2 * A bus for connecting virtio serial and console ports
4 * Copyright (C) 2009, 2010 Red Hat, Inc.
7 * Amit Shah <amit.shah@redhat.com>
9 * Some earlier parts are:
10 * Copyright IBM, Corp. 2008
12 * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
14 * This work is licensed under the terms of the GNU GPL, version 2. See
15 * the COPYING file in the top-level directory.
20 #include "qemu-queue.h"
22 #include "virtio-serial.h"
24 /* The virtio-serial bus on top of which the ports will ride as devices */
25 struct VirtIOSerialBus
{
28 /* This is the parent device that provides the bus for ports. */
31 /* The maximum number of ports that can ride on top of this bus */
32 uint32_t max_nr_ports
;
38 VirtQueue
*c_ivq
, *c_ovq
;
39 /* Arrays of ivqs and ovqs: one per port */
40 VirtQueue
**ivqs
, **ovqs
;
46 QTAILQ_HEAD(, VirtIOSerialPort
) ports
;
48 /* bitmap for identifying active ports */
51 struct virtio_console_config config
;
54 static VirtIOSerialPort
*find_port_by_id(VirtIOSerial
*vser
, uint32_t id
)
56 VirtIOSerialPort
*port
;
58 if (id
== VIRTIO_CONSOLE_BAD_ID
) {
62 QTAILQ_FOREACH(port
, &vser
->ports
, next
) {
69 static VirtIOSerialPort
*find_port_by_vq(VirtIOSerial
*vser
, VirtQueue
*vq
)
71 VirtIOSerialPort
*port
;
73 QTAILQ_FOREACH(port
, &vser
->ports
, next
) {
74 if (port
->ivq
== vq
|| port
->ovq
== vq
)
80 static bool use_multiport(VirtIOSerial
*vser
)
82 return vser
->vdev
.guest_features
& (1 << VIRTIO_CONSOLE_F_MULTIPORT
);
85 static size_t write_to_port(VirtIOSerialPort
*port
,
86 const uint8_t *buf
, size_t size
)
88 VirtQueueElement elem
;
93 if (!virtio_queue_ready(vq
)) {
98 while (offset
< size
) {
101 if (!virtqueue_pop(vq
, &elem
)) {
105 len
= iov_from_buf(elem
.in_sg
, elem
.in_num
,
106 buf
+ offset
, size
- offset
);
109 virtqueue_push(vq
, &elem
, len
);
112 virtio_notify(&port
->vser
->vdev
, vq
);
116 static void discard_vq_data(VirtQueue
*vq
, VirtIODevice
*vdev
)
118 VirtQueueElement elem
;
120 if (!virtio_queue_ready(vq
)) {
123 while (virtqueue_pop(vq
, &elem
)) {
124 virtqueue_push(vq
, &elem
, 0);
126 virtio_notify(vdev
, vq
);
129 static void do_flush_queued_data(VirtIOSerialPort
*port
, VirtQueue
*vq
,
132 VirtIOSerialPortInfo
*info
;
135 assert(virtio_queue_ready(vq
));
137 info
= DO_UPCAST(VirtIOSerialPortInfo
, qdev
, port
->dev
.info
);
139 while (!port
->throttled
) {
142 /* Pop an elem only if we haven't left off a previous one mid-way */
143 if (!port
->elem
.out_num
) {
144 if (!virtqueue_pop(vq
, &port
->elem
)) {
148 port
->iov_offset
= 0;
151 for (i
= port
->iov_idx
; i
< port
->elem
.out_num
; i
++) {
155 buf_size
= port
->elem
.out_sg
[i
].iov_len
- port
->iov_offset
;
156 ret
= info
->have_data(port
,
157 port
->elem
.out_sg
[i
].iov_base
160 if (ret
< 0 && ret
!= -EAGAIN
) {
161 /* We don't handle any other type of errors here */
164 if (ret
== -EAGAIN
|| (ret
>= 0 && ret
< buf_size
)) {
165 virtio_serial_throttle_port(port
, true);
168 port
->iov_offset
+= ret
;
172 port
->iov_offset
= 0;
174 if (port
->throttled
) {
177 virtqueue_push(vq
, &port
->elem
, 0);
178 port
->elem
.out_num
= 0;
180 virtio_notify(vdev
, vq
);
183 static void flush_queued_data(VirtIOSerialPort
*port
)
187 if (!virtio_queue_ready(port
->ovq
)) {
190 do_flush_queued_data(port
, port
->ovq
, &port
->vser
->vdev
);
193 static size_t send_control_msg(VirtIOSerialPort
*port
, void *buf
, size_t len
)
195 VirtQueueElement elem
;
197 struct virtio_console_control
*cpkt
;
199 vq
= port
->vser
->c_ivq
;
200 if (!virtio_queue_ready(vq
)) {
203 if (!virtqueue_pop(vq
, &elem
)) {
207 cpkt
= (struct virtio_console_control
*)buf
;
208 stl_p(&cpkt
->id
, port
->id
);
209 memcpy(elem
.in_sg
[0].iov_base
, buf
, len
);
211 virtqueue_push(vq
, &elem
, len
);
212 virtio_notify(&port
->vser
->vdev
, vq
);
216 static size_t send_control_event(VirtIOSerialPort
*port
, uint16_t event
,
219 struct virtio_console_control cpkt
;
221 stw_p(&cpkt
.event
, event
);
222 stw_p(&cpkt
.value
, value
);
224 return send_control_msg(port
, &cpkt
, sizeof(cpkt
));
227 /* Functions for use inside qemu to open and read from/write to ports */
228 int virtio_serial_open(VirtIOSerialPort
*port
)
230 /* Don't allow opening an already-open port */
231 if (port
->host_connected
) {
234 /* Send port open notification to the guest */
235 port
->host_connected
= true;
236 send_control_event(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
241 int virtio_serial_close(VirtIOSerialPort
*port
)
243 port
->host_connected
= false;
245 * If there's any data the guest sent which the app didn't
246 * consume, reset the throttling flag and discard the data.
248 port
->throttled
= false;
249 discard_vq_data(port
->ovq
, &port
->vser
->vdev
);
251 send_control_event(port
, VIRTIO_CONSOLE_PORT_OPEN
, 0);
256 /* Individual ports/apps call this function to write to the guest. */
257 ssize_t
virtio_serial_write(VirtIOSerialPort
*port
, const uint8_t *buf
,
260 if (!port
|| !port
->host_connected
|| !port
->guest_connected
) {
263 return write_to_port(port
, buf
, size
);
267 * Readiness of the guest to accept data on a port.
268 * Returns max. data the guest can receive
270 size_t virtio_serial_guest_ready(VirtIOSerialPort
*port
)
272 VirtQueue
*vq
= port
->ivq
;
274 if (!virtio_queue_ready(vq
) ||
275 !(port
->vser
->vdev
.status
& VIRTIO_CONFIG_S_DRIVER_OK
) ||
276 virtio_queue_empty(vq
)) {
279 if (use_multiport(port
->vser
) && !port
->guest_connected
) {
283 if (virtqueue_avail_bytes(vq
, 4096, 0)) {
286 if (virtqueue_avail_bytes(vq
, 1, 0)) {
292 static void flush_queued_data_bh(void *opaque
)
294 VirtIOSerialPort
*port
= opaque
;
296 flush_queued_data(port
);
299 void virtio_serial_throttle_port(VirtIOSerialPort
*port
, bool throttle
)
305 port
->throttled
= throttle
;
309 qemu_bh_schedule(port
->bh
);
312 /* Guest wants to notify us of some event */
313 static void handle_control_message(VirtIOSerial
*vser
, void *buf
, size_t len
)
315 struct VirtIOSerialPort
*port
;
316 struct VirtIOSerialPortInfo
*info
;
317 struct virtio_console_control cpkt
, *gcpkt
;
323 if (len
< sizeof(cpkt
)) {
324 /* The guest sent an invalid control packet */
328 cpkt
.event
= lduw_p(&gcpkt
->event
);
329 cpkt
.value
= lduw_p(&gcpkt
->value
);
331 if (cpkt
.event
== VIRTIO_CONSOLE_DEVICE_READY
) {
333 error_report("virtio-serial-bus: Guest failure in adding device %s",
334 vser
->bus
.qbus
.name
);
338 * The device is up, we can now tell the device about all the
339 * ports we have here.
