?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Linux 2.6.36-rc5
[linux-2.6/next.git] / fs / proc / vmcore.c
blob91c817ff02c3847a874e1e99f7638b1148869a77
1 /*
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/mm.h>
11 #include <linux/proc_fs.h>
12 #include <linux/user.h>
13 #include <linux/elf.h>
14 #include <linux/elfcore.h>
15 #include <linux/slab.h>
16 #include <linux/highmem.h>
17 #include <linux/bootmem.h>
18 #include <linux/init.h>
19 #include <linux/crash_dump.h>
20 #include <linux/list.h>
21 #include <asm/uaccess.h>
22 #include <asm/io.h>
23
24 /* List representing chunks of contiguous memory areas and their offsets in
25 * vmcore file.
26 */
27 static LIST_HEAD(vmcore_list);
28
29 /* Stores the pointer to the buffer containing kernel elf core headers. */
30 static char *elfcorebuf;
31 static size_t elfcorebuf_sz;
32
33 /* Total size of vmcore file. */
34 static u64 vmcore_size;
35
36 static struct proc_dir_entry *proc_vmcore = NULL;
37
38 /* Reads a page from the oldmem device from given offset. */
39 static ssize_t read_from_oldmem(char *buf, size_t count,
40 u64 *ppos, int userbuf)
41 {
42 unsigned long pfn, offset;
43 size_t nr_bytes;
44 ssize_t read = 0, tmp;
45
46 if (!count)
47 return 0;
48
49 offset = (unsigned long)(*ppos % PAGE_SIZE);
50 pfn = (unsigned long)(*ppos / PAGE_SIZE);
51
52 do {
53 if (count > (PAGE_SIZE - offset))
54 nr_bytes = PAGE_SIZE - offset;
55 else
56 nr_bytes = count;
57
58 tmp = copy_oldmem_page(pfn, buf, nr_bytes, offset, userbuf);
59 if (tmp < 0)
60 return tmp;
61 *ppos += nr_bytes;
62 count -= nr_bytes;
63 buf += nr_bytes;
64 read += nr_bytes;
65 ++pfn;
66 offset = 0;
67 } while (count);
68
69 return read;
70 }
71
72 /* Maps vmcore file offset to respective physical address in memroy. */
73 static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
74 struct vmcore **m_ptr)
75 {
76 struct vmcore *m;
77 u64 paddr;
78
79 list_for_each_entry(m, vc_list, list) {
80 u64 start, end;
81 start = m->offset;
82 end = m->offset + m->size - 1;
83 if (offset >= start && offset <= end) {
84 paddr = m->paddr + offset - start;
85 *m_ptr = m;
86 return paddr;
87 }
88 }
89 *m_ptr = NULL;
90 return 0;
91 }
92
93 /* Read from the ELF header and then the crash dump. On error, negative value is
94 * returned otherwise number of bytes read are returned.
95 */
96 static ssize_t read_vmcore(struct file *file, char __user *buffer,
97 size_t buflen, loff_t *fpos)
98 {
99 ssize_t acc = 0, tmp;
100 size_t tsz;
101 u64 start, nr_bytes;
102 struct vmcore *curr_m = NULL;
103
104 if (buflen == 0 || *fpos >= vmcore_size)
105 return 0;
106
107 /* trim buflen to not go beyond EOF */
108 if (buflen > vmcore_size - *fpos)
109 buflen = vmcore_size - *fpos;
110
111 /* Read ELF core header */
112 if (*fpos < elfcorebuf_sz) {
113 tsz = elfcorebuf_sz - *fpos;
114 if (buflen < tsz)
115 tsz = buflen;
116 if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
117 return -EFAULT;
118 buflen -= tsz;
119 *fpos += tsz;
120 buffer += tsz;
121 acc += tsz;
122
123 /* leave now if filled buffer already */
124 if (buflen == 0)
125 return acc;
126 }
127
128 start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
129 if (!curr_m)
130 return -EINVAL;
131 if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
132 tsz = buflen;
133
134 /* Calculate left bytes in current memory segment. */
135 nr_bytes = (curr_m->size - (start - curr_m->paddr));
136 if (tsz > nr_bytes)
137 tsz = nr_bytes;
138
139 while (buflen) {
140 tmp = read_from_oldmem(buffer, tsz, &start, 1);
141 if (tmp < 0)
142 return tmp;
143 buflen -= tsz;
