1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2022 The FreeBSD Foundation
5 *
6 * This software was developed by Mark Johnston under sponsorship from
7 * the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are
11 * met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <assert.h>
32 #include <stdlib.h>
33 #include <string.h>
34
35 #include <util.h>
36
37 #include "zfs.h"
38
39 #define DNODES_PER_CHUNK (MAXBLOCKSIZE / sizeof(dnode_phys_t))
40
41 struct objset_dnode_chunk {
42 dnode_phys_t buf[DNODES_PER_CHUNK];
43 unsigned int nextfree;
44 STAILQ_ENTRY(objset_dnode_chunk) next;
45 };
46
47 typedef struct zfs_objset {
48 /* Physical object set. */
49 objset_phys_t *phys;
50 off_t osloc;
51 off_t osblksz;
52 blkptr_t osbp; /* set in objset_write() */
53
54 /* Accounting. */
55 off_t space; /* bytes allocated to this objset */
56
57 /* dnode allocator. */
58 uint64_t dnodecount;
59 STAILQ_HEAD(, objset_dnode_chunk) dnodechunks;
60 } zfs_objset_t;
61
62 static void
dnode_init(dnode_phys_t * dnode,uint8_t type,uint8_t bonustype,uint16_t bonuslen)63 dnode_init(dnode_phys_t *dnode, uint8_t type, uint8_t bonustype,
64 uint16_t bonuslen)
65 {
66 dnode->dn_indblkshift = MAXBLOCKSHIFT;
67 dnode->dn_type = type;
68 dnode->dn_bonustype = bonustype;
69 dnode->dn_bonuslen = bonuslen;
70 dnode->dn_checksum = ZIO_CHECKSUM_FLETCHER_4;
71 dnode->dn_nlevels = 1;
72 dnode->dn_nblkptr = 1;
73 dnode->dn_flags = DNODE_FLAG_USED_BYTES;
74 }
75
76 zfs_objset_t *
objset_alloc(zfs_opt_t * zfs,uint64_t type)77 objset_alloc(zfs_opt_t *zfs, uint64_t type)
78 {
79 struct objset_dnode_chunk *chunk;
80 zfs_objset_t *os;
81
82 os = ecalloc(1, sizeof(*os));
83 os->osblksz = sizeof(objset_phys_t);
84 os->osloc = objset_space_alloc(zfs, os, &os->osblksz);
85
86 /*
87 * Object ID zero is always reserved for the meta dnode, which is
88 * embedded in the objset itself.
89 */
90 STAILQ_INIT(&os->dnodechunks);
91 chunk = ecalloc(1, sizeof(*chunk));
92 chunk->nextfree = 1;
93 STAILQ_INSERT_HEAD(&os->dnodechunks, chunk, next);
94 os->dnodecount = 1;
95
96 os->phys = ecalloc(1, os->osblksz);
97 os->phys->os_type = type;
98
99 dnode_init(&os->phys->os_meta_dnode, DMU_OT_DNODE, DMU_OT_NONE, 0);
100 os->phys->os_meta_dnode.dn_datablkszsec =
101 DNODE_BLOCK_SIZE >> MINBLOCKSHIFT;
102
103 return (os);
104 }
105
106 /*
107 * Write the dnode array and physical object set to disk.
108 */
109 static void
_objset_write(zfs_opt_t * zfs,zfs_objset_t * os,struct dnode_cursor * c,off_t loc)110 _objset_write(zfs_opt_t *zfs, zfs_objset_t *os, struct dnode_cursor *c,
111 off_t loc)
112 {
113 struct objset_dnode_chunk *chunk, *tmp;
114 unsigned int total;
115
116 /*
117 * Write out the dnode array, i.e., the meta-dnode. For some reason its
118 * data blocks must be 16KB in size no matter how large the array is.
119 */
120 total = 0;
121 STAILQ_FOREACH_SAFE(chunk, &os->dnodechunks, next, tmp) {
122 unsigned int i;
123
124 assert(chunk->nextfree > 0);
125 assert(chunk->nextfree <= os->dnodecount);
126 assert(chunk->nextfree <= DNODES_PER_CHUNK);
127
128 for (i = 0; i < chunk->nextfree; i += DNODES_PER_BLOCK) {
129 blkptr_t *bp;
130 uint64_t fill;
131
132 if (chunk->nextfree - i < DNODES_PER_BLOCK)
133 fill = DNODES_PER_BLOCK - (chunk->nextfree - i);
134 else
135 fill = 0;
136 bp = dnode_cursor_next(zfs, c,
137 (total + i) * sizeof(dnode_phys_t));
138 vdev_pwrite_dnode_indir(zfs, &os->phys->os_meta_dnode,
139 0, fill, chunk->buf + i, DNODE_BLOCK_SIZE, loc, bp);
140 loc += DNODE_BLOCK_SIZE;
141 }
142 total += i;
143
144 free(chunk);
145 }
146 dnode_cursor_finish(zfs, c);
147 STAILQ_INIT(&os->dnodechunks);
148
149 /*
150 * Write the object set itself. The saved block pointer will be copied
151 * into the referencing DSL dataset or the uberblocks.
