spice: add virtio-serial based spice vmchannel backend.

Adds the spicevmc device.  This is a communication channel between the
spice client and the guest.  It is used to send display information and
mouse events from the spice clients to the guest.

2 files changed, 263 insertions, 0 deletions

diff --git a/Makefile.target b/Makefile.target
index df7eebb7d..87c409aad 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -202,6 +202,7 @@ obj-i386-y += device-hotplug.o pci-hotplug.o smbios.o wdt_ib700.o
 obj-i386-y += debugcon.o multiboot.o
 obj-i386-y += pc_piix.o
 obj-i386-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o
+obj-i386-$(CONFIG_SPICE) += spice-vmc.o
 
 # shared objects
 obj-ppc-y = ppc.o
diff --git a/hw/spice-vmc.c b/hw/spice-vmc.c
new file mode 100644
index 000000000..1255d465f
--- /dev/null
+++ b/hw/spice-vmc.c
@@ -0,0 +1,262 @@
+/*
+
+ Spice Virtual Machine Channel (VMC).
+
+ A virtio-serial port used for spice to guest communication, over
+ which spice client and a daemon in the guest operating system
+ communicate.
+
+ Replaces the old vdi_port PCI device.
+
+*/
+
+#include <stdio.h>
+#include <stdbool.h>
+#include <spice.h>
+#include <spice-experimental.h>
+
+#include "virtio-serial.h"
+#include "ui/qemu-spice.h"
+
+#define VMC_GUEST_DEVICE_NAME "com.redhat.spice.0"
+#define VMC_DEVICE_NAME       "spicevmc"
+
+/* windows guest driver bug workaround */
+#define VMC_MAX_HOST_WRITE    2048
+
+#define dprintf(_svc, _level, _fmt, ...)                                \
+    do {                                                                \
+        static unsigned __dprintf_counter = 0;                          \
+        if (_svc->debug >= _level) {                                    \
+            fprintf(stderr, "svc: %3d: " _fmt, ++__dprintf_counter, ## __VA_ARGS__);\
+        }                                                               \
+    } while (0)
+
+typedef struct SpiceVirtualChannel {
+    VirtIOSerialPort         port;
+    VMChangeStateEntry       *vmstate;
+    SpiceCharDeviceInstance  sin;
+    char                     *subtype;
+    bool                     active;
+    uint8_t                  *buffer;
+    uint8_t                  *datapos;
+    ssize_t                  bufsize, datalen;
+    uint32_t                 debug;
+} SpiceVirtualChannel;
+
+static int vmc_write(SpiceCharDeviceInstance *sin, const uint8_t *buf, int len)
+{
+    SpiceVirtualChannel *svc = container_of(sin, SpiceVirtualChannel, sin);
+    ssize_t out = 0;
+    ssize_t last_out;
+    uint8_t* p = (uint8_t*)buf;
+
+    while (len > 0) {
+        last_out = virtio_serial_write(&svc->port, p,
+                            MIN(len, VMC_MAX_HOST_WRITE));
+        if (last_out > 0) {
+            out += last_out;
+            len -= last_out;
+            p += last_out;
+        } else {
+            break;
+        }
+    }
+
+    dprintf(svc, 3, "%s: %lu/%zd\n", __func__, out, len + out);
+    return out;
+}
+
+static int vmc_read(SpiceCharDeviceInstance *sin, uint8_t *buf, int len)
+{
+    SpiceVirtualChannel *svc = container_of(sin, SpiceVirtualChannel, sin);
+    int bytes = MIN(len, svc->datalen);
+
+    dprintf(svc, 2, "%s: %p %d/%d/%zd\n", __func__, svc->datapos, len, bytes, svc->datalen);
+    if (bytes > 0) {
+        memcpy(buf, svc->datapos, bytes);
+        svc->datapos += bytes;
+        svc->datalen -= bytes;
+        assert(svc->datalen >= 0);
+        if (svc->datalen == 0) {
+            svc->datapos = 0;
+            virtio_serial_throttle_port(&svc->port, false);
+            // ^^^ !!! may call vmc_have_data, so don't touch svc after it!
+        }
+    }
+    return bytes;
+}
+
+static SpiceCharDeviceInterface vmc_interface = {
+    .base.type          = SPICE_INTERFACE_CHAR_DEVICE,
+    .base.description   = "spice virtual channel char device",
+    .base.major_version = SPICE_INTERFACE_CHAR_DEVICE_MAJOR,
+    .base.minor_version = SPICE_INTERFACE_CHAR_DEVICE_MINOR,
+    .write              = vmc_write,
+    .read               = vmc_read,
+};
+
+static void vmc_register_interface(SpiceVirtualChannel *svc)
+{
+    if (svc->active) {
+        return;
+    }
+    dprintf(svc, 1, "%s\n", __func__);
+    svc->sin.base.sif = &vmc_interface.base;
+    qemu_spice_add_interface(&svc->sin.base);
