12 files changed, 253 insertions, 64 deletions

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index c7319a07ba35..f26a2ee3aad8 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -319,7 +319,7 @@ ccwgroup_online_store (struct device *dev, struct device_attribute *attr, const
         if (!try_module_get(gdrv->owner))
                 return -EINVAL;
 
-        value = simple_strtoul(buf, 0, 0);
+        value = simple_strtoul(buf, NULL, 0);
         ret = count;
         if (value == 1)
                 ccwgroup_set_online(gdev);
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index a01f3bba4a7b..61ce3f1d5228 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -1464,6 +1464,40 @@ chsc_get_chp_desc(struct subchannel *sch, int chp_no)
         return desc;
 }
 
+static int reset_channel_path(struct channel_path *chp)
+{
+        int cc;
+
+        cc = rchp(chp->id);
+        switch (cc) {
+        case 0:
+                return 0;
+        case 2:
+                return -EBUSY;
+        default:
+                return -ENODEV;
+        }
+}
+
+static void reset_channel_paths_css(struct channel_subsystem *css)
+{
+        int i;
+
+        for (i = 0; i <= __MAX_CHPID; i++) {
+                if (css->chps[i])
+                        reset_channel_path(css->chps[i]);
+        }
+}
+
+void cio_reset_channel_paths(void)
+{
+        int i;
+
+        for (i = 0; i <= __MAX_CSSID; i++) {
+                if (css[i] && css[i]->valid)
+                        reset_channel_paths_css(css[i]);
+        }
+}
 
 static int __init
 chsc_alloc_sei_area(void)
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 6fec90eab00e..89320c1ad825 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -519,6 +519,7 @@ cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
         memset(sch, 0, sizeof(struct subchannel));
 
         spin_lock_init(&sch->lock);
+        mutex_init(&sch->reg_mutex);
 
         /* Set a name for the subchannel */
         snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x", schid.ssid,
@@ -797,7 +798,7 @@ struct subchannel *
 cio_get_console_subchannel(void)
 {
         if (!console_subchannel_in_use)
-                return 0;
+                return NULL;
         return &console_subchannel;
 }
 
@@ -875,5 +876,6 @@ void
 reipl(unsigned long devno)
 {
         clear_all_subchannels();
+        cio_reset_channel_paths();
         do_reipl(devno);
 }
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index 0ca987344e07..4541c1af4b66 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -2,6 +2,7 @@
 #define S390_CIO_H
 
 #include "schid.h"
+#include <linux/mutex.h>
 
 /*
  * where we put the ssd info
@@ -87,7 +88,7 @@ struct orb {
 struct subchannel {
         struct subchannel_id schid;
         spinlock_t lock;        /* subchannel lock */
-
+        struct mutex reg_mutex;
         enum {
                 SUBCHANNEL_TYPE_IO = 0,
                 SUBCHANNEL_TYPE_CHSC = 1,
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index 1c3e8e9012b0..0df3af1f08de 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -1140,7 +1140,7 @@ static struct attribute *cmf_attributes[] = {
         &dev_attr_avg_device_disconnect_time.attr,
         &dev_attr_avg_control_unit_queuing_time.attr,
         &dev_attr_avg_device_active_only_time.attr,
-        0,
+        NULL,
 };
 
 static struct attribute_group cmf_attr_group = {
@@ -1160,7 +1160,7 @@ static struct attribute *cmf_attributes_ext[] = {
         &dev_attr_avg_device_active_only_time.attr,
         &dev_attr_avg_device_busy_time.attr,
         &dev_attr_avg_initial_command_response_time.attr,
-        0,
+        NULL,
 };
 
 static struct attribute_group cmf_attr_group_ext = {
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 1d3be80797f8..13eeea3d547f 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -108,6 +108,24 @@ css_subchannel_release(struct device *dev)
 
 extern int css_get_ssd_info(struct subchannel *sch);
 
