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/module.h>
  21 #include <linux/platform_device.h>
  22 #include <asm/chpid.h>
  23 #include <asm/sclp.h>
  24 #include <asm/setup.h>
  25 #include <asm/ctl_reg.h>
  26
  27 #include "sclp.h"
  28
  29 #define SCLP_CMDW_READ_SCP_INFO         0x00020001
  30 #define SCLP_CMDW_READ_SCP_INFO_FORCED  0x00120001
  31
  32 struct read_info_sccb {
  33         struct  sccb_header header;     /* 0-7 */
  34         u16     rnmax;                  /* 8-9 */
  35         u8      rnsize;                 /* 10 */
  36         u8      _reserved0[24 - 11];    /* 11-15 */
  37         u8      loadparm[8];            /* 24-31 */
  38         u8      _reserved1[48 - 32];    /* 32-47 */
  39         u64     facilities;             /* 48-55 */
  40         u8      _reserved2[84 - 56];    /* 56-83 */
  41         u8      fac84;                  /* 84 */
  42         u8      fac85;                  /* 85 */
  43         u8      _reserved3[91 - 86];    /* 86-90 */
  44         u8      flags;                  /* 91 */
  45         u8      _reserved4[100 - 92];   /* 92-99 */
  46         u32     rnsize2;                /* 100-103 */
  47         u64     rnmax2;                 /* 104-111 */
  48         u8      _reserved5[4096 - 112]; /* 112-4095 */
  49 } __attribute__((packed, aligned(PAGE_SIZE)));
  50
  51 static struct init_sccb __initdata early_event_mask_sccb __aligned(PAGE_SIZE);
  52 static struct read_info_sccb __initdata early_read_info_sccb;
  53 static int __initdata early_read_info_sccb_valid;
  54
  55 u64 sclp_facilities;
  56 static u8 sclp_fac84;
  57 static u8 sclp_fac85;
  58 static unsigned long long rzm;
  59 static unsigned long long rnmax;
  60
  61 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
  62 {
  63         int rc;
  64
  65         __ctl_set_bit(0, 9);
  66         rc = sclp_service_call(cmd, sccb);
  67         if (rc)
  68                 goto out;
  69         __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
  70                         PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
  71         local_irq_disable();
  72 out:
  73         /* Contents of the sccb might have changed. */
  74         barrier();
  75         __ctl_clear_bit(0, 9);
  76         return rc;
  77 }
  78
  79 static void __init sclp_read_info_early(void)
  80 {
  81         int rc;
  82         int i;
  83         struct read_info_sccb *sccb;
  84         sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
  85                                   SCLP_CMDW_READ_SCP_INFO};
  86
  87         sccb = &early_read_info_sccb;
  88         for (i = 0; i < ARRAY_SIZE(commands); i++) {
  89                 do {
  90                         memset(sccb, 0, sizeof(*sccb));
  91                         sccb->header.length = sizeof(*sccb);
  92                         sccb->header.function_code = 0x80;
  93                         sccb->header.control_mask[2] = 0x80;
  94                         rc = sclp_cmd_sync_early(commands[i], sccb);
  95                 } while (rc == -EBUSY);
  96
  97                 if (rc)
  98                         break;
  99                 if (sccb->header.response_code == 0x10) {
 100                         early_read_info_sccb_valid = 1;
 101                         break;
 102                 }
 103                 if (sccb->header.response_code != 0x1f0)
 104                         break;
 105         }
 106 }
 107
 108 static void __init sclp_event_mask_early(void)
 109 {
 110         struct init_sccb *sccb = &early_event_mask_sccb;
 111         int rc;
 112
 113         do {
 114                 memset(sccb, 0, sizeof(*sccb));
 115                 sccb->header.length = sizeof(*sccb);
