zfs/zcmd/zinject/translate.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "@(#)translate.c        1.3     07/11/09 SMI"
  27
  28 #include <libzfs.h>
  29
  30 #undef verify   /* both libzfs.h and zfs_context.h want to define this */
  31
  32 #include <sys/zfs_context.h>
  33
  34 #include <errno.h>
  35 #include <fcntl.h>
  36 #include <stdarg.h>
  37 #include <stddef.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <strings.h>
  41 #include <sys/file.h>
  42 #include <sys/mntent.h>
  43 #include <sys/mnttab.h>
  44 #include <sys/param.h>
  45 #include <sys/stat.h>
  46
  47 #include <sys/dmu.h>
  48 #include <sys/dmu_objset.h>
  49 #include <sys/dnode.h>
  50
  51 #include <sys/mkdev.h>
  52
  53 #include "zinject.h"
  54
  55 extern void kernel_init(int);
  56 extern void kernel_fini(void);
  57
  58 static int debug;
  59
  60 static void
  61 ziprintf(const char *fmt, ...)
  62 {
  63         va_list ap;
  64
  65         if (!debug)
  66                 return;
  67
  68         va_start(ap, fmt);
  69         (void) vprintf(fmt, ap);
  70         va_end(ap);
  71 }
  72
  73 /*
  74  * Given a full path to a file, translate into a dataset name and a relative
  75  * path within the dataset.  'dataset' must be at least MAXNAMELEN characters,
  76  * and 'relpath' must be at least MAXPATHLEN characters.  We also pass a stat64
  77  * buffer, which we need later to get the object ID.
  78  */
  79 static int
  80 parse_pathname(const char *fullpath, char *dataset, char *relpath,
  81     struct stat64 *statbuf)
  82 {
  83         struct extmnttab mp;
  84         FILE *fp;
  85         int match;
  86         const char *rel;
  87
  88         if (fullpath[0] != '/') {
  89                 (void) fprintf(stderr, "invalid object '%s': must be full "
  90                     "path\n", fullpath);
  91                 usage();
  92                 return (-1);
  93         }
  94
  95         if (strlen(fullpath) >= MAXPATHLEN) {
  96                 (void) fprintf(stderr, "invalid object; pathname too long\n");
  97                 return (-1);
  98         }
  99
 100         if (stat64(fullpath, statbuf) != 0) {
 101                 (void) fprintf(stderr, "cannot open '%s': %s\n",
 102                     fullpath, strerror(errno));
 103                 return (-1);
 104         }
 105
 106         if ((fp = fopen(MNTTAB, "r")) == NULL) {
 107                 (void) fprintf(stderr, "cannot open /etc/mnttab\n");
 108                 return (-1);
 109         }
 110
 111         match = 0;
 112         while (getextmntent(fp, &mp, sizeof (mp)) == 0) {
 113                 if (makedev(mp.mnt_major, mp.mnt_minor) == statbuf->st_dev) {
 114                         match = 1;
 115                         break;
 116                 }
 117         }
 118
 119         if (!match) {
 120                 (void) fprintf(stderr, "cannot find mountpoint for '%s'\n",
 121                     fullpath);
 122                 return (-1);
 123         }
 124
 125         if (strcmp(mp.mnt_fstype, MNTTYPE_ZFS) != 0) {
 126                 (void) fprintf(stderr, "invalid path '%s': not a ZFS "
 127                     "filesystem\n", fullpath);
 128                 return (-1);
 129         }
 130
 131         if (strncmp(fullpath, mp.mnt_mountp, strlen(mp.mnt_mountp)) != 0) {
 132                 (void) fprintf(stderr, "invalid path '%s': mountpoint "
 133                     "doesn't match path\n", fullpath);
 134                 return (-1);
 135         }
 136
 137         (void) strcpy(dataset, mp.mnt_special);
 138
 139         rel = fullpath + strlen(mp.mnt_mountp);
 140         if (rel[0] == '/')
 141                 rel++;
 142         (void) strcpy(relpath, rel);
 143
 144         return (0);
 145 }
 146
 147 /*
 148  * Convert from a (dataset, path) pair into a (objset, object) pair.  Note that
 149  * we grab the object number from the inode number, since looking this up via
 150  * libzpool is a real pain.
 151  */
 152 /* ARGSUSED */
 153 static int
 154 object_from_path(const char *dataset, const char *path, struct stat64 *statbuf,
 155     zinject_record_t *record)
 156 {
 157         objset_t *os;
 158         int err;
 159
 160         /*
 161          * Before doing any libzpool operations, call sync() to ensure that the
 162          * on-disk state is consistent with the in-core state.
 163          */
 164         sync();
 165
 166         if ((err = dmu_objset_open(dataset, DMU_OST_ZFS,
 167             DS_MODE_STANDARD | DS_MODE_READONLY, &os)) != 0) {
 168                 (void) fprintf(stderr, "cannot open dataset '%s': %s\n",
 169                     dataset, strerror(err));
 170                 return (-1);
 171         }
 172
 173         record->zi_objset = dmu_objset_id(os);
 174         record->zi_object = statbuf->st_ino;
 175
 176         dmu_objset_close(os);
 177
 178         return (0);
 179 }
 180
 181 /*
 182  * Calculate the real range based on the type, level, and range given.
