xref: /openbmc/linux/drivers/s390/block/dasd_devmap.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * File...........: linux/drivers/s390/block/dasd_devmap.c
3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
5  *		    Carsten Otte <Cotte@de.ibm.com>
6  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
7  * Bugreports.to..: <Linux390@de.ibm.com>
8  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
9  *
10  * Device mapping and dasd= parameter parsing functions. All devmap
11  * functions may not be called from interrupt context. In particular
12  * dasd_get_device is a no-no from interrupt context.
13  *
14  */
15 
16 #define KMSG_COMPONENT "dasd"
17 
18 #include <linux/ctype.h>
19 #include <linux/init.h>
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 
23 #include <asm/debug.h>
24 #include <asm/uaccess.h>
25 #include <asm/ipl.h>
26 
27 /* This is ugly... */
28 #define PRINTK_HEADER "dasd_devmap:"
29 #define DASD_BUS_ID_SIZE 20
30 
31 #include "dasd_int.h"
32 
33 struct kmem_cache *dasd_page_cache;
34 EXPORT_SYMBOL_GPL(dasd_page_cache);
35 
36 /*
37  * dasd_devmap_t is used to store the features and the relation
38  * between device number and device index. To find a dasd_devmap_t
39  * that corresponds to a device number of a device index each
40  * dasd_devmap_t is added to two linked lists, one to search by
41  * the device number and one to search by the device index. As
42  * soon as big minor numbers are available the device index list
43  * can be removed since the device number will then be identical
44  * to the device index.
45  */
46 struct dasd_devmap {
47 	struct list_head list;
48 	char bus_id[DASD_BUS_ID_SIZE];
49         unsigned int devindex;
50         unsigned short features;
51 	struct dasd_device *device;
52 };
53 
54 /*
55  * Parameter parsing functions for dasd= parameter. The syntax is:
56  *   <devno>		: (0x)?[0-9a-fA-F]+
57  *   <busid>		: [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
58  *   <feature>		: ro
59  *   <feature_list>	: \(<feature>(:<feature>)*\)
60  *   <devno-range>	: <devno>(-<devno>)?<feature_list>?
61  *   <busid-range>	: <busid>(-<busid>)?<feature_list>?
62  *   <devices>		: <devno-range>|<busid-range>
63  *   <dasd_module>	: dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
64  *
65  *   <dasd>		: autodetect|probeonly|<devices>(,<devices>)*
66  */
67 
68 int dasd_probeonly =  0;	/* is true, when probeonly mode is active */
69 int dasd_autodetect = 0;	/* is true, when autodetection is active */
70 int dasd_nopav = 0;		/* is true, when PAV is disabled */
71 EXPORT_SYMBOL_GPL(dasd_nopav);
72 int dasd_nofcx;			/* disable High Performance Ficon */
73 EXPORT_SYMBOL_GPL(dasd_nofcx);
74 
75 /*
76  * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
77  * it is named 'dasd' to directly be filled by insmod with the comma separated
78  * strings when running as a module.
79  */
80 static char *dasd[256];
81 module_param_array(dasd, charp, NULL, 0);
82 
83 /*
84  * Single spinlock to protect devmap and servermap structures and lists.
85  */
86 static DEFINE_SPINLOCK(dasd_devmap_lock);
87 
88 /*
89  * Hash lists for devmap structures.
90  */
91 static struct list_head dasd_hashlists[256];
92 int dasd_max_devindex;
93 
94 static struct dasd_devmap *dasd_add_busid(const char *, int);
95 
96 static inline int
97 dasd_hash_busid(const char *bus_id)
98 {
99 	int hash, i;
100 
101 	hash = 0;
102 	for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
103 		hash += *bus_id;
104 	return hash & 0xff;
105 }
106 
107 #ifndef MODULE
108 /*
109  * The parameter parsing functions for builtin-drivers are called
110  * before kmalloc works. Store the pointers to the parameters strings
111  * into dasd[] for later processing.
112  */
113 static int __init
114 dasd_call_setup(char *str)
115 {
116 	static int count = 0;
117 
118 	if (count < 256)
119 		dasd[count++] = str;
120 	return 1;
121 }
122 
123 __setup ("dasd=", dasd_call_setup);
124 #endif	/* #ifndef MODULE */
125 
126 #define	DASD_IPLDEV	"ipldev"
127 
128 /*
129  * Read a device busid/devno from a string.
130  */
131 static int
132 
133 dasd_busid(char **str, int *id0, int *id1, int *devno)
134 {
135 	int val, old_style;
136 
137 	/* Interpret ipldev busid */
138 	if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
139 		if (ipl_info.type != IPL_TYPE_CCW) {
140 			pr_err("The IPL device is not a CCW device\n");
141 			return -EINVAL;
142 		}
143 		*id0 = 0;
144 		*id1 = ipl_info.data.ccw.dev_id.ssid;
145 		*devno = ipl_info.data.ccw.dev_id.devno;
146 		*str += strlen(DASD_IPLDEV);
147 
148 		return 0;
149 	}
150 	/* check for leading '0x' */
151 	old_style = 0;
152 	if ((*str)[0] == '0' && (*str)[1] == 'x') {
153 		*str += 2;
154 		old_style = 1;
155 	}
156 	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
157 		return -EINVAL;
158 	val = simple_strtoul(*str, str, 16);
159 	if (old_style || (*str)[0] != '.') {
160 		*id0 = *id1 = 0;
161 		if (val < 0 || val > 0xffff)
162 			return -EINVAL;
163 		*devno = val;
164 		return 0;
165 	}
166 	/* New style x.y.z busid */
167 	if (val < 0 || val > 0xff)
168 		return -EINVAL;
169 	*id0 = val;
170 	(*str)++;
171 	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
172 		return -EINVAL;
173 	val = simple_strtoul(*str, str, 16);
174 	if (val < 0 || val > 0xff || (*str)++[0] != '.')