 116                 sccb->mask_length = sizeof(sccb_mask_t);
 117                 rc = sclp_cmd_sync_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
 118         } while (rc == -EBUSY);
 119 }
 120
 121 void __init sclp_facilities_detect(void)
 122 {
 123         struct read_info_sccb *sccb;
 124
 125         sclp_read_info_early();
 126         if (!early_read_info_sccb_valid)
 127                 return;
 128
 129         sccb = &early_read_info_sccb;
 130         sclp_facilities = sccb->facilities;
 131         sclp_fac84 = sccb->fac84;
 132         sclp_fac85 = sccb->fac85;
 133         rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 134         rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 135         rzm <<= 20;
 136
 137         sclp_event_mask_early();
 138 }
 139
 140 bool __init sclp_has_linemode(void)
 141 {
 142         struct init_sccb *sccb = &early_event_mask_sccb;
 143
 144         if (sccb->header.response_code != 0x20)
 145                 return 0;
 146         if (sccb->sclp_send_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK))
 147                 return 1;
 148         return 0;
 149 }
 150
 151 bool __init sclp_has_vt220(void)
 152 {
 153         struct init_sccb *sccb = &early_event_mask_sccb;
 154
 155         if (sccb->header.response_code != 0x20)
 156                 return 0;
 157         if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
 158                 return 1;
 159         return 0;
 160 }
 161
 162 unsigned long long sclp_get_rnmax(void)
 163 {
 164         return rnmax;
 165 }
 166
 167 unsigned long long sclp_get_rzm(void)
 168 {
 169         return rzm;
 170 }
 171
 172 u8 sclp_get_fac85(void)
 173 {
 174         return sclp_fac85;
 175 }
 176 EXPORT_SYMBOL_GPL(sclp_get_fac85);
 177
 178 /*
 179  * This function will be called after sclp_facilities_detect(), which gets
 180  * called from early.c code. Therefore the sccb should have valid contents.
 181  */
 182 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
 183 {
 184         struct read_info_sccb *sccb;
 185
 186         if (!early_read_info_sccb_valid)
 187                 return;
 188         sccb = &early_read_info_sccb;
 189         info->is_valid = 1;
 190         if (sccb->flags & 0x2)
 191                 info->has_dump = 1;
 192         memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
 193 }
 194
 195 static void sclp_sync_callback(struct sclp_req *req, void *data)
 196 {
 197         struct completion *completion = data;
 198
 199         complete(completion);
 200 }
 201
 202 static int do_sync_request(sclp_cmdw_t cmd, void *sccb)
 203 {
 204         struct completion completion;
 205         struct sclp_req *request;
 206         int rc;
 207
 208         request = kzalloc(sizeof(*request), GFP_KERNEL);
 209         if (!request)
 210                 return -ENOMEM;
 211         request->command = cmd;
 212         request->sccb = sccb;
 213         request->status = SCLP_REQ_FILLED;
 214         request->callback = sclp_sync_callback;
 215         request->callback_data = &completion;
 216         init_completion(&completion);
 217
 218         /* Perform sclp request. */
 219         rc = sclp_add_request(request);
 220         if (rc)
 221                 goto out;
 222         wait_for_completion(&completion);
 223
 224         /* Check response. */
 225         if (request->status != SCLP_REQ_DONE) {
 226                 pr_warning("sync request failed (cmd=0x%08x, "
 227                            "status=0x%02x)\n", cmd, request->status);
 228                 rc = -EIO;
 229         }
 230 out:
 231         kfree(request);
 232         return rc;
 233 }
 234
 235 /*
 236  * CPU configuration related functions.
