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) 2013 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  */
28 
29 #include <sys/dmu.h>
30 #include <sys/dmu_impl.h>
31 #include <sys/dmu_tx.h>
32 #include <sys/dbuf.h>
33 #include <sys/dnode.h>
34 #include <sys/zfs_context.h>
35 #include <sys/dmu_objset.h>
36 #include <sys/dmu_traverse.h>
37 #include <sys/dsl_dataset.h>
38 #include <sys/dsl_dir.h>
39 #include <sys/dsl_prop.h>
40 #include <sys/dsl_pool.h>
41 #include <sys/dsl_synctask.h>
42 #include <sys/zfs_ioctl.h>
43 #include <sys/zap.h>
44 #include <sys/zio_checksum.h>
45 #include <sys/zfs_znode.h>
46 #include <zfs_fletcher.h>
47 #include <sys/avl.h>
48 #include <sys/ddt.h>
49 #include <sys/zfs_onexit.h>
50 #include <sys/dmu_send.h>
51 #include <sys/dsl_destroy.h>
52 #include <sys/dsl_bookmark.h>
53 
54 /* Set this tunable to TRUE to replace corrupt data with 0x2f5baddb10c */
55 int zfs_send_corrupt_data = B_FALSE;
56 
57 static char *dmu_recv_tag = "dmu_recv_tag";
58 static const char *recv_clone_name = "%recv";
59 
60 static int
dump_bytes(dmu_sendarg_t * dsp,void * buf,int len)61 dump_bytes(dmu_sendarg_t *dsp, void *buf, int len)
62 {
63 	dsl_dataset_t *ds = dsp->dsa_os->os_dsl_dataset;
64 	struct uio auio;
65 	struct iovec aiov;
66 	ASSERT0(len % 8);
67 
68 	fletcher_4_incremental_native(buf, len, &dsp->dsa_zc);
69 	aiov.iov_base = buf;
70 	aiov.iov_len = len;
71 	auio.uio_iov = &aiov;
72 	auio.uio_iovcnt = 1;
73 	auio.uio_resid = len;
74 	auio.uio_segflg = UIO_SYSSPACE;
75 	auio.uio_rw = UIO_WRITE;
76 	auio.uio_offset = (off_t)-1;
77 	auio.uio_td = dsp->dsa_td;
78 #ifdef _KERNEL
79 	if (dsp->dsa_fp->f_type == DTYPE_VNODE)
80 		bwillwrite();
81 	dsp->dsa_err = fo_write(dsp->dsa_fp, &auio, dsp->dsa_td->td_ucred, 0,
82 	    dsp->dsa_td);
83 #else
84 	fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__);
85 	dsp->dsa_err = EOPNOTSUPP;
86 #endif
87 	mutex_enter(&ds->ds_sendstream_lock);
88 	*dsp->dsa_off += len;
89 	mutex_exit(&ds->ds_sendstream_lock);
90 
91 	return (dsp->dsa_err);
92 }
93 
94 static int
dump_free(dmu_sendarg_t * dsp,uint64_t object,uint64_t offset,uint64_t length)95 dump_free(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
96     uint64_t length)
97 {
98 	struct drr_free *drrf = &(dsp->dsa_drr->drr_u.drr_free);
99 
100 	/*
101 	 * When we receive a free record, dbuf_free_range() assumes
102 	 * that the receiving system doesn't have any dbufs in the range
103 	 * being freed.  This is always true because there is a one-record
104 	 * constraint: we only send one WRITE record for any given
105 	 * object+offset.  We know that the one-record constraint is
106 	 * true because we always send data in increasing order by
107 	 * object,offset.
108 	 *
109 	 * If the increasing-order constraint ever changes, we should find
110 	 * another way to assert that the one-record constraint is still
111 	 * satisfied.
112 	 */
113 	ASSERT(object > dsp->dsa_last_data_object ||
114 	    (object == dsp->dsa_last_data_object &&
115 	    offset > dsp->dsa_last_data_offset));
116 
117 	/*
118 	 * If we are doing a non-incremental send, then there can't
119 	 * be any data in the dataset we're receiving into.  Therefore
120 	 * a free record would simply be a no-op.  Save space by not
121 	 * sending it to begin with.
122 	 */
123 	if (!dsp->dsa_incremental)
124 		return (0);
125 
126 	if (length != -1ULL && offset + length < offset)
127 		length = -1ULL;
128 
129 	/*
130 	 * If there is a pending op, but it's not PENDING_FREE, push it out,
131 	 * since free block aggregation can only be done for blocks of the
132 	 * same type (i.e., DRR_FREE records can only be aggregated with
133 	 * other DRR_FREE records.  DRR_FREEOBJECTS records can only be
134 	 * aggregated with other DRR_FREEOBJECTS records.
135 	 */
136 	if (dsp->dsa_pending_op != PENDING_NONE &&
137 	    dsp->dsa_pending_op != PENDING_FREE) {
138 		if (dump_bytes(dsp, dsp->dsa_drr,
139 		    sizeof (dmu_replay_record_t)) != 0)
140 			return (SET_ERROR(EINTR));
141 		dsp->dsa_pending_op = PENDING_NONE;
142 	}
143 
144 	if (dsp->dsa_pending_op == PENDING_FREE) {
145 		/*
146 		 * There should never be a PENDING_FREE if length is -1
147 		 * (because dump_dnode is the only place where this
148 		 * function is called with a -1, and only after flushing
149 		 * any pending record).
150 		 */
151 		ASSERT(length != -1ULL);
152 		/*
153 		 * Check to see whether this free block can be aggregated
154 		 * with pending one.
155 		 */
156 		if (drrf->drr_object == object && drrf->drr_offset +
157 		    drrf->drr_length == offset) {
158 			drrf->drr_length += length;
159 			return (0);
160 		} else {
161 			/* not a continuation.  Push out pending record */
162 			if (dump_bytes(dsp, dsp->dsa_drr,
163 			    sizeof (dmu_replay_record_t)) != 0)
164 				return (SET_ERROR(EINTR));
165 			dsp->dsa_pending_op = PENDING_NONE;
166 		}
167 	}
168 	/* create a FREE record and make it pending */
169 	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
170 	dsp->dsa_drr->drr_type = DRR_FREE;
171 	drrf->drr_object = object;
172 	drrf->drr_offset = offset;
173 	drrf->drr_length = length;
174 	drrf->drr_toguid = dsp->dsa_toguid;
175 	if (length == -1ULL) {
176 		if (dump_bytes(dsp, dsp->dsa_drr,
177 		    sizeof (dmu_replay_record_t)) != 0)
178 			return (SET_ERROR(EINTR));
179 	} else {
180 		dsp->dsa_pending_op = PENDING_FREE;
181 	}
182 
183 	return (0);
184 }
185 
186 static int
dump_data(dmu_sendarg_t * dsp,dmu_object_type_t type,uint64_t object,uint64_t offset,int blksz,const blkptr_t * bp,void * data)187 dump_data(dmu_sendarg_t *dsp, dmu_object_type_t type,
188     uint64_t object, uint64_t offset, int blksz, const blkptr_t *bp, void *data)
189 {
190 	struct drr_write *drrw = &(dsp->dsa_drr->drr_u.drr_write);
191 
192 	/*
193 	 * We send data in increasing object, offset order.
194 	 * See comment in dump_free() for details.
195 	 */
196 	ASSERT(object > dsp->dsa_last_data_object ||
197 	    (object == dsp->dsa_last_data_object &&
198 	    offset > dsp->dsa_last_data_offset));
199 	dsp->dsa_last_data_object = object;
200 	dsp->dsa_last_data_offset = offset + blksz - 1;
201 
202 	/*
203 	 * If there is any kind of pending aggregation (currently either
204 	 * a grouping of free objects or free blocks), push it out to
205 	 * the stream, since aggregation can't be done across operations
206 	 * of different types.
207 	 */
208 	if (dsp->dsa_pending_op != PENDING_NONE) {
209 		if (dump_bytes(dsp, dsp->dsa_drr,
210 		    sizeof (dmu_replay_record_t)) != 0)
211 			return (SET_ERROR(EINTR));
212 		dsp->dsa_pending_op = PENDING_NONE;
213 	}
214 	/* write a DATA record */
215 	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
216 	dsp->dsa_drr->drr_type = DRR_WRITE;
217 	drrw->drr_object = object;
218 	drrw->drr_type = type;
219 	drrw->drr_offset = offset;
220 	drrw->drr_length = blksz;
221 	drrw->drr_toguid = dsp->dsa_toguid;
222 	drrw->drr_checksumtype = BP_GET_CHECKSUM(bp);
223 	if (zio_checksum_table[drrw->drr_checksumtype].ci_dedup)
224 		drrw->drr_checksumflags |= DRR_CHECKSUM_DEDUP;
225 	DDK_SET_LSIZE(&drrw->drr_key, BP_GET_LSIZE(bp));
226 	DDK_SET_PSIZE(&drrw->drr_key, BP_GET_PSIZE(bp));
227 	DDK_SET_COMPRESS(&drrw->drr_key, BP_GET_COMPRESS(bp));
228 	drrw->drr_key.ddk_cksum = bp->blk_cksum;
229 
230 	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)) != 0)
231 		return (SET_ERROR(EINTR));
232 	if (dump_bytes(dsp, data, blksz) != 0)
233 		return (SET_ERROR(EINTR));
234 	return (0);
235 }
236 
237 static int
dump_spill(dmu_sendarg_t * dsp,uint64_t object,int blksz,void * data)238 dump_spill(dmu_sendarg_t *dsp, uint64_t object, int blksz, void *data)
239 {
240 	struct drr_spill *drrs = &(dsp->dsa_drr->drr_u.drr_spill);
241 
242 	if (dsp->dsa_pending_op != PENDING_NONE) {
243 		if (dump_bytes(dsp, dsp->dsa_drr,
244 		    sizeof (dmu_replay_record_t)) != 0)
245 			return (SET_ERROR(EINTR));
246 		dsp->dsa_pending_op = PENDING_NONE;
247 	}
248 
249 	/* write a SPILL record */
250 	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
251 	dsp->dsa_drr->drr_type = DRR_SPILL;
252 	drrs->drr_object = object;
253 	drrs->drr_length = blksz;
254 	drrs->drr_toguid = dsp->dsa_toguid;
255 
256 	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)))
257 		return (SET_ERROR(EINTR));
258 	if (dump_bytes(dsp, data, blksz))
259 		return (SET_ERROR(EINTR));
260 	return (0);
261 }
262 
263 static int
dump_freeobjects(dmu_sendarg_t * dsp,uint64_t firstobj,uint64_t numobjs)264 dump_freeobjects(dmu_sendarg_t *dsp, uint64_t firstobj, uint64_t numobjs)
265 {
266 	struct drr_freeobjects *drrfo = &(dsp->dsa_drr->drr_u.drr_freeobjects);
267 
268 	/* See comment in dump_free(). */
269 	if (!dsp->dsa_incremental)
270 		return (0);
271 
272 	/*
273 	 * If there is a pending op, but it's not PENDING_FREEOBJECTS,
274 	 * push it out, since free block aggregation can only be done for
275 	 * blocks of the same type (i.e., DRR_FREE records can only be
276 	 * aggregated with other DRR_FREE records.  DRR_FREEOBJECTS records
277 	 * can only be aggregated with other DRR_FREEOBJECTS records.
