Merge branch 'drm-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / drivers / s390 / block / dasd_devmap.c
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 #include <linux/ctype.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19
20 #include <asm/debug.h>
21 #include <asm/uaccess.h>
22 #include <asm/ipl.h>
23
24 /* This is ugly... */
25 #define PRINTK_HEADER "dasd_devmap:"
26 #define DASD_BUS_ID_SIZE 20
27
28 #include "dasd_int.h"
29
30 struct kmem_cache *dasd_page_cache;
31 EXPORT_SYMBOL_GPL(dasd_page_cache);
32
33 /*
34  * dasd_devmap_t is used to store the features and the relation
35  * between device number and device index. To find a dasd_devmap_t
36  * that corresponds to a device number of a device index each
37  * dasd_devmap_t is added to two linked lists, one to search by
38  * the device number and one to search by the device index. As
39  * soon as big minor numbers are available the device index list
40  * can be removed since the device number will then be identical
41  * to the device index.
42  */
43 struct dasd_devmap {
44         struct list_head list;
45         char bus_id[DASD_BUS_ID_SIZE];
46         unsigned int devindex;
47         unsigned short features;
48         struct dasd_device *device;
49         struct dasd_uid uid;
50 };
51
52 /*
53  * Parameter parsing functions for dasd= parameter. The syntax is:
54  *   <devno>            : (0x)?[0-9a-fA-F]+
55  *   <busid>            : [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
56  *   <feature>          : ro
57  *   <feature_list>     : \(<feature>(:<feature>)*\)
58  *   <devno-range>      : <devno>(-<devno>)?<feature_list>?
59  *   <busid-range>      : <busid>(-<busid>)?<feature_list>?
60  *   <devices>          : <devno-range>|<busid-range>
61  *   <dasd_module>      : dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
62  *
63  *   <dasd>             : autodetect|probeonly|<devices>(,<devices>)*
64  */
65
66 int dasd_probeonly =  0;        /* is true, when probeonly mode is active */
67 int dasd_autodetect = 0;        /* is true, when autodetection is active */
68 int dasd_nopav = 0;             /* is true, when PAV is disabled */
69 EXPORT_SYMBOL_GPL(dasd_nopav);
70
71 /*
72  * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
73  * it is named 'dasd' to directly be filled by insmod with the comma separated
74  * strings when running as a module.
75  */
76 static char *dasd[256];
77 module_param_array(dasd, charp, NULL, 0);
78
79 /*
80  * Single spinlock to protect devmap and servermap structures and lists.
81  */
82 static DEFINE_SPINLOCK(dasd_devmap_lock);
83
84 /*
85  * Hash lists for devmap structures.
86  */
87 static struct list_head dasd_hashlists[256];
88 int dasd_max_devindex;
89
90 static struct dasd_devmap *dasd_add_busid(const char *, int);
91
92 static inline int
93 dasd_hash_busid(const char *bus_id)
94 {
95         int hash, i;
96
97         hash = 0;
98         for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
99                 hash += *bus_id;
100         return hash & 0xff;
101 }
102
103 #ifndef MODULE
104 /*
105  * The parameter parsing functions for builtin-drivers are called
106  * before kmalloc works. Store the pointers to the parameters strings
107  * into dasd[] for later processing.
108  */
109 static int __init
110 dasd_call_setup(char *str)
111 {
112         static int count = 0;
113
114         if (count < 256)
115                 dasd[count++] = str;
116         return 1;
117 }
118
119 __setup ("dasd=", dasd_call_setup);
120 #endif  /* #ifndef MODULE */
121
122 #define DASD_IPLDEV     "ipldev"
123
124 /*
125  * Read a device busid/devno from a string.
