This patchs adds the skeleton for the virtio-iommu device.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
v9 -> v10:
- expose VIRTIO_IOMMU_F_MMIO feature
- s/domain_bits/domain_range struct
- change error codes
- enforce unmigratable
- Kconfig
v7 -> v8:
- expose VIRTIO_IOMMU_F_BYPASS and VIRTIO_F_VERSION_1
features
- set_config dummy implementation + tracing
- add trace in get_features
- set the features on realize() and store the acked ones
- remove inclusion of linux/virtio_iommu.h
v6 -> v7:
- removed qapi-event.h include
- add primary_bus and associated property
v4 -> v5:
- use the new v0.5 terminology (domain, endpoint)
- add the event virtqueue
v3 -> v4:
- use page_size_mask instead of page_sizes
- added set_features()
- added some traces (reset, set_status, set_features)
- empty virtio_iommu_set_config() as the driver MUST NOT
write to device configuration fields
- add get_config trace
v2 -> v3:
- rebase on 2.10-rc0, ie. use IOMMUMemoryRegion and remove
iommu_ops.
- advertise VIRTIO_IOMMU_F_MAP_UNMAP feature
- page_sizes set to TARGET_PAGE_SIZE
Conflicts:
hw/virtio/trace-events
---
hw/virtio/Kconfig | 5 +
hw/virtio/Makefile.objs | 1 +
hw/virtio/trace-events | 8 +
hw/virtio/virtio-iommu.c | 267 +++++++++++++++++++++++++++++++
include/hw/virtio/virtio-iommu.h | 62 +++++++
5 files changed, 343 insertions(+)
create mode 100644 hw/virtio/virtio-iommu.c
create mode 100644 include/hw/virtio/virtio-iommu.h
diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig
index 3724ff8bac..a30107b439 100644
--- a/hw/virtio/Kconfig
+++ b/hw/virtio/Kconfig
@@ -6,6 +6,11 @@ config VIRTIO_RNG
default y
depends on VIRTIO
+config VIRTIO_IOMMU
+ bool
+ default y
+ depends on VIRTIO
+
config VIRTIO_PCI
bool
default y if PCI_DEVICES
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 964ce78607..f42e4dd94f 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -14,6 +14,7 @@ obj-$(CONFIG_VIRTIO_CRYPTO) += virtio-crypto.o
obj-$(call land,$(CONFIG_VIRTIO_CRYPTO),$(CONFIG_VIRTIO_PCI)) += virtio-crypto-pci.o
obj-$(CONFIG_VIRTIO_PMEM) += virtio-pmem.o
common-obj-$(call land,$(CONFIG_VIRTIO_PMEM),$(CONFIG_VIRTIO_PCI)) += virtio-pmem-pci.o
+obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o
obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock.o
ifeq ($(CONFIG_VIRTIO_PCI),y)
diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index e28ba48da6..f7dac39213 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -53,3 +53,11 @@ virtio_mmio_write_offset(uint64_t offset, uint64_t value) "virtio_mmio_write off
virtio_mmio_guest_page(uint64_t size, int shift) "guest page size 0x%" PRIx64 " shift %d"
virtio_mmio_queue_write(uint64_t value, int max_size) "mmio_queue write 0x%" PRIx64 " max %d"
virtio_mmio_setting_irq(int level) "virtio_mmio setting IRQ %d"
+
+# hw/virtio/virtio-iommu.c
+virtio_iommu_device_reset(void) "reset!"
