{"id":1627,"date":"2012-04-04T06:34:46","date_gmt":"2012-04-03T21:34:46","guid":{"rendered":"http:\/\/peta.okechan.net\/blog\/?p=1627"},"modified":"2012-04-04T06:35:29","modified_gmt":"2012-04-03T21:35:29","slug":"xv6-60-chapter-5-file-system-inodes","status":"publish","type":"post","link":"https:\/\/peta.okechan.net\/blog\/archives\/1627","title":{"rendered":"[xv6 #60] Chapter 5 – File system – Inodes"},"content":{"rendered":"

\u30c6\u30ad\u30b9\u30c8\u306e69\u301c70\u30da\u30fc\u30b8<\/p>\n

\u672c\u6587<\/h3>\n

inode\u3068\u3044\u3046\u7528\u8a9e\u306f\u95a2\u9023\u3059\u308b2\u3064\u306e\u610f\u5473\u3092\u6301\u3064\u3002
\n\u3072\u3068\u3064\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u306e\u30b5\u30a4\u30ba\u3068\u30c7\u30fc\u30bf\u30d6\u30ed\u30c3\u30af\u306e\u30bb\u30af\u30bf\u756a\u53f7\u306e\u30ea\u30b9\u30c8\u3092\u542b\u3080\u30c7\u30a3\u30b9\u30af\u4e0a\u306e\u30c7\u30fc\u30bf\u69cb\u9020\u3092\u6307\u3059\u3002
\n\u3082\u3046\u3072\u3068\u3064\u306f\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306e\u30b3\u30d4\u30fc\u306f\u3082\u3061\u308d\u3093\u3001\u30ab\u30fc\u30cd\u30eb\u3067\u5fc5\u8981\u3068\u306a\u308b\u8ffd\u52a0\u306e\u60c5\u5831\u3092\u542b\u3080\u3001\u30e1\u30e2\u30ea\u4e0a\u306e\u30c7\u30fc\u30bf\u69cb\u9020\u3092\u6307\u3059\u3002<\/p>\n

\u3059\u3079\u3066\u306e\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u3001inode\u30d6\u30ed\u30c3\u30af\u3068\u547c\u3070\u308c\u308b\u30c7\u30a3\u30b9\u30af\u306e\u9023\u7d9a\u3057\u305f\u30a8\u30ea\u30a2\u306e\u4e2d\u306b\u307e\u3068\u3081\u3089\u308c\u308b\u3002
\n\u305d\u308c\u305e\u308c\u306einode\u306f\u540c\u3058\u30b5\u30a4\u30ba\u306a\u306e\u3067\u3001n\u3068\u3044\u3046\u756a\u53f7\u3092\u4e0e\u3048\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306en\u756a\u76ee\u306einode\u3092\u635c\u3059\u306e\u306f\u7c21\u5358\u3067\u3042\u308b\u3002
\n\u5b9f\u969b\u3001\u3053\u306e\u756a\u53f7n\u306f\u3001inode\u756a\u53f7\u3082\u3057\u304f\u306fi-number\u3068\u547c\u3070\u308c\u3001\u5b9f\u88c5\u4e2d\u3067inode\u3092\u7279\u5b9a\u3059\u308b\u65b9\u6cd5\u3068\u306a\u308b\u3002<\/p>\n

\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u3001dinode\u69cb\u9020\u4f53\u3068\u3057\u3066\u5b9a\u7fa9\u3055\u308c\u308b\u3002
\ntype\u3068\u3044\u3046\u30d5\u30a3\u30fc\u30eb\u30c9\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u304b\u3001\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u304b\u3001\u7279\u6b8a\u306a\u30d5\u30a1\u30a4\u30eb\uff08\u30c7\u30d0\u30a4\u30b9\uff09\u304b\u3092\u533a\u5225\u3059\u308b\u305f\u3081\u306b\u3042\u308b\u3002
