xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/sa_impl.h (revision a6bde1a23b60f140c7ed78df979c2e22b1ed9b2c)
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) 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2013 by Delphix. All rights reserved.
24  */
25 
26 #ifndef	_SYS_SA_IMPL_H
27 #define	_SYS_SA_IMPL_H
28 
29 #include <sys/dmu.h>
30 #include <sys/refcount.h>
31 #include <sys/list.h>
32 
33 /*
34  * Array of known attributes and their
35  * various characteristics.
36  */
37 typedef struct sa_attr_table {
38 	sa_attr_type_t	sa_attr;
39 	uint8_t sa_registered;
40 	uint16_t sa_length;
41 	sa_bswap_type_t sa_byteswap;
42 	char *sa_name;
43 } sa_attr_table_t;
44 
45 /*
46  * Zap attribute format for attribute registration
47  *
48  * 64      56      48      40      32      24      16      8       0
49  * +-------+-------+-------+-------+-------+-------+-------+-------+
50  * |        unused         |      len      | bswap |   attr num    |
51  * +-------+-------+-------+-------+-------+-------+-------+-------+
52  *
53  * Zap attribute format for layout information.
54  *
55  * layout information is stored as an array of attribute numbers
56  * The name of the attribute is the layout number (0, 1, 2, ...)
57  *
58  * 16       0
59  * +---- ---+
60  * | attr # |
61  * +--------+
62  * | attr # |
63  * +--- ----+
64  *  ......
65  *
66  */
67 
68 #define	ATTR_BSWAP(x)	BF32_GET(x, 16, 8)
69 #define	ATTR_LENGTH(x)	BF32_GET(x, 24, 16)
70 #define	ATTR_NUM(x)	BF32_GET(x, 0, 16)
71 #define	ATTR_ENCODE(x, attr, length, bswap) \
72 { \
73 	BF64_SET(x, 24, 16, length); \
74 	BF64_SET(x, 16, 8, bswap); \
75 	BF64_SET(x, 0, 16, attr); \
76 }
77 
78 #define	TOC_OFF(x)		BF32_GET(x, 0, 23)
79 #define	TOC_ATTR_PRESENT(x)	BF32_GET(x, 31, 1)
80 #define	TOC_LEN_IDX(x)		BF32_GET(x, 24, 4)
81 #define	TOC_ATTR_ENCODE(x, len_idx, offset) \
82 { \
83 	BF32_SET(x, 31, 1, 1); \
84 	BF32_SET(x, 24, 7, len_idx); \
85 	BF32_SET(x, 0, 24, offset); \
86 }
87 
88 #define	SA_LAYOUTS	"LAYOUTS"
89 #define	SA_REGISTRY	"REGISTRY"
90 
91 /*
92  * Each unique layout will have their own table
93  * sa_lot (layout_table)
94  */
95 typedef struct sa_lot {
96 	avl_node_t lot_num_node;
97 	avl_node_t lot_hash_node;
98 	uint64_t lot_num;
99 	uint64_t lot_hash;
100 	sa_attr_type_t *lot_attrs;	/* array of attr #'s */
101 	uint32_t lot_var_sizes;	/* how many aren't fixed size */
102 	uint32_t lot_attr_count;	/* total attr count */
103 	list_t 	lot_idx_tab;	/* should be only a couple of entries */
104 	int	lot_instance;	/* used with lot_hash to identify entry */
105 } sa_lot_t;
106 
107 /* index table of offsets */
108 typedef struct sa_idx_tab {
109 	list_node_t	sa_next;
110 	sa_lot_t	*sa_layout;
111 	uint16_t	*sa_variable_lengths;
112 	refcount_t	sa_refcount;
113 	uint32_t	*sa_idx_tab;	/* array of offsets */
114 } sa_idx_tab_t;
115 
116 /*
117  * Since the offset/index information into the actual data
118  * will usually be identical we can share that information with
119  * all handles that have the exact same offsets.
