zfsimpl.c

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    1 /*-
    2  * Copyright (c) 2007 Doug Rabson
    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: releng/10.1/sys/boot/zfs/zfsimpl.c 268649 2014-07-15 04:53:34Z delphij $");
   29 
   30 /*
   31  *      Stand-alone ZFS file reader.
   32  */
   33 
   34 #include <sys/stat.h>
   35 #include <sys/stdint.h>
   36 
   37 #include "zfsimpl.h"
   38 #include "zfssubr.c"
   39 
   40 
   41 struct zfsmount {
   42         const spa_t     *spa;
   43         objset_phys_t   objset;
   44         uint64_t        rootobj;
   45 };
   46 
   47 /*
   48  * List of all vdevs, chained through v_alllink.
   49  */
   50 static vdev_list_t zfs_vdevs;
   51 
   52  /*
   53  * List of ZFS features supported for read
   54  */
   55 static const char *features_for_read[] = {
   56         "org.illumos:lz4_compress",
   57         "com.delphix:hole_birth",
   58         "com.delphix:extensible_dataset",
   59         "com.delphix:embedded_data",
   60         NULL
   61 };
   62 
   63 /*
   64  * List of all pools, chained through spa_link.
   65  */
   66 static spa_list_t zfs_pools;
   67 
   68 static uint64_t zfs_crc64_table[256];
   69 static const dnode_phys_t *dnode_cache_obj = 0;
   70 static uint64_t dnode_cache_bn;
   71 static char *dnode_cache_buf;
   72 static char *zap_scratch;
   73 static char *zfs_temp_buf, *zfs_temp_end, *zfs_temp_ptr;
   74 
   75 #define TEMP_SIZE       (1024 * 1024)
   76 
   77 static int zio_read(const spa_t *spa, const blkptr_t *bp, void *buf);
   78 static int zfs_get_root(const spa_t *spa, uint64_t *objid);
   79 static int zfs_rlookup(const spa_t *spa, uint64_t objnum, char *result);
   80 
   81 static void
   82 zfs_init(void)
   83 {
   84         STAILQ_INIT(&zfs_vdevs);
   85         STAILQ_INIT(&zfs_pools);
   86 
   87         zfs_temp_buf = malloc(TEMP_SIZE);
   88         zfs_temp_end = zfs_temp_buf + TEMP_SIZE;
   89         zfs_temp_ptr = zfs_temp_buf;
   90         dnode_cache_buf = malloc(SPA_MAXBLOCKSIZE);
   91         zap_scratch = malloc(SPA_MAXBLOCKSIZE);
   92 
   93         zfs_init_crc();
   94 }
   95 
   96 static void *
   97 zfs_alloc(size_t size)
   98 {
   99         char *ptr;
  100 
  101         if (zfs_temp_ptr + size > zfs_temp_end) {
  102                 printf("ZFS: out of temporary buffer space\n");
  103                 for (;;) ;
  104         }
  105         ptr = zfs_temp_ptr;
  106         zfs_temp_ptr += size;
  107 
  108         return (ptr);
  109 }
  110 
  111 static void
  112 zfs_free(void *ptr, size_t size)
  113 {
  114 
  115         zfs_temp_ptr -= size;
  116         if (zfs_temp_ptr != ptr) {
  117                 printf("ZFS: zfs_alloc()/zfs_free() mismatch\n");
  118                 for (;;) ;
  119         }
  120 }
  121 
  122 static int
  123 xdr_int(const unsigned char **xdr, int *ip)
  124 {
  125         *ip = ((*xdr)[0] << 24)
  126                 | ((*xdr)[1] << 16)
  127                 | ((*xdr)[2] << 8)
  128                 | ((*xdr)[3] << 0);
  129         (*xdr) += 4;
  130         return (0);
  131 }
  132 
  133 static int
  134 xdr_u_int(const unsigned char **xdr, u_int *ip)
  135 {
  136         *ip = ((*xdr)[0] << 24)
  137                 | ((*xdr)[1] << 16)
  138                 | ((*xdr)[2] << 8)
  139                 | ((*xdr)[3] << 0);
  140         (*xdr) += 4;
  141         return (0);
  142 }
  143 
  144 static int
  145 xdr_uint64_t(const unsigned char **xdr, uint64_t *lp)
  146 {
  147         u_int hi, lo;
  148 
  149         xdr_u_int(xdr, &hi);
  150         xdr_u_int(xdr, &lo);
  151         *lp = (((uint64_t) hi) << 32) | lo;
  152         return (0);
  153 }
  154 
  155 static int
  156 nvlist_find(const unsigned char *nvlist, const char *name, int type,
  157             int* elementsp, void *valuep)
  158 {
  159         const unsigned char *p, *pair;
  160         int junk;
  161         int encoded_size, decoded_size;
  162 
  163         p = nvlist;
  164         xdr_int(&p, &junk);
  165         xdr_int(&p, &junk);
  166 
  167         pair = p;
  168         xdr_int(&p, &encoded_size);
  169         xdr_int(&p, &decoded_size);
  170         while (encoded_size && decoded_size) {
  171                 int namelen, pairtype, elements;
  172                 const char *pairname;
  173 
  174                 xdr_int(&p, &namelen);
  175                 pairname = (const char*) p;
  176                 p += roundup(namelen, 4);
  177                 xdr_int(&p, &pairtype);
  178 
  179                 if (!memcmp(name, pairname, namelen) && type == pairtype) {
  180                         xdr_int(&p, &elements);
  181                         if (elementsp)
  182                                 *elementsp = elements;
  183                         if (type == DATA_TYPE_UINT64) {
  184                                 xdr_uint64_t(&p, (uint64_t *) valuep);
  185                                 return (0);
  186                         } else if (type == DATA_TYPE_STRING) {
  187                                 int len;
  188                                 xdr_int(&p, &len);
  189                                 (*(const char**) valuep) = (const char*) p;
  190                                 return (0);
  191                         } else if (type == DATA_TYPE_NVLIST
  192                                    || type == DATA_TYPE_NVLIST_ARRAY) {
  193                                 (*(const unsigned char**) valuep) =
  194                                          (const unsigned char*) p;
  195                                 return (0);
  196                         } else {
  197                                 return (EIO);
  198                         }
  199                 } else {
  200                         /*
  201                          * Not the pair we are looking for, skip to the next one.
  202                          */
  203                         p = pair + encoded_size;
  204                 }
  205 
  206                 pair = p;
  207                 xdr_int(&p, &encoded_size);
  208                 xdr_int(&p, &decoded_size);
  209         }
  210 
  211         return (EIO);
  212 }
  213 
  214 static int
  215 nvlist_check_features_for_read(const unsigned char *nvlist)
  216 {
  217         const unsigned char *p, *pair;
  218         int junk;
  219         int encoded_size, decoded_size;
  220         int rc;
  221 
  222         rc = 0;
  223 
  224         p = nvlist;
  225         xdr_int(&p, &junk);
  226         xdr_int(&p, &junk);
  227 
  228         pair = p;
  229         xdr_int(&p, &encoded_size);
  230         xdr_int(&p, &decoded_size);
  231         while (encoded_size && decoded_size) {
  232                 int namelen, pairtype;
  233                 const char *pairname;
  234                 int i, found;
  235 
  236                 found = 0;
  237 
  238                 xdr_int(&p, &namelen);
  239                 pairname = (const char*) p;
  240                 p += roundup(namelen, 4);
  241                 xdr_int(&p, &pairtype);
  242 
  243                 for (i = 0; features_for_read[i] != NULL; i++) {
  244                         if (!memcmp(pairname, features_for_read[i], namelen)) {
  245                                 found = 1;
  246                                 break;
  247                         }
  248                 }
  249 
  250                 if (!found) {
  251                         printf("ZFS: unsupported feature: %s\n", pairname);
  252                         rc = EIO;
  253                 }
  254 
  255                 p = pair + encoded_size;
  256 
  257                 pair = p;
  258                 xdr_int(&p, &encoded_size);
  259                 xdr_int(&p, &decoded_size);
  260         }
  261 
  262         return (rc);
  263 }
  264 
  265 /*
  266  * Return the next nvlist in an nvlist array.
