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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2013 by Delphix. All rights reserved.
  24  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
  25  * Copyright (c) 2013 Joyent, Inc.  All rights reserved.
  26  */
  27 
  28 #include <sys/zfs_context.h>
  29 #include <sys/spa_impl.h>
  30 #include <sys/refcount.h>
  31 #include <sys/vdev_disk.h>
  32 #include <sys/vdev_impl.h>
  33 #include <sys/fs/zfs.h>
  34 #include <sys/zio.h>
  35 #include <sys/sunldi.h>
  36 #include <sys/efi_partition.h>
  37 #include <sys/fm/fs/zfs.h>
  38 
  39 /*
  40  * Virtual device vector for disks.
  41  */
  42 
  43 extern ldi_ident_t zfs_li;
  44 
  45 static void vdev_disk_close(vdev_t *);
  46 
  47 typedef struct vdev_disk_ldi_cb {
  48         list_node_t             lcb_next;
  49         ldi_callback_id_t       lcb_id;
  50 } vdev_disk_ldi_cb_t;
  51 
  52 static void
  53 vdev_disk_alloc(vdev_t *vd)
  54 {
  55         vdev_disk_t *dvd;
  56 
  57         dvd = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP);
  58         /*
  59          * Create the LDI event callback list.
  60          */
  61         list_create(&dvd->vd_ldi_cbs, sizeof (vdev_disk_ldi_cb_t),
  62             offsetof(vdev_disk_ldi_cb_t, lcb_next));
  63 }
  64 
  65 static void
  66 vdev_disk_free(vdev_t *vd)
  67 {
  68         vdev_disk_t *dvd = vd->vdev_tsd;
  69         vdev_disk_ldi_cb_t *lcb;
  70 
  71         if (dvd == NULL)
  72                 return;
  73 
  74         /*
  75          * We have already closed the LDI handle. Clean up the LDI event
  76          * callbacks and free vd->vdev_tsd.
  77          */
  78         while ((lcb = list_head(&dvd->vd_ldi_cbs)) != NULL) {
  79                 list_remove(&dvd->vd_ldi_cbs, lcb);
  80                 (void) ldi_ev_remove_callbacks(lcb->lcb_id);
  81                 kmem_free(lcb, sizeof (vdev_disk_ldi_cb_t));
  82         }
  83         list_destroy(&dvd->vd_ldi_cbs);
  84         kmem_free(dvd, sizeof (vdev_disk_t));
  85         vd->vdev_tsd = NULL;
  86 }
  87 
  88 /* ARGSUSED */
  89 static int
  90 vdev_disk_off_notify(ldi_handle_t lh, ldi_ev_cookie_t ecookie, void *arg,
  91     void *ev_data)
  92 {
  93         vdev_t *vd = (vdev_t *)arg;
  94         vdev_disk_t *dvd = vd->vdev_tsd;
  95 
  96         /*
  97          * Ignore events other than offline.
  98          */
  99         if (strcmp(ldi_ev_get_type(ecookie), LDI_EV_OFFLINE) != 0)
 100                 return (LDI_EV_SUCCESS);
 101 
 102         /*
 103          * All LDI handles must be closed for the state change to succeed, so
 104          * call on vdev_disk_close() to do this.
 105          *
 106          * We inform vdev_disk_close that it is being called from offline
 107          * notify context so it will defer cleanup of LDI event callbacks and
 108          * freeing of vd->vdev_tsd to the offline finalize or a reopen.
 109          */
 110         dvd->vd_ldi_offline = B_TRUE;
 111         vdev_disk_close(vd);
 112 
 113         /*
 114          * Now that the device is closed, request that the spa_async_thread
 115          * mark the device as REMOVED and notify FMA of the removal.
 116          */
 117         zfs_post_remove(vd->vdev_spa, vd);
 118         vd->vdev_remove_wanted = B_TRUE;
 119         spa_async_request(vd->vdev_spa, SPA_ASYNC_REMOVE);
 120 
 121         return (LDI_EV_SUCCESS);
 122 }
 123 
 124 /* ARGSUSED */
 125 static void
 126 vdev_disk_off_finalize(ldi_handle_t lh, ldi_ev_cookie_t ecookie,
 127     int ldi_result, void *arg, void *ev_data)
 128 {
 129         vdev_t *vd = (vdev_t *)arg;
 130 
 131         /*
 132          * Ignore events other than offline.
 133          */
 134         if (strcmp(ldi_ev_get_type(ecookie), LDI_EV_OFFLINE) != 0)
 135                 return;
 136 
 137         /*
 138          * We have already closed the LDI handle in notify.
 139          * Clean up the LDI event callbacks and free vd->vdev_tsd.
