drm/i915/gvt/kvmgt: add vfio/mdev support to KVMGT

KVMGT leverages vfio/mdev to mediate device accesses from guest,
this patch adds the vfio/mdev support, thereby completes the
functionality. An intel_vgpu is presented as a mdev device,
and full userspace API compatibility with vfio-pci is kept.
An intel_vgpu_ops is provided to mdev framework, methods get
called to create/remove a vgpu, to open/close it, and to
access it.

Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Xiaoguang Chen <xiaoguang.chen@intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

4 files changed, 907 insertions, 40 deletions

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 5ddde7349fbd..183f5dc1c3f2 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -116,6 +116,7 @@ config DRM_I915_GVT_KVMGT
 	tristate "Enable KVM/VFIO support for Intel GVT-g"
 	depends on DRM_I915_GVT
 	depends on KVM
+	depends on VFIO_MDEV && VFIO_MDEV_DEVICE
 	default n
 	help
 	  Choose this option if you want to enable KVMGT support for
diff --git a/drivers/gpu/drm/i915/gvt/Makefile b/drivers/gpu/drm/i915/gvt/Makefile
index 8a46a7f31d53..b123c20e2097 100644
--- a/drivers/gpu/drm/i915/gvt/Makefile
+++ b/drivers/gpu/drm/i915/gvt/Makefile
@@ -5,6 +5,4 @@ GVT_SOURCE := gvt.o aperture_gm.o handlers.o vgpu.o trace_points.o firmware.o \
 
 ccflags-y				+= -I$(src) -I$(src)/$(GVT_DIR) -Wall
 i915-y					+= $(addprefix $(GVT_DIR)/, $(GVT_SOURCE))
-
-CFLAGS_kvmgt.o				:= -Wno-unused-function
 obj-$(CONFIG_DRM_I915_GVT_KVMGT)	+= $(GVT_DIR)/kvmgt.o
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index b1a7c8dd4b5f..ad0e9364ee70 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -164,15 +164,17 @@ struct intel_vgpu {
 
 #if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT)
 	struct {
-		struct device *mdev;
+		struct mdev_device *mdev;
 		struct vfio_region *region;
 		int num_regions;
 		struct eventfd_ctx *intx_trigger;
 		struct eventfd_ctx *msi_trigger;
 		struct rb_root cache;
 		struct mutex cache_lock;
-		void *vfio_group;
 		struct notifier_block iommu_notifier;
+		struct notifier_block group_notifier;
+		struct kvm *kvm;
+		struct work_struct release_work;
 	} vdev;
 #endif
 };
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 24496ad6a942..4dd6722a7339 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -40,24 +40,13 @@
 #include <linux/uuid.h>
 #include <linux/kvm_host.h>
 #include <linux/vfio.h>
+#include <linux/mdev.h>
 
 #include "i915_drv.h"
 #include "gvt.h"
 
-static inline long kvmgt_pin_pages(struct device *dev, unsigned long *user_pfn,
-			long npage, int prot, unsigned long *phys_pfn)
-{
-	return 0;
-}
-static inline long kvmgt_unpin_pages(struct device *dev, unsigned long *pfn,
-			long npage)
-{
-	return 0;
-}
-
 static const struct intel_gvt_ops *intel_gvt_ops;
 
-
 /* helper macros copied from vfio-pci */
 #define VFIO_PCI_OFFSET_SHIFT   40
 #define VFIO_PCI_OFFSET_TO_INDEX(off)   (off >> VFIO_PCI_OFFSET_SHIFT)
@@ -91,6 +80,15 @@ struct gvt_dma {
 	kvm_pfn_t pfn;
 };
 
+static inline bool handle_valid(unsigned long handle)
+{
+	return !!(handle & ~0xff);
+}
+
+static int kvmgt_guest_init(struct mdev_device *mdev);
+static void intel_vgpu_release_work(struct work_struct *work);
+static bool kvmgt_guest_exit(struct kvmgt_guest_info *info);
+
 static struct gvt_dma *__gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn)
 {
 	struct rb_node *node = vgpu->vdev.cache.rb_node;
@@ -168,9 +166,10 @@ static void __gvt_cache_remove_entry(struct intel_vgpu *vgpu,
 
 static void gvt_cache_remove(struct intel_vgpu *vgpu, gfn_t gfn)
 {
-	struct device *dev = vgpu->vdev.mdev;
+	struct device *dev = &vgpu->vdev.mdev->dev;
 	struct gvt_dma *this;
-	unsigned long pfn;
+	unsigned long g1;
+	int rc;
 
 	mutex_lock(&vgpu->vdev.cache_lock);
 	this  = __gvt_cache_find(vgpu, gfn);
@@ -179,8 +178,9 @@ static void gvt_cache_remove(struct intel_vgpu *vgpu, gfn_t gfn)
 		return;
 	}
 
