git.oblomov.eu Git - linux-2.6/blob - 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 }