git.oblomov.eu Git - linux-2.6/blob - drivers/s390/cio/chsc.c

   1 /*
   2  *  drivers/s390/cio/chsc.c
   3  *   S/390 common I/O routines -- channel subsystem call
   4  *
   5  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
   6  *                            IBM Corporation
   7  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
   8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   9  *               Arnd Bergmann (arndb@de.ibm.com)
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/init.h>
  15 #include <linux/device.h>
  16
  17 #include <asm/cio.h>
  18
  19 #include "css.h"
  20 #include "cio.h"
  21 #include "cio_debug.h"
  22 #include "ioasm.h"
  23 #include "chsc.h"
  24
  25 static void *sei_page;
  26
  27 static int new_channel_path(int chpid);
  28
  29 static inline void
  30 set_chp_logically_online(int chp, int onoff)
  31 {
  32         css[0]->chps[chp]->state = onoff;
  33 }
  34
  35 static int
  36 get_chp_status(int chp)
  37 {
  38         return (css[0]->chps[chp] ? css[0]->chps[chp]->state : -ENODEV);
  39 }
  40
  41 void
  42 chsc_validate_chpids(struct subchannel *sch)
  43 {
  44         int mask, chp;
  45
  46         for (chp = 0; chp <= 7; chp++) {
  47                 mask = 0x80 >> chp;
  48                 if (!get_chp_status(sch->schib.pmcw.chpid[chp]))
  49                         /* disable using this path */
  50                         sch->opm &= ~mask;
  51         }
  52 }
  53
  54 void
  55 chpid_is_actually_online(int chp)
  56 {
  57         int state;
  58
  59         state = get_chp_status(chp);
  60         if (state < 0) {
  61                 need_rescan = 1;
  62                 queue_work(slow_path_wq, &slow_path_work);
  63         } else
  64                 WARN_ON(!state);
  65 }
  66
  67 /* FIXME: this is _always_ called for every subchannel. shouldn't we
  68  *        process more than one at a time? */
  69 static int
  70 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
  71 {
  72         int ccode, j;
  73
  74         struct {
  75                 struct chsc_header request;
  76                 u16 reserved1a:10;
  77                 u16 ssid:2;
  78                 u16 reserved1b:4;
  79                 u16 f_sch;        /* first subchannel */
  80                 u16 reserved2;
  81                 u16 l_sch;        /* last subchannel */
  82                 u32 reserved3;
  83                 struct chsc_header response;
  84                 u32 reserved4;
  85                 u8 sch_valid : 1;
  86                 u8 dev_valid : 1;
  87                 u8 st        : 3; /* subchannel type */
  88                 u8 zeroes    : 3;
  89                 u8  unit_addr;    /* unit address */
  90                 u16 devno;        /* device number */
  91                 u8 path_mask;
  92                 u8 fla_valid_mask;
  93                 u16 sch;          /* subchannel */
  94                 u8 chpid[8];      /* chpids 0-7 */
  95                 u16 fla[8];       /* full link addresses 0-7 */
  96         } __attribute__ ((packed)) *ssd_area;
  97
  98         ssd_area = page;
  99
 100         ssd_area->request.length = 0x0010;
 101         ssd_area->request.code = 0x0004;
 102
 103         ssd_area->ssid = sch->schid.ssid;
 104         ssd_area->f_sch = sch->schid.sch_no;
 105         ssd_area->l_sch = sch->schid.sch_no;
 106
 107         ccode = chsc(ssd_area);
 108         if (ccode > 0) {
 109                 pr_debug("chsc returned with ccode = %d\n", ccode);
 110                 return (ccode == 3) ? -ENODEV : -EBUSY;
 111         }
 112
 113         switch (ssd_area->response.code) {
 114         case 0x0001: /* everything ok */
 115                 break;
 116         case 0x0002:
 117                 CIO_CRW_EVENT(2, "Invalid command!\n");
 118                 return -EINVAL;
 119         case 0x0003:
 120                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
 121                 return -EINVAL;
 122         case 0x0004:
 123                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
 124                 return -EOPNOTSUPP;
 125         default:
 126                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
 127                               ssd_area->response.code);
 128                 return -EIO;
 129         }
 130
 131         /*
 132          * ssd_area->st stores the type of the detected
 133          * subchannel, with the following definitions:
 134          *
 135          * 0: I/O subchannel:     All fields have meaning
 136          * 1: CHSC subchannel:    Only sch_val, st and sch
 137          *                        have meaning
 138          * 2: Message subchannel: All fields except unit_addr
 139          *                        have meaning
 140          * 3: ADM subchannel:     Only sch_val, st and sch
 141          *                        have meaning
 142          *
 143          * Other types are currently undefined.
