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/memblock.h> 17 #include <linux/elf.h> 18 #include <asm/asm-offsets.h> 19 #include <asm/os_info.h> 20 #include <asm/elf.h> 21 #include <asm/ipl.h> 22 #include <asm/sclp.h> 23 24 #define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y))) 25 #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y))) 26 #define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y)))) 27 28 static struct memblock_region oldmem_region; 29 30 static struct memblock_type oldmem_type = { 31 .cnt = 1, 32 .max = 1, 33 .total_size = 0, 34 .regions = &oldmem_region, 35 .name = "oldmem", 36 }; 37 38 struct save_area { 39 struct list_head list; 40 u64 psw[2]; 41 u64 ctrs[16]; 42 u64 gprs[16]; 43 u32 acrs[16]; 44 u64 fprs[16]; 45 u32 fpc; 46 u32 prefix; 47 u64 todpreg; 48 u64 timer; 49 u64 todcmp; 50 u64 vxrs_low[16]; 51 __vector128 vxrs_high[16]; 52 }; 53 54 static LIST_HEAD(dump_save_areas); 55 56 /* 57 * Allocate a save area 58 */ 59 struct save_area * __init save_area_alloc(bool is_boot_cpu) 60 { 61 struct save_area *sa; 62 63 sa = (void *) memblock_phys_alloc(sizeof(*sa), 8); 64 if (!sa) 65 panic("Failed to allocate save area\n"); 66 67 if (is_boot_cpu) 68 list_add(&sa->list, &dump_save_areas); 69 else 70 list_add_tail(&sa->list, &dump_save_areas); 71 return sa; 72 } 73 74 /* 75 * Return the address of the save area for the boot CPU 76 */ 77 struct save_area * __init save_area_boot_cpu(void) 78 { 79 return list_first_entry_or_null(&dump_save_areas, struct save_area, list); 80 } 81 82 /* 83 * Copy CPU registers into the save area 84 */ 85 void __init save_area_add_regs(struct save_area *sa, void *regs) 86 { 87 struct lowcore *lc; 88 89 lc = (struct lowcore *)(regs - __LC_FPREGS_SAVE_AREA); 90 memcpy(&sa->psw, &lc->psw_save_area, sizeof(sa->psw)); 91 memcpy(&sa->ctrs, &lc->cregs_save_area, sizeof(sa->ctrs)); 92 memcpy(&sa->gprs, &lc->gpregs_save_area, sizeof(sa->gprs)); 93 memcpy(&sa->acrs, &lc->access_regs_save_area, sizeof(sa->acrs)); 94 memcpy(&sa->fprs, &lc->floating_pt_save_area, sizeof(sa->fprs)); 95 memcpy(&sa->fpc, &lc->fpt_creg_save_area, sizeof(sa->fpc)); 96 memcpy(&sa->prefix, &lc->prefixreg_save_area, sizeof(sa->prefix)); 97 memcpy(&sa->todpreg, &lc->tod_progreg_save_area, sizeof(sa->todpreg)); 98 memcpy(&sa->timer, &lc->cpu_timer_save_area, sizeof(sa->timer)); 99 memcpy(&sa->todcmp, &lc->clock_comp_save_area, sizeof(sa->todcmp)); 100 } 101 102 /* 103 * Copy vector registers into the save area 104 */ 105 void __init save_area_add_vxrs(struct save_area *sa, __vector128 *vxrs) 106 { 107 int i; 108 109 /* Copy lower halves of vector registers 0-15 */ 110 for (i = 0; i < 16; i++) 111 memcpy(&sa->vxrs_low[i], &vxrs[i].u[2], 8); 112 /* Copy vector registers 16-31 */ 113 memcpy(sa->vxrs_high, vxrs + 16, 16 * sizeof(__vector128)); 114 } 115 116 /* 117 * Return physical address for virtual address 118 */ 119 static inline void *load_real_addr(void *addr) 120 { 121 unsigned long real_addr; 122 123 asm volatile( 124 " lra %0,0(%1)\n" 125 " jz 0f\n" 126 " la %0,0\n" 127 "0:" 128 : "=a" (real_addr) : "a" (addr) : "cc"); 129 return (void *)real_addr; 130 } 131 132 /* 133 * Copy memory of the old, dumped system to a kernel space virtual address 134 */ 135 int copy_oldmem_kernel(void *dst, void *src, size_t count) 136 { 137 unsigned long from, len; 138 void *ra; 139 int rc; 140 141 while (count) { 142 from = __pa(src); 143 if (!OLDMEM_BASE && from < sclp.hsa_size) { 144 /* Copy from zfcpdump HSA area */ 145 len = min(count, sclp.hsa_size - from); 146 rc = memcpy_hsa_kernel(dst, from, len); 147 if (rc) 148 return rc; 149 } else { 150 /* Check for swapped kdump oldmem areas */ 151 if (OLDMEM_BASE && from - OLDMEM_BASE < OLDMEM_SIZE) { 152 from -= OLDMEM_BASE; 153 len = min(count, OLDMEM_SIZE - from); 154 } else if (OLDMEM_BASE && from < OLDMEM_SIZE) { 155 len = min(count, OLDMEM_SIZE - from); 156 from += OLDMEM_BASE; 157 } else { 158 len = count; 159 } 160 if (is_vmalloc_or_module_addr(dst)) { 161 ra = load_real_addr(dst); 162 len = min(PAGE_SIZE - offset_in_page(ra), len); 163 } else { 164 ra = dst; 165 } 166 if (memcpy_real(ra, (void *) from, len)) 167 return -EFAULT; 168 } 169 dst += len; 170 src += len; 171 count -= len; 172 } 173 return 0; 174 } 175 176 /* 177 * Copy memory of the old, dumped system to a user space virtual address 178 */ 179 static int copy_oldmem_user(void __user *dst, void *src, size_t count) 180 { 181 unsigned long from, len; 182 int rc; 183 184 while (count) { 185 from = __pa(src); 186 if (!OLDMEM_BASE && from < sclp.hsa_size) { 187 /* Copy from zfcpdump HSA area */ 188 len = min(count, sclp.hsa_size - from); 189 rc = memcpy_hsa_user(dst, from, len); 190 if (rc) 191 return rc; 192 } else { 193 /* Check for swapped kdump oldmem areas */ 194 if (OLDMEM_BASE && from - OLDMEM_BASE < OLDMEM_SIZE) { 195 from -= OLDMEM_BASE; 196 len = min(count, OLDMEM_SIZE - from); 197 } else if (OLDMEM_BASE && from < OLDMEM_SIZE) { 198 len = min(count, OLDMEM_SIZE - from); 199 from += OLDMEM_BASE; 200 } else { 201 len = count; 202 } 203 rc = copy_to_user_real(dst, (void *) from, count); 204 if (rc) 205 return rc; 206 } 207 dst += len; 208 src += len; 209 count -= len; 210 } 211 return 0; 212 } 213 214 /* 215 * Copy one page from "oldmem" 216 */ 217 ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, 218 unsigned long offset, int userbuf) 219 { 220 void *src; 221 int rc; 222 223 if (!csize) 224 return 0; 225 src = (void *) (pfn << PAGE_SHIFT) + offset; 226 if (userbuf) 227 rc = copy_oldmem_user((void __force __user *) buf, src, csize); 228 else 229 rc = copy_oldmem_kernel((void *) buf, src, csize); 230 return rc; 231 } 232 233 /* 234 * Remap "oldmem" for kdump 235 * 236 * For the kdump reserved memory this functions performs a swap operation: 237 * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] 238 */ 239 static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma, 240 unsigned long from, unsigned long pfn, 241 unsigned long size, pgprot_t prot) 242 { 243 unsigned long size_old; 244 int rc; 245 246 if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) { 247 size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT)); 248 rc = remap_pfn_range(vma, from, 249 pfn + (OLDMEM_BASE >> PAGE_SHIFT), 250 size_old, prot); 251 if (rc || size == size_old) 252 return rc; 253 size -= size_old; 254 from += size_old; 255 pfn += size_old >> PAGE_SHIFT; 256 } 257 return remap_pfn_range(vma, from, pfn, size, prot); 258 } 259 260 /* 261 * Remap "oldmem" for zfcpdump 262 * 263 * We only map available memory above HSA size. Memory below HSA size 264 * is read on demand using the copy_oldmem_page() function. 