Commit | Line | Data |
---|---|---|
666bfddb VG |
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 | ||
666bfddb VG |
10 | #include <linux/mm.h> |
11 | #include <linux/proc_fs.h> | |
12 | #include <linux/user.h> | |
666bfddb VG |
13 | #include <linux/elf.h> |
14 | #include <linux/elfcore.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
666bfddb VG |
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 | ||
5aa140c2 | 36 | static struct proc_dir_entry *proc_vmcore = NULL; |
666bfddb | 37 | |
997c136f OH |
38 | /* |
39 | * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error | |
40 | * The called function has to take care of module refcounting. | |
41 | */ | |
42 | static int (*oldmem_pfn_is_ram)(unsigned long pfn); | |
43 | ||
44 | int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn)) | |
45 | { | |
46 | if (oldmem_pfn_is_ram) | |
47 | return -EBUSY; | |
48 | oldmem_pfn_is_ram = fn; | |
49 | return 0; | |
50 | } | |
51 | EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram); | |
52 | ||
53 | void unregister_oldmem_pfn_is_ram(void) | |
54 | { | |
55 | oldmem_pfn_is_ram = NULL; | |
56 | wmb(); | |
57 | } | |
58 | EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram); | |
59 | ||
60 | static int pfn_is_ram(unsigned long pfn) | |
61 | { | |
62 | int (*fn)(unsigned long pfn); | |
63 | /* pfn is ram unless fn() checks pagetype */ | |
64 | int ret = 1; | |
65 | ||
66 | /* | |
67 | * Ask hypervisor if the pfn is really ram. | |
68 | * A ballooned page contains no data and reading from such a page | |
69 | * will cause high load in the hypervisor. | |
70 | */ | |
71 | fn = oldmem_pfn_is_ram; | |
72 | if (fn) | |
73 | ret = fn(pfn); | |
74 | ||
75 | return ret; | |
76 | } | |
77 | ||
666bfddb VG |
78 | /* Reads a page from the oldmem device from given offset. */ |
79 | static ssize_t read_from_oldmem(char *buf, size_t count, | |
9e9e3941 | 80 | u64 *ppos, int userbuf) |
666bfddb VG |
81 | { |
82 | unsigned long pfn, offset; | |
83 | size_t nr_bytes; | |
84 | ssize_t read = 0, tmp; | |
85 | ||
86 | if (!count) | |
87 | return 0; | |
88 | ||
89 | offset = (unsigned long)(*ppos % PAGE_SIZE); | |
90 | pfn = (unsigned long)(*ppos / PAGE_SIZE); | |
666bfddb VG |
91 | |
92 | do { | |
93 | if (count > (PAGE_SIZE - offset)) | |
94 | nr_bytes = PAGE_SIZE - offset; | |
95 | else | |
96 | nr_bytes = count; | |
97 | ||
997c136f OH |
98 | /* If pfn is not ram, return zeros for sparse dump files */ |
99 | if (pfn_is_ram(pfn) == 0) | |
100 | memset(buf, 0, nr_bytes); | |
101 | else { | |
102 | tmp = copy_oldmem_page(pfn, buf, nr_bytes, | |
103 | offset, userbuf); | |
104 | if (tmp < 0) | |
105 | return tmp; | |
106 | } | |
666bfddb VG |
107 | *ppos += nr_bytes; |
108 | count -= nr_bytes; | |
109 | buf += nr_bytes; | |
110 | read += nr_bytes; | |
111 | ++pfn; | |
112 | offset = 0; | |
113 | } while (count); | |
114 | ||
115 | return read; | |
116 | } | |
117 | ||
118 | /* Maps vmcore file offset to respective physical address in memroy. */ | |
119 | static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list, | |
120 | struct vmcore **m_ptr) | |
121 | { | |
122 | struct vmcore *m; | |
123 | u64 paddr; | |
124 | ||
125 | list_for_each_entry(m, vc_list, list) { | |
126 | u64 start, end; | |
127 | start = m->offset; | |
128 | end = m->offset + m->size - 1; | |
129 | if (offset >= start && offset <= end) { | |
130 | paddr = m->paddr + offset - start; | |
131 | *m_ptr = m; | |
132 | return paddr; | |
133 | } | |
134 | } | |
135 | *m_ptr = NULL; | |
136 | return 0; | |
137 | } | |
138 | ||
139 | /* Read from the ELF header and then the crash dump. On error, negative value is | |
140 | * returned otherwise number of bytes read are returned. | |
141 | */ | |
142 | static ssize_t read_vmcore(struct file *file, char __user *buffer, | |
