MFV r296515: 6536 zfs send: want a way to disable setting of

DRR_FLAG_FREERECORDS

Reviewed by: Anil Vijarnia <avijarnia@racktopsystems.com>
Reviewed by: Kim Shrier <kshrier@racktopsystems.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Andrew Stormont <astormont@racktopsystems.com>

illumos/illumos-gate@880094b

Author: amotin

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c

@@ -25,6 +25,7 @@
  * Copyright (c) 2014, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
  * Copyright 2014 HybridCluster. All rights reserved.
+ * Copyright 2016 RackTop Systems.
  */
 
 #include <sys/dmu.h>
@@ -64,6 +65,12 @@
 int zfs_send_corrupt_data = B_FALSE;
 int zfs_send_queue_length = 16 * 1024 * 1024;
 int zfs_recv_queue_length = 16 * 1024 * 1024;
+/* Set this tunable to FALSE to disable setting of DRR_FLAG_FREERECORDS */
+int zfs_send_set_freerecords_bit = B_TRUE;
+
+#ifdef _KERNEL
+TUNABLE_INT("vfs.zfs.send_set_freerecords_bit", &zfs_send_set_freerecords_bit);
+#endif
 
 static char *dmu_recv_tag = "dmu_recv_tag";
 const char *recv_clone_name = "%recv";
@@ -771,7 +778,8 @@ dmu_send_impl(void *tag, dsl_pool_t *dp, dsl_dataset_t *to_ds,
 	drr->drr_u.drr_begin.drr_toguid = dsl_dataset_phys(to_ds)->ds_guid;
 	if (dsl_dataset_phys(to_ds)->ds_flags & DS_FLAG_CI_DATASET)
 		drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CI_DATA;
-	drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_FREERECORDS;
+	if (zfs_send_set_freerecords_bit)
+		drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_FREERECORDS;
 
 	if (ancestor_zb != NULL) {
 		drr->drr_u.drr_begin.drr_fromguid =

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_ioctl.h

@@ -21,6 +21,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
+ * Copyright 2016 RackTop Systems.
  */
 
 #ifndef	_SYS_ZFS_IOCTL_H
@@ -124,6 +125,10 @@ typedef enum dmu_send_resume_token_version {
 
 #define	DMU_BACKUP_MAGIC 0x2F5bacbacULL
 
+/*
+ * Send stream flags.  Bits 24-31 are reserved for vendor-specific
+ * implementations and should not be used.
+ */
 #define	DRR_FLAG_CLONE		(1<<0)
 #define	DRR_FLAG_CI_DATA	(1<<1)
 /*