+virtio_iommu_get_features(uint64_t features) "device supports features=0x%"PRIx64
+virtio_iommu_set_features(uint64_t features) "features accepted by the driver =0x%"PRIx64
+virtio_iommu_device_status(uint8_t status) "driver status = %d"
+virtio_iommu_get_config(uint64_t page_size_mask, uint64_t start, uint64_t end, uint32_t domain_range, uint32_t probe_size) "page_size_mask=0x%"PRIx64" start=0x%"PRIx64" end=0x%"PRIx64" domain_range=%d probe_size=0x%x"
+virtio_iommu_set_config(uint64_t page_size_mask, uint64_t start, uint64_t end, uint32_t domain_range, uint32_t probe_size) "page_size_mask=0x%"PRIx64" start=0x%"PRIx64" end=0x%"PRIx64" domain_bits=%d probe_size=0x%x"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
new file mode 100644
index 0000000000..f239954396
--- /dev/null
+++ b/hw/virtio/virtio-iommu.c
@@ -0,0 +1,267 @@
+/*
+ * virtio-iommu device
+ *
+ * Copyright (c) 2017 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/iov.h"
+#include "qemu-common.h"
+#include "hw/virtio/virtio.h"
+#include "sysemu/kvm.h"
+#include "trace.h"
+
+#include "standard-headers/linux/virtio_ids.h"
+
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/virtio-access.h"
+#include "hw/virtio/virtio-iommu.h"
+
+/* Max size */
+#define VIOMMU_DEFAULT_QUEUE_SIZE 256
+
+static int virtio_iommu_handle_attach(VirtIOIOMMU *s,
+ struct iovec *iov,
+ unsigned int iov_cnt)
+{
+ return VIRTIO_IOMMU_S_UNSUPP;
+}
+static int virtio_iommu_handle_detach(VirtIOIOMMU *s,
+ struct iovec *iov,
+ unsigned int iov_cnt)
+{
+ return VIRTIO_IOMMU_S_UNSUPP;
+}
+static int virtio_iommu_handle_map(VirtIOIOMMU *s,
+ struct iovec *iov,
+ unsigned int iov_cnt)
+{
+ return VIRTIO_IOMMU_S_UNSUPP;
+}
+static int virtio_iommu_handle_unmap(VirtIOIOMMU *s,
+ struct iovec *iov,
+ unsigned int iov_cnt)
+{
+ return VIRTIO_IOMMU_S_UNSUPP;
+}
+
+static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq)
+{
+ VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
+ struct virtio_iommu_req_head head;
+ struct virtio_iommu_req_tail tail;
+ VirtQueueElement *elem;
+ unsigned int iov_cnt;
+ struct iovec *iov;
+ size_t sz;
+
+ for (;;) {
+ elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
+ if (!elem) {
+ return;
+ }
+
+ if (iov_size(elem->in_sg, elem->in_num) < sizeof(tail) ||
+ iov_size(elem->out_sg, elem->out_num) < sizeof(head)) {
+ virtio_error(vdev, "virtio-iommu bad head/tail size");
+ virtqueue_detach_element(vq, elem, 0);
+ g_free(elem);
+ break;
+ }
+
+ iov_cnt = elem->out_num;
+ iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
+ sz = iov_to_buf(iov, iov_cnt, 0, &head, sizeof(head));
+ if (unlikely(sz != sizeof(head))) {
+ tail.status = VIRTIO_IOMMU_S_DEVERR;
+ goto out;
+ }
+ qemu_mutex_lock(&s->mutex);
+ switch (head.type) {
+ case VIRTIO_IOMMU_T_ATTACH:
+ tail.status = virtio_iommu_handle_attach(s, iov, iov_cnt);
+ break;
+ case VIRTIO_IOMMU_T_DETACH:
+ tail.status = virtio_iommu_handle_detach(s, iov, iov_cnt);
+ break;
+ case VIRTIO_IOMMU_T_MAP:
+ tail.status = virtio_iommu_handle_map(s, iov, iov_cnt);
+ break;
+ case VIRTIO_IOMMU_T_UNMAP:
+ tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt);
+ break;
+ default:
+ tail.status = VIRTIO_IOMMU_S_UNSUPP;
+ }
+ qemu_mutex_unlock(&s->mutex);
+
+out:
+ sz = iov_from_buf(elem->in_sg, elem->in_num, 0,
+ &tail, sizeof(tail));
+ assert(sz == sizeof(tail));
+
+ virtqueue_push(vq, elem, sizeof(tail));
+ virtio_notify(vdev, vq);
+ g_free(elem);
+ }
+}
+
+static void virtio_iommu_get_config(VirtIODevice *vdev, uint8_t *config_data)
+{
+ VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
+ struct virtio_iommu_config *config = &dev->config;
+
