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 * $FreeBSD$ 27 */ 28 29 /* 30 * Author: David B. Golub, Carnegie Mellon University 31 * Date: 7/90 32 */ 33 /* 34 * Breakpoints. 35 */ 36 #include <sys/param.h> 37 38 #include <vm/vm.h> 39 #include <vm/vm_kern.h> 40 41 #include <ddb/ddb.h> 42 #include <ddb/db_break.h> 43 #include <ddb/db_access.h> 44 #include <ddb/db_sym.h> 45 46 #define NBREAKPOINTS 100 47 static struct db_breakpoint db_break_table[NBREAKPOINTS]; 48 static db_breakpoint_t db_next_free_breakpoint = &db_break_table[0]; 49 static db_breakpoint_t db_free_breakpoints = 0; 50 static db_breakpoint_t db_breakpoint_list = 0; 51 52 static db_breakpoint_t db_breakpoint_alloc __P((void)); 53 static void db_breakpoint_free __P((db_breakpoint_t bkpt)); 54 static void db_delete_breakpoint __P((vm_map_t map, db_addr_t addr)); 55 static db_breakpoint_t db_find_breakpoint __P((vm_map_t map, db_addr_t addr)); 56 static void db_list_breakpoints __P((void)); 57 static void db_set_breakpoint __P((vm_map_t map, db_addr_t addr, 58 int count)); 59 60 static db_breakpoint_t 61 db_breakpoint_alloc() 62 { 63 register db_breakpoint_t bkpt; 64 65 if ((bkpt = db_free_breakpoints) != 0) { 66 db_free_breakpoints = bkpt->link; 67 return (bkpt); 68 } 69 if (db_next_free_breakpoint == &db_break_table[NBREAKPOINTS]) { 70 db_printf("All breakpoints used.\n"); 71 return (0); 72 } 73 bkpt = db_next_free_breakpoint; 74 db_next_free_breakpoint++; 75 76 return (bkpt); 77 } 78 79 static void 80 db_breakpoint_free(bkpt) 81 register db_breakpoint_t bkpt; 82 { 83 bkpt->link = db_free_breakpoints; 84 db_free_breakpoints = bkpt; 85 } 86 87 static void 88 db_set_breakpoint(map, addr, count) 89 vm_map_t map; 90 db_addr_t addr; 91 int count; 92 { 93 register db_breakpoint_t bkpt; 94 95 if (db_find_breakpoint(map, addr)) { 96 db_printf("Already set.\n"); 97 return; 98 } 99 100 bkpt = db_breakpoint_alloc(); 101 if (bkpt == 0) { 102 db_printf("Too many breakpoints.\n"); 103 return; 104 } 105 106 bkpt->map = map; 107 bkpt->address = addr; 108 bkpt->flags = 0; 109 bkpt->init_count = count; 110 bkpt->count = count; 111 112 bkpt->link = db_breakpoint_list; 113 db_breakpoint_list = bkpt; 114 } 115 116 static void 117 db_delete_breakpoint(map, addr) 118 vm_map_t map; 119 db_addr_t addr; 120 { 121 register db_breakpoint_t bkpt; 122 register db_breakpoint_t *prev; 123 124 for (prev = &db_breakpoint_list; 125 (bkpt = *prev) != 0; 126 prev = &bkpt->link) { 127 if (db_map_equal(bkpt->map, map) && 128 (bkpt->address == addr)) { 129 *prev = bkpt->link; 130 break; 131 } 132 } 133 if (bkpt == 0) { 134 db_printf("Not set.\n"); 135 return; 136 } 137 138 db_breakpoint_free(bkpt); 139 } 140 141 static db_breakpoint_t 142 db_find_breakpoint(map, addr) 143 vm_map_t map; 144 db_addr_t addr; 145 { 146 register db_breakpoint_t bkpt; 147 148 for (bkpt = db_breakpoint_list; 149 bkpt != 0; 150 bkpt = bkpt->link) 151 { 152 if (db_map_equal(bkpt->map, map) && 153 (bkpt->address == addr)) 154 return (bkpt); 155 } 156 return (0); 157 } 158 159 db_breakpoint_t 160 db_find_breakpoint_here(addr) 161 db_addr_t addr; 162 { 163 return db_find_breakpoint(db_map_addr(addr), addr); 164 } 165 166 static boolean_t db_breakpoints_inserted = TRUE; 167 168 void 169 db_set_breakpoints() 170 { 171 register db_breakpoint_t bkpt; 172 173 if (!db_breakpoints_inserted) { 174 175 for (bkpt = db_breakpoint_list; 176 bkpt != 0; 177 bkpt = bkpt->link) 178 if (db_map_current(bkpt->map)) { 179 bkpt->bkpt_inst = db_get_value(bkpt->address, 180 BKPT_SIZE, 181 FALSE); 182 db_put_value(bkpt->address, 183 BKPT_SIZE, 184 BKPT_SET(bkpt->bkpt_inst)); 185 } 186 db_breakpoints_inserted = TRUE; 187 } 188 } 189 190 void 191 db_clear_breakpoints() 192 { 193 register db_breakpoint_t bkpt; 194 195 if (db_breakpoints_inserted) { 196 197 for (bkpt = db_breakpoint_list; 198 bkpt != 0; 199 bkpt = bkpt->link) 200 if (db_map_current(bkpt->map)) { 201 db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst); 202 } 203 db_breakpoints_inserted = FALSE; 204 } 205 } 206 207 #ifdef SOFTWARE_SSTEP 208 /* 209 * Set a temporary breakpoint. 