1 files changed, 79 insertions, 49 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index 6166e34d892b..e6dfc3331f4b 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -259,7 +259,7 @@ static void write_pte64(struct drm_i915_private *dev_priv,
 	writeq(pte, addr);
 }
 
-static inline struct intel_gvt_gtt_entry *gtt_get_entry64(void *pt,
+static inline int gtt_get_entry64(void *pt,
 		struct intel_gvt_gtt_entry *e,
 		unsigned long index, bool hypervisor_access, unsigned long gpa,
 		struct intel_vgpu *vgpu)
@@ -268,22 +268,23 @@ static inline struct intel_gvt_gtt_entry *gtt_get_entry64(void *pt,
 	int ret;
 
 	if (WARN_ON(info->gtt_entry_size != 8))
-		return e;
+		return -EINVAL;
 
 	if (hypervisor_access) {
 		ret = intel_gvt_hypervisor_read_gpa(vgpu, gpa +
 				(index << info->gtt_entry_size_shift),
 				&e->val64, 8);
-		WARN_ON(ret);
+		if (WARN_ON(ret))
+			return ret;
 	} else if (!pt) {
 		e->val64 = read_pte64(vgpu->gvt->dev_priv, index);
 	} else {
 		e->val64 = *((u64 *)pt + index);
 	}
-	return e;
+	return 0;
 }
 
-static inline struct intel_gvt_gtt_entry *gtt_set_entry64(void *pt,
+static inline int gtt_set_entry64(void *pt,
 		struct intel_gvt_gtt_entry *e,
 		unsigned long index, bool hypervisor_access, unsigned long gpa,
 		struct intel_vgpu *vgpu)
@@ -292,19 +293,20 @@ static inline struct intel_gvt_gtt_entry *gtt_set_entry64(void *pt,
 	int ret;
 
 	if (WARN_ON(info->gtt_entry_size != 8))
-		return e;
+		return -EINVAL;
 
 	if (hypervisor_access) {
 		ret = intel_gvt_hypervisor_write_gpa(vgpu, gpa +
 				(index << info->gtt_entry_size_shift),
 				&e->val64, 8);
-		WARN_ON(ret);
+		if (WARN_ON(ret))
+			return ret;
 	} else if (!pt) {
 		write_pte64(vgpu->gvt->dev_priv, index, e->val64);
 	} else {
 		*((u64 *)pt + index) = e->val64;
 	}
-	return e;
+	return 0;
 }
 
 #define GTT_HAW 46
@@ -445,21 +447,25 @@ static int gtt_entry_p2m(struct intel_vgpu *vgpu, struct intel_gvt_gtt_entry *p,
 /*
  * MM helpers.
  */
-struct intel_gvt_gtt_entry *intel_vgpu_mm_get_entry(struct intel_vgpu_mm *mm,
+int intel_vgpu_mm_get_entry(struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index)
 {
 	struct intel_gvt *gvt = mm->vgpu->gvt;
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
+	int ret;
 
 	e->type = mm->page_table_entry_type;
 
-	ops->get_entry(page_table, e, index, false, 0, mm->vgpu);
+	ret = ops->get_entry(page_table, e, index, false, 0, mm->vgpu);
+	if (ret)
+		return ret;
+
 	ops->test_pse(e);
-	return e;
+	return 0;
 }
 
-struct intel_gvt_gtt_entry *intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
+int intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index)
 {
@@ -472,7 +478,7 @@ struct intel_gvt_gtt_entry *intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
 /*
  * PPGTT shadow page table helpers.
  */
-static inline struct intel_gvt_gtt_entry *ppgtt_spt_get_entry(
+static inline int ppgtt_spt_get_entry(
 		struct intel_vgpu_ppgtt_spt *spt,
 		void *page_table, int type,
 		struct intel_gvt_gtt_entry *e, unsigned long index,
@@ -480,20 +486,24 @@ static inline struct intel_gvt_gtt_entry *ppgtt_spt_get_entry(
 {
 	struct intel_gvt *gvt = spt->vgpu->gvt;
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
+	int ret;
 
 	e->type = get_entry_type(type);
 
 	if (WARN(!gtt_type_is_entry(e->type), "invalid entry type\n"))
-		return e;
+		return -EINVAL;
 
-	ops->get_entry(page_table, e, index, guest,
+	ret = ops->get_entry(page_table, e, index, guest,
 			spt->guest_page.gfn << GTT_PAGE_SHIFT,
 			spt->vgpu);
+	if (ret)
+		return ret;
+
 	ops->test_pse(e);
-	return e;
+	return 0;
 }
 