+ trace_virtio_iommu_get_config(config->page_size_mask,
+ config->input_range.start,
+ config->input_range.end,
+ config->domain_range.end,
+ config->probe_size);
+ memcpy(config_data, &dev->config, sizeof(struct virtio_iommu_config));
+}
+
+static void virtio_iommu_set_config(VirtIODevice *vdev,
+ const uint8_t *config_data)
+{
+ struct virtio_iommu_config config;
+
+ memcpy(&config, config_data, sizeof(struct virtio_iommu_config));
+ trace_virtio_iommu_set_config(config.page_size_mask,
+ config.input_range.start,
+ config.input_range.end,
+ config.domain_range.end,
+ config.probe_size);
+}
+
+static uint64_t virtio_iommu_get_features(VirtIODevice *vdev, uint64_t f,
+ Error **errp)
+{
+ VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
+
+ f |= dev->features;
+ trace_virtio_iommu_get_features(f);
+ return f;
+}
+
+static void virtio_iommu_set_features(VirtIODevice *vdev, uint64_t val)
+{
+ VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
+
+ dev->acked_features = val;
+ trace_virtio_iommu_set_features(dev->acked_features);
+}
+
+static const VMStateDescription vmstate_virtio_iommu_device = {
+ .name = "virtio-iommu-device",
+ .unmigratable = 1,
+};
+
+static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
+
+ virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
+ sizeof(struct virtio_iommu_config));
+
+ s->req_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE,
+ virtio_iommu_handle_command);
+ s->event_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE, NULL);
+
+ s->config.page_size_mask = TARGET_PAGE_MASK;
+ s->config.input_range.end = -1UL;
+ s->config.domain_range.start = 0;
+ s->config.domain_range.end = 32;
+
+ virtio_add_feature(&s->features, VIRTIO_RING_F_EVENT_IDX);
+ virtio_add_feature(&s->features, VIRTIO_RING_F_INDIRECT_DESC);
+ virtio_add_feature(&s->features, VIRTIO_F_VERSION_1);
+ virtio_add_feature(&s->features, VIRTIO_IOMMU_F_INPUT_RANGE);
+ virtio_add_feature(&s->features, VIRTIO_IOMMU_F_DOMAIN_RANGE);
+ virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
+ virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
+ virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
+}
+
+static void virtio_iommu_device_unrealize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+
+ virtio_cleanup(vdev);
+}
+
+static void virtio_iommu_device_reset(VirtIODevice *vdev)
+{
+ trace_virtio_iommu_device_reset();
+}
+
+static void virtio_iommu_set_status(VirtIODevice *vdev, uint8_t status)
+{
+ trace_virtio_iommu_device_status(status);
+}
+
+static void virtio_iommu_instance_init(Object *obj)
+{
+}
+
+static const VMStateDescription vmstate_virtio_iommu = {
+ .name = "virtio-iommu",
+ .minimum_version_id = 1,
+ .version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_VIRTIO_DEVICE,
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static Property virtio_iommu_properties[] = {
+ DEFINE_PROP_LINK("primary-bus", VirtIOIOMMU, primary_bus, "PCI", PCIBus *),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_iommu_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+ dc->props = virtio_iommu_properties;
+ dc->vmsd = &vmstate_virtio_iommu;
+
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ vdc->realize = virtio_iommu_device_realize;
+ vdc->unrealize = virtio_iommu_device_unrealize;
+ vdc->reset = virtio_iommu_device_reset;
+ vdc->get_config = virtio_iommu_get_config;
+ vdc->set_config = virtio_iommu_set_config;
+ vdc->get_features = virtio_iommu_get_features;
+ vdc->set_features = virtio_iommu_set_features;
+ vdc->set_status = virtio_iommu_set_status;
+ vdc->vmsd = &vmstate_virtio_iommu_device;
+}
+
+static const TypeInfo virtio_iommu_info = {