210 * The instruction is changed immediately, 211 * so the breakpoint does not have to be on the breakpoint list. 212 */ 213 db_breakpoint_t 214 db_set_temp_breakpoint(addr) 215 db_addr_t addr; 216 { 217 register db_breakpoint_t bkpt; 218 219 bkpt = db_breakpoint_alloc(); 220 if (bkpt == 0) { 221 db_printf("Too many breakpoints.\n"); 222 return 0; 223 } 224 225 bkpt->map = NULL; 226 bkpt->address = addr; 227 bkpt->flags = BKPT_TEMP; 228 bkpt->init_count = 1; 229 bkpt->count = 1; 230 231 bkpt->bkpt_inst = db_get_value(bkpt->address, BKPT_SIZE, FALSE); 232 db_put_value(bkpt->address, BKPT_SIZE, BKPT_SET(bkpt->bkpt_inst)); 233 return bkpt; 234 } 235 236 void 237 db_delete_temp_breakpoint(bkpt) 238 db_breakpoint_t bkpt; 239 { 240 db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst); 241 db_breakpoint_free(bkpt); 242 } 243 #endif /* SOFTWARE_SSTEP */ 244 245 /* 246 * List breakpoints. 247 */ 248 static void 249 db_list_breakpoints() 250 { 251 register db_breakpoint_t bkpt; 252 253 if (db_breakpoint_list == 0) { 254 db_printf("No breakpoints set\n"); 255 return; 256 } 257 258 db_printf(" Map Count Address\n"); 259 for (bkpt = db_breakpoint_list; 260 bkpt != 0; 261 bkpt = bkpt->link) { 262 db_printf("%s%8p %5d ", 263 db_map_current(bkpt->map) ? "*" : " ", 264 (void *)bkpt->map, bkpt->init_count); 265 db_printsym(bkpt->address, DB_STGY_PROC); 266 db_printf("\n"); 267 } 268 } 269 270 /* Delete breakpoint */ 271 /*ARGSUSED*/ 272 void 273 db_delete_cmd(addr, have_addr, count, modif) 274 db_expr_t addr; 275 boolean_t have_addr; 276 db_expr_t count; 277 char * modif; 278 { 279 db_delete_breakpoint(db_map_addr(addr), (db_addr_t)addr); 280 } 281 282 /* Set breakpoint with skip count */ 283 /*ARGSUSED*/ 284 void 285 db_breakpoint_cmd(addr, have_addr, count, modif) 286 db_expr_t addr; 287 boolean_t have_addr; 288 db_expr_t count; 289 char * modif; 290 { 291 if (count == -1) 292 count = 1; 293 294 db_set_breakpoint(db_map_addr(addr), (db_addr_t)addr, count); 295 } 296 297 /* list breakpoints */ 298 void 299 db_listbreak_cmd(dummy1, dummy2, dummy3, dummy4) 300 db_expr_t dummy1; 301 boolean_t dummy2; 302 db_expr_t dummy3; 303 char * dummy4; 304 { 305 db_list_breakpoints(); 306 } 307 308 /* 309 * We want ddb to be usable before most of the kernel has been 310 * initialized. In particular, current_thread() or kernel_map 311 * (or both) may be null. 312 */ 313 314 boolean_t 315 db_map_equal(map1, map2) 316 vm_map_t map1, map2; 317 { 318 return ((map1 == map2) || 319 ((map1 == NULL) && (map2 == kernel_map)) || 320 ((map1 == kernel_map) && (map2 == NULL))); 321 } 322 323 boolean_t 324 db_map_current(map) 325 vm_map_t map; 326 { 327 #if 0 328 thread_t thread; 329 330 return ((map == NULL) || 331 (map == kernel_map) || 332 (((thread = current_thread()) != NULL) && 333 (map == thread->task->map))); 334 #else 335 return (1); 336 #endif 337 } 338 339 vm_map_t 340 db_map_addr(addr) 341 vm_offset_t addr; 342 { 343 #if 0 344 thread_t thread; 345 346 /* 347 * We want to return kernel_map for all 348 * non-user addresses, even when debugging 349 * kernel tasks with their own maps. 350 */ 351 352 if ((VM_MIN_ADDRESS <= addr) && 353 (addr < VM_MAX_ADDRESS) && 354 ((thread = current_thread()) != NULL)) 355 return thread->task->map; 356 else 357 #endif 358 return kernel_map; 359 } 360