[S390] cio: make steal lock procedure more robust

An Unconditional Reserve + Release operation (steal lock) for a
boxed device may fail when encountering special error cases
(e.g. unit checks or path errors). Fix this by using the more
robust ccw_request infrastructure for performing the steal lock
CCW program.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 26 insertions, 29 deletions

diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 8d565ff85e43..7d42417bc2c7 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -641,6 +641,23 @@ ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 }
 
 /*
+ * Handle path verification event in boxed state.
+ */
+static void ccw_device_boxed_verify(struct ccw_device *cdev,
+                                    enum dev_event dev_event)
+{
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+        if (cdev->online) {
+                if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
+                        ccw_device_done(cdev, DEV_STATE_NOT_OPER);
+                else
+                        ccw_device_online_verify(cdev, dev_event);
+        } else
+                css_schedule_eval(sch->schid);
+}
+
+/*
  * Got an interrupt for a normal io (state online).
  */
 static void
@@ -817,32 +834,6 @@ ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 }
 
 static void
-ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event)
-{
-        struct irb *irb;
-
-        switch (dev_event) {
-        case DEV_EVENT_INTERRUPT:
-                irb = (struct irb *) __LC_IRB;
-                /* Check for unsolicited interrupt. */
-                if ((scsw_stctl(&irb->scsw) ==
-                     (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
-                    (!scsw_cc(&irb->scsw)))
-                        /* FIXME: we should restart stlck here, but this
-                         * is extremely unlikely ... */
-                        goto out_wakeup;
-
-                ccw_device_accumulate_irb(cdev, irb);
-                /* We don't care about basic sense etc. */
-                break;
-        default: /* timeout */
-                break;
-        }
-out_wakeup:
-        wake_up(&cdev->private->wait_q);
-}
-
-static void
 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 {
         struct subchannel *sch;
@@ -1010,9 +1001,9 @@ fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
         },
         [DEV_STATE_BOXED] = {
                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
-                [DEV_EVENT_INTERRUPT]   = ccw_device_stlck_done,
-                [DEV_EVENT_TIMEOUT]     = ccw_device_stlck_done,
-                [DEV_EVENT_VERIFY]      = ccw_device_nop,
+                [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
+                [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
+                [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
         },
         /* states to wait for i/o completion before doing something */
         [DEV_STATE_TIMEOUT_KILL] = {
@@ -1052,6 +1043,12 @@ fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
         },
+        [DEV_STATE_STEAL_LOCK] = {
+                [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
+                [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
+                [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
+                [DEV_EVENT_VERIFY]      = ccw_device_nop,
+        },
 };
 
 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);