143 | size_t buflen, loff_t *fpos) | |
144 | { | |
145 | ssize_t acc = 0, tmp; | |
80e8ff63 VG |
146 | size_t tsz; |
147 | u64 start, nr_bytes; | |
666bfddb VG |
148 | struct vmcore *curr_m = NULL; |
149 | ||
150 | if (buflen == 0 || *fpos >= vmcore_size) | |
151 | return 0; | |
152 | ||
153 | /* trim buflen to not go beyond EOF */ | |
154 | if (buflen > vmcore_size - *fpos) | |
155 | buflen = vmcore_size - *fpos; | |
156 | ||
157 | /* Read ELF core header */ | |
158 | if (*fpos < elfcorebuf_sz) { | |
159 | tsz = elfcorebuf_sz - *fpos; | |
160 | if (buflen < tsz) | |
161 | tsz = buflen; | |
162 | if (copy_to_user(buffer, elfcorebuf + *fpos, tsz)) | |
163 | return -EFAULT; | |
164 | buflen -= tsz; | |
165 | *fpos += tsz; | |
166 | buffer += tsz; | |
167 | acc += tsz; | |
168 | ||
169 | /* leave now if filled buffer already */ | |
170 | if (buflen == 0) | |
171 | return acc; | |
172 | } | |
173 | ||
174 | start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m); | |
175 | if (!curr_m) | |
176 | return -EINVAL; | |
177 | if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen) | |
178 | tsz = buflen; | |
179 | ||
180 | /* Calculate left bytes in current memory segment. */ | |
181 | nr_bytes = (curr_m->size - (start - curr_m->paddr)); | |
182 | if (tsz > nr_bytes) | |
183 | tsz = nr_bytes; | |
184 | ||
185 | while (buflen) { | |
186 | tmp = read_from_oldmem(buffer, tsz, &start, 1); | |
187 | if (tmp < 0) | |
188 | return tmp; | |
189 | buflen -= tsz; | |
190 | *fpos += tsz; | |
191 | buffer += tsz; | |
192 | acc += tsz; | |
193 | if (start >= (curr_m->paddr + curr_m->size)) { | |
194 | if (curr_m->list.next == &vmcore_list) | |
195 | return acc; /*EOF*/ | |
196 | curr_m = list_entry(curr_m->list.next, | |
197 | struct vmcore, list); | |
198 | start = curr_m->paddr; | |
199 | } | |
200 | if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen) | |
201 | tsz = buflen; | |
202 | /* Calculate left bytes in current memory segment. */ | |
203 | nr_bytes = (curr_m->size - (start - curr_m->paddr)); | |
204 | if (tsz > nr_bytes) | |
205 | tsz = nr_bytes; | |
206 | } | |
207 | return acc; | |
208 | } | |
209 | ||
5aa140c2 | 210 | static const struct file_operations proc_vmcore_operations = { |
666bfddb | 211 | .read = read_vmcore, |
c227e690 | 212 | .llseek = default_llseek, |
666bfddb VG |
213 | }; |
214 | ||
215 | static struct vmcore* __init get_new_element(void) | |
216 | { | |
2f6d3110 | 217 | return kzalloc(sizeof(struct vmcore), GFP_KERNEL); |
666bfddb VG |
218 | } |
219 | ||
220 | static u64 __init get_vmcore_size_elf64(char *elfptr) | |
221 | { | |
222 | int i; | |
223 | u64 size; | |
224 | Elf64_Ehdr *ehdr_ptr; | |
225 | Elf64_Phdr *phdr_ptr; | |
226 | ||
227 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
228 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); | |
229 | size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr)); | |
230 | for (i = 0; i < ehdr_ptr->e_phnum; i++) { | |
231 | size += phdr_ptr->p_memsz; | |
232 | phdr_ptr++; | |
233 | } | |
234 | return size; | |
235 | } | |
236 | ||
72658e9d VG |
237 | static u64 __init get_vmcore_size_elf32(char *elfptr) |
238 | { | |
239 | int i; | |
240 | u64 size; | |
241 | Elf32_Ehdr *ehdr_ptr; | |
242 | Elf32_Phdr *phdr_ptr; | |
243 | ||
244 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
245 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); | |
246 | size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr)); | |
247 | for (i = 0; i < ehdr_ptr->e_phnum; i++) { | |
248 | size += phdr_ptr->p_memsz; | |
249 | phdr_ptr++; | |
250 | } | |
251 | return size; | |
252 | } | |
253 | ||
666bfddb VG |
254 | /* Merges all the PT_NOTE headers into one. */ |
255 | static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, | |
256 | struct list_head *vc_list) | |
257 | { | |