 144          */
 145         if (ssd_area->st > 3) { /* uhm, that looks strange... */
 146                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
 147                               " for sch 0.%x.%04x\n", ssd_area->st,
 148                               sch->schid.ssid, sch->schid.sch_no);
 149                 /*
 150                  * There may have been a new subchannel type defined in the
 151                  * time since this code was written; since we don't know which
 152                  * fields have meaning and what to do with it we just jump out
 153                  */
 154                 return 0;
 155         } else {
 156                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
 157                 CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
 158                               sch->schid.ssid, sch->schid.sch_no,
 159                               type[ssd_area->st]);
 160
 161                 sch->ssd_info.valid = 1;
 162                 sch->ssd_info.type = ssd_area->st;
 163         }
 164
 165         if (ssd_area->st == 0 || ssd_area->st == 2) {
 166                 for (j = 0; j < 8; j++) {
 167                         if (!((0x80 >> j) & ssd_area->path_mask &
 168                               ssd_area->fla_valid_mask))
 169                                 continue;
 170                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
 171                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
 172                 }
 173         }
 174         return 0;
 175 }
 176
 177 int
 178 css_get_ssd_info(struct subchannel *sch)
 179 {
 180         int ret;
 181         void *page;
 182
 183         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 184         if (!page)
 185                 return -ENOMEM;
 186         spin_lock_irq(sch->lock);
 187         ret = chsc_get_sch_desc_irq(sch, page);
 188         if (ret) {
 189                 static int cio_chsc_err_msg;
 190
 191                 if (!cio_chsc_err_msg) {
 192                         printk(KERN_ERR
 193                                "chsc_get_sch_descriptions:"
 194                                " Error %d while doing chsc; "
 195                                "processing some machine checks may "
 196                                "not work\n", ret);
 197                         cio_chsc_err_msg = 1;
 198                 }
 199         }
 200         spin_unlock_irq(sch->lock);
 201         free_page((unsigned long)page);
 202         if (!ret) {
 203                 int j, chpid, mask;
 204                 /* Allocate channel path structures, if needed. */
 205                 for (j = 0; j < 8; j++) {
 206                         mask = 0x80 >> j;
 207                         chpid = sch->ssd_info.chpid[j];
 208                         if ((sch->schib.pmcw.pim & mask) &&
 209                             (get_chp_status(chpid) < 0))
 210                             new_channel_path(chpid);
 211                 }
 212         }
 213         return ret;
 214 }
 215
 216 static int
 217 s390_subchannel_remove_chpid(struct device *dev, void *data)
 218 {
 219         int j;
 220         int mask;
 221         struct subchannel *sch;
 222         struct channel_path *chpid;
 223         struct schib schib;
 224
 225         sch = to_subchannel(dev);
 226         chpid = data;
 227         for (j = 0; j < 8; j++) {
 228                 mask = 0x80 >> j;
 229                 if ((sch->schib.pmcw.pim & mask) &&
 230                     (sch->schib.pmcw.chpid[j] == chpid->id))
 231                         break;
 232         }
 233         if (j >= 8)
 234                 return 0;
 235
 236         spin_lock_irq(sch->lock);
 237
 238         stsch(sch->schid, &schib);
 239         if (!schib.pmcw.dnv)
 240                 goto out_unreg;
 241         memcpy(&sch->schib, &schib, sizeof(struct schib));
 242         /* Check for single path devices. */
 243         if (sch->schib.pmcw.pim == 0x80)
 244                 goto out_unreg;
 245
 246         if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
 247             (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
 248             (sch->schib.pmcw.lpum == mask)) {
 249                 int cc;
 250
 251                 cc = cio_clear(sch);
 252                 if (cc == -ENODEV)
 253                         goto out_unreg;
 254                 /* Request retry of internal operation. */
 255                 device_set_intretry(sch);
 256                 /* Call handler. */
 257                 if (sch->driver && sch->driver->termination)
 258                         sch->driver->termination(&sch->dev);
 259                 goto out_unlock;
 260         }
 261
 262         /* trigger path verification. */
 263         if (sch->driver && sch->driver->verify)
 264                 sch->driver->verify(&sch->dev);
 265         else if (sch->lpm == mask)
 266                 goto out_unreg;
 267 out_unlock:
 268         spin_unlock_irq(sch->lock);
 269         return 0;
 270 out_unreg:
 271         spin_unlock_irq(sch->lock);
 272         sch->lpm = 0;
 273         if (css_enqueue_subchannel_slow(sch->schid)) {
 274                 css_clear_subchannel_slow_list();
 275                 need_rescan = 1;
 276         }
 277         return 0;
 278 }
 279
 280 static void
 281 s390_set_chpid_offline( __u8 chpid)
 282 {
 283         char dbf_txt[15];
 284         struct device *dev;
 285
 286         sprintf(dbf_txt, "chpr%x", chpid);
 287         CIO_TRACE_EVENT(2, dbf_txt);
 288
 289         if (get_chp_status(chpid) <= 0)
 290                 return;
 291         dev = get_device(&css[0]->chps[chpid]->dev);
 292         bus_for_each_dev(&css_bus_type, NULL, to_channelpath(dev),
 293                          s390_subchannel_remove_chpid);
 294
 295         if (need_rescan || css_slow_subchannels_exist())
 296                 queue_work(slow_path_wq, &slow_path_work);
 297         put_device(dev);
 298 }
 299
 300 struct res_acc_data {
 301         struct channel_path *chp;
 302         u32 fla_mask;
 303         u16 fla;
 304 };
 305
 306 static int
 307 s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
 308 {
 309         int found;
 310         int chp;
 311         int ccode;
 312
 313         found = 0;
 314         for (chp = 0; chp <= 7; chp++)
 315                 /*
 316                  * check if chpid is in information updated by ssd
 317                  */
 318                 if (sch->ssd_info.valid &&
 319                     sch->ssd_info.chpid[chp] == res_data->chp->id &&
 320                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
 321                     == res_data->fla) {
 322                         found = 1;
 323                         break;
 324                 }
 325
 326         if (found == 0)
 327                 return 0;
 328
 329         /*
 330          * Do a stsch to update our subchannel structure with the
 331          * new path information and eventually check for logically
 332          * offline chpids.
 333          */
 334         ccode = stsch(sch->schid, &sch->schib);
 335         if (ccode > 0)
 336                 return 0;
 337
 338         return 0x80 >> chp;
 339 }
 340
 341 static int
 342 s390_process_res_acc_new_sch(struct subchannel_id schid)
 343 {
 344         struct schib schib;
 345         int ret;
 346         /*
 347          * We don't know the device yet, but since a path
 348          * may be available now to the device we'll have
 349          * to do recognition again.
 350          * Since we don't have any idea about which chpid
 351          * that beast may be on we'll have to do a stsch
 352          * on all devices, grr...
