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qemu/hw/virtio-serial-bus.c

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/*
* A bus for connecting virtio serial and console ports
*
* Copyright (C) 2009, 2010 Red Hat, Inc.
*
* Author(s):
* Amit Shah <amit.shah@redhat.com>
*
* Some earlier parts are:
* Copyright IBM, Corp. 2008
* authored by
* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "iov.h"
#include "monitor.h"
#include "qemu-queue.h"
#include "sysbus.h"
#include "trace.h"
#include "virtio-serial.h"
/* The virtio-serial bus on top of which the ports will ride as devices */
struct VirtIOSerialBus {
BusState qbus;
/* This is the parent device that provides the bus for ports. */
VirtIOSerial *vser;
/* The maximum number of ports that can ride on top of this bus */
uint32_t max_nr_ports;
};
struct VirtIOSerial {
VirtIODevice vdev;
VirtQueue *c_ivq, *c_ovq;
/* Arrays of ivqs and ovqs: one per port */
VirtQueue **ivqs, **ovqs;
VirtIOSerialBus bus;
DeviceState *qdev;
QTAILQ_HEAD(, VirtIOSerialPort) ports;
/* bitmap for identifying active ports */
uint32_t *ports_map;
struct virtio_console_config config;
};
static VirtIOSerialPort *find_port_by_id(VirtIOSerial *vser, uint32_t id)
{
VirtIOSerialPort *port;
if (id == VIRTIO_CONSOLE_BAD_ID) {
return NULL;
}
QTAILQ_FOREACH(port, &vser->ports, next) {
if (port->id == id)
return port;
}
return NULL;
}
static VirtIOSerialPort *find_port_by_vq(VirtIOSerial *vser, VirtQueue *vq)
{
VirtIOSerialPort *port;
QTAILQ_FOREACH(port, &vser->ports, next) {
if (port->ivq == vq || port->ovq == vq)
return port;
}
return NULL;
}
static bool use_multiport(VirtIOSerial *vser)
{
return vser->vdev.guest_features & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
}
static size_t write_to_port(VirtIOSerialPort *port,
const uint8_t *buf, size_t size)
{
VirtQueueElement elem;
VirtQueue *vq;
size_t offset;
vq = port->ivq;
if (!virtio_queue_ready(vq)) {
return 0;
}
offset = 0;
while (offset < size) {
size_t len;
if (!virtqueue_pop(vq, &elem)) {
break;
}
len = iov_from_buf(elem.in_sg, elem.in_num, 0,
buf + offset, size - offset);
offset += len;
virtqueue_push(vq, &elem, len);
}
virtio_notify(&port->vser->vdev, vq);
return offset;
}
static void discard_vq_data(VirtQueue *vq, VirtIODevice *vdev)
{
VirtQueueElement elem;
if (!virtio_queue_ready(vq)) {
return;
}
while (virtqueue_pop(vq, &elem)) {
virtqueue_push(vq, &elem, 0);
}
virtio_notify(vdev, vq);
}
static void do_flush_queued_data(VirtIOSerialPort *port, VirtQueue *vq,
VirtIODevice *vdev)
{
VirtIOSerialPortClass *vsc;
assert(port);
assert(virtio_queue_ready(vq));
vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
while (!port->throttled) {
unsigned int i;
/* Pop an elem only if we haven't left off a previous one mid-way */
if (!port->elem.out_num) {
if (!virtqueue_pop(vq, &port->elem)) {
break;
}
port->iov_idx = 0;
port->iov_offset = 0;
}
for (i = port->iov_idx; i < port->elem.out_num; i++) {
size_t buf_size;
ssize_t ret;
buf_size = port->elem.out_sg[i].iov_len - port->iov_offset;
ret = vsc->have_data(port,
port->elem.out_sg[i].iov_base
+ port->iov_offset,
buf_size);
if (ret < 0 && ret != -EAGAIN) {
/* We don't handle any other type of errors here */
abort();
}
if (ret == -EAGAIN || (ret >= 0 && ret < buf_size)) {
/*
* this is a temporary check until chardevs can signal to
* frontends that they are writable again. This prevents
* the console from going into throttled mode (forever)
* if virtio-console is connected to a pty without a
* listener. Otherwise the guest spins forever.
