[S390] cio: move irritating comment.
[safe/jmp/linux-2.6] / drivers / s390 / cio / device.c
index 94bdd4d..fc0c0ab 100644 (file)
@@ -2,8 +2,7 @@
  *  drivers/s390/cio/device.c
  *  bus driver for ccw devices
  *
- *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
- *                      IBM Corporation
+ *    Copyright IBM Corp. 2002,2008
  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
  *              Cornelia Huck (cornelia.huck@de.ibm.com)
  *              Martin Schwidefsky (schwidefsky@de.ibm.com)
 #include <linux/list.h>
 #include <linux/device.h>
 #include <linux/workqueue.h>
+#include <linux/timer.h>
 
 #include <asm/ccwdev.h>
 #include <asm/cio.h>
 #include <asm/param.h>         /* HZ */
+#include <asm/cmb.h>
+#include <asm/isc.h>
 
+#include "chp.h"
 #include "cio.h"
+#include "cio_debug.h"
 #include "css.h"
 #include "device.h"
 #include "ioasm.h"
+#include "io_sch.h"
+#include "blacklist.h"
+
+static struct timer_list recovery_timer;
+static DEFINE_SPINLOCK(recovery_lock);
+static int recovery_phase;
+static const unsigned long recovery_delay[] = { 3, 30, 300 };
 
 /******************* bus type handling ***********************/
 
@@ -55,13 +66,12 @@ ccw_bus_match (struct device * dev, struct device_driver * drv)
 /* Store modalias string delimited by prefix/suffix string into buffer with
  * specified size. Return length of resulting string (excluding trailing '\0')
  * even if string doesn't fit buffer (snprintf semantics). */
-static int snprint_alias(char *buf, size_t size, const char *prefix,
+static int snprint_alias(char *buf, size_t size,
                         struct ccw_device_id *id, const char *suffix)
 {
        int len;
 
-       len = snprintf(buf, size, "%sccw:t%04Xm%02X", prefix, id->cu_type,
-                      id->cu_model);
+       len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
        if (len > size)
                return len;
        buf += len;
@@ -78,91 +88,74 @@ static int snprint_alias(char *buf, size_t size, const char *prefix,
 
 /* Set up environment variables for ccw device uevent. Return 0 on success,
  * non-zero otherwise. */
-static int ccw_uevent(struct device *dev, char **envp, int num_envp,
-                     char *buffer, int buffer_size)
+static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
        struct ccw_device *cdev = to_ccwdev(dev);
        struct ccw_device_id *id = &(cdev->id);
-       int i = 0;
-       int len;
+       int ret;
+       char modalias_buf[30];
 
        /* CU_TYPE= */
-       len = snprintf(buffer, buffer_size, "CU_TYPE=%04X", id->cu_type) + 1;
-       if (len > buffer_size || i >= num_envp)
-               return -ENOMEM;
-       envp[i++] = buffer;
-       buffer += len;
-       buffer_size -= len;
+       ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
+       if (ret)
+               return ret;
 
        /* CU_MODEL= */
-       len = snprintf(buffer, buffer_size, "CU_MODEL=%02X", id->cu_model) + 1;
-       if (len > buffer_size || i >= num_envp)
-               return -ENOMEM;
-       envp[i++] = buffer;
-       buffer += len;
-       buffer_size -= len;
+       ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
+       if (ret)
+               return ret;
 
        /* The next two can be zero, that's ok for us */
        /* DEV_TYPE= */
-       len = snprintf(buffer, buffer_size, "DEV_TYPE=%04X", id->dev_type) + 1;
-       if (len > buffer_size || i >= num_envp)
-               return -ENOMEM;
-       envp[i++] = buffer;
-       buffer += len;
-       buffer_size -= len;
+       ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
+       if (ret)
+               return ret;
 
        /* DEV_MODEL= */
-       len = snprintf(buffer, buffer_size, "DEV_MODEL=%02X",
-                       (unsigned char) id->dev_model) + 1;
-       if (len > buffer_size || i >= num_envp)
-               return -ENOMEM;
-       envp[i++] = buffer;
-       buffer += len;
-       buffer_size -= len;
+       ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
+       if (ret)
+               return ret;
 
        /* MODALIAS=  */
-       len = snprint_alias(buffer, buffer_size, "MODALIAS=", id, "") + 1;
-       if (len > buffer_size || i >= num_envp)
-               return -ENOMEM;
-       envp[i++] = buffer;
-       buffer += len;
-       buffer_size -= len;
-
-       envp[i] = NULL;
-
-       return 0;
+       snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
+       ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
+       return ret;
 }
 
 struct bus_type ccw_bus_type;
 
-static int io_subchannel_probe (struct subchannel *);
-static int io_subchannel_remove (struct subchannel *);
-void io_subchannel_irq (struct device *);
-static int io_subchannel_notify(struct device *, int);
-static void io_subchannel_verify(struct device *);
-static void io_subchannel_ioterm(struct device *);
+static void io_subchannel_irq(struct subchannel *);
+static int io_subchannel_probe(struct subchannel *);
+static int io_subchannel_remove(struct subchannel *);
 static void io_subchannel_shutdown(struct subchannel *);
+static int io_subchannel_sch_event(struct subchannel *, int);
+static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
+                                  int);
 
-struct css_driver io_subchannel_driver = {
-       .subchannel_type = SUBCHANNEL_TYPE_IO,
-       .drv = {
-               .name = "io_subchannel",
-               .bus  = &css_bus_type,
-       },
+static struct css_device_id io_subchannel_ids[] = {
+       { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
+       { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(css, io_subchannel_ids);
+
+static struct css_driver io_subchannel_driver = {
+       .owner = THIS_MODULE,
+       .subchannel_type = io_subchannel_ids,
+       .name = "io_subchannel",
        .irq = io_subchannel_irq,
-       .notify = io_subchannel_notify,
-       .verify = io_subchannel_verify,
-       .termination = io_subchannel_ioterm,
+       .sch_event = io_subchannel_sch_event,
+       .chp_event = io_subchannel_chp_event,
        .probe = io_subchannel_probe,
        .remove = io_subchannel_remove,
        .shutdown = io_subchannel_shutdown,
 };
 
 struct workqueue_struct *ccw_device_work;
-struct workqueue_struct *ccw_device_notify_work;
 wait_queue_head_t ccw_device_init_wq;
 atomic_t ccw_device_init_count;
 
+static void recovery_func(unsigned long data);
+
 static int __init
 init_ccw_bus_type (void)
 {
@@ -170,15 +163,11 @@ init_ccw_bus_type (void)
 
        init_waitqueue_head(&ccw_device_init_wq);
        atomic_set(&ccw_device_init_count, 0);
+       setup_timer(&recovery_timer, recovery_func, 0);
 
        ccw_device_work = create_singlethread_workqueue("cio");
        if (!ccw_device_work)
                return -ENOMEM; /* FIXME: better errno ? */
-       ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
-       if (!ccw_device_notify_work) {
-               ret = -ENOMEM; /* FIXME: better errno ? */
-               goto out_err;
-       }
        slow_path_wq = create_singlethread_workqueue("kslowcrw");
        if (!slow_path_wq) {
                ret = -ENOMEM; /* FIXME: better errno ? */
@@ -187,7 +176,8 @@ init_ccw_bus_type (void)
        if ((ret = bus_register (&ccw_bus_type)))
                goto out_err;
 
