Merge branch 'devel' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa...
[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 if (len == 8 && !strncmp(str, "failfast", 8))
210                         features |= DASD_FEATURE_FAILFAST;
211                 else {
212                         MESSAGE(KERN_WARNING,
213                                 "unsupported feature: %*s, "
214                                 "ignoring setting", len, str);
215                         rc = -EINVAL;
216                 }
217                 str += len;
218                 if (*str != ':')
219                         break;
220                 str++;
221         }
222         if (*str != ')') {
223                 MESSAGE(KERN_WARNING, "%s",
224                         "missing ')' in dasd parameter string\n");
225                 rc = -EINVAL;
226         } else
227                 str++;
228         *endp = str;
229         if (rc != 0)
230                 return rc;
231         return features;
232 }
233
234 /*
235  * Try to match the first element on the comma separated parse string
236  * with one of the known keywords. If a keyword is found, take the approprate
237  * action and return a pointer to the residual string. If the first element
238  * could not be matched to any keyword then return an error code.
239  */
240 static char *
241 dasd_parse_keyword( char *parsestring ) {
242
243         char *nextcomma, *residual_str;
244         int length;
245
246         nextcomma = strchr(parsestring,',');
247         if (nextcomma) {
248                 length = nextcomma - parsestring;
249                 residual_str = nextcomma + 1;
250         } else {
251                 length = strlen(parsestring);
252                 residual_str = parsestring + length;
253         }
254         if (strncmp("autodetect", parsestring, length) == 0) {
255                 dasd_autodetect = 1;
256                 MESSAGE (KERN_INFO, "%s",
257                          "turning to autodetection mode");
258                 return residual_str;
259         }
260         if (strncmp("probeonly", parsestring, length) == 0) {
261                 dasd_probeonly = 1;
262                 MESSAGE(KERN_INFO, "%s",
263                         "turning to probeonly mode");
264                 return residual_str;
265         }
266         if (strncmp("nopav", parsestring, length) == 0) {
267                 if (MACHINE_IS_VM)
268                         MESSAGE(KERN_INFO, "%s", "'nopav' not supported on VM");
269                 else {
270                         dasd_nopav = 1;
271                         MESSAGE(KERN_INFO, "%s", "disable PAV mode");
272                 }
273                 return residual_str;
274         }
275         if (strncmp("fixedbuffers", parsestring, length) == 0) {
276                 if (dasd_page_cache)
277                         return residual_str;
278                 dasd_page_cache =
279                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
280                                           PAGE_SIZE, SLAB_CACHE_DMA,
281                                           NULL);
282                 if (!dasd_page_cache)
283                         MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
284                                 "fixed buffer mode disabled.");
285                 else
286                         MESSAGE (KERN_INFO, "%s",
287                                  "turning on fixed buffer mode");
288                 return residual_str;
289         }
290         return ERR_PTR(-EINVAL);
291 }
292
293 /*
294  * Try to interprete the first element on the comma separated parse string
295  * as a device number or a range of devices. If the interpretation is
296  * successfull, create the matching dasd_devmap entries and return a pointer
297  * to the residual string.
298  * If interpretation fails or in case of an error, return an error code.
