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#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
30enum {
31 NBD_CMD_READ = 0,
32 NBD_CMD_WRITE = 1,
33 NBD_CMD_DISC = 2
34};
35
36#define nbd_cmd(req) ((req)->cmd[0])
37#define MAX_NBD 128
38
39/* userspace doesn't need the nbd_device structure */
40#ifdef __KERNEL__
41
42#include <linux/wait.h>
43#include <linux/mutex.h>
44
45/* values for flags field */
46#define NBD_READ_ONLY 0x0001
47#define NBD_WRITE_NOCHK 0x0002
48
49struct request;
50
51struct nbd_device {
52 int flags;
53 int harderror; /* Code of hard error */
54 struct socket * sock;
55 struct file * file; /* If == NULL, device is not ready, yet */
56 int magic;
57
58 spinlock_t queue_lock;
59 struct list_head queue_head;/* Requests are added here... */
60 struct request *active_req;
61 wait_queue_head_t active_wq;
62
63 struct mutex tx_lock;
64 struct gendisk *disk;
65 int blksize;
66 u64 bytesize;
67 pid_t pid; /* pid of nbd-client, if attached */
68};
69
70#endif
71
72/* These are sent over the network in the request/reply magic fields */
73
74#define NBD_REQUEST_MAGIC 0x25609513
75#define NBD_REPLY_MAGIC 0x67446698
76/* Do *not* use magics: 0x12560953 0x96744668. */
77
78/*
79 * This is the packet used for communication between client and
80 * server. All data are in network byte order.
81 */
82struct nbd_request {
83 __be32 magic;
84 __be32 type; /* == READ || == WRITE */
85 char handle[8];
86 __be64 from;
87 __be32 len;
88}
89#ifdef __GNUC__
90 __attribute__ ((packed))
91#endif
92;
93
94/*
95 * This is the reply packet that nbd-server sends back to the client after
96 * it has completed an I/O request (or an error occurs).
97 */
98struct nbd_reply {
99 __be32 magic;
100 __be32 error; /* 0 = ok, else error */
101 char handle[8]; /* handle you got from request */
102};
103#endif