[S390] tape: add medium state notifications

Add uevent notifications for tape cartridge load and tape
cartridge unload events.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c
index 6c408670e08d72336ecfe1e3298a6db285740787..b3a3e8e8656e6db1be5e3a50b63056c43f0897f6 100644 (file)
--- a/drivers/s390/char/tape_core.c
+++ b/drivers/s390/char/tape_core.c
@@ -209,29 +209,79 @@ tape_state_set(struct tape_device *device, enum tape_state newstate)
        wake_up(&device->state_change_wq);
 }
 
+struct tape_med_state_work_data {
+       struct tape_device *device;
+       enum tape_medium_state state;
+       struct work_struct  work;
+};
+
+static void
+tape_med_state_work_handler(struct work_struct *work)
+{
+       static char env_state_loaded[] = "MEDIUM_STATE=LOADED";
+       static char env_state_unloaded[] = "MEDIUM_STATE=UNLOADED";
+       struct tape_med_state_work_data *p =
+               container_of(work, struct tape_med_state_work_data, work);
+       struct tape_device *device = p->device;
+       char *envp[] = { NULL, NULL };
+
+       switch (p->state) {
+       case MS_UNLOADED:
+               pr_info("%s: The tape cartridge has been successfully "
+                       "unloaded\n", dev_name(&device->cdev->dev));
+               envp[0] = env_state_unloaded;
+               kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp);
+               break;
+       case MS_LOADED:
+               pr_info("%s: A tape cartridge has been mounted\n",
+                       dev_name(&device->cdev->dev));
+               envp[0] = env_state_loaded;
+               kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp);
+               break;
+       default:
+               break;
+       }
+       tape_put_device(device);
+       kfree(p);
+}
+
+static void
+tape_med_state_work(struct tape_device *device, enum tape_medium_state state)
+{
+       struct tape_med_state_work_data *p;
+
+       p = kzalloc(sizeof(*p), GFP_ATOMIC);
+       if (p) {
+               INIT_WORK(&p->work, tape_med_state_work_handler);
+               p->device = tape_get_device(device);
+               p->state = state;
+               schedule_work(&p->work);
+       }
+}
+
 void
 tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate)
 {
-       if (device->medium_state == newstate)
+       enum tape_medium_state oldstate;
+
+       oldstate = device->medium_state;
+       if (oldstate == newstate)
                return;
+       device->medium_state = newstate;
        switch(newstate){
        case MS_UNLOADED:
                device->tape_generic_status |= GMT_DR_OPEN(~0);
-               if (device->medium_state == MS_LOADED)
-                       pr_info("%s: The tape cartridge has been successfully "
-                               "unloaded\n", dev_name(&device->cdev->dev));
+               if (oldstate == MS_LOADED)
+                       tape_med_state_work(device, MS_UNLOADED);
                break;
        case MS_LOADED:
                device->tape_generic_status &= ~GMT_DR_OPEN(~0);
-               if (device->medium_state == MS_UNLOADED)
-                       pr_info("%s: A tape cartridge has been mounted\n",
-                               dev_name(&device->cdev->dev));
+               if (oldstate == MS_UNLOADED)
+                       tape_med_state_work(device, MS_LOADED);
                break;
        default:
-               // print nothing
                break;
        }
-       device->medium_state = newstate;
        wake_up(&device->state_change_wq);
 }