126  */
127 static int
128 dasd_busid(char **str, int *id0, int *id1, int *devno)
129 {
130         int val, old_style;
131
132         /* Interpret ipldev busid */
133         if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
134                 if (ipl_info.type != IPL_TYPE_CCW) {
135                         MESSAGE(KERN_ERR, "%s", "ipl device is not a ccw "
136                                 "device");
137                         return -EINVAL;
138                 }
139                 *id0 = 0;
140                 *id1 = ipl_info.data.ccw.dev_id.ssid;
141                 *devno = ipl_info.data.ccw.dev_id.devno;
142                 *str += strlen(DASD_IPLDEV);
143
144                 return 0;
145         }
146         /* check for leading '0x' */
147         old_style = 0;
148         if ((*str)[0] == '0' && (*str)[1] == 'x') {
149                 *str += 2;
150                 old_style = 1;
151         }
152         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
153                 return -EINVAL;
154         val = simple_strtoul(*str, str, 16);
155         if (old_style || (*str)[0] != '.') {
156                 *id0 = *id1 = 0;
157                 if (val < 0 || val > 0xffff)
158                         return -EINVAL;
159                 *devno = val;
160                 return 0;
161         }
162         /* New style x.y.z busid */
163         if (val < 0 || val > 0xff)
164                 return -EINVAL;
165         *id0 = val;
166         (*str)++;
167         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
168                 return -EINVAL;
169         val = simple_strtoul(*str, str, 16);
170         if (val < 0 || val > 0xff || (*str)++[0] != '.')
171                 return -EINVAL;
172         *id1 = val;
173         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
174                 return -EINVAL;
175         val = simple_strtoul(*str, str, 16);
176         if (val < 0 || val > 0xffff)
177                 return -EINVAL;
178         *devno = val;
179         return 0;
180 }
181
182 /*
183  * Read colon separated list of dasd features. Currently there is
184  * only one: "ro" for read-only devices. The default feature set
185  * is empty (value 0).
186  */
187 static int
188 dasd_feature_list(char *str, char **endp)
189 {
190         int features, len, rc;
191
192         rc = 0;
193         if (*str != '(') {
194                 *endp = str;
195                 return DASD_FEATURE_DEFAULT;
196         }
197         str++;
198         features = 0;
199
200         while (1) {
201                 for (len = 0;
202                      str[len] && str[len] != ':' && str[len] != ')'; len++);
203                 if (len == 2 && !strncmp(str, "ro", 2))
204                         features |= DASD_FEATURE_READONLY;
205                 else if (len == 4 && !strncmp(str, "diag", 4))
206                         features |= DASD_FEATURE_USEDIAG;
207                 else if (len == 6 && !strncmp(str, "erplog", 6))
208                         features |= DASD_FEATURE_ERPLOG;
209                 else {
210                         MESSAGE(KERN_WARNING,
211                                 "unsupported feature: %*s, "
212                                 "ignoring setting", len, str);
213                         rc = -EINVAL;
214                 }
215                 str += len;
216                 if (*str != ':')
217                         break;
218                 str++;
219         }
220         if (*str != ')') {
221                 MESSAGE(KERN_WARNING, "%s",
222                         "missing ')' in dasd parameter string\n");
223                 rc = -EINVAL;
224         } else
225                 str++;
226         *endp = str;
227         if (rc != 0)
228                 return rc;
229         return features;
230 }
231
232 /*
233  * Try to match the first element on the comma separated parse string
234  * with one of the known keywords. If a keyword is found, take the approprate
235  * action and return a pointer to the residual string. If the first element
236  * could not be matched to any keyword then return an error code.
237  */
238 static char *
239 dasd_parse_keyword( char *parsestring ) {
240
241         char *nextcomma, *residual_str;
242         int length;
243
244         nextcomma = strchr(parsestring,',');
245         if (nextcomma) {
246                 length = nextcomma - parsestring;
247                 residual_str = nextcomma + 1;
248         } else {
249                 length = strlen(parsestring);
250                 residual_str = parsestring + length;
251         }
252         if (strncmp("autodetect", parsestring, length) == 0) {
253                 dasd_autodetect = 1;
254                 MESSAGE (KERN_INFO, "%s",
255                          "turning to autodetection mode");
256                 return residual_str;
257         }
258         if (strncmp("probeonly", parsestring, length) == 0) {
259                 dasd_probeonly = 1;
260                 MESSAGE(KERN_INFO, "%s",
261                         "turning to probeonly mode");
262                 return residual_str;
263         }
264         if (strncmp("nopav", parsestring, length) == 0) {
265                 if (MACHINE_IS_VM)
266                         MESSAGE(KERN_INFO, "%s", "'nopav' not supported on VM");
267                 else {
268                         dasd_nopav = 1;
269                         MESSAGE(KERN_INFO, "%s", "disable PAV mode");
270                 }
271                 return residual_str;
272         }
273         if (strncmp("fixedbuffers", parsestring, length) == 0) {
274                 if (dasd_page_cache)
275                         return residual_str;
276                 dasd_page_cache =
277                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
278                                           PAGE_SIZE, SLAB_CACHE_DMA,
279                                           NULL);
280                 if (!dasd_page_cache)
281                         MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
282                                 "fixed buffer mode disabled.");
283                 else
284                         MESSAGE (KERN_INFO, "%s",
285                                  "turning on fixed buffer mode");
286                 return residual_str;
287         }
288         return ERR_PTR(-EINVAL);
289 }
290
291 /*
292  * Try to interprete the first element on the comma separated parse string
293  * as a device number or a range of devices. If the interpretation is
294  * successfull, create the matching dasd_devmap entries and return a pointer
295  * to the residual string.
