1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * S390 kdump implementation 4 * 5 * Copyright IBM Corp. 2011 6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com> 7 */ 8 9 #include <linux/crash_dump.h> 10 #include <asm/lowcore.h> 11 #include <linux/kernel.h> 12 #include <linux/init.h> 13 #include <linux/mm.h> 14 #include <linux/gfp.h> 15 #include <linux/slab.h> 16 #include <linux/bootmem.h> 17 #include <linux/elf.h> 18 #include <asm/asm-offsets.h> 19 #include <linux/memblock.h> 20 #include <asm/os_info.h> 21 #include <asm/elf.h> 22 #include <asm/ipl.h> 23 #include <asm/sclp.h> 24 25 #define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y))) 26 #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y))) 27 #define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y)))) 28 29 static struct memblock_region oldmem_region; 30 31 static struct memblock_type oldmem_type = { 32 .cnt = 1, 33 .max = 1, 34 .total_size = 0, 35 .regions = &oldmem_region, 36 .name = "oldmem", 37 }; 38 39 struct save_area { 40 struct list_head list; 41 u64 psw[2]; 42 u64 ctrs[16]; 43 u64 gprs[16]; 44 u32 acrs[16]; 45 u64 fprs[16]; 46 u32 fpc; 47 u32 prefix; 48 u64 todpreg; 49 u64 timer; 50 u64 todcmp; 51 u64 vxrs_low[16]; 52 __vector128 vxrs_high[16]; 53 }; 54 55 static LIST_HEAD(dump_save_areas); 56 57 /* 58 * Allocate a save area 59 */ 60 struct save_area * __init save_area_alloc(bool is_boot_cpu) 61 { 62 struct save_area *sa; 63 64 sa = (void *) memblock_alloc(sizeof(*sa), 8); 65 if (is_boot_cpu) 66 list_add(&sa->list, &dump_save_areas); 67 else 68 list_add_tail(&sa->list, &dump_save_areas); 69 return sa; 70 } 71 72 /* 73 * Return the address of the save area for the boot CPU 74 */ 75 struct save_area * __init save_area_boot_cpu(void) 76 { 77 return list_first_entry_or_null(&dump_save_areas, struct save_area, list); 78 } 79 80 /* 81 * Copy CPU registers into the save area 82 */ 83 void __init save_area_add_regs(struct save_area *sa, void *regs) 84 { 85 struct lowcore *lc; 86 87 lc = (struct lowcore *)(regs - __LC_FPREGS_SAVE_AREA); 88 memcpy(&sa->psw, &lc->psw_save_area, sizeof(sa->psw)); 89 memcpy(&sa->ctrs, &lc->cregs_save_area, sizeof(sa->ctrs)); 90 memcpy(&sa->gprs, &lc->gpregs_save_area, sizeof(sa->gprs)); 91 memcpy(&sa->acrs, &lc->access_regs_save_area, sizeof(sa->acrs)); 92 memcpy(&sa->fprs, &lc->floating_pt_save_area, sizeof(sa->fprs)); 93 memcpy(&sa->fpc, &lc->fpt_creg_save_area, sizeof(sa->fpc)); 94 memcpy(&sa->prefix, &lc->prefixreg_save_area, sizeof(sa->prefix)); 95 memcpy(&sa->todpreg, &lc->tod_progreg_save_area, sizeof(sa->todpreg)); 96 memcpy(&sa->timer, &lc->cpu_timer_save_area, sizeof(sa->timer)); 97 memcpy(&sa->todcmp, &lc->clock_comp_save_area, sizeof(sa->todcmp)); 98 } 99 100 /* 101 * Copy vector registers into the save area 102 */ 103 void __init save_area_add_vxrs(struct save_area *sa, __vector128 *vxrs) 104 { 105 int i; 106 107 /* Copy lower halves of vector registers 0-15 */ 108 for (i = 0; i < 16; i++) 109 memcpy(&sa->vxrs_low[i], &vxrs[i].u[2], 8); 110 /* Copy vector registers 16-31 */ 111 memcpy(sa->vxrs_high, vxrs + 16, 16 * sizeof(__vector128)); 112 } 113 114 /* 115 * Return physical address for virtual address 116 */ 117 static inline