 353          */
 354         if (stsch_err(schid, &schib))
 355                 /* We're through */
 356                 return need_rescan ? -EAGAIN : -ENXIO;
 357
 358         /* Put it on the slow path. */
 359         ret = css_enqueue_subchannel_slow(schid);
 360         if (ret) {
 361                 css_clear_subchannel_slow_list();
 362                 need_rescan = 1;
 363                 return -EAGAIN;
 364         }
 365         return 0;
 366 }
 367
 368 static int
 369 __s390_process_res_acc(struct subchannel_id schid, void *data)
 370 {
 371         int chp_mask, old_lpm;
 372         struct res_acc_data *res_data;
 373         struct subchannel *sch;
 374
 375         res_data = data;
 376         sch = get_subchannel_by_schid(schid);
 377         if (!sch)
 378                 /* Check if a subchannel is newly available. */
 379                 return s390_process_res_acc_new_sch(schid);
 380
 381         spin_lock_irq(sch->lock);
 382
 383         chp_mask = s390_process_res_acc_sch(res_data, sch);
 384
 385         if (chp_mask == 0) {
 386                 spin_unlock_irq(sch->lock);
 387                 put_device(&sch->dev);
 388                 return 0;
 389         }
 390         old_lpm = sch->lpm;
 391         sch->lpm = ((sch->schib.pmcw.pim &
 392                      sch->schib.pmcw.pam &
 393                      sch->schib.pmcw.pom)
 394                     | chp_mask) & sch->opm;
 395         if (!old_lpm && sch->lpm)
 396                 device_trigger_reprobe(sch);
 397         else if (sch->driver && sch->driver->verify)
 398                 sch->driver->verify(&sch->dev);
 399
 400         spin_unlock_irq(sch->lock);
 401         put_device(&sch->dev);
 402         return 0;
 403 }
 404
 405
 406 static int
 407 s390_process_res_acc (struct res_acc_data *res_data)
 408 {
 409         int rc;
 410         char dbf_txt[15];
 411
 412         sprintf(dbf_txt, "accpr%x", res_data->chp->id);
 413         CIO_TRACE_EVENT( 2, dbf_txt);
 414         if (res_data->fla != 0) {
 415                 sprintf(dbf_txt, "fla%x", res_data->fla);
 416                 CIO_TRACE_EVENT( 2, dbf_txt);
 417         }
 418
 419         /*
 420          * I/O resources may have become accessible.
 421          * Scan through all subchannels that may be concerned and
 422          * do a validation on those.
 423          * The more information we have (info), the less scanning
 424          * will we have to do.
 425          */
 426         rc = for_each_subchannel(__s390_process_res_acc, res_data);
 427         if (css_slow_subchannels_exist())
 428                 rc = -EAGAIN;
 429         else if (rc != -EAGAIN)
 430                 rc = 0;
 431         return rc;
 432 }
 433
 434 static int
 435 __get_chpid_from_lir(void *data)
 436 {
 437         struct lir {
 438                 u8  iq;
 439                 u8  ic;
 440                 u16 sci;
 441                 /* incident-node descriptor */
 442                 u32 indesc[28];
 443                 /* attached-node descriptor */
 444                 u32 andesc[28];
 445                 /* incident-specific information */
 446                 u32 isinfo[28];
 447         } __attribute__ ((packed)) *lir;
 448
 449         lir = data;
 450         if (!(lir->iq&0x80))
 451                 /* NULL link incident record */
 452                 return -EINVAL;
 453         if (!(lir->indesc[0]&0xc0000000))
 454                 /* node descriptor not valid */
 455                 return -EINVAL;
 456         if (!(lir->indesc[0]&0x10000000))
 457                 /* don't handle device-type nodes - FIXME */
 458                 return -EINVAL;
 459         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
 460
 461         return (u16) (lir->indesc[0]&0x000000ff);
 462 }
 463
 464 struct chsc_sei_area {
 465         struct chsc_header request;
 466         u32 reserved1;
 467         u32 reserved2;
 468         u32 reserved3;
 469         struct chsc_header response;
 470         u32 reserved4;
 471         u8  flags;
 472         u8  vf;         /* validity flags */
 473         u8  rs;         /* reporting source */
 474         u8  cc;         /* content code */
 475         u16 fla;        /* full link address */
 476         u16 rsid;       /* reporting source id */
 477         u32 reserved5;
 478         u32 reserved6;
 479         u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
 480         /* ccdf has to be big enough for a link-incident record */
 481 } __attribute__ ((packed));
 482
 483 static int chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
 484 {
 485         int chpid;
 486
 487         CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
 488                       sei_area->rs, sei_area->rsid);
 489         if (sei_area->rs != 4)
 490                 return 0;
 491         chpid = __get_chpid_from_lir(sei_area->ccdf);
 492         if (chpid < 0)
 493                 CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
 494         else
 495                 s390_set_chpid_offline(chpid);
 496
 497         return 0;
 498 }
 499
 500 static int chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
 501 {
 502         struct res_acc_data res_data;
 503         struct device *dev;
 504         int status;
 505         int rc;
 506
 507         CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
 508                       "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
 509         if (sei_area->rs != 4)
 510                 return 0;
 511         /* allocate a new channel path structure, if needed */
 512         status = get_chp_status(sei_area->rsid);
 513         if (status < 0)
 514                 new_channel_path(sei_area->rsid);
 515         else if (!status)
 516                 return 0;
 517         dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
 518         memset(&res_data, 0, sizeof(struct res_acc_data));
 519         res_data.chp = to_channelpath(dev);
 520         if ((sei_area->vf & 0xc0) != 0) {
 521                 res_data.fla = sei_area->fla;
 522                 if ((sei_area->vf & 0xc0) == 0xc0)
 523                         /* full link address */
 524                         res_data.fla_mask = 0xffff;
 525                 else
 526                         /* link address */
 527                         res_data.fla_mask = 0xff00;
 528         }
 529         rc = s390_process_res_acc(&res_data);
 530         put_device(dev);
 531
 532         return rc;
 533 }
 534
 535 static int chsc_process_sei(struct chsc_sei_area *sei_area)
 536 {
 537         int rc;
 538
 539         /* Check if we might have lost some information. */
 540         if (sei_area->flags & 0x40)
 541                 CIO_CRW_EVENT(2, "chsc: event overflow\n");