  267  */
  268 static const unsigned char *
  269 nvlist_next(const unsigned char *nvlist)
  270 {
  271         const unsigned char *p, *pair;
  272         int junk;
  273         int encoded_size, decoded_size;
  274 
  275         p = nvlist;
  276         xdr_int(&p, &junk);
  277         xdr_int(&p, &junk);
  278 
  279         pair = p;
  280         xdr_int(&p, &encoded_size);
  281         xdr_int(&p, &decoded_size);
  282         while (encoded_size && decoded_size) {
  283                 p = pair + encoded_size;
  284 
  285                 pair = p;
  286                 xdr_int(&p, &encoded_size);
  287                 xdr_int(&p, &decoded_size);
  288         }
  289 
  290         return p;
  291 }
  292 
  293 #ifdef TEST
  294 
  295 static const unsigned char *
  296 nvlist_print(const unsigned char *nvlist, unsigned int indent)
  297 {
  298         static const char* typenames[] = {
  299                 "DATA_TYPE_UNKNOWN",
  300                 "DATA_TYPE_BOOLEAN",
  301                 "DATA_TYPE_BYTE",
  302                 "DATA_TYPE_INT16",
  303                 "DATA_TYPE_UINT16",
  304                 "DATA_TYPE_INT32",
  305                 "DATA_TYPE_UINT32",
  306                 "DATA_TYPE_INT64",
  307                 "DATA_TYPE_UINT64",
  308                 "DATA_TYPE_STRING",
  309                 "DATA_TYPE_BYTE_ARRAY",
  310                 "DATA_TYPE_INT16_ARRAY",
  311                 "DATA_TYPE_UINT16_ARRAY",
  312                 "DATA_TYPE_INT32_ARRAY",
  313                 "DATA_TYPE_UINT32_ARRAY",
  314                 "DATA_TYPE_INT64_ARRAY",
  315                 "DATA_TYPE_UINT64_ARRAY",
  316                 "DATA_TYPE_STRING_ARRAY",
  317                 "DATA_TYPE_HRTIME",
  318                 "DATA_TYPE_NVLIST",
  319                 "DATA_TYPE_NVLIST_ARRAY",
  320                 "DATA_TYPE_BOOLEAN_VALUE",
  321                 "DATA_TYPE_INT8",
  322                 "DATA_TYPE_UINT8",
  323                 "DATA_TYPE_BOOLEAN_ARRAY",
  324                 "DATA_TYPE_INT8_ARRAY",
  325                 "DATA_TYPE_UINT8_ARRAY"
  326         };
  327 
  328         unsigned int i, j;
  329         const unsigned char *p, *pair;
  330         int junk;
  331         int encoded_size, decoded_size;
  332 
  333         p = nvlist;
  334         xdr_int(&p, &junk);
  335         xdr_int(&p, &junk);
  336 
  337         pair = p;
  338         xdr_int(&p, &encoded_size);
  339         xdr_int(&p, &decoded_size);
  340         while (encoded_size && decoded_size) {
  341                 int namelen, pairtype, elements;
  342                 const char *pairname;
  343 
  344                 xdr_int(&p, &namelen);
  345                 pairname = (const char*) p;
  346                 p += roundup(namelen, 4);
  347                 xdr_int(&p, &pairtype);
  348 
  349                 for (i = 0; i < indent; i++)
  350                         printf(" ");
  351                 printf("%s %s", typenames[pairtype], pairname);
  352 
  353                 xdr_int(&p, &elements);
  354                 switch (pairtype) {
  355                 case DATA_TYPE_UINT64: {
  356                         uint64_t val;
  357                         xdr_uint64_t(&p, &val);
  358                         printf(" = 0x%jx\n", (uintmax_t)val);
  359                         break;
  360                 }
  361 
  362                 case DATA_TYPE_STRING: {
  363                         int len;
  364                         xdr_int(&p, &len);
  365                         printf(" = \"%s\"\n", p);
  366                         break;
  367                 }
  368 
  369                 case DATA_TYPE_NVLIST:
  370                         printf("\n");
  371                         nvlist_print(p, indent + 1);
  372                         break;
  373 
  374                 case DATA_TYPE_NVLIST_ARRAY:
  375                         for (j = 0; j < elements; j++) {
  376                                 printf("[%d]\n", j);
  377                                 p = nvlist_print(p, indent + 1);
  378                                 if (j != elements - 1) {
  379                                         for (i = 0; i < indent; i++)
  380                                                 printf(" ");
  381                                         printf("%s %s", typenames[pairtype], pairname);
  382                                 }
  383                         }
  384                         break;
  385 
  386                 default:
  387                         printf("\n");
  388                 }
  389 
  390                 p = pair + encoded_size;
  391 
  392                 pair = p;
  393                 xdr_int(&p, &encoded_size);
  394                 xdr_int(&p, &decoded_size);
  395         }
  396 
  397         return p;
  398 }
  399 
  400 #endif
  401 
  402 static int
  403 vdev_read_phys(vdev_t *vdev, const blkptr_t *bp, void *buf,
  404     off_t offset, size_t size)
  405 {
  406         size_t psize;
  407         int rc;
  408 
  409         if (!vdev->v_phys_read)
  410                 return (EIO);
  411 
  412         if (bp) {
  413                 psize = BP_GET_PSIZE(bp);
  414         } else {
  415                 psize = size;
  416         }
  417 
  418         /*printf("ZFS: reading %d bytes at 0x%jx to %p\n", psize, (uintmax_t)offset, buf);*/
  419         rc = vdev->v_phys_read(vdev, vdev->v_read_priv, offset, buf, psize);
  420         if (rc)
  421                 return (rc);
  422         if (bp && zio_checksum_verify(bp, buf))
  423                 return (EIO);
  424 
  425         return (0);
  426 }
  427 
  428 static int
  429 vdev_disk_read(vdev_t *vdev, const blkptr_t *bp, void *buf,
  430     off_t offset, size_t bytes)
  431 {
  432 
  433         return (vdev_read_phys(vdev, bp, buf,
  434                 offset + VDEV_LABEL_START_SIZE, bytes));
  435 }
  436 
  437 
  438 static int
  439 vdev_mirror_read(vdev_t *vdev, const blkptr_t *bp, void *buf,
  440     off_t offset, size_t bytes)
  441 {
  442         vdev_t *kid;
  443         int rc;
  444 
  445         rc = EIO;
  446         STAILQ_FOREACH(kid, &vdev->v_children, v_childlink) {
  447                 if (kid->v_state != VDEV_STATE_HEALTHY)
  448                         continue;
  449                 rc = kid->v_read(kid, bp, buf, offset, bytes);
  450                 if (!rc)
  451                         return (0);
  452         }
  453 
  454         return (rc);
  455 }
  456 
  457 static int
  458 vdev_replacing_read(vdev_t *vdev, const blkptr_t *bp, void *buf,
  459     off_t offset, size_t bytes)
  460 {
  461         vdev_t *kid;
  462 
  463         /*
  464          * Here we should have two kids:
  465          * First one which is the one we are replacing and we can trust
  466          * only this one to have valid data, but it might not be present.
  467          * Second one is that one we are replacing with. It is most likely
  468          * healthy, but we can't trust it has needed data, so we won't use it.
  469          */
  470         kid = STAILQ_FIRST(&vdev->v_children);
  471         if (kid == NULL)
  472                 return (EIO);
  473         if (kid->v_state != VDEV_STATE_HEALTHY)
  474                 return (EIO);
  475         return (kid->v_read(kid, bp, buf, offset, bytes));
  476 }
  477 
  478 static vdev_t *
  479 vdev_find(uint64_t guid)
  480 {
  481         vdev_t *vdev;
  482 
  483         STAILQ_FOREACH(vdev, &zfs_vdevs, v_alllink)
  484                 if (vdev->v_guid == guid)
  485                         return (vdev);
  486 
  487         return (0);
  488 }
  489 
  490 static vdev_t *
  491 vdev_create(uint64_t guid, vdev_read_t *read)
  492 {
  493         vdev_t *vdev;
  494 
  495         vdev = malloc(sizeof(vdev_t));
  496         memset(vdev, 0, sizeof(vdev_t));
  497         STAILQ_INIT(&vdev->v_children);
  498         vdev->v_guid = guid;
  499         vdev->v_state = VDEV_STATE_OFFLINE;
  500         vdev->v_read = read;
  501         vdev->v_phys_read = 0;
  502         vdev->v_read_priv = 0;
  503         STAILQ_INSERT_TAIL(&zfs_vdevs, vdev, v_alllink);
  504 
  505         return (vdev);
  506 }
  507 
  508 static int
  509 vdev_init_from_nvlist(const unsigned char *nvlist, vdev_t *pvdev,
  510     vdev_t **vdevp, int is_newer)
  511 {
  512         int rc;
  513         uint64_t guid, id, ashift, nparity;
  514         const char *type;
  515         const char *path;
  516         vdev_t *vdev, *kid;
  517         const unsigned char *kids;
  518         int nkids, i, is_new;
  519         uint64_t is_offline, is_faulted, is_degraded, is_removed, isnt_present;
  520 
  521         if (nvlist_find(nvlist, ZPOOL_CONFIG_GUID,
  522                         DATA_TYPE_UINT64, 0, &guid)
  523             || nvlist_find(nvlist, ZPOOL_CONFIG_ID,
  524                            DATA_TYPE_UINT64, 0, &id)
  525             || nvlist_find(nvlist, ZPOOL_CONFIG_TYPE,
  526                            DATA_TYPE_STRING, 0, &type)) {
  527                 printf("ZFS: can't find vdev details\n");
  528                 return (ENOENT);
  529         }
  530 
  531         if (strcmp(type, VDEV_TYPE_MIRROR)
  532             && strcmp(type, VDEV_TYPE_DISK)
  533 #ifdef ZFS_TEST
  534             && strcmp(type, VDEV_TYPE_FILE)
  535 #endif
  536             && strcmp(type, VDEV_TYPE_RAIDZ)
  537             && strcmp(type, VDEV_TYPE_REPLACING)) {
  538                 printf("ZFS: can only boot from disk, mirror, raidz1, raidz2 and raidz3 vdevs\n");
  539                 return (EIO);
  540         }
  541 
  542         is_offline = is_removed = is_faulted = is_degraded = isnt_present = 0;
  543 
  544         nvlist_find(nvlist, ZPOOL_CONFIG_OFFLINE, DATA_TYPE_UINT64, 0,
  545                         &is_offline);
  546         nvlist_find(nvlist, ZPOOL_CONFIG_REMOVED, DATA_TYPE_UINT64, 0,
  547                         &is_removed);
  548         nvlist_find(nvlist, ZPOOL_CONFIG_FAULTED, DATA_TYPE_UINT64, 0,
  549                         &is_faulted);
  550         nvlist_find(nvlist, ZPOOL_CONFIG_DEGRADED, DATA_TYPE_UINT64, 0,
  551                         &is_degraded);
  552         nvlist_find(nvlist, ZPOOL_CONFIG_NOT_PRESENT, DATA_TYPE_UINT64, 0,
  553                         &isnt_present);
  554 
  555         vdev = vdev_find(guid);
  556         if (!vdev) {
  557                 is_new = 1;
  558 
  559                 if (!strcmp(type, VDEV_TYPE_MIRROR))
  560                         vdev = vdev_create(guid, vdev_mirror_read);
  561                 else if (!strcmp(type, VDEV_TYPE_RAIDZ))
  562                         vdev = vdev_create(guid, vdev_raidz_read);
  563                 else if (!strcmp(type, VDEV_TYPE_REPLACING))
  564                         vdev = vdev_create(guid, vdev_replacing_read);
  565                 else
  566                         vdev = vdev_create(guid, vdev_disk_read);
  567 
  568                 vdev->v_id = id;
  569                 vdev->v_top = pvdev != NULL ? pvdev : vdev;
  570                 if (nvlist_find(nvlist, ZPOOL_CONFIG_ASHIFT,
  571                         DATA_TYPE_UINT64, 0, &ashift) == 0)
  572                         vdev->v_ashift = ashift;
  573                 else
  574                         vdev->v_ashift = 0;
  575                 if (nvlist_find(nvlist, ZPOOL_CONFIG_NPARITY,
  576                         DATA_TYPE_UINT64, 0, &nparity) == 0)
  577                         vdev->v_nparity = nparity;
  578                 else
  579                         vdev->v_nparity = 0;
  580                 if (nvlist_find(nvlist, ZPOOL_CONFIG_PATH,
  581                                 DATA_TYPE_STRING, 0, &path) == 0) {
  582                         if (strncmp(path, "/dev/", 5) == 0)
  583                                 path += 5;
  584                         vdev->v_name = strdup(path);
  585                 } else {
  586                         if (!strcmp(type, "raidz")) {
  587                                 if (vdev->v_nparity == 1)
  588                                         vdev->v_name = "raidz1";
  589                                 else if (vdev->v_nparity == 2)
  590                                         vdev->v_name = "raidz2";
  591                                 else if (vdev->v_nparity == 3)
  592                                         vdev->v_name = "raidz3";
  593                                 else {
  594                                         printf("ZFS: can only boot from disk, mirror, raidz1, raidz2 and raidz3 vdevs\n");
  595                                         return (EIO);
  596                                 }
  597                         } else {
  598                                 vdev->v_name = strdup(type);
  599                         }
  600                 }
  601         } else {
  602                 is_new = 0;
  603         }
  604 
  605         if (is_new || is_newer) {
  606                 /*
  607                  * This is either new vdev or we've already seen this vdev,
  608                  * but from an older vdev label, so let's refresh its state
  609                  * from the newer label.
