From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: [PATCHv4 16/43] filemap: handle huge pages in filemap_fdatawait_range()
Date: Tue, 25 Oct 2016 03:13:15 +0300
Message-ID: <20161025001342.76126-17-kirill.shutemov@linux.intel.com>
References: <20161025001342.76126-1-kirill.shutemov@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
        Hugh Dickins <hughd@google.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Matthew Wilcox <willy@infradead.org>,
        Ross Zwisler <ross.zwisler@linux.intel.com>,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-block@vger.kernel.org,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: "Theodore Ts'o" <tytso@mit.edu>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        Jan Kara <jack@suse.com>,
        Andrew Morton <akpm@linux-foundation.org>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20161025001342.76126-1-kirill.shutemov@linux.intel.com>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: linux-ext4.vger.kernel.org

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 954720092cf8..ecf5c2dba3fb 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -509,9 +509,14 @@ 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();
-- 
2.9.3