[SCSI] fusion - expander hotplug suport in mptsas module
This adds support for hot adding and removing
expanders, and its associated attached devices.
When there is a change in topology,
the fusion firmware sends the
MPI_EVENT_SAS_DISCOVERY event to the driver.
The driver will read firmware config pages
to determine what changes took place, and refresh
drivers view of the world stored in ioc->sas_topology.
Here is the details of the action the driver does:
(1) Expander Added : The mptsas_discovery_work
workqueue is called. Config pages read, and
ioc->sas_topology is refreshed. The sas_phy_add()
is called for each phy of the expander. The
expanders attached devices are added via
sas_rphy_add(). Added end devices are handled within
the MPT_ADD_DEVICE logic in mptsas_hotplug_work
workqueue.
(2) Expander Delete : The sas_rphy_delete() will be
called for the top most compenent of the parent that the
expander is attached to. The sas_rphy_delete call
will delete all the children phys, rphys, and end devices.
This is handled from mptsas_discovery_work workqueue.
Signed-off-by: Eric Moore <Eric.Moore@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2 files changed