  610                  */
  611                 if (is_offline)
  612                         vdev->v_state = VDEV_STATE_OFFLINE;
  613                 else if (is_removed)
  614                         vdev->v_state = VDEV_STATE_REMOVED;
  615                 else if (is_faulted)
  616                         vdev->v_state = VDEV_STATE_FAULTED;
  617                 else if (is_degraded)
  618                         vdev->v_state = VDEV_STATE_DEGRADED;
  619                 else if (isnt_present)
  620                         vdev->v_state = VDEV_STATE_CANT_OPEN;
  621         }
  622 
  623         rc = nvlist_find(nvlist, ZPOOL_CONFIG_CHILDREN,
  624                          DATA_TYPE_NVLIST_ARRAY, &nkids, &kids);
  625         /*
  626          * Its ok if we don't have any kids.
  627          */
  628         if (rc == 0) {
  629                 vdev->v_nchildren = nkids;
  630                 for (i = 0; i < nkids; i++) {
  631                         rc = vdev_init_from_nvlist(kids, vdev, &kid, is_newer);
  632                         if (rc)
  633                                 return (rc);
  634                         if (is_new)
  635                                 STAILQ_INSERT_TAIL(&vdev->v_children, kid,
  636                                                    v_childlink);
  637                         kids = nvlist_next(kids);
  638                 }
  639         } else {
  640                 vdev->v_nchildren = 0;
  641         }
  642 
  643         if (vdevp)
  644                 *vdevp = vdev;
  645         return (0);
  646 }
  647 
  648 static void
  649 vdev_set_state(vdev_t *vdev)
  650 {
  651         vdev_t *kid;
  652         int good_kids;
  653         int bad_kids;
  654 
  655         /*
  656          * A mirror or raidz is healthy if all its kids are healthy. A
  657          * mirror is degraded if any of its kids is healthy; a raidz
  658          * is degraded if at most nparity kids are offline.
  659          */
  660         if (STAILQ_FIRST(&vdev->v_children)) {
  661                 good_kids = 0;
  662                 bad_kids = 0;
  663                 STAILQ_FOREACH(kid, &vdev->v_children, v_childlink) {
  664                         if (kid->v_state == VDEV_STATE_HEALTHY)
  665                                 good_kids++;
  666                         else
  667                                 bad_kids++;
  668                 }
  669                 if (bad_kids == 0) {
  670                         vdev->v_state = VDEV_STATE_HEALTHY;
  671                 } else {
  672                         if (vdev->v_read == vdev_mirror_read) {
  673                                 if (good_kids) {
  674                                         vdev->v_state = VDEV_STATE_DEGRADED;
  675                                 } else {
  676                                         vdev->v_state = VDEV_STATE_OFFLINE;
  677                                 }
  678                         } else if (vdev->v_read == vdev_raidz_read) {
  679                                 if (bad_kids > vdev->v_nparity) {
  680                                         vdev->v_state = VDEV_STATE_OFFLINE;
  681                                 } else {
  682                                         vdev->v_state = VDEV_STATE_DEGRADED;
  683                                 }
  684                         }
  685                 }
  686         }
  687 }
  688 
  689 static spa_t *
  690 spa_find_by_guid(uint64_t guid)
  691 {
  692         spa_t *spa;
  693 
  694         STAILQ_FOREACH(spa, &zfs_pools, spa_link)
  695                 if (spa->spa_guid == guid)
  696                         return (spa);
  697 
  698         return (0);
  699 }
  700 
  701 static spa_t *
  702 spa_find_by_name(const char *name)
  703 {
  704         spa_t *spa;
  705 
  706         STAILQ_FOREACH(spa, &zfs_pools, spa_link)
  707                 if (!strcmp(spa->spa_name, name))
  708                         return (spa);
  709 
  710         return (0);
  711 }
  712 
  713 #ifdef BOOT2
  714 static spa_t *
  715 spa_get_primary(void)
  716 {
  717 
  718         return (STAILQ_FIRST(&zfs_pools));
  719 }
  720 
  721 static vdev_t *
  722 spa_get_primary_vdev(const spa_t *spa)
  723 {
  724         vdev_t *vdev;
  725         vdev_t *kid;
  726 
  727         if (spa == NULL)
  728                 spa = spa_get_primary();
  729         if (spa == NULL)
  730                 return (NULL);
  731         vdev = STAILQ_FIRST(&spa->spa_vdevs);
  732         if (vdev == NULL)
  733                 return (NULL);
  734         for (kid = STAILQ_FIRST(&vdev->v_children); kid != NULL;
  735              kid = STAILQ_FIRST(&vdev->v_children))
  736                 vdev = kid;
  737         return (vdev);
  738 }
  739 #endif
  740 
  741 static spa_t *
  742 spa_create(uint64_t guid)
  743 {
  744         spa_t *spa;
  745 
  746         spa = malloc(sizeof(spa_t));
  747         memset(spa, 0, sizeof(spa_t));
  748         STAILQ_INIT(&spa->spa_vdevs);
  749         spa->spa_guid = guid;
  750         STAILQ_INSERT_TAIL(&zfs_pools, spa, spa_link);
  751 
  752         return (spa);
  753 }
  754 
  755 static const char *
  756 state_name(vdev_state_t state)
  757 {
  758         static const char* names[] = {
  759                 "UNKNOWN",
  760                 "CLOSED",
  761                 "OFFLINE",
  762                 "REMOVED",
  763                 "CANT_OPEN",
  764                 "FAULTED",
  765                 "DEGRADED",
  766                 "ONLINE"
  767         };
  768         return names[state];
  769 }
  770 
  771 #ifdef BOOT2
  772 
  773 #define pager_printf printf
  774 
  775 #else
  776 
  777 static void
  778 pager_printf(const char *fmt, ...)
  779 {
  780         char line[80];
  781         va_list args;
  782 
  783         va_start(args, fmt);
  784         vsprintf(line, fmt, args);
  785         va_end(args);
  786         pager_output(line);
  787 }
  788 
  789 #endif
  790 
  791 #define STATUS_FORMAT   "        %s %s\n"
  792 
  793 static void
  794 print_state(int indent, const char *name, vdev_state_t state)
  795 {
  796         int i;
  797         char buf[512];
  798 
  799         buf[0] = 0;
  800         for (i = 0; i < indent; i++)
  801                 strcat(buf, "  ");
  802         strcat(buf, name);
  803         pager_printf(STATUS_FORMAT, buf, state_name(state));
  804         
  805 }
  806 
  807 static void
  808 vdev_status(vdev_t *vdev, int indent)
  809 {
  810         vdev_t *kid;
  811         print_state(indent, vdev->v_name, vdev->v_state);
  812 
  813         STAILQ_FOREACH(kid, &vdev->v_children, v_childlink) {
  814                 vdev_status(kid, indent + 1);
  815         }
  816 }
  817 
  818 static void
  819 spa_status(spa_t *spa)
  820 {
  821         static char bootfs[ZFS_MAXNAMELEN];
  822         uint64_t rootid;
  823         vdev_t *vdev;
  824         int good_kids, bad_kids, degraded_kids;
  825         vdev_state_t state;
  826 
  827         pager_printf("  pool: %s\n", spa->spa_name);
  828         if (zfs_get_root(spa, &rootid) == 0 &&
  829             zfs_rlookup(spa, rootid, bootfs) == 0) {
  830                 if (bootfs[0] == '\0')
  831                         pager_printf("bootfs: %s\n", spa->spa_name);
  832                 else
  833                         pager_printf("bootfs: %s/%s\n", spa->spa_name, bootfs);
  834         }
  835         pager_printf("config:\n\n");
  836         pager_printf(STATUS_FORMAT, "NAME", "STATE");
  837 
  838         good_kids = 0;
  839         degraded_kids = 0;
  840         bad_kids = 0;
  841         STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink) {
  842                 if (vdev->v_state == VDEV_STATE_HEALTHY)
  843                         good_kids++;
  844                 else if (vdev->v_state == VDEV_STATE_DEGRADED)
  845                         degraded_kids++;
  846                 else
  847                         bad_kids++;
  848         }
  849 
  850         state = VDEV_STATE_CLOSED;
  851         if (good_kids > 0 && (degraded_kids + bad_kids) == 0)
  852                 state = VDEV_STATE_HEALTHY;
  853         else if ((good_kids + degraded_kids) > 0)
  854                 state = VDEV_STATE_DEGRADED;
  855 
  856         print_state(0, spa->spa_name, state);
  857         STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink) {
  858                 vdev_status(vdev, 1);
  859         }
  860 }
  861 
  862 static void
  863 spa_all_status(void)
  864 {
  865         spa_t *spa;
  866         int first = 1;
  867 
  868         STAILQ_FOREACH(spa, &zfs_pools, spa_link) {
  869                 if (!first)
  870                         pager_printf("\n");
  871                 first = 0;
  872                 spa_status(spa);
  873         }
  874 }
  875 
  876 static int
  877 vdev_probe(vdev_phys_read_t *read, void *read_priv, spa_t **spap)
  878 {
  879         vdev_t vtmp;
  880         vdev_phys_t *vdev_label = (vdev_phys_t *) zap_scratch;
  881         spa_t *spa;
  882         vdev_t *vdev, *top_vdev, *pool_vdev;
  883         off_t off;
  884         blkptr_t bp;
  885         const unsigned char *nvlist;
  886         uint64_t val;
  887         uint64_t guid;
  888         uint64_t pool_txg, pool_guid;
  889         uint64_t is_log;
  890         const char *pool_name;
  891         const unsigned char *vdevs;
  892         const unsigned char *features;
  893         int i, rc, is_newer;
  894         char *upbuf;
  895         const struct uberblock *up;
  896 
  897         /*
  898          * Load the vdev label and figure out which
  899          * uberblock is most current.
