1 /* $NetBSD: db_break.c,v 1.26 2007/02/22 06:41:00 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: David B. Golub, Carnegie Mellon University 29 * Date: 7/90 30 */ 31 32 /* 33 * Breakpoints. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: db_break.c,v 1.26 2007/02/22 06:41:00 thorpej Exp $"); 38 39 #include <sys/param.h> 40 #include <sys/proc.h> 41 42 #include <machine/db_machdep.h> /* type definitions */ 43 44 #include <ddb/db_lex.h> 45 #include <ddb/db_access.h> 46 #include <ddb/db_sym.h> 47 #include <ddb/db_break.h> 48 #include <ddb/db_output.h> 49 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; 55 56 static db_breakpoint_t db_breakpoint_alloc(void); 57 static void db_breakpoint_free(db_breakpoint_t); 58 static void db_delete_breakpoint(struct vm_map *, db_addr_t); 59 static db_breakpoint_t db_find_breakpoint(struct vm_map *, db_addr_t); 60 static void db_list_breakpoints(void); 61 static void db_set_breakpoint(struct vm_map *, db_addr_t, int); 62 63 static db_breakpoint_t 64 db_breakpoint_alloc(void) 65 { 66 db_breakpoint_t bkpt; 67 68 if ((bkpt = db_free_breakpoints) != 0) { 69 db_free_breakpoints = bkpt->link; 70 return (bkpt); 71 } 72 if (db_next_free_breakpoint == &db_break_table[NBREAKPOINTS]) { 73 db_printf("All breakpoints used.\n"); 74 return (0); 75 } 76 bkpt = db_next_free_breakpoint; 77 db_next_free_breakpoint++; 78 79 return (bkpt); 80 } 81 82 static void 83 db_breakpoint_free(db_breakpoint_t bkpt) 84 { 85 bkpt->link = db_free_breakpoints; 86 db_free_breakpoints = bkpt; 87 } 88 89 void 90 db_set_breakpoint(struct vm_map *map, db_addr_t addr, int count) 91 { 92 db_breakpoint_t bkpt; 93 94 if (db_find_breakpoint(map, addr)) { 95 db_printf("Already set.\n"); 96 return; 97 } 98 99 bkpt = db_breakpoint_alloc(); 100 if (bkpt == 0) { 101 db_printf("Too many breakpoints.\n"); 102 return; 103 } 104 105 bkpt->map = map; 106 bkpt->address = BKPT_ADDR(addr); 107 bkpt->flags = 0; 108 bkpt->init_count = count; 109 bkpt->count = count; 110 111 bkpt->link = db_breakpoint_list; 112 db_breakpoint_list = bkpt; 113 } 114 115 static void 116 db_delete_breakpoint(struct vm_map *map, db_addr_t addr) 117 { 118 db_breakpoint_t bkpt; 119 db_breakpoint_t *prev; 120 121 for (prev = &db_breakpoint_list; 122 (bkpt = *prev) != 0; 123 prev = &bkpt->link) { 124 if (db_map_equal(bkpt->map, map) && 125 (bkpt->address == BKPT_ADDR(addr))) { 126 *prev = bkpt->link; 127 break; 128 } 129 } 130 if (bkpt == 0) { 131 db_printf("Not set.\n"); 132 return; 133 } 134 135 db_breakpoint_free(bkpt); 136 } 137 138 db_breakpoint_t 139 db_find_breakpoint(struct vm_map *map, db_addr_t addr) 140 { 141 db_breakpoint_t bkpt; 142 143 for (bkpt = db_breakpoint_list; 144 bkpt != 0; 145 bkpt = bkpt->link) 146 if (db_map_equal(bkpt->map, map) && 147 (bkpt->address == BKPT_ADDR(addr))) 148 return (bkpt); 149 150 return (0); 151 } 152 153 db_breakpoint_t 154 db_find_breakpoint_here(db_addr_t addr) 155 { 156 return db_find_breakpoint(db_map_addr(addr), addr); 157 } 158 159 static bool db_breakpoints_inserted = true; 160 161 void 162 db_set_breakpoints(void) 163 { 164 