drivers/s390/char/sclp_cmd.c

   1 /*
   2  * Copyright IBM Corp. 2007, 2009
   3  *
   4  * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
   5  *            Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
   6  */
   7
   8 #define KMSG_COMPONENT "sclp_cmd"
   9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  10
  11 #include <linux/completion.h>
  12 #include <linux/init.h>
  13 #include <linux/errno.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/string.h>
  17 #include <linux/mm.h>
  18 #include <linux/mmzone.h>
  19 #include <linux/memory.h>
  20 #include <linux/platform_device.h>
  21 #include <asm/chpid.h>
  22 #include <asm/sclp.h>
  23 #include <asm/setup.h>
  24
  25 #include "sclp.h"
  26
  27 #define SCLP_CMDW_READ_SCP_INFO         0x00020001
  28 #define SCLP_CMDW_READ_SCP_INFO_FORCED  0x00120001
  29
  30 struct read_info_sccb {
  31         struct  sccb_header header;     /* 0-7 */
  32         u16     rnmax;                  /* 8-9 */
  33         u8      rnsize;                 /* 10 */
  34         u8      _reserved0[24 - 11];    /* 11-15 */
  35         u8      loadparm[8];            /* 24-31 */
  36         u8      _reserved1[48 - 32];    /* 32-47 */
  37         u64     facilities;             /* 48-55 */
  38         u8      _reserved2[84 - 56];    /* 56-83 */
  39         u8      fac84;                  /* 84 */
  40         u8      _reserved3[91 - 85];    /* 85-90 */
  41         u8      flags;                  /* 91 */
  42         u8      _reserved4[100 - 92];   /* 92-99 */
  43         u32     rnsize2;                /* 100-103 */
  44         u64     rnmax2;                 /* 104-111 */
  45         u8      _reserved5[4096 - 112]; /* 112-4095 */
  46 } __attribute__((packed, aligned(PAGE_SIZE)));
  47
  48 static struct read_info_sccb __initdata early_read_info_sccb;
  49 static int __initdata early_read_info_sccb_valid;
  50
  51 u64 sclp_facilities;
  52 static u8 sclp_fac84;
  53 static unsigned long long rzm;
  54 static unsigned long long rnmax;
  55
  56 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  57 {
  58         int rc;
  59
  60         __ctl_set_bit(0, 9);
  61         rc = sclp_service_call(cmd, sccb);
  62         if (rc)
  63                 goto out;
  64         __load_psw_mask(PSW_BASE_BITS | PSW_MASK_EXT |
  65                         PSW_MASK_WAIT | PSW_DEFAULT_KEY);
  66         local_irq_disable();
  67 out:
  68         /* Contents of the sccb might have changed. */
  69         barrier();
  70         __ctl_clear_bit(0, 9);
  71         return rc;
  72 }
  73
  74 static void __init sclp_read_info_early(void)
  75 {
  76         int rc;
  77         int i;
  78         struct read_info_sccb *sccb;
  79         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  80                                   SCLP_CMDW_READ_SCP_INFO};
  81
  82         sccb = &early_read_info_sccb;
  83         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  84                 do {
  85                         memset(sccb, 0, sizeof(*sccb));
  86                         sccb->header.length = sizeof(*sccb);
  87                         sccb->header.function_code = 0x80;
  88                         sccb->header.control_mask[2] = 0x80;
  89                         rc = sclp_cmd_sync_early(commands[i], sccb);
  90                 } while (rc == -EBUSY);
  91
  92                 if (rc)
  93                         break;
  94                 if (sccb->header.response_code == 0x10) {
  95                         early_read_info_sccb_valid = 1;
  96                         break;
  97                 }
  98                 if (sccb->header.response_code != 0x1f0)
  99                         break;
 100         }
 101 }
 102
 103 void __init sclp_facilities_detect(void)
 104 {
 105         struct read_info_sccb *sccb;
 106
 107         sclp_read_info_early();
 108         if (!early_read_info_sccb_valid)
 109                 return;
 110
 111         sccb = &early_read_info_sccb;
 112         sclp_facilities = sccb->facilities;
 113         sclp_fac84 = sccb->fac84;
 114         rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 115         rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 116         rzm <<= 20;
 117 }
 118
 119 unsigned long long sclp_get_rnmax(void)
 120 {
 121         return rnmax;
 122 }
 123
 124 unsigned long long sclp_get_rzm(void)
 125 {
 126         return rzm;
 127 }
 128
 129 /*
 130  * This function will be called after sclp_facilities_detect(), which gets
 131  * called from early.c code. Therefore the sccb should have valid contents.
 132  */
 133 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 134 {
 135         struct read_info_sccb *sccb;
 136
 137         if (!early_read_info_sccb_valid)
 138                 return;
 139         sccb = &early_read_info_sccb;
 140         info->is_valid = 1;
 141         if (sccb->flags & 0x2)
 142                 info->has_dump = 1;
 143         memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
 144 }
 145
 146 static void sclp_sync_callback(struct sclp_req *req, void *data)
 147 {
 148         struct completion *completion = data;
 149
 150         complete(completion);
 151 }
 152
 153 static int do_sync_request(sclp_cmdw_t cmd, void *sccb)
 154 {
 155         struct completion completion;
 156         struct sclp_req *request;
 157         int rc;
 158
 159         request = kzalloc(sizeof(*request), GFP_KERNEL);
 160         if (!request)
 161                 return -ENOMEM;
 162         request->command = cmd;
 163         request->sccb = sccb;
 164         request->status = SCLP_REQ_FILLED;
 165         request->callback = sclp_sync_callback;
 166         request->callback_data = &completion;
 167         init_completion(&completion);
 168
 169         /* Perform sclp request. */
 170         rc = sclp_add_request(request);
 171         if (rc)
 172                 goto out;
 173         wait_for_completion(&completion);
 174
 175         /* Check response. */
 176         if (request->status != SCLP_REQ_DONE) {
 177                 pr_warning("sync request failed (cmd=0x%08x, "
 178                            "status=0x%02x)\n", cmd, request->status);
 179                 rc = -EIO;
 180         }
 181 out:
 182         kfree(request);
 183         return rc;
 184 }
 185
 186 /*
 187  * CPU configuration related functions.
 188  */
 189
 190 #define SCLP_CMDW_READ_CPU_INFO         0x00010001
 191 #define SCLP_CMDW_CONFIGURE_CPU         0x00110001
 192 #define SCLP_CMDW_DECONFIGURE_CPU       0x00100001
 193
 194 struct read_cpu_info_sccb {
 195         struct  sccb_header header;
 196         u16     nr_configured;
 197         u16     offset_configured;
 198         u16     nr_standby;
 199         u16     offset_standby;
 200         u8      reserved[4096 - 16];
 201 } __attribute__((packed, aligned(PAGE_SIZE)));
 202
 203 static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
 204                                struct read_cpu_info_sccb *sccb)
 205 {
 206         char *page = (char *) sccb;
 207
 208         memset(info, 0, sizeof(*info));
 209         info->configured = sccb->nr_configured;
 210         info->standby = sccb->nr_standby;
 211         info->combined = sccb->nr_configured + sccb->nr_standby;
 212         info->has_cpu_type = sclp_fac84 & 0x1;
 213         memcpy(&info->cpu, page + sccb->offset_configured,
 214                info->combined * sizeof(struct sclp_cpu_entry));
 215 }
 216
 217 int sclp_get_cpu_info(struct sclp_cpu_info *info)
 218 {
 219         int rc;
 220         struct read_cpu_info_sccb *sccb;
 221
 222         if (!SCLP_HAS_CPU_INFO)
 223                 return -EOPNOTSUPP;
 224         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 225         if (!sccb)
 226                 return -ENOMEM;
 227         sccb->header.length = sizeof(*sccb);
 228         rc = do_sync_request(SCLP_CMDW_READ_CPU_INFO, sccb);
 229         if (rc)
 230                 goto out;
 231         if (sccb->header.response_code != 0x0010) {
 232                 pr_warning("readcpuinfo failed (response=0x%04x)\n",
 233                            sccb->header.response_code);
 234                 rc = -EIO;
 235                 goto out;
 236         }
 237         sclp_fill_cpu_info(info, sccb);
 238 out:
 239         free_page((unsigned long) sccb);
 240         return rc;
 241 }
 242
 243 struct cpu_configure_sccb {
 244         struct sccb_header header;
 245 } __attribute__((packed, aligned(8)));
 246
 247 static int do_cpu_configure(sclp_cmdw_t cmd)
 248 {
 249         struct cpu_configure_sccb *sccb;
 250         int rc;
 251
 252         if (!SCLP_HAS_CPU_RECONFIG)
 253                 return -EOPNOTSUPP;
 254         /*
 255          * This is not going to cross a page boundary since we force
 256          * kmalloc to have a minimum alignment of 8 bytes on s390.
