1 /*
2  * This work is licensed under the terms of the GNU GPL, version 2 or
3  * (at your option) any later version.  See the COPYING file in the
4  * top-level directory.
5  */
6 
7 #include "qemu/osdep.h"
8 
9 #include <sys/ioctl.h>
10 
11 #include "qemu/iov.h"
12 #include "qemu/bswap.h"
13 #include "qemu/sockets.h"
14 #include "libvhost-user-glib.h"
15 #include "standard-headers/linux/input.h"
16 #include "standard-headers/linux/virtio_input.h"
17 #include "qapi/error.h"
18 
19 enum {
20     VHOST_USER_INPUT_MAX_QUEUES = 2,
21 };
22 
23 typedef struct virtio_input_event virtio_input_event;
24 typedef struct virtio_input_config virtio_input_config;
25 
26 typedef struct VuInput {
27     VugDev dev;
28     GSource *evsrc;
29     int evdevfd;
30     GArray *config;
31     virtio_input_config *sel_config;
32     struct {
33         virtio_input_event event;
34         VuVirtqElement *elem;
35     } *queue;
36     uint32_t qindex, qsize;
37 } VuInput;
38 
39 static void vi_input_send(VuInput *vi, struct virtio_input_event *event)
40 {
41     VuDev *dev = &vi->dev.parent;
42     VuVirtq *vq = vu_get_queue(dev, 0);
43     VuVirtqElement *elem;
44     int i, len;
45 
46     /* queue up events ... */
47     if (vi->qindex == vi->qsize) {
48         vi->qsize++;
49         vi->queue = g_realloc_n(vi->queue, vi->qsize, sizeof(vi->queue[0]));
50     }
51     vi->queue[vi->qindex++].event = *event;
52 
53     /* ... until we see a report sync ... */
54     if (event->type != cpu_to_le16(EV_SYN) ||
55         event->code != cpu_to_le16(SYN_REPORT)) {
56         return;
57     }
58 
59     /* ... then check available space ... */
60     for (i = 0; i < vi->qindex; i++) {
61         elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
62         if (!elem) {
63             while (--i >= 0) {
64                 vu_queue_unpop(dev, vq, vi->queue[i].elem, 0);
65             }
66             vi->qindex = 0;
67             g_warning("virtio-input queue full");
68             return;
69         }
70         vi->queue[i].elem = elem;
71     }
72 
73     /* ... and finally pass them to the guest */
74     for (i = 0; i < vi->qindex; i++) {
75         elem = vi->queue[i].elem;
76         len = iov_from_buf(elem->in_sg, elem->in_num,
77                            0, &vi->queue[i].event, sizeof(virtio_input_event));
78         vu_queue_push(dev, vq, elem, len);
79         free(elem);
80     }
81 
82     vu_queue_notify(&vi->dev.parent, vq);
83     vi->qindex = 0;
84 }
85 
86 static void
87 vi_evdev_watch(VuDev *dev, int condition, void *data)
88 {
89     VuInput *vi = data;
90     int fd = vi->evdevfd;
91 
92     g_debug("Got evdev condition %x", condition);
93 
94     struct virtio_input_event virtio;
95     struct input_event evdev;
96     int rc;
97 
98     for (;;) {
99         rc = read(fd, &evdev, sizeof(evdev));
100         if (rc != sizeof(evdev)) {
101             break;
102         }
103 
104         g_debug("input %d %d %d", evdev.type, evdev.code, evdev.value);
105 
106         virtio.type  = cpu_to_le16(evdev.type);
107         virtio.code  = cpu_to_le16(evdev.code);
108         virtio.value = cpu_to_le32(evdev.value);
109         vi_input_send(vi, &virtio);
110     }
111 }
112 
113 
114 static void vi_handle_status(VuInput *vi, virtio_input_event *event)
115 {
116     struct input_event evdev;
117     struct timeval tval;
118     int rc;
119 
120     if (gettimeofday(&tval, NULL)) {
121         perror("vi_handle_status: gettimeofday");
122         return;
123     }
124 
125     evdev.input_event_sec = tval.tv_sec;
126     evdev.input_event_usec = tval.tv_usec;
127     evdev.type = le16_to_cpu(event->type);
128     evdev.code = le16_to_cpu(event->code);
129     evdev.value = le32_to_cpu(event->value);
130 
131     rc = write(vi->evdevfd, &evdev, sizeof(evdev));
132     if (rc == -1) {
133         perror("vi_host_handle_status: write");
134     }
135 }
136 
137 static void vi_handle_sts(VuDev *dev, int qidx)
138 {
139     VuInput *vi = container_of(dev, VuInput, dev.parent);
140     VuVirtq *vq = vu_get_queue(dev, qidx);
141     virtio_input_event event;
142     VuVirtqElement *elem;
143     int len;
144 
145     g_debug("%s", G_STRFUNC);
