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 6c408670e08d..b3a3e8e8656e 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 9f661426e4a1..1cc726b98ec8 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 2ff8a22d4257..e8391b89eff4 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: