Merge branch 'linus' into core/softlockup
[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 #define KMSG_COMPONENT "dasd"
17
18 #include <linux/ctype.h>
19 #include <linux/init.h>
20 #include <linux/module.h>
21
22 #include <asm/debug.h>
23 #include <asm/uaccess.h>
24 #include <asm/ipl.h>
25
26 /* This is ugly... */
27 #define PRINTK_HEADER "dasd_devmap:"
28 #define DASD_BUS_ID_SIZE 20
29
30 #include "dasd_int.h"
31
32 struct kmem_cache *dasd_page_cache;
33 EXPORT_SYMBOL_GPL(dasd_page_cache);
34
35 /*
36  * dasd_devmap_t is used to store the features and the relation
37  * between device number and device index. To find a dasd_devmap_t
38  * that corresponds to a device number of a device index each
39  * dasd_devmap_t is added to two linked lists, one to search by
40  * the device number and one to search by the device index. As
41  * soon as big minor numbers are available the device index list
42  * can be removed since the device number will then be identical
43  * to the device index.
44  */
45 struct dasd_devmap {
46         struct list_head list;
47         char bus_id[DASD_BUS_ID_SIZE];
48         unsigned int devindex;
49         unsigned short features;
50         struct dasd_device *device;
51         struct dasd_uid uid;
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 == 6 && !strncmp(str, "erplog", 6))
212                         features |= DASD_FEATURE_ERPLOG;
213                 else if (len == 8 && !strncmp(str, "failfast", 8))
214                         features |= DASD_FEATURE_FAILFAST;
215                 else {
216                         pr_warning("%*s is not a supported device option\n",
217                                    len, str);
218                         rc = -EINVAL;
219                 }
220                 str += len;
221                 if (*str != ':')
222                         break;
223                 str++;
224         }
225         if (*str != ')') {
226                 pr_warning("A closing parenthesis ')' is missing in the "
227                            "dasd= parameter\n");
228                 rc = -EINVAL;
229         } else
230                 str++;
231         *endp = str;
232         if (rc != 0)
233                 return rc;
234         return features;
235 }
236
237 /*
238  * Try to match the first element on the comma separated parse string
239  * with one of the known keywords. If a keyword is found, take the approprate
240  * action and return a pointer to the residual string. If the first element
241  * could not be matched to any keyword then return an error code.
242  */
243 static char *
244 dasd_parse_keyword( char *parsestring ) {
245
246         char *nextcomma, *residual_str;
247         int length;
248
249         nextcomma = strchr(parsestring,',');
250         if (nextcomma) {
251                 length = nextcomma - parsestring;
252                 residual_str = nextcomma + 1;
253         } else {
254                 length = strlen(parsestring);
255                 residual_str = parsestring + length;
256         }
257         if (strncmp("autodetect", parsestring, length) == 0) {
258                 dasd_autodetect = 1;
259                 pr_info("The autodetection mode has been activated\n");
260                 return residual_str;
261         }
262         if (strncmp("probeonly", parsestring, length) == 0) {
263                 dasd_probeonly = 1;
264                 pr_info("The probeonly mode has been activated\n");
265                 return residual_str;
266         }
267         if (strncmp("nopav", parsestring, length) == 0) {
268                 if (MACHINE_IS_VM)
269                         pr_info("'nopav' is not supported on z/VM\n");
270                 else {
271                         dasd_nopav = 1;
272                         pr_info("PAV support has be deactivated\n");
273                 }
274                 return residual_str;
275         }
276         if (strncmp("nofcx", parsestring, length) == 0) {
277                 dasd_nofcx = 1;
278                 pr_info("High Performance FICON support has been "
279                         "deactivated\n");
280                 return residual_str;
281         }
282         if (strncmp("fixedbuffers", parsestring, length) == 0) {
283                 if (dasd_page_cache)
284                         return residual_str;
285                 dasd_page_cache =
286                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
287                                           PAGE_SIZE, SLAB_CACHE_DMA,
288                                           NULL);
289                 if (!dasd_page_cache)
290                         DBF_EVENT(DBF_WARNING, "%s", "Failed to create slab, "
291                                 "fixed buffer mode disabled.");
292                 else
293                         DBF_EVENT(DBF_INFO, "%s",
294                                  "turning on fixed buffer mode");
295                 return residual_str;
296         }
297         return ERR_PTR(-EINVAL);
298 }
299
300 /*
301  * Try to interprete the first element on the comma separated parse string
302  * as a device number or a range of devices. If the interpretation is
303  * successfull, create the matching dasd_devmap entries and return a pointer
304  * to the residual string.
