Use dax_is_supported() to validate whether the architecture has
virtually aliased data caches at mount time. Mount fails if dax=always
is requested as a mount option on an architecture which does not support
DAX.
This is relevant for architectures which require a dynamic check
to validate whether they have virtually aliased data caches.
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing
caches")
Signed-off-by: Mathieu Desnoyers <[email protected]>
Cc: "Theodore Ts'o" <[email protected]>
Cc: Andreas Dilger <[email protected]>
Cc: [email protected]
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Dan Williams <[email protected]>
Cc: Vishal Verma <[email protected]>
Cc: Dave Jiang <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Russell King <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
fs/ext4/super.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c5fcf377ab1f..f2c11ae3ec29 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4743,7 +4743,10 @@ static int ext4_check_feature_compatibility(struct
super_block *sb,
}
if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
- if (ext4_has_feature_inline_data(sb)) {
+ if (!dax_is_supported()) {
+ ext4_msg(sb, KERN_ERR, "DAX unsupported by
architecture.");
+ return -EINVAL;
+ } else if (ext4_has_feature_inline_data(sb)) {
ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
" that may contain inline data");
return -EINVAL;
--
2.39.2
