1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
3 */
4
5 #include <glob.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <unistd.h>
9 #include <signal.h>
10 #include <limits.h>
11 #include <fcntl.h>
12 #include <string.h>
13 #include <errno.h>
14 #include <poll.h>
15
16
17 #include <rte_log.h>
18
19 #include "guest_channel.h"
20 #include "channel_commands.h"
21
22 #define RTE_LOGTYPE_GUEST_CHANNEL RTE_LOGTYPE_USER1
23
24 /* Timeout for incoming message in milliseconds. */
25 #define TIMEOUT 10
26
27 static int global_fds[RTE_MAX_LCORE] = { [0 ... RTE_MAX_LCORE-1] = -1 };
28
29 int
guest_channel_host_check_exists(const char * path)30 guest_channel_host_check_exists(const char *path)
31 {
32 char glob_path[PATH_MAX];
33 glob_t g;
34 int ret;
35
36 /* we cannot know in advance which cores have VM channels, so glob */
37 snprintf(glob_path, PATH_MAX, "%s.*", path);
38
39 ret = glob(glob_path, GLOB_NOSORT, NULL, &g);
40 if (ret != 0) {
41 /* couldn't read anything */
42 ret = 0;
43 goto out;
44 }
45
46 /* do we have at least one match? */
47 ret = g.gl_pathc > 0;
48
49 out:
50 globfree(&g);
51 return ret;
52 }
53
54 int
guest_channel_host_connect(const char * path,unsigned int lcore_id)55 guest_channel_host_connect(const char *path, unsigned int lcore_id)
56 {
57 int flags, ret;
58 struct channel_packet pkt;
59 char fd_path[PATH_MAX];
60 int fd = -1;
61
62 if (lcore_id >= RTE_MAX_LCORE) {
63 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
64 lcore_id, RTE_MAX_LCORE-1);
65 return -1;
66 }
67 /* check if path is already open */
68 if (global_fds[lcore_id] != -1) {
69 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is already open with fd %d\n",
70 lcore_id, global_fds[lcore_id]);
71 return -1;
72 }
73
74 snprintf(fd_path, PATH_MAX, "%s.%u", path, lcore_id);
75 RTE_LOG(INFO, GUEST_CHANNEL, "Opening channel '%s' for lcore %u\n",
76 fd_path, lcore_id);
77 fd = open(fd_path, O_RDWR);
78 if (fd < 0) {
79 RTE_LOG(ERR, GUEST_CHANNEL, "Unable to to connect to '%s' with error "
80 "%s\n", fd_path, strerror(errno));
81 return -1;
82 }
83
84 flags = fcntl(fd, F_GETFL, 0);
85 if (flags < 0) {
86 RTE_LOG(ERR, GUEST_CHANNEL, "Failed on fcntl get flags for file %s\n",
87 fd_path);
88 goto error;
89 }
90
91 flags |= O_NONBLOCK;
92 if (fcntl(fd, F_SETFL, flags) < 0) {
93 RTE_LOG(ERR, GUEST_CHANNEL, "Failed on setting non-blocking mode for "
94 "file %s", fd_path);
95 goto error;
96 }
97 /* QEMU needs a delay after connection */
98 sleep(1);
99
100 /* Send a test packet, this command is ignored by the host, but a successful
101 * send indicates that the host endpoint is monitoring.
102 */
103 pkt.command = CPU_POWER_CONNECT;
104 global_fds[lcore_id] = fd;
105 ret = guest_channel_send_msg(&pkt, lcore_id);
106 if (ret != 0) {
107 RTE_LOG(ERR, GUEST_CHANNEL,
108 "Error on channel '%s' communications test: %s\n",
109 fd_path, ret > 0 ? strerror(ret) :
110 "channel not connected");
111 goto error;
112 }
113 RTE_LOG(INFO, GUEST_CHANNEL, "Channel '%s' is now connected\n", fd_path);
114 return 0;
115 error:
116 close(fd);
117 global_fds[lcore_id] = -1;
118 return -1;
119 }
120
121 int
guest_channel_send_msg(struct channel_packet * pkt,unsigned int lcore_id)122 guest_channel_send_msg(struct channel_packet *pkt, unsigned int lcore_id)
123 {
124 int ret, buffer_len = sizeof(*pkt);
125 void *buffer = pkt;
126
127 if (lcore_id >= RTE_MAX_LCORE) {
128 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
129 lcore_id, RTE_MAX_LCORE-1);
130 return -1;
131 }
132
133 if (global_fds[lcore_id] < 0) {
134 RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
135 return -1;
136 }
137 while (buffer_len > 0) {
138 ret = write(global_fds[lcore_id], buffer, buffer_len);
139 if (ret == buffer_len)
140 return 0;
141 if (ret == -1) {
142 if (errno == EINTR)
143 continue;
144 return errno;
145 }
146 buffer = (char *)buffer + ret;
147 buffer_len -= ret;
148 }
149 return 0;
150 }
151
rte_power_guest_channel_send_msg(struct channel_packet * pkt,unsigned int lcore_id)152 int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
153 unsigned int lcore_id)
154 {
155 return guest_channel_send_msg(pkt, lcore_id);
156 }
157
power_guest_channel_read_msg(void * pkt,size_t pkt_len,unsigned int lcore_id)158 int power_guest_channel_read_msg(void *pkt,
159 size_t pkt_len,
160 unsigned int lcore_id)
161 {
162 int ret;
163 struct pollfd fds;
164
165 if (pkt_len == 0 || pkt == NULL)
166 return -1;
167
168 fds.fd = global_fds[lcore_id];
169 fds.events = POLLIN;
170
171 ret = poll(&fds, 1, TIMEOUT);
172 if (ret == 0) {
173 RTE_LOG(DEBUG, GUEST_CHANNEL, "Timeout occurred during poll function.\n");
174 return -1;
175 } else if (ret < 0) {
176 RTE_LOG(ERR, GUEST_CHANNEL, "Error occurred during poll function: %s\n",
177 strerror(errno));
178 return -1;
179 }
180
181 if (lcore_id >= RTE_MAX_LCORE) {
182 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
183 lcore_id, RTE_MAX_LCORE-1);
184 return -1;
185 }
186
187 if (global_fds[lcore_id] < 0) {
188 RTE_LOG(ERR, GUEST_CHANNEL, "Channel is not connected\n");
189 return -1;
190 }
191
192 while (pkt_len > 0) {
193 ret = read(global_fds[lcore_id],
194 pkt, pkt_len);
195
196 if (ret < 0) {
197 if (errno == EINTR)
198 continue;
199 return -1;
200 }
201
202 if (ret == 0) {
203 RTE_LOG(ERR, GUEST_CHANNEL, "Expected more data, but connection has been closed.\n");
204 return -1;
205 }
206 pkt = (char *)pkt + ret;
207 pkt_len -= ret;
208 }
209
210 return 0;
211 }
212
rte_power_guest_channel_receive_msg(void * pkt,size_t pkt_len,unsigned int lcore_id)213 int rte_power_guest_channel_receive_msg(void *pkt,
214 size_t pkt_len,
215 unsigned int lcore_id)
216 {
217 return power_guest_channel_read_msg(pkt, pkt_len, lcore_id);
218 }
219
220 void
guest_channel_host_disconnect(unsigned int lcore_id)221 guest_channel_host_disconnect(unsigned int lcore_id)
222 {
223 if (lcore_id >= RTE_MAX_LCORE) {
224 RTE_LOG(ERR, GUEST_CHANNEL, "Channel(%u) is out of range 0...%d\n",
225 lcore_id, RTE_MAX_LCORE-1);
226 return;
227 }
228 if (global_fds[lcore_id] < 0)
229 return;
230 close(global_fds[lcore_id]);
231 global_fds[lcore_id] = -1;
232 }
233