db_breakpoint_t bkpt; 165 166 if (!db_breakpoints_inserted) { 167 168 for (bkpt = db_breakpoint_list; 169 bkpt != 0; 170 bkpt = bkpt->link) 171 if (db_map_current(bkpt->map)) { 172 bkpt->bkpt_inst = db_get_value(bkpt->address, 173 BKPT_SIZE, false); 174 db_put_value(bkpt->address, 175 BKPT_SIZE, 176 BKPT_SET(bkpt->bkpt_inst, bkpt->address)); 177 } 178 db_breakpoints_inserted = true; 179 } 180 } 181 182 void 183 db_clear_breakpoints(void) 184 { 185 db_breakpoint_t bkpt; 186 187 if (db_breakpoints_inserted) { 188 189 for (bkpt = db_breakpoint_list; 190 bkpt != 0; 191 bkpt = bkpt->link) 192 if (db_map_current(bkpt->map)) 193 db_put_value(bkpt->address, BKPT_SIZE, 194 bkpt->bkpt_inst); 195 db_breakpoints_inserted = false; 196 } 197 } 198 199 /* 200 * List breakpoints. 201 */ 202 void 203 db_list_breakpoints(void) 204 { 205 db_breakpoint_t bkpt; 206 207 if (db_breakpoint_list == 0) { 208 db_printf("No breakpoints set\n"); 209 return; 210 } 211 212 db_printf(" Map Count Address\n"); 213 for (bkpt = db_breakpoint_list; 214 bkpt != 0; 215 bkpt = bkpt->link) { 216 db_printf("%s%p %5d ", 217 db_map_current(bkpt->map) ? "*" : " ", 218 bkpt->map, bkpt->init_count); 219 db_printsym(bkpt->address, DB_STGY_PROC, db_printf); 220 db_printf("\n"); 221 } 222 } 223 224 /* Delete breakpoint */ 225 /*ARGSUSED*/ 226 void 227 db_delete_cmd(db_expr_t addr, bool have_addr, db_expr_t count, 228 const char *modif) 229 { 230 231 db_delete_breakpoint(db_map_addr(addr), (db_addr_t)addr); 232 } 233 234 /* Set breakpoint with skip count */ 235 /*ARGSUSED*/ 236 void 237 db_breakpoint_cmd(db_expr_t addr, bool have_addr, db_expr_t count, 238 const char *modif) 239 { 240 241 if (count == -1) 242 count = 1; 243 244 db_set_breakpoint(db_map_addr(addr), (db_addr_t)addr, count); 245 } 246 247 /* list breakpoints */ 248 /*ARGSUSED*/ 249 void 250 db_listbreak_cmd(db_expr_t addr, bool have_addr, 251 db_expr_t count, const char *modif) 252 { 253 254 db_list_breakpoints(); 255 } 256 257 #include <uvm/uvm_extern.h> 258 259 /* 260 * We want ddb to be usable before most of the kernel has been 261 * initialized. In particular, current_thread() or kernel_map 262 * (or both) may be null. 263 */ 264 265 bool 266 db_map_equal(struct vm_map *map1, struct vm_map *map2) 267 { 268 269 return ((map1 == map2) || 270 ((map1 == NULL) && (map2 == kernel_map)) || 271 ((map1 == kernel_map) && (map2 == NULL))); 272 } 273 274 bool 275 db_map_current(struct vm_map *map) 276 { 277 #if 0 278 thread_t thread; 279 280 return ((map == NULL) || 281 (map == kernel_map) || 282 (((thread = current_thread()) != NULL) && 283 (map == thread->task->map))); 284 #else 285 286 return (1); 287 #endif 288 } 289 290 struct vm_map * 291 db_map_addr(vaddr_t addr) 292 { 293 #if 0 294 thread_t thread; 295 296 /* 297 * We want to return kernel_map for all 298 * non-user addresses, even when debugging 299 * kernel tasks with their own maps. 300 */ 301 302 if ((VM_MIN_ADDRESS <= addr) && (addr < VM_MAX_ADDRESS) && 303 ((thread = current_thread()) != NULL)) 304 return thread->task->map; 305 else 306 #endif 307 return kernel_map; 308 } 309