diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 9a73533..5dc37f0 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1027,6 +1027,9 @@
 	case I915_PARAM_CMD_PARSER_VERSION:
 		value = i915_cmd_parser_get_version();
 		break;
+	case I915_PARAM_HAS_COHERENT_PHYS_GTT:
+		value = 1;
+		break;
 	default:
 		DRM_DEBUG("Unknown parameter %d\n", param->param);
 		return -EINVAL;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index f830596..3df9ef3 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1957,10 +1957,10 @@
 	unsigned long user_pin_count;
 	struct drm_file *pin_filp;
 
-	/** for phy allocated objects */
-	struct drm_dma_handle *phys_handle;
-
 	union {
+		/** for phy allocated objects */
+		struct drm_dma_handle *phys_handle;
+
 		struct i915_gem_userptr {
 			uintptr_t ptr;
 			unsigned read_only :1;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 3e0cabe..86cf428 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -208,40 +208,137 @@
 	return 0;
 }
 
-static void i915_gem_object_detach_phys(struct drm_i915_gem_object *obj)
+static int
+i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 {
-	drm_dma_handle_t *phys = obj->phys_handle;
+	struct address_space *mapping = file_inode(obj->base.filp)->i_mapping;
+	char *vaddr = obj->phys_handle->vaddr;
+	struct sg_table *st;
+	struct scatterlist *sg;
+	int i;
 
-	if (!phys)
-		return;
+	if (WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
+		return -EINVAL;
 
-	if (obj->madv == I915_MADV_WILLNEED) {
+	for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
+		struct page *page;
+		char *src;
+
+		page = shmem_read_mapping_page(mapping, i);
+		if (IS_ERR(page))
+			return PTR_ERR(page);
+
+		src = kmap_atomic(page);
+		memcpy(vaddr, src, PAGE_SIZE);
+		drm_clflush_virt_range(vaddr, PAGE_SIZE);
+		kunmap_atomic(src);
+
+		page_cache_release(page);
+		vaddr += PAGE_SIZE;
+	}
+
+	i915_gem_chipset_flush(obj->base.dev);
+
+	st = kmalloc(sizeof(*st), GFP_KERNEL);
+	if (st == NULL)
+		return -ENOMEM;
+
+	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
+		kfree(st);
+		return -ENOMEM;
+	}
+
+	sg = st->sgl;
+	sg->offset = 0;
+	sg->length = obj->base.size;
+
+	sg_dma_address(sg) = obj->phys_handle->busaddr;
+	sg_dma_len(sg) = obj->base.size;
+
+	obj->pages = st;
+	obj->has_dma_mapping = true;
+	return 0;
+}
+
+static void
+i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj)
+{
+	int ret;
+
+	BUG_ON(obj->madv == __I915_MADV_PURGED);
+
+	ret = i915_gem_object_set_to_cpu_domain(obj, true);
+	if (ret) {
+		/* In the event of a disaster, abandon all caches and
+		 * hope for the best.
+		 */
+		WARN_ON(ret != -EIO);
+		obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU;
+	}
+
+	if (obj->madv == I915_MADV_DONTNEED)
+		obj->dirty = 0;
+
+	if (obj->dirty) {
 		struct address_space *mapping = file_inode(obj->base.filp)->i_mapping;
-		char *vaddr = phys->vaddr;
+		char *vaddr = obj->phys_handle->vaddr;
 		int i;
 
 		for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
-			struct page *page = shmem_read_mapping_page(mapping, i);
-			if (!IS_ERR(page)) {
-				char *dst = kmap_atomic(page);
-				memcpy(dst, vaddr, PAGE_SIZE);
-				drm_clflush_virt_range(dst, PAGE_SIZE);
-				kunmap_atomic(dst);
+			struct page *page;
+			char *dst;
 
-				set_page_dirty(page);
+			page = shmem_read_mapping_page(mapping, i);
+			if (IS_ERR(page))
+				continue;
+
+			dst = kmap_atomic(page);
+			drm_clflush_virt_range(vaddr, PAGE_SIZE);
+			memcpy(dst, vaddr, PAGE_SIZE);
+			kunmap_atomic(dst);
+
+			set_page_dirty(page);
+			if (obj->madv == I915_MADV_WILLNEED)
 				mark_page_accessed(page);
-				page_cache_release(page);
-			}
+			page_cache_release(page);
 			vaddr += PAGE_SIZE;
 		}
-		i915_gem_chipset_flush(obj->base.dev);
+		obj->dirty = 0;
 	}
 
