balloon: Don't balloon roms
[qemu.git] / nbd / common.c
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 /* XXX figure out if we can create a variant on
47 * qio_channel_yield() that works with AIO contexts
48 * and consider using that in this branch */
49 qemu_coroutine_yield();
50 } else if (done) {
51 /* XXX this is needed by nbd_reply_ready. */
52 qio_channel_wait(ioc,
53 do_read ? G_IO_IN : G_IO_OUT);
54 } else {
55 return -EAGAIN;
56 }
57 continue;
58 }
59 if (len < 0) {
60 TRACE("I/O error: %s", error_get_pretty(local_err));
61 error_free(local_err);
62 /* XXX handle Error objects */
63 done = -EIO;
64 goto cleanup;
65 }
66
67 if (do_read && len == 0) {
68 break;
69 }
70
71 iov_discard_front(&local_iov, &nlocal_iov, len);
72 done += len;
73 }
74
75 cleanup:
76 g_free(local_iov_head);
77 return done;
78 }
79
80
81 void nbd_tls_handshake(Object *src,
82 Error *err,
83 void *opaque)
84 {
85 struct NBDTLSHandshakeData *data = opaque;
86
87 if (err) {
88 TRACE("TLS failed %s", error_get_pretty(err));
89 data->error = error_copy(err);
90 }
91 data->complete = true;
92 g_main_loop_quit(data->loop);
93 }