Merge recent vendor changes:

3100 zvol rename fails with EBUSY when dirty
3104 eliminate empty bpobjs
3120 zinject hangs in zfsdev_ioctl() due to uninitialized zc

References:
  https://www.illumos.org/issues/3100
  https://www.illumos.org/issues/3104
  https://www.illumos.org/issues/3120

Obtained from:	illumos (vendor/illumos, vendor/illumos-sys)
MFC after:	2 weeks

1 files changed, 45 insertions, 9 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c
index dd6db21..4f39c39 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #include <sys/dsl_dataset.h>
@@ -163,12 +163,49 @@ dsl_deadlist_free(objset_t *os, uint64_t dlobj, dmu_tx_t *tx)
 
 	for (zap_cursor_init(&zc, os, dlobj);
 	    zap_cursor_retrieve(&zc, &za) == 0;
-	    zap_cursor_advance(&zc))
-		bpobj_free(os, za.za_first_integer, tx);
+	    zap_cursor_advance(&zc)) {
+		uint64_t obj = za.za_first_integer;
+		if (obj == dmu_objset_pool(os)->dp_empty_bpobj)
+			bpobj_decr_empty(os, tx);
+		else
+			bpobj_free(os, obj, tx);
+	}
 	zap_cursor_fini(&zc);
 	VERIFY3U(0, ==, dmu_object_free(os, dlobj, tx));
 }
 
+static void
+dle_enqueue(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
+    const blkptr_t *bp, dmu_tx_t *tx)
+{
+	if (dle->dle_bpobj.bpo_object ==
+	    dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
+		uint64_t obj = bpobj_alloc(dl->dl_os, SPA_MAXBLOCKSIZE, tx);
+		bpobj_close(&dle->dle_bpobj);
+		bpobj_decr_empty(dl->dl_os, tx);
+		VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
+		VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
+		    dle->dle_mintxg, obj, tx));
+	}
+	bpobj_enqueue(&dle->dle_bpobj, bp, tx);
+}
+
+static void
+dle_enqueue_subobj(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
+    uint64_t obj, dmu_tx_t *tx)
+{
+	if (dle->dle_bpobj.bpo_object !=
+	    dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
+		bpobj_enqueue_subobj(&dle->dle_bpobj, obj, tx);
+	} else {
+		bpobj_close(&dle->dle_bpobj);
+		bpobj_decr_empty(dl->dl_os, tx);
+		VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
+		VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
+		    dle->dle_mintxg, obj, tx));
+	}
+}
+
 void
 dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp, dmu_tx_t *tx)
 {
@@ -197,7 +234,7 @@ dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp, dmu_tx_t *tx)
 		dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
 	else
 		dle = AVL_PREV(&dl->dl_tree, dle);
-	bpobj_enqueue(&dle->dle_bpobj, bp, tx);
+	dle_enqueue(dl, dle, bp, tx);
 }
 
 /*
@@ -217,7 +254,7 @@ dsl_deadlist_add_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 
 	dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
 	dle->dle_mintxg = mintxg;
-	obj = bpobj_alloc(dl->dl_os, SPA_MAXBLOCKSIZE, tx);
+	obj = bpobj_alloc_empty(dl->dl_os, SPA_MAXBLOCKSIZE, tx);
 	VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 	avl_add(&dl->dl_tree, dle);
 
@@ -243,8 +280,7 @@ dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 	dle = avl_find(&dl->dl_tree, &dle_tofind, NULL);
 	dle_prev = AVL_PREV(&dl->dl_tree, dle);
 
-	bpobj_enqueue_subobj(&dle_prev->dle_bpobj,
-	    dle->dle_bpobj.bpo_object, tx);
+	dle_enqueue_subobj(dl, dle_prev, dle->dle_bpobj.bpo_object, tx);
 
 	avl_remove(&dl->dl_tree, dle);
 	bpobj_close(&dle->dle_bpobj);
@@ -302,7 +338,7 @@ dsl_deadlist_clone(dsl_deadlist_t *dl, uint64_t maxtxg,
 		if (dle->dle_mintxg >= maxtxg)
 			break;
 
-		obj = bpobj_alloc(dl->dl_os, SPA_MAXBLOCKSIZE, tx);
+		obj = bpobj_alloc_empty(dl->dl_os, SPA_MAXBLOCKSIZE, tx);
 		VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, newobj,
 		    dle->dle_mintxg, obj, tx));
 	}
@@ -400,7 +436,7 @@ dsl_deadlist_insert_bpobj(dsl_deadlist_t *dl, uint64_t obj, uint64_t birth,
 	dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 	if (dle == NULL)
 		dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
-	bpobj_enqueue_subobj(&dle->dle_bpobj, obj, tx);
+	dle_enqueue_subobj(dl, dle, obj, tx);
 }
 
 static int