Merge branch 'for-rmk/samsung6' of git://git.fluff.org/bjdooks/linux into devel-stable
[linux-2.6.git] / drivers / s390 / block / dasd.c
index 6527ff6..5905936 100644 (file)
@@ -5,12 +5,12 @@
  *                 Carsten Otte <Cotte@de.ibm.com>
  *                 Martin Schwidefsky <schwidefsky@de.ibm.com>
  * Bugreports.to..: <Linux390@de.ibm.com>
- * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
- *
- * $Revision: 1.164 $
+ * Copyright IBM Corp. 1999, 2009
  */
 
-#include <linux/config.h>
+#define KMSG_COMPONENT "dasd"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
 #include <linux/kmod.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/major.h>
 #include <linux/slab.h>
 #include <linux/buffer_head.h>
+#include <linux/hdreg.h>
+#include <linux/async.h>
 
 #include <asm/ccwdev.h>
 #include <asm/ebcdic.h>
 #include <asm/idals.h>
-#include <asm/todclk.h>
+#include <asm/itcw.h>
 
 /* This is ugly... */
 #define PRINTK_HEADER "dasd:"
  */
 debug_info_t *dasd_debug_area;
 struct dasd_discipline *dasd_diag_discipline_pointer;
+void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
 
 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
                   " Copyright 2000 IBM Corporation");
 MODULE_SUPPORTED_DEVICE("dasd");
-MODULE_PARM(dasd, "1-" __MODULE_STRING(256) "s");
 MODULE_LICENSE("GPL");
 
 /*
  * SECTION: prototypes for static functions of dasd.c
  */
-static int  dasd_alloc_queue(struct dasd_device * device);
-static void dasd_setup_queue(struct dasd_device * device);
-static void dasd_free_queue(struct dasd_device * device);
-static void dasd_flush_request_queue(struct dasd_device *);
-static void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
-static void dasd_flush_ccw_queue(struct dasd_device *, int);
-static void dasd_tasklet(struct dasd_device *);
-static void do_kick_device(void *data);
+static int  dasd_alloc_queue(struct dasd_block *);
+static void dasd_setup_queue(struct dasd_block *);
+static void dasd_free_queue(struct dasd_block *);
+static void dasd_flush_request_queue(struct dasd_block *);
+static int dasd_flush_block_queue(struct dasd_block *);
+static void dasd_device_tasklet(struct dasd_device *);
+static void dasd_block_tasklet(struct dasd_block *);
+static void do_kick_device(struct work_struct *);
+static void do_restore_device(struct work_struct *);
+static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
+static void dasd_device_timeout(unsigned long);
+static void dasd_block_timeout(unsigned long);
+static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
 
 /*
  * SECTION: Operations on the device structure.
  */
 static wait_queue_head_t dasd_init_waitq;
+static wait_queue_head_t dasd_flush_wq;
+static wait_queue_head_t generic_waitq;
 
 /*
  * Allocate memory for a new device structure.
  */
-struct dasd_device *
-dasd_alloc_device(void)
+struct dasd_device *dasd_alloc_device(void)
 {
        struct dasd_device *device;
 
-       device = kmalloc(sizeof (struct dasd_device), GFP_ATOMIC);
-       if (device == NULL)
+       device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
+       if (!device)
                return ERR_PTR(-ENOMEM);
-       memset(device, 0, sizeof (struct dasd_device));
-       /* open_count = 0 means device online but not in use */
-       atomic_set(&device->open_count, -1);
 
        /* Get two pages for normal block device operations. */
        device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
-       if (device->ccw_mem == NULL) {
+       if (!device->ccw_mem) {
                kfree(device);
                return ERR_PTR(-ENOMEM);
        }
        /* Get one page for error recovery. */
        device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
-       if (device->erp_mem == NULL) {
+       if (!device->erp_mem) {
                free_pages((unsigned long) device->ccw_mem, 1);
                kfree(device);
                return ERR_PTR(-ENOMEM);
@@ -95,14 +100,16 @@ dasd_alloc_device(void)
        dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
        dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
        spin_lock_init(&device->mem_lock);
-       spin_lock_init(&device->request_queue_lock);
-       atomic_set (&device->tasklet_scheduled, 0);
-       tasklet_init(&device->tasklet, 
-                    (void (*)(unsigned long)) dasd_tasklet,
+       atomic_set(&device->tasklet_scheduled, 0);
+       tasklet_init(&device->tasklet,
+                    (void (*)(unsigned long)) dasd_device_tasklet,
                     (unsigned long) device);
        INIT_LIST_HEAD(&device->ccw_queue);
        init_timer(&device->timer);
-       INIT_WORK(&device->kick_work, do_kick_device, device);
+       device->timer.function = dasd_device_timeout;
+       device->timer.data = (unsigned long) device;
+       INIT_WORK(&device->kick_work, do_kick_device);
+       INIT_WORK(&device->restore_device, do_restore_device);
        device->state = DASD_STATE_NEW;
        device->target = DASD_STATE_NEW;
 
@@ -112,36 +119,69 @@ dasd_alloc_device(void)
 /*
  * Free memory of a device structure.
  */
-void
-dasd_free_device(struct dasd_device *device)
+void dasd_free_device(struct dasd_device *device)
 {
-       if (device->private)
-               kfree(device->private);
+       kfree(device->private);
        free_page((unsigned long) device->erp_mem);
        free_pages((unsigned long) device->ccw_mem, 1);
        kfree(device);
 }
 
 /*
+ * Allocate memory for a new device structure.
+ */
+struct dasd_block *dasd_alloc_block(void)
+{
+       struct dasd_block *block;
+
+       block = kzalloc(sizeof(*block), GFP_ATOMIC);
+       if (!block)
+               return ERR_PTR(-ENOMEM);
+       /* open_count = 0 means device online but not in use */
+       atomic_set(&block->open_count, -1);
+
+       spin_lock_init(&block->request_queue_lock);
+       atomic_set(&block->tasklet_scheduled, 0);
+       tasklet_init(&block->tasklet,
+                    (void (*)(unsigned long)) dasd_block_tasklet,
+                    (unsigned long) block);
+       INIT_LIST_HEAD(&block->ccw_queue);
+       spin_lock_init(&block->queue_lock);
+       init_timer(&block->timer);
+       block->timer.function = dasd_block_timeout;
+       block->timer.data = (unsigned long) block;
+
+       return block;
+}
+
+/*
+ * Free memory of a device structure.
+ */
+void dasd_free_block(struct dasd_block *block)
+{
+       kfree(block);
+}
+
+/*
  * Make a new device known to the system.
  */
-static inline int
-dasd_state_new_to_known(struct dasd_device *device)
+static int dasd_state_new_to_known(struct dasd_device *device)
 {
        int rc;
 
        /*
-        * As long as the device is not in state DASD_STATE_NEW we want to 
+        * As long as the device is not in state DASD_STATE_NEW we want to
         * keep the reference count > 0.
         */
        dasd_get_device(device);
 
-       rc = dasd_alloc_queue(device);
-       if (rc) {
-               dasd_put_device(device);
-               return rc;
+       if (device->block) {
+               rc = dasd_alloc_queue(device->block);
+               if (rc) {
+                       dasd_put_device(device);
+                       return rc;
+               }
        }
-
        device->state = DASD_STATE_KNOWN;
        return 0;
 }
@@ -149,37 +189,48 @@ dasd_state_new_to_known(struct dasd_device *device)
 /*
  * Let the system forget about a device.
  */
-static inline void
-dasd_state_known_to_new(struct dasd_device * device)
+static int dasd_state_known_to_new(struct dasd_device *device)
 {
+       /* Disable extended error reporting for this device. */
+       dasd_eer_disable(device);
        /* Forget the discipline information. */
+       if (device->discipline) {
+               if (device->discipline->uncheck_device)
+                       device->discipline->uncheck_device(device);
+               module_put(device->discipline->owner);
+       }
        device->discipline = NULL;
+       if (device->base_discipline)
+               module_put(device->base_discipline->owner);
+       device->base_discipline = NULL;
        device->state = DASD_STATE_NEW;
 
-       dasd_free_queue(device);
+       if (device->block)
+               dasd_free_queue(device->block);
 
        /* Give up reference we took in dasd_state_new_to_known. */
        dasd_put_device(device);
+       return 0;
 }
 
 /*
  * Request the irq line for the device.
  */
-static inline int
-dasd_state_known_to_basic(struct dasd_device * device)
+static int dasd_state_known_to_basic(struct dasd_device *device)
 {
        int rc;
 
        /* Allocate and register gendisk structure. */
-       rc = dasd_gendisk_alloc(device);
-       if (rc)
-               return rc;
-
+       if (device->block) {
+               rc = dasd_gendisk_alloc(device->block);
+               if (rc)
+                       return rc;
+       }
        /* register 'device' debug area, used for all DBF_DEV_XXX calls */
-       device->debug_area = debug_register(device->cdev->dev.bus_id, 1, 2,
-                                           8 * sizeof (long));
+       device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
+                                           8 * sizeof(long));
        debug_register_view(device->debug_area, &debug_sprintf_view);
-       debug_set_level(device->debug_area, DBF_EMERG);
+       debug_set_level(device->debug_area, DBF_WARNING);
        DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
 
        device->state = DASD_STATE_BASIC;
@@ -189,17 +240,25 @@ dasd_state_known_to_basic(struct dasd_device * device)
 /*
  * Release the irq line for the device. Terminate any running i/o.
  */
-static inline void
-dasd_state_basic_to_known(struct dasd_device * device)
+static int dasd_state_basic_to_known(struct dasd_device *device)
 {
-       dasd_gendisk_free(device);
-       dasd_flush_ccw_queue(device, 1);
+       int rc;
+       if (device->block) {
+               dasd_gendisk_free(device->block);
+               dasd_block_clear_timer(device->block);
+       }
+       rc = dasd_flush_device_queue(device);
+       if (rc)
+               return rc;
+       dasd_device_clear_timer(device);
+
        DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
        if (device->debug_area != NULL) {
                debug_unregister(device->debug_area);
                device->debug_area = NULL;
        }
        device->state = DASD_STATE_KNOWN;
+       return 0;
 }
 
 /*
@@ -211,25 +270,38 @@ dasd_state_basic_to_known(struct dasd_device * device)
  * interrupt for this detection ccw uses the kernel event daemon to
  * trigger the call to dasd_change_state. All this is done in the
  * discipline code, see dasd_eckd.c.
- * After the analysis ccw is done (do_analysis returned 0 or error)
- * the block device is setup. Either a fake disk is added to allow
- * formatting or a proper device request queue is created.
+ * After the analysis ccw is done (do_analysis returned 0) the block
+ * device is setup.
+ * In case the analysis returns an error, the device setup is stopped
+ * (a fake disk was already added to allow formatting).
  */
-static inline int
-dasd_state_basic_to_ready(struct dasd_device * device)
+static int dasd_state_basic_to_ready(struct dasd_device *device)
 {
        int rc;
+       struct dasd_block *block;
 
        rc = 0;
-       if (device->discipline->do_analysis != NULL)
-               rc = device->discipline->do_analysis(device);
-       if (rc)
-               return rc;
-       dasd_setup_queue(device);
-       device->state = DASD_STATE_READY;
-       if (dasd_scan_partitions(device) != 0)
-               device->state = DASD_STATE_BASIC;
-       return 0;
+       block = device->block;
+       /* make disk known with correct capacity */
+       if (block) {
+               if (block->base->discipline->do_analysis != NULL)
+                       rc = block->base->discipline->do_analysis(block);
+               if (rc) {
+                       if (rc != -EAGAIN)
+                               device->state = DASD_STATE_UNFMT;
+                       return rc;
+               }
+               dasd_setup_queue(block);
+               set_capacity(block->gdp,
+                            block->blocks << block->s2b_shift);
+               device->state = DASD_STATE_READY;
+               rc = dasd_scan_partitions(block);
+               if (rc)
+                       device->state = DASD_STATE_BASIC;
+       } else {
+               device->state = DASD_STATE_READY;
+       }
+       return rc;
 }
 
 /*
@@ -237,16 +309,34 @@ dasd_state_basic_to_ready(struct dasd_device * device)
  * Forget format information. Check if the target level is basic
  * and if it is create fake disk for formatting.
  */
-static inline void
-dasd_state_ready_to_basic(struct dasd_device * device)
+static int dasd_state_ready_to_basic(struct dasd_device *device)
+{
+       int rc;
+
+       device->state = DASD_STATE_BASIC;
+       if (device->block) {
+               struct dasd_block *block = device->block;
+               rc = dasd_flush_block_queue(block);
+               if (rc) {
+                       device->state = DASD_STATE_READY;
+                       return rc;
+               }
+               dasd_destroy_partitions(block);
+               dasd_flush_request_queue(block);
+               block->blocks = 0;
+               block->bp_block = 0;
+               block->s2b_shift = 0;
+       }
+       return 0;
+}
+
+/*
+ * Back to basic.
+ */
+static int dasd_state_unfmt_to_basic(struct dasd_device *device)
 {
-       dasd_flush_ccw_queue(device, 0);
-       dasd_destroy_partitions(device);
-       dasd_flush_request_queue(device);
-       device->blocks = 0;
-       device->bp_block = 0;
-       device->s2b_shift = 0;
        device->state = DASD_STATE_BASIC;
+       return 0;
 }
 
 /*
@@ -254,28 +344,61 @@ dasd_state_ready_to_basic(struct dasd_device * device)
  * the requeueing of requests from the linux request queue to the
  * ccw queue.
  */
-static inline int
+static int
 dasd_state_ready_to_online(struct dasd_device * device)
 {
+       int rc;
+       struct gendisk *disk;
+       struct disk_part_iter piter;
+       struct hd_struct *part;
+
+       if (device->discipline->ready_to_online) {
+               rc = device->discipline->ready_to_online(device);
+               if (rc)
+                       return rc;
+       }
        device->state = DASD_STATE_ONLINE;
-       dasd_schedule_bh(device);
+       if (device->block) {
+               dasd_schedule_block_bh(device->block);
+               disk = device->block->bdev->bd_disk;
+               disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+               while ((part = disk_part_iter_next(&piter)))
+                       kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
+               disk_part_iter_exit(&piter);
+       }
        return 0;
 }
 
 /*
  * Stop the requeueing of requests again.
  */
-static inline void
-dasd_state_online_to_ready(struct dasd_device * device)
+static int dasd_state_online_to_ready(struct dasd_device *device)
 {
+       int rc;
+       struct gendisk *disk;
+       struct disk_part_iter piter;
+       struct hd_struct *part;
+
+       if (device->discipline->online_to_ready) {
+               rc = device->discipline->online_to_ready(device);
+               if (rc)
+                       return rc;
+       }
        device->state = DASD_STATE_READY;
+       if (device->block) {
+               disk = device->block->bdev->bd_disk;
+               disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+               while ((part = disk_part_iter_next(&piter)))
+                       kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
+               disk_part_iter_exit(&piter);
+       }
+       return 0;
 }
 