-       if ((ret = driver_register(&io_subchannel_driver.drv)))
+       ret = css_driver_register(&io_subchannel_driver);
+       if (ret)
                goto out_err;
 
        wait_event(ccw_device_init_wq,
@@ -197,8 +187,6 @@ init_ccw_bus_type (void)
 out_err:
        if (ccw_device_work)
                destroy_workqueue(ccw_device_work);
-       if (ccw_device_notify_work)
-               destroy_workqueue(ccw_device_notify_work);
        if (slow_path_wq)
                destroy_workqueue(slow_path_wq);
        return ret;
@@ -207,9 +195,8 @@ out_err:
 static void __exit
 cleanup_ccw_bus_type (void)
 {
-       driver_unregister(&io_subchannel_driver.drv);
+       css_driver_unregister(&io_subchannel_driver);
        bus_unregister(&ccw_bus_type);
-       destroy_workqueue(ccw_device_notify_work);
        destroy_workqueue(ccw_device_work);
 }
 
@@ -230,13 +217,18 @@ static ssize_t
 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 {
        struct subchannel *sch = to_subchannel(dev);
-       struct ssd_info *ssd = &sch->ssd_info;
+       struct chsc_ssd_info *ssd = &sch->ssd_info;
        ssize_t ret = 0;
        int chp;
+       int mask;
 
-       for (chp = 0; chp < 8; chp++)
-               ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
-
+       for (chp = 0; chp < 8; chp++) {
+               mask = 0x80 >> chp;
+               if (ssd->path_mask & mask)
+                       ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
+               else
+                       ret += sprintf(buf + ret, "00 ");
+       }
        ret += sprintf (buf+ret, "\n");
        return min((ssize_t)PAGE_SIZE, ret);
 }
@@ -281,7 +273,7 @@ modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
        struct ccw_device_id *id = &(cdev->id);
        int len;
 
-       len = snprint_alias(buf, PAGE_SIZE, "", id, "\n") + 1;
+       len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 
        return len > PAGE_SIZE ? PAGE_SIZE : len;
 }
@@ -294,24 +286,74 @@ online_show (struct device *dev, struct device_attribute *attr, char *buf)
        return sprintf(buf, cdev->online ? "1\n" : "0\n");
 }
 
+int ccw_device_is_orphan(struct ccw_device *cdev)
+{
+       return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
+}
+
+static void ccw_device_unregister(struct ccw_device *cdev)
+{
+       if (test_and_clear_bit(1, &cdev->private->registered))
+               device_del(&cdev->dev);
+}
+
+static void ccw_device_remove_orphan_cb(struct work_struct *work)
+{
+       struct ccw_device_private *priv;
+       struct ccw_device *cdev;
+
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
+       ccw_device_unregister(cdev);
+       put_device(&cdev->dev);
+       /* Release cdev reference for workqueue processing. */
+       put_device(&cdev->dev);
+}
+
+static void ccw_device_call_sch_unregister(struct work_struct *work);
+
 static void
 ccw_device_remove_disconnected(struct ccw_device *cdev)
 {
-       struct subchannel *sch;
+       unsigned long flags;
+
        /*
         * Forced offline in disconnected state means
         * 'throw away device'.
         */
-       sch = to_subchannel(cdev->dev.parent);
-       css_sch_device_unregister(sch);
-       /* Reset intparm to zeroes. */
-       sch->schib.pmcw.intparm = 0;
-       cio_modify(sch);
-       put_device(&sch->dev);
+       /* Get cdev reference for workqueue processing. */
+       if (!get_device(&cdev->dev))
+               return;
+       if (ccw_device_is_orphan(cdev)) {
+               /*
+                * Deregister ccw device.
+                * Unfortunately, we cannot do this directly from the
+                * attribute method.
+                */
+               spin_lock_irqsave(cdev->ccwlock, flags);
+               cdev->private->state = DEV_STATE_NOT_OPER;
+               spin_unlock_irqrestore(cdev->ccwlock, flags);
+               PREPARE_WORK(&cdev->private->kick_work,
+                               ccw_device_remove_orphan_cb);
+       } else
+               /* Deregister subchannel, which will kill the ccw device. */
+               PREPARE_WORK(&cdev->private->kick_work,
+                               ccw_device_call_sch_unregister);
+       queue_work(slow_path_wq, &cdev->private->kick_work);
 }
 
-int
-ccw_device_set_offline(struct ccw_device *cdev)
+/**
+ * ccw_device_set_offline() - disable a ccw device for I/O
+ * @cdev: target ccw device
+ *
+ * This function calls the driver's set_offline() function for @cdev, if
+ * given, and then disables @cdev.
+ * Returns:
+ *   %0 on success and a negative error value on failure.
+ * Context:
+ *  enabled, ccw device lock not held
+ */
+int ccw_device_set_offline(struct ccw_device *cdev)
 {
        int ret;
 
@@ -340,15 +382,28 @@ ccw_device_set_offline(struct ccw_device *cdev)
        if (ret == 0)
                wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
        else {
-               pr_debug("ccw_device_offline returned %d, device %s\n",
-                        ret, cdev->dev.bus_id);
+               CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
+                             "device 0.%x.%04x\n",
+                             ret, cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno);
                cdev->online = 1;
        }
        return ret;
 }
 
-int
-ccw_device_set_online(struct ccw_device *cdev)
+/**
+ * ccw_device_set_online() - enable a ccw device for I/O
+ * @cdev: target ccw device
+ *
+ * This function first enables @cdev and then calls the driver's set_online()
+ * function for @cdev, if given. If set_online() returns an error, @cdev is
+ * disabled again.
+ * Returns:
+ *   %0 on success and a negative error value on failure.
+ * Context:
+ *  enabled, ccw device lock not held
+ */
+int ccw_device_set_online(struct ccw_device *cdev)
 {
        int ret;
 
@@ -363,8 +418,10 @@ ccw_device_set_online(struct ccw_device *cdev)
        if (ret == 0)
                wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
        else {
-               pr_debug("ccw_device_online returned %d, device %s\n",
-                        ret, cdev->dev.bus_id);
+               CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
+                             "device 0.%x.%04x\n",
+                             ret, cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno);
                return ret;
        }
        if (cdev->private->state != DEV_STATE_ONLINE)
@@ -378,18 +435,67 @@ ccw_device_set_online(struct ccw_device *cdev)
        spin_unlock_irq(cdev->ccwlock);
        if (ret == 0)
                wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
-       else 
-               pr_debug("ccw_device_offline returned %d, device %s\n",
-                        ret, cdev->dev.bus_id);
+       else
+               CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
+                             "device 0.%x.%04x\n",
+                             ret, cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno);
        return (ret == 0) ? -ENODEV : ret;
 }
 
-static ssize_t
-online_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+static void online_store_handle_offline(struct ccw_device *cdev)
+{
+       if (cdev->private->state == DEV_STATE_DISCONNECTED)
+               ccw_device_remove_disconnected(cdev);
+       else if (cdev->drv && cdev->drv->set_offline)
+               ccw_device_set_offline(cdev);
+}
+
+static int online_store_recog_and_online(struct ccw_device *cdev)
+{
+       int ret;
+
+       /* Do device recognition, if needed. */
+       if (cdev->id.cu_type == 0) {
+               ret = ccw_device_recognition(cdev);
+               if (ret) {
+                       CIO_MSG_EVENT(0, "Couldn't start recognition "
+                                     "for device 0.%x.%04x (ret=%d)\n",
+                                     cdev->private->dev_id.ssid,
+                                     cdev->private->dev_id.devno, ret);
+                       return ret;
+               }
+               wait_event(cdev->private->wait_q,
+                          cdev->private->flags.recog_done);
+       }
+       if (cdev->drv && cdev->drv->set_online)
+               ccw_device_set_online(cdev);
+       return 0;
+}
+static int online_store_handle_online(struct ccw_device *cdev, int force)
+{
+       int ret;
+
+       ret = online_store_recog_and_online(cdev);
+       if (ret)
+               return ret;
+       if (force && cdev->private->state == DEV_STATE_BOXED) {
+               ret = ccw_device_stlck(cdev);
+               if (ret)
+                       return ret;
+               if (cdev->id.cu_type == 0)
+                       cdev->private->state = DEV_STATE_NOT_OPER;
+               online_store_recog_and_online(cdev);
+       }
+       return 0;
+}
+
+static ssize_t online_store (struct device *dev, struct device_attribute *attr,
+                            const char *buf, size_t count)
 {
        struct ccw_device *cdev = to_ccwdev(dev);
-       int i, force, ret;
-       char *tmp;
+       int force, ret;
+       unsigned long i;
 
