sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  24  * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  25  * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  26  * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  27  * Copyright 2014 HybridCluster. All rights reserved.
  28  */
  29
  30 #include <sys/dmu.h>
  31 #include <sys/dmu_impl.h>
  32 #include <sys/dmu_tx.h>
  33 #include <sys/dbuf.h>
  34 #include <sys/dnode.h>
  35 #include <sys/zfs_context.h>
  36 #include <sys/dmu_objset.h>
  37 #include <sys/dmu_traverse.h>
  38 #include <sys/dsl_dataset.h>
  39 #include <sys/dsl_dir.h>
  40 #include <sys/dsl_prop.h>
  41 #include <sys/dsl_pool.h>
  42 #include <sys/dsl_synctask.h>
  43 #include <sys/zfs_ioctl.h>
  44 #include <sys/zap.h>
  45 #include <sys/zio_checksum.h>
  46 #include <sys/zfs_znode.h>
  47 #include <zfs_fletcher.h>
  48 #include <sys/avl.h>
  49 #include <sys/ddt.h>
  50 #include <sys/zfs_onexit.h>
  51 #include <sys/dmu_send.h>
  52 #include <sys/dsl_destroy.h>
  53 #include <sys/blkptr.h>
  54 #include <sys/dsl_bookmark.h>
  55 #include <sys/zfeature.h>
  56
  57 #ifdef __FreeBSD__
  58 #undef dump_write
  59 #define dump_write dmu_dump_write
  60 #endif
  61
  62 /* Set this tunable to TRUE to replace corrupt data with 0x2f5baddb10c */
  63 int zfs_send_corrupt_data = B_FALSE;
  64
  65 static char *dmu_recv_tag = "dmu_recv_tag";
  66 static const char *recv_clone_name = "%recv";
  67
  68 static int
  69 dump_bytes(dmu_sendarg_t *dsp, void *buf, int len)
  70 {
  71         dsl_dataset_t *ds = dsp->dsa_os->os_dsl_dataset;
  72         struct uio auio;
  73         struct iovec aiov;
  74         ASSERT0(len % 8);
  75
  76         aiov.iov_base = buf;
  77         aiov.iov_len = len;
  78         auio.uio_iov = &aiov;
  79         auio.uio_iovcnt = 1;
  80         auio.uio_resid = len;
  81         auio.uio_segflg = UIO_SYSSPACE;
  82         auio.uio_rw = UIO_WRITE;
  83         auio.uio_offset = (off_t)-1;
  84         auio.uio_td = dsp->dsa_td;
  85 #ifdef _KERNEL
  86         if (dsp->dsa_fp->f_type == DTYPE_VNODE)
  87                 bwillwrite();
  88         dsp->dsa_err = fo_write(dsp->dsa_fp, &auio, dsp->dsa_td->td_ucred, 0,
  89             dsp->dsa_td);
  90 #else
  91         fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__);
  92         dsp->dsa_err = EOPNOTSUPP;
  93 #endif
  94         mutex_enter(&ds->ds_sendstream_lock);
  95         *dsp->dsa_off += len;
  96         mutex_exit(&ds->ds_sendstream_lock);
  97
  98         return (dsp->dsa_err);
  99 }
 100
 101 /*
 102  * For all record types except BEGIN, fill in the checksum (overlaid in
 103  * drr_u.drr_checksum.drr_checksum).  The checksum verifies everything
 104  * up to the start of the checksum itself.
 105  */
 106 static int
 107 dump_record(dmu_sendarg_t *dsp, void *payload, int payload_len)
 108 {
 109         ASSERT3U(offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
 110             ==, sizeof (dmu_replay_record_t) - sizeof (zio_cksum_t));
 111         fletcher_4_incremental_native(dsp->dsa_drr,
 112             offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
 113             &dsp->dsa_zc);
 114         if (dsp->dsa_drr->drr_type != DRR_BEGIN) {
 115                 ASSERT(ZIO_CHECKSUM_IS_ZERO(&dsp->dsa_drr->drr_u.
 116                     drr_checksum.drr_checksum));
 117                 dsp->dsa_drr->drr_u.drr_checksum.drr_checksum = dsp->dsa_zc;
 118         }
 119         fletcher_4_incremental_native(&dsp->dsa_drr->
 120             drr_u.drr_checksum.drr_checksum,
 121             sizeof (zio_cksum_t), &dsp->dsa_zc);
 122         if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)) != 0)
 123                 return (SET_ERROR(EINTR));
 124         if (payload_len != 0) {
 125                 fletcher_4_incremental_native(payload, payload_len,
 126                     &dsp->dsa_zc);
 127                 if (dump_bytes(dsp, payload, payload_len) != 0)
 128                         return (SET_ERROR(EINTR));
 129         }
 130         return (0);
 131 }
 132
 133 static int
 134 dump_free(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
 135     uint64_t length)
 136 {
 137         struct drr_free *drrf = &(dsp->dsa_drr->drr_u.drr_free);
 138
 139         /*
 140          * When we receive a free record, dbuf_free_range() assumes
 141          * that the receiving system doesn't have any dbufs in the range
 142          * being freed.  This is always true because there is a one-record
 143          * constraint: we only send one WRITE record for any given
 144          * object+offset.  We know that the one-record constraint is
 145          * true because we always send data in increasing order by
 146          * object,offset.
 147          *
 148          * If the increasing-order constraint ever changes, we should find
 149          * another way to assert that the one-record constraint is still
 150          * satisfied.
 151          */
 152         ASSERT(object > dsp->dsa_last_data_object ||
 153             (object == dsp->dsa_last_data_object &&
 154             offset > dsp->dsa_last_data_offset));
 155
 156         /*
 157          * If we are doing a non-incremental send, then there can't
 158          * be any data in the dataset we're receiving into.  Therefore
 159          * a free record would simply be a no-op.  Save space by not
 160          * sending it to begin with.
 161          */
 162         if (!dsp->dsa_incremental)
 163                 return (0);
 164
 165         if (length != -1ULL && offset + length < offset)
 166                 length = -1ULL;
 167
 168         /*
 169          * If there is a pending op, but it's not PENDING_FREE, push it out,
 170          * since free block aggregation can only be done for blocks of the
 171          * same type (i.e., DRR_FREE records can only be aggregated with
 172          * other DRR_FREE records.  DRR_FREEOBJECTS records can only be
 173          * aggregated with other DRR_FREEOBJECTS records.
 174          */
 175         if (dsp->dsa_pending_op != PENDING_NONE &&
 176             dsp->dsa_pending_op != PENDING_FREE) {
 177                 if (dump_record(dsp, NULL, 0) != 0)
 178                         return (SET_ERROR(EINTR));
 179                 dsp->dsa_pending_op = PENDING_NONE;
 180         }
 181
 182         if (dsp->dsa_pending_op == PENDING_FREE) {
 183                 /*
 184                  * There should never be a PENDING_FREE if length is -1
 185                  * (because dump_dnode is the only place where this
 186                  * function is called with a -1, and only after flushing
 187                  * any pending record).
 188                  */
 189                 ASSERT(length != -1ULL);
 190                 /*
 191                  * Check to see whether this free block can be aggregated
 192                  * with pending one.
 193                  */
 194                 if (drrf->drr_object == object && drrf->drr_offset +
 195                     drrf->drr_length == offset) {
 196                         drrf->drr_length += length;
 197                         return (0);
 198                 } else {
 199                         /* not a continuation.  Push out pending record */
 200                         if (dump_record(dsp, NULL, 0) != 0)
 201                                 return (SET_ERROR(EINTR));
 202                         dsp->dsa_pending_op = PENDING_NONE;
 203                 }
 204         }
 205         /* create a FREE record and make it pending */
 206         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 207         dsp->dsa_drr->drr_type = DRR_FREE;
 208         drrf->drr_object = object;
 209         drrf->drr_offset = offset;
 210         drrf->drr_length = length;
 211         drrf->drr_toguid = dsp->dsa_toguid;
 212         if (length == -1ULL) {
 213                 if (dump_record(dsp, NULL, 0) != 0)
 214                         return (SET_ERROR(EINTR));
 215         } else {
 216                 dsp->dsa_pending_op = PENDING_FREE;
 217         }
 218
 219         return (0);
 220 }
 221
 222 static int
 223 dump_write(dmu_sendarg_t *dsp, dmu_object_type_t type,
 224     uint64_t object, uint64_t offset, int blksz, const blkptr_t *bp, void *data)
 225 {
 226         struct drr_write *drrw = &(dsp->dsa_drr->drr_u.drr_write);
 227
 228         /*
 229          * We send data in increasing object, offset order.
 230          * See comment in dump_free() for details.
 231          */
 232         ASSERT(object > dsp->dsa_last_data_object ||
 233             (object == dsp->dsa_last_data_object &&
 234             offset > dsp->dsa_last_data_offset));
 235         dsp->dsa_last_data_object = object;
 236         dsp->dsa_last_data_offset = offset + blksz - 1;
 237
 238         /*
 239          * If there is any kind of pending aggregation (currently either
 240          * a grouping of free objects or free blocks), push it out to
 241          * the stream, since aggregation can't be done across operations
 242          * of different types.
 243          */
 244         if (dsp->dsa_pending_op != PENDING_NONE) {
 245                 if (dump_record(dsp, NULL, 0) != 0)
 246                         return (SET_ERROR(EINTR));
 247                 dsp->dsa_pending_op = PENDING_NONE;
 248         }
 249         /* write a WRITE record */
 250         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 251         dsp->dsa_drr->drr_type = DRR_WRITE;
 252         drrw->drr_object = object;
 253         drrw->drr_type = type;
 254         drrw->drr_offset = offset;
 255         drrw->drr_length = blksz;
 256         drrw->drr_toguid = dsp->dsa_toguid;
 257         if (bp == NULL || BP_IS_EMBEDDED(bp)) {
 258                 /*
 259                  * There's no pre-computed checksum for partial-block
 260                  * writes or embedded BP's, so (like
 261                  * fletcher4-checkummed blocks) userland will have to
 262                  * compute a dedup-capable checksum itself.
 263                  */
 264                 drrw->drr_checksumtype = ZIO_CHECKSUM_OFF;
 265         } else {
 266                 drrw->drr_checksumtype = BP_GET_CHECKSUM(bp);
 267                 if (zio_checksum_table[drrw->drr_checksumtype].ci_dedup)
 268                         drrw->drr_checksumflags |= DRR_CHECKSUM_DEDUP;
 269                 DDK_SET_LSIZE(&drrw->drr_key, BP_GET_LSIZE(bp));
 270                 DDK_SET_PSIZE(&drrw->drr_key, BP_GET_PSIZE(bp));
 271                 DDK_SET_COMPRESS(&drrw->drr_key, BP_GET_COMPRESS(bp));
 272                 drrw->drr_key.ddk_cksum = bp->blk_cksum;
 273         }
 274
 275         if (dump_record(dsp, data, blksz) != 0)
 276                 return (SET_ERROR(EINTR));
 277         return (0);
 278 }
 279
 280 static int
 281 dump_write_embedded(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
 282     int blksz, const blkptr_t *bp)
 283 {
 284         char buf[BPE_PAYLOAD_SIZE];
 285         struct drr_write_embedded *drrw =
 286             &(dsp->dsa_drr->drr_u.drr_write_embedded);
 287
 288         if (dsp->dsa_pending_op != PENDING_NONE) {
 289                 if (dump_record(dsp, NULL, 0) != 0)
 290                         return (EINTR);
 291                 dsp->dsa_pending_op = PENDING_NONE;
 292         }
 293
 294         ASSERT(BP_IS_EMBEDDED(bp));
 295
 296         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 297         dsp->dsa_drr->drr_type = DRR_WRITE_EMBEDDED;
 298         drrw->drr_object = object;
 299         drrw->drr_offset = offset;
 300         drrw->drr_length = blksz;
 301         drrw->drr_toguid = dsp->dsa_toguid;
 302         drrw->drr_compression = BP_GET_COMPRESS(bp);
 303         drrw->drr_etype = BPE_GET_ETYPE(bp);
 304         drrw->drr_lsize = BPE_GET_LSIZE(bp);
 305         drrw->drr_psize = BPE_GET_PSIZE(bp);
 306
 307         decode_embedded_bp_compressed(bp, buf);
 308
 309         if (dump_record(dsp, buf, P2ROUNDUP(drrw->drr_psize, 8)) != 0)
 310                 return (EINTR);
 311         return (0);
 312 }
 313
 314 static int
 315 dump_spill(dmu_sendarg_t *dsp, uint64_t object, int blksz, void *data)
 316 {
 317         struct drr_spill *drrs = &(dsp->dsa_drr->drr_u.drr_spill);
 318
 319         if (dsp->dsa_pending_op != PENDING_NONE) {
 320                 if (dump_record(dsp, NULL, 0) != 0)
 321                         return (SET_ERROR(EINTR));
 322                 dsp->dsa_pending_op = PENDING_NONE;
 323         }
 324
 325         /* write a SPILL record */
 326         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 327         dsp->dsa_drr->drr_type = DRR_SPILL;
 328         drrs->drr_object = object;
 329         drrs->drr_length = blksz;
 330         drrs->drr_toguid = dsp->dsa_toguid;
 331
 332         if (dump_record(dsp, data, blksz) != 0)
 333                 return (SET_ERROR(EINTR));
 334         return (0);
 335 }
 336
 337 static int
 338 dump_freeobjects(dmu_sendarg_t *dsp, uint64_t firstobj, uint64_t numobjs)
 339 {
 340         struct drr_freeobjects *drrfo = &(dsp->dsa_drr->drr_u.drr_freeobjects);
 341
 342         /* See comment in dump_free(). */
 343         if (!dsp->dsa_incremental)
 344                 return (0);
 345
 346         /*
 347          * If there is a pending op, but it's not PENDING_FREEOBJECTS,
 348          * push it out, since free block aggregation can only be done for
 349          * blocks of the same type (i.e., DRR_FREE records can only be
 350          * aggregated with other DRR_FREE records.  DRR_FREEOBJECTS records
 351          * can only be aggregated with other DRR_FREEOBJECTS records.
