1/*
2 * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL.
3 * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
4 *            Made nbd_end_request() use the io_request_lock
5 * 2001 Copyright (C) Steven Whitehouse
6 *            New nbd_end_request() for compatibility with new linux block
7 *            layer code.
8 * 2003/06/24 Louis D. Langholtz <ldl@aros.net>
9 *            Removed unneeded blksize_bits field from nbd_device struct.
10 *            Cleanup PARANOIA usage & code.
11 * 2004/02/19 Paul Clements
12 *            Removed PARANOIA, plus various cleanup and comments
13 */
14
15#ifndef _UAPILINUX_NBD_H
16#define _UAPILINUX_NBD_H
17
18#include <linux/types.h>
19
20#define NBD_SET_SOCK	_IO( 0xab, 0 )
21#define NBD_SET_BLKSIZE	_IO( 0xab, 1 )
22#define NBD_SET_SIZE	_IO( 0xab, 2 )
23#define NBD_DO_IT	_IO( 0xab, 3 )
24#define NBD_CLEAR_SOCK	_IO( 0xab, 4 )
25#define NBD_CLEAR_QUE	_IO( 0xab, 5 )
26#define NBD_PRINT_DEBUG	_IO( 0xab, 6 )
27#define NBD_SET_SIZE_BLOCKS	_IO( 0xab, 7 )
28#define NBD_DISCONNECT  _IO( 0xab, 8 )
29#define NBD_SET_TIMEOUT _IO( 0xab, 9 )
30#define NBD_SET_FLAGS   _IO( 0xab, 10)
31
32enum {
33	NBD_CMD_READ = 0,
34	NBD_CMD_WRITE = 1,
35	NBD_CMD_DISC = 2,
36	NBD_CMD_FLUSH = 3,
37	NBD_CMD_TRIM = 4
38};
39
40/* values for flags field */
41#define NBD_FLAG_HAS_FLAGS    (1 << 0) /* nbd-server supports flags */
42#define NBD_FLAG_READ_ONLY    (1 << 1) /* device is read-only */
43#define NBD_FLAG_SEND_FLUSH   (1 << 2) /* can flush writeback cache */
44/* there is a gap here to match userspace */
45#define NBD_FLAG_SEND_TRIM    (1 << 5) /* send trim/discard */
46
47#define nbd_cmd(req) ((req)->cmd[0])
48
49/* userspace doesn't need the nbd_device structure */
50
51/* These are sent over the network in the request/reply magic fields */
52
53#define NBD_REQUEST_MAGIC 0x25609513
54#define NBD_REPLY_MAGIC 0x67446698
55/* Do *not* use magics: 0x12560953 0x96744668. */
56
57/*
58 * This is the packet used for communication between client and
59 * server. All data are in network byte order.
60 */
61struct nbd_request {
62	__be32 magic;
63	__be32 type;	/* == READ || == WRITE 	*/
64	char handle[8];
65	__be64 from;
66	__be32 len;
67} __attribute__((packed));
68
69/*
70 * This is the reply packet that nbd-server sends back to the client after
71 * it has completed an I/O request (or an error occurs).
72 */
73struct nbd_reply {
74	__be32 magic;
75	__be32 error;		/* 0 = ok, else error	*/
76	char handle[8];		/* handle you got from request	*/
77};
78#endif /* _UAPILINUX_NBD_H */
79