278 	 */
279 	if (dsp->dsa_pending_op != PENDING_NONE &&
280 	    dsp->dsa_pending_op != PENDING_FREEOBJECTS) {
281 		if (dump_bytes(dsp, dsp->dsa_drr,
282 		    sizeof (dmu_replay_record_t)) != 0)
283 			return (SET_ERROR(EINTR));
284 		dsp->dsa_pending_op = PENDING_NONE;
285 	}
286 	if (dsp->dsa_pending_op == PENDING_FREEOBJECTS) {
287 		/*
288 		 * See whether this free object array can be aggregated
289 		 * with pending one
290 		 */
291 		if (drrfo->drr_firstobj + drrfo->drr_numobjs == firstobj) {
292 			drrfo->drr_numobjs += numobjs;
293 			return (0);
294 		} else {
295 			/* can't be aggregated.  Push out pending record */
296 			if (dump_bytes(dsp, dsp->dsa_drr,
297 			    sizeof (dmu_replay_record_t)) != 0)
298 				return (SET_ERROR(EINTR));
299 			dsp->dsa_pending_op = PENDING_NONE;
300 		}
301 	}
302 
303 	/* write a FREEOBJECTS record */
304 	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
305 	dsp->dsa_drr->drr_type = DRR_FREEOBJECTS;
306 	drrfo->drr_firstobj = firstobj;
307 	drrfo->drr_numobjs = numobjs;
308 	drrfo->drr_toguid = dsp->dsa_toguid;
309 
310 	dsp->dsa_pending_op = PENDING_FREEOBJECTS;
311 
312 	return (0);
313 }
314 
315 static int
dump_dnode(dmu_sendarg_t * dsp,uint64_t object,dnode_phys_t * dnp)316 dump_dnode(dmu_sendarg_t *dsp, uint64_t object, dnode_phys_t *dnp)
317 {
318 	struct drr_object *drro = &(dsp->dsa_drr->drr_u.drr_object);
319 
320 	if (dnp == NULL || dnp->dn_type == DMU_OT_NONE)
321 		return (dump_freeobjects(dsp, object, 1));
322 
323 	if (dsp->dsa_pending_op != PENDING_NONE) {
324 		if (dump_bytes(dsp, dsp->dsa_drr,
325 		    sizeof (dmu_replay_record_t)) != 0)
326 			return (SET_ERROR(EINTR));
327 		dsp->dsa_pending_op = PENDING_NONE;
328 	}
329 
330 	/* write an OBJECT record */
331 	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
332 	dsp->dsa_drr->drr_type = DRR_OBJECT;
333 	drro->drr_object = object;
334 	drro->drr_type = dnp->dn_type;
335 	drro->drr_bonustype = dnp->dn_bonustype;
336 	drro->drr_blksz = dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT;
337 	drro->drr_bonuslen = dnp->dn_bonuslen;
338 	drro->drr_checksumtype = dnp->dn_checksum;
339 	drro->drr_compress = dnp->dn_compress;
340 	drro->drr_toguid = dsp->dsa_toguid;
341 
342 	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)) != 0)
343 		return (SET_ERROR(EINTR));
344 
345 	if (dump_bytes(dsp, DN_BONUS(dnp), P2ROUNDUP(dnp->dn_bonuslen, 8)) != 0)
346 		return (SET_ERROR(EINTR));
347 
348 	/* Free anything past the end of the file. */
349 	if (dump_free(dsp, object, (dnp->dn_maxblkid + 1) *
350 	    (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT), -1ULL) != 0)
351 		return (SET_ERROR(EINTR));
352 	if (dsp->dsa_err != 0)
353 		return (SET_ERROR(EINTR));
354 	return (0);
355 }
356 
357 #define	BP_SPAN(dnp, level) \
358 	(((uint64_t)dnp->dn_datablkszsec) << (SPA_MINBLOCKSHIFT + \
359 	(level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT)))
360 
361 /* ARGSUSED */
362 static int
backup_cb(spa_t * spa,zilog_t * zilog,const blkptr_t * bp,const zbookmark_t * zb,const dnode_phys_t * dnp,void * arg)363 backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
364     const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
365 {
366 	dmu_sendarg_t *dsp = arg;
367 	dmu_object_type_t type = bp ? BP_GET_TYPE(bp) : DMU_OT_NONE;
368 	int err = 0;
369 
370 	if (issig(JUSTLOOKING) && issig(FORREAL))
371 		return (SET_ERROR(EINTR));
372 
373 	if (zb->zb_object != DMU_META_DNODE_OBJECT &&
374 	    DMU_OBJECT_IS_SPECIAL(zb->zb_object)) {
375 		return (0);
376 	} else if (zb->zb_level == ZB_ZIL_LEVEL) {
377 		/*
378 		 * If we are sending a non-snapshot (which is allowed on
379 		 * read-only pools), it may have a ZIL, which must be ignored.
380 		 */
381 		return (0);
382 	} else if (BP_IS_HOLE(bp) &&
383 	    zb->zb_object == DMU_META_DNODE_OBJECT) {
384 		uint64_t span = BP_SPAN(dnp, zb->zb_level);
385 		uint64_t dnobj = (zb->zb_blkid * span) >> DNODE_SHIFT;
386 		err = dump_freeobjects(dsp, dnobj, span >> DNODE_SHIFT);
387 	} else if (BP_IS_HOLE(bp)) {
388 		uint64_t span = BP_SPAN(dnp, zb->zb_level);
389 		err = dump_free(dsp, zb->zb_object, zb->zb_blkid * span, span);
390 	} else if (zb->zb_level > 0 || type == DMU_OT_OBJSET) {
391 		return (0);
392 	} else if (type == DMU_OT_DNODE) {
393 		dnode_phys_t *blk;
394 		int i;
395 		int blksz = BP_GET_LSIZE(bp);
396 		uint32_t aflags = ARC_WAIT;
397 		arc_buf_t *abuf;
398 
399 		if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
400 		    ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
401 		    &aflags, zb) != 0)
402 			return (SET_ERROR(EIO));
403 
404 		blk = abuf->b_data;
405 		for (i = 0; i < blksz >> DNODE_SHIFT; i++) {
406 			uint64_t dnobj = (zb->zb_blkid <<
407 			    (DNODE_BLOCK_SHIFT - DNODE_SHIFT)) + i;
408 			err = dump_dnode(dsp, dnobj, blk+i);
409 			if (err != 0)
410 				break;
411 		}
412 		(void) arc_buf_remove_ref(abuf, &abuf);
413 	} else if (type == DMU_OT_SA) {
414 		uint32_t aflags = ARC_WAIT;
415 		arc_buf_t *abuf;
416 		int blksz = BP_GET_LSIZE(bp);
417 
418 		if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
419 		    ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
420 		    &aflags, zb) != 0)
421 			return (SET_ERROR(EIO));
422 
423 		err = dump_spill(dsp, zb->zb_object, blksz, abuf->b_data);
424 		(void) arc_buf_remove_ref(abuf, &abuf);
425 	} else { /* it's a level-0 block of a regular object */
426 		uint32_t aflags = ARC_WAIT;
427 		arc_buf_t *abuf;
428 		int blksz = BP_GET_LSIZE(bp);
429 
430 		ASSERT0(zb->zb_level);
431 		if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
432 		    ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
433 		    &aflags, zb) != 0) {
434 			if (zfs_send_corrupt_data) {
435 				/* Send a block filled with 0x"zfs badd bloc" */
436 				abuf = arc_buf_alloc(spa, blksz, &abuf,
437 				    ARC_BUFC_DATA);
438 				uint64_t *ptr;
439 				for (ptr = abuf->b_data;
440 				    (char *)ptr < (char *)abuf->b_data + blksz;
441 				    ptr++)
442 					*ptr = 0x2f5baddb10c;
443 			} else {
444 				return (SET_ERROR(EIO));
445 			}
446 		}
447 
448 		err = dump_data(dsp, type, zb->zb_object, zb->zb_blkid * blksz,
449 		    blksz, bp, abuf->b_data);
450 		(void) arc_buf_remove_ref(abuf, &abuf);
451 	}
452 
453 	ASSERT(err == 0 || err == EINTR);
454 	return (err);
455 }
456 
457 /*
458  * Releases dp using the specified tag.