 352          */
 353         if (dsp->dsa_pending_op != PENDING_NONE &&
 354             dsp->dsa_pending_op != PENDING_FREEOBJECTS) {
 355                 if (dump_record(dsp, NULL, 0) != 0)
 356                         return (SET_ERROR(EINTR));
 357                 dsp->dsa_pending_op = PENDING_NONE;
 358         }
 359         if (dsp->dsa_pending_op == PENDING_FREEOBJECTS) {
 360                 /*
 361                  * See whether this free object array can be aggregated
 362                  * with pending one
 363                  */
 364                 if (drrfo->drr_firstobj + drrfo->drr_numobjs == firstobj) {
 365                         drrfo->drr_numobjs += numobjs;
 366                         return (0);
 367                 } else {
 368                         /* can't be aggregated.  Push out pending record */
 369                         if (dump_record(dsp, NULL, 0) != 0)
 370                                 return (SET_ERROR(EINTR));
 371                         dsp->dsa_pending_op = PENDING_NONE;
 372                 }
 373         }
 374
 375         /* write a FREEOBJECTS record */
 376         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 377         dsp->dsa_drr->drr_type = DRR_FREEOBJECTS;
 378         drrfo->drr_firstobj = firstobj;
 379         drrfo->drr_numobjs = numobjs;
 380         drrfo->drr_toguid = dsp->dsa_toguid;
 381
 382         dsp->dsa_pending_op = PENDING_FREEOBJECTS;
 383
 384         return (0);
 385 }
 386
 387 static int
 388 dump_dnode(dmu_sendarg_t *dsp, uint64_t object, dnode_phys_t *dnp)
 389 {
 390         struct drr_object *drro = &(dsp->dsa_drr->drr_u.drr_object);
 391
 392         if (dnp == NULL || dnp->dn_type == DMU_OT_NONE)
 393                 return (dump_freeobjects(dsp, object, 1));
 394
 395         if (dsp->dsa_pending_op != PENDING_NONE) {
 396                 if (dump_record(dsp, NULL, 0) != 0)
 397                         return (SET_ERROR(EINTR));
 398                 dsp->dsa_pending_op = PENDING_NONE;
 399         }
 400
 401         /* write an OBJECT record */
 402         bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
 403         dsp->dsa_drr->drr_type = DRR_OBJECT;
 404         drro->drr_object = object;
 405         drro->drr_type = dnp->dn_type;
 406         drro->drr_bonustype = dnp->dn_bonustype;
 407         drro->drr_blksz = dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 408         drro->drr_bonuslen = dnp->dn_bonuslen;
 409         drro->drr_checksumtype = dnp->dn_checksum;
 410         drro->drr_compress = dnp->dn_compress;
 411         drro->drr_toguid = dsp->dsa_toguid;
 412
 413         if (!(dsp->dsa_featureflags & DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
 414             drro->drr_blksz > SPA_OLD_MAXBLOCKSIZE)
 415                 drro->drr_blksz = SPA_OLD_MAXBLOCKSIZE;
 416
 417         if (dump_record(dsp, DN_BONUS(dnp),
 418             P2ROUNDUP(dnp->dn_bonuslen, 8)) != 0) {
 419                 return (SET_ERROR(EINTR));
 420         }
 421
 422         /* Free anything past the end of the file. */
 423         if (dump_free(dsp, object, (dnp->dn_maxblkid + 1) *
 424             (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT), -1ULL) != 0)
 425                 return (SET_ERROR(EINTR));
 426         if (dsp->dsa_err != 0)
 427                 return (SET_ERROR(EINTR));
 428         return (0);
 429 }
 430
 431 static boolean_t
 432 backup_do_embed(dmu_sendarg_t *dsp, const blkptr_t *bp)
 433 {
 434         if (!BP_IS_EMBEDDED(bp))
 435                 return (B_FALSE);
 436
 437         /*
 438          * Compression function must be legacy, or explicitly enabled.
 439          */
 440         if ((BP_GET_COMPRESS(bp) >= ZIO_COMPRESS_LEGACY_FUNCTIONS &&
 441             !(dsp->dsa_featureflags & DMU_BACKUP_FEATURE_EMBED_DATA_LZ4)))
 442                 return (B_FALSE);
 443
 444         /*
 445          * Embed type must be explicitly enabled.
 446          */
 447         switch (BPE_GET_ETYPE(bp)) {
 448         case BP_EMBEDDED_TYPE_DATA:
 449                 if (dsp->dsa_featureflags & DMU_BACKUP_FEATURE_EMBED_DATA)
 450                         return (B_TRUE);
 451                 break;
 452         default:
 453                 return (B_FALSE);
 454         }
 455         return (B_FALSE);
 456 }
 457
 458 #define BP_SPAN(dnp, level) \
 459         (((uint64_t)dnp->dn_datablkszsec) << (SPA_MINBLOCKSHIFT + \
 460         (level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT)))
 461
 462 /* ARGSUSED */
 463 static int
 464 backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
 465     const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
 466 {
 467         dmu_sendarg_t *dsp = arg;
 468         dmu_object_type_t type = bp ? BP_GET_TYPE(bp) : DMU_OT_NONE;
 469         int err = 0;
 470
 471         if (issig(JUSTLOOKING) && issig(FORREAL))
 472                 return (SET_ERROR(EINTR));
 473
 474         if (zb->zb_object != DMU_META_DNODE_OBJECT &&
 475             DMU_OBJECT_IS_SPECIAL(zb->zb_object)) {
 476                 return (0);
 477         } else if (zb->zb_level == ZB_ZIL_LEVEL) {
 478                 /*
 479                  * If we are sending a non-snapshot (which is allowed on
 480                  * read-only pools), it may have a ZIL, which must be ignored.
 481                  */
 482                 return (0);
 483         } else if (BP_IS_HOLE(bp) &&
 484             zb->zb_object == DMU_META_DNODE_OBJECT) {
 485                 uint64_t span = BP_SPAN(dnp, zb->zb_level);
 486                 uint64_t dnobj = (zb->zb_blkid * span) >> DNODE_SHIFT;
 487                 err = dump_freeobjects(dsp, dnobj, span >> DNODE_SHIFT);
 488         } else if (BP_IS_HOLE(bp)) {
 489                 uint64_t span = BP_SPAN(dnp, zb->zb_level);
 490                 err = dump_free(dsp, zb->zb_object, zb->zb_blkid * span, span);
 491         } else if (zb->zb_level > 0 || type == DMU_OT_OBJSET) {
 492                 return (0);
 493         } else if (type == DMU_OT_DNODE) {
 494                 dnode_phys_t *blk;
 495                 int i;
 496                 int blksz = BP_GET_LSIZE(bp);
 497                 arc_flags_t aflags = ARC_FLAG_WAIT;
 498                 arc_buf_t *abuf;
 499
 500                 if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
 501                     ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
 502                     &aflags, zb) != 0)
 503                         return (SET_ERROR(EIO));
 504
 505                 blk = abuf->b_data;
 506                 for (i = 0; i < blksz >> DNODE_SHIFT; i++) {
 507                         uint64_t dnobj = (zb->zb_blkid <<
 508                             (DNODE_BLOCK_SHIFT - DNODE_SHIFT)) + i;
 509                         err = dump_dnode(dsp, dnobj, blk+i);
 510                         if (err != 0)
 511                                 break;
 512                 }
 513                 (void) arc_buf_remove_ref(abuf, &abuf);
 514         } else if (type == DMU_OT_SA) {
 515                 arc_flags_t aflags = ARC_FLAG_WAIT;
 516                 arc_buf_t *abuf;
 517                 int blksz = BP_GET_LSIZE(bp);
 518
 519                 if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
 520                     ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
 521                     &aflags, zb) != 0)
 522                         return (SET_ERROR(EIO));
 523
 524                 err = dump_spill(dsp, zb->zb_object, blksz, abuf->b_data);
 525                 (void) arc_buf_remove_ref(abuf, &abuf);
 526         } else if (backup_do_embed(dsp, bp)) {
 527                 /* it's an embedded level-0 block of a regular object */
 528                 int blksz = dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT;
 529                 err = dump_write_embedded(dsp, zb->zb_object,
 530                     zb->zb_blkid * blksz, blksz, bp);
 531         } else { /* it's a level-0 block of a regular object */
 532                 arc_flags_t aflags = ARC_FLAG_WAIT;
 533                 arc_buf_t *abuf;
 534                 int blksz = BP_GET_LSIZE(bp);
 535                 uint64_t offset;
 536
 537                 ASSERT3U(blksz, ==, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 538                 ASSERT0(zb->zb_level);
 539                 if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
 540                     ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
 541                     &aflags, zb) != 0) {
 542                         if (zfs_send_corrupt_data) {
 543                                 /* Send a block filled with 0x"zfs badd bloc" */
 544                                 abuf = arc_buf_alloc(spa, blksz, &abuf,
 545                                     ARC_BUFC_DATA);
 546                                 uint64_t *ptr;
 547                                 for (ptr = abuf->b_data;
 548                                     (char *)ptr < (char *)abuf->b_data + blksz;
 549                                     ptr++)
 550                                         *ptr = 0x2f5baddb10cULL;
 551                         } else {
 552                                 return (SET_ERROR(EIO));
 553                         }
 554                 }
 555
 556                 offset = zb->zb_blkid * blksz;
 557
 558                 if (!(dsp->dsa_featureflags &
 559                     DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
 560                     blksz > SPA_OLD_MAXBLOCKSIZE) {
 561                         char *buf = abuf->b_data;
 562                         while (blksz > 0 && err == 0) {
 563                                 int n = MIN(blksz, SPA_OLD_MAXBLOCKSIZE);
 564                                 err = dump_write(dsp, type, zb->zb_object,
 565                                     offset, n, NULL, buf);
 566                                 offset += n;
 567                                 buf += n;
 568                                 blksz -= n;
 569                         }
 570                 } else {
 571                         err = dump_write(dsp, type, zb->zb_object,
 572                             offset, blksz, bp, abuf->b_data);
 573                 }
 574                 (void) arc_buf_remove_ref(abuf, &abuf);
 575         }
 576
 577         ASSERT(err == 0 || err == EINTR);
 578         return (err);
 579 }
 580
 581 /*
 582  * Releases dp using the specified tag.
