[S390] cio: Remove grace period for vary off chpid.

The grace period handling introduced needless complexity. It didn't
help the dasd driver (which can handle terminated I/O just well),
and it doesn't help for long running channel programs (which won't
complete during the grace period anyway). Terminating I/O using a
path that just disappeared immediately is much more consistent with
what the user expects.

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

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 07c7f19339d2228db33f77e6a2adfe89015433e0..eabe018d348fa67ca430ba905a4f81af92cf5ea5 100644 (file)
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -707,8 +707,7 @@ chp_process_crw(int chpid, int on)
        return chp_add(chpid);
 }
 
-static inline int
-__check_for_io_and_kill(struct subchannel *sch, int index)
+static inline int check_for_io_on_path(struct subchannel *sch, int index)
 {
        int cc;
 
@@ -718,10 +717,8 @@ __check_for_io_and_kill(struct subchannel *sch, int index)
        cc = stsch(sch->schid, &sch->schib);
        if (cc)
                return 0;
-       if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
-               device_set_waiting(sch);
+       if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index))
                return 1;
-       }
        return 0;
 }
 
@@ -750,12 +747,10 @@ __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
                } else {
                        sch->opm &= ~(0x80 >> chp);
                        sch->lpm &= ~(0x80 >> chp);
-                       /*
-                        * Give running I/O a grace period in which it
-                        * can successfully terminate, even using the
-                        * just varied off path. Then kill it.
-                        */
-                       if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
+                       if (check_for_io_on_path(sch, chp))
+                               /* Path verification is done after killing. */
+                               device_kill_io(sch);
+                       else if (!sch->lpm) {
                                if (css_enqueue_subchannel_slow(sch->schid)) {
                                        css_clear_subchannel_slow_list();
                                        need_rescan = 1;

diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
index 15bd1e28ed70d74d1095ef86345414dafa6f886d..4c2ff83362887aafe64fea2a5ebf6137b8456b9a 100644 (file)
--- a/drivers/s390/cio/css.h
+++ b/drivers/s390/cio/css.h
@@ -170,7 +170,7 @@ void device_trigger_reprobe(struct subchannel *);
 
 /* Helper functions for vary on/off. */
 int device_is_online(struct subchannel *);
-void device_set_waiting(struct subchannel *);
+void device_kill_io(struct subchannel *);
 
 /* Machine check helper function. */
 void device_kill_pending_timer(struct subchannel *);

diff --git a/drivers/s390/cio/device.h b/drivers/s390/cio/device.h
index 00be9a5b4acde18141a76d7aef38ad4b90b2347c..c6140cc97a80933bc129ca3b091183fdcd3ec747 100644 (file)
--- a/drivers/s390/cio/device.h
+++ b/drivers/s390/cio/device.h
@@ -21,7 +21,6 @@ enum dev_state {
        /* states to wait for i/o completion before doing something */
        DEV_STATE_CLEAR_VERIFY,
        DEV_STATE_TIMEOUT_KILL,
-       DEV_STATE_WAIT4IO,
        DEV_STATE_QUIESCE,
        /* special states for devices gone not operational */
        DEV_STATE_DISCONNECTED,

diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 392eb33f3a9ce664a519a8c01cf55e232f5dfcc8..44e4a53c5981f0cc3307eff035b8c32a96ae4e08 100644 (file)
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -59,18 +59,6 @@ device_set_disconnected(struct subchannel *sch)
        cdev->private->state = DEV_STATE_DISCONNECTED;
 }
 
-void
-device_set_waiting(struct subchannel *sch)
-{
-       struct ccw_device *cdev;
-
-       if (!sch->dev.driver_data)
-               return;
-       cdev = sch->dev.driver_data;
-       ccw_device_set_timeout(cdev, 10*HZ);
-       cdev->private->state = DEV_STATE_WAIT4IO;
-}
-
 /*
  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  */
@@ -947,7 +935,7 @@ ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
        cdev->private->state = DEV_STATE_ONLINE;
        if (cdev->handler)
                cdev->handler(cdev, cdev->private->intparm,
-                             ERR_PTR(-ETIMEDOUT));
+                             ERR_PTR(-EIO));
        if (!sch->lpm) {
                PREPARE_WORK(&cdev->private->kick_work,
                             ccw_device_nopath_notify, (void *)cdev);
@@ -984,51 +972,15 @@ ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
        cdev->private->state = DEV_STATE_ONLINE;
        if (cdev->handler)
                cdev->handler(cdev, cdev->private->intparm,
-                             ERR_PTR(-ETIMEDOUT));
+                             ERR_PTR(-EIO));
 }
 
