Root/
Source at commit be977234bfb4a6dca8a39e7c52165e4cd536ad71 created 12 years 9 months ago. By Lars-Peter Clausen, jz4740: Fix compile error | |
---|---|
1 | /* |
2 | * kexec.c - kexec system call |
3 | * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com> |
4 | * |
5 | * This source code is licensed under the GNU General Public License, |
6 | * Version 2. See the file COPYING for more details. |
7 | */ |
8 | |
9 | #include <linux/capability.h> |
10 | #include <linux/mm.h> |
11 | #include <linux/file.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/fs.h> |
14 | #include <linux/kexec.h> |
15 | #include <linux/mutex.h> |
16 | #include <linux/list.h> |
17 | #include <linux/highmem.h> |
18 | #include <linux/syscalls.h> |
19 | #include <linux/reboot.h> |
20 | #include <linux/ioport.h> |
21 | #include <linux/hardirq.h> |
22 | #include <linux/elf.h> |
23 | #include <linux/elfcore.h> |
24 | #include <generated/utsrelease.h> |
25 | #include <linux/utsname.h> |
26 | #include <linux/numa.h> |
27 | #include <linux/suspend.h> |
28 | #include <linux/device.h> |
29 | #include <linux/freezer.h> |
30 | #include <linux/pm.h> |
31 | #include <linux/cpu.h> |
32 | #include <linux/console.h> |
33 | #include <linux/vmalloc.h> |
34 | #include <linux/swap.h> |
35 | #include <linux/kmsg_dump.h> |
36 | #include <linux/syscore_ops.h> |
37 | |
38 | #include <asm/page.h> |
39 | #include <asm/uaccess.h> |
40 | #include <asm/io.h> |
41 | #include <asm/system.h> |
42 | #include <asm/sections.h> |
43 | |
44 | /* Per cpu memory for storing cpu states in case of system crash. */ |
45 | note_buf_t __percpu *crash_notes; |
46 | |
47 | /* vmcoreinfo stuff */ |
48 | static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES]; |
49 | u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; |
50 | size_t vmcoreinfo_size; |
51 | size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data); |
52 | |
53 | /* Location of the reserved area for the crash kernel */ |
54 | struct resource crashk_res = { |
55 | .name = "Crash kernel", |
56 | .start = 0, |
57 | .end = 0, |
58 | .flags = IORESOURCE_BUSY | IORESOURCE_MEM |
59 | }; |
60 | |
61 | int kexec_should_crash(struct task_struct *p) |
62 | { |
63 | if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops) |
64 | return 1; |
65 | return 0; |
66 | } |
67 | |
68 | /* |
69 | * When kexec transitions to the new kernel there is a one-to-one |
70 | * mapping between physical and virtual addresses. On processors |
71 | * where you can disable the MMU this is trivial, and easy. For |
72 | * others it is still a simple predictable page table to setup. |
73 | * |
74 | * In that environment kexec copies the new kernel to its final |
75 | * resting place. This means I can only support memory whose |
76 | * physical address can fit in an unsigned long. In particular |
77 | * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled. |
78 | * If the assembly stub has more restrictive requirements |
79 | * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be |
80 | * defined more restrictively in <asm/kexec.h>. |
81 | * |
82 | * The code for the transition from the current kernel to the |
83 | * the new kernel is placed in the control_code_buffer, whose size |
84 | * is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single |
85 | * page of memory is necessary, but some architectures require more. |
86 | * Because this memory must be identity mapped in the transition from |
87 | * virtual to physical addresses it must live in the range |
88 | * 0 - TASK_SIZE, as only the user space mappings are arbitrarily |
89 | * modifiable. |
90 | * |
91 | * The assembly stub in the control code buffer is passed a linked list |
92 | * of descriptor pages detailing the source pages of the new kernel, |
93 | * and the destination addresses of those source pages. As this data |
94 | * structure is not used in the context of the current OS, it must |
95 | * be self-contained. |
96 | * |
97 | * The code has been made to work with highmem pages and will use a |
98 | * destination page in its final resting place (if it happens |
99 | * to allocate it). The end product of this is that most of the |
100 | * physical address space, and most of RAM can be used. |
101 | * |
102 | * Future directions include: |
103 | * - allocating a page table with the control code buffer identity |
104 | * mapped, to simplify machine_kexec and make kexec_on_panic more |
105 | * reliable. |
106 | */ |
107 | |
108 | /* |
109 | * KIMAGE_NO_DEST is an impossible destination address..., for |
110 | * allocating pages whose destination address we do not care about. |
111 | */ |
112 | #define KIMAGE_NO_DEST (-1UL) |
113 | |
114 | static int kimage_is_destination_range(struct kimage *image, |
115 | unsigned long start, unsigned long end); |
116 | static struct page *kimage_alloc_page(struct kimage *image, |
117 | gfp_t gfp_mask, |
118 | unsigned long dest); |
119 | |
120 | static int do_kimage_alloc(struct kimage **rimage, unsigned long entry, |
121 | unsigned long nr_segments, |
122 | struct kexec_segment __user *segments) |
123 | { |
124 | size_t segment_bytes; |
125 | struct kimage *image; |
