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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/s390/block/dasd_devmap.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/s390/block/dasd_devmap.c')
-rw-r--r--drivers/s390/block/dasd_devmap.c772
1 files changed, 772 insertions, 0 deletions
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
new file mode 100644
index 00000000000..ad1841a96c8
--- /dev/null
+++ b/drivers/s390/block/dasd_devmap.c
@@ -0,0 +1,772 @@
+/*
+ * File...........: linux/drivers/s390/block/dasd_devmap.c
+ * 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>
+ * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 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.
+ *
+ * $Revision: 1.37 $
+ */
+
+#include <linux/config.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+
+#include <asm/debug.h>
+#include <asm/uaccess.h>
+
+/* This is ugly... */
+#define PRINTK_HEADER "dasd_devmap:"
+
+#include "dasd_int.h"
+
+kmem_cache_t *dasd_page_cache;
+EXPORT_SYMBOL(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[BUS_ID_SIZE];
+ unsigned int devindex;
+ unsigned short features;
+ struct dasd_device *device;
+};
+
+/*
+ * 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 */
+
+/*
+ * 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[256];
+/*
+ * Single spinlock to protect devmap 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(char *, int);
+
+static inline int
+dasd_hash_busid(char *bus_id)
+{
+ int hash, i;
+
+ hash = 0;
+ for (i = 0; (i < BUS_ID_SIZE) && *bus_id; i++, bus_id++)
+ hash += *bus_id;
+ return hash & 0xff;
+}
+
+#ifndef MODULE
+/*
+ * The parameter parsing functions for builtin-drivers are called
+ * before kmalloc works. Store the pointers to the parameters strings
+ * into dasd[] for later processing.
+ */
+static int __init
+dasd_call_setup(char *str)
+{
+ static int count = 0;
+
+ if (count < 256)
+ dasd[count++] = str;
+ return 1;
+}
+
+__setup ("dasd=", dasd_call_setup);
+#endif /* #ifndef MODULE */
+
+/*
+ * Read a device busid/devno from a string.
+ */
+static inline int
+dasd_busid(char **str, int *id0, int *id1, int *devno)
+{
+ int val, old_style;
+
+ /* check for leading '0x' */
+ old_style = 0;
+ if ((*str)[0] == '0' && (*str)[1] == 'x') {
+ *str += 2;
+ old_style = 1;
+ }
+ if (!isxdigit((*str)[0])) /* We require at least one hex digit */
+ return -EINVAL;
+ val = simple_strtoul(*str, str, 16);
+ if (old_style || (*str)[0] != '.') {
+ *id0 = *id1 = 0;
+ if (val < 0 || val > 0xffff)
+ return -EINVAL;
+ *devno = val;
+ return 0;
+ }
+ /* New style x.y.z busid */
+ if (val < 0 || val > 0xff)
+ return -EINVAL;
+ *id0 = val;
+ (*str)++;
+ if (!isxdigit((*str)[0])) /* We require at least one hex digit */
+ return -EINVAL;
+ val = simple_strtoul(*str, str, 16);
+ if (val < 0 || val > 0xff || (*str)++[0] != '.')
+ return -EINVAL;
+ *id1 = val;
+ if (!isxdigit((*str)[0])) /* We require at least one hex digit */
+ return -EINVAL;
+ val = simple_strtoul(*str, str, 16);
+ if (val < 0 || val > 0xffff)
+ return -EINVAL;
+ *devno = val;
+ return 0;
+}
+
+/*
+ * Read colon separated list of dasd features. Currently there is
+ * only one: "ro" for read-only devices. The default feature set
+ * is empty (value 0).