+ .name = TYPE_VIRTIO_IOMMU,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VirtIOIOMMU),
+ .instance_init = virtio_iommu_instance_init,
+ .class_init = virtio_iommu_class_init,
+};
+
+static void virtio_register_types(void)
+{
+ type_register_static(&virtio_iommu_info);
+}
+
+type_init(virtio_register_types)
diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h
new file mode 100644
index 0000000000..4d47b6abeb
--- /dev/null
+++ b/include/hw/virtio/virtio-iommu.h
@@ -0,0 +1,62 @@
+/*
+ * virtio-iommu device
+ *
+ * Copyright (c) 2017 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef QEMU_VIRTIO_IOMMU_H
+#define QEMU_VIRTIO_IOMMU_H
+
+#include "standard-headers/linux/virtio_iommu.h"
+#include "hw/virtio/virtio.h"
+#include "hw/pci/pci.h"
+
+#define TYPE_VIRTIO_IOMMU "virtio-iommu-device"
+#define VIRTIO_IOMMU(obj) \
+ OBJECT_CHECK(VirtIOIOMMU, (obj), TYPE_VIRTIO_IOMMU)
+
+#define IOMMU_PCI_BUS_MAX 256
+#define IOMMU_PCI_DEVFN_MAX 256
+
+typedef struct IOMMUDevice {
+ void *viommu;
+ PCIBus *bus;
+ int devfn;
+ IOMMUMemoryRegion iommu_mr;
+ AddressSpace as;
+} IOMMUDevice;
+
+typedef struct IOMMUPciBus {
+ PCIBus *bus;
+ IOMMUDevice *pbdev[0]; /* Parent array is sparse, so dynamically alloc */
+} IOMMUPciBus;
+
+typedef struct VirtIOIOMMU {
+ VirtIODevice parent_obj;
+ VirtQueue *req_vq;
+ VirtQueue *event_vq;
+ struct virtio_iommu_config config;
+ uint64_t features;
+ uint64_t acked_features;
+ GHashTable *as_by_busptr;
+ IOMMUPciBus *as_by_bus_num[IOMMU_PCI_BUS_MAX];
+ PCIBus *primary_bus;
+ GTree *domains;
+ QemuMutex mutex;
+ GTree *endpoints;
+} VirtIOIOMMU;
+
+#endif
--
2.20.1
On Tue, Jul 30, 2019 at 07:21:25PM +0200, Eric Auger wrote:
> +static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq)
> +{
> + VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
> + struct virtio_iommu_req_head head;
> + struct virtio_iommu_req_tail tail;
[1]
> + VirtQueueElement *elem;
> + unsigned int iov_cnt;
> + struct iovec *iov;
> + size_t sz;
> +
> + for (;;) {
> + elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
> + if (!elem) {
> + return;
> + }
> +
> + if (iov_size(elem->in_sg, elem->in_num) < sizeof(tail) ||
> + iov_size(elem->out_sg, elem->out_num) < sizeof(head)) {
> + virtio_error(vdev, "virtio-iommu bad head/tail size");
> + virtqueue_detach_element(vq, elem, 0);
> + g_free(elem);
> + break;
> + }
> +
> + iov_cnt = elem->out_num;
> + iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
Could I ask why memdup is needed here?
> + sz = iov_to_buf(iov, iov_cnt, 0, &head, sizeof(head));
> + if (unlikely(sz != sizeof(head))) {
> + tail.status = VIRTIO_IOMMU_S_DEVERR;
Do you need to zero the reserved bits to make sure it won't contain
garbage? Same question to below uses of tail.
> + goto out;
> + }
> + qemu_mutex_lock(&s->mutex);
> + switch (head.type) {
> + case VIRTIO_IOMMU_T_ATTACH:
> + tail.status = virtio_iommu_handle_attach(s, iov, iov_cnt);
> + break;
> + case VIRTIO_IOMMU_T_DETACH:
> + tail.status = virtio_iommu_handle_detach(s, iov, iov_cnt);
> + break;
> + case VIRTIO_IOMMU_T_MAP:
> + tail.status = virtio_iommu_handle_map(s, iov, iov_cnt);
> + break;
> + case VIRTIO_IOMMU_T_UNMAP:
> + tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt);
> + break;
> + default:
> + tail.status = VIRTIO_IOMMU_S_UNSUPP;
> + }
> + qemu_mutex_unlock(&s->mutex);
> +
> +out:
> + sz = iov_from_buf(elem->in_sg, elem->in_num, 0,
> + &tail, sizeof(tail));
> + assert(sz == sizeof(tail));
> +
> + virtqueue_push(vq, elem, sizeof(tail));
s/tail/head/ (though they are the same size)?
> + virtio_notify(vdev, vq);
> + g_free(elem);
> + }
> +}
[...]