341 QTAILQ_FOREACH(port
, &vser
->ports
, next
) {
342 send_control_event(port
, VIRTIO_CONSOLE_PORT_ADD
, 1);
347 port
= find_port_by_id(vser
, ldl_p(&gcpkt
->id
));
349 error_report("virtio-serial-bus: Unexpected port id %u for device %s\n",
350 ldl_p(&gcpkt
->id
), vser
->bus
.qbus
.name
);
354 info
= DO_UPCAST(VirtIOSerialPortInfo
, qdev
, port
->dev
.info
);
357 case VIRTIO_CONSOLE_PORT_READY
:
359 error_report("virtio-serial-bus: Guest failure in adding port %u for device %s",
360 port
->id
, vser
->bus
.qbus
.name
);
364 * Now that we know the guest asked for the port name, we're
365 * sure the guest has initialised whatever state is necessary
366 * for this port. Now's a good time to let the guest know if
367 * this port is a console port so that the guest can hook it
370 if (info
->is_console
) {
371 send_control_event(port
, VIRTIO_CONSOLE_CONSOLE_PORT
, 1);
375 stw_p(&cpkt
.event
, VIRTIO_CONSOLE_PORT_NAME
);
376 stw_p(&cpkt
.value
, 1);
378 buffer_len
= sizeof(cpkt
) + strlen(port
->name
) + 1;
379 buffer
= qemu_malloc(buffer_len
);
381 memcpy(buffer
, &cpkt
, sizeof(cpkt
));
382 memcpy(buffer
+ sizeof(cpkt
), port
->name
, strlen(port
->name
));
383 buffer
[buffer_len
- 1] = 0;
385 send_control_msg(port
, buffer
, buffer_len
);
389 if (port
->host_connected
) {
390 send_control_event(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
394 * When the guest has asked us for this information it means
395 * the guest is all setup and has its virtqueues
396 * initialised. If some app is interested in knowing about
397 * this event, let it know.
399 if (info
->guest_ready
) {
400 info
->guest_ready(port
);
404 case VIRTIO_CONSOLE_PORT_OPEN
:
405 port
->guest_connected
= cpkt
.value
;
406 if (cpkt
.value
&& info
->guest_open
) {
407 /* Send the guest opened notification if an app is interested */
408 info
->guest_open(port
);
411 if (!cpkt
.value
&& info
->guest_close
) {
412 /* Send the guest closed notification if an app is interested */
413 info
->guest_close(port
);
419 static void control_in(VirtIODevice
*vdev
, VirtQueue
*vq
)
423 static void control_out(VirtIODevice
*vdev
, VirtQueue
*vq
)
425 VirtQueueElement elem
;
430 vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
434 while (virtqueue_pop(vq
, &elem
)) {
435 size_t cur_len
, copied
;
437 cur_len
= iov_size(elem
.out_sg
, elem
.out_num
);
439 * Allocate a new buf only if we didn't have one previously or
440 * if the size of the buf differs
445 buf
= qemu_malloc(cur_len
);
448 copied
= iov_to_buf(elem
.out_sg
, elem
.out_num
, buf
, 0, len
);
450 handle_control_message(vser
, buf
, copied
);
451 virtqueue_push(vq
, &elem
, 0);
454 virtio_notify(vdev
, vq
);
457 /* Guest wrote something to some port. */
458 static void handle_output(VirtIODevice
*vdev
, VirtQueue
*vq
)
461 VirtIOSerialPort
*port
;
462 VirtIOSerialPortInfo
*info
;
464 vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
465 port
= find_port_by_vq(vser
