[PATCH v2 3/5] dax: fix S_DAX definition

[Dan Williams]

Make sure S_DAX is defined in the CONFIG_FS_DAX=n + CONFIG_DEV_DAX=y
case. Otherwise vma_is_dax() may incorrectly return false in the
Device-DAX case.

Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap")
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 include/linux/fs.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 79c413985305..b2fa9b4c1e51 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1859,7 +1859,7 @@ struct super_operations {
 #define S_IMA		1024	/* Inode has an associated IMA struct */
 #define S_AUTOMOUNT	2048	/* Automount/referral quasi-directory */
 #define S_NOSEC		4096	/* no suid or xattr security attributes */
-#ifdef CONFIG_FS_DAX
+#if IS_ENABLED(CONFIG_FS_DAX) || IS_ENABLED(CONFIG_DEV_DAX)
 #define S_DAX		8192	/* Direct Access, avoiding the page cache */
 #else
 #define S_DAX		0	/* Make all the DAX code disappear */