 140          */
 141         vdev_disk_free(vd);
 142 
 143         /*
 144          * Request that the vdev be reopened if the offline state change was
 145          * unsuccessful.
 146          */
 147         if (ldi_result != LDI_EV_SUCCESS) {
 148                 vd->vdev_probe_wanted = B_TRUE;
 149                 spa_async_request(vd->vdev_spa, SPA_ASYNC_PROBE);
 150         }
 151 }
 152 
 153 static ldi_ev_callback_t vdev_disk_off_callb = {
 154         .cb_vers = LDI_EV_CB_VERS,
 155         .cb_notify = vdev_disk_off_notify,
 156         .cb_finalize = vdev_disk_off_finalize
 157 };
 158 
 159 /* ARGSUSED */
 160 static void
 161 vdev_disk_dgrd_finalize(ldi_handle_t lh, ldi_ev_cookie_t ecookie,
 162     int ldi_result, void *arg, void *ev_data)
 163 {
 164         vdev_t *vd = (vdev_t *)arg;
 165 
 166         /*
 167          * Ignore events other than degrade.
 168          */
 169         if (strcmp(ldi_ev_get_type(ecookie), LDI_EV_DEGRADE) != 0)
 170                 return;
 171 
 172         /*
 173          * Degrade events always succeed. Mark the vdev as degraded.
 174          * This status is purely informative for the user.
 175          */
 176         (void) vdev_degrade(vd->vdev_spa, vd->vdev_guid, 0);
 177 }
 178 
 179 static ldi_ev_callback_t vdev_disk_dgrd_callb = {
 180         .cb_vers = LDI_EV_CB_VERS,
 181         .cb_notify = NULL,
 182         .cb_finalize = vdev_disk_dgrd_finalize
 183 };
 184 
 185 static void
 186 vdev_disk_hold(vdev_t *vd)
 187 {
 188         ddi_devid_t devid;
 189         char *minor;
 190 
 191         ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER));
 192 
 193         /*
 194          * We must have a pathname, and it must be absolute.
 195          */
 196         if (vd->vdev_path == NULL || vd->vdev_path[0] != '/')
 197                 return;
 198 
 199         /*
 200          * Only prefetch path and devid info if the device has
 201          * never been opened.
 202          */
 203         if (vd->vdev_tsd != NULL)
 204                 return;
 205 
 206         if (vd->vdev_wholedisk == -1ULL) {
 207                 size_t len = strlen(vd->vdev_path) + 3;
 208                 char *buf = kmem_alloc(len, KM_SLEEP);
 209 
 210                 (void) snprintf(buf, len, "%ss0", vd->vdev_path);
 211 
 212                 (void) ldi_vp_from_name(buf, &vd->vdev_name_vp);
 213                 kmem_free(buf, len);
 214         }
 215 
 216         if (vd->vdev_name_vp == NULL)
 217                 (void) ldi_vp_from_name(vd->vdev_path, &vd->vdev_name_vp);
 218 
 219         if (vd->vdev_devid != NULL &&
 220             ddi_devid_str_decode(vd->vdev_devid, &devid, &minor) == 0) {
 221                 (void) ldi_vp_from_devid(devid, minor, &vd->vdev_devid_vp);
 222                 ddi_devid_str_free(minor);
 223                 ddi_devid_free(devid);
 224         }
 225 }
 226 
 227 static void
 228 vdev_disk_rele(vdev_t *vd)
 229 {
 230         ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER));
 231 
 232         if (vd->vdev_name_vp) {
 233                 VN_RELE_ASYNC(vd->vdev_name_vp,
 234                     dsl_pool_vnrele_taskq(vd->vdev_spa->spa_dsl_pool));
 235                 vd->vdev_name_vp = NULL;
 236         }
 237         if (vd->vdev_devid_vp) {
 238                 VN_RELE_ASYNC(vd->vdev_devid_vp,
 239                     dsl_pool_vnrele_taskq(vd->vdev_spa->spa_dsl_pool));
 240                 vd->vdev_devid_vp = NULL;
 241         }
 242 }
 243 
 244 static uint64_t
 245 vdev_disk_get_space(vdev_t *vd, uint64_t capacity, uint_t blksz)
 246 {
 247         ASSERT(vd->vdev_wholedisk);
 248 
 249         vdev_disk_t *dvd = vd->vdev_tsd;
 250         dk_efi_t dk_ioc;
 251         efi_gpt_t *efi;
 252         uint64_t avail_space = 0;
 253         int efisize = EFI_LABEL_SIZE * 2;
 254 
 255         dk_ioc.dki_data = kmem_alloc(efisize, KM_SLEEP);
 256         dk_ioc.dki_lba = 1;
 257         dk_ioc.dki_length = efisize;
 258         dk_ioc.dki_data_64 = (uint64_t)(uintptr_t)dk_ioc.dki_data;
 259         efi = dk_ioc.dki_data;
 260 
 261         if (ldi_ioctl(dvd->vd_lh, DKIOCGETEFI, (intptr_t)&dk_ioc,
 262             FKIOCTL, kcred, NULL) == 0) {
 263                 uint64_t efi_altern_lba = LE_64(efi->efi_gpt_AlternateLBA);
 264 
 265                 zfs_dbgmsg("vdev %s, capacity %llu, altern lba %llu",
 266                     vd->vdev_path, capacity, efi_altern_lba);
 267                 if (capacity > efi_altern_lba)
 268                         avail_space = (capacity - efi_altern_lba) * blksz;
 269         }
 270         kmem_free(dk_ioc.dki_data, efisize);
 271         return (avail_space);
 272 }
 273 
 274 /*
 275  * We want to be loud in DEBUG kernels when DKIOCGMEDIAINFOEXT fails, or when
 276  * even a fallback to DKIOCGMEDIAINFO fails.
