Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] kprobes: Fix the return address of multiple kretprobes
  [S390] kprobes: disable interrupts throughout
  [S390] ftrace: build without frame pointers on s390
  [S390] mm: add devmem_is_allowed() for STRICT_DEVMEM checking
  [S390] vmlogrdr: purge after recording is switched off
  [S390] cio: fix incorrect ccw_device_init_count
  [S390] tape: add medium state notifications
  [S390] fix get_user_pages_fast

3 files changed, 93 insertions, 22 deletions

diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c
index 6c408670e08..b3a3e8e8656 100644
--- 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);
 }
 
diff --git a/drivers/s390/char/vmlogrdr.c b/drivers/s390/char/vmlogrdr.c
index 9f661426e4a..1cc726b98ec 100644
--- a/drivers/s390/char/vmlogrdr.c
+++ b/drivers/s390/char/vmlogrdr.c
@@ -249,27 +249,25 @@ static int vmlogrdr_recording(struct vmlogrdr_priv_t * logptr,
 	char cp_command[80];
 	char cp_response[160];
 	char *onoff, *qid_string;
+	int rc;
 
-	memset(cp_command, 0x00, sizeof(cp_command));
-	memset(cp_response, 0x00, sizeof(cp_response));
-
-        onoff = ((action == 1) ? "ON" : "OFF");
+	onoff = ((action == 1) ? "ON" : "OFF");
 	qid_string = ((recording_class_AB == 1) ? " QID * " : "");
 
-        /*
+	/*
 	 * The recording commands needs to be called with option QID
 	 * for guests that have previlege classes A or B.
 	 * Purging has to be done as separate step, because recording
 	 * can't be switched on as long as records are on the queue.
 	 * Doing both at the same time doesn't work.
 	 */
-
-	if (purge) {
+	if (purge && (action == 1)) {
+		memset(cp_command, 0x00, sizeof(cp_command));
+		memset(cp_response, 0x00, sizeof(cp_response));
 		snprintf(cp_command, sizeof(cp_command),
 			 "RECORDING %s PURGE %s",
 			 logptr->recording_name,
 			 qid_string);
-
 		cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
 	}
 
@@ -279,19 +277,33 @@ static int vmlogrdr_recording(struct vmlogrdr_priv_t * logptr,
 		logptr->recording_name,
 		onoff,
 		qid_string);
-
 	cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
 	/* The recording command will usually answer with 'Command complete'
 	 * on success, but when the specific service was never connected
 	 * before then there might be an additional informational message
 	 * 'HCPCRC8072I Recording entry not found' before the
-         * 'Command complete'. So I use strstr rather then the strncmp.
+	 * 'Command complete'. So I use strstr rather then the strncmp.
 	 */
 	if (strstr(cp_response,"Command complete"))
-		return 0;
+		rc = 0;
 	else
-		return -EIO;
+		rc = -EIO;
+	/*
+	 * If we turn recording off, we have to purge any remaining records
+	 * afterwards, as a large number of queued records may impact z/VM
+	 * performance.
+	 */
+	if (purge && (action == 0)) {
+		memset(cp_command, 0x00, sizeof(cp_command));
+		memset(cp_response, 0x00, sizeof(cp_response));
+		snprintf(cp_command, sizeof(cp_command),
+			 "RECORDING %s PURGE %s",
+			 logptr->recording_name,
+			 qid_string);
+		cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+	}
 
+	return rc;
 }
 
 
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 2ff8a22d425..e8391b89eff 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1455,7 +1455,16 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
 		break;
 	case IO_SCH_UNREG_ATTACH:
 	case IO_SCH_UNREG:
-		if (cdev)
+		if (!cdev)
+			break;
+		if (cdev->private->state == DEV_STATE_SENSE_ID) {
+			/*
+			 * Note: delayed work triggered by this event
+			 * and repeated calls to sch_event are synchronized
+			 * by the above check for work_pending(cdev).
+			 */
+			dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
+		} else
 			ccw_device_set_notoper(cdev);
 		break;
 	case IO_SCH_NOP: