drivers/s390/block/dasd_devmap.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   4  *                  Carsten Otte <Cotte@de.ibm.com>
   5  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * Copyright IBM Corp. 1999,2001
   8  *
   9  * Device mapping and dasd= parameter parsing functions. All devmap
  10  * functions may not be called from interrupt context. In particular
  11  * dasd_get_device is a no-no from interrupt context.
  12  *
  13  */
  14
  15 #define KMSG_COMPONENT "dasd"
  16
  17 #include <linux/ctype.h>
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/slab.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 };
  52
  53 /*
  54  * Parameter parsing functions for dasd= parameter. The syntax is:
  55  *   <devno>            : (0x)?[0-9a-fA-F]+
  56  *   <busid>            : [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
  57  *   <feature>          : ro
  58  *   <feature_list>     : \(<feature>(:<feature>)*\)
  59  *   <devno-range>      : <devno>(-<devno>)?<feature_list>?
  60  *   <busid-range>      : <busid>(-<busid>)?<feature_list>?
  61  *   <devices>          : <devno-range>|<busid-range>
  62  *   <dasd_module>      : dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
  63  *
  64  *   <dasd>             : autodetect|probeonly|<devices>(,<devices>)*
  65  */
  66
  67 int dasd_probeonly =  0;        /* is true, when probeonly mode is active */
  68 int dasd_autodetect = 0;        /* is true, when autodetection is active */
  69 int dasd_nopav = 0;             /* is true, when PAV is disabled */
  70 EXPORT_SYMBOL_GPL(dasd_nopav);
  71 int dasd_nofcx;                 /* disable High Performance Ficon */
  72 EXPORT_SYMBOL_GPL(dasd_nofcx);
  73
  74 /*
  75  * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
  76  * it is named 'dasd' to directly be filled by insmod with the comma separated
  77  * strings when running as a module.
  78  */
  79 static char *dasd[256];
  80 module_param_array(dasd, charp, NULL, 0);
  81
  82 /*
  83  * Single spinlock to protect devmap and servermap structures and lists.
  84  */
  85 static DEFINE_SPINLOCK(dasd_devmap_lock);
  86
  87 /*
  88  * Hash lists for devmap structures.
  89  */
  90 static struct list_head dasd_hashlists[256];
  91 int dasd_max_devindex;
  92
  93 static struct dasd_devmap *dasd_add_busid(const char *, int);
  94
  95 static inline int
  96 dasd_hash_busid(const char *bus_id)
  97 {
  98         int hash, i;
  99
 100         hash = 0;
 101         for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
 102                 hash += *bus_id;
 103         return hash & 0xff;
 104 }
 105
 106 #ifndef MODULE
 107 /*
 108  * The parameter parsing functions for builtin-drivers are called
 109  * before kmalloc works. Store the pointers to the parameters strings
 110  * into dasd[] for later processing.
 111  */
 112 static int __init
 113 dasd_call_setup(char *str)
 114 {
 115         static int count = 0;
 116
 117         if (count < 256)
 118                 dasd[count++] = str;
 119         return 1;
 120 }
 121
 122 __setup ("dasd=", dasd_call_setup);
 123 #endif  /* #ifndef MODULE */
 124
 125 #define DASD_IPLDEV     "ipldev"
 126
 127 /*
 128  * Read a device busid/devno from a string.
 129  */
 130 static int
 131
 132 dasd_busid(char **str, int *id0, int *id1, int *devno)
 133 {
 134         int val, old_style;
 135
 136         /* Interpret ipldev busid */
 137         if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
 138                 if (ipl_info.type != IPL_TYPE_CCW) {
 139                         pr_err("The IPL device is not a CCW device\n");
 140                         return -EINVAL;
 141                 }
 142                 *id0 = 0;
 143                 *id1 = ipl_info.data.ccw.dev_id.ssid;
 144                 *devno = ipl_info.data.ccw.dev_id.devno;
 145                 *str += strlen(DASD_IPLDEV);
 146
 147                 return 0;
 148         }
 149         /* check for leading '0x' */
 150         old_style = 0;
 151         if ((*str)[0] == '0' && (*str)[1] == 'x') {
 152                 *str += 2;
 153                 old_style = 1;
 154         }
 155         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 156                 return -EINVAL;
 157         val = simple_strtoul(*str, str, 16);
 158         if (old_style || (*str)[0] != '.') {
 159                 *id0 = *id1 = 0;
 160                 if (val < 0 || val > 0xffff)
 161                         return -EINVAL;
 162                 *devno = val;
 163                 return 0;
 164         }
 165         /* New style x.y.z busid */
 166         if (val < 0 || val > 0xff)
 167                 return -EINVAL;
 168         *id0 = val;
 169         (*str)++;
 170         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 171                 return -EINVAL;
 172         val = simple_strtoul(*str, str, 16);
 173         if (val < 0 || val > 0xff || (*str)++[0] != '.')
 174                 return -EINVAL;
 175         *id1 = val;
 176         if (!isxdigit((*str)[0]))       /* We require at least one hex digit */
 177                 return -EINVAL;
 178         val = simple_strtoul(*str, str, 16);
 179         if (val < 0 || val > 0xffff)
 180                 return -EINVAL;
 181         *devno = val;
 182         return 0;
 183 }
 184
 185 /*
 186  * Read colon separated list of dasd features. Currently there is
 187  * only one: "ro" for read-only devices. The default feature set
 188  * is empty (value 0).