 277  */
 278 #ifdef DEBUG
 279 #define VDEV_DEBUG(...) cmn_err(CE_NOTE, __VA_ARGS__)
 280 #else
 281 #define VDEV_DEBUG(...) /* Nothing... */
 282 #endif
 283 
 284 static int
 285 vdev_disk_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
 286     uint64_t *ashift)
 287 {
 288         spa_t *spa = vd->vdev_spa;
 289         vdev_disk_t *dvd = vd->vdev_tsd;
 290         ldi_ev_cookie_t ecookie;
 291         vdev_disk_ldi_cb_t *lcb;
 292         union {
 293                 struct dk_minfo_ext ude;
 294                 struct dk_minfo ud;
 295         } dks;
 296         struct dk_minfo_ext *dkmext = &dks.ude;
 297         struct dk_minfo *dkm = &dks.ud;
 298         int error;
 299         dev_t dev;
 300         int otyp;
 301         boolean_t validate_devid = B_FALSE;
 302         ddi_devid_t devid;
 303         uint64_t capacity = 0, blksz = 0, pbsize;
 304 
 305         /*
 306          * We must have a pathname, and it must be absolute.
 307          */
 308         if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
 309                 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
 310                 return (SET_ERROR(EINVAL));
 311         }
 312 
 313         /*
 314          * Reopen the device if it's not currently open. Otherwise,
 315          * just update the physical size of the device.
 316          */
 317         if (dvd != NULL) {
 318                 if (dvd->vd_ldi_offline && dvd->vd_lh == NULL) {
 319                         /*
 320                          * If we are opening a device in its offline notify
 321                          * context, the LDI handle was just closed. Clean
 322                          * up the LDI event callbacks and free vd->vdev_tsd.
 323                          */
 324                         vdev_disk_free(vd);
 325                 } else {
 326                         ASSERT(vd->vdev_reopening);
 327                         goto skip_open;
 328                 }
 329         }
 330 
 331         /*
 332          * Create vd->vdev_tsd.
 333          */
 334         vdev_disk_alloc(vd);
 335         dvd = vd->vdev_tsd;
 336 
 337         /*
 338          * When opening a disk device, we want to preserve the user's original
 339          * intent.  We always want to open the device by the path the user gave
 340          * us, even if it is one of multiple paths to the same device.  But we
 341          * also want to be able to survive disks being removed/recabled.
 342          * Therefore the sequence of opening devices is:
 343          *
 344          * 1. Try opening the device by path.  For legacy pools without the
 345          *    'whole_disk' property, attempt to fix the path by appending 's0'.
 346          *
 347          * 2. If the devid of the device matches the stored value, return
 348          *    success.
 349          *
 350          * 3. Otherwise, the device may have moved.  Try opening the device
 351          *    by the devid instead.
 352          */
 353         if (vd->vdev_devid != NULL) {
 354                 if (ddi_devid_str_decode(vd->vdev_devid, &dvd->vd_devid,
 355                     &dvd->vd_minor) != 0) {
 356                         vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
 357                         return (SET_ERROR(EINVAL));
 358                 }
 359         }
 360 
 361         error = EINVAL;         /* presume failure */
 362 
 363         if (vd->vdev_path != NULL) {
 364 
 365                 if (vd->vdev_wholedisk == -1ULL) {
 366                         size_t len = strlen(vd->vdev_path) + 3;
 367                         char *buf = kmem_alloc(len, KM_SLEEP);
 368 
 369                         (void) snprintf(buf, len, "%ss0", vd->vdev_path);
 370 
 371                         error = ldi_open_by_name(buf, spa_mode(spa), kcred,
 372                             &dvd->vd_lh, zfs_li);
 373                         if (error == 0) {
 374                                 spa_strfree(vd->vdev_path);
 375                                 vd->vdev_path = buf;
 376                                 vd->vdev_wholedisk = 1ULL;
 377                         } else {
 378                                 kmem_free(buf, len);
 379                         }
 380                 }
 381 
 382                 /*
 383                  * If we have not yet opened the device, try to open it by the
 384                  * specified path.
