Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2497 insertions, 0 deletions

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
new file mode 100644
index 000000000..b2a4c3433
--- /dev/null
+++ b/drivers/s390/block/dasd_devmap.c
@@ -0,0 +1,2497 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
+ *		    Horst Hummel <Horst.Hummel@de.ibm.com>
+ *		    Carsten Otte <Cotte@de.ibm.com>
+ *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Bugreports.to..: <Linux390@de.ibm.com>
+ * Copyright IBM Corp. 1999,2001
+ *
+ * Device mapping and dasd= parameter parsing functions. All devmap
+ * functions may not be called from interrupt context. In particular
+ * dasd_get_device is a no-no from interrupt context.
+ *
+ */
+
+#define KMSG_COMPONENT "dasd"
+
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <asm/debug.h>
+#include <linux/uaccess.h>
+#include <asm/ipl.h>
+
+/* This is ugly... */
+#define PRINTK_HEADER "dasd_devmap:"
+#define DASD_MAX_PARAMS 256
+
+#include "dasd_int.h"
+
+struct kmem_cache *dasd_page_cache;
+EXPORT_SYMBOL_GPL(dasd_page_cache);
+
+/*
+ * dasd_devmap_t is used to store the features and the relation
+ * between device number and device index. To find a dasd_devmap_t
+ * that corresponds to a device number of a device index each
+ * dasd_devmap_t is added to two linked lists, one to search by
+ * the device number and one to search by the device index. As
+ * soon as big minor numbers are available the device index list
+ * can be removed since the device number will then be identical
+ * to the device index.
+ */
+struct dasd_devmap {
+	struct list_head list;
+	char bus_id[DASD_BUS_ID_SIZE];
+        unsigned int devindex;
+        unsigned short features;
+	struct dasd_device *device;
+	struct dasd_copy_relation *copy;
+};
+
+/*
+ * Parameter parsing functions for dasd= parameter. The syntax is:
+ *   <devno>		: (0x)?[0-9a-fA-F]+
+ *   <busid>		: [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
+ *   <feature>		: ro
+ *   <feature_list>	: \(<feature>(:<feature>)*\)
+ *   <devno-range>	: <devno>(-<devno>)?<feature_list>?
+ *   <busid-range>	: <busid>(-<busid>)?<feature_list>?
+ *   <devices>		: <devno-range>|<busid-range>
+ *   <dasd_module>	: dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
+ *
+ *   <dasd>		: autodetect|probeonly|<devices>(,<devices>)*
+ */
+
+int dasd_probeonly =  0;	/* is true, when probeonly mode is active */
+int dasd_autodetect = 0;	/* is true, when autodetection is active */
+int dasd_nopav = 0;		/* is true, when PAV is disabled */
+EXPORT_SYMBOL_GPL(dasd_nopav);
+int dasd_nofcx;			/* disable High Performance Ficon */
+EXPORT_SYMBOL_GPL(dasd_nofcx);
+
+/*
+ * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
+ * it is named 'dasd' to directly be filled by insmod with the comma separated
+ * strings when running as a module.
+ */
+static char *dasd[DASD_MAX_PARAMS];
+module_param_array(dasd, charp, NULL, S_IRUGO);
+
+/*
+ * Single spinlock to protect devmap and servermap structures and lists.
+ */
+static DEFINE_SPINLOCK(dasd_devmap_lock);
+
+/*
+ * Hash lists for devmap structures.
+ */
+static struct list_head dasd_hashlists[256];
+int dasd_max_devindex;
+
+static struct dasd_devmap *dasd_add_busid(const char *, int);
+
+static inline int
+dasd_hash_busid(const char *bus_id)
+{
+	int hash, i;
+
+	hash = 0;
+	for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
+		hash += *bus_id;
+	return hash & 0xff;
+}
+
+#ifndef MODULE
+static int __init dasd_call_setup(char *opt)
+{
+	static int i __initdata;
+	char *tmp;
+
+	while (i < DASD_MAX_PARAMS) {
+		tmp = strsep(&opt, ",");
+		if (!tmp)
+			break;
+
+		dasd[i++] = tmp;
+	}
+
+	return 1;
+}
+
+__setup ("dasd=", dasd_call_setup);
+#endif	/* #ifndef MODULE */
+
+#define	DASD_IPLDEV	"ipldev"
+
+/*
+ * Read a device busid/devno from a string.
+ */
+static int dasd_busid(char *str, int *id0, int *id1, int *devno)
+{
+	unsigned int val;
+	char *tok;
+
+	/* Interpret ipldev busid */
+	if (strncmp(DASD_IPLDEV, str, strlen(DASD_IPLDEV)) == 0) {
+		if (ipl_info.type != IPL_TYPE_CCW) {
+			pr_err("The IPL device is not a CCW device\n");
+			return -EINVAL;
+		}
+		*id0 = 0;
+		*id1 = ipl_info.data.ccw.dev_id.ssid;
+		*devno = ipl_info.data.ccw.dev_id.devno;
+
+		return 0;
+	}
+
+	/* Old style 0xXXXX or XXXX */
+	if (!kstrtouint(str, 16, &val)) {
+		*id0 = *id1 = 0;
+		if (val > 0xffff)
+			return -EINVAL;
+		*devno = val;
+		return 0;
+	}
+
+	/* New style x.y.z busid */
+	tok = strsep(&str, ".");
+	if (kstrtouint(tok, 16, &val) || val > 0xff)
+		return -EINVAL;
+	*id0 = val;
+
+	tok = strsep(&str, ".");
+	if (kstrtouint(tok, 16, &val) || val > 0xff)
+		return -EINVAL;
+	*id1 = val;
+
+	tok = strsep(&str, ".");
+	if (kstrtouint(tok, 16, &val) || val > 0xffff)
+		return -EINVAL;
+	*devno = val;
+
+	return 0;
+}
+
+/*
+ * Read colon separated list of dasd features.
+ */
+static int __init dasd_feature_list(char *str)
+{
+	int features, len, rc;
+
+	features = 0;
+	rc = 0;
+
+	if (!str)
+		return DASD_FEATURE_DEFAULT;
+
+	while (1) {
+		for (len = 0;
+		     str[len] && str[len] != ':' && str[len] != ')'; len++);
+		if (len == 2 && !strncmp(str, "ro", 2))
+			features |= DASD_FEATURE_READONLY;
+		else if (len == 4 && !strncmp(str, "diag", 4))
+			features |= DASD_FEATURE_USEDIAG;
+		else if (len == 3 && !strncmp(str, "raw", 3))
+			features |= DASD_FEATURE_USERAW;
+		else if (len == 6 && !strncmp(str, "erplog", 6))
+			features |= DASD_FEATURE_ERPLOG;
+		else if (len == 8 && !strncmp(str, "failfast", 8))
+			features |= DASD_FEATURE_FAILFAST;
+		else {
+			pr_warn("%.*s is not a supported device option\n",
+				len, str);
+			rc = -EINVAL;
+		}
+		str += len;
+		if (*str != ':')
+			break;
+		str++;
+	}
+
+	return rc ? : features;
+}
+
+/*
+ * Try to match the first element on the comma separated parse string
+ * with one of the known keywords. If a keyword is found, take the approprate
+ * action and return a pointer to the residual string. If the first element
+ * could not be matched to any keyword then return an error code.
+ */
+static int __init dasd_parse_keyword(char *keyword)
+{
+	int length = strlen(keyword);
+
+	if (strncmp("autodetect", keyword, length) == 0) {
+		dasd_autodetect = 1;
+		pr_info("The autodetection mode has been activated\n");
+		return 0;
+        }
+	if (strncmp("probeonly", keyword, length) == 0) {
+		dasd_probeonly = 1;
+		pr_info("The probeonly mode has been activated\n");
+		return 0;
+        }
+	if (strncmp("nopav", keyword, length) == 0) {
+		if (MACHINE_IS_VM)
+			pr_info("'nopav' is not supported on z/VM\n");
+		else {
+			dasd_nopav = 1;
+			pr_info("PAV support has be deactivated\n");
+		}
+		return 0;
+	}
+	if (strncmp("nofcx", keyword, length) == 0) {
+		dasd_nofcx = 1;
+		pr_info("High Performance FICON support has been "
+			"deactivated\n");
+		return 0;
+	}
+	if (strncmp("fixedbuffers", keyword, length) == 0) {
+		if (dasd_page_cache)
+			return 0;
+		dasd_page_cache =
+			kmem_cache_create("dasd_page_cache", PAGE_SIZE,
+					  PAGE_SIZE, SLAB_CACHE_DMA,
+					  NULL);
+		if (!dasd_page_cache)
+			DBF_EVENT(DBF_WARNING, "%s", "Failed to create slab, "
+				"fixed buffer mode disabled.");
+		else
+			DBF_EVENT(DBF_INFO, "%s",
+				 "turning on fixed buffer mode");
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+/*
+ * Split a string of a device range into its pieces and return the from, to, and
+ * feature parts separately.
