xref: /qemu/nbd/nbd-internal.h (revision b30d1886)
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 /* #define DEBUG_NBD */
35 
36 #ifdef DEBUG_NBD
37 #define DEBUG_NBD_PRINT 1
38 #else
39 #define DEBUG_NBD_PRINT 0
40 #endif
41 
42 #define TRACE(msg, ...) do { \
43     if (DEBUG_NBD_PRINT) { \
44         LOG(msg, ## __VA_ARGS__); \
45     } \
46 } while (0)
47 
48 #define LOG(msg, ...) do { \
49     fprintf(stderr, "%s:%s():L%d: " msg "\n", \
50             __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
51 } while (0)
52 
53 /* This is all part of the "official" NBD API.
54  *
55  * The most up-to-date documentation is available at:
56  * https://github.com/yoe/nbd/blob/master/doc/proto.md
57  */
58 
59 #define NBD_REQUEST_SIZE        (4 + 2 + 2 + 8 + 8 + 4)
60 #define NBD_REPLY_SIZE          (4 + 4 + 8)
61 #define NBD_REQUEST_MAGIC       0x25609513
62 #define NBD_REPLY_MAGIC         0x67446698
63 #define NBD_OPTS_MAGIC          0x49484156454F5054LL
64 #define NBD_CLIENT_MAGIC        0x0000420281861253LL
65 #define NBD_REP_MAGIC           0x0003e889045565a9LL
66 
67 #define NBD_SET_SOCK            _IO(0xab, 0)
68 #define NBD_SET_BLKSIZE         _IO(0xab, 1)
69 #define NBD_SET_SIZE            _IO(0xab, 2)
70 #define NBD_DO_IT               _IO(0xab, 3)
71 #define NBD_CLEAR_SOCK          _IO(0xab, 4)
72 #define NBD_CLEAR_QUE           _IO(0xab, 5)
73 #define NBD_PRINT_DEBUG         _IO(0xab, 6)
74 #define NBD_SET_SIZE_BLOCKS     _IO(0xab, 7)
75 #define NBD_DISCONNECT          _IO(0xab, 8)
76 #define NBD_SET_TIMEOUT         _IO(0xab, 9)
77 #define NBD_SET_FLAGS           _IO(0xab, 10)
78 
79 #define NBD_OPT_EXPORT_NAME     (1)
80 #define NBD_OPT_ABORT           (2)
81 #define NBD_OPT_LIST            (3)
82 #define NBD_OPT_PEEK_EXPORT     (4)
83 #define NBD_OPT_STARTTLS        (5)
84 
85 /* NBD errors are based on errno numbers, so there is a 1:1 mapping,
86  * but only a limited set of errno values is specified in the protocol.
87  * Everything else is squashed to EINVAL.
88  */
89 #define NBD_SUCCESS    0
90 #define NBD_EPERM      1
91 #define NBD_EIO        5
92 #define NBD_ENOMEM     12
93 #define NBD_EINVAL     22
94 #define NBD_ENOSPC     28
95 #define NBD_ESHUTDOWN  108
96 
97 static inline ssize_t read_sync(QIOChannel *ioc, void *buffer, size_t size)
98 {
99     struct iovec iov = { .iov_base = buffer, .iov_len = size };
100     /* Sockets are kept in blocking mode in the negotiation phase.  After
101      * that, a non-readable socket simply means that another thread stole
102      * our request/reply.  Synchronization is done with recv_coroutine, so
103      * that this is coroutine-safe.
104      */
105     return nbd_wr_syncv(ioc, &iov, 1, size, true);
106 }
107 
108 static inline ssize_t write_sync(QIOChannel *ioc, const void *buffer,
109                                  size_t size)
110 {
111     struct iovec iov = { .iov_base = (void *) buffer, .iov_len = size };
112 
113     return nbd_wr_syncv(ioc, &iov, 1, size, false);
114 }
115 
116 struct NBDTLSHandshakeData {
117     GMainLoop *loop;
118     bool complete;
119     Error *error;
120 };
121 
122 
123 void nbd_tls_handshake(QIOTask *task,
124                        void *opaque);
125 
126 #endif
127