Commit | Line | Data |
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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> |
7c0f6ba6 | 28 | #include <linux/uaccess.h> |
5d8de293 | 29 | #include <linux/uio.h> |
e9d1d2bb | 30 | #include <linux/cc_platform.h> |
666bfddb | 31 | #include <asm/io.h> |
2f96b8c1 | 32 | #include "internal.h" |
666bfddb VG |
33 | |
34 | /* List representing chunks of contiguous memory areas and their offsets in | |
35 | * vmcore file. | |
36 | */ | |
37 | static LIST_HEAD(vmcore_list); | |
38 | ||
39 | /* Stores the pointer to the buffer containing kernel elf core headers. */ | |
40 | static char *elfcorebuf; | |
41 | static size_t elfcorebuf_sz; | |
f2bdacdd | 42 | static size_t elfcorebuf_sz_orig; |
666bfddb | 43 | |
087350c9 HD |
44 | static char *elfnotes_buf; |
45 | static size_t elfnotes_sz; | |
7efe48df RL |
46 | /* Size of all notes minus the device dump notes */ |
47 | static size_t elfnotes_orig_sz; | |
087350c9 | 48 | |
666bfddb VG |
49 | /* Total size of vmcore file. */ |
50 | static u64 vmcore_size; | |
51 | ||
a05e16ad | 52 | static struct proc_dir_entry *proc_vmcore; |
666bfddb | 53 | |
2724273e RL |
54 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
55 | /* Device Dump list and mutex to synchronize access to list */ | |
56 | static LIST_HEAD(vmcoredd_list); | |
57 | static DEFINE_MUTEX(vmcoredd_mutex); | |
c6c40533 KS |
58 | |
59 | static bool vmcoredd_disabled; | |
60 | core_param(novmcoredd, vmcoredd_disabled, bool, 0); | |
2724273e RL |
61 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ |
62 | ||
7efe48df RL |
63 | /* Device Dump Size */ |
64 | static size_t vmcoredd_orig_sz; | |
65 | ||
5039b170 DH |
66 | static DEFINE_SPINLOCK(vmcore_cb_lock); |
67 | DEFINE_STATIC_SRCU(vmcore_cb_srcu); | |
cc5f2704 DH |
68 | /* List of registered vmcore callbacks. */ |
69 | static LIST_HEAD(vmcore_cb_list); | |
cc5f2704 DH |
70 | /* Whether the vmcore has been opened once. */ |
71 | static bool vmcore_opened; | |
72 | ||
73 | void register_vmcore_cb(struct vmcore_cb *cb) | |
997c136f | 74 | { |
cc5f2704 | 75 | INIT_LIST_HEAD(&cb->next); |
5039b170 | 76 | spin_lock(&vmcore_cb_lock); |
cc5f2704 DH |
77 | list_add_tail(&cb->next, &vmcore_cb_list); |
78 | /* | |
79 | * Registering a vmcore callback after the vmcore was opened is | |
80 | * very unusual (e.g., manual driver loading). | |
81 | */ | |
82 | if (vmcore_opened) | |
83 | pr_warn_once("Unexpected vmcore callback registration\n"); | |
5039b170 | 84 | spin_unlock(&vmcore_cb_lock); |
997c136f | 85 | } |
cc5f2704 | 86 | EXPORT_SYMBOL_GPL(register_vmcore_cb); |
997c136f | 87 | |
cc5f2704 | 88 | void unregister_vmcore_cb(struct vmcore_cb *cb) |
997c136f | 89 | { |
5039b170 DH |
90 | spin_lock(&vmcore_cb_lock); |
91 | list_del_rcu(&cb->next); | |
cc5f2704 DH |
92 | /* |
93 | * Unregistering a vmcore callback after the vmcore was opened is | |
94 | * very unusual (e.g., forced driver removal), but we cannot stop | |
95 | * unregistering. | |
96 | */ | |
25bc5b0d | 97 | if (vmcore_opened) |
cc5f2704 | 98 | pr_warn_once("Unexpected vmcore callback unregistration\n"); |
5039b170 DH |
99 | spin_unlock(&vmcore_cb_lock); |
100 | ||
101 | synchronize_srcu(&vmcore_cb_srcu); | |
997c136f | 102 | } |
cc5f2704 | 103 | EXPORT_SYMBOL_GPL(unregister_vmcore_cb); |
997c136f | 104 | |
2c9feeae | 105 | static bool pfn_is_ram(unsigned long pfn) |
997c136f | 106 | { |
cc5f2704 | 107 | struct vmcore_cb *cb; |
2c9feeae | 108 | bool ret = true; |
997c136f | 109 | |
5039b170 DH |
110 | list_for_each_entry_srcu(cb, &vmcore_cb_list, next, |
111 | srcu_read_lock_held(&vmcore_cb_srcu)) { | |
cc5f2704 DH |
112 | if (unlikely(!cb->pfn_is_ram)) |
113 | continue; | |
114 | ret = cb->pfn_is_ram(cb, pfn); | |
115 | if (!ret) | |
116 | break; | |
117 | } | |
997c136f OH |
118 | |
119 | return ret; | |
120 | } | |
121 | ||
cc5f2704 DH |
122 | static int open_vmcore(struct inode *inode, struct file *file) |
123 | { | |
5039b170 | 124 | spin_lock(&vmcore_cb_lock); |
cc5f2704 | 125 | vmcore_opened = true; |
5039b170 | 126 | spin_unlock(&vmcore_cb_lock); |
cc5f2704 DH |
127 | |
128 | return 0; | |
129 | } | |
130 | ||
666bfddb | 131 | /* Reads a page from the oldmem device from given offset. */ |
5d8de293 MWO |
132 | static ssize_t read_from_oldmem_iter(struct iov_iter *iter, size_t count, |
133 | u64 *ppos, bool encrypted) | |
666bfddb VG |
134 | { |
135 | unsigned long pfn, offset; | |
136 | size_t nr_bytes; | |
137 | ssize_t read = 0, tmp; | |
5039b170 | 138 | int idx; |
666bfddb VG |
139 | |
140 | if (!count) | |
141 | return 0; | |
142 | ||
143 | offset = (unsigned long)(*ppos % PAGE_SIZE); | |
144 | pfn = (unsigned long)(*ppos / PAGE_SIZE); | |
666bfddb | 145 | |
5039b170 | 146 | idx = srcu_read_lock(&vmcore_cb_srcu); |
666bfddb VG |
147 | do { |
148 | if (count > (PAGE_SIZE - offset)) | |
149 | nr_bytes = PAGE_SIZE - offset; | |
150 | else | |
151 | nr_bytes = count; | |
152 | ||
997c136f | 153 | /* If pfn is not ram, return zeros for sparse dump files */ |
c1e63117 | 154 | if (!pfn_is_ram(pfn)) { |
5d8de293 | 155 | tmp = iov_iter_zero(nr_bytes, iter); |
c1e63117 | 156 | } else { |
992b649a | 157 | if (encrypted) |
5d8de293 | 158 | tmp = copy_oldmem_page_encrypted(iter, pfn, |
992b649a | 159 | nr_bytes, |
5d8de293 | 160 | offset); |
992b649a | 161 | else |
5d8de293 MWO |
162 | tmp = copy_oldmem_page(iter, pfn, nr_bytes, |
163 | offset); | |
997c136f | 164 | } |
5d8de293 | 165 | if (tmp < nr_bytes) { |
5039b170 | 166 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
5d8de293 | 167 | return -EFAULT; |
c1e63117 DH |
168 | } |
169 | ||
666bfddb VG |
170 | *ppos += nr_bytes; |
171 | count -= nr_bytes; | |
666bfddb VG |
172 | read += nr_bytes; |
173 | ++pfn; | |
174 | offset = 0; | |
175 | } while (count); | |
5039b170 | 176 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
666bfddb VG |
177 | |
178 | return read; | |
179 | } | |
180 | ||
5d8de293 MWO |
181 | ssize_t read_from_oldmem(char *buf, size_t count, |
182 | u64 *ppos, int userbuf, | |
183 | bool encrypted) | |
184 | { | |
185 | struct iov_iter iter; | |
186 | struct iovec iov; | |
187 | struct kvec kvec; | |
188 | ||
189 | if (userbuf) { | |
190 | iov.iov_base = (__force void __user *)buf; | |
191 | iov.iov_len = count; | |
192 | iov_iter_init(&iter, READ, &iov, 1, count); | |
193 | } else { | |
194 | kvec.iov_base = buf; | |
195 | kvec.iov_len = count; | |
196 | iov_iter_kvec(&iter, READ, &kvec, 1, count); | |
197 | } | |
198 | ||
199 | return read_from_oldmem_iter(&iter, count, ppos, encrypted); | |
200 | } | |
201 | ||
be8a8d06 MH |
202 | /* |
203 | * Architectures may override this function to allocate ELF header in 2nd kernel | |
204 | */ | |
205 | int __weak elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) | |
206 | { | |
207 | return 0; | |
208 | } | |
209 | ||
210 | /* | |
211 | * Architectures may override this function to free header | |
212 | */ | |
213 | void __weak elfcorehdr_free(unsigned long long addr) | |
214 | {} | |
215 | ||
216 | /* | |
217 | * Architectures may override this function to read from ELF header | |
218 | */ | |
219 | ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos) | |
220 | { | |
ae7eb82a | 221 | return read_from_oldmem(buf, count, ppos, 0, false); |
be8a8d06 MH |
222 | } |
223 | ||
224 | /* | |
225 | * Architectures may override this function to read from notes sections | |
226 | */ | |
227 | ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) | |
