qemu-e2k/hw/char/virtio-console.c

310 lines
9.5 KiB
C
Raw Normal View History

virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
/*
* Virtio Console and Generic Serial Port Devices
*
* Copyright Red Hat, Inc. 2009, 2010
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
*
* Authors:
* Amit Shah <amit.shah@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "chardev/char-fe.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "trace.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
#include "hw/virtio/virtio-serial.h"
#include "qapi/error.h"
#include "qapi/qapi-events-char.h"
#include "qom/object.h"
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
#define TYPE_VIRTIO_CONSOLE_SERIAL_PORT "virtserialport"
typedef struct VirtConsole VirtConsole;
DECLARE_INSTANCE_CHECKER(VirtConsole, VIRTIO_CONSOLE,
TYPE_VIRTIO_CONSOLE_SERIAL_PORT)
struct VirtConsole {
VirtIOSerialPort parent_obj;
CharBackend chr;
guint watch;
};
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
/*
* Callback function that's called from chardevs when backend becomes
* writable.
*/
static gboolean chr_write_unblocked(GIOChannel *chan, GIOCondition cond,
void *opaque)
{
VirtConsole *vcon = opaque;
vcon->watch = 0;
virtio_serial_throttle_port(VIRTIO_SERIAL_PORT(vcon), false);
return FALSE;
}
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
/* Callback function that's called when the guest sends us data */
static ssize_t flush_buf(VirtIOSerialPort *port,
const uint8_t *buf, ssize_t len)
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
{
VirtConsole *vcon = VIRTIO_CONSOLE(port);
ssize_t ret;
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
if (!qemu_chr_fe_backend_connected(&vcon->chr)) {
/* If there's no backend, we can just say we consumed all data. */
return len;
}
ret = qemu_chr_fe_write(&vcon->chr, buf, len);
trace_virtio_console_flush_buf(port->id, len, ret);
if (ret < len) {
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);
/*
* Ideally we'd get a better error code than just -1, but
* that's what the chardev interface gives us right now. If
* we had a finer-grained message, like -EPIPE, we could close
* this connection.
*/
if (ret < 0)
ret = 0;
/* XXX we should be queuing data to send later for the
* console devices too rather than silently dropping
* console data on EAGAIN. The Linux virtio-console
* hvc driver though does sends with spinlocks held,
* so if we enable throttling that'll stall the entire
* guest kernel, not merely the process writing to the
* console.
*
* While we could queue data for later write without
* enabling throttling, this would result in the guest
* being able to trigger arbitrary memory usage in QEMU
* buffering data for later writes.
*
* So fixing this problem likely requires fixing the
* Linux virtio-console hvc driver to not hold spinlocks
* while writing, and instead merely block the process
* that's writing. QEMU would then need some way to detect
* if the guest had the fixed driver too, before we can
* use throttling on host side.
*/
if (!k->is_console) {
virtio_serial_throttle_port(port, true);
if (!vcon->watch) {
vcon->watch = qemu_chr_fe_add_watch(&vcon->chr,
G_IO_OUT|G_IO_HUP,
chr_write_unblocked, vcon);
}
}
}
return ret;
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
}
/* Callback function that's called when the guest opens/closes the port */
static void set_guest_connected(VirtIOSerialPort *port, int guest_connected)
{
VirtConsole *vcon = VIRTIO_CONSOLE(port);
DeviceState *dev = DEVICE(port);
virtio-console: set frontend open permanently for console devs The virtio-console.c file handles both serial consoles and interactive consoles, since they're backed by the same device model. Since serial devices are expected to be reliable and need to notify the guest when the backend is opened or closed, the virtio-console.c file wires up support for chardev events. This affects both serial consoles and interactive consoles, using a network connection based chardev backend such as 'socket', but not when using a PTY based backend or plain 'file' backends. When the host side is not connected the handle_output() method in virtio-serial-bus.c will drop any data sent by the guest, before it even reaches the virtio-console.c code. This means that if the chardev has a logfile configured, the data will never get logged. Consider for example, configuring a x86_64 guest with a plain UART serial port -chardev socket,id=charserial1,host=127.0.0.1,port=9001,server,nowait,logfile=console1.log,logappend=on -device isa-serial,chardev=charserial1,id=serial1 vs a s390 guest which has to use the virtio-console port -chardev socket,id=charconsole1,host=127.0.0.1,port=9000,server,nowait,logfile=console2.log,logappend=on -device virtconsole,chardev=charconsole1,id=console1 