From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
The WWPN specified in configfs is passed to "-device vhost-scsi-pci".
The tgpt field of the SET_ENDPOINT ioctl is obsolete now, so it is not
available from the QEMU command-line. Instead, I hardcode it to zero.
Changes in V3:
- Drop ioeventfd vhost_scsi_properties (asias, thanks stefanha)
- Add CONFIG_VHOST_SCSI (asias, thanks stefanha)
- Add hotplug feature bit
Changes in V2:
- Add backend guest masking support (nab)
- Bump ABI_VERSION to 1 (nab)
- Set up set_guest_notifiers (asias)
- Set up vs->dev.vq_index (asias)
- Drop vs->vs.vdev.{set,clear}_vhost_endpoint (asias)
- Drop VIRTIO_CONFIG_S_DRIVER check in vhost_scsi_set_status (asias)
Howto:
Use the latest seabios
git clone git://git.seabios.org/seabios.git
make
cp out/bios.bin /usr/share/qemu/bios.bin
qemu -device vhost-scsi-pci,wwpn=naa.6001405bd4e8476d,event_idx=off ...
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Asias He <asias@xxxxxxxxxx>
---
configure | 15 ++-
hw/Makefile.objs | 5 +-
hw/s390x/s390-virtio-bus.c | 35 +++++++
hw/vhost-scsi.c | 242 +++++++++++++++++++++++++++++++++++++++++++++
hw/vhost-scsi.h | 65 ++++++++++++
hw/virtio-pci.c | 62 ++++++++++++
hw/virtio-scsi.h | 2 +
7 files changed, 424 insertions(+), 2 deletions(-)
create mode 100644 hw/vhost-scsi.c
create mode 100644 hw/vhost-scsi.h
diff --git a/configure b/configure
index 84317c6..dca4a66 100755
--- a/configure
+++ b/configure
@@ -169,6 +169,7 @@ libattr=""
xfs=""
vhost_net="no"
+vhost_scsi="no"
kvm="no"
gprof="no"
debug_tcg="no"
@@ -531,6 +532,7 @@ Haiku)
usb="linux"
kvm="yes"
vhost_net="yes"
+ vhost_scsi="yes"
if [ "$cpu" = "i386" -o "$cpu" = "x86_64" ] ; then
audio_possible_drivers="$audio_possible_drivers fmod"
fi
@@ -857,6 +859,10 @@ for opt do
;;
--enable-vhost-net) vhost_net="yes"
;;
+ --disable-vhost-scsi) vhost_scsi="no"
+ ;;
+ --enable-vhost-scsi) vhost_scsi="yes"
+ ;;
--disable-opengl) opengl="no"
;;
--enable-opengl) opengl="yes"
@@ -3058,7 +3064,7 @@ fi
# __sync_fetch_and_and requires at least -march=i486. Many toolchains
# use i686 as default anyway, but for those that don't, an explicit
# specification is necessary
-if test "$vhost_net" = "yes" && test "$cpu" = "i386"; then
+if (test "$vhost_net" = "yes" -o "$vhost_scsi" = "yes") && test "$cpu" = "i386"; then
cat > $TMPC << EOF
static int sfaa(int *ptr)
{
@@ -3404,6 +3410,7 @@ echo "sigev_thread_id $sigev_thread_id"
echo "uuid support $uuid"
echo "libcap-ng support $cap_ng"
echo "vhost-net support $vhost_net"
+echo "vhost-scsi support $vhost_scsi"
echo "Trace backend $trace_backend"
echo "Trace output file $trace_file-<pid>"
echo "spice support $spice ($spice_protocol_version/$spice_server_version)"
@@ -3673,6 +3680,9 @@ fi
if test "$virtfs" = "yes" ; then
echo "CONFIG_VIRTFS=y" >> $config_host_mak
fi
+if test "$vhost_scsi" = "yes" ; then
+ echo "CONFIG_VHOST_SCSI=y" >> $config_host_mak
+fi
if test "$blobs" = "yes" ; then
echo "INSTALL_BLOBS=yes" >> $config_host_mak
fi
@@ -4149,6 +4159,9 @@ case "$target_arch2" in
if test "$vhost_net" = "yes" ; then
echo "CONFIG_VHOST_NET=y" >> $config_target_mak