 257          */
 258         sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
 259         if (!sccb)
 260                 return -ENOMEM;
 261         sccb->header.length = sizeof(*sccb);
 262         rc = do_sync_request(cmd, sccb);
 263         if (rc)
 264                 goto out;
 265         switch (sccb->header.response_code) {
 266         case 0x0020:
 267         case 0x0120:
 268                 break;
 269         default:
 270                 pr_warning("configure cpu failed (cmd=0x%08x, "
 271                            "response=0x%04x)\n", cmd,
 272                            sccb->header.response_code);
 273                 rc = -EIO;
 274                 break;
 275         }
 276 out:
 277         kfree(sccb);
 278         return rc;
 279 }
 280
 281 int sclp_cpu_configure(u8 cpu)
 282 {
 283         return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
 284 }
 285
 286 int sclp_cpu_deconfigure(u8 cpu)
 287 {
 288         return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
 289 }
 290
 291 #ifdef CONFIG_MEMORY_HOTPLUG
 292
 293 static DEFINE_MUTEX(sclp_mem_mutex);
 294 static LIST_HEAD(sclp_mem_list);
 295 static u8 sclp_max_storage_id;
 296 static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
 297 static int sclp_mem_state_changed;
 298
 299 struct memory_increment {
 300         struct list_head list;
 301         u16 rn;
 302         int standby;
 303         int usecount;
 304 };
 305
 306 struct assign_storage_sccb {
 307         struct sccb_header header;
 308         u16 rn;
 309 } __packed;
 310
 311 int arch_get_memory_phys_device(unsigned long start_pfn)
 312 {
 313         if (!rzm)
 314                 return 0;
 315         return PFN_PHYS(start_pfn) >> ilog2(rzm);
 316 }
 317
 318 static unsigned long long rn2addr(u16 rn)
 319 {
 320         return (unsigned long long) (rn - 1) * rzm;
 321 }
 322
 323 static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
 324 {
 325         struct assign_storage_sccb *sccb;
 326         int rc;
 327
 328         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 329         if (!sccb)
 330                 return -ENOMEM;
 331         sccb->header.length = PAGE_SIZE;
 332         sccb->rn = rn;
 333         rc = do_sync_request(cmd, sccb);
 334         if (rc)
 335                 goto out;
 336         switch (sccb->header.response_code) {
 337         case 0x0020:
 338         case 0x0120:
 339                 break;
 340         default:
 341                 pr_warning("assign storage failed (cmd=0x%08x, "
 342                            "response=0x%04x, rn=0x%04x)\n", cmd,
 343                            sccb->header.response_code, rn);
 344                 rc = -EIO;
 345                 break;
 346         }
 347 out:
 348         free_page((unsigned long) sccb);
 349         return rc;
 350 }
 351
 352 static int sclp_assign_storage(u16 rn)
 353 {
 354         return do_assign_storage(0x000d0001, rn);
 355 }
 356
 357 static int sclp_unassign_storage(u16 rn)
 358 {
 359         return do_assign_storage(0x000c0001, rn);
 360 }
 361
 362 struct attach_storage_sccb {
 363         struct sccb_header header;
 364         u16 :16;
 365         u16 assigned;
 366         u32 :32;
 367         u32 entries[0];
 368 } __packed;
 369
 370 static int sclp_attach_storage(u8 id)
 371 {
 372         struct attach_storage_sccb *sccb;
 373         int rc;
 374         int i;
 375
 376         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 377         if (!sccb)
 378                 return -ENOMEM;
 379         sccb->header.length = PAGE_SIZE;
 380         rc = do_sync_request(0x00080001 | id << 8, sccb);
 381         if (rc)
 382                 goto out;
 383         switch (sccb->header.response_code) {
 384         case 0x0020:
 385                 set_bit(id, sclp_storage_ids);
 386                 for (i = 0; i < sccb->assigned; i++) {
 387                         if (sccb->entries[i])
 388                                 sclp_unassign_storage(sccb->entries[i] >> 16);
 389                 }
 390                 break;
 391         default:
 392                 rc = -EIO;
 393                 break;
 394         }
 395 out:
 396         free_page((unsigned long) sccb);
 397         return rc;
 398 }
 399
 400 static int sclp_mem_change_state(unsigned long start, unsigned long size,
 401                                  int online)
 402 {
 403         struct memory_increment *incr;
 404         unsigned long long istart;
 405         int rc = 0;
 406
 407         list_for_each_entry(incr, &sclp_mem_list, list) {
 408                 istart = rn2addr(incr->rn);
 409                 if (start + size - 1 < istart)
 410                         break;
 411                 if (start > istart + rzm - 1)
 412                         continue;
 413                 if (online) {
 414                         if (incr->usecount++)
 415                                 continue;
 416                         /*
 417                          * Don't break the loop if one assign fails. Loop may
 418                          * be walked again on CANCEL and we can't save
 419                          * information if state changed before or not.