The isa-serial one gets data written to the log regardless of whether a client is connected, while the virtioconsole one only gets data written to the log when a client is connected. There is no need for virtio-serial-bus.c to aggressively drop the data for console devices, as the chardev code is prefectly capable of discarding the data itself. So this patch changes virtconsole devices so that they are always marked as having the host side open. This ensures that the guest OS will always send any data it has (Linux virtio-console hvc driver actually ignores the host open state and sends data regardless, but we should not rely on that), and also prevents the virtio-serial-bus code prematurely discarding data. The behaviour of virtserialport devices is *not* changed, only virtconsole, because for the former, it is important that the guest OSknow exactly when the host side is opened / closed so it can do any protocol re-negotiation that may be required. Fixes bug: https://bugs.launchpad.net/qemu/+bug/1599214 Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1470241360-3574-2-git-send-email-berrange@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-08-03 18:22:36 +02:00
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);
if (!k->is_console) {
qemu_chr_fe_set_open(&vcon->chr, guest_connected);
}
if (dev->id) {
qapi_event_send_vserport_change(dev->id, guest_connected);
}
}
static void guest_writable(VirtIOSerialPort *port)
{
VirtConsole *vcon = VIRTIO_CONSOLE(port);
qemu_chr_fe_accept_input(&vcon->chr);
}
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
/* Readiness of the guest to accept data on a port */
static int chr_can_read(void *opaque)
{
VirtConsole *vcon = opaque;
return virtio_serial_guest_ready(VIRTIO_SERIAL_PORT(vcon));
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
}
/* Send data from a char device over to the guest */
static void chr_read(void *opaque, const uint8_t *buf, int size)
{
VirtConsole *vcon = opaque;
VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(vcon);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
trace_virtio_console_chr_read(port->id, size);
virtio_serial_write(port, buf, size);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
}
static void chr_event(void *opaque, QEMUChrEvent event)
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
{
VirtConsole *vcon = opaque;
VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(vcon);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
trace_virtio_console_chr_event(port->id, event);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
switch (event) {
case CHR_EVENT_OPENED:
virtio_serial_open(port);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
break;
case CHR_EVENT_CLOSED:
if (vcon->watch) {
g_source_remove(vcon->watch);
vcon->watch = 0;
}
virtio_serial_close(port);
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
break;
case CHR_EVENT_BREAK:
case CHR_EVENT_MUX_IN:
case CHR_EVENT_MUX_OUT:
/* Ignore */
break;
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
}
}
static int chr_be_change(void *opaque)
{
VirtConsole *vcon = opaque;
VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(vcon);
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);
if (k->is_console) {
qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
NULL, chr_be_change, vcon, NULL, true);
} else {
qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
chr_event, chr_be_change, vcon, NULL, false);
}
if (vcon->watch) {
g_source_remove(vcon->watch);
vcon->watch = qemu_chr_fe_add_watch(&vcon->chr,
G_IO_OUT | G_IO_HUP,
chr_write_unblocked, vcon);
}
return 0;
}
static void virtconsole_enable_backend(VirtIOSerialPort *port, bool enable)
{
VirtConsole *vcon = VIRTIO_CONSOLE(port);
if (!qemu_chr_fe_backend_connected(&vcon->chr)) {
return;
}
if (enable) {
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);
qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
k->is_console ? NULL : chr_event,
chr_be_change, vcon, NULL, false);
} else {
qemu_chr_fe_set_handlers(&vcon->chr, NULL, NULL, NULL,
NULL, NULL, NULL, false);
}
}
static void virtconsole_realize(DeviceState *dev, Error **errp)
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
{
VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev);
VirtConsole *vcon = VIRTIO_CONSOLE(dev);
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(dev);
if (port->id == 0 && !k->is_console) {
error_setg(errp, "Port number 0 on virtio-serial devices reserved "
"for virtconsole devices for backward compatibility.");
return;
}
if (qemu_chr_fe_backend_connected(&vcon->chr)) {
