iomap: Use folio_next_pos()

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>
Link: https://patch.msgid.link/20251024170822.1427218-8-willy@infradead.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: linux-xfs@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 8b847a1e27f13eba67eb306a1d648ea2e19e587b..32a27f36372d7357d977a71d3c1ed4c6247fcaf8 100644 (file)
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -707,7 +707,7 @@ static int __iomap_write_begin(const struct iomap_iter *iter,
         * are not changing pagecache contents.
         */
        if (!(iter->flags & IOMAP_UNSHARE) && pos <= folio_pos(folio) &&
-           pos + len >= folio_pos(folio) + folio_size(folio))
+           pos + len >= folio_next_pos(folio))
                return 0;
 
        ifs = ifs_alloc(iter->inode, folio, iter->flags);
@@ -1097,8 +1097,7 @@ static void iomap_write_delalloc_ifs_punch(struct inode *inode,
        if (!ifs)
                return;
 
-       last_byte = min_t(loff_t, end_byte - 1,
-                       folio_pos(folio) + folio_size(folio) - 1);
+       last_byte = min_t(loff_t, end_byte - 1, folio_next_pos(folio) - 1);
        first_blk = offset_in_folio(folio, start_byte) >> blkbits;
        last_blk = offset_in_folio(folio, last_byte) >> blkbits;
        for (i = first_blk; i <= last_blk; i++) {
@@ -1129,8 +1128,7 @@ static void iomap_write_delalloc_punch(struct inode *inode, struct folio *folio,
         * Make sure the next punch start is correctly bound to
         * the end of this data range, not the end of the folio.
         */
-       *punch_start_byte = min_t(loff_t, end_byte,
-                               folio_pos(folio) + folio_size(folio));
+       *punch_start_byte = min_t(loff_t, end_byte, folio_next_pos(folio));
 }
 
 /*
@@ -1170,7 +1168,7 @@ static void iomap_write_delalloc_scan(struct inode *inode,
                                start_byte, end_byte, iomap, punch);
 
                /* move offset to start of next folio in range */
-               start_byte = folio_pos(folio) + folio_size(folio);
+               start_byte = folio_next_pos(folio);
                folio_unlock(folio);
                folio_put(folio);
        }