1 /*- 2 * Copyright (c) 2004, 2005 3 * Bosko Milekic <bmilekic@freebsd.org> 4 * Copyright (c) 2002, 2003, 2004, 2005, 5 * Jeffrey Roberson <jeff@freebsd.org> 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 unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 * 30 */ 31 32 /* 33 * uma.h - External definitions for the Universal Memory Allocator 34 * 35 */ 36 37 #ifndef VM_UMA_H 38 #define VM_UMA_H 39 40 #include <sys/param.h> /* For NULL */ 41 #include <sys/malloc.h> /* For M_* */ 42 43 /* User visable parameters */ 44 #define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */ 45 46 /* Types and type defs */ 47 48 struct uma_zone; 49 /* Opaque type used as a handle to the zone */ 50 typedef struct uma_zone * uma_zone_t; 51 52 /* 53 * Item constructor 54 * 55 * Arguments: 56 * item A pointer to the memory which has been allocated. 57 * arg The arg field passed to uma_zalloc_arg 58 * size The size of the allocated item 59 * flags See zalloc flags 60 * 61 * Returns: 62 * 0 on success 63 * errno on failure 64 * 65 * Discussion: 66 * The constructor is called just before the memory is returned 67 * to the user. It may block if necessary. 68 */ 69 typedef int (*uma_ctor)(void *mem, int size, void *arg, int flags); 70 71 /* 72 * Item destructor 73 * 74 * Arguments: 75 * item A pointer to the memory which has been allocated. 76 * size The size of the item being destructed. 77 * arg Argument passed through uma_zfree_arg 78 * 79 * Returns: 80 * Nothing 81 * 82 * Discussion: 83 * The destructor may perform operations that differ from those performed 84 * by the initializer, but it must leave the object in the same state. 85 * This IS type stable storage. This is called after EVERY zfree call. 86 */ 87 typedef void (*uma_dtor)(void *mem, int size, void *arg); 88 89 /* 90 * Item initializer 91 * 92 * Arguments: 93 * item A pointer to the memory which has been allocated. 94 * size The size of the item being initialized. 95 * flags See zalloc flags 96 * 97 * Returns: 98 * 0 on success 99 * errno on failure 100 * 101 * Discussion: 102 * The initializer is called when the memory is cached in the uma zone. 103 * this should be the same state that the destructor leaves the object in. 104 */ 105 typedef int (*uma_init)(void *mem, int size, int flags); 106 107 /* 108 * Item discard function 109 * 110 * Arguments: 111 * item A pointer to memory which has been 'freed' but has not left the 112 * zone's cache. 113 * size The size of the item being discarded. 114 * 115 * Returns: 116 * Nothing 117 * 118 * Discussion: 119 * This routine is called when memory leaves a zone and is returned to the 120 * system for other uses. It is the counter part to the init function. 121 */ 122 typedef void (*uma_fini)(void *mem, int size); 123 124 /* 125 * What's the difference between initializing and constructing? 126 * 127 * The item is initialized when it is cached, and this is the state that the 128 * object should be in when returned to the allocator. The purpose of this is 129 * to remove some code which would otherwise be called on each allocation by 130 * utilizing a known, stable state. This differs from the constructor which 131 * will be called on EVERY allocation. 132 * 133 * For example, in the initializer you may want to initialize embeded locks, 134 * NULL list pointers, set up initial states, magic numbers, etc. This way if 135 * the object is held in the allocator and re-used it won't be necessary to 136 * re-initialize it. 137 * 138 * The constructor may be used to lock a data structure, link it on to lists, 139 * bump reference counts or total counts of outstanding structures, etc. 140 * 141 */ 142 143 144 /* Function proto types */ 145 146 /* 147 * Create a new uma zone 148 * 149 * Arguments: 150 * name The text name of the zone for debugging and stats, this memory 151 * should not be freed until the zone has been deallocated. 152 * size The size of the object that is being created. 153 * ctor The constructor that is called when the object is allocated 154 * dtor The destructor that is called when the object is freed. 155 * init An initializer that sets up the initial state of the memory. 156 * fini A discard function that undoes initialization done by init. 157 * ctor/dtor/init/fini may all be null, see notes above. 158 * align A bitmask that corisponds to the requested alignment 159 * eg 4 would be 0x3 160 * flags A set of parameters that control the behavior of the zone 161 * 162 * Returns: 163 * A pointer to a structure which is intended to be opaque to users of 164 * the interface. The value may be null if the wait flag is not set. 165 */ 166 uma_zone_t uma_zcreate(char *name, size_t size, uma_ctor ctor, uma_dtor dtor, 167 uma_init uminit, uma_fini fini, int align, 168 u_int16_t flags); 169 170 /* 171 * Create a secondary uma zone 172 * 173 * Arguments: 174 * name The text name of the zone for debugging and stats, this memory 175 * should not be freed until the zone has been deallocated. 176 * ctor The constructor that is called when the object is allocated 177 * dtor The destructor that is called when the object is freed. 178 * zinit An initializer that sets up the initial state of the memory 179 * as the object passes from the Keg's slab to the Zone's cache. 