This patch series implements an NVMe PCI endpoint driver that implements a PCIe NVMe controller for a local NVMe fabrics host controller. This series is based on the improved PCI endpoint API patches "Improve PCI memory mapping API" (see [1]). The first 3 patches of this series are changes to the NVMe target and fabrics code to facilitate reusing the NVMe code and an NVMe host controller from other (non NVMe) drivers. Patch 4 is the main patch which introduces the NVMe PCI endpoint driver. This patch commit message provides and overview of the driver design and operation. Finally, patch 5 adds documentation files to document the NVMe PCI endpoint function driver internals, provide a user guide explaning how to setup an NVMe PCI endpoint device and describe the NVMe endpoint function driver binding attributes. This driver has been extensively tested using a Radxa Rock5B board (rk3588 Arm SoC). Some tests have also been done using a Pine Rockpro64 board (however, this board does not support PCI DMA, leading to very poor performance). Using the Radxa Rock5b board and setting up a 4 queue-pairs controller with a null-blk block device loop target, performance was measured using fio as follows: +----------------------------------+------------------------+ | Workload | IOPS (BW) | +----------------------------------+------------------------+ | Rand read, 4KB, QD=1, 1 job | 7382 IOPS | | Rand read, 4KB, QD=32, 1 job | 45.5k IOPS | | Rand read, 4KB, QD=32, 4 jobs | 49.7k IOPS | | Rand read, 128KB, QD=32, 1 job | 10.0k IOPS (1.31 GB/s) | | Rand read, 128KB, QD=32, 4 jobs | 10.2k IOPS (1.33 GB/s) | | Seq read, 128KB, QD=32, 1 job | 1.28 GB/s | | Seq read, 512KB, QD=32, 1 job | 1.28 GB/s | | Rand write, 128KB, QD=32, 1 job | 8713 IOPS (1.14 GB/s) | | Rand write, 128KB, QD=32, 4 jobs | 8103 IOPS (1.06 GB/s) | | Seq write, 128KB, QD=32, 1 job | 8557 IOPS (1.12 GB/s) | | Seq write, 512KB, QD=32, 1 job | 2069 IOPS (1.08 GB/s) | +----------------------------------+------------------------+ These results use the default MDTS of the NVMe enpoint driver of 128 KB. Setting the NVMe endpoint device with a larger MDTS of 512 KB leads to improved maximum throughput of up to 2.4 GB/s (e.g. for the 512K random read workloads and sequential read workloads). The maximum IOPS achieved with this larger MDTS does not change significantly. This driver is not intended for production use but rather to be a playground for learning NVMe and NVMe over fabrics and exploring/testing new NVMe features while providing reasonably good performance. [1] https://lore.kernel.org/linux-pci/20241007040319.157412-1-dlemoal@xxxxxxxxxx/T/#t Damien Le Moal (5): nvmet: rename and move nvmet_get_log_page_len() nvmef: export nvmef_create_ctrl() nvmef: Introduce the NVME_OPT_HIDDEN_NS option PCI: endpoint: Add NVMe endpoint function driver PCI: endpoint: Document the NVMe endpoint function driver .../endpoint/function/binding/pci-nvme.rst | 34 + Documentation/PCI/endpoint/index.rst | 3 + .../PCI/endpoint/pci-nvme-function.rst | 151 + Documentation/PCI/endpoint/pci-nvme-howto.rst | 190 ++ MAINTAINERS | 9 + drivers/nvme/host/core.c | 17 +- drivers/nvme/host/fabrics.c | 11 +- drivers/nvme/host/fabrics.h | 5 + drivers/nvme/target/admin-cmd.c | 20 +- drivers/nvme/target/discovery.c | 4 +- drivers/nvme/target/nvmet.h | 3 - drivers/pci/endpoint/functions/Kconfig | 9 + drivers/pci/endpoint/functions/Makefile | 1 + drivers/pci/endpoint/functions/pci-epf-nvme.c | 2489 +++++++++++++++++ include/linux/nvme.h | 19 + 15 files changed, 2935 insertions(+), 30 deletions(-) create mode 100644 Documentation/PCI/endpoint/function/binding/pci-nvme.rst create mode 100644 Documentation/PCI/endpoint/pci-nvme-function.rst create mode 100644 Documentation/PCI/endpoint/pci-nvme-howto.rst create mode 100644 drivers/pci/endpoint/functions/pci-epf-nvme.c -- 2.46.2