-static inline struct intel_gvt_gtt_entry *ppgtt_spt_set_entry(
+static inline int ppgtt_spt_set_entry(
 		struct intel_vgpu_ppgtt_spt *spt,
 		void *page_table, int type,
 		struct intel_gvt_gtt_entry *e, unsigned long index,
@@ -503,7 +513,7 @@ static inline struct intel_gvt_gtt_entry *ppgtt_spt_set_entry(
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
 
 	if (WARN(!gtt_type_is_entry(e->type), "invalid entry type\n"))
-		return e;
+		return -EINVAL;
 
 	return ops->set_entry(page_table, e, index, guest,
 			spt->guest_page.gfn << GTT_PAGE_SHIFT,
@@ -792,13 +802,13 @@ static struct intel_vgpu_ppgtt_spt *ppgtt_find_shadow_page(
 
 #define for_each_present_guest_entry(spt, e, i) \
 	for (i = 0; i < pt_entries(spt); i++) \
-	if (spt->vgpu->gvt->gtt.pte_ops->test_present( \
-		ppgtt_get_guest_entry(spt, e, i)))
+		if (!ppgtt_get_guest_entry(spt, e, i) && \
+		    spt->vgpu->gvt->gtt.pte_ops->test_present(e))
 
 #define for_each_present_shadow_entry(spt, e, i) \
 	for (i = 0; i < pt_entries(spt); i++) \
-	if (spt->vgpu->gvt->gtt.pte_ops->test_present( \
-		ppgtt_get_shadow_entry(spt, e, i)))
+		if (!ppgtt_get_shadow_entry(spt, e, i) && \
+		    spt->vgpu->gvt->gtt.pte_ops->test_present(e))
 
 static void ppgtt_get_shadow_page(struct intel_vgpu_ppgtt_spt *spt)
 {
@@ -979,29 +989,26 @@ fail:
 }
 
 static int ppgtt_handle_guest_entry_removal(struct intel_vgpu_guest_page *gpt,
-		unsigned long index)
+		struct intel_gvt_gtt_entry *se, unsigned long index)
 {
 	struct intel_vgpu_ppgtt_spt *spt = guest_page_to_ppgtt_spt(gpt);
 	struct intel_vgpu_shadow_page *sp = &spt->shadow_page;
 	struct intel_vgpu *vgpu = spt->vgpu;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
-	struct intel_gvt_gtt_entry e;
 	int ret;
 
-	ppgtt_get_shadow_entry(spt, &e, index);
-
-	trace_gpt_change(spt->vgpu->id, "remove", spt, sp->type, e.val64,
+	trace_gpt_change(spt->vgpu->id, "remove", spt, sp->type, se->val64,
 			 index);
 
-	if (!ops->test_present(&e))
+	if (!ops->test_present(se))
 		return 0;
 
-	if (ops->get_pfn(&e) == vgpu->gtt.scratch_pt[sp->type].page_mfn)
+	if (ops->get_pfn(se) == vgpu->gtt.scratch_pt[sp->type].page_mfn)
 		return 0;
 
-	if (gtt_type_is_pt(get_next_pt_type(e.type))) {
+	if (gtt_type_is_pt(get_next_pt_type(se->type))) {
 		struct intel_vgpu_ppgtt_spt *s =
-			ppgtt_find_shadow_page(vgpu, ops->get_pfn(&e));
+			ppgtt_find_shadow_page(vgpu, ops->get_pfn(se));
 		if (!s) {
 			gvt_vgpu_err("fail to find guest page\n");
 			ret = -ENXIO;
@@ -1011,12 +1018,10 @@ static int ppgtt_handle_guest_entry_removal(struct intel_vgpu_guest_page *gpt,
 		if (ret)
 			goto fail;
 	}
-	ops->set_pfn(&e, vgpu->gtt.scratch_pt[sp->type].page_mfn);
-	ppgtt_set_shadow_entry(spt, &e, index);
 	return 0;
 fail:
 	gvt_vgpu_err("fail: shadow page %p guest entry 0x%llx type %d\n",
-			spt, e.val64, e.type);
+			spt, se->val64, se->type);
 	return ret;
 }
 
@@ -1236,22 +1241,37 @@ static int ppgtt_handle_guest_write_page_table(
 {
 	struct intel_vgpu_ppgtt_spt *spt = guest_page_to_ppgtt_spt(gpt);
 	struct intel_vgpu *vgpu = spt->vgpu;
+	int type = spt->shadow_page.type;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
+	struct intel_gvt_gtt_entry se;
 
 	int ret;
 	int new_present;
 
 	new_present = ops->test_present(we);
 