 583  */
 584 static int
 585 dmu_send_impl(void *tag, dsl_pool_t *dp, dsl_dataset_t *ds,
 586     zfs_bookmark_phys_t *fromzb, boolean_t is_clone, boolean_t embedok,
 587 #ifdef illumos
 588     boolean_t large_block_ok, int outfd, vnode_t *vp, offset_t *off)
 589 #else
 590     boolean_t large_block_ok, int outfd, struct file *fp, offset_t *off)
 591 #endif
 592 {
 593         objset_t *os;
 594         dmu_replay_record_t *drr;
 595         dmu_sendarg_t *dsp;
 596         int err;
 597         uint64_t fromtxg = 0;
 598         uint64_t featureflags = 0;
 599
 600         err = dmu_objset_from_ds(ds, &os);
 601         if (err != 0) {
 602                 dsl_pool_rele(dp, tag);
 603                 return (err);
 604         }
 605
 606         drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
 607         drr->drr_type = DRR_BEGIN;
 608         drr->drr_u.drr_begin.drr_magic = DMU_BACKUP_MAGIC;
 609         DMU_SET_STREAM_HDRTYPE(drr->drr_u.drr_begin.drr_versioninfo,
 610             DMU_SUBSTREAM);
 611
 612 #ifdef _KERNEL
 613         if (dmu_objset_type(os) == DMU_OST_ZFS) {
 614                 uint64_t version;
 615                 if (zfs_get_zplprop(os, ZFS_PROP_VERSION, &version) != 0) {
 616                         kmem_free(drr, sizeof (dmu_replay_record_t));
 617                         dsl_pool_rele(dp, tag);
 618                         return (SET_ERROR(EINVAL));
 619                 }
 620                 if (version >= ZPL_VERSION_SA) {
 621                         featureflags |= DMU_BACKUP_FEATURE_SA_SPILL;
 622                 }
 623         }
 624 #endif
 625
 626         if (large_block_ok && ds->ds_large_blocks)
 627                 featureflags |= DMU_BACKUP_FEATURE_LARGE_BLOCKS;
 628         if (embedok &&
 629             spa_feature_is_active(dp->dp_spa, SPA_FEATURE_EMBEDDED_DATA)) {
 630                 featureflags |= DMU_BACKUP_FEATURE_EMBED_DATA;
 631                 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_LZ4_COMPRESS))
 632                         featureflags |= DMU_BACKUP_FEATURE_EMBED_DATA_LZ4;
 633         } else {
 634                 embedok = B_FALSE;
 635         }
 636
 637         DMU_SET_FEATUREFLAGS(drr->drr_u.drr_begin.drr_versioninfo,
 638             featureflags);
 639
 640         drr->drr_u.drr_begin.drr_creation_time =
 641             dsl_dataset_phys(ds)->ds_creation_time;
 642         drr->drr_u.drr_begin.drr_type = dmu_objset_type(os);
 643         if (is_clone)
 644                 drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CLONE;
 645         drr->drr_u.drr_begin.drr_toguid = dsl_dataset_phys(ds)->ds_guid;
 646         if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET)
 647                 drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CI_DATA;
 648
 649         if (fromzb != NULL) {
 650                 drr->drr_u.drr_begin.drr_fromguid = fromzb->zbm_guid;
 651                 fromtxg = fromzb->zbm_creation_txg;
 652         }
 653         dsl_dataset_name(ds, drr->drr_u.drr_begin.drr_toname);
 654         if (!ds->ds_is_snapshot) {
 655                 (void) strlcat(drr->drr_u.drr_begin.drr_toname, "@--head--",
 656                     sizeof (drr->drr_u.drr_begin.drr_toname));
 657         }
 658
 659         dsp = kmem_zalloc(sizeof (dmu_sendarg_t), KM_SLEEP);
 660
 661         dsp->dsa_drr = drr;
 662         dsp->dsa_outfd = outfd;
 663         dsp->dsa_proc = curproc;
 664         dsp->dsa_td = curthread;
 665         dsp->dsa_fp = fp;
 666         dsp->dsa_os = os;
 667         dsp->dsa_off = off;
 668         dsp->dsa_toguid = dsl_dataset_phys(ds)->ds_guid;
 669         dsp->dsa_pending_op = PENDING_NONE;
 670         dsp->dsa_incremental = (fromzb != NULL);
 671         dsp->dsa_featureflags = featureflags;
 672
 673         mutex_enter(&ds->ds_sendstream_lock);
 674         list_insert_head(&ds->ds_sendstreams, dsp);
 675         mutex_exit(&ds->ds_sendstream_lock);
 676
 677         dsl_dataset_long_hold(ds, FTAG);
 678         dsl_pool_rele(dp, tag);
 679
 680         if (dump_record(dsp, NULL, 0) != 0) {
 681                 err = dsp->dsa_err;
 682                 goto out;
 683         }
 684
 685         err = traverse_dataset(ds, fromtxg, TRAVERSE_PRE | TRAVERSE_PREFETCH,
 686             backup_cb, dsp);
 687
 688         if (dsp->dsa_pending_op != PENDING_NONE)
 689                 if (dump_record(dsp, NULL, 0) != 0)
 690                         err = SET_ERROR(EINTR);
 691
 692         if (err != 0) {
 693                 if (err == EINTR && dsp->dsa_err != 0)
 694                         err = dsp->dsa_err;
 695                 goto out;
 696         }
 697
 698         bzero(drr, sizeof (dmu_replay_record_t));
 699         drr->drr_type = DRR_END;
 700         drr->drr_u.drr_end.drr_checksum = dsp->dsa_zc;
 701         drr->drr_u.drr_end.drr_toguid = dsp->dsa_toguid;
 702
 703         if (dump_record(dsp, NULL, 0) != 0) {
 704                 err = dsp->dsa_err;
 705                 goto out;
 706         }
 707
 708 out:
 709         mutex_enter(&ds->ds_sendstream_lock);
 710         list_remove(&ds->ds_sendstreams, dsp);
 711         mutex_exit(&ds->ds_sendstream_lock);
 712
 713         kmem_free(drr, sizeof (dmu_replay_record_t));
 714         kmem_free(dsp, sizeof (dmu_sendarg_t));
 715
 716         dsl_dataset_long_rele(ds, FTAG);
 717
 718         return (err);
 719 }
 720
 721 int
 722 dmu_send_obj(const char *pool, uint64_t tosnap, uint64_t fromsnap,
 723     boolean_t embedok, boolean_t large_block_ok,
 724 #ifdef illumos
 725     int outfd, vnode_t *vp, offset_t *off)
 726 #else
 727     int outfd, struct file *fp, offset_t *off)
 728 #endif
 729 {
 730         dsl_pool_t *dp;
 731         dsl_dataset_t *ds;
 732         dsl_dataset_t *fromds = NULL;
 733         int err;
 734
 735         err = dsl_pool_hold(pool, FTAG, &dp);
 736         if (err != 0)
 737                 return (err);
 738
 739         err = dsl_dataset_hold_obj(dp, tosnap, FTAG, &ds);
 740         if (err != 0) {
 741                 dsl_pool_rele(dp, FTAG);
 742                 return (err);
 743         }
 744
 745         if (fromsnap != 0) {
 746                 zfs_bookmark_phys_t zb;
 747                 boolean_t is_clone;
 748
 749                 err = dsl_dataset_hold_obj(dp, fromsnap, FTAG, &fromds);
 750                 if (err != 0) {
 751                         dsl_dataset_rele(ds, FTAG);
 752                         dsl_pool_rele(dp, FTAG);
 753                         return (err);
 754                 }
 755                 if (!dsl_dataset_is_before(ds, fromds, 0))
 756                         err = SET_ERROR(EXDEV);
 757                 zb.zbm_creation_time =
 758                     dsl_dataset_phys(fromds)->ds_creation_time;
 759                 zb.zbm_creation_txg = dsl_dataset_phys(fromds)->ds_creation_txg;
 760                 zb.zbm_guid = dsl_dataset_phys(fromds)->ds_guid;
 761                 is_clone = (fromds->ds_dir != ds->ds_dir);
 762                 dsl_dataset_rele(fromds, FTAG);
 763                 err = dmu_send_impl(FTAG, dp, ds, &zb, is_clone,
 764                     embedok, large_block_ok, outfd, fp, off);
 765         } else {
 766                 err = dmu_send_impl(FTAG, dp, ds, NULL, B_FALSE,
 767                     embedok, large_block_ok, outfd, fp, off);
 768         }
 769         dsl_dataset_rele(ds, FTAG);
 770         return (err);
 771 }
 772
 773 int
 774 dmu_send(const char *tosnap, const char *fromsnap,
 775     boolean_t embedok, boolean_t large_block_ok,
 776 #ifdef illumos
 777     int outfd, vnode_t *vp, offset_t *off)
 778 #else
 779     int outfd, struct file *fp, offset_t *off)
 780 #endif
 781 {
 782         dsl_pool_t *dp;
 783         dsl_dataset_t *ds;
 784         int err;
 785         boolean_t owned = B_FALSE;
 786
 787         if (fromsnap != NULL && strpbrk(fromsnap, "@#") == NULL)
 788                 return (SET_ERROR(EINVAL));
 789
 790         err = dsl_pool_hold(tosnap, FTAG, &dp);
 791         if (err != 0)
 792                 return (err);
 793
 794         if (strchr(tosnap, '@') == NULL && spa_writeable(dp->dp_spa)) {
 795                 /*
 796                  * We are sending a filesystem or volume.  Ensure
 797                  * that it doesn't change by owning the dataset.
 798                  */
 799                 err = dsl_dataset_own(dp, tosnap, FTAG, &ds);
 800                 owned = B_TRUE;
 801         } else {
 802                 err = dsl_dataset_hold(dp, tosnap, FTAG, &ds);
 803         }
 804         if (err != 0) {
 805                 dsl_pool_rele(dp, FTAG);
 806                 return (err);
 807         }
 808
 809         if (fromsnap != NULL) {
 810                 zfs_bookmark_phys_t zb;
 811                 boolean_t is_clone = B_FALSE;
 812                 int fsnamelen = strchr(tosnap, '@') - tosnap;
 813
 814                 /*
 815                  * If the fromsnap is in a different filesystem, then
 816                  * mark the send stream as a clone.
 817                  */
 818                 if (strncmp(tosnap, fromsnap, fsnamelen) != 0 ||
 819                     (fromsnap[fsnamelen] != '@' &&
 820                     fromsnap[fsnamelen] != '#')) {
 821                         is_clone = B_TRUE;
 822                 }
 823
 824                 if (strchr(fromsnap, '@')) {
 825                         dsl_dataset_t *fromds;
 826                         err = dsl_dataset_hold(dp, fromsnap, FTAG, &fromds);
 827                         if (err == 0) {
 828                                 if (!dsl_dataset_is_before(ds, fromds, 0))
 829                                         err = SET_ERROR(EXDEV);
 830                                 zb.zbm_creation_time =
 831                                     dsl_dataset_phys(fromds)->ds_creation_time;
 832                                 zb.zbm_creation_txg =
 833                                     dsl_dataset_phys(fromds)->ds_creation_txg;
 834                                 zb.zbm_guid = dsl_dataset_phys(fromds)->ds_guid;
 835                                 is_clone = (ds->ds_dir != fromds->ds_dir);
 836                                 dsl_dataset_rele(fromds, FTAG);
 837                         }
 838                 } else {
 839                         err = dsl_bookmark_lookup(dp, fromsnap, ds, &zb);
 840                 }
 841                 if (err != 0) {
 842                         dsl_dataset_rele(ds, FTAG);
 843                         dsl_pool_rele(dp, FTAG);
 844                         return (err);
 845                 }
 846                 err = dmu_send_impl(FTAG, dp, ds, &zb, is_clone,
 847                     embedok, large_block_ok, outfd, fp, off);
 848         } else {
 849                 err = dmu_send_impl(FTAG, dp, ds, NULL, B_FALSE,
 850                     embedok, large_block_ok, outfd, fp, off);
 851         }
 852         if (owned)
 853                 dsl_dataset_disown(ds, FTAG);
 854         else
 855                 dsl_dataset_rele(ds, FTAG);
 856         return (err);
 857 }
 858
 859 static int
 860 dmu_adjust_send_estimate_for_indirects(dsl_dataset_t *ds, uint64_t size,
 861     uint64_t *sizep)
 862 {
 863         int err;
 864         /*
 865          * Assume that space (both on-disk and in-stream) is dominated by
 866          * data.  We will adjust for indirect blocks and the copies property,
 867          * but ignore per-object space used (eg, dnodes and DRR_OBJECT records).
