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-rw-r--r--qemu/hw/char/virtio-serial-bus.c1134
1 files changed, 1134 insertions, 0 deletions
diff --git a/qemu/hw/char/virtio-serial-bus.c b/qemu/hw/char/virtio-serial-bus.c
new file mode 100644
index 000000000..bc56f5d52
--- /dev/null
+++ b/qemu/hw/char/virtio-serial-bus.c
@@ -0,0 +1,1134 @@
+/*
+ * 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 "qemu/iov.h"
+#include "monitor/monitor.h"
+#include "qemu/error-report.h"
+#include "qemu/queue.h"
+#include "hw/sysbus.h"
+#include "trace.h"
+#include "hw/virtio/virtio-serial.h"
+#include "hw/virtio/virtio-access.h"
+
+static struct VirtIOSerialDevices {
+ QLIST_HEAD(, VirtIOSerial) devices;
+} vserdevices;
+
+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 VirtIOSerialPort *find_port_by_name(char *name)
+{
+ VirtIOSerial *vser;
+
+ QLIST_FOREACH(vser, &vserdevices.devices, next) {
+ VirtIOSerialPort *port;
+
+ QTAILQ_FOREACH(port, &vser->ports, next) {
+ if (port->name && !strcmp(port->name, name)) {
+ return port;
+ }
+ }
+ }
+ return NULL;
+}
+
+static bool use_multiport(VirtIOSerial *vser)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(vser);
+ return virtio_has_feature(vdev, 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(VIRTIO_DEVICE(port->vser), 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 (port->throttled) {
+ 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, VIRTIO_DEVICE(port->vser));
+}
+
+static size_t send_control_msg(VirtIOSerial *vser, void *buf, size_t len)
+{
+ VirtQueueElement elem;
+ VirtQueue *vq;
+
+ vq = vser->c_ivq;
+ if (!virtio_queue_ready(vq)) {
+ return 0;
+ }
+ if (!virtqueue_pop(vq, &elem)) {
+ return 0;
+ }
+
+ /* TODO: detect a buffer that's too short, set NEEDS_RESET */
+ iov_from_buf(elem.in_sg, elem.in_num, 0, buf, len);
+
+ virtqueue_push(vq, &elem, len);
+ virtio_notify(VIRTIO_DEVICE(vser), vq);
+ return len;
+}
+
+static size_t send_control_event(VirtIOSerial *vser, uint32_t port_id,
+ uint16_t event, uint16_t value)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(vser);
+ struct virtio_console_control cpkt;
+
+ virtio_stl_p(vdev, &cpkt.id, port_id);
+ virtio_stw_p(vdev, &cpkt.event, event);
+ virtio_stw_p(vdev, &cpkt.value, value);
+
+ trace_virtio_serial_send_control_event(port_id, event, value);
+ return send_control_msg(vser, &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->vser, port->id, 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, VIRTIO_DEVICE(port->vser));
+
+ send_control_event(port->vser, port->id, 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)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(port->vser);
+ VirtQueue *vq = port->ivq;
+ unsigned int bytes;
+
+ if (!virtio_queue_ready(vq) ||
+ !(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) ||
+ virtio_queue_empty(vq)) {
+ return 0;
+ }
+ if (use_multiport(port->vser) && !port->guest_connected) {
+ return 0;
+ }
+ virtqueue_get_avail_bytes(vq, &bytes, NULL, 4096, 0);
+ return bytes;
+}
+
+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)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(vser);
+ 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 = virtio_lduw_p(vdev, &gcpkt->event);
+ cpkt.value = virtio_lduw_p(vdev, &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(vser, port->id, VIRTIO_CONSOLE_PORT_ADD, 1);
+ }
+ return;
+ }
+
+ port = find_port_by_id(vser, virtio_ldl_p(vdev, &gcpkt->id));
+ if (!port) {
+ error_report("virtio-serial-bus: Unexpected port id %u for device %s",
+ virtio_ldl_p(vdev, &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(vser, port->id, VIRTIO_CONSOLE_CONSOLE_PORT, 1);
+ }
+
+ if (port->name) {
+ virtio_stl_p(vdev, &cpkt.id, port->id);
+ virtio_stw_p(vdev, &cpkt.event, VIRTIO_CONSOLE_PORT_NAME);
+ virtio_stw_p(vdev, &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(vser, buffer, buffer_len);
+ g_free(buffer);
+ }
+
+ if (port->host_connected) {
+ send_control_event(vser, port->id, 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 (vsc->set_guest_connected) {
+ /* Send the guest opened notification if an app is interested */
+ vsc->set_guest_connected(port, cpkt.value);
+ }
+ 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 = VIRTIO_SERIAL(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 = VIRTIO_SERIAL(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)
+{
+ /*
+ * Users of virtio-serial would like to know when guest becomes
+ * writable again -- i.e. if a vq had stuff queued up and the
+ * guest wasn't reading at all, the host would not be able to
+ * write to the vq anymore. Once the guest reads off something,
+ * we can start queueing things up again. However, this call is
+ * made for each buffer addition by the guest -- even though free
+ * buffers existed prior to the current buffer addition. This is
+ * done so as not to maintain previous state, which will need
+ * additional live-migration-related changes.