265 */ 266 static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma, 267 unsigned long from, 268 unsigned long pfn, 269 unsigned long size, pgprot_t prot) 270 { 271 unsigned long hsa_end = sclp.hsa_size; 272 unsigned long size_hsa; 273 274 if (pfn < hsa_end >> PAGE_SHIFT) { 275 size_hsa = min(size, hsa_end - (pfn << PAGE_SHIFT)); 276 if (size == size_hsa) 277 return 0; 278 size -= size_hsa; 279 from += size_hsa; 280 pfn += size_hsa >> PAGE_SHIFT; 281 } 282 return remap_pfn_range(vma, from, pfn, size, prot); 283 } 284 285 /* 286 * Remap "oldmem" for kdump or zfcpdump 287 */ 288 int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from, 289 unsigned long pfn, unsigned long size, pgprot_t prot) 290 { 291 if (OLDMEM_BASE) 292 return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot); 293 else 294 return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size, 295 prot); 296 } 297 298 static const char *nt_name(Elf64_Word type) 299 { 300 const char *name = "LINUX"; 301 302 if (type == NT_PRPSINFO || type == NT_PRSTATUS || type == NT_PRFPREG) 303 name = KEXEC_CORE_NOTE_NAME; 304 return name; 305 } 306 307 /* 308 * Initialize ELF note 309 */ 310 static void *nt_init_name(void *buf, Elf64_Word type, void *desc, int d_len, 311 const char *name) 312 { 313 Elf64_Nhdr *note; 314 u64 len; 315 316 note = (Elf64_Nhdr *)buf; 317 note->n_namesz = strlen(name) + 1; 318 note->n_descsz = d_len; 319 note->n_type = type; 320 len = sizeof(Elf64_Nhdr); 321 322 memcpy(buf + len, name, note->n_namesz); 323 len = roundup(len + note->n_namesz, 4); 324 325 memcpy(buf + len, desc, note->n_descsz); 326 len = roundup(len + note->n_descsz, 4); 327 328 return PTR_ADD(buf, len); 329 } 330 331 static inline void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len) 332 { 333 return nt_init_name(buf, type, desc, d_len, nt_name(type)); 334 } 335 336 /* 337 * Calculate the size of ELF note 338 */ 339 static size_t nt_size_name(int d_len, const char *name) 340 { 341 size_t size; 342 343 size = sizeof(Elf64_Nhdr); 344 size += roundup(strlen(name) + 1, 4); 345 size += roundup(d_len, 4); 346 347 return size; 348 } 349 350 static inline size_t nt_size(Elf64_Word type, int d_len) 351 { 352 return nt_size_name(d_len, nt_name(type)); 353 } 354 355 /* 356 * Fill ELF notes for one CPU with save area registers 357 */ 358 static void *fill_cpu_elf_notes(void *ptr, int cpu, struct save_area *sa) 359 { 360 struct elf_prstatus nt_prstatus; 361 elf_fpregset_t nt_fpregset; 362 363 /* Prepare prstatus note */ 364 memset(&nt_prstatus, 0, sizeof(nt_prstatus)); 365 memcpy(&nt_prstatus.pr_reg.gprs, sa->gprs, sizeof(sa->gprs)); 366 memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw)); 367 memcpy(&nt_prstatus.pr_reg.acrs, sa->acrs, sizeof(sa->acrs)); 368 nt_prstatus.pr_pid = cpu; 369 /* Prepare fpregset (floating