 237  */
 238
 239 #define SCLP_CMDW_READ_CPU_INFO         0x00010001
 240 #define SCLP_CMDW_CONFIGURE_CPU         0x00110001
 241 #define SCLP_CMDW_DECONFIGURE_CPU       0x00100001
 242
 243 struct read_cpu_info_sccb {
 244         struct  sccb_header header;
 245         u16     nr_configured;
 246         u16     offset_configured;
 247         u16     nr_standby;
 248         u16     offset_standby;
 249         u8      reserved[4096 - 16];
 250 } __attribute__((packed, aligned(PAGE_SIZE)));
 251
 252 static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
 253                                struct read_cpu_info_sccb *sccb)
 254 {
 255         char *page = (char *) sccb;
 256
 257         memset(info, 0, sizeof(*info));
 258         info->configured = sccb->nr_configured;
 259         info->standby = sccb->nr_standby;
 260         info->combined = sccb->nr_configured + sccb->nr_standby;
 261         info->has_cpu_type = sclp_fac84 & 0x1;
 262         memcpy(&info->cpu, page + sccb->offset_configured,
 263                info->combined * sizeof(struct sclp_cpu_entry));
 264 }
 265
 266 int sclp_get_cpu_info(struct sclp_cpu_info *info)
 267 {
 268         int rc;
 269         struct read_cpu_info_sccb *sccb;
 270
 271         if (!SCLP_HAS_CPU_INFO)
 272                 return -EOPNOTSUPP;
 273         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 274         if (!sccb)
 275                 return -ENOMEM;
 276         sccb->header.length = sizeof(*sccb);
 277         rc = do_sync_request(SCLP_CMDW_READ_CPU_INFO, sccb);
 278         if (rc)
 279                 goto out;
 280         if (sccb->header.response_code != 0x0010) {
 281                 pr_warning("readcpuinfo failed (response=0x%04x)\n",
 282                            sccb->header.response_code);
 283                 rc = -EIO;
 284                 goto out;
 285         }
 286         sclp_fill_cpu_info(info, sccb);
 287 out:
 288         free_page((unsigned long) sccb);
 289         return rc;
 290 }
 291
 292 struct cpu_configure_sccb {
 293         struct sccb_header header;
 294 } __attribute__((packed, aligned(8)));
 295
 296 static int do_cpu_configure(sclp_cmdw_t cmd)
 297 {
 298         struct cpu_configure_sccb *sccb;
 299         int rc;
 300
 301         if (!SCLP_HAS_CPU_RECONFIG)
 302                 return -EOPNOTSUPP;
 303         /*
 304          * This is not going to cross a page boundary since we force
 305          * kmalloc to have a minimum alignment of 8 bytes on s390.
 306          */
 307         sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
 308         if (!sccb)
 309                 return -ENOMEM;
 310         sccb->header.length = sizeof(*sccb);
 311         rc = do_sync_request(cmd, sccb);
 312         if (rc)
 313                 goto out;
 314         switch (sccb->header.response_code) {
 315         case 0x0020:
 316         case 0x0120:
 317                 break;
 318         default:
 319                 pr_warning("configure cpu failed (cmd=0x%08x, "
 320                            "response=0x%04x)\n", cmd,
 321                            sccb->header.response_code);
 322                 rc = -EIO;
 323                 break;
 324         }
 325 out:
 326         kfree(sccb);
 327         return rc;
 328 }
 329
 330 int sclp_cpu_configure(u8 cpu)
 331 {
 332         return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
 333 }
 334
 335 int sclp_cpu_deconfigure(u8 cpu)
 336 {
 337         return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
 338 }
 339
 340 #ifdef CONFIG_MEMORY_HOTPLUG
 341
 342 static DEFINE_MUTEX(sclp_mem_mutex);
 343 static LIST_HEAD(sclp_mem_list);
 344 static u8 sclp_max_storage_id;
 345 static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
 346 static int sclp_mem_state_changed;
 347
 348 struct memory_increment {
 349         struct list_head list;
 350         u16 rn;
 351         int standby;
 352         int usecount;
 353 };
 354
 355 struct assign_storage_sccb {
 356         struct sccb_header header;
 357         u16 rn;
 358 } __packed;