228 | { | |
e9d1d2bb | 229 | return read_from_oldmem(buf, count, ppos, 0, cc_platform_has(CC_ATTR_MEM_ENCRYPT)); |
be8a8d06 MH |
230 | } |
231 | ||
9cb21813 MH |
232 | /* |
233 | * Architectures may override this function to map oldmem | |
234 | */ | |
235 | int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma, | |
236 | unsigned long from, unsigned long pfn, | |
237 | unsigned long size, pgprot_t prot) | |
238 | { | |
992b649a | 239 | prot = pgprot_encrypted(prot); |
9cb21813 MH |
240 | return remap_pfn_range(vma, from, pfn, size, prot); |
241 | } | |
242 | ||
cf089611 BP |
243 | /* |
244 | * Architectures which support memory encryption override this. | |
245 | */ | |
5d8de293 MWO |
246 | ssize_t __weak copy_oldmem_page_encrypted(struct iov_iter *iter, |
247 | unsigned long pfn, size_t csize, unsigned long offset) | |
cf089611 | 248 | { |
5d8de293 | 249 | return copy_oldmem_page(iter, pfn, csize, offset); |
cf089611 BP |
250 | } |
251 | ||
7efe48df | 252 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
4a22fd20 | 253 | static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size) |
7efe48df RL |
254 | { |
255 | struct vmcoredd_node *dump; | |
256 | u64 offset = 0; | |
257 | int ret = 0; | |
258 | size_t tsz; | |
259 | char *buf; | |
260 | ||
261 | mutex_lock(&vmcoredd_mutex); | |
262 | list_for_each_entry(dump, &vmcoredd_list, list) { | |
263 | if (start < offset + dump->size) { | |
264 | tsz = min(offset + (u64)dump->size - start, (u64)size); | |
265 | buf = dump->buf + start - offset; | |
4a22fd20 | 266 | if (copy_to_iter(buf, tsz, iter) < tsz) { |
7efe48df RL |
267 | ret = -EFAULT; |
268 | goto out_unlock; | |
269 | } | |
270 | ||
271 | size -= tsz; | |
272 | start += tsz; | |
7efe48df RL |
273 | |
274 | /* Leave now if buffer filled already */ | |
275 | if (!size) | |
276 | goto out_unlock; | |
277 | } | |
278 | offset += dump->size; | |
279 | } | |
280 | ||
281 | out_unlock: | |
282 | mutex_unlock(&vmcoredd_mutex); | |
283 | return ret; | |
284 | } | |
285 | ||
a2036a1e | 286 | #ifdef CONFIG_MMU |
7efe48df RL |
287 | static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst, |
288 | u64 start, size_t size) | |
289 | { | |
290 | struct vmcoredd_node *dump; | |
291 | u64 offset = 0; | |
292 | int ret = 0; | |
293 | size_t tsz; | |
294 | char *buf; | |
295 | ||
296 | mutex_lock(&vmcoredd_mutex); | |
297 | list_for_each_entry(dump, &vmcoredd_list, list) { | |
298 | if (start < offset + dump->size) { | |
299 | tsz = min(offset + (u64)dump->size - start, (u64)size); | |
300 | buf = dump->buf + start - offset; | |
bdebd6a2 JH |
301 | if (remap_vmalloc_range_partial(vma, dst, buf, 0, |
302 | tsz)) { | |
7efe48df RL |
303 | ret = -EFAULT; |
304 | goto out_unlock; | |
305 | } | |
306 | ||
307 | size -= tsz; | |
308 | start += tsz; | |
309 | dst += tsz; | |
310 | ||
311 | /* Leave now if buffer filled already */ | |
312 | if (!size) | |
313 | goto out_unlock; | |
314 | } | |
315 | offset += dump->size; | |
316 | } | |
317 | ||
318 | out_unlock: | |
319 | mutex_unlock(&vmcoredd_mutex); | |
320 | return ret; | |
321 | } | |
a2036a1e | 322 | #endif /* CONFIG_MMU */ |
7efe48df RL |
323 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ |
324 | ||
666bfddb VG |
325 | /* Read from the ELF header and then the crash dump. On error, negative value is |
326 | * returned otherwise number of bytes read are returned. | |
327 | */ | |
4a22fd20 | 328 | static ssize_t __read_vmcore(struct iov_iter *iter, loff_t *fpos) |
666bfddb VG |
329 | { |
330 | ssize_t acc = 0, tmp; | |
80e8ff63 | 331 | size_t tsz; |
b27eb186 HD |
332 | u64 start; |
333 | struct vmcore *m = NULL; | |
666bfddb | 334 | |
4a22fd20 | 335 | if (!iov_iter_count(iter) || *fpos >= vmcore_size) |
666bfddb VG |
336 | return 0; |
337 | ||
4a22fd20 | 338 | iov_iter_truncate(iter, vmcore_size - *fpos); |
666bfddb VG |
339 | |
340 | /* Read ELF core header */ | |
341 | if (*fpos < elfcorebuf_sz) { | |
4a22fd20 MWO |
342 | tsz = min(elfcorebuf_sz - (size_t)*fpos, iov_iter_count(iter)); |
343 | if (copy_to_iter(elfcorebuf + *fpos, tsz, iter) < tsz) | |
666bfddb | 344 | return -EFAULT; |
666bfddb | 345 | *fpos += tsz; |
666bfddb VG |
346 | acc += tsz; |
347 | ||
348 | /* leave now if filled buffer already */ | |
4a22fd20 | 349 | if (!iov_iter_count(iter)) |
666bfddb VG |
350 | return acc; |
351 | } | |
352 | ||
087350c9 HD |
353 | /* Read Elf note segment */ |
354 | if (*fpos < elfcorebuf_sz + elfnotes_sz) { | |
355 | void *kaddr; | |
356 | ||
7efe48df RL |
357 | /* We add device dumps before other elf notes because the |
358 | * other elf notes may not fill the elf notes buffer | |
359 | * completely and we will end up with zero-filled data | |
360 | * between the elf notes and the device dumps. Tools will | |
361 | * then try to decode this zero-filled data as valid notes | |
362 | * and we don't want that. Hence, adding device dumps before | |
363 | * the other elf notes ensure that zero-filled data can be | |
364 | * avoided. | |
365 | */ | |
366 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
367 | /* Read device dumps */ | |
368 | if (*fpos < elfcorebuf_sz + vmcoredd_orig_sz) { | |
369 | tsz = min(elfcorebuf_sz + vmcoredd_orig_sz - | |
4a22fd20 | 370 | (size_t)*fpos, iov_iter_count(iter)); |
7efe48df | 371 | start = *fpos - elfcorebuf_sz; |
4a22fd20 | 372 | if (vmcoredd_copy_dumps(iter, start, tsz)) |
7efe48df RL |
373 | return -EFAULT; |
374 | ||
7efe48df | 375 | *fpos += tsz; |
7efe48df RL |
376 | acc += tsz; |
377 | ||
378 | /* leave now if filled buffer already */ | |
4a22fd20 | 379 | if (!iov_iter_count(iter)) |
7efe48df RL |
380 | return acc; |
381 | } | |
382 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
383 | ||
384 | /* Read remaining elf notes */ | |
4a22fd20 MWO |
385 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, |
386 | iov_iter_count(iter)); | |
7efe48df | 387 | kaddr = elfnotes_buf + *fpos - elfcorebuf_sz - vmcoredd_orig_sz; |
4a22fd20 | 388 | if (copy_to_iter(kaddr, tsz, iter) < tsz) |
087350c9 | 389 | return -EFAULT; |
7efe48df | 390 | |
087350c9 | 391 | *fpos += tsz; |
087350c9 HD |
392 | acc += tsz; |
393 | ||
394 | /* leave now if filled buffer already */ | |
4a22fd20 | 395 | if (!iov_iter_count(iter)) |
087350c9 HD |
396 | return acc; |
397 | } | |
398 | ||
b27eb186 HD |
399 | list_for_each_entry(m, &vmcore_list, list) { |
400 | if (*fpos < m->offset + m->size) { | |
0b50a2d8 DY |
401 | tsz = (size_t)min_t(unsigned long long, |
402 | m->offset + m->size - *fpos, | |
4a22fd20 | 403 | iov_iter_count(iter)); |
b27eb186 | 404 | start = m->paddr + *fpos - m->offset; |
4a22fd20 MWO |
405 | tmp = read_from_oldmem_iter(iter, tsz, &start, |
406 | cc_platform_has(CC_ATTR_MEM_ENCRYPT)); | |
b27eb186 HD |
407 | if (tmp < 0) |
408 | return tmp; | |
b27eb186 | 409 | *fpos += tsz; |
b27eb186 HD |
410 | acc += tsz; |
411 | ||
412 | /* leave now if filled buffer already */ | |
4a22fd20 | 413 | if (!iov_iter_count(iter)) |
b27eb186 | 414 | return acc; |
666bfddb | 415 | } |
666bfddb | 416 | } |
b27eb186 | 417 | |
666bfddb VG |
418 | return acc; |
419 | } | |
420 | ||
4a22fd20 | 421 | static ssize_t read_vmcore(struct kiocb *iocb, struct iov_iter *iter) |
9cb21813 | 422 | { |
4a22fd20 | 423 | return __read_vmcore(iter, &iocb->ki_pos); |
9cb21813 MH |
424 | } |
425 | ||
426 | /* | |
427 | * The vmcore fault handler uses the page cache and fills data using the | |
4a22fd20 | 428 | * standard __read_vmcore() function. |
9cb21813 MH |
429 | * |
430 | * On s390 the fault handler is used for memory regions that can't be mapped | |
431 | * directly with remap_pfn_range(). | |
432 | */ | |
36f06204 | 433 | static vm_fault_t mmap_vmcore_fault(struct vm_fault *vmf) |
9cb21813 MH |
434 | { |
435 | #ifdef CONFIG_S390 | |
11bac800 | 436 | struct address_space *mapping = vmf->vma->vm_file->f_mapping; |
9cb21813 | 437 | pgoff_t index = vmf->pgoff; |
4a22fd20 MWO |
438 | struct iov_iter iter; |
439 | struct kvec kvec; | |
9cb21813 MH |
440 | struct page *page; |
441 | loff_t offset; | |
9cb21813 MH |
442 | int rc; |
443 | ||
444 | page = find_or_create_page(mapping, index, GFP_KERNEL); | |
445 | if (!page) | |
446 | return VM_FAULT_OOM; | |
447 | if (!PageUptodate(page)) { | |
09cbfeaf | 448 | offset = (loff_t) index << PAGE_SHIFT; |
4a22fd20 MWO |
449 | kvec.iov_base = page_address(page); |
450 | kvec.iov_len = PAGE_SIZE; | |
451 | iov_iter_kvec(&iter, READ, &kvec, 1, PAGE_SIZE); | |
452 | ||
453 | rc = __read_vmcore(&iter, &offset); | |
9cb21813 MH |
454 | if (rc < 0) { |
455 | unlock_page(page); | |
09cbfeaf | 456 | put_page(page); |
b5c21237 | 457 | return vmf_error(rc); |
9cb21813 MH |
458 | } |
459 | SetPageUptodate(page); | |
460 | } | |
461 | unlock_page(page); | |
462 | vmf->page = page; | |
463 | return 0; | |
464 | #else | |
465 | return VM_FAULT_SIGBUS; | |
466 | #endif | |
467 | } | |
468 | ||
469 | static const struct vm_operations_struct vmcore_mmap_ops = { | |
470 | .fault = mmap_vmcore_fault, | |
471 | }; | |
472 | ||
83086978 | 473 | /** |
2724273e | 474 | * vmcore_alloc_buf - allocate buffer in vmalloc memory |
e9f5d101 | 475 | * @size: size of buffer |
83086978 HD |
476 | * |
477 | * If CONFIG_MMU is defined, use vmalloc_user() to allow users to mmap | |
478 | * the buffer to user-space by means of remap_vmalloc_range(). | |
479 | * | |
480 | * If CONFIG_MMU is not defined, use vzalloc() since mmap_vmcore() is | |
481 | * disabled and there's no need to allow users to mmap the buffer. | |
482 | */ | |
2724273e | 483 | static inline char *vmcore_alloc_buf(size_t size) |
83086978 HD |
484 | { |
485 | #ifdef CONFIG_MMU | |
2724273e | 486 | return vmalloc_user(size); |
83086978 | 487 | #else |
2724273e | 488 | return vzalloc(size); |
83086978 HD |
489 | #endif |
490 | } | |
491 | ||
492 | /* | |
493 | * Disable mmap_vmcore() if CONFIG_MMU is not defined. MMU is | |
494 | * essential for mmap_vmcore() in order to map physically | |
495 | * non-contiguous objects (ELF header, ELF note segment and memory | |
496 | * regions in the 1st kernel pointed to by PT_LOAD entries) into | |
497 | * virtually contiguous user-space in ELF layout. | |
498 | */ | |
11e376a3 | 499 | #ifdef CONFIG_MMU |
0692dedc VK |
500 | /* |
501 | * remap_oldmem_pfn_checked - do remap_oldmem_pfn_range replacing all pages | |
502 | * reported as not being ram with the zero page. | |
503 | * | |
504 | * @vma: vm_area_struct describing requested mapping | |
505 | * @from: start remapping from | |
506 | * @pfn: page frame number to start remapping to | |
507 | * @size: remapping size | |
508 | * @prot: protection bits | |
509 | * | |
510 | * Returns zero on success, -EAGAIN on failure. | |
511 | */ | |
512 | static int remap_oldmem_pfn_checked(struct vm_area_struct *vma, | |
513 | unsigned long from, unsigned long pfn, | |
514 | unsigned long size, pgprot_t prot) | |
515 | { | |
516 | unsigned long map_size; | |
517 | unsigned long pos_start, pos_end, pos; | |
518 | unsigned long zeropage_pfn = my_zero_pfn(0); | |
519 | size_t len = 0; | |
520 | ||
521 | pos_start = pfn; | |
522 | pos_end = pfn + (size >> PAGE_SHIFT); | |
523 | ||
524 | for (pos = pos_start; pos < pos_end; ++pos) { | |
525 | if (!pfn_is_ram(pos)) { | |
526 | /* | |
527 | * We hit a page which is not ram. Remap the continuous | |
528 | * region between pos_start and pos-1 and replace | |
529 | * the non-ram page at pos with the zero page. | |
530 | */ | |
531 | if (pos > pos_start) { | |
532 | /* Remap continuous region */ | |
533 | map_size = (pos - pos_start) << PAGE_SHIFT; | |
534 | if (remap_oldmem_pfn_range(vma, from + len, | |
535 | pos_start, map_size, | |
536 | prot)) | |
537 | goto fail; | |
538 | len += map_size; | |
539 | } | |
540 | /* Remap the zero page */ | |
541 | if (remap_oldmem_pfn_range(vma, from + len, | |
542 | zeropage_pfn, | |
543 | PAGE_SIZE, prot)) | |
544 | goto fail; | |
545 | len += PAGE_SIZE; | |
546 | pos_start = pos + 1; | |
547 | } | |
548 | } | |
549 | if (pos > pos_start) { | |
550 | /* Remap the rest */ | |
551 | map_size = (pos - pos_start) << PAGE_SHIFT; | |
552 | if (remap_oldmem_pfn_range(vma, from + len, pos_start, | |
553 | map_size, prot)) | |
554 | goto fail; | |
555 | } | |
556 | return 0; | |
557 | fail: | |
897ab3e0 | 558 | do_munmap(vma->vm_mm, from, len, NULL); |
0692dedc VK |
559 | return -EAGAIN; |
560 | } | |
561 | ||
562 | static int vmcore_remap_oldmem_pfn(struct vm_area_struct *vma, | |
563 | unsigned long from, unsigned long pfn, | |
564 | unsigned long size, pgprot_t prot) | |
565 | { | |
5039b170 | 566 | int ret, idx; |
cc5f2704 | 567 | |
0692dedc | 568 | /* |
5039b170 DH |
569 | * Check if a callback was registered to avoid looping over all |
570 | * pages without a reason. | |
0692dedc | 571 | */ |
5039b170 | 572 | idx = srcu_read_lock(&vmcore_cb_srcu); |
25bc5b0d | 573 | if (!list_empty(&vmcore_cb_list)) |
cc5f2704 | 574 | ret = remap_oldmem_pfn_checked(vma, from, pfn, size, prot); |
0692dedc | 575 | else |
cc5f2704 | 576 | ret = remap_oldmem_pfn_range(vma, from, pfn, size, prot); |
5039b170 | 577 | srcu_read_unlock(&vmcore_cb_srcu, idx); |
cc5f2704 | 578 | return ret; |
0692dedc VK |
579 | } |
580 | ||
83086978 HD |
581 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) |
582 | { | |
583 | size_t size = vma->vm_end - vma->vm_start; | |
584 | u64 start, end, len, tsz; | |
585 | struct vmcore *m; | |
586 | ||
587 | start = (u64)vma->vm_pgoff << PAGE_SHIFT; | |
588 | end = start + size; | |
589 | ||
590 | if (size > vmcore_size || end > vmcore_size) | |
591 | return -EINVAL; | |
592 | ||
593 | if (vma->vm_flags & (VM_WRITE | VM_EXEC)) | |
594 | return -EPERM; | |
595 | ||
596 | vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC); | |
597 | vma->vm_flags |= VM_MIXEDMAP; | |
9cb21813 | 598 | vma->vm_ops = &vmcore_mmap_ops; |
83086978 HD |
599 | |
600 | len = 0; | |
601 | ||
602 | if (start < elfcorebuf_sz) { | |
603 | u64 pfn; | |
604 | ||
605 | tsz = min(elfcorebuf_sz - (size_t)start, size); | |
606 | pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT; | |
607 | if (remap_pfn_range(vma, vma->vm_start, pfn, tsz, | |
608 | vma->vm_page_prot)) | |
609 | return -EAGAIN; | |
610 | size -= tsz; | |
611 | start += tsz; | |
612 | len += tsz; | |
613 | ||
614 | if (size == 0) | |
615 | return 0; | |
616 | } | |
617 | ||
618 | if (start < elfcorebuf_sz + elfnotes_sz) { | |
619 | void *kaddr; | |
620 | ||
7efe48df RL |
621 | /* We add device dumps before other elf notes because the |
622 | * other elf notes may not fill the elf notes buffer | |
623 | * completely and we will end up with zero-filled data | |
624 | * between the elf notes and the device dumps. Tools will | |
625 | * then try to decode this zero-filled data as valid notes | |
626 | * and we don't want that. Hence, adding device dumps before | |
627 | * the other elf notes ensure that zero-filled data can be | |
