xref: /freebsd/sys/contrib/openzfs/module/zfs/ddt_zap.c (revision f5541f9f473430a3e608e07f623294322853d25a)
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 https://opensource.org/licenses/CDDL-1.0.
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/ddt_impl.h>
32 #include <sys/zap.h>
33 #include <sys/dmu_tx.h>
34 #include <sys/zio_compress.h>
35 
36 static unsigned int ddt_zap_default_bs = 15;
37 static unsigned int ddt_zap_default_ibs = 15;
38 
39 #define	DDT_ZAP_COMPRESS_BYTEORDER_MASK	0x80
40 #define	DDT_ZAP_COMPRESS_FUNCTION_MASK	0x7f
41 
42 #define	DDT_KEY_WORDS	(sizeof (ddt_key_t) / sizeof (uint64_t))
43 
44 static size_t
45 ddt_zap_compress(const void *src, uchar_t *dst, size_t s_len, size_t d_len)
46 {
47 	uchar_t *version = dst++;
48 	int cpfunc = ZIO_COMPRESS_ZLE;
49 	zio_compress_info_t *ci = &zio_compress_table[cpfunc];
50 	size_t c_len;
51 
52 	ASSERT3U(d_len, >=, s_len + 1);	/* no compression plus version byte */
53 
54 	c_len = ci->ci_compress((void *)src, dst, s_len, d_len - 1,
55 	    ci->ci_level);
56 
57 	if (c_len == s_len) {
58 		cpfunc = ZIO_COMPRESS_OFF;
59 		memcpy(dst, src, s_len);
60 	}
61 
62 	*version = cpfunc;
63 	if (ZFS_HOST_BYTEORDER)
64 		*version |= DDT_ZAP_COMPRESS_BYTEORDER_MASK;
65 
66 	return (c_len + 1);
67 }
68 
69 static void
70 ddt_zap_decompress(uchar_t *src, void *dst, size_t s_len, size_t d_len)
71 {
72 	uchar_t version = *src++;
73 	int cpfunc = version & DDT_ZAP_COMPRESS_FUNCTION_MASK;
74 	zio_compress_info_t *ci = &zio_compress_table[cpfunc];
75 
76 	if (ci->ci_decompress != NULL)
77 		(void) ci->ci_decompress(src, dst, s_len, d_len, ci->ci_level);
78 	else
79 		memcpy(dst, src, d_len);
80 
81 	if (((version & DDT_ZAP_COMPRESS_BYTEORDER_MASK) != 0) !=
82 	    (ZFS_HOST_BYTEORDER != 0))
83 		byteswap_uint64_array(dst, d_len);
84 }
85 
86 static int
87 ddt_zap_create(objset_t *os, uint64_t *objectp, dmu_tx_t *tx, boolean_t prehash)
88 {
89 	zap_flags_t flags = ZAP_FLAG_HASH64 | ZAP_FLAG_UINT64_KEY;
90 
91 	if (prehash)
92 		flags |= ZAP_FLAG_PRE_HASHED_KEY;
93 
94 	*objectp = zap_create_flags(os, 0, flags, DMU_OT_DDT_ZAP,
95 	    ddt_zap_default_bs, ddt_zap_default_ibs,
96 	    DMU_OT_NONE, 0, tx);
97 	if (*objectp == 0)
98 		return (SET_ERROR(ENOTSUP));
99 
100 	return (0);
101 }
102 
103 static int
104 ddt_zap_destroy(objset_t *os, uint64_t object, dmu_tx_t *tx)
105 {
106 	return (zap_destroy(os, object, tx));
107 }
108 
109 static int
110 ddt_zap_lookup(objset_t *os, uint64_t object,
111     const ddt_key_t *ddk, ddt_phys_t *phys, size_t psize)
112 {
113 	uchar_t *cbuf;
114 	uint64_t one, csize;
115 	int error;
116 
117 	error = zap_length_uint64(os, object, (uint64_t *)ddk,
118 	    DDT_KEY_WORDS, &one, &csize);
119 	if (error)
120 		return (error);
121 
122 	ASSERT3U(one, ==, 1);
123 	ASSERT3U(csize, <=, psize + 1);
124 
125 	cbuf = kmem_alloc(csize, KM_SLEEP);
126 
127 	error = zap_lookup_uint64(os, object, (uint64_t *)ddk,
128 	    DDT_KEY_WORDS, 1, csize, cbuf);
129 	if (error == 0)
130 		ddt_zap_decompress(cbuf, phys, csize, psize);
131 
132 	kmem_free(cbuf, csize);
133 
134 	return (error);
135 }
136 
137 static int
138 ddt_zap_contains(objset_t *os, uint64_t object, const ddt_key_t *ddk)
139 {
