Import illumos changeset 13686:4bc0783f6064

2703 add mechanism to report ZFS send progress

If the zfs send command is used with the -v flag, the amount of bytes
transmitted is reported in per second updates.

References:
https://www.illumos.org/issues/2703

Obtained from:	illumos (issue #2703)
MFC after:	2 weeks

12 files changed, 320 insertions, 133 deletions

diff --git a/cddl/contrib/opensolaris/cmd/zfs/zfs.8 b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
index cfdfab0..c11123a 100644
--- a/cddl/contrib/opensolaris/cmd/zfs/zfs.8
+++ b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
@@ -20,6 +20,7 @@
 .\" Copyright (c) 2010, Sun Microsystems, Inc. All Rights Reserved.
 .\" Copyright (c) 2012 by Delphix. All rights reserved.
 .\" Copyright (c) 2012 Nexenta Systems, Inc. All Rights Reserved.
+.\" Copyright (c) 2012, Joyent, Inc. All rights reserved.
 .\" Copyright (c) 2011, Pawel Jakub Dawidek <pjd@FreeBSD.org>
 .\"
 .\" $FreeBSD$
@@ -2280,6 +2281,7 @@ flags to determine what data will be sent.
 Print machine-parsable verbose information about the stream package generated.
 .It Fl v
 Print verbose information about the stream package generated.
+This information includes a per-second report of how much data has been sent.
 .El
 .Pp
 The format of the stream is committed. You will be able to receive your streams
diff --git a/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c b/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
index 0168714..7b5e7f4 100644
--- a/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
+++ b/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
@@ -24,6 +24,7 @@
  * Copyright 2012 Nexenta Systems, Inc. All rights reserved.
  * Copyright (c) 2012 by Delphix. All rights reserved.
  * Copyright 2012 Milan Jurik. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  * Copyright (c) 2011-2012 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  * Copyright (c) 2012 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
@@ -3590,6 +3591,7 @@ zfs_do_send(int argc, char **argv)
 			if (flags.verbose)
 				extraverbose = B_TRUE;
 			flags.verbose = B_TRUE;
+			flags.progress = B_TRUE;
 			break;
 		case 'D':
 			flags.dedup = B_TRUE;
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
index fb9e337..129d81e 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
@@ -25,7 +25,7 @@
  * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
- * All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
@@ -573,6 +573,9 @@ typedef struct sendflags {
 
 	/* parsable verbose output (ie. -P) */
 	boolean_t parsable;
+
+	/* show progress (ie. -v) */
+	boolean_t progress;
 } sendflags_t;
 
 typedef boolean_t (snapfilter_cb_t)(zfs_handle_t *, void *);
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_sendrecv.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_sendrecv.c
index 1a305fd..7a6418b 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_sendrecv.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_sendrecv.c
@@ -22,6 +22,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  */
@@ -40,6 +41,7 @@
 #include <sys/mount.h>
 #include <pthread.h>
 #include <umem.h>
+#include <time.h>
 
 #include <libzfs.h>
 
@@ -67,6 +69,12 @@ typedef struct dedup_arg {
 	libzfs_handle_t  *dedup_hdl;
 } dedup_arg_t;
 
+typedef struct progress_arg {
+	zfs_handle_t *pa_zhp;
+	int pa_fd;
+	boolean_t pa_parsable;
+} progress_arg_t;
+
 typedef struct dataref {
 	uint64_t ref_guid;
 	uint64_t ref_object;
@@ -786,7 +794,7 @@ typedef struct send_dump_data {
 	char prevsnap[ZFS_MAXNAMELEN];
 	uint64_t prevsnap_obj;
 	boolean_t seenfrom, seento, replicate, doall, fromorigin;
-	boolean_t verbose, dryrun, parsable;
+	boolean_t verbose, dryrun, parsable, progress;
 	int outfd;
 	boolean_t err;
 	nvlist_t *fss;
@@ -979,10 +987,60 @@ hold_for_send(zfs_handle_t *zhp, send_dump_data_t *sdd)
 	return (error);
 }
 
+static void *
+send_progress_thread(void *arg)
+{
+	progress_arg_t *pa = arg;
+
+	zfs_cmd_t zc = { 0 };
+	zfs_handle_t *zhp = pa->pa_zhp;
+	libzfs_handle_t *hdl = zhp->zfs_hdl;
+	unsigned long long bytes;
+	char buf[16];
+
+	time_t t;
+	struct tm *tm;
+
+	assert(zhp->zfs_type == ZFS_TYPE_SNAPSHOT);
+	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
+
+	if (!pa->pa_parsable)
+		(void) fprintf(stderr, "TIME        SENT   SNAPSHOT\n");
+
+	/*
+	 * Print the progress from ZFS_IOC_SEND_PROGRESS every second.
+	 */
+	for (;;) {
+		(void) sleep(1);
+
+		zc.zc_cookie = pa->pa_fd;
+		if (zfs_ioctl(hdl, ZFS_IOC_SEND_PROGRESS, &zc) != 0)
+			return ((void *)-1);
+
+		(void) time(&t);
+		tm = localtime(&t);
+		bytes = zc.zc_cookie;
+
+		if (pa->pa_parsable) {
+			(void) fprintf(stderr, "%02d:%02d:%02d\t%llu\t%s\n",
+			    tm->tm_hour, tm->tm_min, tm->tm_sec,
+			    bytes, zhp->zfs_name);
+		} else {
+			zfs_nicenum(bytes, buf, sizeof (buf));
+			(void) fprintf(stderr, "%02d:%02d:%02d   %5s   %s\n",
+			    tm->tm_hour, tm->tm_min, tm->tm_sec,
+			    buf, zhp->zfs_name);
+		}
+	}
+}
+
 static int
 dump_snapshot(zfs_handle_t *zhp, void *arg)
 {
 	send_dump_data_t *sdd = arg;
+	progress_arg_t pa = { 0 };
+	pthread_t tid;
+
 	char *thissnap;
 	int err;
 	boolean_t isfromsnap, istosnap, fromorigin;
@@ -1100,8 +1158,29 @@ dump_snapshot(zfs_handle_t *zhp, void *arg)
 	}
 
 	if (!sdd->dryrun) {
+		/*
+		 * If progress reporting is requested, spawn a new thread to
+		 * poll ZFS_IOC_SEND_PROGRESS at a regular interval.
+		 */
+		if (sdd->progress) {
+			pa.pa_zhp = zhp;
+			pa.pa_fd = sdd->outfd;
+			pa.pa_parsable = sdd->parsable;
+
+			if (err = pthread_create(&tid, NULL,
+			    send_progress_thread, &pa)) {
+				zfs_close(zhp);
+				return (err);
+			}
+		}
+
 		err = dump_ioctl(zhp, sdd->prevsnap, sdd->prevsnap_obj,
 		    fromorigin, sdd->outfd, sdd->debugnv);
+
+		if (sdd->progress) {
+			(void) pthread_cancel(tid);
+			(void) pthread_join(tid, NULL);
+		}
 	}
 
 	(void) strcpy(sdd->prevsnap, thissnap);
@@ -1451,12 +1530,13 @@ zfs_send(zfs_handle_t *zhp, const char *fromsnap, const char *tosnap,
 	sdd.fsavl = fsavl;
 	sdd.verbose = flags->verbose;
 	sdd.parsable = flags->parsable;
+	sdd.progress = flags->progress;
 	sdd.dryrun = flags->dryrun;
 	sdd.filter_cb = filter_func;
 	sdd.filter_cb_arg = cb_arg;
 	if (debugnvp)
 		sdd.debugnv = *debugnvp;
-	if (holdsnaps) {
+	if (holdsnaps || flags->progress) {
 		++holdseq;
 		(void) snprintf(sdd.holdtag, sizeof (sdd.holdtag),
 		    ".send-%d-%llu", getpid(), (u_longlong_t)holdseq);
diff --git a/cddl/contrib/opensolaris/lib/libzpool/common/sys/zfs_context.h b/cddl/contrib/opensolaris/lib/libzpool/common/sys/zfs_context.h
index fa749d5..558de2e 100644
--- a/cddl/contrib/opensolaris/lib/libzpool/common/sys/zfs_context.h
+++ b/cddl/contrib/opensolaris/lib/libzpool/common/sys/zfs_context.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
 #ifndef _SYS_ZFS_CONTEXT_H
@@ -228,6 +229,7 @@ struct proc {
 };
 
 extern struct proc p0;
+#define	curproc		(&p0)
 
 #define	PS_NONE		-1
 
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
index 5b99b30..baed037 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c
@@ -25,6 +25,8 @@
 /*
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
 #include <sys/dmu.h>
@@ -54,38 +56,15 @@ int zfs_send_corrupt_data = B_FALSE;
 
 static char *dmu_recv_tag = "dmu_recv_tag";
 
-/*
- * The list of data whose inclusion in a send stream can be pending from
- * one call to backup_cb to another.  Multiple calls to dump_free() and
- * dump_freeobjects() can be aggregated into a single DRR_FREE or
- * DRR_FREEOBJECTS replay record.
- */
-typedef enum {
-	PENDING_NONE,
-	PENDING_FREE,
-	PENDING_FREEOBJECTS
-} pendop_t;
-
-struct backuparg {
-	dmu_replay_record_t *drr;
-	kthread_t *td;
-	struct file *fp;
-	offset_t *off;
-	objset_t *os;
-	zio_cksum_t zc;
-	uint64_t toguid;
-	int err;
-	pendop_t pending_op;
-};
-
 static int
-dump_bytes(struct backuparg *ba, void *buf, int len)
+dump_bytes(dmu_sendarg_t *dsp, void *buf, int len)
 {
+	dsl_dataset_t *ds = dsp->dsa_os->os_dsl_dataset;
 	struct uio auio;
 	struct iovec aiov;
 	ASSERT3U(len % 8, ==, 0);
 
-	fletcher_4_incremental_native(buf, len, &ba->zc);
+	fletcher_4_incremental_native(buf, len, &dsp->dsa_zc);
 	aiov.iov_base = buf;
 	aiov.iov_len = len;
 	auio.uio_iov = &aiov;
@@ -94,24 +73,28 @@ dump_bytes(struct backuparg *ba, void *buf, int len)
 	auio.uio_segflg = UIO_SYSSPACE;
 	auio.uio_rw = UIO_WRITE;
 	auio.uio_offset = (off_t)-1;
-	auio.uio_td = ba->td;
+	auio.uio_td = dsp->dsa_td;
 #ifdef _KERNEL
-	if (ba->fp->f_type == DTYPE_VNODE)
+	if (dsp->dsa_fp->f_type == DTYPE_VNODE)
 		bwillwrite();
-	ba->err = fo_write(ba->fp, &auio, ba->td->td_ucred, 0, ba->td);
+	dsp->dsa_err = fo_write(dsp->dsa_fp, &auio, dsp->dsa_td->td_ucred, 0,
+	    dsp->dsa_td);
 #else
 	fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__);
-	ba->err = EOPNOTSUPP;
+	dsp->dsa_err = EOPNOTSUPP;
 #endif
-	*ba->off += len;
-	return (ba->err);
+	mutex_enter(&ds->ds_sendstream_lock);
+	*dsp->dsa_off += len;
+	mutex_exit(&ds->ds_sendstream_lock);
+
+	return (dsp->dsa_err);
 }
 
 static int
-dump_free(struct backuparg *ba, uint64_t object, uint64_t offset,
+dump_free(dmu_sendarg_t *dsp, uint64_t object, uint64_t offset,
     uint64_t length)
 {
-	struct drr_free *drrf = &(ba->drr->drr_u.drr_free);
+	struct drr_free *drrf = &(dsp->dsa_drr->drr_u.drr_free);
 
 	/*
 	 * If there is a pending op, but it's not PENDING_FREE, push it out,
@@ -120,13 +103,15 @@ dump_free(struct backuparg *ba, uint64_t object, uint64_t offset,
 	 * other DRR_FREE records.  DRR_FREEOBJECTS records can only be
 	 * aggregated with other DRR_FREEOBJECTS records.
 	 */
-	if (ba->pending_op != PENDING_NONE && ba->pending_op != PENDING_FREE) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE &&
+	    dsp->dsa_pending_op != PENDING_FREE) {
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
-		ba->pending_op = PENDING_NONE;
+		dsp->dsa_pending_op = PENDING_NONE;
 	}
 
-	if (ba->pending_op == PENDING_FREE) {
+	if (dsp->dsa_pending_op == PENDING_FREE) {
 		/*
 		 * There should never be a PENDING_FREE if length is -1
 		 * (because dump_dnode is the only place where this
@@ -144,34 +129,35 @@ dump_free(struct backuparg *ba, uint64_t object, uint64_t offset,
 			return (0);
 		} else {
 			/* not a continuation.  Push out pending record */
-			if (dump_bytes(ba, ba->drr,
+			if (dump_bytes(dsp, dsp->dsa_drr,
 			    sizeof (dmu_replay_record_t)) != 0)
 				return (EINTR);
-			ba->pending_op = PENDING_NONE;
+			dsp->dsa_pending_op = PENDING_NONE;
 		}
 	}
 	/* create a FREE record and make it pending */
-	bzero(ba->drr, sizeof (dmu_replay_record_t));
-	ba->drr->drr_type = DRR_FREE;
+	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
+	dsp->dsa_drr->drr_type = DRR_FREE;
 	drrf->drr_object = object;
 	drrf->drr_offset = offset;
 	drrf->drr_length = length;
-	drrf->drr_toguid = ba->toguid;
+	drrf->drr_toguid = dsp->dsa_toguid;
 	if (length == -1ULL) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
 	} else {
-		ba->pending_op = PENDING_FREE;
+		dsp->dsa_pending_op = PENDING_FREE;
 	}
 
 	return (0);
 }
 
 static int
-dump_data(struct backuparg *ba, dmu_object_type_t type,
+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)
 {
-	struct drr_write *drrw = &(ba->drr->drr_u.drr_write);
+	struct drr_write *drrw = &(dsp->dsa_drr->drr_u.drr_write);
 
 
 	/*
@@ -180,19 +166,20 @@ dump_data(struct backuparg *ba, dmu_object_type_t type,
 	 * the stream, since aggregation can't be done across operations
 	 * of different types.
 	 */
-	if (ba->pending_op != PENDING_NONE) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE) {
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
-		ba->pending_op = PENDING_NONE;
+		dsp->dsa_pending_op = PENDING_NONE;
 	}
 	/* write a DATA record */
-	bzero(ba->drr, sizeof (dmu_replay_record_t));
-	ba->drr->drr_type = DRR_WRITE;
+	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
+	dsp->dsa_drr->drr_type = DRR_WRITE;
 	drrw->drr_object = object;
 	drrw->drr_type = type;
 	drrw->drr_offset = offset;
 	drrw->drr_length = blksz;
-	drrw->drr_toguid = ba->toguid;
+	drrw->drr_toguid = dsp->dsa_toguid;
 	drrw->drr_checksumtype = BP_GET_CHECKSUM(bp);
 	if (zio_checksum_table[drrw->drr_checksumtype].ci_dedup)
 		drrw->drr_checksumflags |= DRR_CHECKSUM_DEDUP;
@@ -201,42 +188,43 @@ dump_data(struct backuparg *ba, dmu_object_type_t type,
 	DDK_SET_COMPRESS(&drrw->drr_key, BP_GET_COMPRESS(bp));
 	drrw->drr_key.ddk_cksum = bp->blk_cksum;
 
-	if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)) != 0)
 		return (EINTR);
-	if (dump_bytes(ba, data, blksz) != 0)
+	if (dump_bytes(dsp, data, blksz) != 0)
 		return (EINTR);
 	return (0);
 }
 
 static int
-dump_spill(struct backuparg *ba, uint64_t object, int blksz, void *data)
+dump_spill(dmu_sendarg_t *dsp, uint64_t object, int blksz, void *data)
 {
-	struct drr_spill *drrs = &(ba->drr->drr_u.drr_spill);
+	struct drr_spill *drrs = &(dsp->dsa_drr->drr_u.drr_spill);
 
-	if (ba->pending_op != PENDING_NONE) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE) {
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
-		ba->pending_op = PENDING_NONE;
+		dsp->dsa_pending_op = PENDING_NONE;
 	}
 
 	/* write a SPILL record */
-	bzero(ba->drr, sizeof (dmu_replay_record_t));
-	ba->drr->drr_type = DRR_SPILL;
+	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
+	dsp->dsa_drr->drr_type = DRR_SPILL;
 	drrs->drr_object = object;
 	drrs->drr_length = blksz;
-	drrs->drr_toguid = ba->toguid;
+	drrs->drr_toguid = dsp->dsa_toguid;
 
-	if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)))
+	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)))
 		return (EINTR);
-	if (dump_bytes(ba, data, blksz))
+	if (dump_bytes(dsp, data, blksz))
 		return (EINTR);
 	return (0);
 }
 
 static int
-dump_freeobjects(struct backuparg *ba, uint64_t firstobj, uint64_t numobjs)
+dump_freeobjects(dmu_sendarg_t *dsp, uint64_t firstobj, uint64_t numobjs)
 {
-	struct drr_freeobjects *drrfo = &(ba->drr->drr_u.drr_freeobjects);
+	struct drr_freeobjects *drrfo = &(dsp->dsa_drr->drr_u.drr_freeobjects);
 
 	/*
 	 * If there is a pending op, but it's not PENDING_FREEOBJECTS,
@@ -245,13 +233,14 @@ dump_freeobjects(struct backuparg *ba, uint64_t firstobj, uint64_t numobjs)
 	 * aggregated with other DRR_FREE records.  DRR_FREEOBJECTS records
 	 * can only be aggregated with other DRR_FREEOBJECTS records.
 	 */
-	if (ba->pending_op != PENDING_NONE &&
-	    ba->pending_op != PENDING_FREEOBJECTS) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE &&
+	    dsp->dsa_pending_op != PENDING_FREEOBJECTS) {
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
-		ba->pending_op = PENDING_NONE;
+		dsp->dsa_pending_op = PENDING_NONE;
 	}
-	if (ba->pending_op == PENDING_FREEOBJECTS) {
+	if (dsp->dsa_pending_op == PENDING_FREEOBJECTS) {
 		/*
 		 * See whether this free object array can be aggregated
 		 * with pending one
@@ -261,42 +250,43 @@ dump_freeobjects(struct backuparg *ba, uint64_t firstobj, uint64_t numobjs)
 			return (0);
 		} else {
 			/* can't be aggregated.  Push out pending record */
-			if (dump_bytes(ba, ba->drr,
+			if (dump_bytes(dsp, dsp->dsa_drr,
 			    sizeof (dmu_replay_record_t)) != 0)
 				return (EINTR);
-			ba->pending_op = PENDING_NONE;
+			dsp->dsa_pending_op = PENDING_NONE;
 		}
 	}
 