        if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
                return -EAGAIN;
@@ -401,59 +507,31 @@ online_store (struct device *dev, struct device_attribute *attr, const char *buf
        if (!strncmp(buf, "force\n", count)) {
                force = 1;
                i = 1;
+               ret = 0;
        } else {
                force = 0;
-               i = simple_strtoul(buf, &tmp, 16);
+               ret = strict_strtoul(buf, 16, &i);
        }
-       if (i == 1) {
-               /* Do device recognition, if needed. */
-               if (cdev->id.cu_type == 0) {
-                       ret = ccw_device_recognition(cdev);
-                       if (ret) {
-                               printk(KERN_WARNING"Couldn't start recognition "
-                                      "for device %s (ret=%d)\n",
-                                      cdev->dev.bus_id, ret);
-                               goto out;
-                       }
-                       wait_event(cdev->private->wait_q,
-                                  cdev->private->flags.recog_done);
-               }
-               if (cdev->drv && cdev->drv->set_online)
-                       ccw_device_set_online(cdev);
-       } else if (i == 0) {
-               if (cdev->private->state == DEV_STATE_DISCONNECTED)
-                       ccw_device_remove_disconnected(cdev);
-               else if (cdev->drv && cdev->drv->set_offline)
-                       ccw_device_set_offline(cdev);
-       }
-       if (force && cdev->private->state == DEV_STATE_BOXED) {
-               ret = ccw_device_stlck(cdev);
-               if (ret) {
-                       printk(KERN_WARNING"ccw_device_stlck for device %s "
-                              "returned %d!\n", cdev->dev.bus_id, ret);
-                       goto out;
-               }
-               /* Do device recognition, if needed. */
-               if (cdev->id.cu_type == 0) {
-                       cdev->private->state = DEV_STATE_NOT_OPER;
-                       ret = ccw_device_recognition(cdev);
-                       if (ret) {
-                               printk(KERN_WARNING"Couldn't start recognition "
-                                      "for device %s (ret=%d)\n",
-                                      cdev->dev.bus_id, ret);
-                               goto out;
-                       }
-                       wait_event(cdev->private->wait_q,
-                                  cdev->private->flags.recog_done);
-               }
-               if (cdev->drv && cdev->drv->set_online)
-                       ccw_device_set_online(cdev);
+       if (ret)
+               goto out;
+       switch (i) {
+       case 0:
+               online_store_handle_offline(cdev);
+               ret = count;
+               break;
+       case 1:
+               ret = online_store_handle_online(cdev, force);
+               if (!ret)
+                       ret = count;
+               break;
+       default:
+               ret = -EINVAL;
        }
-       out:
+out:
        if (cdev->drv)
                module_put(cdev->drv->owner);
        atomic_set(&cdev->private->onoff, 0);
-       return count;
+       return ret;
 }
 
 static ssize_t
@@ -462,6 +540,8 @@ available_show (struct device *dev, struct device_attribute *attr, char *buf)
        struct ccw_device *cdev = to_ccwdev(dev);
        struct subchannel *sch;
 
+       if (ccw_device_is_orphan(cdev))
+               return sprintf(buf, "no device\n");
        switch (cdev->private->state) {
        case DEV_STATE_BOXED:
                return sprintf(buf, "boxed\n");
@@ -485,25 +565,18 @@ static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 static DEVICE_ATTR(online, 0644, online_show, online_store);
-extern struct device_attribute dev_attr_cmb_enable;
 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 
-static struct attribute * subch_attrs[] = {
+static struct attribute *io_subchannel_attrs[] = {
        &dev_attr_chpids.attr,
        &dev_attr_pimpampom.attr,
        NULL,
 };
 
-static struct attribute_group subch_attr_group = {
-       .attrs = subch_attrs,
+static struct attribute_group io_subchannel_attr_group = {
+       .attrs = io_subchannel_attrs,
 };
 
-static inline int
-subchannel_add_files (struct device *dev)
-{
-       return sysfs_create_group(&dev->kobj, &subch_attr_group);
-}
-
 static struct attribute * ccwdev_attrs[] = {
        &dev_attr_devtype.attr,
        &dev_attr_cutype.attr,
@@ -518,22 +591,14 @@ static struct attribute_group ccwdev_attr_group = {
        .attrs = ccwdev_attrs,
 };
 
-static inline int
-device_add_files (struct device *dev)
-{
-       return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
-}
-
-static inline void
-device_remove_files(struct device *dev)
-{
-       sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
-}
+static struct attribute_group *ccwdev_attr_groups[] = {
+       &ccwdev_attr_group,
+       NULL,
+};
 
 /* this is a simple abstraction for device_register that sets the
  * correct bus type and adds the bus specific files */
-int
-ccw_device_register(struct ccw_device *cdev)
+static int ccw_device_register(struct ccw_device *cdev)
 {
        struct device *dev = &cdev->dev;
        int ret;
@@ -544,10 +609,6 @@ ccw_device_register(struct ccw_device *cdev)
                return ret;
 
        set_bit(1, &cdev->private->registered);
-       if ((ret = device_add_files(dev))) {
-               if (test_and_clear_bit(1, &cdev->private->registered))
-                       device_del(dev);
-       }
        return ret;
 }
 
@@ -564,11 +625,10 @@ match_devno(struct device * dev, void * data)
 
        cdev = to_ccwdev(dev);
        if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
+           !ccw_device_is_orphan(cdev) &&
            ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
-           (cdev != d->sibling)) {
-               cdev->private->state = DEV_STATE_NOT_OPER;
+           (cdev != d->sibling))
                return 1;
-       }
        return 0;
 }
 
@@ -585,82 +645,56 @@ static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
        return dev ? to_ccwdev(dev) : NULL;
 }
 
-static void
-ccw_device_add_changed(void *data)
+static int match_orphan(struct device *dev, void *data)
+{
+       struct ccw_dev_id *dev_id;
+       struct ccw_device *cdev;
+
+       dev_id = data;
+       cdev = to_ccwdev(dev);
+       return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
+}
+
+static struct ccw_device *
+get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
+                             struct ccw_dev_id *dev_id)
 {
+       struct device *dev;
 
+       dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
+                               match_orphan);
+
+       return dev ? to_ccwdev(dev) : NULL;
+}
+
+static void
+ccw_device_add_changed(struct work_struct *work)
+{
+       struct ccw_device_private *priv;
        struct ccw_device *cdev;
 
-       cdev = data;
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
        if (device_add(&cdev->dev)) {
                put_device(&cdev->dev);
                return;
        }
        set_bit(1, &cdev->private->registered);
-       if (device_add_files(&cdev->dev)) {
-               if (test_and_clear_bit(1, &cdev->private->registered))
-                       device_unregister(&cdev->dev);
-       }
 }
 
-extern int css_get_ssd_info(struct subchannel *sch);
-
-void
-ccw_device_do_unreg_rereg(void *data)
+void ccw_device_do_unreg_rereg(struct work_struct *work)
 {
+       struct ccw_device_private *priv;
        struct ccw_device *cdev;
        struct subchannel *sch;
-       int need_rename;
 