180 * zfini A discard function that undoes initialization done by init 181 * as the object passes from the Zone's cache to the Keg's slab. 182 * 183 * ctor/dtor/zinit/zfini may all be null, see notes above. 184 * Note that the zinit and zfini specified here are NOT 185 * exactly the same as the init/fini specified to uma_zcreate() 186 * when creating a master zone. These zinit/zfini are called 187 * on the TRANSITION from keg to zone (and vice-versa). Once 188 * these are set, the primary zone may alter its init/fini 189 * (which are called when the object passes from VM to keg) 190 * using uma_zone_set_init/fini()) as well as its own 191 * zinit/zfini (unset by default for master zone) with 192 * uma_zone_set_zinit/zfini() (note subtle 'z' prefix). 193 * 194 * master A reference to this zone's Master Zone (Primary Zone), 195 * which contains the backing Keg for the Secondary Zone 196 * being added. 197 * 198 * Returns: 199 * A pointer to a structure which is intended to be opaque to users of 200 * the interface. The value may be null if the wait flag is not set. 201 */ 202 uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor, 203 uma_init zinit, uma_fini zfini, uma_zone_t master); 204 205 /* 206 * Definitions for uma_zcreate flags 207 * 208 * These flags share space with UMA_ZFLAGs in uma_int.h. Be careful not to 209 * overlap when adding new features. 0xf000 is in use by uma_int.h. 210 */ 211 #define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by 212 physical memory XXX Not yet */ 213 #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */ 214 #define UMA_ZONE_STATIC 0x0004 /* Staticly sized zone */ 215 #define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation 216 off of the real memory */ 217 #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */ 218 #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */ 219 #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */ 220 #define UMA_ZONE_VM 0x0080 /* 221 * Used for internal vm datastructures 222 * only. 223 */ 224 #define UMA_ZONE_HASH 0x0100 /* 225 * Use a hash table instead of caching 226 * information in the vm_page. 227 */ 228 #define UMA_ZONE_SECONDARY 0x0200 /* Zone is a Secondary Zone */ 229 #define UMA_ZONE_REFCNT 0x0400 /* Allocate refcnts in slabs */ 230 #define UMA_ZONE_MAXBUCKET 0x0800 /* Use largest buckets */ 231 232 /* Definitions for align */ 233 #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */ 234 #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */ 235 #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */ 236 #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */ 237 #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */ 238 #define UMA_ALIGN_CACHE (16 - 1) /* Cache line size align */ 239 240 /* 241 * Destroys an empty uma zone. If the zone is not empty uma complains loudly. 242 * 243 * Arguments: 244 * zone The zone we want to destroy. 245 * 246 */ 247 void uma_zdestroy(uma_zone_t zone); 248 249 /* 250 * Allocates an item out of a zone 251 * 252 * Arguments: 253 * zone The zone we are allocating from 254 * arg This data is passed to the ctor function 255 * flags See sys/malloc.h for available flags. 256 * 257 * Returns: 258 * A non null pointer to an initialized element from the zone is 259 * garanteed if the wait flag is M_WAITOK, otherwise a null pointer may be 260 * returned if the zone is empty or the ctor failed. 261 */ 262 263 void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags); 264 265 /* 266 * Allocates an item out of a zone without supplying an argument 267 * 268 * This is just a wrapper for uma_zalloc_arg for convenience. 269 * 270 */ 271 static __inline void *uma_zalloc(uma_zone_t zone, int flags); 272 273 static __inline void * 274 uma_zalloc(uma_zone_t zone, int flags) 275 { 276 return uma_zalloc_arg(zone, NULL, flags); 277 } 278 279 /* 280 * Frees an item back into the specified zone. 281 * 282 * Arguments: 283 * zone The zone the item was originally allocated out of. 284 * item The memory to be freed. 285 * arg Argument passed to the destructor 286 * 287 * Returns: 288 * Nothing. 289 */ 290 291 void uma_zfree_arg(uma_zone_t zone, void *item, void *arg); 292 293 /* 294 * Frees an item back to a zone without supplying an argument 295 * 296 * This is just a wrapper for uma_zfree_arg for convenience. 297 * 298 */ 299 static __inline void uma_zfree(uma_zone_t zone, void *item); 300 301 static __inline void 302 uma_zfree(uma_zone_t zone, void *item) 303 { 304 uma_zfree_arg(zone, item, NULL); 305 } 306 307 /* 308 * XXX The rest of the prototypes in this header are h0h0 magic for the VM. 309 * If you think you need to use it for a normal zone you're probably incorrect. 310 */ 311 312 /* 313 * Backend page supplier routines 314 * 315 * Arguments: 316 * zone The zone that is requesting pages 317 * size The number of bytes being requested 318 * pflag Flags for these memory pages, see below. 319 * wait Indicates our willingness to block. 320 * 321 * Returns: 322 * A pointer to the alloced memory or NULL on failure. 