459  */
460 static int
dmu_send_impl(void * tag,dsl_pool_t * dp,dsl_dataset_t * ds,zfs_bookmark_phys_t * fromzb,boolean_t is_clone,int outfd,vnode_t * vp,offset_t * off)461 dmu_send_impl(void *tag, dsl_pool_t *dp, dsl_dataset_t *ds,
462 #ifdef illumos
463     zfs_bookmark_phys_t *fromzb, boolean_t is_clone, int outfd,
464     vnode_t *vp, offset_t *off)
465 #else
466     zfs_bookmark_phys_t *fromzb, boolean_t is_clone, int outfd,
467     struct file *fp, offset_t *off)
468 #endif
469 {
470 	objset_t *os;
471 	dmu_replay_record_t *drr;
472 	dmu_sendarg_t *dsp;
473 	int err;
474 	uint64_t fromtxg = 0;
475 
476 	err = dmu_objset_from_ds(ds, &os);
477 	if (err != 0) {
478 		dsl_pool_rele(dp, tag);
479 		return (err);
480 	}
481 
482 	drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
483 	drr->drr_type = DRR_BEGIN;
484 	drr->drr_u.drr_begin.drr_magic = DMU_BACKUP_MAGIC;
485 	DMU_SET_STREAM_HDRTYPE(drr->drr_u.drr_begin.drr_versioninfo,
486 	    DMU_SUBSTREAM);
487 
488 #ifdef _KERNEL
489 	if (dmu_objset_type(os) == DMU_OST_ZFS) {
490 		uint64_t version;
491 		if (zfs_get_zplprop(os, ZFS_PROP_VERSION, &version) != 0) {
492 			kmem_free(drr, sizeof (dmu_replay_record_t));
493 			dsl_pool_rele(dp, tag);
494 			return (SET_ERROR(EINVAL));
495 		}
496 		if (version >= ZPL_VERSION_SA) {
497 			DMU_SET_FEATUREFLAGS(
498 			    drr->drr_u.drr_begin.drr_versioninfo,
499 			    DMU_BACKUP_FEATURE_SA_SPILL);
500 		}
501 	}
502 #endif
503 
504 	drr->drr_u.drr_begin.drr_creation_time =
505 	    ds->ds_phys->ds_creation_time;
506 	drr->drr_u.drr_begin.drr_type = dmu_objset_type(os);
507 	if (is_clone)
508 		drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CLONE;
509 	drr->drr_u.drr_begin.drr_toguid = ds->ds_phys->ds_guid;
510 	if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
511 		drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CI_DATA;
512 
513 	if (fromzb != NULL) {
514 		drr->drr_u.drr_begin.drr_fromguid = fromzb->zbm_guid;
515 		fromtxg = fromzb->zbm_creation_txg;
516 	}
517 	dsl_dataset_name(ds, drr->drr_u.drr_begin.drr_toname);
518 	if (!dsl_dataset_is_snapshot(ds)) {
519 		(void) strlcat(drr->drr_u.drr_begin.drr_toname, "@--head--",
520 		    sizeof (drr->drr_u.drr_begin.drr_toname));
521 	}
522 
523 	dsp = kmem_zalloc(sizeof (dmu_sendarg_t), KM_SLEEP);
524 
525 	dsp->dsa_drr = drr;
526 	dsp->dsa_outfd = outfd;
527 	dsp->dsa_proc = curproc;
528 	dsp->dsa_td = curthread;
529 	dsp->dsa_fp = fp;
530 	dsp->dsa_os = os;
531 	dsp->dsa_off = off;
532 	dsp->dsa_toguid = ds->ds_phys->ds_guid;
533 	ZIO_SET_CHECKSUM(&dsp->dsa_zc, 0, 0, 0, 0);
534 	dsp->dsa_pending_op = PENDING_NONE;
535 	dsp->dsa_incremental = (fromzb != NULL);
536 
537 	mutex_enter(&ds->ds_sendstream_lock);
538 	list_insert_head(&ds->ds_sendstreams, dsp);
539 	mutex_exit(&ds->ds_sendstream_lock);
540 
541 	dsl_dataset_long_hold(ds, FTAG);
542 	dsl_pool_rele(dp, tag);
543 
544 	if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0) {
545 		err = dsp->dsa_err;
546 		goto out;
547 	}
548 
549 	err = traverse_dataset(ds, fromtxg, TRAVERSE_PRE | TRAVERSE_PREFETCH,
550 	    backup_cb, dsp);
551 
552 	if (dsp->dsa_pending_op != PENDING_NONE)
553 		if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0)
554 			err = SET_ERROR(EINTR);
555 
556 	if (err != 0) {
557 		if (err == EINTR && dsp->dsa_err != 0)
558 			err = dsp->dsa_err;
559 		goto out;
560 	}
561 
562 	bzero(drr, sizeof (dmu_replay_record_t));
563 	drr->drr_type = DRR_END;
564 	drr->drr_u.drr_end.drr_checksum = dsp->dsa_zc;
565 	drr->drr_u.drr_end.drr_toguid = dsp->dsa_toguid;
566 
567 	if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0) {
568 		err = dsp->dsa_err;
569 		goto out;
570 	}
571 
572 out:
573 	mutex_enter(&ds->ds_sendstream_lock);
574 	list_remove(&ds->ds_sendstreams, dsp);
575 	mutex_exit(&ds->ds_sendstream_lock);
576 
577 	kmem_free(drr, sizeof (dmu_replay_record_t));
578 	kmem_free(dsp, sizeof (dmu_sendarg_t));
579 
580 	dsl_dataset_long_rele(ds, FTAG);
581 
582 	return (err);
583 }
584 
585 int
dmu_send_obj(const char * pool,uint64_t tosnap,uint64_t fromsnap,int outfd,vnode_t * vp,offset_t * off)586 dmu_send_obj(const char *pool, uint64_t tosnap, uint64_t fromsnap,
587 #ifdef illumos
588     int outfd, vnode_t *vp, offset_t *off)
589 #else
590     int outfd, struct file *fp, offset_t *off)
591 #endif
592 {
593 	dsl_pool_t *dp;
594 	dsl_dataset_t *ds;
595 	dsl_dataset_t *fromds = NULL;
596 	int err;
597 
598 	err = dsl_pool_hold(pool, FTAG, &dp);
599 	if (err != 0)
600 		return (err);
601 
602 	err = dsl_dataset_hold_obj(dp, tosnap, FTAG, &ds);
603 	if (err != 0) {
604 		dsl_pool_rele(dp, FTAG);
605 		return (err);
606 	}
607 
608 	if (fromsnap != 0) {
609 		zfs_bookmark_phys_t zb;
610 		boolean_t is_clone;
611 
612 		err = dsl_dataset_hold_obj(dp, fromsnap, FTAG, &fromds);
613 		if (err != 0) {
614 			dsl_dataset_rele(ds, FTAG);
615 			dsl_pool_rele(dp, FTAG);
616 			return (err);
617 		}
618 		if (!dsl_dataset_is_before(ds, fromds, 0))
619 			err = SET_ERROR(EXDEV);
620 		zb.zbm_creation_time = fromds->ds_phys->ds_creation_time;
621 		zb.zbm_creation_txg = fromds->ds_phys->ds_creation_txg;
622 		zb.zbm_guid = fromds->ds_phys->ds_guid;
623 		is_clone = (fromds->ds_dir != ds->ds_dir);
624 		dsl_dataset_rele(fromds, FTAG);
625 		err = dmu_send_impl(FTAG, dp, ds, &zb, is_clone,
626 		    outfd, fp, off);
627 	} else {
628 		err = dmu_send_impl(FTAG, dp, ds, NULL, B_FALSE,
629 		    outfd, fp, off);
630 	}
631 	dsl_dataset_rele(ds, FTAG);
632 	return (err);
633 }
634 
635 int
dmu_send(const char * tosnap,const char * fromsnap,int outfd,vnode_t * vp,offset_t * off)636 dmu_send(const char *tosnap, const char *fromsnap,
637 #ifdef illumos
638     int outfd, vnode_t *vp, offset_t *off)
639 #else
640     int outfd, struct file *fp, offset_t *off)
641 #endif
642 {
643 	dsl_pool_t *dp;
644 	dsl_dataset_t *ds;
645 	int err;
646 	boolean_t owned = B_FALSE;
647 
648 	if (fromsnap != NULL && strpbrk(fromsnap, "@#") == NULL)
649 		return (SET_ERROR(EINVAL));
650 
651 	err = dsl_pool_hold(tosnap, FTAG, &dp);
652 	if (err != 0)
653 		return (err);
654 
655 	if (strchr(tosnap, '@') == NULL && spa_writeable(dp->dp_spa)) {
656 		/*
657 		 * We are sending a filesystem or volume.  Ensure
658 		 * that it doesn't change by owning the dataset.
659 		 */
660 		err = dsl_dataset_own(dp, tosnap, FTAG, &ds);
661 		owned = B_TRUE;
662 	} else {
663 		err = dsl_dataset_hold(dp, tosnap, FTAG, &ds);
664 	}
665 	if (err != 0) {
666 		dsl_pool_rele(dp, FTAG);
667 		return (err);
668 	}
669 
670 	if (fromsnap != NULL) {
671 		zfs_bookmark_phys_t zb;
672 		boolean_t is_clone = B_FALSE;
673 		int fsnamelen = strchr(tosnap, '@') - tosnap;
674 
675 		/*
676 		 * If the fromsnap is in a different filesystem, then
677 		 * mark the send stream as a clone.
678 		 */
679 		if (strncmp(tosnap, fromsnap, fsnamelen) != 0 ||
680 		    (fromsnap[fsnamelen] != '@' &&
681 		    fromsnap[fsnamelen] != '#')) {
682 			is_clone = B_TRUE;
683 		}
684 
685 		if (strchr(fromsnap, '@')) {
686 			dsl_dataset_t *fromds;
687 			err = dsl_dataset_hold(dp, fromsnap, FTAG, &fromds);
688 			if (err == 0) {
689 				if (!dsl_dataset_is_before(ds, fromds, 0))
690 					err = SET_ERROR(EXDEV);
691 				zb.zbm_creation_time =
692 				    fromds->ds_phys->ds_creation_time;
693 				zb.zbm_creation_txg =
694 				    fromds->ds_phys->ds_creation_txg;
695 				zb.zbm_guid = fromds->ds_phys->ds_guid;
696 				is_clone = (ds->ds_dir != fromds->ds_dir);
697 				dsl_dataset_rele(fromds, FTAG);
698 			}
699 		} else {
700 			err = dsl_bookmark_lookup(dp, fromsnap, ds, &zb);
701 		}
702 		if (err != 0) {
703 			dsl_dataset_rele(ds, FTAG);
704 			dsl_pool_rele(dp, FTAG);
705 			return (err);
706 		}
707 		err = dmu_send_impl(FTAG, dp, ds, &zb, is_clone,
708 		    outfd, fp, off);
709 	} else {
710 		err = dmu_send_impl(FTAG, dp, ds, NULL, B_FALSE,
711 		    outfd, fp, off);
712 	}
713 	if (owned)
714 		dsl_dataset_disown(ds, FTAG);
715 	else
716 		dsl_dataset_rele(ds, FTAG);
717 	return (err);
718 }
719 
720 int
dmu_send_estimate(dsl_dataset_t * ds,dsl_dataset_t * fromds,uint64_t * sizep)721 dmu_send_estimate(dsl_dataset_t *ds, dsl_dataset_t *fromds, uint64_t *sizep)
722 {
723 	dsl_pool_t *dp = ds->ds_dir->dd_pool;
724 	int err;
725 	uint64_t size;
726 
727 	ASSERT(dsl_pool_config_held(dp));
728 
729 	/* tosnap must be a snapshot */
730 	if (!dsl_dataset_is_snapshot(ds))
731 		return (SET_ERROR(EINVAL));
732 
733 	/* fromsnap, if provided, must be a snapshot */
734 	if (fromds != NULL && !dsl_dataset_is_snapshot(fromds))
735 		return (SET_ERROR(EINVAL));
736 
737 	/*
738 	 * fromsnap must be an earlier snapshot from the same fs as tosnap,
739 	 * or the origin's fs.
740 	 */
741 	if (fromds != NULL && !dsl_dataset_is_before(ds, fromds, 0))
742 		return (SET_ERROR(EXDEV));
743 
744 	/* Get uncompressed size estimate of changed data. */
745 	if (fromds == NULL) {
746 		size = ds->ds_phys->ds_uncompressed_bytes;
747 	} else {
748 		uint64_t used, comp;
749 		err = dsl_dataset_space_written(fromds, ds,
750 		    &used, &comp, &size);
751 		if (err != 0)
752 			return (err);
753 	}
754 
755 	/*
756 	 * Assume that space (both on-disk and in-stream) is dominated by
757 	 * data.  We will adjust for indirect blocks and the copies property,
758 	 * but ignore per-object space used (eg, dnodes and DRR_OBJECT records).