virtio-console: set frontend open permanently for console devs The virtio-console.c file handles both serial consoles and interactive consoles, since they're backed by the same device model. Since serial devices are expected to be reliable and need to notify the guest when the backend is opened or closed, the virtio-console.c file wires up support for chardev events. This affects both serial consoles and interactive consoles, using a network connection based chardev backend such as 'socket', but not when using a PTY based backend or plain 'file' backends. When the host side is not connected the handle_output() method in virtio-serial-bus.c will drop any data sent by the guest, before it even reaches the virtio-console.c code. This means that if the chardev has a logfile configured, the data will never get logged. Consider for example, configuring a x86_64 guest with a plain UART serial port -chardev socket,id=charserial1,host=127.0.0.1,port=9001,server,nowait,logfile=console1.log,logappend=on -device isa-serial,chardev=charserial1,id=serial1 vs a s390 guest which has to use the virtio-console port -chardev socket,id=charconsole1,host=127.0.0.1,port=9000,server,nowait,logfile=console2.log,logappend=on -device virtconsole,chardev=charconsole1,id=console1 The isa-serial one gets data written to the log regardless of whether a client is connected, while the virtioconsole one only gets data written to the log when a client is connected. There is no need for virtio-serial-bus.c to aggressively drop the data for console devices, as the chardev code is prefectly capable of discarding the data itself. So this patch changes virtconsole devices so that they are always marked as having the host side open. This ensures that the guest OS will always send any data it has (Linux virtio-console hvc driver actually ignores the host open state and sends data regardless, but we should not rely on that), and also prevents the virtio-serial-bus code prematurely discarding data. The behaviour of virtserialport devices is *not* changed, only virtconsole, because for the former, it is important that the guest OSknow exactly when the host side is opened / closed so it can do any protocol re-negotiation that may be required. Fixes bug: https://bugs.launchpad.net/qemu/+bug/1599214 Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1470241360-3574-2-git-send-email-berrange@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-08-03 18:22:36 +02:00
/*
* For consoles we don't block guest data transfer just
* because nothing is connected - we'll just let it go
* whetherever the chardev wants - /dev/null probably.
*
* For serial ports we need 100% reliable data transfer
* so we use the opened/closed signals from chardev to
* trigger open/close of the device
*/
if (k->is_console) {
qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
NULL, chr_be_change,
vcon, NULL, true);
virtio-console: set frontend open permanently for console devs The virtio-console.c file handles both serial consoles and interactive consoles, since they're backed by the same device model. Since serial devices are expected to be reliable and need to notify the guest when the backend is opened or closed, the virtio-console.c file wires up support for chardev events. This affects both serial consoles and interactive consoles, using a network connection based chardev backend such as 'socket', but not when using a PTY based backend or plain 'file' backends. When the host side is not connected the handle_output() method in virtio-serial-bus.c will drop any data sent by the guest, before it even reaches the virtio-console.c code. This means that if the chardev has a logfile configured, the data will never get logged. Consider for example, configuring a x86_64 guest with a plain UART serial port -chardev socket,id=charserial1,host=127.0.0.1,port=9001,server,nowait,logfile=console1.log,logappend=on -device isa-serial,chardev=charserial1,id=serial1 vs a s390 guest which has to use the virtio-console port -chardev socket,id=charconsole1,host=127.0.0.1,port=9000,server,nowait,logfile=console2.log,logappend=on -device virtconsole,chardev=charconsole1,id=console1 The isa-serial one gets data written to the log regardless of whether a client is connected, while the virtioconsole one only gets data written to the log when a client is connected. There is no need for virtio-serial-bus.c to aggressively drop the data for console devices, as the chardev code is prefectly capable of discarding the data itself. So this patch changes virtconsole devices so that they are always marked as having the host side open. This ensures that the guest OS will always send any data it has (Linux virtio-console hvc driver actually ignores the host open state and sends data regardless, but we should not rely on that), and also prevents the virtio-serial-bus code prematurely discarding data. The behaviour of virtserialport devices is *not* changed, only virtconsole, because for the former, it is important that the guest OSknow exactly when the host side is opened / closed so it can do any protocol re-negotiation that may be required. Fixes bug: https://bugs.launchpad.net/qemu/+bug/1599214 Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1470241360-3574-2-git-send-email-berrange@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-08-03 18:22:36 +02:00
