>>>>> "Ilya" == Ilya Dryomov <idryomov@xxxxxxxxx> writes: Ilya, Ilya> could you please explain blk_integrity_revalidate() and Ilya> its GENHD_FL_UP check in particular? We have the queue, Ilya> bi->profile can't be NULL after blk_integrity_register(), and Ilya> since the latter "must" be used for registering the profile with Ilya> the block layer, wouldn't the following be sufficient for Ilya> blk_integrity users? IIrc, the FL_UP check fixed a registration problem in the nvme driver. The rationale behind revalidate was that we need to handle devices which lose the integrity capability at runtime (i.e. a integrity-enabled DM device is extended with a non-cable drive forcing the feature to be turned off). The clearing of the integrity profile is more important in that case than zapping the stable pages flag. But that was the original reason for not just ORing BDI_CAP_STABLE_WRITES. I don't have a huge problem with keeping stable pages on if a device suddenly stops being integrity capable. However, I'd like to understand your use case a bit better. Ilya> The alternative seems to be to set up a bogus Ilya> blk_integrity_profile (nop_profile won't do -- this one would have Ilya> to be truly bogus w/ NULL *_fn) under BLK_DEV_INTEGRITY ifdefs and Ilya> hope that nothing breaks. Can you point me to the relevant code on your end? Thanks, Martin -- Martin K. Petersen Oracle Linux Engineering