759 	 */
760 
761 	/*
762 	 * Subtract out approximate space used by indirect blocks.
763 	 * Assume most space is used by data blocks (non-indirect, non-dnode).
764 	 * Assume all blocks are recordsize.  Assume ditto blocks and
765 	 * internal fragmentation counter out compression.
766 	 *
767 	 * Therefore, space used by indirect blocks is sizeof(blkptr_t) per
768 	 * block, which we observe in practice.
769 	 */
770 	uint64_t recordsize;
771 	err = dsl_prop_get_int_ds(ds, "recordsize", &recordsize);
772 	if (err != 0)
773 		return (err);
774 	size -= size / recordsize * sizeof (blkptr_t);
775 
776 	/* Add in the space for the record associated with each block. */
777 	size += size / recordsize * sizeof (dmu_replay_record_t);
778 
779 	*sizep = size;
780 
781 	return (0);
782 }
783 
784 typedef struct dmu_recv_begin_arg {
785 	const char *drba_origin;
786 	dmu_recv_cookie_t *drba_cookie;
787 	cred_t *drba_cred;
788 	uint64_t drba_snapobj;
789 } dmu_recv_begin_arg_t;
790 
791 static int
recv_begin_check_existing_impl(dmu_recv_begin_arg_t * drba,dsl_dataset_t * ds,uint64_t fromguid)792 recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
793     uint64_t fromguid)
794 {
795 	uint64_t val;
796 	int error;
797 	dsl_pool_t *dp = ds->ds_dir->dd_pool;
798 
799 	/* temporary clone name must not exist */
800 	error = zap_lookup(dp->dp_meta_objset,
801 	    ds->ds_dir->dd_phys->dd_child_dir_zapobj, recv_clone_name,
802 	    8, 1, &val);
803 	if (error != ENOENT)
804 		return (error == 0 ? EBUSY : error);
805 
806 	/* new snapshot name must not exist */
807 	error = zap_lookup(dp->dp_meta_objset,
808 	    ds->ds_phys->ds_snapnames_zapobj, drba->drba_cookie->drc_tosnap,
809 	    8, 1, &val);
810 	if (error != ENOENT)
811 		return (error == 0 ? EEXIST : error);
812 
813 	/*
814 	 * Check snapshot limit before receiving. We'll recheck again at the
815 	 * end, but might as well abort before receiving if we're already over
816 	 * the limit.
817 	 *
818 	 * Note that we do not check the file system limit with
819 	 * dsl_dir_fscount_check because the temporary %clones don't count
820 	 * against that limit.
821 	 */
822 	error = dsl_fs_ss_limit_check(ds->ds_dir, 1, ZFS_PROP_SNAPSHOT_LIMIT,
823 	    NULL, drba->drba_cred);
824 	if (error != 0)
825 		return (error);
826 
827 	if (fromguid != 0) {
828 		dsl_dataset_t *snap;
829 		uint64_t obj = ds->ds_phys->ds_prev_snap_obj;
830 
831 		/* Find snapshot in this dir that matches fromguid. */
832 		while (obj != 0) {
833 			error = dsl_dataset_hold_obj(dp, obj, FTAG,
834 			    &snap);
835 			if (error != 0)
836 				return (SET_ERROR(ENODEV));
837 			if (snap->ds_dir != ds->ds_dir) {
838 				dsl_dataset_rele(snap, FTAG);
839 				return (SET_ERROR(ENODEV));
840 			}
841 			if (snap->ds_phys->ds_guid == fromguid)
842 				break;
843 			obj = snap->ds_phys->ds_prev_snap_obj;
844 			dsl_dataset_rele(snap, FTAG);
845 		}
846 		if (obj == 0)
847 			return (SET_ERROR(ENODEV));
848 
849 		if (drba->drba_cookie->drc_force) {
850 			drba->drba_snapobj = obj;
851 		} else {
852 			/*
853 			 * If we are not forcing, there must be no
854 			 * changes since fromsnap.
855 			 */
856 			if (dsl_dataset_modified_since_snap(ds, snap)) {
857 				dsl_dataset_rele(snap, FTAG);
858 				return (SET_ERROR(ETXTBSY));
859 			}
860 			drba->drba_snapobj = ds->ds_prev->ds_object;
861 		}
862 
863 		dsl_dataset_rele(snap, FTAG);
864 	} else {
865 		/* if full, then must be forced */
866 		if (!drba->drba_cookie->drc_force)
867 			return (SET_ERROR(EEXIST));
868 		/* start from $ORIGIN@$ORIGIN, if supported */
869 		drba->drba_snapobj = dp->dp_origin_snap != NULL ?
870 		    dp->dp_origin_snap->ds_object : 0;
871 	}
872 
873 	return (0);
874 
875 }
876 
877 static int
dmu_recv_begin_check(void * arg,dmu_tx_t * tx)878 dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
879 {
880 	dmu_recv_begin_arg_t *drba = arg;
881 	dsl_pool_t *dp = dmu_tx_pool(tx);
882 	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
883 	uint64_t fromguid = drrb->drr_fromguid;
884 	int flags = drrb->drr_flags;
885 	int error;
886 	dsl_dataset_t *ds;
887 	const char *tofs = drba->drba_cookie->drc_tofs;
888 
889 	/* already checked */
890 	ASSERT3U(drrb->drr_magic, ==, DMU_BACKUP_MAGIC);
891 
892 	if (DMU_GET_STREAM_HDRTYPE(drrb->drr_versioninfo) ==
893 	    DMU_COMPOUNDSTREAM ||
894 	    drrb->drr_type >= DMU_OST_NUMTYPES ||
895 	    ((flags & DRR_FLAG_CLONE) && drba->drba_origin == NULL))
896 		return (SET_ERROR(EINVAL));
897 
898 	/* Verify pool version supports SA if SA_SPILL feature set */
899 	if ((DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo) &
900 	    DMU_BACKUP_FEATURE_SA_SPILL) &&
901 	    spa_version(dp->dp_spa) < SPA_VERSION_SA) {
902 		return (SET_ERROR(ENOTSUP));
903 	}
904 
905 	error = dsl_dataset_hold(dp, tofs, FTAG, &ds);
906 	if (error == 0) {
907 		/* target fs already exists; recv into temp clone */
908 
909 		/* Can't recv a clone into an existing fs */
910 		if (flags & DRR_FLAG_CLONE) {
911 			dsl_dataset_rele(ds, FTAG);
912 			return (SET_ERROR(EINVAL));
913 		}
914 
915 		error = recv_begin_check_existing_impl(drba, ds, fromguid);
916 		dsl_dataset_rele(ds, FTAG);
917 	} else if (error == ENOENT) {
918 		/* target fs does not exist; must be a full backup or clone */
919 		char buf[MAXNAMELEN];
920 
921 		/*
922 		 * If it's a non-clone incremental, we are missing the
923 		 * target fs, so fail the recv.
924 		 */
925 		if (fromguid != 0 && !(flags & DRR_FLAG_CLONE))
926 			return (SET_ERROR(ENOENT));
927 
928 		/* Open the parent of tofs */
929 		ASSERT3U(strlen(tofs), <, MAXNAMELEN);
930 		(void) strlcpy(buf, tofs, strrchr(tofs, '/') - tofs + 1);
931 		error = dsl_dataset_hold(dp, buf, FTAG, &ds);
932 		if (error != 0)
933 			return (error);
934 
935 		/*
936 		 * Check filesystem and snapshot limits before receiving. We'll
937 		 * recheck snapshot limits again at the end (we create the
938 		 * filesystems and increment those counts during begin_sync).
939 		 */
940 		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
941 		    ZFS_PROP_FILESYSTEM_LIMIT, NULL, drba->drba_cred);
942 		if (error != 0) {
943 			dsl_dataset_rele(ds, FTAG);
944 			return (error);
945 		}
946 
947 		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
948 		    ZFS_PROP_SNAPSHOT_LIMIT, NULL, drba->drba_cred);
949 		if (error != 0) {
950 			dsl_dataset_rele(ds, FTAG);
951 			return (error);
952 		}
953 
954 		if (drba->drba_origin != NULL) {
955 			dsl_dataset_t *origin;
956 			error = dsl_dataset_hold(dp, drba->drba_origin,
957 			    FTAG, &origin);
958 			if (error != 0) {
959 				dsl_dataset_rele(ds, FTAG);
960 				return (error);
961 			}
962 			if (!dsl_dataset_is_snapshot(origin)) {
963 				dsl_dataset_rele(origin, FTAG);
964 				dsl_dataset_rele(ds, FTAG);
965 				return (SET_ERROR(EINVAL));
966 			}
967 			if (origin->ds_phys->ds_guid != fromguid) {
968 				dsl_dataset_rele(origin, FTAG);
969 				dsl_dataset_rele(ds, FTAG);
970 				return (SET_ERROR(ENODEV));
971 			}
972 			dsl_dataset_rele(origin, FTAG);
973 		}
974 		dsl_dataset_rele(ds, FTAG);
975 		error = 0;
976 	}
977 	return (error);
978 }
979 
980 static void
dmu_recv_begin_sync(void * arg,dmu_tx_t * tx)981 dmu_recv_begin_sync(void *arg, dmu_tx_t *tx)
982 {
983 	dmu_recv_begin_arg_t *drba = arg;
984 	dsl_pool_t *dp = dmu_tx_pool(tx);
985 	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
986 	const char *tofs = drba->drba_cookie->drc_tofs;
987 	dsl_dataset_t *ds, *newds;
988 	uint64_t dsobj;
989 	int error;
990 	uint64_t crflags;
991 
992 	crflags = (drrb->drr_flags & DRR_FLAG_CI_DATA) ?
