diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 489f8db..d3ad517 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -560,6 +560,7 @@ static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
 {
 	struct i915_hw_ppgtt *ppgtt =
 		container_of(vm, struct i915_hw_ppgtt, base);
+	struct i915_page_directory_pointer_entry *pdp = &ppgtt->pdp; /* FIXME: 48b */
 	gen8_gtt_pte_t *pt_vaddr, scratch_pte;
 	unsigned pdpe = start >> GEN8_PDPE_SHIFT & GEN8_PDPE_MASK;
 	unsigned pde = start >> GEN8_PDE_SHIFT & GEN8_PDE_MASK;
@@ -575,10 +576,10 @@ static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
 		struct i915_page_table_entry *pt;
 		struct page *page_table;
 
-		if (WARN_ON(!ppgtt->pdp.page_directory[pdpe]))
+		if (WARN_ON(!pdp->page_directory[pdpe]))
 			continue;
 
-		pd = ppgtt->pdp.page_directory[pdpe];
+		pd = pdp->page_directory[pdpe];
 
 		if (WARN_ON(!pd->page_tables[pde]))
 			continue;
@@ -620,6 +621,7 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
 {
 	struct i915_hw_ppgtt *ppgtt =
 		container_of(vm, struct i915_hw_ppgtt, base);
+	struct i915_page_directory_pointer_entry *pdp = &ppgtt->pdp; /* FIXME: 48b */
 	gen8_gtt_pte_t *pt_vaddr;
 	unsigned pdpe = start >> GEN8_PDPE_SHIFT & GEN8_PDPE_MASK;
 	unsigned pde = start >> GEN8_PDE_SHIFT & GEN8_PDE_MASK;
@@ -630,7 +632,7 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
 
 	for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
 		if (pt_vaddr == NULL) {
-			struct i915_page_directory_entry *pd = ppgtt->pdp.page_directory[pdpe];
+			struct i915_page_directory_entry *pd = pdp->page_directory[pdpe];
 			struct i915_page_table_entry *pt = pd->page_tables[pde];
 			struct page *page_table = pt->page;
 
@@ -708,16 +710,17 @@ static void gen8_free_page_tables(struct i915_page_directory_entry *pd, struct d
 static void gen8_ppgtt_unmap_pages(struct i915_hw_ppgtt *ppgtt)
 {
 	struct pci_dev *hwdev = ppgtt->base.dev->pdev;
+	struct i915_page_directory_pointer_entry *pdp = &ppgtt->pdp; /* FIXME: 48b */
 	int i, j;
 
-	for_each_set_bit(i, ppgtt->pdp.used_pdpes,
+	for_each_set_bit(i, pdp->used_pdpes,
 			I915_PDPES_PER_PDP(ppgtt->base.dev)) {
 		struct i915_page_directory_entry *pd;
 
-		if (WARN_ON(!ppgtt->pdp.page_directory[i]))
+		if (WARN_ON(!pdp->page_directory[i]))
 			continue;
 
-		pd = ppgtt->pdp.page_directory[i];
+		pd = pdp->page_directory[i];
 		if (!pd->daddr)
 			pci_unmap_page(hwdev, pd->daddr, PAGE_SIZE,
 					PCI_DMA_BIDIRECTIONAL);
@@ -743,15 +746,21 @@ static void gen8_ppgtt_free(struct i915_hw_ppgtt *ppgtt)
 {
 	int i;
 
-	for_each_set_bit(i, ppgtt->pdp.used_pdpes,
-				I915_PDPES_PER_PDP(ppgtt->base.dev)) {
-		if (WARN_ON(!ppgtt->pdp.page_directory[i]))
-			continue;
+	if (!USES_FULL_48BIT_PPGTT(ppgtt->base.dev)) {
+		for_each_set_bit(i, ppgtt->pdp.used_pdpes,
+				 I915_PDPES_PER_PDP(ppgtt->base.dev)) {
+			if (WARN_ON(!ppgtt->pdp.page_directory[i]))
+				continue;
 
-		gen8_free_page_tables(ppgtt->pdp.page_directory[i], ppgtt->base.dev);
-		unmap_and_free_pd(ppgtt->pdp.page_directory[i], ppgtt->base.dev);
+			gen8_free_page_tables(ppgtt->pdp.page_directory[i],
+					      ppgtt->base.dev);
+			unmap_and_free_pd(ppgtt->pdp.page_directory[i],
+					  ppgtt->base.dev);
+		}
+		unmap_and_free_pdp(&ppgtt->pdp, ppgtt->base.dev);
+	} else {
+		BUG(); /* to be implemented later */
 	}
-	unmap_and_free_pdp(&ppgtt->pdp, ppgtt->base.dev);
 }
 
 static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
@@ -765,7 +774,7 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
 