+ * e.g.:
+ * 0.0.1234-0.0.5678(ro:erplog) -> from: 0.0.1234 to: 0.0.5678 features: ro:erplog
+ * 0.0.8765(raw) -> from: 0.0.8765 to: null features: raw
+ * 0x4321 -> from: 0x4321 to: null features: null
+ */
+static int __init dasd_evaluate_range_param(char *range, char **from_str,
+					    char **to_str, char **features_str)
+{
+	int rc = 0;
+
+	/* Do we have a range or a single device? */
+	if (strchr(range, '-')) {
+		*from_str = strsep(&range, "-");
+		*to_str = strsep(&range, "(");
+		*features_str = strsep(&range, ")");
+	} else {
+		*from_str = strsep(&range, "(");
+		*features_str = strsep(&range, ")");
+	}
+
+	if (*features_str && !range) {
+		pr_warn("A closing parenthesis ')' is missing in the dasd= parameter\n");
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+/*
+ * Try to interprete the range string as a device number or a range of devices.
+ * If the interpretation is successful, create the matching dasd_devmap entries.
+ * If interpretation fails or in case of an error, return an error code.
+ */
+static int __init dasd_parse_range(const char *range)
+{
+	struct dasd_devmap *devmap;
+	int from, from_id0, from_id1;
+	int to, to_id0, to_id1;
+	int features;
+	char bus_id[DASD_BUS_ID_SIZE + 1];
+	char *features_str = NULL;
+	char *from_str = NULL;
+	char *to_str = NULL;
+	int rc = 0;
+	char *tmp;
+
+	tmp = kstrdup(range, GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
+
+	if (dasd_evaluate_range_param(tmp, &from_str, &to_str, &features_str)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (dasd_busid(from_str, &from_id0, &from_id1, &from)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	to = from;
+	to_id0 = from_id0;
+	to_id1 = from_id1;
+	if (to_str) {
+		if (dasd_busid(to_str, &to_id0, &to_id1, &to)) {
+			rc = -EINVAL;
+			goto out;
+		}
+		if (from_id0 != to_id0 || from_id1 != to_id1 || from > to) {
+			pr_err("%s is not a valid device range\n", range);
+			rc = -EINVAL;
+			goto out;
+		}
+	}
+
+	features = dasd_feature_list(features_str);
+	if (features < 0) {
+		rc = -EINVAL;
+		goto out;
+	}
+	/* each device in dasd= parameter should be set initially online */
+	features |= DASD_FEATURE_INITIAL_ONLINE;
+	while (from <= to) {
+		sprintf(bus_id, "%01x.%01x.%04x", from_id0, from_id1, from++);
+		devmap = dasd_add_busid(bus_id, features);
+		if (IS_ERR(devmap)) {
+			rc = PTR_ERR(devmap);
+			goto out;
+		}
+	}
+
+out:
+	kfree(tmp);
+
+	return rc;
+}
+
+/*
+ * Parse parameters stored in dasd[]
+ * The 'dasd=...' parameter allows to specify a comma separated list of
+ * keywords and device ranges. The parameters in that list will be stored as
+ * separate elementes in dasd[].
+ */
+int __init dasd_parse(void)
+{
+	int rc, i;
+	char *cur;
+
+	rc = 0;
+	for (i = 0; i < DASD_MAX_PARAMS; i++) {
+		cur = dasd[i];
+		if (!cur)
+			break;
+		if (*cur == '\0')
+			continue;
+
+		rc = dasd_parse_keyword(cur);
+		if (rc)
+			rc = dasd_parse_range(cur);
+
+		if (rc)
+			break;
+	}
+
+	return rc;
+}
+
+/*
+ * Add a devmap for the device specified by busid. It is possible that
+ * the devmap already exists (dasd= parameter). The order of the devices
+ * added through this function will define the kdevs for the individual
+ * devices.
+ */
+static struct dasd_devmap *
+dasd_add_busid(const char *bus_id, int features)
+{
+	struct dasd_devmap *devmap, *new, *tmp;
+	int hash;
+
+	new = kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
+	if (!new)
+		return ERR_PTR(-ENOMEM);
+	spin_lock(&dasd_devmap_lock);
+	devmap = NULL;
+	hash = dasd_hash_busid(bus_id);
+	list_for_each_entry(tmp, &dasd_hashlists[hash], list)
+		if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
+			devmap = tmp;
+			break;
+		}
+	if (!devmap) {
+		/* This bus_id is new. */
+		new->devindex = dasd_max_devindex++;
+		strscpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
+		new->features = features;
+		new->device = NULL;
+		list_add(&new->list, &dasd_hashlists[hash]);
+		devmap = new;
+		new = NULL;
+	}
+	spin_unlock(&dasd_devmap_lock);
+	kfree(new);
+	return devmap;
+}
+
+static struct dasd_devmap *
+dasd_find_busid_locked(const char *bus_id)
+{
+	struct dasd_devmap *devmap, *tmp;
+	int hash;
+
+	devmap = ERR_PTR(-ENODEV);
+	hash = dasd_hash_busid(bus_id);
+	list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
+		if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
+			devmap = tmp;
+			break;
+		}
+	}
+	return devmap;
+}
+
+/*
+ * Find devmap for device with given bus_id.
+ */
+static struct dasd_devmap *
+dasd_find_busid(const char *bus_id)
+{
+	struct dasd_devmap *devmap;
+
+	spin_lock(&dasd_devmap_lock);
+	devmap = dasd_find_busid_locked(bus_id);
+	spin_unlock(&dasd_devmap_lock);
+	return devmap;
+}
+
+/*
+ * Check if busid has been added to the list of dasd ranges.
+ */
+int
+dasd_busid_known(const char *bus_id)
+{
+	return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
+}
+
+/*
+ * Forget all about the device numbers added so far.
+ * This may only be called at module unload or system shutdown.
+ */
+static void
+dasd_forget_ranges(void)
+{
+	struct dasd_devmap *devmap, *n;
+	int i;
+
+	spin_lock(&dasd_devmap_lock);
+	for (i = 0; i < 256; i++) {
+		list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
+			BUG_ON(devmap->device != NULL);
+			list_del(&devmap->list);
+			kfree(devmap);
+		}
+	}
+	spin_unlock(&dasd_devmap_lock);
+}
+
+/*
+ * Find the device struct by its device index.
+ */
+struct dasd_device *
+dasd_device_from_devindex(int devindex)
+{
+	struct dasd_devmap *devmap, *tmp;
+	struct dasd_device *device;
+	int i;
+
+	spin_lock(&dasd_devmap_lock);
+	devmap = NULL;
+	for (i = 0; (i < 256) && !devmap; i++)
+		list_for_each_entry(tmp, &dasd_hashlists[i], list)
+			if (tmp->devindex == devindex) {
+				/* Found the devmap for the device. */
+				devmap = tmp;
+				break;
+			}
+	if (devmap && devmap->device) {
+		device = devmap->device;
+		dasd_get_device(device);
+	} else
+		device = ERR_PTR(-ENODEV);
+	spin_unlock(&dasd_devmap_lock);
+	return device;
+}
+
+/*
+ * Return devmap for cdev. If no devmap exists yet, create one and
+ * connect it to the cdev.
+ */
+static struct dasd_devmap *
+dasd_devmap_from_cdev(struct ccw_device *cdev)
+{
+	struct dasd_devmap *devmap;
+
+	devmap = dasd_find_busid(dev_name(&cdev->dev));
+	if (IS_ERR(devmap))
+		devmap = dasd_add_busid(dev_name(&cdev->dev),
+					DASD_FEATURE_DEFAULT);
+	return devmap;
+}
+
+/*
+ * Create a dasd device structure for cdev.