144 *fpos += tsz;
145 buffer += tsz;
146 acc += tsz;
147 if (start >= (curr_m->paddr + curr_m->size)) {
148 if (curr_m->list.next == &vmcore_list)
149 return acc; /*EOF*/
150 curr_m = list_entry(curr_m->list.next,
151 struct vmcore, list);
152 start = curr_m->paddr;
153 }
154 if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
155 tsz = buflen;
156 /* Calculate left bytes in current memory segment. */
157 nr_bytes = (curr_m->size - (start - curr_m->paddr));
158 if (tsz > nr_bytes)
159 tsz = nr_bytes;
160 }
161 return acc;
162 }
163
164 static const struct file_operations proc_vmcore_operations = {
165 .read = read_vmcore,
166 .llseek = generic_file_llseek,
167 };
168
169 static struct vmcore* __init get_new_element(void)
170 {
171 return kzalloc(sizeof(struct vmcore), GFP_KERNEL);
172 }
173
174 static u64 __init get_vmcore_size_elf64(char *elfptr)
175 {
176 int i;
177 u64 size;
178 Elf64_Ehdr *ehdr_ptr;
179 Elf64_Phdr *phdr_ptr;
180
181 ehdr_ptr = (Elf64_Ehdr *)elfptr;
182 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
183 size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
184 for (i = 0; i < ehdr_ptr->e_phnum; i++) {
185 size += phdr_ptr->p_memsz;
186 phdr_ptr++;
187 }
188 return size;
189 }
190
191 static u64 __init get_vmcore_size_elf32(char *elfptr)
192 {
193 int i;
194 u64 size;
195 Elf32_Ehdr *ehdr_ptr;
196 Elf32_Phdr *phdr_ptr;
197
198 ehdr_ptr = (Elf32_Ehdr *)elfptr;
199 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
200 size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
201 for (i = 0; i < ehdr_ptr->e_phnum; i++) {
202 size += phdr_ptr->p_memsz;
203 phdr_ptr++;
204 }
205 return size;
206 }
207
208 /* Merges all the PT_NOTE headers into one. */
209 static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
210 struct list_head *vc_list)
211 {
212 int i, nr_ptnote=0, rc=0;
213 char *tmp;
214 Elf64_Ehdr *ehdr_ptr;
215 Elf64_Phdr phdr, *phdr_ptr;
216 Elf64_Nhdr *nhdr_ptr;
217 u64 phdr_sz = 0, note_off;
218
219 ehdr_ptr = (Elf64_Ehdr *)elfptr;
220 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
221 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
222 int j;
223 void *notes_section;
224 struct vmcore *new;
225 u64 offset, max_sz, sz, real_sz = 0;
226 if (phdr_ptr->p_type != PT_NOTE)
227 continue;
228 nr_ptnote++;
229 max_sz = phdr_ptr->p_memsz;
230 offset = phdr_ptr->p_offset;
231 notes_section = kmalloc(max_sz, GFP_KERNEL);
232 if (!notes_section)
233 return -ENOMEM;
234 rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
235 if (rc < 0) {
236 kfree(notes_section);
237 return rc;
238 }
239 nhdr_ptr = notes_section;
240 for (j = 0; j < max_sz; j += sz) {
241 if (nhdr_ptr->n_namesz == 0)
242 break;
243 sz = sizeof(Elf64_Nhdr) +
244 ((nhdr_ptr->n_namesz + 3) & ~3) +
245 ((nhdr_ptr->n_descsz + 3) & ~3);
246 real_sz += sz;
247 nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
248 }
249
250 /* Add this contiguous chunk of notes section to vmcore list.*/
251 new = get_new_element();
252 if (!new) {
253 kfree(notes_section);
254 return -ENOMEM;
255 }
256 new->paddr = phdr_ptr->p_offset;
257 new->size = real_sz;
258 list_add_tail(&new->list, vc_list);
259 phdr_sz += real_sz;
260 kfree(notes_section);
261 }
262
263 /* Prepare merged PT_NOTE program header. */
264 phdr.p_type = PT_NOTE;
265 phdr.p_flags = 0;
266 note_off = sizeof(Elf64_Ehdr) +
267 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
268 phdr.p_offset = note_off;
269 phdr.p_vaddr = phdr.p_paddr = 0;
270 phdr.p_filesz = phdr.p_memsz = phdr_sz;
271 phdr.p_align = 0;
272
273 /* Add merged PT_NOTE program header*/