 359
 360 int arch_get_memory_phys_device(unsigned long start_pfn)
 361 {
 362         if (!rzm)
 363                 return 0;
 364         return PFN_PHYS(start_pfn) >> ilog2(rzm);
 365 }
 366
 367 static unsigned long long rn2addr(u16 rn)
 368 {
 369         return (unsigned long long) (rn - 1) * rzm;
 370 }
 371
 372 static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
 373 {
 374         struct assign_storage_sccb *sccb;
 375         int rc;
 376
 377         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 378         if (!sccb)
 379                 return -ENOMEM;
 380         sccb->header.length = PAGE_SIZE;
 381         sccb->rn = rn;
 382         rc = do_sync_request(cmd, sccb);
 383         if (rc)
 384                 goto out;
 385         switch (sccb->header.response_code) {
 386         case 0x0020:
 387         case 0x0120:
 388                 break;
 389         default:
 390                 pr_warning("assign storage failed (cmd=0x%08x, "
 391                            "response=0x%04x, rn=0x%04x)\n", cmd,
 392                            sccb->header.response_code, rn);
 393                 rc = -EIO;
 394                 break;
 395         }
 396 out:
 397         free_page((unsigned long) sccb);
 398         return rc;
 399 }
 400
 401 static int sclp_assign_storage(u16 rn)
 402 {
 403         unsigned long long start, address;
 404         int rc;
 405
 406         rc = do_assign_storage(0x000d0001, rn);
 407         if (rc)
 408                 goto out;
 409         start = address = rn2addr(rn);
 410         for (; address < start + rzm; address += PAGE_SIZE)
 411                 page_set_storage_key(address, PAGE_DEFAULT_KEY, 0);
 412 out:
 413         return rc;
 414 }
 415
 416 static int sclp_unassign_storage(u16 rn)
 417 {
 418         return do_assign_storage(0x000c0001, rn);
 419 }
 420
 421 struct attach_storage_sccb {
 422         struct sccb_header header;
 423         u16 :16;
 424         u16 assigned;
 425         u32 :32;
 426         u32 entries[0];
 427 } __packed;
 428
 429 static int sclp_attach_storage(u8 id)
 430 {
 431         struct attach_storage_sccb *sccb;
 432         int rc;
 433         int i;
 434
 435         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 436         if (!sccb)
 437                 return -ENOMEM;
 438         sccb->header.length = PAGE_SIZE;
 439         rc = do_sync_request(0x00080001 | id << 8, sccb);
 440         if (rc)
 441                 goto out;
 442         switch (sccb->header.response_code) {
 443         case 0x0020:
 444                 set_bit(id, sclp_storage_ids);
 445                 for (i = 0; i < sccb->assigned; i++) {
 446                         if (sccb->entries[i])
 447                                 sclp_unassign_storage(sccb->entries[i] >> 16);
 448                 }
 449                 break;
 450         default:
 451                 rc = -EIO;
 452                 break;
 453         }
 454 out:
 455         free_page((unsigned long) sccb);
 456         return rc;
 457 }
 458
 459 static int sclp_mem_change_state(unsigned long start, unsigned long size,
 460                                  int online)
 461 {
 462         struct memory_increment *incr;
 463         unsigned long long istart;
 464         int rc = 0;
 465
 466         list_for_each_entry(incr, &sclp_mem_list, list) {
 467                 istart = rn2addr(incr->rn);
 468                 if (start + size - 1 < istart)
 469                         break;
 470                 if (start > istart + rzm - 1)
 471                         continue;
 472                 if (online) {
 473                         if (incr->usecount++)
 474                                 continue;
 475                         /*
 476                          * Don't break the loop if one assign fails. Loop may
 477                          * be walked again on CANCEL and we can't save
 478                          * information if state changed before or not.
 479                          * So continue and increase usecount for all increments.