-	pfn = this->pfn;
-	WARN_ON((kvmgt_unpin_pages(dev, &pfn, 1) != 1));
+	g1 = gfn;
+	rc = vfio_unpin_pages(dev, &g1, 1);
+	WARN_ON(rc != 1);
 	__gvt_cache_remove_entry(vgpu, this);
 	mutex_unlock(&vgpu->vdev.cache_lock);
 }
@@ -195,15 +195,15 @@ static void gvt_cache_destroy(struct intel_vgpu *vgpu)
 {
 	struct gvt_dma *dma;
 	struct rb_node *node = NULL;
-	struct device *dev = vgpu->vdev.mdev;
-	unsigned long pfn;
+	struct device *dev = &vgpu->vdev.mdev->dev;
+	unsigned long gfn;
 
 	mutex_lock(&vgpu->vdev.cache_lock);
 	while ((node = rb_first(&vgpu->vdev.cache))) {
 		dma = rb_entry(node, struct gvt_dma, node);
-		pfn = dma->pfn;
+		gfn = dma->gfn;
 
-		kvmgt_unpin_pages(dev, &pfn, 1);
+		vfio_unpin_pages(dev, &gfn, 1);
 		__gvt_cache_remove_entry(vgpu, dma);
 	}
 	mutex_unlock(&vgpu->vdev.cache_lock);
@@ -227,7 +227,53 @@ static struct intel_vgpu_type *intel_gvt_find_vgpu_type(struct intel_gvt *gvt,
 	return NULL;
 }
 
+static ssize_t available_instance_show(struct kobject *kobj, struct device *dev,
+		char *buf)
+{
+	struct intel_vgpu_type *type;
+	unsigned int num = 0;
+	void *gvt = kdev_to_i915(dev)->gvt;
+
+	type = intel_gvt_find_vgpu_type(gvt, kobject_name(kobj));
+	if (!type)
+		num = 0;
+	else
+		num = type->avail_instance;
+
+	return sprintf(buf, "%u\n", num);
+}
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+		char *buf)
+{
+	return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+
+static ssize_t description_show(struct kobject *kobj, struct device *dev,
+		char *buf)
+{
+	struct intel_vgpu_type *type;
+	void *gvt = kdev_to_i915(dev)->gvt;
+
+	type = intel_gvt_find_vgpu_type(gvt, kobject_name(kobj));
+	if (!type)
+		return 0;
+
+	return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
+				"fence: %d\n",
+				BYTES_TO_MB(type->low_gm_size),
+				BYTES_TO_MB(type->high_gm_size),
+				type->fence);
+}
+
+static MDEV_TYPE_ATTR_RO(available_instance);
+static MDEV_TYPE_ATTR_RO(device_api);
+static MDEV_TYPE_ATTR_RO(description);
+
 static struct attribute *type_attrs[] = {
+	&mdev_type_attr_available_instance.attr,
+	&mdev_type_attr_device_api.attr,
+	&mdev_type_attr_description.attr,
 	NULL,
 };
 
@@ -343,6 +389,720 @@ static void kvmgt_protect_table_del(struct kvmgt_guest_info *info,
 	}
 }
 
