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> | |
afeacc8c | 15 | #include <linux/export.h> |
5a0e3ad6 | 16 | #include <linux/slab.h> |
666bfddb VG |
17 | #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 | */ | |
28 | static LIST_HEAD(vmcore_list); | |
29 | ||
30 | /* Stores the pointer to the buffer containing kernel elf core headers. */ | |
31 | static char *elfcorebuf; | |
32 | static size_t elfcorebuf_sz; | |
33 | ||
34 | /* Total size of vmcore file. */ | |
35 | static u64 vmcore_size; | |
36 | ||
5aa140c2 | 37 | static struct proc_dir_entry *proc_vmcore = NULL; |
666bfddb | 38 | |
997c136f OH |
39 | /* |
40 | * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error | |
41 | * The called function has to take care of module refcounting. | |
42 | */ | |
43 | static int (*oldmem_pfn_is_ram)(unsigned long pfn); | |
44 | ||
45 | int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn)) | |
46 | { | |
47 | if (oldmem_pfn_is_ram) | |
48 | return -EBUSY; | |
49 | oldmem_pfn_is_ram = fn; | |
50 | return 0; | |
51 | } | |
52 | EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram); | |
53 | ||
54 | void unregister_oldmem_pfn_is_ram(void) | |
55 | { | |
56 | oldmem_pfn_is_ram = NULL; | |
57 | wmb(); | |
58 | } | |
59 | EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram); | |
60 | ||
61 | static int pfn_is_ram(unsigned long pfn) | |
62 | { | |
63 | int (*fn)(unsigned long pfn); | |
64 | /* pfn is ram unless fn() checks pagetype */ | |
65 | int ret = 1; | |
66 | ||
67 | /* | |
68 | * Ask hypervisor if the pfn is really ram. | |
69 | * A ballooned page contains no data and reading from such a page | |
70 | * will cause high load in the hypervisor. | |
71 | */ | |
72 | fn = oldmem_pfn_is_ram; | |
73 | if (fn) | |
74 | ret = fn(pfn); | |
75 | ||
76 | return ret; | |
77 | } | |
78 | ||
666bfddb VG |
79 | /* Reads a page from the oldmem device from given offset. */ |
80 | static ssize_t read_from_oldmem(char *buf, size_t count, | |
9e9e3941 | 81 | u64 *ppos, int userbuf) |
666bfddb VG |
82 | { |
83 | unsigned long pfn, offset; | |
84 | size_t nr_bytes; | |
85 | ssize_t read = 0, tmp; | |
86 | ||
87 | if (!count) | |
88 | return 0; | |
89 | ||
90 | offset = (unsigned long)(*ppos % PAGE_SIZE); | |
91 | pfn = (unsigned long)(*ppos / PAGE_SIZE); | |
666bfddb VG |
92 | |
93 | do { | |
94 | if (count > (PAGE_SIZE - offset)) | |
95 | nr_bytes = PAGE_SIZE - offset; | |
96 | else | |
97 | nr_bytes = count; | |
98 | ||
997c136f OH |
99 | /* If pfn is not ram, return zeros for sparse dump files */ |
100 | if (pfn_is_ram(pfn) == 0) | |
101 | memset(buf, 0, nr_bytes); | |
102 | else { | |
103 | tmp = copy_oldmem_page(pfn, buf, nr_bytes, | |
104 | offset, userbuf); | |
105 | if (tmp < 0) | |
106 | return tmp; | |
107 | } | |
666bfddb VG |
108 | *ppos += nr_bytes; |
109 | count -= nr_bytes; | |
110 | buf += nr_bytes; | |
111 | read += nr_bytes; | |
112 | ++pfn; | |
113 | offset = 0; | |
114 | } while (count); | |
115 | ||
116 | return read; | |
117 | } | |
118 | ||
119 | /* Maps vmcore file offset to respective physical address in memroy. */ | |
120 | static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list, | |
121 | struct vmcore **m_ptr) | |
122 | { | |
123 | struct vmcore *m; | |
124 | u64 paddr; | |
125 | ||
126 | list_for_each_entry(m, vc_list, list) { | |
127 | u64 start, end; | |
128 | start = m->offset; | |
129 | end = m->offset + m->size - 1; | |
130 | if (offset >= start && offset <= end) { | |
131 | paddr = m->paddr + offset - start; | |
132 | *m_ptr = m; | |
133 | return paddr; | |
134 | } | |
135 | } | |
136 | *m_ptr = NULL; | |
137 | return 0; | |
138 | } | |
139 | ||
140 | /* Read from the ELF header and then the crash dump. On error, negative value is | |
141 | * returned otherwise number of bytes read are returned. | |
142 | */ | |