  900          */
  901         memset(&vtmp, 0, sizeof(vtmp));
  902         vtmp.v_phys_read = read;
  903         vtmp.v_read_priv = read_priv;
  904         off = offsetof(vdev_label_t, vl_vdev_phys);
  905         BP_ZERO(&bp);
  906         BP_SET_LSIZE(&bp, sizeof(vdev_phys_t));
  907         BP_SET_PSIZE(&bp, sizeof(vdev_phys_t));
  908         BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL);
  909         BP_SET_COMPRESS(&bp, ZIO_COMPRESS_OFF);
  910         DVA_SET_OFFSET(BP_IDENTITY(&bp), off);
  911         ZIO_SET_CHECKSUM(&bp.blk_cksum, off, 0, 0, 0);
  912         if (vdev_read_phys(&vtmp, &bp, vdev_label, off, 0))
  913                 return (EIO);
  914 
  915         if (vdev_label->vp_nvlist[0] != NV_ENCODE_XDR) {
  916                 return (EIO);
  917         }
  918 
  919         nvlist = (const unsigned char *) vdev_label->vp_nvlist + 4;
  920 
  921         if (nvlist_find(nvlist,
  922                         ZPOOL_CONFIG_VERSION,
  923                         DATA_TYPE_UINT64, 0, &val)) {
  924                 return (EIO);
  925         }
  926 
  927         if (!SPA_VERSION_IS_SUPPORTED(val)) {
  928                 printf("ZFS: unsupported ZFS version %u (should be %u)\n",
  929                     (unsigned) val, (unsigned) SPA_VERSION);
  930                 return (EIO);
  931         }
  932 
  933         /* Check ZFS features for read */
  934         if (nvlist_find(nvlist,
  935                         ZPOOL_CONFIG_FEATURES_FOR_READ,
  936                         DATA_TYPE_NVLIST, 0, &features) == 0
  937             && nvlist_check_features_for_read(features) != 0)
  938                 return (EIO);
  939 
  940         if (nvlist_find(nvlist,
  941                         ZPOOL_CONFIG_POOL_STATE,
  942                         DATA_TYPE_UINT64, 0, &val)) {
  943                 return (EIO);
  944         }
  945 
  946         if (val == POOL_STATE_DESTROYED) {
  947                 /* We don't boot only from destroyed pools. */
  948                 return (EIO);
  949         }
  950 
  951         if (nvlist_find(nvlist,
  952                         ZPOOL_CONFIG_POOL_TXG,
  953                         DATA_TYPE_UINT64, 0, &pool_txg)
  954             || nvlist_find(nvlist,
  955                            ZPOOL_CONFIG_POOL_GUID,
  956                            DATA_TYPE_UINT64, 0, &pool_guid)
  957             || nvlist_find(nvlist,
  958                            ZPOOL_CONFIG_POOL_NAME,
  959                            DATA_TYPE_STRING, 0, &pool_name)) {
  960                 /*
  961                  * Cache and spare devices end up here - just ignore
  962                  * them.
  963                  */
  964                 /*printf("ZFS: can't find pool details\n");*/
  965                 return (EIO);
  966         }
  967 
  968         is_log = 0;
  969         (void) nvlist_find(nvlist, ZPOOL_CONFIG_IS_LOG, DATA_TYPE_UINT64, 0,
  970             &is_log);
  971         if (is_log)
  972                 return (EIO);
  973 
  974         /*
  975          * Create the pool if this is the first time we've seen it.
  976          */
  977         spa = spa_find_by_guid(pool_guid);
  978         if (!spa) {
  979                 spa = spa_create(pool_guid);
  980                 spa->spa_name = strdup(pool_name);
  981         }
  982         if (pool_txg > spa->spa_txg) {
  983                 spa->spa_txg = pool_txg;
  984                 is_newer = 1;
  985         } else
  986                 is_newer = 0;
  987 
  988         /*
  989          * Get the vdev tree and create our in-core copy of it.
  990          * If we already have a vdev with this guid, this must
  991          * be some kind of alias (overlapping slices, dangerously dedicated
  992          * disks etc).
  993          */
  994         if (nvlist_find(nvlist,
  995                         ZPOOL_CONFIG_GUID,
  996                         DATA_TYPE_UINT64, 0, &guid)) {
  997                 return (EIO);
  998         }
  999         vdev = vdev_find(guid);
 1000         if (vdev && vdev->v_phys_read)  /* Has this vdev already been inited? */
 1001                 return (EIO);
 1002 
 1003         if (nvlist_find(nvlist,
 1004                         ZPOOL_CONFIG_VDEV_TREE,
 1005                         DATA_TYPE_NVLIST, 0, &vdevs)) {
 1006                 return (EIO);
 1007         }
 1008 
 1009         rc = vdev_init_from_nvlist(vdevs, NULL, &top_vdev, is_newer);
 1010         if (rc)
 1011                 return (rc);
 1012 
 1013         /*
 1014          * Add the toplevel vdev to the pool if its not already there.
 1015          */
 1016         STAILQ_FOREACH(pool_vdev, &spa->spa_vdevs, v_childlink)
 1017                 if (top_vdev == pool_vdev)
 1018                         break;
 1019         if (!pool_vdev && top_vdev)
 1020                 STAILQ_INSERT_TAIL(&spa->spa_vdevs, top_vdev, v_childlink);
 1021 
 1022         /*
 1023          * We should already have created an incomplete vdev for this
 1024          * vdev. Find it and initialise it with our read proc.
 1025          */
 1026         vdev = vdev_find(guid);
 1027         if (vdev) {
 1028                 vdev->v_phys_read = read;
 1029                 vdev->v_read_priv = read_priv;
 1030                 vdev->v_state = VDEV_STATE_HEALTHY;
 1031         } else {
 1032                 printf("ZFS: inconsistent nvlist contents\n");
 1033                 return (EIO);
 1034         }
 1035 
 1036         /*
 1037          * Re-evaluate top-level vdev state.
 1038          */
 1039         vdev_set_state(top_vdev);
 1040 
 1041         /*
 1042          * Ok, we are happy with the pool so far. Lets find
 1043          * the best uberblock and then we can actually access
 1044          * the contents of the pool.
 1045          */
 1046         upbuf = zfs_alloc(VDEV_UBERBLOCK_SIZE(vdev));
 1047         up = (const struct uberblock *)upbuf;
 1048         for (i = 0;
 1049              i < VDEV_UBERBLOCK_COUNT(vdev);
 1050              i++) {
 1051                 off = VDEV_UBERBLOCK_OFFSET(vdev, i);
 1052                 BP_ZERO(&bp);
 1053                 DVA_SET_OFFSET(&bp.blk_dva[0], off);
 1054                 BP_SET_LSIZE(&bp, VDEV_UBERBLOCK_SIZE(vdev));
 1055                 BP_SET_PSIZE(&bp, VDEV_UBERBLOCK_SIZE(vdev));
 1056                 BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL);
 1057                 BP_SET_COMPRESS(&bp, ZIO_COMPRESS_OFF);
 1058                 ZIO_SET_CHECKSUM(&bp.blk_cksum, off, 0, 0, 0);
 1059 
 1060                 if (vdev_read_phys(vdev, &bp, upbuf, off, 0))
 1061                         continue;
 1062 
 1063                 if (up->ub_magic != UBERBLOCK_MAGIC)
 1064                         continue;
 1065                 if (up->ub_txg < spa->spa_txg)
 1066                         continue;
 1067                 if (up->ub_txg > spa->spa_uberblock.ub_txg) {
 1068                         spa->spa_uberblock = *up;
 1069                 } else if (up->ub_txg == spa->spa_uberblock.ub_txg) {
 1070                         if (up->ub_timestamp > spa->spa_uberblock.ub_timestamp)
 1071                                 spa->spa_uberblock = *up;
 1072                 }
 1073         }
 1074         zfs_free(upbuf, VDEV_UBERBLOCK_SIZE(vdev));
 1075 
 1076         if (spap)
 1077                 *spap = spa;
 1078         return (0);
 1079 }
 1080 
 1081 static int
 1082 ilog2(int n)
 1083 {
 1084         int v;
 1085 
 1086         for (v = 0; v < 32; v++)
 1087                 if (n == (1 << v))
 1088                         return v;
 1089         return -1;
 1090 }
 1091 
 1092 static int
 1093 zio_read_gang(const spa_t *spa, const blkptr_t *bp, void *buf)
 1094 {
 1095         blkptr_t gbh_bp;
 1096         zio_gbh_phys_t zio_gb;
 1097         char *pbuf;
 1098         int i;
 1099 
 1100         /* Artificial BP for gang block header. */
 1101         gbh_bp = *bp;
 1102         BP_SET_PSIZE(&gbh_bp, SPA_GANGBLOCKSIZE);
 1103         BP_SET_LSIZE(&gbh_bp, SPA_GANGBLOCKSIZE);
 1104         BP_SET_CHECKSUM(&gbh_bp, ZIO_CHECKSUM_GANG_HEADER);
 1105         BP_SET_COMPRESS(&gbh_bp, ZIO_COMPRESS_OFF);
 1106         for (i = 0; i < SPA_DVAS_PER_BP; i++)
 1107                 DVA_SET_GANG(&gbh_bp.blk_dva[i], 0);
 1108 
 1109         /* Read gang header block using the artificial BP. */
 1110         if (zio_read(spa, &gbh_bp, &zio_gb))
 1111                 return (EIO);
 1112 
 1113         pbuf = buf;
 1114         for (i = 0; i < SPA_GBH_NBLKPTRS; i++) {
 1115                 blkptr_t *gbp = &zio_gb.zg_blkptr[i];
 1116 
 1117                 if (BP_IS_HOLE(gbp))
 1118                         continue;
 1119                 if (zio_read(spa, gbp, pbuf))
 1120                         return (EIO);
 1121                 pbuf += BP_GET_PSIZE(gbp);
 1122         }
 1123 
 1124         if (zio_checksum_verify(bp, buf))
 1125                 return (EIO);
 1126         return (0);
 1127 }
 1128 
 1129 static int
 1130 zio_read(const spa_t *spa, const blkptr_t *bp, void *buf)
 1131 {
 1132         int cpfunc = BP_GET_COMPRESS(bp);
 1133         uint64_t align, size;
 1134         void *pbuf;
 1135         int i, error;
 1136 
 1137         /*
 1138          * Process data embedded in block pointer