+static int intel_vgpu_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+	struct intel_vgpu *vgpu;
+	struct intel_vgpu_type *type;
+	struct device *pdev;
+	void *gvt;
+
+	pdev = mdev->parent->dev;
+	gvt = kdev_to_i915(pdev)->gvt;
+
+	type = intel_gvt_find_vgpu_type(gvt, kobject_name(kobj));
+	if (!type) {
+		gvt_err("failed to find type %s to create\n",
+						kobject_name(kobj));
+		return -EINVAL;
+	}
+
+	vgpu = intel_gvt_ops->vgpu_create(gvt, type);
+	if (IS_ERR_OR_NULL(vgpu)) {
+		gvt_err("create intel vgpu failed\n");
+		return -EINVAL;
+	}
+
+	INIT_WORK(&vgpu->vdev.release_work, intel_vgpu_release_work);
+
+	vgpu->vdev.mdev = mdev;
+	mdev_set_drvdata(mdev, vgpu);
+
+	gvt_dbg_core("intel_vgpu_create succeeded for mdev: %s\n",
+		     dev_name(&mdev->dev));
+	return 0;
+}
+
+static int intel_vgpu_remove(struct mdev_device *mdev)
+{
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+
+	if (handle_valid(vgpu->handle))
+		return -EBUSY;
+
+	intel_gvt_ops->vgpu_destroy(vgpu);
+	return 0;
+}
+
+static int intel_vgpu_iommu_notifier(struct notifier_block *nb,
+				     unsigned long action, void *data)
+{
+	struct intel_vgpu *vgpu = container_of(nb,
+					struct intel_vgpu,
+					vdev.iommu_notifier);
+
+	if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) {
+		struct vfio_iommu_type1_dma_unmap *unmap = data;
+		unsigned long gfn, end_gfn;
+
+		gfn = unmap->iova >> PAGE_SHIFT;
+		end_gfn = gfn + unmap->size / PAGE_SIZE;
+
+		while (gfn < end_gfn)
+			gvt_cache_remove(vgpu, gfn++);
+	}
+
+	return NOTIFY_OK;
+}
+
+static int intel_vgpu_group_notifier(struct notifier_block *nb,
+				     unsigned long action, void *data)
+{
+	struct intel_vgpu *vgpu = container_of(nb,
+					struct intel_vgpu,
+					vdev.group_notifier);
+
+	/* the only action we care about */
+	if (action == VFIO_GROUP_NOTIFY_SET_KVM) {
+		vgpu->vdev.kvm = data;
+
+		if (!data)
+			schedule_work(&vgpu->vdev.release_work);
+	}
+
+	return NOTIFY_OK;
+}
+
+static int intel_vgpu_open(struct mdev_device *mdev)
+{
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+	unsigned long events;
+	int ret;
+
+	vgpu->vdev.iommu_notifier.notifier_call = intel_vgpu_iommu_notifier;
+	vgpu->vdev.group_notifier.notifier_call = intel_vgpu_group_notifier;
+
+	events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
+	ret = vfio_register_notifier(&mdev->dev, VFIO_IOMMU_NOTIFY, &events,
+				&vgpu->vdev.iommu_notifier);
+	if (ret != 0) {
+		gvt_err("vfio_register_notifier for iommu failed: %d\n", ret);
+		goto out;
+	}
+
+	events = VFIO_GROUP_NOTIFY_SET_KVM;
+	ret = vfio_register_notifier(&mdev->dev, VFIO_GROUP_NOTIFY, &events,
+				&vgpu->vdev.group_notifier);
+	if (ret != 0) {
+		gvt_err("vfio_register_notifier for group failed: %d\n", ret);
+		goto undo_iommu;
+	}
+
+	return kvmgt_guest_init(mdev);
+
+undo_iommu:
+	vfio_unregister_notifier(&mdev->dev, VFIO_IOMMU_NOTIFY,
+					&vgpu->vdev.iommu_notifier);
+out:
+	return ret;
+}
+
+static void __intel_vgpu_release(struct intel_vgpu *vgpu)
+{
+	struct kvmgt_guest_info *info;
+
+	if (!handle_valid(vgpu->handle))
+		return;
+
+	vfio_unregister_notifier(&vgpu->vdev.mdev->dev, VFIO_IOMMU_NOTIFY,
+					&vgpu->vdev.iommu_notifier);
+	vfio_unregister_notifier(&vgpu->vdev.mdev->dev, VFIO_GROUP_NOTIFY,
+					&vgpu->vdev.group_notifier);
+
+	info = (struct kvmgt_guest_info *)vgpu->handle;
+	kvmgt_guest_exit(info);
+	vgpu->handle = 0;
+}
+
+static void intel_vgpu_release(struct mdev_device *mdev)
+{
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+
+	__intel_vgpu_release(vgpu);
+}
+
+static void intel_vgpu_release_work(struct work_struct *work)
+{
+	struct intel_vgpu *vgpu = container_of(work, struct intel_vgpu,
+					vdev.release_work);
+	__intel_vgpu_release(vgpu);
+}
+
+static uint64_t intel_vgpu_get_bar0_addr(struct intel_vgpu *vgpu)
+{
+	u32 start_lo, start_hi;
+	u32 mem_type;
+	int pos = PCI_BASE_ADDRESS_0;
+
+	start_lo = (*(u32 *)(vgpu->cfg_space.virtual_cfg_space + pos)) &
+			PCI_BASE_ADDRESS_MEM_MASK;
+	mem_type = (*(u32 *)(vgpu->cfg_space.virtual_cfg_space + pos)) &
+			PCI_BASE_ADDRESS_MEM_TYPE_MASK;
+
+	switch (mem_type) {
+	case PCI_BASE_ADDRESS_MEM_TYPE_64:
+		start_hi = (*(u32 *)(vgpu->cfg_space.virtual_cfg_space
+						+ pos + 4));
+		break;
+	case PCI_BASE_ADDRESS_MEM_TYPE_32:
+	case PCI_BASE_ADDRESS_MEM_TYPE_1M:
+		/* 1M mem BAR treated as 32-bit BAR */
+	default:
+		/* mem unknown type treated as 32-bit BAR */
+		start_hi = 0;
