diff options
| -rw-r--r-- | mm/page-writeback.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 24de8b65fdbd..99c24b1ec7cc 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -872,9 +872,10 @@ 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; if (wbc->nonblocking && bdi_write_congested(bdi)) { @@ -884,14 +885,19 @@ 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) && @@ -900,7 +906,6 @@ 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]; @@ -918,7 +923,11 @@ 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; @@ -949,13 +958,15 @@ 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->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |