blob: d146ca10c0f52449dd528e9fec61be47e0c85221 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Mike Frysingerc751c1d2006-10-11 01:22:11 -070018#include <linux/types.h>
19
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#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 )
Paul Clements7fdfd402007-10-16 23:27:37 -070029#define NBD_SET_TIMEOUT _IO( 0xab, 9 )
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
31enum {
32 NBD_CMD_READ = 0,
33 NBD_CMD_WRITE = 1,
34 NBD_CMD_DISC = 2
35};
36
37#define nbd_cmd(req) ((req)->cmd[0])
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39/* userspace doesn't need the nbd_device structure */
40#ifdef __KERNEL__
41
Herbert Xu4b2f0262006-01-06 00:09:47 -080042#include <linux/wait.h>
Ingo Molnar82d4dc52006-03-23 03:00:38 -080043#include <linux/mutex.h>
Herbert Xu4b2f0262006-01-06 00:09:47 -080044
Linus Torvalds1da177e2005-04-16 15:20:36 -070045/* values for flags field */
46#define NBD_READ_ONLY 0x0001
47#define NBD_WRITE_NOCHK 0x0002
48
Herbert Xu4b2f0262006-01-06 00:09:47 -080049struct request;
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051struct 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;
Herbert Xu4b2f0262006-01-06 00:09:47 -080057
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 spinlock_t queue_lock;
Laurent Vivier48cf6062008-04-29 01:02:46 -070059 struct list_head queue_head; /* Requests waiting result */
Herbert Xu4b2f0262006-01-06 00:09:47 -080060 struct request *active_req;
61 wait_queue_head_t active_wq;
Laurent Vivier48cf6062008-04-29 01:02:46 -070062 struct list_head waiting_queue; /* Requests to be sent */
63 wait_queue_head_t waiting_wq;
Herbert Xu4b2f0262006-01-06 00:09:47 -080064
Ingo Molnar82d4dc52006-03-23 03:00:38 -080065 struct mutex tx_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 struct gendisk *disk;
67 int blksize;
68 u64 bytesize;
Paul Clements6b39bb62006-12-06 20:40:53 -080069 pid_t pid; /* pid of nbd-client, if attached */
Paul Clements7fdfd402007-10-16 23:27:37 -070070 int xmit_timeout;
Linus Torvalds1da177e2005-04-16 15:20:36 -070071};
72
73#endif
74
75/* These are sent over the network in the request/reply magic fields */
76
77#define NBD_REQUEST_MAGIC 0x25609513
78#define NBD_REPLY_MAGIC 0x67446698
79/* Do *not* use magics: 0x12560953 0x96744668. */
80
81/*
82 * This is the packet used for communication between client and
83 * server. All data are in network byte order.
84 */
85struct nbd_request {
Alexey Dobriyan4ad3bcf2006-06-25 05:48:13 -070086 __be32 magic;
87 __be32 type; /* == READ || == WRITE */
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 char handle[8];
Alexey Dobriyan4ad3bcf2006-06-25 05:48:13 -070089 __be64 from;
90 __be32 len;
Changli Gao09cd2b92010-08-22 17:25:05 +000091} __attribute__((packed));
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
93/*
94 * This is the reply packet that nbd-server sends back to the client after
95 * it has completed an I/O request (or an error occurs).
96 */
97struct nbd_reply {
Alexey Dobriyan4ad3bcf2006-06-25 05:48:13 -070098 __be32 magic;
99 __be32 error; /* 0 = ok, else error */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 char handle[8]; /* handle you got from request */
101};
102#endif