xref: /openbmc/qemu/nbd/common.c (revision 39164c13)
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 ssize_t nbd_wr_syncv(QIOChannel *ioc,
24                      struct iovec *iov,
25                      size_t niov,
26                      size_t length,
27                      bool do_read)
28 {
29     ssize_t done = 0;
30     Error *local_err = NULL;
31     struct iovec *local_iov = g_new(struct iovec, niov);
32     struct iovec *local_iov_head = local_iov;
33     unsigned int nlocal_iov = niov;
34 
35     nlocal_iov = iov_copy(local_iov, nlocal_iov, iov, niov, 0, length);
36 
37     while (nlocal_iov > 0) {
38         ssize_t len;
39         if (do_read) {
40             len = qio_channel_readv(ioc, local_iov, nlocal_iov, &local_err);
41         } else {
42             len = qio_channel_writev(ioc, local_iov, nlocal_iov, &local_err);
43         }
44         if (len == QIO_CHANNEL_ERR_BLOCK) {
45             if (qemu_in_coroutine()) {
46                 qio_channel_yield(ioc, do_read ? G_IO_IN : G_IO_OUT);
47             } else {
48                 return -EAGAIN;
49             }
50             continue;
51         }
52         if (len < 0) {
53             TRACE("I/O error: %s", error_get_pretty(local_err));
54             error_free(local_err);
55             /* XXX handle Error objects */
56             done = -EIO;
57             goto cleanup;
58         }
59 
60         if (do_read && len == 0) {
61             break;
62         }
63 
64         iov_discard_front(&local_iov, &nlocal_iov, len);
65         done += len;
66     }
67 
68  cleanup:
69     g_free(local_iov_head);
70     return done;
71 }
72 
73 
74 void nbd_tls_handshake(QIOTask *task,
75                        void *opaque)
76 {
77     struct NBDTLSHandshakeData *data = opaque;
78 
79     if (qio_task_propagate_error(task, &data->error)) {
80         TRACE("TLS failed %s", error_get_pretty(data->error));
81     }
82     data->complete = true;
83     g_main_loop_quit(data->loop);
84 }
85