 385                  */
 386                 if (error != 0) {
 387                         error = ldi_open_by_name(vd->vdev_path, spa_mode(spa),
 388                             kcred, &dvd->vd_lh, zfs_li);
 389                 }
 390 
 391                 /*
 392                  * Compare the devid to the stored value.
 393                  */
 394                 if (error == 0 && vd->vdev_devid != NULL &&
 395                     ldi_get_devid(dvd->vd_lh, &devid) == 0) {
 396                         if (ddi_devid_compare(devid, dvd->vd_devid) != 0) {
 397                                 error = SET_ERROR(EINVAL);
 398                                 (void) ldi_close(dvd->vd_lh, spa_mode(spa),
 399                                     kcred);
 400                                 dvd->vd_lh = NULL;
 401                         }
 402                         ddi_devid_free(devid);
 403                 }
 404 
 405                 /*
 406                  * If we succeeded in opening the device, but 'vdev_wholedisk'
 407                  * is not yet set, then this must be a slice.
 408                  */
 409                 if (error == 0 && vd->vdev_wholedisk == -1ULL)
 410                         vd->vdev_wholedisk = 0;
 411         }
 412 
 413         /*
 414          * If we were unable to open by path, or the devid check fails, open by
 415          * devid instead.
 416          */
 417         if (error != 0 && vd->vdev_devid != NULL) {
 418                 error = ldi_open_by_devid(dvd->vd_devid, dvd->vd_minor,
 419                     spa_mode(spa), kcred, &dvd->vd_lh, zfs_li);
 420         }
 421 
 422         /*
 423          * If all else fails, then try opening by physical path (if available)
 424          * or the logical path (if we failed due to the devid check).  While not
 425          * as reliable as the devid, this will give us something, and the higher
 426          * level vdev validation will prevent us from opening the wrong device.
 427          */
 428         if (error) {
 429                 if (vd->vdev_devid != NULL)
 430                         validate_devid = B_TRUE;
 431 
 432                 if (vd->vdev_physpath != NULL &&
 433                     (dev = ddi_pathname_to_dev_t(vd->vdev_physpath)) != NODEV)
 434                         error = ldi_open_by_dev(&dev, OTYP_BLK, spa_mode(spa),
 435                             kcred, &dvd->vd_lh, zfs_li);
 436 
 437                 /*
 438                  * Note that we don't support the legacy auto-wholedisk support
 439                  * as above.  This hasn't been used in a very long time and we
 440                  * don't need to propagate its oddities to this edge condition.
 441                  */
 442                 if (error && vd->vdev_path != NULL)
 443                         error = ldi_open_by_name(vd->vdev_path, spa_mode(spa),
 444                             kcred, &dvd->vd_lh, zfs_li);
 445         }
 446 
 447         if (error) {
 448                 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 449                 return (error);
 450         }
 451 
 452         /*
 453          * Now that the device has been successfully opened, update the devid
 454          * if necessary.
 455          */
 456         if (validate_devid && spa_writeable(spa) &&
 457             ldi_get_devid(dvd->vd_lh, &devid) == 0) {
 458                 if (ddi_devid_compare(devid, dvd->vd_devid) != 0) {
 459                         char *vd_devid;
 460 
 461                         vd_devid = ddi_devid_str_encode(devid, dvd->vd_minor);
 462                         zfs_dbgmsg("vdev %s: update devid from %s, "
 463                             "to %s", vd->vdev_path, vd->vdev_devid, vd_devid);
 464                         spa_strfree(vd->vdev_devid);
 465                         vd->vdev_devid = spa_strdup(vd_devid);
 466                         ddi_devid_str_free(vd_devid);
 467                 }
 468                 ddi_devid_free(devid);
 469         }
 470 
 471         /*
 472          * Once a device is opened, verify that the physical device path (if
 473          * available) is up to date.