virtio_serial_open(port);
} else {
qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
chr_event, chr_be_change,
vcon, NULL, false);
virtio-console: set frontend open permanently for console devs The virtio-console.c file handles both serial consoles and interactive consoles, since they're backed by the same device model. Since serial devices are expected to be reliable and need to notify the guest when the backend is opened or closed, the virtio-console.c file wires up support for chardev events. This affects both serial consoles and interactive consoles, using a network connection based chardev backend such as 'socket', but not when using a PTY based backend or plain 'file' backends. When the host side is not connected the handle_output() method in virtio-serial-bus.c will drop any data sent by the guest, before it even reaches the virtio-console.c code. This means that if the chardev has a logfile configured, the data will never get logged. Consider for example, configuring a x86_64 guest with a plain UART serial port -chardev socket,id=charserial1,host=127.0.0.1,port=9001,server,nowait,logfile=console1.log,logappend=on -device isa-serial,chardev=charserial1,id=serial1 vs a s390 guest which has to use the virtio-console port -chardev socket,id=charconsole1,host=127.0.0.1,port=9000,server,nowait,logfile=console2.log,logappend=on -device virtconsole,chardev=charconsole1,id=console1 The isa-serial one gets data written to the log regardless of whether a client is connected, while the virtioconsole one only gets data written to the log when a client is connected. There is no need for virtio-serial-bus.c to aggressively drop the data for console devices, as the chardev code is prefectly capable of discarding the data itself. So this patch changes virtconsole devices so that they are always marked as having the host side open. This ensures that the guest OS will always send any data it has (Linux virtio-console hvc driver actually ignores the host open state and sends data regardless, but we should not rely on that), and also prevents the virtio-serial-bus code prematurely discarding data. The behaviour of virtserialport devices is *not* changed, only virtconsole, because for the former, it is important that the guest OSknow exactly when the host side is opened / closed so it can do any protocol re-negotiation that may be required. Fixes bug: https://bugs.launchpad.net/qemu/+bug/1599214 Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1470241360-3574-2-git-send-email-berrange@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-08-03 18:22:36 +02:00
}
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
}
}
qdev: Unrealize must not fail Devices may have component devices and buses. Device realization may fail. Realization is recursive: a device's realize() method realizes its components, and device_set_realized() realizes its buses (which should in turn realize the devices on that bus, except bus_set_realized() doesn't implement that, yet). When realization of a component or bus fails, we need to roll back: unrealize everything we realized so far. If any of these unrealizes failed, the device would be left in an inconsistent state. Must not happen. device_set_realized() lets it happen: it ignores errors in the roll back code starting at label child_realize_fail. Since realization is recursive, unrealization must be recursive, too. But how could a partly failed unrealize be rolled back? We'd have to re-realize, which can fail. This design is fundamentally broken. device_set_realized() does not roll back at all. Instead, it keeps unrealizing, ignoring further errors. It can screw up even for a device with no buses: if the lone dc->unrealize() fails, it still unregisters vmstate, and calls listeners' unrealize() callback. bus_set_realized() does not roll back either. Instead, it stops unrealizing. Fortunately, no unrealize method can fail, as we'll see below. To fix the design error, drop parameter @errp from all the unrealize methods. Any unrealize method that uses @errp now needs an update. This leads us to unrealize() methods that can fail. Merely passing it to another unrealize method cannot cause failure, though. Here are the ones that do other things with @errp: * virtio_serial_device_unrealize() Fails when qbus_set_hotplug_handler() fails, but