\ntype\u304c\u30bc\u30ed\u3060\u3063\u305f\u3089\u3001\u305d\u306e\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u7a7a\u304d\u3067\u3042\u308b\u3068\u3044\u3046\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u3002<\/p>\n

fs.h<\/p>\n

\/\/ On-disk file system format. \r\n\/\/ Both the kernel and user programs use this header file.\r\n\r\n\/\/ Block 0 is unused.  Block 1 is super block.\r\n\/\/ Inodes start at block 2.\r\n\r\n#define ROOTINO 1  \/\/ root i-number\r\n#define BSIZE 512  \/\/ block size\r\n\r\n\/\/ File system super block\r\nstruct superblock {\r\n  uint size;         \/\/ Size of file system image (blocks)\r\n  uint nblocks;      \/\/ Number of data blocks\r\n  uint ninodes;      \/\/ Number of inodes.\r\n  uint nlog;         \/\/ Number of log blocks\r\n};\r\n\r\n#define NDIRECT 12\r\n#define NINDIRECT (BSIZE \/ sizeof(uint))\r\n#define MAXFILE (NDIRECT + NINDIRECT)\r\n\r\n\/\/ On-disk inode structure\r\nstruct dinode {\r\n  short type;           \/\/ File type\r\n  short major;          \/\/ Major device number (T_DEV only)\r\n  short minor;          \/\/ Minor device number (T_DEV only)\r\n  short nlink;          \/\/ Number of links to inode in file system\r\n  uint size;            \/\/ Size of file (bytes)\r\n  uint addrs[NDIRECT+1];   \/\/ Data block addresses\r\n};\r\n\r\n\/\/ Inodes per block.\r\n#define IPB           (BSIZE \/ sizeof(struct dinode))\r\n\r\n\/\/ Block containing inode i\r\n#define IBLOCK(i)     ((i) \/ IPB + 2)\r\n\r\n\/\/ Bitmap bits per block\r\n#define BPB           (BSIZE*8)\r\n\r\n\/\/ Block containing bit for block b\r\n#define BBLOCK(b, ninodes) (b\/BPB + (ninodes)\/IPB + 3)\r\n\r\n\/\/ Directory is a file containing a sequence of dirent structures.\r\n#define DIRSIZ 14\r\n\r\nstruct dirent {\r\n  ushort inum;\r\n  char name[DIRSIZ];\r\n};<\/pre>\n
\u30ab\u30fc\u30cd\u30eb\u306f\u3001\u3088\u304f\u4f7f\u308f\u308c\u308binode\u306e\u307e\u3068\u307e\u308a\u3092\u30e1\u30e2\u30ea\u4e0a\u306b\u4fdd\u6301\u3059\u308b\u3002
\ninode\u69cb\u9020\u4f53\u306f\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306edinode\u69cb\u9020\u4f53\u306e\u30e1\u30e2\u30ea\u4e0a\u306e\u30b3\u30d4\u30fc\u3068\u3057\u3066\u4f7f\u308f\u308c\u308b\u3002
\n\u30ab\u30fc\u30cd\u30eb\u306f\u3001C\u30dd\u30a4\u30f3\u30bf\u304c\u3042\u308binode\u3092\u53c2\u7167\u3057\u3066\u308b\u3068\u304d\u3060\u3051\u3001\u305d\u306einode\u3092\u30e1\u30e2\u30ea\u306b\u683c\u7d0d\u3059\u308b\u3002
\n\u305d\u3057\u3066\u3001\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u304c\u30bc\u30ed\u306b\u306a\u3063\u305f\u3089\u3001\u30e1\u30e2\u30ea\u304b\u3089\u305d\u306einode\u3092\u7834\u68c4\u3059\u308b\u3002
