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