point) note */ 370 memset(&nt_fpregset, 0, sizeof(nt_fpregset)); 371 memcpy(&nt_fpregset.fpc, &sa->fpc, sizeof(sa->fpc)); 372 memcpy(&nt_fpregset.fprs, &sa->fprs, sizeof(sa->fprs)); 373 /* Create ELF notes for the CPU */ 374 ptr = nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus)); 375 ptr = nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset)); 376 ptr = nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer)); 377 ptr = nt_init(ptr, NT_S390_TODCMP, &sa->todcmp, sizeof(sa->todcmp)); 378 ptr = nt_init(ptr, NT_S390_TODPREG, &sa->todpreg, sizeof(sa->todpreg)); 379 ptr = nt_init(ptr, NT_S390_CTRS, &sa->ctrs, sizeof(sa->ctrs)); 380 ptr = nt_init(ptr, NT_S390_PREFIX, &sa->prefix, sizeof(sa->prefix)); 381 if (MACHINE_HAS_VX) { 382 ptr = nt_init(ptr, NT_S390_VXRS_HIGH, 383 &sa->vxrs_high, sizeof(sa->vxrs_high)); 384 ptr = nt_init(ptr, NT_S390_VXRS_LOW, 385 &sa->vxrs_low, sizeof(sa->vxrs_low)); 386 } 387 return ptr; 388 } 389 390 /* 391 * Calculate size of ELF notes per cpu 392 */ 393 static size_t get_cpu_elf_notes_size(void) 394 { 395 struct save_area *sa = NULL; 396 size_t size; 397 398 size = nt_size(NT_PRSTATUS, sizeof(struct elf_prstatus)); 399 size += nt_size(NT_PRFPREG, sizeof(elf_fpregset_t)); 400 size += nt_size(NT_S390_TIMER, sizeof(sa->timer)); 401 size += nt_size(NT_S390_TODCMP, sizeof(sa->todcmp)); 402 size += nt_size(NT_S390_TODPREG, sizeof(sa->todpreg)); 403 size += nt_size(NT_S390_CTRS, sizeof(sa->ctrs)); 404 size += nt_size(NT_S390_PREFIX, sizeof(sa->prefix)); 405 if (MACHINE_HAS_VX) { 406 size += nt_size(NT_S390_VXRS_HIGH, sizeof(sa->vxrs_high)); 407 size += nt_size(NT_S390_VXRS_LOW, sizeof(sa->vxrs_low)); 408 } 409 410 return size; 411 } 412 413 /* 414 * Initialize prpsinfo note (new kernel) 415 */ 416 static void *nt_prpsinfo(void *ptr) 417 { 418 struct elf_prpsinfo prpsinfo; 419 420 memset(&prpsinfo, 0, sizeof(prpsinfo)); 421 prpsinfo.pr_sname = 'R'; 422 strcpy(prpsinfo.pr_fname, "vmlinux"); 423 return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo)); 424 } 425 426 /* 427 * Get vmcoreinfo using lowcore->vmcore_info (new kernel) 428 */ 429 static void *get_vmcoreinfo_old(unsigned long *size) 430 { 431 char nt_name[11], *vmcoreinfo; 432 Elf64_Nhdr note; 433 void *addr; 434 435 if (copy_oldmem_kernel(&addr, &S390_lowcore.vmcore_info, sizeof(addr))) 436 return NULL; 437 memset(nt_name, 0, sizeof(nt_name)); 438 if (copy_oldmem_kernel(¬e, addr, sizeof(note))) 439 return NULL; 440 if (copy_oldmem_kernel(nt_name, addr + sizeof(note), 441 sizeof(nt_name) - 1)) 442 return NULL; 443 if (strcmp(nt_name, VMCOREINFO_NOTE_NAME) != 0) 444 return NULL; 445 vmcoreinfo = kzalloc(note.n_descsz, GFP_KERNEL); 446 if (!vmcoreinfo) 447 return NULL; 448 if (copy_oldmem_kernel(vmcoreinfo, addr + 24, note.n_descsz)) { 449 kfree(vmcoreinfo); 450 return NULL; 451 } 452 *size = note.n_descsz; 453 return vmcoreinfo; 454 } 455 456 /* 457 * Initialize vmcoreinfo note (new kernel) 458 */ 459 static void *nt_vmcoreinfo(void *ptr) 460 { 461 const char *name = VMCOREINFO_NOTE_NAME; 462 unsigned long size; 463 void *vmcoreinfo; 464 465 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 466 if (vmcoreinfo) 