, vq
);
466 info
= port
? DO_UPCAST(VirtIOSerialPortInfo
, qdev
, port
->dev
.info
) : NULL
;
468 if (!port
|| !port
->host_connected
|| !info
->have_data
) {
469 discard_vq_data(vq
, vdev
);
473 if (!port
->throttled
) {
474 do_flush_queued_data(port
, vq
, vdev
);
479 static void handle_input(VirtIODevice
*vdev
, VirtQueue
*vq
)
483 static uint32_t get_features(VirtIODevice
*vdev
, uint32_t features
)
487 vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
489 if (vser
->bus
.max_nr_ports
> 1) {
490 features
|= (1 << VIRTIO_CONSOLE_F_MULTIPORT
);
495 /* Guest requested config info */
496 static void get_config(VirtIODevice
*vdev
, uint8_t *config_data
)
500 vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
501 memcpy(config_data
, &vser
->config
, sizeof(struct virtio_console_config
));
504 static void set_config(VirtIODevice
*vdev
, const uint8_t *config_data
)
506 struct virtio_console_config config
;
508 memcpy(&config
, config_data
, sizeof(config
));
511 static void virtio_serial_save(QEMUFile
*f
, void *opaque
)
513 VirtIOSerial
*s
= opaque
;
514 VirtIOSerialPort
*port
;
515 uint32_t nr_active_ports
;
516 unsigned int i
, max_nr_ports
;
518 /* The virtio device */
519 virtio_save(&s
->vdev
, f
);
521 /* The config space */
522 qemu_put_be16s(f
, &s
->config
.cols
);
523 qemu_put_be16s(f
, &s
->config
.rows
);
525 qemu_put_be32s(f
, &s
->config
.max_nr_ports
);
528 max_nr_ports
= tswap32(s
->config
.max_nr_ports
);
529 for (i
= 0; i
< (max_nr_ports
+ 31) / 32; i
++) {
530 qemu_put_be32s(f
, &s
->ports_map
[i
]);
536 QTAILQ_FOREACH(port
, &s
->ports
, next
) {
540 qemu_put_be32s(f
, &nr_active_ports
);
543 * Items in struct VirtIOSerialPort.
545 QTAILQ_FOREACH(port
, &s
->ports
, next
) {
546 uint32_t elem_popped
;
548 qemu_put_be32s(f
, &port
->id
);
549 qemu_put_byte(f
, port
->guest_connected
);
550 qemu_put_byte(f
, port
->host_connected
);
553 if (port
->elem
.out_num
) {
556 qemu_put_be32s(f
, &elem_popped
);
558 qemu_put_be32s(f
, &port
->iov_idx
);
559 qemu_put_be64s(f
, &port
->iov_offset
);
561 qemu_put_buffer(f
, (unsigned char *)&port
->elem
,
567 static int virtio_serial_load(QEMUFile
*f
, void *opaque
, int version_id
)
569 VirtIOSerial
*s
= opaque
;
570 VirtIOSerialPort
*port
;
571 uint32_t max_nr_ports
, nr_active_ports
, ports_map
;
574 if (version_id
> 3) {
578 /* The virtio device */
579 virtio_load(&s
->vdev
, f
);
581 if (version_id
< 2) {
585 /* The config space */
586 qemu_get_be16s(f
, &s
->config
.cols
);
587 qemu_get_be16s(f
, &s
->config
.rows
);
589 qemu_get_be32s(f
, &max_nr_ports
);
590 tswap32s(&max_nr_ports
);
591 if (max_nr_ports
> tswap32(s
->config
.max_nr_ports
)) {
592 /* Source could have had more ports than us. Fail migration. */
596 for (i
= 0; i
< (max_nr_ports
+ 31) / 32; i
++) {
597 qemu_get_be32s(f
, &ports_map
);
599 if (ports_map
!= s
->ports_map
[i
]) {
601 * Ports active on source and destination don't
602 * match. Fail migration.
