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/*
* This file has definitions for some important file table
* structures etc.
*/
#ifndef _FS_H
#define _FS_H
#include <sys/types.h>
/* devices are as follows: (same as minix, so we can use the minix
* file system. These are major numbers.)
*
* 0 - unused (nodev)
* 1 - /dev/mem
* 2 - /dev/fd
* 3 - /dev/hd
* 4 - /dev/ttyx
* 5 - /dev/tty
* 6 - /dev/lp
* 7 - unnamed pipes
*/
#define IS_SEEKABLE(x) ((x)>=1 && (x)<=3)
#define READ 0
#define WRITE 1
#define READA 2 /* read-ahead - don't pause */
#define WRITEA 3 /* "write-ahead" - silly, but somewhat useful */
void buffer_init(long buffer_end);
#define MAJOR(a) (((unsigned)(a))>>8)
#define MINOR(a) ((a)&0xff)
#define NAME_LEN 14
#define ROOT_INO 1
#define I_MAP_SLOTS 8
#define Z_MAP_SLOTS 8
#define SUPER_MAGIC 0x137F
#define NR_OPEN 20
#define NR_INODE 32
#define NR_FILE 64
#define NR_SUPER 8
#define NR_HASH 307
#define NR_BUFFERS nr_buffers
#define BLOCK_SIZE 1024
#define BLOCK_SIZE_BITS 10
#ifndef NULL
#define NULL ((void *) 0)
#endif
#define INODES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct d_inode)))
#define DIR_ENTRIES_PER_BLOCK ((BLOCK_SIZE)/(sizeof (struct dir_entry)))
#define PIPE_HEAD(inode) ((inode).i_zone[0])
#define PIPE_TAIL(inode) ((inode).i_zone[1])
#define PIPE_SIZE(inode) ((PIPE_HEAD(inode)-PIPE_TAIL(inode))&(PAGE_SIZE-1))
#define PIPE_EMPTY(inode) (PIPE_HEAD(inode)==PIPE_TAIL(inode))
#define PIPE_FULL(inode) (PIPE_SIZE(inode)==(PAGE_SIZE-1))
#define INC_PIPE(head) \
__asm__("incl %0\n\tandl $4095,%0"::"m" (head))
typedef char buffer_block[BLOCK_SIZE];
struct buffer_head {
char * b_data; /* pointer to data block (1024 bytes) */
unsigned long b_blocknr; /* block number */
unsigned short b_dev; /* device (0 = free) */
unsigned char b_uptodate;
unsigned char b_dirt; /* 0-clean,1-dirty */
unsigned char b_count; /* users using this block */
unsigned char b_lock; /* 0 - ok, 1 -locked */
struct task_struct * b_wait;
struct buffer_head * b_prev;
struct buffer_head * b_next;
struct buffer_head * b_prev_free;
struct buffer_head * b_next_free;
};
struct d_inode {
unsigned short i_mode;
unsigned short i_uid;
unsigned long i_size;
unsigned long i_time;
unsigned char i_gid;
unsigned char i_nlinks;
unsigned short i_zone[9];
};
struct m_inode {
unsigned short i_mode;
unsigned short i_uid;
unsigned long i_size;
unsigned long i_mtime;
unsigned char i_gid;
unsigned char i_nlinks;
unsigned short i_zone[9];
/* these are in memory also */
struct task_struct * i_wait;
unsigned long i_atime;
unsigned long i_ctime;
unsigned short i_dev;
unsigned short i_num;
unsigned short i_count;
unsigned char i_lock;
unsigned char i_dirt;
unsigned char i_pipe;
unsigned char i_mount;
unsigned char i_seek;
unsigned char i_update;
};
struct file {
unsigned short f_mode;
unsigned short f_flags;
unsigned short f_count;
struct m_inode * f_inode;
off_t f_pos;
};
struct super_block {
unsigned short s_ninodes;
unsigned short s_nzones;
unsigned short s_imap_blocks;
unsigned short s_zmap_blocks;
unsigned short s_firstdatazone;
unsigned short s_log_zone_size;
unsigned long s_max_size;
unsigned short s_magic;
/* These are only in memory */
struct buffer_head * s_imap[8];
struct buffer_head * s_zmap[8];
unsigned short s_dev;
struct m_inode * s_isup;
struct m_inode * s_imount;
unsigned long s_time;
struct task_struct * s_wait;
unsigned char s_lock;
unsigned char s_rd_only;
unsigned char s_dirt;
};
struct d_super_block {
unsigned short s_ninodes;
unsigned short s_nzones;
unsigned short s_imap_blocks;
unsigned short s_zmap_blocks;
unsigned short s_firstdatazone;
unsigned short s_log_zone_size;
unsigned long s_max_size;
unsigned short s_magic;
};
struct dir_entry {
unsigned short inode;
char name[NAME_LEN];
};
extern struct m_inode inode_table[NR_INODE];
extern struct file file_table[NR_FILE];
extern struct super_block super_block[NR_SUPER];
extern struct buffer_head * start_buffer;
extern int nr_buffers;
extern void check_disk_change(int dev);
extern int floppy_change(unsigned int nr);
extern int ticks_to_floppy_on(unsigned int dev);
extern void floppy_on(unsigned int dev);
extern void floppy_off(unsigned int dev);
extern void truncate(struct m_inode * inode);
extern void sync_inodes(void);
extern void wait_on(struct m_inode * inode);
extern int bmap(struct m_inode * inode,int block);
extern int create_block(struct m_inode * inode,int block);
extern struct m_inode * namei(const char * pathname);
extern int open_namei(const char * pathname, int flag, int mode,
struct m_inode ** res_inode);
extern void iput(struct m_inode * inode);
extern struct m_inode * iget(int dev,int nr);
extern struct m_inode * get_empty_inode(void);
extern struct m_inode * get_pipe_inode(void);
extern struct buffer_head * get_hash_table(int dev, int block);
extern struct buffer_head * getblk(int dev, int block);
extern void ll_rw_block(int rw, struct buffer_head * bh);
extern void brelse(struct buffer_head * buf);
extern struct buffer_head * bread(int dev,int block);
extern void bread_page(unsigned long addr,int dev,int b[4]);
extern struct buffer_head * breada(int dev,int block,...);
extern int new_block(int dev);
extern void free_block(int dev, int block);
extern struct m_inode * new_inode(int dev);
extern void free_inode(struct m_inode * inode);
extern int sync_dev(int dev);
extern struct super_block * get_super(int dev);
extern int ROOT_DEV;
extern void mount_root(void);
#endif
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