 183  */
 184 static int
 185 calculate_range(const char *dataset, err_type_t type, int level, char *range,
 186     zinject_record_t *record)
 187 {
 188         objset_t *os = NULL;
 189         dnode_t *dn = NULL;
 190         int err;
 191         int ret = -1;
 192
 193         /*
 194          * Determine the numeric range from the string.
 195          */
 196         if (range == NULL) {
 197                 /*
 198                  * If range is unspecified, set the range to [0,-1], which
 199                  * indicates that the whole object should be treated as an
 200                  * error.
 201                  */
 202                 record->zi_start = 0;
 203                 record->zi_end = -1ULL;
 204         } else {
 205                 char *end;
 206
 207                 /* XXX add support for suffixes */
 208                 record->zi_start = strtoull(range, &end, 10);
 209
 210
 211                 if (*end == '\0')
 212                         record->zi_end = record->zi_start + 1;
 213                 else if (*end == ',')
 214                         record->zi_end = strtoull(end + 1, &end, 10);
 215
 216                 if (*end != '\0') {
 217                         (void) fprintf(stderr, "invalid range '%s': must be "
 218                             "a numeric range of the form 'start[,end]'\n",
 219                             range);
 220                         goto out;
 221                 }
 222         }
 223
 224         switch (type) {
 225         case TYPE_DATA:
 226                 break;
 227
 228         case TYPE_DNODE:
 229                 /*
 230                  * If this is a request to inject faults into the dnode, then we
 231                  * must translate the current (objset,object) pair into an
 232                  * offset within the metadnode for the objset.  Specifying any
 233                  * kind of range with type 'dnode' is illegal.
 234                  */
 235                 if (range != NULL) {
 236                         (void) fprintf(stderr, "range cannot be specified when "
 237                             "type is 'dnode'\n");
 238                         goto out;
 239                 }
 240
 241                 record->zi_start = record->zi_object * sizeof (dnode_phys_t);
 242                 record->zi_end = record->zi_start + sizeof (dnode_phys_t);
 243                 record->zi_object = 0;
 244                 break;
 245         }
 246
 247         /*
 248          * Get the dnode associated with object, so we can calculate the block
 249          * size.
 250          */
 251         if ((err = dmu_objset_open(dataset, DMU_OST_ANY,
 252             DS_MODE_STANDARD | DS_MODE_READONLY, &os)) != 0) {
 253                 (void) fprintf(stderr, "cannot open dataset '%s': %s\n",
 254                     dataset, strerror(err));
 255                 goto out;
 256         }
 257
 258         if (record->zi_object == 0) {
 259                 dn = os->os->os_meta_dnode;
 260         } else {
 261                 err = dnode_hold(os->os, record->zi_object, FTAG, &dn);
 262                 if (err != 0) {
 263                         (void) fprintf(stderr, "failed to hold dnode "
 264                             "for object %llu\n",
 265                             (u_longlong_t)record->zi_object);
 266                         goto out;
 267                 }
 268         }
 269
 270
 271         ziprintf("data shift: %d\n", (int)dn->dn_datablkshift);
 272         ziprintf(" ind shift: %d\n", (int)dn->dn_indblkshift);
 273
 274         /*
 275          * Translate range into block IDs.
 276          */
 277         if (record->zi_start != 0 || record->zi_end != -1ULL) {
 278                 record->zi_start >>= dn->dn_datablkshift;
 279                 record->zi_end >>= dn->dn_datablkshift;
 280         }
 281
 282         /*
 283          * Check level, and then translate level 0 blkids into ranges
 284          * appropriate for level of indirection.
 285          */
 286         record->zi_level = level;
 287         if (level > 0) {
 288                 ziprintf("level 0 blkid range: [%llu, %llu]\n",
 289                     record->zi_start, record->zi_end);
 290
 291                 if (level >= dn->dn_nlevels) {
 292                         (void) fprintf(stderr, "level %d exceeds max level "
 293                             "of object (%d)\n", level, dn->dn_nlevels - 1);
 294                         goto out;
 295                 }
 296
 297                 if (record->zi_start != 0 || record->zi_end != 0) {
 298                         int shift = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
 299
 300                         for (; level > 0; level--) {
 301                                 record->zi_start >>= shift;
 302                                 record->zi_end >>= shift;
 303                         }
 304                 }
 305         }
 306
 307         ret = 0;
 308 out:
 309         if (dn) {
 310                 if (dn != os->os->os_meta_dnode)
 311                         dnode_rele(dn, FTAG);
 312         }
 313         if (os)
 314                 dmu_objset_close(os);
 315
 316         return (ret);
 317 }
 318
 319 int
 320 translate_record(err_type_t type, const char *object, const char *range,
 321     int level, zinject_record_t *record, char *poolname, char *dataset)
 322 {
 323         char path[MAXPATHLEN];
 324         char *slash;
 325         struct stat64 statbuf;
 326         int ret = -1;
 327
 328         kernel_init(FREAD);
 329
 330         debug = (getenv("ZINJECT_DEBUG") != NULL);
 331
 332         ziprintf("translating: %s\n", object);
 333
 334         if (MOS_TYPE(type)) {
 335                 /*
 336                  * MOS objects are treated specially.
