kern

annotate src/fs.h @ 90:7ff2b4971216

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started work on the filesystem
author John Tsiombikas <nuclear@member.fsf.org>
date Fri, 09 Dec 2011 13:44:15 +0200
parents 2f555c81ae67
children f83f50c17c3b
rev   line source
nuclear@88 1 #ifndef FS_H_
nuclear@88 2 #define FS_H_
nuclear@88 3
nuclear@90 4 #include <inttypes.h>
nuclear@90 5
nuclear@90 6 #define MAGIC 0xccf5ccf5
nuclear@90 7 #define BLKSZ 1024
nuclear@90 8
nuclear@90 9 #define SECT_TO_BLK(x) ((x) / (BLKSZ / 512))
nuclear@90 10
nuclear@90 11 #define DEV_MAJOR(dev) (((dev) >> 8) & 0xff)
nuclear@90 12 #define DEV_MINOR(dev) ((dev) & 0xff)
nuclear@90 13
nuclear@90 14
nuclear@90 15 typedef uint32_t dev_t;
nuclear@90 16 typedef uint32_t blkid;
nuclear@90 17
nuclear@90 18 struct superblock {
nuclear@90 19 uint32_t magic; /* magic number */
nuclear@90 20 int ver; /* filesystem version */
nuclear@90 21 int blksize; /* only BLKSZ supported at the moment */
nuclear@90 22
nuclear@90 23 /* total number of blocks */
nuclear@90 24 unsigned int num_blocks;
nuclear@90 25 /* inode allocation bitmap start and count */
nuclear@90 26 blkid ibm_start;
nuclear@90 27 unsigned int ibm_count;
nuclear@90 28 /* inode table start and count */
nuclear@90 29 blkid itbl_start;
nuclear@90 30 unsigned int itbl_count;
nuclear@90 31 /* data block allocation bitmap start and count */
nuclear@90 32 blkid dbm_start;
nuclear@90 33 unsigned int dbm_count;
nuclear@90 34 /* data blocks start and count */
nuclear@90 35 blkid data_start;
nuclear@90 36 unsigned int data_count;
nuclear@90 37
nuclear@90 38 int root_ino; /* root direcotry inode */
nuclear@90 39
nuclear@90 40 /* the following are valid only at runtime, ignored on disk */
nuclear@90 41 uint32_t *ibm; /* memory inode bitmap */
nuclear@90 42 uint32_t *dbm; /* memory datablock bitmap */
nuclear@90 43
nuclear@90 44 } __attribute__((packed));
nuclear@90 45
nuclear@90 46
nuclear@90 47 /* 20 direct blocks + 10 attributes + 2 indirect = 128 bytes per inode */
nuclear@90 48 #define NDIRBLK 20
nuclear@90 49 struct inode {
nuclear@90 50 int ino;
nuclear@90 51 int uid, gid, mode;
nuclear@90 52 int nlink;
nuclear@90 53 dev_t dev;
nuclear@90 54 uint32_t atime, ctime, mtime;
nuclear@90 55 uint32_t size;
nuclear@90 56 blkid blk[NDIRBLK]; /* direct blocks */
nuclear@90 57 blkid ind; /* indirect */
nuclear@90 58 blkid dind; /* double-indirect */
nuclear@90 59 } __attribute__((packed));
nuclear@90 60
nuclear@90 61
nuclear@90 62 int sys_mount(char *mntpt, char *devname, unsigned int flags);
nuclear@90 63 int sys_umount(char *devname);
nuclear@90 64
nuclear@90 65 int sys_open(char *pathname, int flags, unsigned int mode);
nuclear@90 66 int sys_close(int fd);
nuclear@90 67
nuclear@90 68 int sys_read(int fd, void *buf, int sz);
nuclear@90 69 int sys_write(int fd, void *buf, int sz);
nuclear@90 70 long sys_lseek(int fd, long offs, int from);
nuclear@90 71
nuclear@90 72 int lookup_path(const char *path);
nuclear@88 73
nuclear@89 74
nuclear@88 75 #endif /* FS_H_ */