minix/servers/vfs/file.h
2012-02-13 16:53:21 +00:00

48 lines
1.8 KiB
C

#ifndef __VFS_FILE_H__
#define __VFS_FILE_H__
/* This is the filp table. It is an intermediary between file descriptors and
* inodes. A slot is free if filp_count == 0.
*/
EXTERN struct filp {
mode_t filp_mode; /* RW bits, telling how file is opened */
int filp_flags; /* flags from open and fcntl */
int filp_state; /* state for crash recovery */
int filp_count; /* how many file descriptors share this slot?*/
struct vnode *filp_vno; /* vnode belonging to this file */
u64_t filp_pos; /* file position */
mutex_t filp_lock; /* lock to gain exclusive access */
struct fproc *filp_softlock; /* if not NULL; this filp didn't lock the
* vnode. Another filp already holds a lock
* for this thread */
/* the following fields are for select() and are owned by the generic
* select() code (i.e., fd-type-specific select() code can't touch these).
*/
int filp_selectors; /* select()ing processes blocking on this fd */
int filp_select_ops; /* interested in these SEL_* operations */
int filp_select_flags; /* Select flags for the filp */
/* following are for fd-type-specific select() */
int filp_pipe_select_ops;
} filp[NR_FILPS];
#define FILP_CLOSED 0 /* filp_mode: associated device closed */
#define FS_NORMAL 0 /* file descriptor can be used normally */
#define FS_NEEDS_REOPEN 1 /* file descriptor needs to be re-opened */
#define FSF_UPDATE 001 /* The driver should be informed about new
* state.
*/
#define FSF_BUSY 002 /* Select operation sent to driver but no
* reply yet.
*/
#define FSF_RD_BLOCK 010 /* Read request is blocking, the driver should
* keep state.
*/
#define FSF_WR_BLOCK 020 /* Write request is blocking */
#define FSF_ERR_BLOCK 040 /* Exception request is blocking */
#define FSF_BLOCKED 070
#endif