993 	    DS_FLAG_CI_DATASET : 0;
994 
995 	error = dsl_dataset_hold(dp, tofs, FTAG, &ds);
996 	if (error == 0) {
997 		/* create temporary clone */
998 		dsl_dataset_t *snap = NULL;
999 		if (drba->drba_snapobj != 0) {
1000 			VERIFY0(dsl_dataset_hold_obj(dp,
1001 			    drba->drba_snapobj, FTAG, &snap));
1002 		}
1003 		dsobj = dsl_dataset_create_sync(ds->ds_dir, recv_clone_name,
1004 		    snap, crflags, drba->drba_cred, tx);
1005 		if (drba->drba_snapobj != 0)
1006 			dsl_dataset_rele(snap, FTAG);
1007 		dsl_dataset_rele(ds, FTAG);
1008 	} else {
1009 		dsl_dir_t *dd;
1010 		const char *tail;
1011 		dsl_dataset_t *origin = NULL;
1012 
1013 		VERIFY0(dsl_dir_hold(dp, tofs, FTAG, &dd, &tail));
1014 
1015 		if (drba->drba_origin != NULL) {
1016 			VERIFY0(dsl_dataset_hold(dp, drba->drba_origin,
1017 			    FTAG, &origin));
1018 		}
1019 
1020 		/* Create new dataset. */
1021 		dsobj = dsl_dataset_create_sync(dd,
1022 		    strrchr(tofs, '/') + 1,
1023 		    origin, crflags, drba->drba_cred, tx);
1024 		if (origin != NULL)
1025 			dsl_dataset_rele(origin, FTAG);
1026 		dsl_dir_rele(dd, FTAG);
1027 		drba->drba_cookie->drc_newfs = B_TRUE;
1028 	}
1029 	VERIFY0(dsl_dataset_own_obj(dp, dsobj, dmu_recv_tag, &newds));
1030 
1031 	dmu_buf_will_dirty(newds->ds_dbuf, tx);
1032 	newds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT;
1033 
1034 	/*
1035 	 * If we actually created a non-clone, we need to create the
1036 	 * objset in our new dataset.
1037 	 */
1038 	if (BP_IS_HOLE(dsl_dataset_get_blkptr(newds))) {
1039 		(void) dmu_objset_create_impl(dp->dp_spa,
1040 		    newds, dsl_dataset_get_blkptr(newds), drrb->drr_type, tx);
1041 	}
1042 
1043 	drba->drba_cookie->drc_ds = newds;
1044 
1045 	spa_history_log_internal_ds(newds, "receive", tx, "");
1046 }
1047 
1048 /*
1049  * NB: callers *MUST* call dmu_recv_stream() if dmu_recv_begin()
1050  * succeeds; otherwise we will leak the holds on the datasets.
1051  */
1052 int
dmu_recv_begin(char * tofs,char * tosnap,struct drr_begin * drrb,boolean_t force,char * origin,dmu_recv_cookie_t * drc)1053 dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
1054     boolean_t force, char *origin, dmu_recv_cookie_t *drc)
1055 {
1056 	dmu_recv_begin_arg_t drba = { 0 };
1057 	dmu_replay_record_t *drr;
1058 
1059 	bzero(drc, sizeof (dmu_recv_cookie_t));
1060 	drc->drc_drrb = drrb;
1061 	drc->drc_tosnap = tosnap;
1062 	drc->drc_tofs = tofs;
1063 	drc->drc_force = force;
1064 	drc->drc_cred = CRED();
1065 
1066 	if (drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC))
1067 		drc->drc_byteswap = B_TRUE;
1068 	else if (drrb->drr_magic != DMU_BACKUP_MAGIC)
1069 		return (SET_ERROR(EINVAL));
1070 
1071 	drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
1072 	drr->drr_type = DRR_BEGIN;
1073 	drr->drr_u.drr_begin = *drc->drc_drrb;
1074 	if (drc->drc_byteswap) {
1075 		fletcher_4_incremental_byteswap(drr,
1076 		    sizeof (dmu_replay_record_t), &drc->drc_cksum);
1077 	} else {
1078 		fletcher_4_incremental_native(drr,
1079 		    sizeof (dmu_replay_record_t), &drc->drc_cksum);
1080 	}
1081 	kmem_free(drr, sizeof (dmu_replay_record_t));
1082 
1083 	if (drc->drc_byteswap) {
1084 		drrb->drr_magic = BSWAP_64(drrb->drr_magic);
1085 		drrb->drr_versioninfo = BSWAP_64(drrb->drr_versioninfo);
1086 		drrb->drr_creation_time = BSWAP_64(drrb->drr_creation_time);
1087 		drrb->drr_type = BSWAP_32(drrb->drr_type);
1088 		drrb->drr_toguid = BSWAP_64(drrb->drr_toguid);
1089 		drrb->drr_fromguid = BSWAP_64(drrb->drr_fromguid);
1090 	}
1091 
1092 	drba.drba_origin = origin;
1093 	drba.drba_cookie = drc;
1094 	drba.drba_cred = CRED();
1095 
1096 	return (dsl_sync_task(tofs, dmu_recv_begin_check, dmu_recv_begin_sync,
1097 	    &drba, 5));
1098 }
1099 
1100 struct restorearg {
1101 	int err;
1102 	boolean_t byteswap;
1103 	kthread_t *td;
1104 	struct file *fp;
1105 	char *buf;
1106 	uint64_t voff;
1107 	int bufsize; /* amount of memory allocated for buf */
1108 	zio_cksum_t cksum;
1109 	avl_tree_t *guid_to_ds_map;
1110 };
1111 
1112 typedef struct guid_map_entry {
1113 	uint64_t	guid;
1114 	dsl_dataset_t	*gme_ds;
1115 	avl_node_t	avlnode;
1116 } guid_map_entry_t;
1117 
1118 static int
guid_compare(const void * arg1,const void * arg2)1119 guid_compare(const void *arg1, const void *arg2)
1120 {
1121 	const guid_map_entry_t *gmep1 = arg1;
1122 	const guid_map_entry_t *gmep2 = arg2;
1123 
1124 	if (gmep1->guid < gmep2->guid)
1125 		return (-1);
1126 	else if (gmep1->guid > gmep2->guid)
1127 		return (1);
1128 	return (0);
1129 }
1130 
1131 static void
free_guid_map_onexit(void * arg)1132 free_guid_map_onexit(void *arg)
1133 {
1134 	avl_tree_t *ca = arg;
1135 	void *cookie = NULL;
1136 	guid_map_entry_t *gmep;
1137 
1138 	while ((gmep = avl_destroy_nodes(ca, &cookie)) != NULL) {
1139 		dsl_dataset_long_rele(gmep->gme_ds, gmep);
1140 		dsl_dataset_rele(gmep->gme_ds, gmep);
1141 		kmem_free(gmep, sizeof (guid_map_entry_t));
1142 	}
1143 	avl_destroy(ca);
1144 	kmem_free(ca, sizeof (avl_tree_t));
1145 }
1146 
1147 static int
restore_bytes(struct restorearg * ra,void * buf,int len,off_t off,ssize_t * resid)1148 restore_bytes(struct restorearg *ra, void *buf, int len, off_t off, ssize_t *resid)
1149 {
1150 	struct uio auio;
1151 	struct iovec aiov;
1152 	int error;
1153 
1154 	aiov.iov_base = buf;
1155 	aiov.iov_len = len;
1156 	auio.uio_iov = &aiov;
1157 	auio.uio_iovcnt = 1;
1158 	auio.uio_resid = len;
1159 	auio.uio_segflg = UIO_SYSSPACE;
1160 	auio.uio_rw = UIO_READ;
1161 	auio.uio_offset = off;
1162 	auio.uio_td = ra->td;
1163 #ifdef _KERNEL
1164 	error = fo_read(ra->fp, &auio, ra->td->td_ucred, FOF_OFFSET, ra->td);
1165 #else
1166 	fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__);
1167 	error = EOPNOTSUPP;
1168 #endif
1169 	*resid = auio.uio_resid;
1170 	return (error);
1171 }
1172 
1173 static void *
restore_read(struct restorearg * ra,int len)1174 restore_read(struct restorearg *ra, int len)
1175 {
1176 	void *rv;
1177 	int done = 0;
1178 
1179 	/* some things will require 8-byte alignment, so everything must */
1180 	ASSERT0(len % 8);
1181 
1182 	while (done < len) {
1183 		ssize_t resid;
1184 
1185 		ra->err = restore_bytes(ra, (caddr_t)ra->buf + done,
1186 		    len - done, ra->voff, &resid);
1187 
1188 		if (resid == len - done)
1189 			ra->err = SET_ERROR(EINVAL);
1190 		ra->voff += len - done - resid;
1191 		done = len - resid;
1192 		if (ra->err != 0)
1193 			return (NULL);
1194 	}
1195 
1196 	ASSERT3U(done, ==, len);
1197 	rv = ra->buf;
1198 	if (ra->byteswap)
1199 		fletcher_4_incremental_byteswap(rv, len, &ra->cksum);
1200 	else
1201 		fletcher_4_incremental_native(rv, len, &ra->cksum);
1202 	return (rv);
1203 }
1204 
1205 static void
backup_byteswap(dmu_replay_record_t * drr)1206 backup_byteswap(dmu_replay_record_t *drr)
1207 {
1208 #define	DO64(X) (drr->drr_u.X = BSWAP_64(drr->drr_u.X))
1209 #define	DO32(X) (drr->drr_u.X = BSWAP_32(drr->drr_u.X))
1210 	drr->drr_type = BSWAP_32(drr->drr_type);
1211 	drr->drr_payloadlen = BSWAP_32(drr->drr_payloadlen);
1212 	switch (drr->drr_type) {
1213 	case DRR_BEGIN:
1214 		DO64(drr_begin.drr_magic);
1215 		DO64(drr_begin.drr_versioninfo);
1216 		DO64(drr_begin.drr_creation_time);
1217 		DO32(drr_begin.drr_type);
1218 		DO32(drr_begin.drr_flags);
1219 		DO64(drr_begin.drr_toguid);
1220 		DO64(drr_begin.drr_fromguid);
1221 		break;
1222 	case DRR_OBJECT:
1223 		DO64(drr_object.drr_object);
1224 		/* DO64(drr_object.drr_allocation_txg); */
1225 		DO32(drr_object.drr_type);
1226 		DO32(drr_object.drr_bonustype);
1227 		DO32(drr_object.drr_blksz);
1228 		DO32(drr_object.drr_bonuslen);
1229 		DO64(drr_object.drr_toguid);
