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         } *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;
 204                 /* Allocate channel path structures, if needed. */
 205                 for (j = 0; j < 8; j++) {
 206                         chpid = sch->ssd_info.chpid[j];
 207                         if (chpid && (get_chp_status(chpid) < 0))
 208                             new_channel_path(chpid);
 209                 }
 210         }
 211         return ret;
 212 }
 213
 214 static int
 215 s390_subchannel_remove_chpid(struct device *dev, void *data)
 216 {
 217         int j;
 218         int mask;
 219         struct subchannel *sch;
 220         struct channel_path *chpid;
 221         struct schib schib;
 222
 223         sch = to_subchannel(dev);
 224         chpid = data;
 225         for (j = 0; j < 8; j++)
 226                 if (sch->schib.pmcw.chpid[j] == chpid->id)
 227                         break;
 228         if (j >= 8)
 229                 return 0;
 230
 231         mask = 0x80 >> j;
 232         spin_lock_irq(&sch->lock);
 233
 234         stsch(sch->schid, &schib);
 235         if (!schib.pmcw.dnv)
 236                 goto out_unreg;
 237         memcpy(&sch->schib, &schib, sizeof(struct schib));
 238         /* Check for single path devices. */
 239         if (sch->schib.pmcw.pim == 0x80)
 240                 goto out_unreg;
 241
 242         if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
 243             (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
 244             (sch->schib.pmcw.lpum == mask)) {
 245                 int cc;
 246
 247                 cc = cio_clear(sch);
 248                 if (cc == -ENODEV)
 249                         goto out_unreg;
 250                 /* Call handler. */
 251                 if (sch->driver && sch->driver->termination)
 252                         sch->driver->termination(&sch->dev);
 253                 goto out_unlock;
 254         }
 255
 256         /* trigger path verification. */
 257         if (sch->driver && sch->driver->verify)
 258                 sch->driver->verify(&sch->dev);
 259         else if (sch->lpm == mask)
 260                 goto out_unreg;
 261 out_unlock:
 262         spin_unlock_irq(&sch->lock);
 263         return 0;
 264 out_unreg:
 265         spin_unlock_irq(&sch->lock);
 266         sch->lpm = 0;
 267         if (css_enqueue_subchannel_slow(sch->schid)) {
 268                 css_clear_subchannel_slow_list();
 269                 need_rescan = 1;
 270         }
 271         return 0;
 272 }
 273
 274 static inline void
 275 s390_set_chpid_offline( __u8 chpid)
 276 {
 277         char dbf_txt[15];
 278         struct device *dev;
 279
 280         sprintf(dbf_txt, "chpr%x", chpid);
 281         CIO_TRACE_EVENT(2, dbf_txt);
 282
 283         if (get_chp_status(chpid) <= 0)
 284                 return;
 285         dev = get_device(&css[0]->chps[chpid]->dev);
 286         bus_for_each_dev(&css_bus_type, NULL, to_channelpath(dev),
 287                          s390_subchannel_remove_chpid);
 288
 289         if (need_rescan || css_slow_subchannels_exist())
 290                 queue_work(slow_path_wq, &slow_path_work);
 291         put_device(dev);
 292 }
 293
 294 struct res_acc_data {
 295         struct channel_path *chp;
 296         u32 fla_mask;
 297         u16 fla;
 298 };
 299
 300 static int
 301 s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
 302 {
 303         int found;
 304         int chp;
 305         int ccode;
 306
 307         found = 0;
 308         for (chp = 0; chp <= 7; chp++)
 309                 /*
 310                  * check if chpid is in information updated by ssd
 311                  */
 312                 if (sch->ssd_info.valid &&
 313                     sch->ssd_info.chpid[chp] == res_data->chp->id &&
 314                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
 315                     == res_data->fla) {
 316                         found = 1;
 317                         break;
 318                 }
 319
 320         if (found == 0)
 321                 return 0;
 322
 323         /*
 324          * Do a stsch to update our subchannel structure with the
 325          * new path information and eventually check for logically
 326          * offline chpids.
 327          */
 328         ccode = stsch(sch->schid, &sch->schib);
 329         if (ccode > 0)
 330                 return 0;
 331
 332         return 0x80 >> chp;
 333 }
 334
 335 static inline int
 336 s390_process_res_acc_new_sch(struct subchannel_id schid)
 337 {
 338         struct schib schib;
 339         int ret;
 340         /*
 341          * We don't know the device yet, but since a path
 342          * may be available now to the device we'll have
 343          * to do recognition again.
 344          * Since we don't have any idea about which chpid
 345          * that beast may be on we'll have to do a stsch
 346          * on all devices, grr...