 542         /* which kind of information was stored? */
 543         rc = 0;
 544         switch (sei_area->cc) {
 545         case 1: /* link incident*/
 546                 rc = chsc_process_sei_link_incident(sei_area);
 547                 break;
 548         case 2: /* i/o resource accessibiliy */
 549                 rc = chsc_process_sei_res_acc(sei_area);
 550                 break;
 551         default: /* other stuff */
 552                 CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
 553                               sei_area->cc);
 554                 break;
 555         }
 556
 557         return rc;
 558 }
 559
 560 int chsc_process_crw(void)
 561 {
 562         struct chsc_sei_area *sei_area;
 563         int ret;
 564         int rc;
 565
 566         if (!sei_page)
 567                 return 0;
 568         /* Access to sei_page is serialized through machine check handler
 569          * thread, so no need for locking. */
 570         sei_area = sei_page;
 571
 572         CIO_TRACE_EVENT( 2, "prcss");
 573         ret = 0;
 574         do {
 575                 memset(sei_area, 0, sizeof(*sei_area));
 576                 sei_area->request.length = 0x0010;
 577                 sei_area->request.code = 0x000e;
 578                 if (chsc(sei_area))
 579                         break;
 580
 581                 if (sei_area->response.code == 0x0001) {
 582                         CIO_CRW_EVENT(4, "chsc: sei successful\n");
 583                         rc = chsc_process_sei(sei_area);
 584                         if (rc)
 585                                 ret = rc;
 586                 } else {
 587                         CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
 588                                       sei_area->response.code);
 589                         ret = 0;
 590                         break;
 591                 }
 592         } while (sei_area->flags & 0x80);
 593
 594         return ret;
 595 }
 596
 597 static int
 598 __chp_add_new_sch(struct subchannel_id schid)
 599 {
 600         struct schib schib;
 601         int ret;
 602
 603         if (stsch_err(schid, &schib))
 604                 /* We're through */
 605                 return need_rescan ? -EAGAIN : -ENXIO;
 606
 607         /* Put it on the slow path. */
 608         ret = css_enqueue_subchannel_slow(schid);
 609         if (ret) {
 610                 css_clear_subchannel_slow_list();
 611                 need_rescan = 1;
 612                 return -EAGAIN;
 613         }
 614         return 0;
 615 }
 616
 617
 618 static int
 619 __chp_add(struct subchannel_id schid, void *data)
 620 {
 621         int i, mask;
 622         struct channel_path *chp;
 623         struct subchannel *sch;
 624
 625         chp = data;
 626         sch = get_subchannel_by_schid(schid);
 627         if (!sch)
 628                 /* Check if the subchannel is now available. */
 629                 return __chp_add_new_sch(schid);
 630         spin_lock_irq(sch->lock);
 631         for (i=0; i<8; i++) {
 632                 mask = 0x80 >> i;
 633                 if ((sch->schib.pmcw.pim & mask) &&
 634                     (sch->schib.pmcw.chpid[i] == chp->id)) {
 635                         if (stsch(sch->schid, &sch->schib) != 0) {
 636                                 /* Endgame. */
 637                                 spin_unlock_irq(sch->lock);
 638                                 return -ENXIO;
 639                         }
 640                         break;
 641                 }
 642         }
 643         if (i==8) {
 644                 spin_unlock_irq(sch->lock);
 645                 return 0;
 646         }
 647         sch->lpm = ((sch->schib.pmcw.pim &
 648                      sch->schib.pmcw.pam &
 649                      sch->schib.pmcw.pom)
 650                     | mask) & sch->opm;
 651
 652         if (sch->driver && sch->driver->verify)
 653                 sch->driver->verify(&sch->dev);
 654
 655         spin_unlock_irq(sch->lock);
 656         put_device(&sch->dev);
 657         return 0;
 658 }
 659
 660 static int
 661 chp_add(int chpid)
 662 {
 663         int rc;
 664         char dbf_txt[15];
 665         struct device *dev;
 666
 667         if (!get_chp_status(chpid))
 668                 return 0; /* no need to do the rest */
 669
 670         sprintf(dbf_txt, "cadd%x", chpid);
 671         CIO_TRACE_EVENT(2, dbf_txt);
 672
 673         dev = get_device(&css[0]->chps[chpid]->dev);
 674         rc = for_each_subchannel(__chp_add, to_channelpath(dev));
 675         if (css_slow_subchannels_exist())
 676                 rc = -EAGAIN;
 677         if (rc != -EAGAIN)
 678                 rc = 0;
 679         put_device(dev);
 680         return rc;
 681 }
 682
 683 /*
 684  * Handling of crw machine checks with channel path source.
 685  */
 686 int
 687 chp_process_crw(int chpid, int on)
 688 {
 689         if (on == 0) {
 690                 /* Path has gone. We use the link incident routine.*/
 691                 s390_set_chpid_offline(chpid);
 692                 return 0; /* De-register is async anyway. */
 693         }
 694         /*
 695          * Path has come. Allocate a new channel path structure,
 696          * if needed.
 697          */
 698         if (get_chp_status(chpid) < 0)
 699                 new_channel_path(chpid);
 700         /* Avoid the extra overhead in process_rec_acc. */
 701         return chp_add(chpid);
 702 }
 703
 704 static int check_for_io_on_path(struct subchannel *sch, int index)
 705 {
 706         int cc;
 707
 708         cc = stsch(sch->schid, &sch->schib);
 709         if (cc)
 710                 return 0;
 711         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index))
 712                 return 1;
 713         return 0;
 714 }
 715
 716 static void terminate_internal_io(struct subchannel *sch)
 717 {
 718         if (cio_clear(sch)) {
 719                 /* Recheck device in case clear failed. */
 720                 sch->lpm = 0;
 721                 if (device_trigger_verify(sch) != 0) {
 722                         if(css_enqueue_subchannel_slow(sch->schid)) {
 723                                 css_clear_subchannel_slow_list();
 724                                 need_rescan = 1;
 725                         }
 726                 }
 727                 return;
 728         }
 729         /* Request retry of internal operation. */
 730         device_set_intretry(sch);
 731         /* Call handler. */
 732         if (sch->driver && sch->driver->termination)
 733                 sch->driver->termination(&sch->dev);
 734 }
 735
 736 static void
 737 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
 738 {
 739         int chp, old_lpm;
 740         unsigned long flags;
 741
 742         if (!sch->ssd_info.valid)