305  * If interpretation fails or in case of an error, return an error code.
306  */
307 static char *
308 dasd_parse_range( char *parsestring ) {
309
310         struct dasd_devmap *devmap;
311         int from, from_id0, from_id1;
312         int to, to_id0, to_id1;
313         int features, rc;
314         char bus_id[DASD_BUS_ID_SIZE+1], *str;
315
316         str = parsestring;
317         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
318         if (rc == 0) {
319                 to = from;
320                 to_id0 = from_id0;
321                 to_id1 = from_id1;
322                 if (*str == '-') {
323                         str++;
324                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
325                 }
326         }
327         if (rc == 0 &&
328             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
329                 rc = -EINVAL;
330         if (rc) {
331                 pr_err("%s is not a valid device range\n", parsestring);
332                 return ERR_PTR(rc);
333         }
334         features = dasd_feature_list(str, &str);
335         if (features < 0)
336                 return ERR_PTR(-EINVAL);
337         /* each device in dasd= parameter should be set initially online */
338         features |= DASD_FEATURE_INITIAL_ONLINE;
339         while (from <= to) {
340                 sprintf(bus_id, "%01x.%01x.%04x",
341                         from_id0, from_id1, from++);
342                 devmap = dasd_add_busid(bus_id, features);
343                 if (IS_ERR(devmap))
344                         return (char *)devmap;
345         }
346         if (*str == ',')
347                 return str + 1;
348         if (*str == '\0')
349                 return str;
350         pr_warning("The dasd= parameter value %s has an invalid ending\n",
351                    str);
352         return ERR_PTR(-EINVAL);
353 }
354
355 static char *
356 dasd_parse_next_element( char *parsestring ) {
357         char * residual_str;
358         residual_str = dasd_parse_keyword(parsestring);
359         if (!IS_ERR(residual_str))
360                 return residual_str;
361         residual_str = dasd_parse_range(parsestring);
362         return residual_str;
363 }
364
365 /*
366  * Parse parameters stored in dasd[]
367  * The 'dasd=...' parameter allows to specify a comma separated list of
368  * keywords and device ranges. When the dasd driver is build into the kernel,
369  * the complete list will be stored as one element of the dasd[] array.
370  * When the dasd driver is build as a module, then the list is broken into
371  * it's elements and each dasd[] entry contains one element.
372  */
373 int
374 dasd_parse(void)
375 {
376         int rc, i;
377         char *parsestring;
378
379         rc = 0;
380         for (i = 0; i < 256; i++) {
381                 if (dasd[i] == NULL)
382                         break;
383                 parsestring = dasd[i];
384                 /* loop over the comma separated list in the parsestring */
385                 while (*parsestring) {
386                         parsestring = dasd_parse_next_element(parsestring);
387                         if(IS_ERR(parsestring)) {
388                                 rc = PTR_ERR(parsestring);
389                                 break;
390                         }
391                 }
392                 if (rc) {
393                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
394                         break;
395                 }
396         }
397         return rc;
398 }
399
400 /*
401  * Add a devmap for the device specified by busid. It is possible that
402  * the devmap already exists (dasd= parameter). The order of the devices
403  * added through this function will define the kdevs for the individual
404  * devices.
405  */
406 static struct dasd_devmap *
407 dasd_add_busid(const char *bus_id, int features)
408 {
409         struct dasd_devmap *devmap, *new, *tmp;
410         int hash;
411
412         new = (struct dasd_devmap *)
413                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
414         if (!new)
415                 return ERR_PTR(-ENOMEM);
416         spin_lock(&dasd_devmap_lock);
417         devmap = NULL;
418         hash = dasd_hash_busid(bus_id);
419         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
420                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
421                         devmap = tmp;
422                         break;
423                 }
424         if (!devmap) {
425                 /* This bus_id is new. */
426                 new->devindex = dasd_max_devindex++;
427                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
428                 new->features = features;
429                 new->device = NULL;
430                 list_add(&new->list, &dasd_hashlists[hash]);
431                 devmap = new;
432                 new = NULL;
433         }
434         spin_unlock(&dasd_devmap_lock);
435         kfree(new);
436         return devmap;
437 }
438
439 /*
440  * Find devmap for device with given bus_id.