-static void
-ccw_device_wait4io_irq(struct ccw_device *cdev, enum dev_event dev_event)
-{
-       struct irb *irb;
-       struct subchannel *sch;
-
-       irb = (struct irb *) __LC_IRB;
-       /*
-        * Accumulate status and find out if a basic sense is needed.
-        * This is fine since we have already adapted the lpm.
-        */
-       ccw_device_accumulate_irb(cdev, irb);
-       if (cdev->private->flags.dosense) {
-               if (ccw_device_do_sense(cdev, irb) == 0) {
-                       cdev->private->state = DEV_STATE_W4SENSE;
-               }
-               return;
-       }
-
-       /* Iff device is idle, reset timeout. */
-       sch = to_subchannel(cdev->dev.parent);
-       if (!stsch(sch->schid, &sch->schib))
-               if (sch->schib.scsw.actl == 0)
-                       ccw_device_set_timeout(cdev, 0);
-       /* Call the handler. */
-       ccw_device_call_handler(cdev);
-       if (!sch->lpm) {
-               PREPARE_WORK(&cdev->private->kick_work,
-                            ccw_device_nopath_notify, (void *)cdev);
-               queue_work(ccw_device_notify_work, &cdev->private->kick_work);
-       } else if (cdev->private->flags.doverify)
-               ccw_device_online_verify(cdev, 0);
-}
-
-static void
-ccw_device_wait4io_timeout(struct ccw_device *cdev, enum dev_event dev_event)
+void device_kill_io(struct subchannel *sch)
 {
        int ret;
-       struct subchannel *sch;
+       struct ccw_device *cdev;
 
-       sch = to_subchannel(cdev->dev.parent);
-       ccw_device_set_timeout(cdev, 0);
+       cdev = sch->dev.driver_data;
        ret = ccw_device_cancel_halt_clear(cdev);
        if (ret == -EBUSY) {
                ccw_device_set_timeout(cdev, 3*HZ);
@@ -1047,12 +999,12 @@ ccw_device_wait4io_timeout(struct ccw_device *cdev, enum dev_event dev_event)
        }
        if (cdev->handler)
                cdev->handler(cdev, cdev->private->intparm,
-                             ERR_PTR(-ETIMEDOUT));
+                             ERR_PTR(-EIO));
        if (!sch->lpm) {
                PREPARE_WORK(&cdev->private->kick_work,
                             ccw_device_nopath_notify, (void *)cdev);
                queue_work(ccw_device_notify_work, &cdev->private->kick_work);
-       } else if (cdev->private->flags.doverify)
+       } else
                /* Start delayed path verification. */
                ccw_device_online_verify(cdev, 0);
 }
@@ -1289,12 +1241,6 @@ fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
                [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
                [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
        },
-       [DEV_STATE_WAIT4IO] = {
-               [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
-               [DEV_EVENT_INTERRUPT]   = ccw_device_wait4io_irq,
-               [DEV_EVENT_TIMEOUT]     = ccw_device_wait4io_timeout,
-               [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
-       },
        [DEV_STATE_QUIESCE] = {
                [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
                [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,

diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index 96219935a06ac33efdcfd40a3f44878ca48f46e9..b39c1fa48acd22cac1fd92990da9699193913510 100644 (file)
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -50,7 +50,6 @@ ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
        if (cdev->private->state == DEV_STATE_NOT_OPER)
                return -ENODEV;
        if (cdev->private->state != DEV_STATE_ONLINE &&
-           cdev->private->state != DEV_STATE_WAIT4IO &&
            cdev->private->state != DEV_STATE_W4SENSE)
                return -EINVAL;
        sch = to_subchannel(cdev->dev.parent);
@@ -155,7 +154,6 @@ ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
        if (cdev->private->state == DEV_STATE_NOT_OPER)
                return -ENODEV;
        if (cdev->private->state != DEV_STATE_ONLINE &&
-           cdev->private->state != DEV_STATE_WAIT4IO &&
            cdev->private->state != DEV_STATE_W4SENSE)
                return -EINVAL;
        sch = to_subchannel(cdev->dev.parent);