126 | unsigned long i; |
127 | int result; |
128 | |
129 | /* Allocate a controlling structure */ |
130 | result = -ENOMEM; |
131 | image = kzalloc(sizeof(*image), GFP_KERNEL); |
132 | if (!image) |
133 | goto out; |
134 | |
135 | image->head = 0; |
136 | image->entry = &image->head; |
137 | image->last_entry = &image->head; |
138 | image->control_page = ~0; /* By default this does not apply */ |
139 | image->start = entry; |
140 | image->type = KEXEC_TYPE_DEFAULT; |
141 | |
142 | /* Initialize the list of control pages */ |
143 | INIT_LIST_HEAD(&image->control_pages); |
144 | |
145 | /* Initialize the list of destination pages */ |
146 | INIT_LIST_HEAD(&image->dest_pages); |
147 | |
148 | /* Initialize the list of unusable pages */ |
149 | INIT_LIST_HEAD(&image->unuseable_pages); |
150 | |
151 | /* Read in the segments */ |
152 | image->nr_segments = nr_segments; |
153 | segment_bytes = nr_segments * sizeof(*segments); |
154 | result = copy_from_user(image->segment, segments, segment_bytes); |
155 | if (result) { |
156 | result = -EFAULT; |
157 | goto out; |
158 | } |
159 | |
160 | /* |
161 | * Verify we have good destination addresses. The caller is |
162 | * responsible for making certain we don't attempt to load |
163 | * the new image into invalid or reserved areas of RAM. This |
164 | * just verifies it is an address we can use. |
165 | * |
166 | * Since the kernel does everything in page size chunks ensure |
167 | * the destination addresses are page aligned. Too many |
168 | * special cases crop of when we don't do this. The most |
169 | * insidious is getting overlapping destination addresses |
170 | * simply because addresses are changed to page size |
171 | * granularity. |
172 | */ |
173 | result = -EADDRNOTAVAIL; |
174 | for (i = 0; i < nr_segments; i++) { |
175 | unsigned long mstart, mend; |
176 | |
177 | mstart = image->segment[i].mem; |
178 | mend = mstart + image->segment[i].memsz; |
179 | if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK)) |
180 | goto out; |
181 | if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT) |
182 | goto out; |
183 | } |
184 | |
185 | /* Verify our destination addresses do not overlap. |
186 | * If we alloed overlapping destination addresses |
187 | * through very weird things can happen with no |
188 | * easy explanation as one segment stops on another. |
189 | */ |
190 | result = -EINVAL; |
191 | for (i = 0; i < nr_segments; i++) { |
192 | unsigned long mstart, mend; |
193 | unsigned long j; |
194 | |
195 | mstart = image->segment[i].mem; |
196 | mend = mstart + image->segment[i].memsz; |
197 | for (j = 0; j < i; j++) { |
198 | unsigned long pstart, pend; |
199 | pstart = image->segment[j].mem; |
200 | pend = pstart + image->segment[j].memsz; |
201 | /* Do the segments overlap ? */ |
202 | if ((mend > pstart) && (mstart < pend)) |
203 | goto out; |
204 | } |
205 | } |
206 | |
207 | /* Ensure our buffer sizes are strictly less than |
208 | * our memory sizes. This should always be the case, |
209 | * and it is easier to check up front than to be surprised |
210 | * later on. |
211 | */ |
212 | result = -EINVAL; |
213 | for (i = 0; i < nr_segments; i++) { |
214 | if (image->segment[i].bufsz > image->segment[i].memsz) |
215 | goto out; |
216 | } |
217 | |
218 | result = 0; |
219 | out: |
220 | if (result == 0) |
221 | *rimage = image; |
222 | else |
223 | kfree(image); |
224 | |
225 | return result; |
226 | |
227 | } |
228 | |
229 | static int kimage_normal_alloc(struct kimage **rimage, unsigned long entry, |
230 | unsigned long nr_segments, |
231 | struct kexec_segment __user *segments) |
232 | { |
233 | int result; |
234 | struct kimage *image; |
235 | |
236 | /* Allocate and initialize a controlling structure */ |
237 | image = NULL; |
238 | result = do_kimage_alloc(&image, entry, nr_segments, segments); |
239 | if (result) |
240 | goto out; |
241 | |
242 | *rimage = image; |
243 | |
244 | /* |
245 | * Find a location for the control code buffer, and add it |
246 | * the vector of segments so that it's pages will also be |
247 | * counted as destination pages. |
248 | */ |
249 | result = -ENOMEM; |
250 | image->control_code_page = kimage_alloc_control_pages(image, |
251 | get_order(KEXEC_CONTROL_PAGE_SIZE)); |
252 | if (!image->control_code_page) { |
253 | printk(KERN_ERR "Could not allocate control_code_buffer\n"); |
254 | goto out; |
255 | } |
256 | |
257 | image->swap_page = kimage_alloc_control_pages(image, 0); |
258 | if (!image->swap_page) { |
259 | printk(KERN_ERR "Could not allocate swap buffer\n"); |
260 | goto out; |
261 | } |
262 | |
263 | result = 0; |
264 | out: |
265 | if (result == 0) |
266 | *rimage = image; |
267 | else |
268 | kfree(image); |
269 | |
270 | return result; |
271 | } |
272 | |
273 | static int kimage_crash_alloc(struct kimage **rimage, unsigned long entry, |
274 | unsigned long nr_segments, |
275 | struct kexec_segment __user *segments) |
276 | { |
277 | int result; |
278 | struct kimage *image; |
279 | unsigned long i; |
280 | |
281 | image = NULL; |
282 | /* Verify we have a valid entry point */ |
283 | if ((entry < crashk_res.start) || (entry > crashk_res.end)) { |
284 | result = -EADDRNOTAVAIL; |