 347          */
 348         if (stsch_err(schid, &schib))
 349                 /* We're through */
 350                 return need_rescan ? -EAGAIN : -ENXIO;
 351
 352         /* Put it on the slow path. */
 353         ret = css_enqueue_subchannel_slow(schid);
 354         if (ret) {
 355                 css_clear_subchannel_slow_list();
 356                 need_rescan = 1;
 357                 return -EAGAIN;
 358         }
 359         return 0;
 360 }
 361
 362 static int
 363 __s390_process_res_acc(struct subchannel_id schid, void *data)
 364 {
 365         int chp_mask, old_lpm;
 366         struct res_acc_data *res_data;
 367         struct subchannel *sch;
 368
 369         res_data = (struct res_acc_data *)data;
 370         sch = get_subchannel_by_schid(schid);
 371         if (!sch)
 372                 /* Check if a subchannel is newly available. */
 373                 return s390_process_res_acc_new_sch(schid);
 374
 375         spin_lock_irq(&sch->lock);
 376
 377         chp_mask = s390_process_res_acc_sch(res_data, sch);
 378
 379         if (chp_mask == 0) {
 380                 spin_unlock_irq(&sch->lock);
 381                 put_device(&sch->dev);
 382                 return 0;
 383         }
 384         old_lpm = sch->lpm;
 385         sch->lpm = ((sch->schib.pmcw.pim &
 386                      sch->schib.pmcw.pam &
 387                      sch->schib.pmcw.pom)
 388                     | chp_mask) & sch->opm;
 389         if (!old_lpm && sch->lpm)
 390                 device_trigger_reprobe(sch);
 391         else if (sch->driver && sch->driver->verify)
 392                 sch->driver->verify(&sch->dev);
 393
 394         spin_unlock_irq(&sch->lock);
 395         put_device(&sch->dev);
 396         return 0;
 397 }
 398
 399
 400 static int
 401 s390_process_res_acc (struct res_acc_data *res_data)
 402 {
 403         int rc;
 404         char dbf_txt[15];
 405
 406         sprintf(dbf_txt, "accpr%x", res_data->chp->id);
 407         CIO_TRACE_EVENT( 2, dbf_txt);
 408         if (res_data->fla != 0) {
 409                 sprintf(dbf_txt, "fla%x", res_data->fla);
 410                 CIO_TRACE_EVENT( 2, dbf_txt);
 411         }
 412
 413         /*
 414          * I/O resources may have become accessible.
 415          * Scan through all subchannels that may be concerned and
 416          * do a validation on those.
 417          * The more information we have (info), the less scanning
 418          * will we have to do.
 419          */
 420         rc = for_each_subchannel(__s390_process_res_acc, res_data);
 421         if (css_slow_subchannels_exist())
 422                 rc = -EAGAIN;
 423         else if (rc != -EAGAIN)
 424                 rc = 0;
 425         return rc;
 426 }
 427
 428 static int
 429 __get_chpid_from_lir(void *data)
 430 {
 431         struct lir {
 432                 u8  iq;
 433                 u8  ic;
 434                 u16 sci;
 435                 /* incident-node descriptor */
 436                 u32 indesc[28];
 437                 /* attached-node descriptor */
 438                 u32 andesc[28];
 439                 /* incident-specific information */
 440                 u32 isinfo[28];
 441         } *lir;
 442
 443         lir = (struct lir*) data;
 444         if (!(lir->iq&0x80))
 445                 /* NULL link incident record */
 446                 return -EINVAL;
 447         if (!(lir->indesc[0]&0xc0000000))
 448                 /* node descriptor not valid */
 449                 return -EINVAL;
 450         if (!(lir->indesc[0]&0x10000000))
 451                 /* don't handle device-type nodes - FIXME */
 452                 return -EINVAL;
 453         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
 454
 455         return (u16) (lir->indesc[0]&0x000000ff);
 456 }
 457
 458 int
 459 chsc_process_crw(void)
 460 {
 461         int chpid, ret;
 462         struct res_acc_data res_data;
 463         struct {
 464                 struct chsc_header request;
 465                 u32 reserved1;
 466                 u32 reserved2;
 467                 u32 reserved3;
 468                 struct chsc_header response;
 469                 u32 reserved4;
 470                 u8  flags;
 471                 u8  vf;         /* validity flags */
 472                 u8  rs;         /* reporting source */
 473                 u8  cc;         /* content code */
 474                 u16 fla;        /* full link address */
 475                 u16 rsid;       /* reporting source id */
 476                 u32 reserved5;
 477                 u32 reserved6;
 478                 u32 ccdf[96];   /* content-code dependent field */
 479                 /* ccdf has to be big enough for a link-incident record */
 480         } *sei_area;
 481
 482         if (!sei_page)
 483                 return 0;
 484         /*
 485          * build the chsc request block for store event information
 486          * and do the call
 487          * This function is only called by the machine check handler thread,
 488          * so we don't need locking for the sei_page.