+    svc->active = true;
+}
+
+static void vmc_unregister_interface(SpiceVirtualChannel *svc)
+{
+    if (!svc->active) {
+        return;
+    }
+    dprintf(svc, 1, "%s\n", __func__);
+    spice_server_remove_interface(&svc->sin.base);
+    svc->active = false;
+}
+
+
+static void vmc_change_state_handler(void *opaque, int running, int reason)
+{
+    SpiceVirtualChannel *svc = opaque;
+
+    if (running && svc->active) {
+        spice_server_char_device_wakeup(&svc->sin);
+    }
+}
+
+/*
+ * virtio-serial callbacks
+ */
+
+static void vmc_guest_open(VirtIOSerialPort *port)
+{
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+
+    dprintf(svc, 1, "%s\n", __func__);
+    vmc_register_interface(svc);
+}
+
+static void vmc_guest_close(VirtIOSerialPort *port)
+{
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+
+    dprintf(svc, 1, "%s\n", __func__);
+    vmc_unregister_interface(svc);
+}
+
+static void vmc_guest_ready(VirtIOSerialPort *port)
+{
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+
+    dprintf(svc, 1, "%s\n", __func__);
+    if (svc->active) {
+        spice_server_char_device_wakeup(&svc->sin);
+    }
+}
+
+static void vmc_have_data(VirtIOSerialPort *port, const uint8_t *buf, size_t len)
+{
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+
+    dprintf(svc, 2, "%s: %zd\n", __func__, len);
+    assert(svc->datalen == 0);
+    if (svc->bufsize < len) {
+        svc->bufsize = len;
+        svc->buffer = qemu_realloc(svc->buffer, svc->bufsize);
+    }
+    memcpy(svc->buffer, buf, len);
+    svc->datapos = svc->buffer;
+    svc->datalen = len;
+    virtio_serial_throttle_port(&svc->port, true);
+    spice_server_char_device_wakeup(&svc->sin);
+}
+
+static void vmc_print_optional_subtypes(void)
+{
+    const char** psubtype = spice_server_char_device_recognized_subtypes();
+    int i;
+
+    fprintf(stderr, "supported subtypes: ");
+    for(i=0; *psubtype != NULL; ++psubtype, ++i) {
+        if (i == 0) {
+            fprintf(stderr, *psubtype);
+        } else {
+            fprintf(stderr, ", %s", *psubtype);
+        }
+    }
+    fprintf(stderr, "\n");
+}
+
+static int vmc_initfn(VirtIOSerialDevice *dev)
+{
+    VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, &dev->qdev);
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+    const char** psubtype = spice_server_char_device_recognized_subtypes();
+    const char *subtype = NULL;
+
+    if (!using_spice) {
+        return -1;
+    }
+
+    dprintf(svc, 1, "%s\n", __func__);
+
+    if (svc->subtype == NULL) {
+        svc->subtype = strdup("vdagent");
+    }
+
+    for(;*psubtype != NULL; ++psubtype) {
+        if (strcmp(svc->subtype, *psubtype) == 0) {
+            subtype = *psubtype;
+            break;
+        }
+    }
+    if (subtype == NULL) {
+        fprintf(stderr, "spice-vmc: unsupported subtype\n");
+        vmc_print_optional_subtypes();
+        return -1;
+    }
+    port->name = qemu_strdup(VMC_GUEST_DEVICE_NAME);
+    svc->vmstate = qemu_add_vm_change_state_handler
+        (vmc_change_state_handler, svc);
+    svc->sin.subtype = svc->subtype;
+    virtio_serial_open(port);
+    return 0;
+}
+
+static int vmc_exitfn(VirtIOSerialDevice *dev)
+{
+    VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, &dev->qdev);
+    SpiceVirtualChannel *svc = DO_UPCAST(SpiceVirtualChannel, port, port);
+
+    dprintf(svc, 1, "%s\n", __func__);
+    vmc_unregister_interface(svc);
+    qemu_del_vm_change_state_handler(svc->vmstate);
+    virtio_serial_close(port);
+    return 0;
+}
+
+static VirtIOSerialPortInfo vmc_info = {
+    .qdev.name     = VMC_DEVICE_NAME,
+    .qdev.size     = sizeof(SpiceVirtualChannel),
+    .init          = vmc_initfn,
+    .exit          = vmc_exitfn,
+    .guest_open    = vmc_guest_open,
+    .guest_close   = vmc_guest_close,
+    .guest_ready   = vmc_guest_ready,
+    .have_data     = vmc_have_data,
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("nr", SpiceVirtualChannel, port.id, VIRTIO_CONSOLE_BAD_ID),
+        DEFINE_PROP_UINT32("debug", SpiceVirtualChannel, debug, 1),
+        DEFINE_PROP_STRING("subtype", SpiceVirtualChannel, subtype),
+        DEFINE_PROP_END_OF_LIST(),
+    }
+};
+
+static void vmc_register(void)
+{
+    virtio_serial_port_qdev_register(&vmc_info);
+}
+device_init(vmc_register)