 474          */
 475         if (ldi_get_dev(dvd->vd_lh, &dev) == 0 &&
 476             ldi_get_otyp(dvd->vd_lh, &otyp) == 0) {
 477                 char *physpath, *minorname;
 478 
 479                 physpath = kmem_alloc(MAXPATHLEN, KM_SLEEP);
 480                 minorname = NULL;
 481                 if (ddi_dev_pathname(dev, otyp, physpath) == 0 &&
 482                     ldi_get_minor_name(dvd->vd_lh, &minorname) == 0 &&
 483                     (vd->vdev_physpath == NULL ||
 484                     strcmp(vd->vdev_physpath, physpath) != 0)) {
 485                         if (vd->vdev_physpath)
 486                                 spa_strfree(vd->vdev_physpath);
 487                         (void) strlcat(physpath, ":", MAXPATHLEN);
 488                         (void) strlcat(physpath, minorname, MAXPATHLEN);
 489                         vd->vdev_physpath = spa_strdup(physpath);
 490                 }
 491                 if (minorname)
 492                         kmem_free(minorname, strlen(minorname) + 1);
 493                 kmem_free(physpath, MAXPATHLEN);
 494         }
 495 
 496         /*
 497          * Register callbacks for the LDI offline event.
 498          */
 499         if (ldi_ev_get_cookie(dvd->vd_lh, LDI_EV_OFFLINE, &ecookie) ==
 500             LDI_EV_SUCCESS) {
 501                 lcb = kmem_zalloc(sizeof (vdev_disk_ldi_cb_t), KM_SLEEP);
 502                 list_insert_tail(&dvd->vd_ldi_cbs, lcb);
 503                 (void) ldi_ev_register_callbacks(dvd->vd_lh, ecookie,
 504                     &vdev_disk_off_callb, (void *) vd, &lcb->lcb_id);
 505         }
 506 
 507         /*
 508          * Register callbacks for the LDI degrade event.
 509          */
 510         if (ldi_ev_get_cookie(dvd->vd_lh, LDI_EV_DEGRADE, &ecookie) ==
 511             LDI_EV_SUCCESS) {
 512                 lcb = kmem_zalloc(sizeof (vdev_disk_ldi_cb_t), KM_SLEEP);
 513                 list_insert_tail(&dvd->vd_ldi_cbs, lcb);
 514                 (void) ldi_ev_register_callbacks(dvd->vd_lh, ecookie,
 515                     &vdev_disk_dgrd_callb, (void *) vd, &lcb->lcb_id);
 516         }
 517 skip_open:
 518         /*
 519          * Determine the actual size of the device.
 520          */
 521         if (ldi_get_size(dvd->vd_lh, psize) != 0) {
 522                 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 523                 return (SET_ERROR(EINVAL));
 524         }
 525 
 526         *max_psize = *psize;
 527 
 528         /*
 529          * Determine the device's minimum transfer size.
 530          * If the ioctl isn't supported, assume DEV_BSIZE.
 531          */
 532         if ((error = ldi_ioctl(dvd->vd_lh, DKIOCGMEDIAINFOEXT,
 533             (intptr_t)dkmext, FKIOCTL, kcred, NULL)) == 0) {
 534                 capacity = dkmext->dki_capacity - 1;
 535                 blksz = dkmext->dki_lbsize;
 536                 pbsize = dkmext->dki_pbsize;
 537         } else if ((error = ldi_ioctl(dvd->vd_lh, DKIOCGMEDIAINFO,
 538             (intptr_t)dkm, FKIOCTL, kcred, NULL)) == 0) {
 539                 VDEV_DEBUG(
 540                     "vdev_disk_open(\"%s\"): fallback to DKIOCGMEDIAINFO\n",
 541                     vd->vdev_path);
 542                 capacity = dkm->dki_capacity - 1;
 543                 blksz = dkm->dki_lbsize;
 544                 pbsize = blksz;
 545         } else {
 546                 VDEV_DEBUG("vdev_disk_open(\"%s\"): "
 547                     "both DKIOCGMEDIAINFO{,EXT} calls failed, %d\n",
 548                     vd->vdev_path, error);
 549                 pbsize = DEV_BSIZE;
 550         }
 551 
 552         *ashift = highbit(MAX(pbsize, SPA_MINBLOCKSIZE)) - 1;
 553 
 554         if (vd->vdev_wholedisk == 1) {
 555                 int wce = 1;
 556 
 557                 if (error == 0) {
 558                         /*
 559                          * If we have the capability to expand, we'd have
 560                          * found out via success from DKIOCGMEDIAINFO{,EXT}.
 561                          * Adjust max_psize upward accordingly since we know
 562                          * we own the whole disk now.
 563                          */
 564                         *max_psize += vdev_disk_get_space(vd, capacity, blksz);
 565                         zfs_dbgmsg("capacity change: vdev %s, psize %llu, "
 566                             "max_psize %llu", vd->vdev_path, *psize,
 567                             *max_psize);
 568                 }
 569 
 570                 /*
 571                  * Since we own the whole disk, try to enable disk write
 572                  * caching.  We ignore errors because it's OK if we can't do it.
