xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/sa_impl.h (revision e5803b76927480e8f9b67b22201c484ccf4c2bcf)
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  */
24 
25 #ifndef	_SYS_SA_IMPL_H
26 #define	_SYS_SA_IMPL_H
27 
28 #include <sys/dmu.h>
29 #include <sys/refcount.h>
30 #include <sys/list.h>
31 
32 /*
33  * Array of known attributes and their
34  * various characteristics.
35  */
36 typedef struct sa_attr_table {
37 	sa_attr_type_t	sa_attr;
38 	uint8_t sa_registered;
39 	uint16_t sa_length;
40 	sa_bswap_type_t sa_byteswap;
41 	char *sa_name;
42 } sa_attr_table_t;
43 
44 /*
45  * Zap attribute format for attribute registration
46  *
47  * 64      56      48      40      32      24      16      8       0
48  * +-------+-------+-------+-------+-------+-------+-------+-------+
49  * |        unused         |      len      | bswap |   attr num    |
50  * +-------+-------+-------+-------+-------+-------+-------+-------+
51  *
52  * Zap attribute format for layout information.
53  *
54  * layout information is stored as an array of attribute numbers
55  * The name of the attribute is the layout number (0, 1, 2, ...)
56  *
57  * 16       0
58  * +---- ---+
59  * | attr # |
60  * +--------+
61  * | attr # |
62  * +--- ----+
63  *  ......
64  *
65  */
66 
67 #define	ATTR_BSWAP(x)	BF32_GET(x, 16, 8)
68 #define	ATTR_LENGTH(x)	BF32_GET(x, 24, 16)
69 #define	ATTR_NUM(x)	BF32_GET(x, 0, 16)
70 #define	ATTR_ENCODE(x, attr, length, bswap) \
71 { \
72 	BF64_SET(x, 24, 16, length); \
73 	BF64_SET(x, 16, 8, bswap); \
74 	BF64_SET(x, 0, 16, attr); \
75 }
76 
77 #define	TOC_OFF(x)		BF32_GET(x, 0, 23)
78 #define	TOC_ATTR_PRESENT(x)	BF32_GET(x, 31, 1)
79 #define	TOC_LEN_IDX(x)		BF32_GET(x, 24, 4)
80 #define	TOC_ATTR_ENCODE(x, len_idx, offset) \
81 { \
82 	BF32_SET(x, 31, 1, 1); \
83 	BF32_SET(x, 24, 7, len_idx); \
84 	BF32_SET(x, 0, 24, offset); \
85 }
86 
87 #define	SA_LAYOUTS	"LAYOUTS"
88 #define	SA_REGISTRY	"REGISTRY"
89 
90 /*
91  * Each unique layout will have their own table
92  * sa_lot (layout_table)
93  */
94 typedef struct sa_lot {
95 	avl_node_t lot_num_node;
96 	avl_node_t lot_hash_node;
97 	uint64_t lot_num;
98 	uint64_t lot_hash;
99 	sa_attr_type_t *lot_attrs;	/* array of attr #'s */
100 	uint32_t lot_var_sizes;	/* how many aren't fixed size */
101 	uint32_t lot_attr_count;	/* total attr count */
102 	list_t 	lot_idx_tab;	/* should be only a couple of entries */
103 	int	lot_instance;	/* used with lot_hash to identify entry */
104 } sa_lot_t;
105 
106 /* index table of offsets */
107 typedef struct sa_idx_tab {
108 	list_node_t	sa_next;
109 	sa_lot_t	*sa_layout;
110 	uint16_t	*sa_variable_lengths;
111 	refcount_t	sa_refcount;
112 	uint32_t	*sa_idx_tab;	/* array of offsets */
113 } sa_idx_tab_t;
114 
115 /*
116  * Since the offset/index information into the actual data
117  * will usually be identical we can share that information with
118  * all handles that have the exact same offsets.
119  *
120  * You would typically only have a large number of different table of
121  * contents if you had a several variable sized attributes.
122  *
123  * Two AVL trees are used to track the attribute layout numbers.
124  * one is keyed by number and will be consulted when a DMU_OT_SA
125  * object is first read.  The second tree is keyed by the hash signature
126  * of the attributes and will be consulted when an attribute is added
127  * to determine if we already have an instance of that layout.  Both
128  * of these tree's are interconnected.  The only difference is that
129  * when an entry is found in the "hash" tree the list of attributes will
130  * need to be compared against the list of attributes you have in hand.
131  * The assumption is that typically attributes will just be updated and
132  * adding a completely new attribute is a very rare operation.
133  */
134 struct sa_os {
135 	kmutex_t 	sa_lock;
136 	boolean_t	sa_need_attr_registration;
137 	boolean_t	sa_force_spill;
138 	uint64_t	sa_master_obj;
139 	uint64_t	sa_reg_attr_obj;
140 	uint64_t	sa_layout_attr_obj;
141 	int		sa_num_attrs;
142 	sa_attr_table_t *sa_attr_table;	 /* private attr table */
143 	sa_update_cb_t	*sa_update_cb;
144 	avl_tree_t	sa_layout_num_tree;  /* keyed by layout number */
145 	avl_tree_t	sa_layout_hash_tree; /* keyed by layout hash value */
146 	int		sa_user_table_sz;
147 	sa_attr_type_t	*sa_user_table; /* user name->attr mapping table */
148 };
149 
150 /*
151  * header for all bonus and spill buffers.
