4.17-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ross Zwisler <[email protected]> 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 <[email protected]> Suggested-by: Mike Snitzer <[email protected]> Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support") Cc: [email protected] Acked-by: Dan Williams <[email protected]> Reviewed-by: Toshi Kani <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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) {