175 		return -EINVAL;
176 	*id1 = val;
177 	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
178 		return -EINVAL;
179 	val = simple_strtoul(*str, str, 16);
180 	if (val < 0 || val > 0xffff)
181 		return -EINVAL;
182 	*devno = val;
183 	return 0;
184 }
185 
186 /*
187  * Read colon separated list of dasd features. Currently there is
188  * only one: "ro" for read-only devices. The default feature set
189  * is empty (value 0).
190  */
191 static int
192 dasd_feature_list(char *str, char **endp)
193 {
194 	int features, len, rc;
195 
196 	rc = 0;
197 	if (*str != '(') {
198 		*endp = str;
199 		return DASD_FEATURE_DEFAULT;
200 	}
201 	str++;
202 	features = 0;
203 
204 	while (1) {
205 		for (len = 0;
206 		     str[len] && str[len] != ':' && str[len] != ')'; len++);
207 		if (len == 2 && !strncmp(str, "ro", 2))
208 			features |= DASD_FEATURE_READONLY;
209 		else if (len == 4 && !strncmp(str, "diag", 4))
210 			features |= DASD_FEATURE_USEDIAG;
211 		else if (len == 3 && !strncmp(str, "raw", 3))
212 			features |= DASD_FEATURE_USERAW;
213 		else if (len == 6 && !strncmp(str, "erplog", 6))
214 			features |= DASD_FEATURE_ERPLOG;
215 		else if (len == 8 && !strncmp(str, "failfast", 8))
216 			features |= DASD_FEATURE_FAILFAST;
217 		else {
218 			pr_warning("%*s is not a supported device option\n",
219 				   len, str);
220 			rc = -EINVAL;
221 		}
222 		str += len;
223 		if (*str != ':')
224 			break;
225 		str++;
226 	}
227 	if (*str != ')') {
228 		pr_warning("A closing parenthesis ')' is missing in the "
229 			   "dasd= parameter\n");
230 		rc = -EINVAL;
231 	} else
232 		str++;
233 	*endp = str;
234 	if (rc != 0)
235 		return rc;
236 	return features;
237 }
238 
239 /*
240  * Try to match the first element on the comma separated parse string
241  * with one of the known keywords. If a keyword is found, take the approprate
242  * action and return a pointer to the residual string. If the first element
243  * could not be matched to any keyword then return an error code.
244  */
245 static char *
246 dasd_parse_keyword( char *parsestring ) {
247 
248 	char *nextcomma, *residual_str;
249 	int length;
250 
251 	nextcomma = strchr(parsestring,',');
252 	if (nextcomma) {
253 		length = nextcomma - parsestring;
254 		residual_str = nextcomma + 1;
255 	} else {
256 		length = strlen(parsestring);
257 		residual_str = parsestring + length;
258         }
259 	if (strncmp("autodetect", parsestring, length) == 0) {
260 		dasd_autodetect = 1;
261 		pr_info("The autodetection mode has been activated\n");
262                 return residual_str;
263         }
264 	if (strncmp("probeonly", parsestring, length) == 0) {
265 		dasd_probeonly = 1;
266 		pr_info("The probeonly mode has been activated\n");
267                 return residual_str;
268         }
269 	if (strncmp("nopav", parsestring, length) == 0) {
270 		if (MACHINE_IS_VM)
271 			pr_info("'nopav' is not supported on z/VM\n");
272 		else {
273 			dasd_nopav = 1;
274 			pr_info("PAV support has be deactivated\n");
275 		}
276 		return residual_str;
277 	}
278 	if (strncmp("nofcx", parsestring, length) == 0) {
279 		dasd_nofcx = 1;
280 		pr_info("High Performance FICON support has been "
281 			"deactivated\n");
282 		return residual_str;
283 	}
284 	if (strncmp("fixedbuffers", parsestring, length) == 0) {
285 		if (dasd_page_cache)
286 			return residual_str;
287 		dasd_page_cache =
288 			kmem_cache_create("dasd_page_cache", PAGE_SIZE,
289 					  PAGE_SIZE, SLAB_CACHE_DMA,
290 					  NULL);
291 		if (!dasd_page_cache)
292 			DBF_EVENT(DBF_WARNING, "%s", "Failed to create slab, "
293 				"fixed buffer mode disabled.");
294 		else
295 			DBF_EVENT(DBF_INFO, "%s",
296 				 "turning on fixed buffer mode");
297                 return residual_str;
298         }
299 	return ERR_PTR(-EINVAL);
300 }
301 
302 /*
303  * Try to interprete the first element on the comma separated parse string
304  * as a device number or a range of devices. If the interpretation is
305  * successfull, create the matching dasd_devmap entries and return a pointer
306  * to the residual string.
307  * If interpretation fails or in case of an error, return an error code.
308  */
309 static char *
310 dasd_parse_range( char *parsestring ) {
311 
312 	struct dasd_devmap *devmap;
313 	int from, from_id0, from_id1;
314 	int to, to_id0, to_id1;
315 	int features, rc;
316 	char bus_id[DASD_BUS_ID_SIZE+1], *str;
317 
318 	str = parsestring;
319 	rc = dasd_busid(&str, &from_id0, &from_id1, &from);
320 	if (rc == 0) {
321 		to = from;
322 		to_id0 = from_id0;
323 		to_id1 = from_id1;
324 		if (*str == '-') {
325 			str++;
326 			rc = dasd_busid(&str, &to_id0, &to_id1, &to);
327 		}
328 	}
329 	if (rc == 0 &&
330 	    (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
331 		rc = -EINVAL;
332 	if (rc) {
333 		pr_err("%s is not a valid device range\n", parsestring);
334 		return ERR_PTR(rc);
335 	}
336 	features = dasd_feature_list(str, &str);
337 	if (features < 0)
338 		return ERR_PTR(-EINVAL);
339 	/* each device in dasd= parameter should be set initially online */
340 	features |= DASD_FEATURE_INITIAL_ONLINE;
341 	while (from <= to) {
342 		sprintf(bus_id, "%01x.%01x.%04x",
343 			from_id0, from_id1, from++);
344 		devmap = dasd_add_busid(bus_id, features);
345 		if (IS_ERR(devmap))
346 			return (char *)devmap;
347 	}
348 	if (*str == ',')
349 		return str + 1;
350 	if (*str == '\0')
351 		return str;
352 	pr_warning("The dasd= parameter value %s has an invalid ending\n",
353 		   str);
354 	return ERR_PTR(-EINVAL);
355 }
356 
357 static char *
358 dasd_parse_next_element( char *parsestring ) {
359 	char * residual_str;
360 	residual_str = dasd_parse_keyword(parsestring);
361 	if (!IS_ERR(residual_str))
362 		return residual_str;
363 	residual_str = dasd_parse_range(parsestring);
364 	return residual_str;
365 }
366 
367 /*
368  * Parse parameters stored in dasd[]
369  * The 'dasd=...' parameter allows to specify a comma separated list of
370  * keywords and device ranges. When the dasd driver is build into the kernel,
371  * the complete list will be stored as one element of the dasd[] array.
372  * When the dasd driver is build as a module, then the list is broken into
373  * it's elements and each dasd[] entry contains one element.
374  */
375 int
376 dasd_parse(void)
377 {
378 	int rc, i;
379 	char *parsestring;
380 
381 	rc = 0;
382 	for (i = 0; i < 256; i++) {
383 		if (dasd[i] == NULL)
384 			break;
385 		parsestring = dasd[i];
386 		/* loop over the comma separated list in the parsestring */
387 		while (*parsestring) {
388 			parsestring = dasd_parse_next_element(parsestring);
389 			if(IS_ERR(parsestring)) {
390 				rc = PTR_ERR(parsestring);
391 				break;
392 			}
393 		}
394 		if (rc) {
395 			DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
396 			break;
397 		}
398 	}
399 	return rc;
400 }
401 
402 /*
403  * Add a devmap for the device specified by busid. It is possible that
404  * the devmap already exists (dasd= parameter). The order of the devices
405  * added through this function will define the kdevs for the individual
406  * devices.
407  */
408 static struct dasd_devmap *
409 dasd_add_busid(const char *bus_id, int features)
410 {
411 	struct dasd_devmap *devmap, *new, *tmp;
412 	int hash;
413 
414 	new = (struct dasd_devmap *)
415 		kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
416 	if (!new)
417 		return ERR_PTR(-ENOMEM);
418 	spin_lock(&dasd_devmap_lock);
419 	devmap = NULL;
420 	hash = dasd_hash_busid(bus_id);
421 	list_for_each_entry(tmp, &dasd_hashlists[hash], list)
422 		if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
423 			devmap = tmp;
424 			break;
425 		}
426 	if (!devmap) {
427 		/* This bus_id is new. */
428 		new->devindex = dasd_max_devindex++;
429 		strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
430 		new->features = features;
431 		new->device = NULL;
432 		list_add(&new->list, &dasd_hashlists[hash]);
433 		devmap = new;
434 		new = NULL;
435 	}
436 	spin_unlock(&dasd_devmap_lock);
437 	kfree(new);
438 	return devmap;
439 }
440 
441 /*
442  * Find devmap for device with given bus_id.
443  */
444 static struct dasd_devmap *
445 dasd_find_busid(const char *bus_id)
446 {
447 	struct dasd_devmap *devmap, *tmp;
448 	int hash;
449 
450 	spin_lock(&dasd_devmap_lock);
451 	devmap = ERR_PTR(-ENODEV);
452 	hash = dasd_hash_busid(bus_id);
453 	list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
454 		if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
455 			devmap = tmp;
456 			break;
457 		}
458 	}
459 	spin_unlock(&dasd_devmap_lock);
460 	return devmap;
461 }
462 
463 /*
464  * Check if busid has been added to the list of dasd ranges.
465  */
466 int
467 dasd_busid_known(const char *bus_id)
468 {
469 	return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
470 }
471 
472 /*
473  * Forget all about the device numbers added so far.
474  * This may only be called at module unload or system shutdown.
475  */
476 static void
477 dasd_forget_ranges(void)
478 {
479 	struct dasd_devmap *devmap, *n;
480 	int i;
481 
482 	spin_lock(&dasd_devmap_lock);
483 	for (i = 0; i < 256; i++) {
484 		list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
485 			BUG_ON(devmap->device != NULL);
486 			list_del(&devmap->list);
487 			kfree(devmap);
488 		}
489 	}
490 	spin_unlock(&dasd_devmap_lock);
491 }
492 
493 /*
494  * Find the device struct by its device index.
