[PATCH 14/14] block: add special APIs for run-time disabling of discard and friends

[Martin K. Petersen]

Christoph,

> A few drivers optimistically try to support discard, write zeroes and
> secure erase and disable the features from the I/O completion handler
> if the hardware can't support them. This disable can't be done using
> the atomic queue limits API because the I/O completion handlers can't
> take sleeping locks or freeze the queue. Keep the existing clearing of
> the relevant field to zero, but replace the old blk_queue_max_* APIs
> with new disable APIs that force the value to 0.

Reviewed-by: Martin K. Petersen <martin.petersen at oracle.com>

-- 
Martin K. Petersen	Oracle Linux Engineering