 868          */
 869
 870         /*
 871          * Subtract out approximate space used by indirect blocks.
 872          * Assume most space is used by data blocks (non-indirect, non-dnode).
 873          * Assume all blocks are recordsize.  Assume ditto blocks and
 874          * internal fragmentation counter out compression.
 875          *
 876          * Therefore, space used by indirect blocks is sizeof(blkptr_t) per
 877          * block, which we observe in practice.
 878          */
 879         uint64_t recordsize;
 880         err = dsl_prop_get_int_ds(ds, "recordsize", &recordsize);
 881         if (err != 0)
 882                 return (err);
 883         size -= size / recordsize * sizeof (blkptr_t);
 884
 885         /* Add in the space for the record associated with each block. */
 886         size += size / recordsize * sizeof (dmu_replay_record_t);
 887
 888         *sizep = size;
 889
 890         return (0);
 891 }
 892
 893 int
 894 dmu_send_estimate(dsl_dataset_t *ds, dsl_dataset_t *fromds, uint64_t *sizep)
 895 {
 896         dsl_pool_t *dp = ds->ds_dir->dd_pool;
 897         int err;
 898         uint64_t size;
 899
 900         ASSERT(dsl_pool_config_held(dp));
 901
 902         /* tosnap must be a snapshot */
 903         if (!ds->ds_is_snapshot)
 904                 return (SET_ERROR(EINVAL));
 905
 906         /* fromsnap, if provided, must be a snapshot */
 907         if (fromds != NULL && !fromds->ds_is_snapshot)
 908                 return (SET_ERROR(EINVAL));
 909
 910         /*
 911          * fromsnap must be an earlier snapshot from the same fs as tosnap,
 912          * or the origin's fs.
 913          */
 914         if (fromds != NULL && !dsl_dataset_is_before(ds, fromds, 0))
 915                 return (SET_ERROR(EXDEV));
 916
 917         /* Get uncompressed size estimate of changed data. */
 918         if (fromds == NULL) {
 919                 size = dsl_dataset_phys(ds)->ds_uncompressed_bytes;
 920         } else {
 921                 uint64_t used, comp;
 922                 err = dsl_dataset_space_written(fromds, ds,
 923                     &used, &comp, &size);
 924                 if (err != 0)
 925                         return (err);
 926         }
 927
 928         err = dmu_adjust_send_estimate_for_indirects(ds, size, sizep);
 929         return (err);
 930 }
 931
 932 /*
 933  * Simple callback used to traverse the blocks of a snapshot and sum their
 934  * uncompressed size
 935  */
 936 /* ARGSUSED */
 937 static int
 938 dmu_calculate_send_traversal(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
 939     const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
 940 {
 941         uint64_t *spaceptr = arg;
 942         if (bp != NULL && !BP_IS_HOLE(bp)) {
 943                 *spaceptr += BP_GET_UCSIZE(bp);
 944         }
 945         return (0);
 946 }
 947
 948 /*
 949  * Given a desination snapshot and a TXG, calculate the approximate size of a
 950  * send stream sent from that TXG. from_txg may be zero, indicating that the
 951  * whole snapshot will be sent.
 952  */
 953 int
 954 dmu_send_estimate_from_txg(dsl_dataset_t *ds, uint64_t from_txg,
 955     uint64_t *sizep)
 956 {
 957         dsl_pool_t *dp = ds->ds_dir->dd_pool;
 958         int err;
 959         uint64_t size = 0;
 960
 961         ASSERT(dsl_pool_config_held(dp));
 962
 963         /* tosnap must be a snapshot */
 964         if (!dsl_dataset_is_snapshot(ds))
 965                 return (SET_ERROR(EINVAL));
 966
 967         /* verify that from_txg is before the provided snapshot was taken */
 968         if (from_txg >= dsl_dataset_phys(ds)->ds_creation_txg) {
 969                 return (SET_ERROR(EXDEV));
 970         }
 971
 972         /*
 973          * traverse the blocks of the snapshot with birth times after
 974          * from_txg, summing their uncompressed size
 975          */
 976         err = traverse_dataset(ds, from_txg, TRAVERSE_POST,
 977             dmu_calculate_send_traversal, &size);
 978         if (err)
 979                 return (err);
 980
 981         err = dmu_adjust_send_estimate_for_indirects(ds, size, sizep);
 982         return (err);
 983 }
 984
 985 typedef struct dmu_recv_begin_arg {
 986         const char *drba_origin;
 987         dmu_recv_cookie_t *drba_cookie;
 988         cred_t *drba_cred;
 989         uint64_t drba_snapobj;
 990 } dmu_recv_begin_arg_t;
 991
 992 static int
 993 recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
 994     uint64_t fromguid)
 995 {
 996         uint64_t val;
 997         int error;
 998         dsl_pool_t *dp = ds->ds_dir->dd_pool;
 999
1000         /* temporary clone name must not exist */
1001         error = zap_lookup(dp->dp_meta_objset,
1002             dsl_dir_phys(ds->ds_dir)->dd_child_dir_zapobj, recv_clone_name,
1003             8, 1, &val);
1004         if (error != ENOENT)
1005                 return (error == 0 ? EBUSY : error);
1006
1007         /* new snapshot name must not exist */
1008         error = zap_lookup(dp->dp_meta_objset,
1009             dsl_dataset_phys(ds)->ds_snapnames_zapobj,
1010             drba->drba_cookie->drc_tosnap, 8, 1, &val);
1011         if (error != ENOENT)
1012                 return (error == 0 ? EEXIST : error);
1013
1014         /*
1015          * Check snapshot limit before receiving. We'll recheck again at the
1016          * end, but might as well abort before receiving if we're already over
1017          * the limit.
1018          *
1019          * Note that we do not check the file system limit with
1020          * dsl_dir_fscount_check because the temporary %clones don't count
1021          * against that limit.
1022          */
1023         error = dsl_fs_ss_limit_check(ds->ds_dir, 1, ZFS_PROP_SNAPSHOT_LIMIT,
1024             NULL, drba->drba_cred);
1025         if (error != 0)
1026                 return (error);
1027
1028         if (fromguid != 0) {
1029                 dsl_dataset_t *snap;
1030                 uint64_t obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
1031
1032                 /* Find snapshot in this dir that matches fromguid. */
1033                 while (obj != 0) {
1034                         error = dsl_dataset_hold_obj(dp, obj, FTAG,
1035                             &snap);
1036                         if (error != 0)
1037                                 return (SET_ERROR(ENODEV));
1038                         if (snap->ds_dir != ds->ds_dir) {
1039                                 dsl_dataset_rele(snap, FTAG);
1040                                 return (SET_ERROR(ENODEV));
1041                         }
1042                         if (dsl_dataset_phys(snap)->ds_guid == fromguid)
1043                                 break;
1044                         obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
1045                         dsl_dataset_rele(snap, FTAG);
1046                 }
1047                 if (obj == 0)
1048                         return (SET_ERROR(ENODEV));
1049
1050                 if (drba->drba_cookie->drc_force) {
1051                         drba->drba_snapobj = obj;
1052                 } else {
1053                         /*
1054                          * If we are not forcing, there must be no
1055                          * changes since fromsnap.
1056                          */
1057                         if (dsl_dataset_modified_since_snap(ds, snap)) {
1058                                 dsl_dataset_rele(snap, FTAG);
1059                                 return (SET_ERROR(ETXTBSY));
1060                         }
1061                         drba->drba_snapobj = ds->ds_prev->ds_object;
1062                 }
1063
1064                 dsl_dataset_rele(snap, FTAG);
1065         } else {
1066                 /* if full, then must be forced */
1067                 if (!drba->drba_cookie->drc_force)
1068                         return (SET_ERROR(EEXIST));
1069                 /* start from $ORIGIN@$ORIGIN, if supported */
1070                 drba->drba_snapobj = dp->dp_origin_snap != NULL ?
1071                     dp->dp_origin_snap->ds_object : 0;
1072         }
1073
1074         return (0);
1075
1076 }
1077
1078 static int
1079 dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
1080 {
1081         dmu_recv_begin_arg_t *drba = arg;
1082         dsl_pool_t *dp = dmu_tx_pool(tx);
1083         struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
1084         uint64_t fromguid = drrb->drr_fromguid;
1085         int flags = drrb->drr_flags;
1086         int error;
1087         uint64_t featureflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo);
1088         dsl_dataset_t *ds;
1089         const char *tofs = drba->drba_cookie->drc_tofs;
1090
1091         /* already checked */
1092         ASSERT3U(drrb->drr_magic, ==, DMU_BACKUP_MAGIC);
1093
1094         if (DMU_GET_STREAM_HDRTYPE(drrb->drr_versioninfo) ==
1095             DMU_COMPOUNDSTREAM ||
1096             drrb->drr_type >= DMU_OST_NUMTYPES ||
1097             ((flags & DRR_FLAG_CLONE) && drba->drba_origin == NULL))
1098                 return (SET_ERROR(EINVAL));
1099
1100         /* Verify pool version supports SA if SA_SPILL feature set */
1101         if ((featureflags & DMU_BACKUP_FEATURE_SA_SPILL) &&
1102             spa_version(dp->dp_spa) < SPA_VERSION_SA)
1103                 return (SET_ERROR(ENOTSUP));
1104
1105         /*
1106          * The receiving code doesn't know how to translate a WRITE_EMBEDDED
1107          * record to a plan WRITE record, so the pool must have the
1108          * EMBEDDED_DATA feature enabled if the stream has WRITE_EMBEDDED
1109          * records.  Same with WRITE_EMBEDDED records that use LZ4 compression.
1110          */
1111         if ((featureflags & DMU_BACKUP_FEATURE_EMBED_DATA) &&
1112             !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_EMBEDDED_DATA))
1113                 return (SET_ERROR(ENOTSUP));
1114         if ((featureflags & DMU_BACKUP_FEATURE_EMBED_DATA_LZ4) &&
1115             !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LZ4_COMPRESS))
1116                 return (SET_ERROR(ENOTSUP));
1117
1118         /*
1119          * The receiving code doesn't know how to translate large blocks
1120          * to smaller ones, so the pool must have the LARGE_BLOCKS
1121          * feature enabled if the stream has LARGE_BLOCKS.
1122          */
1123         if ((featureflags & DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
1124             !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LARGE_BLOCKS))
1125                 return (SET_ERROR(ENOTSUP));
1126
1127         error = dsl_dataset_hold(dp, tofs, FTAG, &ds);
1128         if (error == 0) {
1129                 /* target fs already exists; recv into temp clone */
1130
1131                 /* Can't recv a clone into an existing fs */
1132                 if (flags & DRR_FLAG_CLONE) {
1133                         dsl_dataset_rele(ds, FTAG);
1134                         return (SET_ERROR(EINVAL));
1135                 }
1136
1137                 error = recv_begin_check_existing_impl(drba, ds, fromguid);
1138                 dsl_dataset_rele(ds, FTAG);
1139         } else if (error == ENOENT) {
1140                 /* target fs does not exist; must be a full backup or clone */
1141                 char buf[MAXNAMELEN];
1142
1143                 /*
1144                  * If it's a non-clone incremental, we are missing the
1145                  * target fs, so fail the recv.
1146                  */
1147                 if (fromguid != 0 && !(flags & DRR_FLAG_CLONE))
1148                         return (SET_ERROR(ENOENT));
1149
1150                 /* Open the parent of tofs */
1151                 ASSERT3U(strlen(tofs), <, MAXNAMELEN);
1152                 (void) strlcpy(buf, tofs, strrchr(tofs, '/') - tofs + 1);
1153                 error = dsl_dataset_hold(dp, buf, FTAG, &ds);
1154                 if (error != 0)
1155                         return (error);
1156
1157                 /*
1158                  * Check filesystem and snapshot limits before receiving. We'll
1159                  * recheck snapshot limits again at the end (we create the
1160                  * filesystems and increment those counts during begin_sync).
