xref: /qemu/nbd/common.c (revision 7271a819)
1 /*
2  *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>
3  *
4  *  Network Block Device Common Code
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; under version 2 of the License.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include "qemu/osdep.h"
20 #include "qapi/error.h"
21 #include "nbd-internal.h"
22 
23 /* Discard length bytes from channel.  Return -errno on failure and 0 on
24  * success */
25 int nbd_drop(QIOChannel *ioc, size_t size, Error **errp)
26 {
27     ssize_t ret = 0;
28     char small[1024];
29     char *buffer;
30 
31     buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size));
32     while (size > 0) {
33         ssize_t count = MIN(65536, size);
34         ret = nbd_read(ioc, buffer, MIN(65536, size), errp);
35 
36         if (ret < 0) {
37             goto cleanup;
38         }
39         size -= count;
40     }
41 
42  cleanup:
43     if (buffer != small) {
44         g_free(buffer);
45     }
46     return ret;
47 }
48 
49 
50 void nbd_tls_handshake(QIOTask *task,
51                        void *opaque)
52 {
53     struct NBDTLSHandshakeData *data = opaque;
54 
55     qio_task_propagate_error(task, &data->error);
56     data->complete = true;
57     g_main_loop_quit(data->loop);
58 }
59 
60 
61 const char *nbd_opt_lookup(uint32_t opt)
62 {
63     switch (opt) {
64     case NBD_OPT_EXPORT_NAME:
65         return "export name";
66     case NBD_OPT_ABORT:
67         return "abort";
68     case NBD_OPT_LIST:
69         return "list";
70     case NBD_OPT_STARTTLS:
71         return "starttls";
72     case NBD_OPT_INFO:
73         return "info";
74     case NBD_OPT_GO:
75         return "go";
76     case NBD_OPT_STRUCTURED_REPLY:
77         return "structured reply";
78     default:
79         return "<unknown>";
80     }
81 }
82 
83 
84 const char *nbd_rep_lookup(uint32_t rep)
85 {
86     switch (rep) {
87     case NBD_REP_ACK:
88         return "ack";
89     case NBD_REP_SERVER:
90         return "server";
91     case NBD_REP_INFO:
92         return "info";
93     case NBD_REP_ERR_UNSUP:
94         return "unsupported";
95     case NBD_REP_ERR_POLICY:
96         return "denied by policy";
97     case NBD_REP_ERR_INVALID:
98         return "invalid";
99     case NBD_REP_ERR_PLATFORM:
100         return "platform lacks support";
101     case NBD_REP_ERR_TLS_REQD:
102         return "TLS required";
103     case NBD_REP_ERR_UNKNOWN:
104         return "export unknown";
105     case NBD_REP_ERR_SHUTDOWN:
106         return "server shutting down";
107     case NBD_REP_ERR_BLOCK_SIZE_REQD:
108         return "block size required";
109     default:
110         return "<unknown>";
111     }
112 }
113 
114 
115 const char *nbd_info_lookup(uint16_t info)
116 {
117     switch (info) {
118     case NBD_INFO_EXPORT:
119         return "export";
120     case NBD_INFO_NAME:
121         return "name";
122     case NBD_INFO_DESCRIPTION:
123         return "description";
124     case NBD_INFO_BLOCK_SIZE:
125         return "block size";
126     default:
127         return "<unknown>";
128     }
129 }
130 
131 
132 const char *nbd_cmd_lookup(uint16_t cmd)
133 {
134     switch (cmd) {
135     case NBD_CMD_READ:
136         return "read";
137     case NBD_CMD_WRITE:
138         return "write";
139     case NBD_CMD_DISC:
140         return "disconnect";
141     case NBD_CMD_FLUSH:
142         return "flush";
143     case NBD_CMD_TRIM:
144         return "trim";
145     case NBD_CMD_WRITE_ZEROES:
146         return "write zeroes";
147     default:
148         return "<unknown>";
149     }
150 }
151