143 | static ssize_t read_vmcore(struct file *file, char __user *buffer, | |
144 | size_t buflen, loff_t *fpos) | |
145 | { | |
146 | ssize_t acc = 0, tmp; | |
80e8ff63 VG |
147 | size_t tsz; |
148 | u64 start, nr_bytes; | |
666bfddb VG |
149 | struct vmcore *curr_m = NULL; |
150 | ||
151 | if (buflen == 0 || *fpos >= vmcore_size) | |
152 | return 0; | |
153 | ||
154 | /* trim buflen to not go beyond EOF */ | |
155 | if (buflen > vmcore_size - *fpos) | |
156 | buflen = vmcore_size - *fpos; | |
157 | ||
158 | /* Read ELF core header */ | |
159 | if (*fpos < elfcorebuf_sz) { | |
160 | tsz = elfcorebuf_sz - *fpos; | |
161 | if (buflen < tsz) | |
162 | tsz = buflen; | |
163 | if (copy_to_user(buffer, elfcorebuf + *fpos, tsz)) | |
164 | return -EFAULT; | |
165 | buflen -= tsz; | |
166 | *fpos += tsz; | |
167 | buffer += tsz; | |
168 | acc += tsz; | |
169 | ||
170 | /* leave now if filled buffer already */ | |
171 | if (buflen == 0) | |
172 | return acc; | |
173 | } | |
174 | ||
175 | start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m); | |
176 | if (!curr_m) | |
177 | return -EINVAL; | |
178 | if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen) | |
179 | tsz = buflen; | |
180 | ||
181 | /* Calculate left bytes in current memory segment. */ | |
182 | nr_bytes = (curr_m->size - (start - curr_m->paddr)); | |
183 | if (tsz > nr_bytes) | |
184 | tsz = nr_bytes; | |
185 | ||
186 | while (buflen) { | |
187 | tmp = read_from_oldmem(buffer, tsz, &start, 1); | |
188 | if (tmp < 0) | |
189 | return tmp; | |
190 | buflen -= tsz; | |
191 | *fpos += tsz; | |
192 | buffer += tsz; | |
193 | acc += tsz; | |
194 | if (start >= (curr_m->paddr + curr_m->size)) { | |
195 | if (curr_m->list.next == &vmcore_list) | |
196 | return acc; /*EOF*/ | |
197 | curr_m = list_entry(curr_m->list.next, | |
198 | struct vmcore, list); | |
199 | start = curr_m->paddr; | |
200 | } | |
201 | if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen) | |
202 | tsz = buflen; | |
203 | /* Calculate left bytes in current memory segment. */ | |
204 | nr_bytes = (curr_m->size - (start - curr_m->paddr)); | |
205 | if (tsz > nr_bytes) | |
206 | tsz = nr_bytes; | |
207 | } | |
208 | return acc; | |
209 | } | |
210 | ||
5aa140c2 | 211 | static const struct file_operations proc_vmcore_operations = { |
666bfddb | 212 | .read = read_vmcore, |
c227e690 | 213 | .llseek = default_llseek, |
666bfddb VG |
214 | }; |
215 | ||
216 | static struct vmcore* __init get_new_element(void) | |
217 | { | |
2f6d3110 | 218 | return kzalloc(sizeof(struct vmcore), GFP_KERNEL); |
666bfddb VG |
219 | } |
220 | ||
221 | static u64 __init get_vmcore_size_elf64(char *elfptr) | |
222 | { | |
223 | int i; | |
224 | u64 size; | |
225 | Elf64_Ehdr *ehdr_ptr; | |
226 | Elf64_Phdr *phdr_ptr; | |
227 | ||
228 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
229 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); | |
230 | size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr)); | |
231 | for (i = 0; i < ehdr_ptr->e_phnum; i++) { | |
232 | size += phdr_ptr->p_memsz; | |
233 | phdr_ptr++; | |
234 | } | |
235 | return size; | |
236 | } | |
237 | ||
72658e9d VG |
238 | static u64 __init get_vmcore_size_elf32(char *elfptr) |
239 | { | |
240 | int i; | |
241 | u64 size; | |
242 | Elf32_Ehdr *ehdr_ptr; | |
243 | Elf32_Phdr *phdr_ptr; | |
244 | ||
245 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
246 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); | |
247 | size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr)); | |
248 | for (i = 0; i < ehdr_ptr->e_phnum; i++) { | |
249 | size += phdr_ptr->p_memsz; | |
250 | phdr_ptr++; | |
251 | } | |
252 | return size; | |
253 | } | |
254 | ||
666bfddb VG |
255 | /* Merges all the PT_NOTE headers into one. */ |
256 | static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, | |
