sys/boot/common/module.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  * $FreeBSD: src/sys/boot/common/module.c,v 1.25 2003/08/25 23:30:41 obrien Exp $
  27  * $DragonFly: src/sys/boot/common/module.c,v 1.4 2004/12/20 13:13:19 joerg Exp $
  28  */
  29
  30 /*
  31  * file/module function dispatcher, support, etc.
  32  */
  33
  34 #include <stand.h>
  35 #include <string.h>
  36 #include <sys/param.h>
  37 #include <sys/linker.h>
  38 #include <sys/module.h>
  39 #include <sys/queue.h>
  40
  41 #include "bootstrap.h"
  42
  43 #define MDIR_REMOVED    0x0001
  44 #define MDIR_NOHINTS    0x0002
  45
  46 struct moduledir {
  47         char    *d_path;        /* path of modules directory */
  48         u_char  *d_hints;       /* content of linker.hints file */
  49         int     d_hintsz;       /* size of hints data */
  50         int     d_flags;
  51         STAILQ_ENTRY(moduledir) d_link;
  52 };
  53
  54 static int                      file_load(char *filename, vm_offset_t dest, struct preloaded_file **result);
  55 static int                      file_loadraw(char *type, char *name);
  56 static int                      file_load_dependencies(struct preloaded_file *base_mod);
  57 static char *                   file_search(const char *name, char **extlist);
  58 static struct kernel_module *   file_findmodule(struct preloaded_file *fp, char *modname, struct mod_depend *verinfo);
  59 static int                      file_havepath(const char *name);
  60 static char                     *mod_searchmodule(char *name, struct mod_depend *verinfo);
  61 static void                     file_insert_tail(struct preloaded_file *mp);
  62 struct file_metadata*           metadata_next(struct file_metadata *base_mp, int type);
  63 static void                     moduledir_readhints(struct moduledir *mdp);
  64 static void                     moduledir_rebuild(void);
  65
  66 /* load address should be tweaked by first module loaded (kernel) */
  67 static vm_offset_t      loadaddr = 0;
  68
  69 static const char       *default_searchpath ="/;/boot;/modules";
  70
  71 static STAILQ_HEAD(, moduledir) moduledir_list = STAILQ_HEAD_INITIALIZER(moduledir_list);
  72
  73 struct preloaded_file *preloaded_files = NULL;
  74
  75 static char *kld_ext_list[] = {
  76     ".ko",
  77     "",
  78     NULL
  79 };
  80
  81
  82 /*
  83  * load an object, either a disk file or code module.
  84  *
  85  * To load a file, the syntax is:
  86  *
  87  * load -t <type> <path>
  88  *
  89  * code modules are loaded as:
  90  *
  91  * load <path> <options>
  92  */
  93
  94 COMMAND_SET(load, "load", "load a kernel or module", command_load);
  95
  96 static int
  97 command_load(int argc, char *argv[])
  98 {
  99     char        *typestr;
 100     int         dofile, dokld, ch, error;
 101
 102     dokld = dofile = 0;
 103     optind = 1;
 104     optreset = 1;
 105     typestr = NULL;
 106     if (argc == 1) {
 107         command_errmsg = "no filename specified";
 108         return(CMD_ERROR);
 109     }
 110     while ((ch = getopt(argc, argv, "kt:")) != -1) {
 111         switch(ch) {
 112         case 'k':
 113             dokld = 1;
 114             break;
 115         case 't':
 116             typestr = optarg;
 117             dofile = 1;
 118             break;
 119         case '?':
 120         default:
 121             /* getopt has already reported an error */
 122             return(CMD_OK);
 123         }
 124     }
 125     argv += (optind - 1);
 126     argc -= (optind - 1);
 127
 128     /*
 129      * Request to load a raw file?
 130      */
 131     if (dofile) {
 132         if ((argc != 2) || (typestr == NULL) || (*typestr == 0)) {
 133             command_errmsg = "invalid load type";
 134             return(CMD_ERROR);
 135         }
 136         return(file_loadraw(typestr, argv[1]));
 137     }
 138     /*
 139      * Do we have explicit KLD load ?