296  * If interpretation fails or in case of an error, return an error code.
297  */
298 static char *
299 dasd_parse_range( char *parsestring ) {
300
301         struct dasd_devmap *devmap;
302         int from, from_id0, from_id1;
303         int to, to_id0, to_id1;
304         int features, rc;
305         char bus_id[DASD_BUS_ID_SIZE+1], *str;
306
307         str = parsestring;
308         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
309         if (rc == 0) {
310                 to = from;
311                 to_id0 = from_id0;
312                 to_id1 = from_id1;
313                 if (*str == '-') {
314                         str++;
315                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
316                 }
317         }
318         if (rc == 0 &&
319             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
320                 rc = -EINVAL;
321         if (rc) {
322                 MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
323                 return ERR_PTR(rc);
324         }
325         features = dasd_feature_list(str, &str);
326         if (features < 0)
327                 return ERR_PTR(-EINVAL);
328         /* each device in dasd= parameter should be set initially online */
329         features |= DASD_FEATURE_INITIAL_ONLINE;
330         while (from <= to) {
331                 sprintf(bus_id, "%01x.%01x.%04x",
332                         from_id0, from_id1, from++);
333                 devmap = dasd_add_busid(bus_id, features);
334                 if (IS_ERR(devmap))
335                         return (char *)devmap;
336         }
337         if (*str == ',')
338                 return str + 1;
339         if (*str == '\0')
340                 return str;
341         MESSAGE(KERN_WARNING,
342                 "junk at end of dasd parameter string: %s\n", str);
343         return ERR_PTR(-EINVAL);
344 }
345
346 static char *
347 dasd_parse_next_element( char *parsestring ) {
348         char * residual_str;
349         residual_str = dasd_parse_keyword(parsestring);
350         if (!IS_ERR(residual_str))
351                 return residual_str;
352         residual_str = dasd_parse_range(parsestring);
353         return residual_str;
354 }
355
356 /*
357  * Parse parameters stored in dasd[]
358  * The 'dasd=...' parameter allows to specify a comma separated list of
359  * keywords and device ranges. When the dasd driver is build into the kernel,
360  * the complete list will be stored as one element of the dasd[] array.
361  * When the dasd driver is build as a module, then the list is broken into
362  * it's elements and each dasd[] entry contains one element.
363  */
364 int
365 dasd_parse(void)
366 {
367         int rc, i;
368         char *parsestring;
369
370         rc = 0;
371         for (i = 0; i < 256; i++) {
372                 if (dasd[i] == NULL)
373                         break;
374                 parsestring = dasd[i];
375                 /* loop over the comma separated list in the parsestring */
376                 while (*parsestring) {
377                         parsestring = dasd_parse_next_element(parsestring);
378                         if(IS_ERR(parsestring)) {
379                                 rc = PTR_ERR(parsestring);
380                                 break;
381                         }
382                 }
383                 if (rc) {
384                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
385                         break;
386                 }
387         }
388         return rc;
389 }
390
391 /*
392  * Add a devmap for the device specified by busid. It is possible that
393  * the devmap already exists (dasd= parameter). The order of the devices
394  * added through this function will define the kdevs for the individual
395  * devices.