 	/* write a FREEOBJECTS record */
-	bzero(ba->drr, sizeof (dmu_replay_record_t));
-	ba->drr->drr_type = DRR_FREEOBJECTS;
+	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
+	dsp->dsa_drr->drr_type = DRR_FREEOBJECTS;
 	drrfo->drr_firstobj = firstobj;
 	drrfo->drr_numobjs = numobjs;
-	drrfo->drr_toguid = ba->toguid;
+	drrfo->drr_toguid = dsp->dsa_toguid;
 
-	ba->pending_op = PENDING_FREEOBJECTS;
+	dsp->dsa_pending_op = PENDING_FREEOBJECTS;
 
 	return (0);
 }
 
 static int
-dump_dnode(struct backuparg *ba, uint64_t object, dnode_phys_t *dnp)
+dump_dnode(dmu_sendarg_t *dsp, uint64_t object, dnode_phys_t *dnp)
 {
-	struct drr_object *drro = &(ba->drr->drr_u.drr_object);
+	struct drr_object *drro = &(dsp->dsa_drr->drr_u.drr_object);
 
 	if (dnp == NULL || dnp->dn_type == DMU_OT_NONE)
-		return (dump_freeobjects(ba, object, 1));
+		return (dump_freeobjects(dsp, object, 1));
 
-	if (ba->pending_op != PENDING_NONE) {
-		if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE) {
+		if (dump_bytes(dsp, dsp->dsa_drr,
+		    sizeof (dmu_replay_record_t)) != 0)
 			return (EINTR);
-		ba->pending_op = PENDING_NONE;
+		dsp->dsa_pending_op = PENDING_NONE;
 	}
 
 	/* write an OBJECT record */
-	bzero(ba->drr, sizeof (dmu_replay_record_t));
-	ba->drr->drr_type = DRR_OBJECT;
+	bzero(dsp->dsa_drr, sizeof (dmu_replay_record_t));
+	dsp->dsa_drr->drr_type = DRR_OBJECT;
 	drro->drr_object = object;
 	drro->drr_type = dnp->dn_type;
 	drro->drr_bonustype = dnp->dn_bonustype;
@@ -304,19 +294,19 @@ dump_dnode(struct backuparg *ba, uint64_t object, dnode_phys_t *dnp)
 	drro->drr_bonuslen = dnp->dn_bonuslen;
 	drro->drr_checksumtype = dnp->dn_checksum;
 	drro->drr_compress = dnp->dn_compress;
-	drro->drr_toguid = ba->toguid;
+	drro->drr_toguid = dsp->dsa_toguid;
 
-	if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dump_bytes(dsp, dsp->dsa_drr, sizeof (dmu_replay_record_t)) != 0)
 		return (EINTR);
 
-	if (dump_bytes(ba, DN_BONUS(dnp), P2ROUNDUP(dnp->dn_bonuslen, 8)) != 0)
+	if (dump_bytes(dsp, DN_BONUS(dnp), P2ROUNDUP(dnp->dn_bonuslen, 8)) != 0)
 		return (EINTR);
 
 	/* free anything past the end of the file */
-	if (dump_free(ba, object, (dnp->dn_maxblkid + 1) *
+	if (dump_free(dsp, object, (dnp->dn_maxblkid + 1) *
 	    (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT), -1ULL))
 		return (EINTR);
-	if (ba->err)
+	if (dsp->dsa_err)
 		return (EINTR);
 	return (0);
 }
@@ -330,7 +320,7 @@ static int
 backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
     const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
 {
-	struct backuparg *ba = arg;
+	dmu_sendarg_t *dsp = arg;
 	dmu_object_type_t type = bp ? BP_GET_TYPE(bp) : DMU_OT_NONE;
 	int err = 0;
 
@@ -343,10 +333,10 @@ backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
 	} else if (bp == NULL && zb->zb_object == DMU_META_DNODE_OBJECT) {
 		uint64_t span = BP_SPAN(dnp, zb->zb_level);
 		uint64_t dnobj = (zb->zb_blkid * span) >> DNODE_SHIFT;
-		err = dump_freeobjects(ba, dnobj, span >> DNODE_SHIFT);
+		err = dump_freeobjects(dsp, dnobj, span >> DNODE_SHIFT);
 	} else if (bp == NULL) {
 		uint64_t span = BP_SPAN(dnp, zb->zb_level);
-		err = dump_free(ba, zb->zb_object, zb->zb_blkid * span, span);
+		err = dump_free(dsp, zb->zb_object, zb->zb_blkid * span, span);
 	} else if (zb->zb_level > 0 || type == DMU_OT_OBJSET) {
 		return (0);
 	} else if (type == DMU_OT_DNODE) {
@@ -365,7 +355,7 @@ backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
 		for (i = 0; i < blksz >> DNODE_SHIFT; i++) {
 			uint64_t dnobj = (zb->zb_blkid <<
 			    (DNODE_BLOCK_SHIFT - DNODE_SHIFT)) + i;
-			err = dump_dnode(ba, dnobj, blk+i);
+			err = dump_dnode(dsp, dnobj, blk+i);
 			if (err)
 				break;
 		}
@@ -380,7 +370,7 @@ backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
 		    ZIO_FLAG_CANFAIL, &aflags, zb) != 0)
 			return (EIO);
 