 /**
  * gen8_ppgtt_alloc_pagetabs() - Allocate page tables for VA range.
- * @ppgtt:	Master ppgtt structure.
+ * @vm:		Master vm structure.
  * @pd:		Page directory for this address range.
  * @start:	Starting virtual address to begin allocations.
  * @length	Size of the allocations.
@@ -781,12 +790,13 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
  *
  * Return: 0 if success; negative error code otherwise.
  */
-static int gen8_ppgtt_alloc_pagetabs(struct i915_hw_ppgtt *ppgtt,
+static int gen8_ppgtt_alloc_pagetabs(struct i915_address_space *vm,
 				     struct i915_page_directory_entry *pd,
 				     uint64_t start,
 				     uint64_t length,
 				     unsigned long *new_pts)
 {
+	struct drm_device *dev = vm->dev;
 	struct i915_page_table_entry *pt;
 	uint64_t temp;
 	uint32_t pde;
@@ -799,7 +809,7 @@ static int gen8_ppgtt_alloc_pagetabs(struct i915_hw_ppgtt *ppgtt,
 			continue;
 		}
 
-		pt = alloc_pt_single(ppgtt->base.dev);
+		pt = alloc_pt_single(dev);
 		if (IS_ERR(pt))
 			goto unwind_out;
 
@@ -811,14 +821,14 @@ static int gen8_ppgtt_alloc_pagetabs(struct i915_hw_ppgtt *ppgtt,
 
 unwind_out:
 	for_each_set_bit(pde, new_pts, GEN8_PDES_PER_PAGE)
-		unmap_and_free_pt(pd->page_tables[pde], ppgtt->base.dev);
+		unmap_and_free_pt(pd->page_tables[pde], dev);
 
 	return -ENOMEM;
 }
 
 /**
  * gen8_ppgtt_alloc_page_directories() - Allocate page directories for VA range.
- * @ppgtt:	Master ppgtt structure.
+ * @vm:		Master vm structure.
  * @pdp:	Page directory pointer for this address range.
  * @start:	Starting virtual address to begin allocations.
  * @length	Size of the allocations.
@@ -839,16 +849,17 @@ unwind_out:
  *
  * Return: 0 if success; negative error code otherwise.
  */
-static int gen8_ppgtt_alloc_page_directories(struct i915_hw_ppgtt *ppgtt,
+static int gen8_ppgtt_alloc_page_directories(struct i915_address_space *vm,
 				     struct i915_page_directory_pointer_entry *pdp,
 				     uint64_t start,
 				     uint64_t length,
 				     unsigned long *new_pds)
 {
+	struct drm_device *dev = vm->dev;
 	struct i915_page_directory_entry *pd;
 	uint64_t temp;
 	uint32_t pdpe;
-	size_t pdpes =  I915_PDPES_PER_PDP(ppgtt->base.dev);
+	size_t pdpes =  I915_PDPES_PER_PDP(vm->dev);
 
 	BUG_ON(!bitmap_empty(new_pds, pdpes));
 
@@ -859,7 +870,7 @@ static int gen8_ppgtt_alloc_page_directories(struct i915_hw_ppgtt *ppgtt,
 		if (pd)
 			continue;
 
-		pd = alloc_pd_single(ppgtt->base.dev);
+		pd = alloc_pd_single(dev);
 		if (IS_ERR(pd))
 			goto unwind_out;
 
@@ -871,7 +882,7 @@ static int gen8_ppgtt_alloc_page_directories(struct i915_hw_ppgtt *ppgtt,
 
 unwind_out:
 	for_each_set_bit(pdpe, new_pds, pdpes)
-		unmap_and_free_pd(pdp->page_directory[pdpe], ppgtt->base.dev);
+		unmap_and_free_pd(pdp->page_directory[pdpe], dev);
 
 	return -ENOMEM;
 }
@@ -926,13 +937,13 @@ err_out:
 	return -ENOMEM;
 }
 
-static int gen8_alloc_va_range(struct i915_address_space *vm,
-			       uint64_t start,
-			       uint64_t length)
+static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm,
+				    struct i915_page_directory_pointer_entry *pdp,
+				    uint64_t start,
+				    uint64_t length)
 {
-	struct i915_hw_ppgtt *ppgtt =
-		container_of(vm, struct i915_hw_ppgtt, base);
 	unsigned long *new_page_dirs, **new_page_tables;
+	struct drm_device *dev = vm->dev;
 	struct i915_page_directory_entry *pd;
 	const uint64_t orig_start = start;
 	const uint64_t orig_length = length;
@@ -961,17 +972,15 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
 		return ret;
 
 	/* Do the allocations first so we can easily bail out */
-	ret = gen8_ppgtt_alloc_page_directories(ppgtt, &ppgtt->pdp, start, length,
-					new_page_dirs);
+	ret = gen8_ppgtt_alloc_page_directories(vm, pdp, start, length, new_page_dirs);
 	if (ret) {
 		free_gen8_temp_bitmaps(new_page_dirs, new_page_tables, pdpes);
 		return ret;
 	}
 