\niget\u95a2\u6570\u3001iput\u95a2\u6570\u306f\u3001\u3072\u3068\u3064\u306einode\u3078\u306e\u30dd\u30a4\u30f3\u30bf\u3092\u7372\u5f97\u3057\u305f\u308a\u89e3\u653e\u3057\u305f\u308a\u3057\u3064\u3064\u305d\u306e\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u3092\u5909\u66f4\u3059\u308b\u3002
\n\u3042\u308binode\u306b\u5bfe\u3059\u308b\u30dd\u30a4\u30f3\u30bf\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u30c7\u30a3\u30b9\u30af\u30ea\u30d7\u30bf\u3084\u3001\u73fe\u5728\u306e\u4f5c\u696d\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u3084\u3001exec\u306e\u3088\u3046\u306a\u4e00\u6642\u7684\u306a\u30ab\u30fc\u30cd\u30eb\u306e\u30b3\u30fc\u30c9\u306b\u3088\u3063\u3066\u751f\u6210\u3055\u308c\u308b\u3002<\/p>\n
file.h<\/p>\n
struct file {\r\n  enum { FD_NONE, FD_PIPE, FD_INODE } type;\r\n  int ref; \/\/ reference count\r\n  char readable;\r\n  char writable;\r\n  struct pipe *pipe;\r\n  struct inode *ip;\r\n  uint off;\r\n};\r\n\r\n\r\n\/\/ in-core file system types\r\n\r\nstruct inode {\r\n  uint dev;           \/\/ Device number\r\n  uint inum;          \/\/ Inode number\r\n  int ref;            \/\/ Reference count\r\n  int flags;          \/\/ I_BUSY, I_VALID\r\n\r\n  short type;         \/\/ copy of disk inode\r\n  short major;\r\n  short minor;\r\n  short nlink;\r\n  uint size;\r\n  uint addrs[NDIRECT+1];\r\n};\r\n\r\n#define I_BUSY 0x1\r\n#define I_VALID 0x2\r\n\r\n\/\/ device implementations\r\n\r\nstruct devsw {\r\n  int (*read)(struct inode*, char*, int);\r\n  int (*write)(struct inode*, char*, int);\r\n};\r\n\r\nextern struct devsw devsw[];\r\n\r\n#define CONSOLE 1<\/pre>\n
iget\u95a2\u6570\u304c\u8fd4\u3059inode\u69cb\u9020\u4f53\u306f\u3001\u6709\u7528\u306a\u5185\u5bb9\u3092\u4f55\u3082\u542b\u3093\u3067\u3044\u306a\u3044\u3060\u308d\u3046\u3002
\n\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306e\u30b3\u30d4\u30fc\u3092\u4fdd\u6301\u3059\u308b\u3053\u3068\u3092\u4fdd\u8a3c\u3059\u308b\u305f\u3081\u3001ilock\u95a2\u6570\u3092\u547c\u3070\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002
\n\u3053\u306e\u95a2\u6570\u306f\u3001inode\u3092\u30ed\u30c3\u30af\u3057\uff08\u4ed6\u306e\u30d7\u30ed\u30bb\u30b9\u304c\u540c\u3058inode\u306b\u5bfe\u3057\u3066ilock\u51fa\u6765\u306a\u3044\u3088\u3046\u306b\u3059\u308b\u305f\u3081\u306b\uff09\u3001\u305d\u3057\u3066\u8aad\u307f\u53d6\u308a\u6e08\u307f\u3067\u306a\u3051\u308c\u3070\u3001\u30c7\u30a3\u30b9\u30af\u304b\u3089inode\u3092\u8aad\u307f\u53d6\u308b\u3002
\niunlock\u95a2\u6570\u306f\u3001inode\u306b\u5bfe\u3059\u308b\u30ed\u30c3\u30af\u3092\u89e3\u653e\u3059\u308b\u3002