 189  */
 190 static int
 191 dasd_feature_list(char *str, char **endp)
 192 {
 193         int features, len, rc;
 194
 195         rc = 0;
 196         if (*str != '(') {
 197                 *endp = str;
 198                 return DASD_FEATURE_DEFAULT;
 199         }
 200         str++;
 201         features = 0;
 202
 203         while (1) {
 204                 for (len = 0;
 205                      str[len] && str[len] != ':' && str[len] != ')'; len++);
 206                 if (len == 2 && !strncmp(str, "ro", 2))
 207                         features |= DASD_FEATURE_READONLY;
 208                 else if (len == 4 && !strncmp(str, "diag", 4))
 209                         features |= DASD_FEATURE_USEDIAG;
 210                 else if (len == 3 && !strncmp(str, "raw", 3))
 211                         features |= DASD_FEATURE_USERAW;
 212                 else if (len == 6 && !strncmp(str, "erplog", 6))
 213                         features |= DASD_FEATURE_ERPLOG;
 214                 else if (len == 8 && !strncmp(str, "failfast", 8))
 215                         features |= DASD_FEATURE_FAILFAST;
 216                 else {
 217                         pr_warning("%*s is not a supported device option\n",
 218                                    len, str);
 219                         rc = -EINVAL;
 220                 }
 221                 str += len;
 222                 if (*str != ':')
 223                         break;
 224                 str++;
 225         }
 226         if (*str != ')') {
 227                 pr_warning("A closing parenthesis ')' is missing in the "
 228                            "dasd= parameter\n");
 229                 rc = -EINVAL;
 230         } else
 231                 str++;
 232         *endp = str;
 233         if (rc != 0)
 234                 return rc;
 235         return features;
 236 }
 237
 238 /*
 239  * Try to match the first element on the comma separated parse string
 240  * with one of the known keywords. If a keyword is found, take the approprate
 241  * action and return a pointer to the residual string. If the first element
 242  * could not be matched to any keyword then return an error code.
 243  */
 244 static char *
 245 dasd_parse_keyword( char *parsestring ) {
 246
 247         char *nextcomma, *residual_str;
 248         int length;
 249
 250         nextcomma = strchr(parsestring,',');
 251         if (nextcomma) {
 252                 length = nextcomma - parsestring;
 253                 residual_str = nextcomma + 1;
 254         } else {
 255                 length = strlen(parsestring);
 256                 residual_str = parsestring + length;
 257         }
 258         if (strncmp("autodetect", parsestring, length) == 0) {
 259                 dasd_autodetect = 1;
 260                 pr_info("The autodetection mode has been activated\n");
 261                 return residual_str;
 262         }
 263         if (strncmp("probeonly", parsestring, length) == 0) {
 264                 dasd_probeonly = 1;
 265                 pr_info("The probeonly mode has been activated\n");
 266                 return residual_str;
 267         }
 268         if (strncmp("nopav", parsestring, length) == 0) {
 269                 if (MACHINE_IS_VM)
 270                         pr_info("'nopav' is not supported on z/VM\n");
 271                 else {
 272                         dasd_nopav = 1;
 273                         pr_info("PAV support has be deactivated\n");
 274                 }
 275                 return residual_str;
 276         }
 277         if (strncmp("nofcx", parsestring, length) == 0) {
 278                 dasd_nofcx = 1;
 279                 pr_info("High Performance FICON support has been "
 280                         "deactivated\n");
 281                 return residual_str;
 282         }
 283         if (strncmp("fixedbuffers", parsestring, length) == 0) {
 284                 if (dasd_page_cache)
 285                         return residual_str;
 286                 dasd_page_cache =
 287                         kmem_cache_create("dasd_page_cache", PAGE_SIZE,
 288                                           PAGE_SIZE, SLAB_CACHE_DMA,
 289                                           NULL);
 290                 if (!dasd_page_cache)
 291                         DBF_EVENT(DBF_WARNING, "%s", "Failed to create slab, "
 292                                 "fixed buffer mode disabled.");
 293                 else
 294                         DBF_EVENT(DBF_INFO, "%s",
 295                                  "turning on fixed buffer mode");
 296                 return residual_str;
 297         }
 298         return ERR_PTR(-EINVAL);
 299 }
 300
 301 /*
 302  * Try to interprete the first element on the comma separated parse string
 303  * as a device number or a range of devices. If the interpretation is
 304  * successful, create the matching dasd_devmap entries and return a pointer
 305  * to the residual string.
 306  * If interpretation fails or in case of an error, return an error code.
 307  */
 308 static char *
 309 dasd_parse_range( char *parsestring ) {
 310
 311         struct dasd_devmap *devmap;
 312         int from, from_id0, from_id1;
 313         int to, to_id0, to_id1;
 314         int features, rc;
 315         char bus_id[DASD_BUS_ID_SIZE+1], *str;
 316
 317         str = parsestring;
 318         rc = dasd_busid(&str, &from_id0, &from_id1, &from);
 319         if (rc == 0) {
 320                 to = from;
 321                 to_id0 = from_id0;
 322                 to_id1 = from_id1;
 323                 if (*str == '-') {
 324                         str++;
 325                         rc = dasd_busid(&str, &to_id0, &to_id1, &to);
 326                 }
 327         }
 328         if (rc == 0 &&
 329             (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
 330                 rc = -EINVAL;
 331         if (rc) {
 332                 pr_err("%s is not a valid device range\n", parsestring);
 333                 return ERR_PTR(rc);
 334         }
 335         features = dasd_feature_list(str, &str);
 336         if (features < 0)
 337                 return ERR_PTR(-EINVAL);
 338         /* each device in dasd= parameter should be set initially online */
 339         features |= DASD_FEATURE_INITIAL_ONLINE;
 340         while (from <= to) {
 341                 sprintf(bus_id, "%01x.%01x.%04x",
 342                         from_id0, from_id1, from++);
 343                 devmap = dasd_add_busid(bus_id, features);
 344                 if (IS_ERR(devmap))
 345                         return (char *)devmap;
 346         }
 347         if (*str == ',')
 348                 return str + 1;
 349         if (*str == '\0')
 350                 return str;
 351         pr_warning("The dasd= parameter value %s has an invalid ending\n",
 352                    str);
 353         return ERR_PTR(-EINVAL);
 354 }
 355
 356 static char *
 357 dasd_parse_next_element( char *parsestring ) {
 358         char * residual_str;
 359         residual_str = dasd_parse_keyword(parsestring);
 360         if (!IS_ERR(residual_str))
 361                 return residual_str;
 362         residual_str = dasd_parse_range(parsestring);
 363         return residual_str;
 364 }
 365
 366 /*
 367  * Parse parameters stored in dasd[]
 368  * The 'dasd=...' parameter allows to specify a comma separated list of
 369  * keywords and device ranges. When the dasd driver is build into the kernel,
 370  * the complete list will be stored as one element of the dasd[] array.
