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 #include <asm/chpid.h>
  19
  20 #include "css.h"
  21 #include "cio.h"
  22 #include "cio_debug.h"
  23 #include "ioasm.h"
  24 #include "chp.h"
  25 #include "chsc.h"
  26
  27 static void *sei_page;
  28
  29 /* FIXME: this is _always_ called for every subchannel. shouldn't we
  30  *        process more than one at a time? */
  31 static int
  32 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
  33 {
  34         int ccode, j;
  35
  36         struct {
  37                 struct chsc_header request;
  38                 u16 reserved1a:10;
  39                 u16 ssid:2;
  40                 u16 reserved1b:4;
  41                 u16 f_sch;        /* first subchannel */
  42                 u16 reserved2;
  43                 u16 l_sch;        /* last subchannel */
  44                 u32 reserved3;
  45                 struct chsc_header response;
  46                 u32 reserved4;
  47                 u8 sch_valid : 1;
  48                 u8 dev_valid : 1;
  49                 u8 st        : 3; /* subchannel type */
  50                 u8 zeroes    : 3;
  51                 u8  unit_addr;    /* unit address */
  52                 u16 devno;        /* device number */
  53                 u8 path_mask;
  54                 u8 fla_valid_mask;
  55                 u16 sch;          /* subchannel */
  56                 u8 chpid[8];      /* chpids 0-7 */
  57                 u16 fla[8];       /* full link addresses 0-7 */
  58         } __attribute__ ((packed)) *ssd_area;
  59
  60         ssd_area = page;
  61
  62         ssd_area->request.length = 0x0010;
  63         ssd_area->request.code = 0x0004;
  64
  65         ssd_area->ssid = sch->schid.ssid;
  66         ssd_area->f_sch = sch->schid.sch_no;
  67         ssd_area->l_sch = sch->schid.sch_no;
  68
  69         ccode = chsc(ssd_area);
  70         if (ccode > 0) {
  71                 pr_debug("chsc returned with ccode = %d\n", ccode);
  72                 return (ccode == 3) ? -ENODEV : -EBUSY;
  73         }
  74
  75         switch (ssd_area->response.code) {
  76         case 0x0001: /* everything ok */
  77                 break;
  78         case 0x0002:
  79                 CIO_CRW_EVENT(2, "Invalid command!\n");
  80                 return -EINVAL;
  81         case 0x0003:
  82                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
  83                 return -EINVAL;
  84         case 0x0004:
  85                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
  86                 return -EOPNOTSUPP;
  87         default:
  88                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
  89                               ssd_area->response.code);
  90                 return -EIO;
  91         }
  92
  93         /*
  94          * ssd_area->st stores the type of the detected
  95          * subchannel, with the following definitions:
  96          *
  97          * 0: I/O subchannel:     All fields have meaning
  98          * 1: CHSC subchannel:    Only sch_val, st and sch
  99          *                        have meaning
 100          * 2: Message subchannel: All fields except unit_addr
 101          *                        have meaning
 102          * 3: ADM subchannel:     Only sch_val, st and sch
 103          *                        have meaning
 104          *
 105          * Other types are currently undefined.
 106          */
 107         if (ssd_area->st > 3) { /* uhm, that looks strange... */
 108                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
 109                               " for sch 0.%x.%04x\n", ssd_area->st,
 110                               sch->schid.ssid, sch->schid.sch_no);
 111                 /*
 112                  * There may have been a new subchannel type defined in the
 113                  * time since this code was written; since we don't know which
 114                  * fields have meaning and what to do with it we just jump out
 115                  */
 116                 return 0;
 117         } else {
 118                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
 119                 CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
 120                               sch->schid.ssid, sch->schid.sch_no,
 121                               type[ssd_area->st]);
 122
 123                 sch->ssd_info.valid = 1;
 124                 sch->ssd_info.type = ssd_area->st;
 125         }
 126
 127         if (ssd_area->st == 0 || ssd_area->st == 2) {
 128                 for (j = 0; j < 8; j++) {
 129                         if (!((0x80 >> j) & ssd_area->path_mask &
 130                               ssd_area->fla_valid_mask))
 131                                 continue;
 132                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
 133                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
 134                 }
 135         }
 136         return 0;
 137 }
 138
 139 int
 140 css_get_ssd_info(struct subchannel *sch)
 141 {
 142         int ret;
 143         void *page;
 144
 145         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 146         if (!page)
 147                 return -ENOMEM;
 148         spin_lock_irq(sch->lock);
 149         ret = chsc_get_sch_desc_irq(sch, page);
 150         if (ret) {
 151                 static int cio_chsc_err_msg;
 152
 153                 if (!cio_chsc_err_msg) {
 154                         printk(KERN_ERR
 155                                "chsc_get_sch_descriptions:"
 156                                " Error %d while doing chsc; "
 157                                "processing some machine checks may "
 158                                "not work\n", ret);
 159                         cio_chsc_err_msg = 1;
 160                 }
 161         }
 162         spin_unlock_irq(sch->lock);
 163         free_page((unsigned long)page);
 164         if (!ret) {
 165                 int j, mask;
 166                 struct chp_id chpid;
 167
 168                 chp_id_init(&chpid);
 169                 /* Allocate channel path structures, if needed. */
 170                 for (j = 0; j < 8; j++) {
 171                         mask = 0x80 >> j;
 172                         chpid.id = sch->ssd_info.chpid[j];
 173                         if ((sch->schib.pmcw.pim & mask) &&
 174                             !chp_is_registered(chpid))
 175                                 chp_new(chpid);
 176                 }
 177         }
 178         return ret;
 179 }
 180
 181 static int check_for_io_on_path(struct subchannel *sch, int mask)
 182 {
 183         int cc;
 184
 185         cc = stsch(sch->schid, &sch->schib);
 186         if (cc)
 187                 return 0;
 188         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == mask)
 189                 return 1;
 190         return 0;
 191 }
 192
 193 static void terminate_internal_io(struct subchannel *sch)
 194 {
 195         if (cio_clear(sch)) {
 196                 /* Recheck device in case clear failed. */
 197                 sch->lpm = 0;
 198                 if (device_trigger_verify(sch) != 0) {
 199                         if(css_enqueue_subchannel_slow(sch->schid)) {
 200                                 css_clear_subchannel_slow_list();
 201                                 need_rescan = 1;
 202                         }
 203                 }
 204                 return;
 205         }
 206         /* Request retry of internal operation. */
 207         device_set_intretry(sch);
 208         /* Call handler. */
 209         if (sch->driver && sch->driver->termination)
 210                 sch->driver->termination(&sch->dev);
 211 }
 212
 213 static int
 214 s390_subchannel_remove_chpid(struct device *dev, void *data)
 215 {
 216         int j;
 217         int mask;
 218         struct subchannel *sch;
 219         struct chp_id *chpid;
 220         struct schib schib;
 221
 222         sch = to_subchannel(dev);
 223         chpid = data;
 224         for (j = 0; j < 8; j++) {
 225                 mask = 0x80 >> j;
 226                 if ((sch->schib.pmcw.pim & mask) &&
 227                     (sch->schib.pmcw.chpid[j] == chpid->id))
 228                         break;
 229         }
 230         if (j >= 8)
 231                 return 0;
 232
 233         spin_lock_irq(sch->lock);
 234
 235         stsch(sch->schid, &schib);
 236         if (!schib.pmcw.dnv)
 237                 goto out_unreg;
 238         memcpy(&sch->schib, &schib, sizeof(struct schib));
 239         /* Check for single path devices. */
 240         if (sch->schib.pmcw.pim == 0x80)
 241                 goto out_unreg;
 242
 243         if (check_for_io_on_path(sch, mask)) {
 244                 if (device_is_online(sch))
 245                         device_kill_io(sch);
 246                 else {
 247                         terminate_internal_io(sch);
 248                         /* Re-start path verification. */
 249                         if (sch->driver && sch->driver->verify)
 250                                 sch->driver->verify(&sch->dev);
 251                 }
 252         } else {
 253                 /* trigger path verification. */
 254                 if (sch->driver && sch->driver->verify)
 255                         sch->driver->verify(&sch->dev);
 256                 else if (sch->lpm == mask)
 257                         goto out_unreg;
 258         }
 259
 260         spin_unlock_irq(sch->lock);
 261         return 0;
 262
 263 out_unreg:
 264         sch->lpm = 0;
 265         if (css_enqueue_subchannel_slow(sch->schid)) {
 266                 css_clear_subchannel_slow_list();
 267                 need_rescan = 1;
 268         }
 269         spin_unlock_irq(sch->lock);
 270         return 0;
 271 }
 272
 273 void chsc_chp_offline(struct chp_id chpid)
 274 {
 275         char dbf_txt[15];
 276
 277         sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
 278         CIO_TRACE_EVENT(2, dbf_txt);
 279
 280         if (chp_get_status(chpid) <= 0)
 281                 return;
 282         bus_for_each_dev(&css_bus_type, NULL, &chpid,
 283                          s390_subchannel_remove_chpid);
 284
 285         if (need_rescan || css_slow_subchannels_exist())
 286                 queue_work(slow_path_wq, &slow_path_work);
 287 }
 288
 289 struct res_acc_data {
 290         struct chp_id chpid;
 291         u32 fla_mask;
 292         u16 fla;
 293 };
 294
 295 static int s390_process_res_acc_sch(struct res_acc_data *res_data,
 296                                     struct subchannel *sch)
 297 {
 298         int found;
 299         int chp;
 300         int ccode;
 301
 302         found = 0;
 303         for (chp = 0; chp <= 7; chp++)
 304                 /*
 305                  * check if chpid is in information updated by ssd
 306                  */
 307                 if (sch->ssd_info.valid &&
 308                     sch->ssd_info.chpid[chp] == res_data->chpid.id &&
 309                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
 310                     == res_data->fla) {
 311                         found = 1;
 312                         break;
 313                 }
 314
 315         if (found == 0)
 316                 return 0;
 317
 318         /*
 319          * Do a stsch to update our subchannel structure with the
 320          * new path information and eventually check for logically
 321          * offline chpids.