1161                  */
1162                 error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
1163                     ZFS_PROP_FILESYSTEM_LIMIT, NULL, drba->drba_cred);
1164                 if (error != 0) {
1165                         dsl_dataset_rele(ds, FTAG);
1166                         return (error);
1167                 }
1168
1169                 error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
1170                     ZFS_PROP_SNAPSHOT_LIMIT, NULL, drba->drba_cred);
1171                 if (error != 0) {
1172                         dsl_dataset_rele(ds, FTAG);
1173                         return (error);
1174                 }
1175
1176                 if (drba->drba_origin != NULL) {
1177                         dsl_dataset_t *origin;
1178                         error = dsl_dataset_hold(dp, drba->drba_origin,
1179                             FTAG, &origin);
1180                         if (error != 0) {
1181                                 dsl_dataset_rele(ds, FTAG);
1182                                 return (error);
1183                         }
1184                         if (!origin->ds_is_snapshot) {
1185                                 dsl_dataset_rele(origin, FTAG);
1186                                 dsl_dataset_rele(ds, FTAG);
1187                                 return (SET_ERROR(EINVAL));
1188                         }
1189                         if (dsl_dataset_phys(origin)->ds_guid != fromguid) {
1190                                 dsl_dataset_rele(origin, FTAG);
1191                                 dsl_dataset_rele(ds, FTAG);
1192                                 return (SET_ERROR(ENODEV));
1193                         }
1194                         dsl_dataset_rele(origin, FTAG);
1195                 }
1196                 dsl_dataset_rele(ds, FTAG);
1197                 error = 0;
1198         }
1199         return (error);
1200 }
1201
1202 static void
1203 dmu_recv_begin_sync(void *arg, dmu_tx_t *tx)
1204 {
1205         dmu_recv_begin_arg_t *drba = arg;
1206         dsl_pool_t *dp = dmu_tx_pool(tx);
1207         struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
1208         const char *tofs = drba->drba_cookie->drc_tofs;
1209         dsl_dataset_t *ds, *newds;
1210         uint64_t dsobj;
1211         int error;
1212         uint64_t crflags;
1213
1214         crflags = (drrb->drr_flags & DRR_FLAG_CI_DATA) ?
1215             DS_FLAG_CI_DATASET : 0;
1216
1217         error = dsl_dataset_hold(dp, tofs, FTAG, &ds);
1218         if (error == 0) {
1219                 /* create temporary clone */
1220                 dsl_dataset_t *snap = NULL;
1221                 if (drba->drba_snapobj != 0) {
1222                         VERIFY0(dsl_dataset_hold_obj(dp,
1223                             drba->drba_snapobj, FTAG, &snap));
1224                 }
1225                 dsobj = dsl_dataset_create_sync(ds->ds_dir, recv_clone_name,
1226                     snap, crflags, drba->drba_cred, tx);
1227                 if (drba->drba_snapobj != 0)
1228                         dsl_dataset_rele(snap, FTAG);
1229                 dsl_dataset_rele(ds, FTAG);
1230         } else {
1231                 dsl_dir_t *dd;
1232                 const char *tail;
1233                 dsl_dataset_t *origin = NULL;
1234
1235                 VERIFY0(dsl_dir_hold(dp, tofs, FTAG, &dd, &tail));
1236
1237                 if (drba->drba_origin != NULL) {
1238                         VERIFY0(dsl_dataset_hold(dp, drba->drba_origin,
1239                             FTAG, &origin));
1240                 }
1241
1242                 /* Create new dataset. */
1243                 dsobj = dsl_dataset_create_sync(dd,
1244                     strrchr(tofs, '/') + 1,
1245                     origin, crflags, drba->drba_cred, tx);
1246                 if (origin != NULL)
1247                         dsl_dataset_rele(origin, FTAG);
1248                 dsl_dir_rele(dd, FTAG);
1249                 drba->drba_cookie->drc_newfs = B_TRUE;
1250         }
1251         VERIFY0(dsl_dataset_own_obj(dp, dsobj, dmu_recv_tag, &newds));
1252
1253         if ((DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo) &
1254             DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
1255             !newds->ds_large_blocks) {
1256                 dsl_dataset_activate_large_blocks_sync_impl(dsobj, tx);
1257                 newds->ds_large_blocks = B_TRUE;
1258         }
1259
1260         dmu_buf_will_dirty(newds->ds_dbuf, tx);
1261         dsl_dataset_phys(newds)->ds_flags |= DS_FLAG_INCONSISTENT;
1262
1263         /*
1264          * If we actually created a non-clone, we need to create the
1265          * objset in our new dataset.
1266          */
1267         if (BP_IS_HOLE(dsl_dataset_get_blkptr(newds))) {
1268                 (void) dmu_objset_create_impl(dp->dp_spa,
1269                     newds, dsl_dataset_get_blkptr(newds), drrb->drr_type, tx);
1270         }
1271
1272         drba->drba_cookie->drc_ds = newds;
1273
1274         spa_history_log_internal_ds(newds, "receive", tx, "");
1275 }
1276
1277 /*
1278  * NB: callers *MUST* call dmu_recv_stream() if dmu_recv_begin()
1279  * succeeds; otherwise we will leak the holds on the datasets.
1280  */
1281 int
1282 dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
1283     boolean_t force, char *origin, dmu_recv_cookie_t *drc)
1284 {
1285         dmu_recv_begin_arg_t drba = { 0 };
1286         dmu_replay_record_t *drr;
1287
1288         bzero(drc, sizeof (dmu_recv_cookie_t));
1289         drc->drc_drrb = drrb;
1290         drc->drc_tosnap = tosnap;
1291         drc->drc_tofs = tofs;
1292         drc->drc_force = force;
1293         drc->drc_cred = CRED();
1294
1295         if (drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC))
1296                 drc->drc_byteswap = B_TRUE;
1297         else if (drrb->drr_magic != DMU_BACKUP_MAGIC)
1298                 return (SET_ERROR(EINVAL));
1299
1300         drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
1301         drr->drr_type = DRR_BEGIN;
1302         drr->drr_u.drr_begin = *drc->drc_drrb;
1303         if (drc->drc_byteswap) {
1304                 fletcher_4_incremental_byteswap(drr,
1305                     sizeof (dmu_replay_record_t), &drc->drc_cksum);
1306         } else {
1307                 fletcher_4_incremental_native(drr,
1308                     sizeof (dmu_replay_record_t), &drc->drc_cksum);
1309         }
1310         kmem_free(drr, sizeof (dmu_replay_record_t));
1311
1312         if (drc->drc_byteswap) {
1313                 drrb->drr_magic = BSWAP_64(drrb->drr_magic);
1314                 drrb->drr_versioninfo = BSWAP_64(drrb->drr_versioninfo);
1315                 drrb->drr_creation_time = BSWAP_64(drrb->drr_creation_time);
1316                 drrb->drr_type = BSWAP_32(drrb->drr_type);
1317                 drrb->drr_toguid = BSWAP_64(drrb->drr_toguid);
1318                 drrb->drr_fromguid = BSWAP_64(drrb->drr_fromguid);
1319         }
1320
1321         drba.drba_origin = origin;
1322         drba.drba_cookie = drc;
1323         drba.drba_cred = CRED();
1324
1325         return (dsl_sync_task(tofs, dmu_recv_begin_check, dmu_recv_begin_sync,
1326             &drba, 5, ZFS_SPACE_CHECK_NORMAL));
1327 }
1328
1329 struct restorearg {
1330         objset_t *os;
1331         int err;
1332         boolean_t byteswap;
1333         kthread_t *td;
1334         struct file *fp;
1335         uint64_t voff;
1336         int bufsize; /* amount of memory allocated for buf */
1337
1338         dmu_replay_record_t *drr;
1339         dmu_replay_record_t *next_drr;
1340         char *buf;
1341         zio_cksum_t cksum;
1342         zio_cksum_t prev_cksum;
1343
1344         avl_tree_t *guid_to_ds_map;
1345 };
1346
1347 typedef struct guid_map_entry {
1348         uint64_t        guid;
1349         dsl_dataset_t   *gme_ds;
1350         avl_node_t      avlnode;
1351 } guid_map_entry_t;
1352
1353 static int
1354 guid_compare(const void *arg1, const void *arg2)
1355 {
1356         const guid_map_entry_t *gmep1 = arg1;
1357         const guid_map_entry_t *gmep2 = arg2;
1358
1359         if (gmep1->guid < gmep2->guid)
1360                 return (-1);
1361         else if (gmep1->guid > gmep2->guid)
1362                 return (1);
1363         return (0);
1364 }
1365
1366 static void
1367 free_guid_map_onexit(void *arg)
1368 {
1369         avl_tree_t *ca = arg;
1370         void *cookie = NULL;
1371         guid_map_entry_t *gmep;
1372
1373         while ((gmep = avl_destroy_nodes(ca, &cookie)) != NULL) {
1374                 dsl_dataset_long_rele(gmep->gme_ds, gmep);
1375                 dsl_dataset_rele(gmep->gme_ds, gmep);
1376                 kmem_free(gmep, sizeof (guid_map_entry_t));
1377         }
1378         avl_destroy(ca);
1379         kmem_free(ca, sizeof (avl_tree_t));
1380 }
1381
1382 static int
1383 restore_bytes(struct restorearg *ra, void *buf, int len, off_t off, ssize_t *resid)
1384 {
1385         struct uio auio;
1386         struct iovec aiov;
1387         int error;
1388
1389         aiov.iov_base = buf;
1390         aiov.iov_len = len;
1391         auio.uio_iov = &aiov;
1392         auio.uio_iovcnt = 1;
1393         auio.uio_resid = len;
1394         auio.uio_segflg = UIO_SYSSPACE;
1395         auio.uio_rw = UIO_READ;
1396         auio.uio_offset = off;
1397         auio.uio_td = ra->td;
1398 #ifdef _KERNEL
1399         error = fo_read(ra->fp, &auio, ra->td->td_ucred, FOF_OFFSET, ra->td);
1400 #else
1401         fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__);
1402         error = EOPNOTSUPP;
1403 #endif
1404         *resid = auio.uio_resid;
1405         return (error);
1406 }
1407
1408 static int
1409 restore_read(struct restorearg *ra, int len, void *buf)
1410 {
1411         int done = 0;
1412
1413         /* some things will require 8-byte alignment, so everything must */
1414         ASSERT0(len % 8);
1415         ASSERT3U(len, <=, ra->bufsize);
1416
1417         while (done < len) {
1418                 ssize_t resid;
1419
1420                 ra->err = restore_bytes(ra, buf + done,
1421                     len - done, ra->voff, &resid);
1422
1423                 if (resid == len - done)
1424                         ra->err = SET_ERROR(EINVAL);
1425                 ra->voff += len - done - resid;
1426                 done = len - resid;
1427                 if (ra->err != 0)
1428                         return (ra->err);
1429         }
1430
1431         ASSERT3U(done, ==, len);
1432         return (0);
1433 }
1434
1435 static void
1436 byteswap_record(dmu_replay_record_t *drr)
1437 {
1438 #define DO64(X) (drr->drr_u.X = BSWAP_64(drr->drr_u.X))
1439 #define DO32(X) (drr->drr_u.X = BSWAP_32(drr->drr_u.X))
1440         drr->drr_type = BSWAP_32(drr->drr_type);
1441         drr->drr_payloadlen = BSWAP_32(drr->drr_payloadlen);
1442
1443         switch (drr->drr_type) {
1444         case DRR_BEGIN:
1445                 DO64(drr_begin.drr_magic);
1446                 DO64(drr_begin.drr_versioninfo);
1447                 DO64(drr_begin.drr_creation_time);
1448                 DO32(drr_begin.drr_type);
1449                 DO32(drr_begin.drr_flags);
1450                 DO64(drr_begin.drr_toguid);
1451                 DO64(drr_begin.drr_fromguid);
1452                 break;
1453         case DRR_OBJECT:
1454                 DO64(drr_object.drr_object);
1455                 DO32(drr_object.drr_type);
1456                 DO32(drr_object.drr_bonustype);
1457                 DO32(drr_object.drr_blksz);
1458                 DO32(drr_object.drr_bonuslen);
1459                 DO64(drr_object.drr_toguid);
1460                 break;
1461         case DRR_FREEOBJECTS:
1462                 DO64(drr_freeobjects.drr_firstobj);
1463                 DO64(drr_freeobjects.drr_numobjs);
1464                 DO64(drr_freeobjects.drr_toguid);
1465                 break;
1466         case DRR_WRITE:
1467                 DO64(drr_write.drr_object);
1468                 DO32(drr_write.drr_type);
1469                 DO64(drr_write.drr_offset);
1470                 DO64(drr_write.drr_length);
1471                 DO64(drr_write.drr_toguid);
1472                 ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_write.drr_key.ddk_cksum);
1473                 DO64(drr_write.drr_key.ddk_prop);
1474                 break;
1475         case DRR_WRITE_BYREF:
1476                 DO64(drr_write_byref.drr_object);
1477                 DO64(drr_write_byref.drr_offset);
1478                 DO64(drr_write_byref.drr_length);
1479                 DO64(drr_write_byref.drr_toguid);
1480                 DO64(drr_write_byref.drr_refguid);
1481                 DO64(drr_write_byref.drr_refobject);
1482                 DO64(drr_write_byref.drr_refoffset);
1483                 ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_write_byref.