396  */
397 static struct dasd_devmap *
398 dasd_add_busid(const char *bus_id, int features)
399 {
400         struct dasd_devmap *devmap, *new, *tmp;
401         int hash;
402
403         new = (struct dasd_devmap *)
404                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
405         if (!new)
406                 return ERR_PTR(-ENOMEM);
407         spin_lock(&dasd_devmap_lock);
408         devmap = NULL;
409         hash = dasd_hash_busid(bus_id);
410         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
411                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
412                         devmap = tmp;
413                         break;
414                 }
415         if (!devmap) {
416                 /* This bus_id is new. */
417                 new->devindex = dasd_max_devindex++;
418                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
419                 new->features = features;
420                 new->device = NULL;
421                 list_add(&new->list, &dasd_hashlists[hash]);
422                 devmap = new;
423                 new = NULL;
424         }
425         spin_unlock(&dasd_devmap_lock);
426         kfree(new);
427         return devmap;
428 }
429
430 /*
431  * Find devmap for device with given bus_id.
432  */
433 static struct dasd_devmap *
434 dasd_find_busid(const char *bus_id)
435 {
436         struct dasd_devmap *devmap, *tmp;
437         int hash;
438
439         spin_lock(&dasd_devmap_lock);
440         devmap = ERR_PTR(-ENODEV);
441         hash = dasd_hash_busid(bus_id);
442         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
443                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
444                         devmap = tmp;
445                         break;
446                 }
447         }
448         spin_unlock(&dasd_devmap_lock);
449         return devmap;
450 }
451
452 /*
453  * Check if busid has been added to the list of dasd ranges.
454  */
455 int
456 dasd_busid_known(const char *bus_id)
457 {
458         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
459 }
460
461 /*
462  * Forget all about the device numbers added so far.
463  * This may only be called at module unload or system shutdown.
464  */
465 static void
466 dasd_forget_ranges(void)
467 {
468         struct dasd_devmap *devmap, *n;
469         int i;
470
471         spin_lock(&dasd_devmap_lock);
472         for (i = 0; i < 256; i++) {
473                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
474                         BUG_ON(devmap->device != NULL);
475                         list_del(&devmap->list);
476                         kfree(devmap);
477                 }
478         }
479         spin_unlock(&dasd_devmap_lock);
480 }
481
482 /*
483  * Find the device struct by its device index.
484  */
485 struct dasd_device *
486 dasd_device_from_devindex(int devindex)
487 {
488         struct dasd_devmap *devmap, *tmp;
489         struct dasd_device *device;
490         int i;
491
492         spin_lock(&dasd_devmap_lock);
493         devmap = NULL;
494         for (i = 0; (i < 256) && !devmap; i++)
495                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
496                         if (tmp->devindex == devindex) {
497                                 /* Found the devmap for the device. */
498                                 devmap = tmp;
499                                 break;
500                         }
501         if (devmap && devmap->device) {
502                 device = devmap->device;
503                 dasd_get_device(device);
504         } else
505                 device = ERR_PTR(-ENODEV);
506         spin_unlock(&dasd_devmap_lock);
507         return device;
508 }
509
510 /*
511  * Return devmap for cdev. If no devmap exists yet, create one and
512  * connect it to the cdev.
513  */
514 static struct dasd_devmap *
515 dasd_devmap_from_cdev(struct ccw_device *cdev)
516 {
517         struct dasd_devmap *devmap;
518
519         devmap = dasd_find_busid(dev_name(&cdev->dev));
520         if (IS_ERR(devmap))
521                 devmap = dasd_add_busid(dev_name(&cdev->dev),
522                                         DASD_FEATURE_DEFAULT);
523         return devmap;
524 }
525
526 /*
527  * Create a dasd device structure for cdev.
