xref: /openbmc/qemu/nbd/nbd-internal.h (revision 890ad550)
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 #include <errno.h>
20 #include <string.h>
21 #ifndef _WIN32
22 #include <sys/ioctl.h>
23 #endif
24 #if defined(__sun__) || defined(__HAIKU__)
25 #include <sys/ioccom.h>
26 #endif
27 #include <ctype.h>
28 #include <inttypes.h>
29 
30 #ifdef __linux__
31 #include <linux/fs.h>
32 #endif
33 
34 #include "qemu/queue.h"
35 #include "qemu/main-loop.h"
36 
37 /* #define DEBUG_NBD */
38 
39 #ifdef DEBUG_NBD
40 #define TRACE(msg, ...) do { \
41     LOG(msg, ## __VA_ARGS__); \
42 } while(0)
43 #else
44 #define TRACE(msg, ...) \
45     do { } while (0)
46 #endif
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.txt
57  */
58 
59 #define NBD_REQUEST_SIZE        (4 + 4 + 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           0x3e889045565a9LL
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 
96 static inline ssize_t read_sync(QIOChannel *ioc, void *buffer, size_t size)
97 {
98     struct iovec iov = { .iov_base = buffer, .iov_len = size };
99     /* Sockets are kept in blocking mode in the negotiation phase.  After
100      * that, a non-readable socket simply means that another thread stole
101      * our request/reply.  Synchronization is done with recv_coroutine, so
102      * that this is coroutine-safe.
103      */
104     return nbd_wr_syncv(ioc, &iov, 1, 0, size, true);
105 }
106 
107 static inline ssize_t write_sync(QIOChannel *ioc, void *buffer, size_t size)
108 {
109     struct iovec iov = { .iov_base = buffer, .iov_len = size };
110 
111     return nbd_wr_syncv(ioc, &iov, 1, 0, size, false);
112 }
113 
114 struct NBDTLSHandshakeData {
115     GMainLoop *loop;
116     bool complete;
117     Error *error;
118 };
119 
120 
121 void nbd_tls_handshake(Object *src,
122                        Error *err,
123                        void *opaque);
124 
125 #endif
126