[PATCH 0/2] libata: support SATA devices on SAS HBAs

[Brian King <brking@us.ibm.com>]

The following patches enhance libata to allow SAS device drivers
to utilize libata to talk to SATA devices. It introduces some
new APIs which allow libata to be used without allocating a
virtual scsi host. In the context of SAS, a struct ata_port
is not a physical port, but rather becomes a virtual construct.

Since my last post, I have removed the dependence on the host_set
struct. The following two patches depend on the qc_transport patch:

http://marc.theaimsgroup.com/?l=linux-ide&m=112845939215286&w=2

The API is the same as the last time I posted it to linux-ide,
but here is the description again:

New APIs:

ata_sas_port_alloc - Allocate an ata_port 
ata_sas_port_init - Initialize an ata_port (probe device, etc)
ata_sas_port_destroy - Free an ata_port allocated by ata_sas_port_alloc
ata_sas_slave_configure - configure scsi device
ata_sas_queuecmd - queue a scsi command, similar to ata_scsi_queuecomand

These new APIs can be used either directly by a SAS LLDD or could be used
by the SAS transport class. 

Possible usage for a SAS LLDD would be:

scsi_scan_host
	slave_alloc
		ata_sas_port_alloc
		ata_sas_port_init
	slave_configure
		ata_sas_slave_configure

Commands received by the LLDD for SATA devices would call ata_sas_queuecmd.

Device teardown would occur with:

slave_destroy
	ata_sas_port_destroy



-- 
Brian King
eServer Storage I/O
IBM Linux Technology Center