1 | /* |
2 | * A bus for connecting virtio serial and console ports |
3 | * |
4 | * Copyright (C) 2009, 2010 Red Hat, Inc. |
5 | * |
6 | * Author(s): |
7 | * Amit Shah <amit.shah@redhat.com> |
8 | * |
9 | * Some earlier parts are: |
10 | * Copyright IBM, Corp. 2008 |
11 | * authored by |
12 | * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> |
13 | * |
14 | * This work is licensed under the terms of the GNU GPL, version 2. See |
15 | * the COPYING file in the top-level directory. |
16 | * |
17 | * Contributions after 2012-01-13 are licensed under the terms of the |
18 | * GNU GPL, version 2 or (at your option) any later version. |
19 | */ |
20 | |
21 | #include "qemu/osdep.h" |
22 | #include "qapi/error.h" |
23 | #include "qemu/iov.h" |
24 | #include "qemu/main-loop.h" |
25 | #include "qemu/module.h" |
26 | #include "migration/qemu-file-types.h" |
27 | #include "monitor/monitor.h" |
28 | #include "qemu/error-report.h" |
29 | #include "qemu/queue.h" |
30 | #include "hw/qdev-properties.h" |
31 | #include "hw/sysbus.h" |
32 | #include "trace.h" |
33 | #include "hw/virtio/virtio-serial.h" |
34 | #include "hw/virtio/virtio-access.h" |
35 | |
36 | static struct VirtIOSerialDevices { |
37 | QLIST_HEAD(, VirtIOSerial) devices; |
38 | } vserdevices; |
39 | |
40 | static VirtIOSerialPort *find_port_by_id(VirtIOSerial *vser, uint32_t id) |
41 | { |
42 | VirtIOSerialPort *port; |
43 | |
44 | if (id == VIRTIO_CONSOLE_BAD_ID) { |
45 | return NULL; |
46 | } |
47 | |
48 | QTAILQ_FOREACH(port, &vser->ports, next) { |
49 | if (port->id == id) |
50 | return port; |
51 | } |
52 | return NULL; |
53 | } |
54 | |
55 | static VirtIOSerialPort *find_port_by_vq(VirtIOSerial *vser, VirtQueue *vq) |
56 | { |
57 | VirtIOSerialPort *port; |
58 | |
59 | QTAILQ_FOREACH(port, &vser->ports, next) { |
60 | if (port->ivq == vq || port->ovq == vq) |
61 | return port; |
62 | } |
63 | return NULL; |
64 | } |
65 | |
66 | static VirtIOSerialPort *find_port_by_name(char *name) |
67 | { |
68 | VirtIOSerial *vser; |
69 | |
70 | QLIST_FOREACH(vser, &vserdevices.devices, next) { |
71 | VirtIOSerialPort *port; |
72 | |
73 | QTAILQ_FOREACH(port, &vser->ports, next) { |
74 | if (port->name && !strcmp(port->name, name)) { |
75 | return port; |
76 | } |
77 | } |
78 | } |
79 | return NULL; |
80 | } |
81 | |
82 | static VirtIOSerialPort *find_first_connected_console(VirtIOSerial *vser) |
83 | { |
84 | VirtIOSerialPort *port; |
85 | |
86 | QTAILQ_FOREACH(port, &vser->ports, next) { |
87 | VirtIOSerialPortClass const *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
88 | if (vsc->is_console && port->host_connected) { |
89 | return port; |
90 | } |
91 | } |
92 | return NULL; |
93 | } |
94 | |
95 | static bool use_multiport(VirtIOSerial *vser) |
96 | { |
97 | VirtIODevice *vdev = VIRTIO_DEVICE(vser); |
98 | return virtio_vdev_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT); |
99 | } |
100 | |
101 | static size_t write_to_port(VirtIOSerialPort *port, |
102 | const uint8_t *buf, size_t size) |
103 | { |
104 | VirtQueueElement *elem; |
105 | VirtQueue *vq; |
106 | size_t offset; |
107 | |
108 | vq = port->ivq; |
109 | if (!virtio_queue_ready(vq)) { |
110 | return 0; |
111 | } |
112 | |
113 | offset = 0; |
114 | while (offset < size) { |
115 | size_t len; |
116 | |
117 | elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); |
118 | if (!elem) { |
119 | break; |
120 | } |
121 | |
122 | len = iov_from_buf(elem->in_sg, elem->in_num, 0, |
123 | buf + offset, size - offset); |
124 | offset += len; |
125 | |
126 | virtqueue_push(vq, elem, len); |
127 | g_free(elem); |
128 | } |
129 | |
130 | virtio_notify(VIRTIO_DEVICE(port->vser), vq); |
131 | return offset; |
132 | } |
133 | |
134 | static void discard_vq_data(VirtQueue *vq, VirtIODevice *vdev) |
135 | { |
136 | VirtQueueElement *elem; |
137 | |
138 | if (!virtio_queue_ready(vq)) { |
139 | return; |
140 | } |
141 | for (;;) { |
142 | elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); |
143 | if (!elem) { |
144 | break; |
145 | } |
146 | virtqueue_push(vq, elem, 0); |
147 | g_free(elem); |
148 | } |
149 | virtio_notify(vdev, vq); |
150 | } |
151 | |
152 | static void discard_throttle_data(VirtIOSerialPort *port) |
153 | { |
154 | if (port->elem) { |
155 | virtqueue_detach_element(port->ovq, port->elem, 0); |
156 | g_free(port->elem); |
157 | port->elem = NULL; |
158 | } |
159 | } |
160 | |
161 | static void do_flush_queued_data(VirtIOSerialPort *port, VirtQueue *vq, |
162 | VirtIODevice *vdev) |
163 | { |
164 | VirtIOSerialPortClass *vsc; |
165 | |
166 | assert(port); |
167 | assert(virtio_queue_ready(vq)); |
168 | |
169 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
170 | |
171 | while (!port->throttled) { |
172 | unsigned int i; |
173 | |
174 | /* Pop an elem only if we haven't left off a previous one mid-way */ |
175 | if (!port->elem) { |