285 | goto out; |
286 | } |
287 | |
288 | /* Allocate and initialize a controlling structure */ |
289 | result = do_kimage_alloc(&image, entry, nr_segments, segments); |
290 | if (result) |
291 | goto out; |
292 | |
293 | /* Enable the special crash kernel control page |
294 | * allocation policy. |
295 | */ |
296 | image->control_page = crashk_res.start; |
297 | image->type = KEXEC_TYPE_CRASH; |
298 | |
299 | /* |
300 | * Verify we have good destination addresses. Normally |
301 | * the caller is responsible for making certain we don't |
302 | * attempt to load the new image into invalid or reserved |
303 | * areas of RAM. But crash kernels are preloaded into a |
304 | * reserved area of ram. We must ensure the addresses |
305 | * are in the reserved area otherwise preloading the |
306 | * kernel could corrupt things. |
307 | */ |
308 | result = -EADDRNOTAVAIL; |
309 | for (i = 0; i < nr_segments; i++) { |
310 | unsigned long mstart, mend; |
311 | |
312 | mstart = image->segment[i].mem; |
313 | mend = mstart + image->segment[i].memsz - 1; |
314 | /* Ensure we are within the crash kernel limits */ |
315 | if ((mstart < crashk_res.start) || (mend > crashk_res.end)) |
316 | goto out; |
317 | } |
318 | |
319 | /* |
320 | * Find a location for the control code buffer, and add |
321 | * the vector of segments so that it's pages will also be |
322 | * counted as destination pages. |
323 | */ |
324 | result = -ENOMEM; |
325 | image->control_code_page = kimage_alloc_control_pages(image, |
326 | get_order(KEXEC_CONTROL_PAGE_SIZE)); |
327 | if (!image->control_code_page) { |
328 | printk(KERN_ERR "Could not allocate control_code_buffer\n"); |
329 | goto out; |
330 | } |
331 | |
332 | result = 0; |
333 | out: |
334 | if (result == 0) |
335 | *rimage = image; |
336 | else |
337 | kfree(image); |
338 | |
339 | return result; |
340 | } |
341 | |
342 | static int kimage_is_destination_range(struct kimage *image, |
343 | unsigned long start, |
344 | unsigned long end) |
345 | { |
346 | unsigned long i; |
347 | |
348 | for (i = 0; i < image->nr_segments; i++) { |
349 | unsigned long mstart, mend; |
350 | |
351 | mstart = image->segment[i].mem; |
352 | mend = mstart + image->segment[i].memsz; |
353 | if ((end > mstart) && (start < mend)) |
354 | return 1; |
355 | } |
356 | |
357 | return 0; |
358 | } |
359 | |
360 | static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order) |
361 | { |
362 | struct page *pages; |
363 | |
364 | pages = alloc_pages(gfp_mask, order); |
365 | if (pages) { |
366 | unsigned int count, i; |
367 | pages->mapping = NULL; |
368 | set_page_private(pages, order); |
369 | count = 1 << order; |
370 | for (i = 0; i < count; i++) |
371 | SetPageReserved(pages + i); |
372 | } |
373 | |
374 | return pages; |
375 | } |
376 | |
377 | static void kimage_free_pages(struct page *page) |
378 | { |
379 | unsigned int order, count, i; |
380 | |
381 | order = page_private(page); |
382 | count = 1 << order; |
383 | for (i = 0; i < count; i++) |
384 | ClearPageReserved(page + i); |
385 | __free_pages(page, order); |
386 | } |
387 | |
388 | static void kimage_free_page_list(struct list_head *list) |
389 | { |
390 | struct list_head *pos, *next; |
391 | |
392 | list_for_each_safe(pos, next, list) { |
393 | struct page *page; |
394 | |
395 | page = list_entry(pos, struct page, lru); |
396 | list_del(&page->lru); |
397 | kimage_free_pages(page); |
398 | } |
399 | } |
400 | |
401 | static struct page *kimage_alloc_normal_control_pages(struct kimage *image, |
402 | unsigned int order) |
403 | { |
404 | /* Control pages are special, they are the intermediaries |
405 | * that are needed while we copy the rest of the pages |
406 | * to their final resting place. As such they must |
407 | * not conflict with either the destination addresses |
408 | * or memory the kernel is already using. |
409 | * |
410 | * The only case where we really need more than one of |
411 | * these are for architectures where we cannot disable |
412 | * the MMU and must instead generate an identity mapped |
413 | * page table for all of the memory. |
414 | * |
415 | * At worst this runs in O(N) of the image size. |
416 | */ |
417 | struct list_head extra_pages; |
418 | struct page *pages; |
419 | unsigned int count; |
420 | |
421 | count = 1 << order; |
422 | INIT_LIST_HEAD(&extra_pages); |
423 | |
424 | /* Loop while I can allocate a page and the page allocated |
425 | * is a destination page. |
426 | */ |
427 | do { |
428 | unsigned long pfn, epfn, addr, eaddr; |
429 | |
430 | pages = kimage_alloc_pages(GFP_KERNEL, order); |
431 | if (!pages) |
432 | break; |
433 | pfn = page_to_pfn(pages); |
434 | epfn = pfn + count; |
435 | addr = pfn << PAGE_SHIFT; |
436 | eaddr = epfn << PAGE_SHIFT; |
437 | if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) || |
438 | kimage_is_destination_range(image, addr, eaddr)) { |
439 | list_add(&pages->lru, &extra_pages); |
440 | pages = NULL; |
441 | } |
442 | } while (!pages); |
443 | |
444 | if (pages) { |
445 | /* Remember the allocated page... */ |
446 | list_add(&pages->lru, &image->control_pages); |
447 | |
448 | /* Because the page is already in it's destination |
