Only the priv field of rnbd_dev_blk_io is used, so store the value of
that in bio->bi_private directly and remove the entire bio_set overhead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20220124091107.642561-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The memory mapped in process_rdma is contiguous, so there is no need
to loop over bio_add_page.  Remove rnbd_bio_map_kern and just open code
the bio allocation and mapping in the caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jack Wang <jinpu.wang@ionons.com>
Tested-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20220124091107.642561-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Since we always set bi_end_io after call rnbd_bio_map_kern, so the
setting in rnbd_bio_map_kern is redundant.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Acked-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The function only has one caller, so let's open code it in process_rdma.
Another bonus is we can avoid push/pop stack, since we need to pass 8
arguments to rnbd_dev_submit_io.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Acked-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This provides helper functions for IO submitting to block dev.

Link: https://lore.kernel.org/r/20200511135131.27580-22-danil.kipnis@cloud.ionos.com
Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>