+ */
+struct dasd_device *
+dasd_create_device(struct ccw_device *cdev)
+{
+	struct dasd_devmap *devmap;
+	struct dasd_device *device;
+	unsigned long flags;
+	int rc;
+
+	devmap = dasd_devmap_from_cdev(cdev);
+	if (IS_ERR(devmap))
+		return (void *) devmap;
+
+	device = dasd_alloc_device();
+	if (IS_ERR(device))
+		return device;
+	atomic_set(&device->ref_count, 3);
+
+	spin_lock(&dasd_devmap_lock);
+	if (!devmap->device) {
+		devmap->device = device;
+		device->devindex = devmap->devindex;
+		device->features = devmap->features;
+		get_device(&cdev->dev);
+		device->cdev = cdev;
+		rc = 0;
+	} else
+		/* Someone else was faster. */
+		rc = -EBUSY;
+	spin_unlock(&dasd_devmap_lock);
+
+	if (rc) {
+		dasd_free_device(device);
+		return ERR_PTR(rc);
+	}
+
+	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+	dev_set_drvdata(&cdev->dev, device);
+	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+
+	device->paths_info = kset_create_and_add("paths_info", NULL,
+						 &device->cdev->dev.kobj);
+	if (!device->paths_info)
+		dev_warn(&cdev->dev, "Could not create paths_info kset\n");
+
+	return device;
+}
+
+/*
+ * allocate a PPRC data structure and call the discipline function to fill
+ */
+static int dasd_devmap_get_pprc_status(struct dasd_device *device,
+				       struct dasd_pprc_data_sc4 **data)
+{
+	struct dasd_pprc_data_sc4 *temp;
+
+	if (!device->discipline || !device->discipline->pprc_status) {
+		dev_warn(&device->cdev->dev, "Unable to query copy relation status\n");
+		return -EOPNOTSUPP;
+	}
+	temp = kzalloc(sizeof(*temp), GFP_KERNEL);
+	if (!temp)
+		return -ENOMEM;
+
+	/* get PPRC information from storage */
+	if (device->discipline->pprc_status(device, temp)) {
+		dev_warn(&device->cdev->dev, "Error during copy relation status query\n");
+		kfree(temp);
+		return -EINVAL;
+	}
+	*data = temp;
+
+	return 0;
+}
+
+/*
+ * find an entry in a PPRC device_info array by a given UID
+ * depending on the primary/secondary state of the device it has to be
+ * matched with the respective fields
+ */
+static int dasd_devmap_entry_from_pprc_data(struct dasd_pprc_data_sc4 *data,
+					    struct dasd_uid uid,
+					    bool primary)
+{
+	int i;
+
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (primary) {
+			if (data->dev_info[i].prim_cu_ssid == uid.ssid &&
+			    data->dev_info[i].primary == uid.real_unit_addr)
+				return i;
+		} else {
+			if (data->dev_info[i].sec_cu_ssid == uid.ssid &&
+			    data->dev_info[i].secondary == uid.real_unit_addr)
+				return i;
+		}
+	}
+	return -1;
+}
+
+/*
+ * check the consistency of a specified copy relation by checking
+ * the following things:
+ *
+ *   - is the given device part of a copy pair setup
+ *   - does the state of the device match the state in the PPRC status data
+ *   - does the device UID match with the UID in the PPRC status data
+ *   - to prevent misrouted IO check if the given device is present in all
+ *     related PPRC status data
+ */
+static int dasd_devmap_check_copy_relation(struct dasd_device *device,
+					   struct dasd_copy_entry *entry,
+					   struct dasd_pprc_data_sc4 *data,
+					   struct dasd_copy_relation *copy)
+{
+	struct dasd_pprc_data_sc4 *tmp_dat;
+	struct dasd_device *tmp_dev;
+	struct dasd_uid uid;
+	int i, j;
+
+	if (!device->discipline || !device->discipline->get_uid ||
+	    device->discipline->get_uid(device, &uid))
+		return 1;
+
+	i = dasd_devmap_entry_from_pprc_data(data, uid, entry->primary);
+	if (i < 0) {
+		dev_warn(&device->cdev->dev, "Device not part of a copy relation\n");
+		return 1;
+	}
+
+	/* double check which role the current device has */
+	if (entry->primary) {
+		if (data->dev_info[i].flags & 0x80) {
+			dev_warn(&device->cdev->dev, "Copy pair secondary is setup as primary\n");
+			return 1;
+		}
+		if (data->dev_info[i].prim_cu_ssid != uid.ssid ||
+		    data->dev_info[i].primary != uid.real_unit_addr) {
+			dev_warn(&device->cdev->dev,
+				 "Primary device %s does not match copy pair status primary device %04x\n",
+				 dev_name(&device->cdev->dev),
+				 data->dev_info[i].prim_cu_ssid |
+				 data->dev_info[i].primary);
+			return 1;
+		}
+	} else {
+		if (!(data->dev_info[i].flags & 0x80)) {
+			dev_warn(&device->cdev->dev, "Copy pair primary is setup as secondary\n");
+			return 1;
+		}
+		if (data->dev_info[i].sec_cu_ssid != uid.ssid ||
+		    data->dev_info[i].secondary != uid.real_unit_addr) {
+			dev_warn(&device->cdev->dev,
+				 "Secondary device %s does not match copy pair status secondary device %04x\n",
+				 dev_name(&device->cdev->dev),
+				 data->dev_info[i].sec_cu_ssid |
+				 data->dev_info[i].secondary);
+			return 1;
+		}
+	}
+
+	/*
+	 * the current device has to be part of the copy relation of all
+	 * entries to prevent misrouted IO to another copy pair
+	 */
+	for (j = 0; j < DASD_CP_ENTRIES; j++) {
+		if (entry == &copy->entry[j])
+			tmp_dev = device;
+		else
+			tmp_dev = copy->entry[j].device;
+
+		if (!tmp_dev)
+			continue;
+
+		if (dasd_devmap_get_pprc_status(tmp_dev, &tmp_dat))
+			return 1;
+
+		if (dasd_devmap_entry_from_pprc_data(tmp_dat, uid, entry->primary) < 0) {
+			dev_warn(&tmp_dev->cdev->dev,
+				 "Copy pair relation does not contain device: %s\n",
+				 dev_name(&device->cdev->dev));
+			kfree(tmp_dat);
+			return 1;
+		}
+		kfree(tmp_dat);
+	}
+	return 0;
+}
+
+/* delete device from copy relation entry */
+static void dasd_devmap_delete_copy_relation_device(struct dasd_device *device)
+{
+	struct dasd_copy_relation *copy;
+	int i;
+
+	if (!device->copy)
+		return;
+
+	copy = device->copy;
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].device == device)
+			copy->entry[i].device = NULL;
+	}
+	dasd_put_device(device);
+	device->copy = NULL;
+}
+
+/*
+ * read all required information for a copy relation setup and setup the device
+ * accordingly
+ */
+int dasd_devmap_set_device_copy_relation(struct ccw_device *cdev,
+					 bool pprc_enabled)
+{
+	struct dasd_pprc_data_sc4 *data = NULL;
+	struct dasd_copy_entry *entry = NULL;
+	struct dasd_copy_relation *copy;
+	struct dasd_devmap *devmap;
+	struct dasd_device *device;
+	int i, rc = 0;
+
+	devmap = dasd_devmap_from_cdev(cdev);
+	if (IS_ERR(devmap))
+		return PTR_ERR(devmap);
+
+	device = devmap->device;
+	if (!device)
+		return -ENODEV;
+
+	copy = devmap->copy;
+	/* no copy pair setup for this device */
+	if (!copy)
+		goto out;
+
+	rc = dasd_devmap_get_pprc_status(device, &data);
+	if (rc)
+		return rc;
+
+	/* print error if PPRC is requested but not enabled on storage server */
+	if (!pprc_enabled) {
+		dev_err(&cdev->dev, "Copy relation not enabled on storage server\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (!data->dev_info[0].state) {
+		dev_warn(&device->cdev->dev, "Copy pair setup requested for device not in copy relation\n");
+		rc = -EINVAL;
+		goto out;
+	}
+	/* find entry */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].configured &&
+		    strncmp(dev_name(&cdev->dev),
+			    copy->entry[i].busid, DASD_BUS_ID_SIZE) == 0) {
+			entry = &copy->entry[i];
+			break;
+		}
+	}
+	if (!entry) {
+		dev_warn(&device->cdev->dev, "Copy relation entry not found\n");
+		rc = -EINVAL;
+		goto out;
+	}
+	/* check if the copy relation is valid */
+	if (dasd_devmap_check_copy_relation(device, entry, data, copy)) {
+		dev_warn(&device->cdev->dev, "Copy relation faulty\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	dasd_get_device(device);
+	copy->entry[i].device = device;
+	device->copy = copy;
+out:
+	kfree(data);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(dasd_devmap_set_device_copy_relation);
+
+/*
+ * Wait queue for dasd_delete_device waits.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
+
+/*
+ * Remove a dasd device structure. The passed referenced
+ * is destroyed.
