xref: /titanic_41/usr/src/lib/libpool/common/pool_impl.h (revision 6f45ec7b0b964c3be967c4880e8867ac1e7763a5)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef	_POOL_IMPL_H
28 #define	_POOL_IMPL_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #ifdef	__cplusplus
33 extern "C" {
34 #endif
35 
36 /*
37  * This file contains the definitions of types and supporting
38  * functions to implement the libpool generic data manipulation
39  * facility.
40  *
41  * libpool is designed so that the data representation/storage method
42  * used may be easily replaced without affecting core functionality.
43  * A libpool configuration is connected to a particular data
44  * representation/storage "driver" via the pool_connection_t
45  * type. When a configuration is opened (see pool_conf_open) the
46  * libpool implementation allocates a specific data manipulation type
47  * and initialises it. For instance, see pool_xml_connection_alloc.
48  *
49  * This function represents a cross-over point and all routines used
50  * for data representation/storage are controlled by the type of
51  * allocated connection.
52  *
53  * Currently, there are two implemented methods of access. Data may be
54  * retrieved from the kernel, using the pool_knl_connection_t
55  * function. This implementation relies on a private interface
56  * provided by a driver, /dev/pool, and presents data retrieved from
57  * the kernel via the standard libpool interface. Alternatively, data
58  * may be retrieved from an XML file, via pool_xml_connection_t, and
59  * presented through the standard libpool interface. For details of
60  * these two implementations, see pool_kernel_impl.h and
61  * pool_xml_impl.h.
62  *
63  * In addition to defining a specific connection type for a desired
64  * data representation/storage medium, several other structures must
65  * be defined to allow manipulation of configuration elements.
66  *
67  * Configuration elements are represented as pool_elem_t instances, or
68  * as sub-types of this generic type (such as pool_t, which represents
69  * a pool element) with groups (or sets) of these instances available
70  * for manipulation via the pool_result_set_t type.
71  *
72  * For more information on the implementation of these types, read the
73  * detailed comments above each structure definition.
74  */
75 
76 /*
77  * The pool_elem_t is used to represent a configuration element.The
78  * class of the element is stored within the structure along with a
79  * pointer to the containing configuration and a pointer to the
80  * element's specific subtype.
81  *
82  * The function pointers are initialised when the element is allocated
83  * to use the specific functions provided by the concrete data
84  * representation.
85  *
86  * The full set of operations that can be performed on an element
87  * which require special treatment from the data
88  * representation/storage medium are defined.
89  */
90 struct pool_elem {
91 	pool_conf_t *pe_conf;				/* Configuration */
92 	pool_elem_class_t pe_class;			/* Element class */
93 	pool_resource_elem_class_t pe_resource_class;	/* Resource class */
94 	pool_component_elem_class_t pe_component_class;	/* Component class */
95 	struct pool_elem *pe_pair;			/* Static pair */
96 	pool_value_class_t (*pe_get_prop)(const pool_elem_t *, const char *,
97 	    pool_value_t *);
98 	int (*pe_put_prop)(pool_elem_t *, const char *, const pool_value_t *);
99 	int (*pe_rm_prop)(pool_elem_t *, const char *);
100 	pool_value_t **(*pe_get_props)(const pool_elem_t *, uint_t *);
101 	int (*pe_remove)(pool_elem_t *);
102 	pool_elem_t *(*pe_get_container)(const pool_elem_t *);
103 	int (*pe_set_container)(pool_elem_t *, pool_elem_t *);
104 };
105 
106 /*
107  * libpool performs many operations against a pool_elem_t. This basic
108  * type is extended to provide specific functionality and type safety
109  * for each of the different types of element supported by
110  * libpool. There are four types of element:
111  * - pool_system_t, represents an entire configuration
112  * - pool_t, represents a single pool
113  * - pool_resource_t, represents a single resource
114  * - pool_component_t, represents a single resource component
115  *
116  * pool_system_t is an internal structure, the other structures are
117  * externally visible and form a major part of the libpool interface.
118  */
119 typedef struct pool_system
120 {
121 	pool_elem_t ps_elem;
122 	void *pe_pad1;
123 	void *pe_pad2;
124 } pool_system_t;
125 
126 struct pool
127 {
128 	pool_elem_t pp_elem;
129 	/*
130 	 * Specific to pool_t
131 	 */
132 	int (*pp_associate)(pool_t *, const pool_resource_t *);
133 	int (*pp_dissociate)(pool_t *, const pool_resource_t *);
134 };
135 
136 struct pool_resource
137 {
138 	pool_elem_t pr_elem;
139 	/*
140 	 * Specific to pool_resource_t
141 	 */
142 	int (*pr_is_system)(const pool_resource_t *);
143 	int (*pr_can_associate)(const pool_resource_t *);
144 };
145 
146 struct pool_component
147 {
148 	pool_elem_t pc_elem;
149 	void *pe_pad1;
150 	void *pe_pad2;
151 };
152 
153 /*
154  * The pool_result_set_t is used to represent a collection (set) of
155  * configuration elements. The configuration to which this result set
156  * applies is stored along with an indicator as to whether the result
157  * set is still in use.
158  *
159  * The function pointers are initialised when the element is allocated
160  * to use the specific functions provided by the concrete data
161  * representation.
162  *
163  * The full set of operations that can be performed on an element
164  * which require special treatment from the data
165  * representation/storage medium are defined.