 322          */
 323         ccode = stsch(sch->schid, &sch->schib);
 324         if (ccode > 0)
 325                 return 0;
 326
 327         return 0x80 >> chp;
 328 }
 329
 330 static int
 331 s390_process_res_acc_new_sch(struct subchannel_id schid)
 332 {
 333         struct schib schib;
 334         int ret;
 335         /*
 336          * We don't know the device yet, but since a path
 337          * may be available now to the device we'll have
 338          * to do recognition again.
 339          * Since we don't have any idea about which chpid
 340          * that beast may be on we'll have to do a stsch
 341          * on all devices, grr...
 342          */
 343         if (stsch_err(schid, &schib))
 344                 /* We're through */
 345                 return need_rescan ? -EAGAIN : -ENXIO;
 346
 347         /* Put it on the slow path. */
 348         ret = css_enqueue_subchannel_slow(schid);
 349         if (ret) {
 350                 css_clear_subchannel_slow_list();
 351                 need_rescan = 1;
 352                 return -EAGAIN;
 353         }
 354         return 0;
 355 }
 356
 357 static int
 358 __s390_process_res_acc(struct subchannel_id schid, void *data)
 359 {
 360         int chp_mask, old_lpm;
 361         struct res_acc_data *res_data;
 362         struct subchannel *sch;
 363
 364         res_data = data;
 365         sch = get_subchannel_by_schid(schid);
 366         if (!sch)
 367                 /* Check if a subchannel is newly available. */
 368                 return s390_process_res_acc_new_sch(schid);
 369
 370         spin_lock_irq(sch->lock);
 371
 372         chp_mask = s390_process_res_acc_sch(res_data, sch);
 373
 374         if (chp_mask == 0) {
 375                 spin_unlock_irq(sch->lock);
 376                 put_device(&sch->dev);
 377                 return 0;
 378         }
 379         old_lpm = sch->lpm;
 380         sch->lpm = ((sch->schib.pmcw.pim &
 381                      sch->schib.pmcw.pam &
 382                      sch->schib.pmcw.pom)
 383                     | chp_mask) & sch->opm;
 384         if (!old_lpm && sch->lpm)
 385                 device_trigger_reprobe(sch);
 386         else if (sch->driver && sch->driver->verify)
 387                 sch->driver->verify(&sch->dev);
 388
 389         spin_unlock_irq(sch->lock);
 390         put_device(&sch->dev);
 391         return 0;
 392 }
 393
 394
 395 static int
 396 s390_process_res_acc (struct res_acc_data *res_data)
 397 {
 398         int rc;
 399         char dbf_txt[15];
 400
 401         sprintf(dbf_txt, "accpr%x.%02x", res_data->chpid.cssid,
 402                 res_data->chpid.id);
 403         CIO_TRACE_EVENT( 2, dbf_txt);
 404         if (res_data->fla != 0) {
 405                 sprintf(dbf_txt, "fla%x", res_data->fla);
 406                 CIO_TRACE_EVENT( 2, dbf_txt);
 407         }
 408
 409         /*
 410          * I/O resources may have become accessible.
 411          * Scan through all subchannels that may be concerned and
 412          * do a validation on those.
 413          * The more information we have (info), the less scanning
 414          * will we have to do.
 415          */
 416         rc = for_each_subchannel(__s390_process_res_acc, res_data);
 417         if (css_slow_subchannels_exist())
 418                 rc = -EAGAIN;
 419         else if (rc != -EAGAIN)
 420                 rc = 0;
 421         return rc;
 422 }
 423
 424 static int
 425 __get_chpid_from_lir(void *data)
 426 {
 427         struct lir {
 428                 u8  iq;
 429                 u8  ic;
 430                 u16 sci;
 431                 /* incident-node descriptor */
 432                 u32 indesc[28];
 433                 /* attached-node descriptor */
 434                 u32 andesc[28];
 435                 /* incident-specific information */
 436                 u32 isinfo[28];
 437         } __attribute__ ((packed)) *lir;
 438
 439         lir = data;
 440         if (!(lir->iq&0x80))
 441                 /* NULL link incident record */
 442                 return -EINVAL;
 443         if (!(lir->indesc[0]&0xc0000000))
 444                 /* node descriptor not valid */
 445                 return -EINVAL;
 446         if (!(lir->indesc[0]&0x10000000))
 447                 /* don't handle device-type nodes - FIXME */
 448                 return -EINVAL;
 449         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
 450
 451         return (u16) (lir->indesc[0]&0x000000ff);
 452 }
 453
 454 struct chsc_sei_area {
 455         struct chsc_header request;
 456         u32 reserved1;
 457         u32 reserved2;
 458         u32 reserved3;
 459         struct chsc_header response;
 460         u32 reserved4;
 461         u8  flags;
 462         u8  vf;         /* validity flags */
 463         u8  rs;         /* reporting source */
 464         u8  cc;         /* content code */
 465         u16 fla;        /* full link address */
 466         u16 rsid;       /* reporting source id */
 467         u32 reserved5;
 468         u32 reserved6;
 469         u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
 470         /* ccdf has to be big enough for a link-incident record */
 471 } __attribute__ ((packed));
 472
 473 static int chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
 474 {
 475         struct chp_id chpid;
 476         int id;
 477
 478         CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
 479                       sei_area->rs, sei_area->rsid);
 480         if (sei_area->rs != 4)
 481                 return 0;
 482         id = __get_chpid_from_lir(sei_area->ccdf);
 483         if (id < 0)