* We can revert this if
* 1: chardevs can notify frondends
* 2: the guest driver does not spin in these cases
*/
if (!vsc->is_console) {
virtio_serial_throttle_port(port, true);
}
port->iov_idx = i;
if (ret > 0) {
port->iov_offset += ret;
}
break;
}
port->iov_offset = 0;
}
if (port->throttled) {
break;
}
virtqueue_push(vq, &port->elem, 0);
port->elem.out_num = 0;
}
virtio_notify(vdev, vq);
}
static void flush_queued_data(VirtIOSerialPort *port)
{
assert(port);
if (!virtio_queue_ready(port->ovq)) {
return;
}
do_flush_queued_data(port, port->ovq, &port->vser->vdev);
}
static size_t send_control_msg(VirtIOSerialPort *port, void *buf, size_t len)
{
VirtQueueElement elem;
VirtQueue *vq;
struct virtio_console_control *cpkt;
vq = port->vser->c_ivq;
if (!virtio_queue_ready(vq)) {
return 0;
}
if (!virtqueue_pop(vq, &elem)) {
return 0;
}
cpkt = (struct virtio_console_control *)buf;
stl_p(&cpkt->id, port->id);
memcpy(elem.in_sg[0].iov_base, buf, len);
virtqueue_push(vq, &elem, len);
virtio_notify(&port->vser->vdev, vq);
return len;
}
static size_t send_control_event(VirtIOSerialPort *port, uint16_t event,
uint16_t value)
{
struct virtio_console_control cpkt;
stw_p(&cpkt.event, event);
stw_p(&cpkt.value, value);
trace_virtio_serial_send_control_event(port->id, event, value);
return send_control_msg(port, &cpkt, sizeof(cpkt));
}
/* Functions for use inside qemu to open and read from/write to ports */
int virtio_serial_open(VirtIOSerialPort *port)
{
/* Don't allow opening an already-open port */
if (port->host_connected) {
return 0;
}
/* Send port open notification to the guest */
port->host_connected = true;
send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
return 0;
}
int virtio_serial_close(VirtIOSerialPort *port)
{
port->host_connected = false;
/*
* If there's any data the guest sent which the app didn't
* consume, reset the throttling flag and discard the data.
*/
port->throttled = false;
discard_vq_data(port->ovq, &port->vser->vdev);
send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
return 0;
}
/* Individual ports/apps call this function to write to the guest. */
ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf,
size_t size)
{
if (!port || !port->host_connected || !port->guest_connected) {
return 0;
}
return write_to_port(port, buf, size);
}
/*
* Readiness of the guest to accept data on a port.