 573                  */
 574                 (void) ldi_ioctl(dvd->vd_lh, DKIOCSETWCE, (intptr_t)&wce,
 575                     FKIOCTL, kcred, NULL);
 576         }
 577 
 578         /*
 579          * Clear the nowritecache bit, so that on a vdev_reopen() we will
 580          * try again.
 581          */
 582         vd->vdev_nowritecache = B_FALSE;
 583 
 584         return (0);
 585 }
 586 
 587 static void
 588 vdev_disk_close(vdev_t *vd)
 589 {
 590         vdev_disk_t *dvd = vd->vdev_tsd;
 591 
 592         if (vd->vdev_reopening || dvd == NULL)
 593                 return;
 594 
 595         if (dvd->vd_minor != NULL) {
 596                 ddi_devid_str_free(dvd->vd_minor);
 597                 dvd->vd_minor = NULL;
 598         }
 599 
 600         if (dvd->vd_devid != NULL) {
 601                 ddi_devid_free(dvd->vd_devid);
 602                 dvd->vd_devid = NULL;
 603         }
 604 
 605         if (dvd->vd_lh != NULL) {
 606                 (void) ldi_close(dvd->vd_lh, spa_mode(vd->vdev_spa), kcred);
 607                 dvd->vd_lh = NULL;
 608         }
 609 
 610         vd->vdev_delayed_close = B_FALSE;
 611         /*
 612          * If we closed the LDI handle due to an offline notify from LDI,
 613          * don't free vd->vdev_tsd or unregister the callbacks here;
 614          * the offline finalize callback or a reopen will take care of it.
 615          */
 616         if (dvd->vd_ldi_offline)
 617                 return;
 618 
 619         vdev_disk_free(vd);
 620 }
 621 
 622 int
 623 vdev_disk_physio(vdev_t *vd, caddr_t data,
 624     size_t size, uint64_t offset, int flags, boolean_t isdump)
 625 {
 626         vdev_disk_t *dvd = vd->vdev_tsd;
 627 
 628         /*
 629          * If the vdev is closed, it's likely in the REMOVED or FAULTED state.
 630          * Nothing to be done here but return failure.
 631          */
 632         if (dvd == NULL || (dvd->vd_ldi_offline && dvd->vd_lh == NULL))
 633                 return (EIO);
 634 
 635         ASSERT(vd->vdev_ops == &vdev_disk_ops);
 636 
 637         /*
 638          * If in the context of an active crash dump, use the ldi_dump(9F)
 639          * call instead of ldi_strategy(9F) as usual.
 640          */
 641         if (isdump) {
 642                 ASSERT3P(dvd, !=, NULL);
 643                 return (ldi_dump(dvd->vd_lh, data, lbtodb(offset),
 644                     lbtodb(size)));
 645         }
 646 
 647         return (vdev_disk_ldi_physio(dvd->vd_lh, data, size, offset, flags));
 648 }
 649 
 650 int
 651 vdev_disk_ldi_physio(ldi_handle_t vd_lh, caddr_t data,
 652     size_t size, uint64_t offset, int flags)
 653 {
 654         buf_t *bp;
 655         int error = 0;
 656 
 657         if (vd_lh == NULL)
 658                 return (SET_ERROR(EINVAL));
 659 
 660         ASSERT(flags & B_READ || flags & B_WRITE);
 661 
 662         bp = getrbuf(KM_SLEEP);
 663         bp->b_flags = flags | B_BUSY | B_NOCACHE | B_FAILFAST;
 664         bp->b_bcount = size;
 665         bp->b_un.b_addr = (void *)data;
 666         bp->b_lblkno = lbtodb(offset);
 667         bp->b_bufsize = size;
 668 
 669         error = ldi_strategy(vd_lh, bp);
 670         ASSERT(error == 0);
 671         if ((error = biowait(bp)) == 0 && bp->b_resid != 0)
 672                 error = SET_ERROR(EIO);
 673         freerbuf(bp);
 674 
 675         return (error);
 676 }
 677 
 678 static void
 679 vdev_disk_io_intr(buf_t *bp)
 680 {
 681         vdev_buf_t *vb = (vdev_buf_t *)bp;
 682         zio_t *zio = vb->vb_io;
 683 
 684         /*
 685          * The rest of the zio stack only deals with EIO, ECKSUM, and ENXIO.
 686          * Rather than teach the rest of the stack about other error
 687          * possibilities (EFAULT, etc), we normalize the error value here.