 371  * When the dasd driver is build as a module, then the list is broken into
 372  * it's elements and each dasd[] entry contains one element.
 373  */
 374 int
 375 dasd_parse(void)
 376 {
 377         int rc, i;
 378         char *parsestring;
 379
 380         rc = 0;
 381         for (i = 0; i < 256; i++) {
 382                 if (dasd[i] == NULL)
 383                         break;
 384                 parsestring = dasd[i];
 385                 /* loop over the comma separated list in the parsestring */
 386                 while (*parsestring) {
 387                         parsestring = dasd_parse_next_element(parsestring);
 388                         if(IS_ERR(parsestring)) {
 389                                 rc = PTR_ERR(parsestring);
 390                                 break;
 391                         }
 392                 }
 393                 if (rc) {
 394                         DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
 395                         break;
 396                 }
 397         }
 398         return rc;
 399 }
 400
 401 /*
 402  * Add a devmap for the device specified by busid. It is possible that
 403  * the devmap already exists (dasd= parameter). The order of the devices
 404  * added through this function will define the kdevs for the individual
 405  * devices.
 406  */
 407 static struct dasd_devmap *
 408 dasd_add_busid(const char *bus_id, int features)
 409 {
 410         struct dasd_devmap *devmap, *new, *tmp;
 411         int hash;
 412
 413         new = (struct dasd_devmap *)
 414                 kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
 415         if (!new)
 416                 return ERR_PTR(-ENOMEM);
 417         spin_lock(&dasd_devmap_lock);
 418         devmap = NULL;
 419         hash = dasd_hash_busid(bus_id);
 420         list_for_each_entry(tmp, &dasd_hashlists[hash], list)
 421                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 422                         devmap = tmp;
 423                         break;
 424                 }
 425         if (!devmap) {
 426                 /* This bus_id is new. */
 427                 new->devindex = dasd_max_devindex++;
 428                 strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
 429                 new->features = features;
 430                 new->device = NULL;
 431                 list_add(&new->list, &dasd_hashlists[hash]);
 432                 devmap = new;
 433                 new = NULL;
 434         }
 435         spin_unlock(&dasd_devmap_lock);
 436         kfree(new);
 437         return devmap;
 438 }
 439
 440 /*
 441  * Find devmap for device with given bus_id.
 442  */
 443 static struct dasd_devmap *
 444 dasd_find_busid(const char *bus_id)
 445 {
 446         struct dasd_devmap *devmap, *tmp;
 447         int hash;
 448
 449         spin_lock(&dasd_devmap_lock);
 450         devmap = ERR_PTR(-ENODEV);
 451         hash = dasd_hash_busid(bus_id);
 452         list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
 453                 if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
 454                         devmap = tmp;
 455                         break;
 456                 }
 457         }
 458         spin_unlock(&dasd_devmap_lock);
 459         return devmap;
 460 }
 461
 462 /*
 463  * Check if busid has been added to the list of dasd ranges.
 464  */
 465 int
 466 dasd_busid_known(const char *bus_id)
 467 {
 468         return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
 469 }
 470
 471 /*
 472  * Forget all about the device numbers added so far.
 473  * This may only be called at module unload or system shutdown.
 474  */
 475 static void
 476 dasd_forget_ranges(void)
 477 {
 478         struct dasd_devmap *devmap, *n;
 479         int i;
 480
 481         spin_lock(&dasd_devmap_lock);
 482         for (i = 0; i < 256; i++) {
 483                 list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
 484                         BUG_ON(devmap->device != NULL);
 485                         list_del(&devmap->list);
 486                         kfree(devmap);
 487                 }
 488         }
 489         spin_unlock(&dasd_devmap_lock);
 490 }
 491
 492 /*
 493  * Find the device struct by its device index.
 494  */
 495 struct dasd_device *
 496 dasd_device_from_devindex(int devindex)
 497 {
 498         struct dasd_devmap *devmap, *tmp;
 499         struct dasd_device *device;
 500         int i;
 501
 502         spin_lock(&dasd_devmap_lock);
 503         devmap = NULL;
 504         for (i = 0; (i < 256) && !devmap; i++)
 505                 list_for_each_entry(tmp, &dasd_hashlists[i], list)
 506                         if (tmp->devindex == devindex) {
 507                                 /* Found the devmap for the device. */
 508                                 devmap = tmp;
 509                                 break;
 510                         }
 511         if (devmap && devmap->device) {
 512                 device = devmap->device;
 513                 dasd_get_device(device);
 514         } else
 515                 device = ERR_PTR(-ENODEV);
 516         spin_unlock(&dasd_devmap_lock);
 517         return device;
 518 }
 519
 520 /*
 521  * Return devmap for cdev. If no devmap exists yet, create one and
 522  * connect it to the cdev.
 523  */
 524 static struct dasd_devmap *
 525 dasd_devmap_from_cdev(struct ccw_device *cdev)
 526 {
 527         struct dasd_devmap *devmap;
 528
 529         devmap = dasd_find_busid(dev_name(&cdev->dev));
 530         if (IS_ERR(devmap))
 531                 devmap = dasd_add_busid(dev_name(&cdev->dev),
 532                                         DASD_FEATURE_DEFAULT);
 533         return devmap;
 534 }
 535
 536 /*
 537  * Create a dasd device structure for cdev.