495  */
496 struct dasd_device *
497 dasd_device_from_devindex(int devindex)
498 {
499 	struct dasd_devmap *devmap, *tmp;
500 	struct dasd_device *device;
501 	int i;
502 
503 	spin_lock(&dasd_devmap_lock);
504 	devmap = NULL;
505 	for (i = 0; (i < 256) && !devmap; i++)
506 		list_for_each_entry(tmp, &dasd_hashlists[i], list)
507 			if (tmp->devindex == devindex) {
508 				/* Found the devmap for the device. */
509 				devmap = tmp;
510 				break;
511 			}
512 	if (devmap && devmap->device) {
513 		device = devmap->device;
514 		dasd_get_device(device);
515 	} else
516 		device = ERR_PTR(-ENODEV);
517 	spin_unlock(&dasd_devmap_lock);
518 	return device;
519 }
520 
521 /*
522  * Return devmap for cdev. If no devmap exists yet, create one and
523  * connect it to the cdev.
524  */
525 static struct dasd_devmap *
526 dasd_devmap_from_cdev(struct ccw_device *cdev)
527 {
528 	struct dasd_devmap *devmap;
529 
530 	devmap = dasd_find_busid(dev_name(&cdev->dev));
531 	if (IS_ERR(devmap))
532 		devmap = dasd_add_busid(dev_name(&cdev->dev),
533 					DASD_FEATURE_DEFAULT);
534 	return devmap;
535 }
536 
537 /*
538  * Create a dasd device structure for cdev.
539  */
540 struct dasd_device *
541 dasd_create_device(struct ccw_device *cdev)
542 {
543 	struct dasd_devmap *devmap;
544 	struct dasd_device *device;
545 	unsigned long flags;
546 	int rc;
547 
548 	devmap = dasd_devmap_from_cdev(cdev);
549 	if (IS_ERR(devmap))
550 		return (void *) devmap;
551 
552 	device = dasd_alloc_device();
553 	if (IS_ERR(device))
554 		return device;
555 	atomic_set(&device->ref_count, 3);
556 
557 	spin_lock(&dasd_devmap_lock);
558 	if (!devmap->device) {
559 		devmap->device = device;
560 		device->devindex = devmap->devindex;
561 		device->features = devmap->features;
562 		get_device(&cdev->dev);
563 		device->cdev = cdev;
564 		rc = 0;
565 	} else
566 		/* Someone else was faster. */
567 		rc = -EBUSY;
568 	spin_unlock(&dasd_devmap_lock);
569 
570 	if (rc) {
571 		dasd_free_device(device);
572 		return ERR_PTR(rc);
573 	}
574 
575 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
576 	dev_set_drvdata(&cdev->dev, device);
577 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
578 
579 	return device;
580 }
581 
582 /*
583  * Wait queue for dasd_delete_device waits.
584  */
585 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
586 
587 /*
588  * Remove a dasd device structure. The passed referenced
589  * is destroyed.
590  */
591 void
592 dasd_delete_device(struct dasd_device *device)
593 {
594 	struct ccw_device *cdev;
595 	struct dasd_devmap *devmap;
596 	unsigned long flags;
597 
598 	/* First remove device pointer from devmap. */
599 	devmap = dasd_find_busid(dev_name(&device->cdev->dev));
600 	BUG_ON(IS_ERR(devmap));
601 	spin_lock(&dasd_devmap_lock);
602 	if (devmap->device != device) {
603 		spin_unlock(&dasd_devmap_lock);
604 		dasd_put_device(device);
605 		return;
606 	}
607 	devmap->device = NULL;
608 	spin_unlock(&dasd_devmap_lock);
609 
610 	/* Disconnect dasd_device structure from ccw_device structure. */
611 	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
612 	dev_set_drvdata(&device->cdev->dev, NULL);
613 	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
614 
615 	/*
616 	 * Drop ref_count by 3, one for the devmap reference, one for
617 	 * the cdev reference and one for the passed reference.
618 	 */
619 	atomic_sub(3, &device->ref_count);
620 
621 	/* Wait for reference counter to drop to zero. */
622 	wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
623 
624 	/* Disconnect dasd_device structure from ccw_device structure. */
625 	cdev = device->cdev;
626 	device->cdev = NULL;
627 
628 	/* Put ccw_device structure. */
629 	put_device(&cdev->dev);
630 
631 	/* Now the device structure can be freed. */
632 	dasd_free_device(device);
633 }
634 
635 /*
636  * Reference counter dropped to zero. Wake up waiter
637  * in dasd_delete_device.
638  */
639 void
640 dasd_put_device_wake(struct dasd_device *device)
641 {
642 	wake_up(&dasd_delete_wq);
643 }
644 EXPORT_SYMBOL_GPL(dasd_put_device_wake);
645 
646 /*
647  * Return dasd_device structure associated with cdev.
648  * This function needs to be called with the ccw device
649  * lock held. It can be used from interrupt context.
650  */
651 struct dasd_device *
652 dasd_device_from_cdev_locked(struct ccw_device *cdev)
653 {
654 	struct dasd_device *device = dev_get_drvdata(&cdev->dev);
655 
656 	if (!device)
657 		return ERR_PTR(-ENODEV);
658 	dasd_get_device(device);
659 	return device;
660 }
661 
662 /*
663  * Return dasd_device structure associated with cdev.
