usr/src/boot/sys/boot/common/boot.c

   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
  29 /*
  30  * Loading modules, booting the system
  31  */
  32
  33 #include <stand.h>
  34 #include <string.h>
  35
  36 #include "bootstrap.h"
  37
  38 static char     *getbootfile(int try);
  39 static int      loadakernel(int try, int argc, char *argv[]);
  40
  41 /*
  42  * List of kernel names to try (may be overwritten by boot.config)
  43  * XXX should move from here?
  44  */
  45 static const char *default_bootfiles = "kernel";
  46
  47 static int autoboot_tried;
  48
  49 /*
  50  * The user wants us to boot.
  51  */
  52 COMMAND_SET(boot, "boot", "boot a file or loaded kernel", command_boot);
  53
  54 static int
  55 command_boot(int argc, char *argv[])
  56 {
  57         struct preloaded_file *fp;
  58
  59         /*
  60          * See if the user has specified an explicit kernel to boot.
  61          */
  62         if ((argc > 1) && (argv[1][0] == '/')) {
  63
  64                 /* XXX maybe we should discard everything and start again? */
  65                 if (file_findfile(NULL, NULL) != NULL) {
  66                         snprintf(command_errbuf, sizeof (command_errbuf),
  67                             "can't boot '%s', kernel module already loaded",
  68                             argv[1]);
  69                         return (CMD_ERROR);
  70                 }
  71
  72                 /* find/load the kernel module */
  73                 if (mod_loadkld(argv[1], argc - 2, argv + 2) != 0)
  74                         return (CMD_ERROR);
  75                 /* we have consumed all arguments */
  76                 argc = 1;
  77         }
  78
  79         /*
  80          * See if there is a kernel module already loaded
  81          */
  82         if (file_findfile(NULL, NULL) == NULL)
  83                 if (loadakernel(0, argc - 1, argv + 1)) {
  84                         /* we have consumed all arguments */
  85                         argc = 1;
  86                 }
  87
  88         /*
  89          * Loaded anything yet?
  90          */
  91         if ((fp = file_findfile(NULL, NULL)) == NULL) {
  92                 command_errmsg = "no bootable kernel";
  93                 return (CMD_ERROR);
  94         }
  95
  96         /*
  97          * If we were given arguments, discard any previous.
  98          * XXX should we merge arguments?  Hard to DWIM.
  99          */
 100         if (argc > 1) {
 101                 free(fp->f_args);
 102                 fp->f_args = unargv(argc - 1, argv + 1);
 103         }
 104
 105         /* Hook for platform-specific autoloading of modules */
 106         if (archsw.arch_autoload() != 0)
 107                 return (CMD_ERROR);
 108
 109         /* Call the exec handler from the loader matching the kernel */
 110         file_formats[fp->f_loader]->l_exec(fp);
 111         return (CMD_ERROR);
 112 }
 113
 114
 115 /*
 116  * Autoboot after a delay
 117  */
 118
 119 COMMAND_SET(autoboot, "autoboot", "boot automatically after a delay",
 120     command_autoboot);
 121
 122 static int
 123 command_autoboot(int argc, char *argv[])
 124 {
 125         int howlong;
 126         char *cp, *prompt;
 127
 128         prompt = NULL;
 129         howlong = -1;
 130         switch (argc) {
 131         case 3:
 132                 prompt = argv[2];
 133                 /* FALLTHROUGH */
 134         case 2:
 135                 howlong = strtol(argv[1], &cp, 0);
 136                 if (*cp != 0) {
 137                         snprintf(command_errbuf, sizeof (command_errbuf),
 138                             "bad delay '%s'", argv[1]);
 139                         return (CMD_ERROR);
 140                 }
 141                 /* FALLTHROUGH */
 142         case 1:
 143                 return (autoboot(howlong, prompt));
 144         }
 145
 146         command_errmsg = "too many arguments";
 147         return (CMD_ERROR);
 148 }
 149
 150 /*
 151  * Called before we go interactive.  If we think we can autoboot, and
 152  * we haven't tried already, try now.
