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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
666bfddb VG |
2 | /* |
3 | * fs/proc/vmcore.c Interface for accessing the crash | |
4 | * dump from the system's previous life. | |
5 | * Heavily borrowed from fs/proc/kcore.c | |
6 | * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) | |
7 | * Copyright (C) IBM Corporation, 2004. All rights reserved | |
8 | * | |
9 | */ | |
10 | ||
666bfddb | 11 | #include <linux/mm.h> |
2f96b8c1 | 12 | #include <linux/kcore.h> |
666bfddb | 13 | #include <linux/user.h> |
666bfddb VG |
14 | #include <linux/elf.h> |
15 | #include <linux/elfcore.h> | |
afeacc8c | 16 | #include <linux/export.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
666bfddb | 18 | #include <linux/highmem.h> |
87ebdc00 | 19 | #include <linux/printk.h> |
57c8a661 | 20 | #include <linux/memblock.h> |
666bfddb VG |
21 | #include <linux/init.h> |
22 | #include <linux/crash_dump.h> | |
23 | #include <linux/list.h> | |
c6c40533 | 24 | #include <linux/moduleparam.h> |
2724273e | 25 | #include <linux/mutex.h> |
83086978 | 26 | #include <linux/vmalloc.h> |
9cb21813 | 27 | #include <linux/pagemap.h> |
5d8de293 | 28 | #include <linux/uio.h> |
e9d1d2bb | 29 | #include <linux/cc_platform.h> |
666bfddb | 30 | #include <asm/io.h> |
2f96b8c1 | 31 | #include "internal.h" |
666bfddb VG |
32 | |
33 | /* List representing chunks of contiguous memory areas and their offsets in | |
34 | * vmcore file. | |
35 | */ | |
36 | static LIST_HEAD(vmcore_list); | |
37 | ||
38 | /* Stores the pointer to the buffer containing kernel elf core headers. */ | |
39 | static char *elfcorebuf; | |
40 | static size_t elfcorebuf_sz; | |
f2bdacdd | 41 | static size_t elfcorebuf_sz_orig; |
666bfddb | 42 | |
087350c9 HD |
43 | static char *elfnotes_buf; |
44 | static size_t elfnotes_sz; | |
7efe48df RL |
45 | /* Size of all notes minus the device dump notes */ |
46 | static size_t elfnotes_orig_sz; | |
087350c9 | 47 | |
666bfddb VG |
48 | /* Total size of vmcore file. */ |
49 | static u64 vmcore_size; | |
50 | ||
a05e16ad | 51 | static struct proc_dir_entry *proc_vmcore; |
666bfddb | 52 | |
2724273e RL |
53 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
54 | /* Device Dump list and mutex to synchronize access to list */ | |
55 | static LIST_HEAD(vmcoredd_list); | |
56 | static DEFINE_MUTEX(vmcoredd_mutex); | |
c6c40533 KS |
57 | |
58 | static bool vmcoredd_disabled; | |
59 | core_param(novmcoredd, vmcoredd_disabled, bool, 0); | |
2724273e RL |
60 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ |
61 | ||
7efe48df RL |
62 | /* Device Dump Size */ |
63 | static size_t vmcoredd_orig_sz; | |
64 | ||
5039b170 DH |
65 | static DEFINE_SPINLOCK(vmcore_cb_lock); |
66 | DEFINE_STATIC_SRCU(vmcore_cb_srcu); | |
cc5f2704 DH |
67 | /* List of registered vmcore callbacks. */ |
68 | static LIST_HEAD(vmcore_cb_list); | |
cc5f2704 DH |
69 | /* Whether the vmcore has been opened once. */ |
70 | static bool vmcore_opened; | |
71 | ||
72 | void register_vmcore_cb(struct vmcore_cb *cb) | |
997c136f | 73 | { |
cc5f2704 | 74 | INIT_LIST_HEAD(&cb->next); |
5039b170 | 75 | spin_lock(&vmcore_cb_lock); |
cc5f2704 DH |
76 | list_add_tail(&cb->next, &vmcore_cb_list); |
77 | /* | |
78 | * Registering a vmcore callback after the vmcore was opened is | |
79 | * very unusual (e.g., manual driver loading). | |
80 | */ | |
81 | if (vmcore_opened) | |
82 | pr_warn_once("Unexpected vmcore callback registration\n"); | |
5039b170 | 83 | spin_unlock(&vmcore_cb_lock); |
997c136f | 84 | } |
cc5f2704 | 85 | EXPORT_SYMBOL_GPL(register_vmcore_cb); |
997c136f | 86 | |
cc5f2704 | 87 | void unregister_vmcore_cb(struct vmcore_cb *cb) |
997c136f | 88 | { |
5039b170 DH |
89 | spin_lock(&vmcore_cb_lock); |
90 | list_del_rcu(&cb->next); | |
cc5f2704 DH |
91 | /* |
92 | * Unregistering a vmcore callback after the vmcore was opened is | |
93 | * very unusual (e.g., forced driver removal), but we cannot stop | |
94 | * unregistering. | |
95 | */ | |
25bc5b0d | 96 | if (vmcore_opened) |
cc5f2704 | 97 | pr_warn_once("Unexpected vmcore callback unregistration\n"); |
5039b170 DH |
98 | spin_unlock(&vmcore_cb_lock); |
99 | ||
100 | synchronize_srcu(&vmcore_cb_srcu); | |
997c136f | 101 | } |
cc5f2704 | 102 | EXPORT_SYMBOL_GPL(unregister_vmcore_cb); |
997c136f | 103 | |
2c9feeae | 104 | static bool pfn_is_ram(unsigned long pfn) |
997c136f | 105 | { |
cc5f2704 | 106 | struct vmcore_cb *cb; |
2c9feeae | 107 | bool ret = true; |
997c136f | 108 | |
5039b170 DH |
109 | list_for_each_entry_srcu(cb, &vmcore_cb_list, next, |
110 | srcu_read_lock_held(&vmcore_cb_srcu)) { | |
cc5f2704 DH |
111 | if (unlikely(!cb->pfn_is_ram)) |
112 | continue; | |
113 | ret = cb->pfn_is_ram(cb, pfn); | |
114 | if (!ret) | |
115 | break; | |
116 | } | |
997c136f OH |
117 | |
118 | return ret; | |
119 | } | |
120 | ||
cc5f2704 DH |
121 | static int open_vmcore(struct inode *inode, struct file *file) |
122 | { | |
5039b170 | 123 | spin_lock(&vmcore_cb_lock); |
cc5f2704 | 124 | vmcore_opened = true; |
5039b170 | 125 | spin_unlock(&vmcore_cb_lock); |
cc5f2704 DH |
126 | |
127 | return 0; | |
128 | } | |
129 | ||
666bfddb | 130 | /* Reads a page from the oldmem device from given offset. */ |
e0690479 | 131 | ssize_t read_from_oldmem(struct iov_iter *iter, size_t count, |
5d8de293 | 132 | u64 *ppos, bool encrypted) |
666bfddb VG |
133 | { |
134 | unsigned long pfn, offset; | |
641db40f | 135 | ssize_t nr_bytes; |
666bfddb | 136 | ssize_t read = 0, tmp; |
5039b170 | 137 | int idx; |
666bfddb VG |
138 | |
139 | if (!count) | |
140 | return 0; | |
141 | ||
142 | offset = (unsigned long)(*ppos % PAGE_SIZE); | |
143 | pfn = (unsigned long)(*ppos / PAGE_SIZE); | |
666bfddb | 144 | |
5039b170 | 145 | idx = srcu_read_lock(&vmcore_cb_srcu); |
666bfddb VG |
146 | do { |
147 | if (count > (PAGE_SIZE - offset)) | |
148 | nr_bytes = PAGE_SIZE - offset; | |
149 | else | |
150 | nr_bytes = count; | |
151 | ||
997c136f | 152 | /* If pfn is not ram, return zeros for sparse dump files */ |
c1e63117 | 153 | if (!pfn_is_ram(pfn)) { |
5d8de293 | 154 | tmp = iov_iter_zero(nr_bytes, iter); |
c1e63117 | 155 | } else { |
992b649a | 156 | if (encrypted) |
5d8de293 | 157 | tmp = copy_oldmem_page_encrypted(iter, pfn, |
992b649a | 158 | nr_bytes, |
5d8de293 | 159 | offset); |
992b649a | 160 | else |
5d8de293 MWO |
161 | tmp = copy_oldmem_page(iter, pfn, nr_bytes, |
162 | offset); | |
997c136f | 163 | } |
5d8de293 | 164 | if (tmp < nr_bytes) { |
5039b170 | 165 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
5d8de293 | 166 | return -EFAULT; |
c1e63117 DH |
167 | } |
168 | ||
666bfddb VG |
169 | *ppos += nr_bytes; |
170 | count -= nr_bytes; | |
666bfddb VG |
171 | read += nr_bytes; |
172 | ++pfn; | |
173 | offset = 0; | |
174 | } while (count); | |
5039b170 | 175 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
666bfddb VG |
176 | |
177 | return read; | |
178 | } | |
179 | ||
be8a8d06 MH |
180 | /* |
181 | * Architectures may override this function to allocate ELF header in 2nd kernel | |
182 | */ | |
183 | int __weak elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) | |
184 | { | |
185 | return 0; | |
186 | } | |
187 | ||
188 | /* | |
189 | * Architectures may override this function to free header | |
190 | */ | |
191 | void __weak elfcorehdr_free(unsigned long long addr) | |
192 | {} | |
193 | ||
194 | /* | |
195 | * Architectures may override this function to read from ELF header | |
196 | */ | |
197 | ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos) | |
198 | { | |
e0690479 MWO |