fi
+ if test "$vhost_scsi" = "yes" ; then
+ echo "CONFIG_VHOST_SCSI=y" >> $config_target_mak
+ fi
fi
esac
case "$target_arch2" in
diff --git a/hw/Makefile.objs b/hw/Makefile.objs
index eb7eb31..df57e1f 100644
--- a/hw/Makefile.objs
+++ b/hw/Makefile.objs
@@ -202,8 +202,11 @@ common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o xenfb.o xen_disk.o xen_nic.o
obj-$(CONFIG_VIRTIO) += dataplane/
obj-$(CONFIG_VIRTIO) += virtio.o virtio-blk.o virtio-balloon.o virtio-net.o
obj-$(CONFIG_VIRTIO) += virtio-serial-bus.o virtio-scsi.o
+ifeq ($(CONFIG_VIRTIO), y)
+obj-$(CONFIG_LINUX) += vhost-scsi.o
+endif
obj-$(CONFIG_SOFTMMU) += vhost_net.o
-obj-$(CONFIG_VHOST_NET) += vhost.o
+obj-$(CONFIG_LINUX) += vhost.o
obj-$(CONFIG_REALLY_VIRTFS) += 9pfs/
obj-$(CONFIG_VGA) += vga.o
diff --git a/hw/s390x/s390-virtio-bus.c b/hw/s390x/s390-virtio-bus.c
index d9b7f83..d86365b 100644
--- a/hw/s390x/s390-virtio-bus.c
+++ b/hw/s390x/s390-virtio-bus.c
@@ -28,6 +28,8 @@
#include "hw/virtio-rng.h"
#include "hw/virtio-serial.h"
#include "hw/virtio-net.h"
+#include "hw/virtio-scsi.h"
+#include "hw/vhost-scsi.h"
#include "hw/sysbus.h"
#include "sysemu/kvm.h"
@@ -207,6 +209,18 @@ static int s390_virtio_scsi_init(VirtIOS390Device *dev)
return s390_virtio_device_init(dev, vdev);
}
+static int s390_vhost_scsi_init(VirtIOS390Device *dev)
+{
+ VirtIODevice *vdev;
+
+ vdev = vhost_scsi_init((DeviceState *)dev, &dev->scsi);
+ if (!vdev) {
+ return -1;
+ }
+
+ return s390_virtio_device_init(dev, vdev);
+}
+
static int s390_virtio_rng_init(VirtIOS390Device *dev)
{
VirtIODevice *vdev;
@@ -534,6 +548,27 @@ static const TypeInfo virtio_s390_device_info = {
.abstract = true,
};
+static Property s390_vhost_scsi_properties[] = {
+ DEFINE_VIRTIO_SCSI_PROPERTIES(VirtIOS390Device, host_features, scsi),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void s390_vhost_scsi_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtIOS390DeviceClass *k = VIRTIO_S390_DEVICE_CLASS(klass);
+
+ k->init = s390_vhost_scsi_init;
+ dc->props = s390_vhost_scsi_properties;
+}
+
+static const TypeInfo s390_vhost_scsi = {
+ .name = "vhost-scsi-s390",
+ .parent = TYPE_VIRTIO_S390_DEVICE,
+ .instance_size = sizeof(VirtIOS390Device),
+ .class_init = s390_vhost_scsi_class_init,
+};
+
static Property s390_virtio_scsi_properties[] = {
DEFINE_VIRTIO_SCSI_PROPERTIES(VirtIOS390Device, host_features, scsi),
DEFINE_PROP_END_OF_LIST(),
diff --git a/hw/vhost-scsi.c b/hw/vhost-scsi.c
new file mode 100644
index 0000000..45762d7
--- /dev/null
+++ b/hw/vhost-scsi.c
@@ -0,0 +1,242 @@
+/*
+ * vhost_scsi host device
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefanha@xxxxxxxxxxxxxxxxxx>
+ *
+ * Changes for QEMU mainline + tcm_vhost kernel upstream:
+ * Nicholas Bellinger <nab@xxxxxxxxxxxxxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include <sys/ioctl.h>
+#include "config.h"
+#include "qemu/queue.h"
+#include "monitor/monitor.h"
+#include "migration/migration.h"
+#include "vhost-scsi.h"
+#include "vhost.h"
+#include "virtio-scsi.h"
+
+typedef struct VHostSCSI {
+ VirtIOSCSICommon vs;
+
+ Error *migration_blocker;