 743                 return;
 744
 745         spin_lock_irqsave(sch->lock, flags);
 746         old_lpm = sch->lpm;
 747         for (chp = 0; chp < 8; chp++) {
 748                 if (sch->ssd_info.chpid[chp] != chpid)
 749                         continue;
 750
 751                 if (on) {
 752                         sch->opm |= (0x80 >> chp);
 753                         sch->lpm |= (0x80 >> chp);
 754                         if (!old_lpm)
 755                                 device_trigger_reprobe(sch);
 756                         else if (sch->driver && sch->driver->verify)
 757                                 sch->driver->verify(&sch->dev);
 758                         break;
 759                 }
 760                 sch->opm &= ~(0x80 >> chp);
 761                 sch->lpm &= ~(0x80 >> chp);
 762                 if (check_for_io_on_path(sch, chp)) {
 763                         if (device_is_online(sch))
 764                                 /* Path verification is done after killing. */
 765                                 device_kill_io(sch);
 766                         else
 767                                 /* Kill and retry internal I/O. */
 768                                 terminate_internal_io(sch);
 769                 } else if (!sch->lpm) {
 770                         if (device_trigger_verify(sch) != 0) {
 771                                 if (css_enqueue_subchannel_slow(sch->schid)) {
 772                                         css_clear_subchannel_slow_list();
 773                                         need_rescan = 1;
 774                                 }
 775                         }
 776                 } else if (sch->driver && sch->driver->verify)
 777                         sch->driver->verify(&sch->dev);
 778                 break;
 779         }
 780         spin_unlock_irqrestore(sch->lock, flags);
 781 }
 782
 783 static int
 784 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
 785 {
 786         struct subchannel *sch;
 787         __u8 *chpid;
 788
 789         sch = to_subchannel(dev);
 790         chpid = data;
 791
 792         __s390_subchannel_vary_chpid(sch, *chpid, 0);
 793         return 0;
 794 }
 795
 796 static int
 797 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
 798 {
 799         struct subchannel *sch;
 800         __u8 *chpid;
 801
 802         sch = to_subchannel(dev);
 803         chpid = data;
 804
 805         __s390_subchannel_vary_chpid(sch, *chpid, 1);
 806         return 0;
 807 }
 808
 809 static int
 810 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
 811 {
 812         struct schib schib;
 813         struct subchannel *sch;
 814
 815         sch = get_subchannel_by_schid(schid);
 816         if (sch) {
 817                 put_device(&sch->dev);
 818                 return 0;
 819         }
 820         if (stsch_err(schid, &schib))
 821                 /* We're through */
 822                 return -ENXIO;
 823         /* Put it on the slow path. */
 824         if (css_enqueue_subchannel_slow(schid)) {
 825                 css_clear_subchannel_slow_list();
 826                 need_rescan = 1;
 827                 return -EAGAIN;
 828         }
 829         return 0;
 830 }
 831
 832 /*
 833  * Function: s390_vary_chpid
 834  * Varies the specified chpid online or offline
 835  */
 836 static int
 837 s390_vary_chpid( __u8 chpid, int on)
 838 {
 839         char dbf_text[15];
 840         int status;
 841
 842         sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
 843         CIO_TRACE_EVENT( 2, dbf_text);
 844
 845         status = get_chp_status(chpid);
 846         if (status < 0) {
 847                 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
 848                 return -EINVAL;
 849         }
 850
 851         if (!on && !status) {
 852                 printk(KERN_ERR "chpid %x is already offline\n", chpid);
 853                 return -EINVAL;
 854         }
 855
 856         set_chp_logically_online(chpid, on);
 857
 858         /*
 859          * Redo PathVerification on the devices the chpid connects to
 860          */
 861
 862         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
 863                          s390_subchannel_vary_chpid_on :
 864                          s390_subchannel_vary_chpid_off);
 865         if (on)
 866                 /* Scan for new devices on varied on path. */
 867                 for_each_subchannel(__s390_vary_chpid_on, NULL);
 868         if (need_rescan || css_slow_subchannels_exist())
 869                 queue_work(slow_path_wq, &slow_path_work);
 870         return 0;
 871 }
 872
 873 /*
 874  * Channel measurement related functions
 875  */
 876 static ssize_t
 877 chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
 878                            size_t count)
 879 {
 880         struct channel_path *chp;
 881         unsigned int size;
 882
 883         chp = to_channelpath(container_of(kobj, struct device, kobj));
 884         if (!chp->cmg_chars)
 885                 return 0;
 886
 887         size = sizeof(struct cmg_chars);
 888
 889         if (off > size)
 890                 return 0;
 891         if (off + count > size)
 892                 count = size - off;
 893         memcpy(buf, chp->cmg_chars + off, count);
 894         return count;
 895 }
 896
 897 static struct bin_attribute chp_measurement_chars_attr = {
 898         .attr = {
 899                 .name = "measurement_chars",
 900                 .mode = S_IRUSR,
 901                 .owner = THIS_MODULE,
 902         },
 903         .size = sizeof(struct cmg_chars),
 904         .read = chp_measurement_chars_read,
 905 };
 906
 907 static void
 908 chp_measurement_copy_block(struct cmg_entry *buf,
 909                            struct channel_subsystem *css, int chpid)
 910 {
 911         void *area;
 912         struct cmg_entry *entry, reference_buf;
 913         int idx;
 914
 915         if (chpid < 128) {
 916                 area = css->cub_addr1;
 917                 idx = chpid;
 918         } else {
 919                 area = css->cub_addr2;
 920                 idx = chpid - 128;
 921         }
 922         entry = area + (idx * sizeof(struct cmg_entry));
 923         do {
 924                 memcpy(buf, entry, sizeof(*entry));
 925                 memcpy(&reference_buf, entry, sizeof(*entry));
 926         } while (reference_buf.values[0] != buf->values[0]);
 927 }
 928
 929 static ssize_t
 930 chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
 931 {
 932         struct channel_path *chp;
 933         struct channel_subsystem *css;
 934         unsigned int size;
 935
 936         chp = to_channelpath(container_of(kobj, struct device, kobj));
 937         css = to_css(chp->dev.parent);
 938
 939         size = sizeof(struct cmg_entry);