void *load_real_addr(void *addr) 118 { 119 unsigned long real_addr; 120 121 asm volatile( 122 " lra %0,0(%1)\n" 123 " jz 0f\n" 124 " la %0,0\n" 125 "0:" 126 : "=a" (real_addr) : "a" (addr) : "cc"); 127 return (void *)real_addr; 128 } 129 130 /* 131 * Copy memory of the old, dumped system to a kernel space virtual address 132 */ 133 int copy_oldmem_kernel(void *dst, void *src, size_t count) 134 { 135 unsigned long from, len; 136 void *ra; 137 int rc; 138 139 while (count) { 140 from = __pa(src); 141 if (!OLDMEM_BASE && from < sclp.hsa_size) { 142 /* Copy from zfcpdump HSA area */ 143 len = min(count, sclp.hsa_size - from); 144 rc = memcpy_hsa_kernel(dst, from, len); 145 if (rc) 146 return rc; 147 } else { 148 /* Check for swapped kdump oldmem areas */ 149 if (OLDMEM_BASE && from - OLDMEM_BASE < OLDMEM_SIZE) { 150 from -= OLDMEM_BASE; 151 len = min(count, OLDMEM_SIZE - from); 152 } else if (OLDMEM_BASE && from < OLDMEM_SIZE) { 153 len = min(count, OLDMEM_SIZE - from); 154 from += OLDMEM_BASE; 155 } else { 156 len = count; 157 } 158 if (is_vmalloc_or_module_addr(dst)) { 159 ra = load_real_addr(dst); 160 len = min(PAGE_SIZE - offset_in_page(ra), len); 161 } else { 162 ra = dst; 163 } 164 if (memcpy_real(ra, (void *) from, len)) 165 return -EFAULT; 166 } 167 dst += len; 168 src += len; 169 count -= len; 170 } 171 return 0; 172 } 173 174 /* 175 * Copy memory of the old, dumped system to a user space virtual address 176 */ 177 static int copy_oldmem_user(void __user *dst, void *src, size_t count) 178 { 179 unsigned long from, len; 180 int rc; 181 182 while (count) { 183 from = __pa(src); 184 if (!OLDMEM_BASE && from < sclp.hsa_size) { 185 /* Copy from zfcpdump HSA area */ 186 len = min(count, sclp.hsa_size - from); 187 rc = memcpy_hsa_user(dst, from, len); 188 if (rc) 189 return rc; 190 } else { 191 /* Check for swapped kdump oldmem areas */ 192 if (OLDMEM_BASE && from - OLDMEM_BASE < OLDMEM_SIZE) { 193 from -= OLDMEM_BASE; 194 len = min(count, OLDMEM_SIZE - from); 195 } else if (OLDMEM_BASE && from < OLDMEM_SIZE) { 196 len = min(count, OLDMEM_SIZE - from); 197 from += OLDMEM_BASE; 198 } else { 199 len = count; 200 } 201 rc = copy_to_user_real(dst, (void *) from, count); 202 if (rc) 203 return rc; 204 } 205 dst += len; 206 src += len; 207 count -= len; 208 } 209 return 0; 210 } 211 212 /* 213 * Copy one page from "oldmem" 214 */ 215 ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, 216 unsigned long offset, int userbuf) 217 { 218 void *src; 219 int rc; 220 221 if (!csize) 222 return 0; 223 src = (void *) (pfn << PAGE_SHIFT) + offset; 224 if (userbuf) 225 rc = copy_oldmem_user((void __force __user *) buf, src, csize); 226 else 227 rc = copy_oldmem_kernel((void *) buf, src, csize); 228 return rc; 229 } 230 231 /* 232 * Remap "oldmem" for kdump 233 * 234 * For the kdump reserved memory this functions performs a swap operation: 235 * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] 236 */ 237 static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma, 238 unsigned long from, unsigned long pfn, 239 unsigned long size, pgprot_t prot) 240 { 241 unsigned long size_old; 242 int rc; 243 244 if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) { 245 