258 | int i, nr_ptnote=0, rc=0; | |
259 | char *tmp; | |
260 | Elf64_Ehdr *ehdr_ptr; | |
261 | Elf64_Phdr phdr, *phdr_ptr; | |
262 | Elf64_Nhdr *nhdr_ptr; | |
263 | u64 phdr_sz = 0, note_off; | |
264 | ||
265 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
266 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); | |
267 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
268 | int j; | |
269 | void *notes_section; | |
270 | struct vmcore *new; | |
271 | u64 offset, max_sz, sz, real_sz = 0; | |
272 | if (phdr_ptr->p_type != PT_NOTE) | |
273 | continue; | |
274 | nr_ptnote++; | |
275 | max_sz = phdr_ptr->p_memsz; | |
276 | offset = phdr_ptr->p_offset; | |
277 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
278 | if (!notes_section) | |
279 | return -ENOMEM; | |
280 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); | |
281 | if (rc < 0) { | |
282 | kfree(notes_section); | |
283 | return rc; | |
284 | } | |
285 | nhdr_ptr = notes_section; | |
286 | for (j = 0; j < max_sz; j += sz) { | |
287 | if (nhdr_ptr->n_namesz == 0) | |
288 | break; | |
289 | sz = sizeof(Elf64_Nhdr) + | |
290 | ((nhdr_ptr->n_namesz + 3) & ~3) + | |
291 | ((nhdr_ptr->n_descsz + 3) & ~3); | |
292 | real_sz += sz; | |
293 | nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz); | |
294 | } | |
295 | ||
296 | /* Add this contiguous chunk of notes section to vmcore list.*/ | |
297 | new = get_new_element(); | |
298 | if (!new) { | |
299 | kfree(notes_section); | |
300 | return -ENOMEM; | |
301 | } | |
302 | new->paddr = phdr_ptr->p_offset; | |
303 | new->size = real_sz; | |
304 | list_add_tail(&new->list, vc_list); | |
305 | phdr_sz += real_sz; | |
306 | kfree(notes_section); | |
307 | } | |
308 | ||
309 | /* Prepare merged PT_NOTE program header. */ | |
310 | phdr.p_type = PT_NOTE; | |
311 | phdr.p_flags = 0; | |
312 | note_off = sizeof(Elf64_Ehdr) + | |
313 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr); | |
314 | phdr.p_offset = note_off; | |
315 | phdr.p_vaddr = phdr.p_paddr = 0; | |
316 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
317 | phdr.p_align = 0; | |
318 | ||
319 | /* Add merged PT_NOTE program header*/ | |
320 | tmp = elfptr + sizeof(Elf64_Ehdr); | |
321 | memcpy(tmp, &phdr, sizeof(phdr)); | |
322 | tmp += sizeof(phdr); | |
323 | ||
324 | /* Remove unwanted PT_NOTE program headers. */ | |
325 | i = (nr_ptnote - 1) * sizeof(Elf64_Phdr); | |
326 | *elfsz = *elfsz - i; | |
327 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr))); | |
328 | ||
329 | /* Modify e_phnum to reflect merged headers. */ | |
330 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
331 | ||
332 | return 0; | |
333 | } | |
334 | ||
72658e9d VG |
335 | /* Merges all the PT_NOTE headers into one. */ |
336 | static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, | |
337 | struct list_head *vc_list) | |
338 | { | |
339 | int i, nr_ptnote=0, rc=0; | |
340 | char *tmp; | |
341 | Elf32_Ehdr *ehdr_ptr; | |
342 | Elf32_Phdr phdr, *phdr_ptr; | |
343 | Elf32_Nhdr *nhdr_ptr; | |
344 | u64 phdr_sz = 0, note_off; | |
345 | ||
346 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
347 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); | |
348 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
349 | int j; | |
350 | void *notes_section; | |
351 | struct vmcore *new; | |
352 | u64 offset, max_sz, sz, real_sz = 0; | |
353 | if (phdr_ptr->p_type != PT_NOTE) | |
354 | continue; | |
355 | nr_ptnote++; | |
356 | max_sz = phdr_ptr->p_memsz; | |
357 | offset = phdr_ptr->p_offset; | |
358 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
359 | if (!notes_section) | |
360 | return -ENOMEM; | |
361 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); | |
362 | if (rc < 0) { | |
363 | kfree(notes_section); | |
364 | return rc; | |
365 | } | |
