1 /* 2 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org> 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 unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 * 28 */ 29 30 /* 31 * uma.h - External definitions for the Universal Memory Allocator 32 * 33 */ 34 35 #ifndef VM_UMA_H 36 #define VM_UMA_H 37 38 #include <sys/param.h> /* For NULL */ 39 #include <sys/malloc.h> /* For M_* */ 40 41 /* User visable parameters */ 42 #define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */ 43 44 /* Types and type defs */ 45 46 struct uma_zone; 47 /* Opaque type used as a handle to the zone */ 48 typedef struct uma_zone * uma_zone_t; 49 50 /* 51 * Item constructor 52 * 53 * Arguments: 54 * item A pointer to the memory which has been allocated. 55 * arg The arg field passed to uma_zalloc_arg 56 * size The size of the allocated item 57 * 58 * Returns: 59 * Nothing 60 * 61 * Discussion: 62 * The constructor is called just before the memory is returned 63 * to the user. It may block if necessary. 64 */ 65 typedef void (*uma_ctor)(void *mem, int size, void *arg); 66 67 /* 68 * Item destructor 69 * 70 * Arguments: 71 * item A pointer to the memory which has been allocated. 72 * size The size of the item being destructed. 73 * arg Argument passed through uma_zfree_arg 74 * 75 * Returns: 76 * Nothing 77 * 78 * Discussion: 79 * The destructor may perform operations that differ from those performed 80 * by the initializer, but it must leave the object in the same state. 81 * This IS type stable storage. This is called after EVERY zfree call. 82 */ 83 typedef void (*uma_dtor)(void *mem, int size, void *arg); 84 85 /* 86 * Item initializer 87 * 88 * Arguments: 89 * item A pointer to the memory which has been allocated. 90 * size The size of the item being initialized. 91 * 92 * Returns: 93 * Nothing 94 * 95 * Discussion: 96 * The initializer is called when the memory is cached in the uma zone. 97 * this should be the same state that the destructor leaves the object in. 98 */ 99 typedef void (*uma_init)(void *mem, int size); 100 101 /* 102 * Item discard function 103 * 104 * Arguments: 105 * item A pointer to memory which has been 'freed' but has not left the 106 * zone's cache. 107 * size The size of the item being discarded. 108 * 109 * Returns: 110 * Nothing 111 * 112 * Discussion: 113 * This routine is called when memory leaves a zone and is returned to the 114 * system for other uses. It is the counter part to the init function. 115 */ 116 typedef void (*uma_fini)(void *mem, int size); 117 118 /* 119 * What's the difference between initializing and constructing? 120 * 121 * The item is initialized when it is cached, and this is the state that the 122 * object should be in when returned to the allocator. The purpose of this is 123 * to remove some code which would otherwise be called on each allocation by 124 * utilizing a known, stable state. This differs from the constructor which 125 * will be called on EVERY allocation. 126 * 127 * For example, in the initializer you may want to initialize embeded locks, 128 * NULL list pointers, set up initial states, magic numbers, etc. This way if 129 * the object is held in the allocator and re-used it won't be necessary to 130 * re-initialize it. 131 * 132 * The constructor may be used to lock a data structure, link it on to lists, 133 * bump reference counts or total counts of outstanding structures, etc. 134 * 135 */ 136 137 138 /* Function proto types */ 139 140 /* 141 * Create a new uma zone 142 * 143 * Arguments: 144 * name The text name of the zone for debugging and stats, this memory 145 * should not be freed until the zone has been deallocated. 146 * size The size of the object that is being created. 147 * ctor The constructor that is called when the object is allocated 148 * dtor The destructor that is called when the object is freed. 149 * init An initializer that sets up the initial state of the memory. 150 * fini A discard function that undoes initialization done by init. 151 * ctor/dtor/init/fini may all be null, see notes above. 152 * align A bitmask that corisponds to the requested alignment 153 * eg 4 would be 0x3 154 * flags A set of parameters that control the behavior of the zone 155 * 156 * Returns: 157 * A pointer to a structure which is intended to be opaque to users of 158 * the interface. The value may be null if the wait flag is not set. 159 */ 160 161 uma_zone_t uma_zcreate(char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 162 uma_init uminit, uma_fini fini, int align, 163 u_int16_t flags); 164 165 /* 166 * Definitions for uma_zcreate flags 167 * 168 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to 169 * overlap when adding new features. 0xf000 is in use by uma_int.h. 170 */ 171 #define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by 172 physical memory XXX Not yet */ 173 #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */ 174 #define UMA_ZONE_STATIC 0x0004 /* Staticly sized zone */ 175 #define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation 176 off of the real memory */ 177 #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */ 178 #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */ 179 #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */ 180 #define UMA_ZONE_VM 0x0080 /* 181 * Used for internal vm datastructures 182 * only. 183 */ 184 #define UMA_ZONE_HASH 0x0100 /* 185 * Use a hash table instead of caching 186 * information in the vm_page. 187 */ 188 189 /* Definitions for align */ 190 #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */ 191 #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */ 192 #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */ 193 #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */ 194 #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */ 195 #define UMA_ALIGN_CACHE (16 - 1) /* Cache line size align */ 196 197 /* 198 * Destroys an empty uma zone. If the zone is not empty uma complains loudly. 