166  */
167 typedef struct pool_result_set {
168 	pool_conf_t *prs_conf;				/* Configuration */
169 	int prs_active;					/* Query active? */
170 	int prs_index;					/* Result Index */
171 	pool_elem_t *(*prs_next)(struct pool_result_set *);
172 	pool_elem_t *(*prs_prev)(struct pool_result_set *);
173 	pool_elem_t *(*prs_first)(struct pool_result_set *);
174 	pool_elem_t *(*prs_last)(struct pool_result_set *);
175 	int (*prs_set_index)(struct pool_result_set *, int);
176 	int (*prs_get_index)(struct pool_result_set *);
177 	int (*prs_close)(struct pool_result_set *);
178 	int (*prs_count)(struct pool_result_set *);
179 } pool_result_set_t;
180 
181 /*
182  * The pool_connection_t is used to represent a connection between a
183  * libpool configuration and a particular implementation of the
184  * libpool interface in a specific data representation/storage medium,
185  * e.g. XML.
186  *
187  * The name of the storage medium is stored along with the type of the
188  * data store.
189  *
190  * The function pointers are initialised when the element is allocated
191  * to use the specific functions provided by the concrete data
192  * representation.
193  *
194  * The full set of operations that can be performed on an element
195  * which require special treatment from the data
196  * representation/storage medium are defined.
197  */
198 typedef struct pool_connection {
199 	const char *pc_name;				/* Provider name */
200 	int pc_store_type;				/* Datastore type */
201 	int pc_oflags;					/* Open flags */
202 	int (*pc_close)(pool_conf_t *);
203 	int (*pc_validate)(const pool_conf_t *, pool_valid_level_t);
204 	int (*pc_commit)(pool_conf_t *);
205 	int (*pc_export)(const pool_conf_t *, const char *,
206 	    pool_export_format_t);
207 	int (*pc_rollback)(pool_conf_t *);
208 	pool_result_set_t *(*pc_exec_query)(const pool_conf_t *,
209 	    const pool_elem_t *, const char *, pool_elem_class_t,
210 	    pool_value_t **);
211 	pool_elem_t *(*pc_elem_create)(pool_conf_t *, pool_elem_class_t,
212 	    pool_resource_elem_class_t, pool_component_elem_class_t);
213 	int (*pc_remove)(pool_conf_t *);
214 	int (*pc_res_xfer)(pool_resource_t *, pool_resource_t *, uint64_t);
215 	int (*pc_res_xxfer)(pool_resource_t *, pool_resource_t *,
216 	    pool_component_t **);
217 	char *(*pc_get_binding)(pool_conf_t *, pid_t);
218 	int (*pc_set_binding)(pool_conf_t *, const char *, idtype_t, id_t);
219 	char *(*pc_get_resource_binding)(pool_conf_t *,
220 	    pool_resource_elem_class_t, pid_t);
221 } pool_connection_t;
222 
223 /*
224  * pool_conf represents a resource management configuration. The
225  * configuration location is stored in the pc_location member with the
226  * state of the configuration stored in pc_state.
227  *
228  * The pc_prov member provides data representation/storage abstraction
229  * for the configuration since all access to data is performed through
230  * this member.
231  */
232 struct pool_conf {
233 	const char *pc_location;			/* Location */
234 	pool_connection_t *pc_prov;			/* Data Provider */
235 	pool_conf_state_t pc_state;			/* State */
236 };
237 
238 /*
239  * Convert a pool_elem_t to it's appropriate sub-type.
240  */
241 extern pool_system_t	*pool_conf_system(const pool_conf_t *);
242 extern pool_system_t	*pool_elem_system(const pool_elem_t *);
243 extern pool_t		*pool_elem_pool(const pool_elem_t *);
244 extern pool_resource_t	*pool_elem_res(const pool_elem_t *);
245 extern pool_component_t	*pool_elem_comp(const pool_elem_t *);
246 
247 /*
248  * Convert a pool_system_t to a pool_elem_t.
249  */
250 extern pool_elem_t	*pool_system_elem(const pool_system_t *);
251 
252 /*
253  * Get/Set an element's "pair" element. A pair element is a temporary
254  * association at commit between an element in the dynamic
255  * configuration and an element in the static configuration. This
256  * relationship is stored in the pe_pair member of the element.
257  */
258 extern pool_elem_t	*pool_get_pair(const pool_elem_t *);
259 extern void		pool_set_pair(pool_elem_t *, pool_elem_t *);
260 
261 /*
262  * Result Set Manipulation
263  */
264 extern pool_elem_t	*pool_rs_next(pool_result_set_t *);
265 extern pool_elem_t	*pool_rs_prev(pool_result_set_t *);
266 extern pool_elem_t	*pool_rs_first(pool_result_set_t *);
267 extern pool_elem_t	*pool_rs_last(pool_result_set_t *);
268 extern int		pool_rs_count(pool_result_set_t *);
269 extern int		pool_rs_get_index(pool_result_set_t *);
270 extern int		pool_rs_set_index(pool_result_set_t *, int);
271 extern int		pool_rs_close(pool_result_set_t *);
272 
273 /*
274  * General Purpose Query
275  */
276 extern pool_result_set_t *pool_exec_query(const pool_conf_t *,
277     const pool_elem_t *, const char *, pool_elem_class_t, pool_value_t **);
278 
279 #ifdef	__cplusplus
280 }
281 #endif
282 
283 #endif	/* _POOL_IMPL_H */
284