-       cdev = data;
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
        sch = to_subchannel(cdev->dev.parent);
-       if (cdev->private->dev_id.devno != sch->schib.pmcw.dev) {
-               /*
-                * The device number has changed. This is usually only when
-                * a device has been detached under VM and then re-appeared
-                * on another subchannel because of a different attachment
-                * order than before. Ideally, we should should just switch
-                * subchannels, but unfortunately, this is not possible with
-                * the current implementation.
-                * Instead, we search for the old subchannel for this device
-                * number and deregister so there are no collisions with the
-                * newly registered ccw_device.
-                * FIXME: Find another solution so the block layer doesn't
-                *        get possibly sick...
-                */
-               struct ccw_device *other_cdev;
-               struct ccw_dev_id dev_id;
-
-               need_rename = 1;
-               dev_id.devno = sch->schib.pmcw.dev;
-               dev_id.ssid = sch->schid.ssid;
-               other_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
-               if (other_cdev) {
-                       struct subchannel *other_sch;
-
-                       other_sch = to_subchannel(other_cdev->dev.parent);
-                       if (get_device(&other_sch->dev)) {
-                               stsch(other_sch->schid, &other_sch->schib);
-                               if (other_sch->schib.pmcw.dnv) {
-                                       other_sch->schib.pmcw.intparm = 0;
-                                       cio_modify(other_sch);
-                               }
-                               css_sch_device_unregister(other_sch);
-                       }
-               }
-               /* Update ssd info here. */
-               css_get_ssd_info(sch);
-               cdev->private->dev_id.devno = sch->schib.pmcw.dev;
-       } else
-               need_rename = 0;
-       device_remove_files(&cdev->dev);
-       if (test_and_clear_bit(1, &cdev->private->registered))
-               device_del(&cdev->dev);
-       if (need_rename)
-               snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
-                         sch->schid.ssid, sch->schib.pmcw.dev);
+
+       ccw_device_unregister(cdev);
        PREPARE_WORK(&cdev->private->kick_work,
-                    ccw_device_add_changed, cdev);
+                    ccw_device_add_changed);
        queue_work(ccw_device_work, &cdev->private->kick_work);
 }
 
@@ -674,33 +708,236 @@ ccw_device_release(struct device *dev)
        kfree(cdev);
 }
 
+static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
+{
+       struct ccw_device *cdev;
+
+       cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
+       if (cdev) {
+               cdev->private = kzalloc(sizeof(struct ccw_device_private),
+                                       GFP_KERNEL | GFP_DMA);
+               if (cdev->private)
+                       return cdev;
+       }
+       kfree(cdev);
+       return ERR_PTR(-ENOMEM);
+}
+
+static int io_subchannel_initialize_dev(struct subchannel *sch,
+                                       struct ccw_device *cdev)
+{
+       cdev->private->cdev = cdev;
+       atomic_set(&cdev->private->onoff, 0);
+       cdev->dev.parent = &sch->dev;
+       cdev->dev.release = ccw_device_release;
+       INIT_WORK(&cdev->private->kick_work, NULL);
+       cdev->dev.groups = ccwdev_attr_groups;
+       /* Do first half of device_register. */
+       device_initialize(&cdev->dev);
+       if (!get_device(&sch->dev)) {
+               if (cdev->dev.release)
+                       cdev->dev.release(&cdev->dev);
+               return -ENODEV;
+       }
+       return 0;
+}
+
+static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
+{
+       struct ccw_device *cdev;
+       int ret;
+
+       cdev = io_subchannel_allocate_dev(sch);
+       if (!IS_ERR(cdev)) {
+               ret = io_subchannel_initialize_dev(sch, cdev);
+               if (ret) {
+                       kfree(cdev);
+                       cdev = ERR_PTR(ret);
+               }
+       }
+       return cdev;
+}
+
+static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
+
+static void sch_attach_device(struct subchannel *sch,
+                             struct ccw_device *cdev)
+{
+       css_update_ssd_info(sch);
+       spin_lock_irq(sch->lock);
+       sch_set_cdev(sch, cdev);
+       cdev->private->schid = sch->schid;
+       cdev->ccwlock = sch->lock;
+       ccw_device_trigger_reprobe(cdev);
+       spin_unlock_irq(sch->lock);
+}
+
+static void sch_attach_disconnected_device(struct subchannel *sch,
+                                          struct ccw_device *cdev)
+{
+       struct subchannel *other_sch;
+       int ret;
+
+       other_sch = to_subchannel(get_device(cdev->dev.parent));
+       ret = device_move(&cdev->dev, &sch->dev);
+       if (ret) {
+               CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
+                             "(ret=%d)!\n", cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno, ret);
+               put_device(&other_sch->dev);
+               return;
+       }
+       sch_set_cdev(other_sch, NULL);
+       /* No need to keep a subchannel without ccw device around. */
+       css_sch_device_unregister(other_sch);
+       put_device(&other_sch->dev);
+       sch_attach_device(sch, cdev);
+}
+
+static void sch_attach_orphaned_device(struct subchannel *sch,
+                                      struct ccw_device *cdev)
+{
+       int ret;
+
+       /* Try to move the ccw device to its new subchannel. */
+       ret = device_move(&cdev->dev, &sch->dev);
+       if (ret) {
+               CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
+                             "failed (ret=%d)!\n",
+                             cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno, ret);
+               return;
+       }
+       sch_attach_device(sch, cdev);
+}
+
+static void sch_create_and_recog_new_device(struct subchannel *sch)
+{
+       struct ccw_device *cdev;
+
+       /* Need to allocate a new ccw device. */
+       cdev = io_subchannel_create_ccwdev(sch);
+       if (IS_ERR(cdev)) {
+               /* OK, we did everything we could... */
+               css_sch_device_unregister(sch);
+               return;
+       }
+       spin_lock_irq(sch->lock);
+       sch_set_cdev(sch, cdev);
+       spin_unlock_irq(sch->lock);
+       /* Start recognition for the new ccw device. */
+       if (io_subchannel_recog(cdev, sch)) {
+               spin_lock_irq(sch->lock);
+               sch_set_cdev(sch, NULL);
+               spin_unlock_irq(sch->lock);
+               if (cdev->dev.release)
+                       cdev->dev.release(&cdev->dev);
+               css_sch_device_unregister(sch);
+       }
+}
+
+
+void ccw_device_move_to_orphanage(struct work_struct *work)
+{
+       struct ccw_device_private *priv;
+       struct ccw_device *cdev;
+       struct ccw_device *replacing_cdev;
+       struct subchannel *sch;
+       int ret;
+       struct channel_subsystem *css;
+       struct ccw_dev_id dev_id;
+
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
+       sch = to_subchannel(cdev->dev.parent);
+       css = to_css(sch->dev.parent);
+       dev_id.devno = sch->schib.pmcw.dev;
+       dev_id.ssid = sch->schid.ssid;
+
+       /*
+        * Move the orphaned ccw device to the orphanage so the replacing
+        * ccw device can take its place on the subchannel.
+        */
+       ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
+       if (ret) {
+               CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
+                             "(ret=%d)!\n", cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno, ret);
+               return;
+       }
+       cdev->ccwlock = css->pseudo_subchannel->lock;
+       /*
+        * Search for the replacing ccw device
+        * - among the disconnected devices
+        * - in the orphanage
+        */
+       replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
+       if (replacing_cdev) {
+               sch_attach_disconnected_device(sch, replacing_cdev);
+               /* Release reference from get_disc_ccwdev_by_dev_id() */
+               put_device(&cdev->dev);
+               return;
+       }
+       replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
+       if (replacing_cdev) {
+               sch_attach_orphaned_device(sch, replacing_cdev);
+               /* Release reference from get_orphaned_ccwdev_by_dev_id() */
+               put_device(&cdev->dev);
+               return;
+       }
+       sch_create_and_recog_new_device(sch);
+}
+
 /*
  * Register recognized device.
  */
 static void
-io_subchannel_register(void *data)
+io_subchannel_register(struct work_struct *work)
 {
+       struct ccw_device_private *priv;
        struct ccw_device *cdev;
        struct subchannel *sch;
        int ret;
        unsigned long flags;
 