+ */
+ VirtIOSerial *vser;
+ VirtIOSerialPort *port;
+ VirtIOSerialPortClass *vsc;
+
+ vser = VIRTIO_SERIAL(vdev);
+ port = find_port_by_vq(vser, vq);
+
+ if (!port) {
+ return;
+ }
+ vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
+
+ /*
+ * If guest_connected is false, this call is being made by the
+ * early-boot queueing up of descriptors, which is just noise for
+ * the host apps -- don't disturb them in that case.
+ */
+ if (port->guest_connected && port->host_connected && vsc->guest_writable) {
+ vsc->guest_writable(port);
+ }
+}
+
+static uint64_t get_features(VirtIODevice *vdev, uint64_t features,
+ Error **errp)
+{
+ VirtIOSerial *vser;
+
+ vser = VIRTIO_SERIAL(vdev);
+
+ if (vser->bus.max_nr_ports > 1) {
+ virtio_add_feature(&features, VIRTIO_CONSOLE_F_MULTIPORT);
+ }
+ return features;
+}
+
+/* Guest requested config info */
+static void get_config(VirtIODevice *vdev, uint8_t *config_data)
+{
+ VirtIOSerial *vser = VIRTIO_SERIAL(vdev);
+ struct virtio_console_config *config =
+ (struct virtio_console_config *)config_data;
+
+ config->cols = 0;
+ config->rows = 0;
+ config->max_nr_ports = virtio_tswap32(vdev,
+ vser->serial.max_virtserial_ports);
+}
+
+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->set_guest_connected) {
+ vsc->set_guest_connected(port, false);
+ }
+ }
+ }
+}
+
+static void set_status(VirtIODevice *vdev, uint8_t status)
+{
+ VirtIOSerial *vser;
+ VirtIOSerialPort *port;
+
+ vser = VIRTIO_SERIAL(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 = VIRTIO_SERIAL(vdev);
+ guest_reset(vser);
+}
+
+static void virtio_serial_save(QEMUFile *f, void *opaque)
+{
+ /* The virtio device */
+ virtio_save(VIRTIO_DEVICE(opaque), f);
+}
+
+static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f)
+{
+ VirtIOSerial *s = VIRTIO_SERIAL(vdev);
+ VirtIOSerialPort *port;
+ uint32_t nr_active_ports;
+ unsigned int i, max_nr_ports;
+ struct virtio_console_config config;
+
+ /* The config space (ignored on the far end in current versions) */
+ get_config(vdev, (uint8_t *)&config);
+ qemu_put_be16s(f, &config.cols);
+ qemu_put_be16s(f, &config.rows);
+ qemu_put_be32s(f, &config.max_nr_ports);
+
+ /* The ports map */
+ max_nr_ports = s->serial.max_virtserial_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 void virtio_serial_post_load_timer_cb(void *opaque)
+{
+ uint32_t i;
+ VirtIOSerial *s = VIRTIO_SERIAL(opaque);
+ VirtIOSerialPort *port;
+ uint8_t host_connected;
+ VirtIOSerialPortClass *vsc;
+
+ if (!s->post_load) {
+ return;
+ }
+ for (i = 0 ; i < s->post_load->nr_active_ports; ++i) {
+ port = s->post_load->connected[i].port;
+ host_connected = s->post_load->connected[i].host_connected;
+ if (host_connected != port->host_connected) {
+ /*
+ * We have to let the guest know of the host connection
+ * status change
+ */
+ send_control_event(s, port->id, VIRTIO_CONSOLE_PORT_OPEN,
+ port->host_connected);
+ }
+ vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
+ if (vsc->set_guest_connected) {
+ vsc->set_guest_connected(port, port->guest_connected);
+ }
+ }
+ g_free(s->post_load->connected);
+ timer_free(s->post_load->timer);
+ g_free(s->post_load);
+ s->post_load = NULL;
+}
+
+static int fetch_active_ports_list(QEMUFile *f, int version_id,
+ VirtIOSerial *s, uint32_t nr_active_ports)
+{
+ uint32_t i;
+
+ s->post_load = g_malloc0(sizeof(*s->post_load));
+ s->post_load->nr_active_ports = nr_active_ports;
+ s->post_load->connected =
+ g_malloc0(sizeof(*s->post_load->connected) * nr_active_ports);
+
+ s->post_load->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
+ virtio_serial_post_load_timer_cb,
+ s);
+
+ /* Items in struct VirtIOSerialPort */
+ for (i = 0; i < nr_active_ports; i++) {
+ VirtIOSerialPort *port;
+ uint32_t id;
+
+ id = qemu_get_be32(f);
+ port = find_port_by_id(s, id);
+ if (!port) {
+ return -EINVAL;
+ }
+
+ port->guest_connected = qemu_get_byte(f);