 489          */
 490         sei_area = sei_page;
 491
 492         CIO_TRACE_EVENT( 2, "prcss");
 493         ret = 0;
 494         do {
 495                 int ccode, status;
 496                 struct device *dev;
 497                 memset(sei_area, 0, sizeof(*sei_area));
 498                 memset(&res_data, 0, sizeof(struct res_acc_data));
 499                 sei_area->request.length = 0x0010;
 500                 sei_area->request.code = 0x000e;
 501
 502                 ccode = chsc(sei_area);
 503                 if (ccode > 0)
 504                         return 0;
 505
 506                 switch (sei_area->response.code) {
 507                         /* for debug purposes, check for problems */
 508                 case 0x0001:
 509                         CIO_CRW_EVENT(4, "chsc_process_crw: event information "
 510                                         "successfully stored\n");
 511                         break; /* everything ok */
 512                 case 0x0002:
 513                         CIO_CRW_EVENT(2,
 514                                       "chsc_process_crw: invalid command!\n");
 515                         return 0;
 516                 case 0x0003:
 517                         CIO_CRW_EVENT(2, "chsc_process_crw: error in chsc "
 518                                       "request block!\n");
 519                         return 0;
 520                 case 0x0005:
 521                         CIO_CRW_EVENT(2, "chsc_process_crw: no event "
 522                                       "information stored\n");
 523                         return 0;
 524                 default:
 525                         CIO_CRW_EVENT(2, "chsc_process_crw: chsc response %d\n",
 526                                       sei_area->response.code);
 527                         return 0;
 528                 }
 529
 530                 /* Check if we might have lost some information. */
 531                 if (sei_area->flags & 0x40)
 532                         CIO_CRW_EVENT(2, "chsc_process_crw: Event information "
 533                                        "has been lost due to overflow!\n");
 534
 535                 if (sei_area->rs != 4) {
 536                         CIO_CRW_EVENT(2, "chsc_process_crw: reporting source "
 537                                       "(%04X) isn't a chpid!\n",
 538                                       sei_area->rsid);
 539                         continue;
 540                 }
 541
 542                 /* which kind of information was stored? */
 543                 switch (sei_area->cc) {
 544                 case 1: /* link incident*/
 545                         CIO_CRW_EVENT(4, "chsc_process_crw: "
 546                                       "channel subsystem reports link incident,"
 547                                       " reporting source is chpid %x\n",
 548                                       sei_area->rsid);
 549                         chpid = __get_chpid_from_lir(sei_area->ccdf);
 550                         if (chpid < 0)
 551                                 CIO_CRW_EVENT(4, "%s: Invalid LIR, skipping\n",
 552                                               __FUNCTION__);
 553                         else
 554                                 s390_set_chpid_offline(chpid);
 555                         break;
 556
 557                 case 2: /* i/o resource accessibiliy */
 558                         CIO_CRW_EVENT(4, "chsc_process_crw: "
 559                                       "channel subsystem reports some I/O "
 560                                       "devices may have become accessible\n");
 561                         pr_debug("Data received after sei: \n");
 562                         pr_debug("Validity flags: %x\n", sei_area->vf);
 563
 564                         /* allocate a new channel path structure, if needed */
 565                         status = get_chp_status(sei_area->rsid);
 566                         if (status < 0)
 567                                 new_channel_path(sei_area->rsid);
 568                         else if (!status)
 569                                 break;
 570                         dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
 571                         res_data.chp = to_channelpath(dev);
 572                         pr_debug("chpid: %x", sei_area->rsid);
 573                         if ((sei_area->vf & 0xc0) != 0) {
 574                                 res_data.fla = sei_area->fla;
 575                                 if ((sei_area->vf & 0xc0) == 0xc0) {
 576                                         pr_debug(" full link addr: %x",
 577                                                  sei_area->fla);
 578                                         res_data.fla_mask = 0xffff;
 579                                 } else {
 580                                         pr_debug(" link addr: %x",
 581                                                  sei_area->fla);
 582                                         res_data.fla_mask = 0xff00;
 583                                 }
 584                         }
 585                         ret = s390_process_res_acc(&res_data);
 586                         pr_debug("\n\n");
 587                         put_device(dev);
 588                         break;
 589
 590                 default: /* other stuff */
 591                         CIO_CRW_EVENT(4, "chsc_process_crw: event %d\n",
 592                                       sei_area->cc);
 593                         break;
 594                 }
 595         } while (sei_area->flags & 0x80);
 596         return ret;
 597 }
 598
 599 static inline int
 600 __chp_add_new_sch(struct subchannel_id schid)
 601 {
 602         struct schib schib;
 603         int ret;
 604
 605         if (stsch(schid, &schib))
 606                 /* We're through */
 607                 return need_rescan ? -EAGAIN : -ENXIO;
 608
 609         /* Put it on the slow path. */
 610         ret = css_enqueue_subchannel_slow(schid);
 611         if (ret) {
 612                 css_clear_subchannel_slow_list();
 613                 need_rescan = 1;
 614                 return -EAGAIN;
 615         }
 616         return 0;
 617 }
 618
 619
 620 static int
 621 __chp_add(struct subchannel_id schid, void *data)
 622 {
 623         int i;
 624         struct channel_path *chp;
 625         struct subchannel *sch;
 626
 627         chp = (struct channel_path *)data;
 628         sch = get_subchannel_by_schid(schid);
 629         if (!sch)
 630                 /* Check if the subchannel is now available. */
 631                 return __chp_add_new_sch(schid);
 632         spin_lock_irq(&sch->lock);
 633         for (i=0; i<8; i++)
 634                 if (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         if (i==8) {
 643                 spin_unlock_irq(&sch->lock);
 644                 return 0;
 645         }
 646         sch->lpm = ((sch->schib.pmcw.pim &
 647                      sch->schib.pmcw.pam &
 648                      sch->schib.pmcw.pom)
 649                     | 0x80 >> i) & sch->opm;
 650
 651         if (sch->driver && sch->driver->verify)
 652                 sch->driver->verify(&sch->dev);
 653
 654         spin_unlock_irq(&sch->lock);
 655         put_device(&sch->dev);
 656         return 0;
 657 }
 658
 659 static int
 660 chp_add(int chpid)
 661 {
 662         int rc;
 663         char dbf_txt[15];
 664         struct device *dev;
 665
 666         if (!get_chp_status(chpid))
 667                 return 0; /* no need to do the rest */
 668
 669         sprintf(dbf_txt, "cadd%x", chpid);
 670         CIO_TRACE_EVENT(2, dbf_txt);
 671
 672         dev = get_device(&css[0]->chps[chpid]->dev);
 673         rc = for_each_subchannel(__chp_add, to_channelpath(dev));
 674         if (css_slow_subchannels_exist())
 675                 rc = -EAGAIN;
 676         if (rc != -EAGAIN)
 677                 rc = 0;
 678         put_device(dev);
 679         return rc;
 680 }
 681
 682 /*
 683  * Handling of crw machine checks with channel path source.