 140      */
 141     if (dokld || file_havepath(argv[1])) {
 142         error = mod_loadkld(argv[1], argc - 2, argv + 2);
 143         if (error == EEXIST)
 144             sprintf(command_errbuf, "warning: KLD '%s' already loaded", argv[1]);
 145         return (error == 0 ? CMD_OK : CMD_ERROR);
 146     }
 147     /*
 148      * Looks like a request for a module.
 149      */
 150     error = mod_load(argv[1], NULL, argc - 2, argv + 2);
 151     if (error == EEXIST)
 152         sprintf(command_errbuf, "warning: module '%s' already loaded", argv[1]);
 153     return (error == 0 ? CMD_OK : CMD_ERROR);
 154 }
 155
 156 COMMAND_SET(unload, "unload", "unload all modules", command_unload);
 157
 158 static int
 159 command_unload(int argc, char *argv[])
 160 {
 161     struct preloaded_file       *fp;
 162
 163     while (preloaded_files != NULL) {
 164         fp = preloaded_files;
 165         preloaded_files = preloaded_files->f_next;
 166         file_discard(fp);
 167     }
 168     loadaddr = 0;
 169     unsetenv("kernelname");
 170     return(CMD_OK);
 171 }
 172
 173 COMMAND_SET(lsmod, "lsmod", "list loaded modules", command_lsmod);
 174
 175 static int
 176 command_lsmod(int argc, char *argv[])
 177 {
 178     struct preloaded_file       *fp;
 179     struct kernel_module        *mp;
 180     struct file_metadata        *md;
 181     char                        lbuf[80];
 182     int                         ch, verbose;
 183
 184     verbose = 0;
 185     optind = 1;
 186     optreset = 1;
 187     while ((ch = getopt(argc, argv, "v")) != -1) {
 188         switch(ch) {
 189         case 'v':
 190             verbose = 1;
 191             break;
 192         case '?':
 193         default:
 194             /* getopt has already reported an error */
 195             return(CMD_OK);
 196         }
 197     }
 198
 199     pager_open();
 200     for (fp = preloaded_files; fp; fp = fp->f_next) {
 201         sprintf(lbuf, " %p: %s (%s, 0x%lx)\n",
 202                 (void *) fp->f_addr, fp->f_name, fp->f_type, (long) fp->f_size);
 203         pager_output(lbuf);
 204         if (fp->f_args != NULL) {
 205             pager_output("    args: ");
 206             pager_output(fp->f_args);
 207             pager_output("\n");
 208         }
 209         if (fp->f_modules) {
 210             pager_output("  modules: ");
 211             for (mp = fp->f_modules; mp; mp = mp->m_next) {
 212                 sprintf(lbuf, "%s.%d ", mp->m_name, mp->m_version);
 213                 pager_output(lbuf);
 214             }
 215             pager_output("\n");
 216         }
 217         if (verbose) {
 218             /* XXX could add some formatting smarts here to display some better */
 219             for (md = fp->f_metadata; md != NULL; md = md->md_next) {
 220                 sprintf(lbuf, "      0x%04x, 0x%lx\n", md->md_type, (long) md->md_size);
 221                 pager_output(lbuf);
 222             }
 223         }
 224     }
 225     pager_close();
 226     return(CMD_OK);
 227 }
 228
 229 /*
 230  * File level interface, functions file_*
 231  */
 232 int
 233 file_load(char *filename, vm_offset_t dest, struct preloaded_file **result)
 234 {
 235     struct preloaded_file *fp;
 236     int error;
 237     int i;
 238
 239     error = EFTYPE;
 240     for (i = 0, fp = NULL; file_formats[i] && fp == NULL; i++) {
 241         error = (file_formats[i]->l_load)(filename, loadaddr, &fp);
 242         if (error == 0) {
 243             fp->f_loader = i;           /* remember the loader */
 244             *result = fp;
 245             break;
 246         }
 247         if (error == EFTYPE)
 248             continue;           /* Unknown to this handler? */
 249         if (error) {
 250             sprintf(command_errbuf, "can't load file '%s': %s",
 251                 filename, strerror(error));
 252             break;
 253         }
 254     }
 255     return (error);