+ */
+void
+dasd_delete_device(struct dasd_device *device)
+{
+	struct ccw_device *cdev;
+	struct dasd_devmap *devmap;
+	unsigned long flags;
+
+	/* First remove device pointer from devmap. */
+	devmap = dasd_find_busid(dev_name(&device->cdev->dev));
+	BUG_ON(IS_ERR(devmap));
+	spin_lock(&dasd_devmap_lock);
+	if (devmap->device != device) {
+		spin_unlock(&dasd_devmap_lock);
+		dasd_put_device(device);
+		return;
+	}
+	devmap->device = NULL;
+	spin_unlock(&dasd_devmap_lock);
+
+	/* Disconnect dasd_device structure from ccw_device structure. */
+	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
+	dev_set_drvdata(&device->cdev->dev, NULL);
+	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+
+	/* Removve copy relation */
+	dasd_devmap_delete_copy_relation_device(device);
+	/*
+	 * Drop ref_count by 3, one for the devmap reference, one for
+	 * the cdev reference and one for the passed reference.
+	 */
+	atomic_sub(3, &device->ref_count);
+
+	/* Wait for reference counter to drop to zero. */
+	wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
+
+	dasd_generic_free_discipline(device);
+
+	kset_unregister(device->paths_info);
+
+	/* Disconnect dasd_device structure from ccw_device structure. */
+	cdev = device->cdev;
+	device->cdev = NULL;
+
+	/* Put ccw_device structure. */
+	put_device(&cdev->dev);
+
+	/* Now the device structure can be freed. */
+	dasd_free_device(device);
+}
+
+/*
+ * Reference counter dropped to zero. Wake up waiter
+ * in dasd_delete_device.
+ */
+void
+dasd_put_device_wake(struct dasd_device *device)
+{
+	wake_up(&dasd_delete_wq);
+}
+EXPORT_SYMBOL_GPL(dasd_put_device_wake);
+
+/*
+ * Return dasd_device structure associated with cdev.
+ * This function needs to be called with the ccw device
+ * lock held. It can be used from interrupt context.
+ */
+struct dasd_device *
+dasd_device_from_cdev_locked(struct ccw_device *cdev)
+{
+	struct dasd_device *device = dev_get_drvdata(&cdev->dev);
+
+	if (!device)
+		return ERR_PTR(-ENODEV);
+	dasd_get_device(device);
+	return device;
+}
+
+/*
+ * Return dasd_device structure associated with cdev.
+ */
+struct dasd_device *
+dasd_device_from_cdev(struct ccw_device *cdev)
+{
+	struct dasd_device *device;
+	unsigned long flags;
+
+	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+	device = dasd_device_from_cdev_locked(cdev);
+	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+	return device;
+}
+
+void dasd_add_link_to_gendisk(struct gendisk *gdp, struct dasd_device *device)
+{
+	struct dasd_devmap *devmap;
+
+	devmap = dasd_find_busid(dev_name(&device->cdev->dev));
+	if (IS_ERR(devmap))
+		return;
+	spin_lock(&dasd_devmap_lock);
+	gdp->private_data = devmap;
+	spin_unlock(&dasd_devmap_lock);
+}
+EXPORT_SYMBOL(dasd_add_link_to_gendisk);
+
+struct dasd_device *dasd_device_from_gendisk(struct gendisk *gdp)
+{
+	struct dasd_device *device;
+	struct dasd_devmap *devmap;
+
+	if (!gdp->private_data)
+		return NULL;
+	device = NULL;
+	spin_lock(&dasd_devmap_lock);
+	devmap = gdp->private_data;
+	if (devmap && devmap->device) {
+		device = devmap->device;
+		dasd_get_device(device);
+	}
+	spin_unlock(&dasd_devmap_lock);
+	return device;
+}
+
+/*
+ * SECTION: files in sysfs
+ */
+
+/*
+ * failfast controls the behaviour, if no path is available
+ */
+static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	struct dasd_devmap *devmap;
+	int ff_flag;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
+	else
+		ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
+	return sysfs_emit(buf, ff_flag ? "1\n" : "0\n");
+}
+
+static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	unsigned int val;
+	int rc;
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	rc = dasd_set_feature(to_ccwdev(dev), DASD_FEATURE_FAILFAST, val);
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
+
+/*
+ * readonly controls the readonly status of a dasd
+ */
+static ssize_t
+dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	struct dasd_device *device;
+	int ro_flag = 0;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (IS_ERR(devmap))
+		goto out;
+
+	ro_flag = !!(devmap->features & DASD_FEATURE_READONLY);
+
+	spin_lock(&dasd_devmap_lock);
+	device = devmap->device;
+	if (device)
+		ro_flag |= test_bit(DASD_FLAG_DEVICE_RO, &device->flags);
+	spin_unlock(&dasd_devmap_lock);
+
+out:
+	return sysfs_emit(buf, ro_flag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_ro_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct ccw_device *cdev = to_ccwdev(dev);
+	struct dasd_device *device;
+	unsigned long flags;
+	unsigned int val;
+	int rc;
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	rc = dasd_set_feature(cdev, DASD_FEATURE_READONLY, val);
+	if (rc)
+		return rc;
+
+	device = dasd_device_from_cdev(cdev);
+	if (IS_ERR(device))
+		return count;
+
+	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+	val = val || test_bit(DASD_FLAG_DEVICE_RO, &device->flags);
+
+	if (!device->block || !device->block->gdp ||
+	    test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+		goto out;
+	}
+	/* Increase open_count to avoid losing the block device */
+	atomic_inc(&device->block->open_count);
+	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+
+	set_disk_ro(device->block->gdp, val);
+	atomic_dec(&device->block->open_count);
+
+out:
+	dasd_put_device(device);
+
+	return count;
+}
+
+static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
+/*
+ * erplog controls the logging of ERP related data
+ * (e.g. failing channel programs).
+ */
+static ssize_t
+dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int erplog;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
+	else
+		erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
+	return sysfs_emit(buf, erplog ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_erplog_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	unsigned int val;
+	int rc;
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	rc = dasd_set_feature(to_ccwdev(dev), DASD_FEATURE_ERPLOG, val);
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
+
+/*
+ * use_diag controls whether the driver should use diag rather than ssch
+ * to talk to the device
+ */
+static ssize_t
+dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int use_diag;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
+	else
+		use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
+	return sprintf(buf, use_diag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
+		    const char *buf, size_t count)
+{
+	struct dasd_devmap *devmap;
+	unsigned int val;
+	ssize_t rc;
+
+	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(devmap))
+		return PTR_ERR(devmap);
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	spin_lock(&dasd_devmap_lock);
+	/* Changing diag discipline flag is only allowed in offline state. */
+	rc = count;
+	if (!devmap->device && !(devmap->features & DASD_FEATURE_USERAW)) {
+		if (val)
+			devmap->features |= DASD_FEATURE_USEDIAG;
+		else
+			devmap->features &= ~DASD_FEATURE_USEDIAG;
+	} else
+		rc = -EPERM;
+	spin_unlock(&dasd_devmap_lock);
+	return rc;
+}
+
+static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
+
+/*
+ * use_raw controls whether the driver should give access to raw eckd data or
+ * operate in standard mode
+ */
+static ssize_t
+dasd_use_raw_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int use_raw;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		use_raw = (devmap->features & DASD_FEATURE_USERAW) != 0;
+	else
+		use_raw = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USERAW) != 0;
+	return sprintf(buf, use_raw ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_use_raw_store(struct device *dev, struct device_attribute *attr,
+		    const char *buf, size_t count)
+{
+	struct dasd_devmap *devmap;
+	ssize_t rc;
+	unsigned long val;
+
+	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(devmap))
+		return PTR_ERR(devmap);
+
+	if ((kstrtoul(buf, 10, &val) != 0) || val > 1)
+		return -EINVAL;
+
+	spin_lock(&dasd_devmap_lock);
+	/* Changing diag discipline flag is only allowed in offline state. */
+	rc = count;
+	if (!devmap->device && !(devmap->features & DASD_FEATURE_USEDIAG)) {
+		if (val)
+			devmap->features |= DASD_FEATURE_USERAW;
+		else
