git.sesse.net Git - bcachefs-tools-debian/blob - bcache.h

   1 #ifndef _BCACHE_H
   2 #define _BCACHE_H
   3
   4 static const char bcache_magic[] = {
   5         0xc6, 0x85, 0x73, 0xf6, 0x4e, 0x1a, 0x45, 0xca,
   6         0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81 };
   7
   8 #define SB_SECTOR               8
   9 #define SB_LABEL_SIZE           32
  10
  11 struct cache_sb {
  12         uint64_t                csum;
  13         uint64_t                offset; /* sector where this sb was written */
  14         uint64_t                version;
  15 #define CACHE_BACKING_DEV       1
  16
  17         uint8_t                 magic[16];
  18
  19         uint8_t                 uuid[16];
  20         union {
  21                 uint8_t         set_uuid[16];
  22                 uint64_t        set_magic;
  23         };
  24         uint8_t                 label[SB_LABEL_SIZE];
  25
  26         uint64_t                flags;
  27         uint64_t                seq;
  28         uint64_t                pad[8];
  29
  30         uint64_t                nbuckets;       /* device size */
  31         uint16_t                block_size;     /* sectors */
  32         uint16_t                bucket_size;    /* sectors */
  33
  34         uint16_t                nr_in_set;
  35         uint16_t                nr_this_dev;
  36
  37         uint32_t                last_mount;     /* time_t */
  38
  39         uint16_t                first_bucket;
  40         uint16_t                keys;           /* number of journal buckets */
  41         uint64_t                d[];            /* journal buckets */
  42 };
  43
  44 inline uint64_t crc64(const void *_data, size_t len);
  45
  46 #define node(i, j)              ((void *) ((i)->d + (j)))
  47 #define end(i)                  node(i, (i)->keys)
  48
  49 #define csum_set(i)                                                     \
  50         crc64(((void *) (i)) + 8, ((void *) end(i)) - (((void *) (i)) + 8))
  51
  52 #endif