 153  */
 154 void
 155 autoboot_maybe(void)
 156 {
 157         char *cp;
 158
 159         /* compatibility with sparc prom, check for autoboot? */
 160         cp = getenv("autoboot?");
 161         if (cp != NULL && strcasecmp(cp, "true") != 0)
 162                 return;
 163         cp = getenv("autoboot_delay");
 164         if ((autoboot_tried == 0) && ((cp == NULL) || strcasecmp(cp, "NO")))
 165                 autoboot(-1, NULL);             /* try to boot automatically */
 166 }
 167
 168 int
 169 autoboot(int timeout, char *prompt)
 170 {
 171         time_t when, otime, ntime;
 172         int c, yes;
 173         char *argv[2], *cp, *ep;
 174         char *kernelname;
 175         struct preloaded_file *fp;
 176
 177         autoboot_tried = 1;
 178
 179         if (timeout == -1) {
 180                 timeout = 10;
 181                 /* try to get a delay from the environment */
 182                 if ((cp = getenv("autoboot_delay"))) {
 183                         timeout = strtol(cp, &ep, 0);
 184                         if (cp == ep)
 185                                 timeout = 10;   /* Unparseable? Set default! */
 186                 }
 187         }
 188
 189         fp = file_findfile(NULL, NULL);
 190         if (fp == NULL) {
 191                 /* no preloaded files, run command start to load all */
 192                 bf_run("start");
 193                 fp = file_findfile(NULL, NULL);
 194                 if (fp == NULL) { /* still nothing? can't boot */
 195                         command_errmsg = "no valid kernel found";
 196                         return (CMD_ERROR);
 197                 }
 198         }
 199
 200         kernelname = fp->f_name;
 201
 202         if (timeout >= 0) {
 203                 otime = time(NULL);
 204                 when = otime + timeout; /* when to boot */
 205
 206                 yes = 0;
 207
 208                 printf("%s\n", (prompt == NULL) ?
 209                     "Hit [Enter] to boot immediately, or any other key "
 210                     "for command prompt." : prompt);
 211
 212                 for (;;) {
 213                         if (ischar()) {
 214                                 c = getchar();
 215                                 if ((c == '\r') || (c == '\n'))
 216                                         yes = 1;
 217                                 break;
 218                         }
 219                         ntime = time(NULL);
 220                         if (ntime >= when) {
 221                                 yes = 1;
 222                                 break;
 223                         }
 224
 225                         if (ntime != otime) {
 226                                 printf("\rBooting [%s] in %d second%s... ",
 227                                     kernelname, (int)(when - ntime),
 228                                     (when - ntime) == 1? "":"s");
 229                                 otime = ntime;
 230                         }
 231                 }
 232         } else {
 233                 yes = 1;
 234         }
 235
 236         if (yes)
 237                 printf("\rBooting [%s]...               ", kernelname);
 238         putchar('\n');
 239         if (yes) {
 240                 argv[0] = "boot";
 241                 argv[1] = NULL;
 242                 return (command_boot(1, argv));
 243         }
 244         return (CMD_OK);
 245 }
 246
 247 /*
 248  * Scrounge for the name of the (try)'th file we will try to boot.
 249  */
 250 static char *
 251 getbootfile(int try)
 252 {
 253         static char *name = NULL;
 254         const char *spec, *ep;
 255         size_t len;
 256
 257         /* we use dynamic storage */
 258         free(name);
 259         name = NULL;
 260
 261         /*
 262          * Try $bootfile, then try our builtin default
 263          */
 264         if ((spec = getenv("bootfile")) == NULL)
 265                 spec = default_bootfiles;
 266
 267         while ((try > 0) && (spec != NULL)) {
 268                 spec = strchr(spec, ';');
 269                 if (spec)
 270                         spec++; /* skip over the leading ';' */
 271                 try--;
 272         }
 273         if (spec != NULL) {
 274                 if ((ep = strchr(spec, ';')) != NULL) {
 275                         len = ep - spec;
 276                 } else {
 277                         len = strlen(spec);
 278                 }
 279                 name = malloc(len + 1);
 280                 strncpy(name, spec, len);
 281                 name[len] = 0;
 282         }
 283         if (name && name[0] == 0) {
 284                 free(name);
 285                 name = NULL;
 286         }
 287         return (name);
 288 }
 289
 290 /*
 291  * Try to find the /etc/fstab file on the filesystem (rootdev),
 292  * which should be be the root filesystem, and parse it to find
 293  * out what the kernel ought to think the root filesystem is.