176 | port->elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); |
177 | if (!port->elem) { |
178 | break; |
179 | } |
180 | port->iov_idx = 0; |
181 | port->iov_offset = 0; |
182 | } |
183 | |
184 | for (i = port->iov_idx; i < port->elem->out_num; i++) { |
185 | size_t buf_size; |
186 | ssize_t ret; |
187 | |
188 | buf_size = port->elem->out_sg[i].iov_len - port->iov_offset; |
189 | ret = vsc->have_data(port, |
190 | port->elem->out_sg[i].iov_base |
191 | + port->iov_offset, |
192 | buf_size); |
193 | if (!port->elem) { /* bail if we got disconnected */ |
194 | return; |
195 | } |
196 | if (port->throttled) { |
197 | port->iov_idx = i; |
198 | if (ret > 0) { |
199 | port->iov_offset += ret; |
200 | } |
201 | break; |
202 | } |
203 | port->iov_offset = 0; |
204 | } |
205 | if (port->throttled) { |
206 | break; |
207 | } |
208 | virtqueue_push(vq, port->elem, 0); |
209 | g_free(port->elem); |
210 | port->elem = NULL; |
211 | } |
212 | virtio_notify(vdev, vq); |
213 | } |
214 | |
215 | static void flush_queued_data(VirtIOSerialPort *port) |
216 | { |
217 | assert(port); |
218 | |
219 | if (!virtio_queue_ready(port->ovq)) { |
220 | return; |
221 | } |
222 | do_flush_queued_data(port, port->ovq, VIRTIO_DEVICE(port->vser)); |
223 | } |
224 | |
225 | static size_t send_control_msg(VirtIOSerial *vser, void *buf, size_t len) |
226 | { |
227 | VirtQueueElement *elem; |
228 | VirtQueue *vq; |
229 | |
230 | vq = vser->c_ivq; |
231 | if (!virtio_queue_ready(vq)) { |
232 | return 0; |
233 | } |
234 | |
235 | elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); |
236 | if (!elem) { |
237 | return 0; |
238 | } |
239 | |
240 | /* TODO: detect a buffer that's too short, set NEEDS_RESET */ |
241 | iov_from_buf(elem->in_sg, elem->in_num, 0, buf, len); |
242 | |
243 | virtqueue_push(vq, elem, len); |
244 | virtio_notify(VIRTIO_DEVICE(vser), vq); |
245 | g_free(elem); |
246 | |
247 | return len; |
248 | } |
249 | |
250 | static size_t send_control_event(VirtIOSerial *vser, uint32_t port_id, |
251 | uint16_t event, uint16_t value) |
252 | { |
253 | VirtIODevice *vdev = VIRTIO_DEVICE(vser); |
254 | struct virtio_console_control cpkt; |
255 | |
256 | virtio_stl_p(vdev, &cpkt.id, port_id); |
257 | virtio_stw_p(vdev, &cpkt.event, event); |
258 | virtio_stw_p(vdev, &cpkt.value, value); |
259 | |
260 | trace_virtio_serial_send_control_event(port_id, event, value); |
261 | return send_control_msg(vser, &cpkt, sizeof(cpkt)); |
262 | } |
263 | |
264 | /* Functions for use inside qemu to open and read from/write to ports */ |
265 | int virtio_serial_open(VirtIOSerialPort *port) |
266 | { |
267 | /* Don't allow opening an already-open port */ |
268 | if (port->host_connected) { |
269 | return 0; |
270 | } |
271 | /* Send port open notification to the guest */ |
272 | port->host_connected = true; |
273 | send_control_event(port->vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 1); |
274 | |
275 | return 0; |
276 | } |
277 | |
278 | int virtio_serial_close(VirtIOSerialPort *port) |
279 | { |
280 | port->host_connected = false; |
281 | /* |
282 | * If there's any data the guest sent which the app didn't |
283 | * consume, reset the throttling flag and discard the data. |
284 | */ |
285 | port->throttled = false; |
286 | discard_throttle_data(port); |
287 | discard_vq_data(port->ovq, VIRTIO_DEVICE(port->vser)); |
288 | |
289 | send_control_event(port->vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 0); |
290 | |
291 | return 0; |
292 | } |
293 | |
294 | /* Individual ports/apps call this function to write to the guest. */ |
295 | ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf, |
296 | size_t size) |
297 | { |
298 | if (!port || !port->host_connected || !port->guest_connected) { |
299 | return 0; |
300 | } |
301 | return write_to_port(port, buf, size); |
302 | } |
303 | |
304 | /* |
305 | * Readiness of the guest to accept data on a port. |
306 | * Returns max. data the guest can receive |
307 | */ |
308 | size_t virtio_serial_guest_ready(VirtIOSerialPort *port) |
309 | { |
310 | VirtIODevice *vdev = VIRTIO_DEVICE(port->vser); |
311 | VirtQueue *vq = port->ivq; |
312 | unsigned int bytes; |
313 | |
314 | if (!virtio_queue_ready(vq) || |
315 | !(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) || |
316 | virtio_queue_empty(vq)) { |
317 | return 0; |
318 | } |
319 | if (use_multiport(port->vser) && !port->guest_connected) { |
320 | return 0; |
321 | } |
322 | virtqueue_get_avail_bytes(vq, &bytes, NULL, 4096, 0); |
323 | return bytes; |
324 | } |
325 | |
326 | static void flush_queued_data_bh(void *opaque) |
327 | { |
328 | VirtIOSerialPort *port = opaque; |
329 | |
330 | flush_queued_data(port); |
331 | } |
332 | |
333 | void virtio_serial_throttle_port(VirtIOSerialPort *port, bool throttle) |
334 | { |
335 | if (!port) { |
336 | return; |
337 | } |
338 | |
339 | trace_virtio_serial_throttle_port(port->id, throttle); |