449 | * location we will never allocate another page at |
450 | * that address. Therefore kimage_alloc_pages |
451 | * will not return it (again) and we don't need |
452 | * to give it an entry in image->segment[]. |
453 | */ |
454 | } |
455 | /* Deal with the destination pages I have inadvertently allocated. |
456 | * |
457 | * Ideally I would convert multi-page allocations into single |
458 | * page allocations, and add everything to image->dest_pages. |
459 | * |
460 | * For now it is simpler to just free the pages. |
461 | */ |
462 | kimage_free_page_list(&extra_pages); |
463 | |
464 | return pages; |
465 | } |
466 | |
467 | static struct page *kimage_alloc_crash_control_pages(struct kimage *image, |
468 | unsigned int order) |
469 | { |
470 | /* Control pages are special, they are the intermediaries |
471 | * that are needed while we copy the rest of the pages |
472 | * to their final resting place. As such they must |
473 | * not conflict with either the destination addresses |
474 | * or memory the kernel is already using. |
475 | * |
476 | * Control pages are also the only pags we must allocate |
477 | * when loading a crash kernel. All of the other pages |
478 | * are specified by the segments and we just memcpy |
479 | * into them directly. |
480 | * |
481 | * The only case where we really need more than one of |
482 | * these are for architectures where we cannot disable |
483 | * the MMU and must instead generate an identity mapped |
484 | * page table for all of the memory. |
485 | * |
486 | * Given the low demand this implements a very simple |
487 | * allocator that finds the first hole of the appropriate |
488 | * size in the reserved memory region, and allocates all |
489 | * of the memory up to and including the hole. |
490 | */ |
491 | unsigned long hole_start, hole_end, size; |
492 | struct page *pages; |
493 | |
494 | pages = NULL; |
495 | size = (1 << order) << PAGE_SHIFT; |
496 | hole_start = (image->control_page + (size - 1)) & ~(size - 1); |
497 | hole_end = hole_start + size - 1; |
498 | while (hole_end <= crashk_res.end) { |
499 | unsigned long i; |
500 | |
501 | if (hole_end > KEXEC_CONTROL_MEMORY_LIMIT) |
502 | break; |
503 | if (hole_end > crashk_res.end) |
504 | break; |
505 | /* See if I overlap any of the segments */ |
506 | for (i = 0; i < image->nr_segments; i++) { |
507 | unsigned long mstart, mend; |
508 | |
509 | mstart = image->segment[i].mem; |
510 | mend = mstart + image->segment[i].memsz - 1; |
511 | if ((hole_end >= mstart) && (hole_start <= mend)) { |
512 | /* Advance the hole to the end of the segment */ |
513 | hole_start = (mend + (size - 1)) & ~(size - 1); |
514 | hole_end = hole_start + size - 1; |
515 | break; |
516 | } |
517 | } |
518 | /* If I don't overlap any segments I have found my hole! */ |
519 | if (i == image->nr_segments) { |
520 | pages = pfn_to_page(hole_start >> PAGE_SHIFT); |
521 | break; |
522 | } |
523 | } |
524 | if (pages) |
525 | image->control_page = hole_end; |
526 | |
527 | return pages; |
528 | } |
529 | |
530 | |
531 | struct page *kimage_alloc_control_pages(struct kimage *image, |
532 | unsigned int order) |
533 | { |
534 | struct page *pages = NULL; |
535 | |
536 | switch (image->type) { |
537 | case KEXEC_TYPE_DEFAULT: |
538 | pages = kimage_alloc_normal_control_pages(image, order); |
539 | break; |
540 | case KEXEC_TYPE_CRASH: |
541 | pages = kimage_alloc_crash_control_pages(image, order); |
542 | break; |
543 | } |
544 | |
545 | return pages; |
546 | } |
547 | |
548 | static int kimage_add_entry(struct kimage *image, kimage_entry_t entry) |
549 | { |
550 | if (*image->entry != 0) |
551 | image->entry++; |
552 | |
553 | if (image->entry == image->last_entry) { |
554 | kimage_entry_t *ind_page; |
555 | struct page *page; |
556 | |
557 | page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST); |
558 | if (!page) |
559 | return -ENOMEM; |
560 | |
561 | ind_page = page_address(page); |
562 | *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION; |
563 | image->entry = ind_page; |
564 | image->last_entry = ind_page + |
565 | ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1); |
566 | } |
567 | *image->entry = entry; |
568 | image->entry++; |
569 | *image->entry = 0; |
570 | |
571 | return 0; |
572 | } |
573 | |
574 | static int kimage_set_destination(struct kimage *image, |
575 | unsigned long destination) |
576 | { |
577 | int result; |
578 | |
579 | destination &= PAGE_MASK; |
580 | result = kimage_add_entry(image, destination | IND_DESTINATION); |
581 | if (result == 0) |
582 | image->destination = destination; |
583 | |
584 | return result; |
585 | } |
586 | |
587 | |
588 | static int kimage_add_page(struct kimage *image, unsigned long page) |
589 | { |
590 | int result; |
591 | |
592 | page &= PAGE_MASK; |
593 | result = kimage_add_entry(image, page | IND_SOURCE); |
594 | if (result == 0) |
595 | image->destination += PAGE_SIZE; |
596 | |
597 | return result; |
598 | } |
599 | |
600 | |
601 | static void kimage_free_extra_pages(struct kimage *image) |
602 | { |
603 | /* Walk through and free any extra destination pages I may have */ |
604 | kimage_free_page_list(&image->dest_pages); |
