137 lines
5.2 KiB
C
137 lines
5.2 KiB
C
/*-
|
|
* Copyright (c) 1991, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* from: @(#)mpool.h 8.1 (Berkeley) 6/2/93
|
|
* $Id: mpool.h,v 1.4 1993/08/01 18:44:47 mycroft Exp $
|
|
*/
|
|
|
|
/*
|
|
* The memory pool scheme is a simple one. Each in memory page is referenced
|
|
* by a bucket which is threaded in three ways. All active pages are threaded
|
|
* on a hash chain (hashed by the page number) and an lru chain. Inactive
|
|
* pages are threaded on a free chain. Each reference to a memory pool is
|
|
* handed an MPOOL which is the opaque cookie passed to all of the memory
|
|
* routines.
|
|
*/
|
|
#define HASHSIZE 128
|
|
#define HASHKEY(pgno) ((pgno - 1) % HASHSIZE)
|
|
|
|
/* The BKT structures are the elements of the lists. */
|
|
typedef struct BKT {
|
|
struct BKT *hnext; /* next hash bucket */
|
|
struct BKT *hprev; /* previous hash bucket */
|
|
struct BKT *cnext; /* next free/lru bucket */
|
|
struct BKT *cprev; /* previous free/lru bucket */
|
|
void *page; /* page */
|
|
pgno_t pgno; /* page number */
|
|
|
|
#define MPOOL_DIRTY 0x01 /* page needs to be written */
|
|
#define MPOOL_PINNED 0x02 /* page is pinned into memory */
|
|
unsigned long flags; /* flags */
|
|
} BKT;
|
|
|
|
/* The BKTHDR structures are the heads of the lists. */
|
|
typedef struct BKTHDR {
|
|
struct BKT *hnext; /* next hash bucket */
|
|
struct BKT *hprev; /* previous hash bucket */
|
|
struct BKT *cnext; /* next free/lru bucket */
|
|
struct BKT *cprev; /* previous free/lru bucket */
|
|
} BKTHDR;
|
|
|
|
typedef struct MPOOL {
|
|
BKTHDR free; /* The free list. */
|
|
BKTHDR lru; /* The LRU list. */
|
|
BKTHDR hashtable[HASHSIZE]; /* Hashed list by page number. */
|
|
pgno_t curcache; /* Current number of cached pages. */
|
|
pgno_t maxcache; /* Max number of cached pages. */
|
|
pgno_t npages; /* Number of pages in the file. */
|
|
u_long pagesize; /* File page size. */
|
|
int fd; /* File descriptor. */
|
|
/* Page in conversion routine. */
|
|
void (*pgin) __P((void *, pgno_t, void *));
|
|
/* Page out conversion routine. */
|
|
void (*pgout) __P((void *, pgno_t, void *));
|
|
void *pgcookie; /* Cookie for page in/out routines. */
|
|
#ifdef STATISTICS
|
|
unsigned long cachehit;
|
|
unsigned long cachemiss;
|
|
unsigned long pagealloc;
|
|
unsigned long pageflush;
|
|
unsigned long pageget;
|
|
unsigned long pagenew;
|
|
unsigned long pageput;
|
|
unsigned long pageread;
|
|
unsigned long pagewrite;
|
|
#endif
|
|
} MPOOL;
|
|
|
|
#ifdef __MPOOLINTERFACE_PRIVATE
|
|
/* Macros to insert/delete into/from hash chain. */
|
|
#define rmhash(bp) { \
|
|
(bp)->hprev->hnext = (bp)->hnext; \
|
|
(bp)->hnext->hprev = (bp)->hprev; \
|
|
}
|
|
#define inshash(bp, pg) { \
|
|
hp = &mp->hashtable[HASHKEY(pg)]; \
|
|
(bp)->hnext = hp->hnext; \
|
|
(bp)->hprev = (struct BKT *)hp; \
|
|
hp->hnext->hprev = (bp); \
|
|
hp->hnext = (bp); \
|
|
}
|
|
|
|
/* Macros to insert/delete into/from lru and free chains. */
|
|
#define rmchain(bp) { \
|
|
(bp)->cprev->cnext = (bp)->cnext; \
|
|
(bp)->cnext->cprev = (bp)->cprev; \
|
|
}
|
|
#define inschain(bp, dp) { \
|
|
(bp)->cnext = (dp)->cnext; \
|
|
(bp)->cprev = (struct BKT *)(dp); \
|
|
(dp)->cnext->cprev = (bp); \
|
|
(dp)->cnext = (bp); \
|
|
}
|
|
#endif
|
|
|
|
__BEGIN_DECLS
|
|
MPOOL *mpool_open __P((DBT *, int, pgno_t, pgno_t));
|
|
void mpool_filter __P((MPOOL *, void (*)(void *, pgno_t, void *),
|
|
void (*)(void *, pgno_t, void *), void *));
|
|
void *mpool_new __P((MPOOL *, pgno_t *));
|
|
void *mpool_get __P((MPOOL *, pgno_t, u_int));
|
|
int mpool_put __P((MPOOL *, void *, u_int));
|
|
int mpool_sync __P((MPOOL *));
|
|
int mpool_close __P((MPOOL *));
|
|
#ifdef STATISTICS
|
|
void mpool_stat __P((MPOOL *));
|
|
#endif
|
|
__END_DECLS
|