X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=blobdiff_plain;f=mm%2Ffilemap.c;h=229481d258bc89f344a5dd7899f456353a13919d;hp=594d73fef8b43bae852f4f7ace1e8cfc46b23690;hb=312e9d2f7053f480627dcaf5e14f9cae78e3715a;hpb=6101cb7ea26efd4b6b4f15b4db707bb097cf97eb

diff --git a/mm/filemap.c b/mm/filemap.c
index 594d73fef8b4..229481d258bc 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -420,19 +420,17 @@ static void __filemap_fdatawait_range(struct address_space *mapping,
 		return;
 
 	pagevec_init(&pvec, 0);
-	while ((index <= end) &&
-			(nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
-			PAGECACHE_TAG_WRITEBACK,
-			min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1)) != 0) {
+	while (index <= end) {
 		unsigned i;
 
+		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index,
+				end, PAGECACHE_TAG_WRITEBACK, PAGEVEC_SIZE);
+		if (!nr_pages)
+			break;
+
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 
-			/* until radix tree lookup accepts end_index */
-			if (page->index > end)
-				continue;
-
 			wait_on_page_writeback(page);
 			ClearPageError(page);
 		}
@@ -1754,9 +1752,10 @@ repeat:
 EXPORT_SYMBOL(find_get_pages_contig);
 
 /**
- * find_get_pages_tag - find and return pages that match @tag
+ * find_get_pages_range_tag - find and return pages in given range matching @tag
  * @mapping:	the address_space to search
  * @index:	the starting page index
+ * @end:	The final page index (inclusive)
  * @tag:	the tag index
  * @nr_pages:	the maximum number of pages
  * @pages:	where the resulting pages are placed
@@ -1764,8 +1763,9 @@ EXPORT_SYMBOL(find_get_pages_contig);
  * Like find_get_pages, except we only return pages which are tagged with
  * @tag.   We update @index to index the next page for the traversal.
  */
-unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index,
-			int tag, unsigned int nr_pages, struct page **pages)
+unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index,
+			pgoff_t end, int tag, unsigned int nr_pages,
+			struct page **pages)
 {
 	struct radix_tree_iter iter;
 	void **slot;
@@ -1778,6 +1778,9 @@ unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index,
 	radix_tree_for_each_tagged(slot, &mapping->page_tree,
 				   &iter, *index, tag) {
 		struct page *head, *page;
+
+		if (iter.index > end)
+			break;
 repeat:
 		page = radix_tree_deref_slot(slot);
 		if (unlikely(!page))
@@ -1819,18 +1822,28 @@ repeat:
 		}
 
 		pages[ret] = page;
-		if (++ret == nr_pages)
-			break;
+		if (++ret == nr_pages) {
+			*index = pages[ret - 1]->index + 1;
+			goto out;
+		}
 	}
 
+	/*
+	 * We come here when we got at @end. We take care to not overflow the
+	 * index @index as it confuses some of the callers. This breaks the
+	 * iteration when there is page at index -1 but that is already broken
+	 * anyway.
+	 */
+	if (end == (pgoff_t)-1)
+		*index = (pgoff_t)-1;
+	else
+		*index = end + 1;
+out:
 	rcu_read_unlock();
 
-	if (ret)
-		*index = pages[ret - 1]->index + 1;
-
 	return ret;
 }
-EXPORT_SYMBOL(find_get_pages_tag);
+EXPORT_SYMBOL(find_get_pages_range_tag);
 
 /**
  * find_get_entries_tag - find and return entries that match @tag