120  *
121  * You would typically only have a large number of different table of
122  * contents if you had a several variable sized attributes.
123  *
124  * Two AVL trees are used to track the attribute layout numbers.
125  * one is keyed by number and will be consulted when a DMU_OT_SA
126  * object is first read.  The second tree is keyed by the hash signature
127  * of the attributes and will be consulted when an attribute is added
128  * to determine if we already have an instance of that layout.  Both
129  * of these tree's are interconnected.  The only difference is that
130  * when an entry is found in the "hash" tree the list of attributes will
131  * need to be compared against the list of attributes you have in hand.
132  * The assumption is that typically attributes will just be updated and
133  * adding a completely new attribute is a very rare operation.
134  */
135 struct sa_os {
136 	kmutex_t 	sa_lock;
137 	boolean_t	sa_need_attr_registration;
138 	boolean_t	sa_force_spill;
139 	uint64_t	sa_master_obj;
140 	uint64_t	sa_reg_attr_obj;
141 	uint64_t	sa_layout_attr_obj;
142 	int		sa_num_attrs;
143 	sa_attr_table_t *sa_attr_table;	 /* private attr table */
144 	sa_update_cb_t	*sa_update_cb;
145 	avl_tree_t	sa_layout_num_tree;  /* keyed by layout number */
146 	avl_tree_t	sa_layout_hash_tree; /* keyed by layout hash value */
147 	int		sa_user_table_sz;
148 	sa_attr_type_t	*sa_user_table; /* user name->attr mapping table */
149 };
150 
151 /*
152  * header for all bonus and spill buffers.
153  *
154  * The header has a fixed portion with a variable number
155  * of "lengths" depending on the number of variable sized
156  * attributes which are determined by the "layout number"
157  */
158 
159 #define	SA_MAGIC	0x2F505A  /* ZFS SA */
160 typedef struct sa_hdr_phys {
161 	uint32_t sa_magic;
162 	/* BEGIN CSTYLED */
163 	/*
164 	 * Encoded with hdrsize and layout number as follows:
165 	 * 16      10       0
166 	 * +--------+-------+
167 	 * | hdrsz  |layout |
168 	 * +--------+-------+
169 	 *
170 	 * Bits 0-10 are the layout number
171 	 * Bits 11-16 are the size of the header.
172 	 * The hdrsize is the number * 8
173 	 *
174 	 * For example.
175 	 * hdrsz of 1 ==> 8 byte header
176 	 *          2 ==> 16 byte header
177 	 *
178 	 */
179 	/* END CSTYLED */
180 	uint16_t sa_layout_info;
181 	uint16_t sa_lengths[1];	/* optional sizes for variable length attrs */
182 	/* ... Data follows the lengths.  */
183 } sa_hdr_phys_t;
184 
185 #define	SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
186 #define	SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 6, 3, 0)
187 #define	SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
188 { \
189 	BF32_SET_SB(x, 10, 6, 3, 0, size); \
190 	BF32_SET(x, 0, 10, num); \
191 }
192 
193 typedef enum sa_buf_type {
194 	SA_BONUS = 1,
195 	SA_SPILL = 2
196 } sa_buf_type_t;
197 
198 typedef enum sa_data_op {
199 	SA_LOOKUP,
200 	SA_UPDATE,
201 	SA_ADD,
202 	SA_REPLACE,
203 	SA_REMOVE
204 } sa_data_op_t;
205 
206 /*
207  * Opaque handle used for most sa functions
208  *
209  * This needs to be kept as small as possible.