 480                          */
 481                         rc |= sclp_assign_storage(incr->rn);
 482                 } else {
 483                         if (--incr->usecount)
 484                                 continue;
 485                         sclp_unassign_storage(incr->rn);
 486                 }
 487         }
 488         return rc ? -EIO : 0;
 489 }
 490
 491 static int sclp_mem_notifier(struct notifier_block *nb,
 492                              unsigned long action, void *data)
 493 {
 494         unsigned long start, size;
 495         struct memory_notify *arg;
 496         unsigned char id;
 497         int rc = 0;
 498
 499         arg = data;
 500         start = arg->start_pfn << PAGE_SHIFT;
 501         size = arg->nr_pages << PAGE_SHIFT;
 502         mutex_lock(&sclp_mem_mutex);
 503         for_each_clear_bit(id, sclp_storage_ids, sclp_max_storage_id + 1)
 504                 sclp_attach_storage(id);
 505         switch (action) {
 506         case MEM_ONLINE:
 507         case MEM_GOING_OFFLINE:
 508         case MEM_CANCEL_OFFLINE:
 509                 break;
 510         case MEM_GOING_ONLINE:
 511                 rc = sclp_mem_change_state(start, size, 1);
 512                 break;
 513         case MEM_CANCEL_ONLINE:
 514                 sclp_mem_change_state(start, size, 0);
 515                 break;
 516         case MEM_OFFLINE:
 517                 sclp_mem_change_state(start, size, 0);
 518                 break;
 519         default:
 520                 rc = -EINVAL;
 521                 break;
 522         }
 523         if (!rc)
 524                 sclp_mem_state_changed = 1;
 525         mutex_unlock(&sclp_mem_mutex);
 526         return rc ? NOTIFY_BAD : NOTIFY_OK;
 527 }
 528
 529 static struct notifier_block sclp_mem_nb = {
 530         .notifier_call = sclp_mem_notifier,
 531 };
 532
 533 static void __init add_memory_merged(u16 rn)
 534 {
 535         static u16 first_rn, num;
 536         unsigned long long start, size;
 537
 538         if (rn && first_rn && (first_rn + num == rn)) {
 539                 num++;
 540                 return;
 541         }
 542         if (!first_rn)
 543                 goto skip_add;
 544         start = rn2addr(first_rn);
 545         size = (unsigned long long ) num * rzm;
 546         if (start >= VMEM_MAX_PHYS)
 547                 goto skip_add;
 548         if (start + size > VMEM_MAX_PHYS)
 549                 size = VMEM_MAX_PHYS - start;
 550         if (memory_end_set && (start >= memory_end))
 551                 goto skip_add;
 552         if (memory_end_set && (start + size > memory_end))
 553                 size = memory_end - start;
 554         add_memory(0, start, size);
 555 skip_add:
 556         first_rn = rn;
 557         num = 1;
 558 }
 559
 560 static void __init sclp_add_standby_memory(void)
 561 {
 562         struct memory_increment *incr;
 563
 564         list_for_each_entry(incr, &sclp_mem_list, list)
 565                 if (incr->standby)
 566                         add_memory_merged(incr->rn);
 567         add_memory_merged(0);
 568 }
 569
 570 static void __init insert_increment(u16 rn, int standby, int assigned)
 571 {
 572         struct memory_increment *incr, *new_incr;
 573         struct list_head *prev;
 574         u16 last_rn;
 575
 576         new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
 577         if (!new_incr)
 578                 return;
 579         new_incr->rn = rn;
 580         new_incr->standby = standby;
 581         if (!standby)
 582                 new_incr->usecount = 1;
 583         last_rn = 0;
 584         prev = &sclp_mem_list;
 585         list_for_each_entry(incr, &sclp_mem_list, list) {
 586                 if (assigned && incr->rn > rn)
 587                         break;
 588                 if (!assigned && incr->rn - last_rn > 1)
 589                         break;
 590                 last_rn = incr->rn;
 591                 prev = &incr->list;
 592         }
 593         if (!assigned)
 594                 new_incr->rn = last_rn + 1;
