xref: /titanic_41/usr/src/uts/common/fs/zfs/dmu_object.c (revision fae4f2456bc35aa98a910bed286d2eaea73556cf)
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 by Delphix. All rights reserved.
24  */
25 
26 #include <sys/dmu.h>
27 #include <sys/dmu_objset.h>
28 #include <sys/dmu_tx.h>
29 #include <sys/dnode.h>
30 #include <sys/zap.h>
31 #include <sys/zfeature.h>
32 
33 uint64_t
34 dmu_object_alloc(objset_t *os, dmu_object_type_t ot, int blocksize,
35     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
36 {
37 	uint64_t object;
38 	uint64_t L2_dnode_count = DNODES_PER_BLOCK <<
39 	    (DMU_META_DNODE(os)->dn_indblkshift - SPA_BLKPTRSHIFT);
40 	dnode_t *dn = NULL;
41 	int restarted = B_FALSE;
42 
43 	mutex_enter(&os->os_obj_lock);
44 	for (;;) {
45 		object = os->os_obj_next;
46 		/*
47 		 * Each time we polish off an L2 bp worth of dnodes
48 		 * (2^13 objects), move to another L2 bp that's still
49 		 * reasonably sparse (at most 1/4 full).  Look from the
50 		 * beginning once, but after that keep looking from here.
51 		 * If we can't find one, just keep going from here.
52 		 */
53 		if (P2PHASE(object, L2_dnode_count) == 0) {
54 			uint64_t offset = restarted ? object << DNODE_SHIFT : 0;
55 			int error = dnode_next_offset(DMU_META_DNODE(os),
56 			    DNODE_FIND_HOLE,
57 			    &offset, 2, DNODES_PER_BLOCK >> 2, 0);
58 			restarted = B_TRUE;
59 			if (error == 0)
60 				object = offset >> DNODE_SHIFT;
61 		}
62 		os->os_obj_next = ++object;
63 
64 		/*
65 		 * XXX We should check for an i/o error here and return
66 		 * up to our caller.  Actually we should pre-read it in
67 		 * dmu_tx_assign(), but there is currently no mechanism
68 		 * to do so.
69 		 */
70 		(void) dnode_hold_impl(os, object, DNODE_MUST_BE_FREE,
71 		    FTAG, &dn);
72 		if (dn)
73 			break;
74 
75 		if (dmu_object_next(os, &object, B_TRUE, 0) == 0)
76 			os->os_obj_next = object - 1;
77 	}
78 
79 	dnode_allocate(dn, ot, blocksize, 0, bonustype, bonuslen, tx);
80 	dnode_rele(dn, FTAG);
81 
82 	mutex_exit(&os->os_obj_lock);
83 
84 	dmu_tx_add_new_object(tx, os, object);
85 	return (object);
86 }
87 
88 int
89 dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
90     int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
91 {
92 	dnode_t *dn;
93 	int err;
94 
95 	if (object == DMU_META_DNODE_OBJECT && !dmu_tx_private_ok(tx))
96 		return (SET_ERROR(EBADF));
97 
98 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_FREE, FTAG, &dn);
99 	if (err)
100 		return (err);
101 	dnode_allocate(dn, ot, blocksize, 0, bonustype, bonuslen, tx);
102 	dnode_rele(dn, FTAG);
103 
104 	dmu_tx_add_new_object(tx, os, object);
105 	return (0);
106 }
107 
108 int
109 dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
110     int blocksize, dmu_object_type_t bonustype, int bonuslen)
111 {
112 	dnode_t *dn;
113 	dmu_tx_t *tx;
114 	int nblkptr;
115 	int err;
116 
117 	if (object == DMU_META_DNODE_OBJECT)
118 		return (SET_ERROR(EBADF));
119 
120 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
121 	    FTAG, &dn);
122 	if (err)
123 		return (err);
124 
125 	if (dn->dn_type == ot && dn->dn_datablksz == blocksize &&
126 	    dn->dn_bonustype == bonustype && dn->dn_bonuslen == bonuslen) {
127 		/* nothing is changing, this is a noop */
128 		dnode_rele(dn, FTAG);
129 		return (0);
130 	}
131 
132 	if (bonustype == DMU_OT_SA) {
133 		nblkptr = 1;
134 	} else {
135 		nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT);
136 	}
137 
138 	/*
139 	 * If we are losing blkptrs or changing the block size this must
140 	 * be a new file instance.   We must clear out the previous file
141 	 * contents before we can change this type of metadata in the dnode.
