1 files changed, 124 insertions, 49 deletions

diff --git a/drivers/char/drm/drm_memory.c b/drivers/char/drm/drm_memory.c
index 8074771e348f..7e3318e1d1c6 100644
--- a/drivers/char/drm/drm_memory.c
+++ b/drivers/char/drm/drm_memory.c
@@ -79,66 +79,72 @@ void *drm_realloc(void *oldpt, size_t oldsize, size_t size, int area)
 	return pt;
 }
 
-/**
- * Allocate pages.
- *
- * \param order size order.
- * \param area memory area. (Not used.)
- * \return page address on success, or zero on failure.
- *
- * Allocate and reserve free pages.
+#if __OS_HAS_AGP
+/*
+ * Find the drm_map that covers the range [offset, offset+size).
  */
-unsigned long drm_alloc_pages(int order, int area)
+static drm_map_t *drm_lookup_map(unsigned long offset,
+				 unsigned long size, drm_device_t * dev)
 {
-	unsigned long address;
-	unsigned long bytes = PAGE_SIZE << order;
-	unsigned long addr;
-	unsigned int sz;
-
-	address = __get_free_pages(GFP_KERNEL|__GFP_COMP, order);
-	if (!address)
-		return 0;
-
-	/* Zero */
-	memset((void *)address, 0, bytes);
-
-	/* Reserve */
-	for (addr = address, sz = bytes;
-	     sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
-		SetPageReserved(virt_to_page(addr));
+	struct list_head *list;
+	drm_map_list_t *r_list;
+	drm_map_t *map;
+
+	list_for_each(list, &dev->maplist->head) {
+		r_list = (drm_map_list_t *) list;
+		map = r_list->map;
+		if (!map)
+			continue;
+		if (map->offset <= offset
+		    && (offset + size) <= (map->offset + map->size))
+			return map;
 	}
-
-	return address;
+	return NULL;
 }
 
-/**
- * Free pages.
- *
- * \param address address of the pages to free.
- * \param order size order.
- * \param area memory area. (Not used.)
- *
- * Unreserve and free pages allocated by alloc_pages().
- */
-void drm_free_pages(unsigned long address, int order, int area)
+static void *agp_remap(unsigned long offset, unsigned long size,
+		       drm_device_t * dev)
 {
-	unsigned long bytes = PAGE_SIZE << order;
-	unsigned long addr;
-	unsigned int sz;
+	unsigned long *phys_addr_map, i, num_pages =
+	    PAGE_ALIGN(size) / PAGE_SIZE;
+	struct drm_agp_mem *agpmem;
+	struct page **page_map;
+	void *addr;
+
+	size = PAGE_ALIGN(size);
+
+#ifdef __alpha__
+	offset -= dev->hose->mem_space->start;
+#endif
+
+	for (agpmem = dev->agp->memory; agpmem; agpmem = agpmem->next)
+		if (agpmem->bound <= offset
+		    && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
+		    (offset + size))
+			break;
+	if (!agpmem)
+		return NULL;
 
-	if (!address)
-		return;
+	/*
+	 * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
+	 * the CPU do not get remapped by the GART.  We fix this by using the kernel's
+	 * page-table instead (that's probably faster anyhow...).
+	 */
+	/* note: use vmalloc() because num_pages could be large... */
+	page_map = vmalloc(num_pages * sizeof(struct page *));
+	if (!page_map)
+		return NULL;
 
-	/* Unreserve */
-	for (addr = address, sz = bytes;
-	     sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
-		ClearPageReserved(virt_to_page(addr));
-	}
+	phys_addr_map =
+	    agpmem->memory->memory + (offset - agpmem->bound) / PAGE_SIZE;
+	for (i = 0; i < num_pages; ++i)
+		page_map[i] = pfn_to_page(phys_addr_map[i] >> PAGE_SHIFT);
+	addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
+	vfree(page_map);
 
-	free_pages(address, order);
+	return addr;
 }
 
-#if __OS_HAS_AGP
 /** Wrapper around agp_allocate_memory() */
 DRM_AGP_MEM *drm_alloc_agp(drm_device_t * dev, int pages, u32 type)
 {
@@ -162,5 +168,74 @@ int drm_unbind_agp(DRM_AGP_MEM * handle)
 {
 	return drm_agp_unbind_memory(handle);
 }
+
+#else  /*  __OS_HAS_AGP  */
+
+static inline drm_map_t *drm_lookup_map(unsigned long offset,
+					unsigned long size, drm_device_t * dev)
+{
+	return NULL;
+}
+
+static inline void *agp_remap(unsigned long offset, unsigned long size,
+			      drm_device_t * dev)
+{
+	return NULL;
+}
+
 #endif				/* agp */
+
+void *drm_ioremap(unsigned long offset, unsigned long size,
+				drm_device_t * dev)
+{
+	if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture) {
+		drm_map_t *map = drm_lookup_map(offset, size, dev);
+
+		if (map && map->type == _DRM_AGP)
+			return agp_remap(offset, size, dev);
+	}
+	return ioremap(offset, size);
+}
+EXPORT_SYMBOL(drm_ioremap);
+
+#if 0
+void *drm_ioremap_nocache(unsigned long offset,
+					unsigned long size, drm_device_t * dev)
+{
+	if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture) {
+		drm_map_t *map = drm_lookup_map(offset, size, dev);
+
+		if (map && map->type == _DRM_AGP)
+			return agp_remap(offset, size, dev);
+	}
+	return ioremap_nocache(offset, size);
+}
+#endif  /*  0  */
+
+void drm_ioremapfree(void *pt, unsigned long size,
+				   drm_device_t * dev)
+{
+	/*
+	 * This is a bit ugly.  It would be much cleaner if the DRM API would use separate
+	 * routines for handling mappings in the AGP space.  Hopefully this can be done in
+	 * a future revision of the interface...
+	 */
+	if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture
+	    && ((unsigned long)pt >= VMALLOC_START
+		&& (unsigned long)pt < VMALLOC_END)) {
+		unsigned long offset;
+		drm_map_t *map;
+
+		offset = drm_follow_page(pt) | ((unsigned long)pt & ~PAGE_MASK);
+		map = drm_lookup_map(offset, size, dev);
+		if (map && map->type == _DRM_AGP) {
+			vunmap(pt);
+			return;
+		}
+	}
+
+	iounmap(pt);
+}
+EXPORT_SYMBOL(drm_ioremapfree);
+
 #endif				/* debug_memory */