 940
 941         /* Only allow single reads. */
 942         if (off || count < size)
 943                 return 0;
 944         chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
 945         count = size;
 946         return count;
 947 }
 948
 949 static struct bin_attribute chp_measurement_attr = {
 950         .attr = {
 951                 .name = "measurement",
 952                 .mode = S_IRUSR,
 953                 .owner = THIS_MODULE,
 954         },
 955         .size = sizeof(struct cmg_entry),
 956         .read = chp_measurement_read,
 957 };
 958
 959 static void
 960 chsc_remove_chp_cmg_attr(struct channel_path *chp)
 961 {
 962         device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
 963         device_remove_bin_file(&chp->dev, &chp_measurement_attr);
 964 }
 965
 966 static int
 967 chsc_add_chp_cmg_attr(struct channel_path *chp)
 968 {
 969         int ret;
 970
 971         ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
 972         if (ret)
 973                 return ret;
 974         ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
 975         if (ret)
 976                 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
 977         return ret;
 978 }
 979
 980 static void
 981 chsc_remove_cmg_attr(struct channel_subsystem *css)
 982 {
 983         int i;
 984
 985         for (i = 0; i <= __MAX_CHPID; i++) {
 986                 if (!css->chps[i])
 987                         continue;
 988                 chsc_remove_chp_cmg_attr(css->chps[i]);
 989         }
 990 }
 991
 992 static int
 993 chsc_add_cmg_attr(struct channel_subsystem *css)
 994 {
 995         int i, ret;
 996
 997         ret = 0;
 998         for (i = 0; i <= __MAX_CHPID; i++) {
 999                 if (!css->chps[i])
1000                         continue;
1001                 ret = chsc_add_chp_cmg_attr(css->chps[i]);
1002                 if (ret)
1003                         goto cleanup;
1004         }
1005         return ret;
1006 cleanup:
1007         for (--i; i >= 0; i--) {
1008                 if (!css->chps[i])
1009                         continue;
1010                 chsc_remove_chp_cmg_attr(css->chps[i]);
1011         }
1012         return ret;
1013 }
1014
1015
1016 static int
1017 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
1018 {
1019         struct {
1020                 struct chsc_header request;
1021                 u32 operation_code : 2;
1022                 u32 : 30;
1023                 u32 key : 4;
1024                 u32 : 28;
1025                 u32 zeroes1;
1026                 u32 cub_addr1;
1027                 u32 zeroes2;
1028                 u32 cub_addr2;
1029                 u32 reserved[13];
1030                 struct chsc_header response;
1031                 u32 status : 8;
1032                 u32 : 4;
1033                 u32 fmt : 4;
1034                 u32 : 16;
1035         } __attribute__ ((packed)) *secm_area;
1036         int ret, ccode;
1037
1038         secm_area = page;
1039         secm_area->request.length = 0x0050;
1040         secm_area->request.code = 0x0016;
1041
1042         secm_area->key = PAGE_DEFAULT_KEY;
1043         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
1044         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
1045
1046         secm_area->operation_code = enable ? 0 : 1;
1047
1048         ccode = chsc(secm_area);
1049         if (ccode > 0)
1050                 return (ccode == 3) ? -ENODEV : -EBUSY;
1051
1052         switch (secm_area->response.code) {
1053         case 0x0001: /* Success. */
1054                 ret = 0;
1055                 break;
1056         case 0x0003: /* Invalid block. */
1057         case 0x0007: /* Invalid format. */
1058         case 0x0008: /* Other invalid block. */
1059                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1060                 ret = -EINVAL;
1061                 break;
1062         case 0x0004: /* Command not provided in model. */
1063                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
1064                 ret = -EOPNOTSUPP;
1065                 break;
1066         case 0x0102: /* cub adresses incorrect */
1067                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
1068                 ret = -EINVAL;
1069                 break;
1070         case 0x0103: /* key error */
1071                 CIO_CRW_EVENT(2, "Access key error in secm\n");
1072                 ret = -EINVAL;
1073                 break;
1074         case 0x0105: /* error while starting */
1075                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
1076                 ret = -EIO;
1077                 break;
1078         default:
1079                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1080                               secm_area->response.code);
1081                 ret = -EIO;
1082         }
1083         return ret;
1084 }
1085
1086 int
1087 chsc_secm(struct channel_subsystem *css, int enable)
1088 {
1089         void  *secm_area;
1090         int ret;
1091
1092         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
1093         if (!secm_area)
1094                 return -ENOMEM;
1095
1096         mutex_lock(&css->mutex);
1097         if (enable && !css->cm_enabled) {
1098                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1099                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1100                 if (!css->cub_addr1 || !css->cub_addr2) {
1101                         free_page((unsigned long)css->cub_addr1);
1102                         free_page((unsigned long)css->cub_addr2);
1103                         free_page((unsigned long)secm_area);
1104                         mutex_unlock(&css->mutex);
1105                         return -ENOMEM;
1106                 }
1107         }
1108         ret = __chsc_do_secm(css, enable, secm_area);
1109         if (!ret) {
1110                 css->cm_enabled = enable;
1111                 if (css->cm_enabled) {
1112                         ret = chsc_add_cmg_attr(css);
1113                         if (ret) {
1114                                 memset(secm_area, 0, PAGE_SIZE);
1115                                 __chsc_do_secm(css, 0, secm_area);
1116                                 css->cm_enabled = 0;
1117                         }
1118                 } else
1119                         chsc_remove_cmg_attr(css);
1120         }
1121         if (enable && !css->cm_enabled) {
1122                 free_page((unsigned long)css->cub_addr1);
1123                 free_page((unsigned long)css->cub_addr2);
1124         }
1125         mutex_unlock(&css->mutex);
1126         free_page((unsigned long)secm_area);
1127         return ret;
1128 }
1129
1130 /*
1131  * Files for the channel path entries.