1484                     drr_key.ddk_cksum);
1485                 DO64(drr_write_byref.drr_key.ddk_prop);
1486                 break;
1487         case DRR_WRITE_EMBEDDED:
1488                 DO64(drr_write_embedded.drr_object);
1489                 DO64(drr_write_embedded.drr_offset);
1490                 DO64(drr_write_embedded.drr_length);
1491                 DO64(drr_write_embedded.drr_toguid);
1492                 DO32(drr_write_embedded.drr_lsize);
1493                 DO32(drr_write_embedded.drr_psize);
1494                 break;
1495         case DRR_FREE:
1496                 DO64(drr_free.drr_object);
1497                 DO64(drr_free.drr_offset);
1498                 DO64(drr_free.drr_length);
1499                 DO64(drr_free.drr_toguid);
1500                 break;
1501         case DRR_SPILL:
1502                 DO64(drr_spill.drr_object);
1503                 DO64(drr_spill.drr_length);
1504                 DO64(drr_spill.drr_toguid);
1505                 break;
1506         case DRR_END:
1507                 DO64(drr_end.drr_toguid);
1508                 ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_end.drr_checksum);
1509                 break;
1510         }
1511
1512         if (drr->drr_type != DRR_BEGIN) {
1513                 ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_checksum.drr_checksum);
1514         }
1515
1516 #undef DO64
1517 #undef DO32
1518 }
1519
1520 static inline uint8_t
1521 deduce_nblkptr(dmu_object_type_t bonus_type, uint64_t bonus_size)
1522 {
1523         if (bonus_type == DMU_OT_SA) {
1524                 return (1);
1525         } else {
1526                 return (1 +
1527                     ((DN_MAX_BONUSLEN - bonus_size) >> SPA_BLKPTRSHIFT));
1528         }
1529 }
1530
1531 static int
1532 restore_object(struct restorearg *ra, struct drr_object *drro, void *data)
1533 {
1534         dmu_object_info_t doi;
1535         dmu_tx_t *tx;
1536         uint64_t object;
1537         int err;
1538
1539         if (drro->drr_type == DMU_OT_NONE ||
1540             !DMU_OT_IS_VALID(drro->drr_type) ||
1541             !DMU_OT_IS_VALID(drro->drr_bonustype) ||
1542             drro->drr_checksumtype >= ZIO_CHECKSUM_FUNCTIONS ||
1543             drro->drr_compress >= ZIO_COMPRESS_FUNCTIONS ||
1544             P2PHASE(drro->drr_blksz, SPA_MINBLOCKSIZE) ||
1545             drro->drr_blksz < SPA_MINBLOCKSIZE ||
1546             drro->drr_blksz > spa_maxblocksize(dmu_objset_spa(ra->os)) ||
1547             drro->drr_bonuslen > DN_MAX_BONUSLEN) {
1548                 return (SET_ERROR(EINVAL));
1549         }
1550
1551         err = dmu_object_info(ra->os, drro->drr_object, &doi);
1552
1553         if (err != 0 && err != ENOENT)
1554                 return (SET_ERROR(EINVAL));
1555         object = err == 0 ? drro->drr_object : DMU_NEW_OBJECT;
1556
1557         /*
1558          * If we are losing blkptrs or changing the block size this must
1559          * be a new file instance.  We must clear out the previous file
1560          * contents before we can change this type of metadata in the dnode.
1561          */
1562         if (err == 0) {
1563                 int nblkptr;
1564
1565                 nblkptr = deduce_nblkptr(drro->drr_bonustype,
1566                     drro->drr_bonuslen);
1567
1568                 if (drro->drr_blksz != doi.doi_data_block_size ||
1569                     nblkptr < doi.doi_nblkptr) {
1570                         err = dmu_free_long_range(ra->os, drro->drr_object,
1571                             0, DMU_OBJECT_END);
1572                         if (err != 0)
1573                                 return (SET_ERROR(EINVAL));
1574                 }
1575         }
1576
1577         tx = dmu_tx_create(ra->os);
1578         dmu_tx_hold_bonus(tx, object);
1579         err = dmu_tx_assign(tx, TXG_WAIT);
1580         if (err != 0) {
1581                 dmu_tx_abort(tx);
1582                 return (err);
1583         }
1584
1585         if (object == DMU_NEW_OBJECT) {
1586                 /* currently free, want to be allocated */
1587                 err = dmu_object_claim(ra->os, drro->drr_object,
1588                     drro->drr_type, drro->drr_blksz,
1589                     drro->drr_bonustype, drro->drr_bonuslen, tx);
1590         } else if (drro->drr_type != doi.doi_type ||
1591             drro->drr_blksz != doi.doi_data_block_size ||
1592             drro->drr_bonustype != doi.doi_bonus_type ||
1593             drro->drr_bonuslen != doi.doi_bonus_size) {
1594                 /* currently allocated, but with different properties */
1595                 err = dmu_object_reclaim(ra->os, drro->drr_object,
1596                     drro->drr_type, drro->drr_blksz,
1597                     drro->drr_bonustype, drro->drr_bonuslen, tx);
1598         }
1599         if (err != 0) {
1600                 dmu_tx_commit(tx);
1601                 return (SET_ERROR(EINVAL));
1602         }
1603
1604         dmu_object_set_checksum(ra->os, drro->drr_object,
1605             drro->drr_checksumtype, tx);
1606         dmu_object_set_compress(ra->os, drro->drr_object,
1607             drro->drr_compress, tx);
1608
1609         if (data != NULL) {
1610                 dmu_buf_t *db;
1611
1612                 VERIFY0(dmu_bonus_hold(ra->os, drro->drr_object, FTAG, &db));
1613                 dmu_buf_will_dirty(db, tx);
1614
1615                 ASSERT3U(db->db_size, >=, drro->drr_bonuslen);
1616                 bcopy(data, db->db_data, drro->drr_bonuslen);
1617                 if (ra->byteswap) {
1618                         dmu_object_byteswap_t byteswap =
1619                             DMU_OT_BYTESWAP(drro->drr_bonustype);
1620                         dmu_ot_byteswap[byteswap].ob_func(db->db_data,
1621                             drro->drr_bonuslen);
1622                 }
1623                 dmu_buf_rele(db, FTAG);
1624         }
1625         dmu_tx_commit(tx);
1626         return (0);
1627 }
1628
1629 /* ARGSUSED */
1630 static int
1631 restore_freeobjects(struct restorearg *ra,
1632     struct drr_freeobjects *drrfo)
1633 {
1634         uint64_t obj;
1635
1636         if (drrfo->drr_firstobj + drrfo->drr_numobjs < drrfo->drr_firstobj)
1637                 return (SET_ERROR(EINVAL));
1638
1639         for (obj = drrfo->drr_firstobj;
1640             obj < drrfo->drr_firstobj + drrfo->drr_numobjs;
1641             (void) dmu_object_next(ra->os, &obj, FALSE, 0)) {
1642                 int err;
1643
1644                 if (dmu_object_info(ra->os, obj, NULL) != 0)
1645                         continue;
1646
1647                 err = dmu_free_long_object(ra->os, obj);
1648                 if (err != 0)
1649                         return (err);
1650         }
1651         return (0);
1652 }
1653
1654 static int
1655 restore_write(struct restorearg *ra, struct drr_write *drrw, arc_buf_t *abuf)
1656 {
1657         dmu_tx_t *tx;
1658         int err;
1659
1660         if (drrw->drr_offset + drrw->drr_length < drrw->drr_offset ||
1661             !DMU_OT_IS_VALID(drrw->drr_type))
1662                 return (SET_ERROR(EINVAL));
1663
1664         if (dmu_object_info(ra->os, drrw->drr_object, NULL) != 0)
1665                 return (SET_ERROR(EINVAL));
1666
1667         tx = dmu_tx_create(ra->os);
1668
1669         dmu_tx_hold_write(tx, drrw->drr_object,
1670             drrw->drr_offset, drrw->drr_length);
1671         err = dmu_tx_assign(tx, TXG_WAIT);
1672         if (err != 0) {
1673                 dmu_tx_abort(tx);
1674                 return (err);
1675         }
1676         if (ra->byteswap) {
1677                 dmu_object_byteswap_t byteswap =
1678                     DMU_OT_BYTESWAP(drrw->drr_type);
1679                 dmu_ot_byteswap[byteswap].ob_func(abuf->b_data,
1680                     drrw->drr_length);
1681         }
1682
1683         dmu_buf_t *bonus;
1684         if (dmu_bonus_hold(ra->os, drrw->drr_object, FTAG, &bonus) != 0)
1685                 return (SET_ERROR(EINVAL));
1686         dmu_assign_arcbuf(bonus, drrw->drr_offset, abuf, tx);
1687         dmu_tx_commit(tx);
1688         dmu_buf_rele(bonus, FTAG);
1689         return (0);
1690 }
1691
1692 /*
1693  * Handle a DRR_WRITE_BYREF record.  This record is used in dedup'ed
1694  * streams to refer to a copy of the data that is already on the
1695  * system because it came in earlier in the stream.  This function
1696  * finds the earlier copy of the data, and uses that copy instead of
1697  * data from the stream to fulfill this write.
1698  */
1699 static int
1700 restore_write_byref(struct restorearg *ra, struct drr_write_byref *drrwbr)
1701 {
1702         dmu_tx_t *tx;
1703         int err;
1704         guid_map_entry_t gmesrch;
1705         guid_map_entry_t *gmep;
1706         avl_index_t where;
1707         objset_t *ref_os = NULL;
1708         dmu_buf_t *dbp;
1709
1710         if (drrwbr->drr_offset + drrwbr->drr_length < drrwbr->drr_offset)
1711                 return (SET_ERROR(EINVAL));
1712
1713         /*
1714          * If the GUID of the referenced dataset is different from the
1715          * GUID of the target dataset, find the referenced dataset.
