2 * SPDX-License-Identifier: MIT-CMU
4 * Mach Operating System
5 * Copyright (c) 1991,1990 Carnegie Mellon University
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.
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 * Carnegie Mellon requests users of this software to return to
20 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
21 * School of Computer Science
22 * Carnegie Mellon University
23 * Pittsburgh PA 15213-3890
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
30 * Author: David B. Golub, Carnegie Mellon University
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include <sys/param.h>
43 #include <vm/vm_kern.h>
46 #include <ddb/db_break.h>
47 #include <ddb/db_access.h>
48 #include <ddb/db_sym.h>
50 #define NBREAKPOINTS 100
51 static struct db_breakpoint db_break_table[NBREAKPOINTS];
52 static db_breakpoint_t db_next_free_breakpoint = &db_break_table[0];
53 static db_breakpoint_t db_free_breakpoints = 0;
54 static db_breakpoint_t db_breakpoint_list = 0;
56 static db_breakpoint_t db_breakpoint_alloc(void);
57 static void db_breakpoint_free(db_breakpoint_t bkpt);
58 static void db_delete_breakpoint(vm_map_t map, db_addr_t addr);
59 static db_breakpoint_t db_find_breakpoint(vm_map_t map, db_addr_t addr);
60 static void db_list_breakpoints(void);
61 static void db_set_breakpoint(vm_map_t map, db_addr_t addr, int count);
63 static db_breakpoint_t
64 db_breakpoint_alloc(void)
66 register db_breakpoint_t bkpt;
68 if ((bkpt = db_free_breakpoints) != 0) {
69 db_free_breakpoints = bkpt->link;
72 if (db_next_free_breakpoint == &db_break_table[NBREAKPOINTS]) {
73 db_printf("All breakpoints used.\n");
76 bkpt = db_next_free_breakpoint;
77 db_next_free_breakpoint++;
83 db_breakpoint_free(db_breakpoint_t bkpt)
85 bkpt->link = db_free_breakpoints;
86 db_free_breakpoints = bkpt;
90 db_set_breakpoint(vm_map_t map, db_addr_t addr, int count)
92 register db_breakpoint_t bkpt;
94 if (db_find_breakpoint(map, addr)) {
95 db_printf("Already set.\n");
99 bkpt = db_breakpoint_alloc();
101 db_printf("Too many breakpoints.\n");
106 bkpt->address = addr;
108 bkpt->init_count = count;
111 bkpt->link = db_breakpoint_list;
112 db_breakpoint_list = bkpt;
116 db_delete_breakpoint(vm_map_t map, db_addr_t addr)
118 register db_breakpoint_t bkpt;
119 register db_breakpoint_t *prev;
121 for (prev = &db_breakpoint_list;
123 prev = &bkpt->link) {
124 if (db_map_equal(bkpt->map, map) &&
125 (bkpt->address == addr)) {
131 db_printf("Not set.\n");
135 db_breakpoint_free(bkpt);
138 static db_breakpoint_t
139 db_find_breakpoint(vm_map_t map, db_addr_t addr)
141 register db_breakpoint_t bkpt;
143 for (bkpt = db_breakpoint_list;
147 if (db_map_equal(bkpt->map, map) &&
148 (bkpt->address == addr))
155 db_find_breakpoint_here(db_addr_t addr)
157 return db_find_breakpoint(db_map_addr(addr), addr);
160 static bool db_breakpoints_inserted = true;
163 #define BKPT_WRITE(addr, storage) \
165 *storage = db_get_value(addr, BKPT_SIZE, false); \
166 db_put_value(addr, BKPT_SIZE, BKPT_SET(*storage)); \
171 #define BKPT_CLEAR(addr, storage) \
172 db_put_value(addr, BKPT_SIZE, *storage)
176 db_set_breakpoints(void)
178 register db_breakpoint_t bkpt;
180 if (!db_breakpoints_inserted) {
182 for (bkpt = db_breakpoint_list;
185 if (db_map_current(bkpt->map)) {
186 BKPT_WRITE(bkpt->address, &bkpt->bkpt_inst);
188 db_breakpoints_inserted = true;
193 db_clear_breakpoints(void)
195 register db_breakpoint_t bkpt;
197 if (db_breakpoints_inserted) {
199 for (bkpt = db_breakpoint_list;
202 if (db_map_current(bkpt->map)) {
203 BKPT_CLEAR(bkpt->address, &bkpt->bkpt_inst);
205 db_breakpoints_inserted = false;
209 #ifdef SOFTWARE_SSTEP
211 * Set a temporary breakpoint.
212 * The instruction is changed immediately,
213 * so the breakpoint does not have to be on the breakpoint list.
216 db_set_temp_breakpoint(db_addr_t addr)
218 register db_breakpoint_t bkpt;
220 bkpt = db_breakpoint_alloc();
222 db_printf("Too many breakpoints.\n");
227 bkpt->address = addr;
228 bkpt->flags = BKPT_TEMP;
229 bkpt->init_count = 1;
232 BKPT_WRITE(bkpt->address, &bkpt->bkpt_inst);
237 db_delete_temp_breakpoint(db_breakpoint_t bkpt)
239 BKPT_CLEAR(bkpt->address, &bkpt->bkpt_inst);
240 db_breakpoint_free(bkpt);
242 #endif /* SOFTWARE_SSTEP */
248 db_list_breakpoints(void)
250 register db_breakpoint_t bkpt;
252 if (db_breakpoint_list == 0) {
253 db_printf("No breakpoints set\n");
257 db_printf(" Map Count Address\n");
258 for (bkpt = db_breakpoint_list;
261 db_printf("%s%8p %5d ",
262 db_map_current(bkpt->map) ? "*" : " ",
263 (void *)bkpt->map, bkpt->init_count);
264 db_printsym(bkpt->address, DB_STGY_PROC);
269 /* Delete breakpoint */
272 db_delete_cmd(db_expr_t addr, bool have_addr, db_expr_t count, char *modif)
274 db_delete_breakpoint(db_map_addr(addr), (db_addr_t)addr);
277 /* Set breakpoint with skip count */
280 db_breakpoint_cmd(db_expr_t addr, bool have_addr, db_expr_t count, char *modif)
285 db_set_breakpoint(db_map_addr(addr), (db_addr_t)addr, count);
288 /* list breakpoints */
290 db_listbreak_cmd(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
292 db_list_breakpoints();
296 * We want ddb to be usable before most of the kernel has been
297 * initialized. In particular, current_thread() or kernel_map
298 * (or both) may be null.
302 db_map_equal(vm_map_t map1, vm_map_t map2)
304 return ((map1 == map2) ||
305 ((map1 == NULL) && (map2 == kernel_map)) ||
306 ((map1 == kernel_map) && (map2 == NULL)));
310 db_map_current(vm_map_t map)
315 return ((map == NULL) ||
316 (map == kernel_map) ||
317 (((thread = current_thread()) != NULL) &&
318 (map == thread->task->map)));
325 db_map_addr(vm_offset_t addr)
331 * We want to return kernel_map for all
332 * non-user addresses, even when debugging
333 * kernel tasks with their own maps.
336 if ((VM_MIN_ADDRESS <= addr) &&
337 (addr < VM_MAX_ADDRESS) &&
338 ((thread = current_thread()) != NULL))
339 return thread->task->map;