 484                 CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
 485         else {
 486                 chp_id_init(&chpid);
 487                 chpid.id = id;
 488                 chsc_chp_offline(chpid);
 489         }
 490
 491         return 0;
 492 }
 493
 494 static int chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
 495 {
 496         struct res_acc_data res_data;
 497         struct chp_id chpid;
 498         int status;
 499         int rc;
 500
 501         CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
 502                       "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
 503         if (sei_area->rs != 4)
 504                 return 0;
 505         chp_id_init(&chpid);
 506         chpid.id = sei_area->rsid;
 507         /* allocate a new channel path structure, if needed */
 508         status = chp_get_status(chpid);
 509         if (status < 0)
 510                 chp_new(chpid);
 511         else if (!status)
 512                 return 0;
 513         memset(&res_data, 0, sizeof(struct res_acc_data));
 514         res_data.chpid = chpid;
 515         if ((sei_area->vf & 0xc0) != 0) {
 516                 res_data.fla = sei_area->fla;
 517                 if ((sei_area->vf & 0xc0) == 0xc0)
 518                         /* full link address */
 519                         res_data.fla_mask = 0xffff;
 520                 else
 521                         /* link address */
 522                         res_data.fla_mask = 0xff00;
 523         }
 524         rc = s390_process_res_acc(&res_data);
 525
 526         return rc;
 527 }
 528
 529 struct chp_config_data {
 530         u8 map[32];
 531         u8 op;
 532         u8 pc;
 533 };
 534
 535 static int chsc_process_sei_chp_config(struct chsc_sei_area *sei_area)
 536 {
 537         struct chp_config_data *data;
 538         struct chp_id chpid;
 539         int num;
 540
 541         CIO_CRW_EVENT(4, "chsc: channel-path-configuration notification\n");
 542         if (sei_area->rs != 0)
 543                 return 0;
 544         data = (struct chp_config_data *) &(sei_area->ccdf);
 545         chp_id_init(&chpid);
 546         for (num = 0; num <= __MAX_CHPID; num++) {
 547                 if (!chp_test_bit(data->map, num))
 548                         continue;
 549                 chpid.id = num;
 550                 printk(KERN_WARNING "cio: processing configure event %d for "
 551                        "chpid %x.%02x\n", data->op, chpid.cssid, chpid.id);
 552                 switch (data->op) {
 553                 case 0:
 554                         chp_cfg_schedule(chpid, 1);
 555                         break;
 556                 case 1:
 557                         chp_cfg_schedule(chpid, 0);
 558                         break;
 559                 case 2:
 560                         chp_cfg_cancel_deconfigure(chpid);
 561                         break;
 562                 }
 563         }
 564
 565         return 0;
 566 }
 567
 568 static int chsc_process_sei(struct chsc_sei_area *sei_area)
 569 {
 570         int rc;
 571
 572         /* Check if we might have lost some information. */
 573         if (sei_area->flags & 0x40)
 574                 CIO_CRW_EVENT(2, "chsc: event overflow\n");
 575         /* which kind of information was stored? */
 576         rc = 0;
 577         switch (sei_area->cc) {
 578         case 1: /* link incident*/
 579                 rc = chsc_process_sei_link_incident(sei_area);
 580                 break;
 581         case 2: /* i/o resource accessibiliy */
 582                 rc = chsc_process_sei_res_acc(sei_area);
 583                 break;
 584         case 8: /* channel-path-configuration notification */
 585                 rc = chsc_process_sei_chp_config(sei_area);
 586                 break;
 587         default: /* other stuff */
 588                 CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
 589                               sei_area->cc);
 590                 break;
 591         }
 592
 593         return rc;
 594 }
 595
 596 int chsc_process_crw(void)
 597 {
 598         struct chsc_sei_area *sei_area;
 599         int ret;
 600         int rc;
 601
 602         if (!sei_page)
 603                 return 0;
 604         /* Access to sei_page is serialized through machine check handler
 605          * thread, so no need for locking. */
 606         sei_area = sei_page;
 607
 608         CIO_TRACE_EVENT( 2, "prcss");
 609         ret = 0;
 610         do {
 611                 memset(sei_area, 0, sizeof(*sei_area));
 612                 sei_area->request.length = 0x0010;
 613                 sei_area->request.code = 0x000e;
 614                 if (chsc(sei_area))
 615                         break;
 616
 617                 if (sei_area->response.code == 0x0001) {
 618                         CIO_CRW_EVENT(4, "chsc: sei successful\n");
 619                         rc = chsc_process_sei(sei_area);
 620                         if (rc)
 621                                 ret = rc;
 622                 } else {
 623                         CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
 624                                       sei_area->response.code);
 625                         ret = 0;
 626                         break;
 627                 }
 628         } while (sei_area->flags & 0x80);
 629
 630         return ret;
 631 }
 632
 633 static int
 634 __chp_add_new_sch(struct subchannel_id schid)
 635 {
 636         struct schib schib;
 637         int ret;
 638
 639         if (stsch_err(schid, &schib))
 640                 /* We're through */
 641                 return need_rescan ? -EAGAIN : -ENXIO;
 642
 643         /* Put it on the slow path. */