628 | * avoided. This also ensures that the device dumps and | |
629 | * other elf notes can be properly mmaped at page aligned | |
630 | * address. | |
631 | */ | |
632 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
633 | /* Read device dumps */ | |
634 | if (start < elfcorebuf_sz + vmcoredd_orig_sz) { | |
635 | u64 start_off; | |
636 | ||
637 | tsz = min(elfcorebuf_sz + vmcoredd_orig_sz - | |
638 | (size_t)start, size); | |
639 | start_off = start - elfcorebuf_sz; | |
640 | if (vmcoredd_mmap_dumps(vma, vma->vm_start + len, | |
641 | start_off, tsz)) | |
642 | goto fail; | |
643 | ||
644 | size -= tsz; | |
645 | start += tsz; | |
646 | len += tsz; | |
647 | ||
648 | /* leave now if filled buffer already */ | |
649 | if (!size) | |
650 | return 0; | |
651 | } | |
652 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
653 | ||
654 | /* Read remaining elf notes */ | |
83086978 | 655 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size); |
7efe48df | 656 | kaddr = elfnotes_buf + start - elfcorebuf_sz - vmcoredd_orig_sz; |
83086978 | 657 | if (remap_vmalloc_range_partial(vma, vma->vm_start + len, |
bdebd6a2 | 658 | kaddr, 0, tsz)) |
83086978 | 659 | goto fail; |
7efe48df | 660 | |
83086978 HD |
661 | size -= tsz; |
662 | start += tsz; | |
663 | len += tsz; | |
664 | ||
665 | if (size == 0) | |
666 | return 0; | |
667 | } | |
668 | ||
669 | list_for_each_entry(m, &vmcore_list, list) { | |
670 | if (start < m->offset + m->size) { | |
671 | u64 paddr = 0; | |
672 | ||
0b50a2d8 DY |
673 | tsz = (size_t)min_t(unsigned long long, |
674 | m->offset + m->size - start, size); | |
83086978 | 675 | paddr = m->paddr + start - m->offset; |
0692dedc VK |
676 | if (vmcore_remap_oldmem_pfn(vma, vma->vm_start + len, |
677 | paddr >> PAGE_SHIFT, tsz, | |
678 | vma->vm_page_prot)) | |
83086978 HD |
679 | goto fail; |
680 | size -= tsz; | |
681 | start += tsz; | |
682 | len += tsz; | |
683 | ||
684 | if (size == 0) | |
685 | return 0; | |
686 | } | |
687 | } | |
688 | ||
689 | return 0; | |
690 | fail: | |
897ab3e0 | 691 | do_munmap(vma->vm_mm, vma->vm_start, len, NULL); |
83086978 HD |
692 | return -EAGAIN; |
693 | } | |
694 | #else | |
695 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) | |
696 | { | |
697 | return -ENOSYS; | |
698 | } | |
699 | #endif | |
700 | ||
97a32539 | 701 | static const struct proc_ops vmcore_proc_ops = { |
cc5f2704 | 702 | .proc_open = open_vmcore, |
4a22fd20 | 703 | .proc_read_iter = read_vmcore, |
97a32539 AD |
704 | .proc_lseek = default_llseek, |
705 | .proc_mmap = mmap_vmcore, | |
666bfddb VG |
706 | }; |
707 | ||
708 | static struct vmcore* __init get_new_element(void) | |
709 | { | |
2f6d3110 | 710 | return kzalloc(sizeof(struct vmcore), GFP_KERNEL); |
666bfddb VG |
711 | } |
712 | ||
44c752fe RL |
713 | static u64 get_vmcore_size(size_t elfsz, size_t elfnotesegsz, |
714 | struct list_head *vc_list) | |
666bfddb | 715 | { |
666bfddb | 716 | u64 size; |
591ff716 | 717 | struct vmcore *m; |
72658e9d | 718 | |
591ff716 HD |
719 | size = elfsz + elfnotesegsz; |
720 | list_for_each_entry(m, vc_list, list) { | |
721 | size += m->size; | |
72658e9d VG |
722 | } |
723 | return size; | |
724 | } | |
725 | ||
087350c9 HD |
726 | /** |
727 | * update_note_header_size_elf64 - update p_memsz member of each PT_NOTE entry | |
728 | * | |
729 | * @ehdr_ptr: ELF header | |
730 | * | |
731 | * This function updates p_memsz member of each PT_NOTE entry in the | |
732 | * program header table pointed to by @ehdr_ptr to real size of ELF | |
733 | * note segment. | |
734 | */ | |
735 | static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr) | |
666bfddb | 736 | { |
087350c9 HD |
737 | int i, rc=0; |
738 | Elf64_Phdr *phdr_ptr; | |
666bfddb | 739 | Elf64_Nhdr *nhdr_ptr; |
666bfddb | 740 | |
087350c9 | 741 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); |
666bfddb | 742 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
666bfddb | 743 | void *notes_section; |
666bfddb VG |
744 | u64 offset, max_sz, sz, real_sz = 0; |
745 | if (phdr_ptr->p_type != PT_NOTE) | |
746 | continue; | |
666bfddb VG |
747 | max_sz = phdr_ptr->p_memsz; |
748 | offset = phdr_ptr->p_offset; | |
749 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
750 | if (!notes_section) | |
751 | return -ENOMEM; | |
be8a8d06 | 752 | rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); |
666bfddb VG |
753 | if (rc < 0) { |
754 | kfree(notes_section); | |
755 | return rc; | |
756 | } | |
757 | nhdr_ptr = notes_section; | |
38dfac84 | 758 | while (nhdr_ptr->n_namesz != 0) { |
666bfddb | 759 | sz = sizeof(Elf64_Nhdr) + |
34b47764 WC |
760 | (((u64)nhdr_ptr->n_namesz + 3) & ~3) + |
761 | (((u64)nhdr_ptr->n_descsz + 3) & ~3); | |
38dfac84 GP |
762 | if ((real_sz + sz) > max_sz) { |
763 | pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n", | |
764 | nhdr_ptr->n_namesz, nhdr_ptr->n_descsz); | |
765 | break; | |
766 | } | |
666bfddb VG |
767 | real_sz += sz; |
768 | nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz); | |
769 | } | |
666bfddb | 770 | kfree(notes_section); |
087350c9 | 771 | phdr_ptr->p_memsz = real_sz; |
38dfac84 GP |
772 | if (real_sz == 0) { |
773 | pr_warn("Warning: Zero PT_NOTE entries found\n"); | |
38dfac84 | 774 | } |
666bfddb VG |
775 | } |
776 | ||
087350c9 HD |
777 | return 0; |
778 | } | |
779 | ||
780 | /** | |
781 | * get_note_number_and_size_elf64 - get the number of PT_NOTE program | |
782 | * headers and sum of real size of their ELF note segment headers and | |
783 | * data. | |
784 | * | |
785 | * @ehdr_ptr: ELF header | |
786 | * @nr_ptnote: buffer for the number of PT_NOTE program headers | |
787 | * @sz_ptnote: buffer for size of unique PT_NOTE program header | |
788 | * | |
789 | * This function is used to merge multiple PT_NOTE program headers | |
790 | * into a unique single one. The resulting unique entry will have | |
791 | * @sz_ptnote in its phdr->p_mem. | |
792 | * | |
793 | * It is assumed that program headers with PT_NOTE type pointed to by | |
794 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 | |
795 | * and each of PT_NOTE program headers has actual ELF note segment | |
796 | * size in its p_memsz member. | |
797 | */ | |
798 | static int __init get_note_number_and_size_elf64(const Elf64_Ehdr *ehdr_ptr, | |
799 | int *nr_ptnote, u64 *sz_ptnote) | |
800 | { | |
801 | int i; | |
802 | Elf64_Phdr *phdr_ptr; | |
803 | ||
804 | *nr_ptnote = *sz_ptnote = 0; | |
805 | ||
806 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); | |
807 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
808 | if (phdr_ptr->p_type != PT_NOTE) | |
809 | continue; | |
810 | *nr_ptnote += 1; | |
811 | *sz_ptnote += phdr_ptr->p_memsz; | |
812 | } | |
813 | ||
814 | return 0; | |
815 | } | |
816 | ||
817 | /** | |
818 | * copy_notes_elf64 - copy ELF note segments in a given buffer | |
819 | * | |
820 | * @ehdr_ptr: ELF header | |
821 | * @notes_buf: buffer into which ELF note segments are copied | |
822 | * | |
823 | * This function is used to copy ELF note segment in the 1st kernel | |
824 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that | |
825 | * size of the buffer @notes_buf is equal to or larger than sum of the | |
826 | * real ELF note segment headers and data. | |
827 | * | |
828 | * It is assumed that program headers with PT_NOTE type pointed to by | |
829 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 | |
830 | * and each of PT_NOTE program headers has actual ELF note segment | |
831 | * size in its p_memsz member. | |
832 | */ | |
833 | static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf) | |
834 | { | |
835 | int i, rc=0; | |
836 | Elf64_Phdr *phdr_ptr; | |
837 | ||
838 | phdr_ptr = (Elf64_Phdr*)(ehdr_ptr + 1); | |
839 | ||
840 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
841 | u64 offset; | |
842 | if (phdr_ptr->p_type != PT_NOTE) | |
843 | continue; | |
844 | offset = phdr_ptr->p_offset; | |
be8a8d06 MH |
845 | rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, |
846 | &offset); | |
087350c9 HD |
847 | if (rc < 0) |
848 | return rc; | |
849 | notes_buf += phdr_ptr->p_memsz; | |
850 | } | |
851 | ||
852 | return 0; | |
853 | } | |
854 | ||
855 | /* Merges all the PT_NOTE headers into one. */ | |
856 | static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, | |
857 | char **notes_buf, size_t *notes_sz) | |
858 | { | |
859 | int i, nr_ptnote=0, rc=0; | |
860 | char *tmp; | |
861 | Elf64_Ehdr *ehdr_ptr; | |
862 | Elf64_Phdr phdr; | |
863 | u64 phdr_sz = 0, note_off; | |
864 | ||
865 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
866 | ||
867 | rc = update_note_header_size_elf64(ehdr_ptr); | |
868 | if (rc < 0) | |
869 | return rc; | |
870 | ||
871 | rc = get_note_number_and_size_elf64(ehdr_ptr, &nr_ptnote, &phdr_sz); | |
872 | if (rc < 0) | |
873 | return rc; | |
874 | ||
875 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); | |
2724273e | 876 | *notes_buf = vmcore_alloc_buf(*notes_sz); |
087350c9 HD |
877 | if (!*notes_buf) |
878 | return -ENOMEM; | |
879 | ||
880 | rc = copy_notes_elf64(ehdr_ptr, *notes_buf); | |
881 | if (rc < 0) | |
882 | return rc; | |
883 | ||
666bfddb VG |
884 | /* Prepare merged PT_NOTE program header. */ |
885 | phdr.p_type = PT_NOTE; | |
886 | phdr.p_flags = 0; | |
887 | note_off = sizeof(Elf64_Ehdr) + | |
888 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr); | |
087350c9 | 889 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
666bfddb VG |
890 | phdr.p_vaddr = phdr.p_paddr = 0; |
891 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
892 | phdr.p_align = 0; | |
893 | ||
894 | /* Add merged PT_NOTE program header*/ | |
895 | tmp = elfptr + sizeof(Elf64_Ehdr); | |
896 | memcpy(tmp, &phdr, sizeof(phdr)); | |
897 | tmp += sizeof(phdr); | |
898 | ||
899 | /* Remove unwanted PT_NOTE program headers. */ | |
900 | i = (nr_ptnote - 1) * sizeof(Elf64_Phdr); | |
901 | *elfsz = *elfsz - i; | |
902 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr))); | |
f2bdacdd HD |
903 | memset(elfptr + *elfsz, 0, i); |
904 | *elfsz = roundup(*elfsz, PAGE_SIZE); | |
666bfddb VG |
905 | |
906 | /* Modify e_phnum to reflect merged headers. */ | |
907 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
908 | ||
7efe48df RL |
909 | /* Store the size of all notes. We need this to update the note |
910 | * header when the device dumps will be added. | |
911 | */ | |
912 | elfnotes_orig_sz = phdr.p_memsz; | |
913 | ||
666bfddb VG |
914 | return 0; |
915 | } | |
916 | ||
087350c9 HD |
917 | /** |
918 | * update_note_header_size_elf32 - update p_memsz member of each PT_NOTE entry | |
919 | * | |
920 | * @ehdr_ptr: ELF header | |
921 | * | |
922 | * This function updates p_memsz member of each PT_NOTE entry in the | |
923 | * program header table pointed to by @ehdr_ptr to real size of ELF | |
924 | * note segment. | |
925 | */ | |
926 | static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr) | |
72658e9d | 927 | { |
087350c9 HD |
928 | int i, rc=0; |
929 | Elf32_Phdr *phdr_ptr; | |
72658e9d | 930 | Elf32_Nhdr *nhdr_ptr; |
72658e9d | 931 | |
087350c9 | 932 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); |
72658e9d | 933 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
72658e9d | 934 | void *notes_section; |
72658e9d VG |
935 | u64 offset, max_sz, sz, real_sz = 0; |
936 | if (phdr_ptr->p_type != PT_NOTE) | |
937 | continue; | |
72658e9d VG |
938 | max_sz = phdr_ptr->p_memsz; |
939 | offset = phdr_ptr->p_offset; | |
940 | notes_section = kmalloc(max_sz, GFP_KERNEL); | |
941 | if (!notes_section) | |
942 | return -ENOMEM; | |
be8a8d06 | 943 | rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); |
72658e9d VG |
944 | if (rc < 0) { |
945 | kfree(notes_section); | |
946 | return rc; | |
947 | } | |
948 | nhdr_ptr = notes_section; | |
38dfac84 | 949 | while (nhdr_ptr->n_namesz != 0) { |
72658e9d | 950 | sz = sizeof(Elf32_Nhdr) + |
34b47764 WC |
951 | (((u64)nhdr_ptr->n_namesz + 3) & ~3) + |
952 | (((u64)nhdr_ptr->n_descsz + 3) & ~3); | |
38dfac84 GP |
953 | if ((real_sz + sz) > max_sz) { |
954 | pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n", | |
955 | nhdr_ptr->n_namesz, nhdr_ptr->n_descsz); | |
956 | break; | |
957 | } | |
72658e9d VG |
958 | real_sz += sz; |
959 | nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz); | |
960 | } | |
72658e9d | 961 | kfree(notes_section); |
087350c9 | 962 | phdr_ptr->p_memsz = real_sz; |
38dfac84 GP |
963 | if (real_sz == 0) { |
964 | pr_warn("Warning: Zero PT_NOTE entries found\n"); | |
38dfac84 | 965 | } |
087350c9 HD |
966 | } |
967 | ||
968 | return 0; | |
969 | } | |
970 | ||
971 | /** | |
972 | * get_note_number_and_size_elf32 - get the number of PT_NOTE program | |
973 | * headers and sum of real size of their ELF note segment headers and | |
974 | * data. | |
975 | * | |
976 | * @ehdr_ptr: ELF header | |
977 | * @nr_ptnote: buffer for the number of PT_NOTE program headers | |
978 | * @sz_ptnote: buffer for size of unique PT_NOTE program header | |
979 | * | |
980 | * This function is used to merge multiple PT_NOTE program headers | |
981 | * into a unique single one. The resulting unique entry will have | |
982 | * @sz_ptnote in its phdr->p_mem. | |
983 | * | |
984 | * It is assumed that program headers with PT_NOTE type pointed to by | |
985 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 | |
986 | * and each of PT_NOTE program headers has actual ELF note segment | |
987 | * size in its p_memsz member. | |
988 | */ | |
989 | static int __init get_note_number_and_size_elf32(const Elf32_Ehdr *ehdr_ptr, | |
990 | int *nr_ptnote, u64 *sz_ptnote) | |
991 | { | |
992 | int i; | |
993 | Elf32_Phdr *phdr_ptr; | |
994 | ||
995 | *nr_ptnote = *sz_ptnote = 0; | |
996 | ||
997 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); | |
998 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
999 | if (phdr_ptr->p_type != PT_NOTE) | |
1000 | continue; | |
1001 | *nr_ptnote += 1; | |
1002 | *sz_ptnote += phdr_ptr->p_memsz; | |
72658e9d VG |
1003 | } |
1004 | ||
087350c9 HD |
1005 | return 0; |
1006 | } | |
1007 | ||
1008 | /** | |
1009 | * copy_notes_elf32 - copy ELF note segments in a given buffer | |
1010 | * | |
1011 | * @ehdr_ptr: ELF header | |
1012 | * @notes_buf: buffer into which ELF note segments are copied | |
1013 | * | |
1014 | * This function is used to copy ELF note segment in the 1st kernel | |
1015 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that | |
1016 | * size of the buffer @notes_buf is equal to or larger than sum of the | |
1017 | * real ELF note segment headers and data. | |
1018 | * | |
1019 | * It is assumed that program headers with PT_NOTE type pointed to by | |
1020 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 | |
1021 | * and each of PT_NOTE program headers has actual ELF note segment | |
1022 | * size in its p_memsz member. | |
1023 | */ | |
1024 | static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf) | |
