Move the blk_mq_alloc_data stack allocation only into the branch
that actually needs it, and use rq->mq_hctx instead of data.hctx
to refer to the hctx.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211012104045.658051-3-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>