tfs.h

   1 #ifndef TFS_H
   2 #define TFS_H
   3
   4 #include <stdint.h>
   5
   6 #define TFS_ROOT_INODE  1
   7 #define TFS_FILE        0x1
   8 #define TFS_DIR         0x2
   9
  10 /* namei: path lookup flags */
  11 #define LOOKUP_PARENT  0x1
  12
  13 /* just support I_FILE and I_DIR only currently */
  14 enum tfs_inode_mode { I_FILE, I_DIR, I_UNKNOWN };
  15
  16 static inline int get_mode(int mode)
  17 {
  18         if (mode & TFS_FILE)
  19                 return I_FILE;
  20         else if (mode & TFS_DIR)
  21                 return I_DIR;
  22         else
  23                 return I_UNKNOWN;
  24 }
  25
  26 /* It's really enought for a test file system */
  27 #define TFS_N_BLOCKS 8
  28
  29 struct tfs_inode {
  30         uint16_t i_mode;                /* File mode */
  31         uint16_t i_uid;                 /* Owner UID */
  32         uint32_t i_size;                /* File size */
  33         uint32_t i_atime;               /* Access time */
  34         uint32_t i_ctime;               /* Create time */
  35         uint32_t i_mtime;               /* modify time */
  36         uint32_t i_dtime;               /* delete time */
  37         uint32_t i_block[TFS_N_BLOCKS]; /* block address of file's count */
  38         uint32_t i_flags;               /* flags */
  39         uint32_t i_reserved[1];
  40 };
  41
  42 /*
  43  * The inode structure in memory, including the detail file information
  44  */
  45 struct inode {
  46         int          i_mode;   /* FILE or DIR */
  47         uint32_t     i_size;
  48         uint32_t     i_ino;    /* Inode number */
  49         uint32_t     i_atime;  /* Access time */
  50         uint32_t     i_mtime;  /* Modify time */
  51         uint32_t     i_ctime;  /* Create time */
  52         uint32_t     i_dtime;  /* Delete time */
  53         uint32_t *   i_data;   /* The block address array where the file stores */
  54         uint32_t     i_flags;
  55 };
  56
  57 /* The max lenght of each file name */
  58 #define TFS_NAME_LEN 28
  59 struct tfs_dir_entry {
  60         uint32_t d_inode;               /* inode number */
  61         char     d_name[TFS_NAME_LEN];  /* entry name */
  62 };
  63
  64 #define TFS_MAGIC  0x4c534654           /* TFSL */
  65
  66 /* TFS super block */
  67 struct tfs_super_block {
  68         uint32_t s_inodes_count;        /* Max file count */
  69         uint32_t s_blocks_count;
  70         uint32_t s_free_blocks_count;
  71         uint32_t s_free_inodes_count;
  72         uint32_t s_magic;               /* TFS's magic signature */
  73         uint32_t s_block_shift;         /* Block size */
  74
  75         uint32_t s_inode_bitmap;
  76         uint32_t s_block_bitmap;
  77         uint32_t s_inode_table;
  78         uint32_t s_data_area;           /* where the data starts */
  79
  80
  81         uint32_t s_offset;              /* In which sector the fs stored */
  82         uint32_t s_reserved[117];
  83 };
  84
  85 /* TFS super block  info */
  86 struct tfs_sb_info {
  87         uint32_t s_inodes_count;        /* Max file count */
  88         uint32_t s_blocks_count;
  89         uint32_t s_free_blocks_count;
  90         uint32_t s_free_inodes_count;
  91         uint32_t s_block_shift;         /* Block size in bits */
  92         uint32_t s_block_size;          /* Block size in bytes */
  93
  94         uint32_t s_inode_bitmap;
  95         uint32_t s_inode_bitmap_count;
  96         uint32_t s_block_bitmap;
  97         uint32_t s_block_bitmap_count;
  98         uint32_t s_inode_table;
  99         uint32_t s_inode_table_count;
 100         uint32_t s_data_area;           /* where the data starts */
 101
 102
 103         uint32_t s_offset;              /* In which sector the fs stored */
 104
 105         int      s_inodes_per_block;
 106 };
 107
 108
 109 #define TFS_INODES_PER_BLOCK(sbi) (sbi->s_inodes_per_block)
 110
 111 #define TFS_DEBUG printf
 112
 113 #define roundup(x, y) ((x) / (y) + (((x) % (y)) ? 1 : 0))
 114
 115 /* utils.c */
 116 extern int set_bit(void *, unsigned int);
 117 extern int clear_bit(void *, unsigned int);
 118 extern int test_bit(const void *, unsigned int);
 119 extern uint32_t find_first_zero(void *, void *);
 120
 121 extern int write_sector(uint32_t, void *, int);
 122 extern int read_sector(uint32_t, void *, int);
 123 extern int tfs_bread(struct tfs_sb_info *, uint32_t , void *);
 124 extern int tfs_bwrite(struct tfs_sb_info *, uint32_t, void *);
 125
 126 /* super.c */
 127 struct tfs_sb_info * tfs_mount(void);
 128 struct tfs_sb_info * tfs_mount_by_fsname(const char *);
 129
 130 /* ialloc.c */
 131 int tfs_free_inode(struct tfs_sb_info *, int);
 132 int tfs_alloc_inode(struct tfs_sb_info *, int);
 133
 134 /* balloc.c */
 135 int tfs_alloc_block(struct tfs_sb_info *, uint32_t);
 136 int tfs_free_block(struct tfs_sb_info *, uint32_t);
 137
 138
 139 /* dir.c */
 140 struct tfs_dir_entry *tfs_find_entry(struct tfs_sb_info *, const char *, struct inode *);
 141 int tfs_add_entry(struct tfs_sb_info *, struct inode *, const char *, int , int *);
 142 int tfs_mkdir(struct tfs_sb_info *, const char *);
 143
 144 /* inode.c */
 145 struct inode *new_inode(int);
 146 void free_inode(struct inode *);
 147 struct inode *tfs_root_init(struct tfs_sb_info *);
 148 struct inode *tfs_iget_root(struct tfs_sb_info *);
 149 struct inode *tfs_iget(struct tfs_sb_info *, char *, struct inode *);
 150 struct inode *tfs_namei(struct tfs_sb_info *, const char *, uint32_t);
 151 int tfs_iwrite(struct tfs_sb_info *, struct inode *);
 152 struct inode *tfs_mknod(struct tfs_sb_info *, const char *, int, struct inode **);
 153
 154 #endif /* tfs.h */