qemu-e2k/hw/s390x/virtio-ccw.h

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

94 lines
2.6 KiB
C
Raw Normal View History

/*
* virtio ccw target definitions
*
* Copyright 2012,2015 IBM Corp.
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
* Pierre Morel <pmorel@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#ifndef HW_S390X_VIRTIO_CCW_H
#define HW_S390X_VIRTIO_CCW_H
#include "qom/object.h"
#include "hw/virtio/virtio-bus.h"
#include "hw/s390x/s390_flic.h"
#include "hw/s390x/css.h"
#include "ccw-device.h"
#include "hw/s390x/css-bridge.h"
#define VIRTIO_CCW_CU_TYPE 0x3832
#define VIRTIO_CCW_CHPID_TYPE 0x32
#define CCW_CMD_SET_VQ 0x13
#define CCW_CMD_VDEV_RESET 0x33
#define CCW_CMD_READ_FEAT 0x12
#define CCW_CMD_WRITE_FEAT 0x11
#define CCW_CMD_READ_CONF 0x22
#define CCW_CMD_WRITE_CONF 0x21
#define CCW_CMD_WRITE_STATUS 0x31
#define CCW_CMD_SET_IND 0x43
#define CCW_CMD_SET_CONF_IND 0x53
#define CCW_CMD_READ_VQ_CONF 0x32
#define CCW_CMD_READ_STATUS 0x72
#define CCW_CMD_SET_IND_ADAPTER 0x73
#define CCW_CMD_SET_VIRTIO_REV 0x83
#define TYPE_VIRTIO_CCW_DEVICE "virtio-ccw-device"
OBJECT_DECLARE_TYPE(VirtioCcwDevice, VirtIOCCWDeviceClass, VIRTIO_CCW_DEVICE)
typedef struct VirtioBusState VirtioCcwBusState;
typedef struct VirtioBusClass VirtioCcwBusClass;
#define TYPE_VIRTIO_CCW_BUS "virtio-ccw-bus"
DECLARE_OBJ_CHECKERS(VirtioCcwBusState, VirtioCcwBusClass,
VIRTIO_CCW_BUS, TYPE_VIRTIO_CCW_BUS)
/*
* modules can reference this symbol to avoid being loaded
* into system emulators without ccw support
*/
extern bool have_virtio_ccw;
struct VirtIOCCWDeviceClass {
CCWDeviceClass parent_class;
void (*realize)(VirtioCcwDevice *dev, Error **errp);
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
void (*unrealize)(VirtioCcwDevice *dev);
void (*parent_reset)(DeviceState *dev);
};
/* Performance improves when virtqueue kick processing is decoupled from the
* vcpu thread using ioeventfd for some devices. */
#define VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT 1
#define VIRTIO_CCW_FLAG_USE_IOEVENTFD (1 << VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT)
struct VirtioCcwDevice {
CcwDevice parent_obj;
int revision;
uint32_t max_rev;
VirtioBusState bus;
uint32_t flags;
uint8_t thinint_isc;
AdapterRoutes routes;
/* Guest provided values: */
IndAddr *indicators;
IndAddr *indicators2;
IndAddr *summary_indicator;
uint64_t ind_bit;
bool force_revision_1;
};
/* The maximum virtio revision we support. */
#define VIRTIO_CCW_MAX_REV 2
static inline int virtio_ccw_rev_max(VirtioCcwDevice *dev)
{
return dev->max_rev;
}
VirtIODevice *virtio_ccw_get_vdev(SubchDev *sch);
#endif