* Returns max. data the guest can receive
*/
size_t virtio_serial_guest_ready(VirtIOSerialPort *port)
{
VirtQueue *vq = port->ivq;
if (!virtio_queue_ready(vq) ||
!(port->vser->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK) ||
virtio_queue_empty(vq)) {
return 0;
}
if (use_multiport(port->vser) && !port->guest_connected) {
return 0;
}
if (virtqueue_avail_bytes(vq, 4096, 0)) {
return 4096;
}
if (virtqueue_avail_bytes(vq, 1, 0)) {
return 1;
}
return 0;
}
static void flush_queued_data_bh(void *opaque)
{
VirtIOSerialPort *port = opaque;
flush_queued_data(port);
}
void virtio_serial_throttle_port(VirtIOSerialPort *port, bool throttle)
{
if (!port) {
return;
}
trace_virtio_serial_throttle_port(port->id, throttle);
port->throttled = throttle;
if (throttle) {
return;
}
qemu_bh_schedule(port->bh);
}
/* Guest wants to notify us of some event */
static void handle_control_message(VirtIOSerial *vser, void *buf, size_t len)
{
struct VirtIOSerialPort *port;
VirtIOSerialPortClass *vsc;
struct virtio_console_control cpkt, *gcpkt;
uint8_t *buffer;
size_t buffer_len;
gcpkt = buf;
if (len < sizeof(cpkt)) {
/* The guest sent an invalid control packet */
return;
}
cpkt.event = lduw_p(&gcpkt->event);
cpkt.value = lduw_p(&gcpkt->value);
trace_virtio_serial_handle_control_message(cpkt.event, cpkt.value);
if (cpkt.event == VIRTIO_CONSOLE_DEVICE_READY) {
if (!cpkt.value) {
error_report("virtio-serial-bus: Guest failure in adding device %s",
vser->bus.qbus.name);
return;
}
/*
* The device is up, we can now tell the device about all the
* ports we have here.
*/
QTAILQ_FOREACH(port, &vser->ports, next) {
send_control_event(port, VIRTIO_CONSOLE_PORT_ADD, 1);
}
return;
}
port = find_port_by_id(vser, ldl_p(&gcpkt->id));
if (!port) {
error_report("virtio-serial-bus: Unexpected port id %u for device %s",
ldl_p(&gcpkt->id), vser->bus.qbus.name);
return;
}
trace_virtio_serial_handle_control_message_port(port->id);
vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
switch(cpkt.event) {
case VIRTIO_CONSOLE_PORT_READY:
if (!cpkt.value) {
error_report("virtio-serial-bus: Guest failure in adding port %u for device %s",
port->id, vser->bus.qbus.name);
break;
}
/*
* Now that we know the guest asked for the port name, we're
* sure the guest has initialised whatever state is necessary
* for this port. Now's a good time to let the guest know if
* this port is a console port so that the guest can hook it
* up to hvc.
*/
if (vsc->is_console) {
send_control_event(port, VIRTIO_CONSOLE_CONSOLE_PORT, 1);
}
if (port->name) {
stw_p(&cpkt.event, VIRTIO_CONSOLE_PORT_NAME);
stw_p(&cpkt.value, 1);
buffer_len = sizeof(cpkt) + strlen(port->name) + 1;
buffer = g_malloc(buffer_len);
memcpy(buffer, &cpkt, sizeof(cpkt));
memcpy(buffer + sizeof(cpkt), port->name, strlen(port->name));
buffer[buffer_len - 1] = 0;
send_control_msg(port, buffer, buffer_len);
g_free(buffer);
}
if (port->host_connected) {
send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
}
/*
* When the guest has asked us for this information it means
* the guest is all setup and has its virtqueues
* initialised. If some app is interested in knowing about
* this event, let it know.
*/
if (vsc->guest_ready) {
vsc->guest_ready(port);
}
break;
case VIRTIO_CONSOLE_PORT_OPEN:
port->guest_connected = cpkt.value;
if (cpkt.value && vsc->guest_open) {
/* Send the guest opened notification if an app is interested */
vsc->guest_open(port);
}
if (!cpkt.value && vsc->guest_close) {
/* Send the guest closed notification if an app is interested */
vsc->guest_close(port);
}
break;
}
}
static void control_in(VirtIODevice *vdev, VirtQueue *vq)
{
}
static void control_out(VirtIODevice *vdev, VirtQueue *vq)
{
VirtQueueElement elem;
VirtIOSerial *vser;
uint8_t *buf;
size_t len;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
len = 0;
buf = NULL;
while (virtqueue_pop(vq, &elem)) {
size_t cur_len;
cur_len = iov_size(elem.out_sg, elem.out_num);
/*
* Allocate a new buf only if we didn't have one previously or
* if the size of the buf differs
*/
if (cur_len > len) {
g_free(buf);
buf = g_malloc(cur_len);
len = cur_len;
}
iov_to_buf(elem.out_sg, elem.out_num, 0, buf, cur_len);
handle_control_message(vser, buf, cur_len);
virtqueue_push(vq, &elem, 0);
}
g_free(buf);
virtio_notify(vdev, vq);
}
/* Guest wrote something to some port. */
static void handle_output(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSerial *vser;
VirtIOSerialPort *port;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
port = find_port_by_vq(vser, vq);
if (!port || !port->host_connected) {
discard_vq_data(vq, vdev);
return;
}
if (!port->throttled) {
do_flush_queued_data(port, vq, vdev);
return;
}
}
static void handle_input(VirtIODevice *vdev, VirtQueue *vq)
{
}
static uint32_t get_features(VirtIODevice *vdev, uint32_t features)
{
VirtIOSerial *vser;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
if (vser->bus.max_nr_ports > 1) {
features |= (1 << VIRTIO_CONSOLE_F_MULTIPORT);
}
return features;
}
/* Guest requested config info */
static void get_config(VirtIODevice *vdev, uint8_t *config_data)
{
VirtIOSerial *vser;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
memcpy(config_data, &vser->config, sizeof(struct virtio_console_config));
}
static void set_config(VirtIODevice *vdev, const uint8_t *config_data)
{
struct virtio_console_config config;
memcpy(&config, config_data, sizeof(config));
}
static void guest_reset(VirtIOSerial *vser)
{
VirtIOSerialPort *port;
VirtIOSerialPortClass *vsc;
QTAILQ_FOREACH(port, &vser->ports, next) {
vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
if (port->guest_connected) {
port->guest_connected = false;
if (vsc->guest_close)
vsc->guest_close(port);
}
}
}
static void set_status(VirtIODevice *vdev, uint8_t status)
{
VirtIOSerial *vser;
VirtIOSerialPort *port;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
port = find_port_by_id(vser, 0);
if (port && !use_multiport(port->vser)
&& (status & VIRTIO_CONFIG_S_DRIVER_OK)) {
/*
* Non-multiport guests won't be able to tell us guest
* open/close status. Such guests can only have a port at id
* 0, so set guest_connected for such ports as soon as guest
* is up.
*/
port->guest_connected = true;
}
if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
guest_reset(vser);
}
}
static void vser_reset(VirtIODevice *vdev)
{
VirtIOSerial *vser;
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
guest_reset(vser);
}
static void virtio_serial_save(QEMUFile *f, void *opaque)
{
VirtIOSerial *s = opaque;
VirtIOSerialPort *port;
uint32_t nr_active_ports;
unsigned int i, max_nr_ports;
/* The virtio device */
virtio_save(&s->vdev, f);
/* The config space */
qemu_put_be16s(f, &s->config.cols);
qemu_put_be16s(f, &s->config.rows);
qemu_put_be32s(f, &s->config.max_nr_ports);
/* The ports map */
max_nr_ports = tswap32(s->config.max_nr_ports);
for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
qemu_put_be32s(f, &s->ports_map[i]);
}
/* Ports */
nr_active_ports = 0;
QTAILQ_FOREACH(port, &s->ports, next) {
nr_active_ports++;
}
qemu_put_be32s(f, &nr_active_ports);
/*
* Items in struct VirtIOSerialPort.