605 | |
606 | /* Walk through and free any unusable pages I have cached */ |
607 | kimage_free_page_list(&image->unuseable_pages); |
608 | |
609 | } |
610 | static void kimage_terminate(struct kimage *image) |
611 | { |
612 | if (*image->entry != 0) |
613 | image->entry++; |
614 | |
615 | *image->entry = IND_DONE; |
616 | } |
617 | |
618 | #define for_each_kimage_entry(image, ptr, entry) \ |
619 | for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \ |
620 | ptr = (entry & IND_INDIRECTION)? \ |
621 | phys_to_virt((entry & PAGE_MASK)): ptr +1) |
622 | |
623 | static void kimage_free_entry(kimage_entry_t entry) |
624 | { |
625 | struct page *page; |
626 | |
627 | page = pfn_to_page(entry >> PAGE_SHIFT); |
628 | kimage_free_pages(page); |
629 | } |
630 | |
631 | static void kimage_free(struct kimage *image) |
632 | { |
633 | kimage_entry_t *ptr, entry; |
634 | kimage_entry_t ind = 0; |
635 | |
636 | if (!image) |
637 | return; |
638 | |
639 | kimage_free_extra_pages(image); |
640 | for_each_kimage_entry(image, ptr, entry) { |
641 | if (entry & IND_INDIRECTION) { |
642 | /* Free the previous indirection page */ |
643 | if (ind & IND_INDIRECTION) |
644 | kimage_free_entry(ind); |
645 | /* Save this indirection page until we are |
646 | * done with it. |
647 | */ |
648 | ind = entry; |
649 | } |
650 | else if (entry & IND_SOURCE) |
651 | kimage_free_entry(entry); |
652 | } |
653 | /* Free the final indirection page */ |
654 | if (ind & IND_INDIRECTION) |
655 | kimage_free_entry(ind); |
656 | |
657 | /* Handle any machine specific cleanup */ |
658 | machine_kexec_cleanup(image); |
659 | |
660 | /* Free the kexec control pages... */ |
661 | kimage_free_page_list(&image->control_pages); |
662 | kfree(image); |
663 | } |
664 | |
665 | static kimage_entry_t *kimage_dst_used(struct kimage *image, |
666 | unsigned long page) |
667 | { |
668 | kimage_entry_t *ptr, entry; |
669 | unsigned long destination = 0; |
670 | |
671 | for_each_kimage_entry(image, ptr, entry) { |
672 | if (entry & IND_DESTINATION) |
673 | destination = entry & PAGE_MASK; |
674 | else if (entry & IND_SOURCE) { |
675 | if (page == destination) |
676 | return ptr; |
677 | destination += PAGE_SIZE; |
678 | } |
679 | } |
680 | |
681 | return NULL; |
682 | } |
683 | |
684 | static struct page *kimage_alloc_page(struct kimage *image, |
685 | gfp_t gfp_mask, |
686 | unsigned long destination) |
687 | { |
688 | /* |
689 | * Here we implement safeguards to ensure that a source page |
690 | * is not copied to its destination page before the data on |
691 | * the destination page is no longer useful. |
692 | * |
693 | * To do this we maintain the invariant that a source page is |
694 | * either its own destination page, or it is not a |
695 | * destination page at all. |
696 | * |
697 | * That is slightly stronger than required, but the proof |
698 | * that no problems will not occur is trivial, and the |
699 | * implementation is simply to verify. |
700 | * |
701 | * When allocating all pages normally this algorithm will run |
702 | * in O(N) time, but in the worst case it will run in O(N^2) |
703 | * time. If the runtime is a problem the data structures can |
704 | * be fixed. |
705 | */ |
706 | struct page *page; |
707 | unsigned long addr; |
708 | |
709 | /* |
710 | * Walk through the list of destination pages, and see if I |
711 | * have a match. |
712 | */ |
713 | list_for_each_entry(page, &image->dest_pages, lru) { |
714 | addr = page_to_pfn(page) << PAGE_SHIFT; |
715 | if (addr == destination) { |
716 | list_del(&page->lru); |
717 | return page; |
718 | } |
719 | } |
720 | page = NULL; |
721 | while (1) { |
722 | kimage_entry_t *old; |
723 | |
724 | /* Allocate a page, if we run out of memory give up */ |
725 | page = kimage_alloc_pages(gfp_mask, 0); |
726 | if (!page) |
727 | return NULL; |
728 | /* If the page cannot be used file it away */ |
729 | if (page_to_pfn(page) > |
730 | (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) { |
731 | list_add(&page->lru, &image->unuseable_pages); |
732 | continue; |
733 | } |
734 | addr = page_to_pfn(page) << PAGE_SHIFT; |
735 | |
736 | /* If it is the destination page we want use it */ |
737 | if (addr == destination) |
738 | break; |
739 | |
740 | /* If the page is not a destination page use it */ |
741 | if (!kimage_is_destination_range(image, addr, |
742 | addr + PAGE_SIZE)) |
743 | break; |
744 | |
745 | /* |
746 | * I know that the page is someones destination page. |
747 | * See if there is already a source page for this |
748 | * destination page. And if so swap the source pages. |
749 | */ |
750 | old = kimage_dst_used(image, addr); |
751 | if (old) { |
752 | /* If so move it */ |
753 | unsigned long old_addr; |
754 | struct page *old_page; |
755 | |
756 | old_addr = *old & PAGE_MASK; |
757 | old_page = pfn_to_page(old_addr >> PAGE_SHIFT); |
758 | copy_highpage(page, old_page); |
759 | *old = addr | (*old & ~PAGE_MASK); |
760 | |
761 | /* The old page I have found cannot be a |
762 | * destination page, so return it if it's |
763 | * gfp_flags honor the ones passed in. |
764 | */ |
765 | if (!(gfp_mask & __GFP_HIGHMEM) && |