+		break;
+	}
+
+	return ((u64)start_hi << 32) | start_lo;
+}
+
+static ssize_t intel_vgpu_rw(struct mdev_device *mdev, char *buf,
+			size_t count, loff_t *ppos, bool is_write)
+{
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+	unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
+	uint64_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
+	int ret = -EINVAL;
+
+
+	if (index >= VFIO_PCI_NUM_REGIONS) {
+		gvt_err("invalid index: %u\n", index);
+		return -EINVAL;
+	}
+
+	switch (index) {
+	case VFIO_PCI_CONFIG_REGION_INDEX:
+		if (is_write)
+			ret = intel_gvt_ops->emulate_cfg_write(vgpu, pos,
+						buf, count);
+		else
+			ret = intel_gvt_ops->emulate_cfg_read(vgpu, pos,
+						buf, count);
+		break;
+	case VFIO_PCI_BAR0_REGION_INDEX:
+	case VFIO_PCI_BAR1_REGION_INDEX:
+		if (is_write) {
+			uint64_t bar0_start = intel_vgpu_get_bar0_addr(vgpu);
+
+			ret = intel_gvt_ops->emulate_mmio_write(vgpu,
+						bar0_start + pos, buf, count);
+		} else {
+			uint64_t bar0_start = intel_vgpu_get_bar0_addr(vgpu);
+
+			ret = intel_gvt_ops->emulate_mmio_read(vgpu,
+						bar0_start + pos, buf, count);
+		}
+		break;
+	case VFIO_PCI_BAR2_REGION_INDEX:
+	case VFIO_PCI_BAR3_REGION_INDEX:
+	case VFIO_PCI_BAR4_REGION_INDEX:
+	case VFIO_PCI_BAR5_REGION_INDEX:
+	case VFIO_PCI_VGA_REGION_INDEX:
+	case VFIO_PCI_ROM_REGION_INDEX:
+	default:
+		gvt_err("unsupported region: %u\n", index);
+	}
+
+	return ret == 0 ? count : ret;
+}
+
+static ssize_t intel_vgpu_read(struct mdev_device *mdev, char __user *buf,
+			size_t count, loff_t *ppos)
+{
+	unsigned int done = 0;
+	int ret;
+
+	while (count) {
+		size_t filled;
+
+		if (count >= 4 && !(*ppos % 4)) {
+			u32 val;
+
+			ret = intel_vgpu_rw(mdev, (char *)&val, sizeof(val),
+					ppos, false);
+			if (ret <= 0)
+				goto read_err;
+
+			if (copy_to_user(buf, &val, sizeof(val)))
+				goto read_err;
+
+			filled = 4;
+		} else if (count >= 2 && !(*ppos % 2)) {
+			u16 val;
+
+			ret = intel_vgpu_rw(mdev, (char *)&val, sizeof(val),
+					ppos, false);
+			if (ret <= 0)
+				goto read_err;
+
+			if (copy_to_user(buf, &val, sizeof(val)))
+				goto read_err;
+
+			filled = 2;
+		} else {
+			u8 val;
+
+			ret = intel_vgpu_rw(mdev, &val, sizeof(val), ppos,
+					false);
+			if (ret <= 0)
+				goto read_err;
+
+			if (copy_to_user(buf, &val, sizeof(val)))
+				goto read_err;
+
+			filled = 1;
+		}
+
+		count -= filled;
+		done += filled;
+		*ppos += filled;
+		buf += filled;
+	}
+
+	return done;
+
+read_err:
+	return -EFAULT;
+}
+
+static ssize_t intel_vgpu_write(struct mdev_device *mdev,
+				const char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	unsigned int done = 0;
+	int ret;
+
+	while (count) {
+		size_t filled;
+
+		if (count >= 4 && !(*ppos % 4)) {
+			u32 val;
+
+			if (copy_from_user(&val, buf, sizeof(val)))
+				goto write_err;
+
+			ret = intel_vgpu_rw(mdev, (char *)&val, sizeof(val),
+					ppos, true);
+			if (ret <= 0)
+				goto write_err;
+
+			filled = 4;
+		} else if (count >= 2 && !(*ppos % 2)) {
+			u16 val;
+
+			if (copy_from_user(&val, buf, sizeof(val)))
+				goto write_err;
+
+			ret = intel_vgpu_rw(mdev, (char *)&val,
+					sizeof(val), ppos, true);
+			if (ret <= 0)
+				goto write_err;
+
+			filled = 2;
+		} else {
+			u8 val;
+
+			if (copy_from_user(&val, buf, sizeof(val)))
+				goto write_err;
+
+			ret = intel_vgpu_rw(mdev, &val, sizeof(val),
+					ppos, true);
+			if (ret <= 0)
+				goto write_err;
+
+			filled = 1;
+		}
+
+		count -= filled;
+		done += filled;
+		*ppos += filled;
+		buf += filled;
+	}
+
+	return done;
+write_err:
+	return -EFAULT;
+}
+
+static int intel_vgpu_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
+{
+	unsigned int index;
+	u64 virtaddr;
+	unsigned long req_size, pgoff = 0;
+	pgprot_t pg_prot;
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+
+	index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
+	if (index >= VFIO_PCI_ROM_REGION_INDEX)
+		return -EINVAL;
+
+	if (vma->vm_end < vma->vm_start)
+		return -EINVAL;
+	if ((vma->vm_flags & VM_SHARED) == 0)
+		return -EINVAL;
+	if (index != VFIO_PCI_BAR2_REGION_INDEX)
+		return -EINVAL;
+
+	pg_prot = vma->vm_page_prot;
+	virtaddr = vma->vm_start;
+	req_size = vma->vm_end - vma->vm_start;
+	pgoff = vgpu_aperture_pa_base(vgpu) >> PAGE_SHIFT;
+
+	return remap_pfn_range(vma, virtaddr, pgoff, req_size, pg_prot);
+}
+
+static int intel_vgpu_get_irq_count(struct intel_vgpu *vgpu, int type)