\ninode\u30dd\u30a4\u30f3\u30bf\u306e\u7372\u5f97\u3092\u3001\u30ed\u30c3\u30af\u304b\u3089\u5206\u96e2\u3059\u308b\u3053\u3068\u306f\u3001\u3044\u304f\u3064\u304b\u306e\u5834\u5408\u306b\u30c7\u30c3\u30c9\u30ed\u30c3\u30af\u3092\u907f\u3051\u308b\u52a9\u3051\u306b\u306a\u308b\u3002
\n\u4f8b\u3048\u3070\u3001\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u3092\u63a2\u7d22\u3059\u308b\u5834\u5408\u3067\u3042\u308b\u3002
\n\u8907\u6570\u306e\u30d7\u30ed\u30bb\u30b9\u306f\u3001iget\u95a2\u6570\u306b\u3088\u3063\u3066\u8fd4\u3055\u308c\u305f\u3042\u308binode\u3078\u306eC\u30dd\u30a4\u30f3\u30bf\u3092\u4fdd\u6301\u3059\u308b\u3053\u3068\u304c\u51fa\u6765\u308b\u304c\u3001\u4e00\u5ea6\u306b\u4e00\u3064\u306e\u30d7\u30ed\u30bb\u30b9\u3060\u3051\u304c\u305d\u306einode\u3092\u30ed\u30c3\u30af\u51fa\u6765\u308b\u3002<\/p>\n
inode\u30ad\u30e3\u30c3\u30b7\u30e5\u306f\u3001\u30ab\u30fc\u30cd\u30eb\u306e\u30b3\u30fc\u30c9\u3084C\u30dd\u30a4\u30f3\u30bf\u3092\u4fdd\u6301\u3059\u308b\u30c7\u30fc\u30bf\u69cb\u9020\u306e\u305f\u3081\u306b\u3001inode\u3092\u30ad\u30e3\u30c3\u30b7\u30e5\u3059\u308b\u306e\u307f\u3067\u3042\u308b\u3002
\ninode\u30ad\u30e3\u30c3\u30b7\u30e5\u306e\u4e3b\u306a\u5f79\u5272\u306f\u3001\u8907\u6570\u306e\u30d7\u30ed\u30bb\u30b9\u306b\u3088\u308b\u30a2\u30af\u30bb\u30b9\u3092\u78ba\u5b9f\u306b\u540c\u671f\u5316\u3059\u308b\u3053\u3068\u3067\u3042\u308a\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u3059\u308b\u3053\u3068\u3067\u306f\u306a\u3044\u3002
\n\u3042\u308binode\u304c\u983b\u7e41\u306b\u5229\u7528\u3055\u308c\u308b\u5834\u5408\u3001inode\u30ad\u30e3\u30c3\u30b7\u30e5\u306b\u3088\u3063\u3066\u30ad\u30e3\u30c3\u30b7\u30e5\u3055\u308c\u306a\u304f\u3066\u3082\u3001\u30d0\u30c3\u30d5\u30a1\u30ad\u30e3\u30c3\u30b7\u30e5\u306b\u3088\u3063\u3066\u3001\u30e1\u30e2\u30ea\u4e0a\u306b\u9069\u5207\u306b\u4fdd\u6301\u3055\u308c\u308b\u3002<\/p>\n
\u611f\u60f3<\/h3>\n
inode\u306e\u6982\u8981\u3067\u3059\u3002
\n\u30d8\u30c3\u30c0\u306e\u30bd\u30fc\u30b9\u306f\u8f09\u305b\u3066\u307e\u3059\u304c\u3001\u5404\u95a2\u6570\u306e\u30bd\u30fc\u30b9\u306f\u5f8c\u306e\u7bc0\u3067\u8aac\u660e\u304c\u3042\u308b\u306f\u305a\u306a\u306e\u3067\u3001\u4eca\u56de\u306f\u8f09\u305b\u3066\u307e\u305b\u3093\u3002<\/p>\n
\u30e1\u30e2\u30ea\u4e0a\u306binode\u306e\u8907\u88fd\u3092\u6301\u3064\u306e\u306f\u3001\u4e3b\u306b\u30ad\u30e3\u30c3\u30b7\u30e5\u306e\u70ba\u3067\u306f\u306a\u304f\u3001\u540c\u3058inode\u306b\u5bfe\u3059\u308b\u30a2\u30af\u30bb\u30b9\u3092\u540c\u671f\u5316\u3059\u308b\u76ee\u7684\u306e\u70ba\u306e\u3088\u3046\u3067\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u30c6\u30ad\u30b9\u30c8\u306e69\u301c70\u30da\u30fc\u30b8<\/p>\n
\u672c\u6587<\/h3>\n