140 	return (zap_length_uint64(os, object, (uint64_t *)ddk, DDT_KEY_WORDS,
141 	    NULL, NULL));
142 }
143 
144 static void
145 ddt_zap_prefetch(objset_t *os, uint64_t object, const ddt_key_t *ddk)
146 {
147 	(void) zap_prefetch_uint64(os, object, (uint64_t *)ddk, DDT_KEY_WORDS);
148 }
149 
150 static void
151 ddt_zap_prefetch_all(objset_t *os, uint64_t object)
152 {
153 	(void) zap_prefetch_object(os, object);
154 }
155 
156 static int
157 ddt_zap_update(objset_t *os, uint64_t object, const ddt_key_t *ddk,
158     const ddt_phys_t *phys, size_t psize, dmu_tx_t *tx)
159 {
160 	const size_t cbuf_size = psize + 1;
161 
162 	uchar_t *cbuf = kmem_alloc(cbuf_size, KM_SLEEP);
163 
164 	uint64_t csize = ddt_zap_compress(phys, cbuf, psize, cbuf_size);
165 
166 	int error = zap_update_uint64(os, object, (uint64_t *)ddk,
167 	    DDT_KEY_WORDS, 1, csize, cbuf, tx);
168 
169 	kmem_free(cbuf, cbuf_size);
170 
171 	return (error);
172 }
173 
174 static int
175 ddt_zap_remove(objset_t *os, uint64_t object, const ddt_key_t *ddk,
176     dmu_tx_t *tx)
177 {
178 	return (zap_remove_uint64(os, object, (uint64_t *)ddk,
179 	    DDT_KEY_WORDS, tx));
180 }
181 
182 static int
183 ddt_zap_walk(objset_t *os, uint64_t object, uint64_t *walk, ddt_key_t *ddk,
184     ddt_phys_t *phys, size_t psize)
185 {
186 	zap_cursor_t zc;
187 	zap_attribute_t za;
188 	int error;
189 
190 	if (*walk == 0) {
191 		/*
192 		 * We don't want to prefetch the entire ZAP object, because
193 		 * it can be enormous.  Also the primary use of DDT iteration
194 		 * is for scrubbing, in which case we will be issuing many
195 		 * scrub I/Os for each ZAP block that we read in, so
196 		 * reading the ZAP is unlikely to be the bottleneck.
197 		 */
198 		zap_cursor_init_noprefetch(&zc, os, object);
199 	} else {
200 		zap_cursor_init_serialized(&zc, os, object, *walk);
201 	}
202 	if ((error = zap_cursor_retrieve(&zc, &za)) == 0) {
203 		uint64_t csize = za.za_num_integers;
204 
205 		ASSERT3U(za.za_integer_length, ==, 1);
206 		ASSERT3U(csize, <=, psize + 1);
207 
208 		uchar_t *cbuf = kmem_alloc(csize, KM_SLEEP);
209 
210 		error = zap_lookup_uint64(os, object, (uint64_t *)za.za_name,
211 		    DDT_KEY_WORDS, 1, csize, cbuf);
212 		ASSERT0(error);
213 		if (error == 0) {
214 			ddt_zap_decompress(cbuf, phys, csize, psize);
215 			*ddk = *(ddt_key_t *)za.za_name;
216 		}
217 
218 		kmem_free(cbuf, csize);
219 
220 		zap_cursor_advance(&zc);
221 		*walk = zap_cursor_serialize(&zc);
222 	}
223 	zap_cursor_fini(&zc);
224 	return (error);
225 }
226 
227 static int
228 ddt_zap_count(objset_t *os, uint64_t object, uint64_t *count)
229 {
230 	return (zap_count(os, object, count));
231 }
232 
233 const ddt_ops_t ddt_zap_ops = {
234 	"zap",
235 	ddt_zap_create,
236 	ddt_zap_destroy,
237 	ddt_zap_lookup,
238 	ddt_zap_contains,
239 	ddt_zap_prefetch,
240 	ddt_zap_prefetch_all,
241 	ddt_zap_update,
242 	ddt_zap_remove,
243 	ddt_zap_walk,
244 	ddt_zap_count,
245 };
246 
247 /* BEGIN CSTYLED */
248 ZFS_MODULE_PARAM(zfs_dedup, , ddt_zap_default_bs, UINT, ZMOD_RW,
249 	"DDT ZAP leaf blockshift");
250 ZFS_MODULE_PARAM(zfs_dedup, , ddt_zap_default_ibs, UINT, ZMOD_RW,
251 	"DDT ZAP indirect blockshift");
252 /* END CSTYLED */
253