+{
+	if (type == VFIO_PCI_INTX_IRQ_INDEX || type == VFIO_PCI_MSI_IRQ_INDEX)
+		return 1;
+
+	return 0;
+}
+
+static int intel_vgpu_set_intx_mask(struct intel_vgpu *vgpu,
+			unsigned int index, unsigned int start,
+			unsigned int count, uint32_t flags,
+			void *data)
+{
+	return 0;
+}
+
+static int intel_vgpu_set_intx_unmask(struct intel_vgpu *vgpu,
+			unsigned int index, unsigned int start,
+			unsigned int count, uint32_t flags, void *data)
+{
+	return 0;
+}
+
+static int intel_vgpu_set_intx_trigger(struct intel_vgpu *vgpu,
+		unsigned int index, unsigned int start, unsigned int count,
+		uint32_t flags, void *data)
+{
+	return 0;
+}
+
+static int intel_vgpu_set_msi_trigger(struct intel_vgpu *vgpu,
+		unsigned int index, unsigned int start, unsigned int count,
+		uint32_t flags, void *data)
+{
+	struct eventfd_ctx *trigger;
+
+	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+		int fd = *(int *)data;
+
+		trigger = eventfd_ctx_fdget(fd);
+		if (IS_ERR(trigger)) {
+			gvt_err("eventfd_ctx_fdget failed\n");
+			return PTR_ERR(trigger);
+		}
+		vgpu->vdev.msi_trigger = trigger;
+	}
+
+	return 0;
+}
+
+static int intel_vgpu_set_irqs(struct intel_vgpu *vgpu, uint32_t flags,
+		unsigned int index, unsigned int start, unsigned int count,
+		void *data)
+{
+	int (*func)(struct intel_vgpu *vgpu, unsigned int index,
+			unsigned int start, unsigned int count, uint32_t flags,
+			void *data) = NULL;
+
+	switch (index) {
+	case VFIO_PCI_INTX_IRQ_INDEX:
+		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+		case VFIO_IRQ_SET_ACTION_MASK:
+			func = intel_vgpu_set_intx_mask;
+			break;
+		case VFIO_IRQ_SET_ACTION_UNMASK:
+			func = intel_vgpu_set_intx_unmask;
+			break;
+		case VFIO_IRQ_SET_ACTION_TRIGGER:
+			func = intel_vgpu_set_intx_trigger;
+			break;
+		}
+		break;
+	case VFIO_PCI_MSI_IRQ_INDEX:
+		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+		case VFIO_IRQ_SET_ACTION_MASK:
+		case VFIO_IRQ_SET_ACTION_UNMASK:
+			/* XXX Need masking support exported */
+			break;
+		case VFIO_IRQ_SET_ACTION_TRIGGER:
+			func = intel_vgpu_set_msi_trigger;
+			break;
+		}
+		break;
+	}
+
+	if (!func)
+		return -ENOTTY;
+
+	return func(vgpu, index, start, count, flags, data);
+}
+
+static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd,
+			     unsigned long arg)
+{
+	struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+	unsigned long minsz;
+
+	gvt_dbg_core("vgpu%d ioctl, cmd: %d\n", vgpu->id, cmd);
+
+	if (cmd == VFIO_DEVICE_GET_INFO) {
+		struct vfio_device_info info;
+
+		minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz)
+			return -EINVAL;
+
+		info.flags = VFIO_DEVICE_FLAGS_PCI;
+		info.flags |= VFIO_DEVICE_FLAGS_RESET;
+		info.num_regions = VFIO_PCI_NUM_REGIONS;
+		info.num_irqs = VFIO_PCI_NUM_IRQS;
+
+		return copy_to_user((void __user *)arg, &info, minsz) ?
+			-EFAULT : 0;
+
+	} else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
+		struct vfio_region_info info;
+		struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
+		int i, ret;
+		struct vfio_region_info_cap_sparse_mmap *sparse = NULL;
+		size_t size;
+		int nr_areas = 1;
+		int cap_type_id;
+
+		minsz = offsetofend(struct vfio_region_info, offset);
+
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz)
+			return -EINVAL;
+
+		switch (info.index) {
+		case VFIO_PCI_CONFIG_REGION_INDEX:
+			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+			info.size = INTEL_GVT_MAX_CFG_SPACE_SZ;
+			info.flags = VFIO_REGION_INFO_FLAG_READ |
+				     VFIO_REGION_INFO_FLAG_WRITE;
+			break;
+		case VFIO_PCI_BAR0_REGION_INDEX:
+			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+			info.size = vgpu->cfg_space.bar[info.index].size;
+			if (!info.size) {
+				info.flags = 0;
+				break;
+			}
+
+			info.flags = VFIO_REGION_INFO_FLAG_READ |
+				     VFIO_REGION_INFO_FLAG_WRITE;
+			break;
+		case VFIO_PCI_BAR1_REGION_INDEX:
+			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+			info.size = 0;
+			info.flags = 0;
+			break;
+		case VFIO_PCI_BAR2_REGION_INDEX:
+			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+			info.flags = VFIO_REGION_INFO_FLAG_CAPS |
+					VFIO_REGION_INFO_FLAG_MMAP |
+					VFIO_REGION_INFO_FLAG_READ |
+					VFIO_REGION_INFO_FLAG_WRITE;
+			info.size = gvt_aperture_sz(vgpu->gvt);
+
+			size = sizeof(*sparse) +
+					(nr_areas * sizeof(*sparse->areas));
+			sparse = kzalloc(size, GFP_KERNEL);
+			if (!sparse)