366 | nhdr_ptr = notes_section; | |
367 | for (j = 0; j < max_sz; j += sz) { | |
368 | if (nhdr_ptr->n_namesz == 0) | |
369 | break; | |
370 | sz = sizeof(Elf32_Nhdr) + | |
371 | ((nhdr_ptr->n_namesz + 3) & ~3) + | |
372 | ((nhdr_ptr->n_descsz + 3) & ~3); | |
373 | real_sz += sz; | |
374 | nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz); | |
375 | } | |
376 | ||
377 | /* Add this contiguous chunk of notes section to vmcore list.*/ | |
378 | new = get_new_element(); | |
379 | if (!new) { | |
380 | kfree(notes_section); | |
381 | return -ENOMEM; | |
382 | } | |
383 | new->paddr = phdr_ptr->p_offset; | |
384 | new->size = real_sz; | |
385 | list_add_tail(&new->list, vc_list); | |
386 | phdr_sz += real_sz; | |
387 | kfree(notes_section); | |
388 | } | |
389 | ||
390 | /* Prepare merged PT_NOTE program header. */ | |
391 | phdr.p_type = PT_NOTE; | |
392 | phdr.p_flags = 0; | |
393 | note_off = sizeof(Elf32_Ehdr) + | |
394 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr); | |
395 | phdr.p_offset = note_off; | |
396 | phdr.p_vaddr = phdr.p_paddr = 0; | |
397 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
398 | phdr.p_align = 0; | |
399 | ||
400 | /* Add merged PT_NOTE program header*/ | |
401 | tmp = elfptr + sizeof(Elf32_Ehdr); | |
402 | memcpy(tmp, &phdr, sizeof(phdr)); | |
403 | tmp += sizeof(phdr); | |
404 | ||
405 | /* Remove unwanted PT_NOTE program headers. */ | |
406 | i = (nr_ptnote - 1) * sizeof(Elf32_Phdr); | |
407 | *elfsz = *elfsz - i; | |
408 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr))); | |
409 | ||
410 | /* Modify e_phnum to reflect merged headers. */ | |
411 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
412 | ||
413 | return 0; | |
414 | } | |
415 | ||
666bfddb VG |
416 | /* Add memory chunks represented by program headers to vmcore list. Also update |
417 | * the new offset fields of exported program headers. */ | |
418 | static int __init process_ptload_program_headers_elf64(char *elfptr, | |
419 | size_t elfsz, | |
420 | struct list_head *vc_list) | |
421 | { | |
422 | int i; | |
423 | Elf64_Ehdr *ehdr_ptr; | |
424 | Elf64_Phdr *phdr_ptr; | |
425 | loff_t vmcore_off; | |
426 | struct vmcore *new; | |
427 | ||
428 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
429 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ | |
430 | ||
431 | /* First program header is PT_NOTE header. */ | |
432 | vmcore_off = sizeof(Elf64_Ehdr) + | |
433 | (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) + | |
434 | phdr_ptr->p_memsz; /* Note sections */ | |
435 | ||
436 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
437 | if (phdr_ptr->p_type != PT_LOAD) | |
438 | continue; | |
439 | ||
440 | /* Add this contiguous chunk of memory to vmcore list.*/ | |
441 | new = get_new_element(); | |
442 | if (!new) | |
443 | return -ENOMEM; | |
444 | new->paddr = phdr_ptr->p_offset; | |
445 | new->size = phdr_ptr->p_memsz; | |
446 | list_add_tail(&new->list, vc_list); | |
447 | ||
448 | /* Update the program header offset. */ | |
449 | phdr_ptr->p_offset = vmcore_off; | |
450 | vmcore_off = vmcore_off + phdr_ptr->p_memsz; | |
451 | } | |
452 | return 0; | |
453 | } | |
454 | ||
72658e9d VG |
455 | static int __init process_ptload_program_headers_elf32(char *elfptr, |
456 | size_t elfsz, | |
457 | struct list_head *vc_list) | |
458 | { | |
459 | int i; | |
460 | Elf32_Ehdr *ehdr_ptr; | |
461 | Elf32_Phdr *phdr_ptr; | |
462 | loff_t vmcore_off; | |
463 | struct vmcore *new; | |
464 | ||
465 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
466 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ | |
467 | ||
468 | /* First program header is PT_NOTE header. */ | |
469 | vmcore_off = sizeof(Elf32_Ehdr) + | |
470 | (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) + | |
471 | phdr_ptr->p_memsz; /* Note sections */ | |