+
+ struct vhost_dev dev;
+} VHostSCSI;
+
+static int vhost_scsi_set_endpoint(VirtIODevice *vdev)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+ struct vhost_scsi_target backend;
+ int ret;
+
+ memset(&backend, 0, sizeof(backend));
+ pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->vs.conf->wwpn);
+ ret = ioctl(vs->dev.control, VHOST_SCSI_SET_ENDPOINT, &backend);
+ if (ret < 0) {
+ return -errno;
+ }
+ return 0;
+}
+
+static void vhost_scsi_clear_endpoint(VirtIODevice *vdev)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+ struct vhost_scsi_target backend;
+
+ memset(&backend, 0, sizeof(backend));
+ pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->vs.conf->wwpn);
+ ioctl(vs->dev.control, VHOST_SCSI_CLEAR_ENDPOINT, &backend);
+}
+
+static int vhost_scsi_start(VHostSCSI *vs, VirtIODevice *vdev)
+{
+ int ret, abi_version;
+
+ if (!vdev->binding->set_guest_notifiers) {
+ error_report("binding does not support guest notifiers");
+ return -ENOSYS;
+ }
+
+ ret = ioctl(vs->dev.control, VHOST_SCSI_GET_ABI_VERSION, &abi_version);
+ if (ret < 0) {
+ return -errno;
+ }
+ if (abi_version > VHOST_SCSI_ABI_VERSION) {
+ error_report("vhost-scsi: The running tcm_vhost kernel abi_version:"
+ " %d is greater than vhost_scsi userspace supports: %d, please"
+ " upgrade your version of QEMU\n", abi_version,
+ VHOST_SCSI_ABI_VERSION);
+ return -ENOSYS;
+ }
+
+ ret = vhost_dev_enable_notifiers(&vs->dev, vdev);
+ if (ret < 0) {
+ return ret;
+ }
+
+ ret = vhost_dev_start(&vs->dev, vdev);
+ if (ret < 0) {
+ error_report("Error start vhost dev");
+ goto err_notifiers;
+ }
+
+ ret = vhost_scsi_set_endpoint(vdev);
+ if (ret < 0) {
+ error_report("Error set vhost-scsi endpoint");
+ goto err_vhost_stop;
+ }
+
+ ret = vdev->binding->set_guest_notifiers(vdev->binding_opaque, vs->dev.nvqs, true);
+ if (ret < 0) {
+ error_report("Error binding guest notifier");
+ goto err_endpoint;
+ }
+ return ret;
+
+err_endpoint:
+ vhost_scsi_clear_endpoint(vdev);
+err_vhost_stop:
+ vhost_dev_stop(&vs->dev, vdev);
+err_notifiers:
+ vhost_dev_disable_notifiers(&vs->dev, vdev);
+ return ret;
+}
+
+static void vhost_scsi_stop(VHostSCSI *vs, VirtIODevice *vdev)
+{
+ int ret = 0;
+
+ if (!vdev->binding->set_guest_notifiers) {
+ ret = vdev->binding->set_guest_notifiers(vdev->binding_opaque,
+ vs->dev.nvqs, false);
+ if (ret < 0) {
+ error_report("vhost guest notifier cleanup failed: %d\n", ret);
+ }
+ }
+ assert(ret >= 0);
+
+ vhost_scsi_clear_endpoint(vdev);
+ vhost_dev_stop(&vs->dev, vdev);
+ vhost_dev_disable_notifiers(&vs->dev, vdev);
+}
+
+static void vhost_scsi_set_config(VirtIODevice *vdev,
+ const uint8_t *config)
+{
+ VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+
+ if ((uint32_t) ldl_raw(&scsiconf->sense_size) != vs->vs.sense_size ||
+ (uint32_t) ldl_raw(&scsiconf->cdb_size) != vs->vs.cdb_size) {
+ error_report("vhost-scsi does not support changing the sense data and CDB sizes");
+ exit(1);
+ }
+}
+
+static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+ bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK);
+
+ if (vs->dev.started == start) {
