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 <mathieu.desnoy...@efficios.com>
Cc: "Theodore Ts'o" <ty...@mit.edu>
Cc: Andreas Dilger <adilger.ker...@dilger.ca>
Cc: linux-e...@vger.kernel.org
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: linux...@kvack.org
Cc: linux-a...@vger.kernel.org
Cc: Dan Williams <dan.j.willi...@intel.com>
Cc: Vishal Verma <vishal.l.ve...@intel.com>
Cc: Dave Jiang <dave.ji...@intel.com>
Cc: Matthew Wilcox <wi...@infradead.org>
Cc: Arnd Bergmann <a...@arndb.de>
Cc: Russell King <li...@armlinux.org.uk>
Cc: nvd...@lists.linux.dev
Cc: linux-...@vger.kernel.org
Cc: linux-fsde...@vger.kernel.org
---
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
