/* * Virtio Serial / Console Support * * Copyright IBM, Corp. 2008 * Copyright Red Hat, Inc. 2009, 2010 * * Authors: * Christian Ehrhardt * Amit Shah * * This work is licensed under the terms of the GNU GPL, version 2. See * the COPYING file in the top-level directory. * */ #ifndef QEMU_VIRTIO_SERIAL_H #define QEMU_VIRTIO_SERIAL_H #include "standard-headers/linux/virtio_console.h" #include "hw/virtio/virtio.h" #include "qom/object.h" struct virtio_serial_conf { /* Max. number of ports we can have for a virtio-serial device */ uint32_t max_virtserial_ports; }; #define TYPE_VIRTIO_SERIAL_PORT "virtio-serial-port" OBJECT_DECLARE_TYPE(VirtIOSerialPort, VirtIOSerialPortClass, virtio_serial_port, VIRTIO_SERIAL_PORT) typedef struct VirtIOSerial VirtIOSerial; #define TYPE_VIRTIO_SERIAL_BUS "virtio-serial-bus" typedef struct VirtIOSerialBus VirtIOSerialBus; DECLARE_INSTANCE_CHECKER(VirtIOSerialBus, VIRTIO_SERIAL_BUS, TYPE_VIRTIO_SERIAL_BUS) struct VirtIOSerialPortClass { DeviceClass parent_class; /* Is this a device that binds with hvc in the guest? */ bool is_console; /* * The per-port (or per-app) realize function that's called when a * new device is found on the bus. */ DeviceRealize realize; /* * Per-port unrealize function that's called when a port gets * hot-unplugged or removed. */ DeviceUnrealize unrealize; /* Callbacks for guest events */ /* Guest opened/closed device. */ void (*set_guest_connected)(VirtIOSerialPort *port, int guest_connected); /* Enable/disable backend for virtio serial port */ void (*enable_backend)(VirtIOSerialPort *port, bool enable); /* Guest is now ready to accept data (virtqueues set up). */ void (*guest_ready)(VirtIOSerialPort *port); /* * Guest has enqueued a buffer for the host to write into. * Called each time a buffer is enqueued by the guest; * irrespective of whether there already were free buffers the * host could have consumed. * * This is dependent on both the guest and host end being * connected. */ void (*guest_writable)(VirtIOSerialPort *port); /* * Guest wrote some data to the port. This data is handed over to * the app via this callback. The app can return a size less than * 'len'. In this case, throttling will be enabled for this port. */ ssize_t (*have_data)(VirtIOSerialPort *port, const uint8_t *buf, ssize_t len); }; /* * This is the state that's shared between all the ports. Some of the * state is configurable via command-line options. Some of it can be * set by individual devices in their initfn routines. Some of the * state is set by the generic qdev device init routine. */ struct VirtIOSerialPort { DeviceState dev; QTAILQ_ENTRY(VirtIOSerialPort) next; /* * This field gives us the virtio device as well as the qdev bus * that we are associated with */ VirtIOSerial *vser; VirtQueue *ivq, *ovq; /* * This name is sent to the guest and exported via sysfs. * The guest could create symlinks based on this information. * The name is in the reverse fqdn format, like org.qemu.console.0 */ char *name; /* * This id helps identify ports between the guest and the host. * The guest sends a "header" with this id with each data packet * that it sends and the host can then find out which associated * device to send out this data to */ uint32_t id; /* * This is the elem that we pop from the virtqueue. A slow * backend that consumes guest data (e.g. the file backend for * qemu chardevs) can cause the guest to block till all the output * is flushed. This isn't desired, so we keep a note of the last * element popped and continue consuming it once the backend * becomes writable again. */ VirtQueueElement *elem; /* * The index and the offset into the iov buffer that was popped in * elem above. */ uint32_t iov_idx; uint64_t iov_offset; /* * When unthrottling we use a bottom-half to call flush_queued_data. */ QEMUBH *bh; /* Is the corresponding guest device open? */ bool guest_connected; /* Is this device open for IO on the host? */ bool host_connected; /* Do apps not want to receive data? */ bool throttled; }; /* 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; }; typedef struct VirtIOSerialPostLoad { QEMUTimer *timer; uint32_t nr_active_ports; struct { VirtIOSerialPort *port; uint8_t host_connected; } *connected; } VirtIOSerialPostLoad; struct VirtIOSerial { VirtIODevice parent_obj; VirtQueue *c_ivq, *c_ovq; /* Arrays of ivqs and ovqs: one per port */ VirtQueue **ivqs, **ovqs; VirtIOSerialBus bus; QTAILQ_HEAD(, VirtIOSerialPort) ports; QLIST_ENTRY(VirtIOSerial) next; /* bitmap for identifying active ports */ uint32_t *ports_map; struct VirtIOSerialPostLoad *post_load; virtio_serial_conf serial; uint64_t host_features; }; /* Interface to the virtio-serial bus */ /* * Open a connection to the port * Returns 0 on success (always). */ int virtio_serial_open(VirtIOSerialPort *port); /* * Close the connection to the port * Returns 0 on success (always). */ int virtio_serial_close(VirtIOSerialPort *port); /* * Send data to Guest */ ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf, size_t size); /* * Query whether a guest is ready to receive data. */ size_t virtio_serial_guest_ready(VirtIOSerialPort *port); /* * Flow control: Ports can signal to the virtio-serial core to stop * sending data or re-start sending data, depending on the 'throttle' * value here. */ void virtio_serial_throttle_port(VirtIOSerialPort *port, bool throttle); #define TYPE_VIRTIO_SERIAL "virtio-serial-device" DECLARE_INSTANCE_CHECKER(VirtIOSerial, VIRTIO_SERIAL, TYPE_VIRTIO_SERIAL) #endif