-       cdev = data;
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
        sch = to_subchannel(cdev->dev.parent);
-
+       css_update_ssd_info(sch);
+       /*
+        * io_subchannel_register() will also be called after device
+        * recognition has been done for a boxed device (which will already
+        * be registered). We need to reprobe since we may now have sense id
+        * information.
+        */
        if (klist_node_attached(&cdev->dev.knode_parent)) {
-               bus_rescan_devices(&ccw_bus_type);
+               if (!cdev->drv) {
+                       ret = device_reprobe(&cdev->dev);
+                       if (ret)
+                               /* We can't do much here. */
+                               CIO_MSG_EVENT(0, "device_reprobe() returned"
+                                             " %d for 0.%x.%04x\n", ret,
+                                             cdev->private->dev_id.ssid,
+                                             cdev->private->dev_id.devno);
+               }
                goto out;
        }
+       /*
+        * Now we know this subchannel will stay, we can throw
+        * our delayed uevent.
+        */
+       sch->dev.uevent_suppress = 0;
+       kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
        /* make it known to the system */
        ret = ccw_device_register(cdev);
        if (ret) {
-               printk (KERN_WARNING "%s: could not register %s\n",
-                       __func__, cdev->dev.bus_id);
+               CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
+                             cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno, ret);
                put_device(&cdev->dev);
-               spin_lock_irqsave(&sch->lock, flags);
-               sch->dev.driver_data = NULL;
-               spin_unlock_irqrestore(&sch->lock, flags);
+               spin_lock_irqsave(sch->lock, flags);
+               sch_set_cdev(sch, NULL);
+               spin_unlock_irqrestore(sch->lock, flags);
                kfree (cdev->private);
                kfree (cdev);
                put_device(&sch->dev);
@@ -708,11 +945,6 @@ io_subchannel_register(void *data)
                        wake_up(&ccw_device_init_wq);
                return;
        }
-
-       ret = subchannel_add_files(cdev->dev.parent);
-       if (ret)
-               printk(KERN_WARNING "%s: could not add attributes to %s\n",
-                      __func__, sch->dev.bus_id);
        put_device(&cdev->dev);
 out:
        cdev->private->flags.recog_done = 1;
@@ -722,18 +954,25 @@ out:
                wake_up(&ccw_device_init_wq);
 }
 
-void
-ccw_device_call_sch_unregister(void *data)
+static void ccw_device_call_sch_unregister(struct work_struct *work)
 {
-       struct ccw_device *cdev = data;
+       struct ccw_device_private *priv;
+       struct ccw_device *cdev;
        struct subchannel *sch;
 
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       cdev = priv->cdev;
+       /* Get subchannel reference for local processing. */
+       if (!get_device(cdev->dev.parent))
+               return;
        sch = to_subchannel(cdev->dev.parent);
        css_sch_device_unregister(sch);
        /* Reset intparm to zeroes. */
        sch->schib.pmcw.intparm = 0;
        cio_modify(sch);
+       /* Release cdev reference for workqueue processing.*/
        put_device(&cdev->dev);
+       /* Release subchannel reference for local processing. */
        put_device(&sch->dev);
 }
 
@@ -757,8 +996,10 @@ io_subchannel_recog_done(struct ccw_device *cdev)
                        break;
                sch = to_subchannel(cdev->dev.parent);
                PREPARE_WORK(&cdev->private->kick_work,
-                            ccw_device_call_sch_unregister, cdev);
+                            ccw_device_call_sch_unregister);
                queue_work(slow_path_wq, &cdev->private->kick_work);
+               /* Release subchannel reference for asynchronous recognition. */
+               put_device(&sch->dev);
                if (atomic_dec_and_test(&ccw_device_init_count))
                        wake_up(&ccw_device_init_wq);
                break;
@@ -772,7 +1013,7 @@ io_subchannel_recog_done(struct ccw_device *cdev)
                if (!get_device(&cdev->dev))
                        break;
                PREPARE_WORK(&cdev->private->kick_work,
-                            io_subchannel_register, cdev);
+                            io_subchannel_register);
                queue_work(slow_path_wq, &cdev->private->kick_work);
                break;
        }
@@ -784,9 +1025,8 @@ io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
        int rc;
        struct ccw_device_private *priv;
 
-       sch->dev.driver_data = cdev;
-       sch->driver = &io_subchannel_driver;
-       cdev->ccwlock = &sch->lock;
+       sch_set_cdev(sch, cdev);
+       cdev->ccwlock = sch->lock;
 
        /* Init private data. */
        priv = cdev->private;
@@ -799,16 +1039,19 @@ io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
        init_timer(&priv->timer);
 
        /* Set an initial name for the device. */
-       snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
-                 sch->schid.ssid, sch->schib.pmcw.dev);
+       if (cio_is_console(sch->schid))
+               cdev->dev.init_name = cio_get_console_cdev_name(sch);
+       else
+               dev_set_name(&cdev->dev, "0.%x.%04x",
+                            sch->schid.ssid, sch->schib.pmcw.dev);
 
        /* Increase counter of devices currently in recognition. */
        atomic_inc(&ccw_device_init_count);
 
        /* Start async. device sensing. */
-       spin_lock_irq(&sch->lock);
+       spin_lock_irq(sch->lock);
        rc = ccw_device_recognition(cdev);
-       spin_unlock_irq(&sch->lock);
+       spin_unlock_irq(sch->lock);
        if (rc) {
                if (atomic_dec_and_test(&ccw_device_init_count))
                        wake_up(&ccw_device_init_wq);
@@ -816,23 +1059,113 @@ io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
        return rc;
 }
 
-static int
-io_subchannel_probe (struct subchannel *sch)
+static void ccw_device_move_to_sch(struct work_struct *work)
+{
+       struct ccw_device_private *priv;
+       int rc;
+       struct subchannel *sch;
+       struct ccw_device *cdev;
+       struct subchannel *former_parent;
+
+       priv = container_of(work, struct ccw_device_private, kick_work);
+       sch = priv->sch;
+       cdev = priv->cdev;
+       former_parent = ccw_device_is_orphan(cdev) ?
+               NULL : to_subchannel(get_device(cdev->dev.parent));
+       mutex_lock(&sch->reg_mutex);
+       /* Try to move the ccw device to its new subchannel. */
+       rc = device_move(&cdev->dev, &sch->dev);
+       mutex_unlock(&sch->reg_mutex);
+       if (rc) {
+               CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
+                             "0.%x.%04x failed (ret=%d)!\n",
+                             cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno, sch->schid.ssid,
+                             sch->schid.sch_no, rc);
+               css_sch_device_unregister(sch);
+               goto out;
+       }
+       if (former_parent) {
+               spin_lock_irq(former_parent->lock);
+               sch_set_cdev(former_parent, NULL);
+               spin_unlock_irq(former_parent->lock);
+               css_sch_device_unregister(former_parent);
+               /* Reset intparm to zeroes. */
+               former_parent->schib.pmcw.intparm = 0;
+               cio_modify(former_parent);
+       }
+       sch_attach_device(sch, cdev);
+out:
+       if (former_parent)
+               put_device(&former_parent->dev);
+       put_device(&cdev->dev);
+}
+
+static void io_subchannel_irq(struct subchannel *sch)
+{
+       struct ccw_device *cdev;
+
+       cdev = sch_get_cdev(sch);
+
+       CIO_TRACE_EVENT(3, "IRQ");
+       CIO_TRACE_EVENT(3, dev_name(&sch->dev));
+       if (cdev)
+               dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
+}
+
+static void io_subchannel_init_fields(struct subchannel *sch)
+{
+       if (cio_is_console(sch->schid))
+               sch->opm = 0xff;
+       else
+               sch->opm = chp_get_sch_opm(sch);
+       sch->lpm = sch->schib.pmcw.pam & sch->opm;
+       sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
+
+       CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
+                     " - PIM = %02X, PAM = %02X, POM = %02X\n",
+                     sch->schib.pmcw.dev, sch->schid.ssid,
+                     sch->schid.sch_no, sch->schib.pmcw.pim,
+                     sch->schib.pmcw.pam, sch->schib.pmcw.pom);
+       /* Initially set up some fields in the pmcw. */
+       sch->schib.pmcw.ena = 0;
+       sch->schib.pmcw.csense = 1;     /* concurrent sense */
+       if ((sch->lpm & (sch->lpm - 1)) != 0)
+               sch->schib.pmcw.mp = 1; /* multipath mode */
+       /* clean up possible residual cmf stuff */
+       sch->schib.pmcw.mme = 0;
+       sch->schib.pmcw.mbfc = 0;
+       sch->schib.pmcw.mbi = 0;
+       sch->schib.mba = 0;
+}
+
+static int io_subchannel_probe(struct subchannel *sch)
 {
        struct ccw_device *cdev;
        int rc;
        unsigned long flags;
+       struct ccw_dev_id dev_id;
 