528  */
529 struct dasd_device *
530 dasd_create_device(struct ccw_device *cdev)
531 {
532         struct dasd_devmap *devmap;
533         struct dasd_device *device;
534         unsigned long flags;
535         int rc;
536
537         devmap = dasd_devmap_from_cdev(cdev);
538         if (IS_ERR(devmap))
539                 return (void *) devmap;
540
541         device = dasd_alloc_device();
542         if (IS_ERR(device))
543                 return device;
544         atomic_set(&device->ref_count, 3);
545
546         spin_lock(&dasd_devmap_lock);
547         if (!devmap->device) {
548                 devmap->device = device;
549                 device->devindex = devmap->devindex;
550                 device->features = devmap->features;
551                 get_device(&cdev->dev);
552                 device->cdev = cdev;
553                 rc = 0;
554         } else
555                 /* Someone else was faster. */
556                 rc = -EBUSY;
557         spin_unlock(&dasd_devmap_lock);
558
559         if (rc) {
560                 dasd_free_device(device);
561                 return ERR_PTR(rc);
562         }
563
564         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
565         dev_set_drvdata(&cdev->dev, device);
566         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
567
568         return device;
569 }
570
571 /*
572  * Wait queue for dasd_delete_device waits.
573  */
574 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
575
576 /*
577  * Remove a dasd device structure. The passed referenced
578  * is destroyed.
579  */
580 void
581 dasd_delete_device(struct dasd_device *device)
582 {
583         struct ccw_device *cdev;
584         struct dasd_devmap *devmap;
585         unsigned long flags;
586
587         /* First remove device pointer from devmap. */
588         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
589         BUG_ON(IS_ERR(devmap));
590         spin_lock(&dasd_devmap_lock);
591         if (devmap->device != device) {
592                 spin_unlock(&dasd_devmap_lock);
593                 dasd_put_device(device);
594                 return;
595         }
596         devmap->device = NULL;
597         spin_unlock(&dasd_devmap_lock);
598
599         /* Disconnect dasd_device structure from ccw_device structure. */
600         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
601         dev_set_drvdata(&device->cdev->dev, NULL);
602         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
603
604         /*
605          * Drop ref_count by 3, one for the devmap reference, one for
606          * the cdev reference and one for the passed reference.
607          */
608         atomic_sub(3, &device->ref_count);
609
610         /* Wait for reference counter to drop to zero. */
611         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
612
613         /* Disconnect dasd_device structure from ccw_device structure. */
614         cdev = device->cdev;
615         device->cdev = NULL;
616
617         /* Put ccw_device structure. */
618         put_device(&cdev->dev);
619
620         /* Now the device structure can be freed. */
621         dasd_free_device(device);
622 }
623
624 /*
625  * Reference counter dropped to zero. Wake up waiter
626  * in dasd_delete_device.
627  */
628 void
629 dasd_put_device_wake(struct dasd_device *device)
630 {
631         wake_up(&dasd_delete_wq);
632 }
633
634 /*
635  * Return dasd_device structure associated with cdev.
636  * This function needs to be called with the ccw device
637  * lock held. It can be used from interrupt context.
638  */
639 struct dasd_device *
640 dasd_device_from_cdev_locked(struct ccw_device *cdev)
641 {
642         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
643
644         if (!device)
645                 return ERR_PTR(-ENODEV);
646         dasd_get_device(device);
647         return device;
648 }
649
650 /*
651  * Return dasd_device structure associated with cdev.
652  */
653 struct dasd_device *
654 dasd_device_from_cdev(struct ccw_device *cdev)
655 {
656         struct dasd_device *device;
657         unsigned long flags;
658
659         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
660         device = dasd_device_from_cdev_locked(cdev);
661         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
662         return device;
663 }
664
665 /*
666  * SECTION: files in sysfs
667  */
668
669 /*
670  * readonly controls the readonly status of a dasd
671  */
672 static ssize_t
673 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
674 {
675         struct dasd_devmap *devmap;
676         int ro_flag;
677
678         devmap = dasd_find_busid(dev_name(dev));
679         if (!IS_ERR(devmap))
680                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
681         else
682                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
683         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
684 }
685
686 static ssize_t
687 dasd_ro_store(struct device *dev, struct device_attribute *attr,
688               const char *buf, size_t count)
689 {
690         struct dasd_devmap *devmap;
691         int val;
692         char *endp;
693
694         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
695         if (IS_ERR(devmap))
696                 return PTR_ERR(devmap);
697
698         val = simple_strtoul(buf, &endp, 0);
699         if (((endp + 1) < (buf + count)) || (val > 1))
700                 return -EINVAL;
701
702         spin_lock(&dasd_devmap_lock);
703         if (val)
704                 devmap->features |= DASD_FEATURE_READONLY;
705         else
706                 devmap->features &= ~DASD_FEATURE_READONLY;
707         if (devmap->device)
708                 devmap->device->features = devmap->features;
709         if (devmap->device && devmap->device->block
710             && devmap->device->block->gdp)
711                 set_disk_ro(devmap->device->block->gdp, val);
712         spin_unlock(&dasd_devmap_lock);
713         return count;
714 }
715
716 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
717 /*
718  * erplog controls the logging of ERP related data
719  * (e.g. failing channel programs).
