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