inode\u3068\u3044\u3046\u7528\u8a9e\u306f\u95a2\u9023\u3059\u308b2\u3064\u306e\u610f\u5473\u3092\u6301\u3064\u3002
\n\u3072\u3068\u3064\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u306e\u30b5\u30a4\u30ba\u3068\u30c7\u30fc\u30bf\u30d6\u30ed\u30c3\u30af\u306e\u30bb\u30af\u30bf\u756a\u53f7\u306e\u30ea\u30b9\u30c8\u3092\u542b\u3080\u30c7\u30a3\u30b9\u30af\u4e0a\u306e\u30c7\u30fc\u30bf\u69cb\u9020\u3092\u6307\u3059\u3002
\n\u3082\u3046\u3072\u3068\u3064\u306f\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306e\u30b3\u30d4\u30fc\u306f\u3082\u3061\u308d\u3093\u3001\u30ab\u30fc\u30cd\u30eb\u3067\u5fc5\u8981\u3068\u306a\u308b\u8ffd\u52a0\u306e\u60c5\u5831\u3092\u542b\u3080\u3001\u30e1\u30e2\u30ea\u4e0a\u306e\u30c7\u30fc\u30bf\u69cb\u9020\u3092\u6307\u3059\u3002<\/p>\n
\u3059\u3079\u3066\u306e\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u3001inode\u30d6\u30ed\u30c3\u30af\u3068\u547c\u3070\u308c\u308b\u30c7\u30a3\u30b9\u30af\u306e\u9023\u7d9a\u3057\u305f\u30a8\u30ea\u30a2\u306e\u4e2d\u306b\u307e\u3068\u3081\u3089\u308c\u308b\u3002
\n\u305d\u308c\u305e\u308c\u306einode\u306f\u540c\u3058\u30b5\u30a4\u30ba\u306a\u306e\u3067\u3001n\u3068\u3044\u3046\u756a\u53f7\u3092\u4e0e\u3048\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306en\u756a\u76ee\u306einode\u3092\u635c\u3059\u306e\u306f\u7c21\u5358\u3067\u3042\u308b\u3002
\n\u5b9f\u969b\u3001\u3053\u306e\u756a\u53f7n\u306f\u3001inode\u756a\u53f7\u3082\u3057\u304f\u306fi-number\u3068\u547c\u3070\u308c\u3001\u5b9f\u88c5\u4e2d\u3067inode\u3092\u7279\u5b9a\u3059\u308b\u65b9\u6cd5\u3068\u306a\u308b\u3002<\/p>\n
\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u3001dinode\u69cb\u9020\u4f53\u3068\u3057\u3066\u5b9a\u7fa9\u3055\u308c\u308b\u3002
\ntype\u3068\u3044\u3046\u30d5\u30a3\u30fc\u30eb\u30c9\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u304b\u3001\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u304b\u3001\u7279\u6b8a\u306a\u30d5\u30a1\u30a4\u30eb\uff08\u30c7\u30d0\u30a4\u30b9\uff09\u304b\u3092\u533a\u5225\u3059\u308b\u305f\u3081\u306b\u3042\u308b\u3002
\ntype\u304c\u30bc\u30ed\u3060\u3063\u305f\u3089\u3001\u305d\u306e\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306f\u7a7a\u304d\u3067\u3042\u308b\u3068\u3044\u3046\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u3002<\/p>\n
fs.h<\/p>\n