-       if (sch->dev.driver_data) {
+       cdev = sch_get_cdev(sch);
+       if (cdev) {
+               rc = sysfs_create_group(&sch->dev.kobj,
+                                       &io_subchannel_attr_group);
+               if (rc)
+                       CIO_MSG_EVENT(0, "Failed to create io subchannel "
+                                     "attributes for subchannel "
+                                     "0.%x.%04x (rc=%d)\n",
+                                     sch->schid.ssid, sch->schid.sch_no, rc);
                /*
                 * This subchannel already has an associated ccw_device.
-                * Register it and exit. This happens for all early
-                * device, e.g. the console.
+                * Throw the delayed uevent for the subchannel, register
+                * the ccw_device and exit. This happens for all early
+                * devices, e.g. the console.
                 */
-               cdev = sch->dev.driver_data;
+               sch->dev.uevent_suppress = 0;
+               kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
+               cdev->dev.groups = ccwdev_attr_groups;
                device_initialize(&cdev->dev);
                ccw_device_register(cdev);
-               subchannel_add_files(&sch->dev);
                /*
                 * Check if the device is already online. If it is
                 * the reference count needs to be corrected
@@ -845,123 +1178,198 @@ io_subchannel_probe (struct subchannel *sch)
                        get_device(&cdev->dev);
                return 0;
        }
-       cdev = kzalloc (sizeof(*cdev), GFP_KERNEL);
+       io_subchannel_init_fields(sch);
+       rc = sysfs_create_group(&sch->dev.kobj,
+                               &io_subchannel_attr_group);
+       if (rc)
+               return rc;
+       /* Allocate I/O subchannel private data. */
+       sch->private = kzalloc(sizeof(struct io_subchannel_private),
+                              GFP_KERNEL | GFP_DMA);
+       if (!sch->private) {
+               rc = -ENOMEM;
+               goto out_err;
+       }
+       /*
+        * First check if a fitting device may be found amongst the
+        * disconnected devices or in the orphanage.
+        */
+       dev_id.devno = sch->schib.pmcw.dev;
+       dev_id.ssid = sch->schid.ssid;
+       cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
        if (!cdev)
-               return -ENOMEM;
-       cdev->private = kzalloc(sizeof(struct ccw_device_private),
-                               GFP_KERNEL | GFP_DMA);
-       if (!cdev->private) {
-               kfree(cdev);
-               return -ENOMEM;
+               cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
+                                                    &dev_id);
+       if (cdev) {
+               /*
+                * Schedule moving the device until when we have a registered
+                * subchannel to move to and succeed the probe. We can
+                * unregister later again, when the probe is through.
+                */
+               cdev->private->sch = sch;
+               PREPARE_WORK(&cdev->private->kick_work,
+                            ccw_device_move_to_sch);
+               queue_work(slow_path_wq, &cdev->private->kick_work);
+               return 0;
        }
-       atomic_set(&cdev->private->onoff, 0);
-       cdev->dev.parent = &sch->dev;
-       cdev->dev.release = ccw_device_release;
-       INIT_LIST_HEAD(&cdev->private->kick_work.entry);
-       /* Do first half of device_register. */
-       device_initialize(&cdev->dev);
-
-       if (!get_device(&sch->dev)) {
-               if (cdev->dev.release)
-                       cdev->dev.release(&cdev->dev);
-               return -ENODEV;
+       cdev = io_subchannel_create_ccwdev(sch);
+       if (IS_ERR(cdev)) {
+               rc = PTR_ERR(cdev);
+               goto out_err;
        }
-
        rc = io_subchannel_recog(cdev, sch);
        if (rc) {
-               spin_lock_irqsave(&sch->lock, flags);
-               sch->dev.driver_data = NULL;
-               spin_unlock_irqrestore(&sch->lock, flags);
+               spin_lock_irqsave(sch->lock, flags);
+               sch_set_cdev(sch, NULL);
+               spin_unlock_irqrestore(sch->lock, flags);
                if (cdev->dev.release)
                        cdev->dev.release(&cdev->dev);
+               goto out_err;
        }
-
+       return 0;
+out_err:
+       kfree(sch->private);
+       sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
        return rc;
 }
 
-static void
-ccw_device_unregister(void *data)
-{
-       struct ccw_device *cdev;
-
-       cdev = (struct ccw_device *)data;
-       if (test_and_clear_bit(1, &cdev->private->registered))
-               device_unregister(&cdev->dev);
-       put_device(&cdev->dev);
-}
-
 static int
 io_subchannel_remove (struct subchannel *sch)
 {
        struct ccw_device *cdev;
        unsigned long flags;
 
-       if (!sch->dev.driver_data)
+       cdev = sch_get_cdev(sch);
+       if (!cdev)
                return 0;
-       cdev = sch->dev.driver_data;
        /* Set ccw device to not operational and drop reference. */
        spin_lock_irqsave(cdev->ccwlock, flags);
-       sch->dev.driver_data = NULL;
+       sch_set_cdev(sch, NULL);
        cdev->private->state = DEV_STATE_NOT_OPER;
        spin_unlock_irqrestore(cdev->ccwlock, flags);
-       /*
-        * Put unregistration on workqueue to avoid livelocks on the css bus
-        * semaphore.
-        */
-       if (get_device(&cdev->dev)) {
-               PREPARE_WORK(&cdev->private->kick_work,
-                            ccw_device_unregister, cdev);
-               queue_work(ccw_device_work, &cdev->private->kick_work);
-       }
+       ccw_device_unregister(cdev);
+       put_device(&cdev->dev);
+       kfree(sch->private);
+       sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
        return 0;
 }
 
-static int
-io_subchannel_notify(struct device *dev, int event)
+static int io_subchannel_notify(struct subchannel *sch, int event)
 {
        struct ccw_device *cdev;
 
-       cdev = dev->driver_data;
+       cdev = sch_get_cdev(sch);
        if (!cdev)
                return 0;
-       if (!cdev->drv)
-               return 0;
-       if (!cdev->online)
-               return 0;
-       return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
+       return ccw_device_notify(cdev, event);
 }
 
-static void
-io_subchannel_verify(struct device *dev)
+static void io_subchannel_verify(struct subchannel *sch)
 {
        struct ccw_device *cdev;
 
-       cdev = dev->driver_data;
+       cdev = sch_get_cdev(sch);
        if (cdev)
                dev_fsm_event(cdev, DEV_EVENT_VERIFY);
 }
 
-static void
-io_subchannel_ioterm(struct device *dev)
+static int check_for_io_on_path(struct subchannel *sch, int mask)
 {
-       struct ccw_device *cdev;
+       int cc;
 