199 | struct kvec kvec = { .iov_base = buf, .iov_len = count }; |
200 | struct iov_iter iter; | |
201 | ||
de4eda9d | 202 | iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count); |
e0690479 MWO |
203 | |
204 | return read_from_oldmem(&iter, count, ppos, false); | |
be8a8d06 MH |
205 | } |
206 | ||
207 | /* | |
208 | * Architectures may override this function to read from notes sections | |
209 | */ | |
210 | ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) | |
211 | { | |
e0690479 MWO |
212 | struct kvec kvec = { .iov_base = buf, .iov_len = count }; |
213 | struct iov_iter iter; | |
214 | ||
de4eda9d | 215 | iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count); |
e0690479 MWO |
216 | |
217 | return read_from_oldmem(&iter, count, ppos, | |
218 | cc_platform_has(CC_ATTR_MEM_ENCRYPT)); | |
be8a8d06 MH |
219 | } |
220 | ||
9cb21813 MH |
221 | /* |
222 | * Architectures may override this function to map oldmem | |
223 | */ | |
224 | int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma, | |
225 | unsigned long from, unsigned long pfn, | |
226 | unsigned long size, pgprot_t prot) | |
227 | { | |
992b649a | 228 | prot = pgprot_encrypted(prot); |
9cb21813 MH |
229 | return remap_pfn_range(vma, from, pfn, size, prot); |
230 | } | |
231 | ||
cf089611 BP |
232 | /* |
233 | * Architectures which support memory encryption override this. | |
234 | */ | |
5d8de293 MWO |
235 | ssize_t __weak copy_oldmem_page_encrypted(struct iov_iter *iter, |
236 | unsigned long pfn, size_t csize, unsigned long offset) | |
cf089611 | 237 | { |
5d8de293 | 238 | return copy_oldmem_page(iter, pfn, csize, offset); |
cf089611 BP |
239 | } |
240 | ||
7efe48df | 241 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
4a22fd20 | 242 | static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size) |
7efe48df RL |
243 | { |
244 | struct vmcoredd_node *dump; | |
245 | u64 offset = 0; | |
246 | int ret = 0; | |
247 | size_t tsz; | |
248 | char *buf; | |
249 | ||
250 | mutex_lock(&vmcoredd_mutex); | |
251 | list_for_each_entry(dump, &vmcoredd_list, list) { | |
252 | if (start < offset + dump->size) { | |
253 | tsz = min(offset + (u64)dump->size - start, (u64)size); | |
254 | buf = dump->buf + start - offset; | |
4a22fd20 | 255 | if (copy_to_iter(buf, tsz, iter) < tsz) { |
7efe48df RL |
256 | ret = -EFAULT; |
257 | goto out_unlock; | |
258 | } | |
259 | ||
260 | size -= tsz; | |
261 | start += tsz; | |
7efe48df RL |
262 | |
263 | /* Leave now if buffer filled already */ | |
264 | if (!size) | |
265 | goto out_unlock; | |
266 | } | |
267 | offset += dump->size; | |
268 | } | |
269 | ||
270 | out_unlock: | |
271 | mutex_unlock(&vmcoredd_mutex); | |
272 | return ret; | |
273 | } | |
274 | ||
a2036a1e | 275 | #ifdef CONFIG_MMU |
7efe48df RL |
276 | static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst, |
277 | u64 start, size_t size) | |
278 | { | |
279 | struct vmcoredd_node *dump; | |
280 | u64 offset = 0; | |
281 | int ret = 0; | |
282 | size_t tsz; | |
283 | char *buf; | |
284 | ||
285 | mutex_lock(&vmcoredd_mutex); | |
286 | list_for_each_entry(dump, &vmcoredd_list, list) { | |
287 | if (start < offset + dump->size) { | |
288 | tsz = min(offset + (u64)dump->size - start, (u64)size); | |
289 | buf = dump->buf + start - offset; | |
bdebd6a2 JH |
290 | if (remap_vmalloc_range_partial(vma, dst, buf, 0, |
291 | tsz)) { | |
7efe48df RL |
292 | ret = -EFAULT; |
293 | goto out_unlock; | |
294 | } | |
295 | ||
296 | size -= tsz; | |
297 | start += tsz; | |
298 | dst += tsz; | |
299 | ||
300 | /* Leave now if buffer filled already */ | |
301 | if (!size) | |
302 | goto out_unlock; | |
303 | } | |
304 | offset += dump->size; | |
305 | } | |
306 | ||
307 | out_unlock: | |
308 | mutex_unlock(&vmcoredd_mutex); | |
309 | return ret; | |
310 | } | |
a2036a1e | 311 | #endif /* CONFIG_MMU */ |
7efe48df RL |
312 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ |
313 | ||
666bfddb VG |
314 | /* Read from the ELF header and then the crash dump. On error, negative value is |
315 | * returned otherwise number of bytes read are returned. | |
316 | */ | |
4a22fd20 | 317 | static ssize_t __read_vmcore(struct iov_iter *iter, loff_t *fpos) |
666bfddb VG |
318 | { |
319 | ssize_t acc = 0, tmp; | |
80e8ff63 | 320 | size_t tsz; |
b27eb186 HD |
321 | u64 start; |
322 | struct vmcore *m = NULL; | |
666bfddb | 323 | |
4a22fd20 | 324 | if (!iov_iter_count(iter) || *fpos >= vmcore_size) |
666bfddb VG |
325 | return 0; |
326 | ||
4a22fd20 | 327 | iov_iter_truncate(iter, vmcore_size - *fpos); |
666bfddb VG |
328 | |
329 | /* Read ELF core header */ | |
330 | if (*fpos < elfcorebuf_sz) { | |
4a22fd20 MWO |
331 | tsz = min(elfcorebuf_sz - (size_t)*fpos, iov_iter_count(iter)); |
332 | if (copy_to_iter(elfcorebuf + *fpos, tsz, iter) < tsz) | |
666bfddb | 333 | return -EFAULT; |
666bfddb | 334 | *fpos += tsz; |
666bfddb VG |
335 | acc += tsz; |
336 | ||
337 | /* leave now if filled buffer already */ | |
4a22fd20 | 338 | if (!iov_iter_count(iter)) |
666bfddb VG |
339 | return acc; |
340 | } | |
341 | ||
70e79866 | 342 | /* Read ELF note segment */ |
087350c9 HD |
343 | if (*fpos < elfcorebuf_sz + elfnotes_sz) { |
344 | void *kaddr; | |
345 | ||
7efe48df RL |
346 | /* We add device dumps before other elf notes because the |
347 | * other elf notes may not fill the elf notes buffer | |
348 | * completely and we will end up with zero-filled data | |
349 | * between the elf notes and the device dumps. Tools will | |
350 | * then try to decode this zero-filled data as valid notes | |
351 | * and we don't want that. Hence, adding device dumps before | |
352 | * the other elf notes ensure that zero-filled data can be | |
353 | * avoided. | |
354 | */ | |
355 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
356 | /* Read device dumps */ | |
357 | if (*fpos < elfcorebuf_sz + vmcoredd_orig_sz) { | |
358 | tsz = min(elfcorebuf_sz + vmcoredd_orig_sz - | |
4a22fd20 | 359 | (size_t)*fpos, iov_iter_count(iter)); |
7efe48df | 360 | start = *fpos - elfcorebuf_sz; |
4a22fd20 | 361 | if (vmcoredd_copy_dumps(iter, start, tsz)) |
7efe48df RL |
362 | return -EFAULT; |
363 | ||
7efe48df | 364 | *fpos += tsz; |
7efe48df RL |
365 | acc += tsz; |
366 | ||
367 | /* leave now if filled buffer already */ | |
4a22fd20 | 368 | if (!iov_iter_count(iter)) |
7efe48df RL |
369 | return acc; |
370 | } | |
371 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
372 | ||
373 | /* Read remaining elf notes */ | |
4a22fd20 MWO |
374 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, |
375 | iov_iter_count(iter)); | |
7efe48df | 376 | kaddr = elfnotes_buf + *fpos - elfcorebuf_sz - vmcoredd_orig_sz; |
4a22fd20 | 377 | if (copy_to_iter(kaddr, tsz, iter) < tsz) |
087350c9 | 378 | return -EFAULT; |
7efe48df | 379 | |
087350c9 | 380 | *fpos += tsz; |
087350c9 HD |
381 | acc += tsz; |
382 | ||
383 | /* leave now if filled buffer already */ | |
4a22fd20 | 384 | if (!iov_iter_count(iter)) |
087350c9 | 385 | return acc; |
5cbcb62d RR |
386 | |
387 | cond_resched(); | |
087350c9 HD |
388 | } |
389 | ||
b27eb186 HD |
390 | list_for_each_entry(m, &vmcore_list, list) { |
391 | if (*fpos < m->offset + m->size) { | |
0b50a2d8 DY |
392 | tsz = (size_t)min_t(unsigned long long, |
393 | m->offset + m->size - *fpos, | |
4a22fd20 | 394 | iov_iter_count(iter)); |
b27eb186 | 395 | start = m->paddr + *fpos - m->offset; |
e0690479 | 396 | tmp = read_from_oldmem(iter, tsz, &start, |
4a22fd20 | 397 | cc_platform_has(CC_ATTR_MEM_ENCRYPT)); |
b27eb186 HD |
398 | if (tmp < 0) |
399 | return tmp; | |
b27eb186 | 400 | *fpos += tsz; |
b27eb186 HD |
401 | acc += tsz; |