1132  */
1133 static ssize_t
1134 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
1135 {
1136         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1137
1138         if (!chp)
1139                 return 0;
1140         return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
1141                 sprintf(buf, "offline\n"));
1142 }
1143
1144 static ssize_t
1145 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
1146 {
1147         struct channel_path *cp = container_of(dev, struct channel_path, dev);
1148         char cmd[10];
1149         int num_args;
1150         int error;
1151
1152         num_args = sscanf(buf, "%5s", cmd);
1153         if (!num_args)
1154                 return count;
1155
1156         if (!strnicmp(cmd, "on", 2))
1157                 error = s390_vary_chpid(cp->id, 1);
1158         else if (!strnicmp(cmd, "off", 3))
1159                 error = s390_vary_chpid(cp->id, 0);
1160         else
1161                 error = -EINVAL;
1162
1163         return error < 0 ? error : count;
1164
1165 }
1166
1167 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
1168
1169 static ssize_t
1170 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
1171 {
1172         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1173
1174         if (!chp)
1175                 return 0;
1176         return sprintf(buf, "%x\n", chp->desc.desc);
1177 }
1178
1179 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
1180
1181 static ssize_t
1182 chp_cmg_show(struct device *dev, struct device_attribute *attr, char *buf)
1183 {
1184         struct channel_path *chp = to_channelpath(dev);
1185
1186         if (!chp)
1187                 return 0;
1188         if (chp->cmg == -1) /* channel measurements not available */
1189                 return sprintf(buf, "unknown\n");
1190         return sprintf(buf, "%x\n", chp->cmg);
1191 }
1192
1193 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
1194
1195 static ssize_t
1196 chp_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
1197 {
1198         struct channel_path *chp = to_channelpath(dev);
1199
1200         if (!chp)
1201                 return 0;
1202         if (chp->shared == -1) /* channel measurements not available */
1203                 return sprintf(buf, "unknown\n");
1204         return sprintf(buf, "%x\n", chp->shared);
1205 }
1206
1207 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
1208
1209 static struct attribute * chp_attrs[] = {
1210         &dev_attr_status.attr,
1211         &dev_attr_type.attr,
1212         &dev_attr_cmg.attr,
1213         &dev_attr_shared.attr,
1214         NULL,
1215 };
1216
1217 static struct attribute_group chp_attr_group = {
1218         .attrs = chp_attrs,
1219 };
1220
1221 static void
1222 chp_release(struct device *dev)
1223 {
1224         struct channel_path *cp;
1225
1226         cp = container_of(dev, struct channel_path, dev);
1227         kfree(cp);
1228 }
1229
1230 static int
1231 chsc_determine_channel_path_description(int chpid,
1232                                         struct channel_path_desc *desc)
1233 {
1234         int ccode, ret;
1235
1236         struct {
1237                 struct chsc_header request;
1238                 u32 : 24;
1239                 u32 first_chpid : 8;
1240                 u32 : 24;
1241                 u32 last_chpid : 8;
1242                 u32 zeroes1;
1243                 struct chsc_header response;
1244                 u32 zeroes2;
1245                 struct channel_path_desc desc;
1246         } __attribute__ ((packed)) *scpd_area;
1247
1248         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1249         if (!scpd_area)
1250                 return -ENOMEM;
1251
1252         scpd_area->request.length = 0x0010;
1253         scpd_area->request.code = 0x0002;
1254
1255         scpd_area->first_chpid = chpid;
1256         scpd_area->last_chpid = chpid;
1257
1258         ccode = chsc(scpd_area);
1259         if (ccode > 0) {
1260                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1261                 goto out;
1262         }
1263
1264         switch (scpd_area->response.code) {
1265         case 0x0001: /* Success. */
1266                 memcpy(desc, &scpd_area->desc,
1267                        sizeof(struct channel_path_desc));
1268                 ret = 0;
1269                 break;
1270         case 0x0003: /* Invalid block. */
1271         case 0x0007: /* Invalid format. */
1272         case 0x0008: /* Other invalid block. */
1273                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1274                 ret = -EINVAL;
1275                 break;
1276         case 0x0004: /* Command not provided in model. */
1277                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
1278                 ret = -EOPNOTSUPP;
1279                 break;
1280         default:
1281                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1282                               scpd_area->response.code);
1283                 ret = -EIO;
1284         }
1285 out:
1286         free_page((unsigned long)scpd_area);
1287         return ret;
1288 }
1289
1290 static void
1291 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1292                           struct cmg_chars *chars)
1293 {
1294         switch (chp->cmg) {
1295         case 2:
1296         case 3:
1297                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1298                                          GFP_KERNEL);
1299                 if (chp->cmg_chars) {
1300                         int i, mask;
1301                         struct cmg_chars *cmg_chars;
1302
1303                         cmg_chars = chp->cmg_chars;
1304                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1305                                 mask = 0x80 >> (i + 3);
1306                                 if (cmcv & mask)
1307                                         cmg_chars->values[i] = chars->values[i];
1308                                 else
1309                                         cmg_chars->values[i] = 0;
1310                         }
1311                 }
1312                 break;
1313         default:
1314                 /* No cmg-dependent data. */
1315                 break;
1316         }
1317 }
1318
1319 static int
1320 chsc_get_channel_measurement_chars(struct channel_path *chp)
1321 {
1322         int ccode, ret;
1323
1324         struct {
1325                 struct chsc_header request;
1326                 u32 : 24;
1327                 u32 first_chpid : 8;
1328                 u32 : 24;
1329                 u32 last_chpid : 8;
1330                 u32 zeroes1;
1331                 struct chsc_header response;
1332                 u32 zeroes2;
1333                 u32 not_valid : 1;
1334                 u32 shared : 1;
1335                 u32 : 22;
1336                 u32 chpid : 8;
1337                 u32 cmcv : 5;
1338                 u32 : 11;
1339                 u32 cmgq : 8;
1340                 u32 cmg : 8;
1341                 u32 zeroes3;
1342                 u32 data[NR_MEASUREMENT_CHARS];
1343         } __attribute__ ((packed)) *scmc_area;
1344
1345         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1346         if (!scmc_area)
1347                 return -ENOMEM;
1348
1349         scmc_area->request.length = 0x0010;
1350         scmc_area->request.code = 0x0022;
1351
1352         scmc_area->first_chpid = chp->id;
1353         scmc_area->last_chpid = chp->id;
1354
1355         ccode = chsc(scmc_area);
1356         if (ccode > 0) {
1357                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1358                 goto out;
1359         }
1360
1361         switch (scmc_area->response.code) {
1362         case 0x0001: /* Success. */
1363                 if (!scmc_area->not_valid) {
1364                         chp->cmg = scmc_area->cmg;
1365                         chp->shared = scmc_area->shared;
1366                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1367                                                   (struct cmg_chars *)
1368                                                   &scmc_area->data);
1369                 } else {
1370                         chp->cmg = -1;
1371                         chp->shared = -1;
1372                 }
1373                 ret = 0;
1374                 break;
1375         case 0x0003: /* Invalid block. */
1376         case 0x0007: /* Invalid format. */
1377         case 0x0008: /* Invalid bit combination. */
1378                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1379                 ret = -EINVAL;
1380                 break;
1381         case 0x0004: /* Command not provided. */
1382                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1383                 ret = -EOPNOTSUPP;
1384                 break;
1385         default:
1386                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1387                               scmc_area->response.code);
1388                 ret = -EIO;
1389         }
1390 out:
1391         free_page((unsigned long)scmc_area);
1392         return ret;
1393 }
1394
1395 /*
1396  * Entries for chpids on the system bus.
