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 /* 297 * Alloc memory and panic in case of ENOMEM 298 */ 299 static void *kzalloc_panic(int len) 300 { 301 void *rc; 302 303 rc = kzalloc(len, GFP_KERNEL); 304 if (!rc) 305 panic("s390 kdump kzalloc (%d) failed", len); 306 return rc; 307 } 308 309 static const char *nt_name(Elf64_Word type) 310 { 311 const char *name = "LINUX"; 312 313 if (type == NT_PRPSINFO || type == NT_PRSTATUS || type == NT_PRFPREG) 314 name = KEXEC_CORE_NOTE_NAME; 315 return name; 316 } 317 318 /* 319 * Initialize ELF note 320 */ 321 static void *nt_init_name(void *buf, Elf64_Word type, void *desc, int d_len, 322 const char *name) 323 { 324 Elf64_Nhdr *note; 325 u64 len; 326 327 note = (Elf64_Nhdr *)buf; 328 note->n_namesz = strlen(name) + 1; 329 note->n_descsz = d_len; 330 note->n_type = type; 331 len = sizeof(Elf64_Nhdr); 332 333 memcpy(buf + len, name, note->n_namesz); 334 len = roundup(len + note->n_namesz, 4); 335 336 memcpy(buf + len, desc, note->n_descsz); 337 len = roundup(len + note->n_descsz, 4); 338 339 return PTR_ADD(buf, len); 340 } 341 342 static inline void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len) 343 { 344 return nt_init_name(buf, type, desc, d_len, nt_name(type)); 345 } 346 347 /* 348 * Calculate the size of ELF note 349 */ 350 static size_t nt_size_name(int d_len, const char *name) 351 { 352 size_t size; 353 354 size = sizeof(Elf64_Nhdr); 355 size += roundup(strlen(name) + 1, 4); 356 size += roundup(d_len, 4); 357 358 return size; 359 } 360 361 static inline size_t nt_size(Elf64_Word type, int d_len) 362 { 363 return nt_size_name(d_len, nt_name(type)); 364 } 365 366 /* 367 * Fill ELF notes for one CPU with save area registers 368 */ 369 static void *fill_cpu_elf_notes(void *ptr, int cpu, struct save_area *sa) 370 { 371 struct elf_prstatus nt_prstatus; 372 elf_fpregset_t nt_fpregset; 373 374 /* Prepare prstatus note */ 375 memset(&nt_prstatus, 0, sizeof(nt_prstatus)); 376 memcpy(&nt_prstatus.pr_reg.gprs, sa->gprs, sizeof(sa->gprs)); 377 memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw)); 378 memcpy(&nt_prstatus.pr_reg.acrs, sa->acrs, sizeof(sa->acrs)); 379 nt_prstatus.pr_pid = cpu; 380 /* Prepare fpregset (floating point) note */ 381 memset(&nt_fpregset, 0, sizeof(nt_fpregset)); 382 memcpy(&nt_fpregset.fpc, &sa->fpc, sizeof(sa->fpc)); 383 memcpy(&nt_fpregset.fprs, &sa->fprs, sizeof(sa->fprs)); 384 /* Create ELF notes for the CPU */ 385 ptr = nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus)); 386 ptr = nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset)); 387 ptr = nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer)); 388 ptr = nt_init(ptr, NT_S390_TODCMP, &sa->todcmp, sizeof(sa->todcmp)); 389 ptr = nt_init(ptr, NT_S390_TODPREG, &sa->todpreg, sizeof(sa->todpreg)); 390 ptr = nt_init(ptr, NT_S390_CTRS, &sa->ctrs, sizeof(sa->ctrs)); 391 ptr = nt_init(ptr, NT_S390_PREFIX, &sa->prefix, sizeof(sa->prefix)); 392 if (MACHINE_HAS_VX) { 393 ptr = nt_init(ptr, NT_S390_VXRS_HIGH, 394 &sa->vxrs_high, sizeof(sa->vxrs_high)); 395 ptr = nt_init(ptr, NT_S390_VXRS_LOW, 396 &sa->vxrs_low, sizeof(sa->vxrs_low)); 397 } 398 return ptr; 399 } 400 401 /* 402 * Calculate size of ELF notes per cpu 403 */ 404 static size_t get_cpu_elf_notes_size(void) 405 { 406 struct save_area *sa = NULL; 407 size_t size; 408 409 size = nt_size(NT_PRSTATUS, sizeof(struct elf_prstatus)); 410 size += nt_size(NT_PRFPREG, sizeof(elf_fpregset_t)); 411 size += nt_size(NT_S390_TIMER, sizeof(sa->timer)); 412 size += nt_size(NT_S390_TODCMP, sizeof(sa->todcmp)); 413 size += nt_size(NT_S390_TODPREG, sizeof(sa->todpreg)); 414 size += nt_size(NT_S390_CTRS, sizeof(sa->ctrs)); 415 size += nt_size(NT_S390_PREFIX, sizeof(sa->prefix)); 416 if (MACHINE_HAS_VX) { 417 size += nt_size(NT_S390_VXRS_HIGH, sizeof(sa->vxrs_high)); 