size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT)); 246 rc = remap_pfn_range(vma, from, 247 pfn + (OLDMEM_BASE >> PAGE_SHIFT), 248 size_old, prot); 249 if (rc || size == size_old) 250 return rc; 251 size -= size_old; 252 from += size_old; 253 pfn += size_old >> PAGE_SHIFT; 254 } 255 return remap_pfn_range(vma, from, pfn, size, prot); 256 } 257 258 /* 259 * Remap "oldmem" for zfcpdump 260 * 261 * We only map available memory above HSA size. Memory below HSA size 262 * is read on demand using the copy_oldmem_page() function. 263 */ 264 static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma, 265 unsigned long from, 266 unsigned long pfn, 267 unsigned long size, pgprot_t prot) 268 { 269 unsigned long hsa_end = sclp.hsa_size; 270 unsigned long size_hsa; 271 272 if (pfn < hsa_end >> PAGE_SHIFT) { 273 size_hsa = min(size, hsa_end - (pfn << PAGE_SHIFT)); 274 if (size == size_hsa) 275 return 0; 276 size -= size_hsa; 277 from += size_hsa; 278 pfn += size_hsa >> PAGE_SHIFT; 279 } 280 return remap_pfn_range(vma, from, pfn, size, prot); 281 } 282 283 /* 284 * Remap "oldmem" for kdump or zfcpdump 285 */ 286 int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from, 287 unsigned long pfn, unsigned long size, pgprot_t prot) 288 { 289 if (OLDMEM_BASE) 290 return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot); 291 else 292 return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size, 293 prot); 294 } 295 296 static const char *nt_name(Elf64_Word type) 297 { 298 const char *name = "LINUX"; 299 300 if (type == NT_PRPSINFO || type == NT_PRSTATUS || type == NT_PRFPREG) 301 name = KEXEC_CORE_NOTE_NAME; 302 return name; 303 } 304 305 /* 306 * Initialize ELF note 307 */ 308 static void *nt_init_name(void *buf, Elf64_Word type, void *desc, int d_len, 309 const char *name) 310 { 311 Elf64_Nhdr *note; 312 u64 len; 313 314 note = (Elf64_Nhdr *)buf; 315 note->n_namesz = strlen(name) + 1; 316 note->n_descsz = d_len; 317 note->n_type = type; 318 len = sizeof(Elf64_Nhdr); 319 320 memcpy(buf + len, name, note->n_namesz); 321 len = roundup(len + note->n_namesz, 4); 322 323 memcpy(buf + len, desc, note->n_descsz); 324 len = roundup(len + note->n_descsz, 4); 325 326 return PTR_ADD(buf, len); 327 } 328 329 static inline void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len) 330 { 331 return nt_init_name(buf, type, desc, d_len, nt_name(type)); 332 } 333 334 /* 335 * Calculate the size of ELF note 336 */ 337 static size_t nt_size_name(int d_len, const char *name) 338 { 339 size_t size; 340 341 size = sizeof(Elf64_Nhdr); 342 size += roundup(strlen(name) + 1, 4); 343 size += roundup(d_len, 4); 344 345 return size; 346 } 347 348 static inline size_t nt_size(Elf64_Word type, int d_len) 349 { 350 return nt_size_name(d_len, nt_name(type)); 351 } 352 353 /* 354 * Fill ELF notes for one CPU with save area registers 355 */ 356 static void *fill_cpu_elf_notes(void *ptr, int cpu, struct save_area *sa) 357 { 358 struct elf_prstatus nt_prstatus; 359 elf_fpregset_t nt_fpregset; 360 361 /* Prepare prstatus note */ 362 memset(&nt_prstatus, 0, sizeof(nt_prstatus)); 363 memcpy(&nt_prstatus.pr_reg.gprs, sa->gprs, sizeof(sa->gprs)); 364 memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw)); 