\/\/ On-disk file system format. \r\n\/\/ Both the kernel and user programs use this header file.\r\n\r\n\/\/ Block 0 is unused.  Block 1 is super block.\r\n\/\/ Inodes start at block 2.\r\n\r\n#define ROOTINO 1  \/\/ root i-number\r\n#define BSIZE 512  \/\/ block size\r\n\r\n\/\/ File system super block\r\nstruct superblock {\r\n  uint size;         \/\/ Size of file system image (blocks)\r\n  uint nblocks;      \/\/ Number of data blocks\r\n  uint ninodes;      \/\/ Number of inodes.\r\n  uint nlog;         \/\/ Number of log blocks\r\n};\r\n\r\n#define NDIRECT 12\r\n#define NINDIRECT (BSIZE \/ sizeof(uint))\r\n#define MAXFILE (NDIRECT + NINDIRECT)\r\n\r\n\/\/ On-disk inode structure\r\nstruct dinode {\r\n  short type;           \/\/ File type\r\n  short major;          \/\/ Major device number (T_DEV only)\r\n  short minor;          \/\/ Minor device number (T_DEV only)\r\n  short nlink;          \/\/ Number of links to inode in file system\r\n  uint size;            \/\/ Size of file (bytes)\r\n  uint addrs[NDIRECT+1];   \/\/ Data block addresses\r\n};\r\n\r\n\/\/ Inodes per block.\r\n#define IPB           (BSIZE \/ sizeof(struct dinode))\r\n\r\n\/\/ Block containing inode i\r\n#define IBLOCK(i)     ((i) \/ IPB + 2)\r\n\r\n\/\/ Bitmap bits per block\r\n#define BPB           (BSIZE*8)\r\n\r\n\/\/ Block containing bit for block b\r\n#define BBLOCK(b, ninodes) (b\/BPB + (ninodes)\/IPB + 3)\r\n\r\n\/\/ Directory is a file containing a sequence of dirent structures.\r\n#define DIRSIZ 14\r\n\r\nstruct dirent {\r\n  ushort inum;\r\n  char name[DIRSIZ];\r\n};<\/pre>\n
\u30ab\u30fc\u30cd\u30eb\u306f\u3001\u3088\u304f\u4f7f\u308f\u308c\u308binode\u306e\u307e\u3068\u307e\u308a\u3092\u30e1\u30e2\u30ea\u4e0a\u306b\u4fdd\u6301\u3059\u308b\u3002
\ninode\u69cb\u9020\u4f53\u306f\u3001\u30c7\u30a3\u30b9\u30af\u4e0a\u306edinode\u69cb\u9020\u4f53\u306e\u30e1\u30e2\u30ea\u4e0a\u306e\u30b3\u30d4\u30fc\u3068\u3057\u3066\u4f7f\u308f\u308c\u308b\u3002
\n\u30ab\u30fc\u30cd\u30eb\u306f\u3001C\u30dd\u30a4\u30f3\u30bf\u304c\u3042\u308binode\u3092\u53c2\u7167\u3057\u3066\u308b\u3068\u304d\u3060\u3051\u3001\u305d\u306einode\u3092\u30e1\u30e2\u30ea\u306b\u683c\u7d0d\u3059\u308b\u3002
\n\u305d\u3057\u3066\u3001\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u304c\u30bc\u30ed\u306b\u306a\u3063\u305f\u3089\u3001\u30e1\u30e2\u30ea\u304b\u3089\u305d\u306einode\u3092\u7834\u68c4\u3059\u308b\u3002
\niget\u95a2\u6570\u3001iput\u95a2\u6570\u306f\u3001\u3072\u3068\u3064\u306einode\u3078\u306e\u30dd\u30a4\u30f3\u30bf\u3092\u7372\u5f97\u3057\u305f\u308a\u89e3\u653e\u3057\u305f\u308a\u3057\u3064\u3064\u305d\u306e\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u3092\u5909\u66f4\u3059\u308b\u3002
\n\u3042\u308binode\u306b\u5bfe\u3059\u308b\u30dd\u30a4\u30f3\u30bf\u306f\u3001\u30d5\u30a1\u30a4\u30eb\u30c7\u30a3\u30b9\u30af\u30ea\u30d7\u30bf\u3084\u3001\u73fe\u5728\u306e\u4f5c\u696d\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u3084\u3001exec\u306e\u3088\u3046\u306a\u4e00\u6642\u7684\u306a\u30ab\u30fc\u30cd\u30eb\u306e\u30b3\u30fc\u30c9\u306b\u3088\u3063\u3066\u751f\u6210\u3055\u308c\u308b\u3002<\/p>\n