> +static void virtio_iommu_set_features(VirtIODevice *vdev, uint64_t val)
> +{
> + VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
> +
> + dev->acked_features = val;
> + trace_virtio_iommu_set_features(dev->acked_features);
> +}
> +
> +static const VMStateDescription vmstate_virtio_iommu_device = {
> + .name = "virtio-iommu-device",
> + .unmigratable = 1,
Curious, is there explicit reason to not support migration from the
first version? :)
> +};
> +
> +static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
> +{
> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> + VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
> +
> + virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
> + sizeof(struct virtio_iommu_config));
> +
> + s->req_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE,
> + virtio_iommu_handle_command);
> + s->event_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE, NULL);
> +
> + s->config.page_size_mask = TARGET_PAGE_MASK;
> + s->config.input_range.end = -1UL;
> + s->config.domain_range.start = 0;
Zero input_range.start = 0? After all domain_range.start is zeroed.
> + s->config.domain_range.end = 32;
> +
> + virtio_add_feature(&s->features, VIRTIO_RING_F_EVENT_IDX);
> + virtio_add_feature(&s->features, VIRTIO_RING_F_INDIRECT_DESC);
> + virtio_add_feature(&s->features, VIRTIO_F_VERSION_1);
> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_INPUT_RANGE);
> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_DOMAIN_RANGE);
> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
> +}
Regards,
--
Peter Xu
Hi Peter,
First of all, please forgive me for the delay.
On 8/15/19 3:54 PM, Peter Xu wrote:
> On Tue, Jul 30, 2019 at 07:21:25PM +0200, Eric Auger wrote:
>> +static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq)
>> +{
>> + VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
>> + struct virtio_iommu_req_head head;
>> + struct virtio_iommu_req_tail tail;
>
> [1]
>
>> + VirtQueueElement *elem;
>> + unsigned int iov_cnt;
>> + struct iovec *iov;
>> + size_t sz;
>> +
>> + for (;;) {
>> + elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
>> + if (!elem) {
>> + return;
>> + }
>> +
>> + if (iov_size(elem->in_sg, elem->in_num) < sizeof(tail) ||
>> + iov_size(elem->out_sg, elem->out_num) < sizeof(head)) {
>> + virtio_error(vdev, "virtio-iommu bad head/tail size");
>> + virtqueue_detach_element(vq, elem, 0);
>> + g_free(elem);
>> + break;
>> + }
>> +
>> + iov_cnt = elem->out_num;
>> + iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
>
> Could I ask why memdup is needed here?
Indeed I don't think it is needed and besides iov is not freed!
I got inspired from hw/net/virtio-net.c. To be honest I don't get why
the g_memdup is needed there either. The out_sg gets duplicated and
commands work on the duplicated data and not in place.
>
>> + sz = iov_to_buf(iov, iov_cnt, 0, &head, sizeof(head));
>> + if (unlikely(sz != sizeof(head))) {
>> + tail.status = VIRTIO_IOMMU_S_DEVERR;
>
> Do you need to zero the reserved bits to make sure it won't contain
> garbage? Same question to below uses of tail.
yes. I initialized tail.
>
>> + goto out;
>> + }
>> + qemu_mutex_lock(&s->mutex);
>> + switch (head.type) {
>> + case VIRTIO_IOMMU_T_ATTACH:
>> + tail.status = virtio_iommu_handle_attach(s, iov, iov_cnt);
>> + break;
>> + case VIRTIO_IOMMU_T_DETACH:
>> + tail.status = virtio_iommu_handle_detach(s, iov, iov_cnt);
>> + break;
>> + case VIRTIO_IOMMU_T_MAP:
>> + tail.status = virtio_iommu_handle_map(s, iov, iov_cnt);
>> + break;
>> + case VIRTIO_IOMMU_T_UNMAP:
>> + tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt);
>> + break;
>> + default:
>> + tail.status = VIRTIO_IOMMU_S_UNSUPP;
>> + }
>> + qemu_mutex_unlock(&s->mutex);
>> +
>> +out:
>> + sz = iov_from_buf(elem->in_sg, elem->in_num, 0,
>> + &tail, sizeof(tail));
>> + assert(sz == sizeof(tail));
>> +
>> + virtqueue_push(vq, elem, sizeof(tail));
>
> s/tail/head/ (though they are the same size)?
That's unclear to me. Similarly when checking against virtio-net.c, the
element is pushed back to the used ring and len is set to the size of
the status with:
/*
* Control virtqueue data structures
*
* The control virtqueue expects a header in the first sg entry
* and an ack/status response in the last entry. Data for the
* command goes in between.