+				return -ENOMEM;
+
+			sparse->nr_areas = nr_areas;
+			cap_type_id = VFIO_REGION_INFO_CAP_SPARSE_MMAP;
+			sparse->areas[0].offset =
+					PAGE_ALIGN(vgpu_aperture_offset(vgpu));
+			sparse->areas[0].size = vgpu_aperture_sz(vgpu);
+			if (!caps.buf) {
+				kfree(caps.buf);
+				caps.buf = NULL;
+				caps.size = 0;
+			}
+			break;
+
+		case VFIO_PCI_BAR3_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
+			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+			info.size = 0;
+
+			info.flags = 0;
+			gvt_dbg_core("get region info bar:%d\n", info.index);
+			break;
+
+		case VFIO_PCI_ROM_REGION_INDEX:
+		case VFIO_PCI_VGA_REGION_INDEX:
+			gvt_dbg_core("get region info index:%d\n", info.index);
+			break;
+		default:
+			{
+				struct vfio_region_info_cap_type cap_type;
+
+				if (info.index >= VFIO_PCI_NUM_REGIONS +
+						vgpu->vdev.num_regions)
+					return -EINVAL;
+
+				i = info.index - VFIO_PCI_NUM_REGIONS;
+
+				info.offset =
+					VFIO_PCI_INDEX_TO_OFFSET(info.index);
+				info.size = vgpu->vdev.region[i].size;
+				info.flags = vgpu->vdev.region[i].flags;
+
+				cap_type.type = vgpu->vdev.region[i].type;
+				cap_type.subtype = vgpu->vdev.region[i].subtype;
+
+				ret = vfio_info_add_capability(&caps,
+						VFIO_REGION_INFO_CAP_TYPE,
+						&cap_type);
+				if (ret)
+					return ret;
+			}
+		}
+
+		if ((info.flags & VFIO_REGION_INFO_FLAG_CAPS) && sparse) {
+			switch (cap_type_id) {
+			case VFIO_REGION_INFO_CAP_SPARSE_MMAP:
+				ret = vfio_info_add_capability(&caps,
+					VFIO_REGION_INFO_CAP_SPARSE_MMAP,
+					sparse);
+				kfree(sparse);
+				if (ret)
+					return ret;
+				break;
+			default:
+				return -EINVAL;
+			}
+		}
+
+		if (caps.size) {
+			if (info.argsz < sizeof(info) + caps.size) {
+				info.argsz = sizeof(info) + caps.size;
+				info.cap_offset = 0;
+			} else {
+				vfio_info_cap_shift(&caps, sizeof(info));
+				if (copy_to_user((void __user *)arg +
+						  sizeof(info), caps.buf,
+						  caps.size)) {
+					kfree(caps.buf);
+					return -EFAULT;
+				}
+				info.cap_offset = sizeof(info);
+			}
+
+			kfree(caps.buf);
+		}
+
+		return copy_to_user((void __user *)arg, &info, minsz) ?
+			-EFAULT : 0;
+	} else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
+		struct vfio_irq_info info;
+
+		minsz = offsetofend(struct vfio_irq_info, count);
+
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS)
+			return -EINVAL;
+
+		switch (info.index) {
+		case VFIO_PCI_INTX_IRQ_INDEX:
+		case VFIO_PCI_MSI_IRQ_INDEX:
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		info.flags = VFIO_IRQ_INFO_EVENTFD;
+
+		info.count = intel_vgpu_get_irq_count(vgpu, info.index);
+
+		if (info.index == VFIO_PCI_INTX_IRQ_INDEX)
+			info.flags |= (VFIO_IRQ_INFO_MASKABLE |
+				       VFIO_IRQ_INFO_AUTOMASKED);
+		else
+			info.flags |= VFIO_IRQ_INFO_NORESIZE;
+
+		return copy_to_user((void __user *)arg, &info, minsz) ?
+			-EFAULT : 0;
+	} else if (cmd == VFIO_DEVICE_SET_IRQS) {
+		struct vfio_irq_set hdr;
+		u8 *data = NULL;
+		int ret = 0;
+		size_t data_size = 0;
+
+		minsz = offsetofend(struct vfio_irq_set, count);
+
+		if (copy_from_user(&hdr, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
+			int max = intel_vgpu_get_irq_count(vgpu, hdr.index);
+
+			ret = vfio_set_irqs_validate_and_prepare(&hdr, max,
+						VFIO_PCI_NUM_IRQS, &data_size);
+			if (ret) {
+				gvt_err("intel:vfio_set_irqs_validate_and_prepare failed\n");
+				return -EINVAL;
+			}
+			if (data_size) {
+				data = memdup_user((void __user *)(arg + minsz),
+						   data_size);
+				if (IS_ERR(data))
+					return PTR_ERR(data);
+			}
+		}
+
+		ret = intel_vgpu_set_irqs(vgpu, hdr.flags, hdr.index,
+					hdr.start, hdr.count, data);
+		kfree(data);
+
+		return ret;
+	} else if (cmd == VFIO_DEVICE_RESET) {
+		intel_gvt_ops->vgpu_reset(vgpu);
+		return 0;
+	}
+
+	return 0;
+}
+
+static const struct parent_ops intel_vgpu_ops = {
+	.supported_type_groups	= intel_vgpu_type_groups,
+	.create			= intel_vgpu_create,
+	.remove			= intel_vgpu_remove,
+
+	.open			= intel_vgpu_open,
+	.release		= intel_vgpu_release,
+
+	.read			= intel_vgpu_read,
+	.write			= intel_vgpu_write,
+	.mmap			= intel_vgpu_mmap,
+	.ioctl			= intel_vgpu_ioctl,
+};
+
 static int kvmgt_host_init(struct device *dev, void *gvt, const void *ops)
 {
 	if (!intel_gvt_init_vgpu_type_groups(gvt))
@@ -350,22 +1110,28 @@ static int kvmgt_host_init(struct device *dev, void *gvt, const void *ops)
 
