xref: /openbmc/qemu/nbd/nbd-internal.h (revision b23197f9)
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/queue.h"
31 #include "qemu/main-loop.h"
32 
33 /* #define DEBUG_NBD */
34 
35 #ifdef DEBUG_NBD
36 #define TRACE(msg, ...) do { \
37     LOG(msg, ## __VA_ARGS__); \
38 } while(0)
39 #else
40 #define TRACE(msg, ...) \
41     do { } while (0)
42 #endif
43 
44 #define LOG(msg, ...) do { \
45     fprintf(stderr, "%s:%s():L%d: " msg "\n", \
46             __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
47 } while(0)
48 
49 /* This is all part of the "official" NBD API.
50  *
51  * The most up-to-date documentation is available at:
52  * https://github.com/yoe/nbd/blob/master/doc/proto.txt
53  */
54 
55 #define NBD_REQUEST_SIZE        (4 + 4 + 8 + 8 + 4)
56 #define NBD_REPLY_SIZE          (4 + 4 + 8)
57 #define NBD_REQUEST_MAGIC       0x25609513
58 #define NBD_REPLY_MAGIC         0x67446698
59 #define NBD_OPTS_MAGIC          0x49484156454F5054LL
60 #define NBD_CLIENT_MAGIC        0x0000420281861253LL
61 #define NBD_REP_MAGIC           0x3e889045565a9LL
62 
63 #define NBD_SET_SOCK            _IO(0xab, 0)
64 #define NBD_SET_BLKSIZE         _IO(0xab, 1)
65 #define NBD_SET_SIZE            _IO(0xab, 2)
66 #define NBD_DO_IT               _IO(0xab, 3)
67 #define NBD_CLEAR_SOCK          _IO(0xab, 4)
68 #define NBD_CLEAR_QUE           _IO(0xab, 5)
69 #define NBD_PRINT_DEBUG         _IO(0xab, 6)
70 #define NBD_SET_SIZE_BLOCKS     _IO(0xab, 7)
71 #define NBD_DISCONNECT          _IO(0xab, 8)
72 #define NBD_SET_TIMEOUT         _IO(0xab, 9)
73 #define NBD_SET_FLAGS           _IO(0xab, 10)
74 
75 #define NBD_OPT_EXPORT_NAME     (1)
76 #define NBD_OPT_ABORT           (2)
77 #define NBD_OPT_LIST            (3)
78 #define NBD_OPT_PEEK_EXPORT     (4)
79 #define NBD_OPT_STARTTLS        (5)
80 
81 /* NBD errors are based on errno numbers, so there is a 1:1 mapping,
82  * but only a limited set of errno values is specified in the protocol.
83  * Everything else is squashed to EINVAL.
84  */
85 #define NBD_SUCCESS    0
86 #define NBD_EPERM      1
87 #define NBD_EIO        5
88 #define NBD_ENOMEM     12
89 #define NBD_EINVAL     22
90 #define NBD_ENOSPC     28
91 
92 static inline ssize_t read_sync(QIOChannel *ioc, void *buffer, size_t size)
93 {
94     struct iovec iov = { .iov_base = buffer, .iov_len = size };
95     /* Sockets are kept in blocking mode in the negotiation phase.  After
96      * that, a non-readable socket simply means that another thread stole
97      * our request/reply.  Synchronization is done with recv_coroutine, so
98      * that this is coroutine-safe.
99      */
100     return nbd_wr_syncv(ioc, &iov, 1, 0, size, true);
101 }
102 
103 static inline ssize_t write_sync(QIOChannel *ioc, void *buffer, size_t size)
104 {
105     struct iovec iov = { .iov_base = buffer, .iov_len = size };
106 
107     return nbd_wr_syncv(ioc, &iov, 1, 0, size, false);
108 }
109 
110 struct NBDTLSHandshakeData {
111     GMainLoop *loop;
112     bool complete;
113     Error *error;
114 };
115 
116 
117 void nbd_tls_handshake(Object *src,
118                        Error *err,
119                        void *opaque);
120 
121 #endif
122