xref: /openbmc/qemu/nbd/nbd-internal.h (revision dc5bd18f)
1 /*
2  * NBD Internal Declarations
3  *
4  * Copyright (C) 2016 Red Hat, Inc.
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/coroutine.h"
17 #include "qemu/iov.h"
18 
19 #ifndef _WIN32
20 #include <sys/ioctl.h>
21 #endif
22 #if defined(__sun__) || defined(__HAIKU__)
23 #include <sys/ioccom.h>
24 #endif
25 
26 #ifdef __linux__
27 #include <linux/fs.h>
28 #endif
29 
30 #include "qemu/bswap.h"
31 #include "qemu/queue.h"
32 #include "qemu/main-loop.h"
33 
34 /* This is all part of the "official" NBD API.
35  *
36  * The most up-to-date documentation is available at:
37  * https://github.com/yoe/nbd/blob/master/doc/proto.md
38  */
39 
40 /* Size of all NBD_OPT_*, without payload */
41 #define NBD_REQUEST_SIZE            (4 + 2 + 2 + 8 + 8 + 4)
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_REQUEST_MAGIC           0x25609513
50 #define NBD_OPTS_MAGIC              0x49484156454F5054LL
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_read_eof
67  * Tries to read @size bytes from @ioc.
68  * Returns 1 on success
69  *         0 on eof, when no data was read (errp is not set)
70  *         negative errno on failure (errp is set)
71  */
72 static inline int nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size,
73                                Error **errp)
74 {
75     int ret;
76 
77     assert(size);
78     ret = qio_channel_read_all_eof(ioc, buffer, size, errp);
79     if (ret < 0) {
80         ret = -EIO;
81     }
82     return ret;
83 }
84 
85 /* nbd_write
86  * Writes @size bytes to @ioc. Returns 0 on success.
87  */
88 static inline int nbd_write(QIOChannel *ioc, const void *buffer, size_t size,
89                             Error **errp)
90 {
91     return qio_channel_write_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;
92 }
93 
94 struct NBDTLSHandshakeData {
95     GMainLoop *loop;
96     bool complete;
97     Error *error;
98 };
99 
100 
101 void nbd_tls_handshake(QIOTask *task,
102                        void *opaque);
103 const char *nbd_opt_lookup(uint32_t opt);
104 const char *nbd_rep_lookup(uint32_t rep);
105 const char *nbd_info_lookup(uint16_t info);
106 const char *nbd_cmd_lookup(uint16_t info);
107 const char *nbd_err_lookup(int err);
108 
109 int nbd_drop(QIOChannel *ioc, size_t size, Error **errp);
110 
111 #endif
112