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/*
* 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL.
* 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
* Made nbd_end_request() use the io_request_lock
* 2001 Copyright (C) Steven Whitehouse
* New nbd_end_request() for compatibility with new linux block
* layer code.
* 2003/06/24 Louis D. Langholtz <ldl@aros.net>
* Removed unneeded blksize_bits field from nbd_device struct.
* Cleanup PARANOIA usage & code.
* 2004/02/19 Paul Clements
* Removed PARANOIA, plus various cleanup and comments
*/
#ifndef LINUX_NBD_H
#define LINUX_NBD_H
#define NBD_SET_SOCK _IO( 0xab, 0 )
#define NBD_SET_BLKSIZE _IO( 0xab, 1 )
#define NBD_SET_SIZE _IO( 0xab, 2 )
#define NBD_DO_IT _IO( 0xab, 3 )
#define NBD_CLEAR_SOCK _IO( 0xab, 4 )
#define NBD_CLEAR_QUE _IO( 0xab, 5 )
#define NBD_PRINT_DEBUG _IO( 0xab, 6 )
#define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 )
#define NBD_DISCONNECT _IO( 0xab, 8 )
enum {
NBD_CMD_READ = 0,
NBD_CMD_WRITE = 1,
NBD_CMD_DISC = 2
};
#define nbd_cmd(req) ((req)->cmd[0])
#define MAX_NBD 128
/* userspace doesn't need the nbd_device structure */
#ifdef __KERNEL__
#include <linux/wait.h>
/* values for flags field */
#define NBD_READ_ONLY 0x0001
#define NBD_WRITE_NOCHK 0x0002
struct request;
struct nbd_device {
int flags;
int harderror; /* Code of hard error */
struct socket * sock;
struct file * file; /* If == NULL, device is not ready, yet */
int magic;
spinlock_t queue_lock;
struct list_head queue_head;/* Requests are added here... */
struct request *active_req;
wait_queue_head_t active_wq;
struct semaphore tx_lock;
struct gendisk *disk;
int blksize;
u64 bytesize;
};
#endif
/* These are sent over the network in the request/reply magic fields */
#define NBD_REQUEST_MAGIC 0x25609513
#define NBD_REPLY_MAGIC 0x67446698
/* Do *not* use magics: 0x12560953 0x96744668. */
/*
* This is the packet used for communication between client and
* server. All data are in network byte order.
*/
struct nbd_request {
u32 magic;
u32 type; /* == READ || == WRITE */
char handle[8];
u64 from;
u32 len;
}
#ifdef __GNUC__
__attribute__ ((packed))
#endif
;
/*
* This is the reply packet that nbd-server sends back to the client after
* it has completed an I/O request (or an error occurs).
*/
struct nbd_reply {
u32 magic;
u32 error; /* 0 = ok, else error */
char handle[8]; /* handle you got from request */
};
#endif