1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
/*
* QEMU Block driver for NBD
*
* Copyright (C) 2008 Bull S.A.S.
* Author: Laurent Vivier <Laurent.Vivier@bull.net>
*
* Some parts:
* Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu-common.h"
#include "nbd.h"
#include <sys/types.h>
#include <unistd.h>
typedef struct BDRVNBDState {
int sock;
off_t size;
size_t blocksize;
} BDRVNBDState;
static int nbd_open(BlockDriverState *bs, const char* filename, int flags)
{
BDRVNBDState *s = bs->opaque;
const char *host;
const char *unixpath;
int sock;
off_t size;
size_t blocksize;
int ret;
if ((flags & BDRV_O_CREAT))
return -EINVAL;
if (!strstart(filename, "nbd:", &host))
return -EINVAL;
if (strstart(host, "unix:", &unixpath)) {
if (unixpath[0] != '/')
return -EINVAL;
sock = unix_socket_outgoing(unixpath);
} else {
uint16_t port;
char *p, *r;
char hostname[128];
pstrcpy(hostname, 128, host);
p = strchr(hostname, ':');
if (p == NULL)
return -EINVAL;
*p = '\0';
p++;
port = strtol(p, &r, 0);
if (r == p)
return -EINVAL;
sock = tcp_socket_outgoing(hostname, port);
}
if (sock == -1)
return -errno;
ret = nbd_receive_negotiate(sock, &size, &blocksize);
if (ret == -1)
return -errno;
s->sock = sock;
s->size = size;
s->blocksize = blocksize;
return 0;
}
static int nbd_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
struct nbd_reply reply;
request.type = NBD_CMD_READ;
request.handle = (uint64_t)(intptr_t)bs;
request.from = sector_num * 512;;
request.len = nb_sectors * 512;
if (nbd_send_request(s->sock, &request) == -1)
return -errno;
if (nbd_receive_reply(s->sock, &reply) == -1)
return -errno;
if (reply.error !=0)
return -reply.error;
if (reply.handle != request.handle)
return -EIO;
if (nbd_wr_sync(s->sock, buf, request.len, 1) != request.len)
return -EIO;
return 0;
}
static int nbd_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
struct nbd_reply reply;
request.type = NBD_CMD_WRITE;
request.handle = (uint64_t)(intptr_t)bs;
request.from = sector_num * 512;;
request.len = nb_sectors * 512;
if (nbd_send_request(s->sock, &request) == -1)
return -errno;
if (nbd_wr_sync(s->sock, (uint8_t*)buf, request.len, 0) != request.len)
return -EIO;
if (nbd_receive_reply(s->sock, &reply) == -1)
return -errno;
if (reply.error !=0)
return -reply.error;
if (reply.handle != request.handle)
return -EIO;
return 0;
}
static void nbd_close(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
request.type = NBD_CMD_DISC;
request.handle = (uint64_t)(intptr_t)bs;
request.from = 0;
request.len = 0;
nbd_send_request(s->sock, &request);
close(s->sock);
}
static int64_t nbd_getlength(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
return s->size;
}
BlockDriver bdrv_nbd = {
"nbd",
sizeof(BDRVNBDState),
NULL, /* no probe for protocols */
nbd_open,
nbd_read,
nbd_write,
nbd_close,
.bdrv_getlength = nbd_getlength,
.protocol_name = "nbd",
};
|
