[PATCH] erofs: enable large folio in device-based mode

[Jingbo Xu]

Enable large folio in device-based mode. Then the radahead routine will
pass down large folio containing multiple pages.

Enable this feature for non-compressed format for now, until the
compression part supports large folio later.

Signed-off-by: Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx>
---
I have tested it under workload of Linux compiling. I know it's not a
perfect workload testing this feature, because large folio is less
likely hit in this case since source files are generally small. But I
indeed observed large folios (e.g. 16 pages) by peeking
readahead_count(rac) in erofs_readahead().
---
 fs/erofs/inode.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index ad2a82f2eb4c..e457b8a59ee7 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -295,6 +295,8 @@ static int erofs_fill_inode(struct inode *inode)
 		goto out_unlock;
 	}
 	inode->i_mapping->a_ops = &erofs_raw_access_aops;
+	if (!erofs_is_fscache_mode(inode->i_sb))
+		mapping_set_large_folios(inode->i_mapping);
 #ifdef CONFIG_EROFS_FS_ONDEMAND
 	if (erofs_is_fscache_mode(inode->i_sb))
 		inode->i_mapping->a_ops = &erofs_fscache_access_aops;
-- 
2.19.1.6.gb485710b