[SCSI] scsi_dh: Change the scsidh_activate interface to be asynchronous

Make scsi_dh_activate() function asynchronous, by taking in two additional
parameters, one is the callback function and the other is the data to call
the callback function with.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

2 files changed, 6 insertions, 3 deletions

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 92c4c3bd916d..68d185c79bae 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -177,6 +177,7 @@ struct scsi_dh_devlist {
         char *model;
 };
 
+typedef void (*activate_complete)(void *, int);
 struct scsi_device_handler {
         /* Used by the infrastructure */
         struct list_head list; /* list of scsi_device_handlers */
@@ -188,7 +189,7 @@ struct scsi_device_handler {
         int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
         int (*attach)(struct scsi_device *);
         void (*detach)(struct scsi_device *);
-        int (*activate)(struct scsi_device *);
+        int (*activate)(struct scsi_device *, activate_complete, void *);
         int (*prep_fn)(struct scsi_device *, struct request *);
         int (*set_params)(struct scsi_device *, const char *);
 };
diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h
index ff2407405b42..e3f2db212ddc 100644
--- a/include/scsi/scsi_dh.h
+++ b/include/scsi/scsi_dh.h
@@ -56,14 +56,16 @@ enum {
         SCSI_DH_DRIVER_MAX,
 };
 #if defined(CONFIG_SCSI_DH) || defined(CONFIG_SCSI_DH_MODULE)
-extern int scsi_dh_activate(struct request_queue *);
+extern int scsi_dh_activate(struct request_queue *, activate_complete, void *);
 extern int scsi_dh_handler_exist(const char *);
 extern int scsi_dh_attach(struct request_queue *, const char *);
 extern void scsi_dh_detach(struct request_queue *);
 extern int scsi_dh_set_params(struct request_queue *, const char *);
 #else
-static inline int scsi_dh_activate(struct request_queue *req)
+static inline int scsi_dh_activate(struct request_queue *req,
+                                        activate_complete fn, void *data)
 {
+        fn(data, 0);
         return 0;
 }
 static inline int scsi_dh_handler_exist(const char *name)