 294  *
 295  * If we're successful, set vfs.root.mountfrom to <vfstype>:<path>
 296  * so that the kernel can tell both which VFS and which node to use
 297  * to mount the device.  If this variable's already set, don't
 298  * overwrite it.
 299  */
 300 int
 301 getrootmount(char *rootdev)
 302 {
 303         char lbuf[128], *cp, *ep, *dev, *fstyp, *options;
 304         int fd, error;
 305
 306         if (getenv("vfs.root.mountfrom") != NULL)
 307                 return (0);
 308
 309         error = 1;
 310         sprintf(lbuf, "%s/etc/fstab", rootdev);
 311         if ((fd = open(lbuf, O_RDONLY)) < 0)
 312                 goto notfound;
 313
 314         /*
 315          * loop reading lines from /etc/fstab
 316          * What was that about sscanf again?
 317          */
 318         fstyp = NULL;
 319         dev = NULL;
 320         while (fgetstr(lbuf, sizeof (lbuf), fd) >= 0) {
 321                 if ((lbuf[0] == 0) || (lbuf[0] == '#'))
 322                         continue;
 323
 324                 /* skip device name */
 325                 for (cp = lbuf; (*cp != 0) && !isspace(*cp); cp++)
 326                         ;
 327                 if (*cp == 0)           /* misformatted */
 328                         continue;
 329                 /* delimit and save */
 330                 *cp++ = 0;
 331                 free(dev);
 332                 dev = strdup(lbuf);
 333
 334                 /* skip whitespace up to mountpoint */
 335                 while ((*cp != 0) && isspace(*cp))
 336                         cp++;
 337                 /* must have /<space> to be root */
 338                 if ((*cp == 0) || (*cp != '/') || !isspace(*(cp + 1)))
 339                         continue;
 340                 /* skip whitespace up to fstype */
 341                 cp += 2;
 342                 while ((*cp != 0) && isspace(*cp))
 343                         cp++;
 344                 if (*cp == 0)           /* misformatted */
 345                         continue;
 346                 /* skip text to end of fstype and delimit */
 347                 ep = cp;
 348                 while ((*cp != 0) && !isspace(*cp))
 349                         cp++;
 350                 *cp = 0;
 351                 free(fstyp);
 352                 fstyp = strdup(ep);
 353
 354                 /* skip whitespace up to mount options */
 355                 cp += 1;
 356                 while ((*cp != 0) && isspace(*cp))
 357                         cp++;
 358                 if (*cp == 0)           /* misformatted */
 359                         continue;
 360                 /* skip text to end of mount options and delimit */
 361                 ep = cp;
 362                 while ((*cp != 0) && !isspace(*cp))
 363                         cp++;
 364                 *cp = 0;
 365                 options = strdup(ep);
 366                 /*
 367                  * Build the <fstype>:<device> and save it in
 368                  * vfs.root.mountfrom
 369                  */
 370                 sprintf(lbuf, "%s:%s", fstyp, dev);
 371                 setenv("vfs.root.mountfrom", lbuf, 0);
 372
 373                 /*
 374                  * Don't override vfs.root.mountfrom.options if it is
 375                  * already set
 376                  */
 377                 if (getenv("vfs.root.mountfrom.options") == NULL) {
 378                         /* save mount options */
 379                         setenv("vfs.root.mountfrom.options", options, 0);
 380                 }
 381                 free(options);
 382                 error = 0;
 383                 break;
 384         }
 385         close(fd);
 386         free(dev);
 387         free(fstyp);
 388
 389 notfound:
 390         if (error) {
 391                 const char *currdev;
 392
 393                 currdev = getenv("currdev");
 394                 if (currdev != NULL && strncmp("zfs:", currdev, 4) == 0) {
 395                         cp = strdup(currdev);
 396                         cp[strlen(cp) - 1] = '\0';
 397                         setenv("vfs.root.mountfrom", cp, 0);
 398                         error = 0;
 399                         free(cp);
 400                 }
 401         }
 402
 403         return (error);
 404 }
 405
 406 static int
 407 loadakernel(int try, int argc, char *argv[])
 408 {
 409         char *cp;
 410
 411         for (try = 0; (cp = getbootfile(try)) != NULL; try++)
 412                 if (mod_loadkld(cp, argc - 1, argv + 1) != 0)
 413                         printf("can't load '%s'\n", cp);
 414                 else
 415                         return (1);
 416         return (0);
 417 }