1 files changed, 18 insertions, 7 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2970e35fd03..eb277bdd4c5 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -868,9 +868,10 @@ int write_cache_pages(struct address_space *mapping,
         int done = 0;
         struct pagevec pvec;
         int nr_pages;
+        pgoff_t uninitialized_var(writeback_index);
         pgoff_t index;
         pgoff_t end;            /* Inclusive */
-        int scanned = 0;
+        int cycled;
         int range_whole = 0;
         long nr_to_write = wbc->nr_to_write;
 
@@ -881,14 +882,19 @@ int write_cache_pages(struct address_space *mapping,
 
         pagevec_init(&pvec, 0);
         if (wbc->range_cyclic) {
-                index = mapping->writeback_index; /* Start from prev offset */
+                writeback_index = mapping->writeback_index; /* prev offset */
+                index = writeback_index;
+                if (index == 0)
+                        cycled = 1;
+                else
+                        cycled = 0;
                 end = -1;
         } else {
                 index = wbc->range_start >> PAGE_CACHE_SHIFT;
                 end = wbc->range_end >> PAGE_CACHE_SHIFT;
                 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
                         range_whole = 1;
-                scanned = 1;
+                cycled = 1; /* ignore range_cyclic tests */
         }
 retry:
         while (!done && (index <= end) &&
@@ -897,7 +903,6 @@ retry:
                                               min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
                 unsigned i;
 
-                scanned = 1;
                 for (i = 0; i < nr_pages; i++) {
                         struct page *page = pvec.pages[i];
 
@@ -915,7 +920,11 @@ retry:
                                 continue;
                         }
 
-                        if (!wbc->range_cyclic && page->index > end) {
+                        if (page->index > end) {
+                                /*
+                                 * can't be range_cyclic (1st pass) because
+                                 * end == -1 in that case.
+                                 */
                                 done = 1;
                                 unlock_page(page);
                                 continue;
@@ -946,13 +955,15 @@ retry:
                 pagevec_release(&pvec);
                 cond_resched();
         }
-        if (!scanned && !done) {
+        if (!cycled) {
                 /*
+                 * range_cyclic:
                  * We hit the last page and there is more work to be done: wrap
                  * back to the start of the file
                  */
-                scanned = 1;
+                cycled = 1;
                 index = 0;
+                end = writeback_index - 1;
                 goto retry;
         }
         if (!wbc->no_nrwrite_index_update) {