 538  */
 539 struct dasd_device *
 540 dasd_create_device(struct ccw_device *cdev)
 541 {
 542         struct dasd_devmap *devmap;
 543         struct dasd_device *device;
 544         unsigned long flags;
 545         int rc;
 546
 547         devmap = dasd_devmap_from_cdev(cdev);
 548         if (IS_ERR(devmap))
 549                 return (void *) devmap;
 550
 551         device = dasd_alloc_device();
 552         if (IS_ERR(device))
 553                 return device;
 554         atomic_set(&device->ref_count, 3);
 555
 556         spin_lock(&dasd_devmap_lock);
 557         if (!devmap->device) {
 558                 devmap->device = device;
 559                 device->devindex = devmap->devindex;
 560                 device->features = devmap->features;
 561                 get_device(&cdev->dev);
 562                 device->cdev = cdev;
 563                 rc = 0;
 564         } else
 565                 /* Someone else was faster. */
 566                 rc = -EBUSY;
 567         spin_unlock(&dasd_devmap_lock);
 568
 569         if (rc) {
 570                 dasd_free_device(device);
 571                 return ERR_PTR(rc);
 572         }
 573
 574         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 575         dev_set_drvdata(&cdev->dev, device);
 576         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 577
 578         return device;
 579 }
 580
 581 /*
 582  * Wait queue for dasd_delete_device waits.
 583  */
 584 static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
 585
 586 /*
 587  * Remove a dasd device structure. The passed referenced
 588  * is destroyed.
 589  */
 590 void
 591 dasd_delete_device(struct dasd_device *device)
 592 {
 593         struct ccw_device *cdev;
 594         struct dasd_devmap *devmap;
 595         unsigned long flags;
 596
 597         /* First remove device pointer from devmap. */
 598         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
 599         BUG_ON(IS_ERR(devmap));
 600         spin_lock(&dasd_devmap_lock);
 601         if (devmap->device != device) {
 602                 spin_unlock(&dasd_devmap_lock);
 603                 dasd_put_device(device);
 604                 return;
 605         }
 606         devmap->device = NULL;
 607         spin_unlock(&dasd_devmap_lock);
 608
 609         /* Disconnect dasd_device structure from ccw_device structure. */
 610         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 611         dev_set_drvdata(&device->cdev->dev, NULL);
 612         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 613
 614         /*
 615          * Drop ref_count by 3, one for the devmap reference, one for
 616          * the cdev reference and one for the passed reference.
 617          */
 618         atomic_sub(3, &device->ref_count);
 619
 620         /* Wait for reference counter to drop to zero. */
 621         wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
 622
 623         /* Disconnect dasd_device structure from ccw_device structure. */
 624         cdev = device->cdev;
 625         device->cdev = NULL;
 626
 627         /* Put ccw_device structure. */
 628         put_device(&cdev->dev);
 629
 630         /* Now the device structure can be freed. */
 631         dasd_free_device(device);
 632 }
 633
 634 /*
 635  * Reference counter dropped to zero. Wake up waiter
 636  * in dasd_delete_device.
 637  */
 638 void
 639 dasd_put_device_wake(struct dasd_device *device)
 640 {
 641         wake_up(&dasd_delete_wq);
 642 }
 643 EXPORT_SYMBOL_GPL(dasd_put_device_wake);
 644
 645 /*
 646  * Return dasd_device structure associated with cdev.
 647  * This function needs to be called with the ccw device
 648  * lock held. It can be used from interrupt context.
 649  */
 650 struct dasd_device *
 651 dasd_device_from_cdev_locked(struct ccw_device *cdev)
 652 {
 653         struct dasd_device *device = dev_get_drvdata(&cdev->dev);
 654
 655         if (!device)
 656                 return ERR_PTR(-ENODEV);
 657         dasd_get_device(device);
 658         return device;
 659 }
 660
 661 /*
 662  * Return dasd_device structure associated with cdev.
 663  */
 664 struct dasd_device *
 665 dasd_device_from_cdev(struct ccw_device *cdev)
 666 {
 667         struct dasd_device *device;
 668         unsigned long flags;
 669
 670         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 671         device = dasd_device_from_cdev_locked(cdev);
 672         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
 673         return device;
 674 }
 675
 676 void dasd_add_link_to_gendisk(struct gendisk *gdp, struct dasd_device *device)
 677 {
 678         struct dasd_devmap *devmap;
 679
 680         devmap = dasd_find_busid(dev_name(&device->cdev->dev));
 681         if (IS_ERR(devmap))
 682                 return;
 683         spin_lock(&dasd_devmap_lock);
 684         gdp->private_data = devmap;
 685         spin_unlock(&dasd_devmap_lock);
 686 }
 687
 688 struct dasd_device *dasd_device_from_gendisk(struct gendisk *gdp)
 689 {
 690         struct dasd_device *device;
 691         struct dasd_devmap *devmap;
 692
 693         if (!gdp->private_data)
 694                 return NULL;
 695         device = NULL;
 696         spin_lock(&dasd_devmap_lock);
 697         devmap = gdp->private_data;
 698         if (devmap && devmap->device) {
 699                 device = devmap->device;
 700                 dasd_get_device(device);
 701         }
 702         spin_unlock(&dasd_devmap_lock);
 703         return device;
 704 }
 705
 706 /*
 707  * SECTION: files in sysfs
 708  */
 709
 710 /*
 711  * failfast controls the behaviour, if no path is available
 712  */
 713 static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
 714                             char *buf)
 715 {
 716         struct dasd_devmap *devmap;
 717         int ff_flag;
 718
 719         devmap = dasd_find_busid(dev_name(dev));
 720         if (!IS_ERR(devmap))
 721                 ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
 722         else
 723                 ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
 724         return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
 725 }
 726
 727 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
 728               const char *buf, size_t count)
 729 {
 730         struct dasd_devmap *devmap;
 731         int val;
 732         char *endp;
 733
 734         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 735         if (IS_ERR(devmap))
 736                 return PTR_ERR(devmap);
 737
 738         val = simple_strtoul(buf, &endp, 0);
 739         if (((endp + 1) < (buf + count)) || (val > 1))
 740                 return -EINVAL;
 741
 742         spin_lock(&dasd_devmap_lock);
 743         if (val)
 744                 devmap->features |= DASD_FEATURE_FAILFAST;
 745         else
 746                 devmap->features &= ~DASD_FEATURE_FAILFAST;
 747         if (devmap->device)
 748                 devmap->device->features = devmap->features;
 749         spin_unlock(&dasd_devmap_lock);
 750         return count;
 751 }
 752
 753 static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
 754
 755 /*
 756  * readonly controls the readonly status of a dasd
 757  */
 758 static ssize_t
 759 dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
 760 {
 761         struct dasd_devmap *devmap;
 762         int ro_flag;
 763
 764         devmap = dasd_find_busid(dev_name(dev));
 765         if (!IS_ERR(devmap))
 766                 ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
 767         else
 768                 ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
 769         return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
 770 }
 771
 772 static ssize_t
 773 dasd_ro_store(struct device *dev, struct device_attribute *attr,
 774               const char *buf, size_t count)
 775 {
 776         struct dasd_devmap *devmap;
 777         struct dasd_device *device;
 778         int val;
 779         char *endp;
 780
 781         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 782         if (IS_ERR(devmap))
 783                 return PTR_ERR(devmap);
 784
 785         val = simple_strtoul(buf, &endp, 0);
 786         if (((endp + 1) < (buf + count)) || (val > 1))
 787                 return -EINVAL;
 788
 789         spin_lock(&dasd_devmap_lock);
 790         if (val)
 791                 devmap->features |= DASD_FEATURE_READONLY;
 792         else
 793                 devmap->features &= ~DASD_FEATURE_READONLY;
 794         device = devmap->device;
 795         if (device) {
 796                 device->features = devmap->features;
 797                 val = val || test_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 798         }
 799         spin_unlock(&dasd_devmap_lock);
 800         if (device && device->block && device->block->gdp)
 801                 set_disk_ro(device->block->gdp, val);
 802         return count;
 803 }
 804
 805 static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
 806 /*
 807  * erplog controls the logging of ERP related data
 808  * (e.g. failing channel programs).
 809  */
 810 static ssize_t
 811 dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
 812 {
 813         struct dasd_devmap *devmap;
 814         int erplog;
 815
 816         devmap = dasd_find_busid(dev_name(dev));
 817         if (!IS_ERR(devmap))
 818                 erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
 819         else
 820                 erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
 821         return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
 822 }
 823
 824 static ssize_t
 825 dasd_erplog_store(struct device *dev, struct device_attribute *attr,
 826               const char *buf, size_t count)
 827 {
 828         struct dasd_devmap *devmap;
 829         int val;
 830         char *endp;
 831
 832         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 833         if (IS_ERR(devmap))
 834                 return PTR_ERR(devmap);
 835
 836         val = simple_strtoul(buf, &endp, 0);
 837         if (((endp + 1) < (buf + count)) || (val > 1))
 838                 return -EINVAL;
 839
 840         spin_lock(&dasd_devmap_lock);
 841         if (val)
 842                 devmap->features |= DASD_FEATURE_ERPLOG;
 843         else
 844                 devmap->features &= ~DASD_FEATURE_ERPLOG;
 845         if (devmap->device)
 846                 devmap->device->features = devmap->features;
 847         spin_unlock(&dasd_devmap_lock);
 848         return count;
 849 }
 850
 851 static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
 852
 853 /*
 854  * use_diag controls whether the driver should use diag rather than ssch
 855  * to talk to the device
 856  */
 857 static ssize_t
 858 dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
 859 {
 860         struct dasd_devmap *devmap;
 861         int use_diag;
 862
 863         devmap = dasd_find_busid(dev_name(dev));