299  */
300 static char *
301 dasd_parse_range( char *parsestring ) {
302
303         struct dasd_devmap *devmap;
304         int from, from_id0, from_id1;
305         int to, to_id0, to_id1;
306         int features, rc;
307         char bus_id[DASD_BUS_ID_SIZE+1], *str;
308
309         str = parsestring;
310         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
311         if (rc == 0) {
312                 to = from;
313                 to_id0 = from_id0;
314                 to_id1 = from_id1;
315                 if (*str == '-') {
316                         str++;
317                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
318                 }
319         }
320         if (rc == 0 &&
321             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
322                 rc = -EINVAL;
323         if (rc) {
324                 MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
325                 return ERR_PTR(rc);
326         }
327         features = dasd_feature_list(str, &str);
328         if (features < 0)
329                 return ERR_PTR(-EINVAL);
330         /* each device in dasd= parameter should be set initially online */
331         features |= DASD_FEATURE_INITIAL_ONLINE;
332         while (from <= to) {
333                 sprintf(bus_id, "%01x.%01x.%04x",
334                         from_id0, from_id1, from++);
335                 devmap = dasd_add_busid(bus_id, features);
336                 if (IS_ERR(devmap))
337                         return (char *)devmap;
338         }
339         if (*str == ',')
340                 return str + 1;
341         if (*str == '\0')
342                 return str;
343         MESSAGE(KERN_WARNING,
344                 "junk at end of dasd parameter string: %s\n", str);
345         return ERR_PTR(-EINVAL);
346 }
347
348 static char *
349 dasd_parse_next_element( char *parsestring ) {
350         char * residual_str;
351         residual_str = dasd_parse_keyword(parsestring);
352         if (!IS_ERR(residual_str))
353                 return residual_str;
354         residual_str = dasd_parse_range(parsestring);
355         return residual_str;
356 }
357
358 /*
359  * Parse parameters stored in dasd[]
360  * The 'dasd=...' parameter allows to specify a comma separated list of
361  * keywords and device ranges. When the dasd driver is build into the kernel,
362  * the complete list will be stored as one element of the dasd[] array.
363  * When the dasd driver is build as a module, then the list is broken into
364  * it's elements and each dasd[] entry contains one element.
365  */
366 int
367 dasd_parse(void)
368 {
369         int rc, i;
370         char *parsestring;
371
372         rc = 0;
373         for (i = 0; i < 256; i++) {
374                 if (dasd[i] == NULL)
375                         break;
376                 parsestring = dasd[i];
377                 /* loop over the comma separated list in the parsestring */
378                 while (*parsestring) {
379                         parsestring = dasd_parse_next_element(parsestring);
380                         if(IS_ERR(parsestring)) {
381                                 rc = PTR_ERR(parsestring);
382                                 break;
383                         }
384                 }
385                 if (rc) {
386                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
387                         break;
388                 }
389         }
390         return rc;
391 }
392
393 /*
394  * Add a devmap for the device specified by busid. It is possible that
395  * the devmap already exists (dasd= parameter). The order of the devices
396  * added through this function will define the kdevs for the individual
397  * devices.
398  */
399 static struct dasd_devmap *
400 dasd_add_busid(const char *bus_id, int features)
401 {
402         struct dasd_devmap *devmap, *new, *tmp;
403         int hash;
404
405         new = (struct dasd_devmap *)
406                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
407         if (!new)
408                 return ERR_PTR(-ENOMEM);
409         spin_lock(&dasd_devmap_lock);
410         devmap = NULL;
411         hash = dasd_hash_busid(bus_id);
412         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
413                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
414                         devmap = tmp;
415                         break;
416                 }
417         if (!devmap) {
418                 /* This bus_id is new. */
419                 new->devindex = dasd_max_devindex++;
420                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
421                 new->features = features;
422                 new->device = NULL;
423                 list_add(&new->list, &dasd_hashlists[hash]);
424                 devmap = new;
425                 new = NULL;
426         }
427         spin_unlock(&dasd_devmap_lock);
428         kfree(new);
429         return devmap;
430 }
431
432 /*
433  * Find devmap for device with given bus_id.
434  */
435 static struct dasd_devmap *
436 dasd_find_busid(const char *bus_id)
437 {
438         struct dasd_devmap *devmap, *tmp;
439         int hash;
440
441         spin_lock(&dasd_devmap_lock);
442         devmap = ERR_PTR(-ENODEV);
443         hash = dasd_hash_busid(bus_id);
444         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
445                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
446                         devmap = tmp;
447                         break;
448                 }
449         }
450         spin_unlock(&dasd_devmap_lock);
451         return devmap;
452 }
453
454 /*
455  * Check if busid has been added to the list of dasd ranges.
456  */
457 int
458 dasd_busid_known(const char *bus_id)
459 {
460         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
461 }
462
463 /*
464  * Forget all about the device numbers added so far.
465  * This may only be called at module unload or system shutdown.