*/
QTAILQ_FOREACH(port, &s->ports, next) {
uint32_t elem_popped;
qemu_put_be32s(f, &port->id);
qemu_put_byte(f, port->guest_connected);
qemu_put_byte(f, port->host_connected);
elem_popped = 0;
if (port->elem.out_num) {
elem_popped = 1;
}
qemu_put_be32s(f, &elem_popped);
if (elem_popped) {
qemu_put_be32s(f, &port->iov_idx);
qemu_put_be64s(f, &port->iov_offset);
qemu_put_buffer(f, (unsigned char *)&port->elem,
sizeof(port->elem));
}
}
}
static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIOSerial *s = opaque;
VirtIOSerialPort *port;
uint32_t max_nr_ports, nr_active_ports, ports_map;
unsigned int i;
int ret;
if (version_id > 3) {
return -EINVAL;
}
/* The virtio device */
ret = virtio_load(&s->vdev, f);
if (ret) {
return ret;
}
if (version_id < 2) {
return 0;
}
/* The config space */
qemu_get_be16s(f, &s->config.cols);
qemu_get_be16s(f, &s->config.rows);
qemu_get_be32s(f, &max_nr_ports);
tswap32s(&max_nr_ports);
if (max_nr_ports > tswap32(s->config.max_nr_ports)) {
/* Source could have had more ports than us. Fail migration. */
return -EINVAL;
}
for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
qemu_get_be32s(f, &ports_map);
if (ports_map != s->ports_map[i]) {
/*
* Ports active on source and destination don't
* match. Fail migration.
*/
return -EINVAL;
}
}
qemu_get_be32s(f, &nr_active_ports);
/* Items in struct VirtIOSerialPort */
for (i = 0; i < nr_active_ports; i++) {
uint32_t id;
bool host_connected;
id = qemu_get_be32(f);
port = find_port_by_id(s, id);
if (!port) {
return -EINVAL;
}
port->guest_connected = qemu_get_byte(f);
host_connected = qemu_get_byte(f);
if (host_connected != port->host_connected) {
/*
* We have to let the guest know of the host connection
* status change
*/
send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN,
port->host_connected);
}
if (version_id > 2) {
uint32_t elem_popped;
qemu_get_be32s(f, &elem_popped);
if (elem_popped) {
qemu_get_be32s(f, &port->iov_idx);
qemu_get_be64s(f, &port->iov_offset);
qemu_get_buffer(f, (unsigned char *)&port->elem,
sizeof(port->elem));
virtqueue_map_sg(port->elem.in_sg, port->elem.in_addr,
port->elem.in_num, 1);
virtqueue_map_sg(port->elem.out_sg, port->elem.out_addr,
port->elem.out_num, 1);
/*
* Port was throttled on source machine. Let's
* unthrottle it here so data starts flowing again.
*/
virtio_serial_throttle_port(port, false);
}
}
}
return 0;
}
static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent);
static Property virtser_props[] = {
DEFINE_PROP_UINT32("nr", VirtIOSerialPort, id, VIRTIO_CONSOLE_BAD_ID),
DEFINE_PROP_STRING("name", VirtIOSerialPort, name),
DEFINE_PROP_END_OF_LIST()
};
#define TYPE_VIRTIO_SERIAL_BUS "virtio-serial-bus"
#define VIRTIO_SERIAL_BUS(obj) \
OBJECT_CHECK(VirtIOSerialBus, (obj), TYPE_VIRTIO_SERIAL_BUS)
static void virtser_bus_class_init(ObjectClass *klass, void *data)
{
BusClass *k = BUS_CLASS(klass);
k->print_dev = virtser_bus_dev_print;
}
static const TypeInfo virtser_bus_info = {
.name = TYPE_VIRTIO_SERIAL_BUS,
.parent = TYPE_BUS,
.instance_size = sizeof(VirtIOSerialBus),
.class_init = virtser_bus_class_init,
};
static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent)
{
VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev);
monitor_printf(mon, "%*sport %d, guest %s, host %s, throttle %s\n",
indent, "", port->id,
port->guest_connected ? "on" : "off",
port->host_connected ? "on" : "off",
port->throttled ? "on" : "off");
