#include "qemu/osdep.h"
#include "hw/hw.h"
#include "qemu/error-report.h"
+#include "qemu/module.h"
+#include "qapi/error.h"
#include "hw/qdev.h"
#include "hw/virtio/virtio-bus.h"
#include "hw/virtio/virtio.h"
+#include "exec/address-spaces.h"
/* #define DEBUG_VIRTIO_BUS */
VirtioBusState *bus = VIRTIO_BUS(qbus);
VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus);
VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
+ bool has_iommu = virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
+ Error *local_err = NULL;
DPRINTF("%s: plug device.\n", qbus->name);
- if (klass->device_plugged != NULL) {
- klass->device_plugged(qbus->parent, errp);
+ if (klass->pre_plugged != NULL) {
+ klass->pre_plugged(qbus->parent, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
}
/* Get the features of the plugged device. */
assert(vdc->get_features != NULL);
vdev->host_features = vdc->get_features(vdev, vdev->host_features,
- errp);
- if (klass->post_plugged != NULL) {
- klass->post_plugged(qbus->parent, errp);
+ &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ if (klass->device_plugged != NULL) {
+ klass->device_plugged(qbus->parent, &local_err);
+ }
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ if (klass->get_dma_as != NULL && has_iommu) {
+ virtio_add_feature(&vdev->host_features, VIRTIO_F_IOMMU_PLATFORM);
+ vdev->dma_as = klass->get_dma_as(qbus->parent);
+ } else {
+ vdev->dma_as = &address_space_memory;
}
}
}
}
-/*
- * This function handles both assigning the ioeventfd handler and
- * registering it with the kernel.
- * assign: register/deregister ioeventfd with the kernel
- * set_handler: use the generic ioeventfd handler
- */
-static int set_host_notifier_internal(DeviceState *proxy, VirtioBusState *bus,
- int n, bool assign, bool set_handler)
+/* On success, ioeventfd ownership belongs to the caller. */
+int virtio_bus_grab_ioeventfd(VirtioBusState *bus)
{
- VirtIODevice *vdev = virtio_bus_get_device(bus);
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
- VirtQueue *vq = virtio_get_queue(vdev, n);
- EventNotifier *notifier = virtio_queue_get_host_notifier(vq);
- int r = 0;
- if (assign) {
- r = event_notifier_init(notifier, 1);
- if (r < 0) {
- error_report("%s: unable to init event notifier: %d", __func__, r);
- return r;
- }
- virtio_queue_set_host_notifier_fd_handler(vq, true, set_handler);
- r = k->ioeventfd_assign(proxy, notifier, n, assign);
- if (r < 0) {
- error_report("%s: unable to assign ioeventfd: %d", __func__, r);
- virtio_queue_set_host_notifier_fd_handler(vq, false, false);
- event_notifier_cleanup(notifier);
- return r;
- }
- } else {
- virtio_queue_set_host_notifier_fd_handler(vq, false, false);
- k->ioeventfd_assign(proxy, notifier, n, assign);
- event_notifier_cleanup(notifier);
+ /* vhost can be used even if ioeventfd=off in the proxy device,
+ * so do not check k->ioeventfd_enabled.
+ */
+ if (!k->ioeventfd_assign) {
+ return -ENOSYS;
+ }
+
+ if (bus->ioeventfd_grabbed == 0 && bus->ioeventfd_started) {
+ virtio_bus_stop_ioeventfd(bus);
+ /* Remember that we need to restart ioeventfd
+ * when ioeventfd_grabbed becomes zero.