466  */
467 static void
468 dasd_forget_ranges(void)
469 {
470         struct dasd_devmap *devmap, *n;
471         int i;
472
473         spin_lock(&dasd_devmap_lock);
474         for (i = 0; i < 256; i++) {
475                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
476                         BUG_ON(devmap->device != NULL);
477                         list_del(&devmap->list);
478                         kfree(devmap);
479                 }
480         }
481         spin_unlock(&dasd_devmap_lock);
482 }
483
484 /*
485  * Find the device struct by its device index.
486  */
487 struct dasd_device *
488 dasd_device_from_devindex(int devindex)
489 {
490         struct dasd_devmap *devmap, *tmp;
491         struct dasd_device *device;
492         int i;
493
494         spin_lock(&dasd_devmap_lock);
495         devmap = NULL;
496         for (i = 0; (i < 256) && !devmap; i++)
497                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
498                         if (tmp->devindex == devindex) {
499                                 /* Found the devmap for the device. */
500                                 devmap = tmp;
501                                 break;
502                         }
503         if (devmap && devmap->device) {
504                 device = devmap->device;
505                 dasd_get_device(device);
506         } else
507                 device = ERR_PTR(-ENODEV);
508         spin_unlock(&dasd_devmap_lock);
509         return device;
510 }
511
512 /*
513  * Return devmap for cdev. If no devmap exists yet, create one and
514  * connect it to the cdev.
515  */
516 static struct dasd_devmap *
517 dasd_devmap_from_cdev(struct ccw_device *cdev)
518 {
519         struct dasd_devmap *devmap;
520
521         devmap = dasd_find_busid(dev_name(&cdev->dev));
522         if (IS_ERR(devmap))
523                 devmap = dasd_add_busid(dev_name(&cdev->dev),
524                                         DASD_FEATURE_DEFAULT);
525         return devmap;
526 }
527
528 /*
529  * Create a dasd device structure for cdev.
530  */
531 struct dasd_device *
532 dasd_create_device(struct ccw_device *cdev)
533 {
534         struct dasd_devmap *devmap;
535         struct dasd_device *device;
536         unsigned long flags;
537         int rc;
538
539         devmap = dasd_devmap_from_cdev(cdev);
540         if (IS_ERR(devmap))
541                 return (void *) devmap;
542
543         device = dasd_alloc_device();
544         if (IS_ERR(device))
545                 return device;
546         atomic_set(&device->ref_count, 3);
547
548         spin_lock(&dasd_devmap_lock);
549         if (!devmap->device) {
550                 devmap->device = device;
551                 device->devindex = devmap->devindex;
552                 device->features = devmap->features;
553                 get_device(&cdev->dev);
554                 device->cdev = cdev;
555                 rc = 0;
556         } else
557                 /* Someone else was faster. */
558                 rc = -EBUSY;
559         spin_unlock(&dasd_devmap_lock);
560
561         if (rc) {
562                 dasd_free_device(device);
563                 return ERR_PTR(rc);
564         }
565
566         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
567         dev_set_drvdata(&cdev->dev, device);
568         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
569
570         return device;
571 }
572
573 /*
574  * Wait queue for dasd_delete_device waits.
575  */
576 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
577
578 /*
579  * Remove a dasd device structure. The passed referenced
580  * is destroyed.
581  */
582 void
583 dasd_delete_device(struct dasd_device *device)
584 {
585         struct ccw_device *cdev;
586         struct dasd_devmap *devmap;
587         unsigned long flags;
588
589         /* First remove device pointer from devmap. */
590         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
591         BUG_ON(IS_ERR(devmap));
592         spin_lock(&dasd_devmap_lock);
593         if (devmap->device != device) {
594                 spin_unlock(&dasd_devmap_lock);
595                 dasd_put_device(device);
596                 return;
597         }
598         devmap->device = NULL;
599         spin_unlock(&dasd_devmap_lock);
600
601         /* Disconnect dasd_device structure from ccw_device structure. */
602         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
603         dev_set_drvdata(&device->cdev->dev, NULL);
604         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
605
606         /*
607          * Drop ref_count by 3, one for the devmap reference, one for
608          * the cdev reference and one for the passed reference.
