Network Block Device 2.9.20

nbd.h

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00001 /*
00002  * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL.
00003  * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
00004  *            Made nbd_end_request() use the io_request_lock
00005  * 2001 Copyright (C) Steven Whitehouse
00006  *            New nbd_end_request() for compatibility with new linux block
00007  *            layer code.
00008  * 2003/06/24 Louis D. Langholtz <ldl@aros.net>
00009  *            Removed unneeded blksize_bits field from nbd_device struct.
00010  *            Cleanup PARANOIA usage & code.
00011  * 2004/02/19 Paul Clements
00012  *            Removed PARANOIA, plus various cleanup and comments
00013  */
00014 
00015 #ifndef LINUX_NBD_H
00016 #define LINUX_NBD_H
00017 
00018 //#include <linux/types.h>
00019 
00020 #define NBD_SET_SOCK    _IO( 0xab, 0 )
00021 #define NBD_SET_BLKSIZE _IO( 0xab, 1 )
00022 #define NBD_SET_SIZE    _IO( 0xab, 2 )
00023 #define NBD_DO_IT       _IO( 0xab, 3 )
00024 #define NBD_CLEAR_SOCK  _IO( 0xab, 4 )
00025 #define NBD_CLEAR_QUE   _IO( 0xab, 5 )
00026 #define NBD_PRINT_DEBUG _IO( 0xab, 6 )
00027 #define NBD_SET_SIZE_BLOCKS     _IO( 0xab, 7 )
00028 #define NBD_DISCONNECT  _IO( 0xab, 8 )
00029 #define NBD_SET_TIMEOUT _IO( 0xab, 9 )
00030 
00031 enum {
00032         NBD_CMD_READ = 0,
00033         NBD_CMD_WRITE = 1,
00034         NBD_CMD_DISC = 2
00035 };
00036 
00037 #define nbd_cmd(req) ((req)->cmd[0])
00038 
00039 /* userspace doesn't need the nbd_device structure */
00040 
00041 /* These are sent over the network in the request/reply magic fields */
00042 
00043 #define NBD_REQUEST_MAGIC 0x25609513
00044 #define NBD_REPLY_MAGIC 0x67446698
00045 /* Do *not* use magics: 0x12560953 0x96744668. */
00046 
00047 /*
00048  * This is the packet used for communication between client and
00049  * server. All data are in network byte order.
00050  */
00051 struct nbd_request {
00052         __be32 magic;
00053         __be32 type;    /* == READ || == WRITE  */
00054         char handle[8];
00055         __be64 from;
00056         __be32 len;
00057 } __attribute__ ((packed));
00058 
00059 /*
00060  * This is the reply packet that nbd-server sends back to the client after
00061  * it has completed an I/O request (or an error occurs).
00062  */
00063 struct nbd_reply {
00064         __be32 magic;
00065         __be32 error;           /* 0 = ok, else error   */
00066         char handle[8];         /* handle you got from request  */
00067 };
00068 #endif