1 /*- 2 * Copyright (c) 2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/sys/kobj.h,v 1.8 2003/09/22 21:32:49 peter Exp $ 27 */ 28 29 #ifndef _SYS_KOBJ_H_ 30 #define _SYS_KOBJ_H_ 31 32 #ifndef _SYS_TYPES_H_ 33 #include <sys/types.h> 34 #endif 35 36 #if !defined(_KERNEL) && !defined(_KERNEL_STRUCTURES) 37 #error "This file should not be included by userland programs." 38 #endif 39 40 /* 41 * Forward declarations 42 */ 43 typedef struct kobj *kobj_t; 44 typedef struct kobj_class *kobj_class_t; 45 typedef const struct kobj_method kobj_method_t; 46 typedef int (*kobjop_t)(void); 47 typedef struct kobj_ops *kobj_ops_t; 48 typedef struct kobjop_desc *kobjop_desc_t; 49 struct malloc_type; 50 51 struct kobj_method { 52 kobjop_desc_t desc; 53 kobjop_t func; 54 }; 55 56 /* 57 * A class is simply a method table and a sizeof value. When the first 58 * instance of the class is created, the method table will be compiled 59 * into a form more suited to efficient method dispatch. This compiled 60 * method table is always the first field of the object. 61 */ 62 #define KOBJ_CLASS_FIELDS \ 63 const char *name; /* class name */ \ 64 kobj_method_t *methods; /* method table */ \ 65 size_t size; /* object size */ \ 66 kobj_class_t *baseclasses; /* base classes */ \ 67 u_int refs; /* reference count */ \ 68 kobj_ops_t ops; /* compiled method table */ \ 69 u_int gpri /* global probe/attach pri */ 70 71 struct kobj_class { 72 KOBJ_CLASS_FIELDS; 73 }; 74 75 /* 76 * Implementation of kobj. 77 */ 78 #define KOBJ_FIELDS \ 79 kobj_ops_t ops 80 81 struct kobj { 82 KOBJ_FIELDS; 83 }; 84 85 /* 86 * gpri values (higher values probe/attach first, allows us to 87 * default the field to 0). 88 */ 89 #define KOBJ_GPRI_ACPI 0x00FFU 90 #define KOBJ_GPRI_LAST 0x0000U 91 #define KOBJ_GPRI_DEFAULT KOBJ_GPRI_LAST 92 93 /* 94 * The ops table is used as a cache of results from kobj_lookup_method(). 95 */ 96 97 #define KOBJ_CACHE_SIZE 256 98 99 struct kobj_ops { 100 kobj_method_t *cache[KOBJ_CACHE_SIZE]; 101 kobj_class_t cls; 102 }; 103 104 struct kobjop_desc { 105 unsigned int id; /* unique ID */ 106 kobj_method_t deflt; /* default implementation */ 107 }; 108 109 /* 110 * Shorthand for constructing method tables. 111 */ 112 #define KOBJMETHOD(NAME, FUNC) { &NAME##_desc, (kobjop_t) FUNC } 113 #define KOBJMETHOD_END { NULL, NULL } 114 115 /* 116 * Declare a class (which should be defined in another file. 117 */ 118 #define DECLARE_CLASS(name) extern struct kobj_class name 119 120 /* 121 * Define a class with no base classes (api backward-compatible. with 122 * FreeBSD-5.1 and earlier). 123 */ 124 #define DEFINE_CLASS(name, methods, size) \ 125 DEFINE_CLASS_0(name, name ## _class, methods, size) 126 127 /* 128 * Define a class with no base classes. Use like this: 129 * 130 * DEFINE_CLASS_0(foo, foo_class, foo_methods, sizeof(foo_softc)); 131 */ 132 #define DEFINE_CLASS_0(name, classvar, methods, size) \ 133 \ 134 struct kobj_class classvar = { \ 135 #name, methods, size, NULL, 0, NULL \ 136 } 137 138 /* 139 * Define a class with no base classes using the named structure 140 * as an extension of the kobj_class structure. 