-	/* For every page directory referenced, allocate page tables */
-	gen8_for_each_pdpe(pd, &ppgtt->pdp, start, length, temp, pdpe) {
+	gen8_for_each_pdpe(pd, pdp, start, length, temp, pdpe) {
 		bitmap_zero(new_page_tables[pdpe], GEN8_PDES_PER_PAGE);
-		ret = gen8_ppgtt_alloc_pagetabs(ppgtt, pd, start, length,
+		ret = gen8_ppgtt_alloc_pagetabs(vm, pd, start, length,
 						new_page_tables[pdpe]);
 		if (ret)
 			goto err_out;
@@ -980,10 +989,7 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
 	start = orig_start;
 	length = orig_length;
 
-	/* Allocations have completed successfully, so set the bitmaps, and do
-	 * the mappings. */
-	gen8_for_each_pdpe(pd, &ppgtt->pdp, start, length, temp, pdpe) {
-		gen8_ppgtt_pde_t *const page_directory = kmap_atomic(pd->page);
+	gen8_for_each_pdpe(pd, pdp, start, length, temp, pdpe) {
 		struct i915_page_table_entry *pt;
 		uint64_t pd_len = gen8_clamp_pd(start, length);
 		uint64_t pd_start = start;
@@ -1005,20 +1011,10 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
 
 			/* Our pde is now pointing to the pagetable, pt */
 			set_bit(pde, pd->used_pdes);
-
-			/* Map the PDE to the page table */
-			__gen8_do_map_pt(page_directory + pde, pt, vm->dev);
-
-			/* NB: We haven't yet mapped ptes to pages. At this
-			 * point we're still relying on insert_entries() */
 		}
 
-		if (!HAS_LLC(vm->dev))
-			drm_clflush_virt_range(page_directory, PAGE_SIZE);
-
-		kunmap_atomic(page_directory);
-
-		set_bit(pdpe, ppgtt->pdp.used_pdpes);
+		set_bit(pdpe, pdp->used_pdpes);
+		gen8_map_pagetable_range(pd, start, length, dev);
 	}
 
 	free_gen8_temp_bitmaps(new_page_dirs, new_page_tables, pdpes);
@@ -1027,16 +1023,36 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
 err_out:
 	while (pdpe--) {
 		for_each_set_bit(temp, new_page_tables[pdpe], GEN8_PDES_PER_PAGE)
-			unmap_and_free_pt(pd->page_tables[temp], vm->dev);
+			unmap_and_free_pt(pd->page_tables[temp], dev);
 	}
 
 	for_each_set_bit(pdpe, new_page_dirs, pdpes)
-		unmap_and_free_pd(ppgtt->pdp.page_directory[pdpe], vm->dev);
+		unmap_and_free_pd(pdp->page_directory[pdpe], dev);
 
 	free_gen8_temp_bitmaps(new_page_dirs, new_page_tables, pdpes);
 	return ret;
 }
 
+static int __noreturn gen8_alloc_va_range_4lvl(struct i915_address_space *vm,
+					       struct i915_pml4 *pml4,
+					       uint64_t start,
+					       uint64_t length)
+{
+	BUG(); /* to be implemented later */
+}
+
+static int gen8_alloc_va_range(struct i915_address_space *vm,
+			       uint64_t start, uint64_t length)
+{
+	struct i915_hw_ppgtt *ppgtt =
+		container_of(vm, struct i915_hw_ppgtt, base);
+
+	if (!USES_FULL_48BIT_PPGTT(vm->dev))
+		return gen8_alloc_va_range_3lvl(vm, &ppgtt->pdp, start, length);
+	else
+		return gen8_alloc_va_range_4lvl(vm, &ppgtt->pml4, start, length);
+}
+
 static void gen8_ppgtt_fini_common(struct i915_hw_ppgtt *ppgtt)
 {
 	unmap_and_free_pt(ppgtt->scratch_pd, ppgtt->base.dev);
@@ -1079,12 +1095,13 @@ static int gen8_aliasing_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
 {
 	struct drm_device *dev = ppgtt->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct i915_page_directory_pointer_entry *pdp = &ppgtt->pdp; /* FIXME: 48b */
 	struct i915_page_directory_entry *pd;
 	uint64_t temp, start = 0, size = dev_priv->gtt.base.total;
 	uint32_t pdpe;
 	int ret;
 
-	ret = gen8_ppgtt_init_common(ppgtt, dev_priv->gtt.base.total);
+	ret = gen8_ppgtt_init_common(ppgtt, size);
 	if (ret)
 		return ret;
 
@@ -1097,8 +1114,8 @@ static int gen8_aliasing_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
 		return ret;
 	}
 
-	gen8_for_each_pdpe(pd, &ppgtt->pdp, start, size, temp, pdpe)
-		gen8_map_pagetable_range(pd, start, size, ppgtt->base.dev);
+	gen8_for_each_pdpe(pd, pdp, start, size, temp, pdpe)
+		gen8_map_pagetable_range(pd, start, size, dev);
 
 	ppgtt->base.allocate_va_range = NULL;
 	ppgtt->base.clear_range = gen8_ppgtt_clear_range;