608 qemu_get_be32s(f
, &nr_active_ports
);
610 /* Items in struct VirtIOSerialPort */
611 for (i
= 0; i
< nr_active_ports
; i
++) {
615 id
= qemu_get_be32(f
);
616 port
= find_port_by_id(s
, id
);
621 port
->guest_connected
= qemu_get_byte(f
);
622 host_connected
= qemu_get_byte(f
);
623 if (host_connected
!= port
->host_connected
) {
625 * We have to let the guest know of the host connection
628 send_control_event(port
, VIRTIO_CONSOLE_PORT_OPEN
,
629 port
->host_connected
);
632 if (version_id
> 2) {
633 uint32_t elem_popped
;
635 qemu_get_be32s(f
, &elem_popped
);
637 qemu_get_be32s(f
, &port
->iov_idx
);
638 qemu_get_be64s(f
, &port
->iov_offset
);
640 qemu_get_buffer(f
, (unsigned char *)&port
->elem
,
642 virtqueue_map_sg(port
->elem
.in_sg
, port
->elem
.in_addr
,
643 port
->elem
.in_num
, 1);
644 virtqueue_map_sg(port
->elem
.out_sg
, port
->elem
.out_addr
,
645 port
->elem
.out_num
, 1);
648 * Port was throttled on source machine. Let's
649 * unthrottle it here so data starts flowing again.
651 virtio_serial_throttle_port(port
, false);
658 static void virtser_bus_dev_print(Monitor
*mon
, DeviceState
*qdev
, int indent
);
660 static struct BusInfo virtser_bus_info
= {
661 .name
= "virtio-serial-bus",
662 .size
= sizeof(VirtIOSerialBus
),
663 .print_dev
= virtser_bus_dev_print
,
666 static void virtser_bus_dev_print(Monitor
*mon
, DeviceState
*qdev
, int indent
)
668 VirtIOSerialPort
*port
= DO_UPCAST(VirtIOSerialPort
, dev
, qdev
);
670 monitor_printf(mon
, "%*s dev-prop-int: id: %u\n",
671 indent
, "", port
->id
);
672 monitor_printf(mon
, "%*s dev-prop-int: guest_connected: %d\n",
673 indent
, "", port
->guest_connected
);
674 monitor_printf(mon
, "%*s dev-prop-int: host_connected: %d\n",
675 indent
, "", port
->host_connected
);
676 monitor_printf(mon
, "%*s dev-prop-int: throttled: %d\n",
677 indent
, "", port
->throttled
);
680 /* This function is only used if a port id is not provided by the user */
681 static uint32_t find_free_port_id(VirtIOSerial
*vser
)
683 unsigned int i
, max_nr_ports
;
685 max_nr_ports
= tswap32(vser
->config
.max_nr_ports
);
686 for (i
= 0; i
< (max_nr_ports
+ 31) / 32; i
++) {
689 map
= vser
->ports_map
[i
];
692 return (bit
- 1) + i
* 32;
695 return VIRTIO_CONSOLE_BAD_ID
;
698 static void mark_port_added(VirtIOSerial
*vser
, uint32_t port_id
)
703 vser
->ports_map
[i
] |= 1U << (port_id
% 32);
706 static void add_port(VirtIOSerial
*vser
, uint32_t port_id
)
708 mark_port_added(vser
, port_id
);
710 send_control_event(find_port_by_id(vser
, port_id
),
711 VIRTIO_CONSOLE_PORT_ADD
, 1);
714 static void remove_port(VirtIOSerial
*vser
, uint32_t port_id
)
716 VirtIOSerialPort
*port
;
720 vser
->ports_map
[i
] &= ~(1U << (port_id
% 32));
722 port
= find_port_by_id(vser
, port_id
);
723 /* Flush out any unconsumed buffers first */
724 discard_vq_data(port
