xref: /illumos-gate/usr/src/uts/common/fs/zfs/dmu_object.c (revision 45818ee124adeaaf947698996b4f4c722afc6d1f)
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 (c) 2013, 2014 by Delphix. All rights reserved.
24  * Copyright 2014 HybridCluster. All rights reserved.
25  */
26 
27 #include <sys/dmu.h>
28 #include <sys/dmu_objset.h>
29 #include <sys/dmu_tx.h>
30 #include <sys/dnode.h>
31 #include <sys/zap.h>
32 #include <sys/zfeature.h>
33 
34 uint64_t
35 dmu_object_alloc(objset_t *os, dmu_object_type_t ot, int blocksize,
36     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
37 {
38 	uint64_t object;
39 	uint64_t L2_dnode_count = DNODES_PER_BLOCK <<
40 	    (DMU_META_DNODE(os)->dn_indblkshift - SPA_BLKPTRSHIFT);
41 	dnode_t *dn = NULL;
42 	int restarted = B_FALSE;
43 
44 	mutex_enter(&os->os_obj_lock);
45 	for (;;) {
46 		object = os->os_obj_next;
47 		/*
48 		 * Each time we polish off an L2 bp worth of dnodes
49 		 * (2^13 objects), move to another L2 bp that's still
50 		 * reasonably sparse (at most 1/4 full).  Look from the
51 		 * beginning once, but after that keep looking from here.
52 		 * If we can't find one, just keep going from here.
53 		 */
54 		if (P2PHASE(object, L2_dnode_count) == 0) {
55 			uint64_t offset = restarted ? object << DNODE_SHIFT : 0;
56 			int error = dnode_next_offset(DMU_META_DNODE(os),
57 			    DNODE_FIND_HOLE,
58 			    &offset, 2, DNODES_PER_BLOCK >> 2, 0);
59 			restarted = B_TRUE;
60 			if (error == 0)
61 				object = offset >> DNODE_SHIFT;
62 		}
63 		os->os_obj_next = ++object;
64 
65 		/*
66 		 * XXX We should check for an i/o error here and return
67 		 * up to our caller.  Actually we should pre-read it in
68 		 * dmu_tx_assign(), but there is currently no mechanism
69 		 * to do so.
70 		 */
71 		(void) dnode_hold_impl(os, object, DNODE_MUST_BE_FREE,
72 		    FTAG, &dn);
73 		if (dn)
74 			break;
75 
76 		if (dmu_object_next(os, &object, B_TRUE, 0) == 0)
77 			os->os_obj_next = object - 1;
78 	}
79 
80 	dnode_allocate(dn, ot, blocksize, 0, bonustype, bonuslen, tx);
81 	dnode_rele(dn, FTAG);
82 
83 	mutex_exit(&os->os_obj_lock);
84 
85 	dmu_tx_add_new_object(tx, os, object);
86 	return (object);
87 }
88 
89 int
90 dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
91     int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
92 {
93 	dnode_t *dn;
94 	int err;
95 
96 	if (object == DMU_META_DNODE_OBJECT && !dmu_tx_private_ok(tx))
97 		return (SET_ERROR(EBADF));
98 
99 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_FREE, FTAG, &dn);
100 	if (err)
101 		return (err);
102 	dnode_allocate(dn, ot, blocksize, 0, bonustype, bonuslen, tx);
103 	dnode_rele(dn, FTAG);
104 
105 	dmu_tx_add_new_object(tx, os, object);
106 	return (0);
107 }
108 
109 int
110 dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
111     int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
112 {
113 	dnode_t *dn;
114 	int err;
115 
116 	if (object == DMU_META_DNODE_OBJECT)
117 		return (SET_ERROR(EBADF));
118 
119 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
120 	    FTAG, &dn);
121 	if (err)
122 		return (err);
123 
124 	dnode_reallocate(dn, ot, blocksize, bonustype, bonuslen, tx);
125 
126 	dnode_rele(dn, FTAG);
127 	return (err);
128 }
129 
130 int
131 dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx)
132 {
133 	dnode_t *dn;
134 	int err;
135 
136 	ASSERT(object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx));
137 
138 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
139 	    FTAG, &dn);
140 	if (err)
141 		return (err);
142 
143 	ASSERT(dn->dn_type != DMU_OT_NONE);
144 	dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
145 	dnode_free(dn, tx);
146 	dnode_rele(dn, FTAG);
147 
148 	return (0);
149 }
150 
151 /*
152  * Return (in *objectp) the next object which is allocated (or a hole)
153  * after *object, taking into account only objects that may have been modified
154  * after the specified txg.
155  */
156 int
157 dmu_object_next(objset_t *os, uint64_t *objectp, boolean_t hole, uint64_t txg)
158 {
159 	uint64_t offset = (*objectp + 1) << DNODE_SHIFT;
160 	int error;
161 
162 	error = dnode_next_offset(DMU_META_DNODE(os),
163 	    (hole ? DNODE_FIND_HOLE : 0), &offset, 0, DNODES_PER_BLOCK, txg);
164 
165 	*objectp = offset >> DNODE_SHIFT;
166 
167 	return (error);
168 }
169 
170 /*
171  * Turn this object from old_type into DMU_OTN_ZAP_METADATA, and bump the
172  * refcount on SPA_FEATURE_EXTENSIBLE_DATASET.
173  *
174  * Only for use from syncing context, on MOS objects.
175  */
176 void
177 dmu_object_zapify(objset_t *mos, uint64_t object, dmu_object_type_t old_type,
178     dmu_tx_t *tx)
179 {
180 	dnode_t *dn;
181 
182 	ASSERT(dmu_tx_is_syncing(tx));
183 
184 	VERIFY0(dnode_hold(mos, object, FTAG, &dn));
185 	if (dn->dn_type == DMU_OTN_ZAP_METADATA) {
186 		dnode_rele(dn, FTAG);
187 		return;
188 	}
189 	ASSERT3U(dn->dn_type, ==, old_type);
190 	ASSERT0(dn->dn_maxblkid);
191 	dn->dn_next_type[tx->tx_txg & TXG_MASK] = dn->dn_type =
192 	    DMU_OTN_ZAP_METADATA;
193 	dnode_setdirty(dn, tx);
194 	dnode_rele(dn, FTAG);
195 
196 	mzap_create_impl(mos, object, 0, 0, tx);
197 
198 	spa_feature_incr(dmu_objset_spa(mos),
199 	    SPA_FEATURE_EXTENSIBLE_DATASET, tx);
200 }
201 
202 void
203 dmu_object_free_zapified(objset_t *mos, uint64_t object, dmu_tx_t *tx)
204 {
205 	dnode_t *dn;
206 	dmu_object_type_t t;
207 
208 	ASSERT(dmu_tx_is_syncing(tx));
209 
210 	VERIFY0(dnode_hold(mos, object, FTAG, &dn));
211 	t = dn->dn_type;
212 	dnode_rele(dn, FTAG);
213 
214 	if (t == DMU_OTN_ZAP_METADATA) {
215 		spa_feature_decr(dmu_objset_spa(mos),
216 		    SPA_FEATURE_EXTENSIBLE_DATASET, tx);
217 	}
218 	VERIFY0(dmu_object_free(mos, object, tx));
219 }
220