 688          */
 689         zio->io_error = (geterror(bp) != 0 ? EIO : 0);
 690 
 691         if (zio->io_error == 0 && bp->b_resid != 0)
 692                 zio->io_error = SET_ERROR(EIO);
 693 
 694         kmem_free(vb, sizeof (vdev_buf_t));
 695 
 696         zio_interrupt(zio);
 697 }
 698 
 699 static void
 700 vdev_disk_ioctl_free(zio_t *zio)
 701 {
 702         kmem_free(zio->io_vsd, sizeof (struct dk_callback));
 703 }
 704 
 705 static const zio_vsd_ops_t vdev_disk_vsd_ops = {
 706         vdev_disk_ioctl_free,
 707         zio_vsd_default_cksum_report
 708 };
 709 
 710 static void
 711 vdev_disk_ioctl_done(void *zio_arg, int error)
 712 {
 713         zio_t *zio = zio_arg;
 714 
 715         zio->io_error = error;
 716 
 717         zio_interrupt(zio);
 718 }
 719 
 720 static int
 721 vdev_disk_io_start(zio_t *zio)
 722 {
 723         vdev_t *vd = zio->io_vd;
 724         vdev_disk_t *dvd = vd->vdev_tsd;
 725         vdev_buf_t *vb;
 726         struct dk_callback *dkc;
 727         buf_t *bp;
 728         int error;
 729 
 730         /*
 731          * If the vdev is closed, it's likely in the REMOVED or FAULTED state.
 732          * Nothing to be done here but return failure.
 733          */
 734         if (dvd == NULL || (dvd->vd_ldi_offline && dvd->vd_lh == NULL)) {
 735                 zio->io_error = ENXIO;
 736                 return (ZIO_PIPELINE_CONTINUE);
 737         }
 738 
 739         if (zio->io_type == ZIO_TYPE_IOCTL) {
 740                 /* XXPOLICY */
 741                 if (!vdev_readable(vd)) {
 742                         zio->io_error = SET_ERROR(ENXIO);
 743                         return (ZIO_PIPELINE_CONTINUE);
 744                 }
 745 
 746                 switch (zio->io_cmd) {
 747 
 748                 case DKIOCFLUSHWRITECACHE:
 749 
 750                         if (zfs_nocacheflush)
 751                                 break;
 752 
 753                         if (vd->vdev_nowritecache) {
 754                                 zio->io_error = SET_ERROR(ENOTSUP);
 755                                 break;
 756                         }
 757 
 758                         zio->io_vsd = dkc = kmem_alloc(sizeof (*dkc), KM_SLEEP);
 759                         zio->io_vsd_ops = &vdev_disk_vsd_ops;
 760 
 761                         dkc->dkc_callback = vdev_disk_ioctl_done;
 762                         dkc->dkc_flag = FLUSH_VOLATILE;
 763                         dkc->dkc_cookie = zio;
 764 
 765                         error = ldi_ioctl(dvd->vd_lh, zio->io_cmd,
 766                             (uintptr_t)dkc, FKIOCTL, kcred, NULL);
 767 
 768                         if (error == 0) {
 769                                 /*
 770                                  * The ioctl will be done asychronously,
 771                                  * and will call vdev_disk_ioctl_done()
 772                                  * upon completion.
 773                                  */
 774                                 return (ZIO_PIPELINE_STOP);
 775                         }
 776 
 777                         if (error == ENOTSUP || error == ENOTTY) {
 778                                 /*
 779                                  * If we get ENOTSUP or ENOTTY, we know that
 780                                  * no future attempts will ever succeed.
 781                                  * In this case we set a persistent bit so
 782                                  * that we don't bother with the ioctl in the
 783                                  * future.
 784                                  */
 785                                 vd->vdev_nowritecache = B_TRUE;
 786                         }
 787                         zio->io_error = error;
 788 
 789                         break;
 790 
 791                 default:
 792                         zio->io_error = SET_ERROR(ENOTSUP);
 793                 }
 794 
 795                 return (ZIO_PIPELINE_CONTINUE);
 796         }
 797 
 798         vb = kmem_alloc(sizeof (vdev_buf_t), KM_SLEEP);
 799 
 800         vb->vb_io = zio;
 801         bp = &vb->vb_buf;
 802 
 803         bioinit(bp);
 804         bp->b_flags = B_BUSY | B_NOCACHE |
 805             (zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE);
 806         if (!(zio->io_flags & (ZIO_FLAG_IO_RETRY | ZIO_FLAG_TRYHARD)))
 807                 bp->b_flags |= B_FAILFAST;
 808         bp->b_bcount = zio->io_size;
 809         bp->b_un.b_addr = zio->io_data;
 810         bp->b_lblkno = lbtodb(zio->io_offset);
 811         bp->b_bufsize = zio->io_size;
 812         bp->b_iodone = (int (*)())vdev_disk_io_intr;
 813 
 814         /* ldi_strategy() will return non-zero only on programming errors */
 815         VERIFY(ldi_strategy(dvd->vd_lh, bp) == 0);
 816 
 817         return (ZIO_PIPELINE_STOP);
 818 }
 819 
 820 static void
 821 vdev_disk_io_done(zio_t *zio)
 822 {
 823         vdev_t *vd = zio->io_vd;
 824 
 825         /*
 826          * If the device returned EIO, then attempt a DKIOCSTATE ioctl to see if
 827          * the device has been removed.  If this is the case, then we trigger an
 828          * asynchronous removal of the device. Otherwise, probe the device and
 829          * make sure it's still accessible.
 830          */
 831         if (zio->io_error == EIO && !vd->vdev_remove_wanted) {
 832                 vdev_disk_t *dvd = vd->vdev_tsd;
 833                 int state = DKIO_NONE;
 834 
 835                 if (ldi_ioctl(dvd->vd_lh, DKIOCSTATE, (intptr_t)&state,
 836                     FKIOCTL, kcred, NULL) == 0 && state != DKIO_INSERTED) {
 837                         /*
 838                          * We post the resource as soon as possible, instead of
 839                          * when the async removal actually happens, because the
 840                          * DE is using this information to discard previous I/O
 841                          * errors.
 842                          */
 843                         zfs_post_remove(zio->io_spa, vd);
 844                         vd->vdev_remove_wanted = B_TRUE;
 845                         spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE);
 846                 } else if (!vd->vdev_delayed_close) {
 847                         vd->vdev_delayed_close = B_TRUE;
 848                 }
 849         }
 850 }
 851 
 852 vdev_ops_t vdev_disk_ops = {
 853         vdev_disk_open,
 854         vdev_disk_close,
 855         vdev_default_asize,
 856         vdev_disk_io_start,
 857         vdev_disk_io_done,
 858         NULL,
 859         vdev_disk_hold,
 860         vdev_disk_rele,
 861         VDEV_TYPE_DISK,         /* name of this vdev type */
 862         B_TRUE                  /* leaf vdev */
 863 };
 864 
 865 /*
 866  * Given the root disk device devid or pathname, read the label from
 867  * the device, and construct a configuration nvlist.
 868  */
 869 int
 870 vdev_disk_read_rootlabel(char *devpath, char *devid, nvlist_t **config)
 871 {
 872         ldi_handle_t vd_lh;
 873         vdev_label_t *label;
 874         uint64_t s, size;
 875         int l;
 876         ddi_devid_t tmpdevid;
 877         int error = -1;
 878         char *minor_name;
 879 
 880         /*
 881          * Read the device label and build the nvlist.
 882          */
 883         if (devid != NULL && ddi_devid_str_decode(devid, &tmpdevid,
 884             &minor_name) == 0) {
 885                 error = ldi_open_by_devid(tmpdevid, minor_name,
 886                     FREAD, kcred, &vd_lh, zfs_li);
 887                 ddi_devid_free(tmpdevid);
 888                 ddi_devid_str_free(minor_name);
 889         }
 890 
 891         if (error && (error = ldi_open_by_name(devpath, FREAD, kcred, &vd_lh,
 892             zfs_li)))
 893                 return (error);
 894 
 895         if (ldi_get_size(vd_lh, &s)) {
 896                 (void) ldi_close(vd_lh, FREAD, kcred);
 897                 return (SET_ERROR(EIO));
 898         }
 899 
 900         size = P2ALIGN_TYPED(s, sizeof (vdev_label_t), uint64_t);
 901         label = kmem_alloc(sizeof (vdev_label_t), KM_SLEEP);
 902 
 903         *config = NULL;
 904         for (l = 0; l < VDEV_LABELS; l++) {
 905                 uint64_t offset, state, txg = 0;
 906 
 907                 /* read vdev label */
 908                 offset = vdev_label_offset(size, l, 0);
 909                 if (vdev_disk_ldi_physio(vd_lh, (caddr_t)label,
 910                     VDEV_SKIP_SIZE + VDEV_PHYS_SIZE, offset, B_READ) != 0)
 911                         continue;
 912 
 913                 if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
 914                     sizeof (label->vl_vdev_phys.vp_nvlist), config, 0) != 0) {
 915                         *config = NULL;
 916                         continue;
 917                 }
 918 
 919                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
 920                     &state) != 0 || state >= POOL_STATE_DESTROYED) {
 921                         nvlist_free(*config);
 922                         *config = NULL;
 923                         continue;
 924                 }
 925 
 926                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
 927                     &txg) != 0 || txg == 0) {
 928                         nvlist_free(*config);
 929                         *config = NULL;
 930                         continue;
 931                 }
 932 
 933                 break;
 934         }
 935 
 936         kmem_free(label, sizeof (vdev_label_t));
 937         (void) ldi_close(vd_lh, FREAD, kcred);
 938         if (*config == NULL)
 939                 error = SET_ERROR(EIDRM);
 940 
 941         return (error);
 942 }