linux

[SCSI] SAS transport class The SAS transport class contains common code to deal with SAS HBAs, an aproximated representation of SAS topologies in the driver model, and various sysfs attributes to expose these topologies and managment interfaces to userspace. In addition to the basic SCSI core objects this transport class introduces two additional intermediate objects: The SAS PHY as represented by struct sas_phy defines an "outgoing" PHY on a SAS HBA or Expander, and the SAS remote PHY represented by struct sas_rphy defines an "incoming" PHY on a SAS Expander or end device. Note that this is purely a software concept, the underlying hardware for a PHY and a remote PHY is the exactly the same. There is no concept of a SAS port in this code, users can see what PHYs form a wide port based on the port_identifier attribute, which is the same for all PHYs in a port. This submission doesn't handle hot-plug addition or removal of SAS devices and thus doesn't do scanning in a workqueue yet, that will be added in phase2 after this submission. In a third phase I will add additional managment infrastructure. I think this submission is ready for 2.6.14, but additional comments are of course very welcome. I'd like to thanks James Smart a lot for his very useful input on the design. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com> 2005-09-09 16:22:50 +02:00