[SCSI] libata, libsas: introduce sched_eh and end_eh port ops
When managing shost->host_eh_scheduled libata assumes that there is a
1:1 shost-to-ata_port relationship. libsas creates a 1:N relationship
so it needs to manage host_eh_scheduled cumulatively at the host level.
The sched_eh and end_eh port port ops allow libsas to track when domain
devices enter/leave the "eh-pending" state under ha->lock (previously
named ha->state_lock, but it is no longer just a lock for ha->state
changes).
Since host_eh_scheduled indicates eh without backing commands pinning
the device it can be deallocated at any time. Move the taking of the
domain_device reference under the port_lock to guarantee that the
ata_port stays around for the duration of eh.
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index 10ce74f..814d8cb 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -179,6 +179,7 @@
enum {
SAS_DEV_GONE,
SAS_DEV_DESTROY,
+ SAS_DEV_EH_PENDING,
};
struct domain_device {
@@ -386,7 +387,8 @@
struct list_head defer_q; /* work queued while draining */
struct mutex drain_mutex;
unsigned long state;
- spinlock_t state_lock;
+ spinlock_t lock;
+ int eh_active;
struct mutex disco_mutex;