This is the first stage of a RDMA stack upgrade introducing kernel
changes only based on Linux 5.7-rc1.
This patch is based on about four main areas of work:
- Update of the IB uobjects system:
- The memory holding so-called AH, CQ, PD, SRQ and UCONTEXT objects is now managed by ibcore. This also require some changes in the kernel verbs API. The updated verbs changes are typically about initialize and deinitialize objects, and remove allocation and free of memory.
- Update of the uverbs IOCTL framework:
- The parsing and handling of user-space commands has been completely refactored to integrate with the updated IB uobjects system.
- Various changes and updates to the generic uverbs interfaces in device drivers including the new uAPI surface.
- The mlx5_ib_devx.c in mlx5ib and related mlx5 core changes.
- The mlx4ib driver code has been updated with the minimum changes
- The mlx5ib driver code has been updated with the minimum changes
needed including DV support.
- All user-space facing APIs are backwards compatible after this change.
- All kernel-space facing RDMA APIs are backwards compatible after this change, with exception of ib_create_ah() and ib_destroy_ah() which takes a new flag.
- The "ib_device_ops" structure exist, but only contains the driver ID and some structure sizes.
Differences from Linux:
- Infiniband drivers must use the INIT_IB_DEVICE_OPS() macro to set the sizes needed for allocating various IB objects, when adding IB device instances.
- PRIV_NET_RAW is needed to use raw ethernet transmit features.
- PRIV_DRIVER is needed to use other privileged operations.
Based on upstream Linux, Torvalds (5.7-rc1):
MFC after: 1 week
Sponsored by: Mellanox Technologies // NVIDIA Networking