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