 256 }
 257
 258 static int
 259 file_load_dependencies(struct preloaded_file *base_file) {
 260     struct file_metadata *md;
 261     struct preloaded_file *fp;
 262     struct mod_depend *verinfo;
 263     struct kernel_module *mp;
 264     char *dmodname;
 265     int error;
 266
 267     md = file_findmetadata(base_file, MODINFOMD_DEPLIST);
 268     if (md == NULL)
 269         return (0);
 270     error = 0;
 271     do {
 272         verinfo = (struct mod_depend*)md->md_data;
 273         dmodname = (char *)(verinfo + 1);
 274         if (file_findmodule(NULL, dmodname, verinfo) == NULL) {
 275             printf("loading required module '%s'\n", dmodname);
 276             error = mod_load(dmodname, verinfo, 0, NULL);
 277             if (error)
 278                 break;
 279             /*
 280              * If module loaded via kld name which isn't listed
 281              * in the linker.hints file, we should check if it have
 282              * required version.
 283              */
 284             mp = file_findmodule(NULL, dmodname, verinfo);
 285             if (mp == NULL) {
 286                 sprintf(command_errbuf, "module '%s' exists but with wrong version",
 287                     dmodname);
 288                 error = ENOENT;
 289                 break;
 290             }
 291         }
 292         md = metadata_next(md, MODINFOMD_DEPLIST);
 293     } while (md);
 294     if (!error)
 295         return (0);
 296     /* Load failed; discard everything */
 297     while (base_file != NULL) {
 298         fp = base_file;
 299         base_file = base_file->f_next;
 300         file_discard(fp);
 301     }
 302     return (error);
 303 }
 304 /*
 305  * We've been asked to load (name) as (type), so just suck it in,
 306  * no arguments or anything.
 307  */
 308 int
 309 file_loadraw(char *type, char *name)
 310 {
 311     struct preloaded_file       *fp;
 312     char                        *cp;
 313     int                         fd, got;
 314     vm_offset_t                 laddr;
 315
 316     /* We can't load first */
 317     if ((file_findfile(NULL, NULL)) == NULL) {
 318         command_errmsg = "can't load file before kernel";
 319         return(CMD_ERROR);
 320     }
 321
 322     /* locate the file on the load path */
 323     cp = file_search(name, NULL);
 324     if (cp == NULL) {
 325         sprintf(command_errbuf, "can't find '%s'", name);
 326         return(CMD_ERROR);
 327     }
 328     name = cp;
 329
 330     if ((fd = open(name, O_RDONLY)) < 0) {
 331         sprintf(command_errbuf, "can't open '%s': %s", name, strerror(errno));
 332         free(name);
 333         return(CMD_ERROR);
 334     }
 335
 336     laddr = loadaddr;
 337     for (;;) {
 338         /* read in 4k chunks; size is not really important */
 339         got = archsw.arch_readin(fd, laddr, 4096);
 340         if (got == 0)                           /* end of file */
 341             break;
 342         if (got < 0) {                          /* error */
 343             sprintf(command_errbuf, "error reading '%s': %s", name, strerror(errno));
 344             free(name);
 345             close(fd);
 346             return(CMD_ERROR);
 347         }
 348         laddr += got;
 349     }
 350
 351     /* Looks OK so far; create & populate control structure */
 352     fp = file_alloc();
 353     fp->f_name = name;
 354     fp->f_type = strdup(type);
 355     fp->f_args = NULL;
 356     fp->f_metadata = NULL;
 357     fp->f_loader = -1;
 358     fp->f_addr = loadaddr;
 359     fp->f_size = laddr - loadaddr;
 360
 361     /* recognise space consumption */
 362     loadaddr = laddr;
 363
 364     /* Add to the list of loaded files */
 365     file_insert_tail(fp);
 366     close(fd);
 367     return(CMD_OK);
 368 }
 369
 370 /*
 371  * Load the module (name), pass it (argc),(argv), add container file
 372  * to the list of loaded files.