 684  */
 685 int
 686 chp_process_crw(int chpid, int on)
 687 {
 688         if (on == 0) {
 689                 /* Path has gone. We use the link incident routine.*/
 690                 s390_set_chpid_offline(chpid);
 691                 return 0; /* De-register is async anyway. */
 692         }
 693         /*
 694          * Path has come. Allocate a new channel path structure,
 695          * if needed.
 696          */
 697         if (get_chp_status(chpid) < 0)
 698                 new_channel_path(chpid);
 699         /* Avoid the extra overhead in process_rec_acc. */
 700         return chp_add(chpid);
 701 }
 702
 703 static inline int
 704 __check_for_io_and_kill(struct subchannel *sch, int index)
 705 {
 706         int cc;
 707
 708         if (!device_is_online(sch))
 709                 /* cio could be doing I/O. */
 710                 return 0;
 711         cc = stsch(sch->schid, &sch->schib);
 712         if (cc)
 713                 return 0;
 714         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
 715                 device_set_waiting(sch);
 716                 return 1;
 717         }
 718         return 0;
 719 }
 720
 721 static inline void
 722 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
 723 {
 724         int chp, old_lpm;
 725         unsigned long flags;
 726
 727         if (!sch->ssd_info.valid)
 728                 return;
 729
 730         spin_lock_irqsave(&sch->lock, flags);
 731         old_lpm = sch->lpm;
 732         for (chp = 0; chp < 8; chp++) {
 733                 if (sch->ssd_info.chpid[chp] != chpid)
 734                         continue;
 735
 736                 if (on) {
 737                         sch->opm |= (0x80 >> chp);
 738                         sch->lpm |= (0x80 >> chp);
 739                         if (!old_lpm)
 740                                 device_trigger_reprobe(sch);
 741                         else if (sch->driver && sch->driver->verify)
 742                                 sch->driver->verify(&sch->dev);
 743                 } else {
 744                         sch->opm &= ~(0x80 >> chp);
 745                         sch->lpm &= ~(0x80 >> chp);
 746                         /*
 747                          * Give running I/O a grace period in which it
 748                          * can successfully terminate, even using the
 749                          * just varied off path. Then kill it.
 750                          */
 751                         if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
 752                                 if (css_enqueue_subchannel_slow(sch->schid)) {
 753                                         css_clear_subchannel_slow_list();
 754                                         need_rescan = 1;
 755                                 }
 756                         } else if (sch->driver && sch->driver->verify)
 757                                 sch->driver->verify(&sch->dev);
 758                 }
 759                 break;
 760         }
 761         spin_unlock_irqrestore(&sch->lock, flags);
 762 }
 763
 764 static int
 765 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
 766 {
 767         struct subchannel *sch;
 768         __u8 *chpid;
 769
 770         sch = to_subchannel(dev);
 771         chpid = data;
 772
 773         __s390_subchannel_vary_chpid(sch, *chpid, 0);
 774         return 0;
 775 }
 776
 777 static int
 778 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
 779 {
 780         struct subchannel *sch;
 781         __u8 *chpid;
 782
 783         sch = to_subchannel(dev);
 784         chpid = data;
 785
 786         __s390_subchannel_vary_chpid(sch, *chpid, 1);
 787         return 0;
 788 }
 789
 790 static int
 791 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
 792 {
 793         struct schib schib;
 794         struct subchannel *sch;
 795
 796         sch = get_subchannel_by_schid(schid);
 797         if (sch) {
 798                 put_device(&sch->dev);
 799                 return 0;
 800         }
 801         if (stsch_err(schid, &schib))
 802                 /* We're through */
 803                 return -ENXIO;
 804         /* Put it on the slow path. */
 805         if (css_enqueue_subchannel_slow(schid)) {
 806                 css_clear_subchannel_slow_list();
 807                 need_rescan = 1;
 808                 return -EAGAIN;
 809         }
 810         return 0;
 811 }
 812
 813 /*
 814  * Function: s390_vary_chpid
 815  * Varies the specified chpid online or offline
 816  */
 817 static int
 818 s390_vary_chpid( __u8 chpid, int on)
 819 {
 820         char dbf_text[15];
 821         int status;
 822
 823         sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
 824         CIO_TRACE_EVENT( 2, dbf_text);
 825
 826         status = get_chp_status(chpid);
 827         if (status < 0) {
 828                 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
 829                 return -EINVAL;
 830         }
 831
 832         if (!on && !status) {
 833                 printk(KERN_ERR "chpid %x is already offline\n", chpid);
 834                 return -EINVAL;
 835         }
 836
 837         set_chp_logically_online(chpid, on);
 838
 839         /*
 840          * Redo PathVerification on the devices the chpid connects to
 841          */
 842
 843         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
 844                          s390_subchannel_vary_chpid_on :
 845                          s390_subchannel_vary_chpid_off);
 846         if (on)
 847                 /* Scan for new devices on varied on path. */
 848                 for_each_subchannel(__s390_vary_chpid_on, NULL);
 849         if (need_rescan || css_slow_subchannels_exist())
 850                 queue_work(slow_path_wq, &slow_path_work);
 851         return 0;
 852 }
 853
 854 /*
 855  * Channel measurement related functions
 856  */
 857 static ssize_t
 858 chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
 859                            size_t count)
 860 {