+ */
+ bus->ioeventfd_started = true;
+ }
+ bus->ioeventfd_grabbed++;
+ return 0;
+}
+
+void virtio_bus_release_ioeventfd(VirtioBusState *bus)
+{
+ assert(bus->ioeventfd_grabbed != 0);
+ if (--bus->ioeventfd_grabbed == 0 && bus->ioeventfd_started) {
+ /* Force virtio_bus_start_ioeventfd to act. */
+ bus->ioeventfd_started = false;
+ virtio_bus_start_ioeventfd(bus);
}
- return r;
}
-void virtio_bus_start_ioeventfd(VirtioBusState *bus)
+int virtio_bus_start_ioeventfd(VirtioBusState *bus)
{
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
DeviceState *proxy = DEVICE(BUS(bus)->parent);
- VirtIODevice *vdev;
- int n, r;
+ VirtIODevice *vdev = virtio_bus_get_device(bus);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
+ int r;
- if (!k->ioeventfd_started || k->ioeventfd_started(proxy)) {
- return;
- }
- if (k->ioeventfd_disabled(proxy)) {
- return;
+ if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) {
+ return -ENOSYS;
}
- vdev = virtio_bus_get_device(bus);
- for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
- if (!virtio_queue_get_num(vdev, n)) {
- continue;
- }
- r = set_host_notifier_internal(proxy, bus, n, true, true);
- if (r < 0) {
- goto assign_error;
- }
+ if (bus->ioeventfd_started) {
+ return 0;
}
- k->ioeventfd_set_started(proxy, true, false);
- return;
-assign_error:
- while (--n >= 0) {
- if (!virtio_queue_get_num(vdev, n)) {
- continue;
+ /* Only set our notifier if we have ownership. */
+ if (!bus->ioeventfd_grabbed) {
+ r = vdc->start_ioeventfd(vdev);
+ if (r < 0) {
+ error_report("%s: failed. Fallback to userspace (slower).", __func__);
+ return r;
}
-
- r = set_host_notifier_internal(proxy, bus, n, false, false);
- assert(r >= 0);
}
- k->ioeventfd_set_started(proxy, false, true);
- error_report("%s: failed. Fallback to userspace (slower).", __func__);
+ bus->ioeventfd_started = true;
+ return 0;
}
void virtio_bus_stop_ioeventfd(VirtioBusState *bus)
{
- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
- DeviceState *proxy = DEVICE(BUS(bus)->parent);
VirtIODevice *vdev;
- int n, r;
+ VirtioDeviceClass *vdc;
- if (!k->ioeventfd_started || !k->ioeventfd_started(proxy)) {
+ if (!bus->ioeventfd_started) {
return;
}
- vdev = virtio_bus_get_device(bus);
- for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
- if (!virtio_queue_get_num(vdev, n)) {
- continue;
- }
- r = set_host_notifier_internal(proxy, bus, n, false, false);
- assert(r >= 0);
+
+ /* Only remove our notifier if we have ownership. */
+ if (!bus->ioeventfd_grabbed) {
+ vdev = virtio_bus_get_device(bus);
+ vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
+ vdc->stop_ioeventfd(vdev);
}
- k->ioeventfd_set_started(proxy, false, false);
+ bus->ioeventfd_started = false;
+}
+
+bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus)
+{
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
+ DeviceState *proxy = DEVICE(BUS(bus)->parent);
+
+ return k->ioeventfd_assign && k->ioeventfd_enabled(proxy);
}
/*
- * This function switches from/to the generic ioeventfd handler.
- * assign==false means 'use generic ioeventfd handler'.
+ * This function switches ioeventfd on/off in the device.
+ * The caller must set or clear the handlers for the EventNotifier.
*/
int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign)
{
+ VirtIODevice *vdev = virtio_bus_get_device(bus);
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
DeviceState *proxy = DEVICE(BUS(bus)->parent);
- VirtIODevice *vdev = virtio_bus_get_device(bus);
VirtQueue *vq = virtio_get_queue(vdev, n);
+ EventNotifier *notifier = virtio_queue_get_host_notifier(vq);
+ int r = 0;
- if (!k->ioeventfd_started) {
+ if (!k->ioeventfd_assign) {
return -ENOSYS;
}
+
if (assign) {
- /*
- * Stop using the generic ioeventfd, we are doing eventfd handling
- * ourselves below
- */
- k->ioeventfd_set_disabled(proxy, true);
+ r = event_notifier_init(notifier, 1);
+ if (r < 0) {
+ error_report("%s: unable to init event notifier: %s (%d)",
+ __func__, strerror(-r), r);
+ return r;
+ }
+ r = k->ioeventfd_assign(proxy, notifier, n, true);
+ if (r < 0) {
+ error_report("%s: unable to assign ioeventfd: %d", __func__, r);
+ virtio_bus_cleanup_host_notifier(bus, n);
+ }
+ } else {
+ k->ioeventfd_assign(proxy, notifier, n, false);
}
- /*
- * Just switch the handler, don't deassign the ioeventfd.
- * Otherwise, there's a window where we don't have an
- * ioeventfd and we may end up with a notification where
- * we don't expect one.
+
+ return r;
+}
+
+void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n)
+{
+ VirtIODevice *vdev = virtio_bus_get_device(bus);
+ VirtQueue *vq = virtio_get_queue(vdev, n);
+ EventNotifier *notifier = virtio_queue_get_host_notifier(vq);
+
+ /* Test and clear notifier after disabling event,
+ * in case poll callback didn't have time to run.
*/
- virtio_queue_set_host_notifier_fd_handler(vq, assign, !assign);
- if (!assign) {
- /* Use generic ioeventfd handler again. */
- k->ioeventfd_set_disabled(proxy, false);
- }
- return 0;
+ virtio_queue_host_notifier_read(notifier);
+ event_notifier_cleanup(notifier);
}
static char *virtio_bus_get_dev_path(DeviceState *dev)
projects / mirror_qemu.git / blobdiff