199 * 200 * Arguments: 201 * zone The zone we want to destroy. 202 * 203 */ 204 205 void uma_zdestroy(uma_zone_t zone); 206 207 /* 208 * Allocates an item out of a zone 209 * 210 * Arguments: 211 * zone The zone we are allocating from 212 * arg This data is passed to the ctor function 213 * flags See sys/malloc.h for available flags. 214 * 215 * Returns: 216 * A non null pointer to an initialized element from the zone is 217 * garanteed if the wait flag is M_WAITOK, otherwise a null pointer may be 218 * returned if the zone is empty or the ctor failed. 219 */ 220 221 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags); 222 223 /* 224 * Allocates an item out of a zone without supplying an argument 225 * 226 * This is just a wrapper for uma_zalloc_arg for convenience. 227 * 228 */ 229 static __inline void *uma_zalloc(uma_zone_t zone, int flags); 230 231 static __inline void * 232 uma_zalloc(uma_zone_t zone, int flags) 233 { 234 return uma_zalloc_arg(zone, NULL, flags); 235 } 236 237 /* 238 * Frees an item back into the specified zone. 239 * 240 * Arguments: 241 * zone The zone the item was originally allocated out of. 242 * item The memory to be freed. 243 * arg Argument passed to the destructor 244 * 245 * Returns: 246 * Nothing. 247 */ 248 249 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg); 250 251 /* 252 * Frees an item back to a zone without supplying an argument 253 * 254 * This is just a wrapper for uma_zfree_arg for convenience. 255 * 256 */ 257 static __inline void uma_zfree(uma_zone_t zone, void *item); 258 259 static __inline void 260 uma_zfree(uma_zone_t zone, void *item) 261 { 262 uma_zfree_arg(zone, item, NULL); 263 } 264 265 /* 266 * XXX The rest of the prototypes in this header are h0h0 magic for the VM. 267 * If you think you need to use it for a normal zone you're probably incorrect. 268 */ 269 270 /* 271 * Backend page supplier routines 272 * 273 * Arguments: 274 * zone The zone that is requesting pages 275 * size The number of bytes being requested 276 * pflag Flags for these memory pages, see below. 277 * wait Indicates our willingness to block. 278 * 279 * Returns: 280 * A pointer to the alloced memory or NULL on failure. 281 */ 282 283 typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait); 284 285 /* 286 * Backend page free routines 287 * 288 * Arguments: 289 * item A pointer to the previously allocated pages 290 * size The original size of the allocation 291 * pflag The flags for the slab. See UMA_SLAB_* below 292 * 293 * Returns: 294 * None 295 */ 296 typedef void (*uma_free)(void *item, int size, u_int8_t pflag); 297 298 299 300 /* 301 * Sets up the uma allocator. (Called by vm_mem_init) 302 * 303 * Arguments: 304 * bootmem A pointer to memory used to bootstrap the system. 305 * 306 * Returns: 307 * Nothing 308 * 309 * Discussion: 310 * This memory is used for zones which allocate things before the 311 * backend page supplier can give us pages. It should be 312 * UMA_SLAB_SIZE * UMA_BOOT_PAGES bytes. (see uma_int.h) 313 * 314 */ 315 316 void uma_startup(void *bootmem); 317 318 /* 319 * Finishes starting up the allocator. This should 320 * be called when kva is ready for normal allocs. 321 * 322 * Arguments: 323 * None 324 * 325 * Returns: 326 * Nothing 327 * 328 * Discussion: 329 * uma_startup2 is called by kmeminit() to enable us of uma for malloc. 330 */ 331 332 void uma_startup2(void); 333 334 /* 335 * Reclaims unused memory for all zones 336 * 337 * Arguments: 338 * None 339 * Returns: 340 * None 341 * 342 * This should only be called by the page out daemon. 343 */ 344 345 void uma_reclaim(void); 346 347 /* 348 * Switches the backing object of a zone 349 * 350 * Arguments: 351 * zone The zone to update 352 * obj The obj to use for future allocations 353 * size The size of the object to allocate 354 * 355 * Returns: 356 * 0 if kva space can not be allocated 357 * 1 if successful 358 * 359 * Discussion: 360 * A NULL object can be used and uma will allocate one for you. Setting 361 * the size will limit the amount of memory allocated to this zone. 362 * 363 */ 364 struct vm_object; 365 int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size); 366 367 /* 368 * Sets a high limit on the number of items allowed in a zone 369 * 370 * Arguments: 371 * zone The zone to limit 372 * 373 * Returns: 374 * Nothing 375 */ 376 void uma_zone_set_max(uma_zone_t zone, int nitems); 377 378 /* 379 * Replaces the standard page_alloc or obj_alloc functions for this zone 380 * 381 * Arguments: 382 * zone The zone whos back end allocator is being changed. 383 * allocf A pointer to the allocation function 384 * 385 * Returns: 386 * Nothing 387 * 388 * Discussion: 389 * This could be used to implement pageable allocation, or perhaps 390 * even DMA allocators if used in conjunction with the OFFPAGE 391 * zone flag. 392 */ 393 394 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf); 395 396 /* 397 * Used for freeing memory provided by the allocf above 398 * 399 * Arguments: 400 * zone The zone that intends to use this free routine. 401 * freef The page freeing routine. 402 * 403 * Returns: 404 * Nothing 405 */ 406 407 void uma_zone_set_freef(uma_zone_t zone, uma_free freef); 408 409 /* 410 * These flags are setable in the allocf and visable in the freef. 411 */ 412 #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */ 413 #define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */ 414 #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */ 415 #define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */ 416 #define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */ 417 /* 0x40 and 0x80 are available */ 418 419 /* 420 * Used to pre-fill a zone with some number of items 421 * 422 * Arguments: 423 * zone The zone to fill 424 * itemcnt The number of items to reserve 425 * 426 * Returns: 427 * Nothing 428 * 429 * NOTE: This is blocking and should only be done at startup 430 */ 431 void uma_prealloc(uma_zone_t zone, int itemcnt); 432 433 434 #endif 435