766 | PageHighMem(old_page)) { |
767 | kimage_free_pages(old_page); |
768 | continue; |
769 | } |
770 | addr = old_addr; |
771 | page = old_page; |
772 | break; |
773 | } |
774 | else { |
775 | /* Place the page on the destination list I |
776 | * will use it later. |
777 | */ |
778 | list_add(&page->lru, &image->dest_pages); |
779 | } |
780 | } |
781 | |
782 | return page; |
783 | } |
784 | |
785 | static int kimage_load_normal_segment(struct kimage *image, |
786 | struct kexec_segment *segment) |
787 | { |
788 | unsigned long maddr; |
789 | unsigned long ubytes, mbytes; |
790 | int result; |
791 | unsigned char __user *buf; |
792 | |
793 | result = 0; |
794 | buf = segment->buf; |
795 | ubytes = segment->bufsz; |
796 | mbytes = segment->memsz; |
797 | maddr = segment->mem; |
798 | |
799 | result = kimage_set_destination(image, maddr); |
800 | if (result < 0) |
801 | goto out; |
802 | |
803 | while (mbytes) { |
804 | struct page *page; |
805 | char *ptr; |
806 | size_t uchunk, mchunk; |
807 | |
808 | page = kimage_alloc_page(image, GFP_HIGHUSER, maddr); |
809 | if (!page) { |
810 | result = -ENOMEM; |
811 | goto out; |
812 | } |
813 | result = kimage_add_page(image, page_to_pfn(page) |
814 | << PAGE_SHIFT); |
815 | if (result < 0) |
816 | goto out; |
817 | |
818 | ptr = kmap(page); |
819 | /* Start with a clear page */ |
820 | clear_page(ptr); |
821 | ptr += maddr & ~PAGE_MASK; |
822 | mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK); |
823 | if (mchunk > mbytes) |
824 | mchunk = mbytes; |
825 | |
826 | uchunk = mchunk; |
827 | if (uchunk > ubytes) |
828 | uchunk = ubytes; |
829 | |
830 | result = copy_from_user(ptr, buf, uchunk); |
831 | kunmap(page); |
832 | if (result) { |
833 | result = -EFAULT; |
834 | goto out; |
835 | } |
836 | ubytes -= uchunk; |
837 | maddr += mchunk; |
838 | buf += mchunk; |
839 | mbytes -= mchunk; |
840 | } |
841 | out: |
842 | return result; |
843 | } |
844 | |
845 | static int kimage_load_crash_segment(struct kimage *image, |
846 | struct kexec_segment *segment) |
847 | { |
848 | /* For crash dumps kernels we simply copy the data from |
849 | * user space to it's destination. |
850 | * We do things a page at a time for the sake of kmap. |
851 | */ |
852 | unsigned long maddr; |
853 | unsigned long ubytes, mbytes; |
854 | int result; |
855 | unsigned char __user *buf; |
856 | |
857 | result = 0; |
858 | buf = segment->buf; |
859 | ubytes = segment->bufsz; |
860 | mbytes = segment->memsz; |
861 | maddr = segment->mem; |
862 | while (mbytes) { |
863 | struct page *page; |
864 | char *ptr; |
865 | size_t uchunk, mchunk; |
866 | |
867 | page = pfn_to_page(maddr >> PAGE_SHIFT); |
868 | if (!page) { |
869 | result = -ENOMEM; |
870 | goto out; |
871 | } |
872 | ptr = kmap(page); |
873 | ptr += maddr & ~PAGE_MASK; |
874 | mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK); |
875 | if (mchunk > mbytes) |
876 | mchunk = mbytes; |
877 | |
878 | uchunk = mchunk; |
879 | if (uchunk > ubytes) { |
880 | uchunk = ubytes; |
881 | /* Zero the trailing part of the page */ |
882 | memset(ptr + uchunk, 0, mchunk - uchunk); |
883 | } |
884 | result = copy_from_user(ptr, buf, uchunk); |
885 | kexec_flush_icache_page(page); |
886 | kunmap(page); |
887 | if (result) { |
888 | result = -EFAULT; |
889 | goto out; |
890 | } |
891 | ubytes -= uchunk; |
892 | maddr += mchunk; |
893 | buf += mchunk; |
894 | mbytes -= mchunk; |
895 | } |
896 | out: |
897 | return result; |
898 | } |
899 | |
900 | static int kimage_load_segment(struct kimage *image, |
901 | struct kexec_segment *segment) |
902 | { |
903 | int result = -ENOMEM; |
904 | |
905 | switch (image->type) { |
906 | case KEXEC_TYPE_DEFAULT: |
907 | result = kimage_load_normal_segment(image, segment); |
908 | break; |
909 | case KEXEC_TYPE_CRASH: |
910 | result = kimage_load_crash_segment(image, segment); |
911 | break; |
912 | } |
913 | |
914 | return result; |
915 | } |
916 | |
917 | /* |
918 | * Exec Kernel system call: for obvious reasons only root may call it. |
919 | * |
920 | * This call breaks up into three pieces. |
921 | * - A generic part which loads the new kernel from the current |
922 | * address space, and very carefully places the data in the |
923 | * allocated pages. |
924 | * |
925 | * - A generic part that interacts with the kernel and tells all of |
926 | * the devices to shut down. Preventing on-going dmas, and placing |
927 | * the devices in a consistent state so a later kernel can |
928 | * reinitialize them. |
929 | * |
930 | * - A machine specific part that includes the syscall number |
931 | * and the copies the image to it's final destination. And |
932 | * jumps into the image at entry. |
933 | * |
934 | * kexec does not sync, or unmount filesystems so if you need |
935 | * that to happen you need to do that yourself. |
936 | */ |
937 | struct kimage *kexec_image; |
938 | struct kimage *kexec_crash_image; |
939 | |
940 | static DEFINE_MUTEX(kexec_mutex); |
941 | |
942 | SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, |
943 | struct kexec_segment __user *, segments, unsigned long, flags) |
944 | { |
945 | struct kimage **dest_image, *image; |
946 | int result; |
947 | |