1230 		break;
1231 	case DRR_FREEOBJECTS:
1232 		DO64(drr_freeobjects.drr_firstobj);
1233 		DO64(drr_freeobjects.drr_numobjs);
1234 		DO64(drr_freeobjects.drr_toguid);
1235 		break;
1236 	case DRR_WRITE:
1237 		DO64(drr_write.drr_object);
1238 		DO32(drr_write.drr_type);
1239 		DO64(drr_write.drr_offset);
1240 		DO64(drr_write.drr_length);
1241 		DO64(drr_write.drr_toguid);
1242 		DO64(drr_write.drr_key.ddk_cksum.zc_word[0]);
1243 		DO64(drr_write.drr_key.ddk_cksum.zc_word[1]);
1244 		DO64(drr_write.drr_key.ddk_cksum.zc_word[2]);
1245 		DO64(drr_write.drr_key.ddk_cksum.zc_word[3]);
1246 		DO64(drr_write.drr_key.ddk_prop);
1247 		break;
1248 	case DRR_WRITE_BYREF:
1249 		DO64(drr_write_byref.drr_object);
1250 		DO64(drr_write_byref.drr_offset);
1251 		DO64(drr_write_byref.drr_length);
1252 		DO64(drr_write_byref.drr_toguid);
1253 		DO64(drr_write_byref.drr_refguid);
1254 		DO64(drr_write_byref.drr_refobject);
1255 		DO64(drr_write_byref.drr_refoffset);
1256 		DO64(drr_write_byref.drr_key.ddk_cksum.zc_word[0]);
1257 		DO64(drr_write_byref.drr_key.ddk_cksum.zc_word[1]);
1258 		DO64(drr_write_byref.drr_key.ddk_cksum.zc_word[2]);
1259 		DO64(drr_write_byref.drr_key.ddk_cksum.zc_word[3]);
1260 		DO64(drr_write_byref.drr_key.ddk_prop);
1261 		break;
1262 	case DRR_FREE:
1263 		DO64(drr_free.drr_object);
1264 		DO64(drr_free.drr_offset);
1265 		DO64(drr_free.drr_length);
1266 		DO64(drr_free.drr_toguid);
1267 		break;
1268 	case DRR_SPILL:
1269 		DO64(drr_spill.drr_object);
1270 		DO64(drr_spill.drr_length);
1271 		DO64(drr_spill.drr_toguid);
1272 		break;
1273 	case DRR_END:
1274 		DO64(drr_end.drr_checksum.zc_word[0]);
1275 		DO64(drr_end.drr_checksum.zc_word[1]);
1276 		DO64(drr_end.drr_checksum.zc_word[2]);
1277 		DO64(drr_end.drr_checksum.zc_word[3]);
1278 		DO64(drr_end.drr_toguid);
1279 		break;
1280 	}
1281 #undef DO64
1282 #undef DO32
1283 }
1284 
1285 static int
restore_object(struct restorearg * ra,objset_t * os,struct drr_object * drro)1286 restore_object(struct restorearg *ra, objset_t *os, struct drr_object *drro)
1287 {
1288 	int err;
1289 	dmu_tx_t *tx;
1290 	void *data = NULL;
1291 
1292 	if (drro->drr_type == DMU_OT_NONE ||
1293 	    !DMU_OT_IS_VALID(drro->drr_type) ||
1294 	    !DMU_OT_IS_VALID(drro->drr_bonustype) ||
1295 	    drro->drr_checksumtype >= ZIO_CHECKSUM_FUNCTIONS ||
1296 	    drro->drr_compress >= ZIO_COMPRESS_FUNCTIONS ||
1297 	    P2PHASE(drro->drr_blksz, SPA_MINBLOCKSIZE) ||
1298 	    drro->drr_blksz < SPA_MINBLOCKSIZE ||
1299 	    drro->drr_blksz > SPA_MAXBLOCKSIZE ||
1300 	    drro->drr_bonuslen > DN_MAX_BONUSLEN) {
1301 		return (SET_ERROR(EINVAL));
1302 	}
1303 
1304 	err = dmu_object_info(os, drro->drr_object, NULL);
1305 
1306 	if (err != 0 && err != ENOENT)
1307 		return (SET_ERROR(EINVAL));
1308 
1309 	if (drro->drr_bonuslen) {
1310 		data = restore_read(ra, P2ROUNDUP(drro->drr_bonuslen, 8));
1311 		if (ra->err != 0)
1312 			return (ra->err);
1313 	}
1314 
1315 	if (err == ENOENT) {
1316 		/* currently free, want to be allocated */
1317 		tx = dmu_tx_create(os);
1318 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1319 		err = dmu_tx_assign(tx, TXG_WAIT);
1320 		if (err != 0) {
1321 			dmu_tx_abort(tx);
1322 			return (err);
1323 		}
1324 		err = dmu_object_claim(os, drro->drr_object,
1325 		    drro->drr_type, drro->drr_blksz,
1326 		    drro->drr_bonustype, drro->drr_bonuslen, tx);
1327 		dmu_tx_commit(tx);
1328 	} else {
1329 		/* currently allocated, want to be allocated */
1330 		err = dmu_object_reclaim(os, drro->drr_object,
1331 		    drro->drr_type, drro->drr_blksz,
1332 		    drro->drr_bonustype, drro->drr_bonuslen);
1333 	}
1334 	if (err != 0) {
1335 		return (SET_ERROR(EINVAL));
1336 	}
1337 
1338 	tx = dmu_tx_create(os);
1339 	dmu_tx_hold_bonus(tx, drro->drr_object);
1340 	err = dmu_tx_assign(tx, TXG_WAIT);
1341 	if (err != 0) {
1342 		dmu_tx_abort(tx);
1343 		return (err);
1344 	}
1345 
1346 	dmu_object_set_checksum(os, drro->drr_object, drro->drr_checksumtype,
1347 	    tx);
1348 	dmu_object_set_compress(os, drro->drr_object, drro->drr_compress, tx);
1349 
1350 	if (data != NULL) {
1351 		dmu_buf_t *db;
1352 
1353 		VERIFY(0 == dmu_bonus_hold(os, drro->drr_object, FTAG, &db));
1354 		dmu_buf_will_dirty(db, tx);
1355 
1356 		ASSERT3U(db->db_size, >=, drro->drr_bonuslen);
1357 		bcopy(data, db->db_data, drro->drr_bonuslen);
1358 		if (ra->byteswap) {
1359 			dmu_object_byteswap_t byteswap =
1360 			    DMU_OT_BYTESWAP(drro->drr_bonustype);
1361 			dmu_ot_byteswap[byteswap].ob_func(db->db_data,
1362 			    drro->drr_bonuslen);
1363 		}
1364 		dmu_buf_rele(db, FTAG);
1365 	}
1366 	dmu_tx_commit(tx);
1367 	return (0);
1368 }
1369 
1370 /* ARGSUSED */
1371 static int
restore_freeobjects(struct restorearg * ra,objset_t * os,struct drr_freeobjects * drrfo)1372 restore_freeobjects(struct restorearg *ra, objset_t *os,
1373     struct drr_freeobjects *drrfo)
1374 {
1375 	uint64_t obj;
1376 
1377 	if (drrfo->drr_firstobj + drrfo->drr_numobjs < drrfo->drr_firstobj)
1378 		return (SET_ERROR(EINVAL));
1379 
1380 	for (obj = drrfo->drr_firstobj;
1381 	    obj < drrfo->drr_firstobj + drrfo->drr_numobjs;
1382 	    (void) dmu_object_next(os, &obj, FALSE, 0)) {
1383 		int err;
1384 
1385 		if (dmu_object_info(os, obj, NULL) != 0)
1386 			continue;
1387 
1388 		err = dmu_free_long_object(os, obj);
1389 		if (err != 0)
1390 			return (err);
1391 	}
1392 	return (0);
1393 }
1394 
1395 static int
restore_write(struct restorearg * ra,objset_t * os,struct drr_write * drrw)1396 restore_write(struct restorearg *ra, objset_t *os,
1397     struct drr_write *drrw)
1398 {
1399 	dmu_tx_t *tx;
1400 	void *data;
1401 	int err;
1402 
1403 	if (drrw->drr_offset + drrw->drr_length < drrw->drr_offset ||
1404 	    !DMU_OT_IS_VALID(drrw->drr_type))
1405 		return (SET_ERROR(EINVAL));
1406 
1407 	data = restore_read(ra, drrw->drr_length);
1408 	if (data == NULL)
1409 		return (ra->err);
1410 
1411 	if (dmu_object_info(os, drrw->drr_object, NULL) != 0)
1412 		return (SET_ERROR(EINVAL));
1413 
1414 	tx = dmu_tx_create(os);
1415 
1416 	dmu_tx_hold_write(tx, drrw->drr_object,
1417 	    drrw->drr_offset, drrw->drr_length);
1418 	err = dmu_tx_assign(tx, TXG_WAIT);
1419 	if (err != 0) {
1420 		dmu_tx_abort(tx);
1421 		return (err);
1422 	}
1423 	if (ra->byteswap) {
1424 		dmu_object_byteswap_t byteswap =
1425 		    DMU_OT_BYTESWAP(drrw->drr_type);
1426 		dmu_ot_byteswap[byteswap].ob_func(data, drrw->drr_length);
1427 	}
1428 	dmu_write(os, drrw->drr_object,
1429 	    drrw->drr_offset, drrw->drr_length, data, tx);
1430 	dmu_tx_commit(tx);
1431 	return (0);
1432 }
1433 
1434 /*
1435  * Handle a DRR_WRITE_BYREF record.  This record is used in dedup'ed
1436  * streams to refer to a copy of the data that is already on the
1437  * system because it came in earlier in the stream.  This function
1438  * finds the earlier copy of the data, and uses that copy instead of
1439  * data from the stream to fulfill this write.
1440  */
1441 static int
restore_write_byref(struct restorearg * ra,objset_t * os,struct drr_write_byref * drrwbr)1442 restore_write_byref(struct restorearg *ra, objset_t *os,
1443     struct drr_write_byref *drrwbr)
1444 {
1445 	dmu_tx_t *tx;
1446 	int err;
1447 	guid_map_entry_t gmesrch;
1448 	guid_map_entry_t *gmep;
1449 	avl_index_t	where;
1450 	objset_t *ref_os = NULL;
1451 	dmu_buf_t *dbp;
1452 
1453 	if (drrwbr->drr_offset + drrwbr->drr_length < drrwbr->drr_offset)
1454 		return (SET_ERROR(EINVAL));
1455 
1456 	/*
1457 	 * If the GUID of the referenced dataset is different from the
1458 	 * GUID of the target dataset, find the referenced dataset.