146 
147     for (;;) {
148         elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
149         if (!elem) {
150             break;
151         }
152 
153         memset(&event, 0, sizeof(event));
154         len = iov_to_buf(elem->out_sg, elem->out_num,
155                          0, &event, sizeof(event));
156         vi_handle_status(vi, &event);
157         vu_queue_push(dev, vq, elem, len);
158         free(elem);
159     }
160 
161     vu_queue_notify(&vi->dev.parent, vq);
162 }
163 
164 static void
165 vi_panic(VuDev *dev, const char *msg)
166 {
167     g_critical("%s\n", msg);
168     exit(EXIT_FAILURE);
169 }
170 
171 static void
172 vi_queue_set_started(VuDev *dev, int qidx, bool started)
173 {
174     VuInput *vi = container_of(dev, VuInput, dev.parent);
175     VuVirtq *vq = vu_get_queue(dev, qidx);
176 
177     g_debug("queue started %d:%d", qidx, started);
178 
179     if (qidx == 1) {
180         vu_set_queue_handler(dev, vq, started ? vi_handle_sts : NULL);
181     }
182 
183     started = vu_queue_started(dev, vu_get_queue(dev, 0)) &&
184         vu_queue_started(dev, vu_get_queue(dev, 1));
185 
186     if (started && !vi->evsrc) {
187         vi->evsrc = vug_source_new(&vi->dev, vi->evdevfd,
188                                    G_IO_IN, vi_evdev_watch, vi);
189     }
190 
191     if (!started && vi->evsrc) {
192         vug_source_destroy(vi->evsrc);
193         vi->evsrc = NULL;
194     }
195 }
196 
197 static virtio_input_config *
198 vi_find_config(VuInput *vi, uint8_t select, uint8_t subsel)
199 {
200     virtio_input_config *cfg;
201     int i;
202 
203     for (i = 0; i < vi->config->len; i++) {
204         cfg = &g_array_index(vi->config, virtio_input_config, i);
205         if (select == cfg->select && subsel == cfg->subsel) {
206             return cfg;
207         }
208     }
209 
210     return NULL;
211 }
212 
213 static int vi_get_config(VuDev *dev, uint8_t *config, uint32_t len)
214 {
215     VuInput *vi = container_of(dev, VuInput, dev.parent);
216 
217     if (len > sizeof(*vi->sel_config)) {
218         return -1;
219     }
220 
221     if (vi->sel_config) {
222         memcpy(config, vi->sel_config, len);
223     } else {
224         memset(config, 0, len);
225     }
226 
227     return 0;
228 }
229 
230 static int vi_set_config(VuDev *dev, const uint8_t *data,
231                          uint32_t offset, uint32_t size,
232                          uint32_t flags)
233 {
234     VuInput *vi = container_of(dev, VuInput, dev.parent);
235     virtio_input_config *config = (virtio_input_config *)data;
236 
237     vi->sel_config = vi_find_config(vi, config->select, config->subsel);
238 
239     return 0;
240 }
241 
242 static const VuDevIface vuiface = {
243     .queue_set_started = vi_queue_set_started,
244     .get_config = vi_get_config,
245     .set_config = vi_set_config,
246 };
247 
248 static void
249 vi_bits_config(VuInput *vi, int type, int count)
250 {
251     virtio_input_config bits;
252     int rc, i, size = 0;
253 
254     memset(&bits, 0, sizeof(bits));
255     rc = ioctl(vi->evdevfd, EVIOCGBIT(type, count / 8), bits.u.bitmap);
256     if (rc < 0) {
257         return;
258     }
259 
260     for (i = 0; i < count / 8; i++) {
261         if (bits.u.bitmap[i]) {
262             size = i + 1;
263         }
264     }
265     if (size == 0) {
266         return;
267     }
268 
269     bits.select = VIRTIO_INPUT_CFG_EV_BITS;
270     bits.subsel = type;
271     bits.size   = size;
272     g_array_append_val(vi->config, bits);
273 }
274 
275 static char *opt_evdev;
276 static int opt_fdnum = -1;
277 static char *opt_socket_path;
278 static gboolean opt_nograb;
279 static gboolean opt_print_caps;
280 
281 static GOptionEntry entries[] = {
282     { "print-capabilities", 'c', 0, G_OPTION_ARG_NONE, &opt_print_caps,
283       "Print capabilities", NULL },
284     { "no-grab", 'n', 0, G_OPTION_ARG_NONE, &opt_nograb,
285       "Don't grab device", NULL },
286     { "fd", 'f', 0, G_OPTION_ARG_INT, &opt_fdnum,
287       "Use inherited fd socket", "FDNUM" },
288     { "socket-path", 's', 0, G_OPTION_ARG_FILENAME, &opt_socket_path,
289       "Use UNIX socket path", "PATH" },