948 | /* We only trust the superuser with rebooting the system. */ |
949 | if (!capable(CAP_SYS_BOOT)) |
950 | return -EPERM; |
951 | |
952 | /* |
953 | * Verify we have a legal set of flags |
954 | * This leaves us room for future extensions. |
955 | */ |
956 | if ((flags & KEXEC_FLAGS) != (flags & ~KEXEC_ARCH_MASK)) |
957 | return -EINVAL; |
958 | |
959 | /* Verify we are on the appropriate architecture */ |
960 | if (((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH) && |
961 | ((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT)) |
962 | return -EINVAL; |
963 | |
964 | /* Put an artificial cap on the number |
965 | * of segments passed to kexec_load. |
966 | */ |
967 | if (nr_segments > KEXEC_SEGMENT_MAX) |
968 | return -EINVAL; |
969 | |
970 | image = NULL; |
971 | result = 0; |
972 | |
973 | /* Because we write directly to the reserved memory |
974 | * region when loading crash kernels we need a mutex here to |
975 | * prevent multiple crash kernels from attempting to load |
976 | * simultaneously, and to prevent a crash kernel from loading |
977 | * over the top of a in use crash kernel. |
978 | * |
979 | * KISS: always take the mutex. |
980 | */ |
981 | if (!mutex_trylock(&kexec_mutex)) |
982 | return -EBUSY; |
983 | |
984 | dest_image = &kexec_image; |
985 | if (flags & KEXEC_ON_CRASH) |
986 | dest_image = &kexec_crash_image; |
987 | if (nr_segments > 0) { |
988 | unsigned long i; |
989 | |
990 | /* Loading another kernel to reboot into */ |
991 | if ((flags & KEXEC_ON_CRASH) == 0) |
992 | result = kimage_normal_alloc(&image, entry, |
993 | nr_segments, segments); |
994 | /* Loading another kernel to switch to if this one crashes */ |
995 | else if (flags & KEXEC_ON_CRASH) { |
996 | /* Free any current crash dump kernel before |
997 | * we corrupt it. |
998 | */ |
999 | kimage_free(xchg(&kexec_crash_image, NULL)); |
1000 | result = kimage_crash_alloc(&image, entry, |
1001 | nr_segments, segments); |
1002 | } |
1003 | if (result) |
1004 | goto out; |
1005 | |
1006 | if (flags & KEXEC_PRESERVE_CONTEXT) |
1007 | image->preserve_context = 1; |
1008 | result = machine_kexec_prepare(image); |
1009 | if (result) |
1010 | goto out; |
1011 | |
1012 | for (i = 0; i < nr_segments; i++) { |
1013 | result = kimage_load_segment(image, &image->segment[i]); |
1014 | if (result) |
1015 | goto out; |
1016 | } |
1017 | kimage_terminate(image); |
1018 | } |
1019 | /* Install the new kernel, and Uninstall the old */ |
1020 | image = xchg(dest_image, image); |
1021 | |
1022 | out: |
1023 | mutex_unlock(&kexec_mutex); |
1024 | kimage_free(image); |
1025 | |
1026 | return result; |
1027 | } |
1028 | |
1029 | #ifdef CONFIG_COMPAT |
1030 | asmlinkage long compat_sys_kexec_load(unsigned long entry, |
1031 | unsigned long nr_segments, |
1032 | struct compat_kexec_segment __user *segments, |
1033 | unsigned long flags) |
1034 | { |
1035 | struct compat_kexec_segment in; |
1036 | struct kexec_segment out, __user *ksegments; |
1037 | unsigned long i, result; |
1038 | |
1039 | /* Don't allow clients that don't understand the native |
1040 | * architecture to do anything. |
1041 | */ |
1042 | if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT) |
1043 | return -EINVAL; |
1044 | |
1045 | if (nr_segments > KEXEC_SEGMENT_MAX) |
1046 | return -EINVAL; |
1047 | |
1048 | ksegments = compat_alloc_user_space(nr_segments * sizeof(out)); |
1049 | for (i=0; i < nr_segments; i++) { |
1050 | result = copy_from_user(&in, &segments[i], sizeof(in)); |
1051 | if (result) |
1052 | return -EFAULT; |
1053 | |
1054 | out.buf = compat_ptr(in.buf); |
1055 | out.bufsz = in.bufsz; |
1056 | out.mem = in.mem; |
1057 | out.memsz = in.memsz; |
1058 | |
1059 | result = copy_to_user(&ksegments[i], &out, sizeof(out)); |
1060 | if (result) |
1061 | return -EFAULT; |
1062 | } |
1063 | |
1064 | return sys_kexec_load(entry, nr_segments, ksegments, flags); |
1065 | } |
1066 | #endif |
1067 | |
1068 | void crash_kexec(struct pt_regs *regs) |
1069 | { |
1070 | /* Take the kexec_mutex here to prevent sys_kexec_load |
1071 | * running on one cpu from replacing the crash kernel |
1072 | * we are using after a panic on a different cpu. |
1073 | * |
1074 | * If the crash kernel was not located in a fixed area |
1075 | * of memory the xchg(&kexec_crash_image) would be |
1076 | * sufficient. But since I reuse the memory... |
1077 | */ |
1078 | if (mutex_trylock(&kexec_mutex)) { |
1079 | if (kexec_crash_image) { |
1080 | struct pt_regs fixed_regs; |
1081 | |
1082 | kmsg_dump(KMSG_DUMP_KEXEC); |
1083 | |
1084 | crash_setup_regs(&fixed_regs, regs); |
1085 | crash_save_vmcoreinfo(); |
1086 | machine_crash_shutdown(&fixed_regs); |
1087 | machine_kexec(kexec_crash_image); |
1088 | } |
1089 | mutex_unlock(&kexec_mutex); |
1090 | } |
1091 | } |
1092 | |
1093 | size_t crash_get_memory_size(void) |
1094 | { |
1095 | size_t size = 0; |
1096 | mutex_lock(&kexec_mutex); |
1097 | if (crashk_res.end != crashk_res.start) |
1098 | size = crashk_res.end - crashk_res.start + 1; |
1099 | mutex_unlock(&kexec_mutex); |
1100 | return size; |
1101 | } |
1102 | |
1103 | void __weak crash_free_reserved_phys_range(unsigned long begin, |
