Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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 LINUX_NBD_H
16#define LINUX_NBD_H
17
18#define NBD_SET_SOCK _IO( 0xab, 0 )
19#define NBD_SET_BLKSIZE _IO( 0xab, 1 )
20#define NBD_SET_SIZE _IO( 0xab, 2 )
21#define NBD_DO_IT _IO( 0xab, 3 )
22#define NBD_CLEAR_SOCK _IO( 0xab, 4 )
23#define NBD_CLEAR_QUE _IO( 0xab, 5 )
24#define NBD_PRINT_DEBUG _IO( 0xab, 6 )
25#define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 )
26#define NBD_DISCONNECT _IO( 0xab, 8 )
27
28enum {
29 NBD_CMD_READ = 0,
30 NBD_CMD_WRITE = 1,
31 NBD_CMD_DISC = 2
32};
33
34#define nbd_cmd(req) ((req)->cmd[0])
35#define MAX_NBD 128
36
37/* userspace doesn't need the nbd_device structure */
38#ifdef __KERNEL__
39
40/* values for flags field */
41#define NBD_READ_ONLY 0x0001
42#define NBD_WRITE_NOCHK 0x0002
43
44struct nbd_device {
45 int flags;
46 int harderror; /* Code of hard error */
47 struct socket * sock;
48 struct file * file; /* If == NULL, device is not ready, yet */
49 int magic;
50 spinlock_t queue_lock;
51 struct list_head queue_head;/* Requests are added here... */
52 struct semaphore tx_lock;
53 struct gendisk *disk;
54 int blksize;
55 u64 bytesize;
56};
57
58#endif
59
60/* These are sent over the network in the request/reply magic fields */
61
62#define NBD_REQUEST_MAGIC 0x25609513
63#define NBD_REPLY_MAGIC 0x67446698
64/* Do *not* use magics: 0x12560953 0x96744668. */
65
66/*
67 * This is the packet used for communication between client and
68 * server. All data are in network byte order.
69 */
70struct nbd_request {
71 u32 magic;
72 u32 type; /* == READ || == WRITE */
73 char handle[8];
74 u64 from;
75 u32 len;
76}
77#ifdef __GNUC__
78 __attribute__ ((packed))
79#endif
80;
81
82/*
83 * This is the reply packet that nbd-server sends back to the client after
84 * it has completed an I/O request (or an error occurs).
85 */
86struct nbd_reply {
87 u32 magic;
88 u32 error; /* 0 = ok, else error */
89 char handle[8]; /* handle you got from request */
90};
91#endif