hugetlbfs: use pagevec_lookup_range() in remove_inode_hugepages()

We want only pages from given range in remove_inode_hugepages().  Use
pagevec_lookup_range() instead of pagevec_lookup().

Link: http://lkml.kernel.org/r/20170726114704.7626-8-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nadia Yvette Chambers <nyc@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hugetlbfs/inode.c

@@ -403,7 +403,6 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
 	struct pagevec pvec;
 	pgoff_t next, index;
 	int i, freed = 0;
-	long lookup_nr = PAGEVEC_SIZE;
 	bool truncate_op = (lend == LLONG_MAX);
 
 	memset(&pseudo_vma, 0, sizeof(struct vm_area_struct));
@@ -411,31 +410,18 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
 	pagevec_init(&pvec, 0);
 	next = start;
 	while (next < end) {
-		/*
-		 * Don't grab more pages than the number left in the range.
-		 */
-		if (end - next < lookup_nr)
-			lookup_nr = end - next;
-
 		/*
 		 * When no more pages are found, we are done.
 		 */
-		if (!pagevec_lookup(&pvec, mapping, &next, lookup_nr))
+		if (!pagevec_lookup_range(&pvec, mapping, &next, end - 1,
+					  PAGEVEC_SIZE))
 			break;
 
 		for (i = 0; i < pagevec_count(&pvec); ++i) {
 			struct page *page = pvec.pages[i];
 			u32 hash;
 
-			/*
-			 * The page (index) could be beyond end.  This is
-			 * only possible in the punch hole case as end is
-			 * max page offset in the truncate case.
-			 */
 			index = page->index;
-			if (index >= end)
-				break;
-
 			hash = hugetlb_fault_mutex_hash(h, current->mm,
 							&pseudo_vma,
 							mapping, index, 0);