441  */
442 static struct dasd_devmap *
443 dasd_find_busid(const char *bus_id)
444 {
445         struct dasd_devmap *devmap, *tmp;
446         int hash;
447
448         spin_lock(&dasd_devmap_lock);
449         devmap = ERR_PTR(-ENODEV);
450         hash = dasd_hash_busid(bus_id);
451         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
452                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
453                         devmap = tmp;
454                         break;
455                 }
456         }
457         spin_unlock(&dasd_devmap_lock);
458         return devmap;
459 }
460
461 /*
462  * Check if busid has been added to the list of dasd ranges.
463  */
464 int
465 dasd_busid_known(const char *bus_id)
466 {
467         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
468 }
469
470 /*
471  * Forget all about the device numbers added so far.
472  * This may only be called at module unload or system shutdown.
473  */
474 static void
475 dasd_forget_ranges(void)
476 {
477         struct dasd_devmap *devmap, *n;
478         int i;
479
480         spin_lock(&dasd_devmap_lock);
481         for (i = 0; i < 256; i++) {
482                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
483                         BUG_ON(devmap->device != NULL);
484                         list_del(&devmap->list);
485                         kfree(devmap);
486                 }
487         }
488         spin_unlock(&dasd_devmap_lock);
489 }
490
491 /*
492  * Find the device struct by its device index.
493  */
494 struct dasd_device *
495 dasd_device_from_devindex(int devindex)
496 {
497         struct dasd_devmap *devmap, *tmp;
498         struct dasd_device *device;
499         int i;
500
501         spin_lock(&dasd_devmap_lock);
502         devmap = NULL;
503         for (i = 0; (i < 256) && !devmap; i++)
504                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
505                         if (tmp->devindex == devindex) {
506                                 /* Found the devmap for the device. */
507                                 devmap = tmp;
508                                 break;
509                         }
510         if (devmap && devmap->device) {
511                 device = devmap->device;
512                 dasd_get_device(device);
513         } else
514                 device = ERR_PTR(-ENODEV);
515         spin_unlock(&dasd_devmap_lock);
516         return device;
517 }
518
519 /*
520  * Return devmap for cdev. If no devmap exists yet, create one and
521  * connect it to the cdev.
522  */
523 static struct dasd_devmap *
524 dasd_devmap_from_cdev(struct ccw_device *cdev)
525 {
526         struct dasd_devmap *devmap;
527
528         devmap = dasd_find_busid(dev_name(&cdev->dev));
529         if (IS_ERR(devmap))
530                 devmap = dasd_add_busid(dev_name(&cdev->dev),
531                                         DASD_FEATURE_DEFAULT);
532         return devmap;
533 }
534
535 /*
536  * Create a dasd device structure for cdev.
537  */
538 struct dasd_device *
539 dasd_create_device(struct ccw_device *cdev)
540 {
541         struct dasd_devmap *devmap;
542         struct dasd_device *device;
543         unsigned long flags;
544         int rc;
545
546         devmap = dasd_devmap_from_cdev(cdev);
547         if (IS_ERR(devmap))
548                 return (void *) devmap;
549
550         device = dasd_alloc_device();
551         if (IS_ERR(device))
552                 return device;
553         atomic_set(&device->ref_count, 3);
554
555         spin_lock(&dasd_devmap_lock);
556         if (!devmap->device) {
557                 devmap->device = device;
558                 device->devindex = devmap->devindex;
559                 device->features = devmap->features;
560                 get_device(&cdev->dev);
561                 device->cdev = cdev;
562                 rc = 0;
563         } else
564                 /* Someone else was faster. */
565                 rc = -EBUSY;
566         spin_unlock(&dasd_devmap_lock);
567
568         if (rc) {
569                 dasd_free_device(device);
570                 return ERR_PTR(rc);
571         }
572
573         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
574         dev_set_drvdata(&cdev->dev, device);
575         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
576
577         return device;
578 }
579
580 /*
581  * Wait queue for dasd_delete_device waits.
582  */
583 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
584
585 /*
586  * Remove a dasd device structure. The passed referenced
587  * is destroyed.