+ */
+static inline int
+dasd_feature_list(char *str, char **endp)
+{
+ int features, len, rc;
+
+ rc = 0;
+ if (*str != '(') {
+ *endp = str;
+ return DASD_FEATURE_DEFAULT;
+ }
+ str++;
+ features = 0;
+
+ 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 {
+ MESSAGE(KERN_WARNING,
+ "unsupported feature: %*s, "
+ "ignoring setting", len, str);
+ rc = -EINVAL;
+ }
+ str += len;
+ if (*str != ':')
+ break;
+ str++;
+ }
+ if (*str != ')') {
+ MESSAGE(KERN_WARNING, "%s",
+ "missing ')' in dasd parameter string\n");
+ rc = -EINVAL;
+ } else
+ str++;
+ *endp = str;
+ if (rc != 0)
+ return rc;
+ return 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 char *
+dasd_parse_keyword( char *parsestring ) {
+
+ char *nextcomma, *residual_str;
+ int length;
+
+ nextcomma = strchr(parsestring,',');
+ if (nextcomma) {
+ length = nextcomma - parsestring;
+ residual_str = nextcomma + 1;
+ } else {
+ length = strlen(parsestring);
+ residual_str = parsestring + length;
+ }
+ if (strncmp ("autodetect", parsestring, length) == 0) {
+ dasd_autodetect = 1;
+ MESSAGE (KERN_INFO, "%s",
+ "turning to autodetection mode");
+ return residual_str;
+ }
+ if (strncmp ("probeonly", parsestring, length) == 0) {
+ dasd_probeonly = 1;
+ MESSAGE(KERN_INFO, "%s",
+ "turning to probeonly mode");
+ return residual_str;
+ }
+ if (strncmp ("fixedbuffers", parsestring, length) == 0) {
+ if (dasd_page_cache)
+ return residual_str;
+ dasd_page_cache =
+ kmem_cache_create("dasd_page_cache", PAGE_SIZE, 0,
+ SLAB_CACHE_DMA, NULL, NULL );
+ if (!dasd_page_cache)
+ MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
+ "fixed buffer mode disabled.");
+ else
+ MESSAGE (KERN_INFO, "%s",
+ "turning on fixed buffer mode");
+ return residual_str;
+ }
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Try to interprete the first element on the comma separated parse string
+ * as a device number or a range of devices. If the interpretation is
+ * successfull, create the matching dasd_devmap entries and return a pointer
+ * to the residual string.
+ * If interpretation fails or in case of an error, return an error code.
+ */
+static char *
+dasd_parse_range( char *parsestring ) {
+
+ struct dasd_devmap *devmap;
+ int from, from_id0, from_id1;
+ int to, to_id0, to_id1;
+ int features, rc;
+ char bus_id[BUS_ID_SIZE+1], *str;
+
+ str = parsestring;
+ rc = dasd_busid(&str, &from_id0, &from_id1, &from);
+ if (rc == 0) {
+ to = from;
+ to_id0 = from_id0;
+ to_id1 = from_id1;
+ if (*str == '-') {
+ str++;
+ rc = dasd_busid(&str, &to_id0, &to_id1, &to);
+ }
+ }
+ if (rc == 0 &&
+ (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
+ rc = -EINVAL;
+ if (rc) {
+ MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
+ return ERR_PTR(rc);
+ }
+ features = dasd_feature_list(str, &str);
+ if (features < 0)
+ return ERR_PTR(-EINVAL);
+ 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))
+ return (char *)devmap;
+ }
+ if (*str == ',')
+ return str + 1;
+ if (*str == '\0')
+ return str;
+ MESSAGE(KERN_WARNING,
+ "junk at end of dasd parameter string: %s\n", str);
+ return ERR_PTR(-EINVAL);
+}
+
+static inline char *
+dasd_parse_next_element( char *parsestring ) {
+ char * residual_str;
+ residual_str = dasd_parse_keyword(parsestring);
+ if (!IS_ERR(residual_str))
+ return residual_str;
+ residual_str = dasd_parse_range(parsestring);
+ return residual_str;
+}
+
+/*
+ * Parse parameters stored in dasd[]
+ * The 'dasd=...' parameter allows to specify a comma separated list of
+ * keywords and device ranges. When the dasd driver is build into the kernel,
+ * the complete list will be stored as one element of the dasd[] array.
