aboutsummaryrefslogtreecommitdiffstats
path: root/lib/librte_power/guest_channel.c
blob: fa5de0f53a3038da5a3ae0bf57d6f781827a97e7 (plain)
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
/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <limits.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>


#include <rte_log.h>

#include "guest_channel.h"
#include "channel_commands.h"

#define RTE_LOGTYPE_GUEST_CHANNEL RTE_LOGTYPE_USER1

static int global_fds[RTE_MAX_LCORE];

int
guest_channel_host_connect(const char *path, unsigned lcore_id)
{
	int flags, ret;
	struct channel_packet pkt;
	char fd_path[PATH_MAX];
	int fd = -1;

	if (lcore_id >= RTE_MAX_LCORE) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
				lcore_id, RTE_MAX_LCORE-1);
		return -1;
	}
	/* check if path is already open */
	if (global_fds[lcore_id] != 0) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is already open with fd %d\n",
				lcore_id, global_fds[lcore_id]);
		return -1;
	}

	snprintf(fd_path, PATH_MAX, "%s.%u", path, lcore_id);
	RTE_LOG(INFO, GUEST_CHANNEL, "Opening channel '%s' for lcore %u\n",
			fd_path, lcore_id);
	fd = open(fd_path, O_RDWR);
	if (fd < 0) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Unable to to connect to '%s' with error "
				"%s\n", fd_path, strerror(errno));
		return -1;
	}

	flags = fcntl(fd, F_GETFL, 0);
	if (flags < 0) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Failed on fcntl get flags for file %s\n",
				fd_path);
		goto error;
	}

	flags |= O_NONBLOCK;
	if (fcntl(fd, F_SETFL, flags) < 0) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Failed on setting non-blocking mode for "
				"file %s", fd_path);
		goto error;
	}
	/* QEMU needs a delay after connection */
	sleep(1);

	/* Send a test packet, this command is ignored by the host, but a successful
	 * send indicates that the host endpoint is monitoring.
	 */
	pkt.command = CPU_POWER_CONNECT;
	global_fds[lcore_id] = fd;
	ret = guest_channel_send_msg(&pkt, lcore_id);
	if (ret != 0) {
		RTE_LOG(ERR, GUEST_CHANNEL,
				"Error on channel '%s' communications test: %s\n",
				fd_path, ret > 0 ? strerror(ret) :
				"channel not connected");
		goto error;
	}
	RTE_LOG(INFO, GUEST_CHANNEL, "Channel '%s' is now connected\n", fd_path);
	return 0;
error:
	close(fd);
	global_fds[lcore_id] = 0;
	return -1;
}

int
guest_channel_send_msg(struct channel_packet *pkt, unsigned lcore_id)
{
	int ret, buffer_len = sizeof(*pkt);
	void *buffer = pkt;

	if (lcore_id >= RTE_MAX_LCORE) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
				lcore_id, RTE_MAX_LCORE-1);
		return -1;
	}

	if (global_fds[lcore_id] == 0) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
		return -1;
	}
	while (buffer_len > 0) {
		ret = write(global_fds[lcore_id], buffer, buffer_len);
		if (ret == buffer_len)
			return 0;
		if (ret == -1) {
			if (errno == EINTR)
				continue;
			return errno;
		}
		buffer = (char *)buffer + ret;
		buffer_len -= ret;
	}
	return 0;
}

int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
			unsigned int lcore_id)
{
	return guest_channel_send_msg(pkt, lcore_id);
}


void
guest_channel_host_disconnect(unsigned lcore_id)
{
	if (lcore_id >= RTE_MAX_LCORE) {
		RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
				lcore_id, RTE_MAX_LCORE-1);
		return;
	}
	if (global_fds[lcore_id] == 0)
		return;
	close(global_fds[lcore_id]);
	global_fds[lcore_id] = 0;
}