 595         if (new_incr->rn > rnmax) {
 596                 kfree(new_incr);
 597                 return;
 598         }
 599         list_add(&new_incr->list, prev);
 600 }
 601
 602 static int sclp_mem_freeze(struct device *dev)
 603 {
 604         if (!sclp_mem_state_changed)
 605                 return 0;
 606         pr_err("Memory hotplug state changed, suspend refused.\n");
 607         return -EPERM;
 608 }
 609
 610 struct read_storage_sccb {
 611         struct sccb_header header;
 612         u16 max_id;
 613         u16 assigned;
 614         u16 standby;
 615         u16 :16;
 616         u32 entries[0];
 617 } __packed;
 618
 619 static const struct dev_pm_ops sclp_mem_pm_ops = {
 620         .freeze         = sclp_mem_freeze,
 621 };
 622
 623 static struct platform_driver sclp_mem_pdrv = {
 624         .driver = {
 625                 .name   = "sclp_mem",
 626                 .pm     = &sclp_mem_pm_ops,
 627         },
 628 };
 629
 630 static int __init sclp_detect_standby_memory(void)
 631 {
 632         struct platform_device *sclp_pdev;
 633         struct read_storage_sccb *sccb;
 634         int i, id, assigned, rc;
 635
 636         if (!early_read_info_sccb_valid)
 637                 return 0;
 638         if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
 639                 return 0;
 640         rc = -ENOMEM;
 641         sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
 642         if (!sccb)
 643                 goto out;
 644         assigned = 0;
 645         for (id = 0; id <= sclp_max_storage_id; id++) {
 646                 memset(sccb, 0, PAGE_SIZE);
 647                 sccb->header.length = PAGE_SIZE;
 648                 rc = do_sync_request(0x00040001 | id << 8, sccb);
 649                 if (rc)
 650                         goto out;
 651                 switch (sccb->header.response_code) {
 652                 case 0x0010:
 653                         set_bit(id, sclp_storage_ids);
 654                         for (i = 0; i < sccb->assigned; i++) {
 655                                 if (!sccb->entries[i])
 656                                         continue;
 657                                 assigned++;
 658                                 insert_increment(sccb->entries[i] >> 16, 0, 1);
 659                         }
 660                         break;
 661                 case 0x0310:
 662                         break;
 663                 case 0x0410:
 664                         for (i = 0; i < sccb->assigned; i++) {
 665                                 if (!sccb->entries[i])
 666                                         continue;
 667                                 assigned++;
 668                                 insert_increment(sccb->entries[i] >> 16, 1, 1);
 669                         }
 670                         break;
 671                 default:
 672                         rc = -EIO;
 673                         break;
 674                 }
 675                 if (!rc)
 676                         sclp_max_storage_id = sccb->max_id;
 677         }
 678         if (rc || list_empty(&sclp_mem_list))
 679                 goto out;
 680         for (i = 1; i <= rnmax - assigned; i++)
 681                 insert_increment(0, 1, 0);
 682         rc = register_memory_notifier(&sclp_mem_nb);
 683         if (rc)
 684                 goto out;
 685         rc = platform_driver_register(&sclp_mem_pdrv);
 686         if (rc)
 687                 goto out;
 688         sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
 689         rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
 690         if (rc)
 691                 goto out_driver;
 692         sclp_add_standby_memory();
 693         goto out;
 694 out_driver:
 695         platform_driver_unregister(&sclp_mem_pdrv);
 696 out:
 697         free_page((unsigned long) sccb);
 698         return rc;
 699 }
 700 __initcall(sclp_detect_standby_memory);
 701
 702 #endif /* CONFIG_MEMORY_HOTPLUG */
 703
 704 /*
 705  * Channel path configuration related functions.