 373  * If module is already loaded just assign new argc/argv.
 374  */
 375 int
 376 mod_load(char *modname, struct mod_depend *verinfo, int argc, char *argv[])
 377 {
 378     struct kernel_module        *mp;
 379     int                         err;
 380     char                        *filename;
 381
 382     if (file_havepath(modname)) {
 383         printf("Warning: mod_load() called instead of mod_loadkld() for module '%s'\n", modname);
 384         return (mod_loadkld(modname, argc, argv));
 385     }
 386     /* see if module is already loaded */
 387     mp = file_findmodule(NULL, modname, verinfo);
 388     if (mp) {
 389 #ifdef moduleargs
 390         if (mp->m_args)
 391             free(mp->m_args);
 392         mp->m_args = unargv(argc, argv);
 393 #endif
 394         sprintf(command_errbuf, "warning: module '%s' already loaded", mp->m_name);
 395         return (0);
 396     }
 397     /* locate file with the module on the search path */
 398     filename = mod_searchmodule(modname, verinfo);
 399     if (filename == NULL) {
 400         sprintf(command_errbuf, "can't find '%s'", modname);
 401         return (ENOENT);
 402     }
 403     err = mod_loadkld(filename, argc, argv);
 404     return (err);
 405 }
 406
 407 /*
 408  * Load specified KLD. If path is omitted, then try to locate it via
 409  * search path.
 410  */
 411 int
 412 mod_loadkld(const char *kldname, int argc, char *argv[])
 413 {
 414     struct preloaded_file       *fp, *last_file;
 415     int                         err;
 416     char                        *filename;
 417
 418     /*
 419      * Get fully qualified KLD name
 420      */
 421     filename = file_search(kldname, kld_ext_list);
 422     if (filename == NULL) {
 423         sprintf(command_errbuf, "can't find '%s'", kldname);
 424         return (ENOENT);
 425     }
 426     /*
 427      * Check if KLD already loaded
 428      */
 429     fp = file_findfile(filename, NULL);
 430     if (fp) {
 431         sprintf(command_errbuf, "warning: KLD '%s' already loaded", filename);
 432         free(filename);
 433         return (0);
 434     }
 435     for (last_file = preloaded_files;
 436          last_file != NULL && last_file->f_next != NULL;
 437          last_file = last_file->f_next)
 438         ;
 439
 440     do {
 441         err = file_load(filename, loadaddr, &fp);
 442         if (err)
 443             break;
 444         fp->f_args = unargv(argc, argv);
 445         loadaddr = fp->f_addr + fp->f_size;
 446         file_insert_tail(fp);           /* Add to the list of loaded files */
 447         if (file_load_dependencies(fp) != 0) {
 448             err = ENOENT;
 449             last_file->f_next = NULL;
 450             loadaddr = last_file->f_addr + last_file->f_size;
 451             fp = NULL;
 452             break;
 453         }
 454     } while(0);
 455     if (err == EFTYPE)
 456         sprintf(command_errbuf, "don't know how to load module '%s'", filename);
 457     if (err && fp)
 458         file_discard(fp);
 459     free(filename);
 460     return (err);
 461 }
 462
 463 /*
 464  * Find a file matching (name) and (type).
 465  * NULL may be passed as a wildcard to either.
 466  */
 467 struct preloaded_file *
 468 file_findfile(char *name, char *type)
 469 {
 470     struct preloaded_file *fp;
 471
 472     for (fp = preloaded_files; fp != NULL; fp = fp->f_next) {
 473         if (((name == NULL) || !strcmp(name, fp->f_name)) &&
 474             ((type == NULL) || !strcmp(type, fp->f_type)))
 475             break;
 476     }
 477     return (fp);
 478 }
 479
 480 /*
 481  * Find a module matching (name) inside of given file.
