159deaec5SRodney W. Grimes /*- 290fd5bdfSPaul Traina * Copyright (c) 1991, 1993, 1994 359deaec5SRodney W. Grimes * The Regents of the University of California. All rights reserved. 459deaec5SRodney W. Grimes * 559deaec5SRodney W. Grimes * Redistribution and use in source and binary forms, with or without 659deaec5SRodney W. Grimes * modification, are permitted provided that the following conditions 759deaec5SRodney W. Grimes * are met: 859deaec5SRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 959deaec5SRodney W. Grimes * notice, this list of conditions and the following disclaimer. 1059deaec5SRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 1159deaec5SRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 1259deaec5SRodney W. Grimes * documentation and/or other materials provided with the distribution. 13f2556687SWarner Losh * 3. Neither the name of the University nor the names of its contributors 1459deaec5SRodney W. Grimes * may be used to endorse or promote products derived from this software 1559deaec5SRodney W. Grimes * without specific prior written permission. 1659deaec5SRodney W. Grimes * 1759deaec5SRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 1859deaec5SRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1959deaec5SRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2059deaec5SRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2159deaec5SRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2259deaec5SRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2359deaec5SRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2459deaec5SRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2559deaec5SRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2659deaec5SRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2759deaec5SRodney W. Grimes * SUCH DAMAGE. 2859deaec5SRodney W. Grimes * 299fc74a87SXin LI * @(#)mpool.h 8.4 (Berkeley) 11/2/95 30740a1973SJake Burkholder * $FreeBSD$ 3159deaec5SRodney W. Grimes */ 3259deaec5SRodney W. Grimes 3354b0ee63SPaul Richards #ifndef _MPOOL_H_ 3454b0ee63SPaul Richards #define _MPOOL_H_ 3554b0ee63SPaul Richards 3690fd5bdfSPaul Traina #include <sys/queue.h> 3790fd5bdfSPaul Traina 3859deaec5SRodney W. Grimes /* 3990fd5bdfSPaul Traina * The memory pool scheme is a simple one. Each in-memory page is referenced 4090fd5bdfSPaul Traina * by a bucket which is threaded in up to two of three ways. All active pages 4190fd5bdfSPaul Traina * are threaded on a hash chain (hashed by page number) and an lru chain. 4290fd5bdfSPaul Traina * Inactive pages are threaded on a free chain. Each reference to a memory 4390fd5bdfSPaul Traina * pool is handed an opaque MPOOL cookie which stores all of this information. 4459deaec5SRodney W. Grimes */ 4559deaec5SRodney W. Grimes #define HASHSIZE 128 469fc74a87SXin LI #define HASHKEY(pgno) ((pgno - 1 + HASHSIZE) % HASHSIZE) 4759deaec5SRodney W. Grimes 4890fd5bdfSPaul Traina /* The BKT structures are the elements of the queues. */ 4990fd5bdfSPaul Traina typedef struct _bkt { 50fabacd3aSPoul-Henning Kamp TAILQ_ENTRY(_bkt) hq; /* hash queue */ 51fabacd3aSPoul-Henning Kamp TAILQ_ENTRY(_bkt) q; /* lru queue */ 5259deaec5SRodney W. Grimes void *page; /* page */ 5359deaec5SRodney W. Grimes pgno_t pgno; /* page number */ 5459deaec5SRodney W. Grimes 5559deaec5SRodney W. Grimes #define MPOOL_DIRTY 0x01 /* page needs to be written */ 5659deaec5SRodney W. Grimes #define MPOOL_PINNED 0x02 /* page is pinned into memory */ 579fc74a87SXin LI #define MPOOL_INUSE 0x04 /* page address is valid */ 5890fd5bdfSPaul Traina u_int8_t flags; /* flags */ 5959deaec5SRodney W. Grimes } BKT; 6059deaec5SRodney W. Grimes 6159deaec5SRodney W. Grimes typedef struct MPOOL { 62fabacd3aSPoul-Henning Kamp TAILQ_HEAD(_lqh, _bkt) lqh; /* lru queue head */ 6390fd5bdfSPaul Traina /* hash queue array */ 64fabacd3aSPoul-Henning Kamp TAILQ_HEAD(_hqh, _bkt) hqh[HASHSIZE]; 6590fd5bdfSPaul Traina pgno_t curcache; /* current number of cached pages */ 6690fd5bdfSPaul Traina pgno_t maxcache; /* max number of cached pages */ 6790fd5bdfSPaul Traina pgno_t npages; /* number of pages in the file */ 689fc74a87SXin LI unsigned long pagesize; /* file page size */ 6990fd5bdfSPaul Traina int fd; /* file descriptor */ 7090fd5bdfSPaul Traina /* page in conversion routine */ 71bb28f3c2SWarner Losh void (*pgin)(void *, pgno_t, void *); 7290fd5bdfSPaul Traina /* page out conversion routine */ 73bb28f3c2SWarner Losh void (*pgout)(void *, pgno_t, void *); 7490fd5bdfSPaul Traina void *pgcookie; /* cookie for page in/out routines */ 7559deaec5SRodney W. Grimes #ifdef STATISTICS 769fc74a87SXin LI unsigned long cachehit; 779fc74a87SXin LI unsigned long cachemiss; 789fc74a87SXin LI unsigned long pagealloc; 799fc74a87SXin LI unsigned long pageflush; 809fc74a87SXin LI unsigned long pageget; 819fc74a87SXin LI unsigned long pagenew; 829fc74a87SXin LI unsigned long pageput; 839fc74a87SXin LI unsigned long pageread; 849fc74a87SXin LI unsigned long pagewrite; 8559deaec5SRodney W. Grimes #endif 8659deaec5SRodney W. Grimes } MPOOL; 8759deaec5SRodney W. Grimes 889fc74a87SXin LI #define MPOOL_IGNOREPIN 0x01 /* Ignore if the page is pinned. */ 899fc74a87SXin LI #define MPOOL_PAGE_REQUEST 0x01 /* Allocate a new page with a 909fc74a87SXin LI specific page number. */ 919fc74a87SXin LI #define MPOOL_PAGE_NEXT 0x02 /* Allocate a new page with the next 929fc74a87SXin LI page number. */ 939fc74a87SXin LI 9459deaec5SRodney W. Grimes __BEGIN_DECLS 95bb28f3c2SWarner Losh MPOOL *mpool_open(void *, int, pgno_t, pgno_t); 96bb28f3c2SWarner Losh void mpool_filter(MPOOL *, void (*)(void *, pgno_t, void *), 97bb28f3c2SWarner Losh void (*)(void *, pgno_t, void *), void *); 989fc74a87SXin LI void *mpool_new(MPOOL *, pgno_t *, unsigned int); 999fc74a87SXin LI void *mpool_get(MPOOL *, pgno_t, unsigned int); 1009fc74a87SXin LI int mpool_delete(MPOOL *, void *); 1019fc74a87SXin LI int mpool_put(MPOOL *, void *, unsigned int); 102bb28f3c2SWarner Losh int mpool_sync(MPOOL *); 103bb28f3c2SWarner Losh int mpool_close(MPOOL *); 10459deaec5SRodney W. Grimes #ifdef STATISTICS 105bb28f3c2SWarner Losh void mpool_stat(MPOOL *); 10659deaec5SRodney W. Grimes #endif 10759deaec5SRodney W. Grimes __END_DECLS 10854b0ee63SPaul Richards 10954b0ee63SPaul Richards #endif 110