340 | port->throttled = throttle; |
341 | if (throttle) { |
342 | return; |
343 | } |
344 | qemu_bh_schedule(port->bh); |
345 | } |
346 | |
347 | /* Guest wants to notify us of some event */ |
348 | static void handle_control_message(VirtIOSerial *vser, void *buf, size_t len) |
349 | { |
350 | VirtIODevice *vdev = VIRTIO_DEVICE(vser); |
351 | struct VirtIOSerialPort *port; |
352 | VirtIOSerialPortClass *vsc; |
353 | struct virtio_console_control cpkt, *gcpkt; |
354 | uint8_t *buffer; |
355 | size_t buffer_len; |
356 | |
357 | gcpkt = buf; |
358 | |
359 | if (len < sizeof(cpkt)) { |
360 | /* The guest sent an invalid control packet */ |
361 | return; |
362 | } |
363 | |
364 | cpkt.event = virtio_lduw_p(vdev, &gcpkt->event); |
365 | cpkt.value = virtio_lduw_p(vdev, &gcpkt->value); |
366 | |
367 | trace_virtio_serial_handle_control_message(cpkt.event, cpkt.value); |
368 | |
369 | if (cpkt.event == VIRTIO_CONSOLE_DEVICE_READY) { |
370 | if (!cpkt.value) { |
371 | error_report("virtio-serial-bus: Guest failure in adding device %s" , |
372 | vser->bus.qbus.name); |
373 | return; |
374 | } |
375 | /* |
376 | * The device is up, we can now tell the device about all the |
377 | * ports we have here. |
378 | */ |
379 | QTAILQ_FOREACH(port, &vser->ports, next) { |
380 | send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_ADD, 1); |
381 | } |
382 | return; |
383 | } |
384 | |
385 | port = find_port_by_id(vser, virtio_ldl_p(vdev, &gcpkt->id)); |
386 | if (!port) { |
387 | error_report("virtio-serial-bus: Unexpected port id %u for device %s" , |
388 | virtio_ldl_p(vdev, &gcpkt->id), vser->bus.qbus.name); |
389 | return; |
390 | } |
391 | |
392 | trace_virtio_serial_handle_control_message_port(port->id); |
393 | |
394 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
395 | |
396 | switch(cpkt.event) { |
397 | case VIRTIO_CONSOLE_PORT_READY: |
398 | if (!cpkt.value) { |
399 | error_report("virtio-serial-bus: Guest failure in adding port %u for device %s" , |
400 | port->id, vser->bus.qbus.name); |
401 | break; |
402 | } |
403 | /* |
404 | * Now that we know the guest asked for the port name, we're |
405 | * sure the guest has initialised whatever state is necessary |
406 | * for this port. Now's a good time to let the guest know if |
407 | * this port is a console port so that the guest can hook it |
408 | * up to hvc. |
409 | */ |
410 | if (vsc->is_console) { |
411 | send_control_event(vser, port->id, VIRTIO_CONSOLE_CONSOLE_PORT, 1); |
412 | } |
413 | |
414 | if (port->name) { |
415 | virtio_stl_p(vdev, &cpkt.id, port->id); |
416 | virtio_stw_p(vdev, &cpkt.event, VIRTIO_CONSOLE_PORT_NAME); |
417 | virtio_stw_p(vdev, &cpkt.value, 1); |
418 | |
419 | buffer_len = sizeof(cpkt) + strlen(port->name) + 1; |
420 | buffer = g_malloc(buffer_len); |
421 | |
422 | memcpy(buffer, &cpkt, sizeof(cpkt)); |
423 | memcpy(buffer + sizeof(cpkt), port->name, strlen(port->name)); |
424 | buffer[buffer_len - 1] = 0; |
425 | |
426 | send_control_msg(vser, buffer, buffer_len); |
427 | g_free(buffer); |
428 | } |
429 | |
430 | if (port->host_connected) { |
431 | send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_OPEN, 1); |
432 | } |
433 | |
434 | /* |
435 | * When the guest has asked us for this information it means |
436 | * the guest is all setup and has its virtqueues |
437 | * initialised. If some app is interested in knowing about |
438 | * this event, let it know. |
439 | */ |
440 | if (vsc->guest_ready) { |
441 | vsc->guest_ready(port); |
442 | } |
443 | break; |
444 | |
445 | case VIRTIO_CONSOLE_PORT_OPEN: |
446 | port->guest_connected = cpkt.value; |
447 | if (vsc->set_guest_connected) { |
448 | /* Send the guest opened notification if an app is interested */ |
449 | vsc->set_guest_connected(port, cpkt.value); |
450 | } |
451 | break; |
452 | } |
453 | } |
454 | |
455 | static void control_in(VirtIODevice *vdev, VirtQueue *vq) |
456 | { |
457 | } |
458 | |
459 | static void control_out(VirtIODevice *vdev, VirtQueue *vq) |
460 | { |
461 | VirtQueueElement *elem; |
462 | VirtIOSerial *vser; |
463 | uint8_t *buf; |
464 | size_t len; |
465 | |
466 | vser = VIRTIO_SERIAL(vdev); |
467 | |
468 | len = 0; |
469 | buf = NULL; |
470 | for (;;) { |
471 | size_t cur_len; |
472 | |
473 | elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); |
474 | if (!elem) { |
475 | break; |
476 | } |
477 | |
478 | cur_len = iov_size(elem->out_sg, elem->out_num); |
479 | /* |
480 | * Allocate a new buf only if we didn't have one previously or |
481 | * if the size of the buf differs |
482 | */ |
483 | if (cur_len > len) { |
484 | g_free(buf); |
485 | |
486 | buf = g_malloc(cur_len); |
487 | len = cur_len; |
488 | } |
489 | iov_to_buf(elem->out_sg, elem->out_num, 0, buf, cur_len); |
490 | |
491 | handle_control_message(vser, buf, cur_len); |
492 | virtqueue_push(vq, elem, 0); |
493 | g_free(elem); |