+
+int css_sch_device_register(struct subchannel *sch)
+{
+        int ret;
+
+        mutex_lock(&sch->reg_mutex);
+        ret = device_register(&sch->dev);
+        mutex_unlock(&sch->reg_mutex);
+        return ret;
+}
+
+void css_sch_device_unregister(struct subchannel *sch)
+{
+        mutex_lock(&sch->reg_mutex);
+        device_unregister(&sch->dev);
+        mutex_unlock(&sch->reg_mutex);
+}
+
 static int
 css_register_subchannel(struct subchannel *sch)
 {
@@ -119,7 +137,7 @@ css_register_subchannel(struct subchannel *sch)
         sch->dev.release = &css_subchannel_release;
         
         /* make it known to the system */
-        ret = device_register(&sch->dev);
+        ret = css_sch_device_register(sch);
         if (ret)
                 printk (KERN_WARNING "%s: could not register %s\n",
                         __func__, sch->dev.bus_id);
@@ -250,7 +268,7 @@ css_evaluate_subchannel(struct subchannel_id schid, int slow)
                  * The device will be killed automatically.
                  */
                 cio_disable_subchannel(sch);
-                device_unregister(&sch->dev);
+                css_sch_device_unregister(sch);
                 /* Reset intparm to zeroes. */
                 sch->schib.pmcw.intparm = 0;
                 cio_modify(sch);
@@ -264,7 +282,7 @@ css_evaluate_subchannel(struct subchannel_id schid, int slow)
                  * away in any case.
                  */
                 if (!disc) {
-                        device_unregister(&sch->dev);
+                        css_sch_device_unregister(sch);
                         /* Reset intparm to zeroes. */
                         sch->schib.pmcw.intparm = 0;
                         cio_modify(sch);
@@ -605,9 +623,13 @@ init_channel_subsystem (void)
                 ret = device_register(&css[i]->device);
                 if (ret)
                         goto out_free;
-                if (css_characteristics_avail && css_chsc_characteristics.secm)
-                        device_create_file(&css[i]->device,
-                                           &dev_attr_cm_enable);
+                if (css_characteristics_avail &&
+                    css_chsc_characteristics.secm) {
+                        ret = device_create_file(&css[i]->device,
+                                                 &dev_attr_cm_enable);
+                        if (ret)
+                                goto out_device;
+                }
         }
         css_init_done = 1;
 
@@ -615,6 +637,8 @@ init_channel_subsystem (void)
 
         for_each_subchannel(__init_channel_subsystem, NULL);
         return 0;
+out_device:
+        device_unregister(&css[i]->device);
 out_free:
         kfree(css[i]);
 out_unregister:
diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
index e210f89a2449..8aabb4adeb5f 100644
--- a/drivers/s390/cio/css.h
+++ b/drivers/s390/cio/css.h
@@ -100,7 +100,7 @@ struct ccw_device_private {
         struct qdio_irq *qdio_data;
         struct irb irb;         /* device status */
         struct senseid senseid; /* SenseID info */
-        struct pgid pgid;       /* path group ID */
+        struct pgid pgid[8];    /* path group IDs per chpid*/
         struct ccw1 iccws[2];   /* ccws for SNID/SID/SPGID commands */
         struct work_struct kick_work;
         wait_queue_head_t wait_q;
@@ -136,6 +136,8 @@ extern struct bus_type css_bus_type;
 extern struct css_driver io_subchannel_driver;
 
 extern int css_probe_device(struct subchannel_id);
+extern int css_sch_device_register(struct subchannel *);
+extern void css_sch_device_unregister(struct subchannel *);
 extern struct subchannel * get_subchannel_by_schid(struct subchannel_id);
 extern int css_init_done;
 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 67f0de6aed33..585fa04233c3 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -100,7 +100,7 @@ ccw_uevent (struct device *dev, char **envp, int num_envp,
         if ((buffer_size - length <= 0) || (i >= num_envp))
                 return -ENOMEM;
 