365 memcpy(&nt_prstatus.pr_reg.acrs, sa->acrs, sizeof(sa->acrs)); 366 nt_prstatus.pr_pid = cpu; 367 /* Prepare fpregset (floating point) note */ 368 memset(&nt_fpregset, 0, sizeof(nt_fpregset)); 369 memcpy(&nt_fpregset.fpc, &sa->fpc, sizeof(sa->fpc)); 370 memcpy(&nt_fpregset.fprs, &sa->fprs, sizeof(sa->fprs)); 371 /* Create ELF notes for the CPU */ 372 ptr = nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus)); 373 ptr = nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset)); 374 ptr = nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer)); 375 ptr = nt_init(ptr, NT_S390_TODCMP, &sa->todcmp, sizeof(sa->todcmp)); 376 ptr = nt_init(ptr, NT_S390_TODPREG, &sa->todpreg, sizeof(sa->todpreg)); 377 ptr = nt_init(ptr, NT_S390_CTRS, &sa->ctrs, sizeof(sa->ctrs)); 378 ptr = nt_init(ptr, NT_S390_PREFIX, &sa->prefix, sizeof(sa->prefix)); 379 if (MACHINE_HAS_VX) { 380 ptr = nt_init(ptr, NT_S390_VXRS_HIGH, 381 &sa->vxrs_high, sizeof(sa->vxrs_high)); 382 ptr = nt_init(ptr, NT_S390_VXRS_LOW, 383 &sa->vxrs_low, sizeof(sa->vxrs_low)); 384 } 385 return ptr; 386 } 387 388 /* 389 * Calculate size of ELF notes per cpu 390 */ 391 static size_t get_cpu_elf_notes_size(void) 392 { 393 struct save_area *sa = NULL; 394 size_t size; 395 396 size = nt_size(NT_PRSTATUS, sizeof(struct elf_prstatus)); 397 size += nt_size(NT_PRFPREG, sizeof(elf_fpregset_t)); 398 size += nt_size(NT_S390_TIMER, sizeof(sa->timer)); 399 size += nt_size(NT_S390_TODCMP, sizeof(sa->todcmp)); 400 size += nt_size(NT_S390_TODPREG, sizeof(sa->todpreg)); 401 size += nt_size(NT_S390_CTRS, sizeof(sa->ctrs)); 402 size += nt_size(NT_S390_PREFIX, sizeof(sa->prefix)); 403 if (MACHINE_HAS_VX) { 404 size += nt_size(NT_S390_VXRS_HIGH, sizeof(sa->vxrs_high)); 405 size += nt_size(NT_S390_VXRS_LOW, sizeof(sa->vxrs_low)); 406 } 407 408 return size; 409 } 410 411 /* 412 * Initialize prpsinfo note (new kernel) 413 */ 414 static void *nt_prpsinfo(void *ptr) 415 { 416 struct elf_prpsinfo prpsinfo; 417 418 memset(&prpsinfo, 0, sizeof(prpsinfo)); 419 prpsinfo.pr_sname = 'R'; 420 strcpy(prpsinfo.pr_fname, "vmlinux"); 421 return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo)); 422 } 423 424 /* 425 * Get vmcoreinfo using lowcore->vmcore_info (new kernel) 426 */ 427 static void *get_vmcoreinfo_old(unsigned long *size) 428 { 429 char nt_name[11], *vmcoreinfo; 430 Elf64_Nhdr note; 431 void *addr; 432 433 if (copy_oldmem_kernel(&addr, &S390_lowcore.vmcore_info, sizeof(addr))) 434 return NULL; 435 memset(nt_name, 0, sizeof(nt_name)); 436 if (copy_oldmem_kernel(¬e, addr, sizeof(note))) 437 return NULL; 438 if (copy_oldmem_kernel(nt_name, addr + sizeof(note), 439 sizeof(nt_name) - 1)) 440 return NULL; 441 if (strcmp(nt_name, VMCOREINFO_NOTE_NAME) != 0) 442 return NULL; 443 vmcoreinfo = kzalloc(note.n_descsz, GFP_KERNEL); 444 if (!vmcoreinfo) 445 return NULL; 446 if (copy_oldmem_kernel(vmcoreinfo, addr + 24, note.n_descsz)) { 447 kfree(vmcoreinfo); 448 return NULL; 449 } 450 *size = note.n_descsz; 451 return vmcoreinfo; 452 } 453 454 /* 455 * Initialize vmcoreinfo note (new kernel) 456 */ 457 static void *nt_vmcoreinfo(void *ptr) 458 { 459 const char *name = VMCOREINFO_NOTE_NAME; 460 unsigned long size; 461 