494 | } |
495 | g_free(buf); |
496 | virtio_notify(vdev, vq); |
497 | } |
498 | |
499 | /* Guest wrote something to some port. */ |
500 | static void handle_output(VirtIODevice *vdev, VirtQueue *vq) |
501 | { |
502 | VirtIOSerial *vser; |
503 | VirtIOSerialPort *port; |
504 | |
505 | vser = VIRTIO_SERIAL(vdev); |
506 | port = find_port_by_vq(vser, vq); |
507 | |
508 | if (!port || !port->host_connected) { |
509 | discard_vq_data(vq, vdev); |
510 | return; |
511 | } |
512 | |
513 | if (!port->throttled) { |
514 | do_flush_queued_data(port, vq, vdev); |
515 | return; |
516 | } |
517 | } |
518 | |
519 | static void handle_input(VirtIODevice *vdev, VirtQueue *vq) |
520 | { |
521 | /* |
522 | * Users of virtio-serial would like to know when guest becomes |
523 | * writable again -- i.e. if a vq had stuff queued up and the |
524 | * guest wasn't reading at all, the host would not be able to |
525 | * write to the vq anymore. Once the guest reads off something, |
526 | * we can start queueing things up again. However, this call is |
527 | * made for each buffer addition by the guest -- even though free |
528 | * buffers existed prior to the current buffer addition. This is |
529 | * done so as not to maintain previous state, which will need |
530 | * additional live-migration-related changes. |
531 | */ |
532 | VirtIOSerial *vser; |
533 | VirtIOSerialPort *port; |
534 | VirtIOSerialPortClass *vsc; |
535 | |
536 | vser = VIRTIO_SERIAL(vdev); |
537 | port = find_port_by_vq(vser, vq); |
538 | |
539 | if (!port) { |
540 | return; |
541 | } |
542 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
543 | |
544 | /* |
545 | * If guest_connected is false, this call is being made by the |
546 | * early-boot queueing up of descriptors, which is just noise for |
547 | * the host apps -- don't disturb them in that case. |
548 | */ |
549 | if (port->guest_connected && port->host_connected && vsc->guest_writable) { |
550 | vsc->guest_writable(port); |
551 | } |
552 | } |
553 | |
554 | static uint64_t get_features(VirtIODevice *vdev, uint64_t features, |
555 | Error **errp) |
556 | { |
557 | VirtIOSerial *vser; |
558 | |
559 | vser = VIRTIO_SERIAL(vdev); |
560 | |
561 | features |= vser->host_features; |
562 | if (vser->bus.max_nr_ports > 1) { |
563 | virtio_add_feature(&features, VIRTIO_CONSOLE_F_MULTIPORT); |
564 | } |
565 | return features; |
566 | } |
567 | |
568 | /* Guest requested config info */ |
569 | static void get_config(VirtIODevice *vdev, uint8_t *config_data) |
570 | { |
571 | VirtIOSerial *vser = VIRTIO_SERIAL(vdev); |
572 | struct virtio_console_config *config = |
573 | (struct virtio_console_config *)config_data; |
574 | |
575 | config->cols = 0; |
576 | config->rows = 0; |
577 | config->max_nr_ports = virtio_tswap32(vdev, |
578 | vser->serial.max_virtserial_ports); |
579 | } |
580 | |
581 | /* Guest sent new config info */ |
582 | static void set_config(VirtIODevice *vdev, const uint8_t *config_data) |
583 | { |
584 | VirtIOSerial *vser = VIRTIO_SERIAL(vdev); |
585 | struct virtio_console_config *config = |
586 | (struct virtio_console_config *)config_data; |
587 | VirtIOSerialPort *port = find_first_connected_console(vser); |
588 | VirtIOSerialPortClass *vsc; |
589 | uint8_t emerg_wr_lo; |
590 | |
591 | if (!virtio_has_feature(vser->host_features, |
592 | VIRTIO_CONSOLE_F_EMERG_WRITE) || !config->emerg_wr) { |
593 | return; |
594 | } |
595 | |
596 | emerg_wr_lo = le32_to_cpu(config->emerg_wr); |
597 | /* Make sure we don't misdetect an emergency write when the guest |
598 | * does a short config write after an emergency write. */ |
599 | config->emerg_wr = 0; |
600 | if (!port) { |
601 | return; |
602 | } |
603 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
604 | (void)vsc->have_data(port, &emerg_wr_lo, 1); |
605 | } |
606 | |
607 | static void guest_reset(VirtIOSerial *vser) |
608 | { |
609 | VirtIOSerialPort *port; |
610 | VirtIOSerialPortClass *vsc; |
611 | |
612 | QTAILQ_FOREACH(port, &vser->ports, next) { |
613 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
614 | |
615 | discard_throttle_data(port); |
616 | |
617 | if (port->guest_connected) { |
618 | port->guest_connected = false; |
619 | if (vsc->set_guest_connected) { |
620 | vsc->set_guest_connected(port, false); |
621 | } |
622 | } |
623 | } |
624 | } |
625 | |
626 | static void set_status(VirtIODevice *vdev, uint8_t status) |
627 | { |
628 | VirtIOSerial *vser; |
629 | VirtIOSerialPort *port; |
630 | |
631 | vser = VIRTIO_SERIAL(vdev); |
632 | port = find_port_by_id(vser, 0); |
633 | |
634 | if (port && !use_multiport(port->vser) |
635 | && (status & VIRTIO_CONFIG_S_DRIVER_OK)) { |
636 | /* |
637 | * Non-multiport guests won't be able to tell us guest |
638 | * open/close status. Such guests can only have a port at id |
639 | * 0, so set guest_connected for such ports as soon as guest |
640 | * is up. |