-        envp[i] = 0;
+        envp[i] = NULL;
 
         return 0;
 }
@@ -280,7 +280,7 @@ ccw_device_remove_disconnected(struct ccw_device *cdev)
          * 'throw away device'.
          */
         sch = to_subchannel(cdev->dev.parent);
-        device_unregister(&sch->dev);
+        css_sch_device_unregister(sch);
         /* Reset intparm to zeroes. */
         sch->schib.pmcw.intparm = 0;
         cio_modify(sch);
@@ -625,7 +625,7 @@ ccw_device_do_unreg_rereg(void *data)
                                         other_sch->schib.pmcw.intparm = 0;
                                         cio_modify(other_sch);
                                 }
-                                device_unregister(&other_sch->dev);
+                                css_sch_device_unregister(other_sch);
                         }
                 }
                 /* Update ssd info here. */
@@ -709,7 +709,7 @@ ccw_device_call_sch_unregister(void *data)
         struct subchannel *sch;
 
         sch = to_subchannel(cdev->dev.parent);
-        device_unregister(&sch->dev);
+        css_sch_device_unregister(sch);
         /* Reset intparm to zeroes. */
         sch->schib.pmcw.intparm = 0;
         cio_modify(sch);
@@ -1057,7 +1057,7 @@ get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
                                  __ccwdev_check_busid);
         put_driver(drv);
 
-        return dev ? to_ccwdev(dev) : 0;
+        return dev ? to_ccwdev(dev) : NULL;
 }
 
 /************************** device driver handling ************************/
@@ -1082,7 +1082,7 @@ ccw_device_probe (struct device *dev)
         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
 
         if (ret) {
-                cdev->drv = 0;
+                cdev->drv = NULL;
                 return ret;
         }
 
@@ -1113,7 +1113,7 @@ ccw_device_remove (struct device *dev)
                                  ret, cdev->dev.bus_id);
         }
         ccw_device_set_timeout(cdev, 0);
-        cdev->drv = 0;
+        cdev->drv = NULL;
         return 0;
 }
 
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index cb1af0b6f033..ac6e0c7e43d9 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -378,6 +378,56 @@ ccw_device_done(struct ccw_device *cdev, int state)
                 put_device (&cdev->dev);
 }
 
+static inline int cmp_pgid(struct pgid *p1, struct pgid *p2)
+{
+        char *c1;
+        char *c2;
+
+        c1 = (char *)p1;
+        c2 = (char *)p2;
+
+        return memcmp(c1 + 1, c2 + 1, sizeof(struct pgid) - 1);
+}
+
+static void __ccw_device_get_common_pgid(struct ccw_device *cdev)
+{
+        int i;
+        int last;
+
+        last = 0;
+        for (i = 0; i < 8; i++) {
+                if (cdev->private->pgid[i].inf.ps.state1 == SNID_STATE1_RESET)
+                        /* No PGID yet */
+                        continue;
+                if (cdev->private->pgid[last].inf.ps.state1 ==
+                    SNID_STATE1_RESET) {
+                        /* First non-zero PGID */
+                        last = i;
+                        continue;
+                }
+                if (cmp_pgid(&cdev->private->pgid[i],
+                             &cdev->private->pgid[last]) == 0)
+                        /* Non-conflicting PGIDs */
+                        continue;
+
+                /* PGID mismatch, can't pathgroup. */
+                CIO_MSG_EVENT(0, "SNID - pgid mismatch for device "
+                              "0.%x.%04x, can't pathgroup\n",
+                              cdev->private->ssid, cdev->private->devno);
+                cdev->private->options.pgroup = 0;
+                return;
+        }
+        if (cdev->private->pgid[last].inf.ps.state1 ==
+            SNID_STATE1_RESET)
+                /* No previous pgid found */
+                memcpy(&cdev->private->pgid[0], &css[0]->global_pgid,
+                       sizeof(struct pgid));
+        else
+                /* Use existing pgid */
+                memcpy(&cdev->private->pgid[0], &cdev->private->pgid[last],
+                       sizeof(struct pgid));
+}
+
 /*
  * Function called from device_pgid.c after sense path ground has completed.
  */
@@ -388,24 +438,26 @@ ccw_device_sense_pgid_done(struct ccw_device *cdev, int err)
 