274 tmp = elfptr + sizeof(Elf64_Ehdr);
275 memcpy(tmp, &phdr, sizeof(phdr));
276 tmp += sizeof(phdr);
277
278 /* Remove unwanted PT_NOTE program headers. */
279 i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
280 *elfsz = *elfsz - i;
281 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
282
283 /* Modify e_phnum to reflect merged headers. */
284 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
285
286 return 0;
287 }
288
289 /* Merges all the PT_NOTE headers into one. */
290 static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
291 struct list_head *vc_list)
292 {
293 int i, nr_ptnote=0, rc=0;
294 char *tmp;
295 Elf32_Ehdr *ehdr_ptr;
296 Elf32_Phdr phdr, *phdr_ptr;
297 Elf32_Nhdr *nhdr_ptr;
298 u64 phdr_sz = 0, note_off;
299
300 ehdr_ptr = (Elf32_Ehdr *)elfptr;
301 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
302 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
303 int j;
304 void *notes_section;
305 struct vmcore *new;
306 u64 offset, max_sz, sz, real_sz = 0;
307 if (phdr_ptr->p_type != PT_NOTE)
308 continue;
309 nr_ptnote++;
310 max_sz = phdr_ptr->p_memsz;
311 offset = phdr_ptr->p_offset;
312 notes_section = kmalloc(max_sz, GFP_KERNEL);
313 if (!notes_section)
314 return -ENOMEM;
315 rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
316 if (rc < 0) {
317 kfree(notes_section);
318 return rc;
319 }
320 nhdr_ptr = notes_section;
321 for (j = 0; j < max_sz; j += sz) {
322 if (nhdr_ptr->n_namesz == 0)
323 break;
324 sz = sizeof(Elf32_Nhdr) +
325 ((nhdr_ptr->n_namesz + 3) & ~3) +
326 ((nhdr_ptr->n_descsz + 3) & ~3);
327 real_sz += sz;
328 nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
329 }
330
331 /* Add this contiguous chunk of notes section to vmcore list.*/
332 new = get_new_element();
333 if (!new) {
334 kfree(notes_section);
335 return -ENOMEM;
336 }
337 new->paddr = phdr_ptr->p_offset;
338 new->size = real_sz;
339 list_add_tail(&new->list, vc_list);
340 phdr_sz += real_sz;
341 kfree(notes_section);
342 }
343
344 /* Prepare merged PT_NOTE program header. */
345 phdr.p_type = PT_NOTE;
346 phdr.p_flags = 0;
347 note_off = sizeof(Elf32_Ehdr) +
348 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
349 phdr.p_offset = note_off;
350 phdr.p_vaddr = phdr.p_paddr = 0;
351 phdr.p_filesz = phdr.p_memsz = phdr_sz;
352 phdr.p_align = 0;
353
354 /* Add merged PT_NOTE program header*/
355 tmp = elfptr + sizeof(Elf32_Ehdr);
356 memcpy(tmp, &phdr, sizeof(phdr));
357 tmp += sizeof(phdr);
358
359 /* Remove unwanted PT_NOTE program headers. */
360 i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
361 *elfsz = *elfsz - i;
362 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
363
364 /* Modify e_phnum to reflect merged headers. */
365 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
366
367 return 0;
368 }
369
370 /* Add memory chunks represented by program headers to vmcore list. Also update
371 * the new offset fields of exported program headers. */
372 static int __init process_ptload_program_headers_elf64(char *elfptr,
373 size_t elfsz,
374 struct list_head *vc_list)
375 {
376 int i;
377 Elf64_Ehdr *ehdr_ptr;
378 Elf64_Phdr *phdr_ptr;
379 loff_t vmcore_off;
380 struct vmcore *new;
381
382 ehdr_ptr = (Elf64_Ehdr *)elfptr;
383 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
384
385 /* First program header is PT_NOTE header. */
386 vmcore_off = sizeof(Elf64_Ehdr) +
387 (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
388 phdr_ptr->p_memsz; /* Note sections */
389
390 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
391 if (phdr_ptr->p_type != PT_LOAD)
