1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2000,2003 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #ifndef _SYS_KOBJ_H_ 32 #define _SYS_KOBJ_H_ 33 34 #include <sys/types.h> 35 #include "los_typedef.h" 36 37 /* 38 * Forward declarations 39 */ 40 typedef struct kobj *kobj_t; 41 typedef struct kobj_class *kobj_class_t; 42 typedef const struct kobj_method kobj_method_t; 43 typedef int (*kobjop_t)(void); 44 typedef struct kobj_ops *kobj_ops_t; 45 typedef struct kobjop_desc *kobjop_desc_t; 46 struct malloc_type; 47 48 struct kobj_method { 49 kobjop_desc_t desc; 50 kobjop_t func; 51 }; 52 53 /* 54 * A class is simply a method table and a sizeof value. When the first 55 * instance of the class is created, the method table will be compiled 56 * into a form more suited to efficient method dispatch. This compiled 57 * method table is always the first field of the object. 58 */ 59 #define KOBJ_CLASS_FIELDS \ 60 const char *name; /* class name */ \ 61 kobj_method_t *methods; /* method table */ \ 62 size_t size; /* object size */ \ 63 kobj_class_t *baseclasses; /* base classes */ \ 64 u_int refs; /* reference count */ \ 65 kobj_ops_t ops /* compiled method table */ 66 67 struct kobj_class { 68 KOBJ_CLASS_FIELDS; 69 }; 70 71 /* 72 * Implementation of kobj. 73 */ 74 #define KOBJ_FIELDS \ 75 kobj_ops_t ops 76 77 struct kobj { 78 KOBJ_FIELDS; 79 }; 80 81 /* 82 * The ops table is used as a cache of results from kobj_lookup_method(). 83 */ 84 85 #define KOBJ_CACHE_SIZE 256 86 87 struct kobj_ops { 88 kobj_method_t *cache[KOBJ_CACHE_SIZE]; 89 kobj_class_t cls; 90 }; 91 92 struct kobjop_desc { 93 unsigned int id; /* unique ID */ 94 kobj_method_t deflt; /* default implementation */ 95 }; 96 97 /* 98 * Shorthand for constructing method tables. 99 * The ternary operator is (ab)used to provoke a warning when FUNC 100 * has a signature that is not compatible with kobj method signature. 101 */ 102 #define KOBJMETHOD(NAME, FUNC) \ 103 { &NAME##_desc, (kobjop_t) (1 ? FUNC : (NAME##_t *)NULL) } 104 105 /* 106 * 107 */ 108 #define KOBJMETHOD_END { NULL, NULL } 109 110 /* 111 * Declare a class (which should be defined in another file. 112 */ 113 #define DECLARE_CLASS(name) extern struct kobj_class name 114 115 /* 116 * Define a class with no base classes (api backward-compatible. with 117 * FreeBSD-5.1 and earlier). 118 */ 119 #define DEFINE_CLASS(name, methods, size) \ 120 DEFINE_CLASS_0(name, name ## _class, methods, size) 121 122 /* 123 * Define a class with no base classes. Use like this: 124 * 125 * DEFINE_CLASS_0(foo, foo_class, foo_methods, sizeof(foo_softc)); 126 */ 127 #define DEFINE_CLASS_0(name, classvar, methods, size) \ 128 \ 129 struct kobj_class classvar = { \ 130 #name, methods, size, NULL \ 131 } 132 133 /* 134 * Define a class inheriting a single base class. Use like this: 135 * 136 * DEFINE_CLASS_1(foo, foo_class, foo_methods, sizeof(foo_softc), 137 * bar); 138 */ 139 #define DEFINE_CLASS_1(name, classvar, methods, size, \ 140 base1) \ 141 \ 142 static kobj_class_t name ## _baseclasses[] = \ 143 { &base1, NULL }; \ 144 struct kobj_class classvar = { \ 145 #name, methods, size, name ## _baseclasses \ 146 } 147 148 /* 149 * Define a class inheriting two base classes. Use like this: 150 * 151 * DEFINE_CLASS_2(foo, foo_class, foo_methods, sizeof(foo_softc), 152 * bar, baz); 153 */ 154 #define DEFINE_CLASS_2(name, classvar, methods, size, \ 155 base1, base2) \ 156 \ 157 static kobj_class_t name ## _baseclasses[] = \ 158 { &base1, \ 159 &base2, NULL }; \ 160 struct kobj_class classvar = { \ 161 #name, methods, size, name ## _baseclasses \ 162 } 163 164 /* 165 * Define a class inheriting three base classes. Use like this: 166 * 167 * DEFINE_CLASS_3(foo, foo_class, foo_methods, sizeof(foo_softc), 168 * bar, baz, foobar); 169 */ 170 #define DEFINE_CLASS_3(name, classvar, methods, size, \ 171 base1, base2, base3) \ 172 \ 173 static kobj_class_t name ## _baseclasses[] = \ 174 { &base1, \ 175 &base2, \ 176 &base3, NULL }; \ 177 struct kobj_class classvar = { \ 178 #name, methods, size, name ## _baseclasses \ 179 } 180 181 /* 182 * Compile the method table in a class. 183 */ 184 void kobj_class_compile(kobj_class_t cls); 185 186 /* 187 * Compile the method table, with the caller providing the space for 188 * the ops table.(for use before malloc is initialised). 189 */ 190 void kobj_class_compile_static(kobj_class_t cls, kobj_ops_t ops); 191 192 /* 193 * Free the compiled method table in a class. 194 */ 195 void kobj_class_free(kobj_class_t cls); 196 197 /* 198 * Allocate memory for and initialise a new object. 199 */ 200 kobj_t kobj_create(kobj_class_t cls, 201 struct malloc_type *mtype, 202 int mflags); 203 204 /* 205 * Initialise a pre-allocated object. 206 */ 207 void kobj_init(kobj_t obj, kobj_class_t cls); 208 void kobj_init_static(kobj_t obj, kobj_class_t cls); 209 210 /* 211 * Delete an object. If mtype is non-zero, free the memory. 212 */ 213 void kobj_delete(kobj_t obj, struct malloc_type *mtype); 214 215 /* 216 * Maintain stats on hits/misses in lookup caches. 217 */ 218 #ifdef KOBJ_STATS 219 extern u_int kobj_lookup_hits; 220 extern u_int kobj_lookup_misses; 221 #endif 222 223 /* 224 * Lookup the method in the cache and if it isn't there look it up the 225 * slow way. 226 */ 227 #ifdef KOBJ_STATS 228 #define KOBJOPLOOKUP(OPS,OP) do { \ 229 kobjop_desc_t _desc = &OP##_##desc; \ 230 kobj_method_t **_cep = \ 231 &OPS->cache[_desc->id & (KOBJ_CACHE_SIZE-1)]; \ 232 kobj_method_t *_ce = *_cep; \ 233 if (_ce->desc != _desc) { \ 234 _ce = kobj_lookup_method(OPS->cls, \ 235 _cep, _desc); \ 236 kobj_lookup_misses++; \ 237 } else \ 238 kobj_lookup_hits++; \ 239 _m = _ce->func; \ 240 } while(0) 241 #else 242 #define KOBJOPLOOKUP(OPS,OP) do { \ 243 kobjop_desc_t _desc = &OP##_##desc; \ 244 kobj_method_t **_cep = \ 245 &OPS->cache[_desc->id & (KOBJ_CACHE_SIZE-1)]; \ 246 kobj_method_t *_ce = *_cep; \ 247 if (_ce->desc != _desc) \ 248 _ce = kobj_lookup_method(OPS->cls, \ 249 _cep, _desc); \ 250 _m = _ce->func; \ 251 } while(0) 252 #endif 253 254 kobj_method_t* kobj_lookup_method(kobj_class_t cls, 255 kobj_method_t **cep, 256 kobjop_desc_t desc); 257 258 /* 259 * Default method implementation. Returns ENXIO. 260 */ 261 int kobj_error_method(void); 262 263 void kobj_init_mutex(void *arg); 264 265 #endif /* !_SYS_KOBJ_H_ */ 266