 337                  */
 338                 switch (type) {
 339                 case TYPE_MOS:
 340                         record->zi_type = 0;
 341                         break;
 342                 case TYPE_MOSDIR:
 343                         record->zi_type = DMU_OT_OBJECT_DIRECTORY;
 344                         break;
 345                 case TYPE_METASLAB:
 346                         record->zi_type = DMU_OT_OBJECT_ARRAY;
 347                         break;
 348                 case TYPE_CONFIG:
 349                         record->zi_type = DMU_OT_PACKED_NVLIST;
 350                         break;
 351                 case TYPE_BPLIST:
 352                         record->zi_type = DMU_OT_BPLIST;
 353                         break;
 354                 case TYPE_SPACEMAP:
 355                         record->zi_type = DMU_OT_SPACE_MAP;
 356                         break;
 357                 case TYPE_ERRLOG:
 358                         record->zi_type = DMU_OT_ERROR_LOG;
 359                         break;
 360                 }
 361
 362                 dataset[0] = '\0';
 363                 (void) strcpy(poolname, object);
 364                 return (0);
 365         }
 366
 367         /*
 368          * Convert a full path into a (dataset, file) pair.
 369          */
 370         if (parse_pathname(object, dataset, path, &statbuf) != 0)
 371                 goto err;
 372
 373         ziprintf("   dataset: %s\n", dataset);
 374         ziprintf("      path: %s\n", path);
 375
 376         /*
 377          * Convert (dataset, file) into (objset, object)
 378          */
 379         if (object_from_path(dataset, path, &statbuf, record) != 0)
 380                 goto err;
 381
 382         ziprintf("raw objset: %llu\n", record->zi_objset);
 383         ziprintf("raw object: %llu\n", record->zi_object);
 384
 385         /*
 386          * For the given object, calculate the real (type, level, range)
 387          */
 388         if (calculate_range(dataset, type, level, (char *)range, record) != 0)
 389                 goto err;
 390
 391         ziprintf("    objset: %llu\n", record->zi_objset);
 392         ziprintf("    object: %llu\n", record->zi_object);
 393         if (record->zi_start == 0 &&
 394             record->zi_end == -1ULL)
 395                 ziprintf("     range: all\n");
 396         else
 397                 ziprintf("     range: [%llu, %llu]\n", record->zi_start,
 398                     record->zi_end);
 399
 400         /*
 401          * Copy the pool name
 402          */
 403         (void) strcpy(poolname, dataset);
 404         if ((slash = strchr(poolname, '/')) != NULL)
 405                 *slash = '\0';
 406
 407         ret = 0;
 408
 409 err:
 410         kernel_fini();
 411         return (ret);
 412 }
 413
 414 int
 415 translate_raw(const char *str, zinject_record_t *record)
 416 {
 417         /*
 418          * A raw bookmark of the form objset:object:level:blkid, where each
 419          * number is a hexidecimal value.
 420          */
 421         if (sscanf(str, "%llx:%llx:%x:%llx", (u_longlong_t *)&record->zi_objset,
 422             (u_longlong_t *)&record->zi_object, &record->zi_level,
 423             (u_longlong_t *)&record->zi_start) != 4) {
 424                 (void) fprintf(stderr, "bad raw spec '%s': must be of the form "
 425                     "'objset:object:level:blkid'\n", str);
 426                 return (-1);
 427         }
 428
 429         record->zi_end = record->zi_start;
 430
 431         return (0);
 432 }
 433
 434 int
 435 translate_device(const char *pool, const char *device, zinject_record_t *record)
 436 {
 437         char *end;
 438         zpool_handle_t *zhp;
 439         nvlist_t *tgt;
 440         boolean_t isspare, iscache;
 441
 442         /*
 443          * Given a device name or GUID, create an appropriate injection record
 444          * with zi_guid set.
 445          */
 446         if ((zhp = zpool_open(g_zfs, pool)) == NULL)
 447                 return (-1);
 448
 449         record->zi_guid = strtoull(device, &end, 16);
 450         if (record->zi_guid == 0 || *end != '\0') {
 451                 tgt = zpool_find_vdev(zhp, device, &isspare, &iscache);
 452
 453                 if (tgt == NULL) {
 454                         (void) fprintf(stderr, "cannot find device '%s' in "
 455                             "pool '%s'\n", device, pool);
 456                         return (-1);
 457                 }
 458
 459                 verify(nvlist_lookup_uint64(tgt, ZPOOL_CONFIG_GUID,
 460                     &record->zi_guid) == 0);
 461         }
 462
 463         return (0);
 464 }