1716          */
1717         if (drrwbr->drr_toguid != drrwbr->drr_refguid) {
1718                 gmesrch.guid = drrwbr->drr_refguid;
1719                 if ((gmep = avl_find(ra->guid_to_ds_map, &gmesrch,
1720                     &where)) == NULL) {
1721                         return (SET_ERROR(EINVAL));
1722                 }
1723                 if (dmu_objset_from_ds(gmep->gme_ds, &ref_os))
1724                         return (SET_ERROR(EINVAL));
1725         } else {
1726                 ref_os = ra->os;
1727         }
1728
1729         err = dmu_buf_hold(ref_os, drrwbr->drr_refobject,
1730             drrwbr->drr_refoffset, FTAG, &dbp, DMU_READ_PREFETCH);
1731         if (err != 0)
1732                 return (err);
1733
1734         tx = dmu_tx_create(ra->os);
1735
1736         dmu_tx_hold_write(tx, drrwbr->drr_object,
1737             drrwbr->drr_offset, drrwbr->drr_length);
1738         err = dmu_tx_assign(tx, TXG_WAIT);
1739         if (err != 0) {
1740                 dmu_tx_abort(tx);
1741                 return (err);
1742         }
1743         dmu_write(ra->os, drrwbr->drr_object,
1744             drrwbr->drr_offset, drrwbr->drr_length, dbp->db_data, tx);
1745         dmu_buf_rele(dbp, FTAG);
1746         dmu_tx_commit(tx);
1747         return (0);
1748 }
1749
1750 static int
1751 restore_write_embedded(struct restorearg *ra,
1752     struct drr_write_embedded *drrwnp, void *data)
1753 {
1754         dmu_tx_t *tx;
1755         int err;
1756
1757         if (drrwnp->drr_offset + drrwnp->drr_length < drrwnp->drr_offset)
1758                 return (EINVAL);
1759
1760         if (drrwnp->drr_psize > BPE_PAYLOAD_SIZE)
1761                 return (EINVAL);
1762
1763         if (drrwnp->drr_etype >= NUM_BP_EMBEDDED_TYPES)
1764                 return (EINVAL);
1765         if (drrwnp->drr_compression >= ZIO_COMPRESS_FUNCTIONS)
1766                 return (EINVAL);
1767
1768         tx = dmu_tx_create(ra->os);
1769
1770         dmu_tx_hold_write(tx, drrwnp->drr_object,
1771             drrwnp->drr_offset, drrwnp->drr_length);
1772         err = dmu_tx_assign(tx, TXG_WAIT);
1773         if (err != 0) {
1774                 dmu_tx_abort(tx);
1775                 return (err);
1776         }
1777
1778         dmu_write_embedded(ra->os, drrwnp->drr_object,
1779             drrwnp->drr_offset, data, drrwnp->drr_etype,
1780             drrwnp->drr_compression, drrwnp->drr_lsize, drrwnp->drr_psize,
1781             ra->byteswap ^ ZFS_HOST_BYTEORDER, tx);
1782
1783         dmu_tx_commit(tx);
1784         return (0);
1785 }
1786
1787 static int
1788 restore_spill(struct restorearg *ra, struct drr_spill *drrs, void *data)
1789 {
1790         dmu_tx_t *tx;
1791         dmu_buf_t *db, *db_spill;
1792         int err;
1793
1794         if (drrs->drr_length < SPA_MINBLOCKSIZE ||
1795             drrs->drr_length > spa_maxblocksize(dmu_objset_spa(ra->os)))
1796                 return (SET_ERROR(EINVAL));
1797
1798         if (dmu_object_info(ra->os, drrs->drr_object, NULL) != 0)
1799                 return (SET_ERROR(EINVAL));
1800
1801         VERIFY0(dmu_bonus_hold(ra->os, drrs->drr_object, FTAG, &db));
1802         if ((err = dmu_spill_hold_by_bonus(db, FTAG, &db_spill)) != 0) {
1803                 dmu_buf_rele(db, FTAG);
1804                 return (err);
1805         }
1806
1807         tx = dmu_tx_create(ra->os);
1808
1809         dmu_tx_hold_spill(tx, db->db_object);
1810
1811         err = dmu_tx_assign(tx, TXG_WAIT);
1812         if (err != 0) {
1813                 dmu_buf_rele(db, FTAG);
1814                 dmu_buf_rele(db_spill, FTAG);
1815                 dmu_tx_abort(tx);
1816                 return (err);
1817         }
1818         dmu_buf_will_dirty(db_spill, tx);
1819
1820         if (db_spill->db_size < drrs->drr_length)
1821                 VERIFY(0 == dbuf_spill_set_blksz(db_spill,
1822                     drrs->drr_length, tx));
1823         bcopy(data, db_spill->db_data, drrs->drr_length);
1824
1825         dmu_buf_rele(db, FTAG);
1826         dmu_buf_rele(db_spill, FTAG);
1827
1828         dmu_tx_commit(tx);
1829         return (0);
1830 }
1831
1832 /* ARGSUSED */
1833 static int
1834 restore_free(struct restorearg *ra, struct drr_free *drrf)
1835 {
1836         int err;
1837
1838         if (drrf->drr_length != -1ULL &&
1839             drrf->drr_offset + drrf->drr_length < drrf->drr_offset)
1840                 return (SET_ERROR(EINVAL));
1841
1842         if (dmu_object_info(ra->os, drrf->drr_object, NULL) != 0)
1843                 return (SET_ERROR(EINVAL));
1844
1845         err = dmu_free_long_range(ra->os, drrf->drr_object,
1846             drrf->drr_offset, drrf->drr_length);
1847         return (err);
1848 }
1849
1850 /* used to destroy the drc_ds on error */
1851 static void
1852 dmu_recv_cleanup_ds(dmu_recv_cookie_t *drc)
1853 {
1854         char name[MAXNAMELEN];
1855         dsl_dataset_name(drc->drc_ds, name);
1856         dsl_dataset_disown(drc->drc_ds, dmu_recv_tag);
1857         (void) dsl_destroy_head(name);
1858 }
1859
1860 static void
1861 restore_cksum(struct restorearg *ra, int len, void *buf)
1862 {
1863         if (ra->byteswap) {
1864                 fletcher_4_incremental_byteswap(buf, len, &ra->cksum);
1865         } else {
1866                 fletcher_4_incremental_native(buf, len, &ra->cksum);
1867         }
1868 }
1869
1870 /*
1871  * If len != 0, read payload into buf.
1872  * Read next record's header into ra->next_drr.
1873  * Verify checksum of payload and next record.
1874  */
1875 static int
1876 restore_read_payload_and_next_header(struct restorearg *ra, int len, void *buf)
1877 {
1878         int err;
1879
1880         if (len != 0) {
1881                 ASSERT3U(len, <=, ra->bufsize);
1882                 err = restore_read(ra, len, buf);
1883                 if (err != 0)
1884                         return (err);
1885                 restore_cksum(ra, len, buf);
1886         }
1887
1888         ra->prev_cksum = ra->cksum;
1889
1890         err = restore_read(ra, sizeof (*ra->next_drr), ra->next_drr);
1891         if (err != 0)
1892                 return (err);
1893         if (ra->next_drr->drr_type == DRR_BEGIN)
1894                 return (SET_ERROR(EINVAL));
1895
1896         /*
1897          * Note: checksum is of everything up to but not including the
1898          * checksum itself.
1899          */
1900         ASSERT3U(offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
1901             ==, sizeof (dmu_replay_record_t) - sizeof (zio_cksum_t));
1902         restore_cksum(ra,
1903             offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
1904             ra->next_drr);
1905
1906         zio_cksum_t cksum_orig = ra->next_drr->drr_u.drr_checksum.drr_checksum;
1907         zio_cksum_t *cksump = &ra->next_drr->drr_u.drr_checksum.drr_checksum;
1908
1909         if (ra->byteswap)
1910                 byteswap_record(ra->next_drr);
1911
1912         if ((!ZIO_CHECKSUM_IS_ZERO(cksump)) &&
1913             !ZIO_CHECKSUM_EQUAL(ra->cksum, *cksump))
1914                 return (SET_ERROR(ECKSUM));
1915
1916         restore_cksum(ra, sizeof (cksum_orig), &cksum_orig);
1917
1918         return (0);
1919 }
1920
1921 static int
1922 restore_process_record(struct restorearg *ra)
1923 {
1924         int err;
1925
1926         switch (ra->drr->drr_type) {
1927         case DRR_OBJECT:
1928         {
1929                 struct drr_object *drro = &ra->drr->drr_u.drr_object;
1930                 err = restore_read_payload_and_next_header(ra,
1931                     P2ROUNDUP(drro->drr_bonuslen, 8), ra->buf);
1932                 if (err != 0)
1933                         return (err);
1934                 return (restore_object(ra, drro, ra->buf));
1935         }
1936         case DRR_FREEOBJECTS:
1937         {
1938                 struct drr_freeobjects *drrfo =
1939                     &ra->drr->drr_u.drr_freeobjects;
1940                 err = restore_read_payload_and_next_header(ra, 0, NULL);
1941                 if (err != 0)
1942                         return (err);
1943                 return (restore_freeobjects(ra, drrfo));
1944         }
1945         case DRR_WRITE:
1946         {
1947                 struct drr_write *drrw = &ra->drr->drr_u.drr_write;
1948                 arc_buf_t *abuf = arc_loan_buf(dmu_objset_spa(ra->os),
1949                     drrw->drr_length);
1950
1951                 err = restore_read_payload_and_next_header(ra,
1952                     drrw->drr_length, abuf->b_data);
1953                 if (err != 0)
1954                         return (err);
1955                 err = restore_write(ra, drrw, abuf);
1956                 /* if restore_write() is successful, it consumes the arc_buf */
1957                 if (err != 0)
1958                         dmu_return_arcbuf(abuf);
1959                 return (err);
1960         }
1961         case DRR_WRITE_BYREF:
1962         {
1963                 struct drr_write_byref *drrwbr =
1964                     &ra->drr->drr_u.drr_write_byref;
1965                 err = restore_read_payload_and_next_header(ra, 0, NULL);
1966                 if (err != 0)
1967                         return (err);
1968                 return (restore_write_byref(ra, drrwbr));
1969         }
1970         case DRR_WRITE_EMBEDDED:
1971         {
1972                 struct drr_write_embedded *drrwe =
1973                     &ra->drr->drr_u.drr_write_embedded;
1974                 err = restore_read_payload_and_next_header(ra,
1975                     P2ROUNDUP(drrwe->drr_psize, 8), ra->buf);
1976                 if (err != 0)
1977                         return (err);
1978                 return (restore_write_embedded(ra, drrwe, ra->buf));
1979         }
1980         case DRR_FREE:
1981         {
1982                 struct drr_free *drrf = &ra->drr->drr_u.drr_free;
1983                 err = restore_read_payload_and_next_header(ra, 0, NULL);
1984                 if (err != 0)
1985                         return (err);
1986                 return (restore_free(ra, drrf));
1987         }
1988         case DRR_END:
1989         {
1990                 struct drr_end *drre = &ra->drr->drr_u.drr_end;
1991                 if (!ZIO_CHECKSUM_EQUAL(ra->prev_cksum, drre->drr_checksum))
1992                         return (SET_ERROR(EINVAL));
1993                 return (0);
1994         }
1995         case DRR_SPILL:
1996         {
1997                 struct drr_spill *drrs = &ra->drr->drr_u.drr_spill;
1998                 err = restore_read_payload_and_next_header(ra,
1999                     drrs->drr_length, ra->buf);
2000                 if (err != 0)
2001                         return (err);
2002                 return (restore_spill(ra, drrs, ra->buf));
2003         }
2004         default:
2005                 return (SET_ERROR(EINVAL));
2006         }
2007 }
2008
2009 /*
2010  * NB: callers *must* call dmu_recv_end() if this succeeds.
2011  */
2012 int
2013 dmu_recv_stream(dmu_recv_cookie_t *drc, struct file *fp, offset_t *voffp,
2014     int cleanup_fd, uint64_t *action_handlep)
2015 {
2016         int err = 0;
2017         struct restorearg ra = { 0 };
2018         int featureflags;
2019
2020         ra.byteswap = drc->drc_byteswap;
2021         ra.cksum = drc->drc_cksum;
2022         ra.td = curthread;
2023         ra.fp = fp;
2024         ra.voff = *voffp;
2025         ra.bufsize = SPA_MAXBLOCKSIZE;
2026         ra.drr = kmem_alloc(sizeof (*ra.drr), KM_SLEEP);
2027         ra.buf = kmem_alloc(ra.bufsize, KM_SLEEP);
2028         ra.next_drr = kmem_alloc(sizeof (*ra.next_drr), KM_SLEEP);
2029
2030         /* these were verified in dmu_recv_begin */
2031         ASSERT3U(DMU_GET_STREAM_HDRTYPE(drc->drc_drrb->drr_versioninfo), ==,
2032             DMU_SUBSTREAM);
2033         ASSERT3U(drc->drc_drrb->drr_type, <, DMU_OST_NUMTYPES);
2034
2035         /*
2036          * Open the objset we are modifying.