467 return nt_init_name(ptr, 0, vmcoreinfo, size, name); 468 469 vmcoreinfo = get_vmcoreinfo_old(&size); 470 if (!vmcoreinfo) 471 return ptr; 472 ptr = nt_init_name(ptr, 0, vmcoreinfo, size, name); 473 kfree(vmcoreinfo); 474 return ptr; 475 } 476 477 static size_t nt_vmcoreinfo_size(void) 478 { 479 const char *name = VMCOREINFO_NOTE_NAME; 480 unsigned long size; 481 void *vmcoreinfo; 482 483 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 484 if (vmcoreinfo) 485 return nt_size_name(size, name); 486 487 vmcoreinfo = get_vmcoreinfo_old(&size); 488 if (!vmcoreinfo) 489 return 0; 490 491 kfree(vmcoreinfo); 492 return nt_size_name(size, name); 493 } 494 495 /* 496 * Initialize final note (needed for /proc/vmcore code) 497 */ 498 static void *nt_final(void *ptr) 499 { 500 Elf64_Nhdr *note; 501 502 note = (Elf64_Nhdr *) ptr; 503 note->n_namesz = 0; 504 note->n_descsz = 0; 505 note->n_type = 0; 506 return PTR_ADD(ptr, sizeof(Elf64_Nhdr)); 507 } 508 509 /* 510 * Initialize ELF header (new kernel) 511 */ 512 static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt) 513 { 514 memset(ehdr, 0, sizeof(*ehdr)); 515 memcpy(ehdr->e_ident, ELFMAG, SELFMAG); 516 ehdr->e_ident[EI_CLASS] = ELFCLASS64; 517 ehdr->e_ident[EI_DATA] = ELFDATA2MSB; 518 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 519 memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); 520 ehdr->e_type = ET_CORE; 521 ehdr->e_machine = EM_S390; 522 ehdr->e_version = EV_CURRENT; 523 ehdr->e_phoff = sizeof(Elf64_Ehdr); 524 ehdr->e_ehsize = sizeof(Elf64_Ehdr); 525 ehdr->e_phentsize = sizeof(Elf64_Phdr); 526 ehdr->e_phnum = mem_chunk_cnt + 1; 527 return ehdr + 1; 528 } 529 530 /* 531 * Return CPU count for ELF header (new kernel) 532 */ 533 static int get_cpu_cnt(void) 534 { 535 struct save_area *sa; 536 int cpus = 0; 537 538 list_for_each_entry(sa, &dump_save_areas, list) 539 if (sa->prefix != 0) 540 cpus++; 541 return cpus; 542 } 543 544 /* 545 * Return memory chunk count for ELF header (new kernel) 546 */ 547 static int get_mem_chunk_cnt(void) 548 { 549 int cnt = 0; 550 u64 idx; 551 552 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 553 MEMBLOCK_NONE, NULL, NULL, NULL) 554 cnt++; 555 return cnt; 556 } 557 558 /* 559 * Initialize ELF loads (new kernel) 560 */ 561 static void loads_init(Elf64_Phdr *phdr, u64 loads_offset) 562 { 563 phys_addr_t start, end; 564 u64 idx; 565 566 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 567 MEMBLOCK_NONE, &start, &end, NULL) { 568 phdr->p_filesz = end - start; 569 phdr->p_type = PT_LOAD; 570 phdr->p_offset = start; 571 phdr->p_vaddr = start; 572 phdr->p_paddr = start; 573 phdr->p_memsz = end - start; 574 phdr->p_flags = PF_R | PF_W | PF_X; 575 phdr->p_align = PAGE_SIZE; 576 phdr++; 577 } 578 } 579 580 /* 581 * Initialize notes (new kernel) 582 */ 583 static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) 584 { 585 struct save_area *sa; 586 void *ptr_start = ptr; 587 int cpu; 588 589 ptr = nt_prpsinfo(ptr); 590 591 cpu = 1; 592 list_for_each_entry(sa, &dump_save_areas, list) 593 if (sa->prefix != 0) 594 ptr = fill_cpu_elf_notes(ptr, cpu++, sa); 595 ptr = nt_vmcoreinfo(ptr); 596 ptr = nt_final(ptr); 597 memset(phdr, 0, sizeof(*phdr)); 598 phdr->p_type = PT_NOTE; 599 phdr->p_offset = notes_offset; 600 phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start); 601 phdr->p_memsz = phdr->p_filesz; 602 return ptr; 603 } 604 605 static size_t get_elfcorehdr_size(int mem_chunk_cnt) 606 { 607 size_t size; 608 609 size = sizeof(Elf64_Ehdr); 610 /* PT_NOTES */ 611 size += sizeof(Elf64_Phdr); 612 /* nt_prpsinfo */ 613 size += nt_size(NT_PRPSINFO, sizeof(struct elf_prpsinfo)); 614 /* regsets */ 615 size += get_cpu_cnt() * get_cpu_elf_notes_size(); 616 /* nt_vmcoreinfo */ 617 size += nt_vmcoreinfo_size(); 618 /* nt_final */ 619 size += sizeof(Elf64_Nhdr); 620 /* PT_LOADS */ 621 size += mem_chunk_cnt * sizeof(Elf64_Phdr); 622 623 return size; 624 } 625 626 /* 627 * Create ELF core header (new kernel) 628 */ 629 int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) 630 { 631 Elf64_Phdr *phdr_notes, *phdr_loads; 632 int mem_chunk_cnt; 633 void *ptr, *hdr; 634 u32 alloc_size; 635 u64 hdr_off; 636 637 /* If we are not in kdump or zfcpdump mode return */ 638 if (!OLDMEM_BASE && ipl_info.type != IPL_TYPE_FCP_DUMP) 639 return 0; 640 /* If we cannot get HSA size for zfcpdump return error */ 641 if (ipl_info.type == IPL_TYPE_FCP_DUMP && !sclp.hsa_size) 642 return -ENODEV; 643 644 /* For kdump, exclude previous crashkernel memory */ 645 if (OLDMEM_BASE) { 646 oldmem_region.base = OLDMEM_BASE; 647 oldmem_region.size = OLDMEM_SIZE; 648 oldmem_type.total_size = OLDMEM_SIZE; 649 } 650 651 mem_chunk_cnt = get_mem_chunk_cnt(); 652 653 alloc_size = get_elfcorehdr_size(mem_chunk_cnt); 654 655 hdr = kzalloc(alloc_size, GFP_KERNEL); 656 657 /* Without elfcorehdr /proc/vmcore cannot be created. Thus creating 658 * a dump with this crash kernel will fail. Panic now to allow other 659 * dump mechanisms to take over. 660 */ 661 if (!hdr) 662 panic("s390 kdump allocating elfcorehdr failed"); 663 664 /* Init elf header */ 665 ptr = ehdr_init(hdr, mem_chunk_cnt); 666 /* Init program headers */ 667 phdr_notes = ptr; 668 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr)); 669 phdr_loads = ptr; 670 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt); 671 /* Init notes */ 672 hdr_off = PTR_DIFF(ptr, hdr); 673 ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off); 674 /* Init loads */ 675 hdr_off = PTR_DIFF(ptr, hdr); 676 loads_init(phdr_loads, hdr_off); 677 *addr = (unsigned long long) hdr; 678 *size = (unsigned long long) hdr_off; 679 BUG_ON(elfcorehdr_size > alloc_size); 680 return 0; 681 } 682 683 /* 684 * Free ELF core header (new kernel) 685 */ 686 void elfcorehdr_free(unsigned long long addr) 687 { 688 kfree((void *)(unsigned long)addr); 689 } 690 691 /* 692 * Read from ELF header 693 */ 694 ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) 695 { 696 void *src = (void *)(unsigned long)*ppos; 697 698 memcpy(buf, src, count); 699 *ppos += count; 700 return count; 701 } 702 703 /* 704 * Read from ELF notes data 705 */ 706 ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) 707 { 708 void *src = (void *)(unsigned long)*ppos; 709 710 memcpy(buf, src, count); 711 *ppos += count; 712 return count; 713 } 714