- Port rtw(4) from NetBSD, which supports various RealTek 8180 chip based
[dragonfly.git] / sys / ddb / db_watch.c
1 /*
2  * Mach Operating System
3  * Copyright (c) 1991,1990 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie the
24  * rights to redistribute these changes.
25  *
26  * $FreeBSD: src/sys/ddb/db_watch.c,v 1.20.2.1 2001/07/25 01:00:08 bsd Exp $
27  * $DragonFly: src/sys/ddb/db_watch.c,v 1.5 2005/12/23 21:35:44 swildner Exp $
28  */
29
30 /*
31  *      Author: Richard P. Draves, Carnegie Mellon University
32  *      Date:   10/90
33  */
34
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37
38 #include <vm/vm.h>
39 #include <sys/lock.h>
40 #include <vm/pmap.h>
41 #include <vm/vm_map.h>
42
43 #include <ddb/ddb.h>
44 #include <ddb/db_watch.h>
45
46 /*
47  * Watchpoints.
48  */
49
50 static boolean_t        db_watchpoints_inserted = TRUE;
51
52 #define NWATCHPOINTS    100
53 static struct db_watchpoint     db_watch_table[NWATCHPOINTS];
54 static db_watchpoint_t  db_next_free_watchpoint = &db_watch_table[0];
55 static db_watchpoint_t  db_free_watchpoints = 0;
56 static db_watchpoint_t  db_watchpoint_list = 0;
57
58 static db_watchpoint_t  db_watchpoint_alloc (void);
59 static void             db_watchpoint_free (db_watchpoint_t watch);
60 static void             db_delete_watchpoint (vm_map_t map,
61                                         db_addr_t addr);
62 #ifdef notused
63 static boolean_t        db_find_watchpoint (vm_map_t map, db_addr_t addr,
64                                         db_regs_t *regs);
65 #endif
66 static void             db_list_watchpoints (void);
67 static void             db_set_watchpoint (vm_map_t map, db_addr_t addr,
68                                        vm_size_t size);
69
70 int  db_md_set_watchpoint   (db_expr_t addr, db_expr_t size);
71 int  db_md_clr_watchpoint   (db_expr_t addr, db_expr_t size);
72 void db_md_list_watchpoints (void);
73
74
75 db_watchpoint_t
76 db_watchpoint_alloc(void)
77 {
78         db_watchpoint_t watch;
79
80         if ((watch = db_free_watchpoints) != 0) {
81             db_free_watchpoints = watch->link;
82             return (watch);
83         }
84         if (db_next_free_watchpoint == &db_watch_table[NWATCHPOINTS]) {
85             db_printf("All watchpoints used.\n");
86             return (0);
87         }
88         watch = db_next_free_watchpoint;
89         db_next_free_watchpoint++;
90
91         return (watch);
92 }
93
94 void
95 db_watchpoint_free(db_watchpoint_t watch)
96 {
97         watch->link = db_free_watchpoints;
98         db_free_watchpoints = watch;
99 }
100
101 static void
102 db_set_watchpoint(vm_map_t map, db_addr_t addr, vm_size_t size)
103 {
104         db_watchpoint_t watch;
105
106         if (map == NULL) {
107             db_printf("No map.\n");
108             return;
109         }
110
111         /*
112          *      Should we do anything fancy with overlapping regions?