472 | ||
473 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
474 | if (phdr_ptr->p_type != PT_LOAD) | |
475 | continue; | |
476 | ||
477 | /* Add this contiguous chunk of memory to vmcore list.*/ | |
478 | new = get_new_element(); | |
479 | if (!new) | |
480 | return -ENOMEM; | |
481 | new->paddr = phdr_ptr->p_offset; | |
482 | new->size = phdr_ptr->p_memsz; | |
483 | list_add_tail(&new->list, vc_list); | |
484 | ||
485 | /* Update the program header offset */ | |
486 | phdr_ptr->p_offset = vmcore_off; | |
487 | vmcore_off = vmcore_off + phdr_ptr->p_memsz; | |
488 | } | |
489 | return 0; | |
490 | } | |
491 | ||
666bfddb VG |
492 | /* Sets offset fields of vmcore elements. */ |
493 | static void __init set_vmcore_list_offsets_elf64(char *elfptr, | |
494 | struct list_head *vc_list) | |
495 | { | |
496 | loff_t vmcore_off; | |
497 | Elf64_Ehdr *ehdr_ptr; | |
498 | struct vmcore *m; | |
499 | ||
500 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
501 | ||
502 | /* Skip Elf header and program headers. */ | |
503 | vmcore_off = sizeof(Elf64_Ehdr) + | |
504 | (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr); | |
505 | ||
506 | list_for_each_entry(m, vc_list, list) { | |
507 | m->offset = vmcore_off; | |
508 | vmcore_off += m->size; | |
509 | } | |
510 | } | |
511 | ||
72658e9d VG |
512 | /* Sets offset fields of vmcore elements. */ |
513 | static void __init set_vmcore_list_offsets_elf32(char *elfptr, | |
514 | struct list_head *vc_list) | |
515 | { | |
516 | loff_t vmcore_off; | |
517 | Elf32_Ehdr *ehdr_ptr; | |
518 | struct vmcore *m; | |
519 | ||
520 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
521 | ||
522 | /* Skip Elf header and program headers. */ | |
523 | vmcore_off = sizeof(Elf32_Ehdr) + | |
524 | (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr); | |
525 | ||
526 | list_for_each_entry(m, vc_list, list) { | |
527 | m->offset = vmcore_off; | |
528 | vmcore_off += m->size; | |
529 | } | |
530 | } | |
531 | ||
666bfddb VG |
532 | static int __init parse_crash_elf64_headers(void) |
533 | { | |
534 | int rc=0; | |
535 | Elf64_Ehdr ehdr; | |
536 | u64 addr; | |
537 | ||
538 | addr = elfcorehdr_addr; | |
539 | ||
540 | /* Read Elf header */ | |
541 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0); | |
542 | if (rc < 0) | |
543 | return rc; | |
544 | ||
545 | /* Do some basic Verification. */ | |
546 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
547 | (ehdr.e_type != ET_CORE) || | |
9833c394 | 548 | !vmcore_elf64_check_arch(&ehdr) || |
666bfddb VG |
549 | ehdr.e_ident[EI_CLASS] != ELFCLASS64 || |
550 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
551 | ehdr.e_version != EV_CURRENT || | |
552 | ehdr.e_ehsize != sizeof(Elf64_Ehdr) || | |
553 | ehdr.e_phentsize != sizeof(Elf64_Phdr) || | |
554 | ehdr.e_phnum == 0) { | |
555 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
556 | "sane\n"); | |
557 | return -EINVAL; | |
558 | } | |
559 | ||
560 | /* Read in all elf headers. */ | |
561 | elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr); | |
562 | elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); | |
563 | if (!elfcorebuf) | |
564 | return -ENOMEM; | |
565 | addr = elfcorehdr_addr; | |
566 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); | |
567 | if (rc < 0) { | |
568 | kfree(elfcorebuf); | |
569 | return rc; | |
570 | } | |
571 | ||
572 | /* Merge all PT_NOTE headers into one. */ | |
573 | rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list); | |
574 | if (rc) { | |
575 | kfree(elfcorebuf); | |
576 | return rc; | |
577 | } | |
578 | rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, | |
579 | &vmcore_list); | |
580 | if (rc) { | |
581 | kfree(elfcorebuf); | |
582 | return rc; | |
583 | } | |
584 | set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list); | |