1025 | { | |
1026 | int i, rc=0; | |
1027 | Elf32_Phdr *phdr_ptr; | |
1028 | ||
1029 | phdr_ptr = (Elf32_Phdr*)(ehdr_ptr + 1); | |
1030 | ||
1031 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
1032 | u64 offset; | |
1033 | if (phdr_ptr->p_type != PT_NOTE) | |
1034 | continue; | |
1035 | offset = phdr_ptr->p_offset; | |
be8a8d06 MH |
1036 | rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, |
1037 | &offset); | |
087350c9 HD |
1038 | if (rc < 0) |
1039 | return rc; | |
1040 | notes_buf += phdr_ptr->p_memsz; | |
1041 | } | |
1042 | ||
1043 | return 0; | |
1044 | } | |
1045 | ||
1046 | /* Merges all the PT_NOTE headers into one. */ | |
1047 | static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, | |
1048 | char **notes_buf, size_t *notes_sz) | |
1049 | { | |
1050 | int i, nr_ptnote=0, rc=0; | |
1051 | char *tmp; | |
1052 | Elf32_Ehdr *ehdr_ptr; | |
1053 | Elf32_Phdr phdr; | |
1054 | u64 phdr_sz = 0, note_off; | |
1055 | ||
1056 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
1057 | ||
1058 | rc = update_note_header_size_elf32(ehdr_ptr); | |
1059 | if (rc < 0) | |
1060 | return rc; | |
1061 | ||
1062 | rc = get_note_number_and_size_elf32(ehdr_ptr, &nr_ptnote, &phdr_sz); | |
1063 | if (rc < 0) | |
1064 | return rc; | |
1065 | ||
1066 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); | |
2724273e | 1067 | *notes_buf = vmcore_alloc_buf(*notes_sz); |
087350c9 HD |
1068 | if (!*notes_buf) |
1069 | return -ENOMEM; | |
1070 | ||
1071 | rc = copy_notes_elf32(ehdr_ptr, *notes_buf); | |
1072 | if (rc < 0) | |
1073 | return rc; | |
1074 | ||
72658e9d VG |
1075 | /* Prepare merged PT_NOTE program header. */ |
1076 | phdr.p_type = PT_NOTE; | |
1077 | phdr.p_flags = 0; | |
1078 | note_off = sizeof(Elf32_Ehdr) + | |
1079 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr); | |
087350c9 | 1080 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
72658e9d VG |
1081 | phdr.p_vaddr = phdr.p_paddr = 0; |
1082 | phdr.p_filesz = phdr.p_memsz = phdr_sz; | |
1083 | phdr.p_align = 0; | |
1084 | ||
1085 | /* Add merged PT_NOTE program header*/ | |
1086 | tmp = elfptr + sizeof(Elf32_Ehdr); | |
1087 | memcpy(tmp, &phdr, sizeof(phdr)); | |
1088 | tmp += sizeof(phdr); | |
1089 | ||
1090 | /* Remove unwanted PT_NOTE program headers. */ | |
1091 | i = (nr_ptnote - 1) * sizeof(Elf32_Phdr); | |
1092 | *elfsz = *elfsz - i; | |
1093 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr))); | |
f2bdacdd HD |
1094 | memset(elfptr + *elfsz, 0, i); |
1095 | *elfsz = roundup(*elfsz, PAGE_SIZE); | |
72658e9d VG |
1096 | |
1097 | /* Modify e_phnum to reflect merged headers. */ | |
1098 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; | |
1099 | ||
7efe48df RL |
1100 | /* Store the size of all notes. We need this to update the note |
1101 | * header when the device dumps will be added. | |
1102 | */ | |
1103 | elfnotes_orig_sz = phdr.p_memsz; | |
1104 | ||
72658e9d VG |
1105 | return 0; |
1106 | } | |
1107 | ||
666bfddb VG |
1108 | /* Add memory chunks represented by program headers to vmcore list. Also update |
1109 | * the new offset fields of exported program headers. */ | |
1110 | static int __init process_ptload_program_headers_elf64(char *elfptr, | |
1111 | size_t elfsz, | |
087350c9 | 1112 | size_t elfnotes_sz, |
666bfddb VG |
1113 | struct list_head *vc_list) |
1114 | { | |
1115 | int i; | |
1116 | Elf64_Ehdr *ehdr_ptr; | |
1117 | Elf64_Phdr *phdr_ptr; | |
1118 | loff_t vmcore_off; | |
1119 | struct vmcore *new; | |
1120 | ||
1121 | ehdr_ptr = (Elf64_Ehdr *)elfptr; | |
1122 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ | |
1123 | ||
087350c9 HD |
1124 | /* Skip Elf header, program headers and Elf note segment. */ |
1125 | vmcore_off = elfsz + elfnotes_sz; | |
666bfddb VG |
1126 | |
1127 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
7f614cd1 HD |
1128 | u64 paddr, start, end, size; |
1129 | ||
666bfddb VG |
1130 | if (phdr_ptr->p_type != PT_LOAD) |
1131 | continue; | |
1132 | ||
7f614cd1 HD |
1133 | paddr = phdr_ptr->p_offset; |
1134 | start = rounddown(paddr, PAGE_SIZE); | |
1135 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); | |
1136 | size = end - start; | |
1137 | ||
666bfddb VG |
1138 | /* Add this contiguous chunk of memory to vmcore list.*/ |
1139 | new = get_new_element(); | |
1140 | if (!new) | |
1141 | return -ENOMEM; | |
7f614cd1 HD |
1142 | new->paddr = start; |
1143 | new->size = size; | |
666bfddb VG |
1144 | list_add_tail(&new->list, vc_list); |
1145 | ||
1146 | /* Update the program header offset. */ | |
7f614cd1 HD |
1147 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
1148 | vmcore_off = vmcore_off + size; | |
666bfddb VG |
1149 | } |
1150 | return 0; | |
1151 | } | |
1152 | ||
72658e9d VG |
1153 | static int __init process_ptload_program_headers_elf32(char *elfptr, |
1154 | size_t elfsz, | |
087350c9 | 1155 | size_t elfnotes_sz, |
72658e9d VG |
1156 | struct list_head *vc_list) |
1157 | { | |
1158 | int i; | |
1159 | Elf32_Ehdr *ehdr_ptr; | |
1160 | Elf32_Phdr *phdr_ptr; | |
1161 | loff_t vmcore_off; | |
1162 | struct vmcore *new; | |
1163 | ||
1164 | ehdr_ptr = (Elf32_Ehdr *)elfptr; | |
1165 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ | |
1166 | ||
087350c9 HD |
1167 | /* Skip Elf header, program headers and Elf note segment. */ |
1168 | vmcore_off = elfsz + elfnotes_sz; | |
72658e9d VG |
1169 | |
1170 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { | |
7f614cd1 HD |
1171 | u64 paddr, start, end, size; |
1172 | ||
72658e9d VG |
1173 | if (phdr_ptr->p_type != PT_LOAD) |
1174 | continue; | |
1175 | ||
7f614cd1 HD |
1176 | paddr = phdr_ptr->p_offset; |
1177 | start = rounddown(paddr, PAGE_SIZE); | |
1178 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); | |
1179 | size = end - start; | |
1180 | ||
72658e9d VG |
1181 | /* Add this contiguous chunk of memory to vmcore list.*/ |
1182 | new = get_new_element(); | |
1183 | if (!new) | |
1184 | return -ENOMEM; | |
7f614cd1 HD |
1185 | new->paddr = start; |
1186 | new->size = size; | |
72658e9d VG |
1187 | list_add_tail(&new->list, vc_list); |
1188 | ||
1189 | /* Update the program header offset */ | |
7f614cd1 HD |
1190 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
1191 | vmcore_off = vmcore_off + size; | |
72658e9d VG |
1192 | } |
1193 | return 0; | |
1194 | } | |
1195 | ||
666bfddb | 1196 | /* Sets offset fields of vmcore elements. */ |
7efe48df RL |
1197 | static void set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz, |
1198 | struct list_head *vc_list) | |
666bfddb VG |
1199 | { |
1200 | loff_t vmcore_off; | |
666bfddb VG |
1201 | struct vmcore *m; |
1202 | ||
087350c9 HD |
1203 | /* Skip Elf header, program headers and Elf note segment. */ |
1204 | vmcore_off = elfsz + elfnotes_sz; | |
666bfddb VG |
1205 | |
1206 | list_for_each_entry(m, vc_list, list) { | |
1207 | m->offset = vmcore_off; | |
1208 | vmcore_off += m->size; | |
1209 | } | |
1210 | } | |
1211 | ||
f2bdacdd | 1212 | static void free_elfcorebuf(void) |
72658e9d | 1213 | { |
f2bdacdd HD |
1214 | free_pages((unsigned long)elfcorebuf, get_order(elfcorebuf_sz_orig)); |
1215 | elfcorebuf = NULL; | |
087350c9 HD |
1216 | vfree(elfnotes_buf); |
1217 | elfnotes_buf = NULL; | |
72658e9d VG |
1218 | } |
1219 | ||
666bfddb VG |
1220 | static int __init parse_crash_elf64_headers(void) |
1221 | { | |
1222 | int rc=0; | |
1223 | Elf64_Ehdr ehdr; | |
1224 | u64 addr; | |
1225 | ||
1226 | addr = elfcorehdr_addr; | |
1227 | ||