609          */
610         atomic_sub(3, &device->ref_count);
611
612         /* Wait for reference counter to drop to zero. */
613         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
614
615         /* Disconnect dasd_device structure from ccw_device structure. */
616         cdev = device->cdev;
617         device->cdev = NULL;
618
619         /* Put ccw_device structure. */
620         put_device(&cdev->dev);
621
622         /* Now the device structure can be freed. */
623         dasd_free_device(device);
624 }
625
626 /*
627  * Reference counter dropped to zero. Wake up waiter
628  * in dasd_delete_device.
629  */
630 void
631 dasd_put_device_wake(struct dasd_device *device)
632 {
633         wake_up(&dasd_delete_wq);
634 }
635
636 /*
637  * Return dasd_device structure associated with cdev.
638  * This function needs to be called with the ccw device
639  * lock held. It can be used from interrupt context.
640  */
641 struct dasd_device *
642 dasd_device_from_cdev_locked(struct ccw_device *cdev)
643 {
644         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
645
646         if (!device)
647                 return ERR_PTR(-ENODEV);
648         dasd_get_device(device);
649         return device;
650 }
651
652 /*
653  * Return dasd_device structure associated with cdev.
654  */
655 struct dasd_device *
656 dasd_device_from_cdev(struct ccw_device *cdev)
657 {
658         struct dasd_device *device;
659         unsigned long flags;
660
661         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
662         device = dasd_device_from_cdev_locked(cdev);
663         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
664         return device;
665 }
666
667 /*
668  * SECTION: files in sysfs
669  */
670
671 /*
672  * failfast controls the behaviour, if no path is available
673  */
674 static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
675                             char *buf)
676 {
677         struct dasd_devmap *devmap;
678         int ff_flag;
679
680         devmap = dasd_find_busid(dev_name(dev));
681         if (!IS_ERR(devmap))
682                 ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
683         else
684                 ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
685         return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
686 }
687
688 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
689               const char *buf, size_t count)
690 {
691         struct dasd_devmap *devmap;
692         int val;
693         char *endp;
694
695         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
696         if (IS_ERR(devmap))
697                 return PTR_ERR(devmap);
698
699         val = simple_strtoul(buf, &endp, 0);
700         if (((endp + 1) < (buf + count)) || (val > 1))
701                 return -EINVAL;
702
703         spin_lock(&dasd_devmap_lock);
704         if (val)
705                 devmap->features |= DASD_FEATURE_FAILFAST;
706         else
707                 devmap->features &= ~DASD_FEATURE_FAILFAST;
708         if (devmap->device)
709                 devmap->device->features = devmap->features;
710         spin_unlock(&dasd_devmap_lock);
711         return count;
712 }
713
714 static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
715
716 /*
717  * readonly controls the readonly status of a dasd
718  */
719 static ssize_t
720 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
721 {
722         struct dasd_devmap *devmap;
723         int ro_flag;
724
725         devmap = dasd_find_busid(dev_name(dev));
726         if (!IS_ERR(devmap))
727                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
728         else
729                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
730         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
731 }
732
733 static ssize_t
734 dasd_ro_store(struct device *dev, struct device_attribute *attr,
735               const char *buf, size_t count)
736 {
737         struct dasd_devmap *devmap;
738         int val;
739         char *endp;
740
741         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
742         if (IS_ERR(devmap))
743                 return PTR_ERR(devmap);
744
745         val = simple_strtoul(buf, &endp, 0);
746         if (((endp + 1) < (buf + count)) || (val > 1))
747                 return -EINVAL;
748
749         spin_lock(&dasd_devmap_lock);
750         if (val)
751                 devmap->features |= DASD_FEATURE_READONLY;
752         else
753                 devmap->features &= ~DASD_FEATURE_READONLY;
754         if (devmap->device)
755                 devmap->device->features = devmap->features;
756         if (devmap->device && devmap->device->block
757             && devmap->device->block->gdp)
758                 set_disk_ro(devmap->device->block->gdp, val);
759         spin_unlock(&dasd_devmap_lock);
760         return count;
761 }
762
763 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
764 /*
765  * erplog controls the logging of ERP related data
766  * (e.g. failing channel programs).