         sch = to_subchannel(cdev->dev.parent);
         switch (err) {
-        case 0:
-                /* Start Path Group verification. */
-                sch->vpm = 0;   /* Start with no path groups set. */
-                cdev->private->state = DEV_STATE_VERIFY;
-                ccw_device_verify_start(cdev);
+        case -EOPNOTSUPP: /* path grouping not supported, use nop instead. */
+                cdev->private->options.pgroup = 0;
+                break;
+        case 0: /* success */
+        case -EACCES: /* partial success, some paths not operational */
+                /* Check if all pgids are equal or 0. */
+                __ccw_device_get_common_pgid(cdev);
                 break;
         case -ETIME:            /* Sense path group id stopped by timeout. */
         case -EUSERS:           /* device is reserved for someone else. */
                 ccw_device_done(cdev, DEV_STATE_BOXED);
-                break;
-        case -EOPNOTSUPP: /* path grouping not supported, just set online. */
-                cdev->private->options.pgroup = 0;
-                ccw_device_done(cdev, DEV_STATE_ONLINE);
-                break;
+                return;
         default:
                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
-                break;
+                return;
         }
+        /* Start Path Group verification. */
+        sch->vpm = 0;   /* Start with no path groups set. */
+        cdev->private->state = DEV_STATE_VERIFY;
+        ccw_device_verify_start(cdev);
 }
 
 /*
@@ -562,8 +614,9 @@ ccw_device_online(struct ccw_device *cdev)
         }
         /* Do we want to do path grouping? */
         if (!cdev->private->options.pgroup) {
-                /* No, set state online immediately. */
-                ccw_device_done(cdev, DEV_STATE_ONLINE);
+                /* Start initial path verification. */
+                cdev->private->state = DEV_STATE_VERIFY;
+                ccw_device_verify_start(cdev);
                 return 0;
         }
         /* Do a SensePGID first. */
@@ -609,6 +662,7 @@ ccw_device_offline(struct ccw_device *cdev)
         /* Are we doing path grouping? */
         if (!cdev->private->options.pgroup) {
                 /* No, set state offline immediately. */
+                sch->vpm = 0;
                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
                 return 0;
         }
@@ -705,8 +759,6 @@ ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 {
         struct subchannel *sch;
 
-        if (!cdev->private->options.pgroup)
-                return;
         if (cdev->private->state == DEV_STATE_W4SENSE) {
                 cdev->private->flags.doverify = 1;
                 return;
@@ -995,8 +1047,7 @@ static void
 ccw_device_wait4io_verify(struct ccw_device *cdev, enum dev_event dev_event)
 {
         /* When the I/O has terminated, we have to start verification. */
-        if (cdev->private->options.pgroup)
-                cdev->private->flags.doverify = 1;
+        cdev->private->flags.doverify = 1;
 }
 
 static void
diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c
index 54cb64ed0786..32610fd8868e 100644
--- a/drivers/s390/cio/device_pgid.c
+++ b/drivers/s390/cio/device_pgid.c
@@ -33,12 +33,17 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
         struct subchannel *sch;
         struct ccw1 *ccw;
         int ret;
+        int i;
 
         sch = to_subchannel(cdev->dev.parent);
+        /* Return if we already checked on all paths. */
+        if (cdev->private->imask == 0)
+                return (sch->lpm == 0) ? -ENODEV : -EACCES;
+        i = 8 - ffs(cdev->private->imask);
+
         /* Setup sense path group id channel program. */
         ccw = cdev->private->iccws;
         ccw->cmd_code = CCW_CMD_SENSE_PGID;
-        ccw->cda = (__u32) __pa (&cdev->private->pgid);
         ccw->count = sizeof (struct pgid);
         ccw->flags = CCW_FLAG_SLI;
 