152 */
153 vdev_pwrite_data(zfs, DMU_OT_OBJSET, ZIO_CHECKSUM_FLETCHER_4, 0,
154 os->dnodecount - 1, os->phys, os->osblksz, os->osloc, &os->osbp);
155 }
156
157 void
objset_write(zfs_opt_t * zfs,zfs_objset_t * os)158 objset_write(zfs_opt_t *zfs, zfs_objset_t *os)
159 {
160 struct dnode_cursor *c;
161 off_t dnodeloc, dnodesz;
162 uint64_t dnodecount;
163
164 /*
165 * There is a chicken-and-egg problem here when writing the MOS: we
166 * cannot write space maps before we're finished allocating space from
167 * the vdev, and we can't write the MOS without having allocated space
168 * for indirect dnode blocks. Thus, rather than lazily allocating
169 * indirect blocks for the meta-dnode (which would be simpler), they are
170 * allocated up-front and before writing space maps.
171 */
172 dnodecount = os->dnodecount;
173 if (os == zfs->mos)
174 dnodecount += zfs->mscount;
175 dnodesz = dnodecount * sizeof(dnode_phys_t);
176 c = dnode_cursor_init(zfs, os, &os->phys->os_meta_dnode, dnodesz,
177 DNODE_BLOCK_SIZE);
178 dnodesz = roundup2(dnodesz, DNODE_BLOCK_SIZE);
179 dnodeloc = objset_space_alloc(zfs, os, &dnodesz);
180
181 if (os == zfs->mos) {
182 vdev_spacemap_write(zfs);
183
184 /*
185 * We've finished allocating space, account for it in $MOS and
186 * in the parent directory.
187 */
188 dsl_dir_root_finalize(zfs, os->space);
189 }
190 _objset_write(zfs, os, c, dnodeloc);
191 }
192
193 dnode_phys_t *
objset_dnode_bonus_alloc(zfs_objset_t * os,uint8_t type,uint8_t bonustype,uint16_t bonuslen,uint64_t * idp)194 objset_dnode_bonus_alloc(zfs_objset_t *os, uint8_t type, uint8_t bonustype,
195 uint16_t bonuslen, uint64_t *idp)
196 {
197 struct objset_dnode_chunk *chunk;
198 dnode_phys_t *dnode;
199
200 assert(bonuslen <= DN_OLD_MAX_BONUSLEN);
201 assert(!STAILQ_EMPTY(&os->dnodechunks));
202
203 chunk = STAILQ_LAST(&os->dnodechunks, objset_dnode_chunk, next);
204 if (chunk->nextfree == DNODES_PER_CHUNK) {
205 chunk = ecalloc(1, sizeof(*chunk));
206 STAILQ_INSERT_TAIL(&os->dnodechunks, chunk, next);
207 }
208 *idp = os->dnodecount++;
209 dnode = &chunk->buf[chunk->nextfree++];
210 dnode_init(dnode, type, bonustype, bonuslen);
211 dnode->dn_datablkszsec = os->osblksz >> MINBLOCKSHIFT;
212 return (dnode);
213 }
214
215 dnode_phys_t *
objset_dnode_alloc(zfs_objset_t * os,uint8_t type,uint64_t * idp)216 objset_dnode_alloc(zfs_objset_t *os, uint8_t type, uint64_t *idp)
217 {
218 return (objset_dnode_bonus_alloc(os, type, DMU_OT_NONE, 0, idp));
219 }
220
221 /*
222 * Look up a physical dnode by ID. This is not used often so a linear search is
223 * fine.
224 */
225 dnode_phys_t *
objset_dnode_lookup(zfs_objset_t * os,uint64_t id)226 objset_dnode_lookup(zfs_objset_t *os, uint64_t id)
227 {
228 struct objset_dnode_chunk *chunk;
229
230 assert(id > 0);
231 assert(id < os->dnodecount);
232
233 STAILQ_FOREACH(chunk, &os->dnodechunks, next) {
234 if (id < DNODES_PER_CHUNK)
235 return (&chunk->buf[id]);
236 id -= DNODES_PER_CHUNK;
237 }
238 assert(0);
239 return (NULL);
240 }
241
242 off_t
objset_space_alloc(zfs_opt_t * zfs,zfs_objset_t * os,off_t * lenp)243 objset_space_alloc(zfs_opt_t *zfs, zfs_objset_t *os, off_t *lenp)
244 {
245 off_t loc;
246
247 loc = vdev_space_alloc(zfs, lenp);
248 os->space += *lenp;
249 return (loc);
250 }
251
252 uint64_t
objset_space(const zfs_objset_t * os)253 objset_space(const zfs_objset_t *os)
254 {
255 return (os->space);
256 }
257
258 void
objset_root_blkptr_copy(const zfs_objset_t * os,blkptr_t * bp)259 objset_root_blkptr_copy(const zfs_objset_t *os, blkptr_t *bp)
260 {
261 memcpy(bp, &os->osbp, sizeof(blkptr_t));
262 }
263