 482  * NULL may be passed as a wildcard.
 483  */
 484 struct kernel_module *
 485 file_findmodule(struct preloaded_file *fp, char *modname,
 486         struct mod_depend *verinfo)
 487 {
 488     struct kernel_module *mp, *best;
 489     int bestver, mver;
 490
 491     if (fp == NULL) {
 492         for (fp = preloaded_files; fp; fp = fp->f_next) {
 493             mp = file_findmodule(fp, modname, verinfo);
 494             if (mp)
 495                 return (mp);
 496         }
 497         return (NULL);
 498     }
 499     best = NULL;
 500     bestver = 0;
 501     for (mp = fp->f_modules; mp; mp = mp->m_next) {
 502         if (strcmp(modname, mp->m_name) == 0) {
 503             if (verinfo == NULL)
 504                 return (mp);
 505             mver = mp->m_version;
 506             if (mver == verinfo->md_ver_preferred)
 507                 return (mp);
 508             if (mver >= verinfo->md_ver_minimum &&
 509                 mver <= verinfo->md_ver_maximum &&
 510                 mver > bestver) {
 511                 best = mp;
 512                 bestver = mver;
 513             }
 514         }
 515     }
 516     return (best);
 517 }
 518 /*
 519  * Make a copy of (size) bytes of data from (p), and associate them as
 520  * metadata of (type) to the module (mp).
 521  */
 522 void
 523 file_addmetadata(struct preloaded_file *fp, int type, size_t size, void *p)
 524 {
 525     struct file_metadata        *md;
 526
 527     md = malloc(sizeof(struct file_metadata) - sizeof(md->md_data) + size);
 528     md->md_size = size;
 529     md->md_type = type;
 530     bcopy(p, md->md_data, size);
 531     md->md_next = fp->f_metadata;
 532     fp->f_metadata = md;
 533 }
 534
 535 /*
 536  * Find a metadata object of (type) associated with the file (fp)
 537  */
 538 struct file_metadata *
 539 file_findmetadata(struct preloaded_file *fp, int type)
 540 {
 541     struct file_metadata *md;
 542
 543     for (md = fp->f_metadata; md != NULL; md = md->md_next)
 544         if (md->md_type == type)
 545             break;
 546     return(md);
 547 }
 548
 549 struct file_metadata *
 550 metadata_next(struct file_metadata *md, int type)
 551 {
 552     if (md == NULL)
 553         return (NULL);
 554     while((md = md->md_next) != NULL)
 555         if (md->md_type == type)
 556             break;
 557     return (md);
 558 }
 559
 560 static char *emptyextlist[] = { "", NULL };
 561
 562 /*
 563  * Check if the given file is in place and return full path to it.
 564  */
 565 static char *
 566 file_lookup(const char *path, const char *name, int namelen, char **extlist)
 567 {
 568     struct stat st;
 569     char        *result, *cp, **cpp;
 570     int         pathlen, extlen, len;
 571
 572     pathlen = strlen(path);
 573     extlen = 0;
 574     if (extlist == NULL)
 575         extlist = emptyextlist;
 576     for (cpp = extlist; *cpp; cpp++) {
 577         len = strlen(*cpp);
 578         if (len > extlen)
 579             extlen = len;
 580     }
 581     result = malloc(pathlen + namelen + extlen + 2);
 582     if (result == NULL)
 583         return (NULL);
 584     bcopy(path, result, pathlen);
 585     if (pathlen > 0 && result[pathlen - 1] != '/')
 586         result[pathlen++] = '/';
 587     cp = result + pathlen;
 588     bcopy(name, cp, namelen);
 589     cp += namelen;
 590     for (cpp = extlist; *cpp; cpp++) {
 591         strcpy(cp, *cpp);
 592         if (stat(result, &st) == 0 && S_ISREG(st.st_mode))
 593             return result;
 594     }
 595     free(result);
 596     return NULL;
 597 }
 598
 599 /*
 600  * Check if file name have any qualifiers
 601  */
 602 static int
 603 file_havepath(const char *name)
 604 {
 605     const char          *cp;
 606
 607     archsw.arch_getdev(NULL, name, &cp);
 608     return (cp != name || strchr(name, '/') != NULL);
 609 }
 610
 611 /*
 612  * Attempt to find the file (name) on the module searchpath.