 861         struct channel_path *chp;
 862         unsigned int size;
 863
 864         chp = to_channelpath(container_of(kobj, struct device, kobj));
 865         if (!chp->cmg_chars)
 866                 return 0;
 867
 868         size = sizeof(struct cmg_chars);
 869
 870         if (off > size)
 871                 return 0;
 872         if (off + count > size)
 873                 count = size - off;
 874         memcpy(buf, chp->cmg_chars + off, count);
 875         return count;
 876 }
 877
 878 static struct bin_attribute chp_measurement_chars_attr = {
 879         .attr = {
 880                 .name = "measurement_chars",
 881                 .mode = S_IRUSR,
 882                 .owner = THIS_MODULE,
 883         },
 884         .size = sizeof(struct cmg_chars),
 885         .read = chp_measurement_chars_read,
 886 };
 887
 888 static void
 889 chp_measurement_copy_block(struct cmg_entry *buf,
 890                            struct channel_subsystem *css, int chpid)
 891 {
 892         void *area;
 893         struct cmg_entry *entry, reference_buf;
 894         int idx;
 895
 896         if (chpid < 128) {
 897                 area = css->cub_addr1;
 898                 idx = chpid;
 899         } else {
 900                 area = css->cub_addr2;
 901                 idx = chpid - 128;
 902         }
 903         entry = area + (idx * sizeof(struct cmg_entry));
 904         do {
 905                 memcpy(buf, entry, sizeof(*entry));
 906                 memcpy(&reference_buf, entry, sizeof(*entry));
 907         } while (reference_buf.values[0] != buf->values[0]);
 908 }
 909
 910 static ssize_t
 911 chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
 912 {
 913         struct channel_path *chp;
 914         struct channel_subsystem *css;
 915         unsigned int size;
 916
 917         chp = to_channelpath(container_of(kobj, struct device, kobj));
 918         css = to_css(chp->dev.parent);
 919
 920         size = sizeof(struct cmg_entry);
 921
 922         /* Only allow single reads. */
 923         if (off || count < size)
 924                 return 0;
 925         chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
 926         count = size;
 927         return count;
 928 }
 929
 930 static struct bin_attribute chp_measurement_attr = {
 931         .attr = {
 932                 .name = "measurement",
 933                 .mode = S_IRUSR,
 934                 .owner = THIS_MODULE,
 935         },
 936         .size = sizeof(struct cmg_entry),
 937         .read = chp_measurement_read,
 938 };
 939
 940 static void
 941 chsc_remove_chp_cmg_attr(struct channel_path *chp)
 942 {
 943         sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_chars_attr);
 944         sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_attr);
 945 }
 946
 947 static int
 948 chsc_add_chp_cmg_attr(struct channel_path *chp)
 949 {
 950         int ret;
 951
 952         ret = sysfs_create_bin_file(&chp->dev.kobj,
 953                                     &chp_measurement_chars_attr);
 954         if (ret)
 955                 return ret;
 956         ret = sysfs_create_bin_file(&chp->dev.kobj, &chp_measurement_attr);
 957         if (ret)
 958                 sysfs_remove_bin_file(&chp->dev.kobj,
 959                                       &chp_measurement_chars_attr);
 960         return ret;
 961 }
 962
 963 static void
 964 chsc_remove_cmg_attr(struct channel_subsystem *css)
 965 {
 966         int i;
 967
 968         for (i = 0; i <= __MAX_CHPID; i++) {
 969                 if (!css->chps[i])
 970                         continue;
 971                 chsc_remove_chp_cmg_attr(css->chps[i]);
 972         }
 973 }
 974
 975 static int
 976 chsc_add_cmg_attr(struct channel_subsystem *css)
 977 {
 978         int i, ret;
 979
 980         ret = 0;
 981         for (i = 0; i <= __MAX_CHPID; i++) {
 982                 if (!css->chps[i])
 983                         continue;
 984                 ret = chsc_add_chp_cmg_attr(css->chps[i]);
 985                 if (ret)
 986                         goto cleanup;
 987         }
 988         return ret;
 989 cleanup:
 990         for (--i; i >= 0; i--) {
 991                 if (!css->chps[i])
 992                         continue;
 993                 chsc_remove_chp_cmg_attr(css->chps[i]);
 994         }
 995         return ret;
 996 }
 997
 998
 999 static int
1000 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
1001 {
1002         struct {
1003                 struct chsc_header request;
1004                 u32 operation_code : 2;
1005                 u32 : 30;
1006                 u32 key : 4;
1007                 u32 : 28;
1008                 u32 zeroes1;
1009                 u32 cub_addr1;
1010                 u32 zeroes2;
1011                 u32 cub_addr2;
1012                 u32 reserved[13];
1013                 struct chsc_header response;
1014                 u32 status : 8;
1015                 u32 : 4;
1016                 u32 fmt : 4;
1017                 u32 : 16;
1018         } *secm_area;
1019         int ret, ccode;
1020
1021         secm_area = page;
1022         secm_area->request.length = 0x0050;
1023         secm_area->request.code = 0x0016;
1024
1025         secm_area->key = PAGE_DEFAULT_KEY;
1026         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
1027         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
1028
1029         secm_area->operation_code = enable ? 0 : 1;
1030
1031         ccode = chsc(secm_area);
1032         if (ccode > 0)
1033                 return (ccode == 3) ? -ENODEV : -EBUSY;
1034
1035         switch (secm_area->response.code) {
1036         case 0x0001: /* Success. */
1037                 ret = 0;
1038                 break;
1039         case 0x0003: /* Invalid block. */
1040         case 0x0007: /* Invalid format. */
1041         case 0x0008: /* Other invalid block. */
1042                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1043                 ret = -EINVAL;
1044                 break;
