hw/virtio-console.c

   1 /*
   2  * Virtio Console and Generic Serial Port Devices
   3  *
   4  * Copyright Red Hat, Inc. 2009, 2010
   5  *
   6  * Authors:
   7  *  Amit Shah <amit.shah@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  */
  12
  13 #include "qemu-char.h"
  14 #include "qemu-error.h"
  15 #include "virtio-serial.h"
  16
  17 typedef struct VirtConsole {
  18     VirtIOSerialPort port;
  19     CharDriverState *chr;
  20 } VirtConsole;
  21
  22
  23 /* Callback function that's called when the guest sends us data */
  24 static ssize_t flush_buf(VirtIOSerialPort *port, const uint8_t *buf, size_t len)
  25 {
  26     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
  27
  28     return qemu_chr_write(vcon->chr, buf, len);
  29 }
  30
  31 /* Callback function that's called when the guest opens the port */
  32 static void guest_open(VirtIOSerialPort *port)
  33 {
  34     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
  35
  36     qemu_chr_guest_open(vcon->chr);
  37 }
  38
  39 /* Callback function that's called when the guest closes the port */
  40 static void guest_close(VirtIOSerialPort *port)
  41 {
  42     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
  43
  44     qemu_chr_guest_close(vcon->chr);
  45 }
  46
  47 /* Readiness of the guest to accept data on a port */
  48 static int chr_can_read(void *opaque)
  49 {
  50     VirtConsole *vcon = opaque;
  51
  52     return virtio_serial_guest_ready(&vcon->port);
  53 }
  54
  55 /* Send data from a char device over to the guest */
  56 static void chr_read(void *opaque, const uint8_t *buf, int size)
  57 {
  58     VirtConsole *vcon = opaque;
  59
  60     virtio_serial_write(&vcon->port, buf, size);
  61 }
  62
  63 static void chr_event(void *opaque, int event)
  64 {
  65     VirtConsole *vcon = opaque;
  66
  67     switch (event) {
  68     case CHR_EVENT_OPENED:
  69         virtio_serial_open(&vcon->port);
  70         break;
  71     case CHR_EVENT_CLOSED:
  72         virtio_serial_close(&vcon->port);
  73         break;
  74     }
  75 }
  76
  77 static int generic_port_init(VirtConsole *vcon, VirtIOSerialPort *port)
  78 {
  79     if (vcon->chr) {
  80         qemu_chr_add_handlers(vcon->chr, chr_can_read, chr_read, chr_event,
  81                               vcon);
  82         vcon->port.info->have_data = flush_buf;
  83         vcon->port.info->guest_open = guest_open;
  84         vcon->port.info->guest_close = guest_close;
  85     }
  86     return 0;
  87 }
  88
  89 /* Virtio Console Ports */
  90 static int virtconsole_initfn(VirtIOSerialPort *port)
  91 {
  92     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
  93
  94     return generic_port_init(vcon, port);
  95 }
  96
  97 static int virtconsole_exitfn(VirtIOSerialPort *port)
  98 {
  99     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
 100
 101     if (vcon->chr) {
 102         /*
 103          * Instead of closing the chardev, free it so it can be used
 104          * for other purposes.
 105          */
 106         qemu_chr_add_handlers(vcon->chr, NULL, NULL, NULL, NULL);
 107     }
 108
 109     return 0;
 110 }
 111
 112 static VirtIOSerialPortInfo virtconsole_info = {
 113     .qdev.name     = "virtconsole",
 114     .qdev.size     = sizeof(VirtConsole),
 115     .is_console    = true,
 116     .init          = virtconsole_initfn,
 117     .exit          = virtconsole_exitfn,
 118     .qdev.props = (Property[]) {
 119         DEFINE_PROP_UINT32("nr", VirtConsole, port.id, VIRTIO_CONSOLE_BAD_ID),
 120         DEFINE_PROP_CHR("chardev", VirtConsole, chr),
 121         DEFINE_PROP_STRING("name", VirtConsole, port.name),
 122         DEFINE_PROP_END_OF_LIST(),
 123     },
 124 };
 125
 126 static void virtconsole_register(void)
 127 {
 128     virtio_serial_port_qdev_register(&virtconsole_info);
 129 }
 130 device_init(virtconsole_register)
 131
 132 /* Generic Virtio Serial Ports */
 133 static int virtserialport_initfn(VirtIOSerialPort *port)
 134 {
 135     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
 136
 137     if (port->id == 0) {
 138         /*
 139          * Disallow a generic port at id 0, that's reserved for
 140          * console ports.
 141          */
 142         error_report("Port number 0 on virtio-serial devices reserved for virtconsole devices for backward compatibility.");
 143         return -1;
 144     }
 145     return generic_port_init(vcon, port);
 146 }
 147
 148 static VirtIOSerialPortInfo virtserialport_info = {
 149     .qdev.name     = "virtserialport",
 150     .qdev.size     = sizeof(VirtConsole),
 151     .init          = virtserialport_initfn,
 152     .exit          = virtconsole_exitfn,
 153     .qdev.props = (Property[]) {
 154         DEFINE_PROP_UINT32("nr", VirtConsole, port.id, VIRTIO_CONSOLE_BAD_ID),
 155         DEFINE_PROP_CHR("chardev", VirtConsole, chr),
 156         DEFINE_PROP_STRING("name", VirtConsole, port.name),
 157         DEFINE_PROP_END_OF_LIST(),
 158     },
 159 };
 160
 161 static void virtserialport_register(void)
 162 {
 163     virtio_serial_port_qdev_register(&virtserialport_info);
 164 }
 165 device_init(virtserialport_register)