 613  * If (name) is qualified in any way, we simply check it and
 614  * return it or NULL.  If it is not qualified, then we attempt
 615  * to construct a path using entries in the environment variable
 616  * module_path.
 617  *
 618  * The path we return a pointer to need never be freed, as we manage
 619  * it internally.
 620  */
 621 static char *
 622 file_search(const char *name, char **extlist)
 623 {
 624     struct moduledir    *mdp;
 625     struct stat         sb;
 626     char                *result;
 627     int                 namelen;
 628
 629     /* Don't look for nothing */
 630     if (name == NULL)
 631         return(NULL);
 632
 633     if (*name == 0)
 634         return(strdup(name));
 635
 636     if (file_havepath(name)) {
 637         /* Qualified, so just see if it exists */
 638         if (stat(name, &sb) == 0)
 639             return(strdup(name));
 640         return(NULL);
 641     }
 642     moduledir_rebuild();
 643     result = NULL;
 644     namelen = strlen(name);
 645     STAILQ_FOREACH(mdp, &moduledir_list, d_link) {
 646         result = file_lookup(mdp->d_path, name, namelen, extlist);
 647         if (result)
 648             break;
 649     }
 650     return(result);
 651 }
 652
 653 #define INT_ALIGN(base, ptr)    ptr = \
 654         (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1))
 655
 656 static char *
 657 mod_search_hints(struct moduledir *mdp, const char *modname,
 658         struct mod_depend *verinfo)
 659 {
 660     u_char      *cp, *recptr, *bufend, *best;
 661     char        *result;
 662     int         *intp, bestver, blen, clen, found, ival, modnamelen, reclen;
 663
 664     moduledir_readhints(mdp);
 665     modnamelen = strlen(modname);
 666     found = 0;
 667     result = NULL;
 668     bestver = 0;
 669     if (mdp->d_hints == NULL)
 670         goto bad;
 671     recptr = mdp->d_hints;
 672     bufend = recptr + mdp->d_hintsz;
 673     clen = blen = 0;
 674     best = cp = NULL;
 675     while (recptr < bufend && !found) {
 676         intp = (int*)recptr;
 677         reclen = *intp++;
 678         ival = *intp++;
 679         cp = (char*)intp;
 680         switch (ival) {
 681         case MDT_VERSION:
 682             clen = *cp++;
 683             if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
 684                 break;
 685             cp += clen;
 686             INT_ALIGN(mdp->d_hints, cp);
 687             ival = *(int*)cp;
 688             cp += sizeof(int);
 689             clen = *cp++;
 690             if (verinfo == NULL || ival == verinfo->md_ver_preferred) {
 691                 found = 1;
 692                 break;
 693             }
 694             if (ival >= verinfo->md_ver_minimum &&
 695                 ival <= verinfo->md_ver_maximum &&
 696                 ival > bestver) {
 697                 bestver = ival;
 698                 best = cp;
 699                 blen = clen;
 700             }
 701             break;
 702         default:
 703             break;
 704         }
 705         recptr += reclen + sizeof(int);
 706     }
 707     /*
 708      * Finally check if KLD is in the place
 709      */
 710     if (found)
 711         result = file_lookup(mdp->d_path, cp, clen, NULL);
 712     else if (best)
 713         result = file_lookup(mdp->d_path, best, blen, NULL);
 714 bad:
 715     /*
 716      * If nothing found or hints is absent - fallback to the old way
 717      * by using "kldname[.ko]" as module name.
