1 files changed, 17 insertions, 12 deletions

diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c
index 3ee1cbc89479..6fae3d285ae7 100644
--- a/drivers/scsi/device_handler/scsi_dh.c
+++ b/drivers/scsi/device_handler/scsi_dh.c
@@ -21,6 +21,7 @@
  *               Mike Anderson <andmike@linux.vnet.ibm.com>
  */
 
+#include <linux/slab.h>
 #include <scsi/scsi_dh.h>
 #include "../scsi_priv.h"
 
@@ -226,7 +227,7 @@ store_dh_state(struct device *dev, struct device_attribute *attr,
                          * Activate a device handler
                          */
                         if (scsi_dh->activate)
-                                err = scsi_dh->activate(sdev);
+                                err = scsi_dh->activate(sdev, NULL, NULL);
                         else
                                 err = 0;
                 }
@@ -304,18 +305,15 @@ static int scsi_dh_notifier(struct notifier_block *nb,
         sdev = to_scsi_device(dev);
 
         if (action == BUS_NOTIFY_ADD_DEVICE) {
+                err = device_create_file(dev, &scsi_dh_state_attr);
+                /* don't care about err */
                 devinfo = device_handler_match(NULL, sdev);
-                if (!devinfo)
-                        goto out;
-
-                err = scsi_dh_handler_attach(sdev, devinfo);
-                if (!err)
-                        err = device_create_file(dev, &scsi_dh_state_attr);
+                if (devinfo)
+                        err = scsi_dh_handler_attach(sdev, devinfo);
         } else if (action == BUS_NOTIFY_DEL_DEVICE) {
                 device_remove_file(dev, &scsi_dh_state_attr);
                 scsi_dh_handler_detach(sdev, NULL);
         }
-out:
         return err;
 }
 
@@ -423,10 +421,17 @@ EXPORT_SYMBOL_GPL(scsi_unregister_device_handler);
 /*
  * scsi_dh_activate - activate the path associated with the scsi_device
  *      corresponding to the given request queue.
- * @q - Request queue that is associated with the scsi_device to be
- *      activated.
+ *     Returns immediately without waiting for activation to be completed.
+ * @q    - Request queue that is associated with the scsi_device to be
+ *         activated.
+ * @fn   - Function to be called upon completion of the activation.
+ *         Function fn is called with data (below) and the error code.
+ *         Function fn may be called from the same calling context. So,
+ *         do not hold the lock in the caller which may be needed in fn.
+ * @data - data passed to the function fn upon completion.
+ *
  */
-int scsi_dh_activate(struct request_queue *q)
+int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data)
 {
         int err = 0;
         unsigned long flags;
@@ -445,7 +450,7 @@ int scsi_dh_activate(struct request_queue *q)
                 return err;
 
         if (scsi_dh->activate)
-                err = scsi_dh->activate(sdev);
+                err = scsi_dh->activate(sdev, fn, data);
         put_device(&sdev->sdev_gendev);
         return err;
 }