402 | ||
403 | /* leave now if filled buffer already */ | |
4a22fd20 | 404 | if (!iov_iter_count(iter)) |
b27eb186 | 405 | return acc; |
666bfddb | 406 | } |
666bfddb | 407 | } |
b27eb186 | 408 | |
666bfddb VG |
409 | return acc; |
410 | } | |
411 | ||
4a22fd20 | 412 | static ssize_t read_vmcore(struct kiocb *iocb, struct iov_iter *iter) |
9cb21813 | 413 | { |
4a22fd20 | 414 | return __read_vmcore(iter, &iocb->ki_pos); |
9cb21813 MH |
415 | } |
416 | ||
417 | /* | |
418 | * The vmcore fault handler uses the page cache and fills data using the | |
4a22fd20 | 419 | * standard __read_vmcore() function. |
9cb21813 MH |
420 | * |
421 | * On s390 the fault handler is used for memory regions that can't be mapped | |
422 | * directly with remap_pfn_range(). | |
423 | */ | |
36f06204 | 424 | static vm_fault_t mmap_vmcore_fault(struct vm_fault *vmf) |
9cb21813 MH |
425 | { |
426 | #ifdef CONFIG_S390 | |
11bac800 | 427 | struct address_space *mapping = vmf->vma->vm_file->f_mapping; |
9cb21813 | 428 | pgoff_t index = vmf->pgoff; |
4a22fd20 MWO |
429 | struct iov_iter iter; |
430 | struct kvec kvec; | |
9cb21813 MH |
431 | struct page *page; |
432 | loff_t offset; | |
9cb21813 MH |
433 | int rc; |
434 | ||
435 | page = find_or_create_page(mapping, index, GFP_KERNEL); | |
436 | if (!page) | |
437 | return VM_FAULT_OOM; | |
438 | if (!PageUptodate(page)) { | |
09cbfeaf | 439 | offset = (loff_t) index << PAGE_SHIFT; |
4a22fd20 MWO |
440 | kvec.iov_base = page_address(page); |
441 | kvec.iov_len = PAGE_SIZE; | |
de4eda9d | 442 | iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, PAGE_SIZE); |
4a22fd20 MWO |
443 | |
444 | rc = __read_vmcore(&iter, &offset); | |
9cb21813 MH |
445 | if (rc < 0) { |
446 | unlock_page(page); | |
09cbfeaf | 447 | put_page(page); |
b5c21237 | 448 | return vmf_error(rc); |
9cb21813 MH |
449 | } |
450 | SetPageUptodate(page); | |
451 | } | |
452 | unlock_page(page); | |
453 | vmf->page = page; | |
454 | return 0; | |
455 | #else | |
456 | return VM_FAULT_SIGBUS; | |
457 | #endif | |
458 | } | |
459 | ||
460 | static const struct vm_operations_struct vmcore_mmap_ops = { | |
461 | .fault = mmap_vmcore_fault, | |
462 | }; | |
463 | ||
83086978 | 464 | /** |
2724273e | 465 | * vmcore_alloc_buf - allocate buffer in vmalloc memory |
e9f5d101 | 466 | * @size: size of buffer |
83086978 HD |
467 | * |
468 | * If CONFIG_MMU is defined, use vmalloc_user() to allow users to mmap | |
469 | * the buffer to user-space by means of remap_vmalloc_range(). | |
470 | * | |
471 | * If CONFIG_MMU is not defined, use vzalloc() since mmap_vmcore() is | |
472 | * disabled and there's no need to allow users to mmap the buffer. | |
473 | */ | |
2724273e | 474 | static inline char *vmcore_alloc_buf(size_t size) |
83086978 HD |
475 | { |
476 | #ifdef CONFIG_MMU | |
2724273e | 477 | return vmalloc_user(size); |
83086978 | 478 | #else |
2724273e | 479 | return vzalloc(size); |
83086978 HD |
480 | #endif |
481 | } | |
482 | ||
483 | /* | |
484 | * Disable mmap_vmcore() if CONFIG_MMU is not defined. MMU is | |
485 | * essential for mmap_vmcore() in order to map physically | |
486 | * non-contiguous objects (ELF header, ELF note segment and memory | |
487 | * regions in the 1st kernel pointed to by PT_LOAD entries) into | |
488 | * virtually contiguous user-space in ELF layout. | |
489 | */ | |
11e376a3 | 490 | #ifdef CONFIG_MMU |
0692dedc VK |
491 | /* |
492 | * remap_oldmem_pfn_checked - do remap_oldmem_pfn_range replacing all pages | |
493 | * reported as not being ram with the zero page. | |
494 | * | |
495 | * @vma: vm_area_struct describing requested mapping | |
496 | * @from: start remapping from | |
497 | * @pfn: page frame number to start remapping to | |
498 | * @size: remapping size | |
499 | * @prot: protection bits | |
500 | * | |
501 | * Returns zero on success, -EAGAIN on failure. | |
502 | */ | |
503 | static int remap_oldmem_pfn_checked(struct vm_area_struct *vma, | |
504 | unsigned long from, unsigned long pfn, | |
505 | unsigned long size, pgprot_t prot) | |
506 | { | |
507 | unsigned long map_size; | |
508 | unsigned long pos_start, pos_end, pos; | |
509 | unsigned long zeropage_pfn = my_zero_pfn(0); | |
510 | size_t len = 0; | |
511 | ||
512 | pos_start = pfn; | |
513 | pos_end = pfn + (size >> PAGE_SHIFT); | |
514 | ||
515 | for (pos = pos_start; pos < pos_end; ++pos) { | |
516 | if (!pfn_is_ram(pos)) { | |
517 | /* | |
518 | * We hit a page which is not ram. Remap the continuous | |
519 | * region between pos_start and pos-1 and replace | |
520 | * the non-ram page at pos with the zero page. | |
521 | */ | |
522 | if (pos > pos_start) { | |
523 | /* Remap continuous region */ | |
524 | map_size = (pos - pos_start) << PAGE_SHIFT; | |
525 | if (remap_oldmem_pfn_range(vma, from + len, | |
526 | pos_start, map_size, | |
527 | prot)) | |
528 | goto fail; | |
529 | len += map_size; | |
530 | } | |
531 | /* Remap the zero page */ | |
532 | if (remap_oldmem_pfn_range(vma, from + len, | |
533 | zeropage_pfn, | |
534 | PAGE_SIZE, prot)) | |
535 | goto fail; | |
536 | len += PAGE_SIZE; | |
537 | pos_start = pos + 1; | |
538 | } | |
539 | } | |
540 | if (pos > pos_start) { | |
541 | /* Remap the rest */ | |
542 | map_size = (pos - pos_start) << PAGE_SHIFT; | |
543 | if (remap_oldmem_pfn_range(vma, from + len, pos_start, | |
544 | map_size, prot)) | |
545 | goto fail; | |
546 | } | |
547 | return 0; | |
548 | fail: | |
897ab3e0 | 549 | do_munmap(vma->vm_mm, from, len, NULL); |
0692dedc VK |
550 | return -EAGAIN; |
551 | } | |
552 | ||
553 | static int vmcore_remap_oldmem_pfn(struct vm_area_struct *vma, | |
554 | unsigned long from, unsigned long pfn, | |
555 | unsigned long size, pgprot_t prot) | |
556 | { | |
5039b170 | 557 | int ret, idx; |
cc5f2704 | 558 | |
0692dedc | 559 | /* |
5039b170 DH |
560 | * Check if a callback was registered to avoid looping over all |
561 | * pages without a reason. | |
0692dedc | 562 | */ |
5039b170 | 563 | idx = srcu_read_lock(&vmcore_cb_srcu); |
25bc5b0d | 564 | if (!list_empty(&vmcore_cb_list)) |
cc5f2704 | 565 | ret = remap_oldmem_pfn_checked(vma, from, pfn, size, prot); |
0692dedc | 566 | else |
cc5f2704 | 567 | ret = remap_oldmem_pfn_range(vma, from, pfn, size, prot); |
5039b170 | 568 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
cc5f2704 | 569 | return ret; |
0692dedc VK |
570 | } |
571 | ||
83086978 HD |
572 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) |
573 | { | |
574 | size_t size = vma->vm_end - vma->vm_start; | |
575 | u64 start, end, len, tsz; | |
576 | struct vmcore *m; | |
577 | ||
578 | start = (u64)vma->vm_pgoff << PAGE_SHIFT; | |
579 | end = start + size; | |
580 | ||
581 | if (size > vmcore_size || end > vmcore_size) | |
582 | return -EINVAL; | |
583 | ||
584 | if (vma->vm_flags & (VM_WRITE | VM_EXEC)) | |
585 | return -EPERM; | |
586 | ||
1c71222e | 587 | vm_flags_mod(vma, VM_MIXEDMAP, VM_MAYWRITE | VM_MAYEXEC); |
9cb21813 | 588 | vma->vm_ops = &vmcore_mmap_ops; |
83086978 HD |
589 | |
590 | len = 0; | |
591 | ||
592 | if (start < elfcorebuf_sz) { | |
593 | u64 pfn; | |
594 | ||
595 | tsz = min(elfcorebuf_sz - (size_t)start, size); | |
596 | pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT; | |
597 | if (remap_pfn_range(vma, vma->vm_start, pfn, tsz, | |
598 | vma->vm_page_prot)) | |
599 | return -EAGAIN; | |
600 | size -= tsz; | |
601 | start += tsz; | |
602 | len += tsz; | |
603 | ||
604 | if (size == 0) | |
605 | return 0; | |
606 | } | |
607 | ||
608 | if (start < elfcorebuf_sz + elfnotes_sz) { | |
609 | void *kaddr; | |
610 | ||
7efe48df RL |