 864         if (!IS_ERR(devmap))
 865                 use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
 866         else
 867                 use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
 868         return sprintf(buf, use_diag ? "1\n" : "0\n");
 869 }
 870
 871 static ssize_t
 872 dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
 873                     const char *buf, size_t count)
 874 {
 875         struct dasd_devmap *devmap;
 876         ssize_t rc;
 877         int val;
 878         char *endp;
 879
 880         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 881         if (IS_ERR(devmap))
 882                 return PTR_ERR(devmap);
 883
 884         val = simple_strtoul(buf, &endp, 0);
 885         if (((endp + 1) < (buf + count)) || (val > 1))
 886                 return -EINVAL;
 887
 888         spin_lock(&dasd_devmap_lock);
 889         /* Changing diag discipline flag is only allowed in offline state. */
 890         rc = count;
 891         if (!devmap->device && !(devmap->features & DASD_FEATURE_USERAW)) {
 892                 if (val)
 893                         devmap->features |= DASD_FEATURE_USEDIAG;
 894                 else
 895                         devmap->features &= ~DASD_FEATURE_USEDIAG;
 896         } else
 897                 rc = -EPERM;
 898         spin_unlock(&dasd_devmap_lock);
 899         return rc;
 900 }
 901
 902 static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
 903
 904 /*
 905  * use_raw controls whether the driver should give access to raw eckd data or
 906  * operate in standard mode
 907  */
 908 static ssize_t
 909 dasd_use_raw_show(struct device *dev, struct device_attribute *attr, char *buf)
 910 {
 911         struct dasd_devmap *devmap;
 912         int use_raw;
 913
 914         devmap = dasd_find_busid(dev_name(dev));
 915         if (!IS_ERR(devmap))
 916                 use_raw = (devmap->features & DASD_FEATURE_USERAW) != 0;
 917         else
 918                 use_raw = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USERAW) != 0;
 919         return sprintf(buf, use_raw ? "1\n" : "0\n");
 920 }
 921
 922 static ssize_t
 923 dasd_use_raw_store(struct device *dev, struct device_attribute *attr,
 924                     const char *buf, size_t count)
 925 {
 926         struct dasd_devmap *devmap;
 927         ssize_t rc;
 928         unsigned long val;
 929
 930         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
 931         if (IS_ERR(devmap))
 932                 return PTR_ERR(devmap);
 933
 934         if ((strict_strtoul(buf, 10, &val) != 0) || val > 1)
 935                 return -EINVAL;
 936
 937         spin_lock(&dasd_devmap_lock);
 938         /* Changing diag discipline flag is only allowed in offline state. */
 939         rc = count;
 940         if (!devmap->device && !(devmap->features & DASD_FEATURE_USEDIAG)) {
 941                 if (val)
 942                         devmap->features |= DASD_FEATURE_USERAW;
 943                 else
 944                         devmap->features &= ~DASD_FEATURE_USERAW;
 945         } else
 946                 rc = -EPERM;
 947         spin_unlock(&dasd_devmap_lock);
 948         return rc;
 949 }
 950
 951 static DEVICE_ATTR(raw_track_access, 0644, dasd_use_raw_show,
 952                    dasd_use_raw_store);
 953
 954 static ssize_t
 955 dasd_safe_offline_store(struct device *dev, struct device_attribute *attr,
 956                         const char *buf, size_t count)
 957 {
 958         struct ccw_device *cdev = to_ccwdev(dev);
 959         struct dasd_device *device;
 960         int rc;
 961
 962         device = dasd_device_from_cdev(cdev);
 963         if (IS_ERR(device)) {
 964                 rc = PTR_ERR(device);
 965                 goto out;
 966         }
 967
 968         if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
 969             test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
 970                 /* Already doing offline processing */
 971                 dasd_put_device(device);
 972                 rc = -EBUSY;
 973                 goto out;
 974         }
 975
 976         set_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags);
 977         dasd_put_device(device);
 978
 979         rc = ccw_device_set_offline(cdev);
 980
 981 out:
 982         return rc ? rc : count;
 983 }
 984
 985 static DEVICE_ATTR(safe_offline, 0200, NULL, dasd_safe_offline_store);
 986
 987 static ssize_t
 988 dasd_discipline_show(struct device *dev, struct device_attribute *attr,
 989                      char *buf)
 990 {
 991         struct dasd_device *device;
 992         ssize_t len;
 993
 994         device = dasd_device_from_cdev(to_ccwdev(dev));
 995         if (IS_ERR(device))
 996                 goto out;
 997         else if (!device->discipline) {
 998                 dasd_put_device(device);
 999                 goto out;
1000         } else {
1001                 len = snprintf(buf, PAGE_SIZE, "%s\n",
1002                                device->discipline->name);
1003                 dasd_put_device(device);
1004                 return len;
1005         }
1006 out:
1007         len = snprintf(buf, PAGE_SIZE, "none\n");
1008         return len;
1009 }
1010
1011 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
1012
1013 static ssize_t
1014 dasd_device_status_show(struct device *dev, struct device_attribute *attr,
1015                      char *buf)
1016 {
1017         struct dasd_device *device;
1018         ssize_t len;
1019
1020         device = dasd_device_from_cdev(to_ccwdev(dev));
1021         if (!IS_ERR(device)) {
1022                 switch (device->state) {
1023                 case DASD_STATE_NEW:
1024                         len = snprintf(buf, PAGE_SIZE, "new\n");
1025                         break;
1026                 case DASD_STATE_KNOWN:
1027                         len = snprintf(buf, PAGE_SIZE, "detected\n");
1028                         break;
1029                 case DASD_STATE_BASIC:
1030                         len = snprintf(buf, PAGE_SIZE, "basic\n");
1031                         break;
1032                 case DASD_STATE_UNFMT:
1033                         len = snprintf(buf, PAGE_SIZE, "unformatted\n");
1034                         break;
1035                 case DASD_STATE_READY:
1036                         len = snprintf(buf, PAGE_SIZE, "ready\n");
1037                         break;
1038                 case DASD_STATE_ONLINE:
1039                         len = snprintf(buf, PAGE_SIZE, "online\n");
1040                         break;
1041                 default:
1042                         len = snprintf(buf, PAGE_SIZE, "no stat\n");
1043                         break;
1044                 }
1045                 dasd_put_device(device);
1046         } else
1047                 len = snprintf(buf, PAGE_SIZE, "unknown\n");
1048         return len;
1049 }
1050
1051 static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
1052
1053 static ssize_t dasd_alias_show(struct device *dev,
1054                                struct device_attribute *attr, char *buf)
1055 {
1056         struct dasd_device *device;
1057         struct dasd_uid uid;
1058
1059         device = dasd_device_from_cdev(to_ccwdev(dev));
1060         if (IS_ERR(device))
1061                 return sprintf(buf, "0\n");
1062
1063         if (device->discipline && device->discipline->get_uid &&
1064             !device->discipline->get_uid(device, &uid)) {
1065                 if (uid.type == UA_BASE_PAV_ALIAS ||
1066                     uid.type == UA_HYPER_PAV_ALIAS) {
1067                         dasd_put_device(device);
1068                         return sprintf(buf, "1\n");
1069                 }
1070         }
1071         dasd_put_device(device);
1072
1073         return sprintf(buf, "0\n");
1074 }
1075
1076 static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
1077
1078 static ssize_t dasd_vendor_show(struct device *dev,
1079                                 struct device_attribute *attr, char *buf)
1080 {
1081         struct dasd_device *device;
1082         struct dasd_uid uid;
1083         char *vendor;
1084
1085         device = dasd_device_from_cdev(to_ccwdev(dev));
1086         vendor = "";
1087         if (IS_ERR(device))
1088                 return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
1089
1090         if (device->discipline && device->discipline->get_uid &&
1091             !device->discipline->get_uid(device, &uid))
1092                         vendor = uid.vendor;
1093
1094         dasd_put_device(device);
1095
1096         return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
1097 }
1098
1099 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
1100
1101 #define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
1102                      /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
1103                      /* vduit */ 32 + 1)
1104
1105 static ssize_t
1106 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
1107 {
1108         struct dasd_device *device;
1109         struct dasd_uid uid;
1110         char uid_string[UID_STRLEN];
1111         char ua_string[3];
1112
1113         device = dasd_device_from_cdev(to_ccwdev(dev));
1114         uid_string[0] = 0;
1115         if (IS_ERR(device))
1116                 return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1117
1118         if (device->discipline && device->discipline->get_uid &&
1119             !device->discipline->get_uid(device, &uid)) {
1120                 switch (uid.type) {
1121                 case UA_BASE_DEVICE:
1122                         snprintf(ua_string, sizeof(ua_string), "%02x",
1123                                  uid.real_unit_addr);
1124                         break;
1125                 case UA_BASE_PAV_ALIAS:
1126                         snprintf(ua_string, sizeof(ua_string), "%02x",
1127                                  uid.base_unit_addr);
1128                         break;
1129                 case UA_HYPER_PAV_ALIAS:
1130                         snprintf(ua_string, sizeof(ua_string), "xx");
1131                         break;
1132                 default:
1133                         /* should not happen, treat like base device */
1134                         snprintf(ua_string, sizeof(ua_string), "%02x",
1135                                  uid.real_unit_addr);
1136                         break;
1137                 }
1138
1139                 if (strlen(uid.vduit) > 0)
1140                         snprintf(uid_string, sizeof(uid_string),
1141                                  "%s.%s.%04x.%s.%s",
1142                                  uid.vendor, uid.serial, uid.ssid, ua_string,
1143                                  uid.vduit);
1144                 else
1145                         snprintf(uid_string, sizeof(uid_string),
1146                                  "%s.%s.%04x.%s",
1147                                  uid.vendor, uid.serial, uid.ssid, ua_string);
1148         }
1149         dasd_put_device(device);
1150
1151         return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
1152 }
1153 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
1154
1155 /*
1156  * extended error-reporting
1157  */
1158 static ssize_t
1159 dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
1160 {
1161         struct dasd_devmap *devmap;
1162         int eer_flag;
1163
1164         devmap = dasd_find_busid(dev_name(dev));
1165         if (!IS_ERR(devmap) && devmap->device)
1166                 eer_flag = dasd_eer_enabled(devmap->device);
1167         else
1168                 eer_flag = 0;
1169         return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
1170 }
1171
1172 static ssize_t
1173 dasd_eer_store(struct device *dev, struct device_attribute *attr,
1174                const char *buf, size_t count)
1175 {
1176         struct dasd_devmap *devmap;
1177         int val, rc;
1178         char *endp;
1179
1180         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1181         if (IS_ERR(devmap))
1182                 return PTR_ERR(devmap);
1183         if (!devmap->device)
1184                 return -ENODEV;
1185
1186         val = simple_strtoul(buf, &endp, 0);
1187         if (((endp + 1) < (buf + count)) || (val > 1))
1188                 return -EINVAL;
1189
1190         if (val) {
1191                 rc = dasd_eer_enable(devmap->device);
1192                 if (rc)
1193                         return rc;
1194         } else
1195                 dasd_eer_disable(devmap->device);
1196         return count;
1197 }
1198
1199 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
1200
1201 /*
1202  * expiration time for default requests
1203  */
1204 static ssize_t
1205 dasd_expires_show(struct device *dev, struct device_attribute *attr, char *buf)
1206 {
1207         struct dasd_device *device;
1208         int len;
1209
1210         device = dasd_device_from_cdev(to_ccwdev(dev));
1211         if (IS_ERR(device))
1212                 return -ENODEV;
1213         len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_expires);
1214         dasd_put_device(device);
1215         return len;
1216 }
1217
1218 static ssize_t
1219 dasd_expires_store(struct device *dev, struct device_attribute *attr,
1220                const char *buf, size_t count)
1221 {
1222         struct dasd_device *device;
1223         unsigned long val;
1224
1225         device = dasd_device_from_cdev(to_ccwdev(dev));
1226         if (IS_ERR(device))
1227                 return -ENODEV;
1228
1229         if ((strict_strtoul(buf, 10, &val) != 0) ||
1230             (val > DASD_EXPIRES_MAX) || val == 0) {
1231                 dasd_put_device(device);
1232                 return -EINVAL;
1233         }
1234
1235         if (val)
1236                 device->default_expires = val;
1237
1238         dasd_put_device(device);
1239         return count;
1240 }
1241
1242 static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store);
1243
1244 static ssize_t dasd_reservation_policy_show(struct device *dev,
1245                                             struct device_attribute *attr,
1246                                             char *buf)
1247 {
1248         struct dasd_devmap *devmap;
1249         int rc = 0;
1250
1251         devmap = dasd_find_busid(dev_name(dev));
1252         if (IS_ERR(devmap)) {
1253                 rc = snprintf(buf, PAGE_SIZE, "ignore\n");
1254         } else {
1255                 spin_lock(&dasd_devmap_lock);
1256                 if (devmap->features & DASD_FEATURE_FAILONSLCK)
1257                         rc = snprintf(buf, PAGE_SIZE, "fail\n");
1258                 else
1259                         rc = snprintf(buf, PAGE_SIZE, "ignore\n");
1260                 spin_unlock(&dasd_devmap_lock);
1261         }
1262         return rc;
1263 }
1264
1265 static ssize_t dasd_reservation_policy_store(struct device *dev,
1266                                              struct device_attribute *attr,
1267                                              const char *buf, size_t count)
1268 {
1269         struct dasd_devmap *devmap;
1270         int rc;
1271
1272         devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
1273         if (IS_ERR(devmap))
1274                 return PTR_ERR(devmap);
1275         rc = 0;
1276         spin_lock(&dasd_devmap_lock);
1277         if (sysfs_streq("ignore", buf))
1278                 devmap->features &= ~DASD_FEATURE_FAILONSLCK;
1279         else if (sysfs_streq("fail", buf))
1280                 devmap->features |= DASD_FEATURE_FAILONSLCK;
1281         else
1282                 rc = -EINVAL;
1283         if (devmap->device)
1284                 devmap->device->features = devmap->features;
1285         spin_unlock(&dasd_devmap_lock);
1286         if (rc)
1287                 return rc;
1288         else
1289                 return count;
1290 }
1291
1292 static DEVICE_ATTR(reservation_policy, 0644,
1293                    dasd_reservation_policy_show, dasd_reservation_policy_store);
1294
1295 static ssize_t dasd_reservation_state_show(struct device *dev,
1296                                            struct device_attribute *attr,
1297                                            char *buf)
1298 {
1299         struct dasd_device *device;
1300         int rc = 0;
1301
1302         device = dasd_device_from_cdev(to_ccwdev(dev));
1303         if (IS_ERR(device))
1304                 return snprintf(buf, PAGE_SIZE, "none\n");
1305
1306         if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags))
1307                 rc = snprintf(buf, PAGE_SIZE, "reserved\n");
1308         else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags))
1309                 rc = snprintf(buf, PAGE_SIZE, "lost\n");
1310         else
1311                 rc = snprintf(buf, PAGE_SIZE, "none\n");
1312         dasd_put_device(device);
1313         return rc;
1314 }
1315
1316 static ssize_t dasd_reservation_state_store(struct device *dev,
1317                                             struct device_attribute *attr,
1318                                             const char *buf, size_t count)
1319 {
1320         struct dasd_device *device;
1321         int rc = 0;
1322
1323         device = dasd_device_from_cdev(to_ccwdev(dev));
1324         if (IS_ERR(device))
1325                 return -ENODEV;
1326         if (sysfs_streq("reset", buf))
1327                 clear_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
1328         else
1329                 rc = -EINVAL;
1330         dasd_put_device(device);
1331
1332         if (rc)
1333                 return rc;
1334         else
1335                 return count;
1336 }
1337
1338 static DEVICE_ATTR(last_known_reservation_state, 0644,
1339                    dasd_reservation_state_show, dasd_reservation_state_store);
1340
1341 static struct attribute * dasd_attrs[] = {
1342         &dev_attr_readonly.attr,
1343         &dev_attr_discipline.attr,
1344         &dev_attr_status.attr,
1345         &dev_attr_alias.attr,
1346         &dev_attr_vendor.attr,
1347         &dev_attr_uid.attr,
1348         &dev_attr_use_diag.attr,
1349         &dev_attr_raw_track_access.attr,
1350         &dev_attr_eer_enabled.attr,
1351         &dev_attr_erplog.attr,
1352         &dev_attr_failfast.attr,
1353         &dev_attr_expires.attr,
1354         &dev_attr_reservation_policy.attr,
1355         &dev_attr_last_known_reservation_state.attr,
1356         &dev_attr_safe_offline.attr,
1357         NULL,
1358 };
1359
1360 static struct attribute_group dasd_attr_group = {
1361         .attrs = dasd_attrs,
1362 };
1363
1364 /*
1365  * Return value of the specified feature.
1366  */
1367 int
1368 dasd_get_feature(struct ccw_device *cdev, int feature)
1369 {
1370         struct dasd_devmap *devmap;
1371
1372         devmap = dasd_find_busid(dev_name(&cdev->dev));
1373         if (IS_ERR(devmap))
1374                 return PTR_ERR(devmap);
1375
1376         return ((devmap->features & feature) != 0);
1377 }
1378
1379 /*
1380  * Set / reset given feature.
1381  * Flag indicates whether to set (!=0) or the reset (=0) the feature.
1382  */
1383 int
1384 dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
1385 {
1386         struct dasd_devmap *devmap;
1387
1388         devmap = dasd_find_busid(dev_name(&cdev->dev));
1389         if (IS_ERR(devmap))
1390                 return PTR_ERR(devmap);
1391
1392         spin_lock(&dasd_devmap_lock);
1393         if (flag)
1394                 devmap->features |= feature;
1395         else
1396                 devmap->features &= ~feature;
1397         if (devmap->device)
1398                 devmap->device->features = devmap->features;
1399         spin_unlock(&dasd_devmap_lock);
1400         return 0;
1401 }
1402
1403
1404 int
1405 dasd_add_sysfs_files(struct ccw_device *cdev)
1406 {
1407         return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
1408 }
1409
1410 void
1411 dasd_remove_sysfs_files(struct ccw_device *cdev)
1412 {
1413         sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
1414 }
1415
1416
1417 int
1418 dasd_devmap_init(void)
1419 {
1420         int i;
1421
1422         /* Initialize devmap structures. */
1423         dasd_max_devindex = 0;
1424         for (i = 0; i < 256; i++)
1425                 INIT_LIST_HEAD(&dasd_hashlists[i]);
1426         return 0;
1427 }
1428
1429 void
1430 dasd_devmap_exit(void)
1431 {
1432         dasd_forget_ranges();
1433 }