-#ifdef CONFIG_X86
-	set_memory_wb((unsigned long)phys->vaddr, phys->size / PAGE_SIZE);
-#endif
-	drm_pci_free(obj->base.dev, phys);
-	obj->phys_handle = NULL;
+	sg_free_table(obj->pages);
+	kfree(obj->pages);
+
+	obj->has_dma_mapping = false;
+}
+
+static void
+i915_gem_object_release_phys(struct drm_i915_gem_object *obj)
+{
+	drm_pci_free(obj->base.dev, obj->phys_handle);
+}
+
+static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
+	.get_pages = i915_gem_object_get_pages_phys,
+	.put_pages = i915_gem_object_put_pages_phys,
+	.release = i915_gem_object_release_phys,
+};
+
+static int
+drop_pages(struct drm_i915_gem_object *obj)
+{
+	struct i915_vma *vma, *next;
+	int ret;
+
+	drm_gem_object_reference(&obj->base);
+	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link)
+		if (i915_vma_unbind(vma))
+			break;
+
+	ret = i915_gem_object_put_pages(obj);
+	drm_gem_object_unreference(&obj->base);
+
+	return ret;
 }
 
 int
@@ -249,9 +346,7 @@
 			    int align)
 {
 	drm_dma_handle_t *phys;
-	struct address_space *mapping;
-	char *vaddr;
-	int i;
+	int ret;
 
 	if (obj->phys_handle) {
 		if ((unsigned long)obj->phys_handle->vaddr & (align -1))
@@ -266,41 +361,19 @@
 	if (obj->base.filp == NULL)
 		return -EINVAL;
 
+	ret = drop_pages(obj);
+	if (ret)
+		return ret;
+
 	/* create a new object */
 	phys = drm_pci_alloc(obj->base.dev, obj->base.size, align);
 	if (!phys)
 		return -ENOMEM;
 
-	vaddr = phys->vaddr;
-#ifdef CONFIG_X86
-	set_memory_wc((unsigned long)vaddr, phys->size / PAGE_SIZE);
-#endif
-	mapping = file_inode(obj->base.filp)->i_mapping;
-	for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
-		struct page *page;
-		char *src;
-
-		page = shmem_read_mapping_page(mapping, i);
-		if (IS_ERR(page)) {
-#ifdef CONFIG_X86
-			set_memory_wb((unsigned long)phys->vaddr, phys->size / PAGE_SIZE);
-#endif
-			drm_pci_free(obj->base.dev, phys);
-			return PTR_ERR(page);
-		}
-
-		src = kmap_atomic(page);
-		memcpy(vaddr, src, PAGE_SIZE);
-		kunmap_atomic(src);
-
-		mark_page_accessed(page);
-		page_cache_release(page);
-
-		vaddr += PAGE_SIZE;
-	}
-
 	obj->phys_handle = phys;
-	return 0;
+	obj->ops = &i915_gem_phys_ops;
+
+	return i915_gem_object_get_pages(obj);
 }
 
 static int
@@ -311,6 +384,14 @@
 	struct drm_device *dev = obj->base.dev;
 	void *vaddr = obj->phys_handle->vaddr + args->offset;
 	char __user *user_data = to_user_ptr(args->data_ptr);
+	int ret;
+
+	/* We manually control the domain here and pretend that it
+	 * remains coherent i.e. in the GTT domain, like shmem_pwrite.
+	 */
+	ret = i915_gem_object_wait_rendering(obj, false);
+	if (ret)
+		return ret;
 
 	if (__copy_from_user_inatomic_nocache(vaddr, user_data, args->size)) {
 		unsigned long unwritten;
@@ -326,6 +407,7 @@
 			return -EFAULT;
 	}
 
+	drm_clflush_virt_range(vaddr, args->size);
 	i915_gem_chipset_flush(dev);
 	return 0;
 }
@@ -1046,11 +1128,6 @@
 	 * pread/pwrite currently are reading and writing from the CPU
 	 * perspective, requiring manual detiling by the client.
 	 */
-	if (obj->phys_handle) {
-		ret = i915_gem_phys_pwrite(obj, args, file);
-		goto out;
-	}
-
 	if (obj->tiling_mode == I915_TILING_NONE &&
 	    obj->base.write_domain != I915_GEM_DOMAIN_CPU &&
 	    cpu_write_needs_clflush(obj)) {
@@ -1060,8 +1137,12 @@
 		 * textures). Fallback to the shmem path in that case. */
 	}
 
-	if (ret == -EFAULT || ret == -ENOSPC)
-		ret = i915_gem_shmem_pwrite(dev, obj, args, file);
+	if (ret == -EFAULT || ret == -ENOSPC) {
+		if (obj->phys_handle)
+			ret = i915_gem_phys_pwrite(obj, args, file);
+		else
+			ret = i915_gem_shmem_pwrite(dev, obj, args, file);
+	}
 
 out:
 	drm_gem_object_unreference(&obj->base);
@@ -3509,7 +3590,7 @@
 	 * Stolen memory is always coherent with the GPU as it is explicitly
 	 * marked as wc by the system, or the system is cache-coherent.
 	 */
-	if (obj->stolen)
+	if (obj->stolen || obj->phys_handle)
 		return false;
 
 	/* If the GPU is snooping the contents of the CPU cache,
@@ -4471,8 +4552,6 @@
 		}
 	}
 
-	i915_gem_object_detach_phys(obj);
-
 	/* Stolen objects don't hold a ref, but do hold pin count. Fix that up
 	 * before progressing. */
 	if (obj->stolen)