141 */ 142 #define DEFINE_CLASS_EXT(name, classvar, methods, size, extname) \ 143 \ 144 struct extname classvar = { \ 145 #name, methods, size, NULL, 0, NULL \ 146 } 147 148 /* 149 * Define a class inheriting a single base class. Use like this: 150 * 151 * DEFINE_CLASS1(foo, foo_class, foo_methods, sizeof(foo_softc), 152 * bar); 153 */ 154 #define DEFINE_CLASS_1(name, classvar, methods, size, \ 155 base1) \ 156 \ 157 static kobj_class_t name ## _baseclasses[] = { \ 158 &base1, 0 \ 159 }; \ 160 struct kobj_class classvar = { \ 161 #name, methods, size, name ## _baseclasses \ 162 } 163 164 /* 165 * Define a class inheriting two base classes. Use like this: 166 * 167 * DEFINE_CLASS2(foo, foo_class, foo_methods, sizeof(foo_softc), 168 * bar, baz); 169 */ 170 #define DEFINE_CLASS_2(name, methods, size, \ 171 base1, base2) \ 172 \ 173 static kobj_class_t name ## _baseclasses[] = { \ 174 &base1, \ 175 &base2, 0 \ 176 }; \ 177 struct kobj_class name ## _class = { \ 178 #name, methods, size, name ## _baseclasses \ 179 } 180 181 /* 182 * Define a class inheriting three base classes. Use like this: 183 * 184 * DEFINE_CLASS3(foo, foo_class, foo_methods, sizeof(foo_softc), 185 * bar, baz, foobar); 186 */ 187 #define DEFINE_CLASS_3(name, methods, size, \ 188 base1, base2, base3) \ 189 \ 190 static kobj_class_t name ## _baseclasses[] = { \ 191 &base1, \ 192 &base2, \ 193 &base3, 0 \ 194 }; \ 195 struct kobj_class name ## _class = { \ 196 #name, methods, size, name ## _baseclasses \ 197 } 198 199 #ifdef _KERNEL 200 201 /* 202 * Compile class for the first instance and add a reference. 203 */ 204 void kobj_class_instantiate(kobj_class_t cls); 205 206 /* 207 * Remove a reference and free method table with the last instance. 208 */ 209 void kobj_class_uninstantiate(kobj_class_t cls); 210 211 /* 212 * Allocate memory for and initialise a new object. 213 */ 214 kobj_t kobj_create(kobj_class_t cls, 215 struct malloc_type *mtype, 216 int mflags); 217 218 /* 219 * Initialise a pre-allocated object. 220 */ 221 void kobj_init(kobj_t obj, kobj_class_t cls); 222 223 /* 224 * Delete an object. If mtype is non-zero, free the memory. 225 */ 226 void kobj_delete(kobj_t obj, struct malloc_type *mtype); 227 228 /* 229 * Lookup the method in the cache and if it isn't there look it up the 230 * slow way. 231 * 232 * We do the cache inside kobj_lookup_method() now, we don't try to 233 * expand it because it's really silly. These lookups are not in the 234 * critical path. 235 */ 236 237 #define KOBJOPLOOKUP(OPS,OP) do { \ 238 _m = kobj_lookup_method_cache(OPS->cls, &OPS->cache[0], \ 239 &OP##_##desc); \ 240 } while(0) 241 242 kobj_method_t *kobj_lookup_method(kobj_class_t cls, 243 kobj_method_t **cep, 244 kobjop_desc_t desc); 245 246 kobjop_t kobj_lookup_method_cache(kobj_class_t cls, 247 kobj_method_t **cep, 248 kobjop_desc_t desc); 249 250 /* 251 * Default method implementation. Returns ENXIO. 252 */ 253 int kobj_error_method(void); 254 255 #endif /* _KERNEL */ 256 257 #endif /* !_SYS_KOBJ_H_ */ 258