588  */
589 void
590 dasd_delete_device(struct dasd_device *device)
591 {
592         struct ccw_device *cdev;
593         struct dasd_devmap *devmap;
594         unsigned long flags;
595
596         /* First remove device pointer from devmap. */
597         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
598         BUG_ON(IS_ERR(devmap));
599         spin_lock(&dasd_devmap_lock);
600         if (devmap->device != device) {
601                 spin_unlock(&dasd_devmap_lock);
602                 dasd_put_device(device);
603                 return;
604         }
605         devmap->device = NULL;
606         spin_unlock(&dasd_devmap_lock);
607
608         /* Disconnect dasd_device structure from ccw_device structure. */
609         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
610         dev_set_drvdata(&device->cdev->dev, NULL);
611         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
612
613         /*
614          * Drop ref_count by 3, one for the devmap reference, one for
615          * the cdev reference and one for the passed reference.
616          */
617         atomic_sub(3, &device->ref_count);
618
619         /* Wait for reference counter to drop to zero. */
620         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
621
622         /* Disconnect dasd_device structure from ccw_device structure. */
623         cdev = device->cdev;
624         device->cdev = NULL;
625
626         /* Put ccw_device structure. */
627         put_device(&cdev->dev);
628
629         /* Now the device structure can be freed. */
630         dasd_free_device(device);
631 }
632
633 /*
634  * Reference counter dropped to zero. Wake up waiter
635  * in dasd_delete_device.
636  */
637 void
638 dasd_put_device_wake(struct dasd_device *device)
639 {
640         wake_up(&dasd_delete_wq);
641 }
642
643 /*
644  * Return dasd_device structure associated with cdev.
645  * This function needs to be called with the ccw device
646  * lock held. It can be used from interrupt context.
647  */
648 struct dasd_device *
649 dasd_device_from_cdev_locked(struct ccw_device *cdev)
650 {
651         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
652
653         if (!device)
654                 return ERR_PTR(-ENODEV);
655         dasd_get_device(device);
656         return device;
657 }
658
659 /*
660  * Return dasd_device structure associated with cdev.
661  */
662 struct dasd_device *
663 dasd_device_from_cdev(struct ccw_device *cdev)
664 {
665         struct dasd_device *device;
666         unsigned long flags;
667
668         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
669         device = dasd_device_from_cdev_locked(cdev);
670         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
671         return device;
672 }
673
674 /*
675  * SECTION: files in sysfs
676  */
677
678 /*
679  * failfast controls the behaviour, if no path is available
680  */
681 static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
682                             char *buf)
683 {
684         struct dasd_devmap *devmap;
685         int ff_flag;
686
687         devmap = dasd_find_busid(dev_name(dev));
688         if (!IS_ERR(devmap))
689                 ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
690         else
691                 ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
692         return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
693 }
694
695 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
696               const char *buf, size_t count)
697 {
698         struct dasd_devmap *devmap;
699         int val;
700         char *endp;
701
702         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
703         if (IS_ERR(devmap))
704                 return PTR_ERR(devmap);
705
706         val = simple_strtoul(buf, &endp, 0);
707         if (((endp + 1) < (buf + count)) || (val > 1))
708                 return -EINVAL;
709
710         spin_lock(&dasd_devmap_lock);
711         if (val)
712                 devmap->features |= DASD_FEATURE_FAILFAST;
713         else
714                 devmap->features &= ~DASD_FEATURE_FAILFAST;
715         if (devmap->device)
716                 devmap->device->features = devmap->features;
717         spin_unlock(&dasd_devmap_lock);
718         return count;
719 }
720
721 static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
722
723 /*
724  * readonly controls the readonly status of a dasd
725  */
726 static ssize_t
727 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
728 {
729         struct dasd_devmap *devmap;
730         int ro_flag;
731
732         devmap = dasd_find_busid(dev_name(dev));
733         if (!IS_ERR(devmap))
734                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
735         else
736                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
737         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
738 }
739
740 static ssize_t
741 dasd_ro_store(struct device *dev, struct device_attribute *attr,
742               const char *buf, size_t count)
743 {
744         struct dasd_devmap *devmap;
745         int val;
746         char *endp;
747
748         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
749         if (IS_ERR(devmap))
750                 return PTR_ERR(devmap);
751
752         val = simple_strtoul(buf, &endp, 0);
753         if (((endp + 1) < (buf + count)) || (val > 1))
754                 return -EINVAL;
755
756         spin_lock(&dasd_devmap_lock);
757         if (val)
758                 devmap->features |= DASD_FEATURE_READONLY;
759         else
760                 devmap->features &= ~DASD_FEATURE_READONLY;
761         if (devmap->device)
762                 devmap->device->features = devmap->features;
763         if (devmap->device && devmap->device->block
764             && devmap->device->block->gdp)
765                 set_disk_ro(devmap->device->block->gdp, val);
766         spin_unlock(&dasd_devmap_lock);
767         return count;
768 }
769
770 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
771 /*
772  * erplog controls the logging of ERP related data
773  * (e.g. failing channel programs).