+			devmap->features &= ~DASD_FEATURE_USERAW;
+	} else
+		rc = -EPERM;
+	spin_unlock(&dasd_devmap_lock);
+	return rc;
+}
+
+static DEVICE_ATTR(raw_track_access, 0644, dasd_use_raw_show,
+		   dasd_use_raw_store);
+
+static ssize_t
+dasd_safe_offline_store(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct ccw_device *cdev = to_ccwdev(dev);
+	struct dasd_device *device;
+	unsigned long flags;
+	int rc;
+
+	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+	device = dasd_device_from_cdev_locked(cdev);
+	if (IS_ERR(device)) {
+		rc = PTR_ERR(device);
+		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+		goto out;
+	}
+
+	if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
+	    test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
+		/* Already doing offline processing */
+		dasd_put_device(device);
+		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+		rc = -EBUSY;
+		goto out;
+	}
+
+	set_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags);
+	dasd_put_device(device);
+	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+
+	rc = ccw_device_set_offline(cdev);
+
+out:
+	return rc ? rc : count;
+}
+
+static DEVICE_ATTR(safe_offline, 0200, NULL, dasd_safe_offline_store);
+
+static ssize_t
+dasd_access_show(struct device *dev, struct device_attribute *attr,
+		 char *buf)
+{
+	struct ccw_device *cdev = to_ccwdev(dev);
+	struct dasd_device *device;
+	int count;
+
+	device = dasd_device_from_cdev(cdev);
+	if (IS_ERR(device))
+		return PTR_ERR(device);
+
+	if (!device->discipline)
+		count = -ENODEV;
+	else if (!device->discipline->host_access_count)
+		count = -EOPNOTSUPP;
+	else
+		count = device->discipline->host_access_count(device);
+
+	dasd_put_device(device);
+	if (count < 0)
+		return count;
+
+	return sprintf(buf, "%d\n", count);
+}
+
+static DEVICE_ATTR(host_access_count, 0444, dasd_access_show, NULL);
+
+static ssize_t
+dasd_discipline_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct dasd_device *device;
+	ssize_t len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		goto out;
+	else if (!device->discipline) {
+		dasd_put_device(device);
+		goto out;
+	} else {
+		len = sysfs_emit(buf, "%s\n",
+				 device->discipline->name);
+		dasd_put_device(device);
+		return len;
+	}
+out:
+	len = sysfs_emit(buf, "none\n");
+	return len;
+}
+
+static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
+
+static ssize_t
+dasd_device_status_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct dasd_device *device;
+	ssize_t len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (!IS_ERR(device)) {
+		switch (device->state) {
+		case DASD_STATE_NEW:
+			len = sysfs_emit(buf, "new\n");
+			break;
+		case DASD_STATE_KNOWN:
+			len = sysfs_emit(buf, "detected\n");
+			break;
+		case DASD_STATE_BASIC:
+			len = sysfs_emit(buf, "basic\n");
+			break;
+		case DASD_STATE_UNFMT:
+			len = sysfs_emit(buf, "unformatted\n");
+			break;
+		case DASD_STATE_READY:
+			len = sysfs_emit(buf, "ready\n");
+			break;
+		case DASD_STATE_ONLINE:
+			len = sysfs_emit(buf, "online\n");
+			break;
+		default:
+			len = sysfs_emit(buf, "no stat\n");
+			break;
+		}
+		dasd_put_device(device);
+	} else
+		len = sysfs_emit(buf, "unknown\n");
+	return len;
+}
+
+static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
+
+static ssize_t dasd_alias_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	struct dasd_uid uid;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return sprintf(buf, "0\n");
+
+	if (device->discipline && device->discipline->get_uid &&
+	    !device->discipline->get_uid(device, &uid)) {
+		if (uid.type == UA_BASE_PAV_ALIAS ||
+		    uid.type == UA_HYPER_PAV_ALIAS) {
+			dasd_put_device(device);
+			return sprintf(buf, "1\n");
+		}
+	}
+	dasd_put_device(device);
+
+	return sprintf(buf, "0\n");
+}
+
+static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
+
+static ssize_t dasd_vendor_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	struct dasd_uid uid;
+	char *vendor;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	vendor = "";
+	if (IS_ERR(device))
+		return sysfs_emit(buf, "%s\n", vendor);
+
+	if (device->discipline && device->discipline->get_uid &&
+	    !device->discipline->get_uid(device, &uid))
+			vendor = uid.vendor;
+
+	dasd_put_device(device);
+
+	return sysfs_emit(buf, "%s\n", vendor);
+}
+
+static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
+
+static ssize_t
+dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	char uid_string[DASD_UID_STRLEN];
+	struct dasd_device *device;
+	struct dasd_uid uid;
+	char ua_string[3];
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	uid_string[0] = 0;
+	if (IS_ERR(device))
+		return sysfs_emit(buf, "%s\n", uid_string);
+
+	if (device->discipline && device->discipline->get_uid &&
+	    !device->discipline->get_uid(device, &uid)) {
+		switch (uid.type) {
+		case UA_BASE_DEVICE:
+			snprintf(ua_string, sizeof(ua_string), "%02x",
+				 uid.real_unit_addr);
+			break;
+		case UA_BASE_PAV_ALIAS:
+			snprintf(ua_string, sizeof(ua_string), "%02x",
+				 uid.base_unit_addr);
+			break;
+		case UA_HYPER_PAV_ALIAS:
+			snprintf(ua_string, sizeof(ua_string), "xx");
+			break;
+		default:
+			/* should not happen, treat like base device */
+			snprintf(ua_string, sizeof(ua_string), "%02x",
+				 uid.real_unit_addr);
+			break;
+		}
+
+		if (strlen(uid.vduit) > 0)
+			snprintf(uid_string, sizeof(uid_string),
+				 "%s.%s.%04x.%s.%s",
+				 uid.vendor, uid.serial, uid.ssid, ua_string,
+				 uid.vduit);
+		else
+			snprintf(uid_string, sizeof(uid_string),
+				 "%s.%s.%04x.%s",
+				 uid.vendor, uid.serial, uid.ssid, ua_string);
+	}
+	dasd_put_device(device);
+
+	return sysfs_emit(buf, "%s\n", uid_string);
+}
+static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
+
+/*
+ * extended error-reporting
+ */
+static ssize_t
+dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int eer_flag;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap) && devmap->device)
+		eer_flag = dasd_eer_enabled(devmap->device);
+	else
+		eer_flag = 0;
+	return sysfs_emit(buf, eer_flag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_eer_store(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned int val;
+	int rc = 0;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return PTR_ERR(device);
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	if (val)
+		rc = dasd_eer_enable(device);
+	else
+		dasd_eer_disable(device);
+
+	dasd_put_device(device);
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
+
+/*
+ * expiration time for default requests
+ */
+static ssize_t
+dasd_expires_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	int len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	len = sysfs_emit(buf, "%lu\n", device->default_expires);
+	dasd_put_device(device);
+	return len;
+}
+
+static ssize_t
+dasd_expires_store(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned long val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if ((kstrtoul(buf, 10, &val) != 0) ||
+	    (val > DASD_EXPIRES_MAX) || val == 0) {
+		dasd_put_device(device);
+		return -EINVAL;
+	}
+
+	if (val)
+		device->default_expires = val;
+
+	dasd_put_device(device);
+	return count;
+}
+
+static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store);
+
+static ssize_t
+dasd_retries_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	int len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	len = sysfs_emit(buf, "%lu\n", device->default_retries);
+	dasd_put_device(device);
+	return len;
+}
+
+static ssize_t
+dasd_retries_store(struct device *dev, struct device_attribute *attr,
+		   const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned long val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if ((kstrtoul(buf, 10, &val) != 0) ||
+	    (val > DASD_RETRIES_MAX)) {
+		dasd_put_device(device);
+		return -EINVAL;
+	}
+
+	if (val)
+		device->default_retries = val;
+
+	dasd_put_device(device);
+	return count;
+}
+
+static DEVICE_ATTR(retries, 0644, dasd_retries_show, dasd_retries_store);
+
+static ssize_t
+dasd_timeout_show(struct device *dev, struct device_attribute *attr,
+		  char *buf)
+{
+	struct dasd_device *device;
+	int len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	len = sysfs_emit(buf, "%lu\n", device->blk_timeout);
+	dasd_put_device(device);
+	return len;
+}
+
+static ssize_t
+dasd_timeout_store(struct device *dev, struct device_attribute *attr,
+		   const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned long val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device) || !device->block)
+		return -ENODEV;
+
+	if ((kstrtoul(buf, 10, &val) != 0) ||
+	    val > UINT_MAX / HZ) {
+		dasd_put_device(device);
+		return -EINVAL;
+	}
+	if (!device->block->gdp) {
+		dasd_put_device(device);
+		return -ENODEV;
+	}
+
+	device->blk_timeout = val;
+	blk_queue_rq_timeout(device->block->gdp->queue, val * HZ);
+
+	dasd_put_device(device);
+	return count;
+}
+
+static DEVICE_ATTR(timeout, 0644,
+		   dasd_timeout_show, dasd_timeout_store);
+
+
+static ssize_t
+dasd_path_reset_store(struct device *dev, struct device_attribute *attr,
+		      const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned int val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if ((kstrtouint(buf, 16, &val) != 0) || val > 0xff)
+		val = 0;
+
+	if (device->discipline && device->discipline->reset_path)
+		device->discipline->reset_path(device, (__u8) val);
+
+	dasd_put_device(device);
+	return count;
+}
+
+static DEVICE_ATTR(path_reset, 0200, NULL, dasd_path_reset_store);
+
+static ssize_t dasd_hpf_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct dasd_device *device;
+	int hpf;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	if (!device->discipline || !device->discipline->hpf_enabled) {
+		dasd_put_device(device);
+		return sysfs_emit(buf, "%d\n", dasd_nofcx);
+	}
+	hpf = device->discipline->hpf_enabled(device);
+	dasd_put_device(device);
+	return sysfs_emit(buf, "%d\n", hpf);
+}
+
+static DEVICE_ATTR(hpf, 0444, dasd_hpf_show, NULL);
+
+static ssize_t dasd_reservation_policy_show(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	struct dasd_devmap *devmap;
+	int rc = 0;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (IS_ERR(devmap)) {
+		rc = sysfs_emit(buf, "ignore\n");
+	} else {
+		spin_lock(&dasd_devmap_lock);
+		if (devmap->features & DASD_FEATURE_FAILONSLCK)
+			rc = sysfs_emit(buf, "fail\n");
+		else
+			rc = sysfs_emit(buf, "ignore\n");
+		spin_unlock(&dasd_devmap_lock);
+	}
+	return rc;
+}
+
+static ssize_t dasd_reservation_policy_store(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count)
+{
+	struct ccw_device *cdev = to_ccwdev(dev);
+	int rc;
+
+	if (sysfs_streq("ignore", buf))
+		rc = dasd_set_feature(cdev, DASD_FEATURE_FAILONSLCK, 0);
+	else if (sysfs_streq("fail", buf))
+		rc = dasd_set_feature(cdev, DASD_FEATURE_FAILONSLCK, 1);
+	else
+		rc = -EINVAL;
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(reservation_policy, 0644,
+		   dasd_reservation_policy_show, dasd_reservation_policy_store);
+
+static ssize_t dasd_reservation_state_show(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct dasd_device *device;
+	int rc = 0;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return sysfs_emit(buf, "none\n");
+
+	if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags))
+		rc = sysfs_emit(buf, "reserved\n");
+	else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags))
+		rc = sysfs_emit(buf, "lost\n");
+	else
+		rc = sysfs_emit(buf, "none\n");
+	dasd_put_device(device);
+	return rc;
+}
+
+static ssize_t dasd_reservation_state_store(struct device *dev,
+					    struct device_attribute *attr,
+					    const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	int rc = 0;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	if (sysfs_streq("reset", buf))
+		clear_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
+	else
+		rc = -EINVAL;
+	dasd_put_device(device);
+
+	if (rc)
+		return rc;
+	else
+		return count;
+}
+
+static DEVICE_ATTR(last_known_reservation_state, 0644,
+		   dasd_reservation_state_show, dasd_reservation_state_store);
+
+static ssize_t dasd_pm_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	u8 opm, nppm, cablepm, cuirpm, hpfpm, ifccpm;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return sprintf(buf, "0\n");
+
+	opm = dasd_path_get_opm(device);
+	nppm = dasd_path_get_nppm(device);
+	cablepm = dasd_path_get_cablepm(device);
+	cuirpm = dasd_path_get_cuirpm(device);
+	hpfpm = dasd_path_get_hpfpm(device);
+	ifccpm = dasd_path_get_ifccpm(device);
+	dasd_put_device(device);
+
+	return sprintf(buf, "%02x %02x %02x %02x %02x %02x\n", opm, nppm,
+		       cablepm, cuirpm, hpfpm, ifccpm);
+}
+
+static DEVICE_ATTR(path_masks, 0444, dasd_pm_show, NULL);
+
+/*
+ * threshold value for IFCC/CCC errors
+ */
+static ssize_t
+dasd_path_threshold_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	int len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	len = sysfs_emit(buf, "%lu\n", device->path_thrhld);
+	dasd_put_device(device);
+	return len;
+}
+
+static ssize_t
+dasd_path_threshold_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned long flags;
+	unsigned long val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if (kstrtoul(buf, 10, &val) != 0 || val > DASD_THRHLD_MAX) {
+		dasd_put_device(device);
+		return -EINVAL;
+	}
+	spin_lock_irqsave(get_ccwdev_lock(to_ccwdev(dev)), flags);
+	device->path_thrhld = val;
+	spin_unlock_irqrestore(get_ccwdev_lock(to_ccwdev(dev)), flags);
+	dasd_put_device(device);
+	return count;
+}
+static DEVICE_ATTR(path_threshold, 0644, dasd_path_threshold_show,
+		   dasd_path_threshold_store);
+
+/*
+ * configure if path is disabled after IFCC/CCC error threshold is
+ * exceeded
+ */
+static ssize_t
+dasd_path_autodisable_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int flag;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		flag = (devmap->features & DASD_FEATURE_PATH_AUTODISABLE) != 0;
+	else
+		flag = (DASD_FEATURE_DEFAULT &
+			DASD_FEATURE_PATH_AUTODISABLE) != 0;
+	return sysfs_emit(buf, flag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_path_autodisable_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	unsigned int val;
+	int rc;
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	rc = dasd_set_feature(to_ccwdev(dev),
+			      DASD_FEATURE_PATH_AUTODISABLE, val);
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(path_autodisable, 0644,
+		   dasd_path_autodisable_show,
+		   dasd_path_autodisable_store);
+/*
+ * interval for IFCC/CCC checks
+ * meaning time with no IFCC/CCC error before the error counter
+ * gets reset
+ */
+static ssize_t
+dasd_path_interval_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct dasd_device *device;
+	int len;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	len = sysfs_emit(buf, "%lu\n", device->path_interval);
+	dasd_put_device(device);
+	return len;
+}
+
+static ssize_t
+dasd_path_interval_store(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	unsigned long flags;
+	unsigned long val;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if ((kstrtoul(buf, 10, &val) != 0) ||
+	    (val > DASD_INTERVAL_MAX) || val == 0) {
+		dasd_put_device(device);
+		return -EINVAL;
+	}
+	spin_lock_irqsave(get_ccwdev_lock(to_ccwdev(dev)), flags);
+	if (val)
+		device->path_interval = val;
+	spin_unlock_irqrestore(get_ccwdev_lock(to_ccwdev(dev)), flags);
+	dasd_put_device(device);
+	return count;
+}
+
+static DEVICE_ATTR(path_interval, 0644, dasd_path_interval_show,
+		   dasd_path_interval_store);
+
+static ssize_t
+dasd_device_fcs_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct dasd_device *device;
+	int fc_sec;
+	int rc;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+	fc_sec = dasd_path_get_fcs_device(device);
+	if (fc_sec == -EINVAL)
+		rc = sysfs_emit(buf, "Inconsistent\n");
+	else
+		rc = sysfs_emit(buf, "%s\n", dasd_path_get_fcs_str(fc_sec));
+	dasd_put_device(device);
+
+	return rc;
+}
+static DEVICE_ATTR(fc_security, 0444, dasd_device_fcs_show, NULL);
+
+static ssize_t
+dasd_path_fcs_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	struct dasd_path *path = to_dasd_path(kobj);
+	unsigned int fc_sec = path->fc_security;
+
+	return sysfs_emit(buf, "%s\n", dasd_path_get_fcs_str(fc_sec));
+}
+
+static struct kobj_attribute path_fcs_attribute =
+	__ATTR(fc_security, 0444, dasd_path_fcs_show, NULL);
+
+/*
+ * print copy relation in the form
+ * primary,secondary[1] primary,secondary[2], ...
