This directory is added only for the master -- slaves do not have it.
The sysfs iov directory is used to manage and examine the port P_Key
and guid paravirtualization.
Under iov/ports, the administrator may examine the gid and P_Key tables
as they are present in the device (and as are seen in the "network
view" presented to the SM).
Under the iov/<pci slot number> directories, the admin may map the
index numbers in the physical tables (as under iov/ports) to the
paravirtualized index numbers that guests see.
For example, if the administrator, for port 1 on guest 2 maps physical
pkey index 10 to virtual index 1, then that guest, whenever it uses
its pkey index 1, will actually be using the real pkey index 10.
Based on patch from Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>
For IB ports, we paravirtualize the GUID at index 0 on slaves. The
GUID at index 0 seen by a slave is the actual GUID occupying the GUID
table at the slave-id index.
The driver, by default, requests at startup time that subnet manager
populate its entire guid table with GUIDs. These guids are then mapped
(paravirtualized) to the slaves, and appear for each slave as its GUID
at index 0.
Until each slave has such a guid, its port status is DOWN.
The guid table is cached to support special QP paravirtualization, and
event propagation to slaves on guid change (we test to see if the guid
really changed before propagating an event to the slave).
To support this caching, add capability to __mlx4_ib_query_gid() to
obtain the network view (i.e., physical view) gid at index X, not just
the host (paravirtualized) view.
Based on a patch from Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>
