[PATCH] libata: Add support for SATA attachment to SAS adapters

The following patch enhances 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.

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
	target_alloc
		ata_sas_port_alloc
	slave_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
	port_disable
target_destroy
	ata_sas_port_destroy

Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index be15ef5d8d85..cf5eb1da3e32 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -691,6 +691,15 @@ extern int ata_scsi_detect(struct scsi_host_template *sht);
 extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
 extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
 extern int ata_scsi_release(struct Scsi_Host *host);
+extern void ata_sas_port_destroy(struct ata_port *);
+extern struct ata_port *ata_sas_port_alloc(struct ata_host_set *,
+                                           struct ata_port_info *, struct Scsi_Host *);
+extern int ata_sas_port_init(struct ata_port *);
+extern int ata_sas_port_start(struct ata_port *ap);
+extern void ata_sas_port_stop(struct ata_port *ap);
+extern int ata_sas_slave_configure(struct scsi_device *, struct ata_port *);
+extern int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
+                            struct ata_port *ap);
 extern unsigned int ata_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc);
 extern int sata_scr_valid(struct ata_port *ap);
 extern int sata_scr_read(struct ata_port *ap, int reg, u32 *val);