Remove the use of reserved pages, and use locked pages instead.

Update compatibility for latest linux versions.

linux-core/drm_compat.c

@@ -54,19 +54,37 @@ static inline void change_pte_range(struct mm_struct *mm, pmd_t * pmd,
 				    unsigned long addr, unsigned long end)
 {
 	pte_t *pte;
+	struct page *page;
+	unsigned long pfn;
 
 	pte = pte_offset_map(pmd, addr);
 	do {
 		if (pte_present(*pte)) {
 			pte_t ptent;
-			ptep_get_and_clear(mm, addr, pte);
+			pfn = pte_pfn(*pte);
 			ptent = *pte;
-			lazy_mmu_prot_update(ptent);
-		} else {
 			ptep_get_and_clear(mm, addr, pte);
-		}
+			if (pfn_valid(pfn)) {
-		if (!pte_none(*pte)) {
+				page = pfn_to_page(pfn);
-		  DRM_ERROR("Ugh. Pte was presen\n");
+				if (atomic_add_negative(-1, &page->_mapcount)) {
+					if (page_test_and_clear_dirty(page))
+						set_page_dirty(page);
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,18)
+					dec_zone_page_state(page, NR_FILE_MAPPED);
+#else
+					dec_page_state(nr_mapped);
+#endif			
+				}
+
+				put_page(page);
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,15)
+				dec_mm_counter(mm, file_rss);
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
+				dec_mm_counter(mm, rss);
+#else
+				--mm->rss;
+#endif
+			}
 		}
 	} while (pte++, addr += PAGE_SIZE, addr != end);
 	pte_unmap(pte - 1);

linux-core/drm_ttm.c

@@ -199,6 +199,7 @@ static int unmap_vma_pages(drm_ttm_t * ttm, unsigned long page_offset,
 			      (page_offset << PAGE_SHIFT),
 			      entry->vma->vm_start +
 			      ((page_offset + num_pages) << PAGE_SHIFT));
+
 #if !defined(flush_tlb_mm) && defined(MODULE)
 		flush_tlb = 1;
 #endif
@@ -209,7 +210,7 @@ static int unmap_vma_pages(drm_ttm_t * ttm, unsigned long page_offset,
 #endif
 
 	for (cur_page = first_page; cur_page != last_page; ++cur_page) {
-		if (page_mapcount(*cur_page) != 0) {
+		if (page_mapped(*cur_page)) {
 			DRM_ERROR("Mapped page detected. Map count is %d\n",
 				  page_mapcount(*cur_page));
 			return -1;
@@ -239,6 +240,7 @@ int drm_destroy_ttm(drm_ttm_t * ttm)
 	}
 
 	DRM_DEBUG("Destroying a ttm\n");
+
 	if (ttm->be_list) {
 		list_for_each_safe(list, next, &ttm->be_list->head) {
 			drm_ttm_backend_list_t *entry =
@@ -262,7 +264,22 @@ int drm_destroy_ttm(drm_ttm_t * ttm)
 				do_tlbflush = 1;
 			}
 			if (*cur_page) {
-				ClearPageReserved(*cur_page);
+				ClearPageLocked(*cur_page);
+
+				/*
+				 * Debugging code. Remove if the error message never
+				 * shows up.
+				 */
+
+				if (page_count(*cur_page) != 1) {
+					DRM_ERROR("Erroneous page count. "
+						  "Leaking pages.\n");
+				}
+
+				/*
+				 * End debugging.
+				 */
+
 				__free_page(*cur_page);
 				--bm->cur_pages;
 			}
@@ -526,20 +543,7 @@ void drm_destroy_ttm_region(drm_ttm_backend_list_t * entry)
 
 	drm_unbind_ttm_region(entry);
 	if (be) {
-		be->clear(entry->be);
+		be->clear(be);
-#if 0 /* Hmm, Isn't this done in unbind? */
-		if (be->needs_cache_adjust(be)) {
-			int ret = drm_ttm_lock_mmap_sem(ttm);
-			drm_ttm_lock_mm(ttm, 0, 1);
-			unmap_vma_pages(ttm, entry->page_offset,
-					entry->num_pages);
-			drm_ttm_unlock_mm(ttm, 0, 1);
-			drm_set_caching(ttm, entry->page_offset,
-					entry->num_pages, 0, 1);
-			if (!ret)
-				drm_ttm_unlock_mm(ttm, 1, 0);
-		}
-#endif
 		be->destroy(be);
 	}
 	cur_page_flags = ttm->page_flags + entry->page_offset;
@@ -616,7 +620,7 @@ int drm_create_ttm_region(drm_ttm_t * ttm, unsigned long page_offset,
 				drm_destroy_ttm_region(entry);
 				return -ENOMEM;
 			}
-			SetPageReserved(*cur_page);
+			SetPageLocked(*cur_page);
 			++bm->cur_pages;
 		}
 	}

linux-core/drm_vm.c

@@ -276,16 +276,17 @@ static __inline__ struct page *drm_do_vm_ttm_nopage(struct vm_area_struct *vma,
 		++bm->cur_pages;
 		page = ttm->pages[page_offset] = 
 			alloc_page(GFP_KERNEL);
-		SetPageReserved(page);
 	}
 	if (!page) 
 		return NOPAGE_OOM;
 
+	SetPageLocked(page);
+	get_page(page);
+
 	default_prot = vm_get_page_prot(vma->vm_flags);
 
 	BUG_ON(page_flags & DRM_TTM_PAGE_UNCACHED);
 	vma->vm_page_prot = default_prot;
-
 	return page;
 }