 1139          */
 1140         if (BP_IS_EMBEDDED(bp)) {
 1141                 ASSERT(BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA);
 1142 
 1143                 size = BPE_GET_PSIZE(bp);
 1144                 ASSERT(size <= BPE_PAYLOAD_SIZE);
 1145 
 1146                 if (cpfunc != ZIO_COMPRESS_OFF)
 1147                         pbuf = zfs_alloc(size);
 1148                 else
 1149                         pbuf = buf;
 1150 
 1151                 decode_embedded_bp_compressed(bp, pbuf);
 1152                 error = 0;
 1153 
 1154                 if (cpfunc != ZIO_COMPRESS_OFF) {
 1155                         error = zio_decompress_data(cpfunc, pbuf,
 1156                             size, buf, BP_GET_LSIZE(bp));
 1157                         zfs_free(pbuf, size);
 1158                 }
 1159                 if (error != 0)
 1160                         printf("ZFS: i/o error - unable to decompress block pointer data, error %d\n",
 1161                             error);
 1162                 return (error);
 1163         }
 1164 
 1165         error = EIO;
 1166 
 1167         for (i = 0; i < SPA_DVAS_PER_BP; i++) {
 1168                 const dva_t *dva = &bp->blk_dva[i];
 1169                 vdev_t *vdev;
 1170                 int vdevid;
 1171                 off_t offset;
 1172 
 1173                 if (!dva->dva_word[0] && !dva->dva_word[1])
 1174                         continue;
 1175 
 1176                 vdevid = DVA_GET_VDEV(dva);
 1177                 offset = DVA_GET_OFFSET(dva);
 1178                 STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink) {
 1179                         if (vdev->v_id == vdevid)
 1180                                 break;
 1181                 }
 1182                 if (!vdev || !vdev->v_read)
 1183                         continue;
 1184 
 1185                 size = BP_GET_PSIZE(bp);
 1186                 if (vdev->v_read == vdev_raidz_read) {
 1187                         align = 1ULL << vdev->v_top->v_ashift;
 1188                         if (P2PHASE(size, align) != 0)
 1189                                 size = P2ROUNDUP(size, align);
 1190                 }
 1191                 if (size != BP_GET_PSIZE(bp) || cpfunc != ZIO_COMPRESS_OFF)
 1192                         pbuf = zfs_alloc(size);
 1193                 else
 1194                         pbuf = buf;
 1195 
 1196                 if (DVA_GET_GANG(dva))
 1197                         error = zio_read_gang(spa, bp, pbuf);
 1198                 else
 1199                         error = vdev->v_read(vdev, bp, pbuf, offset, size);
 1200                 if (error == 0) {
 1201                         if (cpfunc != ZIO_COMPRESS_OFF)
 1202                                 error = zio_decompress_data(cpfunc, pbuf,
 1203                                     BP_GET_PSIZE(bp), buf, BP_GET_LSIZE(bp));
 1204                         else if (size != BP_GET_PSIZE(bp))
 1205                                 bcopy(pbuf, buf, BP_GET_PSIZE(bp));
 1206                 }
 1207                 if (buf != pbuf)
 1208                         zfs_free(pbuf, size);
 1209                 if (error == 0)
 1210                         break;
 1211         }
 1212         if (error != 0)
 1213                 printf("ZFS: i/o error - all block copies unavailable\n");
 1214         return (error);
 1215 }
 1216 
 1217 static int
 1218 dnode_read(const spa_t *spa, const dnode_phys_t *dnode, off_t offset, void *buf, size_t buflen)
 1219 {
 1220         int ibshift = dnode->dn_indblkshift - SPA_BLKPTRSHIFT;
 1221         int bsize = dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 1222         int nlevels = dnode->dn_nlevels;
 1223         int i, rc;
 1224 
 1225         /*
 1226          * Note: bsize may not be a power of two here so we need to do an
 1227          * actual divide rather than a bitshift.
 1228          */
 1229         while (buflen > 0) {
 1230                 uint64_t bn = offset / bsize;
 1231                 int boff = offset % bsize;
 1232                 int ibn;
 1233                 const blkptr_t *indbp;
 1234                 blkptr_t bp;
 1235 
 1236                 if (bn > dnode->dn_maxblkid)
 1237                         return (EIO);
 1238 
 1239                 if (dnode == dnode_cache_obj && bn == dnode_cache_bn)
 1240                         goto cached;
 1241 
 1242                 indbp = dnode->dn_blkptr;
 1243                 for (i = 0; i < nlevels; i++) {
 1244                         /*
 1245                          * Copy the bp from the indirect array so that
 1246                          * we can re-use the scratch buffer for multi-level
 1247                          * objects.
 1248                          */
 1249                         ibn = bn >> ((nlevels - i - 1) * ibshift);
 1250                         ibn &= ((1 << ibshift) - 1);
 1251                         bp = indbp[ibn];
 1252                         rc = zio_read(spa, &bp, dnode_cache_buf);
 1253                         if (rc)
 1254                                 return (rc);
 1255                         indbp = (const blkptr_t *) dnode_cache_buf;
 1256                 }
 1257                 dnode_cache_obj = dnode;
 1258                 dnode_cache_bn = bn;
 1259         cached:
 1260 
 1261                 /*
 1262                  * The buffer contains our data block. Copy what we
 1263                  * need from it and loop.
 1264                  */ 
 1265                 i = bsize - boff;
 1266                 if (i > buflen) i = buflen;
 1267                 memcpy(buf, &dnode_cache_buf[boff], i);
 1268                 buf = ((char*) buf) + i;
 1269                 offset += i;
 1270                 buflen -= i;
 1271         }
 1272 
 1273         return (0);
 1274 }
 1275 
 1276 /*
 1277  * Lookup a value in a microzap directory. Assumes that the zap
 1278  * scratch buffer contains the directory contents.
 1279  */
 1280 static int
 1281 mzap_lookup(const dnode_phys_t *dnode, const char *name, uint64_t *value)
 1282 {
 1283         const mzap_phys_t *mz;
 1284         const mzap_ent_phys_t *mze;
 1285         size_t size;
 1286         int chunks, i;
 1287 
 1288         /*
 1289          * Microzap objects use exactly one block. Read the whole
 1290          * thing.
 1291          */
 1292         size = dnode->dn_datablkszsec * 512;
 1293 
 1294         mz = (const mzap_phys_t *) zap_scratch;
 1295         chunks = size / MZAP_ENT_LEN - 1;
 1296 
 1297         for (i = 0; i < chunks; i++) {
 1298                 mze = &mz->mz_chunk[i];
 1299                 if (!strcmp(mze->mze_name, name)) {
 1300                         *value = mze->mze_value;
 1301                         return (0);
 1302                 }
 1303         }
 1304 
 1305         return (ENOENT);
 1306 }
 1307 
 1308 /*
 1309  * Compare a name with a zap leaf entry. Return non-zero if the name
 1310  * matches.
 1311  */
 1312 static int
 1313 fzap_name_equal(const zap_leaf_t *zl, const zap_leaf_chunk_t *zc, const char *name)
 1314 {
 1315         size_t namelen;
 1316         const zap_leaf_chunk_t *nc;
 1317         const char *p;
 1318 
 1319         namelen = zc->l_entry.le_name_numints;
 1320                         
 1321         nc = &ZAP_LEAF_CHUNK(zl, zc->l_entry.le_name_chunk);
 1322         p = name;
 1323         while (namelen > 0) {
 1324                 size_t len;
 1325                 len = namelen;
 1326                 if (len > ZAP_LEAF_ARRAY_BYTES)
 1327                         len = ZAP_LEAF_ARRAY_BYTES;
 1328                 if (memcmp(p, nc->l_array.la_array, len))
 1329                         return (0);
 1330                 p += len;
 1331                 namelen -= len;
 1332                 nc = &ZAP_LEAF_CHUNK(zl, nc->l_array.la_next);
 1333         }
 1334 
 1335         return 1;
 1336 }
 1337 
 1338 /*
 1339  * Extract a uint64_t value from a zap leaf entry.
 1340  */
 1341 static uint64_t
 1342 fzap_leaf_value(const zap_leaf_t *zl, const zap_leaf_chunk_t *zc)
 1343 {
 1344         const zap_leaf_chunk_t *vc;
 1345         int i;
 1346         uint64_t value;
 1347         const uint8_t *p;
 1348 
 1349         vc = &ZAP_LEAF_CHUNK(zl, zc->l_entry.le_value_chunk);
 1350         for (i = 0, value = 0, p = vc->l_array.la_array; i < 8; i++) {
 1351                 value = (value << 8) | p[i];
 1352         }
 1353 
 1354         return value;
 1355 }
 1356 
 1357 /*
 1358  * Lookup a value in a fatzap directory. Assumes that the zap scratch
 1359  * buffer contains the directory header.
 1360  */
 1361 static int
 1362 fzap_lookup(const spa_t *spa, const dnode_phys_t *dnode, const char *name, uint64_t *value)
 1363 {
 1364         int bsize = dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 1365         zap_phys_t zh = *(zap_phys_t *) zap_scratch;
 1366         fat_zap_t z;
 1367         uint64_t *ptrtbl;
 1368         uint64_t hash;
 1369         int rc;
 1370 
 1371         if (zh.zap_magic != ZAP_MAGIC)
 1372                 return (EIO);
 1373 
 1374         z.zap_block_shift = ilog2(bsize);
 1375         z.zap_phys = (zap_phys_t *) zap_scratch;
 1376 
 1377         /*
 1378          * Figure out where the pointer table is and read it in if necessary.