 	intel_gvt_ops = ops;
 
-	/* MDEV is not yet available */
-	return -ENODEV;
+	return mdev_register_device(dev, &intel_vgpu_ops);
 }
 
 static void kvmgt_host_exit(struct device *dev, void *gvt)
 {
 	intel_gvt_cleanup_vgpu_type_groups(gvt);
+	mdev_unregister_device(dev);
 }
 
 static int kvmgt_write_protect_add(unsigned long handle, u64 gfn)
 {
-	struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle;
-	struct kvm *kvm = info->kvm;
+	struct kvmgt_guest_info *info;
+	struct kvm *kvm;
 	struct kvm_memory_slot *slot;
 	int idx;
 
+	if (!handle_valid(handle))
+		return -ESRCH;
+
+	info = (struct kvmgt_guest_info *)handle;
+	kvm = info->kvm;
+
 	idx = srcu_read_lock(&kvm->srcu);
 	slot = gfn_to_memslot(kvm, gfn);
 
@@ -385,11 +1151,17 @@ out:
 
 static int kvmgt_write_protect_remove(unsigned long handle, u64 gfn)
 {
-	struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle;
-	struct kvm *kvm = info->kvm;
+	struct kvmgt_guest_info *info;
+	struct kvm *kvm;
 	struct kvm_memory_slot *slot;
 	int idx;
 
+	if (!handle_valid(handle))
+		return 0;
+
+	info = (struct kvmgt_guest_info *)handle;
+	kvm = info->kvm;
+
 	idx = srcu_read_lock(&kvm->srcu);
 	slot = gfn_to_memslot(kvm, gfn);
 
@@ -477,6 +1249,85 @@ static int kvmgt_detect_host(void)
 	return kvmgt_check_guest() ? -ENODEV : 0;
 }
 
