boot.c revision 193192
1/*- 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 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 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/boot/common/boot.c 193192 2009-06-01 01:02:30Z rodrigc $"); 29 30/* 31 * Loading modules, booting the system 32 */ 33 34#include <stand.h> 35#include <string.h> 36 37#include "bootstrap.h" 38 39static char *getbootfile(int try); 40static int loadakernel(int try, int argc, char* argv[]); 41 42/* List of kernel names to try (may be overwritten by boot.config) XXX should move from here? */ 43static const char *default_bootfiles = "kernel"; 44 45static int autoboot_tried; 46 47/* 48 * The user wants us to boot. 49 */ 50COMMAND_SET(boot, "boot", "boot a file or loaded kernel", command_boot); 51 52static int 53command_boot(int argc, char *argv[]) 54{ 55 struct preloaded_file *fp; 56 57 /* 58 * See if the user has specified an explicit kernel to boot. 59 */ 60 if ((argc > 1) && (argv[1][0] != '-')) { 61 62 /* XXX maybe we should discard everything and start again? */ 63 if (file_findfile(NULL, NULL) != NULL) { 64 sprintf(command_errbuf, "can't boot '%s', kernel module already loaded", argv[1]); 65 return(CMD_ERROR); 66 } 67 68 /* find/load the kernel module */ 69 if (mod_loadkld(argv[1], argc - 2, argv + 2) != 0) 70 return(CMD_ERROR); 71 /* we have consumed all arguments */ 72 argc = 1; 73 } 74 75 /* 76 * See if there is a kernel module already loaded 77 */ 78 if (file_findfile(NULL, NULL) == NULL) 79 if (loadakernel(0, argc - 1, argv + 1)) 80 /* we have consumed all arguments */ 81 argc = 1; 82 83 /* 84 * Loaded anything yet? 85 */ 86 if ((fp = file_findfile(NULL, NULL)) == NULL) { 87 command_errmsg = "no bootable kernel"; 88 return(CMD_ERROR); 89 } 90 91 /* 92 * If we were given arguments, discard any previous. 93 * XXX should we merge arguments? Hard to DWIM. 94 */ 95 if (argc > 1) { 96 if (fp->f_args != NULL) 97 free(fp->f_args); 98 fp->f_args = unargv(argc - 1, argv + 1); 99 } 100 101 /* Hook for platform-specific autoloading of modules */ 102 if (archsw.arch_autoload() != 0) 103 return(CMD_ERROR); 104 105 /* Call the exec handler from the loader matching the kernel */ 106 file_formats[fp->f_loader]->l_exec(fp); 107 return(CMD_ERROR); 108} 109 110 111/* 112 * Autoboot after a delay 113 */ 114 115COMMAND_SET(autoboot, "autoboot", "boot automatically after a delay", command_autoboot); 116 117static int 118command_autoboot(int argc, char *argv[]) 119{ 120 int howlong; 121 char *cp, *prompt; 122 123 prompt = NULL; 124 howlong = -1; 125 switch(argc) { 126 case 3: 127 prompt = argv[2]; 128 /* FALLTHROUGH */ 129 case 2: 130 howlong = strtol(argv[1], &cp, 0); 131 if (*cp != 0) { 132 sprintf(command_errbuf, "bad delay '%s'", argv[1]); 133 return(CMD_ERROR); 134 } 135 /* FALLTHROUGH */ 136 case 1: 137 return(autoboot(howlong, prompt)); 138 } 139 140 command_errmsg = "too many arguments"; 141 return(CMD_ERROR); 142} 143 144/* 145 * Called before we go interactive. If we think we can autoboot, and 146 * we haven't tried already, try now. 147 */ 148void 149autoboot_maybe() 150{ 151 char *cp; 152 153 cp = getenv("autoboot_delay"); 154 if ((autoboot_tried == 0) && ((cp == NULL) || strcasecmp(cp, "NO"))) 155 autoboot(-1, NULL); /* try to boot automatically */ 156} 157 158int 159autoboot(int timeout, char *prompt) 160{ 161 time_t when, otime, ntime; 162 int c, yes; 163 char *argv[2], *cp, *ep; 164 char *kernelname; 165 166 autoboot_tried = 1; 167 168 if (timeout == -1) { 169 timeout = 10; 170 /* try to get a delay from the environment */ 171 if ((cp = getenv("autoboot_delay"))) { 172 timeout = strtol(cp, &ep, 0); 173 if (cp == ep) 174 timeout = 10; /* Unparseable? Set default! */ 175 } 176 } 177 178 kernelname = getenv("kernelname"); 179 if (kernelname == NULL) { 180 argv[0] = NULL; 181 loadakernel(0, 0, argv); 182 kernelname = getenv("kernelname"); 183 if (kernelname == NULL) { 184 command_errmsg = "no valid kernel found"; 185 return(CMD_ERROR); 186 } 187 } 188 189 if (timeout >= 0) { 190 otime = time(NULL); 191 when = otime + timeout; /* when to boot */ 192 193 yes = 0; 194 195 printf("%s\n", (prompt == NULL) ? "Hit [Enter] to boot immediately, or any other key for command prompt." : prompt); 196 197 for (;;) { 