+ * When the dasd driver is build as a module, then the list is broken into
+ * it's elements and each dasd[] entry contains one element.
+ */
+int
+dasd_parse(void)
+{
+ int rc, i;
+ char *parsestring;
+
+ rc = 0;
+ for (i = 0; i < 256; i++) {
+ if (dasd[i] == NULL)
+ break;
+ parsestring = dasd[i];
+ /* loop over the comma separated list in the parsestring */
+ while (*parsestring) {
+ parsestring = dasd_parse_next_element(parsestring);
+ if(IS_ERR(parsestring)) {
+ rc = PTR_ERR(parsestring);
+ break;
+ }
+ }
+ if (rc) {
+ DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
+ 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(char *bus_id, int features)
+{
+ struct dasd_devmap *devmap, *new, *tmp;
+ int hash;
+
+ new = (struct dasd_devmap *)
+ kmalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
+ if (!new)
+ return ERR_PTR(-ENOMEM);
+ spin_lock(&dasd_devmap_lock);
+ devmap = 0;
+ hash = dasd_hash_busid(bus_id);
+ list_for_each_entry(tmp, &dasd_hashlists[hash], list)
+ if (strncmp(tmp->bus_id, bus_id, BUS_ID_SIZE) == 0) {
+ devmap = tmp;
+ break;
+ }
+ if (!devmap) {
+ /* This bus_id is new. */
+ new->devindex = dasd_max_devindex++;
+ strncpy(new->bus_id, bus_id, BUS_ID_SIZE);
+ new->features = features;
+ new->device = 0;
+ list_add(&new->list, &dasd_hashlists[hash]);
+ devmap = new;
+ new = 0;
+ }
+ spin_unlock(&dasd_devmap_lock);
+ if (new)
+ kfree(new);
+ return devmap;
+}
+
+/*
+ * Find devmap for device with given bus_id.
+ */
+static struct dasd_devmap *
+dasd_find_busid(char *bus_id)
+{
+ struct dasd_devmap *devmap, *tmp;
+ int hash;
+
+ spin_lock(&dasd_devmap_lock);
+ 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, BUS_ID_SIZE) == 0) {
+ devmap = tmp;
+ break;
+ }
+ }
+ spin_unlock(&dasd_devmap_lock);
+ return devmap;
+}
+
+/*
+ * Check if busid has been added to the list of dasd ranges.
+ */
+int
+dasd_busid_known(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) {
+ if (devmap->device != NULL)
+ BUG();
+ 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 = 0;
+ 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(cdev->dev.bus_id);
+ if (IS_ERR(devmap))
+ devmap = dasd_add_busid(cdev->dev.bus_id,
+ 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;
+ int rc;
+
+ devmap = dasd_devmap_from_cdev(cdev);
+ if (IS_ERR(devmap))
+ return (void *) devmap;
+ cdev->dev.driver_data = devmap;
+
+ device = dasd_alloc_device();
+ if (IS_ERR(device))
+ return device;
+ atomic_set(&device->ref_count, 2);
+
+ spin_lock(&dasd_devmap_lock);
+ if (!devmap->device) {
+ devmap->device = device;
+ device->devindex = devmap->devindex;
+ if (devmap->features & DASD_FEATURE_READONLY)
+ set_bit(DASD_FLAG_RO, &device->flags);
+ else
+ clear_bit(DASD_FLAG_RO, &device->flags);
+ if (devmap->features & DASD_FEATURE_USEDIAG)
+ set_bit(DASD_FLAG_USE_DIAG, &device->flags);
+ else
+ clear_bit(DASD_FLAG_USE_DIAG, &device->flags);
+ 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);
+ }
+ return device;
+}
+
+/*
+ * 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;
+
+ /* First remove device pointer from devmap. */
+ devmap = dasd_find_busid(device->cdev->dev.bus_id);
+ if (IS_ERR(devmap))
+ BUG();
+ 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);
+
+ /* Drop ref_count by 2, one for the devmap reference and
+ * one for the passed reference. */
+ atomic_sub(2, &device->ref_count);
+
+ /* Wait for reference counter to drop to zero. */
+ wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
+
+ /* Disconnect dasd_device structure from ccw_device structure. */
+ cdev = device->cdev;
+ device->cdev = NULL;
+
+ /* Disconnect dasd_devmap structure from ccw_device structure. */
+ cdev->dev.driver_data = 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);
+}
+
+/*
+ * Return dasd_device structure associated with cdev.