257 | struct list_head *vc_list) | |
258 | { | |
259 | int i, nr_ptnote=0, rc=0; | |
260 | char *tmp; | |
261 | Elf64_Ehdr *ehdr_ptr; | |
262 | Elf64_Phdr phdr, *phdr_ptr; | |
263 | Elf64_Nhdr *nhdr_ptr; | |
264 | u64 phdr_sz = 0, note_off; | |
265 | ||
266 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
267 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); | |
268 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
269 | int j; | |
270 | void *notes_section; | |
271 | struct vmcore *new; | |
272 | u64 offset, max_sz, sz, real_sz = 0; | |
273 | if (phdr_ptr->p_type != PT_NOTE) | |
274 | continue; | |
275 | nr_ptnote++; | |
276 | max_sz = phdr_ptr->p_memsz; | |
277 | offset = phdr_ptr->p_offset; | |
278 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
279 | if (!notes_section) | |
280 | return -ENOMEM; | |
281 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); | |
282 | if (rc < 0) { | |
283 | kfree(notes_section); | |
284 | return rc; | |
285 | } | |
286 | nhdr_ptr = notes_section; | |
287 | for (j = 0; j < max_sz; j += sz) { | |
288 | if (nhdr_ptr->n_namesz == 0) | |
289 | break; | |
290 | sz = sizeof(Elf64_Nhdr) + | |
291 | ((nhdr_ptr->n_namesz + 3) & ~3) + | |
292 | ((nhdr_ptr->n_descsz + 3) & ~3); | |
293 | real_sz += sz; | |
294 | nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz); | |
295 | } | |
296 | ||
297 | /* Add this contiguous chunk of notes section to vmcore list.*/ | |
298 | new = get_new_element(); | |
299 | if (!new) { | |
300 | kfree(notes_section); | |
301 | return -ENOMEM; | |
302 | } | |
303 | new->paddr = phdr_ptr->p_offset; | |
304 | new->size = real_sz; | |
305 | list_add_tail(&new->list, vc_list); | |
306 | phdr_sz += real_sz; | |
307 | kfree(notes_section); | |
308 | } | |
309 | ||
310 | /* Prepare merged PT_NOTE program header. */ | |
311 | phdr.p_type = PT_NOTE; | |
312 | phdr.p_flags = 0; | |
313 | note_off = sizeof(Elf64_Ehdr) + | |
314 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr); | |
315 | phdr.p_offset = note_off; | |
316 | phdr.p_vaddr = phdr.p_paddr = 0; | |
317 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
318 | phdr.p_align = 0; | |
319 | ||
320 | /* Add merged PT_NOTE program header*/ | |
321 | tmp = elfptr + sizeof(Elf64_Ehdr); | |
322 | memcpy(tmp, &phdr, sizeof(phdr)); | |
323 | tmp += sizeof(phdr); | |
324 | ||
325 | /* Remove unwanted PT_NOTE program headers. */ | |
326 | i = (nr_ptnote - 1) * sizeof(Elf64_Phdr); | |
327 | *elfsz = *elfsz - i; | |
328 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr))); | |
329 | ||
330 | /* Modify e_phnum to reflect merged headers. */ | |
331 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
332 | ||
333 | return 0; | |
334 | } | |
335 | ||
72658e9d VG |
336 | /* Merges all the PT_NOTE headers into one. */ |
337 | static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, | |
338 | struct list_head *vc_list) | |
339 | { | |
340 | int i, nr_ptnote=0, rc=0; | |
341 | char *tmp; | |
342 | Elf32_Ehdr *ehdr_ptr; | |
343 | Elf32_Phdr phdr, *phdr_ptr; | |
344 | Elf32_Nhdr *nhdr_ptr; | |
345 | u64 phdr_sz = 0, note_off; | |
346 | ||
347 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
348 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); | |
349 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
350 | int j; | |
351 | void *notes_section; | |
352 | struct vmcore *new; | |
353 | u64 offset, max_sz, sz, real_sz = 0; | |
354 | if (phdr_ptr->p_type != PT_NOTE) | |
355 | continue; | |
356 | nr_ptnote++; | |
357 | max_sz = phdr_ptr->p_memsz; | |
358 | offset = phdr_ptr->p_offset; | |
359 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
360 | if (!notes_section) | |
361 | return -ENOMEM; | |
362 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); | |
363 | if (rc < 0) { | |
364 | kfree(notes_section); | |
