From f7b68046873724129798c405e1a4e326b409c08f Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Wed, 6 Sep 2017 16:21:40 -0700
Subject: [PATCH] mm: use find_get_pages_range() in filemap_range_has_page()

We want only pages from given range in filemap_range_has_page(),
furthermore we want at most a single page.

So use find_get_pages_range() instead of pagevec_lookup() and remove
unnecessary code.

Link: http://lkml.kernel.org/r/20170726114704.7626-10-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/filemap.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 129883f160a7b..84617a05db50b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -393,8 +393,7 @@ bool filemap_range_has_page(struct address_space *mapping,
 {
 	pgoff_t index = start_byte >> PAGE_SHIFT;
 	pgoff_t end = end_byte >> PAGE_SHIFT;
-	struct pagevec pvec;
-	bool ret;
+	struct page *page;
 
 	if (end_byte < start_byte)
 		return false;
@@ -402,12 +401,10 @@ bool filemap_range_has_page(struct address_space *mapping,
 	if (mapping->nrpages == 0)
 		return false;
 
-	pagevec_init(&pvec, 0);
-	if (!pagevec_lookup(&pvec, mapping, &index, 1))
+	if (!find_get_pages_range(mapping, &index, end, 1, &page))
 		return false;
-	ret = (pvec.pages[0]->index <= end);
-	pagevec_release(&pvec);
-	return ret;
+	put_page(page);
+	return true;
 }
 EXPORT_SYMBOL(filemap_range_has_page);
 
-- 
2.30.2