290     { "evdev-path", 'p', 0, G_OPTION_ARG_FILENAME, &opt_evdev,
291       "evdev input device path", "PATH" },
292     { NULL, }
293 };
294 
295 int
296 main(int argc, char *argv[])
297 {
298     GMainLoop *loop = NULL;
299     VuInput vi = { 0, };
300     int rc, ver, fd;
301     virtio_input_config id;
302     struct input_id ids;
303     GError *error = NULL;
304     GOptionContext *context;
305 
306     context = g_option_context_new(NULL);
307     g_option_context_add_main_entries(context, entries, NULL);
308     if (!g_option_context_parse(context, &argc, &argv, &error)) {
309         g_printerr("Option parsing failed: %s\n", error->message);
310         exit(EXIT_FAILURE);
311     }
312     if (opt_print_caps) {
313         g_print("{\n");
314         g_print("  \"type\": \"input\",\n");
315         g_print("  \"features\": [\n");
316         g_print("    \"evdev-path\",\n");
317         g_print("    \"no-grab\"\n");
318         g_print("  ]\n");
319         g_print("}\n");
320         exit(EXIT_SUCCESS);
321     }
322     if (!opt_evdev) {
323         g_printerr("Please specify an evdev path\n");
324         exit(EXIT_FAILURE);
325     }
326     if ((!!opt_socket_path + (opt_fdnum != -1)) != 1) {
327         g_printerr("Please specify either --fd or --socket-path\n");
328         exit(EXIT_FAILURE);
329     }
330 
331     vi.evdevfd = open(opt_evdev, O_RDWR);
332     if (vi.evdevfd < 0) {
333         g_printerr("Failed to open evdev: %s\n", g_strerror(errno));
334         exit(EXIT_FAILURE);
335     }
336 
337     rc = ioctl(vi.evdevfd, EVIOCGVERSION, &ver);
338     if (rc < 0) {
339         g_printerr("%s: is not an evdev device\n", argv[1]);
340         exit(EXIT_FAILURE);
341     }
342 
343     if (!opt_nograb) {
344         rc = ioctl(vi.evdevfd, EVIOCGRAB, 1);
345         if (rc < 0) {
346             g_printerr("Failed to grab device\n");
347             exit(EXIT_FAILURE);
348         }
349     }
350 
351     vi.config = g_array_new(false, false, sizeof(virtio_input_config));
352     memset(&id, 0, sizeof(id));
353     if (ioctl(vi.evdevfd, EVIOCGNAME(sizeof(id.u.string) - 1),
354               id.u.string) < 0) {
355         g_printerr("Failed to get evdev name: %s\n", g_strerror(errno));
356         exit(EXIT_FAILURE);
357     }
358     id.select = VIRTIO_INPUT_CFG_ID_NAME;
359     id.size = strlen(id.u.string);
360     g_array_append_val(vi.config, id);
361 
362     if (ioctl(vi.evdevfd, EVIOCGID, &ids) == 0) {
363         memset(&id, 0, sizeof(id));
364         id.select = VIRTIO_INPUT_CFG_ID_DEVIDS;
365         id.size = sizeof(struct virtio_input_devids);
366         id.u.ids.bustype = cpu_to_le16(ids.bustype);
367         id.u.ids.vendor  = cpu_to_le16(ids.vendor);
368         id.u.ids.product = cpu_to_le16(ids.product);
369         id.u.ids.version = cpu_to_le16(ids.version);
370         g_array_append_val(vi.config, id);
371     }
372 
373     vi_bits_config(&vi, EV_KEY, KEY_CNT);
374     vi_bits_config(&vi, EV_REL, REL_CNT);
375     vi_bits_config(&vi, EV_ABS, ABS_CNT);
376     vi_bits_config(&vi, EV_MSC, MSC_CNT);
377     vi_bits_config(&vi, EV_SW,  SW_CNT);
378     g_debug("config length: %u", vi.config->len);
379 
380     if (opt_socket_path) {
381         int lsock = unix_listen(opt_socket_path, &error_fatal);
382         if (lsock < 0) {
383             g_printerr("Failed to listen on %s.\n", opt_socket_path);
384             exit(EXIT_FAILURE);
385         }
386         fd = accept(lsock, NULL, NULL);
387         close(lsock);
388     } else {
389         fd = opt_fdnum;
390     }
391     if (fd == -1) {
392         g_printerr("Invalid vhost-user socket.\n");
393         exit(EXIT_FAILURE);
394     }
395 
396     if (!vug_init(&vi.dev, VHOST_USER_INPUT_MAX_QUEUES, fd, vi_panic,
397                   &vuiface)) {
398         g_printerr("Failed to initialize libvhost-user-glib.\n");
399         exit(EXIT_FAILURE);
400     }
401 
402     loop = g_main_loop_new(NULL, FALSE);
403     g_main_loop_run(loop);
404     g_main_loop_unref(loop);
405 
406     vug_deinit(&vi.dev);
407 
408     vug_source_destroy(vi.evsrc);
409     g_array_free(vi.config, TRUE);
410     g_free(vi.queue);
411     return 0;
412 }
413