 /*
  * Device startup state changes.
  */
-static inline int
-dasd_increase_state(struct dasd_device *device)
+static int dasd_increase_state(struct dasd_device *device)
 {
        int rc;
 
@@ -295,6 +418,11 @@ dasd_increase_state(struct dasd_device *device)
                rc = dasd_state_basic_to_ready(device);
 
        if (!rc &&
+           device->state == DASD_STATE_UNFMT &&
+           device->target > DASD_STATE_UNFMT)
+               rc = -EPERM;
+
+       if (!rc &&
            device->state == DASD_STATE_READY &&
            device->target >= DASD_STATE_ONLINE)
                rc = dasd_state_ready_to_online(device);
@@ -305,35 +433,44 @@ dasd_increase_state(struct dasd_device *device)
 /*
  * Device shutdown state changes.
  */
-static inline int
-dasd_decrease_state(struct dasd_device *device)
+static int dasd_decrease_state(struct dasd_device *device)
 {
+       int rc;
+
+       rc = 0;
        if (device->state == DASD_STATE_ONLINE &&
            device->target <= DASD_STATE_READY)
-               dasd_state_online_to_ready(device);
-       
-       if (device->state == DASD_STATE_READY &&
+               rc = dasd_state_online_to_ready(device);
+
+       if (!rc &&
+           device->state == DASD_STATE_READY &&
            device->target <= DASD_STATE_BASIC)
-               dasd_state_ready_to_basic(device);
-       
-       if (device->state == DASD_STATE_BASIC && 
+               rc = dasd_state_ready_to_basic(device);
+
+       if (!rc &&
+           device->state == DASD_STATE_UNFMT &&
+           device->target <= DASD_STATE_BASIC)
+               rc = dasd_state_unfmt_to_basic(device);
+
+       if (!rc &&
+           device->state == DASD_STATE_BASIC &&
            device->target <= DASD_STATE_KNOWN)
-               dasd_state_basic_to_known(device);
-       
-       if (device->state == DASD_STATE_KNOWN &&
+               rc = dasd_state_basic_to_known(device);
+
+       if (!rc &&
+           device->state == DASD_STATE_KNOWN &&
            device->target <= DASD_STATE_NEW)
-               dasd_state_known_to_new(device);
+               rc = dasd_state_known_to_new(device);
 
-       return 0;
+       return rc;
 }
 
 /*
  * This is the main startup/shutdown routine.
  */
-static void
-dasd_change_state(struct dasd_device *device)
+static void dasd_change_state(struct dasd_device *device)
 {
-        int rc;
+       int rc;
 
        if (device->state == device->target)
                /* Already where we want to go today... */
@@ -342,11 +479,18 @@ dasd_change_state(struct dasd_device *device)
                rc = dasd_increase_state(device);
        else
                rc = dasd_decrease_state(device);
-        if (rc && rc != -EAGAIN)
-                device->target = device->state;
+       if (rc == -EAGAIN)
+               return;
+       if (rc)
+               device->target = device->state;
 
-       if (device->state == device->target)
+       if (device->state == device->target) {
                wake_up(&dasd_init_waitq);
+               dasd_put_device(device);
+       }
+
+       /* let user-space know that the device status changed */
+       kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
 }
 
 /*
@@ -355,19 +499,15 @@ dasd_change_state(struct dasd_device *device)
  * dasd_kick_device will schedule a call do do_kick_device to the kernel
  * event daemon.
  */
-static void
-do_kick_device(void *data)
+static void do_kick_device(struct work_struct *work)
 {
-       struct dasd_device *device;
-
-       device = (struct dasd_device *) data;
+       struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
        dasd_change_state(device);
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
        dasd_put_device(device);
 }
 
-void
-dasd_kick_device(struct dasd_device *device)
+void dasd_kick_device(struct dasd_device *device)
 {
        dasd_get_device(device);
        /* queue call to dasd_kick_device to the kernel event daemon. */
@@ -375,17 +515,38 @@ dasd_kick_device(struct dasd_device *device)
 }
 
 /*
+ * dasd_restore_device will schedule a call do do_restore_device to the kernel
+ * event daemon.
+ */
+static void do_restore_device(struct work_struct *work)
+{
+       struct dasd_device *device = container_of(work, struct dasd_device,
+                                                 restore_device);
+       device->cdev->drv->restore(device->cdev);
+       dasd_put_device(device);
+}
+
+void dasd_restore_device(struct dasd_device *device)
+{
+       dasd_get_device(device);
+       /* queue call to dasd_restore_device to the kernel event daemon. */
+       schedule_work(&device->restore_device);
+}
+
+/*
  * Set the target state for a device and starts the state change.
  */
-void
-dasd_set_target_state(struct dasd_device *device, int target)
+void dasd_set_target_state(struct dasd_device *device, int target)
 {
+       dasd_get_device(device);
        /* If we are in probeonly mode stop at DASD_STATE_READY. */
        if (dasd_probeonly && target > DASD_STATE_READY)
                target = DASD_STATE_READY;
        if (device->target != target) {
-                if (device->state == target)
+               if (device->state == target) {
                        wake_up(&dasd_init_waitq);
+                       dasd_put_device(device);
+               }
                device->target = target;
        }
        if (device->state != device->target)
@@ -395,14 +556,12 @@ dasd_set_target_state(struct dasd_device *device, int target)
 /*
  * Enable devices with device numbers in [from..to].
  */
-static inline int
-_wait_for_device(struct dasd_device *device)
+static inline int _wait_for_device(struct dasd_device *device)
 {
        return (device->state == device->target);
 }
 
-void
-dasd_enable_device(struct dasd_device *device)
+void dasd_enable_device(struct dasd_device *device)
 {
        dasd_set_target_state(device, DASD_STATE_ONLINE);
        if (device->state <= DASD_STATE_KNOWN)
@@ -423,20 +582,20 @@ unsigned int dasd_profile_level = DASD_PROFILE_OFF;
 /*
  * Increments counter in global and local profiling structures.
  */
-#define dasd_profile_counter(value, counter, device) \
+#define dasd_profile_counter(value, counter, block) \
 { \
        int index; \
        for (index = 0; index < 31 && value >> (2+index); index++); \
        dasd_global_profile.counter[index]++; \
-       device->profile.counter[index]++; \
+       block->profile.counter[index]++; \
 }
 
 /*
  * Add profiling information for cqr before execution.
  */
-static inline void
-dasd_profile_start(struct dasd_device *device, struct dasd_ccw_req * cqr,
-                  struct request *req)
+static void dasd_profile_start(struct dasd_block *block,
+                              struct dasd_ccw_req *cqr,
+                              struct request *req)
 {
        struct list_head *l;
        unsigned int counter;
@@ -446,19 +605,19 @@ dasd_profile_start(struct dasd_device *device, struct dasd_ccw_req * cqr,
 
        /* count the length of the chanq for statistics */
        counter = 0;
-       list_for_each(l, &device->ccw_queue)
+       list_for_each(l, &block->ccw_queue)
                if (++counter >= 31)
                        break;
        dasd_global_profile.dasd_io_nr_req[counter]++;
-       device->profile.dasd_io_nr_req[counter]++;
+       block->profile.dasd_io_nr_req[counter]++;
 }
 
 /*
  * Add profiling information for cqr after execution.
  */
-static inline void
-dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
-                struct request *req)
+static void dasd_profile_end(struct dasd_block *block,
+                            struct dasd_ccw_req *cqr,
+                            struct request *req)
 {
        long strtime, irqtime, endtime, tottime;        /* in microseconds */
        long tottimeps, sectors;
@@ -466,7 +625,7 @@ dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
        if (dasd_profile_level != DASD_PROFILE_ON)
                return;
 
-       sectors = req->nr_sectors;
+       sectors = blk_rq_sectors(req);
        if (!cqr->buildclk || !cqr->startclk ||
            !cqr->stopclk || !cqr->endclk ||
            !sectors)
@@ -480,27 +639,27 @@ dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
 
        if (!dasd_global_profile.dasd_io_reqs)
                memset(&dasd_global_profile, 0,
-                      sizeof (struct dasd_profile_info_t));
+                      sizeof(struct dasd_profile_info_t));
        dasd_global_profile.dasd_io_reqs++;
        dasd_global_profile.dasd_io_sects += sectors;
 
-       if (!device->profile.dasd_io_reqs)
-               memset(&device->profile, 0,
-                      sizeof (struct dasd_profile_info_t));
-       device->profile.dasd_io_reqs++;
-       device->profile.dasd_io_sects += sectors;
+       if (!block->profile.dasd_io_reqs)
+               memset(&block->profile, 0,
+                      sizeof(struct dasd_profile_info_t));
+       block->profile.dasd_io_reqs++;
+       block->profile.dasd_io_sects += sectors;
 
-       dasd_profile_counter(sectors, dasd_io_secs, device);
-       dasd_profile_counter(tottime, dasd_io_times, device);
-       dasd_profile_counter(tottimeps, dasd_io_timps, device);
-       dasd_profile_counter(strtime, dasd_io_time1, device);
-       dasd_profile_counter(irqtime, dasd_io_time2, device);
-       dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, device);
-       dasd_profile_counter(endtime, dasd_io_time3, device);
+       dasd_profile_counter(sectors, dasd_io_secs, block);
+       dasd_profile_counter(tottime, dasd_io_times, block);
+       dasd_profile_counter(tottimeps, dasd_io_timps, block);
+       dasd_profile_counter(strtime, dasd_io_time1, block);
+       dasd_profile_counter(irqtime, dasd_io_time2, block);
+       dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, block);
+       dasd_profile_counter(endtime, dasd_io_time3, block);
 }
 #else
-#define dasd_profile_start(device, cqr, req) do {} while (0)
-#define dasd_profile_end(device, cqr, req) do {} while (0)
+#define dasd_profile_start(block, cqr, req) do {} while (0)
+#define dasd_profile_end(block, cqr, req) do {} while (0)
 #endif                         /* CONFIG_DASD_PROFILE */
 
 /*
@@ -510,52 +669,46 @@ dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
  * memory and 2) dasd_smalloc_request uses the static ccw memory
  * that gets allocated for each device.
  */
-struct dasd_ccw_req *
-dasd_kmalloc_request(char *magic, int cplength, int datasize,
-                  struct dasd_device * device)
+struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
+                                         int datasize,
+                                         struct dasd_device *device)
 {
        struct dasd_ccw_req *cqr;
 
        /* Sanity checks */
-       if ( magic == NULL || datasize > PAGE_SIZE ||
-            (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
-               BUG();
+       BUG_ON(datasize > PAGE_SIZE ||
+            (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
 
-       cqr = kmalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
+       cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
        if (cqr == NULL)
                return ERR_PTR(-ENOMEM);
-       memset(cqr, 0, sizeof(struct dasd_ccw_req));
        cqr->cpaddr = NULL;
        if (cplength > 0) {
-               cqr->cpaddr = kmalloc(cplength*sizeof(struct ccw1),
+               cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
                                      GFP_ATOMIC | GFP_DMA);
                if (cqr->cpaddr == NULL) {
                        kfree(cqr);
                        return ERR_PTR(-ENOMEM);
                }
-               memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
        }
        cqr->data = NULL;
        if (datasize > 0) {
-               cqr->data = kmalloc(datasize, GFP_ATOMIC | GFP_DMA);
+               cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
                if (cqr->data == NULL) {
-                       if (cqr->cpaddr != NULL)
-                               kfree(cqr->cpaddr);
+                       kfree(cqr->cpaddr);
                        kfree(cqr);
                        return ERR_PTR(-ENOMEM);
                }
-               memset(cqr->data, 0, datasize);
        }
-       strncpy((char *) &cqr->magic, magic, 4);
-       ASCEBC((char *) &cqr->magic, 4);
+       cqr->magic =  magic;
        set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
        dasd_get_device(device);
        return cqr;
 }
 
-struct dasd_ccw_req *
-dasd_smalloc_request(char *magic, int cplength, int datasize,
-                  struct dasd_device * device)
+struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
+                                         int datasize,
+                                         struct dasd_device *device)
 {
        unsigned long flags;
        struct dasd_ccw_req *cqr;
@@ -563,9 +716,8 @@ dasd_smalloc_request(char *magic, int cplength, int datasize,
        int size;
 
        /* Sanity checks */
-       if ( magic == NULL || datasize > PAGE_SIZE ||
-            (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
-               BUG();
+       BUG_ON(datasize > PAGE_SIZE ||
+            (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
 
        size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
        if (cplength > 0)
@@ -591,8 +743,7 @@ dasd_smalloc_request(char *magic, int cplength, int datasize,
                cqr->data = data;
                memset(cqr->data, 0, datasize);
        }
-       strncpy((char *) &cqr->magic, magic, 4);
-       ASCEBC((char *) &cqr->magic, 4);
+       cqr->magic = magic;
        set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
        dasd_get_device(device);
        return cqr;
@@ -603,10 +754,9 @@ dasd_smalloc_request(char *magic, int cplength, int datasize,
  * idal lists that might have been created by dasd_set_cda and the
  * struct dasd_ccw_req itself.
  */
-void
-dasd_kfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
+void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
 {
-#ifdef CONFIG_ARCH_S390X
+#ifdef CONFIG_64BIT
        struct ccw1 *ccw;
 
        /* Clear any idals used for the request. */
@@ -615,16 +765,13 @@ dasd_kfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
                clear_normalized_cda(ccw);
        } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
 #endif
-       if (cqr->cpaddr != NULL)
-               kfree(cqr->cpaddr);
-       if (cqr->data != NULL)
-               kfree(cqr->data);
+       kfree(cqr->cpaddr);
+       kfree(cqr->data);
        kfree(cqr);
        dasd_put_device(device);
 }
 
-void
-dasd_sfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
+void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
 {
        unsigned long flags;
 
@@ -637,16 +784,15 @@ dasd_sfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
 /*
  * Check discipline magic in cqr.
  */
-static inline int
-dasd_check_cqr(struct dasd_ccw_req *cqr)
+static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
 
        if (cqr == NULL)
                return -EINVAL;
-       device = cqr->device;
+       device = cqr->startdev;
        if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
-               DEV_MESSAGE(KERN_WARNING, device,
+               DBF_DEV_EVENT(DBF_WARNING, device,
                            " dasd_ccw_req 0x%08x magic doesn't match"
                            " discipline 0x%08x",
                            cqr->magic,
@@ -662,28 +808,26 @@ dasd_check_cqr(struct dasd_ccw_req *cqr)
  * ccw_device_clear can fail if the i/o subsystem
  * is in a bad mood.
  */
-int
-dasd_term_IO(struct dasd_ccw_req * cqr)
+int dasd_term_IO(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
        int retries, rc;
+       char errorstring[ERRORLENGTH];
 