611 | /* We add device dumps before other elf notes because the |
612 | * other elf notes may not fill the elf notes buffer | |
613 | * completely and we will end up with zero-filled data | |
614 | * between the elf notes and the device dumps. Tools will | |
615 | * then try to decode this zero-filled data as valid notes | |
616 | * and we don't want that. Hence, adding device dumps before | |
617 | * the other elf notes ensure that zero-filled data can be | |
618 | * avoided. This also ensures that the device dumps and | |
619 | * other elf notes can be properly mmaped at page aligned | |
620 | * address. | |
621 | */ | |
622 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
623 | /* Read device dumps */ | |
624 | if (start < elfcorebuf_sz + vmcoredd_orig_sz) { | |
625 | u64 start_off; | |
626 | ||
627 | tsz = min(elfcorebuf_sz + vmcoredd_orig_sz - | |
628 | (size_t)start, size); | |
629 | start_off = start - elfcorebuf_sz; | |
630 | if (vmcoredd_mmap_dumps(vma, vma->vm_start + len, | |
631 | start_off, tsz)) | |
632 | goto fail; | |
633 | ||
634 | size -= tsz; | |
635 | start += tsz; | |
636 | len += tsz; | |
637 | ||
638 | /* leave now if filled buffer already */ | |
639 | if (!size) | |
640 | return 0; | |
641 | } | |
642 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
643 | ||
644 | /* Read remaining elf notes */ | |
83086978 | 645 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size); |
7efe48df | 646 | kaddr = elfnotes_buf + start - elfcorebuf_sz - vmcoredd_orig_sz; |
83086978 | 647 | if (remap_vmalloc_range_partial(vma, vma->vm_start + len, |
bdebd6a2 | 648 | kaddr, 0, tsz)) |
83086978 | 649 | goto fail; |
7efe48df | 650 | |
83086978 HD |
651 | size -= tsz; |
652 | start += tsz; | |
653 | len += tsz; | |
654 | ||
655 | if (size == 0) | |
656 | return 0; | |
657 | } | |
658 | ||
659 | list_for_each_entry(m, &vmcore_list, list) { | |
660 | if (start < m->offset + m->size) { | |
661 | u64 paddr = 0; | |
662 | ||
0b50a2d8 DY |
663 | tsz = (size_t)min_t(unsigned long long, |
664 | m->offset + m->size - start, size); | |
83086978 | 665 | paddr = m->paddr + start - m->offset; |
0692dedc VK |
666 | if (vmcore_remap_oldmem_pfn(vma, vma->vm_start + len, |
667 | paddr >> PAGE_SHIFT, tsz, | |
668 | vma->vm_page_prot)) | |
83086978 HD |
669 | goto fail; |
670 | size -= tsz; | |
671 | start += tsz; | |
672 | len += tsz; | |
673 | ||
674 | if (size == 0) | |
675 | return 0; | |
676 | } | |
677 | } | |
678 | ||
679 | return 0; | |
680 | fail: | |
897ab3e0 | 681 | do_munmap(vma->vm_mm, vma->vm_start, len, NULL); |
83086978 HD |
682 | return -EAGAIN; |
683 | } | |
684 | #else | |
685 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) | |
686 | { | |
687 | return -ENOSYS; | |
688 | } | |
689 | #endif | |
690 | ||
97a32539 | 691 | static const struct proc_ops vmcore_proc_ops = { |
cc5f2704 | 692 | .proc_open = open_vmcore, |
4a22fd20 | 693 | .proc_read_iter = read_vmcore, |
97a32539 AD |
694 | .proc_lseek = default_llseek, |
695 | .proc_mmap = mmap_vmcore, | |
666bfddb VG |
696 | }; |
697 | ||
698 | static struct vmcore* __init get_new_element(void) | |
699 | { | |
2f6d3110 | 700 | return kzalloc(sizeof(struct vmcore), GFP_KERNEL); |
666bfddb VG |
701 | } |
702 | ||
44c752fe RL |
703 | static u64 get_vmcore_size(size_t elfsz, size_t elfnotesegsz, |
704 | struct list_head *vc_list) | |
666bfddb | 705 | { |
666bfddb | 706 | u64 size; |
591ff716 | 707 | struct vmcore *m; |
72658e9d | 708 | |
591ff716 HD |
709 | size = elfsz + elfnotesegsz; |
710 | list_for_each_entry(m, vc_list, list) { | |
711 | size += m->size; | |
72658e9d VG |
712 | } |
713 | return size; | |
714 | } | |
715 | ||
087350c9 HD |
716 | /** |
717 | * update_note_header_size_elf64 - update p_memsz member of each PT_NOTE entry | |
718 | * | |
719 | * @ehdr_ptr: ELF header | |
720 | * | |
721 | * This function updates p_memsz member of each PT_NOTE entry in the | |
722 | * program header table pointed to by @ehdr_ptr to real size of ELF | |
723 | * note segment. | |
724 | */ | |
725 | static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr) | |
666bfddb | 726 | { |
087350c9 HD |
727 | int i, rc=0; |
728 | Elf64_Phdr *phdr_ptr; | |
666bfddb | 729 | Elf64_Nhdr *nhdr_ptr; |
666bfddb | 730 | |
087350c9 | 731 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); |
666bfddb | 732 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
666bfddb | 733 | void *notes_section; |
666bfddb VG |
734 | u64 offset, max_sz, sz, real_sz = 0; |
735 | if (phdr_ptr->p_type != PT_NOTE) | |
736 | continue; | |
666bfddb VG |
737 | max_sz = phdr_ptr->p_memsz; |
738 | offset = phdr_ptr->p_offset; | |
739 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
740 | if (!notes_section) | |
741 | return -ENOMEM; | |
be8a8d06 | 742 | rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); |
666bfddb VG |
743 | if (rc < 0) { |
744 | kfree(notes_section); | |
745 | return rc; | |
746 | } | |
747 | nhdr_ptr = notes_section; | |
38dfac84 | 748 | while (nhdr_ptr->n_namesz != 0) { |
666bfddb | 749 | sz = sizeof(Elf64_Nhdr) + |
34b47764 WC |
750 | (((u64)nhdr_ptr->n_namesz + 3) & ~3) + |
751 | (((u64)nhdr_ptr->n_descsz + 3) & ~3); | |
38dfac84 GP |
752 | if ((real_sz + sz) > max_sz) { |
753 | pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n", | |
754 | nhdr_ptr->n_namesz, nhdr_ptr->n_descsz); | |
755 | break; | |
756 | } | |
666bfddb VG |
757 | real_sz += sz; |
758 | nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz); | |
759 | } | |
666bfddb | 760 | kfree(notes_section); |
087350c9 | 761 | phdr_ptr->p_memsz = real_sz; |
38dfac84 GP |
762 | if (real_sz == 0) { |
763 | pr_warn("Warning: Zero PT_NOTE entries found\n"); | |
38dfac84 | 764 | } |
666bfddb VG |
765 | } |
766 | ||
087350c9 HD |
767 | return 0; |
768 | } | |
769 | ||
770 | /** | |
771 | * get_note_number_and_size_elf64 - get the number of PT_NOTE program | |
772 | * headers and sum of real size of their ELF note segment headers and | |
773 | * data. | |
774 | * | |
775 | * @ehdr_ptr: ELF header | |
776 | * @nr_ptnote: buffer for the number of PT_NOTE program headers | |
777 | * @sz_ptnote: buffer for size of unique PT_NOTE program header | |
778 | * | |
779 | * This function is used to merge multiple PT_NOTE program headers | |
780 | * into a unique single one. The resulting unique entry will have | |
781 | * @sz_ptnote in its phdr->p_mem. | |
782 | * | |
783 | * It is assumed that program headers with PT_NOTE type pointed to by | |
784 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 | |
785 | * and each of PT_NOTE program headers has actual ELF note segment | |
786 | * size in its p_memsz member. | |
787 | */ | |
788 | static int __init get_note_number_and_size_elf64(const Elf64_Ehdr *ehdr_ptr, | |
789 | int *nr_ptnote, u64 *sz_ptnote) | |
790 | { | |
791 | int i; | |
792 | Elf64_Phdr *phdr_ptr; | |
793 | ||
794 | *nr_ptnote = *sz_ptnote = 0; | |
795 | ||
796 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); | |
797 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
798 | if (phdr_ptr->p_type != PT_NOTE) | |
799 | continue; | |
800 | *nr_ptnote += 1; | |
801 | *sz_ptnote += phdr_ptr->p_memsz; | |
802 | } | |
803 | ||
804 | return 0; | |
805 | } | |
806 | ||
807 | /** | |
808 | * copy_notes_elf64 - copy ELF note segments in a given buffer | |
809 | * | |
810 | * @ehdr_ptr: ELF header | |
811 | * @notes_buf: buffer into which ELF note segments are copied | |
812 | * | |
813 | * This function is used to copy ELF note segment in the 1st kernel | |
814 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that | |
