[PATCH 28/34] drm/i915/gvt: convert to use vfio_register_emulated_iommu_dev

Christoph Hellwig
2022-04-11T14:17:15Z

This is straightforward conversion, the intel_vgpu already has a pointer
to the vfio_dev, which can be replaced with the embedded structure and
we can replace all the mdev_get_drvdata() with a simple container_of().

Based on an patch from Jason Gunthorpe.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/gpu/drm/i915/gvt/gvt.h | 2 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 190 ++++++++++++++++---------------
2 files changed, 102 insertions(+), 90 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 8565189e0c0dd..c32e8eb199f10 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -211,7 +211,7 @@ struct intel_vgpu {

u32 scan_nonprivbb;

- struct mdev_device *mdev;
+ struct vfio_device vfio_device;
struct vfio_region *region;
int num_regions;
struct eventfd_ctx *intx_trigger;
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 38629ab4c9bf2..4113f850bf92d 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -100,6 +100,9 @@ struct gvt_dma {
struct kref ref;
};

+#define vfio_dev_to_vgpu(vfio_dev) \
+ container_of((vfio_dev), struct intel_vgpu, vfio_device)
+
static void kvmgt_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa,
const u8 *val, int len,
struct kvm_page_track_notifier_node *node);
@@ -723,44 +726,6 @@ int intel_gvt_set_edid(struct intel_vgpu *vgpu, int port_num)
return ret;
}

-static int intel_vgpu_create(struct mdev_device *mdev)
-{
- struct device *pdev = mdev_parent_dev(mdev);
- struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
- struct intel_vgpu_type *type;
- struct intel_vgpu *vgpu;
-
- type = &gvt->types[mdev_get_type_group_id(mdev)];
- if (!type)
- return -EINVAL;
-
- vgpu = intel_gvt_create_vgpu(gvt, type);
- if (IS_ERR(vgpu)) {
- gvt_err("failed to create intel vgpu: %ld\n", PTR_ERR(vgpu));
- return PTR_ERR(vgpu);
- }
-
- INIT_WORK(&vgpu->release_work, intel_vgpu_release_work);
-
- vgpu->mdev = mdev;
- mdev_set_drvdata(mdev, vgpu);
-
- gvt_dbg_core("intel_vgpu_create succeeded for mdev: %s\n",
- dev_name(mdev_dev(mdev)));
- return 0;
-}
-
-static int intel_vgpu_remove(struct mdev_device *mdev)
-{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
-
- if (vgpu->attached)
- return -EBUSY;
-
- intel_gvt_destroy_vgpu(vgpu);
- return 0;
-}
-
static int intel_vgpu_iommu_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
@@ -829,9 +794,9 @@ static bool __kvmgt_vgpu_exist(struct intel_vgpu *vgpu)
return ret;
}

-static int intel_vgpu_open_device(struct mdev_device *mdev)
+static int intel_vgpu_open_device(struct vfio_device *vfio_dev)
{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+ struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
unsigned long events;
int ret;
struct vfio_group *vfio_group;
@@ -840,7 +805,7 @@ static int intel_vgpu_open_device(struct mdev_device *mdev)
vgpu->group_notifier.notifier_call = intel_vgpu_group_notifier;

events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
- ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, &events,
+ ret = vfio_register_notifier(vfio_dev->dev, VFIO_IOMMU_NOTIFY, &events,
&vgpu->iommu_notifier);
if (ret != 0) {
gvt_vgpu_err("vfio_register_notifier for iommu failed: %d\n",
@@ -849,7 +814,7 @@ static int intel_vgpu_open_device(struct mdev_device *mdev)
}

events = VFIO_GROUP_NOTIFY_SET_KVM;
- ret = vfio_register_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, &events,
+ ret = vfio_register_notifier(vfio_dev->dev, VFIO_GROUP_NOTIFY, &events,
&vgpu->group_notifier);
if (ret != 0) {
gvt_vgpu_err("vfio_register_notifier for group failed: %d\n",
@@ -857,7 +822,8 @@ static int intel_vgpu_open_device(struct mdev_device *mdev)
goto undo_iommu;
}

- vfio_group = vfio_group_get_external_user_from_dev(mdev_dev(mdev));
+ vfio_group =
+ vfio_group_get_external_user_from_dev(vgpu->vfio_device.dev);
if (IS_ERR_OR_NULL(vfio_group)) {
ret = !vfio_group ? -EFAULT : PTR_ERR(vfio_group);
gvt_vgpu_err("vfio_group_get_external_user_from_dev failed\n");
@@ -865,14 +831,6 @@ static int intel_vgpu_open_device(struct mdev_device *mdev)
}
vgpu->vfio_group = vfio_group;

