drm: nopage compat fixup for drm_vm

The kernel has removed nopage so move the old nopage codepaths into a compat vm file and switch to using the fault paths.

nopfn is on its way out in the future also, so we should switch to using fault
for that path as well soon

1 files changed, 61 insertions, 81 deletions

diff --git a/linux-core/drm_vm.c b/linux-core/drm_vm.c
index b85b4c13..6618c0ae 100644
--- a/linux-core/drm_vm.c
+++ b/linux-core/drm_vm.c
@@ -81,8 +81,9 @@ static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
 	return tmp;
 }
 
+#ifndef DRM_VM_NOPAGE
 /**
- * \c nopage method for AGP virtual memory.
+ * \c fault method for AGP virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
@@ -92,8 +93,7 @@ static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
  * map, get the page, increment the use count and return it.
  */
 #if __OS_HAS_AGP
-static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
-						unsigned long address)
+static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_file *priv = vma->vm_file->private_data;
 	struct drm_device *dev = priv->minor->dev;
@@ -105,19 +105,24 @@ static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 	 * Find the right map
 	 */
 	if (!drm_core_has_AGP(dev))
-		goto vm_nopage_error;
+		goto vm_fault_error;
 
 	if (!dev->agp || !dev->agp->cant_use_aperture)
-		goto vm_nopage_error;
+		goto vm_fault_error;
 
 	if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
-		goto vm_nopage_error;
+		goto vm_fault_error;
 
 	r_list = drm_hash_entry(hash, struct drm_map_list, hash);
 	map = r_list->map;
 
 	if (map && map->type == _DRM_AGP) {
-		unsigned long offset = address - vma->vm_start;
+		/*
+		 * Using vm_pgoff as a selector forces us to use this unusual
+		 * addressing scheme.
+		 */
+		unsigned long offset = (unsigned long)vmf->virtual_address -
+								vma->vm_start;
 		unsigned long baddr = map->offset + offset;
 		struct drm_agp_mem *agpmem;
 		struct page *page;
@@ -139,7 +144,7 @@ static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 		}
 
 		if (!agpmem)
-			goto vm_nopage_error;
+			goto vm_fault_error;
 
 		/*
 		 * Get the page, inc the use count, and return it
@@ -147,25 +152,21 @@ static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 		offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
 		page = virt_to_page(__va(agpmem->memory->memory[offset]));
 		get_page(page);
+		vmf->page = page;
 
-#if 0
-		/* page_count() not defined everywhere */
 		DRM_DEBUG
 		    ("baddr = 0x%lx page = 0x%p, offset = 0x%lx, count=%d\n",
 		     baddr, __va(agpmem->memory->memory[offset]), offset,
 		     page_count(page));
-#endif
-
-		return page;
+		return 0;
 	}
-      vm_nopage_error:
-	return NOPAGE_SIGBUS;	/* Disallow mremap */
+vm_fault_error:
+	return VM_FAULT_SIGBUS;	/* Disallow mremap */
 }
 #else				/* __OS_HAS_AGP */
-static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
-						unsigned long address)
+static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
-	return NOPAGE_SIGBUS;
+	return VM_FAULT_SIGBUS;
 }
 #endif				/* __OS_HAS_AGP */
 
@@ -179,29 +180,28 @@ static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
  * Get the mapping, find the real physical page to map, get the page, and
  * return it.
  */
-static __inline__ struct page *drm_do_vm_shm_nopage(struct vm_area_struct *vma,
-						    unsigned long address)
+static int drm_do_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_map *map = (struct drm_map *) vma->vm_private_data;
 	unsigned long offset;
 	unsigned long i;
 	struct page *page;
 
-	if (address > vma->vm_end)
-		return NOPAGE_SIGBUS;	/* Disallow mremap */
 	if (!map)
-		return NOPAGE_SIGBUS;	/* Nothing allocated */
+		return VM_FAULT_SIGBUS;	/* Nothing allocated */
 
-	offset = address - vma->vm_start;
+	offset = (unsigned long)vmf->virtual_address - vma->vm_start;
 	i = (unsigned long)map->handle + offset;
 	page = vmalloc_to_page((void *)i);
 	if (!page)
-		return NOPAGE_SIGBUS;
+		return VM_FAULT_SIGBUS;
 	get_page(page);
+	vmf->page = page;
 
-	DRM_DEBUG("0x%lx\n", address);
-	return page;
+	DRM_DEBUG("shm_fault 0x%lx\n", offset);
+	return 0;
 }
+#endif
 
 /**
  * \c close method for shared virtual memory.
@@ -283,8 +283,9 @@ static void drm_vm_shm_close(struct vm_area_struct *vma)
 	mutex_unlock(&dev->struct_mutex);
 }
 