720  */
721 static ssize_t
722 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
723 {
724         struct dasd_devmap *devmap;
725         int erplog;
726
727         devmap = dasd_find_busid(dev_name(dev));
728         if (!IS_ERR(devmap))
729                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
730         else
731                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
732         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
733 }
734
735 static ssize_t
736 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
737               const char *buf, size_t count)
738 {
739         struct dasd_devmap *devmap;
740         int val;
741         char *endp;
742
743         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
744         if (IS_ERR(devmap))
745                 return PTR_ERR(devmap);
746
747         val = simple_strtoul(buf, &endp, 0);
748         if (((endp + 1) < (buf + count)) || (val > 1))
749                 return -EINVAL;
750
751         spin_lock(&dasd_devmap_lock);
752         if (val)
753                 devmap->features |= DASD_FEATURE_ERPLOG;
754         else
755                 devmap->features &= ~DASD_FEATURE_ERPLOG;
756         if (devmap->device)
757                 devmap->device->features = devmap->features;
758         spin_unlock(&dasd_devmap_lock);
759         return count;
760 }
761
762 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
763
764 /*
765  * use_diag controls whether the driver should use diag rather than ssch
766  * to talk to the device
767  */
768 static ssize_t
769 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
770 {
771         struct dasd_devmap *devmap;
772         int use_diag;
773
774         devmap = dasd_find_busid(dev_name(dev));
775         if (!IS_ERR(devmap))
776                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
777         else
778                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
779         return sprintf(buf, use_diag ? "1\n" : "0\n");
780 }
781
782 static ssize_t
783 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
784                     const char *buf, size_t count)
785 {
786         struct dasd_devmap *devmap;
787         ssize_t rc;
788         int val;
789         char *endp;
790
791         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
792         if (IS_ERR(devmap))
793                 return PTR_ERR(devmap);
794
795         val = simple_strtoul(buf, &endp, 0);
796         if (((endp + 1) < (buf + count)) || (val > 1))
797                 return -EINVAL;
798
799         spin_lock(&dasd_devmap_lock);
800         /* Changing diag discipline flag is only allowed in offline state. */
801         rc = count;
802         if (!devmap->device) {
803                 if (val)
804                         devmap->features |= DASD_FEATURE_USEDIAG;
805                 else
806                         devmap->features &= ~DASD_FEATURE_USEDIAG;
807         } else
808                 rc = -EPERM;
809         spin_unlock(&dasd_devmap_lock);
810         return rc;
811 }
812
813 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
814
815 static ssize_t
816 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
817                      char *buf)
818 {
819         struct dasd_device *device;
820         ssize_t len;
821
822         device = dasd_device_from_cdev(to_ccwdev(dev));
823         if (!IS_ERR(device) && device->discipline) {
824                 len = snprintf(buf, PAGE_SIZE, "%s\n",
825                                device->discipline->name);
826                 dasd_put_device(device);
827         } else
828                 len = snprintf(buf, PAGE_SIZE, "none\n");
829         return len;
830 }
831
832 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
833
834 static ssize_t
835 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
836                      char *buf)
837 {
838         struct dasd_device *device;
839         ssize_t len;
840
841         device = dasd_device_from_cdev(to_ccwdev(dev));
842         if (!IS_ERR(device)) {
843                 switch (device->state) {
844                 case DASD_STATE_NEW:
845                         len = snprintf(buf, PAGE_SIZE, "new\n");
846                         break;
847                 case DASD_STATE_KNOWN:
848                         len = snprintf(buf, PAGE_SIZE, "detected\n");
849                         break;
850                 case DASD_STATE_BASIC:
851                         len = snprintf(buf, PAGE_SIZE, "basic\n");
852                         break;
853                 case DASD_STATE_UNFMT:
854                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
855                         break;
856                 case DASD_STATE_READY:
857                         len = snprintf(buf, PAGE_SIZE, "ready\n");
858                         break;
859                 case DASD_STATE_ONLINE:
860                         len = snprintf(buf, PAGE_SIZE, "online\n");
861                         break;
862                 default:
863                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
864                         break;
865                 }
866                 dasd_put_device(device);
867         } else
868                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
869         return len;
870 }
871
872 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
873
874 static ssize_t