365 | return rc; | |
366 | } | |
367 | nhdr_ptr = notes_section; | |
368 | for (j = 0; j < max_sz; j += sz) { | |
369 | if (nhdr_ptr->n_namesz == 0) | |
370 | break; | |
371 | sz = sizeof(Elf32_Nhdr) + | |
372 | ((nhdr_ptr->n_namesz + 3) & ~3) + | |
373 | ((nhdr_ptr->n_descsz + 3) & ~3); | |
374 | real_sz += sz; | |
375 | nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz); | |
376 | } | |
377 | ||
378 | /* Add this contiguous chunk of notes section to vmcore list.*/ | |
379 | new = get_new_element(); | |
380 | if (!new) { | |
381 | kfree(notes_section); | |
382 | return -ENOMEM; | |
383 | } | |
384 | new->paddr = phdr_ptr->p_offset; | |
385 | new->size = real_sz; | |
386 | list_add_tail(&new->list, vc_list); | |
387 | phdr_sz += real_sz; | |
388 | kfree(notes_section); | |
389 | } | |
390 | ||
391 | /* Prepare merged PT_NOTE program header. */ | |
392 | phdr.p_type = PT_NOTE; | |
393 | phdr.p_flags = 0; | |
394 | note_off = sizeof(Elf32_Ehdr) + | |
395 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr); | |
396 | phdr.p_offset = note_off; | |
397 | phdr.p_vaddr = phdr.p_paddr = 0; | |
398 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
399 | phdr.p_align = 0; | |
400 | ||
401 | /* Add merged PT_NOTE program header*/ | |
402 | tmp = elfptr + sizeof(Elf32_Ehdr); | |
403 | memcpy(tmp, &phdr, sizeof(phdr)); | |
404 | tmp += sizeof(phdr); | |
405 | ||
406 | /* Remove unwanted PT_NOTE program headers. */ | |
407 | i = (nr_ptnote - 1) * sizeof(Elf32_Phdr); | |
408 | *elfsz = *elfsz - i; | |
409 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr))); | |
410 | ||
411 | /* Modify e_phnum to reflect merged headers. */ | |
412 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
413 | ||
414 | return 0; | |
415 | } | |
416 | ||
666bfddb VG |
417 | /* Add memory chunks represented by program headers to vmcore list. Also update |
418 | * the new offset fields of exported program headers. */ | |
419 | static int __init process_ptload_program_headers_elf64(char *elfptr, | |
420 | size_t elfsz, | |
421 | struct list_head *vc_list) | |
422 | { | |
423 | int i; | |
424 | Elf64_Ehdr *ehdr_ptr; | |
425 | Elf64_Phdr *phdr_ptr; | |
426 | loff_t vmcore_off; | |
427 | struct vmcore *new; | |
428 | ||
429 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
430 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ | |
431 | ||
432 | /* First program header is PT_NOTE header. */ | |
433 | vmcore_off = sizeof(Elf64_Ehdr) + | |
434 | (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) + | |
435 | phdr_ptr->p_memsz; /* Note sections */ | |
436 | ||
437 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
438 | if (phdr_ptr->p_type != PT_LOAD) | |
439 | continue; | |
440 | ||
441 | /* Add this contiguous chunk of memory to vmcore list.*/ | |
442 | new = get_new_element(); | |
443 | if (!new) | |
444 | return -ENOMEM; | |
445 | new->paddr = phdr_ptr->p_offset; | |
446 | new->size = phdr_ptr->p_memsz; | |
447 | list_add_tail(&new->list, vc_list); | |
448 | ||
449 | /* Update the program header offset. */ | |
450 | phdr_ptr->p_offset = vmcore_off; | |
451 | vmcore_off = vmcore_off + phdr_ptr->p_memsz; | |
452 | } | |
453 | return 0; | |
454 | } | |
455 | ||
72658e9d VG |
456 | static int __init process_ptload_program_headers_elf32(char *elfptr, |
457 | size_t elfsz, | |
458 | struct list_head *vc_list) | |
459 | { | |
460 | int i; | |
461 | Elf32_Ehdr *ehdr_ptr; | |
462 | Elf32_Phdr *phdr_ptr; | |
463 | loff_t vmcore_off; | |
464 | struct vmcore *new; | |
465 | ||
466 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
467 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ | |
468 | ||
469 | /* First program header is PT_NOTE header. */ | |
470 | vmcore_off = sizeof(Elf32_Ehdr) + | |
471 | (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) + | |
