blk_cloned_rq_check_limits — Helper function to check a cloned request for new the queue limits
int blk_cloned_rq_check_limits ( | struct request_queue * q, |
struct request * rq) ; |
rq
may have been made based on weaker limitations of upper-level queues
in request stacking drivers, and it may violate the limitation of q
.
Since the block layer and the underlying device driver trust rq
after it is inserted to q
, it should be checked against q
before
the insertion using this generic function.
Request stacking drivers like request-based dm may change the queue limits when retrying requests on other queues. Those requests need to be checked against the new queue limits again during dispatch.