1BLK_CLONED_RQ_CHECK_(9)          Block Devices         BLK_CLONED_RQ_CHECK_(9)
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NAME

6       blk_cloned_rq_check_limits - Helper function to check a cloned request
7       for new the queue limits
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SYNOPSIS

10       int blk_cloned_rq_check_limits(struct request_queue * q,
11                                      struct request * rq);
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ARGUMENTS

14       q
15           the queue
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17       rq
18           the request being checked
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DESCRIPTION

21       rq may have been made based on weaker limitations of upper-level queues
22       in request stacking drivers, and it may violate the limitation of q.
23       Since the block layer and the underlying device driver trust rq after
24       it is inserted to q, it should be checked against q before the
25       insertion using this generic function.
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27       Request stacking drivers like request-based dm may change the queue
28       limits when retrying requests on other queues. Those requests need to
29       be checked against the new queue limits again during dispatch.
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32Kernel Hackers Manual 2.6.         June 2019           BLK_CLONED_RQ_CHECK_(9)
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