585 | return 0; | |
586 | } | |
587 | ||
72658e9d VG |
588 | static int __init parse_crash_elf32_headers(void) |
589 | { | |
590 | int rc=0; | |
591 | Elf32_Ehdr ehdr; | |
592 | u64 addr; | |
593 | ||
594 | addr = elfcorehdr_addr; | |
595 | ||
596 | /* Read Elf header */ | |
597 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0); | |
598 | if (rc < 0) | |
599 | return rc; | |
600 | ||
601 | /* Do some basic Verification. */ | |
602 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
603 | (ehdr.e_type != ET_CORE) || | |
604 | !elf_check_arch(&ehdr) || | |
605 | ehdr.e_ident[EI_CLASS] != ELFCLASS32|| | |
606 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
607 | ehdr.e_version != EV_CURRENT || | |
608 | ehdr.e_ehsize != sizeof(Elf32_Ehdr) || | |
609 | ehdr.e_phentsize != sizeof(Elf32_Phdr) || | |
610 | ehdr.e_phnum == 0) { | |
611 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
612 | "sane\n"); | |
613 | return -EINVAL; | |
614 | } | |
615 | ||
616 | /* Read in all elf headers. */ | |
617 | elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); | |
618 | elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); | |
619 | if (!elfcorebuf) | |
620 | return -ENOMEM; | |
621 | addr = elfcorehdr_addr; | |
622 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); | |
623 | if (rc < 0) { | |
624 | kfree(elfcorebuf); | |
625 | return rc; | |
626 | } | |
627 | ||
628 | /* Merge all PT_NOTE headers into one. */ | |
629 | rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list); | |
630 | if (rc) { | |
631 | kfree(elfcorebuf); | |
632 | return rc; | |
633 | } | |
634 | rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, | |
635 | &vmcore_list); | |
636 | if (rc) { | |
637 | kfree(elfcorebuf); | |
638 | return rc; | |
639 | } | |
640 | set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list); | |
641 | return 0; | |
642 | } | |
643 | ||
666bfddb VG |
644 | static int __init parse_crash_elf_headers(void) |
645 | { | |
646 | unsigned char e_ident[EI_NIDENT]; | |
647 | u64 addr; | |
648 | int rc=0; | |
649 | ||
650 | addr = elfcorehdr_addr; | |
651 | rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0); | |
652 | if (rc < 0) | |
653 | return rc; | |
654 | if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { | |
655 | printk(KERN_WARNING "Warning: Core image elf header" | |
656 | " not found\n"); | |
657 | return -EINVAL; | |
658 | } | |
659 | ||
660 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
661 | rc = parse_crash_elf64_headers(); | |
662 | if (rc) | |
663 | return rc; | |
664 | ||
665 | /* Determine vmcore size. */ | |
666 | vmcore_size = get_vmcore_size_elf64(elfcorebuf); | |
72658e9d VG |
667 | } else if (e_ident[EI_CLASS] == ELFCLASS32) { |
668 | rc = parse_crash_elf32_headers(); | |
669 | if (rc) | |
670 | return rc; | |
671 | ||
672 | /* Determine vmcore size. */ | |
673 | vmcore_size = get_vmcore_size_elf32(elfcorebuf); | |
666bfddb VG |
674 | } else { |
675 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
676 | " sane\n"); | |
677 | return -EINVAL; | |
678 | } | |
679 | return 0; | |
680 | } | |
681 | ||
682 | /* Init function for vmcore module. */ | |
683 | static int __init vmcore_init(void) | |
684 | { | |
685 | int rc = 0; | |
686 | ||
687 | /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/ | |
85a0ee34 | 688 | if (!(is_vmcore_usable())) |
666bfddb VG |
689 | return rc; |
690 | rc = parse_crash_elf_headers(); | |
691 | if (rc) { | |
692 | printk(KERN_WARNING "Kdump: vmcore not initialized\n"); | |
693 | return rc; | |
694 | } | |
695 | ||
5aa140c2 | 696 | proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations); |
666bfddb VG |
697 | if (proc_vmcore) |
698 | proc_vmcore->size = vmcore_size; | |
699 | return 0; | |
700 | } | |
701 | module_init(vmcore_init) |