void *vmcoreinfo; 462 463 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 464 if (vmcoreinfo) 465 return nt_init_name(ptr, 0, vmcoreinfo, size, name); 466 467 vmcoreinfo = get_vmcoreinfo_old(&size); 468 if (!vmcoreinfo) 469 return ptr; 470 ptr = nt_init_name(ptr, 0, vmcoreinfo, size, name); 471 kfree(vmcoreinfo); 472 return ptr; 473 } 474 475 static size_t nt_vmcoreinfo_size(void) 476 { 477 const char *name = VMCOREINFO_NOTE_NAME; 478 unsigned long size; 479 void *vmcoreinfo; 480 481 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 482 if (vmcoreinfo) 483 return nt_size_name(size, name); 484 485 vmcoreinfo = get_vmcoreinfo_old(&size); 486 if (!vmcoreinfo) 487 return 0; 488 489 kfree(vmcoreinfo); 490 return nt_size_name(size, name); 491 } 492 493 /* 494 * Initialize final note (needed for /proc/vmcore code) 495 */ 496 static void *nt_final(void *ptr) 497 { 498 Elf64_Nhdr *note; 499 500 note = (Elf64_Nhdr *) ptr; 501 note->n_namesz = 0; 502 note->n_descsz = 0; 503 note->n_type = 0; 504 return PTR_ADD(ptr, sizeof(Elf64_Nhdr)); 505 } 506 507 /* 508 * Initialize ELF header (new kernel) 509 */ 510 static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt) 511 { 512 memset(ehdr, 0, sizeof(*ehdr)); 513 memcpy(ehdr->e_ident, ELFMAG, SELFMAG); 514 ehdr->e_ident[EI_CLASS] = ELFCLASS64; 515 ehdr->e_ident[EI_DATA] = ELFDATA2MSB; 516 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 517 memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); 518 ehdr->e_type = ET_CORE; 519 ehdr->e_machine = EM_S390; 520 ehdr->e_version = EV_CURRENT; 521 ehdr->e_phoff = sizeof(Elf64_Ehdr); 522 ehdr->e_ehsize = sizeof(Elf64_Ehdr); 523 ehdr->e_phentsize = sizeof(Elf64_Phdr); 524 ehdr->e_phnum = mem_chunk_cnt + 1; 525 return ehdr + 1; 526 } 527 528 /* 529 * Return CPU count for ELF header (new kernel) 530 */ 531 static int get_cpu_cnt(void) 532 { 533 struct save_area *sa; 534 int cpus = 0; 535 536 list_for_each_entry(sa, &dump_save_areas, list) 537 if (sa->prefix != 0) 538 cpus++; 539 return cpus; 540 } 541 542 /* 543 * Return memory chunk count for ELF header (new kernel) 544 */ 545 static int get_mem_chunk_cnt(void) 546 { 547 int cnt = 0; 548 u64 idx; 549 550 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 551 MEMBLOCK_NONE, NULL, NULL, NULL) 552 cnt++; 553 return cnt; 554 } 555 556 /* 557 * Initialize ELF loads (new kernel) 558 */ 559 static void loads_init(Elf64_Phdr *phdr, u64 loads_offset) 560 { 561 phys_addr_t start, end; 562 u64 idx; 563 564 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 565 MEMBLOCK_NONE, &start, &end, NULL) { 566 phdr->p_filesz = end - start; 567 phdr->p_type = PT_LOAD; 568 phdr->p_offset = start; 569 phdr->p_vaddr = start; 570 phdr->p_paddr = start; 571 phdr->p_memsz = end - start; 572 phdr->p_flags = PF_R | PF_W | PF_X; 573 phdr->p_align = PAGE_SIZE; 574 phdr++; 575 } 576 } 577 578 /* 579 * Initialize notes (new kernel) 580 */ 581 static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) 582 { 583 struct save_area *sa; 584 void *ptr_start = ptr; 585 int cpu; 586 587 ptr = nt_prpsinfo(ptr); 588 589 cpu = 1; 590 list_for_each_entry(sa, &dump_save_areas, list) 591 if (sa->prefix != 0) 592 ptr = fill_cpu_elf_notes(ptr, cpu++, sa); 