[S390] rework of channel measurement facility.

Fixes for several channel measurement facility bugs:
* Blocks copied from the hardware might not be consistent. Solve this
  by moving the copying into idle state and repeating the copying.
* avg_sample_interval changed with every read, even though no new block
  was available. Solve this by storing a timestamp when the last new
  block was received.
* Several locking issues.
* Measurements were not reenabled after a disconnected device became
  available again.
* Remove #defines for ioctls that were never implemented.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 17 insertions, 1 deletions

diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 5ec8ef1df9f..7d0dd72635e 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -336,8 +336,11 @@ ccw_device_oper_notify(void *data)
         if (!ret)
                 /* Driver doesn't want device back. */
                 ccw_device_do_unreg_rereg((void *)cdev);
-        else
+        else {
+                /* Reenable channel measurements, if needed. */
+                cmf_reenable(cdev);
                 wake_up(&cdev->private->wait_q);
+        }
 }
 
 /*
@@ -1095,6 +1098,13 @@ ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
         dev_fsm_event(cdev, dev_event);
 }
 
+static void ccw_device_update_cmfblock(struct ccw_device *cdev,
+                                       enum dev_event dev_event)
+{
+        cmf_retry_copy_block(cdev);
+        cdev->private->state = DEV_STATE_ONLINE;
+        dev_fsm_event(cdev, dev_event);
+}
 
 static void
 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
@@ -1249,6 +1259,12 @@ fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
         },
+        [DEV_STATE_CMFUPDATE] = {
+                [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
+                [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
+                [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
+                [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
+        },
 };
 
 /*