+ */
+struct dasd_device *
+dasd_device_from_cdev(struct ccw_device *cdev)
+{
+ struct dasd_devmap *devmap;
+ struct dasd_device *device;
+
+ device = ERR_PTR(-ENODEV);
+ spin_lock(&dasd_devmap_lock);
+ devmap = cdev->dev.driver_data;
+ if (devmap && devmap->device) {
+ device = devmap->device;
+ dasd_get_device(device);
+ }
+ spin_unlock(&dasd_devmap_lock);
+ return device;
+}
+
+/*
+ * SECTION: files in sysfs
+ */
+
+/*
+ * readonly controls the readonly status of a dasd
+ */
+static ssize_t
+dasd_ro_show(struct device *dev, char *buf)
+{
+ struct dasd_devmap *devmap;
+ int ro_flag;
+
+ devmap = dasd_find_busid(dev->bus_id);
+ if (!IS_ERR(devmap))
+ ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
+ else
+ ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
+ return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_ro_store(struct device *dev, const char *buf, size_t count)
+{
+ struct dasd_devmap *devmap;
+ int ro_flag;
+
+ devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(devmap))
+ return PTR_ERR(devmap);
+ ro_flag = buf[0] == '1';
+ spin_lock(&dasd_devmap_lock);
+ if (ro_flag)
+ devmap->features |= DASD_FEATURE_READONLY;
+ else
+ devmap->features &= ~DASD_FEATURE_READONLY;
+ if (devmap->device) {
+ if (devmap->device->gdp)
+ set_disk_ro(devmap->device->gdp, ro_flag);
+ if (ro_flag)
+ set_bit(DASD_FLAG_RO, &devmap->device->flags);
+ else
+ clear_bit(DASD_FLAG_RO, &devmap->device->flags);
+ }
+ spin_unlock(&dasd_devmap_lock);
+ return count;
+}
+
+static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_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, char *buf)
+{
+ struct dasd_devmap *devmap;
+ int use_diag;
+
+ devmap = dasd_find_busid(dev->bus_id);
+ 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, const char *buf, size_t count)
+{
+ struct dasd_devmap *devmap;
+ ssize_t rc;
+ int use_diag;
+
+ devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(devmap))
+ return PTR_ERR(devmap);
+ use_diag = buf[0] == '1';
+ spin_lock(&dasd_devmap_lock);
+ /* Changing diag discipline flag is only allowed in offline state. */
+ rc = count;
+ if (!devmap->device) {
+ if (use_diag)
+ 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);
+
+static ssize_t
+dasd_discipline_show(struct device *dev, char *buf)
+{
+ struct dasd_devmap *devmap;
+ char *dname;
+
+ spin_lock(&dasd_devmap_lock);
+ dname = "none";
+ devmap = dev->driver_data;
+ if (devmap && devmap->device && devmap->device->discipline)
+ dname = devmap->device->discipline->name;
+ spin_unlock(&dasd_devmap_lock);
+ return snprintf(buf, PAGE_SIZE, "%s\n", dname);
+}
+
+static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
+
+static struct attribute * dasd_attrs[] = {
+ &dev_attr_readonly.attr,
+ &dev_attr_discipline.attr,
+ &dev_attr_use_diag.attr,
+ NULL,
+};
+
+static struct attribute_group dasd_attr_group = {
+ .attrs = dasd_attrs,
+};
+
+int
+dasd_add_sysfs_files(struct ccw_device *cdev)
+{
+ return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
+}
+
+void
+dasd_remove_sysfs_files(struct ccw_device *cdev)
+{
+ sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
+}
+
+
+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();
+}