nvme-rdma: don't complete requests before a send work request has completed

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In order to guarantee that the HCA will never get an access violation
(either from invalidated rkey or from iommu) when retrying a send
operation we must complete a request only when both send completion and
the nvme cqe has arrived. We need to set the send/recv completions flags
atomically because we might have more than a single context accessing the
request concurrently (one is cq irq-poll context and the other is
user-polling used in IOCB_HIPRI).

Only then we are safe to invalidate the rkey (if needed), unmap the host
buffers, and complete the IO.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

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Sagi Grimberg 2017-11-23 17:35:22 +02:00 • committed by Christoph Hellwig

parent b4b591c87f

commit 4af7f7ff92

1 changed files with 24 additions and 4 deletions

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drivers/nvme/host/rdma.c

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