[PATCH 10/10] mm: Use folio_next_pos()

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

This is one instruction more efficient than open-coding folio_pos() +
folio_size().  It's the equivalent of (x + y) << z rather than
x << z + y << z.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
---
 mm/shmem.c    | 2 +-
 mm/truncate.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index b9081b817d28..c819cecf1ed9 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1133,7 +1133,7 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
 	same_folio = (lstart >> PAGE_SHIFT) == (lend >> PAGE_SHIFT);
 	folio = shmem_get_partial_folio(inode, lstart >> PAGE_SHIFT);
 	if (folio) {
-		same_folio = lend < folio_pos(folio) + folio_size(folio);
+		same_folio = lend < folio_next_pos(folio);
 		folio_mark_dirty(folio);
 		if (!truncate_inode_partial_folio(folio, lstart, lend)) {
 			start = folio_next_index(folio);
diff --git a/mm/truncate.c b/mm/truncate.c
index 91eb92a5ce4f..a3d673533e32 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -387,7 +387,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
 	same_folio = (lstart >> PAGE_SHIFT) == (lend >> PAGE_SHIFT);
 	folio = __filemap_get_folio(mapping, lstart >> PAGE_SHIFT, FGP_LOCK, 0);
 	if (!IS_ERR(folio)) {
-		same_folio = lend < folio_pos(folio) + folio_size(folio);
+		same_folio = lend < folio_next_pos(folio);
 		if (!truncate_inode_partial_folio(folio, lstart, lend)) {
 			start = folio_next_index(folio);
 			if (same_folio)
-- 
2.47.2