774  */
775 static ssize_t
776 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
777 {
778         struct dasd_devmap *devmap;
779         int erplog;
780
781         devmap = dasd_find_busid(dev_name(dev));
782         if (!IS_ERR(devmap))
783                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
784         else
785                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
786         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
787 }
788
789 static ssize_t
790 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
791               const char *buf, size_t count)
792 {
793         struct dasd_devmap *devmap;
794         int val;
795         char *endp;
796
797         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
798         if (IS_ERR(devmap))
799                 return PTR_ERR(devmap);
800
801         val = simple_strtoul(buf, &endp, 0);
802         if (((endp + 1) < (buf + count)) || (val > 1))
803                 return -EINVAL;
804
805         spin_lock(&dasd_devmap_lock);
806         if (val)
807                 devmap->features |= DASD_FEATURE_ERPLOG;
808         else
809                 devmap->features &= ~DASD_FEATURE_ERPLOG;
810         if (devmap->device)
811                 devmap->device->features = devmap->features;
812         spin_unlock(&dasd_devmap_lock);
813         return count;
814 }
815
816 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
817
818 /*
819  * use_diag controls whether the driver should use diag rather than ssch
820  * to talk to the device
821  */
822 static ssize_t
823 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
824 {
825         struct dasd_devmap *devmap;
826         int use_diag;
827
828         devmap = dasd_find_busid(dev_name(dev));
829         if (!IS_ERR(devmap))
830                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
831         else
832                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
833         return sprintf(buf, use_diag ? "1\n" : "0\n");
834 }
835
836 static ssize_t
837 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
838                     const char *buf, size_t count)
839 {
840         struct dasd_devmap *devmap;
841         ssize_t rc;
842         int val;
843         char *endp;
844
845         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
846         if (IS_ERR(devmap))
847                 return PTR_ERR(devmap);
848
849         val = simple_strtoul(buf, &endp, 0);
850         if (((endp + 1) < (buf + count)) || (val > 1))
851                 return -EINVAL;
852
853         spin_lock(&dasd_devmap_lock);
854         /* Changing diag discipline flag is only allowed in offline state. */
855         rc = count;
856         if (!devmap->device) {
857                 if (val)
858                         devmap->features |= DASD_FEATURE_USEDIAG;
859                 else
860                         devmap->features &= ~DASD_FEATURE_USEDIAG;
861         } else
862                 rc = -EPERM;
863         spin_unlock(&dasd_devmap_lock);
864         return rc;
865 }
866
867 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
868
869 static ssize_t
870 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
871                      char *buf)
872 {
873         struct dasd_device *device;
874         ssize_t len;
875
876         device = dasd_device_from_cdev(to_ccwdev(dev));
877         if (!IS_ERR(device) && device->discipline) {
878                 len = snprintf(buf, PAGE_SIZE, "%s\n",
879                                device->discipline->name);
880                 dasd_put_device(device);
881         } else
882                 len = snprintf(buf, PAGE_SIZE, "none\n");
883         return len;
884 }
885
886 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
887
888 static ssize_t
889 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
890                      char *buf)
891 {
892         struct dasd_device *device;
893         ssize_t len;
894
895         device = dasd_device_from_cdev(to_ccwdev(dev));
896         if (!IS_ERR(device)) {
897                 switch (device->state) {
898                 case DASD_STATE_NEW:
899                         len = snprintf(buf, PAGE_SIZE, "new\n");
900                         break;
901                 case DASD_STATE_KNOWN:
902                         len = snprintf(buf, PAGE_SIZE, "detected\n");
903                         break;
904                 case DASD_STATE_BASIC:
905                         len = snprintf(buf, PAGE_SIZE, "basic\n");
906                         break;
907                 case DASD_STATE_UNFMT:
908                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
909                         break;
910                 case DASD_STATE_READY:
911                         len = snprintf(buf, PAGE_SIZE, "ready\n");
912                         break;
913                 case DASD_STATE_ONLINE:
914                         len = snprintf(buf, PAGE_SIZE, "online\n");
915                         break;
916                 default:
917                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
918                         break;
919                 }
920                 dasd_put_device(device);
921         } else
922                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
923         return len;
924 }
925
926 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
927
928 static ssize_t
929 dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