664  */
665 struct dasd_device *
666 dasd_device_from_cdev(struct ccw_device *cdev)
667 {
668 	struct dasd_device *device;
669 	unsigned long flags;
670 
671 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
672 	device = dasd_device_from_cdev_locked(cdev);
673 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
674 	return device;
675 }
676 
677 /*
678  * SECTION: files in sysfs
679  */
680 
681 /*
682  * failfast controls the behaviour, if no path is available
683  */
684 static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
685 			    char *buf)
686 {
687 	struct dasd_devmap *devmap;
688 	int ff_flag;
689 
690 	devmap = dasd_find_busid(dev_name(dev));
691 	if (!IS_ERR(devmap))
692 		ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
693 	else
694 		ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
695 	return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
696 }
697 
698 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
699 	      const char *buf, size_t count)
700 {
701 	struct dasd_devmap *devmap;
702 	int val;
703 	char *endp;
704 
705 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
706 	if (IS_ERR(devmap))
707 		return PTR_ERR(devmap);
708 
709 	val = simple_strtoul(buf, &endp, 0);
710 	if (((endp + 1) < (buf + count)) || (val > 1))
711 		return -EINVAL;
712 
713 	spin_lock(&dasd_devmap_lock);
714 	if (val)
715 		devmap->features |= DASD_FEATURE_FAILFAST;
716 	else
717 		devmap->features &= ~DASD_FEATURE_FAILFAST;
718 	if (devmap->device)
719 		devmap->device->features = devmap->features;
720 	spin_unlock(&dasd_devmap_lock);
721 	return count;
722 }
723 
724 static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
725 
726 /*
727  * readonly controls the readonly status of a dasd
728  */
729 static ssize_t
730 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
731 {
732 	struct dasd_devmap *devmap;
733 	int ro_flag;
734 
735 	devmap = dasd_find_busid(dev_name(dev));
736 	if (!IS_ERR(devmap))
737 		ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
738 	else
739 		ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
740 	return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
741 }
742 
743 static ssize_t
744 dasd_ro_store(struct device *dev, struct device_attribute *attr,
745 	      const char *buf, size_t count)
746 {
747 	struct dasd_devmap *devmap;
748 	struct dasd_device *device;
749 	int val;
750 	char *endp;
751 
752 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
753 	if (IS_ERR(devmap))
754 		return PTR_ERR(devmap);
755 
756 	val = simple_strtoul(buf, &endp, 0);
757 	if (((endp + 1) < (buf + count)) || (val > 1))
758 		return -EINVAL;
759 
760 	spin_lock(&dasd_devmap_lock);
761 	if (val)
762 		devmap->features |= DASD_FEATURE_READONLY;
763 	else
764 		devmap->features &= ~DASD_FEATURE_READONLY;
765 	device = devmap->device;
766 	if (device) {
767 		device->features = devmap->features;
768 		val = val || test_bit(DASD_FLAG_DEVICE_RO, &device->flags);
769 	}
770 	spin_unlock(&dasd_devmap_lock);
771 	if (device && device->block && device->block->gdp)
772 		set_disk_ro(device->block->gdp, val);
773 	return count;
774 }
775 
776 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
777 /*
778  * erplog controls the logging of ERP related data
779  * (e.g. failing channel programs).
780  */
781 static ssize_t
782 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
783 {
784 	struct dasd_devmap *devmap;
785 	int erplog;
786 
787 	devmap = dasd_find_busid(dev_name(dev));
788 	if (!IS_ERR(devmap))
789 		erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
790 	else
791 		erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
792 	return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
793 }
794 
795 static ssize_t
796 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
797 	      const char *buf, size_t count)
798 {
799 	struct dasd_devmap *devmap;
800 	int val;
801 	char *endp;
802 
803 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
804 	if (IS_ERR(devmap))
805 		return PTR_ERR(devmap);
806 
807 	val = simple_strtoul(buf, &endp, 0);
808 	if (((endp + 1) < (buf + count)) || (val > 1))
809 		return -EINVAL;
810 
811 	spin_lock(&dasd_devmap_lock);
812 	if (val)
813 		devmap->features |= DASD_FEATURE_ERPLOG;
814 	else
815 		devmap->features &= ~DASD_FEATURE_ERPLOG;
816 	if (devmap->device)
817 		devmap->device->features = devmap->features;
818 	spin_unlock(&dasd_devmap_lock);
819 	return count;
820 }
821 
822 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
823 
824 /*
825  * use_diag controls whether the driver should use diag rather than ssch
826  * to talk to the device
827  */
828 static ssize_t
829 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
830 {
831 	struct dasd_devmap *devmap;
832 	int use_diag;
833 
834 	devmap = dasd_find_busid(dev_name(dev));
835 	if (!IS_ERR(devmap))
836 		use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
837 	else
838 		use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
839 	return sprintf(buf, use_diag ? "1\n" : "0\n");
840 }
841 
842 static ssize_t
843 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
844 		    const char *buf, size_t count)
845 {
846 	struct dasd_devmap *devmap;
847 	ssize_t rc;
848 	int val;
849 	char *endp;
850 
851 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
852 	if (IS_ERR(devmap))
853 		return PTR_ERR(devmap);
854 
855 	val = simple_strtoul(buf, &endp, 0);
856 	if (((endp + 1) < (buf + count)) || (val > 1))
857 		return -EINVAL;
858 
859 	spin_lock(&dasd_devmap_lock);
860 	/* Changing diag discipline flag is only allowed in offline state. */
861 	rc = count;
862 	if (!devmap->device && !(devmap->features & DASD_FEATURE_USERAW)) {
863 		if (val)
864 			devmap->features |= DASD_FEATURE_USEDIAG;
865 		else
866 			devmap->features &= ~DASD_FEATURE_USEDIAG;
867 	} else
868 		rc = -EPERM;
869 	spin_unlock(&dasd_devmap_lock);
870 	return rc;
871 }
872 
873 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
874 
875 /*
876  * use_raw controls whether the driver should give access to raw eckd data or
877  * operate in standard mode
878  */
879 static ssize_t
880 dasd_use_raw_show(struct device *dev, struct device_attribute *attr, char *buf)
881 {
882 	struct dasd_devmap *devmap;
883 	int use_raw;
884 
885 	devmap = dasd_find_busid(dev_name(dev));
886 	if (!IS_ERR(devmap))
887 		use_raw = (devmap->features & DASD_FEATURE_USERAW) != 0;
888 	else
889 		use_raw = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USERAW) != 0;
890 	return sprintf(buf, use_raw ? "1\n" : "0\n");
891 }
892 
893 static ssize_t
894 dasd_use_raw_store(struct device *dev, struct device_attribute *attr,
895 		    const char *buf, size_t count)
896 {
897 	struct dasd_devmap *devmap;
898 	ssize_t rc;
899 	unsigned long val;
900 
901 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
902 	if (IS_ERR(devmap))
903 		return PTR_ERR(devmap);
904 
905 	if ((strict_strtoul(buf, 10, &val) != 0) || val > 1)
906 		return -EINVAL;
907 
908 	spin_lock(&dasd_devmap_lock);
909 	/* Changing diag discipline flag is only allowed in offline state. */
910 	rc = count;
911 	if (!devmap->device && !(devmap->features & DASD_FEATURE_USEDIAG)) {
912 		if (val)
913 			devmap->features |= DASD_FEATURE_USERAW;
914 		else
915 			devmap->features &= ~DASD_FEATURE_USERAW;
916 	} else
917 		rc = -EPERM;
918 	spin_unlock(&dasd_devmap_lock);
919 	return rc;
920 }
921 
922 static DEVICE_ATTR(raw_track_access, 0644, dasd_use_raw_show,
923 		   dasd_use_raw_store);
924 
925 static ssize_t
926 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
927 		     char *buf)
928 {
929 	struct dasd_device *device;
930 	ssize_t len;
931 
932 	device = dasd_device_from_cdev(to_ccwdev(dev));
933 	if (IS_ERR(device))
934 		goto out;
935 	else if (!device->discipline) {
936 		dasd_put_device(device);
937 		goto out;
938 	} else {
939 		len = snprintf(buf, PAGE_SIZE, "%s\n",
940 			       device->discipline->name);
941 		dasd_put_device(device);
942 		return len;
943 	}
944 out:
945 	len = snprintf(buf, PAGE_SIZE, "none\n");
946 	return len;
947 }
948 
949 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
950 
951 static ssize_t
952 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
953 		     char *buf)
954 {
955 	struct dasd_device *device;
956 	ssize_t len;
957 
958 	device = dasd_device_from_cdev(to_ccwdev(dev));
959 	if (!IS_ERR(device)) {
960 		switch (device->state) {
961 		case DASD_STATE_NEW:
962 			len = snprintf(buf, PAGE_SIZE, "new\n");
963 			break;
964 		case DASD_STATE_KNOWN:
965 			len = snprintf(buf, PAGE_SIZE, "detected\n");
966 			break;
967 		case DASD_STATE_BASIC:
968 			len = snprintf(buf, PAGE_SIZE, "basic\n");
969 			break;
970 		case DASD_STATE_UNFMT:
971 			len = snprintf(buf, PAGE_SIZE, "unformatted\n");
972 			break;
973 		case DASD_STATE_READY:
974 			len = snprintf(buf, PAGE_SIZE, "ready\n");
975 			break;
976 		case DASD_STATE_ONLINE:
977 			len = snprintf(buf, PAGE_SIZE, "online\n");
978 			break;
979 		default:
980 			len = snprintf(buf, PAGE_SIZE, "no stat\n");
981 			break;
982 		}
983 		dasd_put_device(device);
984 	} else
985 		len = snprintf(buf, PAGE_SIZE, "unknown\n");
986 	return len;
987 }
988 
989 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
990 
991 static ssize_t dasd_alias_show(struct device *dev,
992 			       struct device_attribute *attr, char *buf)
993 {
994 	struct dasd_device *device;
995 	struct dasd_uid uid;
996 
997 	device = dasd_device_from_cdev(to_ccwdev(dev));
998 	if (IS_ERR(device))
999 		return sprintf(buf, "0\n");
1000 
1001 	if (device->discipline && device->discipline->get_uid &&
1002 	    !device->discipline->get_uid(device, &uid)) {
1003 		if (uid.type == UA_BASE_PAV_ALIAS ||
1004 		    uid.type == UA_HYPER_PAV_ALIAS) {
1005 			dasd_put_device(device);
1006 			return sprintf(buf, "1\n");
1007 		}
1008 	}
1009 	dasd_put_device(device);
1010 
1011 	return sprintf(buf, "0\n");
1012 }
1013 
1014 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
1015 