@@ -48,6 +53,7 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
         ret = -ENODEV;
         while (cdev->private->imask != 0) {
                 /* Try every path multiple times. */
+                ccw->cda = (__u32) __pa (&cdev->private->pgid[i]);
                 if (cdev->private->iretry > 0) {
                         cdev->private->iretry--;
                         ret = cio_start (sch, cdev->private->iccws, 
@@ -64,7 +70,9 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
                 }
                 cdev->private->imask >>= 1;
                 cdev->private->iretry = 5;
+                i++;
         }
+
         return ret;
 }
 
@@ -76,7 +84,7 @@ ccw_device_sense_pgid_start(struct ccw_device *cdev)
         cdev->private->state = DEV_STATE_SENSE_PGID;
         cdev->private->imask = 0x80;
         cdev->private->iretry = 5;
-        memset (&cdev->private->pgid, 0, sizeof (struct pgid));
+        memset (&cdev->private->pgid, 0, sizeof (cdev->private->pgid));
         ret = __ccw_device_sense_pgid_start(cdev);
         if (ret && ret != -EBUSY)
                 ccw_device_sense_pgid_done(cdev, ret);
@@ -91,6 +99,7 @@ __ccw_device_check_sense_pgid(struct ccw_device *cdev)
 {
         struct subchannel *sch;
         struct irb *irb;
+        int i;
 
         sch = to_subchannel(cdev->dev.parent);
         irb = &cdev->private->irb;
@@ -124,7 +133,8 @@ __ccw_device_check_sense_pgid(struct ccw_device *cdev)
                               sch->schid.sch_no, sch->orb.lpm);
                 return -EACCES;
         }
-        if (cdev->private->pgid.inf.ps.state2 == SNID_STATE2_RESVD_ELSE) {
+        i = 8 - ffs(cdev->private->imask);
+        if (cdev->private->pgid[i].inf.ps.state2 == SNID_STATE2_RESVD_ELSE) {
                 CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel 0.%x.%04x "
                               "is reserved by someone else\n",
                               cdev->private->devno, sch->schid.ssid,
@@ -162,12 +172,6 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
         memset(&cdev->private->irb, 0, sizeof(struct irb));
         switch (ret) {
         /* 0, -ETIME, -EOPNOTSUPP, -EAGAIN, -EACCES or -EUSERS */
-        case 0:                 /* Sense Path Group ID successful. */
-                if (cdev->private->pgid.inf.ps.state1 == SNID_STATE1_RESET)
-                        memcpy(&cdev->private->pgid, &css[0]->global_pgid,
-                               sizeof(struct pgid));
-                ccw_device_sense_pgid_done(cdev, 0);
-                break;
         case -EOPNOTSUPP:       /* Sense Path Group ID not supported */
                 ccw_device_sense_pgid_done(cdev, -EOPNOTSUPP);
                 break;
@@ -176,13 +180,15 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
                 break;
         case -EACCES:           /* channel is not operational. */
                 sch->lpm &= ~cdev->private->imask;
+                /* Fall through. */
+        case 0:                 /* Sense Path Group ID successful. */
                 cdev->private->imask >>= 1;
                 cdev->private->iretry = 5;
                 /* Fall through. */
         case -EAGAIN:           /* Try again. */
                 ret = __ccw_device_sense_pgid_start(cdev);
                 if (ret != 0 && ret != -EBUSY)
-                        ccw_device_sense_pgid_done(cdev, -ENODEV);
+                        ccw_device_sense_pgid_done(cdev, ret);
                 break;
         case -EUSERS:           /* device is reserved for someone else. */
                 ccw_device_sense_pgid_done(cdev, -EUSERS);
@@ -203,20 +209,20 @@ __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func)
         sch = to_subchannel(cdev->dev.parent);
 