 644         ret = css_enqueue_subchannel_slow(schid);
 645         if (ret) {
 646                 css_clear_subchannel_slow_list();
 647                 need_rescan = 1;
 648                 return -EAGAIN;
 649         }
 650         return 0;
 651 }
 652
 653
 654 static int
 655 __chp_add(struct subchannel_id schid, void *data)
 656 {
 657         int i, mask;
 658         struct chp_id *chpid;
 659         struct subchannel *sch;
 660
 661         chpid = data;
 662         sch = get_subchannel_by_schid(schid);
 663         if (!sch)
 664                 /* Check if the subchannel is now available. */
 665                 return __chp_add_new_sch(schid);
 666         spin_lock_irq(sch->lock);
 667         for (i=0; i<8; i++) {
 668                 mask = 0x80 >> i;
 669                 if ((sch->schib.pmcw.pim & mask) &&
 670                     (sch->schib.pmcw.chpid[i] == chpid->id)) {
 671                         if (stsch(sch->schid, &sch->schib) != 0) {
 672                                 /* Endgame. */
 673                                 spin_unlock_irq(sch->lock);
 674                                 return -ENXIO;
 675                         }
 676                         break;
 677                 }
 678         }
 679         if (i==8) {
 680                 spin_unlock_irq(sch->lock);
 681                 return 0;
 682         }
 683         sch->lpm = ((sch->schib.pmcw.pim &
 684                      sch->schib.pmcw.pam &
 685                      sch->schib.pmcw.pom)
 686                     | mask) & sch->opm;
 687
 688         if (sch->driver && sch->driver->verify)
 689                 sch->driver->verify(&sch->dev);
 690
 691         spin_unlock_irq(sch->lock);
 692         put_device(&sch->dev);
 693         return 0;
 694 }
 695
 696 int chsc_chp_online(struct chp_id chpid)
 697 {
 698         int rc;
 699         char dbf_txt[15];
 700
 701         sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
 702         CIO_TRACE_EVENT(2, dbf_txt);
 703
 704         if (chp_get_status(chpid) == 0)
 705                 return 0;
 706         rc = for_each_subchannel(__chp_add, &chpid);
 707         if (css_slow_subchannels_exist())
 708                 rc = -EAGAIN;
 709         if (rc != -EAGAIN)
 710                 rc = 0;
 711         return rc;
 712 }
 713
 714 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
 715                                          struct chp_id chpid, int on)
 716 {
 717         int chp, old_lpm;
 718         unsigned long flags;
 719
 720         if (!sch->ssd_info.valid)
 721                 return;
 722
 723         spin_lock_irqsave(sch->lock, flags);
 724         old_lpm = sch->lpm;
 725         for (chp = 0; chp < 8; chp++) {
 726                 if (sch->ssd_info.chpid[chp] != chpid.id)
 727                         continue;
 728
 729                 if (on) {
 730                         sch->opm |= (0x80 >> chp);
 731                         sch->lpm |= (0x80 >> chp);
 732                         if (!old_lpm)
 733                                 device_trigger_reprobe(sch);
 734                         else if (sch->driver && sch->driver->verify)
 735                                 sch->driver->verify(&sch->dev);
 736                         break;
 737                 }
 738                 sch->opm &= ~(0x80 >> chp);
 739                 sch->lpm &= ~(0x80 >> chp);
 740                 if (check_for_io_on_path(sch, (0x80 >> chp))) {
 741                         if (device_is_online(sch))
 742                                 /* Path verification is done after killing. */
 743                                 device_kill_io(sch);
 744                         else {
 745                                 /* Kill and retry internal I/O. */
 746                                 terminate_internal_io(sch);
 747                                 /* Re-start path verification. */
 748                                 if (sch->driver && sch->driver->verify)
 749                                         sch->driver->verify(&sch->dev);
 750                         }
 751                 } else if (!sch->lpm) {
 752                         if (device_trigger_verify(sch) != 0) {
 753                                 if (css_enqueue_subchannel_slow(sch->schid)) {
 754                                         css_clear_subchannel_slow_list();
 755                                         need_rescan = 1;
 756                                 }
 757                         }
 758                 } else if (sch->driver && sch->driver->verify)
 759                         sch->driver->verify(&sch->dev);
 760                 break;
 761         }
 762         spin_unlock_irqrestore(sch->lock, flags);
 763 }
 764
 765 static int s390_subchannel_vary_chpid_off(struct device *dev, void *data)
 766 {
 767         struct subchannel *sch;
 768         struct chp_id *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 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
 778 {
 779         struct subchannel *sch;
 780         struct chp_id *chpid;
 781
 782         sch = to_subchannel(dev);
 783         chpid = data;
 784
 785         __s390_subchannel_vary_chpid(sch, *chpid, 1);
 786         return 0;
 787 }
 788
 789 static int
 790 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
 791 {
 792         struct schib schib;
 793         struct subchannel *sch;
 794
 795         sch = get_subchannel_by_schid(schid);
 796         if (sch) {
 797                 put_device(&sch->dev);
 798                 return 0;
 799         }
 800         if (stsch_err(schid, &schib))
 801                 /* We're through */
 802                 return -ENXIO;
