From d6712eefc77e58a8625dc3f4598369085c824d5c Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Sun, 20 Sep 2020 08:54:42 -0700 Subject: dm: Call proper helper to determine dax support commit e2ec5128254518cae320d5dc631b71b94160f663 upstream. DM was calling generic_fsdax_supported() to determine whether a device referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that they don't have to duplicate common generic checks. High level code should call dax_supported() helper which that calls into appropriate helper for the particular device. This problem manifested itself as kernel messages: dm-3: error: dax access failed (-95) when lvm2-testsuite run in cases where a DM device was stacked on top of another DM device. Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices") Cc: Tested-by: Adrian Huang Signed-off-by: Jan Kara Acked-by: Mike Snitzer Reported-by: kernel test robot Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- drivers/dax/super.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/dax/super.c') diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 26a654dbc69a..b93685288187 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -318,11 +318,15 @@ EXPORT_SYMBOL_GPL(dax_direct_access); bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev, int blocksize, sector_t start, sector_t len) { + if (!dax_dev) + return false; + if (!dax_alive(dax_dev)) return false; return dax_dev->ops->dax_supported(dax_dev, bdev, blocksize, start, len); } +EXPORT_SYMBOL_GPL(dax_supported); size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i) -- cgit v1.2.3