198 if (ischar()) { 199 c = getchar(); 200 if ((c == '\r') || (c == '\n')) 201 yes = 1; 202 break; 203 } 204 ntime = time(NULL); 205 if (ntime >= when) { 206 yes = 1; 207 break; 208 } 209 210 if (ntime != otime) { 211 printf("\rBooting [%s] in %d second%s... ", 212 kernelname, (int)(when - ntime), 213 (when-ntime)==1?"":"s"); 214 otime = ntime; 215 } 216 } 217 } else { 218 yes = 1; 219 } 220 221 if (yes) 222 printf("\rBooting [%s]... ", kernelname); 223 putchar('\n'); 224 if (yes) { 225 argv[0] = "boot"; 226 argv[1] = NULL; 227 return(command_boot(1, argv)); 228 } 229 return(CMD_OK); 230} 231 232/* 233 * Scrounge for the name of the (try)'th file we will try to boot. 234 */ 235static char * 236getbootfile(int try) 237{ 238 static char *name = NULL; 239 const char *spec, *ep; 240 size_t len; 241 242 /* we use dynamic storage */ 243 if (name != NULL) { 244 free(name); 245 name = NULL; 246 } 247 248 /* 249 * Try $bootfile, then try our builtin default 250 */ 251 if ((spec = getenv("bootfile")) == NULL) 252 spec = default_bootfiles; 253 254 while ((try > 0) && (spec != NULL)) { 255 spec = strchr(spec, ';'); 256 if (spec) 257 spec++; /* skip over the leading ';' */ 258 try--; 259 } 260 if (spec != NULL) { 261 if ((ep = strchr(spec, ';')) != NULL) { 262 len = ep - spec; 263 } else { 264 len = strlen(spec); 265 } 266 name = malloc(len + 1); 267 strncpy(name, spec, len); 268 name[len] = 0; 269 } 270 if (name && name[0] == 0) { 271 free(name); 272 name = NULL; 273 } 274 return(name); 275} 276 277/* 278 * Try to find the /etc/fstab file on the filesystem (rootdev), 279 * which should be be the root filesystem, and parse it to find 280 * out what the kernel ought to think the root filesystem is. 281 * 282 * If we're successful, set vfs.root.mountfrom to <vfstype>:<path> 283 * so that the kernel can tell both which VFS and which node to use 284 * to mount the device. If this variable's already set, don't 285 * overwrite it. 286 */ 287int 288getrootmount(char *rootdev) 289{ 290 char lbuf[128], *cp, *ep, *dev, *fstyp, *options; 291 int fd, error; 292 293 if (getenv("vfs.root.mountfrom") != NULL) 294 return(0); 295 296 sprintf(lbuf, "%s/etc/fstab", rootdev); 297 if ((fd = open(lbuf, O_RDONLY)) < 0) 298 return(1); 299 300 /* loop reading lines from /etc/fstab What was that about sscanf again? */ 301 error = 1; 302 while (fgetstr(lbuf, sizeof(lbuf), fd) >= 0) { 303 if ((lbuf[0] == 0) || (lbuf[0] == '#')) 304 continue; 305 306 /* skip device name */ 307 for (cp = lbuf; (*cp != 0) && !isspace(*cp); cp++) 308 ; 309 if (*cp == 0) /* misformatted */ 310 continue; 311 /* delimit and save */ 312 *cp++ = 0; 313 dev = strdup(lbuf); 314 315 /* skip whitespace up to mountpoint */ 316 while ((*cp != 0) && isspace(*cp)) 317 cp++; 318 /* must have /<space> to be root */ 319 if ((*cp == 0) || (*cp != '/') || !isspace(*(cp + 1))) 320 continue; 321 /* skip whitespace up to fstype */ 322 cp += 2; 323 while ((*cp != 0) && isspace(*cp)) 324 cp++; 325 if (*cp == 0) /* misformatted */ 326 continue; 327 /* skip text to end of fstype and delimit */ 328 ep = cp; 329 while ((*cp != 0) && !isspace(*cp)) 330 cp++; 331 *cp = 0; 332 fstyp = strdup(ep); 333 334 /* skip whitespace up to mount options */ 335 cp += 1; 336 while ((*cp != 0) && isspace(*cp)) 337 cp++; 338 if (*cp == 0) /* misformatted */ 339 continue; 340 /* skip text to end of mount options and delimit */ 341 ep = cp; 342 while ((*cp != 0) && !isspace(*cp)) 343 cp++; 344 *cp = 0; 345 options = strdup(ep); 346 /* Build the <fstype>:<device> and save it in vfs.root.mountfrom */ 347 sprintf(lbuf, "%s:%s", fstyp, dev); 348 free(dev); 349 free(fstyp); 350 setenv("vfs.root.mountfrom", lbuf, 0); 351 352 /* Don't override vfs.root.mountfrom.options if it is already set */ 353 if (getenv("vfs.root.mountfrom.options") == NULL) { 354 /* save mount options */ 355 setenv("vfs.root.mountfrom.options", options, 0); 356 } 357 free(options); 358 error = 0; 359 break; 360 } 361 close(fd); 362 return(error); 363} 364 365static int 366loadakernel(int try, int argc, char* argv[]) 367{ 368 char *cp; 369 370 for (try = 0; (cp = getbootfile(try)) != NULL; try++) 371 if (mod_loadkld(cp, argc - 1, argv + 1) != 0) 372 printf("can't load '%s'\n", cp); 373 else 374 return 1; 375 return 0; 376} 377