1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 #ifndef _KRB5_DB2_MPOOL_MPOOL_H
7 #define	_KRB5_DB2_MPOOL_MPOOL_H
8 
9 #ifdef	__cplusplus
10 extern "C" {
11 #endif
12 
13 /*
14  * Copyright (c) 1991, 1993, 1994
15  *	The Regents of the University of California.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  * 3. All advertising materials mentioning features or use of this software
26  *    must display the following acknowledgement:
27  *	This product includes software developed by the University of
28  *	California, Berkeley and its contributors.
29  * 4. Neither the name of the University nor the names of its contributors
30  *    may be used to endorse or promote products derived from this software
31  *    without specific prior written permission.
32  *
33  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
34  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
37  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43  * SUCH DAMAGE.
44  *
45  *	@(#)mpool.h	8.4 (Berkeley) 11/2/95
46  */
47 
48 #include "db-queue.h"
49 
50 /*
51  * The memory pool scheme is a simple one.  Each in-memory page is referenced
52  * by a bucket which is threaded in up to two of three ways.  All active pages
53  * are threaded on a hash chain (hashed by page number) and an lru chain.
54  * Inactive pages are threaded on a free chain.  Each reference to a memory
55  * pool is handed an opaque MPOOL cookie which stores all of this information.
56  */
57 #define	HASHSIZE	128
58 #define	HASHKEY(pgno)	((pgno - 1) % HASHSIZE)
59 
60 /* The BKT structures are the elements of the queues. */
61 typedef struct _bkt {
62 	CIRCLEQ_ENTRY(_bkt) hq;		/* hash queue */
63 	CIRCLEQ_ENTRY(_bkt) q;		/* lru queue */
64 	void    *page;			/* page */
65 	db_pgno_t   pgno;			/* page number */
66 
67 #define	MPOOL_DIRTY	0x01		/* page needs to be written */
68 #define	MPOOL_PINNED	0x02		/* page is pinned into memory */
69 #define	MPOOL_INUSE	0x04		/* page address is valid */
70 	u_int8_t flags;			/* flags */
71 } BKT;
72 
73 typedef struct MPOOL {
74 	CIRCLEQ_HEAD(_lqh, _bkt) lqh;	/* lru queue head */
75 					/* hash queue array */
76 	CIRCLEQ_HEAD(_hqh, _bkt) hqh[HASHSIZE];
77 	db_pgno_t	curcache;		/* current number of cached pages */
78 	db_pgno_t	maxcache;		/* max number of cached pages */
79 	db_pgno_t	npages;			/* number of pages in the file */
80 	u_long	pagesize;		/* file page size */
81 	int	fd;			/* file descriptor */
82 					/* page in conversion routine */
83 	void    (*pgin) __P((void *, db_pgno_t, void *));
84 					/* page out conversion routine */
85 	void    (*pgout) __P((void *, db_pgno_t, void *));
86 	void	*pgcookie;		/* cookie for page in/out routines */
87 #ifdef STATISTICS
88 	u_long	cachehit;
89 	u_long	cachemiss;
90 	u_long	pagealloc;
91 	u_long	pageflush;
92 	u_long	pageget;
93 	u_long	pagenew;
94 	u_long	pageput;
95 	u_long	pageread;
96 	u_long	pagewrite;
97 #endif
98 } MPOOL;
99 
100 #define	MPOOL_IGNOREPIN	0x01		/* Ignore if the page is pinned. */
101 #define	MPOOL_PAGE_REQUEST	0x01	/* Allocate a new page with a
102 					   specific page number. */
103 #define	MPOOL_PAGE_NEXT		0x02	/* Allocate a new page with the next
104 					  page number. */
105 
106 #define mpool_open	kdb2_mpool_open
107 #define mpool_filter	kdb2_mpool_filter
108 #define mpool_new	kdb2_mpool_new
109 #define mpool_get	kdb2_mpool_get
110 #define mpool_delete	kdb2_mpool_delete
111 #define mpool_put	kdb2_mpool_put
112 #define mpool_sync	kdb2_mpool_sync
113 #define mpool_close	kdb2_mpool_close
114 #define mpool_stat	kdb2_mpool_stat
115 
116 __BEGIN_DECLS
117 MPOOL	*mpool_open __P((void *, int, db_pgno_t, db_pgno_t));
118 void	 mpool_filter __P((MPOOL *, void (*)(void *, db_pgno_t, void *),
119 	    void (*)(void *, db_pgno_t, void *), void *));
120 void	*mpool_new __P((MPOOL *, db_pgno_t *, u_int));
121 void	*mpool_get __P((MPOOL *, db_pgno_t, u_int));
122 int	 mpool_delete __P((MPOOL *, void *));
123 int	 mpool_put __P((MPOOL *, void *, u_int));
124 int	 mpool_sync __P((MPOOL *));
125 int	 mpool_close __P((MPOOL *));
126 #ifdef STATISTICS
127 void	 mpool_stat __P((MPOOL *));
128 #endif
129 __END_DECLS
130 
131 #ifdef	__cplusplus
132 }
133 #endif
134 
135 #endif	/* !_KRB5_DB2_MPOOL_MPOOL_H */
136