+#ifndef DRM_VM_NOPAGE
 /**
- * \c nopage method for DMA virtual memory.
+ * \c fault method for DMA virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
@@ -292,8 +293,7 @@ static void drm_vm_shm_close(struct vm_area_struct *vma)
  *
  * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
  */
-static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
-						    unsigned long address)
+static int drm_do_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_file *priv = vma->vm_file->private_data;
 	struct drm_device *dev = priv->minor->dev;
@@ -303,24 +303,23 @@ static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
 	struct page *page;
 
 	if (!dma)
-		return NOPAGE_SIGBUS;	/* Error */
-	if (address > vma->vm_end)
-		return NOPAGE_SIGBUS;	/* Disallow mremap */
+		return VM_FAULT_SIGBUS;	/* Error */
 	if (!dma->pagelist)
-		return NOPAGE_SIGBUS;	/* Nothing allocated */
+		return VM_FAULT_SIGBUS;	/* Nothing allocated */
 
-	offset = address - vma->vm_start;	/* vm_[pg]off[set] should be 0 */
-	page_nr = offset >> PAGE_SHIFT;
+	offset = (unsigned long)vmf->virtual_address - vma->vm_start;	/* vm_[pg]off[set] should be 0 */
+	page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */
 	page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));
 
 	get_page(page);
+	vmf->page = page;
 
-	DRM_DEBUG("0x%lx (page %lu)\n", address, page_nr);
-	return page;
+	DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr);
+	return 0;
 }
 
 /**
- * \c nopage method for scatter-gather virtual memory.
+ * \c fault method for scatter-gather virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
@@ -328,8 +327,7 @@ static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
  *
  * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
  */
-static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
-						   unsigned long address)
+static int drm_do_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_map *map = (struct drm_map *) vma->vm_private_data;
 	struct drm_file *priv = vma->vm_file->private_data;
@@ -340,80 +338,62 @@ static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
 	unsigned long page_offset;
 	struct page *page;
 
-	DRM_DEBUG("\n");
 	if (!entry)
-		return NOPAGE_SIGBUS;	/* Error */
-	if (address > vma->vm_end)
-		return NOPAGE_SIGBUS;	/* Disallow mremap */
+		return VM_FAULT_SIGBUS;	/* Error */
 	if (!entry->pagelist)
-		return NOPAGE_SIGBUS;	/* Nothing allocated */
+		return VM_FAULT_SIGBUS;	/* Nothing allocated */
 
-	offset = address - vma->vm_start;
+	offset = (unsigned long)vmf->virtual_address - vma->vm_start;
 	map_offset = map->offset - (unsigned long)dev->sg->virtual;
 	page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
 	page = entry->pagelist[page_offset];
 	get_page(page);
+	vmf->page = page;
 
-	return page;
-}
-
-static struct page *drm_vm_nopage(struct vm_area_struct *vma,
-				  unsigned long address, int *type)
-{
-	if (type)
-		*type = VM_FAULT_MINOR;
-	return drm_do_vm_nopage(vma, address);
-}
-
-static struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
-				      unsigned long address, int *type)
-{
-	if (type)
-		*type = VM_FAULT_MINOR;
-	return drm_do_vm_shm_nopage(vma, address);
-}
-
-static struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
-				      unsigned long address, int *type)
-{
-	if (type)
-		*type = VM_FAULT_MINOR;
-	return drm_do_vm_dma_nopage(vma, address);
-}
-
-static struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
-				     unsigned long address, int *type)
-{
-	if (type)
-		*type = VM_FAULT_MINOR;
-	return drm_do_vm_sg_nopage(vma, address);
+	return 0;
 }
-
+#endif
 
 /** AGP virtual memory operations */
 static struct vm_operations_struct drm_vm_ops = {
+#ifdef DRM_VM_NOPAGE
 	.nopage = drm_vm_nopage,
+#else
+	.fault = drm_do_vm_fault,
+#endif
 	.open = drm_vm_open,
 	.close = drm_vm_close,
 };
 
 /** Shared virtual memory operations */
 static struct vm_operations_struct drm_vm_shm_ops = {
+#ifdef DRM_VM_NOPAGE
 	.nopage = drm_vm_shm_nopage,
+#else
+	.fault = drm_do_vm_shm_fault,
+#endif
 	.open = drm_vm_open,
 	.close = drm_vm_shm_close,
 };
 
 /** DMA virtual memory operations */
 static struct vm_operations_struct drm_vm_dma_ops = {
+#ifdef DRM_VM_NOPAGE
 	.nopage = drm_vm_dma_nopage,
+#else
+	.fault = drm_do_vm_dma_fault,
+#endif
 	.open = drm_vm_open,
 	.close = drm_vm_close,
 };
 
 /** Scatter-gather virtual memory operations */
 static struct vm_operations_struct drm_vm_sg_ops = {
+#ifdef DRM_VM_NOPAGE
 	.nopage = drm_vm_sg_nopage,
+#else
+	.fault = drm_do_vm_sg_fault,
+#endif
 	.open = drm_vm_open,
 	.close = drm_vm_close,
 };