+ return;
+ }
+
+ if (start) {
+ int ret;
+
+ ret = vhost_scsi_start(vs, vdev);
+ if (ret < 0) {
+ error_report("virtio-scsi: unable to start vhost: %s\n",
+ strerror(-ret));
+
+ /* There is no userspace virtio-scsi fallback so exit */
+ exit(1);
+ }
+ } else {
+ vhost_scsi_stop(vs, vdev);
+ }
+}
+
+static void vhost_scsi_guest_notifier_mask(VirtIODevice *vdev, int idx,
+ bool mask)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+
+ vhost_virtqueue_mask(&vs->dev, vdev, idx, mask);
+}
+
+static bool vhost_scsi_guest_notifier_pending(VirtIODevice *vdev, int idx)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+
+ return vhost_virtqueue_pending(&vs->dev, idx);
+}
+
+VirtIODevice *vhost_scsi_init(DeviceState *dev, VirtIOSCSIConf *proxyconf)
+{
+ VHostSCSI *vs;
+ int vhostfd = -1;
+ int ret;
+
+ if (!proxyconf->wwpn) {
+ error_report("vhost-scsi: missing wwpn\n");
+ return NULL;
+ }
+
+ if (proxyconf->vhostfd) {
+ vhostfd = monitor_handle_fd_param(cur_mon, proxyconf->vhostfd);
+ if (vhostfd == -1) {
+ error_report("vhost-scsi: unable to parse vhostfd\n");
+ return NULL;
+ }
+ }
+
+ vs = (VHostSCSI *)virtio_scsi_init_common(dev, proxyconf,
+ sizeof(VHostSCSI));
+
+ vs->vs.vdev.set_config = vhost_scsi_set_config;
+ vs->vs.vdev.set_status = vhost_scsi_set_status;
+ vs->vs.vdev.guest_notifier_mask = vhost_scsi_guest_notifier_mask;
+ vs->vs.vdev.guest_notifier_pending = vhost_scsi_guest_notifier_pending;
+
+ vs->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->vs.conf->num_queues;
+ vs->dev.vqs = g_new(struct vhost_virtqueue, vs->dev.nvqs);
+ vs->dev.vq_index = 0;
+
+ ret = vhost_dev_init(&vs->dev, vhostfd, "/dev/vhost-scsi", true);
+ if (ret < 0) {
+ error_report("vhost-scsi: vhost initialization failed: %s\n",
+ strerror(-ret));
+ return NULL;
+ }
+ vs->dev.backend_features = 0;
+ vs->dev.acked_features = 1ULL << VIRTIO_SCSI_F_HOTPLUG;
+
+ error_setg(&vs->migration_blocker,
+ "vhost-scsi does not support migration");
+ migrate_add_blocker(vs->migration_blocker);
+
+ return &vs->vs.vdev;
+}
+
+void vhost_scsi_exit(VirtIODevice *vdev)
+{
+ VHostSCSI *vs = (VHostSCSI *)vdev;
+ migrate_del_blocker(vs->migration_blocker);
+ error_free(vs->migration_blocker);
+
+ /* This will stop vhost backend. */
+ vhost_scsi_set_status(vdev, 0);
+ g_free(vs->dev.vqs);
+ virtio_cleanup(vdev);
+}
+
diff --git a/hw/vhost-scsi.h b/hw/vhost-scsi.h
new file mode 100644
index 0000000..2e389b4
--- /dev/null
+++ b/hw/vhost-scsi.h
@@ -0,0 +1,65 @@
+/*
+ * vhost_scsi host device
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefanha@xxxxxxxxxxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#ifndef VHOST_SCSI_H
+#define VHOST_SCSI_H
+
+#include "qemu-common.h"
+#include "qdev.h"
+#include "virtio-scsi.h"
+
+/*
+ * Used by QEMU userspace to ensure a consistent vhost-scsi ABI.
+ *
+ * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate +
+ * RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage
+ * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct vhost_scsi_target.
+ * All the targets under vhost_wwpn can be seen and used by guest.