1228 | /* Read Elf header */ | |
be8a8d06 | 1229 | rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf64_Ehdr), &addr); |
666bfddb VG |
1230 | if (rc < 0) |
1231 | return rc; | |
1232 | ||
1233 | /* Do some basic Verification. */ | |
1234 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
1235 | (ehdr.e_type != ET_CORE) || | |
9833c394 | 1236 | !vmcore_elf64_check_arch(&ehdr) || |
666bfddb VG |
1237 | ehdr.e_ident[EI_CLASS] != ELFCLASS64 || |
1238 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
1239 | ehdr.e_version != EV_CURRENT || | |
1240 | ehdr.e_ehsize != sizeof(Elf64_Ehdr) || | |
1241 | ehdr.e_phentsize != sizeof(Elf64_Phdr) || | |
1242 | ehdr.e_phnum == 0) { | |
87ebdc00 | 1243 | pr_warn("Warning: Core image elf header is not sane\n"); |
666bfddb VG |
1244 | return -EINVAL; |
1245 | } | |
1246 | ||
1247 | /* Read in all elf headers. */ | |
f2bdacdd HD |
1248 | elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) + |
1249 | ehdr.e_phnum * sizeof(Elf64_Phdr); | |
1250 | elfcorebuf_sz = elfcorebuf_sz_orig; | |
1251 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, | |
1252 | get_order(elfcorebuf_sz_orig)); | |
666bfddb VG |
1253 | if (!elfcorebuf) |
1254 | return -ENOMEM; | |
1255 | addr = elfcorehdr_addr; | |
be8a8d06 | 1256 | rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); |
f2bdacdd HD |
1257 | if (rc < 0) |
1258 | goto fail; | |
666bfddb VG |
1259 | |
1260 | /* Merge all PT_NOTE headers into one. */ | |
087350c9 HD |
1261 | rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, |
1262 | &elfnotes_buf, &elfnotes_sz); | |
f2bdacdd HD |
1263 | if (rc) |
1264 | goto fail; | |
666bfddb | 1265 | rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, |
087350c9 | 1266 | elfnotes_sz, &vmcore_list); |
f2bdacdd HD |
1267 | if (rc) |
1268 | goto fail; | |
087350c9 | 1269 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
666bfddb | 1270 | return 0; |
f2bdacdd HD |
1271 | fail: |
1272 | free_elfcorebuf(); | |
1273 | return rc; | |
666bfddb VG |
1274 | } |
1275 | ||
72658e9d VG |
1276 | static int __init parse_crash_elf32_headers(void) |
1277 | { | |
1278 | int rc=0; | |
1279 | Elf32_Ehdr ehdr; | |
1280 | u64 addr; | |
1281 | ||
1282 | addr = elfcorehdr_addr; | |
1283 | ||
1284 | /* Read Elf header */ | |
be8a8d06 | 1285 | rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf32_Ehdr), &addr); |
72658e9d VG |
1286 | if (rc < 0) |
1287 | return rc; | |
1288 | ||
1289 | /* Do some basic Verification. */ | |
1290 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || | |
1291 | (ehdr.e_type != ET_CORE) || | |
e55d5312 | 1292 | !vmcore_elf32_check_arch(&ehdr) || |
72658e9d VG |
1293 | ehdr.e_ident[EI_CLASS] != ELFCLASS32|| |
1294 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || | |
1295 | ehdr.e_version != EV_CURRENT || | |
1296 | ehdr.e_ehsize != sizeof(Elf32_Ehdr) || | |
1297 | ehdr.e_phentsize != sizeof(Elf32_Phdr) || | |
1298 | ehdr.e_phnum == 0) { | |
87ebdc00 | 1299 | pr_warn("Warning: Core image elf header is not sane\n"); |
72658e9d VG |
1300 | return -EINVAL; |
1301 | } | |
1302 | ||
1303 | /* Read in all elf headers. */ | |
f2bdacdd HD |
1304 | elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); |
1305 | elfcorebuf_sz = elfcorebuf_sz_orig; | |
1306 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, | |
1307 | get_order(elfcorebuf_sz_orig)); | |
72658e9d VG |
1308 | if (!elfcorebuf) |
1309 | return -ENOMEM; | |
1310 | addr = elfcorehdr_addr; | |
be8a8d06 | 1311 | rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); |
f2bdacdd HD |
1312 | if (rc < 0) |
1313 | goto fail; | |
72658e9d VG |
1314 | |
1315 | /* Merge all PT_NOTE headers into one. */ | |
087350c9 HD |
1316 | rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, |
1317 | &elfnotes_buf, &elfnotes_sz); | |
f2bdacdd HD |
1318 | if (rc) |
1319 | goto fail; | |
72658e9d | 1320 | rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, |
087350c9 | 1321 | elfnotes_sz, &vmcore_list); |
f2bdacdd HD |
1322 | if (rc) |
1323 | goto fail; | |
087350c9 | 1324 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
72658e9d | 1325 | return 0; |
f2bdacdd HD |
1326 | fail: |
1327 | free_elfcorebuf(); | |
1328 | return rc; | |
72658e9d VG |
1329 | } |
1330 | ||
666bfddb VG |
1331 | static int __init parse_crash_elf_headers(void) |
1332 | { | |
1333 | unsigned char e_ident[EI_NIDENT]; | |
1334 | u64 addr; | |
1335 | int rc=0; | |
1336 | ||
1337 | addr = elfcorehdr_addr; | |
be8a8d06 | 1338 | rc = elfcorehdr_read(e_ident, EI_NIDENT, &addr); |
666bfddb VG |
1339 | if (rc < 0) |
1340 | return rc; | |
1341 | if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { | |
87ebdc00 | 1342 | pr_warn("Warning: Core image elf header not found\n"); |
666bfddb VG |
1343 | return -EINVAL; |
1344 | } | |
1345 | ||
1346 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
1347 | rc = parse_crash_elf64_headers(); | |
1348 | if (rc) | |
1349 | return rc; | |
72658e9d VG |
1350 | } else if (e_ident[EI_CLASS] == ELFCLASS32) { |
1351 | rc = parse_crash_elf32_headers(); | |
1352 | if (rc) | |
1353 | return rc; | |
666bfddb | 1354 | } else { |
87ebdc00 | 1355 | pr_warn("Warning: Core image elf header is not sane\n"); |
666bfddb VG |
1356 | return -EINVAL; |
1357 | } | |
591ff716 HD |
1358 | |
1359 | /* Determine vmcore size. */ | |
1360 | vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, | |
1361 | &vmcore_list); | |
1362 | ||
666bfddb VG |
1363 | return 0; |
1364 | } | |
1365 | ||
2724273e RL |
1366 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP |
1367 | /** | |
1368 | * vmcoredd_write_header - Write vmcore device dump header at the | |
1369 | * beginning of the dump's buffer. | |
1370 | * @buf: Output buffer where the note is written | |
1371 | * @data: Dump info | |
1372 | * @size: Size of the dump | |
1373 | * | |
1374 | * Fills beginning of the dump's buffer with vmcore device dump header. | |
1375 | */ | |
1376 | static void vmcoredd_write_header(void *buf, struct vmcoredd_data *data, | |
1377 | u32 size) | |
1378 | { | |
1379 | struct vmcoredd_header *vdd_hdr = (struct vmcoredd_header *)buf; | |
1380 | ||
1381 | vdd_hdr->n_namesz = sizeof(vdd_hdr->name); | |
1382 | vdd_hdr->n_descsz = size + sizeof(vdd_hdr->dump_name); | |
1383 | vdd_hdr->n_type = NT_VMCOREDD; | |
1384 | ||
1385 | strncpy((char *)vdd_hdr->name, VMCOREDD_NOTE_NAME, | |
1386 | sizeof(vdd_hdr->name)); | |
1387 | memcpy(vdd_hdr->dump_name, data->dump_name, sizeof(vdd_hdr->dump_name)); | |
1388 | } | |
1389 | ||
7efe48df RL |
1390 | /** |
1391 | * vmcoredd_update_program_headers - Update all Elf program headers | |
1392 | * @elfptr: Pointer to elf header | |
1393 | * @elfnotesz: Size of elf notes aligned to page size | |
1394 | * @vmcoreddsz: Size of device dumps to be added to elf note header | |
1395 | * | |
1396 | * Determine type of Elf header (Elf64 or Elf32) and update the elf note size. | |
1397 | * Also update the offsets of all the program headers after the elf note header. | |
1398 | */ | |
1399 | static void vmcoredd_update_program_headers(char *elfptr, size_t elfnotesz, | |
1400 | size_t vmcoreddsz) | |
1401 | { | |
1402 | unsigned char *e_ident = (unsigned char *)elfptr; | |
1403 | u64 start, end, size; | |
1404 | loff_t vmcore_off; | |
1405 | u32 i; | |
1406 | ||
1407 | vmcore_off = elfcorebuf_sz + elfnotesz; | |
1408 | ||
1409 | if (e_ident[EI_CLASS] == ELFCLASS64) { | |
1410 | Elf64_Ehdr *ehdr = (Elf64_Ehdr *)elfptr; | |