641 | */ |
642 | port->guest_connected = true; |
643 | } |
644 | if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { |
645 | guest_reset(vser); |
646 | } |
647 | |
648 | QTAILQ_FOREACH(port, &vser->ports, next) { |
649 | VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
650 | if (vsc->enable_backend) { |
651 | vsc->enable_backend(port, vdev->vm_running); |
652 | } |
653 | } |
654 | } |
655 | |
656 | static void vser_reset(VirtIODevice *vdev) |
657 | { |
658 | VirtIOSerial *vser; |
659 | |
660 | vser = VIRTIO_SERIAL(vdev); |
661 | guest_reset(vser); |
662 | } |
663 | |
664 | static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f) |
665 | { |
666 | VirtIOSerial *s = VIRTIO_SERIAL(vdev); |
667 | VirtIOSerialPort *port; |
668 | uint32_t nr_active_ports; |
669 | unsigned int i, max_nr_ports; |
670 | struct virtio_console_config config; |
671 | |
672 | /* The config space (ignored on the far end in current versions) */ |
673 | get_config(vdev, (uint8_t *)&config); |
674 | qemu_put_be16(f, config.cols); |
675 | qemu_put_be16(f, config.rows); |
676 | qemu_put_be32(f, config.max_nr_ports); |
677 | |
678 | /* The ports map */ |
679 | max_nr_ports = s->serial.max_virtserial_ports; |
680 | for (i = 0; i < DIV_ROUND_UP(max_nr_ports, 32); i++) { |
681 | qemu_put_be32s(f, &s->ports_map[i]); |
682 | } |
683 | |
684 | /* Ports */ |
685 | |
686 | nr_active_ports = 0; |
687 | QTAILQ_FOREACH(port, &s->ports, next) { |
688 | nr_active_ports++; |
689 | } |
690 | |
691 | qemu_put_be32s(f, &nr_active_ports); |
692 | |
693 | /* |
694 | * Items in struct VirtIOSerialPort. |
695 | */ |
696 | QTAILQ_FOREACH(port, &s->ports, next) { |
697 | uint32_t elem_popped; |
698 | |
699 | qemu_put_be32s(f, &port->id); |
700 | qemu_put_byte(f, port->guest_connected); |
701 | qemu_put_byte(f, port->host_connected); |
702 | |
703 | elem_popped = 0; |
704 | if (port->elem) { |
705 | elem_popped = 1; |
706 | } |
707 | qemu_put_be32s(f, &elem_popped); |
708 | if (elem_popped) { |
709 | qemu_put_be32s(f, &port->iov_idx); |
710 | qemu_put_be64s(f, &port->iov_offset); |
711 | qemu_put_virtqueue_element(f, port->elem); |
712 | } |
713 | } |
714 | } |
715 | |
716 | static void virtio_serial_post_load_timer_cb(void *opaque) |
717 | { |
718 | uint32_t i; |
719 | VirtIOSerial *s = VIRTIO_SERIAL(opaque); |
720 | VirtIOSerialPort *port; |
721 | uint8_t host_connected; |
722 | VirtIOSerialPortClass *vsc; |
723 | |
724 | if (!s->post_load) { |
725 | return; |
726 | } |
727 | for (i = 0 ; i < s->post_load->nr_active_ports; ++i) { |
728 | port = s->post_load->connected[i].port; |
729 | host_connected = s->post_load->connected[i].host_connected; |
730 | if (host_connected != port->host_connected) { |
731 | /* |
732 | * We have to let the guest know of the host connection |
733 | * status change |
734 | */ |
735 | send_control_event(s, port->id, VIRTIO_CONSOLE_PORT_OPEN, |
736 | port->host_connected); |
737 | } |
738 | vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
739 | if (vsc->set_guest_connected) { |
740 | vsc->set_guest_connected(port, port->guest_connected); |
741 | } |
742 | } |
743 | g_free(s->post_load->connected); |
744 | timer_del(s->post_load->timer); |
745 | timer_free(s->post_load->timer); |
746 | g_free(s->post_load); |
747 | s->post_load = NULL; |
748 | } |
749 | |
750 | static int fetch_active_ports_list(QEMUFile *f, |
751 | VirtIOSerial *s, uint32_t nr_active_ports) |
752 | { |
753 | VirtIODevice *vdev = VIRTIO_DEVICE(s); |
754 | uint32_t i; |
755 | |
756 | s->post_load = g_malloc0(sizeof(*s->post_load)); |
757 | s->post_load->nr_active_ports = nr_active_ports; |
758 | s->post_load->connected = |
759 | g_malloc0(sizeof(*s->post_load->connected) * nr_active_ports); |
760 | |
761 | s->post_load->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, |
762 | virtio_serial_post_load_timer_cb, |
763 | s); |
764 | |
765 | /* Items in struct VirtIOSerialPort */ |
766 | for (i = 0; i < nr_active_ports; i++) { |
767 | VirtIOSerialPort *port; |
768 | uint32_t elem_popped; |
769 | uint32_t id; |
770 | |
771 | id = qemu_get_be32(f); |
772 | port = find_port_by_id(s, id); |
773 | if (!port) { |
774 | return -EINVAL; |
775 | } |
776 | |
777 | port->guest_connected = qemu_get_byte(f); |
778 | s->post_load->connected[i].port = port; |
779 | s->post_load->connected[i].host_connected = qemu_get_byte(f); |
780 | |
781 | qemu_get_be32s(f, &elem_popped); |
782 | if (elem_popped) { |
783 | qemu_get_be32s(f, &port->iov_idx); |
784 | qemu_get_be64s(f, &port->iov_offset); |
785 | |
786 | port->elem = |
787 | qemu_get_virtqueue_element(vdev, f, sizeof(VirtQueueElement)); |
788 | |
789 | /* |
790 | * Port was throttled on source machine. Let's |
791 | * unthrottle it here so data starts flowing again. |
792 | */ |
793 | virtio_serial_throttle_port(port, false); |
794 | } |
795 | } |
796 | timer_mod(s->post_load->timer, 1); |
797 | return 0; |
798 | } |
799 | |
800 | static int virtio_serial_load_device(VirtIODevice *vdev, QEMUFile *f, |
801 | int version_id) |
802 | { |
803 | VirtIOSerial *s = VIRTIO_SERIAL(vdev); |
804 | uint32_t max_nr_ports, nr_active_ports, ports_map; |
805 | unsigned int i; |
806 | int ret; |
807 | uint32_t tmp; |
808 | |
809 | /* Unused */ |
810 | qemu_get_be16s(f, (uint16_t *) &tmp); |
811 | qemu_get_be16s(f, (uint16_t *) &tmp); |
812 | qemu_get_be32s(f, &tmp); |
813 | |
814 | max_nr_ports = s->serial.max_virtserial_ports; |
815 | for (i = 0; i < DIV_ROUND_UP(max_nr_ports, 32); i++) { |
816 | qemu_get_be32s(f, &ports_map); |
817 | |
818 | if (ports_map != s->ports_map[i]) { |
819 | /* |
820 | * Ports active on source and destination don't |
821 | * match. Fail migration. |
822 | */ |
823 | return -EINVAL; |
824 | } |
825 | } |
826 | |
827 | qemu_get_be32s(f, &nr_active_ports); |
828 | |
829 | if (nr_active_ports) { |
830 | ret = fetch_active_ports_list(f, s, nr_active_ports); |
831 | if (ret) { |
832 | return ret; |
833 | } |
834 | } |
835 | return 0; |
836 | } |
837 | |
838 | static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent); |
839 | |
840 | static Property virtser_props[] = { |
841 | DEFINE_PROP_UINT32("nr" , VirtIOSerialPort, id, VIRTIO_CONSOLE_BAD_ID), |
842 | DEFINE_PROP_STRING("name" , VirtIOSerialPort, name), |
843 | DEFINE_PROP_END_OF_LIST() |
844 | }; |
845 | |
846 | #define TYPE_VIRTIO_SERIAL_BUS "virtio-serial-bus" |
847 | #define VIRTIO_SERIAL_BUS(obj) \ |
848 | OBJECT_CHECK(VirtIOSerialBus, (obj), TYPE_VIRTIO_SERIAL_BUS) |
849 | |
850 | static void virtser_bus_class_init(ObjectClass *klass, void *data) |
851 | { |
852 | BusClass *k = BUS_CLASS(klass); |
853 | k->print_dev = virtser_bus_dev_print; |
854 | } |
855 | |
856 | static const TypeInfo virtser_bus_info = { |
857 | .name = TYPE_VIRTIO_SERIAL_BUS, |
858 | .parent = TYPE_BUS, |
859 | .instance_size = sizeof(VirtIOSerialBus), |
860 | .class_init = virtser_bus_class_init, |
861 | }; |
862 | |
863 | static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent) |
864 | { |
865 | VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(qdev); |
866 | |
867 | monitor_printf(mon, "%*sport %d, guest %s, host %s, throttle %s\n" , |
868 | indent, "" , port->id, |
869 | port->guest_connected ? "on" : "off" , |
870 | port->host_connected ? "on" : "off" , |
871 | port->throttled ? "on" : "off" ); |
872 | } |
873 | |
874 | /* This function is only used if a port id is not provided by the user */ |
875 | static uint32_t find_free_port_id(VirtIOSerial *vser) |
876 | { |
877 | unsigned int i, max_nr_ports; |
878 | |
879 | max_nr_ports = vser->serial.max_virtserial_ports; |
880 | for (i = 0; i < DIV_ROUND_UP(max_nr_ports, 32); i++) { |
881 | uint32_t map, zeroes; |
882 | |
883 | map = vser->ports_map[i]; |
884 | zeroes = ctz32(~map); |
885 | if (zeroes != 32) { |
886 | return zeroes + i * 32; |
887 | } |
888 | } |
889 | return VIRTIO_CONSOLE_BAD_ID; |
890 | } |
891 | |
892 | static void mark_port_added(VirtIOSerial *vser, uint32_t port_id) |
893 | { |
894 | unsigned int i; |
895 | |
896 | i = port_id / 32; |
897 | vser->ports_map[i] |= 1U << (port_id % 32); |
898 | } |
899 | |
900 | static void add_port(VirtIOSerial *vser, uint32_t port_id) |
901 | { |
902 | mark_port_added(vser, port_id); |
903 | send_control_event(vser, port_id, VIRTIO_CONSOLE_PORT_ADD, 1); |
904 | } |
905 | |
906 | static void remove_port(VirtIOSerial *vser, uint32_t port_id) |
907 | { |
908 | VirtIOSerialPort *port; |
909 | |
910 | /* |
911 | * Don't mark port 0 removed -- we explicitly reserve it for |
912 | * backward compat with older guests, ensure a virtconsole device |
913 | * unplug retains the reservation. |
914 | */ |
915 | if (port_id) { |
916 | unsigned int i; |
917 | |
918 | i = port_id / 32; |
919 | vser->ports_map[i] &= ~(1U << (port_id % 32)); |
920 | } |
921 | |
922 | port = find_port_by_id(vser, port_id); |
923 | /* |
924 | * This function is only called from qdev's unplug callback; if we |
925 | * get a NULL port here, we're in trouble. |
926 | */ |
927 | assert(port); |
928 | |
929 | /* Flush out any unconsumed buffers first */ |
930 | discard_throttle_data(port); |
931 | discard_vq_data(port->ovq, VIRTIO_DEVICE(port->vser)); |
932 | |
933 | send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_REMOVE, 1); |
934 | } |
935 | |
936 | static void virtser_port_device_realize(DeviceState *dev, Error **errp) |
937 | { |
938 | VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); |
939 | VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port); |
940 | VirtIOSerialBus *bus = VIRTIO_SERIAL_BUS(qdev_get_parent_bus(dev)); |
941 | int max_nr_ports; |
942 | bool plugging_port0; |
943 | Error *err = NULL; |
944 | |
945 | port->vser = bus->vser; |
946 | port->bh = qemu_bh_new(flush_queued_data_bh, port); |
947 | |
948 | assert(vsc->have_data); |
