block: add special APIs for run-time disabling of discard and friends
Christoph Hellwig authored

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.
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarBart Van Assche <bvanassche@acm.org>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarJohn Garry <john.g.garry@oracle.com>
Reviewed-by: default avatarNitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-15-hch@lst.de

Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
73e3715e
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