 1379          */
 1380         if (zh.zap_ptrtbl.zt_blk) {
 1381                 rc = dnode_read(spa, dnode, zh.zap_ptrtbl.zt_blk * bsize,
 1382                                zap_scratch, bsize);
 1383                 if (rc)
 1384                         return (rc);
 1385                 ptrtbl = (uint64_t *) zap_scratch;
 1386         } else {
 1387                 ptrtbl = &ZAP_EMBEDDED_PTRTBL_ENT(&z, 0);
 1388         }
 1389 
 1390         hash = zap_hash(zh.zap_salt, name);
 1391 
 1392         zap_leaf_t zl;
 1393         zl.l_bs = z.zap_block_shift;
 1394 
 1395         off_t off = ptrtbl[hash >> (64 - zh.zap_ptrtbl.zt_shift)] << zl.l_bs;
 1396         zap_leaf_chunk_t *zc;
 1397 
 1398         rc = dnode_read(spa, dnode, off, zap_scratch, bsize);
 1399         if (rc)
 1400                 return (rc);
 1401 
 1402         zl.l_phys = (zap_leaf_phys_t *) zap_scratch;
 1403 
 1404         /*
 1405          * Make sure this chunk matches our hash.
 1406          */
 1407         if (zl.l_phys->l_hdr.lh_prefix_len > 0
 1408             && zl.l_phys->l_hdr.lh_prefix
 1409             != hash >> (64 - zl.l_phys->l_hdr.lh_prefix_len))
 1410                 return (ENOENT);
 1411 
 1412         /*
 1413          * Hash within the chunk to find our entry.
 1414          */
 1415         int shift = (64 - ZAP_LEAF_HASH_SHIFT(&zl) - zl.l_phys->l_hdr.lh_prefix_len);
 1416         int h = (hash >> shift) & ((1 << ZAP_LEAF_HASH_SHIFT(&zl)) - 1);
 1417         h = zl.l_phys->l_hash[h];
 1418         if (h == 0xffff)
 1419                 return (ENOENT);
 1420         zc = &ZAP_LEAF_CHUNK(&zl, h);
 1421         while (zc->l_entry.le_hash != hash) {
 1422                 if (zc->l_entry.le_next == 0xffff) {
 1423                         zc = 0;
 1424                         break;
 1425                 }
 1426                 zc = &ZAP_LEAF_CHUNK(&zl, zc->l_entry.le_next);
 1427         }
 1428         if (fzap_name_equal(&zl, zc, name)) {
 1429                 if (zc->l_entry.le_value_intlen * zc->l_entry.le_value_numints > 8)
 1430                         return (E2BIG);
 1431                 *value = fzap_leaf_value(&zl, zc);
 1432                 return (0);
 1433         }
 1434 
 1435         return (ENOENT);
 1436 }
 1437 
 1438 /*
 1439  * Lookup a name in a zap object and return its value as a uint64_t.
 1440  */
 1441 static int
 1442 zap_lookup(const spa_t *spa, const dnode_phys_t *dnode, const char *name, uint64_t *value)
 1443 {
 1444         int rc;
 1445         uint64_t zap_type;
 1446         size_t size = dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 1447 
 1448         rc = dnode_read(spa, dnode, 0, zap_scratch, size);
 1449         if (rc)
 1450                 return (rc);
 1451 
 1452         zap_type = *(uint64_t *) zap_scratch;
 1453         if (zap_type == ZBT_MICRO)
 1454                 return mzap_lookup(dnode, name, value);
 1455         else if (zap_type == ZBT_HEADER)
 1456                 return fzap_lookup(spa, dnode, name, value);
 1457         printf("ZFS: invalid zap_type=%d\n", (int)zap_type);
 1458         return (EIO);
 1459 }
 1460 
 1461 /*
 1462  * List a microzap directory. Assumes that the zap scratch buffer contains
 1463  * the directory contents.
 1464  */
 1465 static int
 1466 mzap_list(const dnode_phys_t *dnode)
 1467 {
 1468         const mzap_phys_t *mz;
 1469         const mzap_ent_phys_t *mze;
 1470         size_t size;
 1471         int chunks, i;
 1472 
 1473         /*
 1474          * Microzap objects use exactly one block. Read the whole
 1475          * thing.
 1476          */
 1477         size = dnode->dn_datablkszsec * 512;
 1478         mz = (const mzap_phys_t *) zap_scratch;
 1479         chunks = size / MZAP_ENT_LEN - 1;
 1480 
 1481         for (i = 0; i < chunks; i++) {
 1482                 mze = &mz->mz_chunk[i];
 1483                 if (mze->mze_name[0])
 1484                         //printf("%-32s 0x%jx\n", mze->mze_name, (uintmax_t)mze->mze_value);
 1485                         printf("%s\n", mze->mze_name);
 1486         }
 1487 
 1488         return (0);
 1489 }
 1490 
 1491 /*
 1492  * List a fatzap directory. Assumes that the zap scratch buffer contains
 1493  * the directory header.
 1494  */
 1495 static int
 1496 fzap_list(const spa_t *spa, const dnode_phys_t *dnode)
 1497 {
 1498         int bsize = dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 1499         zap_phys_t zh = *(zap_phys_t *) zap_scratch;
 1500         fat_zap_t z;
 1501         int i, j;
 1502 
 1503         if (zh.zap_magic != ZAP_MAGIC)
 1504                 return (EIO);
 1505 
 1506         z.zap_block_shift = ilog2(bsize);
 1507         z.zap_phys = (zap_phys_t *) zap_scratch;
 1508 
 1509         /*
 1510          * This assumes that the leaf blocks start at block 1. The
 1511          * documentation isn't exactly clear on this.
 1512          */
 1513         zap_leaf_t zl;
 1514         zl.l_bs = z.zap_block_shift;
 1515         for (i = 0; i < zh.zap_num_leafs; i++) {
 1516                 off_t off = (i + 1) << zl.l_bs;
 1517                 char name[256], *p;
 1518                 uint64_t value;
 1519 
 1520                 if (dnode_read(spa, dnode, off, zap_scratch, bsize))
 1521                         return (EIO);
 1522 
 1523                 zl.l_phys = (zap_leaf_phys_t *) zap_scratch;
 1524 
 1525                 for (j = 0; j < ZAP_LEAF_NUMCHUNKS(&zl); j++) {
 1526                         zap_leaf_chunk_t *zc, *nc;
 1527                         int namelen;
 1528 
 1529                         zc = &ZAP_LEAF_CHUNK(&zl, j);
 1530                         if (zc->l_entry.le_type != ZAP_CHUNK_ENTRY)
 1531                                 continue;
 1532                         namelen = zc->l_entry.le_name_numints;
 1533                         if (namelen > sizeof(name))
 1534                                 namelen = sizeof(name);
 1535 
 1536                         /*
 1537                          * Paste the name back together.
 1538                          */
 1539                         nc = &ZAP_LEAF_CHUNK(&zl, zc->l_entry.le_name_chunk);
 1540                         p = name;
 1541                         while (namelen > 0) {
 1542                                 int len;
 1543                                 len = namelen;
 1544                                 if (len > ZAP_LEAF_ARRAY_BYTES)
 1545                                         len = ZAP_LEAF_ARRAY_BYTES;
 1546                                 memcpy(p, nc->l_array.la_array, len);
 1547                                 p += len;
 1548                                 namelen -= len;
 1549                                 nc = &ZAP_LEAF_CHUNK(&zl, nc->l_array.la_next);
 1550                         }
 1551 
 1552                         /*
 1553                          * Assume the first eight bytes of the value are
 1554                          * a uint64_t.
 1555                          */
 1556                         value = fzap_leaf_value(&zl, zc);
 1557 
 1558                         //printf("%s 0x%jx\n", name, (uintmax_t)value);
 1559                         printf("%s\n", name);
 1560                 }
 1561         }
 1562 
 1563         return (0);
 1564 }
 1565 
 1566 /*
 1567  * List a zap directory.
 1568  */
 1569 static int
 1570 zap_list(const spa_t *spa, const dnode_phys_t *dnode)
 1571 {
 1572         uint64_t zap_type;
 1573         size_t size = dnode->dn_datablkszsec * 512;
 1574 
 1575         if (dnode_read(spa, dnode, 0, zap_scratch, size))
 1576                 return (EIO);
 1577 
 1578         zap_type = *(uint64_t *) zap_scratch;
 1579         if (zap_type == ZBT_MICRO)
 1580                 return mzap_list(dnode);
 1581         else
 1582                 return fzap_list(spa, dnode);
 1583 }
 1584 
 1585 static int
 1586 objset_get_dnode(const spa_t *spa, const objset_phys_t *os, uint64_t objnum, dnode_phys_t *dnode)
 1587 {
 1588         off_t offset;
 1589 
 1590         offset = objnum * sizeof(dnode_phys_t);
 1591         return dnode_read(spa, &os->os_meta_dnode, offset,
 1592                 dnode, sizeof(dnode_phys_t));
 1593 }
 1594 
 1595 static int
 1596 mzap_rlookup(const spa_t *spa, const dnode_phys_t *dnode, char *name, uint64_t value)
 1597 {
 1598         const mzap_phys_t *mz;
 1599         const mzap_ent_phys_t *mze;
 1600         size_t size;
 1601         int chunks, i;
 1602 
 1603         /*
 1604          * Microzap objects use exactly one block. Read the whole
 1605          * thing.
