xnbd_mq: Remove empty allocation of piocb

Not used since we moved to iocb pool.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
xnbd: Use blk-mq preallocation for IO units

It is much better than maintaining io_u pool.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
xnbd: Allow session wait for all connections to establish wait to be interruptible

If the user is tired of waiting, allow him to interrupt the wait.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
xnbd: Fix possible race between xnbd connection send and xio event loop

Block-mq selects a HW context and then issue the request to the LLD (xnbd),
during that period until xnbd_transfer calls xio_send_request we might
preempt and migrate to a different CPU. Since the connection must be mutualy
exclusive with the connection event loop (under get_cpu) we must issue
the send under the connection of the current cpuid.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
raio_kutils: Reduce raio_u header size

We only need to reserve space for SUBMIT header, no need
for 512 bytes.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
xnbd: Increase queue depth to 256

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
xnbd_mq: Disable random contribution

This may help performance as we don't contribute to
the system entropy by disabling randomness.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>