1 /* $OpenBSD: db_watch.c,v 1.18 2020/10/15 03:14:00 deraadt Exp $ */ 2 /* $NetBSD: db_watch.c,v 1.9 1996/03/30 22:30:12 christos Exp $ */ 3 4 /* 5 * Mach Operating System 6 * Copyright (c) 1993,1992,1991,1990 Carnegie Mellon University 7 * All Rights Reserved. 8 * 9 * Permission to use, copy, modify and distribute this software and its 10 * documentation is hereby granted, provided that both the copyright 11 * notice and this permission notice appear in all copies of the 12 * software, derivative works or modified versions, and any portions 13 * thereof, and that both notices appear in supporting documentation. 14 * 15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 16 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 17 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 18 * 19 * Carnegie Mellon requests users of this software to return to 20 * 21 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 22 * School of Computer Science 23 * Carnegie Mellon University 24 * Pittsburgh PA 15213-3890 25 * 26 * any improvements or extensions that they make and grant Carnegie Mellon 27 * the rights to redistribute these changes. 28 * 29 * Author: Richard P. Draves, Carnegie Mellon University 30 * Date: 10/90 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 36 #include <machine/db_machdep.h> 37 38 #include <ddb/db_break.h> 39 #include <ddb/db_watch.h> 40 #include <ddb/db_lex.h> 41 #include <ddb/db_run.h> 42 #include <ddb/db_sym.h> 43 #include <ddb/db_output.h> 44 #include <ddb/db_command.h> 45 #include <ddb/db_extern.h> 46 47 /* 48 * Watchpoints. 49 */ 50 51 int db_watchpoints_inserted = 1; 52 53 #define NWATCHPOINTS 100 54 struct db_watchpoint db_watch_table[NWATCHPOINTS]; 55 db_watchpoint_t db_next_free_watchpoint = &db_watch_table[0]; 56 db_watchpoint_t db_free_watchpoints = 0; 57 db_watchpoint_t db_watchpoint_list = 0; 58 59 db_watchpoint_t 60 db_watchpoint_alloc(void) 61 { 62 db_watchpoint_t watch; 63 64 if ((watch = db_free_watchpoints) != 0) { 65 db_free_watchpoints = watch->link; 66 return (watch); 67 } 68 if (db_next_free_watchpoint == &db_watch_table[NWATCHPOINTS]) { 69 db_printf("All watchpoints used.\n"); 70 return (0); 71 } 72 watch = db_next_free_watchpoint; 73 db_next_free_watchpoint++; 74 75 return (watch); 76 } 77 78 void 79 db_watchpoint_free(db_watchpoint_t watch) 80 { 81 watch->link = db_free_watchpoints; 82 db_free_watchpoints = watch; 83 } 84 85 void 86 db_set_watchpoint(vaddr_t addr, vsize_t size) 87 { 88 db_watchpoint_t watch; 89 90 /* 91 * Should we do anything fancy with overlapping regions? 92 */ 93 94 for (watch = db_watchpoint_list; watch != 0; watch = watch->link) 95 if (watch->loaddr == addr && watch->hiaddr == addr + size) { 96 db_printf("Already set.\n"); 97 return; 98 } 99 100 watch = db_watchpoint_alloc(); 101 if (watch == 0) { 102 db_printf("Too many watchpoints.\n"); 103 return; 104 } 105 106 watch->loaddr = addr; 107 watch->hiaddr = addr+size; 108 109 watch->link = db_watchpoint_list; 110 db_watchpoint_list = watch; 111 112 db_watchpoints_inserted = 0; 113 } 114 115 void 116 db_delete_watchpoint(vaddr_t addr) 117 { 118 db_watchpoint_t watch; 119 db_watchpoint_t *prev; 120 121 for (prev = &db_watchpoint_list; (watch = *prev) != 0; 122 prev = &watch->link) 123 if (watch->loaddr <= addr && addr < watch->hiaddr) { 124 *prev = watch->link; 125 db_watchpoint_free(watch); 126 return; 127 } 128 129 db_printf("Not set.\n"); 130 } 131 132 void 133 db_list_watchpoints(void) 134 { 135 db_watchpoint_t watch; 136 137 if (db_watchpoint_list == 0) { 138 db_printf("No watchpoints set\n"); 139 return; 140 } 141 142 db_printf(" Address Size\n"); 143 for (watch = db_watchpoint_list; watch != 0; watch = watch->link) 144 db_printf("%8lx %lx\n", 145 watch->loaddr, watch->hiaddr - watch->loaddr); 146 } 147 148 /* Delete watchpoint */ 149 /*ARGSUSED*/ 150 void 151 db_deletewatch_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif) 152 { 153 db_delete_watchpoint(addr); 154 } 155 156 /* Set watchpoint */ 157 /*ARGSUSED*/ 158 void 159 db_watchpoint_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif) 160 { 161 vsize_t size; 162 db_expr_t value; 163 164 if (db_expression(&value)) 165 size = (vsize_t) value; 166 else 167 size = 4; 168 db_skip_to_eol(); 169 170 db_set_watchpoint(addr, size); 171 } 172 173 /* list watchpoints */ 174 /*ARGSUSED*/ 175 void 176 db_listwatch_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif) 177 { 178 db_list_watchpoints(); 179 } 180 181 void 182 db_set_watchpoints(void) 183 { 184 db_watchpoint_t watch; 185 186 if (!db_watchpoints_inserted && db_watchpoint_list != NULL) { 187 for (watch = db_watchpoint_list; watch != 0; 188 watch = watch->link) 189 pmap_protect(pmap_kernel(), trunc_page(watch->loaddr), 190 round_page(watch->hiaddr), PROT_READ); 191 pmap_update(pmap_kernel()); 192 db_watchpoints_inserted = 1; 193 } 194 } 195 196 void 197 db_clear_watchpoints(void) 198 { 199 db_watchpoints_inserted = 0; 200 } 201