University
6 * All Rights Reserved.
7 *
8 * Permission to use, copy, modify and distribute this software and its
9 * documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
21 * School of Computer Science
22 * Carnegie Mellon University
23 * Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
27 *
28 * Author: Richard P. Draves, Carnegie Mellon University
29 * Date: 10/90
30 */
31
32#include <sys/cdefs.h>
33__KERNEL_RCSID(0, "$NetBSD: db_watch.c,v 1.27 2007/02/22 06:41:01 thorpej Exp $");
34
35#include <sys/param.h>
36#include <sys/proc.h>
37
38#include <machine/db_machdep.h>
39
40#include <ddb/db_break.h>
41#include <ddb/db_watch.h>
42#include <ddb/db_lex.h>
43#include <ddb/db_access.h>
44#include <ddb/db_run.h>
45#include <ddb/db_sym.h>
46#include <ddb/db_output.h>
47#include <ddb/db_command.h>
48#include <ddb/db_extern.h>
49
50/*
51 * Watchpoints.
52 */
53
54static bool db_watchpoints_inserted = true;
55
56#define NWATCHPOINTS 100
57static struct db_watchpoint db_watch_table[NWATCHPOINTS];
58static db_watchpoint_t db_next_free_watchpoint = &db_watch_table[0];
59static db_watchpoint_t db_free_watchpoints = 0;
60static db_watchpoint_t db_watchpoint_list = 0;
61
62static void db_delete_watchpoint(struct vm_map *, db_addr_t);
63static void db_list_watchpoints(void);
64static void db_set_watchpoint(struct vm_map *, db_addr_t, vsize_t);
65static db_watchpoint_t db_watchpoint_alloc(void);
66static void db_watchpoint_free(db_watchpoint_t);
67
68db_watchpoint_t
69db_watchpoint_alloc(void)
70{
71 db_watchpoint_t watch;
72
73 if ((watch = db_free_watchpoints) != 0) {
74 db_free_watchpoints = watch->link;
75 return (watch);
76 }
77 if (db_next_free_watchpoint == &db_watch_table[NWATCHPOINTS]) {
78 db_printf("All watchpoints used.\n");
79 return (0);
80 }
81 watch = db_next_free_watchpoint;
82 db_next_free_watchpoint++;
83
84 return (watch);
85}
86
87void
88db_watchpoint_free(db_watchpoint_t watch)
89{
90 watch->link = db_free_watchpoints;
91 db_free_watchpoints = watch;
92}
93
94void
95db_set_watchpoint(struct vm_map *map, db_addr_t addr, vsize_t size)
96{
97 db_watchpoint_t watch;
98
99 if (map == NULL) {
100 db_printf("No map.\n");
101 return;
102 }
103
104 /*
105 * Should we do anything fancy with overlapping regions?
106 */
107
108 for (watch = db_watchpoint_list; watch != 0; watch = watch->link)
109 if (db_map_equal(watch->map, map) &&
110 (watch->loaddr == addr) &&
111 (watch->hiaddr == addr+size)) {
112 db_printf("Already set.\n");
113 return;
114 }
115
116 watch = db_watchpoint_alloc();
117 if (watch == 0) {
118 db_printf("Too many watchpoints.\n");
119 return;
120 }
121
122 watch->map = map;
123 watch->loaddr = addr;
124 watch->hiaddr = addr+size;
125
126 watch->link = db_watchpoint_list;
127 db_watchpoint_list = watch;
128
129 db_watchpoints_inserted = false;
130}
131
132static void
133db_delete_watchpoint(struct vm_map *map, db_addr_t addr)
134{
135 db_watchpoint_t watch;
136 db_watchpoint_t *prev;
137
138 for (prev = &db_watchpoint_list;
139 (watch = *prev) != 0;
140 prev = &watch->link)
141 if (db_map_equal(watch->map, map) &&
142 (watch->loaddr <= addr) &&
143 (addr < watch->hiaddr)) {
144 *prev = watch->link;
145 db_watchpoint_free(watch);
146 return;
147 }
148
149 db_printf("Not set.\n");
150}
151
152void
153db_list_watchpoints(void)
154{
155 db_watchpoint_t watch;
156
157 if (db_watchpoint_list == 0) {
158 db_printf("No watchpoints set\n");
159 return;
160 }
161
162 db_printf(" Map Address Size\n");
163 for (watch = db_watchpoint_list; watch != 0; watch = watch->link)
164 db_printf("%s%p %8lx %lx\n",
165 db_map_current(watch->map) ? "*" : " ",
166 watch->map, (long)watch->loaddr,
167 (long)(watch->hiaddr - watch->loaddr));
168}
169
170/* Delete watchpoint */
171/*ARGSUSED*/
172void
173db_deletewatch_cmd(db_expr_t addr, bool have_addr,
174 db_expr_t count, const char *modif)
175{
176
177 db_delete_watchpoint(db_map_addr(addr), addr);
178}
179
180/* Set watchpoint */
181/*ARGSUSED*/
182void
183db_watchpoint_cmd(db_expr_t addr, bool have_addr,
184 db_expr_t count, const char *modif)
185{
186 vsize_t size;
187 db_expr_t value;
188
189 if (db_expression(&value))
190 size = (vsize_t) value;
191 else
192 size = 4;
193 db_skip_to_eol();
194
195 db_set_watchpoint(db_map_addr(addr), addr, size);
196}
197
198/* list watchpoints */
199/*ARGSUSED*/
200void
201db_listwatch_cmd(db_expr_t addr, bool have_addr,
202 db_expr_t count, const char *modif)
203{
204
205 db_list_watchpoints();
206}
207
208void
209db_set_watchpoints(void)
210{
211 db_watchpoint_t watch;
212
213 if (!db_watchpoints_inserted) {
214 for (watch = db_watchpoint_list;
215 watch != 0;
216 watch = watch->link) {
217 pmap_protect(watch->map->pmap,
218 trunc_page(watch->loaddr),
219 round_page(watch->hiaddr),
220 VM_PROT_READ);
221 pmap_update(watch->map->pmap);
222 }
223
224 db_watchpoints_inserted = true;
225 }
226}
227
228void
229db_clear_watchpoints(void)
230{
231
232 db_watchpoints_inserted = false;
233}
234