152  * The header has a fixed portion with a variable number
153  * of "lengths" depending on the number of variable sized
154  * attribues which are determined by the "layout number"
155  */
156 
157 #define	SA_MAGIC	0x2F505A  /* ZFS SA */
158 typedef struct sa_hdr_phys {
159 	uint32_t sa_magic;
160 	uint16_t sa_layout_info;  /* Encoded with hdrsize and layout number */
161 	uint16_t sa_lengths[1];	/* optional sizes for variable length attrs */
162 	/* ... Data follows the lengths.  */
163 } sa_hdr_phys_t;
164 
165 /*
166  * sa_hdr_phys -> sa_layout_info
167  *
168  * 16      10       0
169  * +--------+-------+
170  * | hdrsz  |layout |
171  * +--------+-------+
172  *
173  * Bits 0-10 are the layout number
174  * Bits 11-16 are the size of the header.
175  * The hdrsize is the number * 8
176  *
177  * For example.
178  * hdrsz of 1 ==> 8 byte header
179  *          2 ==> 16 byte header
180  *
181  */
182 
183 #define	SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
184 #define	SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 16, 3, 0)
185 #define	SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
186 { \
187 	BF32_SET_SB(x, 10, 6, 3, 0, size); \
188 	BF32_SET(x, 0, 10, num); \
189 }
190 
191 typedef enum sa_buf_type {
192 	SA_BONUS = 1,
193 	SA_SPILL = 2
194 } sa_buf_type_t;
195 
196 typedef enum sa_data_op {
197 	SA_LOOKUP,
198 	SA_UPDATE,
199 	SA_ADD,
200 	SA_REPLACE,
201 	SA_REMOVE
202 } sa_data_op_t;
203 
204 /*
205  * Opaque handle used for most sa functions
206  *
207  * This needs to be kept as small as possible.
208  */
209 
210 struct sa_handle {
211 	kmutex_t	sa_lock;
212 	dmu_buf_t	*sa_bonus;
213 	dmu_buf_t	*sa_spill;
214 	objset_t	*sa_os;
215 	void 		*sa_userp;
216 	sa_idx_tab_t	*sa_bonus_tab;	 /* idx of bonus */
217 	sa_idx_tab_t	*sa_spill_tab; /* only present if spill activated */
218 };
219 
220 #define	SA_GET_DB(hdl, type)	\
221 	(dmu_buf_impl_t *)((type == SA_BONUS) ? hdl->sa_bonus : hdl->sa_spill)
222 
223 #define	SA_GET_HDR(hdl, type) \
224 	((sa_hdr_phys_t *)((dmu_buf_impl_t *)(SA_GET_DB(hdl, \
225 	type))->db.db_data))
226 
227 #define	SA_IDX_TAB_GET(hdl, type) \
228 	(type == SA_BONUS ? hdl->sa_bonus_tab : hdl->sa_spill_tab)
229 
230 #define	IS_SA_BONUSTYPE(a)	\
231 	((a == DMU_OT_SA) ? B_TRUE : B_FALSE)
232 
233 #define	SA_BONUSTYPE_FROM_DB(db) \
234 	(dmu_get_bonustype((dmu_buf_t *)db))
235 
236 #define	SA_BLKPTR_SPACE	(DN_MAX_BONUSLEN - sizeof (blkptr_t))
237 
238 #define	SA_LAYOUT_NUM(x, type) \
239 	((!IS_SA_BONUSTYPE(type) ? 0 : (((IS_SA_BONUSTYPE(type)) && \
240 	((SA_HDR_LAYOUT_NUM(x)) == 0)) ? 1 : SA_HDR_LAYOUT_NUM(x))))
241 
242 
243 #define	SA_REGISTERED_LEN(sa, attr) sa->sa_attr_table[attr].sa_length
244 
245 #define	SA_ATTR_LEN(sa, idx, attr, hdr) ((SA_REGISTERED_LEN(sa, attr) == 0) ?\
246 	hdr->sa_lengths[TOC_LEN_IDX(idx->sa_idx_tab[attr])] : \
247 	SA_REGISTERED_LEN(sa, attr))
248 
249 #define	SA_SET_HDR(hdr, num, size) \
250 	{ \
251 		hdr->sa_magic = SA_MAGIC; \
252 		SA_HDR_LAYOUT_INFO_ENCODE(hdr->sa_layout_info, num, size); \
253 	}
254 
255 #define	SA_ATTR_INFO(sa, idx, hdr, attr, bulk, type, hdl) \
256 	{ \
257 		bulk.sa_size = SA_ATTR_LEN(sa, idx, attr, hdr); \
258 		bulk.sa_buftype = type; \
259 		bulk.sa_addr = \
260 		    (void *)((uintptr_t)TOC_OFF(idx->sa_idx_tab[attr]) + \
261 		    (uintptr_t)hdr); \
262 }
263 
264 #define	SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) \
265 	(SA_HDR_SIZE(hdr) == (sizeof (sa_hdr_phys_t) + \
266 	(tb->lot_var_sizes > 1 ? P2ROUNDUP((tb->lot_var_sizes - 1) * \
267 	sizeof (uint16_t), 8) : 0)))
268 
269 int sa_add_impl(sa_handle_t *, sa_attr_type_t,
270     uint32_t, sa_data_locator_t, void *, dmu_tx_t *);
271 
272 void sa_register_update_callback_locked(objset_t *, sa_update_cb_t *);
273 int sa_size_locked(sa_handle_t *, sa_attr_type_t, int *);
274 
275 void sa_default_locator(void **, uint32_t *, uint32_t, boolean_t, void *);
276 int sa_attr_size(sa_os_t *, sa_idx_tab_t *, sa_attr_type_t,
277     uint16_t *, sa_hdr_phys_t *);
278 
279 #ifdef	__cplusplus
280 extern "C" {
281 #endif
282 
283 #ifdef	__cplusplus
284 }
285 #endif
286 
287 #endif	/* _SYS_SA_IMPL_H */
288