        /* Check the cqr */
        rc = dasd_check_cqr(cqr);
        if (rc)
                return rc;
        retries = 0;
-       device = (struct dasd_device *) cqr->device;
+       device = (struct dasd_device *) cqr->startdev;
        while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
                rc = ccw_device_clear(device->cdev, (long) cqr);
                switch (rc) {
                case 0: /* termination successful */
-                       if (cqr->retries > 0) {
-                               cqr->retries--;
-                               cqr->status = DASD_CQR_CLEAR;
-                       } else
-                               cqr->status = DASD_CQR_FAILED;
+                       cqr->retries--;
+                       cqr->status = DASD_CQR_CLEAR_PENDING;
                        cqr->stopclk = get_clock();
+                       cqr->starttime = 0;
                        DBF_DEV_EVENT(DBF_DEBUG, device,
                                      "terminate cqr %p successful",
                                      cqr);
@@ -702,16 +846,16 @@ dasd_term_IO(struct dasd_ccw_req * cqr)
                                      "device busy, retry later");
                        break;
                default:
-                       DEV_MESSAGE(KERN_ERR, device,
-                                   "line %d unknown RC=%d, please "
-                                   "report to linux390@de.ibm.com",
-                                   __LINE__, rc);
+                       /* internal error 10 - unknown rc*/
+                       snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
+                       dev_err(&device->cdev->dev, "An error occurred in the "
+                               "DASD device driver, reason=%s\n", errorstring);
                        BUG();
                        break;
                }
                retries++;
        }
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
        return rc;
 }
 
@@ -719,42 +863,47 @@ dasd_term_IO(struct dasd_ccw_req * cqr)
  * Start the i/o. This start_IO can fail if the channel is really busy.
  * In that case set up a timer to start the request later.
  */
-int
-dasd_start_IO(struct dasd_ccw_req * cqr)
+int dasd_start_IO(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
        int rc;
+       char errorstring[ERRORLENGTH];
 
        /* Check the cqr */
        rc = dasd_check_cqr(cqr);
-       if (rc)
+       if (rc) {
+               cqr->intrc = rc;
                return rc;
-       device = (struct dasd_device *) cqr->device;
+       }
+       device = (struct dasd_device *) cqr->startdev;
        if (cqr->retries < 0) {
-               DEV_MESSAGE(KERN_DEBUG, device,
-                           "start_IO: request %p (%02x/%i) - no retry left.",
-                           cqr, cqr->status, cqr->retries);
-               cqr->status = DASD_CQR_FAILED;
+               /* internal error 14 - start_IO run out of retries */
+               sprintf(errorstring, "14 %p", cqr);
+               dev_err(&device->cdev->dev, "An error occurred in the DASD "
+                       "device driver, reason=%s\n", errorstring);
+               cqr->status = DASD_CQR_ERROR;
                return -EIO;
        }
        cqr->startclk = get_clock();
        cqr->starttime = jiffies;
        cqr->retries--;
-       rc = ccw_device_start(device->cdev, cqr->cpaddr, (long) cqr,
-                             cqr->lpm, 0);
+       if (cqr->cpmode == 1) {
+               rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
+                                        (long) cqr, cqr->lpm);
+       } else {
+               rc = ccw_device_start(device->cdev, cqr->cpaddr,
+                                     (long) cqr, cqr->lpm, 0);
+       }
        switch (rc) {
        case 0:
                cqr->status = DASD_CQR_IN_IO;
-               DBF_DEV_EVENT(DBF_DEBUG, device,
-                             "start_IO: request %p started successful",
-                             cqr);
                break;
        case -EBUSY:
-               DBF_DEV_EVENT(DBF_ERR, device, "%s",
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
                              "start_IO: device busy, retry later");
                break;
        case -ETIMEDOUT:
-               DBF_DEV_EVENT(DBF_ERR, device, "%s",
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
                              "start_IO: request timeout, retry later");
                break;
        case -EACCES:
@@ -764,22 +913,34 @@ dasd_start_IO(struct dasd_ccw_req * cqr)
                 * Do a retry with all available pathes.
                 */
                cqr->lpm = LPM_ANYPATH;
-               DBF_DEV_EVENT(DBF_ERR, device, "%s",
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
                              "start_IO: selected pathes gone,"
                              " retry on all pathes");
                break;
        case -ENODEV:
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
+                             "start_IO: -ENODEV device gone, retry");
+               break;
        case -EIO:
-               DBF_DEV_EVENT(DBF_ERR, device, "%s",
-                             "start_IO: device gone, retry");
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
+                             "start_IO: -EIO device gone, retry");
+               break;
+       case -EINVAL:
+               /* most likely caused in power management context */
+               DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
+                             "start_IO: -EINVAL device currently "
+                             "not accessible");
                break;
        default:
-               DEV_MESSAGE(KERN_ERR, device,
-                           "line %d unknown RC=%d, please report"
-                           " to linux390@de.ibm.com", __LINE__, rc);
+               /* internal error 11 - unknown rc */
+               snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
+               dev_err(&device->cdev->dev,
+                       "An error occurred in the DASD device driver, "
+                       "reason=%s\n", errorstring);
                BUG();
                break;
        }
+       cqr->intrc = rc;
        return rc;
 }
 
@@ -791,8 +952,7 @@ dasd_start_IO(struct dasd_ccw_req * cqr)
  * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
  * DASD_CQR_QUEUED for 2) and 3).
  */
-static void
-dasd_timeout_device(unsigned long ptr)
+static void dasd_device_timeout(unsigned long ptr)
 {
        unsigned long flags;
        struct dasd_device *device;
@@ -800,400 +960,291 @@ dasd_timeout_device(unsigned long ptr)
        device = (struct dasd_device *) ptr;
        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
        /* re-activate request queue */
-        device->stopped &= ~DASD_STOPPED_PENDING;
+       dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
 }
 
 /*
  * Setup timeout for a device in jiffies.
  */
-void
-dasd_set_timer(struct dasd_device *device, int expires)
+void dasd_device_set_timer(struct dasd_device *device, int expires)
 {
-       if (expires == 0) {
-               if (timer_pending(&device->timer))
-                       del_timer(&device->timer);
-               return;
-       }
-       if (timer_pending(&device->timer)) {
-               if (mod_timer(&device->timer, jiffies + expires))
-                       return;
-       }
-       device->timer.function = dasd_timeout_device;
-       device->timer.data = (unsigned long) device;
-       device->timer.expires = jiffies + expires;
-       add_timer(&device->timer);
+       if (expires == 0)
+               del_timer(&device->timer);
+       else
+               mod_timer(&device->timer, jiffies + expires);
 }
 
 /*
  * Clear timeout for a device.
  */
-void
-dasd_clear_timer(struct dasd_device *device)
+void dasd_device_clear_timer(struct dasd_device *device)
 {
-       if (timer_pending(&device->timer))
-               del_timer(&device->timer);
+       del_timer(&device->timer);
 }
 
-static void
-dasd_handle_killed_request(struct ccw_device *cdev, unsigned long intparm)
+static void dasd_handle_killed_request(struct ccw_device *cdev,
+                                      unsigned long intparm)
 {
        struct dasd_ccw_req *cqr;
        struct dasd_device *device;
 
+       if (!intparm)
+               return;
        cqr = (struct dasd_ccw_req *) intparm;
        if (cqr->status != DASD_CQR_IN_IO) {
-               MESSAGE(KERN_DEBUG,
-                       "invalid status in handle_killed_request: "
-                       "bus_id %s, status %02x",
-                       cdev->dev.bus_id, cqr->status);
+               DBF_EVENT_DEVID(DBF_DEBUG, cdev,
+                               "invalid status in handle_killed_request: "
+                               "%02x", cqr->status);
                return;
        }
 
-       device = (struct dasd_device *) cqr->device;
+       device = (struct dasd_device *) cqr->startdev;
        if (device == NULL ||
-           device != dasd_device_from_cdev(cdev) ||
+           device != dasd_device_from_cdev_locked(cdev) ||
            strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
-               MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
-                       cdev->dev.bus_id);
+               DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
+                               "invalid device in request");
                return;
        }
 
        /* Schedule request to be retried. */
        cqr->status = DASD_CQR_QUEUED;
 
-       dasd_clear_timer(device);
-       dasd_schedule_bh(device);
+       dasd_device_clear_timer(device);
+       dasd_schedule_device_bh(device);
        dasd_put_device(device);
 }
 
-static void
-dasd_handle_state_change_pending(struct dasd_device *device)
+void dasd_generic_handle_state_change(struct dasd_device *device)
 {
-       struct dasd_ccw_req *cqr;
-       struct list_head *l, *n;
-
-       device->stopped &= ~DASD_STOPPED_PENDING;
+       /* First of all start sense subsystem status request. */
+       dasd_eer_snss(device);
 
-        /* restart all 'running' IO on queue */
-       list_for_each_safe(l, n, &device->ccw_queue) {
-               cqr = list_entry(l, struct dasd_ccw_req, list);
-                if (cqr->status == DASD_CQR_IN_IO) {
-                        cqr->status = DASD_CQR_QUEUED;
-               }
-        }
-       dasd_clear_timer(device);
-       dasd_schedule_bh(device);
+       dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
+       dasd_schedule_device_bh(device);
+       if (device->block)
+               dasd_schedule_block_bh(device->block);
 }
 
 /*
  * Interrupt handler for "normal" ssch-io based dasd devices.
  */
-void
-dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
-                struct irb *irb)
+void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
+                     struct irb *irb)
 {
        struct dasd_ccw_req *cqr, *next;
        struct dasd_device *device;
        unsigned long long now;
        int expires;
-       dasd_era_t era;
-       char mask;
 
        if (IS_ERR(irb)) {
                switch (PTR_ERR(irb)) {
                case -EIO:
-                       dasd_handle_killed_request(cdev, intparm);
                        break;
                case -ETIMEDOUT:
-                       printk(KERN_WARNING"%s(%s): request timed out\n",
-                              __FUNCTION__, cdev->dev.bus_id);
-                       //FIXME - dasd uses own timeout interface...
+                       DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
+                                       "request timed out\n", __func__);
                        break;
                default:
-                       printk(KERN_WARNING"%s(%s): unknown error %ld\n",
-                              __FUNCTION__, cdev->dev.bus_id, PTR_ERR(irb));
+                       DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
+                                       "unknown error %ld\n", __func__,
+                                       PTR_ERR(irb));
                }
+               dasd_handle_killed_request(cdev, intparm);
                return;
        }
 
        now = get_clock();
 
-       DBF_EVENT(DBF_ERR, "Interrupt: bus_id %s CS/DS %04x ip %08x",
-                 cdev->dev.bus_id, ((irb->scsw.cstat<<8)|irb->scsw.dstat),
-                 (unsigned int) intparm);
-
-       /* first of all check for state change pending interrupt */
-       mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
-       if ((irb->scsw.dstat & mask) == mask) {
-               device = dasd_device_from_cdev(cdev);
+       /* check for unsolicited interrupts */
+       cqr = (struct dasd_ccw_req *) intparm;
+       if (!cqr || ((scsw_cc(&irb->scsw) == 1) &&
+                    (scsw_fctl(&irb->scsw) & SCSW_FCTL_START_FUNC) &&
+                    (scsw_stctl(&irb->scsw) & SCSW_STCTL_STATUS_PEND))) {
+               if (cqr && cqr->status == DASD_CQR_IN_IO)
+                       cqr->status = DASD_CQR_QUEUED;
+               device = dasd_device_from_cdev_locked(cdev);
                if (!IS_ERR(device)) {
-                       dasd_handle_state_change_pending(device);
+                       dasd_device_clear_timer(device);
+                       device->discipline->handle_unsolicited_interrupt(device,
+                                                                        irb);
                        dasd_put_device(device);
                }
                return;
        }
 
-       cqr = (struct dasd_ccw_req *) intparm;
-
-       /* check for unsolicited interrupts */
-       if (cqr == NULL) {
-               MESSAGE(KERN_DEBUG,
-                       "unsolicited interrupt received: bus_id %s",
-                       cdev->dev.bus_id);
-               return;
-       }
-
-       device = (struct dasd_device *) cqr->device;
-       if (device == NULL ||
+       device = (struct dasd_device *) cqr->startdev;
+       if (!device ||
            strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
-               MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
-                       cdev->dev.bus_id);
+               DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
+                               "invalid device in request");
                return;
        }
 
        /* Check for clear pending */
-       if (cqr->status == DASD_CQR_CLEAR &&
-           irb->scsw.fctl & SCSW_FCTL_CLEAR_FUNC) {
-               cqr->status = DASD_CQR_QUEUED;
-               dasd_clear_timer(device);
-               dasd_schedule_bh(device);
+       if (cqr->status == DASD_CQR_CLEAR_PENDING &&
+           scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
+               cqr->status = DASD_CQR_CLEARED;
+               dasd_device_clear_timer(device);
+               wake_up(&dasd_flush_wq);
+               dasd_schedule_device_bh(device);
                return;
        }
 