+ */
+static ssize_t
+dasd_copy_pair_show(struct device *dev,
+		    struct device_attribute *attr, char *buf)
+{
+	char prim_busid[DASD_BUS_ID_SIZE];
+	struct dasd_copy_relation *copy;
+	struct dasd_devmap *devmap;
+	int len = 0;
+	int i;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (IS_ERR(devmap))
+		return -ENODEV;
+
+	if (!devmap->copy)
+		return -ENODEV;
+
+	copy = devmap->copy;
+	/* find primary */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].configured && copy->entry[i].primary) {
+			strscpy(prim_busid, copy->entry[i].busid,
+				DASD_BUS_ID_SIZE);
+			break;
+		}
+	}
+	if (i == DASD_CP_ENTRIES)
+		goto out;
+
+	/* print all secondary */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].configured && !copy->entry[i].primary)
+			len += sysfs_emit_at(buf, len, "%s,%s ", prim_busid,
+					     copy->entry[i].busid);
+	}
+
+	len += sysfs_emit_at(buf, len, "\n");
+out:
+	return len;
+}
+
+static int dasd_devmap_set_copy_relation(struct dasd_devmap *devmap,
+					 struct dasd_copy_relation *copy,
+					 char *busid, bool primary)
+{
+	int i;
+
+	/* find free entry */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		/* current bus_id already included, nothing to do */
+		if (copy->entry[i].configured &&
+		    strncmp(copy->entry[i].busid, busid, DASD_BUS_ID_SIZE) == 0)
+			return 0;
+
+		if (!copy->entry[i].configured)
+			break;
+	}
+	if (i == DASD_CP_ENTRIES)
+		return -EINVAL;
+
+	copy->entry[i].configured = true;
+	strscpy(copy->entry[i].busid, busid, DASD_BUS_ID_SIZE);
+	if (primary) {
+		copy->active = &copy->entry[i];
+		copy->entry[i].primary = true;
+	}
+	if (!devmap->copy)
+		devmap->copy = copy;
+
+	return 0;
+}
+
+static void dasd_devmap_del_copy_relation(struct dasd_copy_relation *copy,
+					  char *busid)
+{
+	int i;
+
+	spin_lock(&dasd_devmap_lock);
+	/* find entry */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].configured &&
+		    strncmp(copy->entry[i].busid, busid, DASD_BUS_ID_SIZE) == 0)
+			break;
+	}
+	if (i == DASD_CP_ENTRIES || !copy->entry[i].configured) {
+		spin_unlock(&dasd_devmap_lock);
+		return;
+	}
+
+	copy->entry[i].configured = false;
+	memset(copy->entry[i].busid, 0, DASD_BUS_ID_SIZE);
+	if (copy->active == &copy->entry[i]) {
+		copy->active = NULL;
+		copy->entry[i].primary = false;
+	}
+	spin_unlock(&dasd_devmap_lock);
+}
+
+static int dasd_devmap_clear_copy_relation(struct device *dev)
+{
+	struct dasd_copy_relation *copy;
+	struct dasd_devmap *devmap;
+	int i, rc = 1;
+
+	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(devmap))
+		return 1;
+
+	spin_lock(&dasd_devmap_lock);
+	if (!devmap->copy)
+		goto out;
+
+	copy = devmap->copy;
+	/* first check if all secondary devices are offline*/
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (!copy->entry[i].configured)
+			continue;
+
+		if (copy->entry[i].device == copy->active->device)
+			continue;
+
+		if (copy->entry[i].device)
+			goto out;
+	}
+	/* clear all devmap entries */
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (strlen(copy->entry[i].busid) == 0)
+			continue;
+		if (copy->entry[i].device) {
+			dasd_put_device(copy->entry[i].device);
+			copy->entry[i].device->copy = NULL;
+			copy->entry[i].device = NULL;
+		}
+		devmap = dasd_find_busid_locked(copy->entry[i].busid);
+		devmap->copy = NULL;
+		memset(copy->entry[i].busid, 0, DASD_BUS_ID_SIZE);
+	}
+	kfree(copy);
+	rc = 0;
+out:
+	spin_unlock(&dasd_devmap_lock);
+	return rc;
+}
+
+/*
+ * parse BUSIDs from a copy pair
+ */
+static int dasd_devmap_parse_busid(const char *buf, char *prim_busid,
+				   char *sec_busid)
+{
+	char *primary, *secondary, *tmp, *pt;
+	int id0, id1, id2;
+
+	pt =  kstrdup(buf, GFP_KERNEL);
+	tmp = pt;
+	if (!tmp)
+		return -ENOMEM;
+
+	primary = strsep(&tmp, ",");
+	if (!primary) {
+		kfree(pt);
+		return -EINVAL;
+	}
+	secondary = strsep(&tmp, ",");
+	if (!secondary) {
+		kfree(pt);
+		return -EINVAL;
+	}
+	if (dasd_busid(primary, &id0, &id1, &id2)) {
+		kfree(pt);
+		return -EINVAL;
+	}
+	sprintf(prim_busid, "%01x.%01x.%04x", id0, id1, id2);
+	if (dasd_busid(secondary, &id0, &id1, &id2)) {
+		kfree(pt);
+		return -EINVAL;
+	}
+	sprintf(sec_busid, "%01x.%01x.%04x", id0, id1, id2);
+	kfree(pt);
+
+	return 0;
+}
+
+static ssize_t dasd_copy_pair_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	struct dasd_devmap *prim_devmap, *sec_devmap;
+	char prim_busid[DASD_BUS_ID_SIZE];
+	char sec_busid[DASD_BUS_ID_SIZE];
+	struct dasd_copy_relation *copy;
+	struct dasd_device *device;
+	bool pprc_enabled;
+	int rc;
+
+	if (strncmp(buf, "clear", strlen("clear")) == 0) {
+		if (dasd_devmap_clear_copy_relation(dev))
+			return -EINVAL;
+		return count;
+	}
+
+	rc = dasd_devmap_parse_busid(buf, prim_busid, sec_busid);
+	if (rc)
+		return rc;
+
+	if (strncmp(dev_name(dev), prim_busid, DASD_BUS_ID_SIZE) != 0 &&
+	    strncmp(dev_name(dev), sec_busid, DASD_BUS_ID_SIZE) != 0)
+		return -EINVAL;
+
+	/* allocate primary devmap if needed */
+	prim_devmap = dasd_find_busid(prim_busid);
+	if (IS_ERR(prim_devmap))
+		prim_devmap = dasd_add_busid(prim_busid, DASD_FEATURE_DEFAULT);
+
+	/* allocate secondary devmap if needed */
+	sec_devmap = dasd_find_busid(sec_busid);
+	if (IS_ERR(sec_devmap))
+		sec_devmap = dasd_add_busid(sec_busid, DASD_FEATURE_DEFAULT);
+
+	/* setting copy relation is only allowed for offline secondary */
+	if (sec_devmap->device)
+		return -EINVAL;
+
+	if (prim_devmap->copy) {
+		copy = prim_devmap->copy;
+	} else if (sec_devmap->copy) {
+		copy = sec_devmap->copy;
+	} else {
+		copy = kzalloc(sizeof(*copy), GFP_KERNEL);
+		if (!copy)
+			return -ENOMEM;
+	}
+	spin_lock(&dasd_devmap_lock);
+	rc = dasd_devmap_set_copy_relation(prim_devmap, copy, prim_busid, true);
+	if (rc) {
+		spin_unlock(&dasd_devmap_lock);
+		return rc;
+	}
+	rc = dasd_devmap_set_copy_relation(sec_devmap, copy, sec_busid, false);
+	if (rc) {
+		spin_unlock(&dasd_devmap_lock);
+		return rc;
+	}
+	spin_unlock(&dasd_devmap_lock);
+
+	/* if primary device is already online call device setup directly */
+	if (prim_devmap->device && !prim_devmap->device->copy) {
+		device = prim_devmap->device;
+		if (device->discipline->pprc_enabled) {
+			pprc_enabled = device->discipline->pprc_enabled(device);
+			rc = dasd_devmap_set_device_copy_relation(device->cdev,
+								  pprc_enabled);
+		} else {
+			rc = -EOPNOTSUPP;
+		}
+	}
+	if (rc) {
+		dasd_devmap_del_copy_relation(copy, prim_busid);
+		dasd_devmap_del_copy_relation(copy, sec_busid);
+		count = rc;
+	}
+
+	return count;
+}
+static DEVICE_ATTR(copy_pair, 0644, dasd_copy_pair_show,
+		   dasd_copy_pair_store);
+
+static ssize_t
+dasd_copy_role_show(struct device *dev,
+		    struct device_attribute *attr, char *buf)
+{
+	struct dasd_copy_relation *copy;
+	struct dasd_device *device;
+	int len, i;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	if (!device->copy) {
+		len = sysfs_emit(buf, "none\n");
+		goto out;
+	}
+	copy = device->copy;
+	/* only the active device is primary */
+	if (copy->active->device == device) {
+		len = sysfs_emit(buf, "primary\n");
+		goto out;
+	}
+	for (i = 0; i < DASD_CP_ENTRIES; i++) {