-	ret = ppgtt_handle_guest_entry_removal(gpt, index);
-	if (ret)
-		goto fail;
+	/*
+	 * Adding the new entry first and then removing the old one, that can
+	 * guarantee the ppgtt table is validated during the window between
+	 * adding and removal.
+	 */
+	ppgtt_get_shadow_entry(spt, &se, index);
 
 	if (new_present) {
 		ret = ppgtt_handle_guest_entry_add(gpt, we, index);
 		if (ret)
 			goto fail;
 	}
+
+	ret = ppgtt_handle_guest_entry_removal(gpt, &se, index);
+	if (ret)
+		goto fail;
+
+	if (!new_present) {
+		ops->set_pfn(&se, vgpu->gtt.scratch_pt[type].page_mfn);
+		ppgtt_set_shadow_entry(spt, &se, index);
+	}
+
 	return 0;
 fail:
 	gvt_vgpu_err("fail: shadow page %p guest entry 0x%llx type %d.\n",
@@ -1323,7 +1343,7 @@ static int ppgtt_handle_guest_write_page_table_bytes(void *gp,
 	struct intel_vgpu *vgpu = spt->vgpu;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
 	const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
-	struct intel_gvt_gtt_entry we;
+	struct intel_gvt_gtt_entry we, se;
 	unsigned long index;
 	int ret;
 
@@ -1339,7 +1359,8 @@ static int ppgtt_handle_guest_write_page_table_bytes(void *gp,
 			return ret;
 	} else {
 		if (!test_bit(index, spt->post_shadow_bitmap)) {
-			ret = ppgtt_handle_guest_entry_removal(gpt, index);
+			ppgtt_get_shadow_entry(spt, &se, index);
+			ret = ppgtt_handle_guest_entry_removal(gpt, &se, index);
 			if (ret)
 				return ret;
 		}
@@ -1713,8 +1734,10 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 		if (!vgpu_gmadr_is_valid(vgpu, gma))
 			goto err;
 
-		ggtt_get_guest_entry(mm, &e,
-			gma_ops->gma_to_ggtt_pte_index(gma));
+		ret = ggtt_get_guest_entry(mm, &e,
+				gma_ops->gma_to_ggtt_pte_index(gma));
+		if (ret)
+			goto err;
 		gpa = (pte_ops->get_pfn(&e) << GTT_PAGE_SHIFT)
 			+ (gma & ~GTT_PAGE_MASK);
 
@@ -1724,7 +1747,9 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 
 	switch (mm->page_table_level) {
 	case 4:
-		ppgtt_get_shadow_root_entry(mm, &e, 0);
+		ret = ppgtt_get_shadow_root_entry(mm, &e, 0);
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pml4_index(gma);
 		gma_index[1] = gma_ops->gma_to_l4_pdp_index(gma);
 		gma_index[2] = gma_ops->gma_to_pde_index(gma);
@@ -1732,15 +1757,19 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 		index = 4;
 		break;
 	case 3:
-		ppgtt_get_shadow_root_entry(mm, &e,
+		ret = ppgtt_get_shadow_root_entry(mm, &e,
 				gma_ops->gma_to_l3_pdp_index(gma));
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pde_index(gma);
 		gma_index[1] = gma_ops->gma_to_pte_index(gma);
 		index = 2;
 		break;
 	case 2:
-		ppgtt_get_shadow_root_entry(mm, &e,
+		ret = ppgtt_get_shadow_root_entry(mm, &e,
 				gma_ops->gma_to_pde_index(gma));
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pte_index(gma);
 		index = 1;
 		break;
@@ -1755,6 +1784,11 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 			(i == index - 1));
 		if (ret)
 			goto err;
+
+		if (!pte_ops->test_present(&e)) {
+			gvt_dbg_core("GMA 0x%lx is not present\n", gma);
+			goto err;
+		}
 	}
 
 	gpa = (pte_ops->get_pfn(&e) << GTT_PAGE_SHIFT)
@@ -2329,13 +2363,12 @@ void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu)
 /**
  * intel_vgpu_reset_gtt - reset the all GTT related status
  * @vgpu: a vGPU
- * @dmlr: true for vGPU Device Model Level Reset, false for GT Reset
  *
  * This function is called from vfio core to reset reset all
  * GTT related status, including GGTT, PPGTT, scratch page.
  *
  */
-void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr)
+void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu)
 {
 	int i;
 
@@ -2347,9 +2380,6 @@ void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr)
 	 */
 	intel_vgpu_free_mm(vgpu, INTEL_GVT_MM_PPGTT);
 
-	if (!dmlr)
-		return;
-
 	intel_vgpu_reset_ggtt(vgpu);
 
 	/* clear scratch page for security */