1411 | Elf64_Phdr *phdr = (Elf64_Phdr *)(elfptr + sizeof(Elf64_Ehdr)); | |
1412 | ||
1413 | /* Update all program headers */ | |
1414 | for (i = 0; i < ehdr->e_phnum; i++, phdr++) { | |
1415 | if (phdr->p_type == PT_NOTE) { | |
1416 | /* Update note size */ | |
1417 | phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz; | |
1418 | phdr->p_filesz = phdr->p_memsz; | |
1419 | continue; | |
1420 | } | |
1421 | ||
1422 | start = rounddown(phdr->p_offset, PAGE_SIZE); | |
1423 | end = roundup(phdr->p_offset + phdr->p_memsz, | |
1424 | PAGE_SIZE); | |
1425 | size = end - start; | |
1426 | phdr->p_offset = vmcore_off + (phdr->p_offset - start); | |
1427 | vmcore_off += size; | |
1428 | } | |
1429 | } else { | |
1430 | Elf32_Ehdr *ehdr = (Elf32_Ehdr *)elfptr; | |
1431 | Elf32_Phdr *phdr = (Elf32_Phdr *)(elfptr + sizeof(Elf32_Ehdr)); | |
1432 | ||
1433 | /* Update all program headers */ | |
1434 | for (i = 0; i < ehdr->e_phnum; i++, phdr++) { | |
1435 | if (phdr->p_type == PT_NOTE) { | |
1436 | /* Update note size */ | |
1437 | phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz; | |
1438 | phdr->p_filesz = phdr->p_memsz; | |
1439 | continue; | |
1440 | } | |
1441 | ||
1442 | start = rounddown(phdr->p_offset, PAGE_SIZE); | |
1443 | end = roundup(phdr->p_offset + phdr->p_memsz, | |
1444 | PAGE_SIZE); | |
1445 | size = end - start; | |
1446 | phdr->p_offset = vmcore_off + (phdr->p_offset - start); | |
1447 | vmcore_off += size; | |
1448 | } | |
1449 | } | |
1450 | } | |
1451 | ||
1452 | /** | |
1453 | * vmcoredd_update_size - Update the total size of the device dumps and update | |
1454 | * Elf header | |
1455 | * @dump_size: Size of the current device dump to be added to total size | |
1456 | * | |
1457 | * Update the total size of all the device dumps and update the Elf program | |
1458 | * headers. Calculate the new offsets for the vmcore list and update the | |
1459 | * total vmcore size. | |
1460 | */ | |
1461 | static void vmcoredd_update_size(size_t dump_size) | |
1462 | { | |
1463 | vmcoredd_orig_sz += dump_size; | |
1464 | elfnotes_sz = roundup(elfnotes_orig_sz, PAGE_SIZE) + vmcoredd_orig_sz; | |
1465 | vmcoredd_update_program_headers(elfcorebuf, elfnotes_sz, | |
1466 | vmcoredd_orig_sz); | |
1467 | ||
1468 | /* Update vmcore list offsets */ | |
1469 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); | |
1470 | ||
1471 | vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, | |
1472 | &vmcore_list); | |
1473 | proc_vmcore->size = vmcore_size; | |
1474 | } | |
1475 | ||
2724273e RL |
1476 | /** |
1477 | * vmcore_add_device_dump - Add a buffer containing device dump to vmcore | |
1478 | * @data: dump info. | |
1479 | * | |
1480 | * Allocate a buffer and invoke the calling driver's dump collect routine. | |
1481 | * Write Elf note at the beginning of the buffer to indicate vmcore device | |
1482 | * dump and add the dump to global list. | |
1483 | */ | |
1484 | int vmcore_add_device_dump(struct vmcoredd_data *data) | |
1485 | { | |
1486 | struct vmcoredd_node *dump; | |
1487 | void *buf = NULL; | |
1488 | size_t data_size; | |
1489 | int ret; | |
1490 | ||
c6c40533 KS |
1491 | if (vmcoredd_disabled) { |
1492 | pr_err_once("Device dump is disabled\n"); | |
1493 | return -EINVAL; | |
1494 | } | |
1495 | ||
2724273e RL |
1496 | if (!data || !strlen(data->dump_name) || |
1497 | !data->vmcoredd_callback || !data->size) | |
1498 | return -EINVAL; | |
1499 | ||
1500 | dump = vzalloc(sizeof(*dump)); | |
1501 | if (!dump) { | |
1502 | ret = -ENOMEM; | |
1503 | goto out_err; | |
1504 | } | |
1505 | ||
1506 | /* Keep size of the buffer page aligned so that it can be mmaped */ | |
1507 | data_size = roundup(sizeof(struct vmcoredd_header) + data->size, | |
1508 | PAGE_SIZE); | |
1509 | ||
1510 | /* Allocate buffer for driver's to write their dumps */ | |
1511 | buf = vmcore_alloc_buf(data_size); | |
1512 | if (!buf) { | |
1513 | ret = -ENOMEM; | |
1514 | goto out_err; | |
1515 | } | |
1516 | ||
1517 | vmcoredd_write_header(buf, data, data_size - | |
1518 | sizeof(struct vmcoredd_header)); | |
1519 | ||
1520 | /* Invoke the driver's dump collection routing */ | |
1521 | ret = data->vmcoredd_callback(data, buf + | |
1522 | sizeof(struct vmcoredd_header)); | |
1523 | if (ret) | |
1524 | goto out_err; | |
1525 | ||
1526 | dump->buf = buf; | |
1527 | dump->size = data_size; | |
1528 | ||
1529 | /* Add the dump to driver sysfs list */ | |
1530 | mutex_lock(&vmcoredd_mutex); | |
1531 | list_add_tail(&dump->list, &vmcoredd_list); | |
1532 | mutex_unlock(&vmcoredd_mutex); | |
1533 | ||
7efe48df | 1534 | vmcoredd_update_size(data_size); |
2724273e RL |
1535 | return 0; |
1536 | ||
1537 | out_err: | |
fb9bf048 YL |
1538 | vfree(buf); |
1539 | vfree(dump); | |
2724273e RL |
1540 | |
1541 | return ret; | |
1542 | } | |
1543 | EXPORT_SYMBOL(vmcore_add_device_dump); | |
1544 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
1545 | ||
1546 | /* Free all dumps in vmcore device dump list */ | |
1547 | static void vmcore_free_device_dumps(void) | |
1548 | { | |
1549 | #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP | |
1550 | mutex_lock(&vmcoredd_mutex); | |
1551 | while (!list_empty(&vmcoredd_list)) { | |
1552 | struct vmcoredd_node *dump; | |
1553 | ||
1554 | dump = list_first_entry(&vmcoredd_list, struct vmcoredd_node, | |
1555 | list); | |
1556 | list_del(&dump->list); | |
1557 | vfree(dump->buf); | |
1558 | vfree(dump); | |
1559 | } | |
1560 | mutex_unlock(&vmcoredd_mutex); | |
1561 | #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ | |
1562 | } | |
1563 | ||
666bfddb VG |
1564 | /* Init function for vmcore module. */ |
1565 | static int __init vmcore_init(void) | |
1566 | { | |
1567 | int rc = 0; | |
1568 | ||
be8a8d06 MH |
1569 | /* Allow architectures to allocate ELF header in 2nd kernel */ |
1570 | rc = elfcorehdr_alloc(&elfcorehdr_addr, &elfcorehdr_size); | |
1571 | if (rc) | |
1572 | return rc; | |
1573 | /* | |
1574 | * If elfcorehdr= has been passed in cmdline or created in 2nd kernel, | |
1575 | * then capture the dump. | |
1576 | */ | |
85a0ee34 | 1577 | if (!(is_vmcore_usable())) |
666bfddb VG |
1578 | return rc; |
1579 | rc = parse_crash_elf_headers(); | |
1580 | if (rc) { | |
87ebdc00 | 1581 | pr_warn("Kdump: vmcore not initialized\n"); |
666bfddb VG |
1582 | return rc; |
1583 | } | |
be8a8d06 MH |
1584 | elfcorehdr_free(elfcorehdr_addr); |
1585 | elfcorehdr_addr = ELFCORE_ADDR_ERR; | |
666bfddb | 1586 | |
97a32539 | 1587 | proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &vmcore_proc_ops); |
666bfddb VG |
1588 | if (proc_vmcore) |
1589 | proc_vmcore->size = vmcore_size; | |
1590 | return 0; | |
1591 | } | |
abaf3787 | 1592 | fs_initcall(vmcore_init); |
16257393 MS |
1593 | |
1594 | /* Cleanup function for vmcore module. */ | |
1595 | void vmcore_cleanup(void) | |
1596 | { | |
16257393 | 1597 | if (proc_vmcore) { |
a8ca16ea | 1598 | proc_remove(proc_vmcore); |
16257393 MS |
1599 | proc_vmcore = NULL; |
1600 | } | |
1601 | ||
1602 | /* clear the vmcore list. */ | |
593bc695 | 1603 | while (!list_empty(&vmcore_list)) { |
16257393 MS |
1604 | struct vmcore *m; |
1605 | ||
593bc695 | 1606 | m = list_first_entry(&vmcore_list, struct vmcore, list); |
16257393 MS |
1607 | list_del(&m->list); |
1608 | kfree(m); | |
1609 | } | |
f2bdacdd | 1610 | free_elfcorebuf(); |
2724273e RL |
1611 | |
1612 | /* clear vmcore device dump list */ | |
1613 | vmcore_free_device_dumps(); | |
16257393 | 1614 | } |