 1606          */
 1607         size = dnode->dn_datablkszsec * 512;
 1608 
 1609         mz = (const mzap_phys_t *) zap_scratch;
 1610         chunks = size / MZAP_ENT_LEN - 1;
 1611 
 1612         for (i = 0; i < chunks; i++) {
 1613                 mze = &mz->mz_chunk[i];
 1614                 if (value == mze->mze_value) {
 1615                         strcpy(name, mze->mze_name);
 1616                         return (0);
 1617                 }
 1618         }
 1619 
 1620         return (ENOENT);
 1621 }
 1622 
 1623 static void
 1624 fzap_name_copy(const zap_leaf_t *zl, const zap_leaf_chunk_t *zc, char *name)
 1625 {
 1626         size_t namelen;
 1627         const zap_leaf_chunk_t *nc;
 1628         char *p;
 1629 
 1630         namelen = zc->l_entry.le_name_numints;
 1631 
 1632         nc = &ZAP_LEAF_CHUNK(zl, zc->l_entry.le_name_chunk);
 1633         p = name;
 1634         while (namelen > 0) {
 1635                 size_t len;
 1636                 len = namelen;
 1637                 if (len > ZAP_LEAF_ARRAY_BYTES)
 1638                         len = ZAP_LEAF_ARRAY_BYTES;
 1639                 memcpy(p, nc->l_array.la_array, len);
 1640                 p += len;
 1641                 namelen -= len;
 1642                 nc = &ZAP_LEAF_CHUNK(zl, nc->l_array.la_next);
 1643         }
 1644 
 1645         *p = '\0';
 1646 }
 1647 
 1648 static int
 1649 fzap_rlookup(const spa_t *spa, const dnode_phys_t *dnode, char *name, uint64_t value)
 1650 {
 1651         int bsize = dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 1652         zap_phys_t zh = *(zap_phys_t *) zap_scratch;
 1653         fat_zap_t z;
 1654         int i, j;
 1655 
 1656         if (zh.zap_magic != ZAP_MAGIC)
 1657                 return (EIO);
 1658 
 1659         z.zap_block_shift = ilog2(bsize);
 1660         z.zap_phys = (zap_phys_t *) zap_scratch;
 1661 
 1662         /*
 1663          * This assumes that the leaf blocks start at block 1. The
 1664          * documentation isn't exactly clear on this.
 1665          */
 1666         zap_leaf_t zl;
 1667         zl.l_bs = z.zap_block_shift;
 1668         for (i = 0; i < zh.zap_num_leafs; i++) {
 1669                 off_t off = (i + 1) << zl.l_bs;
 1670 
 1671                 if (dnode_read(spa, dnode, off, zap_scratch, bsize))
 1672                         return (EIO);
 1673 
 1674                 zl.l_phys = (zap_leaf_phys_t *) zap_scratch;
 1675 
 1676                 for (j = 0; j < ZAP_LEAF_NUMCHUNKS(&zl); j++) {
 1677                         zap_leaf_chunk_t *zc;
 1678 
 1679                         zc = &ZAP_LEAF_CHUNK(&zl, j);
 1680                         if (zc->l_entry.le_type != ZAP_CHUNK_ENTRY)
 1681                                 continue;
 1682                         if (zc->l_entry.le_value_intlen != 8 ||
 1683                             zc->l_entry.le_value_numints != 1)
 1684                                 continue;
 1685 
 1686                         if (fzap_leaf_value(&zl, zc) == value) {
 1687                                 fzap_name_copy(&zl, zc, name);
 1688                                 return (0);
 1689                         }
 1690                 }
 1691         }
 1692 
 1693         return (ENOENT);
 1694 }
 1695 
 1696 static int
 1697 zap_rlookup(const spa_t *spa, const dnode_phys_t *dnode, char *name, uint64_t value)
 1698 {
 1699         int rc;
 1700         uint64_t zap_type;
 1701         size_t size = dnode->dn_datablkszsec * 512;
 1702 
 1703         rc = dnode_read(spa, dnode, 0, zap_scratch, size);
 1704         if (rc)
 1705                 return (rc);
 1706 
 1707         zap_type = *(uint64_t *) zap_scratch;
 1708         if (zap_type == ZBT_MICRO)
 1709                 return mzap_rlookup(spa, dnode, name, value);
 1710         else
 1711                 return fzap_rlookup(spa, dnode, name, value);
 1712 }
 1713 
 1714 static int
 1715 zfs_rlookup(const spa_t *spa, uint64_t objnum, char *result)
 1716 {
 1717         char name[256];
 1718         char component[256];
 1719         uint64_t dir_obj, parent_obj, child_dir_zapobj;
 1720         dnode_phys_t child_dir_zap, dataset, dir, parent;
 1721         dsl_dir_phys_t *dd;
 1722         dsl_dataset_phys_t *ds;
 1723         char *p;
 1724         int len;
 1725 
 1726         p = &name[sizeof(name) - 1];
 1727         *p = '\0';
 1728 
 1729         if (objset_get_dnode(spa, &spa->spa_mos, objnum, &dataset)) {
 1730                 printf("ZFS: can't find dataset %ju\n", (uintmax_t)objnum);
 1731                 return (EIO);
 1732         }
 1733         ds = (dsl_dataset_phys_t *)&dataset.dn_bonus;
 1734         dir_obj = ds->ds_dir_obj;
 1735 
 1736         for (;;) {
 1737                 if (objset_get_dnode(spa, &spa->spa_mos, dir_obj, &dir) != 0)
 1738                         return (EIO);
 1739                 dd = (dsl_dir_phys_t *)&dir.dn_bonus;
 1740 
 1741                 /* Actual loop condition. */
 1742                 parent_obj  = dd->dd_parent_obj;
 1743                 if (parent_obj == 0)
 1744                         break;
 1745 
 1746                 if (objset_get_dnode(spa, &spa->spa_mos, parent_obj, &parent) != 0)
 1747                         return (EIO);
 1748                 dd = (dsl_dir_phys_t *)&parent.dn_bonus;
 1749                 child_dir_zapobj = dd->dd_child_dir_zapobj;
 1750                 if (objset_get_dnode(spa, &spa->spa_mos, child_dir_zapobj, &child_dir_zap) != 0)
 1751                         return (EIO);
 1752                 if (zap_rlookup(spa, &child_dir_zap, component, dir_obj) != 0)
 1753                         return (EIO);
 1754 
 1755                 len = strlen(component);
 1756                 p -= len;
 1757                 memcpy(p, component, len);
 1758                 --p;
 1759                 *p = '/';
 1760 
 1761                 /* Actual loop iteration. */
 1762                 dir_obj = parent_obj;
 1763         }
 1764 
 1765         if (*p != '\0')
 1766                 ++p;
 1767         strcpy(result, p);
 1768 
 1769         return (0);
 1770 }
 1771 
 1772 static int
 1773 zfs_lookup_dataset(const spa_t *spa, const char *name, uint64_t *objnum)
 1774 {
 1775         char element[256];
 1776         uint64_t dir_obj, child_dir_zapobj;
 1777         dnode_phys_t child_dir_zap, dir;
 1778         dsl_dir_phys_t *dd;
 1779         const char *p, *q;
 1780 
 1781         if (objset_get_dnode(spa, &spa->spa_mos, DMU_POOL_DIRECTORY_OBJECT, &dir))
 1782                 return (EIO);
 1783         if (zap_lookup(spa, &dir, DMU_POOL_ROOT_DATASET, &dir_obj))
 1784                 return (EIO);
 1785 
 1786         p = name;
 1787         for (;;) {
 1788                 if (objset_get_dnode(spa, &spa->spa_mos, dir_obj, &dir))
 1789                         return (EIO);
 1790                 dd = (dsl_dir_phys_t *)&dir.dn_bonus;
 1791 
 1792                 while (*p == '/')
 1793                         p++;
 1794                 /* Actual loop condition #1. */
 1795                 if (*p == '\0')
 1796                         break;
 1797 
 1798                 q = strchr(p, '/');
 1799                 if (q) {
 1800                         memcpy(element, p, q - p);
 1801                         element[q - p] = '\0';
 1802                         p = q + 1;
 1803                 } else {
 1804                         strcpy(element, p);
 1805                         p += strlen(p);
 1806                 }
 1807 
 1808                 child_dir_zapobj = dd->dd_child_dir_zapobj;
 1809                 if (objset_get_dnode(spa, &spa->spa_mos, child_dir_zapobj, &child_dir_zap) != 0)
 1810                         return (EIO);
 1811 
 1812                 /* Actual loop condition #2. */
 1813                 if (zap_lookup(spa, &child_dir_zap, element, &dir_obj) != 0)
 1814                         return (ENOENT);
 1815         }
 1816 
 1817         *objnum = dd->dd_head_dataset_obj;
 1818         return (0);
 1819 }
 1820 
 1821 #ifndef BOOT2
 1822 static int
 1823 zfs_list_dataset(const spa_t *spa, uint64_t objnum/*, int pos, char *entry*/)
 1824 {
 1825         uint64_t dir_obj, child_dir_zapobj;
 1826         dnode_phys_t child_dir_zap, dir, dataset;
 1827         dsl_dataset_phys_t *ds;
 1828         dsl_dir_phys_t *dd;
 1829 
 1830         if (objset_get_dnode(spa, &spa->spa_mos, objnum, &dataset)) {
 1831                 printf("ZFS: can't find dataset %ju\n", (uintmax_t)objnum);
 1832                 return (EIO);
 1833         }
 1834         ds = (dsl_dataset_phys_t *) &dataset.dn_bonus;
 1835         dir_obj = ds->ds_dir_obj;
 1836 
 1837         if (objset_get_dnode(spa, &spa->spa_mos, dir_obj, &dir)) {
 1838                 printf("ZFS: can't find dirobj %ju\n", (uintmax_t)dir_obj);
 1839                 return (EIO);
 1840         }
 1841         dd = (dsl_dir_phys_t *)&dir.dn_bonus;
 1842 
 1843         child_dir_zapobj = dd->dd_child_dir_zapobj;
 1844         if (objset_get_dnode(spa, &spa->spa_mos, child_dir_zapobj, &child_dir_zap) != 0) {
 1845                 printf("ZFS: can't find child zap %ju\n", (uintmax_t)dir_obj);
 1846                 return (EIO);
 1847         }
 1848 
 1849         return (zap_list(spa, &child_dir_zap) != 0);
 1850 }
 1851 #endif
 1852 
 1853 /*
 1854  * Find the object set given the object number of its dataset object
 1855  * and return its details in *objset
 1856  */
 1857 static int
 1858 zfs_mount_dataset(const spa_t *spa, uint64_t objnum, objset_phys_t *objset)
 1859 {
 1860         dnode_phys_t dataset;
 1861         dsl_dataset_phys_t *ds;
 1862 
 1863         if (objset_get_dnode(spa, &spa->spa_mos, objnum, &dataset)) {
 1864                 printf("ZFS: can't find dataset %ju\n", (uintmax_t)objnum);
 1865                 return (EIO);
 1866         }
 1867 
 1868         ds = (dsl_dataset_phys_t *) &dataset.dn_bonus;
 1869         if (zio_read(spa, &ds->ds_bp, objset)) {
 1870                 printf("ZFS: can't read object set for dataset %ju\n",
 1871                     (uintmax_t)objnum);
 1872                 return (EIO);
 1873         }
 1874 
 1875         return (0);
 1876 }
 1877 
 1878 /*
 1879  * Find the object set pointed to by the BOOTFS property or the root
 1880  * dataset if there is none and return its details in *objset
 1881  */
 1882 static int
 1883 zfs_get_root(const spa_t *spa, uint64_t *objid)
 1884 {
 1885         dnode_phys_t dir, propdir;
 1886         uint64_t props, bootfs, root;
 1887 
 1888         *objid = 0;
 1889 
 1890         /*
 1891          * Start with the MOS directory object.