-       cdev = dev->driver_data;
-       if (!cdev)
+       cc = stsch(sch->schid, &sch->schib);
+       if (cc)
+               return 0;
+       if (scsw_actl(&sch->schib.scsw) && sch->schib.pmcw.lpum == mask)
+               return 1;
+       return 0;
+}
+
+static void terminate_internal_io(struct subchannel *sch,
+                                 struct ccw_device *cdev)
+{
+       if (cio_clear(sch)) {
+               /* Recheck device in case clear failed. */
+               sch->lpm = 0;
+               if (cdev->online)
+                       dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+               else
+                       css_schedule_eval(sch->schid);
                return;
+       }
        cdev->private->state = DEV_STATE_CLEAR_VERIFY;
+       /* Request retry of internal operation. */
+       cdev->private->flags.intretry = 1;
+       /* Call handler. */
        if (cdev->handler)
                cdev->handler(cdev, cdev->private->intparm,
                              ERR_PTR(-EIO));
 }
 
+static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
+{
+       struct ccw_device *cdev;
+
+       cdev = sch_get_cdev(sch);
+       if (!cdev)
+               return;
+       if (check_for_io_on_path(sch, mask)) {
+               if (cdev->private->state == DEV_STATE_ONLINE)
+                       ccw_device_kill_io(cdev);
+               else {
+                       terminate_internal_io(sch, cdev);
+                       /* Re-start path verification. */
+                       dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+               }
+       } else
+               /* trigger path verification. */
+               dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+
+}
+
+static int io_subchannel_chp_event(struct subchannel *sch,
+                                  struct chp_link *link, int event)
+{
+       int mask;
+
+       mask = chp_ssd_get_mask(&sch->ssd_info, link);
+       if (!mask)
+               return 0;
+       switch (event) {
+       case CHP_VARY_OFF:
+               sch->opm &= ~mask;
+               sch->lpm &= ~mask;
+               io_subchannel_terminate_path(sch, mask);
+               break;
+       case CHP_VARY_ON:
+               sch->opm |= mask;
+               sch->lpm |= mask;
+               io_subchannel_verify(sch);
+               break;
+       case CHP_OFFLINE:
+               if (stsch(sch->schid, &sch->schib))
+                       return -ENXIO;
+               if (!css_sch_is_valid(&sch->schib))
+                       return -ENODEV;
+               io_subchannel_terminate_path(sch, mask);
+               break;
+       case CHP_ONLINE:
+               if (stsch(sch->schid, &sch->schib))
+                       return -ENXIO;
+               sch->lpm |= mask & sch->opm;
+               io_subchannel_verify(sch);
+               break;
+       }
+       return 0;
+}
+
 static void
 io_subchannel_shutdown(struct subchannel *sch)
 {
        struct ccw_device *cdev;
        int ret;
 
-       cdev = sch->dev.driver_data;
+       cdev = sch_get_cdev(sch);
 
        if (cio_is_console(sch->schid))
                return;
@@ -984,16 +1392,267 @@ io_subchannel_shutdown(struct subchannel *sch)
        cio_disable_subchannel(sch);
 }
 
+static int io_subchannel_get_status(struct subchannel *sch)
+{
+       struct schib schib;
+
+       if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
+               return CIO_GONE;
+       if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
+               return CIO_REVALIDATE;
+       if (!sch->lpm)
+               return CIO_NO_PATH;
+       return CIO_OPER;
+}
+
+static int device_is_disconnected(struct ccw_device *cdev)
+{
+       if (!cdev)
+               return 0;
+       return (cdev->private->state == DEV_STATE_DISCONNECTED ||
+               cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
+}
+
+static int recovery_check(struct device *dev, void *data)
+{
+       struct ccw_device *cdev = to_ccwdev(dev);
+       int *redo = data;
+
+       spin_lock_irq(cdev->ccwlock);
+       switch (cdev->private->state) {
+       case DEV_STATE_DISCONNECTED:
+               CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
+                             cdev->private->dev_id.ssid,
+                             cdev->private->dev_id.devno);
+               dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+               *redo = 1;
+               break;
+       case DEV_STATE_DISCONNECTED_SENSE_ID:
+               *redo = 1;
+               break;
+       }
+       spin_unlock_irq(cdev->ccwlock);
+
+       return 0;
+}
+
+static void recovery_work_func(struct work_struct *unused)
+{
+       int redo = 0;
+
+       bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
+       if (redo) {
+               spin_lock_irq(&recovery_lock);
+               if (!timer_pending(&recovery_timer)) {
+                       if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
+                               recovery_phase++;
+                       mod_timer(&recovery_timer, jiffies +
+                                 recovery_delay[recovery_phase] * HZ);
+               }
+               spin_unlock_irq(&recovery_lock);
+       } else
+               CIO_MSG_EVENT(4, "recovery: end\n");
+}
+
+static DECLARE_WORK(recovery_work, recovery_work_func);
+
+static void recovery_func(unsigned long data)
+{
+       /*
+        * We can't do our recovery in softirq context and it's not
+        * performance critical, so we schedule it.
+        */
+       schedule_work(&recovery_work);
+}
+
+static void ccw_device_schedule_recovery(void)
+{
+       unsigned long flags;
+
+       CIO_MSG_EVENT(4, "recovery: schedule\n");
+       spin_lock_irqsave(&recovery_lock, flags);
+       if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
+               recovery_phase = 0;
+               mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
+       }
+       spin_unlock_irqrestore(&recovery_lock, flags);
+}
+
+static int purge_fn(struct device *dev, void *data)
+{
+       struct ccw_device *cdev = to_ccwdev(dev);
+       struct ccw_device_private *priv = cdev->private;
+       int unreg;
+
+       spin_lock_irq(cdev->ccwlock);
+       unreg = is_blacklisted(priv->dev_id.ssid, priv->dev_id.devno) &&
+               (priv->state == DEV_STATE_OFFLINE);
+       spin_unlock_irq(cdev->ccwlock);
+       if (!unreg)
+               goto out;
+       if (!get_device(&cdev->dev))
+               goto out;
+       CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", priv->dev_id.ssid,
+                     priv->dev_id.devno);
+       PREPARE_WORK(&cdev->private->kick_work, ccw_device_call_sch_unregister);
+       queue_work(slow_path_wq, &cdev->private->kick_work);
+
+out:
+       /* Abort loop in case of pending signal. */
+       if (signal_pending(current))
+               return -EINTR;
+
+       return 0;
+}
+
+/**
+ * ccw_purge_blacklisted - purge unused, blacklisted devices
+ *
+ * Unregister all ccw devices that are offline and on the blacklist.
+ */
+int ccw_purge_blacklisted(void)
+{
+       CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
+       bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
+       return 0;
+}
+
+static void device_set_disconnected(struct ccw_device *cdev)
+{
+       if (!cdev)
+               return;
+       ccw_device_set_timeout(cdev, 0);
+       cdev->private->flags.fake_irb = 0;
+       cdev->private->state = DEV_STATE_DISCONNECTED;
+       if (cdev->online)
+               ccw_device_schedule_recovery();
+}
+
+void ccw_device_set_notoper(struct ccw_device *cdev)
+{
+       struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+       CIO_TRACE_EVENT(2, "notoper");
+       CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+       ccw_device_set_timeout(cdev, 0);
+       cio_disable_subchannel(sch);
+       cdev->private->state = DEV_STATE_NOT_OPER;
+}
+
+static int io_subchannel_sch_event(struct subchannel *sch, int slow)
+{
+       int event, ret, disc;
+       unsigned long flags;
+       enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE, DISC } action;
+       struct ccw_device *cdev;
+
+       spin_lock_irqsave(sch->lock, flags);
+       cdev = sch_get_cdev(sch);
+       disc = device_is_disconnected(cdev);
+       if (disc && slow) {
+               /* Disconnected devices are evaluated directly only.*/
+               spin_unlock_irqrestore(sch->lock, flags);
+               return 0;
+       }
+       /* No interrupt after machine check - kill pending timers. */
+       if (cdev)
+               ccw_device_set_timeout(cdev, 0);
+       if (!disc && !slow) {
+               /* Non-disconnected devices are evaluated on the slow path. */
+               spin_unlock_irqrestore(sch->lock, flags);
+               return -EAGAIN;
+       }
+       event = io_subchannel_get_status(sch);
+       CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
+                     sch->schid.ssid, sch->schid.sch_no, event,
+                     disc ? "disconnected" : "normal",
+                     slow ? "slow" : "fast");
+       /* Analyze subchannel status. */
+       action = NONE;
+       switch (event) {
+       case CIO_NO_PATH:
+               if (disc) {
+                       /* Check if paths have become available. */
+                       action = REPROBE;
+                       break;
+               }
+               /* fall through */
+       case CIO_GONE:
+               /* Ask driver what to do with device. */
+               if (io_subchannel_notify(sch, event))
+                       action = DISC;
+               else
+                       action = UNREGISTER;
+               break;
+       case CIO_REVALIDATE:
+               /* Device will be removed, so no notify necessary. */
+               if (disc)
+                       /* Reprobe because immediate unregister might block. */
+                       action = REPROBE;
+               else
+                       action = UNREGISTER_PROBE;
+               break;
+       case CIO_OPER:
+               if (disc)
+                       /* Get device operational again. */
+                       action = REPROBE;
+               break;
+       }
+       /* Perform action. */
+       ret = 0;
+       switch (action) {
+       case UNREGISTER:
+       case UNREGISTER_PROBE:
+               ccw_device_set_notoper(cdev);
+               /* Unregister device (will use subchannel lock). */
+               spin_unlock_irqrestore(sch->lock, flags);
+               css_sch_device_unregister(sch);
+               spin_lock_irqsave(sch->lock, flags);
+
+               /* Reset intparm to zeroes. */
+               sch->schib.pmcw.intparm = 0;
+               cio_modify(sch);
+               break;
+       case REPROBE:
+               ccw_device_trigger_reprobe(cdev);
+               break;
+       case DISC:
+               device_set_disconnected(cdev);
+               break;
+       default:
+               break;
+       }
+       spin_unlock_irqrestore(sch->lock, flags);
+       /* Probe if necessary. */
+       if (action == UNREGISTER_PROBE)
+               ret = css_probe_device(sch->schid);
+
+       return ret;
+}
+
 #ifdef CONFIG_CCW_CONSOLE
 static struct ccw_device console_cdev;
+static char console_cdev_name[10] = "0.x.xxxx";
 static struct ccw_device_private console_private;
 static int console_cdev_in_use;
 