}
/* This function is only used if a port id is not provided by the user */
static uint32_t find_free_port_id(VirtIOSerial *vser)
{
unsigned int i, max_nr_ports;
max_nr_ports = tswap32(vser->config.max_nr_ports);
for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
uint32_t map, bit;
map = vser->ports_map[i];
bit = ffs(~map);
if (bit) {
return (bit - 1) + i * 32;
}
}
return VIRTIO_CONSOLE_BAD_ID;
}
static void mark_port_added(VirtIOSerial *vser, uint32_t port_id)
{
unsigned int i;
i = port_id / 32;
vser->ports_map[i] |= 1U << (port_id % 32);
}
static void add_port(VirtIOSerial *vser, uint32_t port_id)
{
mark_port_added(vser, port_id);
send_control_event(find_port_by_id(vser, port_id),
VIRTIO_CONSOLE_PORT_ADD, 1);
}
static void remove_port(VirtIOSerial *vser, uint32_t port_id)
{
VirtIOSerialPort *port;
unsigned int i;
i = port_id / 32;
vser->ports_map[i] &= ~(1U << (port_id % 32));
port = find_port_by_id(vser, port_id);
/* Flush out any unconsumed buffers first */
discard_vq_data(port->ovq, &port->vser->vdev);
send_control_event(port, VIRTIO_CONSOLE_PORT_REMOVE, 1);
}
static int virtser_port_qdev_init(DeviceState *qdev)
{
VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev);
VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
VirtIOSerialBus *bus = DO_UPCAST(VirtIOSerialBus, qbus, qdev->parent_bus);
int ret, max_nr_ports;
bool plugging_port0;
port->vser = bus->vser;
port->bh = qemu_bh_new(flush_queued_data_bh, port);
assert(vsc->have_data);
/*
* Is the first console port we're seeing? If so, put it up at
* location 0. This is done for backward compatibility (old
* kernel, new qemu).
*/
plugging_port0 = vsc->is_console && !find_port_by_id(port->vser, 0);
if (find_port_by_id(port->vser, port->id)) {
error_report("virtio-serial-bus: A port already exists at id %u",
port->id);
return -1;
}
if (port->id == VIRTIO_CONSOLE_BAD_ID) {
if (plugging_port0) {
port->id = 0;
} else {
port->id = find_free_port_id(port->vser);
if (port->id == VIRTIO_CONSOLE_BAD_ID) {
error_report("virtio-serial-bus: Maximum port limit for this device reached");
return -1;
}
}
}
max_nr_ports = tswap32(port->vser->config.max_nr_ports);
if (port->id >= max_nr_ports) {
error_report("virtio-serial-bus: Out-of-range port id specified, max. allowed: %u",
max_nr_ports - 1);
return -1;
}
ret = vsc->init(port);
if (ret) {
return ret;
}
port->elem.out_num = 0;
QTAILQ_INSERT_TAIL(&port->vser->ports, port, next);
port->ivq = port->vser->ivqs[port->id];
port->ovq = port->vser->ovqs[port->id];
add_port(port->vser, port->id);
/* Send an update to the guest about this new port added */
virtio_notify_config(&port->vser->vdev);
return ret;
}
static int virtser_port_qdev_exit(DeviceState *qdev)
{
VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev);
VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
VirtIOSerial *vser = port->vser;
qemu_bh_delete(port->bh);
remove_port(port->vser, port->id);
QTAILQ_REMOVE(&vser->ports, port, next);
if (vsc->exit) {
vsc->exit(port);
}
return 0;
}
VirtIODevice *virtio_serial_init(DeviceState *dev, virtio_serial_conf *conf)
{
VirtIOSerial *vser;
VirtIODevice *vdev;
uint32_t i, max_supported_ports;
if (!conf->max_virtserial_ports)
return NULL;
/* Each port takes 2 queues, and one pair is for the control queue */
max_supported_ports = VIRTIO_PCI_QUEUE_MAX / 2 - 1;
if (conf->max_virtserial_ports > max_supported_ports) {
