minix/fs/ext2/inode.h

   1 /* Inode table.  This table holds inodes that are currently in use.  In some
   2  * cases they have been opened by an open() or creat() system call, in other
   3  * cases the file system itself needs the inode for one reason or another,
   4  * such as to search a directory for a path name.
   5  * The first part of the struct holds fields that are present on the
   6  * disk; the second part holds fields not present on the disk.
   7  * The disk inode part is also declared in "type.h" as 'd_inode'
   8  *
   9  */
  10
  11 #ifndef EXT2_INODE_H
  12 #define EXT2_INODE_H
  13
  14 #include <sys/queue.h>
  15
  16 /* Disk part of inode structure was taken from
  17  * linux/include/linux/ext2_fs.h.
  18  */
  19 EXTERN struct inode {
  20     u16_t  i_mode;         /* File mode */
  21     u16_t  i_uid;          /* Low 16 bits of Owner Uid */
  22     u32_t  i_size;         /* Size in bytes */
  23     u32_t  i_atime;        /* Access time */
  24     u32_t  i_ctime;        /* Creation time */
  25     u32_t  i_mtime;        /* Modification time */
  26     u32_t  i_dtime;        /* Deletion Time */
  27     u16_t  i_gid;          /* Low 16 bits of Group Id */
  28     u16_t  i_links_count;  /* Links count */
  29     u32_t  i_blocks;       /* 512-byte blocks count */
  30     u32_t  i_flags;        /* File flags */
  31     union {
  32         struct {
  33                 u32_t  l_i_reserved1;
  34         } linux1;
  35         struct {
  36                 u32_t  h_i_translator;
  37         } hurd1;
  38         struct {
  39                 u32_t  m_i_reserved1;
  40         } masix1;
  41     } osd1;                         /* OS dependent 1 */
  42     u32_t  i_block[EXT2_N_BLOCKS];  /* Pointers to blocks */
  43     u32_t  i_generation;            /* File version (for NFS) */
  44     u32_t  i_file_acl;              /* File ACL */
  45     u32_t  i_dir_acl;               /* Directory ACL */
  46     u32_t  i_faddr;                 /* Fragment address */
  47     union {
  48         struct {
  49             u8_t    l_i_frag;       /* Fragment number */
  50             u8_t    l_i_fsize;      /* Fragment size */
  51             u16_t   i_pad1;
  52             u16_t  l_i_uid_high;   /* these 2 fields    */
  53             u16_t  l_i_gid_high;   /* were reserved2[0] */
  54             u32_t   l_i_reserved2;
  55         } linux2;
  56         struct {
  57             u8_t    h_i_frag;       /* Fragment number */
  58             u8_t    h_i_fsize;      /* Fragment size */
  59             u16_t  h_i_mode_high;
  60             u16_t  h_i_uid_high;
  61             u16_t  h_i_gid_high;
  62             u32_t  h_i_author;
  63         } hurd2;
  64         struct {
  65             u8_t    m_i_frag;       /* Fragment number */
  66             u8_t    m_i_fsize;      /* Fragment size */
  67             u16_t   m_pad1;
  68             u32_t   m_i_reserved2[2];
  69         } masix2;
  70     } osd2;                         /* OS dependent 2 */
  71
  72     /* The following items are not present on the disk. */
  73     dev_t i_dev;                /* which device is the inode on */
  74     ino_t i_num;               /* inode number on its (minor) device */
  75     int i_count;                /* # times inode used; 0 means slot is free */
  76     struct super_block *i_sp;   /* pointer to super block for inode's device */
  77     char i_dirt;                /* CLEAN or DIRTY */
  78     block_t i_bsearch;          /* where to start search for new blocks,
  79                                  * also this is last allocated block.
  80                                  */
  81     off_t i_last_pos_bl_alloc;  /* last write position for which we allocated
  82                                  * a new block (should be block i_bsearch).
  83                                  * used to check for sequential operation.
  84                                  */
  85     off_t i_last_dpos;          /* where to start dentry search */
  86     int i_last_dentry_size;     /* size of last found dentry */
  87
  88     char i_mountpoint;          /* true if mounted on */
  89
  90     char i_seek;                /* set on LSEEK, cleared on READ/WRITE */
  91     char i_update;              /* the ATIME, CTIME, and MTIME bits are here */
  92
  93     block_t i_prealloc_blocks[EXT2_PREALLOC_BLOCKS];    /* preallocated blocks */
  94     int i_prealloc_count;       /* number of preallocated blocks */
  95     int i_prealloc_index;       /* index into i_prealloc_blocks */
  96     int i_preallocation;        /* use preallocation for this inode, normally
  97                                  * it's reset only when non-sequential write
  98                                  * happens.
  99                                  */
 100
 101     LIST_ENTRY(inode) i_hash;     /* hash list */
 102     TAILQ_ENTRY(inode) i_unused;  /* free and unused list */
 103
 104 } inode[NR_INODES];
 105
 106
 107 /* list of unused/free inodes */
 108 EXTERN TAILQ_HEAD(unused_inodes_t, inode)  unused_inodes;
 109
 110 /* inode hashtable */
 111 EXTERN LIST_HEAD(inodelist, inode)         hash_inodes[INODE_HASH_SIZE];
 112
 113 EXTERN unsigned int inode_cache_hit;
 114 EXTERN unsigned int inode_cache_miss;
 115
 116 /* Field values.  Note that CLEAN and DIRTY are defined in "const.h" */
 117 #define NO_SEEK            0    /* i_seek = NO_SEEK if last op was not SEEK */
 118 #define ISEEK              1    /* i_seek = ISEEK if last op was SEEK */
 119
 120 #endif /* EXT2_INODE_H */