RDMA/device: Provide APIs from the core code to help unregistration

Browse source

These APIs are intended to support drivers that exist outside the usual
driver core probe()/remove() callbacks. Normally the driver core will
prevent remove() from running concurrently with probe(), once this safety
is lost drivers need more support to get the locking and lifetimes right.

ib_unregister_driver() is intended to be used during module_exit of a
driver using these APIs. It unregisters all the associated ib_devices.

ib_unregister_device_and_put() is to be used by a driver-specific removal
function (ie removal by name, removal from a netdev notifier, removal from
netlink)

ib_unregister_queued() is to be used from netdev notifier chains where
RTNL is held.

The locking is tricky here since once things become async it is possible
to race unregister with registration. This is largely solved by relying on
the registration refcount, unregistration will only ever work on something
that has a positive registration refcount - and then an unregistration
mutex serializes all competing unregistrations of the same device.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

...

This commit is contained in:

Jason Gunthorpe 2019-02-12 21:12:53 -07:00

parent 4c173f596b

commit d0899892ed

2 changed files with 217 additions and 36 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

242

drivers/infiniband/core/device.c

View file

11

include/rdma/ib_verbs.h

View file