[PATCHv3 17/41] filemap: handle huge pages in filemap_fdatawait_range()

Kirill A. Shutemov
2016-09-15T11:54:59Z

We writeback whole huge page a time.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
mm/filemap.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/mm/filemap.c b/mm/filemap.c
index 05b42d3e5ed8..53da93156e60 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -372,9 +372,14 @@ static int __filemap_fdatawait_range(struct address_space *mapping,
if (page->index > end)
continue;

+ page = compound_head(page);
wait_on_page_writeback(page);
if (TestClearPageError(page))
ret = -EIO;
+ if (PageTransHuge(page)) {
+ index = page->index + HPAGE_PMD_NR;
+ i += index - pvec.pages[i]->index - 1;
+ }
}
pagevec_release(&pvec);
cond_resched();