->ovq
, &port
->vser
->vdev
);
726 send_control_event(port
, VIRTIO_CONSOLE_PORT_REMOVE
, 1);
729 static int virtser_port_qdev_init(DeviceState
*qdev
, DeviceInfo
*base
)
731 VirtIOSerialPort
*port
= DO_UPCAST(VirtIOSerialPort
, dev
, qdev
);
732 VirtIOSerialPortInfo
*info
= DO_UPCAST(VirtIOSerialPortInfo
, qdev
, base
);
733 VirtIOSerialBus
*bus
= DO_UPCAST(VirtIOSerialBus
, qbus
, qdev
->parent_bus
);
734 int ret
, max_nr_ports
;
737 port
->vser
= bus
->vser
;
738 port
->bh
= qemu_bh_new(flush_queued_data_bh
, port
);
741 * Is the first console port we're seeing? If so, put it up at
742 * location 0. This is done for backward compatibility (old
745 plugging_port0
= info
->is_console
&& !find_port_by_id(port
->vser
, 0);
747 if (find_port_by_id(port
->vser
, port
->id
)) {
748 error_report("virtio-serial-bus: A port already exists at id %u",
753 if (port
->id
== VIRTIO_CONSOLE_BAD_ID
) {
754 if (plugging_port0
) {
757 port
->id
= find_free_port_id(port
->vser
);
758 if (port
->id
== VIRTIO_CONSOLE_BAD_ID
) {
759 error_report("virtio-serial-bus: Maximum port limit for this device reached");
765 max_nr_ports
= tswap32(port
->vser
->config
.max_nr_ports
);
766 if (port
->id
>= max_nr_ports
) {
767 error_report("virtio-serial-bus: Out-of-range port id specified, max. allowed: %u",
772 ret
= info
->init(port
);
777 if (!use_multiport(port
->vser
)) {
779 * Allow writes to guest in this case; we have no way of
780 * knowing if a guest port is connected.
782 port
->guest_connected
= true;
785 port
->elem
.out_num
= 0;
787 QTAILQ_INSERT_TAIL(&port
->vser
->ports
, port
, next
);
788 port
->ivq
= port
->vser
->ivqs
[port
->id
];
789 port
->ovq
= port
->vser
->ovqs
[port
->id
];
791 add_port(port
->vser
, port
->id
);
793 /* Send an update to the guest about this new port added */
794 virtio_notify_config(&port
->vser
->vdev
);
799 static int virtser_port_qdev_exit(DeviceState
*qdev
)
801 VirtIOSerialPort
*port
= DO_UPCAST(VirtIOSerialPort
, dev
, qdev
);
802 VirtIOSerialPortInfo
*info
= DO_UPCAST(VirtIOSerialPortInfo
, qdev
,
804 VirtIOSerial
*vser
= port
->vser
;
806 qemu_bh_delete(port
->bh
);
807 remove_port(port
->vser
, port
->id
);
809 QTAILQ_REMOVE(&vser
->ports
, port
, next
);
817 void virtio_serial_port_qdev_register(VirtIOSerialPortInfo
*info
)
819 info
->qdev
.init
= virtser_port_qdev_init
;
820 info
->qdev
.bus_info
= &virtser_bus_info
;
821 info
->qdev
.exit
= virtser_port_qdev_exit
;
822 info
->qdev
.unplug
= qdev_simple_unplug_cb
;
823 qdev_register(&info
->qdev
);
826 VirtIODevice
*virtio_serial_init(DeviceState
*dev
, virtio_serial_conf
*conf
)
830 uint32_t i
, max_supported_ports
;
832 if (!conf
->max_virtserial_ports
)
835 /* Each port takes 2 queues, and one pair is for the control queue */
836 max_supported_ports
= VIRTIO_PCI_QUEUE_MAX
/ 2 - 1;
838 if (conf