 803         /* Put it on the slow path. */
 804         if (css_enqueue_subchannel_slow(schid)) {
 805                 css_clear_subchannel_slow_list();
 806                 need_rescan = 1;
 807                 return -EAGAIN;
 808         }
 809         return 0;
 810 }
 811
 812 /**
 813  * chsc_chp_vary - propagate channel-path vary operation to subchannels
 814  * @chpid: channl-path ID
 815  * @on: non-zero for vary online, zero for vary offline
 816  */
 817 int chsc_chp_vary(struct chp_id chpid, int on)
 818 {
 819         /*
 820          * Redo PathVerification on the devices the chpid connects to
 821          */
 822
 823         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
 824                          s390_subchannel_vary_chpid_on :
 825                          s390_subchannel_vary_chpid_off);
 826         if (on)
 827                 /* Scan for new devices on varied on path. */
 828                 for_each_subchannel(__s390_vary_chpid_on, NULL);
 829         if (need_rescan || css_slow_subchannels_exist())
 830                 queue_work(slow_path_wq, &slow_path_work);
 831         return 0;
 832 }
 833
 834 static void
 835 chsc_remove_cmg_attr(struct channel_subsystem *css)
 836 {
 837         int i;
 838
 839         for (i = 0; i <= __MAX_CHPID; i++) {
 840                 if (!css->chps[i])
 841                         continue;
 842                 chp_remove_cmg_attr(css->chps[i]);
 843         }
 844 }
 845
 846 static int
 847 chsc_add_cmg_attr(struct channel_subsystem *css)
 848 {
 849         int i, ret;
 850
 851         ret = 0;
 852         for (i = 0; i <= __MAX_CHPID; i++) {
 853                 if (!css->chps[i])
 854                         continue;
 855                 ret = chp_add_cmg_attr(css->chps[i]);
 856                 if (ret)
 857                         goto cleanup;
 858         }
 859         return ret;
 860 cleanup:
 861         for (--i; i >= 0; i--) {
 862                 if (!css->chps[i])
 863                         continue;
 864                 chp_remove_cmg_attr(css->chps[i]);
 865         }
 866         return ret;
 867 }
 868
 869 static int
 870 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
 871 {
 872         struct {
 873                 struct chsc_header request;
 874                 u32 operation_code : 2;
 875                 u32 : 30;
 876                 u32 key : 4;
 877                 u32 : 28;
 878                 u32 zeroes1;
 879                 u32 cub_addr1;
 880                 u32 zeroes2;
 881                 u32 cub_addr2;
 882                 u32 reserved[13];
 883                 struct chsc_header response;
 884                 u32 status : 8;
 885                 u32 : 4;
 886                 u32 fmt : 4;
 887                 u32 : 16;
 888         } __attribute__ ((packed)) *secm_area;
 889         int ret, ccode;
 890
 891         secm_area = page;
 892         secm_area->request.length = 0x0050;
 893         secm_area->request.code = 0x0016;
 894
 895         secm_area->key = PAGE_DEFAULT_KEY;
 896         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
 897         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
 898
 899         secm_area->operation_code = enable ? 0 : 1;
 900
 901         ccode = chsc(secm_area);
 902         if (ccode > 0)
 903                 return (ccode == 3) ? -ENODEV : -EBUSY;
 904
 905         switch (secm_area->response.code) {
 906         case 0x0001: /* Success. */
 907                 ret = 0;
 908                 break;
 909         case 0x0003: /* Invalid block. */
 910         case 0x0007: /* Invalid format. */
 911         case 0x0008: /* Other invalid block. */
 912                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
 913                 ret = -EINVAL;
 914                 break;
 915         case 0x0004: /* Command not provided in model. */
 916                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
 917                 ret = -EOPNOTSUPP;
 918                 break;
 919         case 0x0102: /* cub adresses incorrect */
 920                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
 921                 ret = -EINVAL;
 922                 break;
 923         case 0x0103: /* key error */
 924                 CIO_CRW_EVENT(2, "Access key error in secm\n");
 925                 ret = -EINVAL;
 926                 break;
 927         case 0x0105: /* error while starting */
 928                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
 929                 ret = -EIO;
 930                 break;
 931         default:
 932                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
 933                               secm_area->response.code);
 934                 ret = -EIO;
 935         }
 936         return ret;
 937 }
 938
 939 int
 940 chsc_secm(struct channel_subsystem *css, int enable)
 941 {
 942         void  *secm_area;
 943         int ret;
 944
 945         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
 946         if (!secm_area)
 947                 return -ENOMEM;
 948
 949         mutex_lock(&css->mutex);
 950         if (enable && !css->cm_enabled) {
 951                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 952                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
 953                 if (!css->cub_addr1 || !css->cub_addr2) {
 954                         free_page((unsigned long)css->cub_addr1);
 955                         free_page((unsigned long)css->cub_addr2);
 956                         free_page((unsigned long)secm_area);
 957                         mutex_unlock(&css->mutex);
 958                         return -ENOMEM;