*/
>
>> + virtio_notify(vdev, vq);
>> + g_free(elem);
>> + }
>> +}
>
> [...]
>
>> +static void virtio_iommu_set_features(VirtIODevice *vdev, uint64_t val)
>> +{
>> + VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
>> +
>> + dev->acked_features = val;
>> + trace_virtio_iommu_set_features(dev->acked_features);
>> +}
>> +
>> +static const VMStateDescription vmstate_virtio_iommu_device = {
>> + .name = "virtio-iommu-device",
>> + .unmigratable = 1,
>
> Curious, is there explicit reason to not support migration from the
> first version? :)
The state is made of red black trees, lists. For the former there is no
VMSTATE* ready. I am working on it but I think this should be handled
separately
>
>> +};
>> +
>> +static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
>> +{
>> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
>> + VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
>> +
>> + virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
>> + sizeof(struct virtio_iommu_config));
>> +
>> + s->req_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE,
>> + virtio_iommu_handle_command);
>> + s->event_vq = virtio_add_queue(vdev, VIOMMU_DEFAULT_QUEUE_SIZE, NULL);
>> +
>> + s->config.page_size_mask = TARGET_PAGE_MASK;
>> + s->config.input_range.end = -1UL;
>> + s->config.domain_range.start = 0;
>
> Zero input_range.start = 0? After all domain_range.start is zeroed.
virtio_init does:
if (vdev->config_len) {
vdev->config = g_malloc0(config_size);
but I should be homogeneous and then remove s->config.domain_range.start
= 0;
>
>> + s->config.domain_range.end = 32;
>> +
>> + virtio_add_feature(&s->features, VIRTIO_RING_F_EVENT_IDX);
>> + virtio_add_feature(&s->features, VIRTIO_RING_F_INDIRECT_DESC);
>> + virtio_add_feature(&s->features, VIRTIO_F_VERSION_1);
>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_INPUT_RANGE);
>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_DOMAIN_RANGE);
>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP);
>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS);
>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO);
>> +}
>
> Regards,
>
On Thu, Aug 29, 2019 at 02:18:42PM +0200, Auger Eric wrote:
> Hi Peter,
>
> First of all, please forgive me for the delay.
> On 8/15/19 3:54 PM, Peter Xu wrote:
> > On Tue, Jul 30, 2019 at 07:21:25PM +0200, Eric Auger wrote:
> >> +static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq)
> >> +{
> >> + VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
> >> + struct virtio_iommu_req_head head;
> >> + struct virtio_iommu_req_tail tail;
> >
> > [1]
> >
> >> + VirtQueueElement *elem;
> >> + unsigned int iov_cnt;
> >> + struct iovec *iov;
> >> + size_t sz;
> >> +
> >> + for (;;) {
> >> + elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
> >> + if (!elem) {
> >> + return;
> >> + }
> >> +
> >> + if (iov_size(elem->in_sg, elem->in_num) < sizeof(tail) ||
> >> + iov_size(elem->out_sg, elem->out_num) < sizeof(head)) {
> >> + virtio_error(vdev, "virtio-iommu bad head/tail size");
> >> + virtqueue_detach_element(vq, elem, 0);
> >> + g_free(elem);
> >> + break;
> >> + }
> >> +
> >> + iov_cnt = elem->out_num;
> >> + iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
> >
> > Could I ask why memdup is needed here?
> Indeed I don't think it is needed and besides iov is not freed!
>
> I got inspired from hw/net/virtio-net.c. To be honest I don't get why
> the g_memdup is needed there either. The out_sg gets duplicated and
> commands work on the duplicated data and not in place.
Oh true, I found that it's because of calling of iov_discard_front().
Please have a look at 771b6ed37e3. Though it seems to me that
virtio-iommu does not truncate iovs so it should not be needed.
> >
> >> + sz = iov_to_buf(iov, iov_cnt, 0, &head, sizeof(head));
> >> + if (unlikely(sz != sizeof(head))) {
> >> + tail.status = VIRTIO_IOMMU_S_DEVERR;
> >
> > Do you need to zero the reserved bits to make sure it won't contain
> > garbage? Same question to below uses of tail.