1397  * This replaces /proc/chpids.
1398  */
1399 static int
1400 new_channel_path(int chpid)
1401 {
1402         struct channel_path *chp;
1403         int ret;
1404
1405         chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
1406         if (!chp)
1407                 return -ENOMEM;
1408
1409         /* fill in status, etc. */
1410         chp->id = chpid;
1411         chp->state = 1;
1412         chp->dev.parent = &css[0]->device;
1413         chp->dev.release = chp_release;
1414         snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1415
1416         /* Obtain channel path description and fill it in. */
1417         ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1418         if (ret)
1419                 goto out_free;
1420         /* Get channel-measurement characteristics. */
1421         if (css_characteristics_avail && css_chsc_characteristics.scmc
1422             && css_chsc_characteristics.secm) {
1423                 ret = chsc_get_channel_measurement_chars(chp);
1424                 if (ret)
1425                         goto out_free;
1426         } else {
1427                 static int msg_done;
1428
1429                 if (!msg_done) {
1430                         printk(KERN_WARNING "cio: Channel measurements not "
1431                                "available, continuing.\n");
1432                         msg_done = 1;
1433                 }
1434                 chp->cmg = -1;
1435         }
1436
1437         /* make it known to the system */
1438         ret = device_register(&chp->dev);
1439         if (ret) {
1440                 printk(KERN_WARNING "%s: could not register %02x\n",
1441                        __func__, chpid);
1442                 goto out_free;
1443         }
1444         ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1445         if (ret) {
1446                 device_unregister(&chp->dev);
1447                 goto out_free;
1448         }
1449         mutex_lock(&css[0]->mutex);
1450         if (css[0]->cm_enabled) {
1451                 ret = chsc_add_chp_cmg_attr(chp);
1452                 if (ret) {
1453                         sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
1454                         device_unregister(&chp->dev);
1455                         mutex_unlock(&css[0]->mutex);
1456                         goto out_free;
1457                 }
1458         }
1459         css[0]->chps[chpid] = chp;
1460         mutex_unlock(&css[0]->mutex);
1461         return ret;
1462 out_free:
1463         kfree(chp);
1464         return ret;
1465 }
1466
1467 void *
1468 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1469 {
1470         struct channel_path *chp;
1471         struct channel_path_desc *desc;
1472
1473         chp = css[0]->chps[sch->schib.pmcw.chpid[chp_no]];
1474         if (!chp)
1475                 return NULL;
1476         desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1477         if (!desc)
1478                 return NULL;
1479         memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1480         return desc;
1481 }
1482
1483 static int __init
1484 chsc_alloc_sei_area(void)
1485 {
1486         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1487         if (!sei_page)
1488                 printk(KERN_WARNING"Can't allocate page for processing of " \
1489                        "chsc machine checks!\n");
1490         return (sei_page ? 0 : -ENOMEM);
1491 }
1492
1493 int __init
1494 chsc_enable_facility(int operation_code)
1495 {
1496         int ret;
1497         struct {
1498                 struct chsc_header request;
1499                 u8 reserved1:4;
1500                 u8 format:4;
1501                 u8 reserved2;
1502                 u16 operation_code;
1503                 u32 reserved3;
1504                 u32 reserved4;
1505                 u32 operation_data_area[252];
1506                 struct chsc_header response;
1507                 u32 reserved5:4;
1508                 u32 format2:4;
1509                 u32 reserved6:24;
1510         } __attribute__ ((packed)) *sda_area;
1511
1512         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1513         if (!sda_area)
1514                 return -ENOMEM;
1515         sda_area->request.length = 0x0400;
1516         sda_area->request.code = 0x0031;
1517         sda_area->operation_code = operation_code;
1518
1519         ret = chsc(sda_area);
1520         if (ret > 0) {
1521                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1522                 goto out;
1523         }
1524         switch (sda_area->response.code) {
1525         case 0x0001: /* everything ok */
1526                 ret = 0;
1527                 break;
1528         case 0x0003: /* invalid request block */
1529         case 0x0007:
1530                 ret = -EINVAL;
1531                 break;
1532         case 0x0004: /* command not provided */
1533         case 0x0101: /* facility not provided */
1534                 ret = -EOPNOTSUPP;
1535                 break;
1536         default: /* something went wrong */
1537                 ret = -EIO;
1538         }
1539  out:
1540         free_page((unsigned long)sda_area);
1541         return ret;
1542 }
1543
1544 subsys_initcall(chsc_alloc_sei_area);
1545
1546 struct css_general_char css_general_characteristics;
1547 struct css_chsc_char css_chsc_characteristics;
1548
1549 int __init
1550 chsc_determine_css_characteristics(void)
1551 {
1552         int result;
1553         struct {
1554                 struct chsc_header request;
1555                 u32 reserved1;
1556                 u32 reserved2;
1557                 u32 reserved3;
1558                 struct chsc_header response;
1559                 u32 reserved4;
1560                 u32 general_char[510];
1561                 u32 chsc_char[518];
1562         } __attribute__ ((packed)) *scsc_area;
1563
1564         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1565         if (!scsc_area) {
1566                 printk(KERN_WARNING"cio: Was not able to determine available" \
1567                        "CHSCs due to no memory.\n");
1568                 return -ENOMEM;
1569         }
1570
1571         scsc_area->request.length = 0x0010;
1572         scsc_area->request.code = 0x0010;
1573
1574         result = chsc(scsc_area);
1575         if (result) {
1576                 printk(KERN_WARNING"cio: Was not able to determine " \
1577                        "available CHSCs, cc=%i.\n", result);
1578                 result = -EIO;
1579                 goto exit;
1580         }
1581
1582         if (scsc_area->response.code != 1) {
1583                 printk(KERN_WARNING"cio: Was not able to determine " \
1584                        "available CHSCs.\n");
1585                 result = -EIO;
1586                 goto exit;
1587         }
1588         memcpy(&css_general_characteristics, scsc_area->general_char,
1589                sizeof(css_general_characteristics));
1590         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1591                sizeof(css_chsc_characteristics));
1592 exit:
1593         free_page ((unsigned long) scsc_area);
1594         return result;
1595 }
1596
1597 EXPORT_SYMBOL_GPL(css_general_characteristics);
1598 EXPORT_SYMBOL_GPL(css_chsc_characteristics);