[SCSI] libsas: execute transport link resets with libata-eh via host workqueue

Link resets leave ata affiliations intact, so arrange for libsas to make
an effort to avoid dropping the device due to a slow-to-recover link.
Towards this end carry out reset in the host workqueue so that it can
check for ata devices and kick the reset request to libata.  Hard
resets, in contrast, bypass libata since they are meant for associating
an ata device with another initiator in the domain (tears down
affiliations).

Need to add a new transport_sas_phy_reset() since the current
sas_phy_reset() is a utility function to libsas lldds.  They are not
prepared for it to loop back into eh.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 1 insertions, 1 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index a9b282038000..c61316e9d2f7 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -863,6 +863,7 @@ void ata_port_wait_eh(struct ata_port *ap)
                 goto retry;
         }
 }
+EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 
 static int ata_eh_nr_in_flight(struct ata_port *ap)
 {
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 814486d35c44..1fab235ee516 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -151,7 +151,6 @@ extern void ata_eh_acquire(struct ata_port *ap);
 extern void ata_eh_release(struct ata_port *ap);
 extern enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd);
 extern void ata_scsi_error(struct Scsi_Host *host);
-extern void ata_port_wait_eh(struct ata_port *ap);
 extern void ata_eh_fastdrain_timerfn(unsigned long arg);
 extern void ata_qc_schedule_eh(struct ata_queued_cmd *qc);
 extern void ata_dev_disable(struct ata_device *dev);