> yes. I initialized tail.
> >
> >> + goto out;
> >> + }
> >> + qemu_mutex_lock(&s->mutex);
> >> + switch (head.type) {
> >> + case VIRTIO_IOMMU_T_ATTACH:
> >> + tail.status = virtio_iommu_handle_attach(s, iov, iov_cnt);
> >> + break;
> >> + case VIRTIO_IOMMU_T_DETACH:
> >> + tail.status = virtio_iommu_handle_detach(s, iov, iov_cnt);
> >> + break;
> >> + case VIRTIO_IOMMU_T_MAP:
> >> + tail.status = virtio_iommu_handle_map(s, iov, iov_cnt);
> >> + break;
> >> + case VIRTIO_IOMMU_T_UNMAP:
> >> + tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt);
> >> + break;
> >> + default:
> >> + tail.status = VIRTIO_IOMMU_S_UNSUPP;
> >> + }
> >> + qemu_mutex_unlock(&s->mutex);
> >> +
> >> +out:
> >> + sz = iov_from_buf(elem->in_sg, elem->in_num, 0,
> >> + &tail, sizeof(tail));
> >> + assert(sz == sizeof(tail));
> >> +
> >> + virtqueue_push(vq, elem, sizeof(tail));
> >
> > s/tail/head/ (though they are the same size)?
> That's unclear to me. Similarly when checking against virtio-net.c, the
> element is pushed back to the used ring and len is set to the size of
> the status with:
>
> /*
> * Control virtqueue data structures
> *
> * The control virtqueue expects a header in the first sg entry
> * and an ack/status response in the last entry. Data for the
> * command goes in between.
> */
I was referencing the balloon code when reading the patch, e.g.,
virtio_balloon_handle_output(). Though after I read more carefully I
see that other places are using it as you described. Now I tend to
agree with you, because virtqueue_push() who calls
virtqueue_unmap_sg() used the len to unmap in_sg[] rather than
out_sg[]. So please ignore my previous comment.
(then I'm not sure whether the usage in the balloon code was correct
now...)
> >
> >> + virtio_notify(vdev, vq);
> >> + g_free(elem);
> >> + }
> >> +}
> >
> > [...]
> >
> >> +static void virtio_iommu_set_features(VirtIODevice *vdev, uint64_t val)
> >> +{
> >> + VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
> >> +
> >> + dev->acked_features = val;
> >> + trace_virtio_iommu_set_features(dev->acked_features);
> >> +}
> >> +
> >> +static const VMStateDescription vmstate_virtio_iommu_device = {
> >> + .name = "virtio-iommu-device",
> >> + .unmigratable = 1,
> >
> > Curious, is there explicit reason to not support migration from the
> > first version? :)
> The state is made of red black trees, lists. For the former there is no
> VMSTATE* ready. I am working on it but I think this should be handled
> separately
Fair enough. Would you mind to add a similar comment above
unmigratable?
Thanks,
--
Peter Xu
Hi Peter,
On 8/30/19 3:26 AM, Peter Xu wrote:
> On Thu, Aug 29, 2019 at 02:18:42PM +0200, Auger Eric wrote:
>> Hi Peter,
>>
>> First of all, please forgive me for the delay.
>> On 8/15/19 3:54 PM, Peter Xu wrote:
>>> On Tue, Jul 30, 2019 at 07:21:25PM +0200, Eric Auger wrote:
>>>> +static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq)
>>>> +{
>>>> + VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
>>>> + struct virtio_iommu_req_head head;
>>>> + struct virtio_iommu_req_tail tail;
>>>
>>> [1]
>>>
>>>> + VirtQueueElement *elem;
>>>> + unsigned int iov_cnt;
>>>> + struct iovec *iov;
>>>> + size_t sz;
>>>> +
>>>> + for (;;) {
>>>> + elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
>>>> + if (!elem) {
>>>> + return;
>>>> + }
>>>> +
>>>> + if (iov_size(elem->in_sg, elem->in_num) < sizeof(tail) ||
>>>> + iov_size(elem->out_sg, elem->out_num) < sizeof(head)) {
>>>> + virtio_error(vdev, "virtio-iommu bad head/tail size");
>>>> + virtqueue_detach_element(vq, elem, 0);
>>>> + g_free(elem);
>>>> + break;
>>>> + }
>>>> +
>>>> + iov_cnt = elem->out_num;
>>>> + iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
>>>
>>> Could I ask why memdup is needed here?