-		err = dump_spill(ba, zb->zb_object, blksz, abuf->b_data);
+		err = dump_spill(dsp, zb->zb_object, blksz, abuf->b_data);
 		(void) arc_buf_remove_ref(abuf, &abuf);
 	} else { /* it's a level-0 block of a regular object */
 		uint32_t aflags = ARC_WAIT;
@@ -404,7 +394,7 @@ backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
 			}
 		}
 
-		err = dump_data(ba, type, zb->zb_object, zb->zb_blkid * blksz,
+		err = dump_data(dsp, type, zb->zb_object, zb->zb_blkid * blksz,
 		    blksz, bp, abuf->b_data);
 		(void) arc_buf_remove_ref(abuf, &abuf);
 	}
@@ -414,13 +404,13 @@ backup_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
 }
 
 int
-dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
-    struct file *fp, offset_t *off)
+dmu_send(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
+    int outfd, struct file *fp, offset_t *off)
 {
 	dsl_dataset_t *ds = tosnap->os_dsl_dataset;
 	dsl_dataset_t *fromds = fromsnap ? fromsnap->os_dsl_dataset : NULL;
 	dmu_replay_record_t *drr;
-	struct backuparg ba;
+	dmu_sendarg_t *dsp;
 	int err;
 	uint64_t fromtxg = 0;
 
@@ -461,8 +451,10 @@ dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
 #ifdef _KERNEL
 	if (dmu_objset_type(tosnap) == DMU_OST_ZFS) {
 		uint64_t version;
-		if (zfs_get_zplprop(tosnap, ZFS_PROP_VERSION, &version) != 0)
+		if (zfs_get_zplprop(tosnap, ZFS_PROP_VERSION, &version) != 0) {
+			kmem_free(drr, sizeof (dmu_replay_record_t));
 			return (EINVAL);
+		}
 		if (version == ZPL_VERSION_SA) {
 			DMU_SET_FEATUREFLAGS(
 			    drr->drr_u.drr_begin.drr_versioninfo,
@@ -489,47 +481,60 @@ dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
 	if (fromorigin)
 		dsl_dataset_rele(fromds, FTAG);
 
-	ba.drr = drr;
-	ba.td = curthread;
-	ba.fp = fp;
-	ba.os = tosnap;
-	ba.off = off;
-	ba.toguid = ds->ds_phys->ds_guid;
-	ZIO_SET_CHECKSUM(&ba.zc, 0, 0, 0, 0);
-	ba.pending_op = PENDING_NONE;
-
-	if (dump_bytes(&ba, drr, sizeof (dmu_replay_record_t)) != 0) {
-		kmem_free(drr, sizeof (dmu_replay_record_t));
-		return (ba.err);
+	dsp = kmem_zalloc(sizeof (dmu_sendarg_t), KM_SLEEP);
+
+	dsp->dsa_drr = drr;
+	dsp->dsa_outfd = outfd;
+	dsp->dsa_proc = curproc;
+	dsp->dsa_td = curthread;
+	dsp->dsa_fp = fp;
+	dsp->dsa_os = tosnap;
+	dsp->dsa_off = off;
+	dsp->dsa_toguid = ds->ds_phys->ds_guid;
+	ZIO_SET_CHECKSUM(&dsp->dsa_zc, 0, 0, 0, 0);
+	dsp->dsa_pending_op = PENDING_NONE;
+
+	mutex_enter(&ds->ds_sendstream_lock);
+	list_insert_head(&ds->ds_sendstreams, dsp);
+	mutex_exit(&ds->ds_sendstream_lock);
+
+	if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0) {
+		err = dsp->dsa_err;
+		goto out;
 	}
 
 	err = traverse_dataset(ds, fromtxg, TRAVERSE_PRE | TRAVERSE_PREFETCH,
-	    backup_cb, &ba);
+	    backup_cb, dsp);
 