875 dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
876 {
877         struct dasd_devmap *devmap;
878         int alias;
879
880         devmap = dasd_find_busid(dev_name(dev));
881         spin_lock(&dasd_devmap_lock);
882         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
883                 spin_unlock(&dasd_devmap_lock);
884                 return sprintf(buf, "0\n");
885         }
886         if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
887             devmap->uid.type == UA_HYPER_PAV_ALIAS)
888                 alias = 1;
889         else
890                 alias = 0;
891         spin_unlock(&dasd_devmap_lock);
892         return sprintf(buf, alias ? "1\n" : "0\n");
893 }
894
895 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
896
897 static ssize_t
898 dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
899 {
900         struct dasd_devmap *devmap;
901         char *vendor;
902
903         devmap = dasd_find_busid(dev_name(dev));
904         spin_lock(&dasd_devmap_lock);
905         if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
906                 vendor = devmap->uid.vendor;
907         else
908                 vendor = "";
909         spin_unlock(&dasd_devmap_lock);
910
911         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
912 }
913
914 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
915
916 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
917                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
918                      /* vduit */ 32 + 1)
919
920 static ssize_t
921 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
922 {
923         struct dasd_devmap *devmap;
924         char uid_string[UID_STRLEN];
925         char ua_string[3];
926         struct dasd_uid *uid;
927
928         devmap = dasd_find_busid(dev_name(dev));
929         spin_lock(&dasd_devmap_lock);
930         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
931                 spin_unlock(&dasd_devmap_lock);
932                 return sprintf(buf, "\n");
933         }
934         uid = &devmap->uid;
935         switch (uid->type) {
936         case UA_BASE_DEVICE:
937                 sprintf(ua_string, "%02x", uid->real_unit_addr);
938                 break;
939         case UA_BASE_PAV_ALIAS:
940                 sprintf(ua_string, "%02x", uid->base_unit_addr);
941                 break;
942         case UA_HYPER_PAV_ALIAS:
943                 sprintf(ua_string, "xx");
944                 break;
945         default:
946                 /* should not happen, treat like base device */
947                 sprintf(ua_string, "%02x", uid->real_unit_addr);
948                 break;
949         }
950         if (strlen(uid->vduit) > 0)
951                 snprintf(uid_string, sizeof(uid_string),
952                          "%s.%s.%04x.%s.%s",
953                          uid->vendor, uid->serial,
954                          uid->ssid, ua_string,
955                          uid->vduit);
956         else
957                 snprintf(uid_string, sizeof(uid_string),
958                          "%s.%s.%04x.%s",
959                          uid->vendor, uid->serial,
960                          uid->ssid, ua_string);
961         spin_unlock(&dasd_devmap_lock);
962         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
963 }
964
965 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
966
967 /*
968  * extended error-reporting
969  */
970 static ssize_t
971 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
972 {
973         struct dasd_devmap *devmap;
974         int eer_flag;
975
976         devmap = dasd_find_busid(dev_name(dev));
977         if (!IS_ERR(devmap) && devmap->device)
978                 eer_flag = dasd_eer_enabled(devmap->device);
979         else
980                 eer_flag = 0;
981         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
982 }
983
984 static ssize_t
985 dasd_eer_store(struct device *dev, struct device_attribute *attr,
986                const char *buf, size_t count)
987 {
988         struct dasd_devmap *devmap;
989         int val, rc;
990         char *endp;
991
992         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
993         if (IS_ERR(devmap))
994                 return PTR_ERR(devmap);
995         if (!devmap->device)
996                 return -ENODEV;
997
998         val = simple_strtoul(buf, &endp, 0);
999         if (((endp + 1) < (buf + count)) || (val > 1))
1000                 return -EINVAL;
1001
1002         if (val) {
1003                 rc = dasd_eer_enable(devmap->device);
1004                 if (rc)
1005                         return rc;
1006         } else
1007                 dasd_eer_disable(devmap->device);
1008         return count;
1009 }
1010
1011 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1012
1013 static struct attribute * dasd_attrs[] = {
1014         &dev_attr_readonly.attr,
1015         &dev_attr_discipline.attr,
1016         &dev_attr_status.attr,
1017         &dev_attr_alias.attr,
1018         &dev_attr_vendor.attr,
1019         &dev_attr_uid.attr,
1020         &dev_attr_use_diag.attr,
1021         &dev_attr_eer_enabled.attr,
1022         &dev_attr_erplog.attr,
1023         NULL,
1024 };
1025
1026 static struct attribute_group dasd_attr_group = {
1027         .attrs = dasd_attrs,
1028 };
1029
1030 /*
1031  * Return copy of the device unique identifier.