815 | * size of the buffer @notes_buf is equal to or larger than sum of the | |
816 | * real ELF note segment headers and data. | |
817 | * | |
818 | * It is assumed that program headers with PT_NOTE type pointed to by | |
819 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 | |
820 | * and each of PT_NOTE program headers has actual ELF note segment | |
821 | * size in its p_memsz member. | |
822 | */ | |
823 | static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf) | |
824 | { | |
825 | int i, rc=0; | |
826 | Elf64_Phdr *phdr_ptr; | |
827 | ||
828 | phdr_ptr = (Elf64_Phdr*)(ehdr_ptr + 1); | |
829 | ||
830 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
831 | u64 offset; | |
832 | if (phdr_ptr->p_type != PT_NOTE) | |
833 | continue; | |
834 | offset = phdr_ptr->p_offset; | |
be8a8d06 MH |
835 | rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, |
836 | &offset); | |
087350c9 HD |
837 | if (rc < 0) |
838 | return rc; | |
839 | notes_buf += phdr_ptr->p_memsz; | |
840 | } | |
841 | ||
842 | return 0; | |
843 | } | |
844 | ||
845 | /* Merges all the PT_NOTE headers into one. */ | |
846 | static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, | |
847 | char **notes_buf, size_t *notes_sz) | |
848 | { | |
849 | int i, nr_ptnote=0, rc=0; | |
850 | char *tmp; | |
851 | Elf64_Ehdr *ehdr_ptr; | |
852 | Elf64_Phdr phdr; | |
853 | u64 phdr_sz = 0, note_off; | |
854 | ||
855 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
856 | ||
857 | rc = update_note_header_size_elf64(ehdr_ptr); | |
858 | if (rc < 0) | |
859 | return rc; | |
860 | ||
861 | rc = get_note_number_and_size_elf64(ehdr_ptr, &nr_ptnote, &phdr_sz); | |
862 | if (rc < 0) | |
863 | return rc; | |
864 | ||
865 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); | |
2724273e | 866 | *notes_buf = vmcore_alloc_buf(*notes_sz); |
087350c9 HD |
867 | if (!*notes_buf) |
868 | return -ENOMEM; | |
869 | ||
870 | rc = copy_notes_elf64(ehdr_ptr, *notes_buf); | |
871 | if (rc < 0) | |
872 | return rc; | |
873 | ||
666bfddb VG |
874 | /* Prepare merged PT_NOTE program header. */ |
875 | phdr.p_type = PT_NOTE; | |
876 | phdr.p_flags = 0; | |
877 | note_off = sizeof(Elf64_Ehdr) + | |
878 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr); | |
087350c9 | 879 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
666bfddb VG |
880 | phdr.p_vaddr = phdr.p_paddr = 0; |
881 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
60592fb6 | 882 | phdr.p_align = 4; |
666bfddb VG |
883 | |
884 | /* Add merged PT_NOTE program header*/ | |
885 | tmp = elfptr + sizeof(Elf64_Ehdr); | |
886 | memcpy(tmp, &phdr, sizeof(phdr)); | |
887 | tmp += sizeof(phdr); | |
888 | ||
889 | /* Remove unwanted PT_NOTE program headers. */ | |
890 | i = (nr_ptnote - 1) * sizeof(Elf64_Phdr); | |
891 | *elfsz = *elfsz - i; | |
892 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr))); | |
f2bdacdd HD |
893 | memset(elfptr + *elfsz, 0, i); |
894 | *elfsz = roundup(*elfsz, PAGE_SIZE); | |
666bfddb VG |
895 | |
896 | /* Modify e_phnum to reflect merged headers. */ | |
897 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
898 | ||
7efe48df RL |
899 | /* Store the size of all notes. We need this to update the note |
900 | * header when the device dumps will be added. | |
901 | */ | |
902 | elfnotes_orig_sz = phdr.p_memsz; | |
903 | ||
666bfddb VG |
904 | return 0; |
905 | } | |
906 | ||
087350c9 HD |
907 | /** |
908 | * update_note_header_size_elf32 - update p_memsz member of each PT_NOTE entry | |
909 | * | |
910 | * @ehdr_ptr: ELF header | |
911 | * | |
912 | * This function updates p_memsz member of each PT_NOTE entry in the | |
913 | * program header table pointed to by @ehdr_ptr to real size of ELF | |
914 | * note segment. | |
915 | */ | |
916 | static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr) | |
72658e9d | 917 | { |
087350c9 HD |
918 | int i, rc=0; |
919 | Elf32_Phdr *phdr_ptr; | |
72658e9d | 920 | Elf32_Nhdr *nhdr_ptr; |
72658e9d | 921 | |
087350c9 | 922 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); |
72658e9d | 923 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
72658e9d | 924 | void *notes_section; |
72658e9d VG |
925 | u64 offset, max_sz, sz, real_sz = 0; |
926 | if (phdr_ptr->p_type != PT_NOTE) | |
927 | continue; | |
72658e9d VG |
928 | max_sz = phdr_ptr->p_memsz; |
929 | offset = phdr_ptr->p_offset; | |
930 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
931 | if (!notes_section) | |
932 | return -ENOMEM; | |
be8a8d06 | 933 | rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); |
72658e9d VG |
934 | if (rc < 0) { |
935 | kfree(notes_section); | |
936 | return rc; | |
937 | } | |
938 | nhdr_ptr = notes_section; | |
38dfac84 | 939 | while (nhdr_ptr->n_namesz != 0) { |
72658e9d | 940 | sz = sizeof(Elf32_Nhdr) + |
34b47764 WC |
941 | (((u64)nhdr_ptr->n_namesz + 3) & ~3) + |
942 | (((u64)nhdr_ptr->n_descsz + 3) & ~3); | |
38dfac84 GP |
943 | if ((real_sz + sz) > max_sz) { |
944 | pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n", | |
945 | nhdr_ptr->n_namesz, nhdr_ptr->n_descsz); | |
946 | break; | |
947 | } | |
72658e9d VG |
948 | real_sz += sz; |
949 | nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz); | |
950 | } | |
72658e9d | 951 | kfree(notes_section); |
087350c9 | 952 | phdr_ptr->p_memsz = real_sz; |
38dfac84 GP |
953 | if (real_sz == 0) { |
954 | pr_warn("Warning: Zero PT_NOTE entries found\n"); | |
38dfac84 | 955 | } |
087350c9 HD |
956 | } |
957 | ||
958 | return 0; | |
959 | } | |
960 | ||
961 | /** | |
962 | * get_note_number_and_size_elf32 - get the number of PT_NOTE program | |
963 | * headers and sum of real size of their ELF note segment headers and | |
964 | * data. | |
965 | * | |
966 | * @ehdr_ptr: ELF header | |
967 | * @nr_ptnote: buffer for the number of PT_NOTE program headers | |
968 | * @sz_ptnote: buffer for size of unique PT_NOTE program header | |
969 | * | |
970 | * This function is used to merge multiple PT_NOTE program headers | |
971 | * into a unique single one. The resulting unique entry will have | |
972 | * @sz_ptnote in its phdr->p_mem. | |
973 | * | |
974 | * It is assumed that program headers with PT_NOTE type pointed to by | |
975 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 | |
976 | * and each of PT_NOTE program headers has actual ELF note segment | |
977 | * size in its p_memsz member. | |
978 | */ | |
979 | static int __init get_note_number_and_size_elf32(const Elf32_Ehdr *ehdr_ptr, | |
980 | int *nr_ptnote, u64 *sz_ptnote) | |
981 | { | |
982 | int i; | |
983 | Elf32_Phdr *phdr_ptr; | |
984 | ||
985 | *nr_ptnote = *sz_ptnote = 0; | |
986 | ||
987 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); | |
988 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
989 | if (phdr_ptr->p_type != PT_NOTE) | |
990 | continue; | |
991 | *nr_ptnote += 1; | |
992 | *sz_ptnote += phdr_ptr->p_memsz; | |
72658e9d VG |
993 | } |
994 | ||
087350c9 HD |
995 | return 0; |
996 | } | |
997 | ||
998 | /** | |
999 | * copy_notes_elf32 - copy ELF note segments in a given buffer | |
1000 | * | |
1001 | * @ehdr_ptr: ELF header | |
1002 | * @notes_buf: buffer into which ELF note segments are copied | |
1003 | * | |
1004 | * This function is used to copy ELF note segment in the 1st kernel | |
1005 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that | |
1006 | * size of the buffer @notes_buf is equal to or larger than sum of the | |
1007 | * real ELF note segment headers and data. | |
1008 | * | |
1009 | * It is assumed that program headers with PT_NOTE type pointed to by | |
1010 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 | |