767  */
768 static ssize_t
769 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
770 {
771         struct dasd_devmap *devmap;
772         int erplog;
773
774         devmap = dasd_find_busid(dev_name(dev));
775         if (!IS_ERR(devmap))
776                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
777         else
778                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
779         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
780 }
781
782 static ssize_t
783 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
784               const char *buf, size_t count)
785 {
786         struct dasd_devmap *devmap;
787         int val;
788         char *endp;
789
790         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
791         if (IS_ERR(devmap))
792                 return PTR_ERR(devmap);
793
794         val = simple_strtoul(buf, &endp, 0);
795         if (((endp + 1) < (buf + count)) || (val > 1))
796                 return -EINVAL;
797
798         spin_lock(&dasd_devmap_lock);
799         if (val)
800                 devmap->features |= DASD_FEATURE_ERPLOG;
801         else
802                 devmap->features &= ~DASD_FEATURE_ERPLOG;
803         if (devmap->device)
804                 devmap->device->features = devmap->features;
805         spin_unlock(&dasd_devmap_lock);
806         return count;
807 }
808
809 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
810
811 /*
812  * use_diag controls whether the driver should use diag rather than ssch
813  * to talk to the device
814  */
815 static ssize_t
816 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
817 {
818         struct dasd_devmap *devmap;
819         int use_diag;
820
821         devmap = dasd_find_busid(dev_name(dev));
822         if (!IS_ERR(devmap))
823                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
824         else
825                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
826         return sprintf(buf, use_diag ? "1\n" : "0\n");
827 }
828
829 static ssize_t
830 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
831                     const char *buf, size_t count)
832 {
833         struct dasd_devmap *devmap;
834         ssize_t rc;
835         int val;
836         char *endp;
837
838         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
839         if (IS_ERR(devmap))
840                 return PTR_ERR(devmap);
841
842         val = simple_strtoul(buf, &endp, 0);
843         if (((endp + 1) < (buf + count)) || (val > 1))
844                 return -EINVAL;
845
846         spin_lock(&dasd_devmap_lock);
847         /* Changing diag discipline flag is only allowed in offline state. */
848         rc = count;
849         if (!devmap->device) {
850                 if (val)
851                         devmap->features |= DASD_FEATURE_USEDIAG;
852                 else
853                         devmap->features &= ~DASD_FEATURE_USEDIAG;
854         } else
855                 rc = -EPERM;
856         spin_unlock(&dasd_devmap_lock);
857         return rc;
858 }
859
860 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
861
862 static ssize_t
863 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
864                      char *buf)
865 {
866         struct dasd_device *device;
867         ssize_t len;
868
869         device = dasd_device_from_cdev(to_ccwdev(dev));
870         if (!IS_ERR(device) && device->discipline) {
871                 len = snprintf(buf, PAGE_SIZE, "%s\n",
872                                device->discipline->name);
873                 dasd_put_device(device);
874         } else
875                 len = snprintf(buf, PAGE_SIZE, "none\n");
876         return len;
877 }
878
879 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
880
881 static ssize_t
882 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
883                      char *buf)
884 {
885         struct dasd_device *device;
886         ssize_t len;
887
888         device = dasd_device_from_cdev(to_ccwdev(dev));
889         if (!IS_ERR(device)) {
890                 switch (device->state) {
891                 case DASD_STATE_NEW:
892                         len = snprintf(buf, PAGE_SIZE, "new\n");
893                         break;
894                 case DASD_STATE_KNOWN:
895                         len = snprintf(buf, PAGE_SIZE, "detected\n");
896                         break;
897                 case DASD_STATE_BASIC:
898                         len = snprintf(buf, PAGE_SIZE, "basic\n");
899                         break;
900                 case DASD_STATE_UNFMT:
901                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
902                         break;
903                 case DASD_STATE_READY:
904                         len = snprintf(buf, PAGE_SIZE, "ready\n");
905                         break;
906                 case DASD_STATE_ONLINE:
907                         len = snprintf(buf, PAGE_SIZE, "online\n");
908                         break;
909                 default:
910                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
911                         break;
912                 }
913                 dasd_put_device(device);
914         } else
915                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
916         return len;
917 }
918
919 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
920
921 static ssize_t
922 dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