-       /* check status - the request might have been killed by dyn detach */
+       /* check status - the request might have been killed by dyn detach */
        if (cqr->status != DASD_CQR_IN_IO) {
-               MESSAGE(KERN_DEBUG,
-                       "invalid status: bus_id %s, status %02x",
-                       cdev->dev.bus_id, cqr->status);
+               DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
+                             "status %02x", dev_name(&cdev->dev), cqr->status);
                return;
        }
-       DBF_DEV_EVENT(DBF_DEBUG, device, "Int: CS/DS 0x%04x for cqr %p",
-                     ((irb->scsw.cstat << 8) | irb->scsw.dstat), cqr);
-
-       /* Find out the appropriate era_action. */
-       if (irb->scsw.fctl & SCSW_FCTL_HALT_FUNC) 
-               era = dasd_era_fatal;
-       else if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
-                irb->scsw.cstat == 0 &&
-                !irb->esw.esw0.erw.cons)
-               era = dasd_era_none;
-       else if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags))
-               era = dasd_era_fatal; /* don't recover this request */
-       else if (irb->esw.esw0.erw.cons)
-               era = device->discipline->examine_error(cqr, irb);
-       else 
-               era = dasd_era_recover;
-
-       DBF_DEV_EVENT(DBF_DEBUG, device, "era_code %d", era);
+
+       next = NULL;
        expires = 0;
-       if (era == dasd_era_none) {
-               cqr->status = DASD_CQR_DONE;
+       if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
+           scsw_cstat(&irb->scsw) == 0) {
+               /* request was completed successfully */
+               cqr->status = DASD_CQR_SUCCESS;
                cqr->stopclk = now;
                /* Start first request on queue if possible -> fast_io. */
-               if (cqr->list.next != &device->ccw_queue) {
-                       next = list_entry(cqr->list.next,
-                                         struct dasd_ccw_req, list);
-                       if ((next->status == DASD_CQR_QUEUED) &&
-                           (!device->stopped)) {
-                               if (device->discipline->start_IO(next) == 0)
-                                       expires = next->expires;
-                               else
-                                       DEV_MESSAGE(KERN_DEBUG, device, "%s",
-                                                   "Interrupt fastpath "
-                                                   "failed!");
-                       }
+               if (cqr->devlist.next != &device->ccw_queue) {
+                       next = list_entry(cqr->devlist.next,
+                                         struct dasd_ccw_req, devlist);
                }
-       } else {                /* error */
-               memcpy(&cqr->irb, irb, sizeof (struct irb));
-#ifdef ERP_DEBUG
-               /* dump sense data */
-               dasd_log_sense(cqr, irb);
-#endif
-               switch (era) {
-               case dasd_era_fatal:
-                       cqr->status = DASD_CQR_FAILED;
-                       cqr->stopclk = now;
-                       break;
-               case dasd_era_recover:
-                       cqr->status = DASD_CQR_ERROR;
-                       break;
-               default:
-                       BUG();
+       } else {  /* error */
+               memcpy(&cqr->irb, irb, sizeof(struct irb));
+               /* log sense for every failed I/O to s390 debugfeature */
+               dasd_log_sense_dbf(cqr, irb);
+               if (device->features & DASD_FEATURE_ERPLOG) {
+                       dasd_log_sense(cqr, irb);
                }
+
+               /*
+                * If we don't want complex ERP for this request, then just
+                * reset this and retry it in the fastpath
+                */
+               if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
+                   cqr->retries > 0) {
+                       if (cqr->lpm == LPM_ANYPATH)
+                               DBF_DEV_EVENT(DBF_DEBUG, device,
+                                             "default ERP in fastpath "
+                                             "(%i retries left)",
+                                             cqr->retries);
+                       cqr->lpm    = LPM_ANYPATH;
+                       cqr->status = DASD_CQR_QUEUED;
+                       next = cqr;
+               } else
+                       cqr->status = DASD_CQR_ERROR;
+       }
+       if (next && (next->status == DASD_CQR_QUEUED) &&
+           (!device->stopped)) {
+               if (device->discipline->start_IO(next) == 0)
+                       expires = next->expires;
        }
        if (expires != 0)
-               dasd_set_timer(device, expires);
+               dasd_device_set_timer(device, expires);
        else
-               dasd_clear_timer(device);
-       dasd_schedule_bh(device);
+               dasd_device_clear_timer(device);
+       dasd_schedule_device_bh(device);
 }
 
 /*
- * posts the buffer_cache about a finalized request
+ * If we have an error on a dasd_block layer request then we cancel
+ * and return all further requests from the same dasd_block as well.
  */
-static inline void
-dasd_end_request(struct request *req, int uptodate)
+static void __dasd_device_recovery(struct dasd_device *device,
+                                  struct dasd_ccw_req *ref_cqr)
 {
-       if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
-               BUG();
-       add_disk_randomness(req->rq_disk);
-       end_that_request_last(req);
-}
+       struct list_head *l, *n;
+       struct dasd_ccw_req *cqr;
 
-/*
- * Process finished error recovery ccw.
- */
-static inline void
-__dasd_process_erp(struct dasd_device *device, struct dasd_ccw_req *cqr)
-{
-       dasd_erp_fn_t erp_fn;
+       /*
+        * only requeue request that came from the dasd_block layer
+        */
+       if (!ref_cqr->block)
+               return;
 
-       if (cqr->status == DASD_CQR_DONE)
-               DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
-       else
-               DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful");
-       erp_fn = device->discipline->erp_postaction(cqr);
-       erp_fn(cqr);
-}
+       list_for_each_safe(l, n, &device->ccw_queue) {
+               cqr = list_entry(l, struct dasd_ccw_req, devlist);
+               if (cqr->status == DASD_CQR_QUEUED &&
+                   ref_cqr->block == cqr->block) {
+                       cqr->status = DASD_CQR_CLEARED;
+               }
+       }
+};
 
 /*
- * Process ccw request queue.
+ * Remove those ccw requests from the queue that need to be returned
+ * to the upper layer.
  */
-static inline void
-__dasd_process_ccw_queue(struct dasd_device * device,
-                        struct list_head *final_queue)
+static void __dasd_device_process_ccw_queue(struct dasd_device *device,
+                                           struct list_head *final_queue)
 {
        struct list_head *l, *n;
        struct dasd_ccw_req *cqr;
-       dasd_erp_fn_t erp_fn;
 
-restart:
        /* Process request with final status. */
        list_for_each_safe(l, n, &device->ccw_queue) {
-               cqr = list_entry(l, struct dasd_ccw_req, list);
+               cqr = list_entry(l, struct dasd_ccw_req, devlist);
+
                /* Stop list processing at the first non-final request. */
-               if (cqr->status != DASD_CQR_DONE &&
-                   cqr->status != DASD_CQR_FAILED &&
-                   cqr->status != DASD_CQR_ERROR)
+               if (cqr->status == DASD_CQR_QUEUED ||
+                   cqr->status == DASD_CQR_IN_IO ||
+                   cqr->status == DASD_CQR_CLEAR_PENDING)
                        break;
-               /*  Process requests with DASD_CQR_ERROR */
                if (cqr->status == DASD_CQR_ERROR) {
-                       if (cqr->irb.scsw.fctl & SCSW_FCTL_HALT_FUNC) {
-                               cqr->status = DASD_CQR_FAILED;
-                               cqr->stopclk = get_clock();
-                       } else {
-                               if (cqr->irb.esw.esw0.erw.cons) {
-                                       erp_fn = device->discipline->
-                                               erp_action(cqr);
-                                       erp_fn(cqr);
-                               } else
-                                       dasd_default_erp_action(cqr);
-                       }
-                       goto restart;
-               }
-               /* Process finished ERP request. */
-               if (cqr->refers) {
-                       __dasd_process_erp(device, cqr);
-                       goto restart;
+                       __dasd_device_recovery(device, cqr);
                }
-
                /* Rechain finished requests to final queue */
-               cqr->endclk = get_clock();
-               list_move_tail(&cqr->list, final_queue);
+               list_move_tail(&cqr->devlist, final_queue);
        }
 }
 
-static void
-dasd_end_request_cb(struct dasd_ccw_req * cqr, void *data)
-{
-       struct request *req;
-       struct dasd_device *device;
-       int status;
-
-       req = (struct request *) data;
-       device = cqr->device;
-       dasd_profile_end(device, cqr, req);
-       status = cqr->device->discipline->free_cp(cqr,req);
-       spin_lock_irq(&device->request_queue_lock);
-       dasd_end_request(req, status);
-       spin_unlock_irq(&device->request_queue_lock);
-}
-
-
 /*
- * Fetch requests from the block device queue.
+ * the cqrs from the final queue are returned to the upper layer
+ * by setting a dasd_block state and calling the callback function
  */
-static inline void
-__dasd_process_blk_queue(struct dasd_device * device)
+static void __dasd_device_process_final_queue(struct dasd_device *device,
+                                             struct list_head *final_queue)
 {
-       request_queue_t *queue;
-       struct request *req;
+       struct list_head *l, *n;
        struct dasd_ccw_req *cqr;
-       int nr_queued, feature_ro;
-
-       queue = device->request_queue;
-       /* No queue ? Then there is nothing to do. */
-       if (queue == NULL)
-               return;
-
-       feature_ro = dasd_get_feature(device->cdev, DASD_FEATURE_READONLY);
-       if (feature_ro < 0)     /* no devmap */
-               return;
-
-       /*
-        * We requeue request from the block device queue to the ccw
-        * queue only in two states. In state DASD_STATE_READY the
-        * partition detection is done and we need to requeue requests
-        * for that. State DASD_STATE_ONLINE is normal block device
-        * operation.
-        */
-       if (device->state != DASD_STATE_READY &&
-           device->state != DASD_STATE_ONLINE)
-               return;
-       nr_queued = 0;
-       /* Now we try to fetch requests from the request queue */
-       list_for_each_entry(cqr, &device->ccw_queue, list)
-               if (cqr->status == DASD_CQR_QUEUED)
-                       nr_queued++;
-       while (!blk_queue_plugged(queue) &&
-              elv_next_request(queue) &&
-               nr_queued < DASD_CHANQ_MAX_SIZE) {
-               req = elv_next_request(queue);
-
-               if (feature_ro && rq_data_dir(req) == WRITE) {
-                       DBF_DEV_EVENT(DBF_ERR, device,
-                                     "Rejecting write request %p",
-                                     req);
-                       blkdev_dequeue_request(req);
-                       dasd_end_request(req, 0);
-                       continue;
-               }
-               if (device->stopped & DASD_STOPPED_DC_EIO) {
-                       blkdev_dequeue_request(req);
-                       dasd_end_request(req, 0);
-                       continue;
-               }
-               cqr = device->discipline->build_cp(device, req);
-               if (IS_ERR(cqr)) {
-                       if (PTR_ERR(cqr) == -ENOMEM)
-                               break;  /* terminate request queue loop */
-                       DBF_DEV_EVENT(DBF_ERR, device,
-                                     "CCW creation failed (rc=%ld) "
-                                     "on request %p",
-                                     PTR_ERR(cqr), req);
-                       blkdev_dequeue_request(req);
-                       dasd_end_request(req, 0);
-                       continue;
+       struct dasd_block *block;
+       void (*callback)(struct dasd_ccw_req *, void *data);
+       void *callback_data;
+       char errorstring[ERRORLENGTH];
+
+       list_for_each_safe(l, n, final_queue) {
+               cqr = list_entry(l, struct dasd_ccw_req, devlist);
+               list_del_init(&cqr->devlist);
+               block = cqr->block;
+               callback = cqr->callback;
+               callback_data = cqr->callback_data;
+               if (block)
+                       spin_lock_bh(&block->queue_lock);
+               switch (cqr->status) {
+               case DASD_CQR_SUCCESS:
+                       cqr->status = DASD_CQR_DONE;
+                       break;
+               case DASD_CQR_ERROR:
+                       cqr->status = DASD_CQR_NEED_ERP;
+                       break;
+               case DASD_CQR_CLEARED:
+                       cqr->status = DASD_CQR_TERMINATED;
+                       break;
+               default:
+                       /* internal error 12 - wrong cqr status*/
+                       snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
+                       dev_err(&device->cdev->dev,
+                               "An error occurred in the DASD device driver, "
+                               "reason=%s\n", errorstring);
+                       BUG();
                }
-               cqr->callback = dasd_end_request_cb;
-               cqr->callback_data = (void *) req;
-               cqr->status = DASD_CQR_QUEUED;
-               blkdev_dequeue_request(req);
-               list_add_tail(&cqr->list, &device->ccw_queue);
-               dasd_profile_start(device, cqr, req);
-               nr_queued++;
+               if (cqr->callback != NULL)
+                       (callback)(cqr, callback_data);
+               if (block)
+                       spin_unlock_bh(&block->queue_lock);
        }
 }
 
@@ -1201,19 +1252,28 @@ __dasd_process_blk_queue(struct dasd_device * device)
  * Take a look at the first request on the ccw queue and check
  * if it reached its expire time. If so, terminate the IO.
  */
-static inline void
-__dasd_check_expire(struct dasd_device * device)
+static void __dasd_device_check_expire(struct dasd_device *device)
 {
        struct dasd_ccw_req *cqr;
 
        if (list_empty(&device->ccw_queue))
                return;
-       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
-       if (cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) {
-               if (time_after_eq(jiffies, cqr->expires + cqr->starttime)) {
-                       if (device->discipline->term_IO(cqr) != 0)
-                               /* Hmpf, try again in 1/10 sec */
-                               dasd_set_timer(device, 10);
+       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
+       if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
+           (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
+               if (device->discipline->term_IO(cqr) != 0) {
+                       /* Hmpf, try again in 5 sec */
+                       dev_err(&device->cdev->dev,
+                               "cqr %p timed out (%is) but cannot be "
+                               "ended, retrying in 5 s\n",
+                               cqr, (cqr->expires/HZ));
+                       cqr->expires += 5*HZ;
+                       dasd_device_set_timer(device, 5*HZ);
+               } else {
+                       dev_err(&device->cdev->dev,
+                               "cqr %p timed out (%is), %i retries "
+                               "remaining\n", cqr, (cqr->expires/HZ),
+                               cqr->retries);
                }
        }
 }
@@ -1222,311 +1282,381 @@ __dasd_check_expire(struct dasd_device * device)
  * Take a look at the first request on the ccw queue and check
  * if it needs to be started.
  */
-static inline void
-__dasd_start_head(struct dasd_device * device)
+static void __dasd_device_start_head(struct dasd_device *device)
 {
        struct dasd_ccw_req *cqr;
        int rc;
 
        if (list_empty(&device->ccw_queue))
                return;
-       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
-       if ((cqr->status == DASD_CQR_QUEUED) &&
-           (!device->stopped)) {
-               /* try to start the first I/O that can be started */
-               rc = device->discipline->start_IO(cqr);
-               if (rc == 0)
-                       dasd_set_timer(device, cqr->expires);
-               else if (rc == -EACCES) {
-                       dasd_schedule_bh(device);
-               } else
-                       /* Hmpf, try again in 1/2 sec */
-                       dasd_set_timer(device, 50);
+       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
+       if (cqr->status != DASD_CQR_QUEUED)
+               return;
+       /* when device is stopped, return request to previous layer */
+       if (device->stopped) {
+               cqr->status = DASD_CQR_CLEARED;
+               dasd_schedule_device_bh(device);
+               return;
        }
+
+       rc = device->discipline->start_IO(cqr);
+       if (rc == 0)
+               dasd_device_set_timer(device, cqr->expires);
+       else if (rc == -EACCES) {
+               dasd_schedule_device_bh(device);
+       } else
+               /* Hmpf, try again in 1/2 sec */
+               dasd_device_set_timer(device, 50);
 }
 
 /*
- * Remove requests from the ccw queue. 
+ * Go through all request on the dasd_device request queue,
+ * terminate them on the cdev if necessary, and return them to the
+ * submitting layer via callback.
+ * Note:
+ * Make sure that all 'submitting layers' still exist when
+ * this function is called!. In other words, when 'device' is a base
+ * device then all block layer requests must have been removed before
+ * via dasd_flush_block_queue.
  */
-static void
-dasd_flush_ccw_queue(struct dasd_device * device, int all)
+int dasd_flush_device_queue(struct dasd_device *device)
 {
+       struct dasd_ccw_req *cqr, *n;
+       int rc;
        struct list_head flush_queue;
-       struct list_head *l, *n;
-       struct dasd_ccw_req *cqr;
 