949 | |
950 | /* |
951 | * Is the first console port we're seeing? If so, put it up at |
952 | * location 0. This is done for backward compatibility (old |
953 | * kernel, new qemu). |
954 | */ |
955 | plugging_port0 = vsc->is_console && !find_port_by_id(port->vser, 0); |
956 | |
957 | if (find_port_by_id(port->vser, port->id)) { |
958 | error_setg(errp, "virtio-serial-bus: A port already exists at id %u" , |
959 | port->id); |
960 | return; |
961 | } |
962 | |
963 | if (port->name != NULL && find_port_by_name(port->name)) { |
964 | error_setg(errp, "virtio-serial-bus: A port already exists by name %s" , |
965 | port->name); |
966 | return; |
967 | } |
968 | |
969 | if (port->id == VIRTIO_CONSOLE_BAD_ID) { |
970 | if (plugging_port0) { |
971 | port->id = 0; |
972 | } else { |
973 | port->id = find_free_port_id(port->vser); |
974 | if (port->id == VIRTIO_CONSOLE_BAD_ID) { |
975 | error_setg(errp, "virtio-serial-bus: Maximum port limit for " |
976 | "this device reached" ); |
977 | return; |
978 | } |
979 | } |
980 | } |
981 | |
982 | max_nr_ports = port->vser->serial.max_virtserial_ports; |
983 | if (port->id >= max_nr_ports) { |
984 | error_setg(errp, "virtio-serial-bus: Out-of-range port id specified, " |
985 | "max. allowed: %u" , max_nr_ports - 1); |
986 | return; |
987 | } |
988 | |
989 | vsc->realize(dev, &err); |
990 | if (err != NULL) { |
991 | error_propagate(errp, err); |
992 | return; |
993 | } |
994 | |
995 | port->elem = NULL; |
996 | } |
997 | |
998 | static void virtser_port_device_plug(HotplugHandler *hotplug_dev, |
999 | DeviceState *dev, Error **errp) |
1000 | { |
1001 | VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); |
1002 | |
1003 | QTAILQ_INSERT_TAIL(&port->vser->ports, port, next); |
1004 | port->ivq = port->vser->ivqs[port->id]; |
1005 | port->ovq = port->vser->ovqs[port->id]; |
1006 | |
1007 | add_port(port->vser, port->id); |
1008 | |
1009 | /* Send an update to the guest about this new port added */ |
1010 | virtio_notify_config(VIRTIO_DEVICE(hotplug_dev)); |
1011 | } |
1012 | |
1013 | static void virtser_port_device_unrealize(DeviceState *dev, Error **errp) |
1014 | { |
1015 | VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev); |
1016 | VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(dev); |
1017 | VirtIOSerial *vser = port->vser; |
1018 | |
1019 | qemu_bh_delete(port->bh); |
1020 | remove_port(port->vser, port->id); |
1021 | |
1022 | QTAILQ_REMOVE(&vser->ports, port, next); |
1023 | |
1024 | if (vsc->unrealize) { |
1025 | vsc->unrealize(dev, errp); |
1026 | } |
1027 | } |
1028 | |
1029 | static void virtio_serial_device_realize(DeviceState *dev, Error **errp) |
1030 | { |
1031 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
1032 | VirtIOSerial *vser = VIRTIO_SERIAL(dev); |
1033 | uint32_t i, max_supported_ports; |
1034 | size_t config_size = sizeof(struct virtio_console_config); |
1035 | |
1036 | if (!vser->serial.max_virtserial_ports) { |
1037 | error_setg(errp, "Maximum number of serial ports not specified" ); |
1038 | return; |
1039 | } |
1040 | |
1041 | /* Each port takes 2 queues, and one pair is for the control queue */ |
1042 | max_supported_ports = VIRTIO_QUEUE_MAX / 2 - 1; |
1043 | |
1044 | if (vser->serial.max_virtserial_ports > max_supported_ports) { |
1045 | error_setg(errp, "maximum ports supported: %u" , max_supported_ports); |
1046 | return; |
1047 | } |
1048 | |
1049 | if (!virtio_has_feature(vser->host_features, |
1050 | VIRTIO_CONSOLE_F_EMERG_WRITE)) { |
1051 | config_size = offsetof(struct virtio_console_config, emerg_wr); |
1052 | } |
1053 | virtio_init(vdev, "virtio-serial" , VIRTIO_ID_CONSOLE, |
1054 | config_size); |
1055 | |
1056 | /* Spawn a new virtio-serial bus on which the ports will ride as devices */ |
1057 | qbus_create_inplace(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, |
1058 | dev, vdev->bus_name); |
1059 | qbus_set_hotplug_handler(BUS(&vser->bus), OBJECT(vser), errp); |
1060 | vser->bus.vser = vser; |
1061 | QTAILQ_INIT(&vser->ports); |
1062 | |
1063 | vser->bus.max_nr_ports = vser->serial.max_virtserial_ports; |
1064 | vser->ivqs = g_malloc(vser->serial.max_virtserial_ports |
1065 | * sizeof(VirtQueue *)); |
1066 | vser->ovqs = g_malloc(vser->serial.max_virtserial_ports |
1067 | * sizeof(VirtQueue *)); |
1068 | |
1069 | /* Add a queue for host to guest transfers for port 0 (backward compat) */ |
1070 | vser->ivqs[0] = virtio_add_queue(vdev, 128, handle_input); |
1071 | /* Add a queue for guest to host transfers for port 0 (backward compat) */ |
1072 | vser->ovqs[0] = virtio_add_queue(vdev, 128, handle_output); |
1073 | |
1074 | /* TODO: host to guest notifications can get dropped |
1075 | * if the queue fills up. Implement queueing in host, |
1076 | * this might also make it possible to reduce the control |
1077 | * queue size: as guest preposts buffers there, |