923 {
924         struct dasd_devmap *devmap;
925         int alias;
926
927         devmap = dasd_find_busid(dev_name(dev));
928         spin_lock(&dasd_devmap_lock);
929         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
930                 spin_unlock(&dasd_devmap_lock);
931                 return sprintf(buf, "0\n");
932         }
933         if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
934             devmap->uid.type == UA_HYPER_PAV_ALIAS)
935                 alias = 1;
936         else
937                 alias = 0;
938         spin_unlock(&dasd_devmap_lock);
939         return sprintf(buf, alias ? "1\n" : "0\n");
940 }
941
942 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
943
944 static ssize_t
945 dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
946 {
947         struct dasd_devmap *devmap;
948         char *vendor;
949
950         devmap = dasd_find_busid(dev_name(dev));
951         spin_lock(&dasd_devmap_lock);
952         if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
953                 vendor = devmap->uid.vendor;
954         else
955                 vendor = "";
956         spin_unlock(&dasd_devmap_lock);
957
958         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
959 }
960
961 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
962
963 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
964                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
965                      /* vduit */ 32 + 1)
966
967 static ssize_t
968 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
969 {
970         struct dasd_devmap *devmap;
971         char uid_string[UID_STRLEN];
972         char ua_string[3];
973         struct dasd_uid *uid;
974
975         devmap = dasd_find_busid(dev_name(dev));
976         spin_lock(&dasd_devmap_lock);
977         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
978                 spin_unlock(&dasd_devmap_lock);
979                 return sprintf(buf, "\n");
980         }
981         uid = &devmap->uid;
982         switch (uid->type) {
983         case UA_BASE_DEVICE:
984                 sprintf(ua_string, "%02x", uid->real_unit_addr);
985                 break;
986         case UA_BASE_PAV_ALIAS:
987                 sprintf(ua_string, "%02x", uid->base_unit_addr);
988                 break;
989         case UA_HYPER_PAV_ALIAS:
990                 sprintf(ua_string, "xx");
991                 break;
992         default:
993                 /* should not happen, treat like base device */
994                 sprintf(ua_string, "%02x", uid->real_unit_addr);
995                 break;
996         }
997         if (strlen(uid->vduit) > 0)
998                 snprintf(uid_string, sizeof(uid_string),
999                          "%s.%s.%04x.%s.%s",
1000                          uid->vendor, uid->serial,
1001                          uid->ssid, ua_string,
1002                          uid->vduit);
1003         else
1004                 snprintf(uid_string, sizeof(uid_string),
1005                          "%s.%s.%04x.%s",
1006                          uid->vendor, uid->serial,
1007                          uid->ssid, ua_string);
1008         spin_unlock(&dasd_devmap_lock);
1009         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1010 }
1011
1012 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
1013
1014 /*
1015  * extended error-reporting
1016  */
1017 static ssize_t
1018 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
1019 {
1020         struct dasd_devmap *devmap;
1021         int eer_flag;
1022
1023         devmap = dasd_find_busid(dev_name(dev));
1024         if (!IS_ERR(devmap) && devmap->device)
1025                 eer_flag = dasd_eer_enabled(devmap->device);
1026         else
1027                 eer_flag = 0;
1028         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
1029 }
1030
1031 static ssize_t
1032 dasd_eer_store(struct device *dev, struct device_attribute *attr,
1033                const char *buf, size_t count)
1034 {
1035         struct dasd_devmap *devmap;
1036         int val, rc;
1037         char *endp;
1038
1039         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1040         if (IS_ERR(devmap))
1041                 return PTR_ERR(devmap);
1042         if (!devmap->device)
1043                 return -ENODEV;
1044
1045         val = simple_strtoul(buf, &endp, 0);
1046         if (((endp + 1) < (buf + count)) || (val > 1))
1047                 return -EINVAL;
1048
1049         if (val) {
1050                 rc = dasd_eer_enable(devmap->device);
1051                 if (rc)
1052                         return rc;
1053         } else
1054                 dasd_eer_disable(devmap->device);
1055         return count;
1056 }
1057
1058 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1059
1060 static struct attribute * dasd_attrs[] = {
1061         &dev_attr_readonly.attr,
1062         &dev_attr_discipline.attr,
1063         &dev_attr_status.attr,
1064         &dev_attr_alias.attr,
1065         &dev_attr_vendor.attr,
1066         &dev_attr_uid.attr,
1067         &dev_attr_use_diag.attr,
1068         &dev_attr_eer_enabled.attr,
1069         &dev_attr_erplog.attr,
1070         &dev_attr_failfast.attr,
1071         NULL,
1072 };
1073
1074 static struct attribute_group dasd_attr_group = {
1075         .attrs = dasd_attrs,
1076 };
1077
1078 /*
1079  * Return copy of the device unique identifier.