        INIT_LIST_HEAD(&flush_queue);
        spin_lock_irq(get_ccwdev_lock(device->cdev));
-       list_for_each_safe(l, n, &device->ccw_queue) {
-               cqr = list_entry(l, struct dasd_ccw_req, list);
-               /* Flush all request or only block device requests? */
-               if (all == 0 && cqr->callback == dasd_end_request_cb)
-                       continue;
-               if (cqr->status == DASD_CQR_IN_IO)
-                       device->discipline->term_IO(cqr);
-               if (cqr->status != DASD_CQR_DONE ||
-                   cqr->status != DASD_CQR_FAILED) {
-                       cqr->status = DASD_CQR_FAILED;
+       rc = 0;
+       list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
+               /* Check status and move request to flush_queue */
+               switch (cqr->status) {
+               case DASD_CQR_IN_IO:
+                       rc = device->discipline->term_IO(cqr);
+                       if (rc) {
+                               /* unable to terminate requeust */
+                               dev_err(&device->cdev->dev,
+                                       "Flushing the DASD request queue "
+                                       "failed for request %p\n", cqr);
+                               /* stop flush processing */
+                               goto finished;
+                       }
+                       break;
+               case DASD_CQR_QUEUED:
                        cqr->stopclk = get_clock();
+                       cqr->status = DASD_CQR_CLEARED;
+                       break;
+               default: /* no need to modify the others */
+                       break;
                }
-               /* Process finished ERP request. */
-               if (cqr->refers) {
-                       __dasd_process_erp(device, cqr);
-                       continue;
-               }
-               /* Rechain request on device request queue */
-               cqr->endclk = get_clock();
-               list_move_tail(&cqr->list, &flush_queue);
+               list_move_tail(&cqr->devlist, &flush_queue);
        }
+finished:
        spin_unlock_irq(get_ccwdev_lock(device->cdev));
-       /* Now call the callback function of flushed requests */
-       list_for_each_safe(l, n, &flush_queue) {
-               cqr = list_entry(l, struct dasd_ccw_req, list);
-               if (cqr->callback != NULL)
-                       (cqr->callback)(cqr, cqr->callback_data);
-       }
+       /*
+        * After this point all requests must be in state CLEAR_PENDING,
+        * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
+        * one of the others.
+        */
+       list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
+               wait_event(dasd_flush_wq,
+                          (cqr->status != DASD_CQR_CLEAR_PENDING));
+       /*
+        * Now set each request back to TERMINATED, DONE or NEED_ERP
+        * and call the callback function of flushed requests
+        */
+       __dasd_device_process_final_queue(device, &flush_queue);
+       return rc;
 }
 
 /*
  * Acquire the device lock and process queues for the device.
  */
-static void
-dasd_tasklet(struct dasd_device * device)
+static void dasd_device_tasklet(struct dasd_device *device)
 {
        struct list_head final_queue;
-       struct list_head *l, *n;
-       struct dasd_ccw_req *cqr;
 
        atomic_set (&device->tasklet_scheduled, 0);
        INIT_LIST_HEAD(&final_queue);
        spin_lock_irq(get_ccwdev_lock(device->cdev));
        /* Check expire time of first request on the ccw queue. */
-       __dasd_check_expire(device);
-       /* Finish off requests on ccw queue */
-       __dasd_process_ccw_queue(device, &final_queue);
+       __dasd_device_check_expire(device);
+       /* find final requests on ccw queue */
+       __dasd_device_process_ccw_queue(device, &final_queue);
        spin_unlock_irq(get_ccwdev_lock(device->cdev));
        /* Now call the callback function of requests with final status */
-       list_for_each_safe(l, n, &final_queue) {
-               cqr = list_entry(l, struct dasd_ccw_req, list);
-               list_del(&cqr->list);
-               if (cqr->callback != NULL)
-                       (cqr->callback)(cqr, cqr->callback_data);
-       }
-       spin_lock_irq(&device->request_queue_lock);
-       spin_lock(get_ccwdev_lock(device->cdev));
-       /* Get new request from the block device request queue */
-       __dasd_process_blk_queue(device);
+       __dasd_device_process_final_queue(device, &final_queue);
+       spin_lock_irq(get_ccwdev_lock(device->cdev));
        /* Now check if the head of the ccw queue needs to be started. */
-       __dasd_start_head(device);
-       spin_unlock(get_ccwdev_lock(device->cdev));
-       spin_unlock_irq(&device->request_queue_lock);
+       __dasd_device_start_head(device);
+       spin_unlock_irq(get_ccwdev_lock(device->cdev));
        dasd_put_device(device);
 }
 
 /*
  * Schedules a call to dasd_tasklet over the device tasklet.
  */
-void
-dasd_schedule_bh(struct dasd_device * device)
+void dasd_schedule_device_bh(struct dasd_device *device)
 {
        /* Protect against rescheduling. */
-       if (atomic_compare_and_swap (0, 1, &device->tasklet_scheduled))
+       if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
                return;
        dasd_get_device(device);
        tasklet_hi_schedule(&device->tasklet);
 }
 
+void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
+{
+       device->stopped |= bits;
+}
+EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
+
+void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
+{
+       device->stopped &= ~bits;
+       if (!device->stopped)
+               wake_up(&generic_waitq);
+}
+EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
+
 /*
- * Queue a request to the head of the ccw_queue. Start the I/O if
- * possible.
+ * Queue a request to the head of the device ccw_queue.
+ * Start the I/O if possible.
  */
-void
-dasd_add_request_head(struct dasd_ccw_req *req)
+void dasd_add_request_head(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
        unsigned long flags;
 
-       device = req->device;
+       device = cqr->startdev;
        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
-       req->status = DASD_CQR_QUEUED;
-       req->device = device;
-       list_add(&req->list, &device->ccw_queue);
+       cqr->status = DASD_CQR_QUEUED;
+       list_add(&cqr->devlist, &device->ccw_queue);
        /* let the bh start the request to keep them in order */
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 }
 
 /*
- * Queue a request to the tail of the ccw_queue. Start the I/O if
- * possible.
+ * Queue a request to the tail of the device ccw_queue.
+ * Start the I/O if possible.
  */
-void
-dasd_add_request_tail(struct dasd_ccw_req *req)
+void dasd_add_request_tail(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
        unsigned long flags;
 
-       device = req->device;
+       device = cqr->startdev;
        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
-       req->status = DASD_CQR_QUEUED;
-       req->device = device;
-       list_add_tail(&req->list, &device->ccw_queue);
+       cqr->status = DASD_CQR_QUEUED;
+       list_add_tail(&cqr->devlist, &device->ccw_queue);
        /* let the bh start the request to keep them in order */
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 }
 
 /*
- * Wakeup callback.
+ * Wakeup helper for the 'sleep_on' functions.
  */
-static void
-dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
+static void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
 {
        wake_up((wait_queue_head_t *) data);
 }
 
-static inline int
-_wait_for_wakeup(struct dasd_ccw_req *cqr)
+static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
 {
        struct dasd_device *device;
        int rc;
 
-       device = cqr->device;
+       device = cqr->startdev;
        spin_lock_irq(get_ccwdev_lock(device->cdev));
-       rc = cqr->status == DASD_CQR_DONE || cqr->status == DASD_CQR_FAILED;
+       rc = ((cqr->status == DASD_CQR_DONE ||
+              cqr->status == DASD_CQR_NEED_ERP ||
+              cqr->status == DASD_CQR_TERMINATED) &&
+             list_empty(&cqr->devlist));
        spin_unlock_irq(get_ccwdev_lock(device->cdev));
        return rc;
 }
 
 /*
- * Attempts to start a special ccw queue and waits for its completion.
+ * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
  */
-int
-dasd_sleep_on(struct dasd_ccw_req * cqr)
+static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
 {
-       wait_queue_head_t wait_q;
        struct dasd_device *device;
-       int rc;
-       
-       device = cqr->device;
-       spin_lock_irq(get_ccwdev_lock(device->cdev));
-       
-       init_waitqueue_head (&wait_q);
-       cqr->callback = dasd_wakeup_cb;
-       cqr->callback_data = (void *) &wait_q;
-       cqr->status = DASD_CQR_QUEUED;
-       list_add_tail(&cqr->list, &device->ccw_queue);
-       
-       /* let the bh start the request to keep them in order */
-       dasd_schedule_bh(device);
-       
-       spin_unlock_irq(get_ccwdev_lock(device->cdev));
+       dasd_erp_fn_t erp_fn;
 
-       wait_event(wait_q, _wait_for_wakeup(cqr));
-       
-       /* Request status is either done or failed. */
-       rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
-       return rc;
+       if (cqr->status == DASD_CQR_FILLED)
+               return 0;
+       device = cqr->startdev;
+       if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
+               if (cqr->status == DASD_CQR_TERMINATED) {
+                       device->discipline->handle_terminated_request(cqr);
+                       return 1;
+               }
+               if (cqr->status == DASD_CQR_NEED_ERP) {
+                       erp_fn = device->discipline->erp_action(cqr);
+                       erp_fn(cqr);
+                       return 1;
+               }
+               if (cqr->status == DASD_CQR_FAILED)
+                       dasd_log_sense(cqr, &cqr->irb);
+               if (cqr->refers) {
+                       __dasd_process_erp(device, cqr);
+                       return 1;
+               }
+       }
+       return 0;
 }
 
-/*
- * Attempts to start a special ccw queue and wait interruptible
- * for its completion.
- */
-int
-dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)
+static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
 {
-       wait_queue_head_t wait_q;
-       struct dasd_device *device;
-       int rc, finished;
+       if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
+               if (cqr->refers) /* erp is not done yet */
+                       return 1;
+               return ((cqr->status != DASD_CQR_DONE) &&
+                       (cqr->status != DASD_CQR_FAILED));
+       } else
+               return (cqr->status == DASD_CQR_FILLED);
+}
 
-       device = cqr->device;
-       spin_lock_irq(get_ccwdev_lock(device->cdev));
+static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
+{
+       struct dasd_device *device;
+       int rc;
+       struct list_head ccw_queue;
+       struct dasd_ccw_req *cqr;
 
-       init_waitqueue_head (&wait_q);
-       cqr->callback = dasd_wakeup_cb;
-       cqr->callback_data = (void *) &wait_q;
-       cqr->status = DASD_CQR_QUEUED;
-       list_add_tail(&cqr->list, &device->ccw_queue);
+       INIT_LIST_HEAD(&ccw_queue);
+       maincqr->status = DASD_CQR_FILLED;
+       device = maincqr->startdev;
+       list_add(&maincqr->blocklist, &ccw_queue);
+       for (cqr = maincqr;  __dasd_sleep_on_loop_condition(cqr);
+            cqr = list_first_entry(&ccw_queue,
+                                   struct dasd_ccw_req, blocklist)) {
 
-       /* let the bh start the request to keep them in order */
-       dasd_schedule_bh(device);
-       spin_unlock_irq(get_ccwdev_lock(device->cdev));
+               if (__dasd_sleep_on_erp(cqr))
+                       continue;
+               if (cqr->status != DASD_CQR_FILLED) /* could be failed */
+                       continue;
 
-       finished = 0;
-       while (!finished) {
-               rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr));
-               if (rc != -ERESTARTSYS) {
-                       /* Request status is either done or failed. */
-                       rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
-                       break;
-               }
-               spin_lock_irq(get_ccwdev_lock(device->cdev));
-               if (cqr->status == DASD_CQR_IN_IO &&
-                   device->discipline->term_IO(cqr) == 0) {
-                       list_del(&cqr->list);
-                       finished = 1;
+               /* Non-temporary stop condition will trigger fail fast */
+               if (device->stopped & ~DASD_STOPPED_PENDING &&
+                   test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
+                   (!dasd_eer_enabled(device))) {
+                       cqr->status = DASD_CQR_FAILED;
+                       continue;
                }
-               spin_unlock_irq(get_ccwdev_lock(device->cdev));
+
+               /* Don't try to start requests if device is stopped */
+               if (interruptible) {
+                       rc = wait_event_interruptible(
+                               generic_waitq, !(device->stopped));
+                       if (rc == -ERESTARTSYS) {
+                               cqr->status = DASD_CQR_FAILED;
+                               maincqr->intrc = rc;
+                               continue;
+                       }
+               } else
+                       wait_event(generic_waitq, !(device->stopped));
+
+               cqr->callback = dasd_wakeup_cb;
+               cqr->callback_data = (void *) &generic_waitq;
+               dasd_add_request_tail(cqr);
+               if (interruptible) {
+                       rc = wait_event_interruptible(
+                               generic_waitq, _wait_for_wakeup(cqr));
+                       if (rc == -ERESTARTSYS) {
+                               dasd_cancel_req(cqr);
+                               /* wait (non-interruptible) for final status */
+                               wait_event(generic_waitq,
+                                          _wait_for_wakeup(cqr));
+                               cqr->status = DASD_CQR_FAILED;
+                               maincqr->intrc = rc;
+                               continue;
+                       }
+               } else
+                       wait_event(generic_waitq, _wait_for_wakeup(cqr));
        }
+
+       maincqr->endclk = get_clock();
+       if ((maincqr->status != DASD_CQR_DONE) &&
+           (maincqr->intrc != -ERESTARTSYS))
+               dasd_log_sense(maincqr, &maincqr->irb);
+       if (maincqr->status == DASD_CQR_DONE)
+               rc = 0;
+       else if (maincqr->intrc)
+               rc = maincqr->intrc;
+       else
+               rc = -EIO;
        return rc;
 }
 
 /*
+ * Queue a request to the tail of the device ccw_queue and wait for
+ * it's completion.
+ */
+int dasd_sleep_on(struct dasd_ccw_req *cqr)
+{
+       return _dasd_sleep_on(cqr, 0);
+}
+
+/*
+ * Queue a request to the tail of the device ccw_queue and wait
+ * interruptible for it's completion.
+ */
+int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
+{
+       return _dasd_sleep_on(cqr, 1);
+}
+
+/*
  * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
  * for eckd devices) the currently running request has to be terminated
  * and be put back to status queued, before the special request is added
  * to the head of the queue. Then the special request is waited on normally.
  */
-static inline int
-_dasd_term_running_cqr(struct dasd_device *device)
+static inline int _dasd_term_running_cqr(struct dasd_device *device)
 {
        struct dasd_ccw_req *cqr;
-       int rc;
 
        if (list_empty(&device->ccw_queue))
                return 0;
-       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
-       rc = device->discipline->term_IO(cqr);
-       if (rc == 0) {
-               /* termination successful */
-               cqr->status = DASD_CQR_QUEUED;
-               cqr->startclk = cqr->stopclk = 0;
-               cqr->starttime = 0;
-       }
-       return rc;
+       cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
+       return device->discipline->term_IO(cqr);
 }
 
