Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
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#include <linux/wait.h>
41#include <linux/mutex.h>
42
43/* values for flags field */
44#define NBD_READ_ONLY 0x0001
45#define NBD_WRITE_NOCHK 0x0002
46
47struct request;
48
49struct nbd_device {
50 int flags;
51 int harderror; /* Code of hard error */
52 struct socket * sock;
53 struct file * file; /* If == NULL, device is not ready, yet */
54 int magic;
55
56 spinlock_t queue_lock;
57 struct list_head queue_head;/* Requests are added here... */
58 struct request *active_req;
59 wait_queue_head_t active_wq;
60
61 struct mutex tx_lock;
62 struct gendisk *disk;
63 int blksize;
64 u64 bytesize;
65};
66
67#endif
68
69/* These are sent over the network in the request/reply magic fields */
70
71#define NBD_REQUEST_MAGIC 0x25609513
72#define NBD_REPLY_MAGIC 0x67446698
73/* Do *not* use magics: 0x12560953 0x96744668. */
74
75/*
76 * This is the packet used for communication between client and
77 * server. All data are in network byte order.
78 */
79struct nbd_request {
80 u32 magic;
81 u32 type; /* == READ || == WRITE */
82 char handle[8];
83 u64 from;
84 u32 len;
85}
86#ifdef __GNUC__
87 __attribute__ ((packed))
88#endif
89;
90
91/*
92 * This is the reply packet that nbd-server sends back to the client after
93 * it has completed an I/O request (or an error occurs).
94 */
95struct nbd_reply {
96 u32 magic;
97 u32 error; /* 0 = ok, else error */
98 char handle[8]; /* handle you got from request */
99};
100#endif