1459 	 */
1460 	if (drrwbr->drr_toguid != drrwbr->drr_refguid) {
1461 		gmesrch.guid = drrwbr->drr_refguid;
1462 		if ((gmep = avl_find(ra->guid_to_ds_map, &gmesrch,
1463 		    &where)) == NULL) {
1464 			return (SET_ERROR(EINVAL));
1465 		}
1466 		if (dmu_objset_from_ds(gmep->gme_ds, &ref_os))
1467 			return (SET_ERROR(EINVAL));
1468 	} else {
1469 		ref_os = os;
1470 	}
1471 
1472 	if (err = dmu_buf_hold(ref_os, drrwbr->drr_refobject,
1473 	    drrwbr->drr_refoffset, FTAG, &dbp, DMU_READ_PREFETCH))
1474 		return (err);
1475 
1476 	tx = dmu_tx_create(os);
1477 
1478 	dmu_tx_hold_write(tx, drrwbr->drr_object,
1479 	    drrwbr->drr_offset, drrwbr->drr_length);
1480 	err = dmu_tx_assign(tx, TXG_WAIT);
1481 	if (err != 0) {
1482 		dmu_tx_abort(tx);
1483 		return (err);
1484 	}
1485 	dmu_write(os, drrwbr->drr_object,
1486 	    drrwbr->drr_offset, drrwbr->drr_length, dbp->db_data, tx);
1487 	dmu_buf_rele(dbp, FTAG);
1488 	dmu_tx_commit(tx);
1489 	return (0);
1490 }
1491 
1492 static int
restore_spill(struct restorearg * ra,objset_t * os,struct drr_spill * drrs)1493 restore_spill(struct restorearg *ra, objset_t *os, struct drr_spill *drrs)
1494 {
1495 	dmu_tx_t *tx;
1496 	void *data;
1497 	dmu_buf_t *db, *db_spill;
1498 	int err;
1499 
1500 	if (drrs->drr_length < SPA_MINBLOCKSIZE ||
1501 	    drrs->drr_length > SPA_MAXBLOCKSIZE)
1502 		return (SET_ERROR(EINVAL));
1503 
1504 	data = restore_read(ra, drrs->drr_length);
1505 	if (data == NULL)
1506 		return (ra->err);
1507 
1508 	if (dmu_object_info(os, drrs->drr_object, NULL) != 0)
1509 		return (SET_ERROR(EINVAL));
1510 
1511 	VERIFY(0 == dmu_bonus_hold(os, drrs->drr_object, FTAG, &db));
1512 	if ((err = dmu_spill_hold_by_bonus(db, FTAG, &db_spill)) != 0) {
1513 		dmu_buf_rele(db, FTAG);
1514 		return (err);
1515 	}
1516 
1517 	tx = dmu_tx_create(os);
1518 
1519 	dmu_tx_hold_spill(tx, db->db_object);
1520 
1521 	err = dmu_tx_assign(tx, TXG_WAIT);
1522 	if (err != 0) {
1523 		dmu_buf_rele(db, FTAG);
1524 		dmu_buf_rele(db_spill, FTAG);
1525 		dmu_tx_abort(tx);
1526 		return (err);
1527 	}
1528 	dmu_buf_will_dirty(db_spill, tx);
1529 
1530 	if (db_spill->db_size < drrs->drr_length)
1531 		VERIFY(0 == dbuf_spill_set_blksz(db_spill,
1532 		    drrs->drr_length, tx));
1533 	bcopy(data, db_spill->db_data, drrs->drr_length);
1534 
1535 	dmu_buf_rele(db, FTAG);
1536 	dmu_buf_rele(db_spill, FTAG);
1537 
1538 	dmu_tx_commit(tx);
1539 	return (0);
1540 }
1541 
1542 /* ARGSUSED */
1543 static int
restore_free(struct restorearg * ra,objset_t * os,struct drr_free * drrf)1544 restore_free(struct restorearg *ra, objset_t *os,
1545     struct drr_free *drrf)
1546 {
1547 	int err;
1548 
1549 	if (drrf->drr_length != -1ULL &&
1550 	    drrf->drr_offset + drrf->drr_length < drrf->drr_offset)
1551 		return (SET_ERROR(EINVAL));
1552 
1553 	if (dmu_object_info(os, drrf->drr_object, NULL) != 0)
1554 		return (SET_ERROR(EINVAL));
1555 
1556 	err = dmu_free_long_range(os, drrf->drr_object,
1557 	    drrf->drr_offset, drrf->drr_length);
1558 	return (err);
1559 }
1560 
1561 /* used to destroy the drc_ds on error */
1562 static void
dmu_recv_cleanup_ds(dmu_recv_cookie_t * drc)1563 dmu_recv_cleanup_ds(dmu_recv_cookie_t *drc)
1564 {
1565 	char name[MAXNAMELEN];
1566 	dsl_dataset_name(drc->drc_ds, name);
1567 	dsl_dataset_disown(drc->drc_ds, dmu_recv_tag);
1568 	(void) dsl_destroy_head(name);
1569 }
1570 
1571 /*
1572  * NB: callers *must* call dmu_recv_end() if this succeeds.
1573  */
1574 int
dmu_recv_stream(dmu_recv_cookie_t * drc,struct file * fp,offset_t * voffp,int cleanup_fd,uint64_t * action_handlep)1575 dmu_recv_stream(dmu_recv_cookie_t *drc, struct file *fp, offset_t *voffp,
1576     int cleanup_fd, uint64_t *action_handlep)
1577 {
1578 	struct restorearg ra = { 0 };
1579 	dmu_replay_record_t *drr;
1580 	objset_t *os;
1581 	zio_cksum_t pcksum;
1582 	int featureflags;
1583 
1584 	ra.byteswap = drc->drc_byteswap;
1585 	ra.cksum = drc->drc_cksum;
1586 	ra.td = curthread;
1587 	ra.fp = fp;
1588 	ra.voff = *voffp;
1589 	ra.bufsize = 1<<20;
1590 	ra.buf = kmem_alloc(ra.bufsize, KM_SLEEP);
1591 
1592 	/* these were verified in dmu_recv_begin */
1593 	ASSERT3U(DMU_GET_STREAM_HDRTYPE(drc->drc_drrb->drr_versioninfo), ==,
1594 	    DMU_SUBSTREAM);
1595 	ASSERT3U(drc->drc_drrb->drr_type, <, DMU_OST_NUMTYPES);
1596 
1597 	/*
1598 	 * Open the objset we are modifying.
1599 	 */
1600 	VERIFY0(dmu_objset_from_ds(drc->drc_ds, &os));
1601 
1602 	ASSERT(drc->drc_ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT);
1603 
1604 	featureflags = DMU_GET_FEATUREFLAGS(drc->drc_drrb->drr_versioninfo);
1605 
1606 	/* if this stream is dedup'ed, set up the avl tree for guid mapping */
1607 	if (featureflags & DMU_BACKUP_FEATURE_DEDUP) {
1608 		minor_t minor;
1609 
1610 		if (cleanup_fd == -1) {
1611 			ra.err = SET_ERROR(EBADF);
1612 			goto out;
1613 		}
1614 		ra.err = zfs_onexit_fd_hold(cleanup_fd, &minor);
1615 		if (ra.err != 0) {
1616 			cleanup_fd = -1;
1617 			goto out;
1618 		}
1619 
1620 		if (*action_handlep == 0) {
1621 			ra.guid_to_ds_map =
1622 			    kmem_alloc(sizeof (avl_tree_t), KM_SLEEP);
1623 			avl_create(ra.guid_to_ds_map, guid_compare,
1624 			    sizeof (guid_map_entry_t),
1625 			    offsetof(guid_map_entry_t, avlnode));
1626 			ra.err = zfs_onexit_add_cb(minor,
1627 			    free_guid_map_onexit, ra.guid_to_ds_map,
1628 			    action_handlep);
1629 			if (ra.err != 0)
1630 				goto out;
1631 		} else {
1632 			ra.err = zfs_onexit_cb_data(minor, *action_handlep,
1633 			    (void **)&ra.guid_to_ds_map);
1634 			if (ra.err != 0)
1635 				goto out;
1636 		}
1637 
1638 		drc->drc_guid_to_ds_map = ra.guid_to_ds_map;
1639 	}
1640 
1641 	/*
1642 	 * Read records and process them.
1643 	 */
1644 	pcksum = ra.cksum;
1645 	while (ra.err == 0 &&
1646 	    NULL != (drr = restore_read(&ra, sizeof (*drr)))) {
1647 		if (issig(JUSTLOOKING) && issig(FORREAL)) {
1648 			ra.err = SET_ERROR(EINTR);
1649 			goto out;
1650 		}
1651 
1652 		if (ra.byteswap)
1653 			backup_byteswap(drr);
1654 
1655 		switch (drr->drr_type) {
1656 		case DRR_OBJECT:
1657 		{
1658 			/*
1659 			 * We need to make a copy of the record header,
1660 			 * because restore_{object,write} may need to
1661 			 * restore_read(), which will invalidate drr.
1662 			 */
1663 			struct drr_object drro = drr->drr_u.drr_object;
1664 			ra.err = restore_object(&ra, os, &drro);
1665 			break;
1666 		}
1667 		case DRR_FREEOBJECTS:
1668 		{
1669 			struct drr_freeobjects drrfo =
1670 			    drr->drr_u.drr_freeobjects;
1671 			ra.err = restore_freeobjects(&ra, os, &drrfo);
1672 			break;
1673 		}
1674 		case DRR_WRITE:
1675 		{
1676 			struct drr_write drrw = drr->drr_u.drr_write;
1677 			ra.err = restore_write(&ra, os, &drrw);
1678 			break;
1679 		}
1680 		case DRR_WRITE_BYREF:
1681 		{
1682 			struct drr_write_byref drrwbr =
1683 			    drr->drr_u.drr_write_byref;
1684 			ra.err = restore_write_byref(&ra, os, &drrwbr);
1685 			break;
1686 		}
1687 		case DRR_FREE:
1688 		{
1689 			struct drr_free drrf = drr->drr_u.drr_free;
1690 			ra.err = restore_free(&ra, os, &drrf);
1691 			break;
1692 		}
1693 		case DRR_END:
1694 		{
1695 			struct drr_end drre = drr->drr_u.drr_end;
1696 			/*
1697 			 * We compare against the *previous* checksum
1698 			 * value, because the stored checksum is of
1699 			 * everything before the DRR_END record.
1700 			 */
1701 			if (!ZIO_CHECKSUM_EQUAL(drre.drr_checksum, pcksum))
1702 				ra.err = SET_ERROR(ECKSUM);
1703 			goto out;
1704 		}
1705 		case DRR_SPILL:
1706 		{
1707 			struct drr_spill drrs = drr->drr_u.drr_spill;
1708 			ra.err = restore_spill(&ra, os, &drrs);
1709 			break;
1710 		}
1711 		default:
1712 			ra.err = SET_ERROR(EINVAL);
1713 			goto out;
1714 		}
1715 		pcksum = ra.cksum;
1716 	}
1717 	ASSERT(ra.err != 0);
1718 
1719 out:
1720 	if ((featureflags & DMU_BACKUP_FEATURE_DEDUP) && (cleanup_fd != -1))
1721 		zfs_onexit_fd_rele(cleanup_fd);
1722 
1723 	if (ra.err != 0) {
1724 		/*
1725 		 * destroy what we created, so we don't leave it in the
1726 		 * inconsistent restoring state.
