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/*
23 * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2018 by Delphix. All rights reserved.
25 */
26
27#include <sys/zfs_context.h>
28#include <sys/spa.h>
29#include <sys/zio.h>
30#include <sys/ddt.h>
31#include <sys/zap.h>
32#include <sys/dmu_tx.h>
33#include <util/sscanf.h>
34
35int ddt_zap_leaf_blockshift = 12;
36int ddt_zap_indirect_blockshift = 12;
37
38static int
39ddt_zap_create(objset_t *os, uint64_t *objectp, dmu_tx_t *tx, boolean_t prehash)
40{
41	zap_flags_t flags = ZAP_FLAG_HASH64 | ZAP_FLAG_UINT64_KEY;
42
43	if (prehash)
44		flags |= ZAP_FLAG_PRE_HASHED_KEY;
45
46	*objectp = zap_create_flags(os, 0, flags, DMU_OT_DDT_ZAP,
47	    ddt_zap_leaf_blockshift, ddt_zap_indirect_blockshift,
48	    DMU_OT_NONE, 0, tx);
49
50	return (*objectp == 0 ? ENOTSUP : 0);
51}
52
53static int
54ddt_zap_destroy(objset_t *os, uint64_t object, dmu_tx_t *tx)
55{
56	return (zap_destroy(os, object, tx));
57}
58
59static int
60ddt_zap_lookup(objset_t *os, uint64_t object, ddt_entry_t *dde)
61{
62	uchar_t cbuf[sizeof (dde->dde_phys) + 1];
63	uint64_t one, csize;
64	int error;
65
66	error = zap_length_uint64(os, object, (uint64_t *)&dde->dde_key,
67	    DDT_KEY_WORDS, &one, &csize);
68	if (error)
69		return (error);
70
71	ASSERT(one == 1);
72	ASSERT(csize <= sizeof (cbuf));
73
74	error = zap_lookup_uint64(os, object, (uint64_t *)&dde->dde_key,
75	    DDT_KEY_WORDS, 1, csize, cbuf);
76	if (error)
77		return (error);
78
79	ddt_decompress(cbuf, dde->dde_phys, csize, sizeof (dde->dde_phys));
80
81	return (0);
82}
83
84static void
85ddt_zap_prefetch(objset_t *os, uint64_t object, ddt_entry_t *dde)
86{
87	(void) zap_prefetch_uint64(os, object, (uint64_t *)&dde->dde_key,
88	    DDT_KEY_WORDS);
89}
90
91static int
92ddt_zap_update(objset_t *os, uint64_t object, ddt_entry_t *dde, dmu_tx_t *tx)
93{
94	uchar_t cbuf[sizeof (dde->dde_phys) + 1];
95	uint64_t csize;
96
97	csize = ddt_compress(dde->dde_phys, cbuf,
98	    sizeof (dde->dde_phys), sizeof (cbuf));
99
100	return (zap_update_uint64(os, object, (uint64_t *)&dde->dde_key,
101	    DDT_KEY_WORDS, 1, csize, cbuf, tx));
102}
103
104static int
105ddt_zap_remove(objset_t *os, uint64_t object, ddt_entry_t *dde, dmu_tx_t *tx)
106{
107	return (zap_remove_uint64(os, object, (uint64_t *)&dde->dde_key,
108	    DDT_KEY_WORDS, tx));
109}
110
111static int
112ddt_zap_walk(objset_t *os, uint64_t object, ddt_entry_t *dde, uint64_t *walk)
113{
114	zap_cursor_t zc;
115	zap_attribute_t za;
116	int error;
117
118	if (*walk == 0) {
119		/*
120		 * We don't want to prefetch the entire ZAP object, because
121		 * it can be enormous.  Also the primary use of DDT iteration
122		 * is for scrubbing, in which case we will be issuing many
123		 * scrub i/os for each ZAP block that we read in, so
124		 * reading the ZAP is unlikely to be the bottleneck.
125		 */
126		zap_cursor_init_noprefetch(&zc, os, object);
127	} else {
128		zap_cursor_init_serialized(&zc, os, object, *walk);
129	}
130	if ((error = zap_cursor_retrieve(&zc, &za)) == 0) {
131		uchar_t cbuf[sizeof (dde->dde_phys) + 1];
132		uint64_t csize = za.za_num_integers;
133		ASSERT(za.za_integer_length == 1);
134		error = zap_lookup_uint64(os, object, (uint64_t *)za.za_name,
135		    DDT_KEY_WORDS, 1, csize, cbuf);
136		ASSERT(error == 0);
137		if (error == 0) {
138			ddt_decompress(cbuf, dde->dde_phys, csize,
139			    sizeof (dde->dde_phys));
140			dde->dde_key = *(ddt_key_t *)za.za_name;
141		}
142		zap_cursor_advance(&zc);
143		*walk = zap_cursor_serialize(&zc);
144	}
145	zap_cursor_fini(&zc);
146	return (error);
147}
148
149static uint64_t
150ddt_zap_count(objset_t *os, uint64_t object)
151{
152	uint64_t count = 0;
153
154	VERIFY(zap_count(os, object, &count) == 0);
155
156	return (count);
157}
158
159const ddt_ops_t ddt_zap_ops = {
160	"zap",
161	ddt_zap_create,
162	ddt_zap_destroy,
163	ddt_zap_lookup,
164	ddt_zap_prefetch,
165	ddt_zap_update,
166	ddt_zap_remove,
167	ddt_zap_walk,
168	ddt_zap_count,
169};
170