930 {
931         struct dasd_devmap *devmap;
932         int alias;
933
934         devmap = dasd_find_busid(dev_name(dev));
935         spin_lock(&dasd_devmap_lock);
936         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
937                 spin_unlock(&dasd_devmap_lock);
938                 return sprintf(buf, "0\n");
939         }
940         if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
941             devmap->uid.type == UA_HYPER_PAV_ALIAS)
942                 alias = 1;
943         else
944                 alias = 0;
945         spin_unlock(&dasd_devmap_lock);
946         return sprintf(buf, alias ? "1\n" : "0\n");
947 }
948
949 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
950
951 static ssize_t
952 dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
953 {
954         struct dasd_devmap *devmap;
955         char *vendor;
956
957         devmap = dasd_find_busid(dev_name(dev));
958         spin_lock(&dasd_devmap_lock);
959         if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
960                 vendor = devmap->uid.vendor;
961         else
962                 vendor = "";
963         spin_unlock(&dasd_devmap_lock);
964
965         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
966 }
967
968 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
969
970 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
971                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
972                      /* vduit */ 32 + 1)
973
974 static ssize_t
975 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
976 {
977         struct dasd_devmap *devmap;
978         char uid_string[UID_STRLEN];
979         char ua_string[3];
980         struct dasd_uid *uid;
981
982         devmap = dasd_find_busid(dev_name(dev));
983         spin_lock(&dasd_devmap_lock);
984         if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
985                 spin_unlock(&dasd_devmap_lock);
986                 return sprintf(buf, "\n");
987         }
988         uid = &devmap->uid;
989         switch (uid->type) {
990         case UA_BASE_DEVICE:
991                 sprintf(ua_string, "%02x", uid->real_unit_addr);
992                 break;
993         case UA_BASE_PAV_ALIAS:
994                 sprintf(ua_string, "%02x", uid->base_unit_addr);
995                 break;
996         case UA_HYPER_PAV_ALIAS:
997                 sprintf(ua_string, "xx");
998                 break;
999         default:
1000                 /* should not happen, treat like base device */
1001                 sprintf(ua_string, "%02x", uid->real_unit_addr);
1002                 break;
1003         }
1004         if (strlen(uid->vduit) > 0)
1005                 snprintf(uid_string, sizeof(uid_string),
1006                          "%s.%s.%04x.%s.%s",
1007                          uid->vendor, uid->serial,
1008                          uid->ssid, ua_string,
1009                          uid->vduit);
1010         else
1011                 snprintf(uid_string, sizeof(uid_string),
1012                          "%s.%s.%04x.%s",
1013                          uid->vendor, uid->serial,
1014                          uid->ssid, ua_string);
1015         spin_unlock(&dasd_devmap_lock);
1016         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1017 }
1018
1019 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
1020
1021 /*
1022  * extended error-reporting
1023  */
1024 static ssize_t
1025 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
1026 {
1027         struct dasd_devmap *devmap;
1028         int eer_flag;
1029
1030         devmap = dasd_find_busid(dev_name(dev));
1031         if (!IS_ERR(devmap) && devmap->device)
1032                 eer_flag = dasd_eer_enabled(devmap->device);
1033         else
1034                 eer_flag = 0;
1035         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
1036 }
1037
1038 static ssize_t
1039 dasd_eer_store(struct device *dev, struct device_attribute *attr,
1040                const char *buf, size_t count)
1041 {
1042         struct dasd_devmap *devmap;
1043         int val, rc;
1044         char *endp;
1045
1046         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1047         if (IS_ERR(devmap))
1048                 return PTR_ERR(devmap);
1049         if (!devmap->device)
1050                 return -ENODEV;
1051
1052         val = simple_strtoul(buf, &endp, 0);
1053         if (((endp + 1) < (buf + count)) || (val > 1))
1054                 return -EINVAL;
1055
1056         if (val) {
1057                 rc = dasd_eer_enable(devmap->device);
1058                 if (rc)
1059                         return rc;
1060         } else
1061                 dasd_eer_disable(devmap->device);
1062         return count;
1063 }
1064
1065 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1066
1067 static struct attribute * dasd_attrs[] = {
1068         &dev_attr_readonly.attr,
1069         &dev_attr_discipline.attr,
1070         &dev_attr_status.attr,
1071         &dev_attr_alias.attr,
1072         &dev_attr_vendor.attr,
1073         &dev_attr_uid.attr,
1074         &dev_attr_use_diag.attr,
1075         &dev_attr_eer_enabled.attr,
1076         &dev_attr_erplog.attr,
1077         &dev_attr_failfast.attr,
1078         NULL,
1079 };
1080
1081 static struct attribute_group dasd_attr_group = {
1082         .attrs = dasd_attrs,
1083 };
1084
1085 /*
1086  * Return copy of the device unique identifier.
1087  */
1088 int
1089 dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1090 {
1091         struct dasd_devmap *devmap;
1092
1093         devmap = dasd_find_busid(dev_name(&cdev->dev));
1094         if (IS_ERR(devmap))
1095                 return PTR_ERR(devmap);
1096         spin_lock(&dasd_devmap_lock);
1097         *uid = devmap->uid;
1098         spin_unlock(&dasd_devmap_lock);
1099         return 0;
1100 }
1101
1102 /*
1103  * Register the given device unique identifier into devmap struct.
1104  * In addition check if the related storage server subsystem ID is already
1105  * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
1106  * create new entry.
1107  * Return 0 if server was already in serverlist,
1108  *        1 if the server was added successful
1109  *       <0 in case of error.
1110  */
1111 int
1112 dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
1113 {
1114         struct dasd_devmap *devmap;
1115
1116         devmap = dasd_find_busid(dev_name(&cdev->dev));
1117         if (IS_ERR(devmap))
1118                 return PTR_ERR(devmap);
1119
1120         spin_lock(&dasd_devmap_lock);
1121         devmap->uid = *uid;
1122         spin_unlock(&dasd_devmap_lock);
1123
1124         return 0;
1125 }
1126 EXPORT_SYMBOL_GPL(dasd_set_uid);
1127
1128 /*
1129  * Return value of the specified feature.
1130  */
1131 int
1132 dasd_get_feature(struct ccw_device *cdev, int feature)
1133 {
1134         struct dasd_devmap *devmap;
1135
1136         devmap = dasd_find_busid(dev_name(&cdev->dev));
1137         if (IS_ERR(devmap))
1138                 return PTR_ERR(devmap);
1139
1140         return ((devmap->features & feature) != 0);
1141 }
1142
1143 /*
1144  * Set / reset given feature.
1145  * Flag indicates wether to set (!=0) or the reset (=0) the feature.
1146  */
1147 int
1148 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1149 {
1150         struct dasd_devmap *devmap;
1151
1152         devmap = dasd_find_busid(dev_name(&cdev->dev));
1153         if (IS_ERR(devmap))
1154                 return PTR_ERR(devmap);
1155
1156         spin_lock(&dasd_devmap_lock);
1157         if (flag)
1158                 devmap->features |= feature;
1159         else
1160                 devmap->features &= ~feature;
1161         if (devmap->device)
1162                 devmap->device->features = devmap->features;
1163         spin_unlock(&dasd_devmap_lock);
1164         return 0;
1165 }
1166
1167
1168 int
1169 dasd_add_sysfs_files(struct ccw_device *cdev)
1170 {
1171         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1172 }
1173
1174 void
1175 dasd_remove_sysfs_files(struct ccw_device *cdev)
1176 {
1177         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1178 }
1179
1180
1181 int
1182 dasd_devmap_init(void)
1183 {
1184         int i;
1185
1186         /* Initialize devmap structures. */
1187         dasd_max_devindex = 0;
1188         for (i = 0; i < 256; i++)
1189                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1190         return 0;
1191 }
1192
1193 void
1194 dasd_devmap_exit(void)
1195 {
1196         dasd_forget_ranges();
1197 }