 718      */
 719     if (!found && !bestver && result == NULL)
 720         result = file_lookup(mdp->d_path, modname, modnamelen, kld_ext_list);
 721     return result;
 722 }
 723
 724 /*
 725  * Attempt to locate the file containing the module (name)
 726  */
 727 static char *
 728 mod_searchmodule(char *name, struct mod_depend *verinfo)
 729 {
 730     struct      moduledir *mdp;
 731     char        *result;
 732
 733     moduledir_rebuild();
 734     /*
 735      * Now we ready to lookup module in the given directories
 736      */
 737     result = NULL;
 738     STAILQ_FOREACH(mdp, &moduledir_list, d_link) {
 739         result = mod_search_hints(mdp, name, verinfo);
 740         if (result)
 741             break;
 742     }
 743
 744     return(result);
 745 }
 746
 747 int
 748 file_addmodule(struct preloaded_file *fp, char *modname, int version,
 749         struct kernel_module **newmp)
 750 {
 751     struct kernel_module *mp;
 752     struct mod_depend mdepend;
 753
 754     bzero(&mdepend, sizeof(mdepend));
 755     mdepend.md_ver_preferred = version;
 756     mp = file_findmodule(fp, modname, &mdepend);
 757     if (mp)
 758         return (EEXIST);
 759     mp = malloc(sizeof(struct kernel_module));
 760     if (mp == NULL)
 761         return (ENOMEM);
 762     bzero(mp, sizeof(struct kernel_module));
 763     mp->m_name = strdup(modname);
 764     mp->m_version = version;
 765     mp->m_fp = fp;
 766     mp->m_next = fp->f_modules;
 767     fp->f_modules = mp;
 768     if (newmp)
 769         *newmp = mp;
 770     return (0);
 771 }
 772
 773 /*
 774  * Throw a file away
 775  */
 776 void
 777 file_discard(struct preloaded_file *fp)
 778 {
 779     struct file_metadata        *md, *md1;
 780     struct kernel_module        *mp, *mp1;
 781     if (fp == NULL)
 782         return;
 783     md = fp->f_metadata;
 784     while (md) {
 785         md1 = md;
 786         md = md->md_next;
 787         free(md1);
 788     }
 789     mp = fp->f_modules;
 790     while (mp) {
 791         if (mp->m_name)
 792             free(mp->m_name);
 793         mp1 = mp;
 794         mp = mp->m_next;
 795         free(mp1);
 796     }
 797     if (fp->f_name != NULL)
 798         free(fp->f_name);
 799     if (fp->f_type != NULL)
 800         free(fp->f_type);
 801     if (fp->f_args != NULL)
 802         free(fp->f_args);
 803     free(fp);
 804 }
 805
 806 /*
 807  * Allocate a new file; must be used instead of malloc()
 808  * to ensure safe initialisation.
 809  */
 810 struct preloaded_file *
 811 file_alloc(void)
 812 {
 813     struct preloaded_file       *fp;
 814
 815     if ((fp = malloc(sizeof(struct preloaded_file))) != NULL) {
 816         bzero(fp, sizeof(struct preloaded_file));
 817     }
 818     return (fp);
 819 }
 820
 821 /*
 822  * Add a module to the chain
 823  */
 824 static void
 825 file_insert_tail(struct preloaded_file *fp)
 826 {
 827     struct preloaded_file       *cm;
 828
 829     /* Append to list of loaded file */
 830     fp->f_next = NULL;
 831     if (preloaded_files == NULL) {
 832         preloaded_files = fp;
 833     } else {
 834         for (cm = preloaded_files; cm->f_next != NULL; cm = cm->f_next)
 835             ;
 836         cm->f_next = fp;
 837     }
 838 }
 839
 840 static char *
 841 moduledir_fullpath(struct moduledir *mdp, const char *fname)
 842 {
 843     char *cp;
 844
 845     cp = malloc(strlen(mdp->d_path) + strlen(fname) + 2);
 846     if (cp == NULL)
 847         return NULL;
 848     strcpy(cp, mdp->d_path);
 849     strcat(cp, "/");
 850     strcat(cp, fname);
 851     return (cp);
 852 }
 853
 854 /*
 855  * Read linker.hints file into memory performing some sanity checks.