file.h<\/p>\n
struct file {\r\n  enum { FD_NONE, FD_PIPE, FD_INODE } type;\r\n  int ref; \/\/ reference count\r\n  char readable;\r\n  char writable;\r\n  struct pipe *pipe;\r\n  struct inode *ip;\r\n  uint off;\r\n};\r\n\r\n\r\n\/\/ in-core file system types\r\n\r\nstruct inode {\r\n  uint dev;           \/\/ Device number\r\n  uint inum;          \/\/ Inode number\r\n  int ref;            \/\/ Reference count\r\n  int flags;          \/\/ I_BUSY, I_VALID\r\n\r\n  short type;         \/\/ copy of disk inode\r\n  short major;\r\n  short minor;\r\n  short nlink;\r\n  uint size;\r\n  uint addrs[NDIRECT+1];\r\n};\r\n\r\n#define I_BUSY 0x1\r\n#define I_VALID 0x2\r\n\r\n\/\/ device implementations\r\n\r\nstruct devsw {\r\n  int (*read)(struct inode*, char*, int);\r\n  int (*write)(struct inode*, char*, int);\r\n};\r\n\r\nextern struct devsw devsw[];\r\n\r\n#define CONSOLE 1<\/pre>\n
iget\u95a2\u6570\u304c\u8fd4\u3059inode\u69cb\u9020\u4f53\u306f\u3001\u6709\u7528\u306a\u5185\u5bb9\u3092\u4f55\u3082\u542b\u3093\u3067\u3044\u306a\u3044\u3060\u308d\u3046\u3002
\n\u30c7\u30a3\u30b9\u30af\u4e0a\u306einode\u306e\u30b3\u30d4\u30fc\u3092\u4fdd\u6301\u3059\u308b\u3053\u3068\u3092\u4fdd\u8a3c\u3059\u308b\u305f\u3081\u3001ilock\u95a2\u6570\u3092\u547c\u3070\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002
\n\u3053\u306e\u95a2\u6570\u306f\u3001inode\u3092\u30ed\u30c3\u30af\u3057\uff08\u4ed6\u306e\u30d7\u30ed\u30bb\u30b9\u304c\u540c\u3058inode\u306b\u5bfe\u3057\u3066ilock\u51fa\u6765\u306a\u3044\u3088\u3046\u306b\u3059\u308b\u305f\u3081\u306b\uff09\u3001\u305d\u3057\u3066\u8aad\u307f\u53d6\u308a\u6e08\u307f\u3067\u306a\u3051\u308c\u3070\u3001\u30c7\u30a3\u30b9\u30af\u304b\u3089inode\u3092\u8aad\u307f\u53d6\u308b\u3002
\niunlock\u95a2\u6570\u306f\u3001inode\u306b\u5bfe\u3059\u308b\u30ed\u30c3\u30af\u3092\u89e3\u653e\u3059\u308b\u3002
\ninode\u30dd\u30a4\u30f3\u30bf\u306e\u7372\u5f97\u3092\u3001\u30ed\u30c3\u30af\u304b\u3089\u5206\u96e2\u3059\u308b\u3053\u3068\u306f\u3001\u3044\u304f\u3064\u304b\u306e\u5834\u5408\u306b\u30c7\u30c3\u30c9\u30ed\u30c3\u30af\u3092\u907f\u3051\u308b\u52a9\u3051\u306b\u306a\u308b\u3002
\n\u4f8b\u3048\u3070\u3001\u30c7\u30a3\u30ec\u30af\u30c8\u30ea\u3092\u63a2\u7d22\u3059\u308b\u5834\u5408\u3067\u3042\u308b\u3002
\n\u8907\u6570\u306e\u30d7\u30ed\u30bb\u30b9\u306f\u3001iget\u95a2\u6570\u306b\u3088\u3063\u3066\u8fd4\u3055\u308c\u305f\u3042\u308binode\u3078\u306eC\u30dd\u30a4\u30f3\u30bf\u3092\u4fdd\u6301\u3059\u308b\u3053\u3068\u304c\u51fa\u6765\u308b\u304c\u3001\u4e00\u5ea6\u306b\u4e00\u3064\u306e\u30d7\u30ed\u30bb\u30b9\u3060\u3051\u304c\u305d\u306einode\u3092\u30ed\u30c3\u30af\u51fa\u6765\u308b\u3002<\/p>\n