error_report("maximum ports supported: %u", max_supported_ports);
return NULL;
}
vdev = virtio_common_init("virtio-serial", VIRTIO_ID_CONSOLE,
sizeof(struct virtio_console_config),
sizeof(VirtIOSerial));
vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
/* Spawn a new virtio-serial bus on which the ports will ride as devices */
qbus_create_inplace(&vser->bus.qbus, TYPE_VIRTIO_SERIAL_BUS, dev, NULL);
vser->bus.qbus.allow_hotplug = 1;
vser->bus.vser = vser;
QTAILQ_INIT(&vser->ports);
vser->bus.max_nr_ports = conf->max_virtserial_ports;
vser->ivqs = g_malloc(conf->max_virtserial_ports * sizeof(VirtQueue *));
vser->ovqs = g_malloc(conf->max_virtserial_ports * sizeof(VirtQueue *));
/* Add a queue for host to guest transfers for port 0 (backward compat) */
vser->ivqs[0] = virtio_add_queue(vdev, 128, handle_input);
/* Add a queue for guest to host transfers for port 0 (backward compat) */
vser->ovqs[0] = virtio_add_queue(vdev, 128, handle_output);
/* TODO: host to guest notifications can get dropped
* if the queue fills up. Implement queueing in host,
* this might also make it possible to reduce the control
* queue size: as guest preposts buffers there,
* this will save 4Kbyte of guest memory per entry. */
/* control queue: host to guest */
vser->c_ivq = virtio_add_queue(vdev, 32, control_in);
/* control queue: guest to host */
vser->c_ovq = virtio_add_queue(vdev, 32, control_out);
for (i = 1; i < vser->bus.max_nr_ports; i++) {
/* Add a per-port queue for host to guest transfers */
vser->ivqs[i] = virtio_add_queue(vdev, 128, handle_input);
/* Add a per-per queue for guest to host transfers */
vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output);
}
vser->config.max_nr_ports = tswap32(conf->max_virtserial_ports);
vser->ports_map = g_malloc0(((conf->max_virtserial_ports + 31) / 32)
* sizeof(vser->ports_map[0]));
/*
* Reserve location 0 for a console port for backward compat
* (old kernel, new qemu)
*/
mark_port_added(vser, 0);
vser->vdev.get_features = get_features;
vser->vdev.get_config = get_config;
vser->vdev.set_config = set_config;
vser->vdev.set_status = set_status;
vser->vdev.reset = vser_reset;
vser->qdev = dev;
/*
* Register for the savevm section with the virtio-console name
* to preserve backward compat
*/
register_savevm(dev, "virtio-console", -1, 3, virtio_serial_save,
virtio_serial_load, vser);
return vdev;
}
void virtio_serial_exit(VirtIODevice *vdev)
{
VirtIOSerial *vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
unregister_savevm(vser->qdev, "virtio-console", vser);
g_free(vser->ivqs);
g_free(vser->ovqs);
g_free(vser->ports_map);
virtio_cleanup(vdev);
}
static void virtio_serial_port_class_init(ObjectClass *klass, void *data)
{
DeviceClass *k = DEVICE_CLASS(klass);
k->init = virtser_port_qdev_init;
k->bus_type = TYPE_VIRTIO_SERIAL_BUS;
k->exit = virtser_port_qdev_exit;
k->unplug = qdev_simple_unplug_cb;
k->props = virtser_props;
}
static TypeInfo virtio_serial_port_type_info = {
.name = TYPE_VIRTIO_SERIAL_PORT,
.parent = TYPE_DEVICE,
.instance_size = sizeof(VirtIOSerialPort),
.abstract = true,
.class_size = sizeof(VirtIOSerialPortClass),
.class_init = virtio_serial_port_class_init,
};
static void virtio_serial_register_types(void)
{
type_register_static(&virtser_bus_info);
type_register_static(&virtio_serial_port_type_info);
}
type_init(virtio_serial_register_types)
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