1 /*- 2 * Copyright (c) 1998 Michael Smith 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/kern/subr_module.c,v 1.6 1999/10/11 15:19:10 peter Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/linker.h> 32 33 /* 34 * Preloaded module support 35 */ 36 37 caddr_t preload_metadata; 38 39 /* 40 * Search for the preloaded module (name) 41 */ 42 caddr_t 43 preload_search_by_name(const char *name) 44 { 45 caddr_t curp; 46 u_int32_t *hdr; 47 int next; 48 49 if (preload_metadata != NULL) { 50 51 curp = preload_metadata; 52 for (;;) { 53 hdr = (u_int32_t *)curp; 54 if (hdr[0] == 0 && hdr[1] == 0) 55 break; 56 57 /* Search for a MODINFO_NAME field */ 58 if ((hdr[0] == MODINFO_NAME) && 59 !strcmp(name, curp + sizeof(u_int32_t) * 2)) 60 return(curp); 61 62 /* skip to next field */ 63 next = sizeof(u_int32_t) * 2 + hdr[1]; 64 next = roundup(next, sizeof(u_long)); 65 curp += next; 66 } 67 } 68 return(NULL); 69 } 70 71 /* 72 * Search for the first preloaded module of (type) 73 */ 74 caddr_t 75 preload_search_by_type(const char *type) 76 { 77 caddr_t curp, lname; 78 u_int32_t *hdr; 79 int next; 80 81 if (preload_metadata != NULL) { 82 83 curp = preload_metadata; 84 lname = NULL; 85 for (;;) { 86 hdr = (u_int32_t *)curp; 87 if (hdr[0] == 0 && hdr[1] == 0) 88 break; 89 90 /* remember the start of each record */ 91 if (hdr[0] == MODINFO_NAME) 92 lname = curp; 93 94 /* Search for a MODINFO_TYPE field */ 95 if ((hdr[0] == MODINFO_TYPE) && 96 !strcmp(type, curp + sizeof(u_int32_t) * 2)) 97 return(lname); 98 99 /* skip to next field */ 100 next = sizeof(u_int32_t) * 2 + hdr[1]; 101 next = roundup(next, sizeof(u_long)); 102 curp += next; 103 } 104 } 105 return(NULL); 106 } 107 108 /* 109 * Walk through the preloaded module list 110 */ 111 caddr_t 112 preload_search_next_name(caddr_t base) 113 { 114 caddr_t curp; 115 u_int32_t *hdr; 116 int next; 117 118 if (preload_metadata != NULL) { 119 120 /* Pick up where we left off last time */ 121 if (base) { 122 /* skip to next field */ 123 curp = base; 124 hdr = (u_int32_t *)curp; 125 next = sizeof(u_int32_t) * 2 + hdr[1]; 126 next = roundup(next, sizeof(u_long)); 127 curp += next; 128 } else 129 curp = preload_metadata; 130 131 for (;;) { 132 hdr = (u_int32_t *)curp; 133 if (hdr[0] == 0 && hdr[1] == 0) 134 break; 135 136 /* Found a new record? */ 137 if (hdr[0] == MODINFO_NAME) 138 return curp; 139 140 /* skip to next field */ 141 next = sizeof(u_int32_t) * 2 + hdr[1]; 142 next = roundup(next, sizeof(u_long)); 143 curp += next; 144 } 145 } 146 return(NULL); 147 } 148 149 /* 150 * Given a preloaded module handle (mod), return a pointer 151 * to the data for the attribute (inf). 152 */ 153 caddr_t 154 preload_search_info(caddr_t mod, int inf) 155 { 156 caddr_t curp; 157 u_int32_t *hdr; 158 u_int32_t type = 0; 159 int next; 160 161 curp = mod; 162 for (;;) { 163 hdr = (u_int32_t *)curp; 164 /* end of module data? */ 165 if (hdr[0] == 0 && hdr[1] == 0) 166 break; 167 /* 168 * We give up once we've looped back to what we were looking at 169 * first - this should normally be a MODINFO_NAME field. 170 */ 171 if (type == 0) { 172 type = hdr[0]; 173 } else { 174 if (hdr[0] == type) 175 break; 176 } 177 178 /* 179 * Attribute match? Return pointer to data. 180 * Consumer may safely assume that size value preceeds 181 * data. 182 */ 183 if (hdr[0] == inf) 184 return(curp + (sizeof(u_int32_t) * 2)); 185 186 /* skip to next field */ 187 next = sizeof(u_int32_t) * 2 + hdr[1]; 188 next = roundup(next, sizeof(u_long)); 189 curp += next; 190 } 191 return(NULL); 192 } 193 194 /* 195 * Delete a preload record by name. 196 */ 197 void 198 preload_delete_name(const char *name) 199 { 200 caddr_t curp; 201 u_int32_t *hdr; 202 int next; 203 int clearing; 204 205 if (preload_metadata != NULL) { 206 207 clearing = 0; 208 curp = preload_metadata; 209 for (;;) { 210 hdr = (u_int32_t *)curp; 211 if (hdr[0] == 0 && hdr[1] == 0) 212 break; 213 214 /* Search for a MODINFO_NAME field */ 215 if (hdr[0] == MODINFO_NAME) { 216 if (!strcmp(name, curp + sizeof(u_int32_t) * 2)) 217 clearing = 1; /* got it, start clearing */ 218 else if (clearing) 219 clearing = 0; /* at next one now.. better stop */ 220 } 221 if (clearing) 222 hdr[0] = MODINFO_EMPTY; 223 224 /* skip to next field */ 225 next = sizeof(u_int32_t) * 2 + hdr[1]; 226 next = roundup(next, sizeof(u_long)); 227 curp += next; 228 } 229 } 230 } 231 232 /* Called from locore on i386. Convert physical pointers to kvm. Sigh. */ 233 void 234 preload_bootstrap_relocate(vm_offset_t offset) 235 { 236 caddr_t curp; 237 u_int32_t *hdr; 238 vm_offset_t *ptr; 239 int next; 240 241 if (preload_metadata != NULL) { 242 243 curp = preload_metadata; 244 for (;;) { 245 hdr = (u_int32_t *)curp; 246 if (hdr[0] == 0 && hdr[1] == 0) 247 break; 248 249 /* Deal with the ones that we know we have to fix */ 250 switch (hdr[0]) { 251 case MODINFO_ADDR: 252 case MODINFO_METADATA|MODINFOMD_SSYM: 253 case MODINFO_METADATA|MODINFOMD_ESYM: 254 ptr = (vm_offset_t *)(curp + (sizeof(u_int32_t) * 2)); 255 *ptr += offset; 256 break; 257 } 258 /* The rest is beyond us for now */ 259 260 /* skip to next field */ 261 next = sizeof(u_int32_t) * 2 + hdr[1]; 262 next = roundup(next, sizeof(u_long)); 263 curp += next; 264 } 265 } 266 } 267