1011 | * and each of PT_NOTE program headers has actual ELF note segment | |
1012 | * size in its p_memsz member. | |
1013 | */ | |
1014 | static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf) | |
1015 | { | |
1016 | int i, rc=0; | |
1017 | Elf32_Phdr *phdr_ptr; | |
1018 | ||
1019 | phdr_ptr = (Elf32_Phdr*)(ehdr_ptr + 1); | |
1020 | ||
1021 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
1022 | u64 offset; | |
1023 | if (phdr_ptr->p_type != PT_NOTE) | |
1024 | continue; | |
1025 | offset = phdr_ptr->p_offset; | |
be8a8d06 MH |
1026 | rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, |
1027 | &offset); | |
087350c9 HD |
1028 | if (rc < 0) |
1029 | return rc; | |
1030 | notes_buf += phdr_ptr->p_memsz; | |
1031 | } | |
1032 | ||
1033 | return 0; | |
1034 | } | |
1035 | ||
1036 | /* Merges all the PT_NOTE headers into one. */ | |
1037 | static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, | |
1038 | char **notes_buf, size_t *notes_sz) | |
1039 | { | |
1040 | int i, nr_ptnote=0, rc=0; | |
1041 | char *tmp; | |
1042 | Elf32_Ehdr *ehdr_ptr; | |
1043 | Elf32_Phdr phdr; | |
1044 | u64 phdr_sz = 0, note_off; | |
1045 | ||
1046 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
1047 | ||
1048 | rc = update_note_header_size_elf32(ehdr_ptr); | |
1049 | if (rc < 0) | |
1050 | return rc; | |
1051 | ||
1052 | rc = get_note_number_and_size_elf32(ehdr_ptr, &nr_ptnote, &phdr_sz); | |
1053 | if (rc < 0) | |
1054 | return rc; | |
1055 | ||
1056 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); | |
2724273e | 1057 | *notes_buf = vmcore_alloc_buf(*notes_sz); |
087350c9 HD |
1058 | if (!*notes_buf) |
1059 | return -ENOMEM; | |
1060 | ||
1061 | rc = copy_notes_elf32(ehdr_ptr, *notes_buf); | |
1062 | if (rc < 0) | |
1063 | return rc; | |
1064 | ||
72658e9d VG |
1065 | /* Prepare merged PT_NOTE program header. */ |
1066 | phdr.p_type = PT_NOTE; | |
1067 | phdr.p_flags = 0; | |
1068 | note_off = sizeof(Elf32_Ehdr) + | |
1069 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr); | |
087350c9 | 1070 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
72658e9d VG |
1071 | phdr.p_vaddr = phdr.p_paddr = 0; |
1072 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
60592fb6 | 1073 | phdr.p_align = 4; |
72658e9d VG |
1074 | |
1075 | /* Add merged PT_NOTE program header*/ | |
1076 | tmp = elfptr + sizeof(Elf32_Ehdr); | |
1077 | memcpy(tmp, &phdr, sizeof(phdr)); | |
1078 | tmp += sizeof(phdr); | |
1079 | ||
1080 | /* Remove unwanted PT_NOTE program headers. */ | |
1081 | i = (nr_ptnote - 1) * sizeof(Elf32_Phdr); | |
1082 | *elfsz = *elfsz - i; | |
1083 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr))); | |
f2bdacdd HD |
1084 | memset(elfptr + *elfsz, 0, i); |
1085 | *elfsz = roundup(*elfsz, PAGE_SIZE); | |
72658e9d VG |
1086 | |
1087 | /* Modify e_phnum to reflect merged headers. */ | |
1088 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
1089 | ||
7efe48df RL |
1090 | /* Store the size of all notes. We need this to update the note |
1091 | * header when the device dumps will be added. | |
1092 | */ | |
1093 | elfnotes_orig_sz = phdr.p_memsz; | |
1094 | ||
72658e9d VG |
1095 | return 0; |
1096 | } | |
1097 | ||
666bfddb VG |
1098 | /* Add memory chunks represented by program headers to vmcore list. Also update |
1099 | * the new offset fields of exported program headers. */ | |
1100 | static int __init process_ptload_program_headers_elf64(char *elfptr, | |
1101 | size_t elfsz, | |
087350c9 | 1102 | size_t elfnotes_sz, |
666bfddb VG |
1103 | struct list_head *vc_list) |
1104 | { | |
1105 | int i; | |
1106 | Elf64_Ehdr *ehdr_ptr; | |
1107 | Elf64_Phdr *phdr_ptr; | |
1108 | loff_t vmcore_off; | |
1109 | struct vmcore *new; | |
1110 | ||
1111 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
1112 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ | |
1113 | ||
70e79866 | 1114 | /* Skip ELF header, program headers and ELF note segment. */ |
087350c9 | 1115 | vmcore_off = elfsz + elfnotes_sz; |
666bfddb VG |
1116 | |
1117 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
7f614cd1 HD |
1118 | u64 paddr, start, end, size; |
1119 | ||
666bfddb VG |
1120 | if (phdr_ptr->p_type != PT_LOAD) |
1121 | continue; | |
1122 | ||
7f614cd1 HD |
1123 | paddr = phdr_ptr->p_offset; |
1124 | start = rounddown(paddr, PAGE_SIZE); | |
1125 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); | |
1126 | size = end - start; | |
1127 | ||
666bfddb VG |
1128 | /* Add this contiguous chunk of memory to vmcore list.*/ |
1129 | new = get_new_element(); | |
1130 | if (!new) | |
1131 | return -ENOMEM; | |
7f614cd1 HD |
1132 | new->paddr = start; |
1133 | new->size = size; | |
666bfddb VG |
1134 | list_add_tail(&new->list, vc_list); |
1135 | ||
1136 | /* Update the program header offset. */ | |
7f614cd1 HD |
1137 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
1138 | vmcore_off = vmcore_off + size; | |
666bfddb VG |
1139 | } |
1140 | return 0; | |
1141 | } | |
1142 | ||
72658e9d VG |
1143 | static int __init process_ptload_program_headers_elf32(char *elfptr, |
1144 | size_t elfsz, | |
087350c9 | 1145 | size_t elfnotes_sz, |
72658e9d VG |
1146 | struct list_head *vc_list) |
1147 | { | |
1148 | int i; | |
1149 | Elf32_Ehdr *ehdr_ptr; | |
1150 | Elf32_Phdr *phdr_ptr; | |
1151 | loff_t vmcore_off; | |
1152 | struct vmcore *new; | |
1153 | ||
1154 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
1155 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ | |
1156 | ||
70e79866 | 1157 | /* Skip ELF header, program headers and ELF note segment. */ |
087350c9 | 1158 | vmcore_off = elfsz + elfnotes_sz; |
72658e9d VG |
1159 | |
1160 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
7f614cd1 HD |
1161 | u64 paddr, start, end, size; |
1162 | ||
72658e9d VG |
1163 | if (phdr_ptr->p_type != PT_LOAD) |
1164 | continue; | |
1165 | ||
7f614cd1 HD |
1166 | paddr = phdr_ptr->p_offset; |
1167 | start = rounddown(paddr, PAGE_SIZE); | |
1168 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); | |
1169 | size = end - start; | |
1170 | ||
72658e9d VG |
1171 | /* Add this contiguous chunk of memory to vmcore list.*/ |
1172 | new = get_new_element(); | |
1173 | if (!new) | |
1174 | return -ENOMEM; | |
7f614cd1 HD |
1175 | new->paddr = start; |
1176 | new->size = size; | |
72658e9d VG |
1177 | list_add_tail(&new->list, vc_list); |
1178 | ||
1179 | /* Update the program header offset */ | |
7f614cd1 HD |
1180 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
1181 | vmcore_off = vmcore_off + size; | |
72658e9d VG |
1182 | } |
1183 | return 0; | |
1184 | } | |
1185 | ||
666bfddb | 1186 | /* Sets offset fields of vmcore elements. */ |
7efe48df RL |
1187 | static void set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz, |
1188 | struct list_head *vc_list) | |
666bfddb VG |
1189 | { |
1190 | loff_t vmcore_off; | |
666bfddb VG |
1191 | struct vmcore *m; |
1192 | ||
70e79866 | 1193 | /* Skip ELF header, program headers and ELF note segment. */ |
087350c9 | 1194 | vmcore_off = elfsz + elfnotes_sz; |
666bfddb VG |
1195 | |
1196 | list_for_each_entry(m, vc_list, list) { | |
1197 | m->offset = vmcore_off; | |
1198 | vmcore_off += m->size; | |
1199 | } | |
1200 | } | |
1201 | ||
f2bdacdd | 1202 | static void free_elfcorebuf(void) |
72658e9d | 1203 | { |
f2bdacdd HD |
1204 | free_pages((unsigned long)elfcorebuf, get_order(elfcorebuf_sz_orig)); |
1205 | elfcorebuf = NULL; | |
087350c9 HD |
1206 | vfree(elfnotes_buf); |
1207 | elfnotes_buf = NULL; | |
72658e9d VG |
1208 | } |
1209 | ||
666bfddb VG |
1210 | static int __init parse_crash_elf64_headers(void) |