+static bool __kvmgt_vgpu_exist(struct intel_vgpu *vgpu, struct kvm *kvm)
+{
+	struct intel_vgpu *itr;
+	struct kvmgt_guest_info *info;
+	int id;
+	bool ret = false;
+
+	mutex_lock(&vgpu->gvt->lock);
+	for_each_active_vgpu(vgpu->gvt, itr, id) {
+		if (!handle_valid(itr->handle))
+			continue;
+
+		info = (struct kvmgt_guest_info *)itr->handle;
+		if (kvm && kvm == info->kvm) {
+			ret = true;
+			goto out;
+		}
+	}
+out:
+	mutex_unlock(&vgpu->gvt->lock);
+	return ret;
+}
+
+static int kvmgt_guest_init(struct mdev_device *mdev)
+{
+	struct kvmgt_guest_info *info;
+	struct intel_vgpu *vgpu;
+	struct kvm *kvm;
+
+	vgpu = mdev_get_drvdata(mdev);
+	if (handle_valid(vgpu->handle))
+		return -EEXIST;
+
+	kvm = vgpu->vdev.kvm;
+	if (!kvm || kvm->mm != current->mm) {
+		gvt_err("KVM is required to use Intel vGPU\n");
+		return -ESRCH;
+	}
+
+	if (__kvmgt_vgpu_exist(vgpu, kvm))
+		return -EEXIST;
+
+	info = vzalloc(sizeof(struct kvmgt_guest_info));
+	if (!info)
+		return -ENOMEM;
+
+	vgpu->handle = (unsigned long)info;
+	info->vgpu = vgpu;
+	info->kvm = kvm;
+
+	kvmgt_protect_table_init(info);
+	gvt_cache_init(vgpu);
+
+	info->track_node.track_write = kvmgt_page_track_write;
+	info->track_node.track_flush_slot = kvmgt_page_track_flush_slot;
+	kvm_page_track_register_notifier(kvm, &info->track_node);
+
+	return 0;
+}
+
+static bool kvmgt_guest_exit(struct kvmgt_guest_info *info)
+{
+	struct intel_vgpu *vgpu;
+
+	if (!info) {
+		gvt_err("kvmgt_guest_info invalid\n");
+		return false;
+	}
+
+	vgpu = info->vgpu;
+
+	kvm_page_track_unregister_notifier(info->kvm, &info->track_node);
+	kvmgt_protect_table_destroy(info);
+	gvt_cache_destroy(vgpu);
+	vfree(info);
+
+	return true;
+}
+
 static int kvmgt_attach_vgpu(void *vgpu, unsigned long *handle)
 {
 	/* nothing to do here */
@@ -490,30 +1341,42 @@ static void kvmgt_detach_vgpu(unsigned long handle)
 
 static int kvmgt_inject_msi(unsigned long handle, u32 addr, u16 data)
 {
-	struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle;
-	struct intel_vgpu *vgpu = info->vgpu;
+	struct kvmgt_guest_info *info;
+	struct intel_vgpu *vgpu;
 
-	if (vgpu->vdev.msi_trigger)
-		return eventfd_signal(vgpu->vdev.msi_trigger, 1) == 1;
+	if (!handle_valid(handle))
+		return -ESRCH;
 
-	return false;
+	info = (struct kvmgt_guest_info *)handle;
+	vgpu = info->vgpu;
+
+	if (eventfd_signal(vgpu->vdev.msi_trigger, 1) == 1)
+		return 0;
+
+	return -EFAULT;
 }
 
 static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn)
 {
 	unsigned long pfn;
-	struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle;
+	struct kvmgt_guest_info *info;
+	struct device *dev;
 	int rc;
 
+	if (!handle_valid(handle))
+		return INTEL_GVT_INVALID_ADDR;
+
+	info = (struct kvmgt_guest_info *)handle;
 	pfn = gvt_cache_find(info->vgpu, gfn);
 	if (pfn != 0)
 		return pfn;
 
-	rc = kvmgt_pin_pages(info->vgpu->vdev.mdev, &gfn, 1,
-			     IOMMU_READ | IOMMU_WRITE, &pfn);
+	pfn = INTEL_GVT_INVALID_ADDR;
+	dev = &info->vgpu->vdev.mdev->dev;
+	rc = vfio_pin_pages(dev, &gfn, 1, IOMMU_READ | IOMMU_WRITE, &pfn);
 	if (rc != 1) {
-		gvt_err("vfio_pin_pages failed for gfn: 0x%lx\n", gfn);
-		return 0;
+		gvt_err("vfio_pin_pages failed for gfn 0x%lx: %d\n", gfn, rc);
+		return INTEL_GVT_INVALID_ADDR;
 	}
 
 	gvt_cache_add(info->vgpu, gfn, pfn);
@@ -528,6 +1391,9 @@ static int kvmgt_rw_gpa(unsigned long handle, unsigned long gpa,
 	int ret;
 	bool kthread = current->mm == NULL;
 
+	if (!handle_valid(handle))
+		return -ESRCH;
+
 	info = (struct kvmgt_guest_info *)handle;
 	kvm = info->kvm;