From b86dc6ed20f1543121757da1a77c0f52121d8bf1 Mon Sep 17 00:00:00 2001 From: Chuanxiao Dong Date: Thu, 9 Feb 2017 11:38:01 +0800 Subject: [PATCH] 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 Signed-off-by: Zhenyu Wang --- drivers/gpu/drm/i915/gvt/kvmgt.c | 62 +++++++++++++++++++++++++++++++--------- 1 file changed, 49 insertions(+), 13 deletions(-) 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 kvmgt_guest_info { 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 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 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 @@ out: 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 @@ static void gvt_cache_add(struct intel_vgpu *vgpu, gfn_t gfn, kvm_pfn_t pfn) return; new->gfn = gfn; - new->pfn = pfn; + new->iova = iova; mutex_lock(&vgpu->vdev.cache_lock); while (*link) { @@ -182,6 +212,7 @@ static void gvt_cache_remove(struct intel_vgpu *vgpu, gfn_t gfn) } 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 @@ static void gvt_cache_destroy(struct intel_vgpu *vgpu) 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 int kvmgt_inject_msi(unsigned long handle, u32 addr, u16 data) 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 @@ static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn) 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 @@ static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn) 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, -- 2.7.4