1016 static ssize_t dasd_vendor_show(struct device *dev,
1017 				struct device_attribute *attr, char *buf)
1018 {
1019 	struct dasd_device *device;
1020 	struct dasd_uid uid;
1021 	char *vendor;
1022 
1023 	device = dasd_device_from_cdev(to_ccwdev(dev));
1024 	vendor = "";
1025 	if (IS_ERR(device))
1026 		return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
1027 
1028 	if (device->discipline && device->discipline->get_uid &&
1029 	    !device->discipline->get_uid(device, &uid))
1030 			vendor = uid.vendor;
1031 
1032 	dasd_put_device(device);
1033 
1034 	return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
1035 }
1036 
1037 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
1038 
1039 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
1040 		     /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
1041 		     /* vduit */ 32 + 1)
1042 
1043 static ssize_t
1044 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
1045 {
1046 	struct dasd_device *device;
1047 	struct dasd_uid uid;
1048 	char uid_string[UID_STRLEN];
1049 	char ua_string[3];
1050 
1051 	device = dasd_device_from_cdev(to_ccwdev(dev));
1052 	uid_string[0] = 0;
1053 	if (IS_ERR(device))
1054 		return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1055 
1056 	if (device->discipline && device->discipline->get_uid &&
1057 	    !device->discipline->get_uid(device, &uid)) {
1058 		switch (uid.type) {
1059 		case UA_BASE_DEVICE:
1060 			snprintf(ua_string, sizeof(ua_string), "%02x",
1061 				 uid.real_unit_addr);
1062 			break;
1063 		case UA_BASE_PAV_ALIAS:
1064 			snprintf(ua_string, sizeof(ua_string), "%02x",
1065 				 uid.base_unit_addr);
1066 			break;
1067 		case UA_HYPER_PAV_ALIAS:
1068 			snprintf(ua_string, sizeof(ua_string), "xx");
1069 			break;
1070 		default:
1071 			/* should not happen, treat like base device */
1072 			snprintf(ua_string, sizeof(ua_string), "%02x",
1073 				 uid.real_unit_addr);
1074 			break;
1075 		}
1076 
1077 		if (strlen(uid.vduit) > 0)
1078 			snprintf(uid_string, sizeof(uid_string),
1079 				 "%s.%s.%04x.%s.%s",
1080 				 uid.vendor, uid.serial, uid.ssid, ua_string,
1081 				 uid.vduit);
1082 		else
1083 			snprintf(uid_string, sizeof(uid_string),
1084 				 "%s.%s.%04x.%s",
1085 				 uid.vendor, uid.serial, uid.ssid, ua_string);
1086 	}
1087 	dasd_put_device(device);
1088 
1089 	return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1090 }
1091 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
1092 
1093 /*
1094  * extended error-reporting
1095  */
1096 static ssize_t
1097 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
1098 {
1099 	struct dasd_devmap *devmap;
1100 	int eer_flag;
1101 
1102 	devmap = dasd_find_busid(dev_name(dev));
1103 	if (!IS_ERR(devmap) && devmap->device)
1104 		eer_flag = dasd_eer_enabled(devmap->device);
1105 	else
1106 		eer_flag = 0;
1107 	return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
1108 }
1109 
1110 static ssize_t
1111 dasd_eer_store(struct device *dev, struct device_attribute *attr,
1112 	       const char *buf, size_t count)
1113 {
1114 	struct dasd_devmap *devmap;
1115 	int val, rc;
1116 	char *endp;
1117 
1118 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1119 	if (IS_ERR(devmap))
1120 		return PTR_ERR(devmap);
1121 	if (!devmap->device)
1122 		return -ENODEV;
1123 
1124 	val = simple_strtoul(buf, &endp, 0);
1125 	if (((endp + 1) < (buf + count)) || (val > 1))
1126 		return -EINVAL;
1127 
1128 	if (val) {
1129 		rc = dasd_eer_enable(devmap->device);
1130 		if (rc)
1131 			return rc;
1132 	} else
1133 		dasd_eer_disable(devmap->device);
1134 	return count;
1135 }
1136 
1137 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1138 
1139 /*
1140  * expiration time for default requests
1141  */
1142 static ssize_t
1143 dasd_expires_show(struct device *dev, struct device_attribute *attr, char *buf)
1144 {
1145 	struct dasd_device *device;
1146 	int len;
1147 
1148 	device = dasd_device_from_cdev(to_ccwdev(dev));
1149 	if (IS_ERR(device))
1150 		return -ENODEV;
1151 	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_expires);
1152 	dasd_put_device(device);
1153 	return len;
1154 }
1155 
1156 static ssize_t
1157 dasd_expires_store(struct device *dev, struct device_attribute *attr,
1158 	       const char *buf, size_t count)
1159 {
1160 	struct dasd_device *device;
1161 	unsigned long val;
1162 
1163 	device = dasd_device_from_cdev(to_ccwdev(dev));
1164 	if (IS_ERR(device))
1165 		return -ENODEV;
1166 
1167 	if ((strict_strtoul(buf, 10, &val) != 0) ||
1168 	    (val > DASD_EXPIRES_MAX) || val == 0) {
1169 		dasd_put_device(device);
1170 		return -EINVAL;
1171 	}
1172 
1173 	if (val)
1174 		device->default_expires = val;
1175 
1176 	dasd_put_device(device);
1177 	return count;
1178 }
1179 
1180 static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store);
1181 
1182 static ssize_t dasd_reservation_policy_show(struct device *dev,
1183 					    struct device_attribute *attr,
1184 					    char *buf)
1185 {
1186 	struct dasd_devmap *devmap;