472 | phdr_ptr->p_memsz; /* Note sections */ | |
473 | ||
474 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
475 | if (phdr_ptr->p_type != PT_LOAD) | |
476 | continue; | |
477 | ||
478 | /* Add this contiguous chunk of memory to vmcore list.*/ | |
479 | new = get_new_element(); | |
480 | if (!new) | |
481 | return -ENOMEM; | |
482 | new->paddr = phdr_ptr->p_offset; | |
483 | new->size = phdr_ptr->p_memsz; | |
484 | list_add_tail(&new->list, vc_list); | |
485 | ||
486 | /* Update the program header offset */ | |
487 | phdr_ptr->p_offset = vmcore_off; | |
488 | vmcore_off = vmcore_off + phdr_ptr->p_memsz; | |
489 | } | |
490 | return 0; | |
491 | } | |
492 | ||
666bfddb VG |
493 | /* Sets offset fields of vmcore elements. */ |
494 | static void __init set_vmcore_list_offsets_elf64(char *elfptr, | |
495 | struct list_head *vc_list) | |
496 | { | |
497 | loff_t vmcore_off; | |
498 | Elf64_Ehdr *ehdr_ptr; | |
499 | struct vmcore *m; | |
500 | ||
501 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
502 | ||
503 | /* Skip Elf header and program headers. */ | |
504 | vmcore_off = sizeof(Elf64_Ehdr) + | |
505 | (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr); | |
506 | ||
507 | list_for_each_entry(m, vc_list, list) { | |
508 | m->offset = vmcore_off; | |
509 | vmcore_off += m->size; | |
510 | } | |
511 | } | |
512 | ||
72658e9d VG |
513 | /* Sets offset fields of vmcore elements. */ |
514 | static void __init set_vmcore_list_offsets_elf32(char *elfptr, | |
515 | struct list_head *vc_list) | |
516 | { | |
517 | loff_t vmcore_off; | |
518 | Elf32_Ehdr *ehdr_ptr; | |
519 | struct vmcore *m; | |
520 | ||
521 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
522 | ||
523 | /* Skip Elf header and program headers. */ | |
524 | vmcore_off = sizeof(Elf32_Ehdr) + | |
525 | (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr); | |
526 | ||
527 | list_for_each_entry(m, vc_list, list) { | |
528 | m->offset = vmcore_off; | |
529 | vmcore_off += m->size; | |
530 | } | |
531 | } | |
532 | ||
666bfddb VG |
533 | static int __init parse_crash_elf64_headers(void) |
534 | { | |
535 | int rc=0; | |
536 | Elf64_Ehdr ehdr; | |
537 | u64 addr; | |
538 | ||
539 | addr = elfcorehdr_addr; | |
540 | ||
541 | /* Read Elf header */ | |
542 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0); | |
543 | if (rc < 0) | |
544 | return rc; | |
545 | ||
546 | /* Do some basic Verification. */ | |
547 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
548 | (ehdr.e_type != ET_CORE) || | |
9833c394 | 549 | !vmcore_elf64_check_arch(&ehdr) || |
666bfddb VG |
550 | ehdr.e_ident[EI_CLASS] != ELFCLASS64 || |
551 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
552 | ehdr.e_version != EV_CURRENT || | |
553 | ehdr.e_ehsize != sizeof(Elf64_Ehdr) || | |
554 | ehdr.e_phentsize != sizeof(Elf64_Phdr) || | |
555 | ehdr.e_phnum == 0) { | |
556 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
557 | "sane\n"); | |
558 | return -EINVAL; | |
559 | } | |
560 | ||
561 | /* Read in all elf headers. */ | |
562 | elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr); | |
563 | elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); | |
564 | if (!elfcorebuf) | |
565 | return -ENOMEM; | |
566 | addr = elfcorehdr_addr; | |
567 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); | |
568 | if (rc < 0) { | |
569 | kfree(elfcorebuf); | |
570 | return rc; | |
571 | } | |
572 | ||
573 | /* Merge all PT_NOTE headers into one. */ | |
574 | rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list); | |
575 | if (rc) { | |
576 | kfree(elfcorebuf); | |
577 | return rc; | |
578 | } | |
579 | rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, | |
580 | &vmcore_list); | |
581 | if (rc) { | |
582 | kfree(elfcorebuf); | |
583 | return rc; | |
584 | } | |
585 | set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list); | |
