xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/zap_impl.h (revision b24ab676)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_ZAP_IMPL_H
27 #define	_SYS_ZAP_IMPL_H
28 
29 #include <sys/zap.h>
30 #include <sys/zfs_context.h>
31 #include <sys/avl.h>
32 
33 #ifdef	__cplusplus
34 extern "C" {
35 #endif
36 
37 extern int fzap_default_block_shift;
38 
39 #define	ZAP_MAGIC 0x2F52AB2ABULL
40 
41 #define	FZAP_BLOCK_SHIFT(zap)	((zap)->zap_f.zap_block_shift)
42 
43 #define	MZAP_ENT_LEN		64
44 #define	MZAP_NAME_LEN		(MZAP_ENT_LEN - 8 - 4 - 2)
45 #define	MZAP_MAX_BLKSHIFT	SPA_MAXBLOCKSHIFT
46 #define	MZAP_MAX_BLKSZ		(1 << MZAP_MAX_BLKSHIFT)
47 
48 #define	ZAP_NEED_CD		(-1U)
49 
50 typedef struct mzap_ent_phys {
51 	uint64_t mze_value;
52 	uint32_t mze_cd;
53 	uint16_t mze_pad;	/* in case we want to chain them someday */
54 	char mze_name[MZAP_NAME_LEN];
55 } mzap_ent_phys_t;
56 
57 typedef struct mzap_phys {
58 	uint64_t mz_block_type;	/* ZBT_MICRO */
59 	uint64_t mz_salt;
60 	uint64_t mz_normflags;
61 	uint64_t mz_pad[5];
62 	mzap_ent_phys_t mz_chunk[1];
63 	/* actually variable size depending on block size */
64 } mzap_phys_t;
65 
66 typedef struct mzap_ent {
67 	avl_node_t mze_node;
68 	int mze_chunkid;
69 	uint64_t mze_hash;
70 	mzap_ent_phys_t mze_phys;
71 } mzap_ent_t;
72 
73 /*
74  * The (fat) zap is stored in one object. It is an array of
75  * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:
76  *
77  * ptrtbl fits in first block:
78  * 	[zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...
79  *
80  * ptrtbl too big for first block:
81  * 	[zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...
82  *
83  */
84 
85 struct dmu_buf;
86 struct zap_leaf;
87 
88 #define	ZBT_LEAF		((1ULL << 63) + 0)
89 #define	ZBT_HEADER		((1ULL << 63) + 1)
90 #define	ZBT_MICRO		((1ULL << 63) + 3)
91 /* any other values are ptrtbl blocks */
92 
93 /*
94  * the embedded pointer table takes up half a block:
95  * block size / entry size (2^3) / 2
96  */
97 #define	ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)
98 
99 /*
100  * The embedded pointer table starts half-way through the block.  Since
101  * the pointer table itself is half the block, it starts at (64-bit)
102  * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).
103  */
104 #define	ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \
105 	((uint64_t *)(zap)->zap_f.zap_phys) \
106 	[(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]
107 
108 /*
109  * TAKE NOTE:
110  * If zap_phys_t is modified, zap_byteswap() must be modified.
111  */
112 typedef struct zap_phys {
113 	uint64_t zap_block_type;	/* ZBT_HEADER */
114 	uint64_t zap_magic;		/* ZAP_MAGIC */
115 
116 	struct zap_table_phys {
117 		uint64_t zt_blk;	/* starting block number */
118 		uint64_t zt_numblks;	/* number of blocks */
119 		uint64_t zt_shift;	/* bits to index it */
120 		uint64_t zt_nextblk;	/* next (larger) copy start block */
121 		uint64_t zt_blks_copied; /* number source blocks copied */
122 	} zap_ptrtbl;
123 
124 	uint64_t zap_freeblk;		/* the next free block */
125 	uint64_t zap_num_leafs;		/* number of leafs */
126 	uint64_t zap_num_entries;	/* number of entries */
127 	uint64_t zap_salt;		/* salt to stir into hash function */
128 	uint64_t zap_normflags;		/* flags for u8_textprep_str() */
129 	uint64_t zap_flags;		/* zap_flags_t */
130 	/*
131 	 * This structure is followed by padding, and then the embedded
132 	 * pointer table.  The embedded pointer table takes up second
133 	 * half of the block.  It is accessed using the
134 	 * ZAP_EMBEDDED_PTRTBL_ENT() macro.