1211 | { | |
1212 | int rc=0; | |
1213 | Elf64_Ehdr ehdr; | |
1214 | u64 addr; | |
1215 | ||
1216 | addr = elfcorehdr_addr; | |
1217 | ||
70e79866 | 1218 | /* Read ELF header */ |
be8a8d06 | 1219 | rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf64_Ehdr), &addr); |
666bfddb VG |
1220 | if (rc < 0) |
1221 | return rc; | |
1222 | ||
1223 | /* Do some basic Verification. */ | |
1224 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
1225 | (ehdr.e_type != ET_CORE) || | |
9833c394 | 1226 | !vmcore_elf64_check_arch(&ehdr) || |
666bfddb VG |
1227 | ehdr.e_ident[EI_CLASS] != ELFCLASS64 || |
1228 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
1229 | ehdr.e_version != EV_CURRENT || | |
1230 | ehdr.e_ehsize != sizeof(Elf64_Ehdr) || | |
1231 | ehdr.e_phentsize != sizeof(Elf64_Phdr) || | |
1232 | ehdr.e_phnum == 0) { | |
87ebdc00 | 1233 | pr_warn("Warning: Core image elf header is not sane\n"); |
666bfddb VG |
1234 | return -EINVAL; |
1235 | } | |
1236 | ||
1237 | /* Read in all elf headers. */ | |
f2bdacdd HD |
1238 | elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) + |
1239 | ehdr.e_phnum * sizeof(Elf64_Phdr); | |
1240 | elfcorebuf_sz = elfcorebuf_sz_orig; | |
1241 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, | |
1242 | get_order(elfcorebuf_sz_orig)); | |
666bfddb VG |
1243 | if (!elfcorebuf) |
1244 | return -ENOMEM; | |
1245 | addr = elfcorehdr_addr; | |
be8a8d06 | 1246 | rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); |
f2bdacdd HD |
1247 | if (rc < 0) |
1248 | goto fail; | |
666bfddb VG |
1249 | |
1250 | /* Merge all PT_NOTE headers into one. */ | |
087350c9 HD |
1251 | rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, |
1252 | &elfnotes_buf, &elfnotes_sz); | |
f2bdacdd HD |
1253 | if (rc) |
1254 | goto fail; | |
666bfddb | 1255 | rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, |
087350c9 | 1256 | elfnotes_sz, &vmcore_list); |
f2bdacdd HD |
1257 | if (rc) |
1258 | goto fail; | |
087350c9 | 1259 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
666bfddb | 1260 | return 0; |
f2bdacdd HD |
1261 | fail: |
1262 | free_elfcorebuf(); | |
1263 | return rc; | |
666bfddb VG |
1264 | } |
1265 | ||
72658e9d VG |
1266 | static int __init parse_crash_elf32_headers(void) |
1267 | { | |
1268 | int rc=0; | |
1269 | Elf32_Ehdr ehdr; | |
1270 | u64 addr; | |
1271 | ||
1272 | addr = elfcorehdr_addr; | |
1273 | ||
70e79866 | 1274 | /* Read ELF header */ |
be8a8d06 | 1275 | rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf32_Ehdr), &addr); |
72658e9d VG |
1276 | if (rc < 0) |
1277 | return rc; | |
1278 | ||
1279 | /* Do some basic Verification. */ | |
1280 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
1281 | (ehdr.e_type != ET_CORE) || | |
e55d5312 | 1282 | !vmcore_elf32_check_arch(&ehdr) || |
72658e9d VG |
1283 | ehdr.e_ident[EI_CLASS] != ELFCLASS32|| |
1284 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
1285 | ehdr.e_version != EV_CURRENT || | |
1286 | ehdr.e_ehsize != sizeof(Elf32_Ehdr) || | |
1287 | ehdr.e_phentsize != sizeof(Elf32_Phdr) || | |
1288 | ehdr.e_phnum == 0) { | |
87ebdc00 | 1289 | pr_warn("Warning: Core image elf header is not sane\n"); |
72658e9d VG |
1290 | return -EINVAL; |
1291 | } | |
1292 | ||
1293 | /* Read in all elf headers. */ | |
f2bdacdd HD |
1294 | elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); |
1295 | elfcorebuf_sz = elfcorebuf_sz_orig; | |
1296 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, | |
1297 | get_order(elfcorebuf_sz_orig)); | |
72658e9d VG |
1298 | if (!elfcorebuf) |
1299 | return -ENOMEM; | |
1300 | addr = elfcorehdr_addr; | |
be8a8d06 | 1301 | rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); |
f2bdacdd HD |
1302 | if (rc < 0) |
1303 | goto fail; | |
72658e9d VG |
1304 | |
1305 | /* Merge all PT_NOTE headers into one. */ | |
087350c9 HD |
1306 | rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, |
1307 | &elfnotes_buf, &elfnotes_sz); | |
f2bdacdd HD |
1308 | if (rc) |
1309 | goto fail; | |
72658e9d | 1310 | rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, |
087350c9 | 1311 | elfnotes_sz, &vmcore_list); |
f2bdacdd HD |
1312 | if (rc) |
1313 | goto fail; | |
087350c9 | 1314 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
72658e9d | 1315 | return 0; |
f2bdacdd HD |
1316 | fail: |
1317 | free_elfcorebuf(); | |
1318 | return rc; | |
72658e9d VG |
1319 | } |
1320 | ||
666bfddb VG |
1321 | static int __init parse_crash_elf_headers(void) |
1322 | { | |
1323 | unsigned char e_ident[EI_NIDENT]; | |
1324 | u64 addr; | |
1325 | int rc=0; | |
1326 | ||
1327 | addr = elfcorehdr_addr; | |
be8a8d06 | 1328 | rc = elfcorehdr_read(e_ident, EI_NIDENT, &addr); |
666bfddb VG |
1329 | if (rc < 0) |
1330 | return rc; | |
1331 | if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { | |
87ebdc00 | 1332 | pr_warn("Warning: Core image elf header not found\n"); |
666bfddb VG |
1333 | return -EINVAL; |
1334 | } | |
1335 | ||
1336 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
1337 | rc = parse_crash_elf64_headers(); | |
1338 | if (rc) | |
1339 | return rc; | |
72658e9d VG |
1340 | } else if (e_ident[EI_CLASS] == ELFCLASS32) { |
1341 | rc = parse_crash_elf32_headers(); | |
1342 | if (rc) | |
1343 | return rc; | |
666bfddb | 1344 | } else { |
87ebdc00 | 1345 | pr_warn("Warning: Core image elf header is not sane\n"); |
666bfddb VG |
1346 | return -EINVAL; |
1347 | } | |
591ff716 HD |
1348 | |
1349 | /* Determine vmcore size. */ | |
1350 | vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, | |
1351 | &vmcore_list); | |
1352 | ||
666bfddb VG |
1353 | return 0; |
1354 | } | |
1355 | ||
2724273e RL |
1356 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
1357 | /** | |
1358 | * vmcoredd_write_header - Write vmcore device dump header at the | |
1359 | * beginning of the dump's buffer. | |
1360 | * @buf: Output buffer where the note is written | |
1361 | * @data: Dump info | |
1362 | * @size: Size of the dump | |
1363 | * | |
1364 | * Fills beginning of the dump's buffer with vmcore device dump header. | |
1365 | */ | |
1366 | static void vmcoredd_write_header(void *buf, struct vmcoredd_data *data, | |
1367 | u32 size) | |
1368 | { | |
1369 | struct vmcoredd_header *vdd_hdr = (struct vmcoredd_header *)buf; | |
1370 | ||
1371 | vdd_hdr->n_namesz = sizeof(vdd_hdr->name); | |
1372 | vdd_hdr->n_descsz = size + sizeof(vdd_hdr->dump_name); | |
1373 | vdd_hdr->n_type = NT_VMCOREDD; | |
1374 | ||
ad5f0eb5 JS |
1375 | strscpy_pad(vdd_hdr->name, VMCOREDD_NOTE_NAME); |
1376 | strscpy_pad(vdd_hdr->dump_name, data->dump_name); | |
2724273e RL |
1377 | } |
1378 | ||
7efe48df | 1379 | /** |
70e79866 | 1380 | * vmcoredd_update_program_headers - Update all ELF program headers |
7efe48df RL |
1381 | * @elfptr: Pointer to elf header |
1382 | * @elfnotesz: Size of elf notes aligned to page size | |
1383 | * @vmcoreddsz: Size of device dumps to be added to elf note header | |
1384 | * | |
70e79866 | 1385 | * Determine type of ELF header (Elf64 or Elf32) and update the elf note size. |
7efe48df RL |
1386 | * Also update the offsets of all the program headers after the elf note header. |
1387 | */ | |
1388 | static void vmcoredd_update_program_headers(char *elfptr, size_t elfnotesz, | |
1389 | size_t vmcoreddsz) | |
1390 | { | |
1391 | unsigned char *e_ident = (unsigned char *)elfptr; | |
1392 | u64 start, end, size; | |
1393 | loff_t vmcore_off; | |
1394 | u32 i; | |
1395 | ||
1396 | vmcore_off = elfcorebuf_sz + elfnotesz; | |
1397 | ||
1398 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
