drm/i915/gvt: map pfn for PTE entry in kvm
When host i915 iommu enabled, gvt needs to use a mapped pfn in PTE entry
So before kvm returns the pfn, map this pfn and return the mapped address
which is so called iova.
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index b49a01d..c429ed0 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -77,7 +77,7 @@
struct gvt_dma {
struct rb_node node;
gfn_t gfn;
- kvm_pfn_t pfn;
+ unsigned long iova;
};
static inline bool handle_valid(unsigned long handle)
@@ -89,6 +89,35 @@
static void intel_vgpu_release_work(struct work_struct *work);
static bool kvmgt_guest_exit(struct kvmgt_guest_info *info);
+static int gvt_dma_map_iova(struct intel_vgpu *vgpu, kvm_pfn_t pfn,
+ unsigned long *iova)
+{
+ struct page *page;
+ struct device *dev = &vgpu->gvt->dev_priv->drm.pdev->dev;
+ dma_addr_t daddr;
+
+ page = pfn_to_page(pfn);
+ if (is_error_page(page))
+ return -EFAULT;
+
+ daddr = dma_map_page(dev, page, 0, PAGE_SIZE,
+ PCI_DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(dev, daddr))
+ return -ENOMEM;
+
+ *iova = (unsigned long)(daddr >> PAGE_SHIFT);
+ return 0;
+}
+
+static void gvt_dma_unmap_iova(struct intel_vgpu *vgpu, unsigned long iova)
+{
+ struct device *dev = &vgpu->gvt->dev_priv->drm.pdev->dev;
+ dma_addr_t daddr;
+
+ daddr = (dma_addr_t)(iova << PAGE_SHIFT);
+ dma_unmap_page(dev, daddr, PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
+}
+
static struct gvt_dma *__gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn)
{
struct rb_node *node = vgpu->vdev.cache.rb_node;
@@ -111,21 +140,22 @@
return ret;
}
-static kvm_pfn_t gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn)
+static unsigned long gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn)
{
struct gvt_dma *entry;
- kvm_pfn_t pfn;
+ unsigned long iova;
mutex_lock(&vgpu->vdev.cache_lock);
entry = __gvt_cache_find(vgpu, gfn);
- pfn = (entry == NULL) ? 0 : entry->pfn;
+ iova = (entry == NULL) ? INTEL_GVT_INVALID_ADDR : entry->iova;
mutex_unlock(&vgpu->vdev.cache_lock);
- return pfn;
+ return iova;
}
-static void gvt_cache_add(struct intel_vgpu *vgpu, gfn_t gfn, kvm_pfn_t pfn)
+static void gvt_cache_add(struct intel_vgpu *vgpu, gfn_t gfn,
+ unsigned long iova)
{
struct gvt_dma *new, *itr;
struct rb_node **link = &vgpu->vdev.cache.rb_node, *parent = NULL;
@@ -135,7 +165,7 @@
return;
new->gfn = gfn;
- new->pfn = pfn;
+ new->iova = iova;
mutex_lock(&vgpu->vdev.cache_lock);
while (*link) {
@@ -182,6 +212,7 @@
}
g1 = gfn;
+ gvt_dma_unmap_iova(vgpu, this->iova);
rc = vfio_unpin_pages(dev, &g1, 1);
WARN_ON(rc != 1);
__gvt_cache_remove_entry(vgpu, this);
@@ -204,6 +235,7 @@
mutex_lock(&vgpu->vdev.cache_lock);
while ((node = rb_first(&vgpu->vdev.cache))) {
dma = rb_entry(node, struct gvt_dma, node);
+ gvt_dma_unmap_iova(vgpu, dma->iova);
gfn = dma->gfn;
vfio_unpin_pages(dev, &gfn, 1);
@@ -1348,7 +1380,7 @@
static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn)
{
- unsigned long pfn;
+ unsigned long iova, pfn;
struct kvmgt_guest_info *info;
struct device *dev;
int rc;
@@ -1357,9 +1389,9 @@
return INTEL_GVT_INVALID_ADDR;
info = (struct kvmgt_guest_info *)handle;
- pfn = gvt_cache_find(info->vgpu, gfn);
- if (pfn != 0)
- return pfn;
+ iova = gvt_cache_find(info->vgpu, gfn);
+ if (iova != INTEL_GVT_INVALID_ADDR)
+ return iova;
pfn = INTEL_GVT_INVALID_ADDR;
dev = mdev_dev(info->vgpu->vdev.mdev);
@@ -1368,9 +1400,13 @@
gvt_err("vfio_pin_pages failed for gfn 0x%lx: %d\n", gfn, rc);
return INTEL_GVT_INVALID_ADDR;
}
+ /* transfer to host iova for GFX to use DMA */
+ rc = gvt_dma_map_iova(info->vgpu, pfn, &iova);
+ if (rc)
+ gvt_err("gvt_dma_map_iova failed for gfn: 0x%lx\n", gfn);
- gvt_cache_add(info->vgpu, gfn, pfn);
- return pfn;
+ gvt_cache_add(info->vgpu, gfn, iova);
+ return iova;
}
static int kvmgt_rw_gpa(unsigned long handle, unsigned long gpa,