4.17-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
commit 15256f6cc4b44f2e70503758150267fd2a53c0d6 upstream.
Add an explicit check for QUEUE_FLAG_DAX to __bdev_dax_supported(). This
is needed for DM configurations where the first element in the dm-linear or
dm-stripe target supports DAX, but other elements do not. Without this
check __bdev_dax_supported() will pass for such devices, letting a
filesystem on that device mount with the DAX option.
Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Suggested-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Reviewed-by: Toshi Kani <toshi.kani@xxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dax/super.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -85,6 +85,7 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
bool __bdev_dax_supported(struct block_device *bdev, int blocksize)
{
struct dax_device *dax_dev;
+ struct request_queue *q;
pgoff_t pgoff;
int err, id;
void *kaddr;
@@ -97,6 +98,13 @@ bool __bdev_dax_supported(struct block_d
bdevname(bdev, buf));
return false;
}
+
+ q = bdev_get_queue(bdev);
+ if (!q || !blk_queue_dax(q)) {
+ pr_debug("%s: error: request queue doesn't support dax\n",
+ bdevname(bdev, buf));
+ return false;
+ }
err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff);
if (err) {
