[PATCH 24/35] mm: Use pagevec_lookup_range_tag() in write_cache_pages()

[Jan Kara]

Use pagevec_lookup_range_tag() in write_cache_pages() as it is
interested only in pages from given range. Remove unnecessary code
resulting from this.

Signed-off-by: Jan Kara <jack at suse.cz>
---
 mm/page-writeback.c | 20 ++------------------
 1 file changed, 2 insertions(+), 18 deletions(-)

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 143c1c25d680..c77c387465ec 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2194,30 +2194,14 @@ int write_cache_pages(struct address_space *mapping,
 	while (!done && (index <= end)) {
 		int i;
 
-		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
-			      min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
+		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
+				tag, PAGEVEC_SIZE);
 		if (nr_pages == 0)
 			break;
 
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 
-			/*
-			 * At this point, the page may be truncated or
-			 * invalidated (changing page->mapping to NULL), or
-			 * even swizzled back from swapper_space to tmpfs file
-			 * mapping. However, page->index will not change
-			 * because we have a reference on the page.
-			 */
-			if (page->index > end) {
-				/*
-				 * can't be range_cyclic (1st pass) because
-				 * end == -1 in that case.
-				 */
-				done = 1;
-				break;
-			}
-
 			done_index = page->index;
 
 			lock_page(page);
-- 
2.12.3