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virtio-pci: convert to ioeventfd callbacks
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Convert to new interface.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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@cohuck @mstsirkin
cohuck authored and mstsirkin committed Jun 24, 2016
1 parent 7c55f68 commit 9f06e71
Showing 1 changed file with 41 additions and 83 deletions.
124 changes: 41 additions & 83 deletions hw/virtio/virtio-pci.c
View file
Expand Up @@ -262,14 +262,44 @@ static int virtio_pci_load_queue(DeviceState *d, int n, QEMUFile *f)
return 0;
}

static bool virtio_pci_ioeventfd_started(DeviceState *d)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);

return proxy->ioeventfd_started;
}

static void virtio_pci_ioeventfd_set_started(DeviceState *d, bool started,
bool err)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);

proxy->ioeventfd_started = started;
}

static bool virtio_pci_ioeventfd_disabled(DeviceState *d)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);

return proxy->ioeventfd_disabled ||
!(proxy->flags & VIRTIO_PCI_FLAG_USE_IOEVENTFD);
}

static void virtio_pci_ioeventfd_set_disabled(DeviceState *d, bool disabled)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);

proxy->ioeventfd_disabled = disabled;
}

#define QEMU_VIRTIO_PCI_QUEUE_MEM_MULT 0x1000

static int virtio_pci_set_host_notifier_internal(VirtIOPCIProxy *proxy,
int n, bool assign, bool set_handler)
static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier *notifier,
int n, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_get_queue(vdev, n);
EventNotifier *notifier = virtio_queue_get_host_notifier(vq);
bool legacy = !(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_LEGACY);
bool modern = !(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_MODERN);
bool fast_mmio = kvm_ioeventfd_any_length_enabled();
Expand All @@ -280,16 +310,8 @@ static int virtio_pci_set_host_notifier_internal(VirtIOPCIProxy *proxy,
hwaddr modern_addr = QEMU_VIRTIO_PCI_QUEUE_MEM_MULT *
virtio_get_queue_index(vq);
hwaddr legacy_addr = VIRTIO_PCI_QUEUE_NOTIFY;
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);
if (modern) {
if (fast_mmio) {
memory_region_add_eventfd(modern_mr, modern_addr, 0,
Expand Down Expand Up @@ -325,68 +347,18 @@ static int virtio_pci_set_host_notifier_internal(VirtIOPCIProxy *proxy,
memory_region_del_eventfd(legacy_mr, legacy_addr, 2,
true, n, notifier);
}
virtio_queue_set_host_notifier_fd_handler(vq, false, false);
event_notifier_cleanup(notifier);
}
return r;
return 0;
}

static void virtio_pci_start_ioeventfd(VirtIOPCIProxy *proxy)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
int n, r;

if (!(proxy->flags & VIRTIO_PCI_FLAG_USE_IOEVENTFD) ||
proxy->ioeventfd_disabled ||
proxy->ioeventfd_started) {
return;
}

for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}

r = virtio_pci_set_host_notifier_internal(proxy, n, true, true);
if (r < 0) {
goto assign_error;
}
}
proxy->ioeventfd_started = true;
return;

assign_error:
while (--n >= 0) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}

r = virtio_pci_set_host_notifier_internal(proxy, n, false, false);
assert(r >= 0);
}
proxy->ioeventfd_started = false;
error_report("%s: failed. Fallback to a userspace (slower).", __func__);
virtio_bus_start_ioeventfd(&proxy->bus);
}

static void virtio_pci_stop_ioeventfd(VirtIOPCIProxy *proxy)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
int r;
int n;

if (!proxy->ioeventfd_started) {
return;
}

for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}

r = virtio_pci_set_host_notifier_internal(proxy, n, false, false);
assert(r >= 0);
}
proxy->ioeventfd_started = false;
virtio_bus_stop_ioeventfd(&proxy->bus);
}

static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val)
Expand Down Expand Up @@ -1110,24 +1082,6 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
return r;
}

static int virtio_pci_set_host_notifier(DeviceState *d, int n, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);

/* Stop using ioeventfd for virtqueue kick if the device starts using host
* notifiers. This makes it easy to avoid stepping on each others' toes.
*/
proxy->ioeventfd_disabled = assign;
if (assign) {
virtio_pci_stop_ioeventfd(proxy);
}
/* We don't need to start here: it's not needed because backend
* currently only stops on status change away from ok,
* reset, vmstop and such. If we do add code to start here,
* need to check vmstate, device state etc. */
return virtio_pci_set_host_notifier_internal(proxy, n, assign, false);
}

static void virtio_pci_vmstate_change(DeviceState *d, bool running)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
Expand Down Expand Up @@ -2488,12 +2442,16 @@ static void virtio_pci_bus_class_init(ObjectClass *klass, void *data)
k->load_extra_state = virtio_pci_load_extra_state;
k->has_extra_state = virtio_pci_has_extra_state;
k->query_guest_notifiers = virtio_pci_query_guest_notifiers;
k->set_host_notifier = virtio_pci_set_host_notifier;
k->set_guest_notifiers = virtio_pci_set_guest_notifiers;
k->vmstate_change = virtio_pci_vmstate_change;
k->device_plugged = virtio_pci_device_plugged;
k->device_unplugged = virtio_pci_device_unplugged;
k->query_nvectors = virtio_pci_query_nvectors;
k->ioeventfd_started = virtio_pci_ioeventfd_started;
k->ioeventfd_set_started = virtio_pci_ioeventfd_set_started;
k->ioeventfd_disabled = virtio_pci_ioeventfd_disabled;
k->ioeventfd_set_disabled = virtio_pci_ioeventfd_set_disabled;
k->ioeventfd_assign = virtio_pci_ioeventfd_assign;
}

static const TypeInfo virtio_pci_bus_info = {
Expand Down

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