diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 2970e35fd03f0fb6c3f178eca78b30166eeb6450..eb277bdd4c5d7b9a74b5588b12e7bcd0c53ea5b5 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 @@ int write_cache_pages(struct address_space *mapping, 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 @@ int write_cache_pages(struct address_space *mapping, 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 @@ int write_cache_pages(struct address_space *mapping, 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) {