inode\u30ad\u30e3\u30c3\u30b7\u30e5\u306f\u3001\u30ab\u30fc\u30cd\u30eb\u306e\u30b3\u30fc\u30c9\u3084C\u30dd\u30a4\u30f3\u30bf\u3092\u4fdd\u6301\u3059\u308b\u30c7\u30fc\u30bf\u69cb\u9020\u306e\u305f\u3081\u306b\u3001inode\u3092\u30ad\u30e3\u30c3\u30b7\u30e5\u3059\u308b\u306e\u307f\u3067\u3042\u308b\u3002
\ninode\u30ad\u30e3\u30c3\u30b7\u30e5\u306e\u4e3b\u306a\u5f79\u5272\u306f\u3001\u8907\u6570\u306e\u30d7\u30ed\u30bb\u30b9\u306b\u3088\u308b\u30a2\u30af\u30bb\u30b9\u3092\u78ba\u5b9f\u306b\u540c\u671f\u5316\u3059\u308b\u3053\u3068\u3067\u3042\u308a\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u3059\u308b\u3053\u3068\u3067\u306f\u306a\u3044\u3002
\n\u3042\u308binode\u304c\u983b\u7e41\u306b\u5229\u7528\u3055\u308c\u308b\u5834\u5408\u3001inode\u30ad\u30e3\u30c3\u30b7\u30e5\u306b\u3088\u3063\u3066\u30ad\u30e3\u30c3\u30b7\u30e5\u3055\u308c\u306a\u304f\u3066\u3082\u3001\u30d0\u30c3\u30d5\u30a1\u30ad\u30e3\u30c3\u30b7\u30e5\u306b\u3088\u3063\u3066\u3001\u30e1\u30e2\u30ea\u4e0a\u306b\u9069\u5207\u306b\u4fdd\u6301\u3055\u308c\u308b\u3002<\/p>\n
\u611f\u60f3<\/h3>\n
inode\u306e\u6982\u8981\u3067\u3059\u3002
\n\u30d8\u30c3\u30c0\u306e\u30bd\u30fc\u30b9\u306f\u8f09\u305b\u3066\u307e\u3059\u304c\u3001\u5404\u95a2\u6570\u306e\u30bd\u30fc\u30b9\u306f\u5f8c\u306e\u7bc0\u3067\u8aac\u660e\u304c\u3042\u308b\u306f\u305a\u306a\u306e\u3067\u3001\u4eca\u56de\u306f\u8f09\u305b\u3066\u307e\u305b\u3093\u3002<\/p>\n
\u30e1\u30e2\u30ea\u4e0a\u306binode\u306e\u8907\u88fd\u3092\u6301\u3064\u306e\u306f\u3001\u4e3b\u306b\u30ad\u30e3\u30c3\u30b7\u30e5\u306e\u70ba\u3067\u306f\u306a\u304f\u3001\u540c\u3058inode\u306b\u5bfe\u3059\u308b\u30a2\u30af\u30bb\u30b9\u3092\u540c\u671f\u5316\u3059\u308b\u76ee\u7684\u306e\u70ba\u306e\u3088\u3046\u3067\u3059\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[32],"tags":[405],"class_list":["post-1627","post","type-post","status-publish","format-standard","hentry","category-tech","tag-xv6"],"_links":{"self":[{"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/posts\/1627","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/comments?post=1627"}],"version-history":[{"count":0,"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/posts\/1627\/revisions"}],"wp:attachment":[{"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/media?parent=1627"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/categories?post=1627"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/peta.okechan.net\/blog\/wp-json\/wp\/v2\/tags?post=1627"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}