1045         case 0x0004: /* Command not provided in model. */
1046                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
1047                 ret = -EOPNOTSUPP;
1048                 break;
1049         case 0x0102: /* cub adresses incorrect */
1050                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
1051                 ret = -EINVAL;
1052                 break;
1053         case 0x0103: /* key error */
1054                 CIO_CRW_EVENT(2, "Access key error in secm\n");
1055                 ret = -EINVAL;
1056                 break;
1057         case 0x0105: /* error while starting */
1058                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
1059                 ret = -EIO;
1060                 break;
1061         default:
1062                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1063                               secm_area->response.code);
1064                 ret = -EIO;
1065         }
1066         return ret;
1067 }
1068
1069 int
1070 chsc_secm(struct channel_subsystem *css, int enable)
1071 {
1072         void  *secm_area;
1073         int ret;
1074
1075         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
1076         if (!secm_area)
1077                 return -ENOMEM;
1078
1079         mutex_lock(&css->mutex);
1080         if (enable && !css->cm_enabled) {
1081                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1082                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1083                 if (!css->cub_addr1 || !css->cub_addr2) {
1084                         free_page((unsigned long)css->cub_addr1);
1085                         free_page((unsigned long)css->cub_addr2);
1086                         free_page((unsigned long)secm_area);
1087                         mutex_unlock(&css->mutex);
1088                         return -ENOMEM;
1089                 }
1090         }
1091         ret = __chsc_do_secm(css, enable, secm_area);
1092         if (!ret) {
1093                 css->cm_enabled = enable;
1094                 if (css->cm_enabled) {
1095                         ret = chsc_add_cmg_attr(css);
1096                         if (ret) {
1097                                 memset(secm_area, 0, PAGE_SIZE);
1098                                 __chsc_do_secm(css, 0, secm_area);
1099                                 css->cm_enabled = 0;
1100                         }
1101                 } else
1102                         chsc_remove_cmg_attr(css);
1103         }
1104         if (enable && !css->cm_enabled) {
1105                 free_page((unsigned long)css->cub_addr1);
1106                 free_page((unsigned long)css->cub_addr2);
1107         }
1108         mutex_unlock(&css->mutex);
1109         free_page((unsigned long)secm_area);
1110         return ret;
1111 }
1112
1113 /*
1114  * Files for the channel path entries.
1115  */
1116 static ssize_t
1117 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
1118 {
1119         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1120
1121         if (!chp)
1122                 return 0;
1123         return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
1124                 sprintf(buf, "offline\n"));
1125 }
1126
1127 static ssize_t
1128 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
1129 {
1130         struct channel_path *cp = container_of(dev, struct channel_path, dev);
1131         char cmd[10];
1132         int num_args;
1133         int error;
1134
1135         num_args = sscanf(buf, "%5s", cmd);
1136         if (!num_args)
1137                 return count;
1138
1139         if (!strnicmp(cmd, "on", 2))
1140                 error = s390_vary_chpid(cp->id, 1);
1141         else if (!strnicmp(cmd, "off", 3))
1142                 error = s390_vary_chpid(cp->id, 0);
1143         else
1144                 error = -EINVAL;
1145
1146         return error < 0 ? error : count;
1147
1148 }
1149
1150 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
1151
1152 static ssize_t
1153 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
1154 {
1155         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1156
1157         if (!chp)
1158                 return 0;
1159         return sprintf(buf, "%x\n", chp->desc.desc);
1160 }
1161
1162 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
1163
1164 static ssize_t
1165 chp_cmg_show(struct device *dev, struct device_attribute *attr, char *buf)
1166 {
1167         struct channel_path *chp = to_channelpath(dev);
1168
1169         if (!chp)
1170                 return 0;
1171         if (chp->cmg == -1) /* channel measurements not available */
1172                 return sprintf(buf, "unknown\n");
1173         return sprintf(buf, "%x\n", chp->cmg);
1174 }
1175
1176 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
1177
1178 static ssize_t
1179 chp_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
1180 {
1181         struct channel_path *chp = to_channelpath(dev);
1182
1183         if (!chp)
1184                 return 0;
1185         if (chp->shared == -1) /* channel measurements not available */
1186                 return sprintf(buf, "unknown\n");
1187         return sprintf(buf, "%x\n", chp->shared);
1188 }
1189
1190 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
1191
1192 static struct attribute * chp_attrs[] = {
1193         &dev_attr_status.attr,
1194         &dev_attr_type.attr,
1195         &dev_attr_cmg.attr,
1196         &dev_attr_shared.attr,
1197         NULL,
1198 };
1199
1200 static struct attribute_group chp_attr_group = {
1201         .attrs = chp_attrs,
1202 };
1203
1204 static void
1205 chp_release(struct device *dev)
1206 {
1207         struct channel_path *cp;
1208
1209         cp = container_of(dev, struct channel_path, dev);
1210         kfree(cp);
1211 }
1212
1213 static int
1214 chsc_determine_channel_path_description(int chpid,
1215                                         struct channel_path_desc *desc)
1216 {
1217         int ccode, ret;
1218
1219         struct {