142 	 */
143 	if (dn->dn_nblkptr > nblkptr || dn->dn_datablksz != blocksize) {
144 		err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END);
145 		if (err)
146 			goto out;
147 	}
148 
149 	tx = dmu_tx_create(os);
150 	dmu_tx_hold_bonus(tx, object);
151 	err = dmu_tx_assign(tx, TXG_WAIT);
152 	if (err) {
153 		dmu_tx_abort(tx);
154 		goto out;
155 	}
156 
157 	dnode_reallocate(dn, ot, blocksize, bonustype, bonuslen, tx);
158 
159 	dmu_tx_commit(tx);
160 out:
161 	dnode_rele(dn, FTAG);
162 
163 	return (err);
164 }
165 
166 int
167 dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx)
168 {
169 	dnode_t *dn;
170 	int err;
171 
172 	ASSERT(object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx));
173 
174 	err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
175 	    FTAG, &dn);
176 	if (err)
177 		return (err);
178 
179 	ASSERT(dn->dn_type != DMU_OT_NONE);
180 	dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
181 	dnode_free(dn, tx);
182 	dnode_rele(dn, FTAG);
183 
184 	return (0);
185 }
186 
187 int
188 dmu_object_next(objset_t *os, uint64_t *objectp, boolean_t hole, uint64_t txg)
189 {
190 	uint64_t offset = (*objectp + 1) << DNODE_SHIFT;
191 	int error;
192 
193 	error = dnode_next_offset(DMU_META_DNODE(os),
194 	    (hole ? DNODE_FIND_HOLE : 0), &offset, 0, DNODES_PER_BLOCK, txg);
195 
196 	*objectp = offset >> DNODE_SHIFT;
197 
198 	return (error);
199 }
200 
201 /*
202  * Turn this object from old_type into DMU_OTN_ZAP_METADATA, and bump the
203  * refcount on SPA_FEATURE_EXTENSIBLE_DATASET.
204  *
205  * Only for use from syncing context, on MOS objects.
206  */
207 void
208 dmu_object_zapify(objset_t *mos, uint64_t object, dmu_object_type_t old_type,
209     dmu_tx_t *tx)
210 {
211 	dnode_t *dn;
212 
213 	ASSERT(dmu_tx_is_syncing(tx));
214 
215 	VERIFY0(dnode_hold(mos, object, FTAG, &dn));
216 	if (dn->dn_type == DMU_OTN_ZAP_METADATA) {
217 		dnode_rele(dn, FTAG);
218 		return;
219 	}
220 	ASSERT3U(dn->dn_type, ==, old_type);
221 	ASSERT0(dn->dn_maxblkid);
222 	dn->dn_next_type[tx->tx_txg & TXG_MASK] = dn->dn_type =
223 	    DMU_OTN_ZAP_METADATA;
224 	dnode_setdirty(dn, tx);
225 	dnode_rele(dn, FTAG);
226 
227 	mzap_create_impl(mos, object, 0, 0, tx);
228 
229 	spa_feature_incr(dmu_objset_spa(mos),
230 	    SPA_FEATURE_EXTENSIBLE_DATASET, tx);
231 }
232 
233 void
234 dmu_object_free_zapified(objset_t *mos, uint64_t object, dmu_tx_t *tx)
235 {
236 	dnode_t *dn;
237 	dmu_object_type_t t;
238 
239 	ASSERT(dmu_tx_is_syncing(tx));
240 
241 	VERIFY0(dnode_hold(mos, object, FTAG, &dn));
242 	t = dn->dn_type;
243 	dnode_rele(dn, FTAG);
244 
245 	if (t == DMU_OTN_ZAP_METADATA) {
246 		spa_feature_decr(dmu_objset_spa(mos),
247 		    SPA_FEATURE_EXTENSIBLE_DATASET, tx);
248 	}
249 	VERIFY0(dmu_object_free(mos, object, tx));
250 }
251