2037          */
2038         VERIFY0(dmu_objset_from_ds(drc->drc_ds, &ra.os));
2039
2040         ASSERT(dsl_dataset_phys(drc->drc_ds)->ds_flags & DS_FLAG_INCONSISTENT);
2041
2042         featureflags = DMU_GET_FEATUREFLAGS(drc->drc_drrb->drr_versioninfo);
2043
2044         /* if this stream is dedup'ed, set up the avl tree for guid mapping */
2045         if (featureflags & DMU_BACKUP_FEATURE_DEDUP) {
2046                 minor_t minor;
2047
2048                 if (cleanup_fd == -1) {
2049                         ra.err = SET_ERROR(EBADF);
2050                         goto out;
2051                 }
2052                 ra.err = zfs_onexit_fd_hold(cleanup_fd, &minor);
2053                 if (ra.err != 0) {
2054                         cleanup_fd = -1;
2055                         goto out;
2056                 }
2057
2058                 if (*action_handlep == 0) {
2059                         ra.guid_to_ds_map =
2060                             kmem_alloc(sizeof (avl_tree_t), KM_SLEEP);
2061                         avl_create(ra.guid_to_ds_map, guid_compare,
2062                             sizeof (guid_map_entry_t),
2063                             offsetof(guid_map_entry_t, avlnode));
2064                         err = zfs_onexit_add_cb(minor,
2065                             free_guid_map_onexit, ra.guid_to_ds_map,
2066                             action_handlep);
2067                         if (ra.err != 0)
2068                                 goto out;
2069                 } else {
2070                         err = zfs_onexit_cb_data(minor, *action_handlep,
2071                             (void **)&ra.guid_to_ds_map);
2072                         if (ra.err != 0)
2073                                 goto out;
2074                 }
2075
2076                 drc->drc_guid_to_ds_map = ra.guid_to_ds_map;
2077         }
2078
2079         err = restore_read_payload_and_next_header(&ra, 0, NULL);
2080         if (err != 0)
2081                 goto out;
2082         for (;;) {
2083                 void *tmp;
2084
2085                 if (issig(JUSTLOOKING) && issig(FORREAL)) {
2086                         err = SET_ERROR(EINTR);
2087                         break;
2088                 }
2089
2090                 tmp = ra.next_drr;
2091                 ra.next_drr = ra.drr;
2092                 ra.drr = tmp;
2093
2094                 /* process ra.drr, read in ra.next_drr */
2095                 err = restore_process_record(&ra);
2096                 if (err != 0)
2097                         break;
2098                 if (ra.drr->drr_type == DRR_END)
2099                         break;
2100         }
2101
2102 out:
2103         if ((featureflags & DMU_BACKUP_FEATURE_DEDUP) && (cleanup_fd != -1))
2104                 zfs_onexit_fd_rele(cleanup_fd);
2105
2106         if (err != 0) {
2107                 /*
2108                  * destroy what we created, so we don't leave it in the
2109                  * inconsistent restoring state.
2110                  */
2111                 dmu_recv_cleanup_ds(drc);
2112         }
2113
2114         kmem_free(ra.drr, sizeof (*ra.drr));
2115         kmem_free(ra.buf, ra.bufsize);
2116         kmem_free(ra.next_drr, sizeof (*ra.next_drr));
2117         *voffp = ra.voff;
2118         return (err);
2119 }
2120
2121 static int
2122 dmu_recv_end_check(void *arg, dmu_tx_t *tx)
2123 {
2124         dmu_recv_cookie_t *drc = arg;
2125         dsl_pool_t *dp = dmu_tx_pool(tx);
2126         int error;
2127
2128         ASSERT3P(drc->drc_ds->ds_owner, ==, dmu_recv_tag);
2129
2130         if (!drc->drc_newfs) {
2131                 dsl_dataset_t *origin_head;
2132
2133                 error = dsl_dataset_hold(dp, drc->drc_tofs, FTAG, &origin_head);
2134                 if (error != 0)
2135                         return (error);
2136                 if (drc->drc_force) {
2137                         /*
2138                          * We will destroy any snapshots in tofs (i.e. before
2139                          * origin_head) that are after the origin (which is
2140                          * the snap before drc_ds, because drc_ds can not
2141                          * have any snaps of its own).
2142                          */
2143                         uint64_t obj;
2144
2145                         obj = dsl_dataset_phys(origin_head)->ds_prev_snap_obj;
2146                         while (obj !=
2147                             dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj) {
2148                                 dsl_dataset_t *snap;
2149                                 error = dsl_dataset_hold_obj(dp, obj, FTAG,
2150                                     &snap);
2151                                 if (error != 0)
2152                                         break;
2153                                 if (snap->ds_dir != origin_head->ds_dir)
2154                                         error = SET_ERROR(EINVAL);
2155                                 if (error == 0)  {
2156                                         error = dsl_destroy_snapshot_check_impl(
2157                                             snap, B_FALSE);
2158                                 }
2159                                 obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
2160                                 dsl_dataset_rele(snap, FTAG);
2161                                 if (error != 0)
2162                                         break;
2163                         }
2164                         if (error != 0) {
2165                                 dsl_dataset_rele(origin_head, FTAG);
2166                                 return (error);
2167                         }
2168                 }
2169                 error = dsl_dataset_clone_swap_check_impl(drc->drc_ds,
2170                     origin_head, drc->drc_force, drc->drc_owner, tx);
2171                 if (error != 0) {
2172                         dsl_dataset_rele(origin_head, FTAG);
2173                         return (error);
2174                 }
2175                 error = dsl_dataset_snapshot_check_impl(origin_head,
2176                     drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
2177                 dsl_dataset_rele(origin_head, FTAG);
2178                 if (error != 0)
2179                         return (error);
2180
2181                 error = dsl_destroy_head_check_impl(drc->drc_ds, 1);
2182         } else {
2183                 error = dsl_dataset_snapshot_check_impl(drc->drc_ds,
2184                     drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
2185         }
2186         return (error);
2187 }
2188
2189 static void
2190 dmu_recv_end_sync(void *arg, dmu_tx_t *tx)
2191 {
2192         dmu_recv_cookie_t *drc = arg;
2193         dsl_pool_t *dp = dmu_tx_pool(tx);
2194
2195         spa_history_log_internal_ds(drc->drc_ds, "finish receiving",
2196             tx, "snap=%s", drc->drc_tosnap);
2197
2198         if (!drc->drc_newfs) {
2199                 dsl_dataset_t *origin_head;
2200
2201                 VERIFY0(dsl_dataset_hold(dp, drc->drc_tofs, FTAG,
2202                     &origin_head));
2203
2204                 if (drc->drc_force) {
2205                         /*
2206                          * Destroy any snapshots of drc_tofs (origin_head)
2207                          * after the origin (the snap before drc_ds).
2208                          */
2209                         uint64_t obj;
2210
2211                         obj = dsl_dataset_phys(origin_head)->ds_prev_snap_obj;
2212                         while (obj !=
2213                             dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj) {
2214                                 dsl_dataset_t *snap;
2215                                 VERIFY0(dsl_dataset_hold_obj(dp, obj, FTAG,
2216                                     &snap));
2217                                 ASSERT3P(snap->ds_dir, ==, origin_head->ds_dir);
2218                                 obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
2219                                 dsl_destroy_snapshot_sync_impl(snap,
2220                                     B_FALSE, tx);
2221                                 dsl_dataset_rele(snap, FTAG);
2222                         }
2223                 }
2224                 VERIFY3P(drc->drc_ds->ds_prev, ==,
2225                     origin_head->ds_prev);
2226
2227                 dsl_dataset_clone_swap_sync_impl(drc->drc_ds,
2228                     origin_head, tx);
2229                 dsl_dataset_snapshot_sync_impl(origin_head,
2230                     drc->drc_tosnap, tx);
2231
2232                 /* set snapshot's creation time and guid */
2233                 dmu_buf_will_dirty(origin_head->ds_prev->ds_dbuf, tx);
2234                 dsl_dataset_phys(origin_head->ds_prev)->ds_creation_time =
2235                     drc->drc_drrb->drr_creation_time;
2236                 dsl_dataset_phys(origin_head->ds_prev)->ds_guid =
2237                     drc->drc_drrb->drr_toguid;
2238                 dsl_dataset_phys(origin_head->ds_prev)->ds_flags &=
2239                     ~DS_FLAG_INCONSISTENT;
2240
2241                 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2242                 dsl_dataset_phys(origin_head)->ds_flags &=
2243                     ~DS_FLAG_INCONSISTENT;
2244
2245                 dsl_dataset_rele(origin_head, FTAG);
2246                 dsl_destroy_head_sync_impl(drc->drc_ds, tx);
2247
2248                 if (drc->drc_owner != NULL)
2249                         VERIFY3P(origin_head->ds_owner, ==, drc->drc_owner);
2250         } else {
2251                 dsl_dataset_t *ds = drc->drc_ds;
2252
2253                 dsl_dataset_snapshot_sync_impl(ds, drc->drc_tosnap, tx);
2254
2255                 /* set snapshot's creation time and guid */
2256                 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
2257                 dsl_dataset_phys(ds->ds_prev)->ds_creation_time =
2258                     drc->drc_drrb->drr_creation_time;
2259                 dsl_dataset_phys(ds->ds_prev)->ds_guid =
2260                     drc->drc_drrb->drr_toguid;
2261                 dsl_dataset_phys(ds->ds_prev)->ds_flags &=
2262                     ~DS_FLAG_INCONSISTENT;
2263
2264                 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2265                 dsl_dataset_phys(ds)->ds_flags &= ~DS_FLAG_INCONSISTENT;
2266         }
2267         drc->drc_newsnapobj = dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj;
2268         /*
2269          * Release the hold from dmu_recv_begin.  This must be done before
2270          * we return to open context, so that when we free the dataset's dnode,
2271          * we can evict its bonus buffer.
2272          */
2273         dsl_dataset_disown(drc->drc_ds, dmu_recv_tag);
2274         drc->drc_ds = NULL;
2275 }
2276
2277 static int
2278 add_ds_to_guidmap(const char *name, avl_tree_t *guid_map, uint64_t snapobj)
2279 {
2280         dsl_pool_t *dp;
2281         dsl_dataset_t *snapds;
2282         guid_map_entry_t *gmep;
2283         int err;
2284
2285         ASSERT(guid_map != NULL);
2286
2287         err = dsl_pool_hold(name, FTAG, &dp);
2288         if (err != 0)
2289                 return (err);
2290         gmep = kmem_alloc(sizeof (*gmep), KM_SLEEP);
2291         err = dsl_dataset_hold_obj(dp, snapobj, gmep, &snapds);
2292         if (err == 0) {
2293                 gmep->guid = dsl_dataset_phys(snapds)->ds_guid;
2294                 gmep->gme_ds = snapds;
2295                 avl_add(guid_map, gmep);
2296                 dsl_dataset_long_hold(snapds, gmep);
2297         } else
2298                 kmem_free(gmep, sizeof (*gmep));
2299
2300         dsl_pool_rele(dp, FTAG);
2301         return (err);
2302 }
2303
2304 static int dmu_recv_end_modified_blocks = 3;
2305
2306 static int
2307 dmu_recv_existing_end(dmu_recv_cookie_t *drc)
2308 {
2309         int error;
2310         char name[MAXNAMELEN];
2311
2312 #ifdef _KERNEL
2313         /*
2314          * We will be destroying the ds; make sure its origin is unmounted if
2315          * necessary.
2316          */
2317         dsl_dataset_name(drc->drc_ds, name);
2318         zfs_destroy_unmount_origin(name);
2319 #endif
2320
2321         error = dsl_sync_task(drc->drc_tofs,
2322             dmu_recv_end_check, dmu_recv_end_sync, drc,
2323             dmu_recv_end_modified_blocks, ZFS_SPACE_CHECK_NORMAL);
2324
2325         if (error != 0)
2326                 dmu_recv_cleanup_ds(drc);
2327         return (error);
2328 }
2329
2330 static int
2331 dmu_recv_new_end(dmu_recv_cookie_t *drc)
2332 {
2333         int error;
2334
2335         error = dsl_sync_task(drc->drc_tofs,
2336             dmu_recv_end_check, dmu_recv_end_sync, drc,
2337             dmu_recv_end_modified_blocks, ZFS_SPACE_CHECK_NORMAL);
2338
2339         if (error != 0) {
2340                 dmu_recv_cleanup_ds(drc);
2341         } else if (drc->drc_guid_to_ds_map != NULL) {
2342                 (void) add_ds_to_guidmap(drc->drc_tofs,
2343                     drc->drc_guid_to_ds_map,
2344                     drc->drc_newsnapobj);
2345         }
2346         return (error);
2347 }
2348
2349 int
2350 dmu_recv_end(dmu_recv_cookie_t *drc, void *owner)
2351 {
2352         drc->drc_owner = owner;
2353
2354         if (drc->drc_newfs)
2355                 return (dmu_recv_new_end(drc));
2356         else
2357                 return (dmu_recv_existing_end(drc));
2358 }
2359
2360 /*
2361  * Return TRUE if this objset is currently being received into.
2362  */
2363 boolean_t
2364 dmu_objset_is_receiving(objset_t *os)
2365 {
2366         return (os->os_dsl_dataset != NULL &&
2367             os->os_dsl_dataset->ds_owner == dmu_recv_tag);
2368 }