+ s->post_load->connected[i].port = port;
+ s->post_load->connected[i].host_connected = qemu_get_byte(f);
+
+ 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);
+ }
+ }
+ }
+ timer_mod(s->post_load->timer, 1);
+ return 0;
+}
+
+static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id)
+{
+ if (version_id > 3) {
+ return -EINVAL;
+ }
+
+ /* The virtio device */
+ return virtio_load(VIRTIO_DEVICE(opaque), f, version_id);
+}
+
+static int virtio_serial_load_device(VirtIODevice *vdev, QEMUFile *f,
+ int version_id)
+{
+ VirtIOSerial *s = VIRTIO_SERIAL(vdev);
+ uint32_t max_nr_ports, nr_active_ports, ports_map;
+ unsigned int i;
+ int ret;
+ uint32_t tmp;
+
+ if (version_id < 2) {
+ return 0;
+ }
+
+ /* Unused */
+ qemu_get_be16s(f, (uint16_t *) &tmp);
+ qemu_get_be16s(f, (uint16_t *) &tmp);
+ qemu_get_be32s(f, &tmp);
+
+ max_nr_ports = s->serial.max_virtserial_ports;
+ 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);
+
+ if (nr_active_ports) {
+ ret = fetch_active_ports_list(f, version_id, s, nr_active_ports);
+ if (ret) {
+ return ret;
+ }
+ }
+ 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 = vser->serial.max_virtserial_ports;
+ for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
+ uint32_t map, zeroes;
+
+ map = vser->ports_map[i];
+ zeroes = ctz32(~map);
+ if (zeroes != 32) {
+ return zeroes + 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(vser, port_id, VIRTIO_CONSOLE_PORT_ADD, 1);
+}
+
+static void remove_port(VirtIOSerial *vser, uint32_t port_id)
+{
+ VirtIOSerialPort *port;
+
+ /*
+ * Don't mark port 0 removed -- we explicitly reserve it for
+ * backward compat with older guests, ensure a virtconsole device
+ * unplug retains the reservation.
+ */
+ if (port_id) {
+ unsigned int i;
+
+ i = port_id / 32;
+ vser->ports_map[i] &= ~(1U << (port_id % 32));
+ }
+
+ port = find_port_by_id(vser, port_id);
+ /*
+ * This function is only called from qdev's unplug callback; if we
+ * get a NULL port here, we're in trouble.
+ */
+ assert(port);
+
+ /* Flush out any unconsumed buffers first */
+ discard_vq_data(port->ovq, VIRTIO_DEVICE(port->vser));
+
+ send_control_event(vser, port->id, VIRTIO_CONSOLE_PORT_REMOVE, 1);
+}
+
+static void virtser_port_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev);
+ VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
+ VirtIOSerialBus *bus = VIRTIO_SERIAL_BUS(qdev_get_parent_bus(dev));
+ int max_nr_ports;
+ bool plugging_port0;
+ Error *err = NULL;
+
+ 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_setg(errp, "virtio-serial-bus: A port already exists at id %u",
+ port->id);
+ return;
+ }
+
+ if (port->name != NULL && find_port_by_name(port->name)) {
+ error_setg(errp, "virtio-serial-bus: A port already exists by name %s",
+ port->name);
+ return;
+ }
+
+ 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_setg(errp, "virtio-serial-bus: Maximum port limit for "
+ "this device reached");
+ return;
+ }
+ }
+ }
+
+ max_nr_ports = port->vser->serial.max_virtserial_ports;
+ if (port->id >= max_nr_ports) {
+ error_setg(errp, "virtio-serial-bus: Out-of-range port id specified, "
+ "max. allowed: %u", max_nr_ports - 1);
+ return;
+ }
+
+ vsc->realize(dev, &err);
+ if (err != NULL) {
+ error_propagate(errp, err);
+ return;
+ }
+
+ port->elem.out_num = 0;
+}
+
+static void virtser_port_device_plug(HotplugHandler *hotplug_dev,
+ DeviceState *dev, Error **errp)
+{
+ VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev);
+
+ 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(VIRTIO_DEVICE(hotplug_dev));
+}
+
+static void virtser_port_device_unrealize(DeviceState *dev, Error **errp)
+{
+ VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev);
+ VirtIOSerialPortClass *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(dev);
+ VirtIOSerial *vser = port->vser;
+
+ qemu_bh_delete(port->bh);
+ remove_port(port->vser, port->id);