         /* Setup sense path group id channel program. */
-        cdev->private->pgid.inf.fc = func;
+        cdev->private->pgid[0].inf.fc = func;
         ccw = cdev->private->iccws;
         if (!cdev->private->flags.pgid_single) {
-                cdev->private->pgid.inf.fc |= SPID_FUNC_MULTI_PATH;
+                cdev->private->pgid[0].inf.fc |= SPID_FUNC_MULTI_PATH;
                 ccw->cmd_code = CCW_CMD_SUSPEND_RECONN;
                 ccw->cda = 0;
                 ccw->count = 0;
                 ccw->flags = CCW_FLAG_SLI | CCW_FLAG_CC;
                 ccw++;
         } else
-                cdev->private->pgid.inf.fc |= SPID_FUNC_SINGLE_PATH;
+                cdev->private->pgid[0].inf.fc |= SPID_FUNC_SINGLE_PATH;
 
         ccw->cmd_code = CCW_CMD_SET_PGID;
-        ccw->cda = (__u32) __pa (&cdev->private->pgid);
+        ccw->cda = (__u32) __pa (&cdev->private->pgid[0]);
         ccw->count = sizeof (struct pgid);
         ccw->flags = CCW_FLAG_SLI;
 
@@ -244,6 +250,48 @@ __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func)
 }
 
 /*
+ * Helper function to send a nop ccw down a path.
+ */
+static int __ccw_device_do_nop(struct ccw_device *cdev)
+{
+        struct subchannel *sch;
+        struct ccw1 *ccw;
+        int ret;
+
+        sch = to_subchannel(cdev->dev.parent);
+
+        /* Setup nop channel program. */
+        ccw = cdev->private->iccws;
+        ccw->cmd_code = CCW_CMD_NOOP;
+        ccw->cda = 0;
+        ccw->count = 0;
+        ccw->flags = CCW_FLAG_SLI;
+
+        /* Reset device status. */
+        memset(&cdev->private->irb, 0, sizeof(struct irb));
+
+        /* Try multiple times. */
+        ret = -ENODEV;
+        if (cdev->private->iretry > 0) {
+                cdev->private->iretry--;
+                ret = cio_start (sch, cdev->private->iccws,
+                                 cdev->private->imask);
+                /* ret is 0, -EBUSY, -EACCES or -ENODEV */
+                if ((ret != -EACCES) && (ret != -ENODEV))
+                        return ret;
+        }
+        /* nop command failed on this path. Switch it off. */
+        sch->lpm &= ~cdev->private->imask;
+        sch->vpm &= ~cdev->private->imask;
+        CIO_MSG_EVENT(2, "NOP - Device %04x on Subchannel "
+                      "0.%x.%04x, lpm %02X, became 'not operational'\n",
+                      cdev->private->devno, sch->schid.ssid,
+                      sch->schid.sch_no, cdev->private->imask);
+        return ret;
+}
+
+
+/*
  * Called from interrupt context to check if a valid answer
  * to Set Path Group ID was received.
  */
@@ -282,6 +330,29 @@ __ccw_device_check_pgid(struct ccw_device *cdev)
         return 0;
 }
 