418 size += nt_size(NT_S390_VXRS_LOW, sizeof(sa->vxrs_low)); 419 } 420 421 return size; 422 } 423 424 /* 425 * Initialize prpsinfo note (new kernel) 426 */ 427 static void *nt_prpsinfo(void *ptr) 428 { 429 struct elf_prpsinfo prpsinfo; 430 431 memset(&prpsinfo, 0, sizeof(prpsinfo)); 432 prpsinfo.pr_sname = 'R'; 433 strcpy(prpsinfo.pr_fname, "vmlinux"); 434 return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo)); 435 } 436 437 /* 438 * Get vmcoreinfo using lowcore->vmcore_info (new kernel) 439 */ 440 static void *get_vmcoreinfo_old(unsigned long *size) 441 { 442 char nt_name[11], *vmcoreinfo; 443 Elf64_Nhdr note; 444 void *addr; 445 446 if (copy_oldmem_kernel(&addr, &S390_lowcore.vmcore_info, sizeof(addr))) 447 return NULL; 448 memset(nt_name, 0, sizeof(nt_name)); 449 if (copy_oldmem_kernel(¬e, addr, sizeof(note))) 450 return NULL; 451 if (copy_oldmem_kernel(nt_name, addr + sizeof(note), 452 sizeof(nt_name) - 1)) 453 return NULL; 454 if (strcmp(nt_name, VMCOREINFO_NOTE_NAME) != 0) 455 return NULL; 456 vmcoreinfo = kzalloc_panic(note.n_descsz); 457 if (copy_oldmem_kernel(vmcoreinfo, addr + 24, note.n_descsz)) { 458 kfree(vmcoreinfo); 459 return NULL; 460 } 461 *size = note.n_descsz; 462 return vmcoreinfo; 463 } 464 465 /* 466 * Initialize vmcoreinfo note (new kernel) 467 */ 468 static void *nt_vmcoreinfo(void *ptr) 469 { 470 const char *name = VMCOREINFO_NOTE_NAME; 471 unsigned long size; 472 void *vmcoreinfo; 473 474 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 475 if (vmcoreinfo) 476 return nt_init_name(ptr, 0, vmcoreinfo, size, name); 477 478 vmcoreinfo = get_vmcoreinfo_old(&size); 479 if (!vmcoreinfo) 480 return ptr; 481 ptr = nt_init_name(ptr, 0, vmcoreinfo, size, name); 482 kfree(vmcoreinfo); 483 return ptr; 484 } 485 486 static size_t nt_vmcoreinfo_size(void) 487 { 488 const char *name = VMCOREINFO_NOTE_NAME; 489 unsigned long size; 490 void *vmcoreinfo; 491 492 vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size); 493 if (vmcoreinfo) 494 return nt_size_name(size, name); 495 496 vmcoreinfo = get_vmcoreinfo_old(&size); 497 if (!vmcoreinfo) 498 return 0; 499 500 kfree(vmcoreinfo); 501 return nt_size_name(size, name); 502 } 503 504 /* 505 * Initialize final note (needed for /proc/vmcore code) 506 */ 507 static void *nt_final(void *ptr) 508 { 509 Elf64_Nhdr *note; 510 511 note = (Elf64_Nhdr *) ptr; 512 note->n_namesz = 0; 513 note->n_descsz = 0; 514 note->n_type = 0; 515 return PTR_ADD(ptr, sizeof(Elf64_Nhdr)); 516 } 517 518 /* 519 * Initialize ELF header (new kernel) 520 */ 521 static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt) 522 { 523 memset(ehdr, 0, sizeof(*ehdr)); 524 memcpy(ehdr->e_ident, ELFMAG, SELFMAG); 525 ehdr->e_ident[EI_CLASS] = ELFCLASS64; 526 ehdr->e_ident[EI_DATA] = ELFDATA2MSB; 527 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 528 memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); 529 ehdr->e_type = ET_CORE; 530 ehdr->e_machine = EM_S390; 531 ehdr->e_version = EV_CURRENT; 532 ehdr->e_phoff = sizeof(Elf64_Ehdr); 533 ehdr->e_ehsize = sizeof(Elf64_Ehdr); 534 ehdr->e_phentsize = sizeof(Elf64_Phdr); 535 ehdr->e_phnum = mem_chunk_cnt + 1; 536 return ehdr + 1; 537 } 538 539 /* 540 * Return CPU count for ELF header (new kernel) 541 */ 542 static int get_cpu_cnt(void) 543 { 544 struct save_area *sa; 545 int cpus = 0; 546 547 list_for_each_entry(sa, &dump_save_areas, list) 548 if (sa->prefix != 0) 549 cpus++; 550 return cpus; 551 } 552 553 /* 554 * Return memory chunk count for ELF header (new kernel) 555 */ 556 static int get_mem_chunk_cnt(void) 557 { 558 int cnt = 0; 559 u64 idx; 560 561 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 562 MEMBLOCK_NONE, NULL, NULL, NULL) 563 cnt++; 564 return cnt; 565 } 566 567 /* 568 * Initialize ELF loads (new kernel) 569 */ 570 static void loads_init(Elf64_Phdr *phdr, u64 loads_offset) 571 { 572 phys_addr_t start, end; 573 u64 idx; 574 575 for_each_mem_range(idx, &memblock.physmem, &oldmem_type, NUMA_NO_NODE, 576 MEMBLOCK_NONE, &start, &end, NULL) { 577 phdr->p_filesz = end - start; 578 phdr->p_type = PT_LOAD; 579 phdr->p_offset = start; 580 phdr->p_vaddr = start; 581 phdr->p_paddr = start; 582 phdr->p_memsz = end - start; 583 phdr->p_flags = PF_R | PF_W | PF_X; 584 phdr->p_align = PAGE_SIZE; 585 phdr++; 586 } 587 } 588 589 /* 590 * Initialize notes (new kernel) 591 */ 592 static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) 593 { 594 struct save_area *sa; 595 void *ptr_start = ptr; 596 int cpu; 597 598 ptr = nt_prpsinfo(ptr); 599 600 cpu = 1; 601 list_for_each_entry(sa, &dump_save_areas, list) 602 if (sa->prefix != 0) 603 ptr = fill_cpu_elf_notes(ptr, cpu++, sa); 604 ptr = nt_vmcoreinfo(ptr); 605 ptr = nt_final(ptr); 606 memset(phdr, 0, sizeof(*phdr)); 607 phdr->p_type = PT_NOTE; 608 phdr->p_offset = notes_offset; 609 phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start); 610 phdr->p_memsz = phdr->p_filesz; 611 return ptr; 612 } 613 614 static size_t get_elfcorehdr_size(int mem_chunk_cnt) 615 { 616 size_t size; 617 618 size = sizeof(Elf64_Ehdr); 619 /* PT_NOTES */ 620 size += sizeof(Elf64_Phdr); 621 /* nt_prpsinfo */ 622 size += nt_size(NT_PRPSINFO, sizeof(struct elf_prpsinfo)); 623 /* regsets */ 624 size += get_cpu_cnt() * get_cpu_elf_notes_size(); 625 /* nt_vmcoreinfo */ 626 size += nt_vmcoreinfo_size(); 627 /* nt_final */ 628 size += sizeof(Elf64_Nhdr); 629 /* PT_LOADS */ 630 size += mem_chunk_cnt * sizeof(Elf64_Phdr); 631 632 return size; 633 } 634 635 /* 636 * Create ELF core header (new kernel) 637 */ 638 int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) 639 { 640 Elf64_Phdr *phdr_notes, *phdr_loads; 641 int mem_chunk_cnt; 642 void *ptr, *hdr; 643 u32 alloc_size; 644 u64 hdr_off; 645 646 /* If we are not in kdump or zfcpdump mode return */ 647 if (!OLDMEM_BASE && ipl_info.type != IPL_TYPE_FCP_DUMP) 648 return 0; 649 /* If we cannot get HSA size for zfcpdump return error */ 650 if (ipl_info.type == IPL_TYPE_FCP_DUMP && !sclp.hsa_size) 651 return -ENODEV; 652 653 /* For kdump, exclude previous crashkernel memory */ 654 if (OLDMEM_BASE) { 655 oldmem_region.base = OLDMEM_BASE; 656 oldmem_region.size = OLDMEM_SIZE; 657 oldmem_type.total_size = OLDMEM_SIZE; 658 } 659 660 mem_chunk_cnt = get_mem_chunk_cnt(); 661 662 alloc_size = get_elfcorehdr_size(mem_chunk_cnt); 663 664 hdr = kzalloc_panic(alloc_size); 665 /* Init elf header */ 666 ptr = ehdr_init(hdr, mem_chunk_cnt); 667 /* Init program headers */ 668 phdr_notes = ptr; 669 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr)); 670 phdr_loads = ptr; 671 ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt); 672 /* Init notes */ 673 hdr_off = PTR_DIFF(ptr, hdr); 674 ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off); 675 /* Init loads */ 676 hdr_off = PTR_DIFF(ptr, hdr); 677 loads_init(phdr_loads, hdr_off); 678 *addr = (unsigned long long) hdr; 679 *size = (unsigned long long) hdr_off; 680 BUG_ON(elfcorehdr_size > alloc_size); 681 return 0; 682 } 683 684 /* 685 * Free ELF core header (new kernel) 686 */ 687 void elfcorehdr_free(unsigned long long addr) 688 { 689 kfree((void *)(unsigned long)addr); 690 } 691 692 /* 693 * Read from ELF header 694 */ 695 ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) 696 { 697 void *src = (void *)(unsigned long)*ppos; 698 699 memcpy(buf, src, count); 700 *ppos += count; 701 return count; 702 } 703 704 /* 705 * Read from ELF notes data 706 */ 707 ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) 708 { 709 void *src = (void *)(unsigned long)*ppos; 710 711 memcpy(buf, src, count); 712 *ppos += count; 713 return count; 714 } 715