e1228581b3
Shay Drory says: ==================== devlink: Add port function attribute to enable/disable Roce and migratable This series is a complete rewrite of the series "devlink: Add port function attribute to enable/disable roce" link: https://lore.kernel.org/netdev/20221102163954.279266-1-danielj@nvidia.com/ Currently mlx5 PCI VF and SF are enabled by default for RoCE functionality. And mlx5 PCI VF is disable by dafault for migratable functionality. Currently a user does not have the ability to disable RoCE for a PCI VF/SF device before such device is enumerated by the driver. User is also incapable to do such setting from smartnic scenario for a VF from the smartnic. Current 'enable_roce' device knob is limited to do setting only at driverinit time. By this time device is already created and firmware has already allocated necessary system memory for supporting RoCE. Also, Currently a user does not have the ability to enable migratable for a PCI VF. The above are a hyper visor level control, to set the functionality of devices passed through to guests. This is achieved by extending existing 'port function' object to control capabilities of a function. This enables users to control capability of the device before enumeration. Examples when user prefers to disable RoCE for a VF when using switchdev mode: $ devlink port show pci/0000:06:00.0/1 pci/0000:06:00.0/1: type eth netdev pf0vf0 flavour pcivf controller 0 pfnum 0 vfnum 0 external false splittable false function: hw_addr 00:00:00:00:00:00 roce enable $ devlink port function set pci/0000:06:00.0/1 roce disable $ devlink port show pci/0000:06:00.0/1 pci/0000:06:00.0/1: type eth netdev pf0vf0 flavour pcivf controller 0 pfnum 0 vfnum 0 external false splittable false function: hw_addr 00:00:00:00:00:00 roce disable FAQs: ----- 1. What does roce enable/disable do? Ans: It disables RoCE capability of the function before its enumerated, so when driver reads the capability from the device firmware, it is disabled. At this point RDMA stack will not be able to create UD, QP1, RC, XRC type of QPs. When RoCE is disabled, the GID table of all ports of the device is disabled in the device and software stack. 2. How is the roce 'port function' option different from existing devlink param? Ans: RoCE attribute at the port function level disables the RoCE capability at the specific function level; while enable_roce only does at the software level. 3. Why is this option for disabling only RoCE and not the whole RDMA device? Ans: Because user still wants to use the RDMA device for non RoCE commands in more memory efficient way. ==================== Link: https://lore.kernel.org/r/20221206185119.380138-1-shayd@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.