blob: 4063fb32f78c210dd6c41690ff107966e68ed821 [file] [log] [blame]
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001/*
2 * fs/proc/vmcore.c Interface for accessing the crash
3 * dump from the system's previous life.
4 * Heavily borrowed from fs/proc/kcore.c
5 * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
6 * Copyright (C) IBM Corporation, 2004. All rights reserved
7 *
8 */
9
10#include <linux/config.h>
11#include <linux/mm.h>
12#include <linux/proc_fs.h>
13#include <linux/user.h>
14#include <linux/a.out.h>
15#include <linux/elf.h>
16#include <linux/elfcore.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070017#include <linux/highmem.h>
18#include <linux/bootmem.h>
19#include <linux/init.h>
20#include <linux/crash_dump.h>
21#include <linux/list.h>
22#include <asm/uaccess.h>
23#include <asm/io.h>
24
25/* List representing chunks of contiguous memory areas and their offsets in
26 * vmcore file.
27 */
28static LIST_HEAD(vmcore_list);
29
30/* Stores the pointer to the buffer containing kernel elf core headers. */
31static char *elfcorebuf;
32static size_t elfcorebuf_sz;
33
34/* Total size of vmcore file. */
35static u64 vmcore_size;
36
Vivek Goyal4ae362b2006-01-09 20:51:50 -080037/* Stores the physical address of elf header of crash image. */
38unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
39
Vivek Goyal666bfdd2005-06-25 14:58:21 -070040struct proc_dir_entry *proc_vmcore = NULL;
41
42/* Reads a page from the oldmem device from given offset. */
43static ssize_t read_from_oldmem(char *buf, size_t count,
Vivek Goyal9e9e3942006-01-11 12:17:37 -080044 u64 *ppos, int userbuf)
Vivek Goyal666bfdd2005-06-25 14:58:21 -070045{
46 unsigned long pfn, offset;
47 size_t nr_bytes;
48 ssize_t read = 0, tmp;
49
50 if (!count)
51 return 0;
52
53 offset = (unsigned long)(*ppos % PAGE_SIZE);
54 pfn = (unsigned long)(*ppos / PAGE_SIZE);
55 if (pfn > saved_max_pfn)
56 return -EINVAL;
57
58 do {
59 if (count > (PAGE_SIZE - offset))
60 nr_bytes = PAGE_SIZE - offset;
61 else
62 nr_bytes = count;
63
64 tmp = copy_oldmem_page(pfn, buf, nr_bytes, offset, userbuf);
65 if (tmp < 0)
66 return tmp;
67 *ppos += nr_bytes;
68 count -= nr_bytes;
69 buf += nr_bytes;
70 read += nr_bytes;
71 ++pfn;
72 offset = 0;
73 } while (count);
74
75 return read;
76}
77
78/* Maps vmcore file offset to respective physical address in memroy. */
79static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
80 struct vmcore **m_ptr)
81{
82 struct vmcore *m;
83 u64 paddr;
84
85 list_for_each_entry(m, vc_list, list) {
86 u64 start, end;
87 start = m->offset;
88 end = m->offset + m->size - 1;
89 if (offset >= start && offset <= end) {
90 paddr = m->paddr + offset - start;
91 *m_ptr = m;
92 return paddr;
93 }
94 }
95 *m_ptr = NULL;
96 return 0;
97}
98
99/* Read from the ELF header and then the crash dump. On error, negative value is
100 * returned otherwise number of bytes read are returned.
101 */
102static ssize_t read_vmcore(struct file *file, char __user *buffer,
103 size_t buflen, loff_t *fpos)
104{
105 ssize_t acc = 0, tmp;
106 size_t tsz, nr_bytes;
107 u64 start;
108 struct vmcore *curr_m = NULL;
109
110 if (buflen == 0 || *fpos >= vmcore_size)
111 return 0;
112
113 /* trim buflen to not go beyond EOF */
114 if (buflen > vmcore_size - *fpos)
115 buflen = vmcore_size - *fpos;
116
117 /* Read ELF core header */
118 if (*fpos < elfcorebuf_sz) {
119 tsz = elfcorebuf_sz - *fpos;
120 if (buflen < tsz)
121 tsz = buflen;
122 if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
123 return -EFAULT;
124 buflen -= tsz;
125 *fpos += tsz;
126 buffer += tsz;
127 acc += tsz;
128
129 /* leave now if filled buffer already */
130 if (buflen == 0)
131 return acc;
132 }
133
134 start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
135 if (!curr_m)
136 return -EINVAL;
137 if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
138 tsz = buflen;
139
140 /* Calculate left bytes in current memory segment. */
141 nr_bytes = (curr_m->size - (start - curr_m->paddr));
142 if (tsz > nr_bytes)
143 tsz = nr_bytes;
144
145 while (buflen) {
146 tmp = read_from_oldmem(buffer, tsz, &start, 1);
147 if (tmp < 0)
148 return tmp;
149 buflen -= tsz;
150 *fpos += tsz;
151 buffer += tsz;
152 acc += tsz;
153 if (start >= (curr_m->paddr + curr_m->size)) {
154 if (curr_m->list.next == &vmcore_list)
155 return acc; /*EOF*/
156 curr_m = list_entry(curr_m->list.next,
157 struct vmcore, list);
158 start = curr_m->paddr;
159 }
160 if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
161 tsz = buflen;
162 /* Calculate left bytes in current memory segment. */
163 nr_bytes = (curr_m->size - (start - curr_m->paddr));
164 if (tsz > nr_bytes)
165 tsz = nr_bytes;
166 }
167 return acc;
168}
169
170static int open_vmcore(struct inode *inode, struct file *filp)
171{
172 return 0;
173}
174
175struct file_operations proc_vmcore_operations = {
176 .read = read_vmcore,
177 .open = open_vmcore,
178};
179
180static struct vmcore* __init get_new_element(void)
181{
182 struct vmcore *p;
183
184 p = kmalloc(sizeof(*p), GFP_KERNEL);
185 if (p)
186 memset(p, 0, sizeof(*p));
187 return p;
188}
189
190static u64 __init get_vmcore_size_elf64(char *elfptr)
191{
192 int i;
193 u64 size;
194 Elf64_Ehdr *ehdr_ptr;
195 Elf64_Phdr *phdr_ptr;
196
197 ehdr_ptr = (Elf64_Ehdr *)elfptr;
198 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
199 size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
200 for (i = 0; i < ehdr_ptr->e_phnum; i++) {
201 size += phdr_ptr->p_memsz;
202 phdr_ptr++;
203 }
204 return size;
205}
206
Vivek Goyal72658e92005-06-25 14:58:22 -0700207static u64 __init get_vmcore_size_elf32(char *elfptr)
208{
209 int i;
210 u64 size;
211 Elf32_Ehdr *ehdr_ptr;
212 Elf32_Phdr *phdr_ptr;
213
214 ehdr_ptr = (Elf32_Ehdr *)elfptr;
215 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
216 size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
217 for (i = 0; i < ehdr_ptr->e_phnum; i++) {
218 size += phdr_ptr->p_memsz;
219 phdr_ptr++;
220 }
221 return size;
222}
223
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700224/* Merges all the PT_NOTE headers into one. */
225static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
226 struct list_head *vc_list)
227{
228 int i, nr_ptnote=0, rc=0;
229 char *tmp;
230 Elf64_Ehdr *ehdr_ptr;
231 Elf64_Phdr phdr, *phdr_ptr;
232 Elf64_Nhdr *nhdr_ptr;
233 u64 phdr_sz = 0, note_off;
234
235 ehdr_ptr = (Elf64_Ehdr *)elfptr;
236 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
237 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
238 int j;
239 void *notes_section;
240 struct vmcore *new;
241 u64 offset, max_sz, sz, real_sz = 0;
242 if (phdr_ptr->p_type != PT_NOTE)
243 continue;
244 nr_ptnote++;
245 max_sz = phdr_ptr->p_memsz;
246 offset = phdr_ptr->p_offset;
247 notes_section = kmalloc(max_sz, GFP_KERNEL);
248 if (!notes_section)
249 return -ENOMEM;
250 rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
251 if (rc < 0) {
252 kfree(notes_section);
253 return rc;
254 }
255 nhdr_ptr = notes_section;
256 for (j = 0; j < max_sz; j += sz) {
257 if (nhdr_ptr->n_namesz == 0)
258 break;
259 sz = sizeof(Elf64_Nhdr) +
260 ((nhdr_ptr->n_namesz + 3) & ~3) +
261 ((nhdr_ptr->n_descsz + 3) & ~3);
262 real_sz += sz;
263 nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
264 }
265
266 /* Add this contiguous chunk of notes section to vmcore list.*/
267 new = get_new_element();
268 if (!new) {
269 kfree(notes_section);
270 return -ENOMEM;
271 }
272 new->paddr = phdr_ptr->p_offset;
273 new->size = real_sz;
274 list_add_tail(&new->list, vc_list);
275 phdr_sz += real_sz;
276 kfree(notes_section);
277 }
278
279 /* Prepare merged PT_NOTE program header. */
280 phdr.p_type = PT_NOTE;
281 phdr.p_flags = 0;
282 note_off = sizeof(Elf64_Ehdr) +
283 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
284 phdr.p_offset = note_off;
285 phdr.p_vaddr = phdr.p_paddr = 0;
286 phdr.p_filesz = phdr.p_memsz = phdr_sz;
287 phdr.p_align = 0;
288
289 /* Add merged PT_NOTE program header*/
290 tmp = elfptr + sizeof(Elf64_Ehdr);
291 memcpy(tmp, &phdr, sizeof(phdr));
292 tmp += sizeof(phdr);
293
294 /* Remove unwanted PT_NOTE program headers. */
295 i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
296 *elfsz = *elfsz - i;
297 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
298
299 /* Modify e_phnum to reflect merged headers. */
300 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
301
302 return 0;
303}
304
Vivek Goyal72658e92005-06-25 14:58:22 -0700305/* Merges all the PT_NOTE headers into one. */
306static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
307 struct list_head *vc_list)
308{
309 int i, nr_ptnote=0, rc=0;
310 char *tmp;
311 Elf32_Ehdr *ehdr_ptr;
312 Elf32_Phdr phdr, *phdr_ptr;
313 Elf32_Nhdr *nhdr_ptr;
314 u64 phdr_sz = 0, note_off;
315
316 ehdr_ptr = (Elf32_Ehdr *)elfptr;
317 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
318 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
319 int j;
320 void *notes_section;
321 struct vmcore *new;
322 u64 offset, max_sz, sz, real_sz = 0;
323 if (phdr_ptr->p_type != PT_NOTE)
324 continue;
325 nr_ptnote++;
326 max_sz = phdr_ptr->p_memsz;
327 offset = phdr_ptr->p_offset;
328 notes_section = kmalloc(max_sz, GFP_KERNEL);
329 if (!notes_section)
330 return -ENOMEM;
331 rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
332 if (rc < 0) {
333 kfree(notes_section);
334 return rc;
335 }
336 nhdr_ptr = notes_section;
337 for (j = 0; j < max_sz; j += sz) {
338 if (nhdr_ptr->n_namesz == 0)
339 break;
340 sz = sizeof(Elf32_Nhdr) +
341 ((nhdr_ptr->n_namesz + 3) & ~3) +
342 ((nhdr_ptr->n_descsz + 3) & ~3);
343 real_sz += sz;
344 nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
345 }
346
347 /* Add this contiguous chunk of notes section to vmcore list.*/
348 new = get_new_element();
349 if (!new) {
350 kfree(notes_section);
351 return -ENOMEM;
352 }
353 new->paddr = phdr_ptr->p_offset;
354 new->size = real_sz;
355 list_add_tail(&new->list, vc_list);
356 phdr_sz += real_sz;
357 kfree(notes_section);
358 }
359
360 /* Prepare merged PT_NOTE program header. */
361 phdr.p_type = PT_NOTE;
362 phdr.p_flags = 0;
363 note_off = sizeof(Elf32_Ehdr) +
364 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
365 phdr.p_offset = note_off;
366 phdr.p_vaddr = phdr.p_paddr = 0;
367 phdr.p_filesz = phdr.p_memsz = phdr_sz;
368 phdr.p_align = 0;
369
370 /* Add merged PT_NOTE program header*/
371 tmp = elfptr + sizeof(Elf32_Ehdr);
372 memcpy(tmp, &phdr, sizeof(phdr));
373 tmp += sizeof(phdr);
374
375 /* Remove unwanted PT_NOTE program headers. */
376 i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
377 *elfsz = *elfsz - i;
378 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
379
380 /* Modify e_phnum to reflect merged headers. */
381 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
382
383 return 0;
384}
385
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700386/* Add memory chunks represented by program headers to vmcore list. Also update
387 * the new offset fields of exported program headers. */
388static int __init process_ptload_program_headers_elf64(char *elfptr,
389 size_t elfsz,
390 struct list_head *vc_list)
391{
392 int i;
393 Elf64_Ehdr *ehdr_ptr;
394 Elf64_Phdr *phdr_ptr;
395 loff_t vmcore_off;
396 struct vmcore *new;
397
398 ehdr_ptr = (Elf64_Ehdr *)elfptr;
399 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
400
401 /* First program header is PT_NOTE header. */
402 vmcore_off = sizeof(Elf64_Ehdr) +
403 (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
404 phdr_ptr->p_memsz; /* Note sections */
405
406 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
407 if (phdr_ptr->p_type != PT_LOAD)
408 continue;
409
410 /* Add this contiguous chunk of memory to vmcore list.*/
411 new = get_new_element();
412 if (!new)
413 return -ENOMEM;
414 new->paddr = phdr_ptr->p_offset;
415 new->size = phdr_ptr->p_memsz;
416 list_add_tail(&new->list, vc_list);
417
418 /* Update the program header offset. */
419 phdr_ptr->p_offset = vmcore_off;
420 vmcore_off = vmcore_off + phdr_ptr->p_memsz;
421 }
422 return 0;
423}
424
Vivek Goyal72658e92005-06-25 14:58:22 -0700425static int __init process_ptload_program_headers_elf32(char *elfptr,
426 size_t elfsz,
427 struct list_head *vc_list)
428{
429 int i;
430 Elf32_Ehdr *ehdr_ptr;
431 Elf32_Phdr *phdr_ptr;
432 loff_t vmcore_off;
433 struct vmcore *new;
434
435 ehdr_ptr = (Elf32_Ehdr *)elfptr;
436 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
437
438 /* First program header is PT_NOTE header. */
439 vmcore_off = sizeof(Elf32_Ehdr) +
440 (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
441 phdr_ptr->p_memsz; /* Note sections */
442
443 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
444 if (phdr_ptr->p_type != PT_LOAD)
445 continue;
446
447 /* Add this contiguous chunk of memory to vmcore list.*/
448 new = get_new_element();
449 if (!new)
450 return -ENOMEM;
451 new->paddr = phdr_ptr->p_offset;
452 new->size = phdr_ptr->p_memsz;
453 list_add_tail(&new->list, vc_list);
454
455 /* Update the program header offset */
456 phdr_ptr->p_offset = vmcore_off;
457 vmcore_off = vmcore_off + phdr_ptr->p_memsz;
458 }
459 return 0;
460}
461
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700462/* Sets offset fields of vmcore elements. */
463static void __init set_vmcore_list_offsets_elf64(char *elfptr,
464 struct list_head *vc_list)
465{
466 loff_t vmcore_off;
467 Elf64_Ehdr *ehdr_ptr;
468 struct vmcore *m;
469
470 ehdr_ptr = (Elf64_Ehdr *)elfptr;
471
472 /* Skip Elf header and program headers. */
473 vmcore_off = sizeof(Elf64_Ehdr) +
474 (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
475
476 list_for_each_entry(m, vc_list, list) {
477 m->offset = vmcore_off;
478 vmcore_off += m->size;
479 }
480}
481
Vivek Goyal72658e92005-06-25 14:58:22 -0700482/* Sets offset fields of vmcore elements. */
483static void __init set_vmcore_list_offsets_elf32(char *elfptr,
484 struct list_head *vc_list)
485{
486 loff_t vmcore_off;
487 Elf32_Ehdr *ehdr_ptr;
488 struct vmcore *m;
489
490 ehdr_ptr = (Elf32_Ehdr *)elfptr;
491
492 /* Skip Elf header and program headers. */
493 vmcore_off = sizeof(Elf32_Ehdr) +
494 (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
495
496 list_for_each_entry(m, vc_list, list) {
497 m->offset = vmcore_off;
498 vmcore_off += m->size;
499 }
500}
501
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700502static int __init parse_crash_elf64_headers(void)
503{
504 int rc=0;
505 Elf64_Ehdr ehdr;
506 u64 addr;
507
508 addr = elfcorehdr_addr;
509
510 /* Read Elf header */
511 rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0);
512 if (rc < 0)
513 return rc;
514
515 /* Do some basic Verification. */
516 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
517 (ehdr.e_type != ET_CORE) ||
518 !elf_check_arch(&ehdr) ||
519 ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
520 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
521 ehdr.e_version != EV_CURRENT ||
522 ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
523 ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
524 ehdr.e_phnum == 0) {
525 printk(KERN_WARNING "Warning: Core image elf header is not"
526 "sane\n");
527 return -EINVAL;
528 }
529
530 /* Read in all elf headers. */
531 elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
532 elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
533 if (!elfcorebuf)
534 return -ENOMEM;
535 addr = elfcorehdr_addr;
536 rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
537 if (rc < 0) {
538 kfree(elfcorebuf);
539 return rc;
540 }
541
542 /* Merge all PT_NOTE headers into one. */
543 rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
544 if (rc) {
545 kfree(elfcorebuf);
546 return rc;
547 }
548 rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
549 &vmcore_list);
550 if (rc) {
551 kfree(elfcorebuf);
552 return rc;
553 }
554 set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
555 return 0;
556}
557
Vivek Goyal72658e92005-06-25 14:58:22 -0700558static int __init parse_crash_elf32_headers(void)
559{
560 int rc=0;
561 Elf32_Ehdr ehdr;
562 u64 addr;
563
564 addr = elfcorehdr_addr;
565
566 /* Read Elf header */
567 rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0);
568 if (rc < 0)
569 return rc;
570
571 /* Do some basic Verification. */
572 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
573 (ehdr.e_type != ET_CORE) ||
574 !elf_check_arch(&ehdr) ||
575 ehdr.e_ident[EI_CLASS] != ELFCLASS32||
576 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
577 ehdr.e_version != EV_CURRENT ||
578 ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
579 ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
580 ehdr.e_phnum == 0) {
581 printk(KERN_WARNING "Warning: Core image elf header is not"
582 "sane\n");
583 return -EINVAL;
584 }
585
586 /* Read in all elf headers. */
587 elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
588 elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
589 if (!elfcorebuf)
590 return -ENOMEM;
591 addr = elfcorehdr_addr;
592 rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
593 if (rc < 0) {
594 kfree(elfcorebuf);
595 return rc;
596 }
597
598 /* Merge all PT_NOTE headers into one. */
599 rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
600 if (rc) {
601 kfree(elfcorebuf);
602 return rc;
603 }
604 rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
605 &vmcore_list);
606 if (rc) {
607 kfree(elfcorebuf);
608 return rc;
609 }
610 set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
611 return 0;
612}
613
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700614static int __init parse_crash_elf_headers(void)
615{
616 unsigned char e_ident[EI_NIDENT];
617 u64 addr;
618 int rc=0;
619
620 addr = elfcorehdr_addr;
621 rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0);
622 if (rc < 0)
623 return rc;
624 if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
625 printk(KERN_WARNING "Warning: Core image elf header"
626 " not found\n");
627 return -EINVAL;
628 }
629
630 if (e_ident[EI_CLASS] == ELFCLASS64) {
631 rc = parse_crash_elf64_headers();
632 if (rc)
633 return rc;
634
635 /* Determine vmcore size. */
636 vmcore_size = get_vmcore_size_elf64(elfcorebuf);
Vivek Goyal72658e92005-06-25 14:58:22 -0700637 } else if (e_ident[EI_CLASS] == ELFCLASS32) {
638 rc = parse_crash_elf32_headers();
639 if (rc)
640 return rc;
641
642 /* Determine vmcore size. */
643 vmcore_size = get_vmcore_size_elf32(elfcorebuf);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700644 } else {
645 printk(KERN_WARNING "Warning: Core image elf header is not"
646 " sane\n");
647 return -EINVAL;
648 }
649 return 0;
650}
651
652/* Init function for vmcore module. */
653static int __init vmcore_init(void)
654{
655 int rc = 0;
656
657 /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/
658 if (!(elfcorehdr_addr < ELFCORE_ADDR_MAX))
659 return rc;
660 rc = parse_crash_elf_headers();
661 if (rc) {
662 printk(KERN_WARNING "Kdump: vmcore not initialized\n");
663 return rc;
664 }
665
666 /* Initialize /proc/vmcore size if proc is already up. */
667 if (proc_vmcore)
668 proc_vmcore->size = vmcore_size;
669 return 0;
670}
671module_init(vmcore_init)