/*
* 1999 Copyright (C) Pavel Machek, [email protected]. 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 <[email protected]>
* 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

#include <linux/types.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 )
#define NBD_SET_TIMEOUT _IO( 0xab, 9 )

enum {
NBD_CMD_READ = 0,
NBD_CMD_WRITE = 1,
NBD_CMD_DISC = 2
};

#define nbd_cmd(req) ((req)->cmd[0])

/* userspace doesn't need the nbd_device structure */

/* 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 {
__be32 magic;
__be32 type; /* == READ || == WRITE */
char handle[8];
__be64 from;
__be32 len;
} __attribute__ ((packed));

/*
* 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 {
__be32 magic;
__be32 error; /* 0 = ok, else error */
char handle[8]; /* handle you got from request */
};
#endif