1 /* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */
2 /*
3 * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL.
4 * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
5 * Made nbd_end_request() use the io_request_lock
6 * 2001 Copyright (C) Steven Whitehouse
7 * New nbd_end_request() for compatibility with new linux block
8 * layer code.
9 * 2003/06/24 Louis D. Langholtz <ldl@aros.net>
10 * Removed unneeded blksize_bits field from nbd_device struct.
11 * Cleanup PARANOIA usage & code.
12 * 2004/02/19 Paul Clements
13 * Removed PARANOIA, plus various cleanup and comments
14 */
15
16 #ifndef _UAPILINUX_NBD_H
17 #define _UAPILINUX_NBD_H
18
19 #include <linux/types.h>
20
21 #define NBD_SET_SOCK _IO( 0xab, 0 )
22 #define NBD_SET_BLKSIZE _IO( 0xab, 1 )
23 #define NBD_SET_SIZE _IO( 0xab, 2 )
24 #define NBD_DO_IT _IO( 0xab, 3 )
25 #define NBD_CLEAR_SOCK _IO( 0xab, 4 )
26 #define NBD_CLEAR_QUE _IO( 0xab, 5 )
27 #define NBD_PRINT_DEBUG _IO( 0xab, 6 )
28 #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 )
29 #define NBD_DISCONNECT _IO( 0xab, 8 )
30 #define NBD_SET_TIMEOUT _IO( 0xab, 9 )
31 #define NBD_SET_FLAGS _IO( 0xab, 10)
32
33 enum {
34 NBD_CMD_READ = 0,
35 NBD_CMD_WRITE = 1,
36 NBD_CMD_DISC = 2,
37 NBD_CMD_FLUSH = 3,
38 NBD_CMD_TRIM = 4
39 };
40
41 /* values for flags field, these are server interaction specific. */
42 #define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */
43 #define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */
44 #define NBD_FLAG_SEND_FLUSH (1 << 2) /* can flush writeback cache */
45 #define NBD_FLAG_SEND_FUA (1 << 3) /* send FUA (forced unit access) */
46 /* there is a gap here to match userspace */
47 #define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */
48 #define NBD_FLAG_CAN_MULTI_CONN (1 << 8) /* Server supports multiple connections per export. */
49
50 /* values for cmd flags in the upper 16 bits of request type */
51 #define NBD_CMD_FLAG_FUA (1 << 16) /* FUA (forced unit access) op */
52
53 /* These are client behavior specific flags. */
54 #define NBD_CFLAG_DESTROY_ON_DISCONNECT (1 << 0) /* delete the nbd device on
55 disconnect. */
56 #define NBD_CFLAG_DISCONNECT_ON_CLOSE (1 << 1) /* disconnect the nbd device on
57 * close by last opener.
58 */
59
60 /* userspace doesn't need the nbd_device structure */
61
62 /* These are sent over the network in the request/reply magic fields */
63
64 #define NBD_REQUEST_MAGIC 0x25609513
65 #define NBD_REPLY_MAGIC 0x67446698
66 /* Do *not* use magics: 0x12560953 0x96744668. */
67
68 /*
69 * This is the packet used for communication between client and
70 * server. All data are in network byte order.
71 */
72 struct nbd_request {
73 __be32 magic;
74 __be32 type; /* == READ || == WRITE */
75 char handle[8];
76 __be64 from;
77 __be32 len;
78 } __attribute__((packed));
79
80 /*
81 * This is the reply packet that nbd-server sends back to the client after
82 * it has completed an I/O request (or an error occurs).
83 */
84 struct nbd_reply {
85 __be32 magic;
86 __be32 error; /* 0 = ok, else error */
87 char handle[8]; /* handle you got from request */
88 };
89 #endif /* _UAPILINUX_NBD_H */