586 | return 0; | |
587 | } | |
588 | ||
72658e9d VG |
589 | static int __init parse_crash_elf32_headers(void) |
590 | { | |
591 | int rc=0; | |
592 | Elf32_Ehdr ehdr; | |
593 | u64 addr; | |
594 | ||
595 | addr = elfcorehdr_addr; | |
596 | ||
597 | /* Read Elf header */ | |
598 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0); | |
599 | if (rc < 0) | |
600 | return rc; | |
601 | ||
602 | /* Do some basic Verification. */ | |
603 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
604 | (ehdr.e_type != ET_CORE) || | |
605 | !elf_check_arch(&ehdr) || | |
606 | ehdr.e_ident[EI_CLASS] != ELFCLASS32|| | |
607 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
608 | ehdr.e_version != EV_CURRENT || | |
609 | ehdr.e_ehsize != sizeof(Elf32_Ehdr) || | |
610 | ehdr.e_phentsize != sizeof(Elf32_Phdr) || | |
611 | ehdr.e_phnum == 0) { | |
612 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
613 | "sane\n"); | |
614 | return -EINVAL; | |
615 | } | |
616 | ||
617 | /* Read in all elf headers. */ | |
618 | elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); | |
619 | elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); | |
620 | if (!elfcorebuf) | |
621 | return -ENOMEM; | |
622 | addr = elfcorehdr_addr; | |
623 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); | |
624 | if (rc < 0) { | |
625 | kfree(elfcorebuf); | |
626 | return rc; | |
627 | } | |
628 | ||
629 | /* Merge all PT_NOTE headers into one. */ | |
630 | rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list); | |
631 | if (rc) { | |
632 | kfree(elfcorebuf); | |
633 | return rc; | |
634 | } | |
635 | rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, | |
636 | &vmcore_list); | |
637 | if (rc) { | |
638 | kfree(elfcorebuf); | |
639 | return rc; | |
640 | } | |
641 | set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list); | |
642 | return 0; | |
643 | } | |
644 | ||
666bfddb VG |
645 | static int __init parse_crash_elf_headers(void) |
646 | { | |
647 | unsigned char e_ident[EI_NIDENT]; | |
648 | u64 addr; | |
649 | int rc=0; | |
650 | ||
651 | addr = elfcorehdr_addr; | |
652 | rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0); | |
653 | if (rc < 0) | |
654 | return rc; | |
655 | if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { | |
656 | printk(KERN_WARNING "Warning: Core image elf header" | |
657 | " not found\n"); | |
658 | return -EINVAL; | |
659 | } | |
660 | ||
661 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
662 | rc = parse_crash_elf64_headers(); | |
663 | if (rc) | |
664 | return rc; | |
665 | ||
666 | /* Determine vmcore size. */ | |
667 | vmcore_size = get_vmcore_size_elf64(elfcorebuf); | |
72658e9d VG |
668 | } else if (e_ident[EI_CLASS] == ELFCLASS32) { |
669 | rc = parse_crash_elf32_headers(); | |
670 | if (rc) | |
671 | return rc; | |
672 | ||
673 | /* Determine vmcore size. */ | |
674 | vmcore_size = get_vmcore_size_elf32(elfcorebuf); | |
666bfddb VG |
675 | } else { |
676 | printk(KERN_WARNING "Warning: Core image elf header is not" | |
677 | " sane\n"); | |
678 | return -EINVAL; | |
679 | } | |
680 | return 0; | |
681 | } | |
682 | ||
683 | /* Init function for vmcore module. */ | |
684 | static int __init vmcore_init(void) | |
685 | { | |
686 | int rc = 0; | |
687 | ||
688 | /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/ | |
85a0ee34 | 689 | if (!(is_vmcore_usable())) |
666bfddb VG |
690 | return rc; |
691 | rc = parse_crash_elf_headers(); | |
692 | if (rc) { | |
693 | printk(KERN_WARNING "Kdump: vmcore not initialized\n"); | |
694 | return rc; | |
695 | } | |
696 | ||
5aa140c2 | 697 | proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations); |
666bfddb VG |
698 | if (proc_vmcore) |
699 | proc_vmcore->size = vmcore_size; | |
700 | return 0; | |
701 | } | |
702 | module_init(vmcore_init) |