sys/geom/cache/g_cache.h

   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
  65 struct 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
  94 struct 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
 113 struct 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
 122 static __inline void
 123 cache_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
 134 static __inline void
 135 cache_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_ */