-	if (ba.pending_op != PENDING_NONE)
-		if (dump_bytes(&ba, drr, sizeof (dmu_replay_record_t)) != 0)
+	if (dsp->dsa_pending_op != PENDING_NONE)
+		if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0)
 			err = EINTR;
 
 	if (err) {
-		if (err == EINTR && ba.err)
-			err = ba.err;
-		kmem_free(drr, sizeof (dmu_replay_record_t));
-		return (err);
+		if (err == EINTR && dsp->dsa_err)
+			err = dsp->dsa_err;
+		goto out;
 	}
 
 	bzero(drr, sizeof (dmu_replay_record_t));
 	drr->drr_type = DRR_END;
-	drr->drr_u.drr_end.drr_checksum = ba.zc;
-	drr->drr_u.drr_end.drr_toguid = ba.toguid;
+	drr->drr_u.drr_end.drr_checksum = dsp->dsa_zc;
+	drr->drr_u.drr_end.drr_toguid = dsp->dsa_toguid;
 
-	if (dump_bytes(&ba, drr, sizeof (dmu_replay_record_t)) != 0) {
-		kmem_free(drr, sizeof (dmu_replay_record_t));
-		return (ba.err);
+	if (dump_bytes(dsp, drr, sizeof (dmu_replay_record_t)) != 0) {
+		err = dsp->dsa_err;
+		goto out;
 	}
 
+out:
+	mutex_enter(&ds->ds_sendstream_lock);
+	list_remove(&ds->ds_sendstreams, dsp);
+	mutex_exit(&ds->ds_sendstream_lock);
+
 	kmem_free(drr, sizeof (dmu_replay_record_t));
+	kmem_free(dsp, sizeof (dmu_sendarg_t));
 
-	return (0);
+	return (err);
 }
 
 int
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
index ff49fa5..f28f83b 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c
@@ -21,6 +21,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  * Portions Copyright (c) 2011 Martin Matuska <mm@FreeBSD.org>
@@ -32,6 +33,7 @@
 #include <sys/dsl_prop.h>
 #include <sys/dsl_synctask.h>
 #include <sys/dmu_traverse.h>
+#include <sys/dmu_impl.h>
 #include <sys/dmu_tx.h>
 #include <sys/arc.h>
 #include <sys/zio.h>
@@ -401,6 +403,8 @@ dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 		mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
 		mutex_init(&ds->ds_recvlock, NULL, MUTEX_DEFAULT, NULL);
 		mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
+		mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
+
 		rw_init(&ds->ds_rwlock, 0, 0, 0);
 		cv_init(&ds->ds_exclusive_cv, NULL, CV_DEFAULT, NULL);
 
@@ -408,6 +412,9 @@ dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 		dsl_deadlist_open(&ds->ds_deadlist,
 		    mos, ds->ds_phys->ds_deadlist_obj);
 
+		list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
+		    offsetof(dmu_sendarg_t, dsa_link));
+
 		if (err == 0) {
 			err = dsl_dir_open_obj(dp,
 			    ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
index 585acf3..4d24f57 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
@@ -24,6 +24,7 @@
  */
 /*
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
 /* Portions Copyright 2010 Robert Milkowski */
@@ -706,8 +707,8 @@ typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
     dmu_traverse_cb_t cb, void *arg);
 
-int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
-    struct file *fp, offset_t *off);
+int dmu_send(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
+    int outfd, struct file *fp, offset_t *off);
 int dmu_send_estimate(objset_t *tosnap, objset_t *fromsnap,
     boolean_t fromorigin, uint64_t *sizep);
 
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_impl.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_impl.h
index 2cb7f12..e281121 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_impl.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_impl.h
@@ -21,6 +21,8 @@
 /*
  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
 #ifndef _SYS_DMU_IMPL_H
@@ -31,6 +33,7 @@
 #include <sys/dnode.h>
 #include <sys/kstat.h>
 #include <sys/zfs_context.h>
+#include <sys/zfs_ioctl.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -265,6 +268,33 @@ static xuio_stats_t xuio_stats = {
 	atomic_add_64(&xuio_stats.stat.value.ui64, (val))
 #define	XUIOSTAT_BUMP(stat)	XUIOSTAT_INCR(stat, 1)
 
+/*
+ * The list of data whose inclusion in a send stream can be pending from
+ * one call to backup_cb to another.  Multiple calls to dump_free() and
+ * dump_freeobjects() can be aggregated into a single DRR_FREE or
+ * DRR_FREEOBJECTS replay record.
+ */
+typedef enum {
+	PENDING_NONE,
+	PENDING_FREE,
+	PENDING_FREEOBJECTS
+} dmu_pendop_t;
+
+typedef struct dmu_sendarg {
+	list_node_t dsa_link;
+	dmu_replay_record_t *dsa_drr;
+	kthread_t *dsa_td;
+	struct file *dsa_fp;
+	int dsa_outfd;
+	struct proc *dsa_proc;
+	offset_t *dsa_off;
+	objset_t *dsa_os;
+	zio_cksum_t dsa_zc;
+	uint64_t dsa_toguid;
+	int dsa_err;
+	dmu_pendop_t dsa_pending_op;
+} dmu_sendarg_t;
+
 