-static int
-ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
+static DEFINE_SPINLOCK(ccw_console_lock);
+
+spinlock_t * cio_get_console_lock(void)
+{
+       return &ccw_console_lock;
+}
+
+static int ccw_device_console_enable(struct ccw_device *cdev,
+                                    struct subchannel *sch)
 {
        int rc;
 
+       /* Attach subchannel private data. */
+       sch->private = cio_get_console_priv();
+       memset(sch->private, 0, sizeof(struct io_subchannel_private));
+       io_subchannel_init_fields(sch);
+       sch->driver = &io_subchannel_driver;
        /* Initialize the ccw_device structure. */
        cdev->dev.parent= &sch->dev;
        rc = io_subchannel_recog(cdev, sch);
@@ -1034,6 +1693,7 @@ ccw_device_probe_console(void)
        memset(&console_cdev, 0, sizeof(struct ccw_device));
        memset(&console_private, 0, sizeof(struct ccw_device_private));
        console_cdev.private = &console_private;
+       console_private.cdev = &console_cdev;
        ret = ccw_device_console_enable(&console_cdev, sch);
        if (ret) {
                cio_release_console();
@@ -1043,6 +1703,14 @@ ccw_device_probe_console(void)
        console_cdev.online = 1;
        return &console_cdev;
 }
+
+
+const char *cio_get_console_cdev_name(struct subchannel *sch)
+{
+       snprintf(console_cdev_name, 10, "0.%x.%04x",
+                sch->schid.ssid, sch->schib.pmcw.dev);
+       return (const char *)console_cdev_name;
+}
 #endif
 
 /*
@@ -1055,12 +1723,23 @@ __ccwdev_check_busid(struct device *dev, void *id)
 
        bus_id = id;
 
-       return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
+       return (strcmp(bus_id, dev_name(dev)) == 0);
 }
 
 
-struct ccw_device *
-get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
+/**
+ * get_ccwdev_by_busid() - obtain device from a bus id
+ * @cdrv: driver the device is owned by
+ * @bus_id: bus id of the device to be searched
+ *
+ * This function searches all devices owned by @cdrv for a device with a bus
+ * id matching @bus_id.
+ * Returns:
+ *  If a match is found, its reference count of the found device is increased
+ *  and it is returned; else %NULL is returned.
+ */
+struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
+                                      const char *bus_id)
 {
        struct device *dev;
        struct device_driver *drv;
@@ -1112,7 +1791,6 @@ ccw_device_remove (struct device *dev)
        struct ccw_driver *cdrv = cdev->drv;
        int ret;
 
-       pr_debug("removing device %s\n", cdev->dev.bus_id);
        if (cdrv->remove)
                cdrv->remove(cdev);
        if (cdev->online) {
@@ -1124,36 +1802,61 @@ ccw_device_remove (struct device *dev)
                        wait_event(cdev->private->wait_q,
                                   dev_fsm_final_state(cdev));
                else
-                       //FIXME: we can't fail!
-                       pr_debug("ccw_device_offline returned %d, device %s\n",
-                                ret, cdev->dev.bus_id);
+                       CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
+                                     "device 0.%x.%04x\n",
+                                     ret, cdev->private->dev_id.ssid,
+                                     cdev->private->dev_id.devno);
        }
        ccw_device_set_timeout(cdev, 0);
        cdev->drv = NULL;
        return 0;
 }
 
+static void ccw_device_shutdown(struct device *dev)
+{
+       struct ccw_device *cdev;
+
+       cdev = to_ccwdev(dev);
+       if (cdev->drv && cdev->drv->shutdown)
+               cdev->drv->shutdown(cdev);
+       disable_cmf(cdev);
+}
+
 struct bus_type ccw_bus_type = {
        .name   = "ccw",
        .match  = ccw_bus_match,
        .uevent = ccw_uevent,
        .probe  = ccw_device_probe,
        .remove = ccw_device_remove,
+       .shutdown = ccw_device_shutdown,
 };
 
-int
-ccw_driver_register (struct ccw_driver *cdriver)
+/**
+ * ccw_driver_register() - register a ccw driver
+ * @cdriver: driver to be registered
+ *
+ * This function is mainly a wrapper around driver_register().
+ * Returns:
+ *   %0 on success and a negative error value on failure.
+ */
+int ccw_driver_register(struct ccw_driver *cdriver)
 {
        struct device_driver *drv = &cdriver->driver;
 
        drv->bus = &ccw_bus_type;
        drv->name = cdriver->name;
+       drv->owner = cdriver->owner;
 
        return driver_register(drv);
 }
 
-void
-ccw_driver_unregister (struct ccw_driver *cdriver)
+/**
+ * ccw_driver_unregister() - deregister a ccw driver
+ * @cdriver: driver to be deregistered
+ *
+ * This function is mainly a wrapper around driver_unregister().
+ */
+void ccw_driver_unregister(struct ccw_driver *cdriver)
 {
        driver_unregister(&cdriver->driver);
 }
@@ -1176,5 +1879,4 @@ EXPORT_SYMBOL(ccw_driver_unregister);
 EXPORT_SYMBOL(get_ccwdev_by_busid);
 EXPORT_SYMBOL(ccw_bus_type);
 EXPORT_SYMBOL(ccw_device_work);
-EXPORT_SYMBOL(ccw_device_notify_work);
 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);