From: Geliang Tang <[email protected]> This series (previously named "MPTCP support to NVMe over TCP") had three RFC versions sent to Hannes in May 2025, with subsequent revisions based on his input. Following that, I initiated the process of upstreaming the dependent "mptcp: implement .read_sock" series, which was merged into the Linux kernel in February 2026.
After several rounds of iteration on the MPTCP mailing list, this set addresses all the reviewer comments (including Sashiko's) and fixes the identified issues. This topic was presented as a discussion item at LSF/MM/BPF 2026. During the "NVMe over MPTCP" [1] discussion at the conference, it was concluded that MPTCP should be treated as a new transport type, rather than a TCP variant. A request will be submitted to the NVMe working group to officially allocate a transport value for MPTCP. This series runs without any user space changes (libnvme, nvme-cli). Later, MPTCP KTLS support will be added, and a follow-up series will be sent to enable TLS for NVMe over MPTCP. Based on NVMe Multipath and Block Multiqueue, each TCP queue is converted into one MPTCP queue. This is achieved by abstracting six socket helpers (set_nodelay, set_reuseaddr, no_linger, etc.) into per-transport structures. Inside each MPTCP queue, multiple subflows using different IP addresses aggregate multi-NIC bandwidth and provide fail-over resilience. Patch 10 demonstrates that with a single NVMe multipath configuration and four network interfaces, MPTCP achieves four times the bandwidth of TCP. Patch 11 demonstrates that with four NVMe multipath paths, using the round-robin I/O policy and a lossy four-interface environment, MPTCP still achieves four times the bandwidth of TCP. [1] https://lore.kernel.org/linux-nvme/[email protected]/ Cc: Hannes Reinecke <[email protected]> Cc: John Meneghini <[email protected]> Cc: Randy Jennings <[email protected]> Cc: Nilay Shroff <[email protected]> Co-developed-by: zhenwei pi <[email protected]> Signed-off-by: zhenwei pi <[email protected]> Co-developed-by: Hui Zhu <[email protected]> Signed-off-by: Hui Zhu <[email protected]> Co-developed-by: Gang Yan <[email protected]> Signed-off-by: Gang Yan <[email protected]> Signed-off-by: Geliang Tang <[email protected]> Geliang Tang (11): nvmet-tcp: define accept tcp_proto struct nvmet-tcp: implement accept mptcp proto nvmet-tcp: define listen socket ops nvmet-tcp: register target mptcp transport nvmet-tcp: implement mptcp listen socket ops nvme-fabrics: compare transport in ip_options_match nvme-tcp: define host tcp_proto struct nvme-tcp: register host mptcp transport nvme-tcp: implement host mptcp proto selftests: mptcp: add nvme over mptcp test selftests: mptcp: nvme: add iopolicy tests drivers/nvme/host/fabrics.c | 1 + drivers/nvme/host/tcp.c | 101 ++++- drivers/nvme/target/configfs.c | 1 + drivers/nvme/target/tcp.c | 128 +++++- include/linux/nvme.h | 1 + include/net/mptcp.h | 31 ++ net/mptcp/sockopt.c | 149 +++++++ tools/testing/selftests/net/mptcp/Makefile | 1 + tools/testing/selftests/net/mptcp/config | 8 + .../testing/selftests/net/mptcp/mptcp_lib.sh | 12 + .../testing/selftests/net/mptcp/mptcp_nvme.sh | 397 ++++++++++++++++++ 11 files changed, 813 insertions(+), 17 deletions(-) create mode 100755 tools/testing/selftests/net/mptcp/mptcp_nvme.sh -- 2.53.0
