fs/reiser4/dformat.h

   1 /* Copyright 2001, 2002, 2003 by Hans Reiser, licensing governed by
   2    reiser4/README */
   3
   4 /* Formats of on-disk data and conversion functions. */
   5
   6 /* put all item formats in the files describing the particular items,
   7    our model is, everything you need to do to add an item to reiser4,
   8    (excepting the changes to the plugin that uses the item which go
   9    into the file defining that plugin), you put into one file. */
  10 /* Data on disk are stored in little-endian format.
  11    To declare fields of on-disk structures, use d8, d16, d32 and d64.
  12    d??tocpu() and cputod??() to convert. */
  13
  14 #if !defined(__FS_REISER4_DFORMAT_H__)
  15 #define __FS_REISER4_DFORMAT_H__
  16
  17 #include <asm/byteorder.h>
  18 #include <asm/unaligned.h>
  19 #include <linux/types.h>
  20
  21 typedef __u8 d8;
  22 typedef __le16 d16;
  23 typedef __le32 d32;
  24 typedef __le64 d64;
  25
  26 #define PACKED __attribute__((packed))
  27
  28 /* data-type for block number */
  29 typedef __u64 reiser4_block_nr;
  30
  31 /* data-type for block number on disk, disk format */
  32 typedef __le64 reiser4_dblock_nr;
  33
  34 /**
  35  * disk_addr_eq - compare disk addresses
  36  * @b1: pointer to block number ot compare
  37  * @b2: pointer to block number ot compare
  38  *
  39  * Returns true if if disk addresses are the same
  40  */
  41 static inline int disk_addr_eq(const reiser4_block_nr * b1,
  42                                const reiser4_block_nr * b2)
  43 {
  44         assert("nikita-1033", b1 != NULL);
  45         assert("nikita-1266", b2 != NULL);
  46
  47         return !memcmp(b1, b2, sizeof *b1);
  48 }
  49
  50 /* structure of master reiser4 super block */
  51 typedef struct reiser4_master_sb {
  52         char magic[16];         /* "ReIsEr4" */
  53         __le16 disk_plugin_id;  /* id of disk layout plugin */
  54         __le16 blocksize;
  55         char uuid[16];          /* unique id */
  56         char label[16];         /* filesystem label */
  57         __le64 diskmap;         /* location of the diskmap. 0 if not present */
  58 } reiser4_master_sb;
  59
  60 /* __FS_REISER4_DFORMAT_H__ */
  61 #endif
  62
  63 /*
  64  * Local variables:
  65  * c-indentation-style: "K&R"
  66  * mode-name: "LC"
  67  * c-basic-offset: 8
  68  * tab-width: 8
  69  * fill-column: 79
  70  * End:
  71  */