323 */ 324 325 typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait); 326 327 /* 328 * Backend page free routines 329 * 330 * Arguments: 331 * item A pointer to the previously allocated pages 332 * size The original size of the allocation 333 * pflag The flags for the slab. See UMA_SLAB_* below 334 * 335 * Returns: 336 * None 337 */ 338 typedef void (*uma_free)(void *item, int size, u_int8_t pflag); 339 340 341 342 /* 343 * Sets up the uma allocator. (Called by vm_mem_init) 344 * 345 * Arguments: 346 * bootmem A pointer to memory used to bootstrap the system. 347 * 348 * Returns: 349 * Nothing 350 * 351 * Discussion: 352 * This memory is used for zones which allocate things before the 353 * backend page supplier can give us pages. It should be 354 * UMA_SLAB_SIZE * UMA_BOOT_PAGES bytes. (see uma_int.h) 355 * 356 */ 357 358 void uma_startup(void *bootmem); 359 360 /* 361 * Finishes starting up the allocator. This should 362 * be called when kva is ready for normal allocs. 363 * 364 * Arguments: 365 * None 366 * 367 * Returns: 368 * Nothing 369 * 370 * Discussion: 371 * uma_startup2 is called by kmeminit() to enable us of uma for malloc. 372 */ 373 374 void uma_startup2(void); 375 376 /* 377 * Reclaims unused memory for all zones 378 * 379 * Arguments: 380 * None 381 * Returns: 382 * None 383 * 384 * This should only be called by the page out daemon. 385 */ 386 387 void uma_reclaim(void); 388 389 /* 390 * Switches the backing object of a zone 391 * 392 * Arguments: 393 * zone The zone to update 394 * obj The obj to use for future allocations 395 * size The size of the object to allocate 396 * 397 * Returns: 398 * 0 if kva space can not be allocated 399 * 1 if successful 400 * 401 * Discussion: 402 * A NULL object can be used and uma will allocate one for you. Setting 403 * the size will limit the amount of memory allocated to this zone. 404 * 405 */ 406 struct vm_object; 407 int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size); 408 409 /* 410 * Sets a high limit on the number of items allowed in a zone 411 * 412 * Arguments: 413 * zone The zone to limit 414 * 415 * Returns: 416 * Nothing 417 */ 418 void uma_zone_set_max(uma_zone_t zone, int nitems); 419 420 /* 421 * The following two routines (uma_zone_set_init/fini) 422 * are used to set the backend init/fini pair which acts on an 423 * object as it becomes allocated and is placed in a slab within 424 * the specified zone's backing keg. These should probably not 425 * be changed once allocations have already begun and only 426 * immediately upon zone creation. 427 */ 428 void uma_zone_set_init(uma_zone_t zone, uma_init uminit); 429 void uma_zone_set_fini(uma_zone_t zone, uma_fini fini); 430 431 /* 432 * The following two routines (uma_zone_set_zinit/zfini) are 433 * used to set the zinit/zfini pair which acts on an object as 434 * it passes from the backing Keg's slab cache to the 435 * specified Zone's bucket cache. These should probably not 436 * be changed once allocations have already begun and 437 * only immediately upon zone creation. 438 */ 439 void uma_zone_set_zinit(uma_zone_t zone, uma_init zinit); 440 void uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini); 441 442 /* 443 * Replaces the standard page_alloc or obj_alloc functions for this zone 444 * 445 * Arguments: 446 * zone The zone whos back end allocator is being changed. 447 * allocf A pointer to the allocation function 448 * 449 * Returns: 450 * Nothing 451 * 452 * Discussion: 453 * This could be used to implement pageable allocation, or perhaps 454 * even DMA allocators if used in conjunction with the OFFPAGE 455 * zone flag. 456 */ 457 458 void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf); 459 460 /* 461 * Used for freeing memory provided by the allocf above 462 * 463 * Arguments: 464 * zone The zone that intends to use this free routine. 465 * freef The page freeing routine. 466 * 467 * Returns: 468 * Nothing 469 */ 470 471 void uma_zone_set_freef(uma_zone_t zone, uma_free freef); 472 473 /* 474 * These flags are setable in the allocf and visable in the freef. 475 */ 476 #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */ 477 #define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */ 478 #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */ 479 #define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */ 480 #define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */ 481 /* 0x40 and 0x80 are available */ 482 483 /* 484 * Used to pre-fill a zone with some number of items 485 * 486 * Arguments: 487 * zone The zone to fill 488 * itemcnt The number of items to reserve 489 * 490 * Returns: 491 * Nothing 492 * 493 * NOTE: This is blocking and should only be done at startup 494 */ 495 void uma_prealloc(uma_zone_t zone, int itemcnt); 496 497 /* 498 * Used to lookup the reference counter allocated for an item 499 * from a UMA_ZONE_REFCNT zone. For UMA_ZONE_REFCNT zones, 500 * reference counters are allocated for items and stored in 501 * the underlying slab header. 502 * 503 * Arguments: 504 * zone The UMA_ZONE_REFCNT zone to which the item belongs. 505 * item The address of the item for which we want a refcnt. 506 * 507 * Returns: 508 * A pointer to a u_int32_t reference counter. 509 */ 510 u_int32_t *uma_find_refcnt(uma_zone_t zone, void *item); 511 512 #endif 513