1 files changed, 71 insertions, 85 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index b31b18058965..f56be5bc0861 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -34,6 +34,8 @@
 #include <drm/ttm/ttm_bo_driver.h>
 #include <drm/ttm/ttm_placement.h>
 #include <drm/drm_vma_manager.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_managed.h>
 #include <linux/mm.h>
 #include <linux/pfn_t.h>
 #include <linux/rbtree.h>
@@ -100,7 +102,7 @@ static unsigned long ttm_bo_io_mem_pfn(struct ttm_buffer_object *bo,
 	if (bdev->funcs->io_mem_pfn)
 		return bdev->funcs->io_mem_pfn(bo, page_offset);
 
-	return (bo->mem.bus.offset >> PAGE_SHIFT) + page_offset;
+	return (bo->resource->bus.offset >> PAGE_SHIFT) + page_offset;
 }
 
 /**
@@ -198,10 +200,10 @@ static vm_fault_t ttm_bo_vm_insert_huge(struct vm_fault *vmf,
 
 	/* Fault should not cross bo boundary. */
 	page_offset &= ~(fault_page_size - 1);
-	if (page_offset + fault_page_size > bo->mem.num_pages)
+	if (page_offset + fault_page_size > bo->resource->num_pages)
 		goto out_fallback;
 
-	if (bo->mem.bus.is_iomem)
+	if (bo->resource->bus.is_iomem)
 		pfn = ttm_bo_io_mem_pfn(bo, page_offset);
 	else
 		pfn = page_to_pfn(ttm->pages[page_offset]);
@@ -211,7 +213,7 @@ static vm_fault_t ttm_bo_vm_insert_huge(struct vm_fault *vmf,
 		goto out_fallback;
 
 	/* Check that memory is contiguous. */
-	if (!bo->mem.bus.is_iomem) {
+	if (!bo->resource->bus.is_iomem) {
 		for (i = 1; i < fault_page_size; ++i) {
 			if (page_to_pfn(ttm->pages[page_offset + i]) != pfn + i)
 				goto out_fallback;
@@ -297,7 +299,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 	if (unlikely(ret != 0))
 		return ret;
 
-	err = ttm_mem_io_reserve(bdev, &bo->mem);
+	err = ttm_mem_io_reserve(bdev, bo->resource);
 	if (unlikely(err != 0))
 		return VM_FAULT_SIGBUS;
 
@@ -306,11 +308,11 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 	page_last = vma_pages(vma) + vma->vm_pgoff -
 		drm_vma_node_start(&bo->base.vma_node);
 
-	if (unlikely(page_offset >= bo->mem.num_pages))
+	if (unlikely(page_offset >= bo->resource->num_pages))
 		return VM_FAULT_SIGBUS;
 
-	prot = ttm_io_prot(bo, &bo->mem, prot);
-	if (!bo->mem.bus.is_iomem) {
+	prot = ttm_io_prot(bo, bo->resource, prot);
+	if (!bo->resource->bus.is_iomem) {
 		struct ttm_operation_ctx ctx = {
 			.interruptible = false,
 			.no_wait_gpu = false,
@@ -335,7 +337,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 	 * first page.
 	 */
 	for (i = 0; i < num_prefault; ++i) {
-		if (bo->mem.bus.is_iomem) {
+		if (bo->resource->bus.is_iomem) {
 			pfn = ttm_bo_io_mem_pfn(bo, page_offset);
 		} else {
 			page = ttm->pages[page_offset];
@@ -357,12 +359,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 		 * at arbitrary times while the data is mmap'ed.
 		 * See vmf_insert_mixed_prot() for a discussion.
 		 */
-		if (vma->vm_flags & VM_MIXEDMAP)
-			ret = vmf_insert_mixed_prot(vma, address,
-						    __pfn_to_pfn_t(pfn, PFN_DEV),
-						    prot);
-		else
-			ret = vmf_insert_pfn_prot(vma, address, pfn, prot);
+		ret = vmf_insert_pfn_prot(vma, address, pfn, prot);
 
 		/* Never error on prefaulted PTEs */
 		if (unlikely((ret & VM_FAULT_ERROR))) {
@@ -380,19 +377,63 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 }
 EXPORT_SYMBOL(ttm_bo_vm_fault_reserved);
 