1080  */
1081 int
1082 dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1083 {
1084         struct dasd_devmap *devmap;
1085
1086         devmap = dasd_find_busid(dev_name(&cdev->dev));
1087         if (IS_ERR(devmap))
1088                 return PTR_ERR(devmap);
1089         spin_lock(&dasd_devmap_lock);
1090         *uid = devmap->uid;
1091         spin_unlock(&dasd_devmap_lock);
1092         return 0;
1093 }
1094
1095 /*
1096  * Register the given device unique identifier into devmap struct.
1097  * In addition check if the related storage server subsystem ID is already
1098  * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
1099  * create new entry.
1100  * Return 0 if server was already in serverlist,
1101  *        1 if the server was added successful
1102  *       <0 in case of error.
1103  */
1104 int
1105 dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1106 {
1107         struct dasd_devmap *devmap;
1108
1109         devmap = dasd_find_busid(dev_name(&cdev->dev));
1110         if (IS_ERR(devmap))
1111                 return PTR_ERR(devmap);
1112
1113         spin_lock(&dasd_devmap_lock);
1114         devmap->uid = *uid;
1115         spin_unlock(&dasd_devmap_lock);
1116
1117         return 0;
1118 }
1119 EXPORT_SYMBOL_GPL(dasd_set_uid);
1120
1121 /*
1122  * Return value of the specified feature.
1123  */
1124 int
1125 dasd_get_feature(struct ccw_device *cdev, int feature)
1126 {
1127         struct dasd_devmap *devmap;
1128
1129         devmap = dasd_find_busid(dev_name(&cdev->dev));
1130         if (IS_ERR(devmap))
1131                 return PTR_ERR(devmap);
1132
1133         return ((devmap->features & feature) != 0);
1134 }
1135
1136 /*
1137  * Set / reset given feature.
1138  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1139  */
1140 int
1141 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1142 {
1143         struct dasd_devmap *devmap;
1144
1145         devmap = dasd_find_busid(dev_name(&cdev->dev));
1146         if (IS_ERR(devmap))
1147                 return PTR_ERR(devmap);
1148
1149         spin_lock(&dasd_devmap_lock);
1150         if (flag)
1151                 devmap->features |= feature;
1152         else
1153                 devmap->features &= ~feature;
1154         if (devmap->device)
1155                 devmap->device->features = devmap->features;
1156         spin_unlock(&dasd_devmap_lock);
1157         return 0;
1158 }
1159
1160
1161 int
1162 dasd_add_sysfs_files(struct ccw_device *cdev)
1163 {
1164         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1165 }
1166
1167 void
1168 dasd_remove_sysfs_files(struct ccw_device *cdev)
1169 {
1170         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1171 }
1172
1173
1174 int
1175 dasd_devmap_init(void)
1176 {
1177         int i;
1178
1179         /* Initialize devmap structures. */
1180         dasd_max_devindex = 0;
1181         for (i = 0; i < 256; i++)
1182                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1183         return 0;
1184 }
1185
1186 void
1187 dasd_devmap_exit(void)
1188 {
1189         dasd_forget_ranges();
1190 }