210  */
211 
212 struct sa_handle {
213 	kmutex_t	sa_lock;
214 	dmu_buf_t	*sa_bonus;
215 	dmu_buf_t	*sa_spill;
216 	objset_t	*sa_os;
217 	void 		*sa_userp;
218 	sa_idx_tab_t	*sa_bonus_tab;	 /* idx of bonus */
219 	sa_idx_tab_t	*sa_spill_tab; /* only present if spill activated */
220 };
221 
222 #define	SA_GET_DB(hdl, type)	\
223 	(dmu_buf_impl_t *)((type == SA_BONUS) ? hdl->sa_bonus : hdl->sa_spill)
224 
225 #define	SA_GET_HDR(hdl, type) \
226 	((sa_hdr_phys_t *)((dmu_buf_impl_t *)(SA_GET_DB(hdl, \
227 	type))->db.db_data))
228 
229 #define	SA_IDX_TAB_GET(hdl, type) \
230 	(type == SA_BONUS ? hdl->sa_bonus_tab : hdl->sa_spill_tab)
231 
232 #define	IS_SA_BONUSTYPE(a)	\
233 	((a == DMU_OT_SA) ? B_TRUE : B_FALSE)
234 
235 #define	SA_BONUSTYPE_FROM_DB(db) \
236 	(dmu_get_bonustype((dmu_buf_t *)db))
237 
238 #define	SA_BLKPTR_SPACE	(DN_MAX_BONUSLEN - sizeof (blkptr_t))
239 
240 #define	SA_LAYOUT_NUM(x, type) \
241 	((!IS_SA_BONUSTYPE(type) ? 0 : (((IS_SA_BONUSTYPE(type)) && \
242 	((SA_HDR_LAYOUT_NUM(x)) == 0)) ? 1 : SA_HDR_LAYOUT_NUM(x))))
243 
244 
245 #define	SA_REGISTERED_LEN(sa, attr) sa->sa_attr_table[attr].sa_length
246 
247 #define	SA_ATTR_LEN(sa, idx, attr, hdr) ((SA_REGISTERED_LEN(sa, attr) == 0) ?\
248 	hdr->sa_lengths[TOC_LEN_IDX(idx->sa_idx_tab[attr])] : \
249 	SA_REGISTERED_LEN(sa, attr))
250 
251 #define	SA_SET_HDR(hdr, num, size) \
252 	{ \
253 		hdr->sa_magic = SA_MAGIC; \
254 		SA_HDR_LAYOUT_INFO_ENCODE(hdr->sa_layout_info, num, size); \
255 	}
256 
257 #define	SA_ATTR_INFO(sa, idx, hdr, attr, bulk, type, hdl) \
258 	{ \
259 		bulk.sa_size = SA_ATTR_LEN(sa, idx, attr, hdr); \
260 		bulk.sa_buftype = type; \
261 		bulk.sa_addr = \
262 		    (void *)((uintptr_t)TOC_OFF(idx->sa_idx_tab[attr]) + \
263 		    (uintptr_t)hdr); \
264 }
265 
266 #define	SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) \
267 	(SA_HDR_SIZE(hdr) == (sizeof (sa_hdr_phys_t) + \
268 	(tb->lot_var_sizes > 1 ? P2ROUNDUP((tb->lot_var_sizes - 1) * \
269 	sizeof (uint16_t), 8) : 0)))
270 
271 int sa_add_impl(sa_handle_t *, sa_attr_type_t,
272     uint32_t, sa_data_locator_t, void *, dmu_tx_t *);
273 
274 void sa_register_update_callback_locked(objset_t *, sa_update_cb_t *);
275 int sa_size_locked(sa_handle_t *, sa_attr_type_t, int *);
276 
277 void sa_default_locator(void **, uint32_t *, uint32_t, boolean_t, void *);
278 int sa_attr_size(sa_os_t *, sa_idx_tab_t *, sa_attr_type_t,
279     uint16_t *, sa_hdr_phys_t *);
280 
281 #ifdef	__cplusplus
282 extern "C" {
283 #endif
284 
285 #ifdef	__cplusplus
286 }
287 #endif
288 
289 #endif	/* _SYS_SA_IMPL_H */
290