still does all the other work. On failure, the device would stay realized with its resources completely gone. Oops. Can't happen, because qbus_set_hotplug_handler() can't actually fail here. Pass &error_abort to qbus_set_hotplug_handler() instead. * hw/ppc/spapr_drc.c's unrealize() Fails when object_property_del() fails, but all the other work is already done. On failure, the device would stay realized with its vmstate registration gone. Oops. Can't happen, because object_property_del() can't actually fail here. Pass &error_abort to object_property_del() instead. * spapr_phb_unrealize() Fails and bails out when remove_drcs() fails, but other work is already done. On failure, the device would stay realized with some of its resources gone. Oops. remove_drcs() fails only when chassis_from_bus()'s object_property_get_uint() fails, and it can't here. Pass &error_abort to remove_drcs() instead. Therefore, no unrealize method can fail before this patch. device_set_realized()'s recursive unrealization via bus uses object_property_set_bool(). Can't drop @errp there, so pass &error_abort. We similarly unrealize with object_property_set_bool() elsewhere, always ignoring errors. Pass &error_abort instead. Several unrealize methods no longer handle errors from other unrealize methods: virtio_9p_device_unrealize(), virtio_input_device_unrealize(), scsi_qdev_unrealize(), ... Much of the deleted error handling looks wrong anyway. One unrealize methods no longer ignore such errors: usb_ehci_pci_exit(). Several realize methods no longer ignore errors when rolling back: v9fs_device_realize_common(), pci_qdev_unrealize(), spapr_phb_realize(), usb_qdev_realize(), vfio_ccw_realize(), virtio_device_realize(). Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20200505152926.18877-17-armbru@redhat.com>
2020-05-05 17:29:24 +02:00
static void virtconsole_unrealize(DeviceState *dev)
{
VirtConsole *vcon = VIRTIO_CONSOLE(dev);
if (vcon->watch) {
g_source_remove(vcon->watch);
}
}
static void virtconsole_class_init(ObjectClass *klass, void *data)
{
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_CLASS(klass);
k->is_console = true;
}
static const TypeInfo virtconsole_info = {
.name = "virtconsole",
.parent = TYPE_VIRTIO_CONSOLE_SERIAL_PORT,
.class_init = virtconsole_class_init,
virtio-console: qdev conversion, new virtio-serial-bus This commit converts the virtio-console device to create a new virtio-serial bus that can host console and generic serial ports. The file hosting this code is now called virtio-serial-bus.c. The virtio console is now a very simple qdev device that sits on the virtio-serial-bus and communicates between the bus and qemu's chardevs. This commit also includes a few changes to the virtio backing code for pci and s390 to spawn the virtio-serial bus. As a result of the qdev conversion, we get rid of a lot of legacy code. The old-style way of instantiating a virtio console using -virtioconsole ... is maintained, but the new, preferred way is to use -device virtio-serial -device virtconsole,chardev=... With this commit, multiple devices as well as multiple ports with a single device can be supported. For multiple ports support, each port gets an IO vq pair. Since the guest needs to know in advance how many vqs a particular device will need, we have to set this number as a property of the virtio-serial device and also as a config option. In addition, we also spawn a pair of control IO vqs. This is an internal channel meant for guest-host communication for things like port open/close, sending port properties over to the guest, etc. This commit is a part of a series of other commits to get the full implementation of multiport support. Future commits will add other support as well as ride on the savevm version that we bump up here. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-19 20:06:52 +01:00
};
static Property virtserialport_properties[] = {
DEFINE_PROP_CHR("chardev", VirtConsole, chr),
DEFINE_PROP_END_OF_LIST(),
};
static void virtserialport_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_CLASS(klass);
k->realize = virtconsole_realize;
k->unrealize = virtconsole_unrealize;
k->have_data = flush_buf;
k->set_guest_connected = set_guest_connected;
k->enable_backend = virtconsole_enable_backend;
k->guest_writable = guest_writable;
device_class_set_props(dc, virtserialport_properties);
}
static const TypeInfo virtserialport_info = {
.name = TYPE_VIRTIO_CONSOLE_SERIAL_PORT,
.parent = TYPE_VIRTIO_SERIAL_PORT,
.instance_size = sizeof(VirtConsole),
.class_init = virtserialport_class_init,
};
static void virtconsole_register_types(void)
{
type_register_static(&virtserialport_info);
type_register_static(&virtconsole_info);
}
type_init(virtconsole_register_types)