392 continue;
393
394 /* Add this contiguous chunk of memory to vmcore list.*/
395 new = get_new_element();
396 if (!new)
397 return -ENOMEM;
398 new->paddr = phdr_ptr->p_offset;
399 new->size = phdr_ptr->p_memsz;
400 list_add_tail(&new->list, vc_list);
401
402 /* Update the program header offset. */
403 phdr_ptr->p_offset = vmcore_off;
404 vmcore_off = vmcore_off + phdr_ptr->p_memsz;
405 }
406 return 0;
407 }
408
409 static int __init process_ptload_program_headers_elf32(char *elfptr,
410 size_t elfsz,
411 struct list_head *vc_list)
412 {
413 int i;
414 Elf32_Ehdr *ehdr_ptr;
415 Elf32_Phdr *phdr_ptr;
416 loff_t vmcore_off;
417 struct vmcore *new;
418
419 ehdr_ptr = (Elf32_Ehdr *)elfptr;
420 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
421
422 /* First program header is PT_NOTE header. */
423 vmcore_off = sizeof(Elf32_Ehdr) +
424 (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
425 phdr_ptr->p_memsz; /* Note sections */
426
427 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
428 if (phdr_ptr->p_type != PT_LOAD)
429 continue;
430
431 /* Add this contiguous chunk of memory to vmcore list.*/
432 new = get_new_element();
433 if (!new)
434 return -ENOMEM;
435 new->paddr = phdr_ptr->p_offset;
436 new->size = phdr_ptr->p_memsz;
437 list_add_tail(&new->list, vc_list);
438
439 /* Update the program header offset */
440 phdr_ptr->p_offset = vmcore_off;
441 vmcore_off = vmcore_off + phdr_ptr->p_memsz;
442 }
443 return 0;
444 }
445
446 /* Sets offset fields of vmcore elements. */
447 static void __init set_vmcore_list_offsets_elf64(char *elfptr,
448 struct list_head *vc_list)
449 {
450 loff_t vmcore_off;
451 Elf64_Ehdr *ehdr_ptr;
452 struct vmcore *m;
453
454 ehdr_ptr = (Elf64_Ehdr *)elfptr;
455
456 /* Skip Elf header and program headers. */
457 vmcore_off = sizeof(Elf64_Ehdr) +
458 (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
459
460 list_for_each_entry(m, vc_list, list) {
461 m->offset = vmcore_off;
462 vmcore_off += m->size;
463 }
464 }
465
466 /* Sets offset fields of vmcore elements. */
467 static void __init set_vmcore_list_offsets_elf32(char *elfptr,
468 struct list_head *vc_list)
469 {
470 loff_t vmcore_off;
471 Elf32_Ehdr *ehdr_ptr;
472 struct vmcore *m;
473
474 ehdr_ptr = (Elf32_Ehdr *)elfptr;
475
476 /* Skip Elf header and program headers. */
477 vmcore_off = sizeof(Elf32_Ehdr) +
478 (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
479
480 list_for_each_entry(m, vc_list, list) {
481 m->offset = vmcore_off;
482 vmcore_off += m->size;
483 }
484 }
485
486 static int __init parse_crash_elf64_headers(void)
487 {
488 int rc=0;
489 Elf64_Ehdr ehdr;
490 u64 addr;
491
492 addr = elfcorehdr_addr;
493
494 /* Read Elf header */
495 rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0);
496 if (rc < 0)
497 return rc;
498
499 /* Do some basic Verification. */
500 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
501 (ehdr.e_type != ET_CORE) ||
502 !vmcore_elf_check_arch(&ehdr) ||
503 ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
504 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
505 ehdr.e_version != EV_CURRENT ||
506 ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
507 ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
508 ehdr.e_phnum == 0) {
509 printk(KERN_WARNING "Warning: Core image elf header is not"
510 "sane\n");
511 return -EINVAL;
512 }
513
514 /* Read in all elf headers. */
515 elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
516 elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
517 if (!elfcorebuf)
518 return -ENOMEM;