 420                          * So continue and increase usecount for all increments.
 421                          */
 422                         rc |= sclp_assign_storage(incr->rn);
 423                 } else {
 424                         if (--incr->usecount)
 425                                 continue;
 426                         sclp_unassign_storage(incr->rn);
 427                 }
 428         }
 429         return rc ? -EIO : 0;
 430 }
 431
 432 static int sclp_mem_notifier(struct notifier_block *nb,
 433                              unsigned long action, void *data)
 434 {
 435         unsigned long start, size;
 436         struct memory_notify *arg;
 437         unsigned char id;
 438         int rc = 0;
 439
 440         arg = data;
 441         start = arg->start_pfn << PAGE_SHIFT;
 442         size = arg->nr_pages << PAGE_SHIFT;
 443         mutex_lock(&sclp_mem_mutex);
 444         for (id = 0; id <= sclp_max_storage_id; id++)
 445                 if (!test_bit(id, sclp_storage_ids))
 446                         sclp_attach_storage(id);
 447         switch (action) {
 448         case MEM_ONLINE:
 449         case MEM_GOING_OFFLINE:
 450         case MEM_CANCEL_OFFLINE:
 451                 break;
 452         case MEM_GOING_ONLINE:
 453                 rc = sclp_mem_change_state(start, size, 1);
 454                 break;
 455         case MEM_CANCEL_ONLINE:
 456                 sclp_mem_change_state(start, size, 0);
 457                 break;
 458         case MEM_OFFLINE:
 459                 sclp_mem_change_state(start, size, 0);
 460                 break;
 461         default:
 462                 rc = -EINVAL;
 463                 break;
 464         }
 465         if (!rc)
 466                 sclp_mem_state_changed = 1;
 467         mutex_unlock(&sclp_mem_mutex);
 468         return rc ? NOTIFY_BAD : NOTIFY_OK;
 469 }
 470
 471 static struct notifier_block sclp_mem_nb = {
 472         .notifier_call = sclp_mem_notifier,
 473 };
 474
 475 static void __init add_memory_merged(u16 rn)
 476 {
 477         static u16 first_rn, num;
 478         unsigned long long start, size;
 479
 480         if (rn && first_rn && (first_rn + num == rn)) {
 481                 num++;
 482                 return;
 483         }
 484         if (!first_rn)
 485                 goto skip_add;
 486         start = rn2addr(first_rn);
 487         size = (unsigned long long ) num * rzm;
 488         if (start >= VMEM_MAX_PHYS)
 489                 goto skip_add;
 490         if (start + size > VMEM_MAX_PHYS)
 491                 size = VMEM_MAX_PHYS - start;
 492         if (memory_end_set && (start >= memory_end))
 493                 goto skip_add;
 494         if (memory_end_set && (start + size > memory_end))
 495                 size = memory_end - start;
 496         add_memory(0, start, size);
 497 skip_add:
 498         first_rn = rn;
 499         num = 1;
 500 }
 501
 502 static void __init sclp_add_standby_memory(void)
 503 {
 504         struct memory_increment *incr;
 505
 506         list_for_each_entry(incr, &sclp_mem_list, list)
 507                 if (incr->standby)
 508                         add_memory_merged(incr->rn);
 509         add_memory_merged(0);
 510 }
 511
 512 static void __init insert_increment(u16 rn, int standby, int assigned)
 513 {
 514         struct memory_increment *incr, *new_incr;
 515         struct list_head *prev;
 516         u16 last_rn;
 517
 518         new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
 519         if (!new_incr)
 520                 return;
 521         new_incr->rn = rn;
 522         new_incr->standby = standby;
 523         if (!standby)
 524                 new_incr->usecount = 1;
 525         last_rn = 0;
 526         prev = &sclp_mem_list;
 527         list_for_each_entry(incr, &sclp_mem_list, list) {
 528                 if (assigned && incr->rn > rn)
 529                         break;
 530                 if (!assigned && incr->rn - last_rn > 1)
 531                         break;
 532                 last_rn = incr->rn;
 533                 prev = &incr->list;
 534         }
 535         if (!assigned)
 536                 new_incr->rn = last_rn + 1;
 537         if (new_incr->rn > rnmax) {
 538                 kfree(new_incr);
 539                 return;
 540         }
 541         list_add(&new_incr->list, prev);
 542 }
 543
 544 static int sclp_mem_freeze(struct device *dev)
 545 {
 546         if (!sclp_mem_state_changed)
 547                 return 0;
 548         pr_err("Memory hotplug state changed, suspend refused.\n");
 549         return -EPERM;
 550 }
 551
 552 struct read_storage_sccb {
 553         struct sccb_header header;
 554         u16 max_id;
 555         u16 assigned;
 556         u16 standby;
 557         u16 :16;
 558         u32 entries[0];
 559 } __packed;
 560
 561 static const struct dev_pm_ops sclp_mem_pm_ops = {
 562         .freeze         = sclp_mem_freeze,
 563 };
 564
 565 static struct platform_driver sclp_mem_pdrv = {
 566         .driver = {
 567                 .name   = "sclp_mem",
 568                 .pm     = &sclp_mem_pm_ops,
 569         },
 570 };
 571
 572 static int __init sclp_detect_standby_memory(void)
 573 {
 574         struct platform_device *sclp_pdev;
 575         struct read_storage_sccb *sccb;
 576         int i, id, assigned, rc;
 577
 578         if (!early_read_info_sccb_valid)
 579                 return 0;
 580         if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
 581                 return 0;
 582         rc = -ENOMEM;
 583         sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
 584         if (!sccb)
 585                 goto out;
 586         assigned = 0;
 587         for (id = 0; id <= sclp_max_storage_id; id++) {
 588                 memset(sccb, 0, PAGE_SIZE);
 589                 sccb->header.length = PAGE_SIZE;
 590                 rc = do_sync_request(0x00040001 | id << 8, sccb);
 591                 if (rc)
 592                         goto out;
 593                 switch (sccb->header.response_code) {
 594                 case 0x0010:
 595                         set_bit(id, sclp_storage_ids);
 596                         for (i = 0; i < sccb->assigned; i++) {
 597                                 if (!sccb->entries[i])
 598                                         continue;
 599                                 assigned++;
 600                                 insert_increment(sccb->entries[i] >> 16, 0, 1);
 601                         }
 602                         break;
 603                 case 0x0310:
 604                         break;
 605                 case 0x0410:
 606                         for (i = 0; i < sccb->assigned; i++) {
 607                                 if (!sccb->entries[i])
 608                                         continue;
 609                                 assigned++;
 610                                 insert_increment(sccb->entries[i] >> 16, 1, 1);
 611                         }
 612                         break;
 613                 default:
 614                         rc = -EIO;
 615                         break;
 616                 }
 617                 if (!rc)
 618                         sclp_max_storage_id = sccb->max_id;
 619         }
 620         if (rc || list_empty(&sclp_mem_list))
 621                 goto out;
 622         for (i = 1; i <= rnmax - assigned; i++)
 623                 insert_increment(0, 1, 0);
 624         rc = register_memory_notifier(&sclp_mem_nb);
 625         if (rc)
 626                 goto out;
 627         rc = platform_driver_register(&sclp_mem_pdrv);
 628         if (rc)
 629                 goto out;
 630         sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
 631         rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
 632         if (rc)
 633                 goto out_driver;
 634         sclp_add_standby_memory();
 635         goto out;
 636 out_driver:
 637         platform_driver_unregister(&sclp_mem_pdrv);
 638 out:
 639         free_page((unsigned long) sccb);
 640         return rc;
 641 }
 642 __initcall(sclp_detect_standby_memory);
 643
 644 #endif /* CONFIG_MEMORY_HOTPLUG */
 645
 646 /*
 647  * Channel path configuration related functions.