+		if (copy->entry[i].device == device) {
+			len = sysfs_emit(buf, "secondary\n");
+			goto out;
+		}
+	}
+	/* not in the list, no COPY role */
+	len = sysfs_emit(buf, "none\n");
+out:
+	dasd_put_device(device);
+	return len;
+}
+static DEVICE_ATTR(copy_role, 0444, dasd_copy_role_show, NULL);
+
+static ssize_t dasd_device_ping(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct dasd_device *device;
+	size_t rc;
+
+	device = dasd_device_from_cdev(to_ccwdev(dev));
+	if (IS_ERR(device))
+		return -ENODEV;
+
+	/*
+	 * do not try during offline processing
+	 * early check only
+	 * the sleep_on function itself checks for offline
+	 * processing again
+	 */
+	if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+		rc = -EBUSY;
+		goto out;
+	}
+	if (!device->discipline || !device->discipline->device_ping) {
+		rc = -EOPNOTSUPP;
+		goto out;
+	}
+	rc = device->discipline->device_ping(device);
+	if (!rc)
+		rc = count;
+out:
+	dasd_put_device(device);
+	return rc;
+}
+static DEVICE_ATTR(ping, 0200, NULL, dasd_device_ping);
+
+#define DASD_DEFINE_ATTR(_name, _func)					\
+static ssize_t dasd_##_name##_show(struct device *dev,			\
+				   struct device_attribute *attr,	\
+				   char *buf)				\
+{									\
+	struct ccw_device *cdev = to_ccwdev(dev);			\
+	struct dasd_device *device = dasd_device_from_cdev(cdev);	\
+	int val = 0;							\
+									\
+	if (IS_ERR(device))						\
+		return -ENODEV;						\
+	if (device->discipline && _func)				\
+		val = _func(device);					\
+	dasd_put_device(device);					\
+									\
+	return sysfs_emit(buf, "%d\n", val);			\
+}									\
+static DEVICE_ATTR(_name, 0444, dasd_##_name##_show, NULL);		\
+
+DASD_DEFINE_ATTR(ese, device->discipline->is_ese);
+DASD_DEFINE_ATTR(extent_size, device->discipline->ext_size);
+DASD_DEFINE_ATTR(pool_id, device->discipline->ext_pool_id);
+DASD_DEFINE_ATTR(space_configured, device->discipline->space_configured);
+DASD_DEFINE_ATTR(space_allocated, device->discipline->space_allocated);
+DASD_DEFINE_ATTR(logical_capacity, device->discipline->logical_capacity);
+DASD_DEFINE_ATTR(warn_threshold, device->discipline->ext_pool_warn_thrshld);
+DASD_DEFINE_ATTR(cap_at_warnlevel, device->discipline->ext_pool_cap_at_warnlevel);
+DASD_DEFINE_ATTR(pool_oos, device->discipline->ext_pool_oos);
+
+static struct attribute * dasd_attrs[] = {
+	&dev_attr_readonly.attr,
+	&dev_attr_discipline.attr,
+	&dev_attr_status.attr,
+	&dev_attr_alias.attr,
+	&dev_attr_vendor.attr,
+	&dev_attr_uid.attr,
+	&dev_attr_use_diag.attr,
+	&dev_attr_raw_track_access.attr,
+	&dev_attr_eer_enabled.attr,
+	&dev_attr_erplog.attr,
+	&dev_attr_failfast.attr,
+	&dev_attr_expires.attr,
+	&dev_attr_retries.attr,
+	&dev_attr_timeout.attr,
+	&dev_attr_reservation_policy.attr,
+	&dev_attr_last_known_reservation_state.attr,
+	&dev_attr_safe_offline.attr,
+	&dev_attr_host_access_count.attr,
+	&dev_attr_path_masks.attr,
+	&dev_attr_path_threshold.attr,
+	&dev_attr_path_autodisable.attr,
+	&dev_attr_path_interval.attr,
+	&dev_attr_path_reset.attr,
+	&dev_attr_hpf.attr,
+	&dev_attr_ese.attr,
+	&dev_attr_fc_security.attr,
+	&dev_attr_copy_pair.attr,
+	&dev_attr_copy_role.attr,
+	&dev_attr_ping.attr,
+	NULL,
+};
+
+static const struct attribute_group dasd_attr_group = {
+	.attrs = dasd_attrs,
+};
+
+static struct attribute *capacity_attrs[] = {
+	&dev_attr_space_configured.attr,
+	&dev_attr_space_allocated.attr,
+	&dev_attr_logical_capacity.attr,
+	NULL,
+};
+
+static const struct attribute_group capacity_attr_group = {
+	.name = "capacity",
+	.attrs = capacity_attrs,
+};
+
+static struct attribute *ext_pool_attrs[] = {
+	&dev_attr_pool_id.attr,
+	&dev_attr_extent_size.attr,
+	&dev_attr_warn_threshold.attr,
+	&dev_attr_cap_at_warnlevel.attr,
+	&dev_attr_pool_oos.attr,
+	NULL,
+};
+
+static const struct attribute_group ext_pool_attr_group = {
+	.name = "extent_pool",
+	.attrs = ext_pool_attrs,
+};
+
+const struct attribute_group *dasd_dev_groups[] = {
+	&dasd_attr_group,
+	&capacity_attr_group,
+	&ext_pool_attr_group,
+	NULL,
+};
+EXPORT_SYMBOL_GPL(dasd_dev_groups);
+
+/*
+ * Return value of the specified feature.
+ */
+int
+dasd_get_feature(struct ccw_device *cdev, int feature)
+{
+	struct dasd_devmap *devmap;
+
+	devmap = dasd_find_busid(dev_name(&cdev->dev));
+	if (IS_ERR(devmap))
+		return PTR_ERR(devmap);
+
+	return ((devmap->features & feature) != 0);
+}
+
+/*
+ * Set / reset given feature.
+ * Flag indicates whether to set (!=0) or the reset (=0) the feature.
+ */
+int
+dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
+{
+	struct dasd_devmap *devmap;
+
+	devmap = dasd_devmap_from_cdev(cdev);
+	if (IS_ERR(devmap))
+		return PTR_ERR(devmap);
+
+	spin_lock(&dasd_devmap_lock);
+	if (flag)
+		devmap->features |= feature;
+	else
+		devmap->features &= ~feature;
+	if (devmap->device)
+		devmap->device->features = devmap->features;
+	spin_unlock(&dasd_devmap_lock);
+	return 0;
+}
+EXPORT_SYMBOL(dasd_set_feature);
+
+static struct attribute *paths_info_attrs[] = {
+	&path_fcs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(paths_info);
+
+static struct kobj_type path_attr_type = {
+	.release	= dasd_path_release,
+	.default_groups	= paths_info_groups,
+	.sysfs_ops	= &kobj_sysfs_ops,
+};
+
+static void dasd_path_init_kobj(struct dasd_device *device, int chp)
+{
+	device->path[chp].kobj.kset = device->paths_info;
+	kobject_init(&device->path[chp].kobj, &path_attr_type);
+}
+
+void dasd_path_create_kobj(struct dasd_device *device, int chp)
+{
+	int rc;
+
+	if (test_bit(DASD_FLAG_OFFLINE, &device->flags))
+		return;
+	if (!device->paths_info) {
+		dev_warn(&device->cdev->dev, "Unable to create paths objects\n");
+		return;
+	}
+	if (device->path[chp].in_sysfs)
+		return;
+	if (!device->path[chp].conf_data)
+		return;
+
+	dasd_path_init_kobj(device, chp);
+
+	rc = kobject_add(&device->path[chp].kobj, NULL, "%x.%02x",
+			 device->path[chp].cssid, device->path[chp].chpid);
+	if (rc)
+		kobject_put(&device->path[chp].kobj);
+	device->path[chp].in_sysfs = true;
+}
+EXPORT_SYMBOL(dasd_path_create_kobj);
+
+void dasd_path_create_kobjects(struct dasd_device *device)
+{
+	u8 lpm, opm;
+
+	opm = dasd_path_get_opm(device);
+	for (lpm = 0x80; lpm; lpm >>= 1) {
+		if (!(lpm & opm))
+			continue;
+		dasd_path_create_kobj(device, pathmask_to_pos(lpm));
+	}
+}
+EXPORT_SYMBOL(dasd_path_create_kobjects);
+
+static void dasd_path_remove_kobj(struct dasd_device *device, int chp)
+{
+	if (device->path[chp].in_sysfs) {
+		kobject_put(&device->path[chp].kobj);
+		device->path[chp].in_sysfs = false;
+	}
+}
+
+/*
+ * As we keep kobjects for the lifetime of a device, this function must not be
+ * called anywhere but in the context of offlining a device.
+ */
+void dasd_path_remove_kobjects(struct dasd_device *device)
+{
+	int i;
+
+	for (i = 0; i < 8; i++)
+		dasd_path_remove_kobj(device, i);
+}
+EXPORT_SYMBOL(dasd_path_remove_kobjects);
+
+int
+dasd_devmap_init(void)
+{
+	int i;
+
+	/* Initialize devmap structures. */
+	dasd_max_devindex = 0;
+	for (i = 0; i < 256; i++)
+		INIT_LIST_HEAD(&dasd_hashlists[i]);
+	return 0;
+}
+
+void
+dasd_devmap_exit(void)
+{
+	dasd_forget_ranges();
+}