 959                 }
 960         }
 961         ret = __chsc_do_secm(css, enable, secm_area);
 962         if (!ret) {
 963                 css->cm_enabled = enable;
 964                 if (css->cm_enabled) {
 965                         ret = chsc_add_cmg_attr(css);
 966                         if (ret) {
 967                                 memset(secm_area, 0, PAGE_SIZE);
 968                                 __chsc_do_secm(css, 0, secm_area);
 969                                 css->cm_enabled = 0;
 970                         }
 971                 } else
 972                         chsc_remove_cmg_attr(css);
 973         }
 974         if (enable && !css->cm_enabled) {
 975                 free_page((unsigned long)css->cub_addr1);
 976                 free_page((unsigned long)css->cub_addr2);
 977         }
 978         mutex_unlock(&css->mutex);
 979         free_page((unsigned long)secm_area);
 980         return ret;
 981 }
 982
 983 int chsc_determine_channel_path_description(struct chp_id chpid,
 984                                             struct channel_path_desc *desc)
 985 {
 986         int ccode, ret;
 987
 988         struct {
 989                 struct chsc_header request;
 990                 u32 : 24;
 991                 u32 first_chpid : 8;
 992                 u32 : 24;
 993                 u32 last_chpid : 8;
 994                 u32 zeroes1;
 995                 struct chsc_header response;
 996                 u32 zeroes2;
 997                 struct channel_path_desc desc;
 998         } __attribute__ ((packed)) *scpd_area;
 999
1000         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1001         if (!scpd_area)
1002                 return -ENOMEM;
1003
1004         scpd_area->request.length = 0x0010;
1005         scpd_area->request.code = 0x0002;
1006
1007         scpd_area->first_chpid = chpid.id;
1008         scpd_area->last_chpid = chpid.id;
1009
1010         ccode = chsc(scpd_area);
1011         if (ccode > 0) {
1012                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1013                 goto out;
1014         }
1015
1016         switch (scpd_area->response.code) {
1017         case 0x0001: /* Success. */
1018                 memcpy(desc, &scpd_area->desc,
1019                        sizeof(struct channel_path_desc));
1020                 ret = 0;
1021                 break;
1022         case 0x0003: /* Invalid block. */
1023         case 0x0007: /* Invalid format. */
1024         case 0x0008: /* Other invalid block. */
1025                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1026                 ret = -EINVAL;
1027                 break;
1028         case 0x0004: /* Command not provided in model. */
1029                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
1030                 ret = -EOPNOTSUPP;
1031                 break;
1032         default:
1033                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1034                               scpd_area->response.code);
1035                 ret = -EIO;
1036         }
1037 out:
1038         free_page((unsigned long)scpd_area);
1039         return ret;
1040 }
1041
1042 static void
1043 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1044                           struct cmg_chars *chars)
1045 {
1046         switch (chp->cmg) {
1047         case 2:
1048         case 3:
1049                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1050                                          GFP_KERNEL);
1051                 if (chp->cmg_chars) {
1052                         int i, mask;
1053                         struct cmg_chars *cmg_chars;
1054
1055                         cmg_chars = chp->cmg_chars;
1056                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1057                                 mask = 0x80 >> (i + 3);
1058                                 if (cmcv & mask)
1059                                         cmg_chars->values[i] = chars->values[i];
1060                                 else
1061                                         cmg_chars->values[i] = 0;
1062                         }
1063                 }
1064                 break;
1065         default:
1066                 /* No cmg-dependent data. */
1067                 break;
1068         }
1069 }
1070
1071 int chsc_get_channel_measurement_chars(struct channel_path *chp)
1072 {
1073         int ccode, ret;
1074
1075         struct {
1076                 struct chsc_header request;
1077                 u32 : 24;
1078                 u32 first_chpid : 8;
1079                 u32 : 24;
1080                 u32 last_chpid : 8;
1081                 u32 zeroes1;
1082                 struct chsc_header response;
1083                 u32 zeroes2;
1084                 u32 not_valid : 1;
1085                 u32 shared : 1;
1086                 u32 : 22;
1087                 u32 chpid : 8;
1088                 u32 cmcv : 5;
1089                 u32 : 11;
1090                 u32 cmgq : 8;
1091                 u32 cmg : 8;
1092                 u32 zeroes3;
1093                 u32 data[NR_MEASUREMENT_CHARS];
1094         } __attribute__ ((packed)) *scmc_area;
1095
1096         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1097         if (!scmc_area)
1098                 return -ENOMEM;
1099
1100         scmc_area->request.length = 0x0010;
1101         scmc_area->request.code = 0x0022;
1102
1103         scmc_area->first_chpid = chp->chpid.id;
1104         scmc_area->last_chpid = chp->chpid.id;
1105
1106         ccode = chsc(scmc_area);
1107         if (ccode > 0) {
1108                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1109                 goto out;