 #ifdef	__cplusplus
 }
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
index 50b2e7b..56d2f6b 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h
@@ -23,6 +23,7 @@
  * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>.
  * All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
 #ifndef	_SYS_DSL_DATASET_H
@@ -152,6 +153,9 @@ typedef struct dsl_dataset {
 	uint64_t ds_reserved;	/* cached refreservation */
 	uint64_t ds_quota;	/* cached refquota */
 
+	kmutex_t ds_sendstream_lock;
+	list_t ds_sendstreams;
+
 	/* Protected by ds_lock; keep at end of struct for better locality */
 	char ds_snapname[MAXNAMELEN];
 } dsl_dataset_t;
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
index fe4c892..8f53ded 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c
@@ -25,6 +25,7 @@
  * Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org>
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  */
 
 #include <sys/types.h>
@@ -57,6 +58,7 @@
 #include <sys/dsl_prop.h>
 #include <sys/dsl_deleg.h>
 #include <sys/dmu_objset.h>
+#include <sys/dmu_impl.h>
 #include <sys/sunddi.h>
 #include <sys/policy.h>
 #include <sys/zone.h>
@@ -3933,7 +3935,8 @@ zfs_ioc_send(zfs_cmd_t *zc)
 		}
 
 		off = fp->f_offset;
-		error = dmu_sendbackup(tosnap, fromsnap, zc->zc_obj, fp, &off);
+		error = dmu_send(tosnap, fromsnap, zc->zc_obj,
+		    zc->zc_cookie, fp, &off);
 
 		if (off >= 0 && off <= MAXOFFSET_T)
 			fp->f_offset = off;
@@ -3945,6 +3948,49 @@ zfs_ioc_send(zfs_cmd_t *zc)
 	return (error);
 }
 
+/*
+ * inputs:
+ * zc_name	name of snapshot on which to report progress
+ * zc_cookie	file descriptor of send stream
+ *
+ * outputs:
+ * zc_cookie	number of bytes written in send stream thus far
+ */
+static int
+zfs_ioc_send_progress(zfs_cmd_t *zc)
+{
+	dsl_dataset_t *ds;
+	dmu_sendarg_t *dsp = NULL;
+	int error;
+
+	if ((error = dsl_dataset_hold(zc->zc_name, FTAG, &ds)) != 0)
+		return (error);
+
+	mutex_enter(&ds->ds_sendstream_lock);
+
+	/*
+	 * Iterate over all the send streams currently active on this dataset.
+	 * If there's one which matches the specified file descriptor _and_ the
+	 * stream was started by the current process, return the progress of
+	 * that stream.
+	 */
+	for (dsp = list_head(&ds->ds_sendstreams); dsp != NULL;
+	    dsp = list_next(&ds->ds_sendstreams, dsp)) {
+		if (dsp->dsa_outfd == zc->zc_cookie &&
+		    dsp->dsa_proc == curproc)
+			break;
+	}
+
+	if (dsp != NULL)
+		zc->zc_cookie = *(dsp->dsa_off);
+	else
+		error = ENOENT;
+
+	mutex_exit(&ds->ds_sendstream_lock);
+	dsl_dataset_rele(ds, FTAG);
+	return (error);
+}
+
 static int
 zfs_ioc_inject_fault(zfs_cmd_t *zc)
 {
@@ -4946,7 +4992,9 @@ static zfs_ioc_vec_t zfs_ioc_vec[] = {
 	{ zfs_ioc_space_written, zfs_secpolicy_read, DATASET_NAME, B_FALSE,
 	    B_TRUE },
 	{ zfs_ioc_space_snaps, zfs_secpolicy_read, DATASET_NAME, B_FALSE,
-	    B_TRUE }
+	    B_TRUE },
+	{ zfs_ioc_send_progress, zfs_secpolicy_read, DATASET_NAME, B_FALSE,
+	    B_FALSE }
 };
 
 int
diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
index 0729bff..ca98fca 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
@@ -23,6 +23,8 @@
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  */
 
 /* Portions Copyright 2010 Robert Milkowski */
@@ -794,6 +796,7 @@ typedef	unsigned long	zfs_ioc_t;
 #define	ZFS_IOC_POOL_REGUID		_IOWR('Z', 60, struct zfs_cmd)
 #define	ZFS_IOC_SPACE_WRITTEN		_IOWR('Z', 61, struct zfs_cmd)
 #define	ZFS_IOC_SPACE_SNAPS		_IOWR('Z', 62, struct zfs_cmd)
+#define	ZFS_IOC_SEND_PROGRESS		_IOWR('Z', 63, struct zfs_cmd)
 
 /*
  * Internal SPA load state.  Used by FMA diagnosis engine.