-int
-dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)
+int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
 {
-       wait_queue_head_t wait_q;
        struct dasd_device *device;
        int rc;
-       
-       device = cqr->device;
+
+       device = cqr->startdev;
        spin_lock_irq(get_ccwdev_lock(device->cdev));
        rc = _dasd_term_running_cqr(device);
        if (rc) {
                spin_unlock_irq(get_ccwdev_lock(device->cdev));
                return rc;
        }
-       
-       init_waitqueue_head (&wait_q);
+
        cqr->callback = dasd_wakeup_cb;
-       cqr->callback_data = (void *) &wait_q;
+       cqr->callback_data = (void *) &generic_waitq;
        cqr->status = DASD_CQR_QUEUED;
-       list_add(&cqr->list, &device->ccw_queue);
-       
+       list_add(&cqr->devlist, &device->ccw_queue);
+
        /* let the bh start the request to keep them in order */
-       dasd_schedule_bh(device);
-       
+       dasd_schedule_device_bh(device);
+
        spin_unlock_irq(get_ccwdev_lock(device->cdev));
 
-       wait_event(wait_q, _wait_for_wakeup(cqr));
-       
-       /* Request status is either done or failed. */
-       rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
+       wait_event(generic_waitq, _wait_for_wakeup(cqr));
+
+       if (cqr->status == DASD_CQR_DONE)
+               rc = 0;
+       else if (cqr->intrc)
+               rc = cqr->intrc;
+       else
+               rc = -EIO;
        return rc;
 }
 
@@ -1535,11 +1665,14 @@ dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)
  * This is useful to timeout requests. The request will be
  * terminated if it is currently in i/o.
  * Returns 1 if the request has been terminated.
+ *        0 if there was no need to terminate the request (not started yet)
+ *        negative error code if termination failed
+ * Cancellation of a request is an asynchronous operation! The calling
+ * function has to wait until the request is properly returned via callback.
  */
-int
-dasd_cancel_req(struct dasd_ccw_req *cqr)
+int dasd_cancel_req(struct dasd_ccw_req *cqr)
 {
-       struct dasd_device *device = cqr->device;
+       struct dasd_device *device = cqr->startdev;
        unsigned long flags;
        int rc;
 
@@ -1547,74 +1680,441 @@ dasd_cancel_req(struct dasd_ccw_req *cqr)
        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
        switch (cqr->status) {
        case DASD_CQR_QUEUED:
-               /* request was not started - just set to failed */
-               cqr->status = DASD_CQR_FAILED;
+               /* request was not started - just set to cleared */
+               cqr->status = DASD_CQR_CLEARED;
                break;
        case DASD_CQR_IN_IO:
                /* request in IO - terminate IO and release again */
-               if (device->discipline->term_IO(cqr) != 0)
-                       /* what to do if unable to terminate ??????
-                          e.g. not _IN_IO */
-                       cqr->status = DASD_CQR_FAILED;
-               cqr->stopclk = get_clock();
-               rc = 1;
+               rc = device->discipline->term_IO(cqr);
+               if (rc) {
+                       dev_err(&device->cdev->dev,
+                               "Cancelling request %p failed with rc=%d\n",
+                               cqr, rc);
+               } else {
+                       cqr->stopclk = get_clock();
+                       rc = 1;
+               }
                break;
-       case DASD_CQR_DONE:
-       case DASD_CQR_FAILED:
-               /* already finished - do nothing */
+       default: /* already finished or clear pending - do nothing */
                break;
-       default:
-               DEV_MESSAGE(KERN_ALERT, device,
-                           "invalid status %02x in request",
-                           cqr->status);
-               BUG();
-
        }
        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
-       dasd_schedule_bh(device);
+       dasd_schedule_device_bh(device);
+       return rc;
+}
+
+
+/*
+ * SECTION: Operations of the dasd_block layer.
+ */
+
+/*
+ * Timeout function for dasd_block. This is used when the block layer
+ * is waiting for something that may not come reliably, (e.g. a state
+ * change interrupt)
+ */
+static void dasd_block_timeout(unsigned long ptr)
+{
+       unsigned long flags;
+       struct dasd_block *block;
+
+       block = (struct dasd_block *) ptr;
+       spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
+       /* re-activate request queue */
+       dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
+       spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
+       dasd_schedule_block_bh(block);
+}
+
+/*
+ * Setup timeout for a dasd_block in jiffies.
+ */
+void dasd_block_set_timer(struct dasd_block *block, int expires)
+{
+       if (expires == 0)
+               del_timer(&block->timer);
+       else
+               mod_timer(&block->timer, jiffies + expires);
+}
+
+/*
+ * Clear timeout for a dasd_block.
+ */
+void dasd_block_clear_timer(struct dasd_block *block)
+{
+       del_timer(&block->timer);
+}
+
+/*
+ * Process finished error recovery ccw.
+ */
+static void __dasd_process_erp(struct dasd_device *device,
+                              struct dasd_ccw_req *cqr)
+{
+       dasd_erp_fn_t erp_fn;
+
+       if (cqr->status == DASD_CQR_DONE)
+               DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
+       else
+               dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
+       erp_fn = device->discipline->erp_postaction(cqr);
+       erp_fn(cqr);
+}
+
+/*
+ * Fetch requests from the block device queue.
+ */
+static void __dasd_process_request_queue(struct dasd_block *block)
+{
+       struct request_queue *queue;
+       struct request *req;
+       struct dasd_ccw_req *cqr;
+       struct dasd_device *basedev;
+       unsigned long flags;
+       queue = block->request_queue;
+       basedev = block->base;
+       /* No queue ? Then there is nothing to do. */
+       if (queue == NULL)
+               return;
+
+       /*
+        * We requeue request from the block device queue to the ccw
+        * queue only in two states. In state DASD_STATE_READY the
+        * partition detection is done and we need to requeue requests
+        * for that. State DASD_STATE_ONLINE is normal block device
+        * operation.
+        */
+       if (basedev->state < DASD_STATE_READY) {
+               while ((req = blk_fetch_request(block->request_queue)))
+                       __blk_end_request_all(req, -EIO);
+               return;
+       }
+       /* Now we try to fetch requests from the request queue */
+       while (!blk_queue_plugged(queue) && (req = blk_peek_request(queue))) {
+               if (basedev->features & DASD_FEATURE_READONLY &&
+                   rq_data_dir(req) == WRITE) {
+                       DBF_DEV_EVENT(DBF_ERR, basedev,
+                                     "Rejecting write request %p",
+                                     req);
+                       blk_start_request(req);
+                       __blk_end_request_all(req, -EIO);
+                       continue;
+               }
+               cqr = basedev->discipline->build_cp(basedev, block, req);
+               if (IS_ERR(cqr)) {
+                       if (PTR_ERR(cqr) == -EBUSY)
+                               break;  /* normal end condition */
+                       if (PTR_ERR(cqr) == -ENOMEM)
+                               break;  /* terminate request queue loop */
+                       if (PTR_ERR(cqr) == -EAGAIN) {
+                               /*
+                                * The current request cannot be build right
+                                * now, we have to try later. If this request
+                                * is the head-of-queue we stop the device
+                                * for 1/2 second.
+                                */
+                               if (!list_empty(&block->ccw_queue))
+                                       break;
+                               spin_lock_irqsave(
+                                       get_ccwdev_lock(basedev->cdev), flags);
+                               dasd_device_set_stop_bits(basedev,
+                                                         DASD_STOPPED_PENDING);
+                               spin_unlock_irqrestore(
+                                       get_ccwdev_lock(basedev->cdev), flags);
+                               dasd_block_set_timer(block, HZ/2);
+                               break;
+                       }
+                       DBF_DEV_EVENT(DBF_ERR, basedev,
+                                     "CCW creation failed (rc=%ld) "
+                                     "on request %p",
+                                     PTR_ERR(cqr), req);
+                       blk_start_request(req);
+                       __blk_end_request_all(req, -EIO);
+                       continue;
+               }
+               /*
+                *  Note: callback is set to dasd_return_cqr_cb in
+                * __dasd_block_start_head to cover erp requests as well
+                */
+               cqr->callback_data = (void *) req;
+               cqr->status = DASD_CQR_FILLED;
+               blk_start_request(req);
+               list_add_tail(&cqr->blocklist, &block->ccw_queue);
+               dasd_profile_start(block, cqr, req);
+       }
+}
+
+static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
+{
+       struct request *req;
+       int status;
+       int error = 0;
+
+       req = (struct request *) cqr->callback_data;
+       dasd_profile_end(cqr->block, cqr, req);
+       status = cqr->block->base->discipline->free_cp(cqr, req);
+       if (status <= 0)
+               error = status ? status : -EIO;
+       __blk_end_request_all(req, error);
+}
+
+/*
+ * Process ccw request queue.
+ */
+static void __dasd_process_block_ccw_queue(struct dasd_block *block,
+                                          struct list_head *final_queue)
+{
+       struct list_head *l, *n;
+       struct dasd_ccw_req *cqr;
+       dasd_erp_fn_t erp_fn;
+       unsigned long flags;
+       struct dasd_device *base = block->base;
+
+restart:
+       /* Process request with final status. */
+       list_for_each_safe(l, n, &block->ccw_queue) {
+               cqr = list_entry(l, struct dasd_ccw_req, blocklist);
+               if (cqr->status != DASD_CQR_DONE &&
+                   cqr->status != DASD_CQR_FAILED &&
+                   cqr->status != DASD_CQR_NEED_ERP &&
+                   cqr->status != DASD_CQR_TERMINATED)
+                       continue;
+
+               if (cqr->status == DASD_CQR_TERMINATED) {
+                       base->discipline->handle_terminated_request(cqr);
+                       goto restart;
+               }
+
+               /*  Process requests that may be recovered */
+               if (cqr->status == DASD_CQR_NEED_ERP) {
+                       erp_fn = base->discipline->erp_action(cqr);
+                       erp_fn(cqr);
+                       goto restart;
+               }
+
+               /* log sense for fatal error */
+               if (cqr->status == DASD_CQR_FAILED) {
+                       dasd_log_sense(cqr, &cqr->irb);
+               }
+
+               /* First of all call extended error reporting. */
+               if (dasd_eer_enabled(base) &&
+                   cqr->status == DASD_CQR_FAILED) {
+                       dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
+
+                       /* restart request  */
+                       cqr->status = DASD_CQR_FILLED;
+                       cqr->retries = 255;
+                       spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
+                       dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
+                       spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
+                                              flags);
+                       goto restart;
+               }
+
+               /* Process finished ERP request. */
+               if (cqr->refers) {
+                       __dasd_process_erp(base, cqr);
+                       goto restart;
+               }
+
+               /* Rechain finished requests to final queue */
+               cqr->endclk = get_clock();
+               list_move_tail(&cqr->blocklist, final_queue);
+       }
+}
+
+static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
+{
+       dasd_schedule_block_bh(cqr->block);
+}
+
+static void __dasd_block_start_head(struct dasd_block *block)
+{
+       struct dasd_ccw_req *cqr;
+
+       if (list_empty(&block->ccw_queue))
+               return;
+       /* We allways begin with the first requests on the queue, as some
+        * of previously started requests have to be enqueued on a
+        * dasd_device again for error recovery.
+        */
+       list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
+               if (cqr->status != DASD_CQR_FILLED)
+                       continue;
+               /* Non-temporary stop condition will trigger fail fast */
+               if (block->base->stopped & ~DASD_STOPPED_PENDING &&
+                   test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
+                   (!dasd_eer_enabled(block->base))) {
+                       cqr->status = DASD_CQR_FAILED;
+                       dasd_schedule_block_bh(block);
+                       continue;
+               }
+               /* Don't try to start requests if device is stopped */
+               if (block->base->stopped)
+                       return;
+
+               /* just a fail safe check, should not happen */
+               if (!cqr->startdev)
+                       cqr->startdev = block->base;
+
+               /* make sure that the requests we submit find their way back */
+               cqr->callback = dasd_return_cqr_cb;
+
+               dasd_add_request_tail(cqr);
+       }
+}
+
+/*
+ * Central dasd_block layer routine. Takes requests from the generic
+ * block layer request queue, creates ccw requests, enqueues them on
+ * a dasd_device and processes ccw requests that have been returned.
+ */
+static void dasd_block_tasklet(struct dasd_block *block)
+{
+       struct list_head final_queue;
+       struct list_head *l, *n;
+       struct dasd_ccw_req *cqr;
+
+       atomic_set(&block->tasklet_scheduled, 0);
+       INIT_LIST_HEAD(&final_queue);
+       spin_lock(&block->queue_lock);
+       /* Finish off requests on ccw queue */
+       __dasd_process_block_ccw_queue(block, &final_queue);
+       spin_unlock(&block->queue_lock);
+       /* Now call the callback function of requests with final status */
+       spin_lock_irq(&block->request_queue_lock);
+       list_for_each_safe(l, n, &final_queue) {
+               cqr = list_entry(l, struct dasd_ccw_req, blocklist);
+               list_del_init(&cqr->blocklist);
+               __dasd_cleanup_cqr(cqr);
+       }
+       spin_lock(&block->queue_lock);
+       /* Get new request from the block device request queue */
+       __dasd_process_request_queue(block);
+       /* Now check if the head of the ccw queue needs to be started. */
+       __dasd_block_start_head(block);
+       spin_unlock(&block->queue_lock);
+       spin_unlock_irq(&block->request_queue_lock);
+       dasd_put_device(block->base);
+}
+
+static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
+{
+       wake_up(&dasd_flush_wq);
+}
+
+/*
+ * Go through all request on the dasd_block request queue, cancel them
+ * on the respective dasd_device, and return them to the generic
+ * block layer.
+ */
+static int dasd_flush_block_queue(struct dasd_block *block)
+{
+       struct dasd_ccw_req *cqr, *n;
+       int rc, i;
+       struct list_head flush_queue;
+
+       INIT_LIST_HEAD(&flush_queue);
+       spin_lock_bh(&block->queue_lock);
+       rc = 0;
+restart:
+       list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
+               /* if this request currently owned by a dasd_device cancel it */
+               if (cqr->status >= DASD_CQR_QUEUED)
+                       rc = dasd_cancel_req(cqr);
+               if (rc < 0)
+                       break;
+               /* Rechain request (including erp chain) so it won't be
+                * touched by the dasd_block_tasklet anymore.
+                * Replace the callback so we notice when the request
+                * is returned from the dasd_device layer.
+                */
+               cqr->callback = _dasd_wake_block_flush_cb;
+               for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
+                       list_move_tail(&cqr->blocklist, &flush_queue);
+               if (i > 1)
+                       /* moved more than one request - need to restart */
+                       goto restart;
+       }
+       spin_unlock_bh(&block->queue_lock);
+       /* Now call the callback function of flushed requests */
+restart_cb:
+       list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
+               wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
+               /* Process finished ERP request. */
+               if (cqr->refers) {
+                       spin_lock_bh(&block->queue_lock);
+                       __dasd_process_erp(block->base, cqr);
+                       spin_unlock_bh(&block->queue_lock);
+                       /* restart list_for_xx loop since dasd_process_erp
+                        * might remove multiple elements */
+                       goto restart_cb;
+               }
+               /* call the callback function */
+               spin_lock_irq(&block->request_queue_lock);
+               cqr->endclk = get_clock();
+               list_del_init(&cqr->blocklist);
+               __dasd_cleanup_cqr(cqr);
+               spin_unlock_irq(&block->request_queue_lock);
+       }
        return rc;
 }
 
