xref: /openbmc/qemu/nbd/nbd-internal.h (revision 2b74dd91)
1 /*
2  * NBD Internal Declarations
3  *
4  * Copyright Red Hat
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  */
9 
10 #ifndef NBD_INTERNAL_H
11 #define NBD_INTERNAL_H
12 #include "block/nbd.h"
13 #include "sysemu/block-backend.h"
14 #include "io/channel-tls.h"
15 
16 #include "qemu/iov.h"
17 
18 #ifndef _WIN32
19 #include <sys/ioctl.h>
20 #endif
21 #ifdef HAVE_SYS_IOCCOM_H
22 #include <sys/ioccom.h>
23 #endif
24 
25 #ifdef __linux__
26 #include <linux/fs.h>
27 #endif
28 
29 #include "qemu/bswap.h"
30 
31 /* This is all part of the "official" NBD API.
32  *
33  * The most up-to-date documentation is available at:
34  * https://github.com/yoe/nbd/blob/master/doc/proto.md
35  */
36 
37 /* Size of all compact NBD_CMD_*, without payload */
38 #define NBD_REQUEST_SIZE            (4 + 2 + 2 + 8 + 8 + 4)
39 /* Size of all extended NBD_CMD_*, without payload */
40 #define NBD_EXTENDED_REQUEST_SIZE   (4 + 2 + 2 + 8 + 8 + 8)
41 
42 /* Size of all NBD_REP_* sent in answer to most NBD_OPT_*, without payload */
43 #define NBD_REPLY_SIZE              (4 + 4 + 8)
44 /* Size of reply to NBD_OPT_EXPORT_NAME */
45 #define NBD_REPLY_EXPORT_NAME_SIZE  (8 + 2 + 124)
46 /* Size of oldstyle negotiation */
47 #define NBD_OLDSTYLE_NEGOTIATE_SIZE (8 + 8 + 8 + 4 + 124)
48 
49 #define NBD_INIT_MAGIC              0x4e42444d41474943LL /* ASCII "NBDMAGIC" */
50 #define NBD_OPTS_MAGIC              0x49484156454F5054LL /* ASCII "IHAVEOPT" */
51 #define NBD_CLIENT_MAGIC            0x0000420281861253LL
52 #define NBD_REP_MAGIC               0x0003e889045565a9LL
53 
54 #define NBD_SET_SOCK                _IO(0xab, 0)
55 #define NBD_SET_BLKSIZE             _IO(0xab, 1)
56 #define NBD_SET_SIZE                _IO(0xab, 2)
57 #define NBD_DO_IT                   _IO(0xab, 3)
58 #define NBD_CLEAR_SOCK              _IO(0xab, 4)
59 #define NBD_CLEAR_QUE               _IO(0xab, 5)
60 #define NBD_PRINT_DEBUG             _IO(0xab, 6)
61 #define NBD_SET_SIZE_BLOCKS         _IO(0xab, 7)
62 #define NBD_DISCONNECT              _IO(0xab, 8)
63 #define NBD_SET_TIMEOUT             _IO(0xab, 9)
64 #define NBD_SET_FLAGS               _IO(0xab, 10)
65 
66 /* nbd_write
67  * Writes @size bytes to @ioc. Returns 0 on success.
68  */
69 static inline int nbd_write(QIOChannel *ioc, const void *buffer, size_t size,
70                             Error **errp)
71 {
72     return qio_channel_write_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;
73 }
74 
75 int nbd_drop(QIOChannel *ioc, size_t size, Error **errp);
76 
77 #endif
78