+
+ QTAILQ_REMOVE(&vser->ports, port, next);
+
+ if (vsc->unrealize) {
+ vsc->unrealize(dev, errp);
+ }
+}
+
+static void virtio_serial_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOSerial *vser = VIRTIO_SERIAL(dev);
+ uint32_t i, max_supported_ports;
+
+ if (!vser->serial.max_virtserial_ports) {
+ error_setg(errp, "Maximum number of serial ports not specified");
+ return;
+ }
+
+ /* Each port takes 2 queues, and one pair is for the control queue */
+ max_supported_ports = VIRTIO_QUEUE_MAX / 2 - 1;
+
+ if (vser->serial.max_virtserial_ports > max_supported_ports) {
+ error_setg(errp, "maximum ports supported: %u", max_supported_ports);
+ return;
+ }
+
+ /* We don't support emergency write, skip it for now. */
+ /* TODO: cleaner fix, depending on host features. */
+ virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE,
+ offsetof(struct virtio_console_config, emerg_wr));
+
+ /* Spawn a new virtio-serial bus on which the ports will ride as devices */
+ qbus_create_inplace(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS,
+ dev, vdev->bus_name);
+ qbus_set_hotplug_handler(BUS(&vser->bus), DEVICE(vser), errp);
+ vser->bus.vser = vser;
+ QTAILQ_INIT(&vser->ports);
+
+ vser->bus.max_nr_ports = vser->serial.max_virtserial_ports;
+ vser->ivqs = g_malloc(vser->serial.max_virtserial_ports
+ * sizeof(VirtQueue *));
+ vser->ovqs = g_malloc(vser->serial.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->ports_map = g_malloc0(((vser->serial.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->post_load = NULL;
+
+ /*
+ * 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);
+
+ QLIST_INSERT_HEAD(&vserdevices.devices, vser, next);
+}
+
+static void virtio_serial_port_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *k = DEVICE_CLASS(klass);
+
+ set_bit(DEVICE_CATEGORY_INPUT, k->categories);
+ k->bus_type = TYPE_VIRTIO_SERIAL_BUS;
+ k->realize = virtser_port_device_realize;
+ k->unrealize = virtser_port_device_unrealize;
+ k->props = virtser_props;
+}
+
+static const 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_device_unrealize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOSerial *vser = VIRTIO_SERIAL(dev);
+
+ QLIST_REMOVE(vser, next);
+
+ unregister_savevm(dev, "virtio-console", vser);
+
+ g_free(vser->ivqs);
+ g_free(vser->ovqs);
+ g_free(vser->ports_map);
+ if (vser->post_load) {
+ g_free(vser->post_load->connected);
+ timer_del(vser->post_load->timer);
+ timer_free(vser->post_load->timer);
+ g_free(vser->post_load);
+ }
+ virtio_cleanup(vdev);
+}
+
+static Property virtio_serial_properties[] = {
+ DEFINE_PROP_UINT32("max_ports", VirtIOSerial, serial.max_virtserial_ports,
+ 31),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_serial_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+ HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
+
+ QLIST_INIT(&vserdevices.devices);
+
+ dc->props = virtio_serial_properties;
+ set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+ vdc->realize = virtio_serial_device_realize;
+ vdc->unrealize = virtio_serial_device_unrealize;
+ vdc->get_features = get_features;
+ vdc->get_config = get_config;
+ vdc->set_status = set_status;
+ vdc->reset = vser_reset;
+ vdc->save = virtio_serial_save_device;
+ vdc->load = virtio_serial_load_device;
+ hc->plug = virtser_port_device_plug;
+ hc->unplug = qdev_simple_device_unplug_cb;
+}
+
+static const TypeInfo virtio_device_info = {
+ .name = TYPE_VIRTIO_SERIAL,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VirtIOSerial),
+ .class_init = virtio_serial_class_init,
+ .interfaces = (InterfaceInfo[]) {
+ { TYPE_HOTPLUG_HANDLER },
+ { }
+ }
+};
+
+static void virtio_serial_register_types(void)
+{
+ type_register_static(&virtser_bus_info);
+ type_register_static(&virtio_serial_port_type_info);
+ type_register_static(&virtio_device_info);
+}
+
+type_init(virtio_serial_register_types)