 648  */
 649
 650 #define SCLP_CMDW_CONFIGURE_CHPATH              0x000f0001
 651 #define SCLP_CMDW_DECONFIGURE_CHPATH            0x000e0001
 652 #define SCLP_CMDW_READ_CHPATH_INFORMATION       0x00030001
 653
 654 struct chp_cfg_sccb {
 655         struct sccb_header header;
 656         u8 ccm;
 657         u8 reserved[6];
 658         u8 cssid;
 659 } __attribute__((packed));
 660
 661 static int do_chp_configure(sclp_cmdw_t cmd)
 662 {
 663         struct chp_cfg_sccb *sccb;
 664         int rc;
 665
 666         if (!SCLP_HAS_CHP_RECONFIG)
 667                 return -EOPNOTSUPP;
 668         /* Prepare sccb. */
 669         sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 670         if (!sccb)
 671                 return -ENOMEM;
 672         sccb->header.length = sizeof(*sccb);
 673         rc = do_sync_request(cmd, sccb);
 674         if (rc)
 675                 goto out;
 676         switch (sccb->header.response_code) {
 677         case 0x0020:
 678         case 0x0120:
 679         case 0x0440:
 680         case 0x0450:
 681                 break;
 682         default:
 683                 pr_warning("configure channel-path failed "
 684                            "(cmd=0x%08x, response=0x%04x)\n", cmd,
 685                            sccb->header.response_code);
 686                 rc = -EIO;
 687                 break;
 688         }
 689 out:
 690         free_page((unsigned long) sccb);
 691         return rc;
 692 }
 693
 694 /**
 695  * sclp_chp_configure - perform configure channel-path sclp command
 696  * @chpid: channel-path ID
 697  *
 698  * Perform configure channel-path command sclp command for specified chpid.
 699  * Return 0 after command successfully finished, non-zero otherwise.
 700  */
 701 int sclp_chp_configure(struct chp_id chpid)
 702 {
 703         return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
 704 }
 705
 706 /**
 707  * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
 708  * @chpid: channel-path ID
 709  *
 710  * Perform deconfigure channel-path command sclp command for specified chpid
 711  * and wait for completion. On success return 0. Return non-zero otherwise.
 712  */
 713 int sclp_chp_deconfigure(struct chp_id chpid)
 714 {
 715         return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
 716 }
 717
 718 struct chp_info_sccb {
 719         struct sccb_header header;
 720         u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
 721         u8 standby[SCLP_CHP_INFO_MASK_SIZE];
 722         u8 configured[SCLP_CHP_INFO_MASK_SIZE];
 723         u8 ccm;
 724         u8 reserved[6];
 725         u8 cssid;
 726 } __attribute__((packed));
 727
 728 /**
 729  * sclp_chp_read_info - perform read channel-path information sclp command
 730  * @info: resulting channel-path information data
 731  *
 732  * Perform read channel-path information sclp command and wait for completion.
 733  * On success, store channel-path information in @info and return 0. Return
 734  * non-zero otherwise.
 735  */
 736 int sclp_chp_read_info(struct sclp_chp_info *info)
 737 {
 738         struct chp_info_sccb *sccb;
 739         int rc;
 740
 741         if (!SCLP_HAS_CHP_INFO)
 742                 return -EOPNOTSUPP;
 743         /* Prepare sccb. */
 744         sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 745         if (!sccb)
 746                 return -ENOMEM;
 747         sccb->header.length = sizeof(*sccb);
 748         rc = do_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
 749         if (rc)
 750                 goto out;
 751         if (sccb->header.response_code != 0x0010) {
 752                 pr_warning("read channel-path info failed "
 753                            "(response=0x%04x)\n", sccb->header.response_code);
 754                 rc = -EIO;
 755                 goto out;
 756         }
 757         memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
 758         memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
 759         memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
 760 out:
 761         free_page((unsigned long) sccb);
 762         return rc;
 763 }