1220                 struct chsc_header request;
1221                 u32 : 24;
1222                 u32 first_chpid : 8;
1223                 u32 : 24;
1224                 u32 last_chpid : 8;
1225                 u32 zeroes1;
1226                 struct chsc_header response;
1227                 u32 zeroes2;
1228                 struct channel_path_desc desc;
1229         } *scpd_area;
1230
1231         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1232         if (!scpd_area)
1233                 return -ENOMEM;
1234
1235         scpd_area->request.length = 0x0010;
1236         scpd_area->request.code = 0x0002;
1237
1238         scpd_area->first_chpid = chpid;
1239         scpd_area->last_chpid = chpid;
1240
1241         ccode = chsc(scpd_area);
1242         if (ccode > 0) {
1243                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1244                 goto out;
1245         }
1246
1247         switch (scpd_area->response.code) {
1248         case 0x0001: /* Success. */
1249                 memcpy(desc, &scpd_area->desc,
1250                        sizeof(struct channel_path_desc));
1251                 ret = 0;
1252                 break;
1253         case 0x0003: /* Invalid block. */
1254         case 0x0007: /* Invalid format. */
1255         case 0x0008: /* Other invalid block. */
1256                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1257                 ret = -EINVAL;
1258                 break;
1259         case 0x0004: /* Command not provided in model. */
1260                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
1261                 ret = -EOPNOTSUPP;
1262                 break;
1263         default:
1264                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1265                               scpd_area->response.code);
1266                 ret = -EIO;
1267         }
1268 out:
1269         free_page((unsigned long)scpd_area);
1270         return ret;
1271 }
1272
1273 static void
1274 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1275                           struct cmg_chars *chars)
1276 {
1277         switch (chp->cmg) {
1278         case 2:
1279         case 3:
1280                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1281                                          GFP_KERNEL);
1282                 if (chp->cmg_chars) {
1283                         int i, mask;
1284                         struct cmg_chars *cmg_chars;
1285
1286                         cmg_chars = chp->cmg_chars;
1287                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1288                                 mask = 0x80 >> (i + 3);
1289                                 if (cmcv & mask)
1290                                         cmg_chars->values[i] = chars->values[i];
1291                                 else
1292                                         cmg_chars->values[i] = 0;
1293                         }
1294                 }
1295                 break;
1296         default:
1297                 /* No cmg-dependent data. */
1298                 break;
1299         }
1300 }
1301
1302 static int
1303 chsc_get_channel_measurement_chars(struct channel_path *chp)
1304 {
1305         int ccode, ret;
1306
1307         struct {
1308                 struct chsc_header request;
1309                 u32 : 24;
1310                 u32 first_chpid : 8;
1311                 u32 : 24;
1312                 u32 last_chpid : 8;
1313                 u32 zeroes1;
1314                 struct chsc_header response;
1315                 u32 zeroes2;
1316                 u32 not_valid : 1;
1317                 u32 shared : 1;
1318                 u32 : 22;
1319                 u32 chpid : 8;
1320                 u32 cmcv : 5;
1321                 u32 : 11;
1322                 u32 cmgq : 8;
1323                 u32 cmg : 8;
1324                 u32 zeroes3;
1325                 u32 data[NR_MEASUREMENT_CHARS];
1326         } *scmc_area;
1327
1328         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1329         if (!scmc_area)
1330                 return -ENOMEM;
1331
1332         scmc_area->request.length = 0x0010;
1333         scmc_area->request.code = 0x0022;
1334
1335         scmc_area->first_chpid = chp->id;
1336         scmc_area->last_chpid = chp->id;
1337
1338         ccode = chsc(scmc_area);
1339         if (ccode > 0) {
1340                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1341                 goto out;
1342         }
1343
1344         switch (scmc_area->response.code) {
1345         case 0x0001: /* Success. */
1346                 if (!scmc_area->not_valid) {
1347                         chp->cmg = scmc_area->cmg;
1348                         chp->shared = scmc_area->shared;
1349                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1350                                                   (struct cmg_chars *)
1351                                                   &scmc_area->data);
1352                 } else {
1353                         chp->cmg = -1;
1354                         chp->shared = -1;
1355                 }
1356                 ret = 0;
1357                 break;
1358         case 0x0003: /* Invalid block. */
1359         case 0x0007: /* Invalid format. */
1360         case 0x0008: /* Invalid bit combination. */
1361                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1362                 ret = -EINVAL;
1363                 break;
1364         case 0x0004: /* Command not provided. */
1365                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1366                 ret = -EOPNOTSUPP;
1367                 break;
1368         default:
1369                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1370                               scmc_area->response.code);
1371                 ret = -EIO;
1372         }
1373 out:
1374         free_page((unsigned long)scmc_area);
1375         return ret;
1376 }
1377
1378 /*
1379  * Entries for chpids on the system bus.
1380  * This replaces /proc/chpids.