 706  */
 707
 708 #define SCLP_CMDW_CONFIGURE_CHPATH              0x000f0001
 709 #define SCLP_CMDW_DECONFIGURE_CHPATH            0x000e0001
 710 #define SCLP_CMDW_READ_CHPATH_INFORMATION       0x00030001
 711
 712 struct chp_cfg_sccb {
 713         struct sccb_header header;
 714         u8 ccm;
 715         u8 reserved[6];
 716         u8 cssid;
 717 } __attribute__((packed));
 718
 719 static int do_chp_configure(sclp_cmdw_t cmd)
 720 {
 721         struct chp_cfg_sccb *sccb;
 722         int rc;
 723
 724         if (!SCLP_HAS_CHP_RECONFIG)
 725                 return -EOPNOTSUPP;
 726         /* Prepare sccb. */
 727         sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 728         if (!sccb)
 729                 return -ENOMEM;
 730         sccb->header.length = sizeof(*sccb);
 731         rc = do_sync_request(cmd, sccb);
 732         if (rc)
 733                 goto out;
 734         switch (sccb->header.response_code) {
 735         case 0x0020:
 736         case 0x0120:
 737         case 0x0440:
 738         case 0x0450:
 739                 break;
 740         default:
 741                 pr_warning("configure channel-path failed "
 742                            "(cmd=0x%08x, response=0x%04x)\n", cmd,
 743                            sccb->header.response_code);
 744                 rc = -EIO;
 745                 break;
 746         }
 747 out:
 748         free_page((unsigned long) sccb);
 749         return rc;
 750 }
 751
 752 /**
 753  * sclp_chp_configure - perform configure channel-path sclp command
 754  * @chpid: channel-path ID
 755  *
 756  * Perform configure channel-path command sclp command for specified chpid.
 757  * Return 0 after command successfully finished, non-zero otherwise.
 758  */
 759 int sclp_chp_configure(struct chp_id chpid)
 760 {
 761         return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
 762 }
 763
 764 /**
 765  * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
 766  * @chpid: channel-path ID
 767  *
 768  * Perform deconfigure channel-path command sclp command for specified chpid
 769  * and wait for completion. On success return 0. Return non-zero otherwise.
 770  */
 771 int sclp_chp_deconfigure(struct chp_id chpid)
 772 {
 773         return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
 774 }
 775
 776 struct chp_info_sccb {
 777         struct sccb_header header;
 778         u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
 779         u8 standby[SCLP_CHP_INFO_MASK_SIZE];
 780         u8 configured[SCLP_CHP_INFO_MASK_SIZE];
 781         u8 ccm;
 782         u8 reserved[6];
 783         u8 cssid;
 784 } __attribute__((packed));
 785
 786 /**
 787  * sclp_chp_read_info - perform read channel-path information sclp command
 788  * @info: resulting channel-path information data
 789  *
 790  * Perform read channel-path information sclp command and wait for completion.
 791  * On success, store channel-path information in @info and return 0. Return
 792  * non-zero otherwise.
 793  */
 794 int sclp_chp_read_info(struct sclp_chp_info *info)
 795 {
 796         struct chp_info_sccb *sccb;
 797         int rc;
 798
 799         if (!SCLP_HAS_CHP_INFO)
 800                 return -EOPNOTSUPP;
 801         /* Prepare sccb. */
 802         sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 803         if (!sccb)
 804                 return -ENOMEM;
 805         sccb->header.length = sizeof(*sccb);
 806         rc = do_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
 807         if (rc)
 808                 goto out;
 809         if (sccb->header.response_code != 0x0010) {
 810                 pr_warning("read channel-path info failed "
 811                            "(response=0x%04x)\n", sccb->header.response_code);
 812                 rc = -EIO;
 813                 goto out;
 814         }
 815         memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
 816         memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
 817         memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
 818 out:
 819         free_page((unsigned long) sccb);
 820         return rc;
 821 }