1399 | Elf64_Ehdr *ehdr = (Elf64_Ehdr *)elfptr; | |
1400 | Elf64_Phdr *phdr = (Elf64_Phdr *)(elfptr + sizeof(Elf64_Ehdr)); | |
1401 | ||
1402 | /* Update all program headers */ | |
1403 | for (i = 0; i < ehdr->e_phnum; i++, phdr++) { | |
1404 | if (phdr->p_type == PT_NOTE) { | |
1405 | /* Update note size */ | |
1406 | phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz; | |
1407 | phdr->p_filesz = phdr->p_memsz; | |
1408 | continue; | |
1409 | } | |
1410 | ||
1411 | start = rounddown(phdr->p_offset, PAGE_SIZE); | |
1412 | end = roundup(phdr->p_offset + phdr->p_memsz, | |
1413 | PAGE_SIZE); | |
1414 | size = end - start; | |
1415 | phdr->p_offset = vmcore_off + (phdr->p_offset - start); | |
1416 | vmcore_off += size; | |
1417 | } | |
1418 | } else { | |
1419 | Elf32_Ehdr *ehdr = (Elf32_Ehdr *)elfptr; | |
1420 | Elf32_Phdr *phdr = (Elf32_Phdr *)(elfptr + sizeof(Elf32_Ehdr)); | |
1421 | ||
1422 | /* Update all program headers */ | |
1423 | for (i = 0; i < ehdr->e_phnum; i++, phdr++) { | |
1424 | if (phdr->p_type == PT_NOTE) { | |
1425 | /* Update note size */ | |
1426 | phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz; | |
1427 | phdr->p_filesz = phdr->p_memsz; | |
1428 | continue; | |
1429 | } | |
1430 | ||
1431 | start = rounddown(phdr->p_offset, PAGE_SIZE); | |
1432 | end = roundup(phdr->p_offset + phdr->p_memsz, | |
1433 | PAGE_SIZE); | |
1434 | size = end - start; | |
1435 | phdr->p_offset = vmcore_off + (phdr->p_offset - start); | |
1436 | vmcore_off += size; | |
1437 | } | |
1438 | } | |
1439 | } | |
1440 | ||
1441 | /** | |
1442 | * vmcoredd_update_size - Update the total size of the device dumps and update | |
70e79866 | 1443 | * ELF header |
7efe48df RL |
1444 | * @dump_size: Size of the current device dump to be added to total size |
1445 | * | |
70e79866 | 1446 | * Update the total size of all the device dumps and update the ELF program |
7efe48df RL |
1447 | * headers. Calculate the new offsets for the vmcore list and update the |
1448 | * total vmcore size. | |
1449 | */ | |
1450 | static void vmcoredd_update_size(size_t dump_size) | |
1451 | { | |
1452 | vmcoredd_orig_sz += dump_size; | |
1453 | elfnotes_sz = roundup(elfnotes_orig_sz, PAGE_SIZE) + vmcoredd_orig_sz; | |
1454 | vmcoredd_update_program_headers(elfcorebuf, elfnotes_sz, | |
1455 | vmcoredd_orig_sz); | |
1456 | ||
1457 | /* Update vmcore list offsets */ | |
1458 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); | |
1459 | ||
1460 | vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, | |
1461 | &vmcore_list); | |
1462 | proc_vmcore->size = vmcore_size; | |
1463 | } | |
1464 | ||
2724273e RL |
1465 | /** |
1466 | * vmcore_add_device_dump - Add a buffer containing device dump to vmcore | |
1467 | * @data: dump info. | |
1468 | * | |
1469 | * Allocate a buffer and invoke the calling driver's dump collect routine. | |
70e79866 | 1470 | * Write ELF note at the beginning of the buffer to indicate vmcore device |
2724273e RL |
1471 | * dump and add the dump to global list. |
1472 | */ | |
1473 | int vmcore_add_device_dump(struct vmcoredd_data *data) | |
1474 | { | |
1475 | struct vmcoredd_node *dump; | |
1476 | void *buf = NULL; | |
1477 | size_t data_size; | |
1478 | int ret; | |
1479 | ||
c6c40533 KS |
1480 | if (vmcoredd_disabled) { |
1481 | pr_err_once("Device dump is disabled\n"); | |
1482 | return -EINVAL; | |
1483 | } | |
1484 | ||
2724273e RL |
1485 | if (!data || !strlen(data->dump_name) || |
1486 | !data->vmcoredd_callback || !data->size) | |
1487 | return -EINVAL; | |
1488 | ||
1489 | dump = vzalloc(sizeof(*dump)); | |
1490 | if (!dump) { | |
1491 | ret = -ENOMEM; | |
1492 | goto out_err; | |
1493 | } | |
1494 | ||
1495 | /* Keep size of the buffer page aligned so that it can be mmaped */ | |
1496 | data_size = roundup(sizeof(struct vmcoredd_header) + data->size, | |
1497 | PAGE_SIZE); | |
1498 | ||
1499 | /* Allocate buffer for driver's to write their dumps */ | |
1500 | buf = vmcore_alloc_buf(data_size); | |
1501 | if (!buf) { | |
1502 | ret = -ENOMEM; | |
1503 | goto out_err; | |
1504 | } | |
1505 | ||
1506 | vmcoredd_write_header(buf, data, data_size - | |
1507 | sizeof(struct vmcoredd_header)); | |
1508 | ||
1509 | /* Invoke the driver's dump collection routing */ | |
1510 | ret = data->vmcoredd_callback(data, buf + | |
1511 | sizeof(struct vmcoredd_header)); | |
1512 | if (ret) | |
1513 | goto out_err; | |
1514 | ||
1515 | dump->buf = buf; | |
1516 | dump->size = data_size; | |
1517 | ||
1518 | /* Add the dump to driver sysfs list */ | |
1519 | mutex_lock(&vmcoredd_mutex); | |
1520 | list_add_tail(&dump->list, &vmcoredd_list); | |
1521 | mutex_unlock(&vmcoredd_mutex); | |
1522 | ||
7efe48df | 1523 | vmcoredd_update_size(data_size); |
2724273e RL |
1524 | return 0; |
1525 | ||
1526 | out_err: | |
fb9bf048 YL |
1527 | vfree(buf); |
1528 | vfree(dump); | |
2724273e RL |
1529 | |
1530 | return ret; | |
1531 | } | |
1532 | EXPORT_SYMBOL(vmcore_add_device_dump); | |
1533 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
1534 | ||
1535 | /* Free all dumps in vmcore device dump list */ | |
1536 | static void vmcore_free_device_dumps(void) | |
1537 | { | |
1538 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
1539 | mutex_lock(&vmcoredd_mutex); | |
1540 | while (!list_empty(&vmcoredd_list)) { | |
1541 | struct vmcoredd_node *dump; | |
1542 | ||
1543 | dump = list_first_entry(&vmcoredd_list, struct vmcoredd_node, | |
1544 | list); | |
1545 | list_del(&dump->list); | |
1546 | vfree(dump->buf); | |
1547 | vfree(dump); | |
1548 | } | |
1549 | mutex_unlock(&vmcoredd_mutex); | |
1550 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
1551 | } | |
1552 | ||
666bfddb VG |
1553 | /* Init function for vmcore module. */ |
1554 | static int __init vmcore_init(void) | |
1555 | { | |
1556 | int rc = 0; | |
1557 | ||
be8a8d06 MH |
1558 | /* Allow architectures to allocate ELF header in 2nd kernel */ |
1559 | rc = elfcorehdr_alloc(&elfcorehdr_addr, &elfcorehdr_size); | |
1560 | if (rc) | |
1561 | return rc; | |
1562 | /* | |
1563 | * If elfcorehdr= has been passed in cmdline or created in 2nd kernel, | |
1564 | * then capture the dump. | |
1565 | */ | |
85a0ee34 | 1566 | if (!(is_vmcore_usable())) |
666bfddb VG |
1567 | return rc; |
1568 | rc = parse_crash_elf_headers(); | |
1569 | if (rc) { | |
12b9d301 | 1570 | elfcorehdr_free(elfcorehdr_addr); |
87ebdc00 | 1571 | pr_warn("Kdump: vmcore not initialized\n"); |
666bfddb VG |
1572 | return rc; |
1573 | } | |
be8a8d06 MH |
1574 | elfcorehdr_free(elfcorehdr_addr); |
1575 | elfcorehdr_addr = ELFCORE_ADDR_ERR; | |
666bfddb | 1576 | |
97a32539 | 1577 | proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &vmcore_proc_ops); |
666bfddb VG |
1578 | if (proc_vmcore) |
1579 | proc_vmcore->size = vmcore_size; | |
1580 | return 0; | |
1581 | } | |
abaf3787 | 1582 | fs_initcall(vmcore_init); |
16257393 MS |
1583 | |
1584 | /* Cleanup function for vmcore module. */ | |
1585 | void vmcore_cleanup(void) | |
1586 | { | |
16257393 | 1587 | if (proc_vmcore) { |
a8ca16ea | 1588 | proc_remove(proc_vmcore); |
16257393 MS |
1589 | proc_vmcore = NULL; |
1590 | } | |
1591 | ||
1592 | /* clear the vmcore list. */ | |
593bc695 | 1593 | while (!list_empty(&vmcore_list)) { |
16257393 MS |
1594 | struct vmcore *m; |
1595 | ||
593bc695 | 1596 | m = list_first_entry(&vmcore_list, struct vmcore, list); |
16257393 MS |
1597 | list_del(&m->list); |
1598 | kfree(m); | |
1599 | } | |
f2bdacdd | 1600 | free_elfcorebuf(); |
2724273e RL |
1601 | |
1602 | /* clear vmcore device dump list */ | |
1603 | vmcore_free_device_dumps(); | |
16257393 | 1604 | } |