->max_virtserial_ports
> max_supported_ports
) {
839 error_report("maximum ports supported: %u", max_supported_ports
);
843 vdev
= virtio_common_init("virtio-serial", VIRTIO_ID_CONSOLE
,
844 sizeof(struct virtio_console_config
),
845 sizeof(VirtIOSerial
));
847 vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
849 /* Spawn a new virtio-serial bus on which the ports will ride as devices */
850 qbus_create_inplace(&vser
->bus
.qbus
, &virtser_bus_info
, dev
, NULL
);
851 vser
->bus
.qbus
.allow_hotplug
= 1;
852 vser
->bus
.vser
= vser
;
853 QTAILQ_INIT(&vser
->ports
);
855 vser
->bus
.max_nr_ports
= conf
->max_virtserial_ports
;
856 vser
->ivqs
= qemu_malloc(conf
->max_virtserial_ports
* sizeof(VirtQueue
*));
857 vser
->ovqs
= qemu_malloc(conf
->max_virtserial_ports
* sizeof(VirtQueue
*));
859 /* Add a queue for host to guest transfers for port 0 (backward compat) */
860 vser
->ivqs
[0] = virtio_add_queue(vdev
, 128, handle_input
);
861 /* Add a queue for guest to host transfers for port 0 (backward compat) */
862 vser
->ovqs
[0] = virtio_add_queue(vdev
, 128, handle_output
);
864 /* TODO: host to guest notifications can get dropped
865 * if the queue fills up. Implement queueing in host,
866 * this might also make it possible to reduce the control
867 * queue size: as guest preposts buffers there,
868 * this will save 4Kbyte of guest memory per entry. */
870 /* control queue: host to guest */
871 vser
->c_ivq
= virtio_add_queue(vdev
, 32, control_in
);
872 /* control queue: guest to host */
873 vser
->c_ovq
= virtio_add_queue(vdev
, 32, control_out
);
875 for (i
= 1; i
< vser
->bus
.max_nr_ports
; i
++) {
876 /* Add a per-port queue for host to guest transfers */
877 vser
->ivqs
[i
] = virtio_add_queue(vdev
, 128, handle_input
);
878 /* Add a per-per queue for guest to host transfers */
879 vser
->ovqs
[i
] = virtio_add_queue(vdev
, 128, handle_output
);
882 vser
->config
.max_nr_ports
= tswap32(conf
->max_virtserial_ports
);
883 vser
->ports_map
= qemu_mallocz(((conf
->max_virtserial_ports
+ 31) / 32)
884 * sizeof(vser
->ports_map
[0]));
886 * Reserve location 0 for a console port for backward compat
887 * (old kernel, new qemu)
889 mark_port_added(vser
, 0);
891 vser
->vdev
.get_features
= get_features
;
892 vser
->vdev
.get_config
= get_config
;
893 vser
->vdev
.set_config
= set_config
;
898 * Register for the savevm section with the virtio-console name
899 * to preserve backward compat
901 register_savevm(dev
, "virtio-console", -1, 3, virtio_serial_save
,
902 virtio_serial_load
, vser
);
907 void virtio_serial_exit(VirtIODevice
*vdev
)
909 VirtIOSerial
*vser
= DO_UPCAST(VirtIOSerial
, vdev
, vdev
);
911 unregister_savevm(vser
->qdev
, "virtio-console", vser
);
913 qemu_free(vser
->ivqs
);
914 qemu_free(vser
->ovqs
);
915 qemu_free(vser
->ports_map
);
917 virtio_cleanup(vdev
);