[PATCH v6 2/6] drm/i915/gvt: OpRegion support for GVT-g

From: Xiaoguang Chen
Date: Sat May 27 2017 - 04:41:10 EST


OpRegion is needed to support display related operation for
intel vgpu.

A vfio device region is added to intel vgpu to deliver the
host OpRegion information to user space so user space can
construct the OpRegion for vgpu.

Signed-off-by: Bing Niu <bing.niu@xxxxxxxxx>
Signed-off-by: Xiaoguang Chen <xiaoguang.chen@xxxxxxxxx>
---
drivers/gpu/drm/i915/gvt/kvmgt.c | 97 +++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/gvt/opregion.c | 8 ++-
2 files changed, 104 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 3c6a02b..389f072 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -53,6 +53,8 @@ static const struct intel_gvt_ops *intel_gvt_ops;
#define VFIO_PCI_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_PCI_OFFSET_SHIFT)
#define VFIO_PCI_OFFSET_MASK (((u64)(1) << VFIO_PCI_OFFSET_SHIFT) - 1)

+#define OPREGION_SIGNATURE "IntelGraphicsMem"
+
struct vfio_region;
struct intel_vgpu_regops {
size_t (*rw)(struct intel_vgpu *vgpu, char *buf,
@@ -436,6 +438,92 @@ static void kvmgt_protect_table_del(struct kvmgt_guest_info *info,
}
}

+static size_t intel_vgpu_reg_rw_opregion(struct intel_vgpu *vgpu, char *buf,
+ size_t count, loff_t *ppos, bool iswrite)
+{
+ unsigned int i = VFIO_PCI_OFFSET_TO_INDEX(*ppos) -
+ VFIO_PCI_NUM_REGIONS;
+ void *base = vgpu->vdev.region[i].data;
+ loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
+
+ if (pos >= vgpu->vdev.region[i].size || iswrite) {
+ gvt_vgpu_err("invalid op or offset for Intel vgpu OpRegion\n");
+ return -EINVAL;
+ }
+ count = min(count, (size_t)(vgpu->vdev.region[i].size - pos));
+ memcpy(buf, base + pos, count);
+
+ return count;
+}
+
+static void intel_vgpu_reg_release_opregion(struct intel_vgpu *vgpu,
+ struct vfio_region *region)
+{
+ memunmap(region->data);
+}
+
+static const struct intel_vgpu_regops intel_vgpu_regops_opregion = {
+ .rw = intel_vgpu_reg_rw_opregion,
+ .release = intel_vgpu_reg_release_opregion,
+};
+
+static int intel_vgpu_register_reg(struct intel_vgpu *vgpu,
+ unsigned int type, unsigned int subtype,
+ const struct intel_vgpu_regops *ops,
+ size_t size, u32 flags, void *data)
+{
+ struct vfio_region *region;
+
+ region = krealloc(vgpu->vdev.region,
+ (vgpu->vdev.num_regions + 1) * sizeof(*region),
+ GFP_KERNEL);
+ if (!region)
+ return -ENOMEM;
+
+ vgpu->vdev.region = region;
+ vgpu->vdev.region[vgpu->vdev.num_regions].type = type;
+ vgpu->vdev.region[vgpu->vdev.num_regions].subtype = subtype;
+ vgpu->vdev.region[vgpu->vdev.num_regions].ops = ops;
+ vgpu->vdev.region[vgpu->vdev.num_regions].size = size;
+ vgpu->vdev.region[vgpu->vdev.num_regions].flags = flags;
+ vgpu->vdev.region[vgpu->vdev.num_regions].data = data;
+ vgpu->vdev.num_regions++;
+
+ return 0;
+}
+
+static int intel_vgpu_reg_init_opregion(struct intel_vgpu *vgpu)
+{
+ unsigned int addr;
+ void *base;
+ int ret;
+
+ addr = vgpu->gvt->opregion.opregion_pa;
+ if (!addr || !(~addr))
+ return -ENODEV;
+
+ base = memremap(addr, OPREGION_SIZE, MEMREMAP_WB);
+ if (!base)
+ return -ENOMEM;
+
+ if (memcmp(base, OPREGION_SIGNATURE, 16)) {
+ memunmap(base);
+ return -EINVAL;
+ }
+
+ ret = intel_vgpu_register_reg(vgpu,
+ PCI_VENDOR_ID_INTEL | VFIO_REGION_TYPE_PCI_VENDOR_TYPE,
+ VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION,
+ &intel_vgpu_regops_opregion, OPREGION_SIZE,
+ VFIO_REGION_INFO_FLAG_READ, base);
+ if (ret) {
+ memunmap(base);
+ return ret;
+ }
+
+ return ret;
+}
+
static int intel_vgpu_create(struct kobject *kobj, struct mdev_device *mdev)
{
struct intel_vgpu *vgpu = NULL;
@@ -467,6 +555,15 @@ static int intel_vgpu_create(struct kobject *kobj, struct mdev_device *mdev)
vgpu->vdev.mdev = mdev;
mdev_set_drvdata(mdev, vgpu);

+ ret = intel_vgpu_reg_init_opregion(vgpu);
+ if (ret) {
+ gvt_vgpu_err("create OpRegion failed\n");
+ goto out;
+ }
+
+ gvt_dbg_core("create OpRegion succeeded for mdev:%s\n",
+ dev_name(mdev_dev(mdev)));
+
gvt_dbg_core("intel_vgpu_create succeeded for mdev: %s\n",
dev_name(mdev_dev(mdev)));
ret = 0;
diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
index 3117991..5c7496d 100644
--- a/drivers/gpu/drm/i915/gvt/opregion.c
+++ b/drivers/gpu/drm/i915/gvt/opregion.c
@@ -114,6 +114,7 @@ void intel_vgpu_clean_opregion(struct intel_vgpu *vgpu)
int intel_vgpu_init_opregion(struct intel_vgpu *vgpu, u32 gpa)
{
int ret;
+ unsigned long pfn;

gvt_dbg_core("vgpu%d: init vgpu opregion\n", vgpu->id);

@@ -127,7 +128,12 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu, u32 gpa)
ret = map_vgpu_opregion(vgpu, true);
if (ret)
return ret;
- }
+ } else {
+ pfn = intel_gvt_hypervisor_gfn_to_mfn(vgpu, gpa >> PAGE_SHIFT);
+ vgpu_opregion(vgpu)->va = memremap(pfn << PAGE_SHIFT,
+ INTEL_GVT_OPREGION_SIZE,
+ MEMREMAP_WB);
+ }

return 0;
}
--
2.7.4