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qemu-patch-raspberry4/hw/virtio-serial-bus.c
Michael Tokarev dcf6f5e15e change iov_* function prototypes to be more appropriate 
Reorder arguments to be more natural, readable and
consistent with other iov_* functions, and change
argument names, from:
 iov_from_buf(iov, iov_cnt, buf, iov_off, size)
to
 iov_from_buf(iov, iov_cnt, offset, buf, bytes)

The result becomes natural English:

 copy data to this `iov' vector with `iov_cnt'
 elements starting at byte offset `offset'
 from memory buffer `buf', processing `bytes'
 bytes max.

(Try to read the original prototype this way).

Also change iov_clear() to more general iov_memset()
(it uses memset() internally anyway).

While at it, add comments to the header file
describing what the routines actually does.

The patch only renames argumens in the header, but
keeps old names in the implementation.  The next
patch will touch actual code to match.

Now, it might look wrong to pay so much attention
to so small things.  But we've so many badly designed
interfaces already so the whole thing becomes rather
confusing or error prone.  One example of this is
previous commit and small discussion which emerged
from it, with an outcome that the utility functions
like these aren't well-understdandable, leading to
strange usage cases.  That's why I paid quite some
attention to this set of functions and a few
others in subsequent patches.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2012-06-07 20:43:38 +04:00

1003 lines
27 KiB
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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 struct BusInfo virtser_bus_info = {
.name = "virtio-serial-bus",
.size = sizeof(VirtIOSerialBus),
.print_dev = virtser_bus_dev_print,
.props = (Property[]) {
DEFINE_PROP_UINT32("nr", VirtIOSerialPort, id, VIRTIO_CONSOLE_BAD_ID),
DEFINE_PROP_STRING("name", VirtIOSerialPort, name),
DEFINE_PROP_END_OF_LIST()
}
};
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, &virtser_bus_info, 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_info = &virtser_bus_info;
k->exit = virtser_port_qdev_exit;
k->unplug = qdev_simple_unplug_cb;
}
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(&virtio_serial_port_type_info);
}
type_init(virtio_serial_register_types)
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