135 	 */
136 } zap_phys_t;
137 
138 typedef struct zap_table_phys zap_table_phys_t;
139 
140 typedef struct zap {
141 	objset_t *zap_objset;
142 	uint64_t zap_object;
143 	struct dmu_buf *zap_dbuf;
144 	krwlock_t zap_rwlock;
145 	boolean_t zap_ismicro;
146 	int zap_normflags;
147 	uint64_t zap_salt;
148 	union {
149 		struct {
150 			zap_phys_t *zap_phys;
151 
152 			/*
153 			 * zap_num_entries_mtx protects
154 			 * zap_num_entries
155 			 */
156 			kmutex_t zap_num_entries_mtx;
157 			int zap_block_shift;
158 		} zap_fat;
159 		struct {
160 			mzap_phys_t *zap_phys;
161 			int16_t zap_num_entries;
162 			int16_t zap_num_chunks;
163 			int16_t zap_alloc_next;
164 			avl_tree_t zap_avl;
165 		} zap_micro;
166 	} zap_u;
167 } zap_t;
168 
169 typedef struct zap_name {
170 	zap_t *zn_zap;
171 	int zn_key_intlen;
172 	const void *zn_key_orig;
173 	int zn_key_orig_len;
174 	const void *zn_key_norm;
175 	int zn_key_norm_len;
176 	uint64_t zn_hash;
177 	matchtype_t zn_matchtype;
178 	char zn_normbuf[ZAP_MAXNAMELEN];
179 } zap_name_t;
180 
181 #define	zap_f	zap_u.zap_fat
182 #define	zap_m	zap_u.zap_micro
183 
184 boolean_t zap_match(zap_name_t *zn, const char *matchname);
185 int zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx,
186     krw_t lti, boolean_t fatreader, boolean_t adding, zap_t **zapp);
187 void zap_unlockdir(zap_t *zap);
188 void zap_evict(dmu_buf_t *db, void *vmzap);
189 zap_name_t *zap_name_alloc(zap_t *zap, const char *key, matchtype_t mt);
190 void zap_name_free(zap_name_t *zn);
191 int zap_hashbits(zap_t *zap);
192 uint32_t zap_maxcd(zap_t *zap);
193 uint64_t zap_getflags(zap_t *zap);
194 
195 #define	ZAP_HASH_IDX(hash, n) (((n) == 0) ? 0 : ((hash) >> (64 - (n))))
196 
197 void fzap_byteswap(void *buf, size_t size);
198 int fzap_count(zap_t *zap, uint64_t *count);
199 int fzap_lookup(zap_name_t *zn,
200     uint64_t integer_size, uint64_t num_integers, void *buf,
201     char *realname, int rn_len, boolean_t *normalization_conflictp);
202 int fzap_count_write(zap_name_t *zn, int add, uint64_t *towrite,
203     uint64_t *tooverwrite);
204 int fzap_add(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers,
205     const void *val, dmu_tx_t *tx);
206 int fzap_update(zap_name_t *zn,
207     int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx);
208 int fzap_length(zap_name_t *zn,
209     uint64_t *integer_size, uint64_t *num_integers);
210 int fzap_remove(zap_name_t *zn, dmu_tx_t *tx);
211 int fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za);
212 void fzap_get_stats(zap_t *zap, zap_stats_t *zs);
213 void zap_put_leaf(struct zap_leaf *l);
214 
215 int fzap_add_cd(zap_name_t *zn,
216     uint64_t integer_size, uint64_t num_integers,
217     const void *val, uint32_t cd, dmu_tx_t *tx);
218 void fzap_upgrade(zap_t *zap, dmu_tx_t *tx, zap_flags_t flags);
219 int fzap_cursor_move_to_key(zap_cursor_t *zc, zap_name_t *zn);
220 
221 #ifdef	__cplusplus
222 }
223 #endif
224 
225 #endif /* _SYS_ZAP_IMPL_H */
226