 /*
- * SECTION: Block device operations (request queue, partitions, open, release).
+ * Schedules a call to dasd_tasklet over the device tasklet.
+ */
+void dasd_schedule_block_bh(struct dasd_block *block)
+{
+       /* Protect against rescheduling. */
+       if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
+               return;
+       /* life cycle of block is bound to it's base device */
+       dasd_get_device(block->base);
+       tasklet_hi_schedule(&block->tasklet);
+}
+
+
+/*
+ * SECTION: external block device operations
+ * (request queue handling, open, release, etc.)
  */
 
 /*
  * Dasd request queue function. Called from ll_rw_blk.c
  */
-static void
-do_dasd_request(request_queue_t * queue)
+static void do_dasd_request(struct request_queue *queue)
 {
-       struct dasd_device *device;
+       struct dasd_block *block;
 
-       device = (struct dasd_device *) queue->queuedata;
-       spin_lock(get_ccwdev_lock(device->cdev));
+       block = queue->queuedata;
+       spin_lock(&block->queue_lock);
        /* Get new request from the block device request queue */
-       __dasd_process_blk_queue(device);
+       __dasd_process_request_queue(block);
        /* Now check if the head of the ccw queue needs to be started. */
-       __dasd_start_head(device);
-       spin_unlock(get_ccwdev_lock(device->cdev));
+       __dasd_block_start_head(block);
+       spin_unlock(&block->queue_lock);
 }
 
 /*
  * Allocate and initialize request queue and default I/O scheduler.
  */
-static int
-dasd_alloc_queue(struct dasd_device * device)
+static int dasd_alloc_queue(struct dasd_block *block)
 {
        int rc;
 
-       device->request_queue = blk_init_queue(do_dasd_request,
-                                              &device->request_queue_lock);
-       if (device->request_queue == NULL)
+       block->request_queue = blk_init_queue(do_dasd_request,
+                                              &block->request_queue_lock);
+       if (block->request_queue == NULL)
                return -ENOMEM;
 
-       device->request_queue->queuedata = device;
+       block->request_queue->queuedata = block;
 
-       elevator_exit(device->request_queue->elevator);
-       rc = elevator_init(device->request_queue, "deadline");
+       elevator_exit(block->request_queue->elevator);
+       block->request_queue->elevator = NULL;
+       rc = elevator_init(block->request_queue, "deadline");
        if (rc) {
-               blk_cleanup_queue(device->request_queue);
+               blk_cleanup_queue(block->request_queue);
                return rc;
        }
        return 0;
@@ -1623,82 +2123,77 @@ dasd_alloc_queue(struct dasd_device * device)
 /*
  * Allocate and initialize request queue.
  */
-static void
-dasd_setup_queue(struct dasd_device * device)
+static void dasd_setup_queue(struct dasd_block *block)
 {
        int max;
 
-       blk_queue_hardsect_size(device->request_queue, device->bp_block);
-       max = device->discipline->max_blocks << device->s2b_shift;
-       blk_queue_max_sectors(device->request_queue, max);
-       blk_queue_max_phys_segments(device->request_queue, -1L);
-       blk_queue_max_hw_segments(device->request_queue, -1L);
-       blk_queue_max_segment_size(device->request_queue, -1L);
-       blk_queue_segment_boundary(device->request_queue, -1L);
-       blk_queue_ordered(device->request_queue, 1);
+       blk_queue_logical_block_size(block->request_queue, block->bp_block);
+       max = block->base->discipline->max_blocks << block->s2b_shift;
+       blk_queue_max_sectors(block->request_queue, max);
+       blk_queue_max_phys_segments(block->request_queue, -1L);
+       blk_queue_max_hw_segments(block->request_queue, -1L);
+       /* with page sized segments we can translate each segement into
+        * one idaw/tidaw
+        */
+       blk_queue_max_segment_size(block->request_queue, PAGE_SIZE);
+       blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1);
+       blk_queue_ordered(block->request_queue, QUEUE_ORDERED_DRAIN, NULL);
 }
 
 /*
  * Deactivate and free request queue.
  */
-static void
-dasd_free_queue(struct dasd_device * device)
+static void dasd_free_queue(struct dasd_block *block)
 {
-       if (device->request_queue) {
-               blk_cleanup_queue(device->request_queue);
-               device->request_queue = NULL;
+       if (block->request_queue) {
+               blk_cleanup_queue(block->request_queue);
+               block->request_queue = NULL;
        }
 }
 
 /*
  * Flush request on the request queue.
  */
-static void
-dasd_flush_request_queue(struct dasd_device * device)
+static void dasd_flush_request_queue(struct dasd_block *block)
 {
        struct request *req;
 
-       if (!device->request_queue)
+       if (!block->request_queue)
                return;
-       
-       spin_lock_irq(&device->request_queue_lock);
-       while (!list_empty(&device->request_queue->queue_head)) {
-               req = elv_next_request(device->request_queue);
-               if (req == NULL)
-                       break;
-               dasd_end_request(req, 0);
-               blkdev_dequeue_request(req);
-       }
-       spin_unlock_irq(&device->request_queue_lock);
+
+       spin_lock_irq(&block->request_queue_lock);
+       while ((req = blk_fetch_request(block->request_queue)))
+               __blk_end_request_all(req, -EIO);
+       spin_unlock_irq(&block->request_queue_lock);
 }
 
-static int
-dasd_open(struct inode *inp, struct file *filp)
+static int dasd_open(struct block_device *bdev, fmode_t mode)
 {
-       struct gendisk *disk = inp->i_bdev->bd_disk;
-       struct dasd_device *device = disk->private_data;
+       struct dasd_block *block = bdev->bd_disk->private_data;
+       struct dasd_device *base = block->base;
        int rc;
 
-        atomic_inc(&device->open_count);
-       if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+       atomic_inc(&block->open_count);
+       if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
                rc = -ENODEV;
                goto unlock;
        }
 
-       if (!try_module_get(device->discipline->owner)) {
+       if (!try_module_get(base->discipline->owner)) {
                rc = -EINVAL;
                goto unlock;
        }
 
        if (dasd_probeonly) {
-               DEV_MESSAGE(KERN_INFO, device, "%s",
-                           "No access to device due to probeonly mode");
+               dev_info(&base->cdev->dev,
+                        "Accessing the DASD failed because it is in "
+                        "probeonly mode\n");
                rc = -EPERM;
                goto out;
        }
 
-       if (device->state < DASD_STATE_BASIC) {
-               DBF_DEV_EVENT(DBF_ERR, device, " %s",
+       if (base->state <= DASD_STATE_BASIC) {
+               DBF_DEV_EVENT(DBF_ERR, base, " %s",
                              " Cannot open unrecognized device");
                rc = -ENODEV;
                goto out;
@@ -1707,31 +2202,56 @@ dasd_open(struct inode *inp, struct file *filp)
        return 0;
 
 out:
-       module_put(device->discipline->owner);
+       module_put(base->discipline->owner);
 unlock:
-       atomic_dec(&device->open_count);
+       atomic_dec(&block->open_count);
        return rc;
 }
 
-static int
-dasd_release(struct inode *inp, struct file *filp)
+static int dasd_release(struct gendisk *disk, fmode_t mode)
+{
+       struct dasd_block *block = disk->private_data;
+
+       atomic_dec(&block->open_count);
+       module_put(block->base->discipline->owner);
+       return 0;
+}
+
+/*
+ * Return disk geometry.
+ */
+static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 {
-       struct gendisk *disk = inp->i_bdev->bd_disk;
-       struct dasd_device *device = disk->private_data;
+       struct dasd_block *block;
+       struct dasd_device *base;
 
-       atomic_dec(&device->open_count);
-       module_put(device->discipline->owner);
+       block = bdev->bd_disk->private_data;
+       if (!block)
+               return -ENODEV;
+       base = block->base;
+
+       if (!base->discipline ||
+           !base->discipline->fill_geometry)
+               return -EINVAL;
+
+       base->discipline->fill_geometry(block, geo);
+       geo->start = get_start_sect(bdev) >> block->s2b_shift;
        return 0;
 }
 
-struct block_device_operations
+const struct block_device_operations
 dasd_device_operations = {
        .owner          = THIS_MODULE,
        .open           = dasd_open,
        .release        = dasd_release,
        .ioctl          = dasd_ioctl,
+       .compat_ioctl   = dasd_ioctl,
+       .getgeo         = dasd_getgeo,
 };
 
+/*******************************************************************************
+ * end of block device operations
+ */
 
 static void
 dasd_exit(void)
@@ -1739,10 +2259,13 @@ dasd_exit(void)
 #ifdef CONFIG_PROC_FS
        dasd_proc_exit();
 #endif
-       dasd_ioctl_exit();
+       dasd_eer_exit();
+        if (dasd_page_cache != NULL) {
+               kmem_cache_destroy(dasd_page_cache);
+               dasd_page_cache = NULL;
+       }
        dasd_gendisk_exit();
        dasd_devmap_exit();
-       devfs_remove("dasd");
        if (dasd_debug_area != NULL) {
                debug_unregister(dasd_debug_area);
                dasd_debug_area = NULL;
@@ -1753,32 +2276,59 @@ dasd_exit(void)
  * SECTION: common functions for ccw_driver use
  */
 
-/* initial attempt at a probe function. this can be simplified once
- * the other detection code is gone */
-int
-dasd_generic_probe (struct ccw_device *cdev,
-                   struct dasd_discipline *discipline)
+static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
+{
+       struct ccw_device *cdev = data;
+       int ret;
+
+       ret = ccw_device_set_online(cdev);
+       if (ret)
+               pr_warning("%s: Setting the DASD online failed with rc=%d\n",
+                          dev_name(&cdev->dev), ret);
+       else {
+               struct dasd_device *device = dasd_device_from_cdev(cdev);
+               wait_event(dasd_init_waitq, _wait_for_device(device));
+               dasd_put_device(device);
+       }
+}
+
+/*
+ * Initial attempt at a probe function. this can be simplified once
+ * the other detection code is gone.
+ */
+int dasd_generic_probe(struct ccw_device *cdev,
+                      struct dasd_discipline *discipline)
 {
        int ret;
 
        ret = dasd_add_sysfs_files(cdev);
        if (ret) {
-               printk(KERN_WARNING
-                      "dasd_generic_probe: could not add sysfs entries "
-                      "for %s\n", cdev->dev.bus_id);
-       } else {
-               cdev->handler = &dasd_int_handler;
+               DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
+                               "dasd_generic_probe: could not add "
+                               "sysfs entries");
+               return ret;
        }
+       cdev->handler = &dasd_int_handler;
 
-       return ret;
+       /*
+        * Automatically online either all dasd devices (dasd_autodetect)
+        * or all devices specified with dasd= parameters during
+        * initial probe.
+        */
+       if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
+           (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
+               async_schedule(dasd_generic_auto_online, cdev);
+       return 0;
 }
 
-/* this will one day be called from a global not_oper handler.
- * It is also used by driver_unregister during module unload */
-void
-dasd_generic_remove (struct ccw_device *cdev)
+/*
+ * This will one day be called from a global not_oper handler.
+ * It is also used by driver_unregister during module unload.
+ */
+void dasd_generic_remove(struct ccw_device *cdev)
 {
        struct dasd_device *device;
+       struct dasd_block *block;
 
        cdev->handler = NULL;
 
@@ -1798,77 +2348,91 @@ dasd_generic_remove (struct ccw_device *cdev)
         */
        dasd_set_target_state(device, DASD_STATE_NEW);
        /* dasd_delete_device destroys the device reference. */
+       block = device->block;
+       device->block = NULL;
        dasd_delete_device(device);
+       /*
+        * life cycle of block is bound to device, so delete it after
+        * device was safely removed
+        */
+       if (block)
+               dasd_free_block(block);
 }
 
-/* activate a device. This is called from dasd_{eckd,fba}_probe() when either
+/*
+ * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
  * the device is detected for the first time and is supposed to be used
- * or the user has started activation through sysfs */
-int
-dasd_generic_set_online (struct ccw_device *cdev,
-                        struct dasd_discipline *discipline)
-
+ * or the user has started activation through sysfs.
+ */
+int dasd_generic_set_online(struct ccw_device *cdev,
+                           struct dasd_discipline *base_discipline)
 {
+       struct dasd_discipline *discipline;
        struct dasd_device *device;
-       int feature_diag, rc;
+       int rc;
 
+       /* first online clears initial online feature flag */
+       dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
        device = dasd_create_device(cdev);
        if (IS_ERR(device))
                return PTR_ERR(device);
 
-       feature_diag = dasd_get_feature(cdev, DASD_FEATURE_USEDIAG);
-       if (feature_diag < 0)
-               return feature_diag;
-
-       if (feature_diag) {
+       discipline = base_discipline;
+       if (device->features & DASD_FEATURE_USEDIAG) {
                if (!dasd_diag_discipline_pointer) {
-                       printk (KERN_WARNING
-                               "dasd_generic couldn't online device %s "
-                               "- discipline DIAG not available\n",
-                               cdev->dev.bus_id);
+                       pr_warning("%s Setting the DASD online failed because "
+                                  "of missing DIAG discipline\n",
+                                  dev_name(&cdev->dev));
                        dasd_delete_device(device);
                        return -ENODEV;
                }
                discipline = dasd_diag_discipline_pointer;
        }
+       if (!try_module_get(base_discipline->owner)) {
+               dasd_delete_device(device);
+               return -EINVAL;
+       }
+       if (!try_module_get(discipline->owner)) {
+               module_put(base_discipline->owner);
+               dasd_delete_device(device);
+               return -EINVAL;
+       }
+       device->base_discipline = base_discipline;
        device->discipline = discipline;
 
+       /* check_device will allocate block device if necessary */
        rc = discipline->check_device(device);
        if (rc) {
-               printk (KERN_WARNING
-                       "dasd_generic couldn't online device %s "
-                       "with discipline %s rc=%i\n",
-                       cdev->dev.bus_id, discipline->name, rc);
+               pr_warning("%s Setting the DASD online with discipline %s "
+                          "failed with rc=%i\n",
+                          dev_name(&cdev->dev), discipline->name, rc);
+               module_put(discipline->owner);
+               module_put(base_discipline->owner);
                dasd_delete_device(device);
                return rc;
        }
 
        dasd_set_target_state(device, DASD_STATE_ONLINE);
        if (device->state <= DASD_STATE_KNOWN) {
-               printk (KERN_WARNING
-                       "dasd_generic discipline not found for %s\n",
-                       cdev->dev.bus_id);
+               pr_warning("%s Setting the DASD online failed because of a "
+                          "missing discipline\n", dev_name(&cdev->dev));
                rc = -ENODEV;
                dasd_set_target_state(device, DASD_STATE_NEW);
+               if (device->block)
+                       dasd_free_block(device->block);
                dasd_delete_device(device);
        } else
                pr_debug("dasd_generic device %s found\n",
-                               cdev->dev.bus_id);
-
-       /* FIXME: we have to wait for the root device but we don't want
-        * to wait for each single device but for all at once. */
-       wait_event(dasd_init_waitq, _wait_for_device(device));
-
+                               dev_name(&cdev->dev));
        dasd_put_device(device);
-
        return rc;
 }
 
