xv6-65oo2/kernel/file.h
Robert Morris a8305b7318 FD_DEVICE
2019-06-13 10:29:27 -04:00

38 lines
876 B
C

struct file {
enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE } type;
int ref; // reference count
char readable;
char writable;
struct pipe *pipe; // FD_PIPE
struct inode *ip; // FD_INODE and FD_DEVICE
uint off; // FD_INODE
short major; // FD_DEVICE
};
// in-memory copy of an inode
struct inode {
uint dev; // Device number
uint inum; // Inode number
int ref; // Reference count
struct sleeplock lock; // protects everything below here
int valid; // inode has been read from disk?
short type; // copy of disk inode
short major;
short minor;
short nlink;
uint size;
uint addrs[NDIRECT+1];
};
// map major device number to device functions.
struct devsw {
int (*read)(int, uint64, int);
int (*write)(int, uint64, int);
};
extern struct devsw devsw[];
#define CONSOLE 1