 1892          */
 1893         if (objset_get_dnode(spa, &spa->spa_mos, DMU_POOL_DIRECTORY_OBJECT, &dir)) {
 1894                 printf("ZFS: can't read MOS object directory\n");
 1895                 return (EIO);
 1896         }
 1897 
 1898         /*
 1899          * Lookup the pool_props and see if we can find a bootfs.
 1900          */
 1901         if (zap_lookup(spa, &dir, DMU_POOL_PROPS, &props) == 0
 1902              && objset_get_dnode(spa, &spa->spa_mos, props, &propdir) == 0
 1903              && zap_lookup(spa, &propdir, "bootfs", &bootfs) == 0
 1904              && bootfs != 0)
 1905         {
 1906                 *objid = bootfs;
 1907                 return (0);
 1908         }
 1909         /*
 1910          * Lookup the root dataset directory
 1911          */
 1912         if (zap_lookup(spa, &dir, DMU_POOL_ROOT_DATASET, &root)
 1913             || objset_get_dnode(spa, &spa->spa_mos, root, &dir)) {
 1914                 printf("ZFS: can't find root dsl_dir\n");
 1915                 return (EIO);
 1916         }
 1917 
 1918         /*
 1919          * Use the information from the dataset directory's bonus buffer
 1920          * to find the dataset object and from that the object set itself.
 1921          */
 1922         dsl_dir_phys_t *dd = (dsl_dir_phys_t *) &dir.dn_bonus;
 1923         *objid = dd->dd_head_dataset_obj;
 1924         return (0);
 1925 }
 1926 
 1927 static int
 1928 zfs_mount(const spa_t *spa, uint64_t rootobj, struct zfsmount *mount)
 1929 {
 1930 
 1931         mount->spa = spa;
 1932 
 1933         /*
 1934          * Find the root object set if not explicitly provided
 1935          */
 1936         if (rootobj == 0 && zfs_get_root(spa, &rootobj)) {
 1937                 printf("ZFS: can't find root filesystem\n");
 1938                 return (EIO);
 1939         }
 1940 
 1941         if (zfs_mount_dataset(spa, rootobj, &mount->objset)) {
 1942                 printf("ZFS: can't open root filesystem\n");
 1943                 return (EIO);
 1944         }
 1945 
 1946         mount->rootobj = rootobj;
 1947 
 1948         return (0);
 1949 }
 1950 
 1951 static int
 1952 zfs_spa_init(spa_t *spa)
 1953 {
 1954 
 1955         if (zio_read(spa, &spa->spa_uberblock.ub_rootbp, &spa->spa_mos)) {
 1956                 printf("ZFS: can't read MOS of pool %s\n", spa->spa_name);
 1957                 return (EIO);
 1958         }
 1959         if (spa->spa_mos.os_type != DMU_OST_META) {
 1960                 printf("ZFS: corrupted MOS of pool %s\n", spa->spa_name);
 1961                 return (EIO);
 1962         }
 1963         return (0);
 1964 }
 1965 
 1966 static int
 1967 zfs_dnode_stat(const spa_t *spa, dnode_phys_t *dn, struct stat *sb)
 1968 {
 1969 
 1970         if (dn->dn_bonustype != DMU_OT_SA) {
 1971                 znode_phys_t *zp = (znode_phys_t *)dn->dn_bonus;
 1972 
 1973                 sb->st_mode = zp->zp_mode;
 1974                 sb->st_uid = zp->zp_uid;
 1975                 sb->st_gid = zp->zp_gid;
 1976                 sb->st_size = zp->zp_size;
 1977         } else {
 1978                 sa_hdr_phys_t *sahdrp;
 1979                 int hdrsize;
 1980                 size_t size = 0;
 1981                 void *buf = NULL;
 1982 
 1983                 if (dn->dn_bonuslen != 0)
 1984                         sahdrp = (sa_hdr_phys_t *)DN_BONUS(dn);
 1985                 else {
 1986                         if ((dn->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0) {
 1987                                 blkptr_t *bp = &dn->dn_spill;
 1988                                 int error;
 1989 
 1990                                 size = BP_GET_LSIZE(bp);
 1991                                 buf = zfs_alloc(size);
 1992                                 error = zio_read(spa, bp, buf);
 1993                                 if (error != 0) {
 1994                                         zfs_free(buf, size);
 1995                                         return (error);
 1996                                 }
 1997                                 sahdrp = buf;
 1998                         } else {
 1999                                 return (EIO);
 2000                         }
 2001                 }
 2002                 hdrsize = SA_HDR_SIZE(sahdrp);
 2003                 sb->st_mode = *(uint64_t *)((char *)sahdrp + hdrsize +
 2004                     SA_MODE_OFFSET);
 2005                 sb->st_uid = *(uint64_t *)((char *)sahdrp + hdrsize +
 2006                     SA_UID_OFFSET);
 2007                 sb->st_gid = *(uint64_t *)((char *)sahdrp + hdrsize +
 2008                     SA_GID_OFFSET);
 2009                 sb->st_size = *(uint64_t *)((char *)sahdrp + hdrsize +
 2010                     SA_SIZE_OFFSET);
 2011                 if (buf != NULL)
 2012                         zfs_free(buf, size);
 2013         }
 2014 
 2015         return (0);
 2016 }
 2017 
 2018 /*
 2019  * Lookup a file and return its dnode.
 2020  */
 2021 static int
 2022 zfs_lookup(const struct zfsmount *mount, const char *upath, dnode_phys_t *dnode)
 2023 {
 2024         int rc;
 2025         uint64_t objnum, rootnum, parentnum;
 2026         const spa_t *spa;
 2027         dnode_phys_t dn;
 2028         const char *p, *q;
 2029         char element[256];
 2030         char path[1024];
 2031         int symlinks_followed = 0;
 2032         struct stat sb;
 2033 
 2034         spa = mount->spa;
 2035         if (mount->objset.os_type != DMU_OST_ZFS) {
 2036                 printf("ZFS: unexpected object set type %ju\n",
 2037                     (uintmax_t)mount->objset.os_type);
 2038                 return (EIO);
 2039         }
 2040 
 2041         /*
 2042          * Get the root directory dnode.
 2043          */
 2044         rc = objset_get_dnode(spa, &mount->objset, MASTER_NODE_OBJ, &dn);
 2045         if (rc)
 2046                 return (rc);
 2047 
 2048         rc = zap_lookup(spa, &dn, ZFS_ROOT_OBJ, &rootnum);
 2049         if (rc)
 2050                 return (rc);
 2051 
 2052         rc = objset_get_dnode(spa, &mount->objset, rootnum, &dn);
 2053         if (rc)
 2054                 return (rc);
 2055 
 2056         objnum = rootnum;
 2057         p = upath;
 2058         while (p && *p) {
 2059                 while (*p == '/')
 2060                         p++;
 2061                 if (!*p)
 2062                         break;
 2063                 q = strchr(p, '/');
 2064                 if (q) {
 2065                         memcpy(element, p, q - p);
 2066                         element[q - p] = 0;
 2067                         p = q;
 2068                 } else {
 2069                         strcpy(element, p);
 2070                         p = 0;
 2071                 }
 2072 
 2073                 rc = zfs_dnode_stat(spa, &dn, &sb);
 2074                 if (rc)
 2075                         return (rc);
 2076                 if (!S_ISDIR(sb.st_mode))
 2077                         return (ENOTDIR);
 2078 
 2079                 parentnum = objnum;
 2080                 rc = zap_lookup(spa, &dn, element, &objnum);
 2081                 if (rc)
 2082                         return (rc);
 2083                 objnum = ZFS_DIRENT_OBJ(objnum);
 2084 
 2085                 rc = objset_get_dnode(spa, &mount->objset, objnum, &dn);
 2086                 if (rc)
 2087                         return (rc);
 2088 
 2089                 /*
 2090                  * Check for symlink.
 2091                  */
 2092                 rc = zfs_dnode_stat(spa, &dn, &sb);
 2093                 if (rc)
 2094                         return (rc);
 2095                 if (S_ISLNK(sb.st_mode)) {
 2096                         if (symlinks_followed > 10)
 2097                                 return (EMLINK);
 2098                         symlinks_followed++;
 2099 
 2100                         /*
 2101                          * Read the link value and copy the tail of our
 2102                          * current path onto the end.
 2103                          */
 2104                         if (p)
 2105                                 strcpy(&path[sb.st_size], p);
 2106                         else
 2107                                 path[sb.st_size] = 0;
 2108                         if (sb.st_size + sizeof(znode_phys_t) <= dn.dn_bonuslen) {
 2109                                 memcpy(path, &dn.dn_bonus[sizeof(znode_phys_t)],
 2110                                         sb.st_size);
 2111                         } else {
 2112                                 rc = dnode_read(spa, &dn, 0, path, sb.st_size);
 2113                                 if (rc)
 2114                                         return (rc);
 2115                         }
 2116 
 2117                         /*
 2118                          * Restart with the new path, starting either at
 2119                          * the root or at the parent depending whether or
 2120                          * not the link is relative.
 2121                          */
 2122                         p = path;
 2123                         if (*p == '/')
 2124                                 objnum = rootnum;
 2125                         else
 2126                                 objnum = parentnum;
 2127                         objset_get_dnode(spa, &mount->objset, objnum, &dn);
 2128                 }
 2129         }
 2130 
 2131         *dnode = dn;
 2132         return (0);
 2133 }
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FreeBSD/Linux Kernel Cross Reference sys/boot/zfs/zfsimpl.c

FreeBSD/Linux Kernel Cross Reference
sys/boot/zfs/zfsimpl.c