-int
-dasd_generic_set_offline (struct ccw_device *cdev)
+int dasd_generic_set_offline(struct ccw_device *cdev)
 {
        struct dasd_device *device;
-       int max_count;
+       struct dasd_block *block;
+       int max_count, open_count;
 
        device = dasd_device_from_cdev(cdev);
        if (IS_ERR(device))
@@ -1884,118 +2448,288 @@ dasd_generic_set_offline (struct ccw_device *cdev)
         * the blkdev_get in dasd_scan_partitions. We are only interested
         * in the other openers.
         */
-       max_count = device->bdev ? 0 : -1;
-       if (atomic_read(&device->open_count) > max_count) {
-               printk (KERN_WARNING "Can't offline dasd device with open"
-                       " count = %i.\n",
-                       atomic_read(&device->open_count));
-               clear_bit(DASD_FLAG_OFFLINE, &device->flags);
-               dasd_put_device(device);
-               return -EBUSY;
+       if (device->block) {
+               max_count = device->block->bdev ? 0 : -1;
+               open_count = atomic_read(&device->block->open_count);
+               if (open_count > max_count) {
+                       if (open_count > 0)
+                               pr_warning("%s: The DASD cannot be set offline "
+                                          "with open count %i\n",
+                                          dev_name(&cdev->dev), open_count);
+                       else
+                               pr_warning("%s: The DASD cannot be set offline "
+                                          "while it is in use\n",
+                                          dev_name(&cdev->dev));
+                       clear_bit(DASD_FLAG_OFFLINE, &device->flags);
+                       dasd_put_device(device);
+                       return -EBUSY;
+               }
        }
        dasd_set_target_state(device, DASD_STATE_NEW);
        /* dasd_delete_device destroys the device reference. */
+       block = device->block;
+       device->block = NULL;
        dasd_delete_device(device);
-
+       /*
+        * life cycle of block is bound to device, so delete it after
+        * device was safely removed
+        */
+       if (block)
+               dasd_free_block(block);
        return 0;
 }
 
-int
-dasd_generic_notify(struct ccw_device *cdev, int event)
+int dasd_generic_notify(struct ccw_device *cdev, int event)
 {
        struct dasd_device *device;
        struct dasd_ccw_req *cqr;
-       unsigned long flags;
        int ret;
 
-       device = dasd_device_from_cdev(cdev);
+       device = dasd_device_from_cdev_locked(cdev);
        if (IS_ERR(device))
                return 0;
-       spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
        ret = 0;
        switch (event) {
        case CIO_GONE:
+       case CIO_BOXED:
        case CIO_NO_PATH:
+               /* First of all call extended error reporting. */
+               dasd_eer_write(device, NULL, DASD_EER_NOPATH);
+
                if (device->state < DASD_STATE_BASIC)
                        break;
                /* Device is active. We want to keep it. */
-               if (test_bit(DASD_FLAG_DSC_ERROR, &device->flags)) {
-                       list_for_each_entry(cqr, &device->ccw_queue, list)
-                               if (cqr->status == DASD_CQR_IN_IO)
-                                       cqr->status = DASD_CQR_FAILED;
-                       device->stopped |= DASD_STOPPED_DC_EIO;
-                       dasd_schedule_bh(device);
-               } else {
-                       list_for_each_entry(cqr, &device->ccw_queue, list)
-                               if (cqr->status == DASD_CQR_IN_IO) {
-                                       cqr->status = DASD_CQR_QUEUED;
-                                       cqr->retries++;
-                               }
-                       device->stopped |= DASD_STOPPED_DC_WAIT;
-                       dasd_set_timer(device, 0);
-               }
+               list_for_each_entry(cqr, &device->ccw_queue, devlist)
+                       if (cqr->status == DASD_CQR_IN_IO) {
+                               cqr->status = DASD_CQR_QUEUED;
+                               cqr->retries++;
+                       }
+               dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
+               dasd_device_clear_timer(device);
+               dasd_schedule_device_bh(device);
                ret = 1;
                break;
        case CIO_OPER:
                /* FIXME: add a sanity check. */
-               device->stopped &= ~(DASD_STOPPED_DC_WAIT|DASD_STOPPED_DC_EIO);
-               dasd_schedule_bh(device);
+               dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
+               if (device->stopped & DASD_UNRESUMED_PM) {
+                       dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
+                       dasd_restore_device(device);
+                       ret = 1;
+                       break;
+               }
+               dasd_schedule_device_bh(device);
+               if (device->block)
+                       dasd_schedule_block_bh(device->block);
                ret = 1;
                break;
        }
-       spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
        dasd_put_device(device);
        return ret;
 }
 
-/*
- * Automatically online either all dasd devices (dasd_autodetect) or
- * all devices specified with dasd= parameters.
- */
-static int
-__dasd_auto_online(struct device *dev, void *data)
+int dasd_generic_pm_freeze(struct ccw_device *cdev)
+{
+       struct dasd_ccw_req *cqr, *n;
+       int rc;
+       struct list_head freeze_queue;
+       struct dasd_device *device = dasd_device_from_cdev(cdev);
+
+       if (IS_ERR(device))
+               return PTR_ERR(device);
+       /* disallow new I/O  */
+       dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
+       /* clear active requests */
+       INIT_LIST_HEAD(&freeze_queue);
+       spin_lock_irq(get_ccwdev_lock(cdev));
+       rc = 0;
+       list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
+               /* Check status and move request to flush_queue */
+               if (cqr->status == DASD_CQR_IN_IO) {
+                       rc = device->discipline->term_IO(cqr);
+                       if (rc) {
+                               /* unable to terminate requeust */
+                               dev_err(&device->cdev->dev,
+                                       "Unable to terminate request %p "
+                                       "on suspend\n", cqr);
+                               spin_unlock_irq(get_ccwdev_lock(cdev));
+                               dasd_put_device(device);
+                               return rc;
+                       }
+               }
+               list_move_tail(&cqr->devlist, &freeze_queue);
+       }
+
+       spin_unlock_irq(get_ccwdev_lock(cdev));
+
+       list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
+               wait_event(dasd_flush_wq,
+                          (cqr->status != DASD_CQR_CLEAR_PENDING));
+               if (cqr->status == DASD_CQR_CLEARED)
+                       cqr->status = DASD_CQR_QUEUED;
+       }
+       /* move freeze_queue to start of the ccw_queue */
+       spin_lock_irq(get_ccwdev_lock(cdev));
+       list_splice_tail(&freeze_queue, &device->ccw_queue);
+       spin_unlock_irq(get_ccwdev_lock(cdev));
+
+       if (device->discipline->freeze)
+               rc = device->discipline->freeze(device);
+
+       dasd_put_device(device);
+       return rc;
+}
+EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
+
+int dasd_generic_restore_device(struct ccw_device *cdev)
 {
-       struct ccw_device *cdev;
+       struct dasd_device *device = dasd_device_from_cdev(cdev);
+       int rc = 0;
+
+       if (IS_ERR(device))
+               return PTR_ERR(device);
+
+       /* allow new IO again */
+       dasd_device_remove_stop_bits(device,
+                                    (DASD_STOPPED_PM | DASD_UNRESUMED_PM));
+
+       dasd_schedule_device_bh(device);
+
+       /*
+        * call discipline restore function
+        * if device is stopped do nothing e.g. for disconnected devices
+        */
+       if (device->discipline->restore && !(device->stopped))
+               rc = device->discipline->restore(device);
+       if (rc || device->stopped)
+               /*
+                * if the resume failed for the DASD we put it in
+                * an UNRESUMED stop state
+                */
+               device->stopped |= DASD_UNRESUMED_PM;
+
+       if (device->block)
+               dasd_schedule_block_bh(device->block);
 
-       cdev = to_ccwdev(dev);
-       if (dasd_autodetect || dasd_busid_known(cdev->dev.bus_id) == 0)
-               ccw_device_set_online(cdev);
+       dasd_put_device(device);
        return 0;
 }
+EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
 
-void
-dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
+static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
+                                                  void *rdc_buffer,
+                                                  int rdc_buffer_size,
+                                                  int magic)
 {
-       struct device_driver *drv;
+       struct dasd_ccw_req *cqr;
+       struct ccw1 *ccw;
+       unsigned long *idaw;
 
-       drv = get_driver(&dasd_discipline_driver->driver);
-       driver_for_each_device(drv, NULL, NULL, __dasd_auto_online);
-       put_driver(drv);
+       cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
+
+       if (IS_ERR(cqr)) {
+               /* internal error 13 - Allocating the RDC request failed*/
+               dev_err(&device->cdev->dev,
+                        "An error occurred in the DASD device driver, "
+                        "reason=%s\n", "13");
+               return cqr;
+       }
+
+       ccw = cqr->cpaddr;
+       ccw->cmd_code = CCW_CMD_RDC;
+       if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
+               idaw = (unsigned long *) (cqr->data);
+               ccw->cda = (__u32)(addr_t) idaw;
+               ccw->flags = CCW_FLAG_IDA;
+               idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
+       } else {
+               ccw->cda = (__u32)(addr_t) rdc_buffer;
+               ccw->flags = 0;
+       }
+
+       ccw->count = rdc_buffer_size;
+       cqr->startdev = device;
+       cqr->memdev = device;
+       cqr->expires = 10*HZ;
+       cqr->retries = 256;
+       cqr->buildclk = get_clock();
+       cqr->status = DASD_CQR_FILLED;
+       return cqr;
 }
 
-static int __init
-dasd_init(void)
+
+int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
+                               void *rdc_buffer, int rdc_buffer_size)
+{
+       int ret;
+       struct dasd_ccw_req *cqr;
+
+       cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
+                                    magic);
+       if (IS_ERR(cqr))
+               return PTR_ERR(cqr);
+
+       ret = dasd_sleep_on(cqr);
+       dasd_sfree_request(cqr, cqr->memdev);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
+
+/*
+ *   In command mode and transport mode we need to look for sense
+ *   data in different places. The sense data itself is allways
+ *   an array of 32 bytes, so we can unify the sense data access
+ *   for both modes.
+ */
+char *dasd_get_sense(struct irb *irb)
+{
+       struct tsb *tsb = NULL;
+       char *sense = NULL;
+
+       if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
+               if (irb->scsw.tm.tcw)
+                       tsb = tcw_get_tsb((struct tcw *)(unsigned long)
+                                         irb->scsw.tm.tcw);
+               if (tsb && tsb->length == 64 && tsb->flags)
+                       switch (tsb->flags & 0x07) {
+                       case 1: /* tsa_iostat */
+                               sense = tsb->tsa.iostat.sense;
+                               break;
+                       case 2: /* tsa_ddpc */
+                               sense = tsb->tsa.ddpc.sense;
+                               break;
+                       default:
+                               /* currently we don't use interrogate data */
+                               break;
+                       }
+       } else if (irb->esw.esw0.erw.cons) {
+               sense = irb->ecw;
+       }
+       return sense;
+}
+EXPORT_SYMBOL_GPL(dasd_get_sense);
+
+static int __init dasd_init(void)
 {
        int rc;
 
        init_waitqueue_head(&dasd_init_waitq);
+       init_waitqueue_head(&dasd_flush_wq);
+       init_waitqueue_head(&generic_waitq);
 
        /* register 'common' DASD debug area, used for all DBF_XXX calls */
-       dasd_debug_area = debug_register("dasd", 1, 2, 8 * sizeof (long));
+       dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
        if (dasd_debug_area == NULL) {
                rc = -ENOMEM;
                goto failed;
        }
        debug_register_view(dasd_debug_area, &debug_sprintf_view);
-       debug_set_level(dasd_debug_area, DBF_EMERG);
+       debug_set_level(dasd_debug_area, DBF_WARNING);
 
        DBF_EVENT(DBF_EMERG, "%s", "debug area created");
 
        dasd_diag_discipline_pointer = NULL;
 
-       rc = devfs_mk_dir("dasd");
-       if (rc)
-               goto failed;
        rc = dasd_devmap_init();
        if (rc)
                goto failed;
@@ -2005,7 +2739,7 @@ dasd_init(void)
        rc = dasd_parse();
        if (rc)
                goto failed;
-       rc = dasd_ioctl_init();
+       rc = dasd_eer_init();
        if (rc)
                goto failed;
 #ifdef CONFIG_PROC_FS
@@ -2016,7 +2750,7 @@ dasd_init(void)
 
        return 0;
 failed:
-       MESSAGE(KERN_INFO, "%s", "initialization not performed due to errors");
+       pr_info("The DASD device driver could not be initialized\n");
        dasd_exit();
        return rc;
 }
@@ -2030,15 +2764,18 @@ EXPORT_SYMBOL(dasd_diag_discipline_pointer);
 EXPORT_SYMBOL(dasd_add_request_head);
 EXPORT_SYMBOL(dasd_add_request_tail);
 EXPORT_SYMBOL(dasd_cancel_req);
-EXPORT_SYMBOL(dasd_clear_timer);
+EXPORT_SYMBOL(dasd_device_clear_timer);
+EXPORT_SYMBOL(dasd_block_clear_timer);
 EXPORT_SYMBOL(dasd_enable_device);
 EXPORT_SYMBOL(dasd_int_handler);
 EXPORT_SYMBOL(dasd_kfree_request);
 EXPORT_SYMBOL(dasd_kick_device);
 EXPORT_SYMBOL(dasd_kmalloc_request);
-EXPORT_SYMBOL(dasd_schedule_bh);
+EXPORT_SYMBOL(dasd_schedule_device_bh);
+EXPORT_SYMBOL(dasd_schedule_block_bh);
 EXPORT_SYMBOL(dasd_set_target_state);
-EXPORT_SYMBOL(dasd_set_timer);
+EXPORT_SYMBOL(dasd_device_set_timer);
+EXPORT_SYMBOL(dasd_block_set_timer);
 EXPORT_SYMBOL(dasd_sfree_request);
 EXPORT_SYMBOL(dasd_sleep_on);
 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
@@ -2052,23 +2789,7 @@ EXPORT_SYMBOL_GPL(dasd_generic_remove);
 EXPORT_SYMBOL_GPL(dasd_generic_notify);
 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
-EXPORT_SYMBOL_GPL(dasd_generic_auto_online);
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: 1
- * tab-width: 8
- * End:
- */
+EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
+EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
+EXPORT_SYMBOL_GPL(dasd_alloc_block);
+EXPORT_SYMBOL_GPL(dasd_free_block);