519 addr = elfcorehdr_addr;
520 rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
521 if (rc < 0) {
522 kfree(elfcorebuf);
523 return rc;
524 }
525
526 /* Merge all PT_NOTE headers into one. */
527 rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
528 if (rc) {
529 kfree(elfcorebuf);
530 return rc;
531 }
532 rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
533 &vmcore_list);
534 if (rc) {
535 kfree(elfcorebuf);
536 return rc;
537 }
538 set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
539 return 0;
540 }
541
542 static int __init parse_crash_elf32_headers(void)
543 {
544 int rc=0;
545 Elf32_Ehdr ehdr;
546 u64 addr;
547
548 addr = elfcorehdr_addr;
549
550 /* Read Elf header */
551 rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0);
552 if (rc < 0)
553 return rc;
554
555 /* Do some basic Verification. */
556 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
557 (ehdr.e_type != ET_CORE) ||
558 !elf_check_arch(&ehdr) ||
559 ehdr.e_ident[EI_CLASS] != ELFCLASS32||
560 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
561 ehdr.e_version != EV_CURRENT ||
562 ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
563 ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
564 ehdr.e_phnum == 0) {
565 printk(KERN_WARNING "Warning: Core image elf header is not"
566 "sane\n");
567 return -EINVAL;
568 }
569
570 /* Read in all elf headers. */
571 elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
572 elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
573 if (!elfcorebuf)
574 return -ENOMEM;
575 addr = elfcorehdr_addr;
576 rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
577 if (rc < 0) {
578 kfree(elfcorebuf);
579 return rc;
580 }
581
582 /* Merge all PT_NOTE headers into one. */
583 rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
584 if (rc) {
585 kfree(elfcorebuf);
586 return rc;
587 }
588 rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
589 &vmcore_list);
590 if (rc) {
591 kfree(elfcorebuf);
592 return rc;
593 }
594 set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
595 return 0;
596 }
597
598 static int __init parse_crash_elf_headers(void)
599 {
600 unsigned char e_ident[EI_NIDENT];
601 u64 addr;
602 int rc=0;
603
604 addr = elfcorehdr_addr;
605 rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0);
606 if (rc < 0)
607 return rc;
608 if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
609 printk(KERN_WARNING "Warning: Core image elf header"
610 " not found\n");
611 return -EINVAL;
612 }
613
614 if (e_ident[EI_CLASS] == ELFCLASS64) {
615 rc = parse_crash_elf64_headers();
616 if (rc)
617 return rc;
618
619 /* Determine vmcore size. */
620 vmcore_size = get_vmcore_size_elf64(elfcorebuf);
621 } else if (e_ident[EI_CLASS] == ELFCLASS32) {
622 rc = parse_crash_elf32_headers();
623 if (rc)
624 return rc;
625
626 /* Determine vmcore size. */
627 vmcore_size = get_vmcore_size_elf32(elfcorebuf);
628 } else {
629 printk(KERN_WARNING "Warning: Core image elf header is not"
630 " sane\n");
631 return -EINVAL;
632 }
633 return 0;
634 }
635
636 /* Init function for vmcore module. */
637 static int __init vmcore_init(void)
638 {
639 int rc = 0;
640
641 /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/
642 if (!(is_vmcore_usable()))
643 return rc;
644 rc = parse_crash_elf_headers();
645 if (rc) {
646 printk(KERN_WARNING "Kdump: vmcore not initialized\n");
647 return rc;
648 }
649
650 proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations);
651 if (proc_vmcore)
652 proc_vmcore->size = vmcore_size;
653 return 0;
654 }
655 module_init(vmcore_init)
linux-next