1727 		 */
1728 		dmu_recv_cleanup_ds(drc);
1729 	}
1730 
1731 	kmem_free(ra.buf, ra.bufsize);
1732 	*voffp = ra.voff;
1733 	return (ra.err);
1734 }
1735 
1736 static int
dmu_recv_end_check(void * arg,dmu_tx_t * tx)1737 dmu_recv_end_check(void *arg, dmu_tx_t *tx)
1738 {
1739 	dmu_recv_cookie_t *drc = arg;
1740 	dsl_pool_t *dp = dmu_tx_pool(tx);
1741 	int error;
1742 
1743 	ASSERT3P(drc->drc_ds->ds_owner, ==, dmu_recv_tag);
1744 
1745 	if (!drc->drc_newfs) {
1746 		dsl_dataset_t *origin_head;
1747 
1748 		error = dsl_dataset_hold(dp, drc->drc_tofs, FTAG, &origin_head);
1749 		if (error != 0)
1750 			return (error);
1751 		if (drc->drc_force) {
1752 			/*
1753 			 * We will destroy any snapshots in tofs (i.e. before
1754 			 * origin_head) that are after the origin (which is
1755 			 * the snap before drc_ds, because drc_ds can not
1756 			 * have any snaps of its own).
1757 			 */
1758 			uint64_t obj = origin_head->ds_phys->ds_prev_snap_obj;
1759 			while (obj != drc->drc_ds->ds_phys->ds_prev_snap_obj) {
1760 				dsl_dataset_t *snap;
1761 				error = dsl_dataset_hold_obj(dp, obj, FTAG,
1762 				    &snap);
1763 				if (error != 0)
1764 					break;
1765 				if (snap->ds_dir != origin_head->ds_dir)
1766 					error = SET_ERROR(EINVAL);
1767 				if (error == 0)  {
1768 					error = dsl_destroy_snapshot_check_impl(
1769 					    snap, B_FALSE);
1770 				}
1771 				obj = snap->ds_phys->ds_prev_snap_obj;
1772 				dsl_dataset_rele(snap, FTAG);
1773 				if (error != 0)
1774 					break;
1775 			}
1776 			if (error != 0) {
1777 				dsl_dataset_rele(origin_head, FTAG);
1778 				return (error);
1779 			}
1780 		}
1781 		error = dsl_dataset_clone_swap_check_impl(drc->drc_ds,
1782 		    origin_head, drc->drc_force, drc->drc_owner, tx);
1783 		if (error != 0) {
1784 			dsl_dataset_rele(origin_head, FTAG);
1785 			return (error);
1786 		}
1787 		error = dsl_dataset_snapshot_check_impl(origin_head,
1788 		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
1789 		dsl_dataset_rele(origin_head, FTAG);
1790 		if (error != 0)
1791 			return (error);
1792 
1793 		error = dsl_destroy_head_check_impl(drc->drc_ds, 1);
1794 	} else {
1795 		error = dsl_dataset_snapshot_check_impl(drc->drc_ds,
1796 		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
1797 	}
1798 	return (error);
1799 }
1800 
1801 static void
dmu_recv_end_sync(void * arg,dmu_tx_t * tx)1802 dmu_recv_end_sync(void *arg, dmu_tx_t *tx)
1803 {
1804 	dmu_recv_cookie_t *drc = arg;
1805 	dsl_pool_t *dp = dmu_tx_pool(tx);
1806 
1807 	spa_history_log_internal_ds(drc->drc_ds, "finish receiving",
1808 	    tx, "snap=%s", drc->drc_tosnap);
1809 
1810 	if (!drc->drc_newfs) {
1811 		dsl_dataset_t *origin_head;
1812 
1813 		VERIFY0(dsl_dataset_hold(dp, drc->drc_tofs, FTAG,
1814 		    &origin_head));
1815 
1816 		if (drc->drc_force) {
1817 			/*
1818 			 * Destroy any snapshots of drc_tofs (origin_head)
1819 			 * after the origin (the snap before drc_ds).
1820 			 */
1821 			uint64_t obj = origin_head->ds_phys->ds_prev_snap_obj;
1822 			while (obj != drc->drc_ds->ds_phys->ds_prev_snap_obj) {
1823 				dsl_dataset_t *snap;
1824 				VERIFY0(dsl_dataset_hold_obj(dp, obj, FTAG,
1825 				    &snap));
1826 				ASSERT3P(snap->ds_dir, ==, origin_head->ds_dir);
1827 				obj = snap->ds_phys->ds_prev_snap_obj;
1828 				dsl_destroy_snapshot_sync_impl(snap,
1829 				    B_FALSE, tx);
1830 				dsl_dataset_rele(snap, FTAG);
1831 			}
1832 		}
1833 		VERIFY3P(drc->drc_ds->ds_prev, ==,
1834 		    origin_head->ds_prev);
1835 
1836 		dsl_dataset_clone_swap_sync_impl(drc->drc_ds,
1837 		    origin_head, tx);
1838 		dsl_dataset_snapshot_sync_impl(origin_head,
1839 		    drc->drc_tosnap, tx);
1840 
1841 		/* set snapshot's creation time and guid */
1842 		dmu_buf_will_dirty(origin_head->ds_prev->ds_dbuf, tx);
1843 		origin_head->ds_prev->ds_phys->ds_creation_time =
1844 		    drc->drc_drrb->drr_creation_time;
1845 		origin_head->ds_prev->ds_phys->ds_guid =
1846 		    drc->drc_drrb->drr_toguid;
1847 		origin_head->ds_prev->ds_phys->ds_flags &=
1848 		    ~DS_FLAG_INCONSISTENT;
1849 
1850 		dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
1851 		origin_head->ds_phys->ds_flags &= ~DS_FLAG_INCONSISTENT;
1852 
1853 		dsl_dataset_rele(origin_head, FTAG);
1854 		dsl_destroy_head_sync_impl(drc->drc_ds, tx);
1855 
1856 		if (drc->drc_owner != NULL)
1857 			VERIFY3P(origin_head->ds_owner, ==, drc->drc_owner);
1858 	} else {
1859 		dsl_dataset_t *ds = drc->drc_ds;
1860 
1861 		dsl_dataset_snapshot_sync_impl(ds, drc->drc_tosnap, tx);
1862 
1863 		/* set snapshot's creation time and guid */
1864 		dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1865 		ds->ds_prev->ds_phys->ds_creation_time =
1866 		    drc->drc_drrb->drr_creation_time;
1867 		ds->ds_prev->ds_phys->ds_guid = drc->drc_drrb->drr_toguid;
1868 		ds->ds_prev->ds_phys->ds_flags &= ~DS_FLAG_INCONSISTENT;
1869 
1870 		dmu_buf_will_dirty(ds->ds_dbuf, tx);
1871 		ds->ds_phys->ds_flags &= ~DS_FLAG_INCONSISTENT;
1872 	}
1873 	drc->drc_newsnapobj = drc->drc_ds->ds_phys->ds_prev_snap_obj;
1874 	/*
1875 	 * Release the hold from dmu_recv_begin.  This must be done before
1876 	 * we return to open context, so that when we free the dataset's dnode,
1877 	 * we can evict its bonus buffer.
1878 	 */
1879 	dsl_dataset_disown(drc->drc_ds, dmu_recv_tag);
1880 	drc->drc_ds = NULL;
1881 }
1882 
1883 static int
add_ds_to_guidmap(const char * name,avl_tree_t * guid_map,uint64_t snapobj)1884 add_ds_to_guidmap(const char *name, avl_tree_t *guid_map, uint64_t snapobj)
1885 {
1886 	dsl_pool_t *dp;
1887 	dsl_dataset_t *snapds;
1888 	guid_map_entry_t *gmep;
1889 	int err;
1890 
1891 	ASSERT(guid_map != NULL);
1892 
1893 	err = dsl_pool_hold(name, FTAG, &dp);
1894 	if (err != 0)
1895 		return (err);
1896 	gmep = kmem_alloc(sizeof (*gmep), KM_SLEEP);
1897 	err = dsl_dataset_hold_obj(dp, snapobj, gmep, &snapds);
1898 	if (err == 0) {
1899 		gmep->guid = snapds->ds_phys->ds_guid;
1900 		gmep->gme_ds = snapds;
1901 		avl_add(guid_map, gmep);
1902 		dsl_dataset_long_hold(snapds, gmep);
1903 	} else
1904 		kmem_free(gmep, sizeof (*gmep));
1905 
1906 	dsl_pool_rele(dp, FTAG);
1907 	return (err);
1908 }
1909 
1910 static int dmu_recv_end_modified_blocks = 3;
1911 
1912 static int
dmu_recv_existing_end(dmu_recv_cookie_t * drc)1913 dmu_recv_existing_end(dmu_recv_cookie_t *drc)
1914 {
1915 	int error;
1916 	char name[MAXNAMELEN];
1917 
1918 #ifdef _KERNEL
1919 	/*
1920 	 * We will be destroying the ds; make sure its origin is unmounted if
1921 	 * necessary.
1922 	 */
1923 	dsl_dataset_name(drc->drc_ds, name);
1924 	zfs_destroy_unmount_origin(name);
1925 #endif
1926 
1927 	error = dsl_sync_task(drc->drc_tofs,
1928 	    dmu_recv_end_check, dmu_recv_end_sync, drc,
1929 	    dmu_recv_end_modified_blocks);
1930 
1931 	if (error != 0)
1932 		dmu_recv_cleanup_ds(drc);
1933 	return (error);
1934 }
1935 
1936 static int
dmu_recv_new_end(dmu_recv_cookie_t * drc)1937 dmu_recv_new_end(dmu_recv_cookie_t *drc)
1938 {
1939 	int error;
1940 
1941 	error = dsl_sync_task(drc->drc_tofs,
1942 	    dmu_recv_end_check, dmu_recv_end_sync, drc,
1943 	    dmu_recv_end_modified_blocks);
1944 
1945 	if (error != 0) {
1946 		dmu_recv_cleanup_ds(drc);
1947 	} else if (drc->drc_guid_to_ds_map != NULL) {
1948 		(void) add_ds_to_guidmap(drc->drc_tofs,
1949 		    drc->drc_guid_to_ds_map,
1950 		    drc->drc_newsnapobj);
1951 	}
1952 	return (error);
1953 }
1954 
1955 int
dmu_recv_end(dmu_recv_cookie_t * drc,void * owner)1956 dmu_recv_end(dmu_recv_cookie_t *drc, void *owner)
1957 {
1958 	drc->drc_owner = owner;
1959 
1960 	if (drc->drc_newfs)
1961 		return (dmu_recv_new_end(drc));
1962 	else
1963 		return (dmu_recv_existing_end(drc));
1964 }
1965 
1966 /*
1967  * Return TRUE if this objset is currently being received into.
1968  */
1969 boolean_t
dmu_objset_is_receiving(objset_t * os)1970 dmu_objset_is_receiving(objset_t *os)
1971 {
1972 	return (os->os_dsl_dataset != NULL &&
1973 	    os->os_dsl_dataset->ds_owner == dmu_recv_tag);
1974 }
1975