1381  */
1382 static int
1383 new_channel_path(int chpid)
1384 {
1385         struct channel_path *chp;
1386         int ret;
1387
1388         chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
1389         if (!chp)
1390                 return -ENOMEM;
1391
1392         /* fill in status, etc. */
1393         chp->id = chpid;
1394         chp->state = 1;
1395         chp->dev.parent = &css[0]->device;
1396         chp->dev.release = chp_release;
1397         snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1398
1399         /* Obtain channel path description and fill it in. */
1400         ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1401         if (ret)
1402                 goto out_free;
1403         /* Get channel-measurement characteristics. */
1404         if (css_characteristics_avail && css_chsc_characteristics.scmc
1405             && css_chsc_characteristics.secm) {
1406                 ret = chsc_get_channel_measurement_chars(chp);
1407                 if (ret)
1408                         goto out_free;
1409         } else {
1410                 static int msg_done;
1411
1412                 if (!msg_done) {
1413                         printk(KERN_WARNING "cio: Channel measurements not "
1414                                "available, continuing.\n");
1415                         msg_done = 1;
1416                 }
1417                 chp->cmg = -1;
1418         }
1419
1420         /* make it known to the system */
1421         ret = device_register(&chp->dev);
1422         if (ret) {
1423                 printk(KERN_WARNING "%s: could not register %02x\n",
1424                        __func__, chpid);
1425                 goto out_free;
1426         }
1427         ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1428         if (ret) {
1429                 device_unregister(&chp->dev);
1430                 goto out_free;
1431         }
1432         mutex_lock(&css[0]->mutex);
1433         if (css[0]->cm_enabled) {
1434                 ret = chsc_add_chp_cmg_attr(chp);
1435                 if (ret) {
1436                         sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
1437                         device_unregister(&chp->dev);
1438                         mutex_unlock(&css[0]->mutex);
1439                         goto out_free;
1440                 }
1441         }
1442         css[0]->chps[chpid] = chp;
1443         mutex_unlock(&css[0]->mutex);
1444         return ret;
1445 out_free:
1446         kfree(chp);
1447         return ret;
1448 }
1449
1450 void *
1451 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1452 {
1453         struct channel_path *chp;
1454         struct channel_path_desc *desc;
1455
1456         chp = css[0]->chps[sch->schib.pmcw.chpid[chp_no]];
1457         if (!chp)
1458                 return NULL;
1459         desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1460         if (!desc)
1461                 return NULL;
1462         memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1463         return desc;
1464 }
1465
1466 static int reset_channel_path(struct channel_path *chp)
1467 {
1468         int cc;
1469
1470         cc = rchp(chp->id);
1471         switch (cc) {
1472         case 0:
1473                 return 0;
1474         case 2:
1475                 return -EBUSY;
1476         default:
1477                 return -ENODEV;
1478         }
1479 }
1480
1481 static void reset_channel_paths_css(struct channel_subsystem *css)
1482 {
1483         int i;
1484
1485         for (i = 0; i <= __MAX_CHPID; i++) {
1486                 if (css->chps[i])
1487                         reset_channel_path(css->chps[i]);
1488         }
1489 }
1490
1491 void cio_reset_channel_paths(void)
1492 {
1493         int i;
1494
1495         for (i = 0; i <= __MAX_CSSID; i++) {
1496                 if (css[i] && css[i]->valid)
1497                         reset_channel_paths_css(css[i]);
1498         }
1499 }
1500
1501 static int __init
1502 chsc_alloc_sei_area(void)
1503 {
1504         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1505         if (!sei_page)
1506                 printk(KERN_WARNING"Can't allocate page for processing of " \
1507                        "chsc machine checks!\n");
1508         return (sei_page ? 0 : -ENOMEM);
1509 }
1510
1511 int __init
1512 chsc_enable_facility(int operation_code)
1513 {
1514         int ret;
1515         struct {
1516                 struct chsc_header request;
1517                 u8 reserved1:4;
1518                 u8 format:4;
1519                 u8 reserved2;
1520                 u16 operation_code;
1521                 u32 reserved3;
1522                 u32 reserved4;
1523                 u32 operation_data_area[252];
1524                 struct chsc_header response;
1525                 u32 reserved5:4;
1526                 u32 format2:4;
1527                 u32 reserved6:24;
1528         } *sda_area;
1529
1530         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1531         if (!sda_area)
1532                 return -ENOMEM;
1533         sda_area->request.length = 0x0400;
1534         sda_area->request.code = 0x0031;
1535         sda_area->operation_code = operation_code;
1536
1537         ret = chsc(sda_area);
1538         if (ret > 0) {
1539                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1540                 goto out;
1541         }
1542         switch (sda_area->response.code) {
1543         case 0x0001: /* everything ok */
1544                 ret = 0;
1545                 break;
1546         case 0x0003: /* invalid request block */
1547         case 0x0007:
1548                 ret = -EINVAL;
1549                 break;
1550         case 0x0004: /* command not provided */
1551         case 0x0101: /* facility not provided */
1552                 ret = -EOPNOTSUPP;
1553                 break;
1554         default: /* something went wrong */
1555                 ret = -EIO;
1556         }
1557  out:
1558         free_page((unsigned long)sda_area);
1559         return ret;
1560 }
1561
1562 subsys_initcall(chsc_alloc_sei_area);
1563
1564 struct css_general_char css_general_characteristics;
1565 struct css_chsc_char css_chsc_characteristics;
1566
1567 int __init
1568 chsc_determine_css_characteristics(void)
1569 {
1570         int result;
1571         struct {
1572                 struct chsc_header request;
1573                 u32 reserved1;
1574                 u32 reserved2;
1575                 u32 reserved3;
1576                 struct chsc_header response;
1577                 u32 reserved4;
1578                 u32 general_char[510];
1579                 u32 chsc_char[518];
1580         } *scsc_area;
1581
1582         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1583         if (!scsc_area) {
1584                 printk(KERN_WARNING"cio: Was not able to determine available" \
1585                        "CHSCs due to no memory.\n");
1586                 return -ENOMEM;
1587         }
1588
1589         scsc_area->request.length = 0x0010;
1590         scsc_area->request.code = 0x0010;
1591
1592         result = chsc(scsc_area);
1593         if (result) {
1594                 printk(KERN_WARNING"cio: Was not able to determine " \
1595                        "available CHSCs, cc=%i.\n", result);
1596                 result = -EIO;
1597                 goto exit;
1598         }
1599
1600         if (scsc_area->response.code != 1) {
1601                 printk(KERN_WARNING"cio: Was not able to determine " \
1602                        "available CHSCs.\n");
1603                 result = -EIO;
1604                 goto exit;
1605         }
1606         memcpy(&css_general_characteristics, scsc_area->general_char,
1607                sizeof(css_general_characteristics));
1608         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1609                sizeof(css_chsc_characteristics));
1610 exit:
1611         free_page ((unsigned long) scsc_area);
1612         return result;
1613 }
1614
1615 EXPORT_SYMBOL_GPL(css_general_characteristics);
1616 EXPORT_SYMBOL_GPL(css_chsc_characteristics);