1110         }
1111
1112         switch (scmc_area->response.code) {
1113         case 0x0001: /* Success. */
1114                 if (!scmc_area->not_valid) {
1115                         chp->cmg = scmc_area->cmg;
1116                         chp->shared = scmc_area->shared;
1117                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1118                                                   (struct cmg_chars *)
1119                                                   &scmc_area->data);
1120                 } else {
1121                         chp->cmg = -1;
1122                         chp->shared = -1;
1123                 }
1124                 ret = 0;
1125                 break;
1126         case 0x0003: /* Invalid block. */
1127         case 0x0007: /* Invalid format. */
1128         case 0x0008: /* Invalid bit combination. */
1129                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1130                 ret = -EINVAL;
1131                 break;
1132         case 0x0004: /* Command not provided. */
1133                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1134                 ret = -EOPNOTSUPP;
1135                 break;
1136         default:
1137                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1138                               scmc_area->response.code);
1139                 ret = -EIO;
1140         }
1141 out:
1142         free_page((unsigned long)scmc_area);
1143         return ret;
1144 }
1145
1146 static int __init
1147 chsc_alloc_sei_area(void)
1148 {
1149         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1150         if (!sei_page)
1151                 printk(KERN_WARNING"Can't allocate page for processing of " \
1152                        "chsc machine checks!\n");
1153         return (sei_page ? 0 : -ENOMEM);
1154 }
1155
1156 int __init
1157 chsc_enable_facility(int operation_code)
1158 {
1159         int ret;
1160         struct {
1161                 struct chsc_header request;
1162                 u8 reserved1:4;
1163                 u8 format:4;
1164                 u8 reserved2;
1165                 u16 operation_code;
1166                 u32 reserved3;
1167                 u32 reserved4;
1168                 u32 operation_data_area[252];
1169                 struct chsc_header response;
1170                 u32 reserved5:4;
1171                 u32 format2:4;
1172                 u32 reserved6:24;
1173         } __attribute__ ((packed)) *sda_area;
1174
1175         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1176         if (!sda_area)
1177                 return -ENOMEM;
1178         sda_area->request.length = 0x0400;
1179         sda_area->request.code = 0x0031;
1180         sda_area->operation_code = operation_code;
1181
1182         ret = chsc(sda_area);
1183         if (ret > 0) {
1184                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1185                 goto out;
1186         }
1187         switch (sda_area->response.code) {
1188         case 0x0001: /* everything ok */
1189                 ret = 0;
1190                 break;
1191         case 0x0003: /* invalid request block */
1192         case 0x0007:
1193                 ret = -EINVAL;
1194                 break;
1195         case 0x0004: /* command not provided */
1196         case 0x0101: /* facility not provided */
1197                 ret = -EOPNOTSUPP;
1198                 break;
1199         default: /* something went wrong */
1200                 ret = -EIO;
1201         }
1202  out:
1203         free_page((unsigned long)sda_area);
1204         return ret;
1205 }
1206
1207 subsys_initcall(chsc_alloc_sei_area);
1208
1209 struct css_general_char css_general_characteristics;
1210 struct css_chsc_char css_chsc_characteristics;
1211
1212 int __init
1213 chsc_determine_css_characteristics(void)
1214 {
1215         int result;
1216         struct {
1217                 struct chsc_header request;
1218                 u32 reserved1;
1219                 u32 reserved2;
1220                 u32 reserved3;
1221                 struct chsc_header response;
1222                 u32 reserved4;
1223                 u32 general_char[510];
1224                 u32 chsc_char[518];
1225         } __attribute__ ((packed)) *scsc_area;
1226
1227         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1228         if (!scsc_area) {
1229                 printk(KERN_WARNING"cio: Was not able to determine available" \
1230                        "CHSCs due to no memory.\n");
1231                 return -ENOMEM;
1232         }
1233
1234         scsc_area->request.length = 0x0010;
1235         scsc_area->request.code = 0x0010;
1236
1237         result = chsc(scsc_area);
1238         if (result) {
1239                 printk(KERN_WARNING"cio: Was not able to determine " \
1240                        "available CHSCs, cc=%i.\n", result);
1241                 result = -EIO;
1242                 goto exit;
1243         }
1244
1245         if (scsc_area->response.code != 1) {
1246                 printk(KERN_WARNING"cio: Was not able to determine " \
1247                        "available CHSCs.\n");
1248                 result = -EIO;
1249                 goto exit;
1250         }
1251         memcpy(&css_general_characteristics, scsc_area->general_char,
1252                sizeof(css_general_characteristics));
1253         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1254                sizeof(css_chsc_characteristics));
1255 exit:
1256         free_page ((unsigned long) scsc_area);
1257         return result;
1258 }
1259
1260 EXPORT_SYMBOL_GPL(css_general_characteristics);
1261 EXPORT_SYMBOL_GPL(css_chsc_characteristics);