TCP transport binding for NVMe over Fabrics

This patch set implements the NVMe over Fabrics TCP host and the target drivers. Now NVMe over Fabrics can run on every Ethernet port in the world. The implementation conforms to NVMe over Fabrics 1.1 specification (which will include already publicly available NVMe/TCP transport binding, TP 8000).

The host driver hooks into the NVMe host stack and implements the TCP transport binding for NVMe over Fabrics. The NVMe over Fabrics TCP host driver is responsible for establishing a NVMe/TCP connection, TCP event and error handling and data-plane messaging and stream processing.

The target driver hooks into the NVMe target core stack and implements the TCP transport binding. The NVMe over Fabrics target driver is responsible for accepting and establishing NVMe/TCP connections, TCP event and error handling, and data-plane messaging and stream processing.

The implementation of both the host and target are fairly simple and straight-forward. Every NVMe queue is backed by a TCP socket that provides us reliable, in-order delivery of fabrics capsules and/or data.

All NVMe queues are sharded over a private bound workqueue such that we always have a single context handling the byte stream and we don't need to worry about any locking/serialization. In addition, close attention was paid to a completely non-blocking data plane to minimize context switching and/or unforced scheduling.

I piggybacked nvme-cli patches to the set for completeness.

Also, @netdev mailing list is cc'd as this patch set contains generic helpers for online digest calculation (patches 1-3).

The patchset structure:
- patches 1-3 adds a helper for digest calculation online with data placement
- patches 4-8 are preparatory patches for NVMe/TCP
- patches 9-11 implements NVMe/TCP
- patches 12-14 are nvme-cli additions for NVMe/TCP

Thanks to the members of the Fabrics Linux Driver team that helped development, testing and benchmarking this work.

Gitweb code is available at:

git://git.infradead.org/nvme.git nvme-tcp

Sagi Grimberg (11):
ath6kl: add ath6kl_ prefix to crypto_type
iov_iter: introduce hash_and_copy iter helpers
datagram: introduce skb_copy_and_hash_datagram_iter helper
nvme-core: add work elements to struct nvme_ctrl
nvmet: Add install_queue callout
nvmet: allow configfs tcp trtype configuration
nvme-fabrics: allow user passing header digest
nvme-fabrics: allow user passing data digest
nvme-tcp: Add protocol header
nvmet-tcp: add NVMe over TCP target driver
nvme-tcp: add NVMe over TCP host driver

 drivers/net/wireless/ath/ath6kl/cfg80211.c |    2 +-
 drivers/net/wireless/ath/ath6kl/common.h   |    2 +-
 drivers/net/wireless/ath/ath6kl/wmi.c      |    6 +-
 drivers/net/wireless/ath/ath6kl/wmi.h      |    6 +-
 drivers/nvme/host/Kconfig                  |   15 +
 drivers/nvme/host/Makefile                 |    3 +
 drivers/nvme/host/fabrics.c                |   10 +
 drivers/nvme/host/fabrics.h                |    4 +
 drivers/nvme/host/fc.c                     |   18 +-
 drivers/nvme/host/nvme.h                   |    2 +
 drivers/nvme/host/rdma.c                   |   19 +-
 drivers/nvme/host/tcp.c                    | 2305 ++++++++++++++++++++
 drivers/nvme/target/Kconfig                |   10 +
 drivers/nvme/target/Makefile               |    2 +
 drivers/nvme/target/configfs.c             |    1 +
 drivers/nvme/target/fabrics-cmd.c          |    9 +
 drivers/nvme/target/nvmet.h                |    1 +
 drivers/nvme/target/tcp.c                  | 1746 +++++++++++++++
 include/linux/nvme-tcp.h                   |  189 ++
 include/linux/nvme.h                       |    1 +
 include/linux/skbuff.h                     |    3 +
 include/linux/uio.h                        |    5 +
 lib/iov_iter.c                             |   31 +
 net/core/datagram.c                        |   90 +
 24 files changed, 4451 insertions(+), 29 deletions(-)
 create mode 100644 drivers/nvme/host/tcp.c
 create mode 100644 drivers/nvme/target/tcp.c
 create mode 100644 include/linux/nvme-tcp.h

2.17.1