>> Indeed I don't think it is needed and besides iov is not freed!
>>
>> I got inspired from hw/net/virtio-net.c. To be honest I don't get why
>> the g_memdup is needed there either. The out_sg gets duplicated and
>> commands work on the duplicated data and not in place.
>
> Oh true, I found that it's because of calling of iov_discard_front().
> Please have a look at 771b6ed37e3. Though it seems to me that
> virtio-iommu does not truncate iovs so it should not be needed.
thanks for the sha1. indeed virtio-iommu does not use iov_discard_front
so I shouldn't need it.
>
>>>
>>>> + sz = iov_to_buf(iov, iov_cnt, 0, &head, sizeof(head));
>>>> + if (unlikely(sz != sizeof(head))) {
>>>> + tail.status = VIRTIO_IOMMU_S_DEVERR;
>>>
>>> Do you need to zero the reserved bits to make sure it won't contain
>>> garbage? Same question to below uses of tail.
>> yes. I initialized tail.
>>>
>>>> + goto out;
>>>> + }
>>>> + qemu_mutex_lock(&s->mutex);
>>>> + switch (head.type) {
>>>> + case VIRTIO_IOMMU_T_ATTACH:
>>>> + tail.status = virtio_iommu_handle_attach(s, iov, iov_cnt);
>>>> + break;
>>>> + case VIRTIO_IOMMU_T_DETACH:
>>>> + tail.status = virtio_iommu_handle_detach(s, iov, iov_cnt);
>>>> + break;
>>>> + case VIRTIO_IOMMU_T_MAP:
>>>> + tail.status = virtio_iommu_handle_map(s, iov, iov_cnt);
>>>> + break;
>>>> + case VIRTIO_IOMMU_T_UNMAP:
>>>> + tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt);
>>>> + break;
>>>> + default:
>>>> + tail.status = VIRTIO_IOMMU_S_UNSUPP;
>>>> + }
>>>> + qemu_mutex_unlock(&s->mutex);
>>>> +
>>>> +out:
>>>> + sz = iov_from_buf(elem->in_sg, elem->in_num, 0,
>>>> + &tail, sizeof(tail));
>>>> + assert(sz == sizeof(tail));
>>>> +
>>>> + virtqueue_push(vq, elem, sizeof(tail));
>>>
>>> s/tail/head/ (though they are the same size)?
>> That's unclear to me. Similarly when checking against virtio-net.c, the
>> element is pushed back to the used ring and len is set to the size of
>> the status with:
>>
>> /*
>> * Control virtqueue data structures
>> *
>> * The control virtqueue expects a header in the first sg entry
>> * and an ack/status response in the last entry. Data for the
>> * command goes in between.
>> */
>
> I was referencing the balloon code when reading the patch, e.g.,
> virtio_balloon_handle_output(). Though after I read more carefully I
> see that other places are using it as you described. Now I tend to
> agree with you, because virtqueue_push() who calls
> virtqueue_unmap_sg() used the len to unmap in_sg[] rather than
> out_sg[]. So please ignore my previous comment.
OK
>
> (then I'm not sure whether the usage in the balloon code was correct
> now...)
>
>>>
>>>> + virtio_notify(vdev, vq);
>>>> + g_free(elem);
>>>> + }
>>>> +}
>>>
>>> [...]
>>>
>>>> +static void virtio_iommu_set_features(VirtIODevice *vdev, uint64_t val)
>>>> +{
>>>> + VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev);
>>>> +
>>>> + dev->acked_features = val;
>>>> + trace_virtio_iommu_set_features(dev->acked_features);
>>>> +}
>>>> +
>>>> +static const VMStateDescription vmstate_virtio_iommu_device = {
>>>> + .name = "virtio-iommu-device",
>>>> + .unmigratable = 1,
>>>
>>> Curious, is there explicit reason to not support migration from the
>>> first version? :)
>> The state is made of red black trees, lists. For the former there is no
>> VMSTATE* ready. I am working on it but I think this should be handled
>> separately
>
> Fair enough. Would you mind to add a similar comment above
> unmigratable?
sure
Thanks!
Eric
>
> Thanks,
>
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