1/*-
2 * Copyright (c) 2006 Ruslan Ermilov <ru@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, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef	_G_CACHE_H_
30#define	_G_CACHE_H_
31
32#include <sys/endian.h>
33
34#define	G_CACHE_CLASS_NAME	"CACHE"
35#define	G_CACHE_MAGIC		"GEOM::CACHE"
36#define	G_CACHE_VERSION		1
37
38#ifdef _KERNEL
39#define	G_CACHE_TYPE_MANUAL	0
40#define	G_CACHE_TYPE_AUTOMATIC	1
41
42#define	G_CACHE_DEBUG(lvl, ...)	do {					\
43	if (g_cache_debug >= (lvl)) {					\
44		printf("GEOM_CACHE");					\
45		if (g_cache_debug > 0)					\
46			printf("[%u]", lvl);				\
47		printf(": ");						\
48		printf(__VA_ARGS__);					\
49		printf("\n");						\
50	}								\
51} while (0)
52#define	G_CACHE_LOGREQ(bp, ...)	do {					\
53	if (g_cache_debug >= 2) {					\
54		printf("GEOM_CACHE[2]: ");				\
55		printf(__VA_ARGS__);					\
56		printf(" ");						\
57		g_print_bio(bp);					\
58		printf("\n");						\
59	}								\
60} while (0)
61
62#define	G_CACHE_BUCKETS		(1 << 3)
63#define	G_CACHE_BUCKET(bno)	((bno) & (G_CACHE_BUCKETS - 1))
64
65struct g_cache_softc {
66	struct g_geom	*sc_geom;
67	int		sc_type;
68	u_int		sc_bshift;
69	u_int		sc_bsize;
70	off_t		sc_tail;
71	struct mtx	sc_mtx;
72	struct callout	sc_callout;
73	LIST_HEAD(, g_cache_desc) sc_desclist[G_CACHE_BUCKETS];
74	TAILQ_HEAD(, g_cache_desc) sc_usedlist;
75	uma_zone_t	sc_zone;
76
77	u_int		sc_maxent;		/* max entries */
78	u_int		sc_nent;		/* allocated entries */
79	u_int		sc_nused;		/* re-useable entries */
80	u_int		sc_invalid;		/* invalid entries */
81
82	uintmax_t	sc_reads;		/* #reads */
83	uintmax_t	sc_readbytes;		/* bytes read */
84	uintmax_t	sc_cachereads;		/* #reads from cache */
85	uintmax_t	sc_cachereadbytes;	/* bytes read from cache */
86	uintmax_t	sc_cachehits;		/* cache hits */
87	uintmax_t	sc_cachemisses;		/* cache misses */
88	uintmax_t	sc_cachefull;		/* #times a cache was full */
89	uintmax_t	sc_writes;		/* #writes */
90	uintmax_t	sc_wrotebytes;		/* bytes written */
91};
92#define	sc_name	sc_geom->name
93
94struct g_cache_desc {
95	off_t		d_bno;			/* block number */
96	caddr_t		d_data;			/* data area */
97	struct bio	*d_biolist;		/* waiters */
98	time_t		d_atime;		/* access time */
99	int		d_flags;		/* flags */
100#define	D_FLAG_USED	(1 << 0)			/* can be reused */
101#define	D_FLAG_INVALID	(1 << 1)			/* invalid */
102	LIST_ENTRY(g_cache_desc) d_next;	/* list */
103	TAILQ_ENTRY(g_cache_desc) d_used;	/* used list */
104};
105
106#define	G_CACHE_NEXT_BIO1(bp)	(bp)->bio_driver1
107#define	G_CACHE_NEXT_BIO2(bp)	(bp)->bio_driver2
108#define	G_CACHE_DESC1(bp)	(bp)->bio_caller1
109#define	G_CACHE_DESC2(bp)	(bp)->bio_caller2
110
111#endif	/* _KERNEL */
112
113struct g_cache_metadata {
114	char		md_magic[16];		/* Magic value. */
115	uint32_t	md_version;		/* Version number. */
116	char		md_name[16];		/* Cache value. */
117	uint32_t	md_bsize;		/* Cache block size. */
118	uint32_t	md_size;		/* Cache size. */
119	uint64_t	md_provsize;		/* Provider's size. */
120};
121
122static __inline void
123cache_metadata_encode(const struct g_cache_metadata *md, u_char *data)
124{
125
126	bcopy(md->md_magic, data, sizeof(md->md_magic));
127	le32enc(data + 16, md->md_version);
128	bcopy(md->md_name, data + 20, sizeof(md->md_name));
129	le32enc(data + 36, md->md_bsize);
130	le32enc(data + 40, md->md_size);
131	le64enc(data + 44, md->md_provsize);
132}
133
134static __inline void
135cache_metadata_decode(const u_char *data, struct g_cache_metadata *md)
136{
137
138	bcopy(data, md->md_magic, sizeof(md->md_magic));
139	md->md_version = le32dec(data + 16);
140	bcopy(data + 20, md->md_name, sizeof(md->md_name));
141	md->md_bsize = le32dec(data + 36);
142	md->md_size = le32dec(data + 40);
143	md->md_provsize = le64dec(data + 44);
144}
145
146#endif	/* _G_CACHE_H_ */
147