From 2361db89aaadfb671db6911b0063e01ec8922c28 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 9 Mar 2021 17:43:38 -0800 Subject: libnvdimm: Notify disk drivers to revalidate region read-only Previous kernels allowed the BLKROSET to override the disk's read-only status. With that situation fixed the pmem driver needs to rely on notification events to reevaluate the disk read-only status after the host region has been marked read-write. Recall that when libnvdimm determines that the persistent memory has lost persistence (for example lack of energy to flush from DRAM to FLASH on an NVDIMM-N device) it marks the region read-only, but that state can be overridden by the user via: echo 0 > /sys/bus/nd/devices/regionX/read_only ...to date there is no notification that the region has restored persistence, so the user override is the only recovery. Fixes: 52f019d43c22 ("block: add a hard-readonly flag to struct gendisk") Reported-by: kernel test robot Reported-by: Vishal Verma Tested-by: Vishal Verma Reviewed-by: Christoph Hellwig Cc: Christoph Hellwig Cc: Ming Lei Cc: Martin K. Petersen Cc: Hannes Reinecke Cc: Jens Axboe Link: https://lore.kernel.org/r/161534060720.528671.2341213328968989192.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams --- include/linux/nd.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/nd.h') diff --git a/include/linux/nd.h b/include/linux/nd.h index cec526c8043d..ee9ad76afbba 100644 --- a/include/linux/nd.h +++ b/include/linux/nd.h @@ -11,6 +11,7 @@ enum nvdimm_event { NVDIMM_REVALIDATE_POISON, + NVDIMM_REVALIDATE_REGION, }; enum nvdimm_claim_class { -- cgit v1.2.3-58-ga151