 856  */
 857 static void
 858 moduledir_readhints(struct moduledir *mdp)
 859 {
 860     struct stat st;
 861     char        *path;
 862     int         fd, size, version;
 863
 864     if (mdp->d_hints != NULL || (mdp->d_flags & MDIR_NOHINTS))
 865         return;
 866     path = moduledir_fullpath(mdp, "linker.hints");
 867     if (stat(path, &st) != 0 || st.st_size < (sizeof(version) + sizeof(int)) ||
 868         st.st_size > 100 * 1024 || (fd = open(path, O_RDONLY)) < 0) {
 869         free(path);
 870         mdp->d_flags |= MDIR_NOHINTS;
 871         return;
 872     }
 873     free(path);
 874     size = read(fd, &version, sizeof(version));
 875     if (size != sizeof(version) || version != LINKER_HINTS_VERSION)
 876         goto bad;
 877     size = st.st_size - size;
 878     mdp->d_hints = malloc(size);
 879     if (mdp->d_hints == NULL)
 880         goto bad;
 881     if (read(fd, mdp->d_hints, size) != size)
 882         goto bad;
 883     mdp->d_hintsz = size;
 884     close(fd);
 885     return;
 886 bad:
 887     close(fd);
 888     if (mdp->d_hints) {
 889         free(mdp->d_hints);
 890         mdp->d_hints = NULL;
 891     }
 892     mdp->d_flags |= MDIR_NOHINTS;
 893     return;
 894 }
 895
 896 /*
 897  * Extract directories from the ';' separated list, remove duplicates.
 898  */
 899 static void
 900 moduledir_rebuild(void)
 901 {
 902     struct      moduledir *mdp, *mtmp;
 903     const char  *path, *cp, *ep;
 904     int         cplen;
 905
 906     path = getenv("module_path");
 907     if (path == NULL)
 908         path = default_searchpath;
 909     /*
 910      * Rebuild list of module directories if it changed
 911      */
 912     STAILQ_FOREACH(mdp, &moduledir_list, d_link)
 913         mdp->d_flags |= MDIR_REMOVED;
 914
 915     for (ep = path; *ep != 0;  ep++) {
 916         cp = ep;
 917         for (; *ep != 0 && *ep != ';'; ep++)
 918             ;
 919         /*
 920          * Ignore trailing slashes
 921          */
 922         for (cplen = ep - cp; cplen > 1 && cp[cplen - 1] == '/'; cplen--)
 923             ;
 924         STAILQ_FOREACH(mdp, &moduledir_list, d_link) {
 925             if (strlen(mdp->d_path) != cplen || bcmp(cp, mdp->d_path, cplen) != 0)
 926                 continue;
 927             mdp->d_flags &= ~MDIR_REMOVED;
 928             break;
 929         }
 930         if (mdp == NULL) {
 931             mdp = malloc(sizeof(*mdp) + cplen + 1);
 932             if (mdp == NULL)
 933                 return;
 934             mdp->d_path = (char*)(mdp + 1);
 935             bcopy(cp, mdp->d_path, cplen);
 936             mdp->d_path[cplen] = 0;
 937             mdp->d_hints = NULL;
 938             mdp->d_flags = 0;
 939             STAILQ_INSERT_TAIL(&moduledir_list, mdp, d_link);
 940         }
 941         if (*ep == 0)
 942             break;
 943     }
 944     /*
 945      * Delete unused directories if any
 946      */
 947     mdp = STAILQ_FIRST(&moduledir_list);
 948     while (mdp) {
 949         if ((mdp->d_flags & MDIR_REMOVED) == 0) {
 950             mdp = STAILQ_NEXT(mdp, d_link);
 951         } else {
 952             if (mdp->d_hints)
 953                 free(mdp->d_hints);
 954             mtmp = mdp;
 955             mdp = STAILQ_NEXT(mdp, d_link);
 956             STAILQ_REMOVE(&moduledir_list, mtmp, moduledir, d_link);
 957             free(mtmp);
 958         }
 959     }
 960     return;
 961 }