[v5,0/2] Dynamic rdma link creation

Message

Steve Wise Nov. 30, 2018, 10 p.m. UTC

NOTE: v5 is just a reposting of v4 with the patch dates updated so they
work right in patchworks.

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This series enables creating soft rdma links dynamically using netlink
messages.  The user 'rdma' command [1] will be enhanced to send these new
messages.

Note there is at least one outstanding issue:  the rdma-core requires
RXE links to be named "rxe*" or it fails to associate an rxe uverbs
driver with the rxe provider.  This, however, can be addressed
in a subsequent series.

[1] rdma tool support (work-in-progress):
https://github.com/larrystevenwise/iproute2/tree/wip/newlink

Changes since V3:
- link_ops mutex replaced with rwsem
- save link_ops pointer in ib_device struct to be used when deleting
  a link
- only require the device index from userland for DELLINK operations
- pass struct ib_device pointer to drivers for dellink()

Changes since V2:
- removed unneeded enum value assignment
- removed gotos where there was no unwind logic
- protect get and use of link_ops with mutex

Changes since V1:
- rebased on for-next branch of linux-rdma repo
- removed 2 pr_debug()s
- validate string lengths in nldev_newlink()/nldev_dellink()
- don't allow '%' in ibdev names
- make all string parameters const char * in rdma_link_ops
- simplified the request_module logic in nldev_newlink()
- add leon's reviewed-by tag.

Changes since RFC:
- rebased on top of leon's and jason's device name work
- request module load if the link ops aren't found
- detect duplicate link ops adds
- const char * changes
- use the RDMA_NLDEV open enum values

Steve Wise (2):
  RDMA/Core: add RDMA_NLDEV_CMD_NEWLINK/DELLINK support
  rdma_rxe: use netlink messages to add/delete links

 drivers/infiniband/core/nldev.c       | 139 ++++++++++++++++++++++++++++++++++
 drivers/infiniband/sw/rxe/rxe.c       |  62 ++++++++++++++-
 drivers/infiniband/sw/rxe/rxe.h       |   2 +-
 drivers/infiniband/sw/rxe/rxe_net.c   |   4 +-
 drivers/infiniband/sw/rxe/rxe_net.h   |   2 +-
 drivers/infiniband/sw/rxe/rxe_sysfs.c |   6 +-
 drivers/infiniband/sw/rxe/rxe_verbs.c |   4 +-
 drivers/infiniband/sw/rxe/rxe_verbs.h |   2 +-
 include/rdma/ib_verbs.h               |   2 +
 include/rdma/rdma_netlink.h           |  13 ++++
 include/uapi/rdma/rdma_netlink.h      |  11 ++-
 11 files changed, 233 insertions(+), 14 deletions(-)