1187 	int rc = 0;
1188 
1189 	devmap = dasd_find_busid(dev_name(dev));
1190 	if (IS_ERR(devmap)) {
1191 		rc = snprintf(buf, PAGE_SIZE, "ignore\n");
1192 	} else {
1193 		spin_lock(&dasd_devmap_lock);
1194 		if (devmap->features & DASD_FEATURE_FAILONSLCK)
1195 			rc = snprintf(buf, PAGE_SIZE, "fail\n");
1196 		else
1197 			rc = snprintf(buf, PAGE_SIZE, "ignore\n");
1198 		spin_unlock(&dasd_devmap_lock);
1199 	}
1200 	return rc;
1201 }
1202 
1203 static ssize_t dasd_reservation_policy_store(struct device *dev,
1204 					     struct device_attribute *attr,
1205 					     const char *buf, size_t count)
1206 {
1207 	struct dasd_devmap *devmap;
1208 	int rc;
1209 
1210 	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1211 	if (IS_ERR(devmap))
1212 		return PTR_ERR(devmap);
1213 	rc = 0;
1214 	spin_lock(&dasd_devmap_lock);
1215 	if (sysfs_streq("ignore", buf))
1216 		devmap->features &= ~DASD_FEATURE_FAILONSLCK;
1217 	else if (sysfs_streq("fail", buf))
1218 		devmap->features |= DASD_FEATURE_FAILONSLCK;
1219 	else
1220 		rc = -EINVAL;
1221 	if (devmap->device)
1222 		devmap->device->features = devmap->features;
1223 	spin_unlock(&dasd_devmap_lock);
1224 	if (rc)
1225 		return rc;
1226 	else
1227 		return count;
1228 }
1229 
1230 static DEVICE_ATTR(reservation_policy, 0644,
1231 		   dasd_reservation_policy_show, dasd_reservation_policy_store);
1232 
1233 static ssize_t dasd_reservation_state_show(struct device *dev,
1234 					   struct device_attribute *attr,
1235 					   char *buf)
1236 {
1237 	struct dasd_device *device;
1238 	int rc = 0;
1239 
1240 	device = dasd_device_from_cdev(to_ccwdev(dev));
1241 	if (IS_ERR(device))
1242 		return snprintf(buf, PAGE_SIZE, "none\n");
1243 
1244 	if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags))
1245 		rc = snprintf(buf, PAGE_SIZE, "reserved\n");
1246 	else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags))
1247 		rc = snprintf(buf, PAGE_SIZE, "lost\n");
1248 	else
1249 		rc = snprintf(buf, PAGE_SIZE, "none\n");
1250 	dasd_put_device(device);
1251 	return rc;
1252 }
1253 
1254 static ssize_t dasd_reservation_state_store(struct device *dev,
1255 					    struct device_attribute *attr,
1256 					    const char *buf, size_t count)
1257 {
1258 	struct dasd_device *device;
1259 	int rc = 0;
1260 
1261 	device = dasd_device_from_cdev(to_ccwdev(dev));
1262 	if (IS_ERR(device))
1263 		return -ENODEV;
1264 	if (sysfs_streq("reset", buf))
1265 		clear_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
1266 	else
1267 		rc = -EINVAL;
1268 	dasd_put_device(device);
1269 
1270 	if (rc)
1271 		return rc;
1272 	else
1273 		return count;
1274 }
1275 
1276 static DEVICE_ATTR(last_known_reservation_state, 0644,
1277 		   dasd_reservation_state_show, dasd_reservation_state_store);
1278 
1279 static struct attribute * dasd_attrs[] = {
1280 	&dev_attr_readonly.attr,
1281 	&dev_attr_discipline.attr,
1282 	&dev_attr_status.attr,
1283 	&dev_attr_alias.attr,
1284 	&dev_attr_vendor.attr,
1285 	&dev_attr_uid.attr,
1286 	&dev_attr_use_diag.attr,
1287 	&dev_attr_raw_track_access.attr,
1288 	&dev_attr_eer_enabled.attr,
1289 	&dev_attr_erplog.attr,
1290 	&dev_attr_failfast.attr,
1291 	&dev_attr_expires.attr,
1292 	&dev_attr_reservation_policy.attr,
1293 	&dev_attr_last_known_reservation_state.attr,
1294 	NULL,
1295 };
1296 
1297 static struct attribute_group dasd_attr_group = {
1298 	.attrs = dasd_attrs,
1299 };
1300 
1301 /*
1302  * Return value of the specified feature.
1303  */
1304 int
1305 dasd_get_feature(struct ccw_device *cdev, int feature)
1306 {
1307 	struct dasd_devmap *devmap;
1308 
1309 	devmap = dasd_find_busid(dev_name(&cdev->dev));
1310 	if (IS_ERR(devmap))
1311 		return PTR_ERR(devmap);
1312 
1313 	return ((devmap->features & feature) != 0);
1314 }
1315 
1316 /*
1317  * Set / reset given feature.
1318  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1319  */
1320 int
1321 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1322 {
1323 	struct dasd_devmap *devmap;
1324 
1325 	devmap = dasd_find_busid(dev_name(&cdev->dev));
1326 	if (IS_ERR(devmap))
1327 		return PTR_ERR(devmap);
1328 
1329 	spin_lock(&dasd_devmap_lock);
1330 	if (flag)
1331 		devmap->features |= feature;
1332 	else
1333 		devmap->features &= ~feature;
1334 	if (devmap->device)
1335 		devmap->device->features = devmap->features;
1336 	spin_unlock(&dasd_devmap_lock);
1337 	return 0;
1338 }
1339 
1340 
1341 int
1342 dasd_add_sysfs_files(struct ccw_device *cdev)
1343 {
1344 	return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1345 }
1346 
1347 void
1348 dasd_remove_sysfs_files(struct ccw_device *cdev)
1349 {
1350 	sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1351 }
1352 
1353 
1354 int
1355 dasd_devmap_init(void)
1356 {
1357 	int i;
1358 
1359 	/* Initialize devmap structures. */
1360 	dasd_max_devindex = 0;
1361 	for (i = 0; i < 256; i++)
1362 		INIT_LIST_HEAD(&dasd_hashlists[i]);
1363 	return 0;
1364 }
1365 
1366 void
1367 dasd_devmap_exit(void)
1368 {
1369 	dasd_forget_ranges();
1370 }
1371