- /* Take a module reference as mdev core doesn't take
- * a reference for vendor driver.
- */
- if (!try_module_get(THIS_MODULE)) {
- ret = -ENODEV;
- goto undo_group;
- }
-
ret = -EEXIST;
if (vgpu->attached)
goto undo_group;
@@ -910,11 +868,11 @@ static int intel_vgpu_open_device(struct mdev_device *mdev)
vgpu->vfio_group = NULL;

undo_register:
- vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY,
+ vfio_unregister_notifier(vfio_dev->dev, VFIO_GROUP_NOTIFY,
&vgpu->group_notifier);

undo_iommu:
- vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
+ vfio_unregister_notifier(vfio_dev->dev, VFIO_IOMMU_NOTIFY,
&vgpu->iommu_notifier);
out:
return ret;
@@ -944,19 +902,16 @@ static void __intel_vgpu_release(struct intel_vgpu *vgpu)

intel_gvt_release_vgpu(vgpu);

- ret = vfio_unregister_notifier(mdev_dev(vgpu->mdev), VFIO_IOMMU_NOTIFY,
+ ret = vfio_unregister_notifier(vgpu->vfio_device.dev, VFIO_IOMMU_NOTIFY,
&vgpu->iommu_notifier);
drm_WARN(&i915->drm, ret,
"vfio_unregister_notifier for iommu failed: %d\n", ret);

- ret = vfio_unregister_notifier(mdev_dev(vgpu->mdev), VFIO_GROUP_NOTIFY,
+ ret = vfio_unregister_notifier(vgpu->vfio_device.dev, VFIO_GROUP_NOTIFY,
&vgpu->group_notifier);
drm_WARN(&i915->drm, ret,
"vfio_unregister_notifier for group failed: %d\n", ret);

- /* dereference module reference taken at open */
- module_put(THIS_MODULE);
-
debugfs_remove(debugfs_lookup(KVMGT_DEBUGFS_FILENAME, vgpu->debugfs));

kvm_page_track_unregister_notifier(vgpu->kvm, &vgpu->track_node);
@@ -971,11 +926,9 @@ static void __intel_vgpu_release(struct intel_vgpu *vgpu)
vgpu->attached = false;
}

-static void intel_vgpu_close_device(struct mdev_device *mdev)
+static void intel_vgpu_close_device(struct vfio_device *vfio_dev)
{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
-
- __intel_vgpu_release(vgpu);
+ __intel_vgpu_release(vfio_dev_to_vgpu(vfio_dev));
}

static void intel_vgpu_release_work(struct work_struct *work)
@@ -1127,10 +1080,10 @@ static bool gtt_entry(struct intel_vgpu *vgpu, loff_t *ppos)
true : false;
}

-static ssize_t intel_vgpu_read(struct mdev_device *mdev, char __user *buf,
+static ssize_t intel_vgpu_read(struct vfio_device *vfio_dev, char __user *buf,
size_t count, loff_t *ppos)
{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+ struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
unsigned int done = 0;
int ret;

@@ -1201,11 +1154,11 @@ static ssize_t intel_vgpu_read(struct mdev_device *mdev, char __user *buf,
return -EFAULT;
}

-static ssize_t intel_vgpu_write(struct mdev_device *mdev,
+static ssize_t intel_vgpu_write(struct vfio_device *vfio_dev,
const char __user *buf,
size_t count, loff_t *ppos)
{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+ struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
unsigned int done = 0;
int ret;

@@ -1275,13 +1228,14 @@ static ssize_t intel_vgpu_write(struct mdev_device *mdev,
return -EFAULT;
}

-static int intel_vgpu_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
+static int intel_vgpu_mmap(struct vfio_device *vfio_dev,
+ struct vm_area_struct *vma)
{
+ struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
unsigned int index;
u64 virtaddr;
unsigned long req_size, pgoff, req_start;
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)
@@ -1404,10 +1358,10 @@ static int intel_vgpu_set_irqs(struct intel_vgpu *vgpu, u32 flags,
return func(vgpu, index, start, count, flags, data);
}

-static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd,
+static long intel_vgpu_ioctl(struct vfio_device *vfio_dev, unsigned int cmd,
unsigned long arg)
{
- struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);
+ struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
unsigned long minsz;

gvt_dbg_core("vgpu%d ioctl, cmd: %d\n", vgpu->id, cmd);
@@ -1682,14 +1636,9 @@ static ssize_t
vgpu_id_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- struct mdev_device *mdev = mdev_from_dev(dev);
+ struct intel_vgpu *vgpu = dev_get_drvdata(dev);