593 ptr = nt_vmcoreinfo(ptr); 594 ptr = nt_final(ptr); 595 memset(phdr, 0, sizeof(*phdr)); 596 phdr->p_type = PT_NOTE; 597 phdr->p_offset = notes_offset; 598 phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start); 599 phdr->p_memsz = phdr->p_filesz; 600 return ptr; 601 } 602 603 static size_t get_elfcorehdr_size(int mem_chunk_cnt) 604 { 605 size_t size; 606 607 size = sizeof(Elf64_Ehdr); 608 /* PT_NOTES */ 609 size += sizeof(Elf64_Phdr); 610 /* nt_prpsinfo */ 611 size += nt_size(NT_PRPSINFO, sizeof(struct elf_prpsinfo)); 612 /* regsets */ 613 size += get_cpu_cnt() * get_cpu_elf_notes_size(); 614 /* nt_vmcoreinfo */ 615 size += nt_vmcoreinfo_size(); 616 /* nt_final */ 617 size += sizeof(Elf64_Nhdr); 618 /* PT_LOADS */ 619 size += mem_chunk_cnt * sizeof(Elf64_Phdr); 620 621 return size; 622 } 623 624 /* 625 * Create ELF core header (new kernel) 626 */ 627 int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) 628 { 629 Elf64_Phdr *phdr_notes, *phdr_loads; 630 int mem_chunk_cnt; 631 void *ptr, *hdr; 632 u32 alloc_size; 633 u64 hdr_off; 634 635 /* If we are not in kdump or zfcpdump mode return */ 636 if (!OLDMEM_BASE && ipl_info.type != IPL_TYPE_FCP_DUMP) 637 return 0; 638 /* If we cannot get HSA size for zfcpdump return error */ 639 if (ipl_info.type == IPL_TYPE_FCP_DUMP && !sclp.hsa_size) 640 return -ENODEV; 641 642 /* For kdump, exclude previous crashkernel memory */ 643 if (OLDMEM_BASE) { 644 oldmem_region.base = OLDMEM_BASE; 645 oldmem_region.size = OLDMEM_SIZE; 646 oldmem_type.total_size = OLDMEM_SIZE; 647 } 648 649 mem_chunk_cnt = get_mem_chunk_cnt(); 650 651 alloc_size = get_elfcorehdr_size(mem_chunk_cnt); 652 653 hdr = kzalloc(alloc_size, GFP_KERNEL); 654 655 /* Without elfcorehdr /proc/vmcore cannot be created. Thus creating 656 * a dump with this crash kernel will fail. Panic now to allow other 657 * dump mechanisms to take over. 658 */ 659 if (!hdr) 660 panic("s390 kdump allocating elfcorehdr failed"); 661 662 /* Init elf header */ 663 ptr = ehdr_init(hdr, mem_chunk_cnt); 664 /* Init program headers */ 665 phdr_notes = ptr; 666 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr)); 667 phdr_loads = ptr; 668 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt); 669 /* Init notes */ 670 hdr_off = PTR_DIFF(ptr, hdr); 671 ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off); 672 /* Init loads */ 673 hdr_off = PTR_DIFF(ptr, hdr); 674 loads_init(phdr_loads, hdr_off); 675 *addr = (unsigned long long) hdr; 676 *size = (unsigned long long) hdr_off; 677 BUG_ON(elfcorehdr_size > alloc_size); 678 return 0; 679 } 680 681 /* 682 * Free ELF core header (new kernel) 683 */ 684 void elfcorehdr_free(unsigned long long addr) 685 { 686 kfree((void *)(unsigned long)addr); 687 } 688 689 /* 690 * Read from ELF header 691 */ 692 ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) 693 { 694 void *src = (void *)(unsigned long)*ppos; 695 696 memcpy(buf, src, count); 697 *ppos += count; 698 return count; 699 } 700 701 /* 702 * Read from ELF notes data 703 */ 704 ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) 705 { 706 void *src = (void *)(unsigned long)*ppos; 707 708 memcpy(buf, src, count); 709 *ppos += count; 710 return count; 711 } 712