[PATCH 12/16] squashfs: step squashfs_readpage_block() lookups by folio

[Tal Zussman]

Have squashfs_readpage_block() move on to the index after each folio it
looks up rather than to the next index, so it grabs a large folio once
instead of once per page.

squashfs only uses order-0 folios, so no functional change. This is a
step towards enabling large folios.

Signed-off-by: Tal Zussman <tz2294@xxxxxxxxxxxx>
---
 fs/squashfs/file_direct.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/squashfs/file_direct.c b/fs/squashfs/file_direct.c
index ef522923e6a9..110a5b14f9c4 100644
--- a/fs/squashfs/file_direct.c
+++ b/fs/squashfs/file_direct.c
@@ -44,7 +44,7 @@ int squashfs_readpage_block(struct folio *folio, u64 block, int bsize,
 		return res;
 
 	/* Try to grab all the folios covered by the Squashfs block */
-	for (i = 0, index = start_index; index <= end_index; index++) {
+	for (i = 0, index = start_index; index <= end_index;) {
 		struct folio *f;
 
 		if (index == folio->index)
@@ -54,8 +54,12 @@ int squashfs_readpage_block(struct folio *folio, u64 block, int bsize,
 					FGP_LOCK | FGP_CREAT | FGP_NOWAIT,
 					mapping_gfp_mask(folio->mapping));
 
-		if (IS_ERR(f))
+		if (IS_ERR(f)) {
+			index++;
 			continue;
+		}
+
+		index = folio_next_index(f);
 
 		if (folio_test_uptodate(f)) {
 			folio_unlock(f);

-- 
2.39.5