- if (mdev) {
- struct intel_vgpu *vgpu = (struct intel_vgpu *)
- mdev_get_drvdata(mdev);
- return sprintf(buf, "%d\n", vgpu->id);
- }
- return sprintf(buf, "\n");
+ return sprintf(buf, "%d\n", vgpu->id);
}

static DEVICE_ATTR_RO(vgpu_id);
@@ -1709,19 +1658,72 @@ static const struct attribute_group *intel_vgpu_groups[] = {
NULL,
};

-const struct mdev_parent_ops intel_vgpu_mdev_ops = {
- .mdev_attr_groups = intel_vgpu_groups,
- .supported_type_groups = gvt_vgpu_type_groups,
- .create = intel_vgpu_create,
- .remove = intel_vgpu_remove,
+static const struct vfio_device_ops intel_vgpu_dev_ops = {
+ .open_device = intel_vgpu_open_device,
+ .close_device = intel_vgpu_close_device,
+ .read = intel_vgpu_read,
+ .write = intel_vgpu_write,
+ .mmap = intel_vgpu_mmap,
+ .ioctl = intel_vgpu_ioctl,
+};

- .open_device = intel_vgpu_open_device,
- .close_device = intel_vgpu_close_device,
+static int intel_vgpu_probe(struct mdev_device *mdev)
+{
+ struct device *pdev = mdev_parent_dev(mdev);
+ struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
+ struct intel_vgpu_type *type;
+ struct intel_vgpu *vgpu;
+ int ret;
+
+ type = &gvt->types[mdev_get_type_group_id(mdev)];
+ if (!type)
+ return -EINVAL;
+
+ vgpu = intel_gvt_create_vgpu(gvt, type);
+ if (IS_ERR(vgpu)) {
+ gvt_err("failed to create intel vgpu: %ld\n", PTR_ERR(vgpu));
+ return PTR_ERR(vgpu);
+ }

- .read = intel_vgpu_read,
- .write = intel_vgpu_write,
- .mmap = intel_vgpu_mmap,
- .ioctl = intel_vgpu_ioctl,
+ INIT_WORK(&vgpu->release_work, intel_vgpu_release_work);
+ vfio_init_group_dev(&vgpu->vfio_device, &mdev->dev,
+ &intel_vgpu_dev_ops);
+
+ dev_set_drvdata(&mdev->dev, vgpu);
+ ret = vfio_register_emulated_iommu_dev(&vgpu->vfio_device);
+ if (ret) {
+ intel_gvt_destroy_vgpu(vgpu);
+ return ret;
+ }
+
+ gvt_dbg_core("intel_vgpu_create succeeded for mdev: %s\n",
+ dev_name(mdev_dev(mdev)));
+ return 0;
+}
+
+static void intel_vgpu_remove(struct mdev_device *mdev)
+{
+ struct intel_vgpu *vgpu = dev_get_drvdata(&mdev->dev);
+
+ if (WARN_ON_ONCE(vgpu->attached))
+ return;
+ intel_gvt_destroy_vgpu(vgpu);
+}
+
+static struct mdev_driver intel_vgpu_mdev_driver = {
+ .driver = {
+ .name = "intel_vgpu_mdev",
+ .owner = THIS_MODULE,
+ .dev_groups = intel_vgpu_groups,
+ },
+ .probe = intel_vgpu_probe,
+ .remove = intel_vgpu_remove,
+};
+
+const struct mdev_parent_ops intel_vgpu_mdev_ops = {
+ .owner = THIS_MODULE,
+ .supported_type_groups = gvt_vgpu_type_groups,
+ .device_driver = &intel_vgpu_mdev_driver,
};

int intel_gvt_page_track_add(struct intel_vgpu *info, u64 gfn)
@@ -1925,11 +1927,21 @@ void intel_gvt_dma_unmap_guest_page(struct intel_vgpu *vgpu,

static int __init kvmgt_init(void)
{
- return intel_gvt_set_ops(&intel_gvt_vgpu_ops);
+ int ret;
+
+ ret = intel_gvt_set_ops(&intel_gvt_vgpu_ops);
+ if (ret)
+ return ret;
+
+ ret = mdev_register_driver(&intel_vgpu_mdev_driver);
+ if (ret)
+ intel_gvt_clear_ops(&intel_gvt_vgpu_ops);
+ return ret;
}

static void __exit kvmgt_exit(void)
{
+ mdev_unregister_driver(&intel_vgpu_mdev_driver);
intel_gvt_clear_ops(&intel_gvt_vgpu_ops);
}

--
2.30.2