+ */
+
+#define VHOST_SCSI_ABI_VERSION 1
+
+/* TODO #include <linux/vhost.h> properly */
+/* For VHOST_SCSI_SET_ENDPOINT/VHOST_SCSI_CLEAR_ENDPOINT ioctl */
+struct vhost_scsi_target {
+ int abi_version;
+ char vhost_wwpn[224];
+ unsigned short vhost_tpgt;
+ unsigned short reserved;
+};
+
+enum vhost_scsi_vq_list {
+ VHOST_SCSI_VQ_CONTROL = 0,
+ VHOST_SCSI_VQ_EVENT = 1,
+ VHOST_SCSI_VQ_NUM_FIXED = 2,
+};
+
+#define VHOST_VIRTIO 0xAF
+#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
+#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
+#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
+
+#define DEFINE_VHOST_SCSI_PROPERTIES(_state, _features_field, _conf_field) \
+ DEFINE_VIRTIO_COMMON_FEATURES(_state, _features_field), \
+ DEFINE_PROP_STRING("vhostfd", _state, _conf_field.vhostfd), \
+ DEFINE_PROP_STRING("wwpn", _state, _conf_field.wwpn), \
+ DEFINE_PROP_UINT32("num_queues", _state, _conf_field.num_queues, 1), \
+ DEFINE_PROP_UINT32("max_sectors", _state, _conf_field.max_sectors, 0xFFFF), \
+ DEFINE_PROP_UINT32("cmd_per_lun", _state, _conf_field.cmd_per_lun, 128), \
+ DEFINE_PROP_BIT("hotplug", _state, _features_field, VIRTIO_SCSI_F_HOTPLUG, true)
+
+VirtIODevice *vhost_scsi_init(DeviceState *dev, VirtIOSCSIConf *proxyconf);
+void vhost_scsi_exit(VirtIODevice *vdev);
+
+
+#endif
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 39c1966..281a7e2 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -22,6 +22,7 @@
#include "hw/virtio-net.h"
#include "hw/virtio-serial.h"
#include "hw/virtio-scsi.h"
+#include "hw/vhost-scsi.h"
#include "hw/pci/pci.h"
#include "qemu/error-report.h"
#include "hw/pci/msi.h"
@@ -1316,6 +1317,64 @@ static const TypeInfo virtio_scsi_info = {
.class_init = virtio_scsi_class_init,
};
+#ifdef CONFIG_VHOST_SCSI
+static int vhost_scsi_init_pci(PCIDevice *pci_dev)
+{
+ VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
+ VirtIODevice *vdev;
+
+ vdev = vhost_scsi_init(&pci_dev->qdev, &proxy->scsi);
+ if (!vdev) {
+ return -EINVAL;
+ }
+
+ vdev->nvectors = proxy->nvectors == DEV_NVECTORS_UNSPECIFIED
+ ? proxy->scsi.num_queues + 3
+ : proxy->nvectors;
+ virtio_init_pci(proxy, vdev);
+
+ /* make the actual value visible */
+ proxy->nvectors = vdev->nvectors;
+ return 0;
+}
+
+static void vhost_scsi_exit_pci(PCIDevice *pci_dev)
+{
+ VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
+
+ vhost_scsi_exit(proxy->vdev);
+ virtio_exit_pci(pci_dev);
+}
+
+static Property vhost_scsi_properties[] = {
+ DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, DEV_NVECTORS_UNSPECIFIED),
+ DEFINE_VHOST_SCSI_PROPERTIES(VirtIOPCIProxy, host_features, scsi),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_scsi_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+
+ k->init = vhost_scsi_init_pci;
+ k->exit = vhost_scsi_exit_pci;
+ k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+ k->device_id = PCI_DEVICE_ID_VIRTIO_SCSI;
+ k->revision = 0x00;
+ k->class_id = PCI_CLASS_STORAGE_SCSI;
+ dc->reset = virtio_pci_reset;
+ dc->props = vhost_scsi_properties;
+}
+
+static const TypeInfo vhost_scsi_info = {
+ .name = "vhost-scsi-pci",
+ .parent = TYPE_PCI_DEVICE,
+ .instance_size = sizeof(VirtIOPCIProxy),
+ .class_init = vhost_scsi_class_init,
+};
+#endif
+
#ifdef CONFIG_VIRTFS
static int virtio_9p_init_pci(PCIDevice *pci_dev)
{
@@ -1520,6 +1579,9 @@ static void virtio_pci_register_types(void)
type_register_static(&virtio_serial_info);
type_register_static(&virtio_balloon_info);
type_register_static(&virtio_scsi_info);
+#ifdef CONFIG_VHOST_SCSI
+ type_register_static(&vhost_scsi_info);
+#endif
type_register_static(&virtio_rng_info);
type_register_static(&virtio_pci_bus_info);
type_register_static(&virtio_pci_info);
diff --git a/hw/virtio-scsi.h b/hw/virtio-scsi.h
index 5acb721..bbcf206 100644
--- a/hw/virtio-scsi.h
+++ b/hw/virtio-scsi.h
@@ -141,6 +141,8 @@ struct VirtIOSCSIConf {
uint32_t num_queues;
uint32_t max_sectors;
uint32_t cmd_per_lun;
+ char *vhostfd;
+ char *wwpn;
};
typedef struct VirtIOSCSICommon {
--
1.8.1.4
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