1032  */
1033 int
1034 dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1035 {
1036         struct dasd_devmap *devmap;
1037
1038         devmap = dasd_find_busid(dev_name(&cdev->dev));
1039         if (IS_ERR(devmap))
1040                 return PTR_ERR(devmap);
1041         spin_lock(&dasd_devmap_lock);
1042         *uid = devmap->uid;
1043         spin_unlock(&dasd_devmap_lock);
1044         return 0;
1045 }
1046
1047 /*
1048  * Register the given device unique identifier into devmap struct.
1049  * In addition check if the related storage server subsystem ID is already
1050  * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
1051  * create new entry.
1052  * Return 0 if server was already in serverlist,
1053  *        1 if the server was added successful
1054  *       <0 in case of error.
1055  */
1056 int
1057 dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1058 {
1059         struct dasd_devmap *devmap;
1060
1061         devmap = dasd_find_busid(dev_name(&cdev->dev));
1062         if (IS_ERR(devmap))
1063                 return PTR_ERR(devmap);
1064
1065         spin_lock(&dasd_devmap_lock);
1066         devmap->uid = *uid;
1067         spin_unlock(&dasd_devmap_lock);
1068
1069         return 0;
1070 }
1071 EXPORT_SYMBOL_GPL(dasd_set_uid);
1072
1073 /*
1074  * Return value of the specified feature.
1075  */
1076 int
1077 dasd_get_feature(struct ccw_device *cdev, int feature)
1078 {
1079         struct dasd_devmap *devmap;
1080
1081         devmap = dasd_find_busid(dev_name(&cdev->dev));
1082         if (IS_ERR(devmap))
1083                 return PTR_ERR(devmap);
1084
1085         return ((devmap->features & feature) != 0);
1086 }
1087
1088 /*
1089  * Set / reset given feature.
1090  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1091  */
1092 int
1093 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1094 {
1095         struct dasd_devmap *devmap;
1096
1097         devmap = dasd_find_busid(dev_name(&cdev->dev));
1098         if (IS_ERR(devmap))
1099                 return PTR_ERR(devmap);
1100
1101         spin_lock(&dasd_devmap_lock);
1102         if (flag)
1103                 devmap->features |= feature;
1104         else
1105                 devmap->features &= ~feature;
1106         if (devmap->device)
1107                 devmap->device->features = devmap->features;
1108         spin_unlock(&dasd_devmap_lock);
1109         return 0;
1110 }
1111
1112
1113 int
1114 dasd_add_sysfs_files(struct ccw_device *cdev)
1115 {
1116         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1117 }
1118
1119 void
1120 dasd_remove_sysfs_files(struct ccw_device *cdev)
1121 {
1122         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1123 }
1124
1125
1126 int
1127 dasd_devmap_init(void)
1128 {
1129         int i;
1130
1131         /* Initialize devmap structures. */
1132         dasd_max_devindex = 0;
1133         for (i = 0; i < 256; i++)
1134                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1135         return 0;
1136 }
1137
1138 void
1139 dasd_devmap_exit(void)
1140 {
1141         dasd_forget_ranges();
1142 }