+static void ttm_bo_release_dummy_page(struct drm_device *dev, void *res)
+{
+	struct page *dummy_page = (struct page *)res;
+
+	__free_page(dummy_page);
+}
+
+vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+	struct drm_device *ddev = bo->base.dev;
+	vm_fault_t ret = VM_FAULT_NOPAGE;
+	unsigned long address;
+	unsigned long pfn;
+	struct page *page;
+
+	/* Allocate new dummy page to map all the VA range in this VMA to it*/
+	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+	if (!page)
+		return VM_FAULT_OOM;
+
+	/* Set the page to be freed using drmm release action */
+	if (drmm_add_action_or_reset(ddev, ttm_bo_release_dummy_page, page))
+		return VM_FAULT_OOM;
+
+	pfn = page_to_pfn(page);
+
+	/* Prefault the entire VMA range right away to avoid further faults */
+	for (address = vma->vm_start; address < vma->vm_end;
+	     address += PAGE_SIZE)
+		ret = vmf_insert_pfn_prot(vma, address, pfn, prot);
+
+	return ret;
+}
+EXPORT_SYMBOL(ttm_bo_vm_dummy_page);
+
 vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	pgprot_t prot;
 	struct ttm_buffer_object *bo = vma->vm_private_data;
+	struct drm_device *ddev = bo->base.dev;
 	vm_fault_t ret;
+	int idx;
 
 	ret = ttm_bo_vm_reserve(bo, vmf);
 	if (ret)
 		return ret;
 
 	prot = vma->vm_page_prot;
-	ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT, 1);
+	if (drm_dev_enter(ddev, &idx)) {
+		ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT, 1);
+		drm_dev_exit(idx);
+	} else {
+		ret = ttm_bo_vm_dummy_page(vmf, prot);
+	}
 	if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
 		return ret;
 
@@ -469,14 +510,14 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
 		 << PAGE_SHIFT);
 	int ret;
 
-	if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->mem.num_pages)
+	if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->resource->num_pages)
 		return -EIO;
 
 	ret = ttm_bo_reserve(bo, true, false, NULL);
 	if (ret)
 		return ret;
 
-	switch (bo->mem.mem_type) {
+	switch (bo->resource->mem_type) {
 	case TTM_PL_SYSTEM:
 		if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
 			ret = ttm_tt_swapin(bo->ttm);
@@ -508,33 +549,20 @@ static const struct vm_operations_struct ttm_bo_vm_ops = {
 	.access = ttm_bo_vm_access,
 };
 
-static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_device *bdev,
-						  unsigned long offset,
-						  unsigned long pages)
+int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
 {
-	struct drm_vma_offset_node *node;
-	struct ttm_buffer_object *bo = NULL;
-
-	drm_vma_offset_lock_lookup(bdev->vma_manager);
-
-	node = drm_vma_offset_lookup_locked(bdev->vma_manager, offset, pages);
-	if (likely(node)) {
-		bo = container_of(node, struct ttm_buffer_object,
-				  base.vma_node);
-		bo = ttm_bo_get_unless_zero(bo);
-	}
-
-	drm_vma_offset_unlock_lookup(bdev->vma_manager);
-
-	if (!bo)
-		pr_err("Could not find buffer object to map\n");
+	/* Enforce no COW since would have really strange behavior with it. */
+	if (is_cow_mapping(vma->vm_flags))
+		return -EINVAL;
 
-	return bo;
-}
+	ttm_bo_get(bo);
 
-static void ttm_bo_mmap_vma_setup(struct ttm_buffer_object *bo, struct vm_area_struct *vma)
-{
-	vma->vm_ops = &ttm_bo_vm_ops;
+	/*
+	 * Drivers may want to override the vm_ops field. Otherwise we
+	 * use TTM's default callbacks.
+	 */
+	if (!vma->vm_ops)
+		vma->vm_ops = &ttm_bo_vm_ops;
 
 	/*
 	 * Note: We're transferring the bo reference to
@@ -543,50 +571,8 @@ static void ttm_bo_mmap_vma_setup(struct ttm_buffer_object *bo, struct vm_area_s
 
 	vma->vm_private_data = bo;
 
-	/*
-	 * We'd like to use VM_PFNMAP on shared mappings, where
-	 * (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
-	 * but for some reason VM_PFNMAP + x86 PAT + write-combine is very
-	 * bad for performance. Until that has been sorted out, use
-	 * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
-	 */
-	vma->vm_flags |= VM_MIXEDMAP;
+	vma->vm_flags |= VM_PFNMAP;
 	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
-}
-
-int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
-		struct ttm_device *bdev)
-{
-	struct ttm_buffer_object *bo;
-	int ret;
-
-	if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET_START))
-		return -EINVAL;
-
-	bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
-	if (unlikely(!bo))
-		return -EINVAL;
-
-	if (unlikely(!bo->bdev->funcs->verify_access)) {
-		ret = -EPERM;
-		goto out_unref;
-	}
-	ret = bo->bdev->funcs->verify_access(bo, filp);
-	if (unlikely(ret != 0))
-		goto out_unref;
-
-	ttm_bo_mmap_vma_setup(bo, vma);
-	return 0;
-out_unref:
-	ttm_bo_put(bo);
-	return ret;
-}
-EXPORT_SYMBOL(ttm_bo_mmap);
-
-int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
-{
-	ttm_bo_get(bo);
-	ttm_bo_mmap_vma_setup(bo, vma);
 	return 0;
 }
 EXPORT_SYMBOL(ttm_bo_mmap_obj);