1078 | * this will save 4Kbyte of guest memory per entry. */ |
1079 | |
1080 | /* control queue: host to guest */ |
1081 | vser->c_ivq = virtio_add_queue(vdev, 32, control_in); |
1082 | /* control queue: guest to host */ |
1083 | vser->c_ovq = virtio_add_queue(vdev, 32, control_out); |
1084 | |
1085 | for (i = 1; i < vser->bus.max_nr_ports; i++) { |
1086 | /* Add a per-port queue for host to guest transfers */ |
1087 | vser->ivqs[i] = virtio_add_queue(vdev, 128, handle_input); |
1088 | /* Add a per-per queue for guest to host transfers */ |
1089 | vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output); |
1090 | } |
1091 | |
1092 | vser->ports_map = g_malloc0((DIV_ROUND_UP(vser->serial.max_virtserial_ports, 32)) |
1093 | * sizeof(vser->ports_map[0])); |
1094 | /* |
1095 | * Reserve location 0 for a console port for backward compat |
1096 | * (old kernel, new qemu) |
1097 | */ |
1098 | mark_port_added(vser, 0); |
1099 | |
1100 | vser->post_load = NULL; |
1101 | |
1102 | QLIST_INSERT_HEAD(&vserdevices.devices, vser, next); |
1103 | } |
1104 | |
1105 | static void virtio_serial_port_class_init(ObjectClass *klass, void *data) |
1106 | { |
1107 | DeviceClass *k = DEVICE_CLASS(klass); |
1108 | |
1109 | set_bit(DEVICE_CATEGORY_INPUT, k->categories); |
1110 | k->bus_type = TYPE_VIRTIO_SERIAL_BUS; |
1111 | k->realize = virtser_port_device_realize; |
1112 | k->unrealize = virtser_port_device_unrealize; |
1113 | k->props = virtser_props; |
1114 | } |
1115 | |
1116 | static const TypeInfo virtio_serial_port_type_info = { |
1117 | .name = TYPE_VIRTIO_SERIAL_PORT, |
1118 | .parent = TYPE_DEVICE, |
1119 | .instance_size = sizeof(VirtIOSerialPort), |
1120 | .abstract = true, |
1121 | .class_size = sizeof(VirtIOSerialPortClass), |
1122 | .class_init = virtio_serial_port_class_init, |
1123 | }; |
1124 | |
1125 | static void virtio_serial_device_unrealize(DeviceState *dev, Error **errp) |
1126 | { |
1127 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
1128 | VirtIOSerial *vser = VIRTIO_SERIAL(dev); |
1129 | |
1130 | QLIST_REMOVE(vser, next); |
1131 | |
1132 | g_free(vser->ivqs); |
1133 | g_free(vser->ovqs); |
1134 | g_free(vser->ports_map); |
1135 | if (vser->post_load) { |
1136 | g_free(vser->post_load->connected); |
1137 | timer_del(vser->post_load->timer); |
1138 | timer_free(vser->post_load->timer); |
1139 | g_free(vser->post_load); |
1140 | } |
1141 | |
1142 | qbus_set_hotplug_handler(BUS(&vser->bus), NULL, errp); |
1143 | |
1144 | virtio_cleanup(vdev); |
1145 | } |
1146 | |
1147 | /* Note: 'console' is used for backwards compatibility */ |
1148 | static const VMStateDescription vmstate_virtio_console = { |
1149 | .name = "virtio-console" , |
1150 | .minimum_version_id = 3, |
1151 | .version_id = 3, |
1152 | .fields = (VMStateField[]) { |
1153 | VMSTATE_VIRTIO_DEVICE, |
1154 | VMSTATE_END_OF_LIST() |
1155 | }, |
1156 | }; |
1157 | |
1158 | static Property virtio_serial_properties[] = { |
1159 | DEFINE_PROP_UINT32("max_ports" , VirtIOSerial, serial.max_virtserial_ports, |
1160 | 31), |
1161 | DEFINE_PROP_BIT64("emergency-write" , VirtIOSerial, host_features, |
1162 | VIRTIO_CONSOLE_F_EMERG_WRITE, true), |
1163 | DEFINE_PROP_END_OF_LIST(), |
1164 | }; |
1165 | |
1166 | static void virtio_serial_class_init(ObjectClass *klass, void *data) |
1167 | { |
1168 | DeviceClass *dc = DEVICE_CLASS(klass); |
1169 | VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); |
1170 | HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); |
1171 | |
1172 | QLIST_INIT(&vserdevices.devices); |
1173 | |
1174 | dc->props = virtio_serial_properties; |
1175 | dc->vmsd = &vmstate_virtio_console; |
1176 | set_bit(DEVICE_CATEGORY_INPUT, dc->categories); |
1177 | vdc->realize = virtio_serial_device_realize; |
1178 | vdc->unrealize = virtio_serial_device_unrealize; |
1179 | vdc->get_features = get_features; |
1180 | vdc->get_config = get_config; |
1181 | vdc->set_config = set_config; |
1182 | vdc->set_status = set_status; |
1183 | vdc->reset = vser_reset; |
1184 | vdc->save = virtio_serial_save_device; |
1185 | vdc->load = virtio_serial_load_device; |
1186 | hc->plug = virtser_port_device_plug; |
1187 | hc->unplug = qdev_simple_device_unplug_cb; |
1188 | } |
1189 | |
1190 | static const TypeInfo virtio_device_info = { |
1191 | .name = TYPE_VIRTIO_SERIAL, |
1192 | .parent = TYPE_VIRTIO_DEVICE, |
1193 | .instance_size = sizeof(VirtIOSerial), |
1194 | .class_init = virtio_serial_class_init, |
1195 | .interfaces = (InterfaceInfo[]) { |
1196 | { TYPE_HOTPLUG_HANDLER }, |
1197 | { } |
1198 | } |
1199 | }; |
1200 | |
1201 | static void virtio_serial_register_types(void) |
1202 | { |
1203 | type_register_static(&virtser_bus_info); |
1204 | type_register_static(&virtio_serial_port_type_info); |
1205 | type_register_static(&virtio_device_info); |
1206 | } |
1207 | |
1208 | type_init(virtio_serial_register_types) |
1209 | |