113          */
114
115         for (watch = db_watchpoint_list;
116              watch != 0;
117              watch = watch->link)
118             if (db_map_equal(watch->map, map) &&
119                 (watch->loaddr == addr) &&
120                 (watch->hiaddr == addr+size)) {
121                 db_printf("Already set.\n");
122                 return;
123             }
124
125         watch = db_watchpoint_alloc();
126         if (watch == 0) {
127             db_printf("Too many watchpoints.\n");
128             return;
129         }
130
131         watch->map = map;
132         watch->loaddr = addr;
133         watch->hiaddr = addr+size;
134
135         watch->link = db_watchpoint_list;
136         db_watchpoint_list = watch;
137
138         db_watchpoints_inserted = FALSE;
139 }
140
141 static void
142 db_delete_watchpoint(vm_map_t map, db_addr_t addr)
143 {
144         db_watchpoint_t watch;
145         db_watchpoint_t *prev;
146
147         for (prev = &db_watchpoint_list;
148              (watch = *prev) != 0;
149              prev = &watch->link)
150             if (db_map_equal(watch->map, map) &&
151                 (watch->loaddr <= addr) &&
152                 (addr < watch->hiaddr)) {
153                 *prev = watch->link;
154                 db_watchpoint_free(watch);
155                 return;
156             }
157
158         db_printf("Not set.\n");
159 }
160
161 static void
162 db_list_watchpoints(void)
163 {
164         db_watchpoint_t watch;
165
166         if (db_watchpoint_list == 0) {
167             db_printf("No watchpoints set\n");
168             return;
169         }
170
171         db_printf(" Map        Address  Size\n");
172         for (watch = db_watchpoint_list;
173              watch != 0;
174              watch = watch->link)
175             db_printf("%s%8p  %8lx  %lx\n",
176                       db_map_current(watch->map) ? "*" : " ",
177                       (void *)watch->map, (long)watch->loaddr,
178                       (long)watch->hiaddr - (long)watch->loaddr);
179 }
180
181 /* Delete watchpoint */
182 /*ARGSUSED*/
183 void
184 db_deletewatch_cmd(db_expr_t addr, boolean_t have_addr, db_expr_t count,
185                    char *modif)
186 {
187         db_delete_watchpoint(db_map_addr(addr), addr);
188 }
189
190 /* Set watchpoint */
191 /*ARGSUSED*/
192 void
193 db_watchpoint_cmd(db_expr_t addr, boolean_t have_addr, db_expr_t count,
194                   char *modif)
195 {
196         vm_size_t       size;
197         db_expr_t       value;
198
199         if (db_expression(&value))
200             size = (vm_size_t) value;
201         else
202             size = 4;
203         db_skip_to_eol();
204
205         db_set_watchpoint(db_map_addr(addr), addr, size);
206 }
207
208 /*
209  * At least one non-optional show-command must be implemented using
210  * DB_SHOW_COMMAND() so that db_show_cmd_set gets created.  Here is one.
211  */
212 DB_SHOW_COMMAND(watches, db_listwatch_cmd)
213 {
214         db_list_watchpoints();
215         db_md_list_watchpoints();
216 }
217
218 void
219 db_set_watchpoints(void)
220 {
221         db_watchpoint_t watch;
222
223         if (!db_watchpoints_inserted) {
224             for (watch = db_watchpoint_list;
225                  watch != 0;
226                  watch = watch->link)
227                 pmap_protect(watch->map->pmap,
228                              trunc_page(watch->loaddr),
229                              round_page(watch->hiaddr),
230                              VM_PROT_READ);
231
232             db_watchpoints_inserted = TRUE;
233         }
234 }
235
236 void
237 db_clear_watchpoints(void)
238 {
239         db_watchpoints_inserted = FALSE;
240 }
241
242 #ifdef notused
243 static boolean_t
244 db_find_watchpoint(vm_map_t map, db_addr_t addr, db_regs_t *regs)
245 {
246         db_watchpoint_t watch;
247         db_watchpoint_t found = 0;
248
249         for (watch = db_watchpoint_list;
250              watch != 0;
251              watch = watch->link)
252             if (db_map_equal(watch->map, map)) {
253                 if ((watch->loaddr <= addr) &&
254                     (addr < watch->hiaddr))
255                     return (TRUE);
256                 else if ((trunc_page(watch->loaddr) <= addr) &&
257                          (addr < round_page(watch->hiaddr)))
258                     found = watch;
259             }
260
261         /*
262          *      We didn't hit exactly on a watchpoint, but we are
263          *      in a protected region.  We want to single-step
264          *      and then re-protect.
265          */
266
267         if (found) {
268             db_watchpoints_inserted = FALSE;
269             db_single_step(regs);
270         }
271
272         return (FALSE);
273 }
274 #endif
275
276
277
278 /* Delete hardware watchpoint */
279 /*ARGSUSED*/
280 void
281 db_deletehwatch_cmd(db_expr_t addr, boolean_t have_addr, db_expr_t count,
282                     char *modif)
283 {
284         int rc;
285
286         if (count < 0)
287                 count = 4;
288
289         rc = db_md_clr_watchpoint(addr, count);
290         if (rc < 0)
291                 db_printf("hardware watchpoint could not be deleted\n");
292 }
293
294 /* Set hardware watchpoint */
295 /*ARGSUSED*/
296 void
297 db_hwatchpoint_cmd(db_expr_t addr, boolean_t have_addr, db_expr_t count,
298                    char *modif)
299 {
300         int rc;
301
302         if (count < 0)
303                 count = 4;
304
305         rc = db_md_set_watchpoint(addr, count);
306         if (rc < 0)
307                 db_printf("hardware watchpoint could not be set\n");
308 }