+/*
+ * Called from interrupt context to check the path status after a nop has
+ * been send.
+ */
+static int __ccw_device_check_nop(struct ccw_device *cdev)
+{
+        struct subchannel *sch;
+        struct irb *irb;
+
+        sch = to_subchannel(cdev->dev.parent);
+        irb = &cdev->private->irb;
+        if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC))
+                return -ETIME;
+        if (irb->scsw.cc == 3) {
+                CIO_MSG_EVENT(2, "NOP - Device %04x on Subchannel 0.%x.%04x,"
+                              " lpm %02X, became 'not operational'\n",
+                              cdev->private->devno, sch->schid.ssid,
+                              sch->schid.sch_no, cdev->private->imask);
+                return -EACCES;
+        }
+        return 0;
+}
+
 static void
 __ccw_device_verify_start(struct ccw_device *cdev)
 {
@@ -296,9 +367,12 @@ __ccw_device_verify_start(struct ccw_device *cdev)
                         if ((sch->vpm & imask) != (sch->lpm & imask))
                                 break;
                 cdev->private->imask = imask;
-                func = (sch->vpm & imask) ?
-                        SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH;
-                ret = __ccw_device_do_pgid(cdev, func);
+                if (cdev->private->options.pgroup) {
+                        func = (sch->vpm & imask) ?
+                                SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH;
+                        ret = __ccw_device_do_pgid(cdev, func);
+                } else
+                        ret = __ccw_device_do_nop(cdev);
                 if (ret == 0 || ret == -EBUSY)
                         return;
                 cdev->private->iretry = 5;
@@ -327,7 +401,10 @@ ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event)
         if (ccw_device_accumulate_and_sense(cdev, irb) != 0)
                 return;
         sch = to_subchannel(cdev->dev.parent);
-        ret = __ccw_device_check_pgid(cdev);
+        if (cdev->private->options.pgroup)
+                ret = __ccw_device_check_pgid(cdev);
+        else
+                ret = __ccw_device_check_nop(cdev);
         memset(&cdev->private->irb, 0, sizeof(struct irb));
         switch (ret) {
         /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */
@@ -345,11 +422,10 @@ ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event)
                  * One of those strange devices which claim to be able
                  * to do multipathing but not for Set Path Group ID.
                  */
-                if (cdev->private->flags.pgid_single) {
-                        ccw_device_verify_done(cdev, -EOPNOTSUPP);
-                        break;
-                }
-                cdev->private->flags.pgid_single = 1;
+                if (cdev->private->flags.pgid_single)
+                        cdev->private->options.pgroup = 0;
+                else
+                        cdev->private->flags.pgid_single = 1;
                 /* fall through. */
         case -EAGAIN:           /* Try again. */
                 __ccw_device_verify_start(cdev);
diff --git a/drivers/s390/cio/device_status.c b/drivers/s390/cio/device_status.c
index 14bef2c179bf..caf148d5caad 100644
--- a/drivers/s390/cio/device_status.c
+++ b/drivers/s390/cio/device_status.c
@@ -67,8 +67,7 @@ ccw_device_path_notoper(struct ccw_device *cdev)
                       sch->schib.pmcw.pnom);
 
         sch->lpm &= ~sch->schib.pmcw.pnom;
-        if (cdev->private->options.pgroup)
-                cdev->private->flags.doverify = 1;
+        cdev->private->flags.doverify = 1;
 }
 
 /*
@@ -180,7 +179,7 @@ ccw_device_accumulate_esw(struct ccw_device *cdev, struct irb *irb)
         cdev_irb->esw.esw0.erw.auth = irb->esw.esw0.erw.auth;
         /* Copy path verification required flag. */
         cdev_irb->esw.esw0.erw.pvrf = irb->esw.esw0.erw.pvrf;
-        if (irb->esw.esw0.erw.pvrf && cdev->private->options.pgroup)
+        if (irb->esw.esw0.erw.pvrf)
                 cdev->private->flags.doverify = 1;
         /* Copy concurrent sense bit. */
         cdev_irb->esw.esw0.erw.cons = irb->esw.esw0.erw.cons;
@@ -354,7 +353,7 @@ ccw_device_accumulate_basic_sense(struct ccw_device *cdev, struct irb *irb)
         }
         /* Check if path verification is required. */
         if (ccw_device_accumulate_esw_valid(irb) &&
-            irb->esw.esw0.erw.pvrf && cdev->private->options.pgroup) 
+            irb->esw.esw0.erw.pvrf)
                 cdev->private->flags.doverify = 1;
 }
 
diff --git a/drivers/s390/cio/qdio.c b/drivers/s390/cio/qdio.c
index b70039af70d6..7c93a8798d23 100644
--- a/drivers/s390/cio/qdio.c
+++ b/drivers/s390/cio/qdio.c
@@ -2735,7 +2735,7 @@ qdio_free(struct ccw_device *cdev)
         QDIO_DBF_TEXT1(0,trace,dbf_text);
         QDIO_DBF_TEXT0(0,setup,dbf_text);
 
-        cdev->private->qdio_data = 0;
+        cdev->private->qdio_data = NULL;
 
         up(&irq_ptr->setting_up_sema);