1104 | unsigned long end) |
1105 | { |
1106 | unsigned long addr; |
1107 | |
1108 | for (addr = begin; addr < end; addr += PAGE_SIZE) { |
1109 | ClearPageReserved(pfn_to_page(addr >> PAGE_SHIFT)); |
1110 | init_page_count(pfn_to_page(addr >> PAGE_SHIFT)); |
1111 | free_page((unsigned long)__va(addr)); |
1112 | totalram_pages++; |
1113 | } |
1114 | } |
1115 | |
1116 | int crash_shrink_memory(unsigned long new_size) |
1117 | { |
1118 | int ret = 0; |
1119 | unsigned long start, end; |
1120 | |
1121 | mutex_lock(&kexec_mutex); |
1122 | |
1123 | if (kexec_crash_image) { |
1124 | ret = -ENOENT; |
1125 | goto unlock; |
1126 | } |
1127 | start = crashk_res.start; |
1128 | end = crashk_res.end; |
1129 | |
1130 | if (new_size >= end - start + 1) { |
1131 | ret = -EINVAL; |
1132 | if (new_size == end - start + 1) |
1133 | ret = 0; |
1134 | goto unlock; |
1135 | } |
1136 | |
1137 | start = roundup(start, PAGE_SIZE); |
1138 | end = roundup(start + new_size, PAGE_SIZE); |
1139 | |
1140 | crash_free_reserved_phys_range(end, crashk_res.end); |
1141 | |
1142 | if ((start == end) && (crashk_res.parent != NULL)) |
1143 | release_resource(&crashk_res); |
1144 | crashk_res.end = end - 1; |
1145 | |
1146 | unlock: |
1147 | mutex_unlock(&kexec_mutex); |
1148 | return ret; |
1149 | } |
1150 | |
1151 | static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data, |
1152 | size_t data_len) |
1153 | { |
1154 | struct elf_note note; |
1155 | |
1156 | note.n_namesz = strlen(name) + 1; |
1157 | note.n_descsz = data_len; |
1158 | note.n_type = type; |
1159 | memcpy(buf, ¬e, sizeof(note)); |
1160 | buf += (sizeof(note) + 3)/4; |
1161 | memcpy(buf, name, note.n_namesz); |
1162 | buf += (note.n_namesz + 3)/4; |
1163 | memcpy(buf, data, note.n_descsz); |
1164 | buf += (note.n_descsz + 3)/4; |
1165 | |
1166 | return buf; |
1167 | } |
1168 | |
1169 | static void final_note(u32 *buf) |
1170 | { |
1171 | struct elf_note note; |
1172 | |
1173 | note.n_namesz = 0; |
1174 | note.n_descsz = 0; |
1175 | note.n_type = 0; |
1176 | memcpy(buf, ¬e, sizeof(note)); |
1177 | } |
1178 | |
1179 | void crash_save_cpu(struct pt_regs *regs, int cpu) |
1180 | { |
1181 | struct elf_prstatus prstatus; |
1182 | u32 *buf; |
1183 | |
1184 | if ((cpu < 0) || (cpu >= nr_cpu_ids)) |
1185 | return; |
1186 | |
1187 | /* Using ELF notes here is opportunistic. |
1188 | * I need a well defined structure format |
1189 | * for the data I pass, and I need tags |
1190 | * on the data to indicate what information I have |
1191 | * squirrelled away. ELF notes happen to provide |
1192 | * all of that, so there is no need to invent something new. |
1193 | */ |
1194 | buf = (u32*)per_cpu_ptr(crash_notes, cpu); |
1195 | if (!buf) |
1196 | return; |
1197 | memset(&prstatus, 0, sizeof(prstatus)); |
1198 | prstatus.pr_pid = current->pid; |
1199 | elf_core_copy_kernel_regs(&prstatus.pr_reg, regs); |
1200 | buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS, |
1201 | &prstatus, sizeof(prstatus)); |
1202 | final_note(buf); |
1203 | } |
1204 | |
1205 | static int __init crash_notes_memory_init(void) |
1206 | { |
1207 | /* Allocate memory for saving cpu registers. */ |
1208 | crash_notes = alloc_percpu(note_buf_t); |
1209 | if (!crash_notes) { |
1210 | printk("Kexec: Memory allocation for saving cpu register" |
1211 | " states failed\n"); |
1212 | return -ENOMEM; |
1213 | } |
1214 | return 0; |
1215 | } |
1216 | module_init(crash_notes_memory_init) |
1217 | |
1218 | |
1219 | /* |
1220 | * parsing the "crashkernel" commandline |
1221 | * |
1222 | * this code is intended to be called from architecture specific code |
1223 | */ |
1224 | |
1225 | |
1226 | /* |
1227 | * This function parses command lines in the format |
1228 | * |
1229 | * crashkernel=ramsize-range:size[,...][@offset] |
1230 | * |
1231 | * The function returns 0 on success and -EINVAL on failure. |
1232 | */ |
1233 | static int __init parse_crashkernel_mem(char *cmdline, |
1234 | unsigned long long system_ram, |
1235 | unsigned long long *crash_size, |
1236 | unsigned long long *crash_base) |
1237 | { |
1238 | char *cur = cmdline, *tmp; |
1239 | |
1240 | /* for each entry of the comma-separated list */ |
1241 | do { |
1242 | unsigned long long start, end = ULLONG_MAX, size; |
1243 | |
1244 | /* get the start of the range */ |
1245 | start = memparse(cur, &tmp); |
1246 | if (cur == tmp) { |
1247 | pr_warning("crashkernel: Memory value expected\n"); |
1248 | return -EINVAL; |
1249 | } |
1250 | cur = tmp; |
1251 | if (*cur != '-') { |
1252 | pr_warning("crashkernel: '-' expected\n"); |
1253 | return -EINVAL; |
1254 | } |
1255 | cur++; |
1256 | |
1257 | /* if no ':' is here, than we read the end */ |
1258 | if (*cur != ':') { |
1259 | end = memparse(cur, &tmp); |
1260 | if (cur == tmp) { |
1261 | pr_warning("crashkernel: Memory " |
1262 | "value expected\n"); |
1263 | return -EINVAL; |
1264 | } |
1265 | cur = tmp; |
1266 | if (end <= start) { |
1267 | pr_warning("crashkernel: end <= start\n"); |
1268 | return -EINVAL; |
1269 | } |
1270 | } |
1271 | |
1272 | if (*cur != ':') { |
1273 | pr_warning("crashkernel: ':' expected\n"); |
1274 | return -EINVAL; |
1275 | } |
1276 | cur++; |
1277 | |
1278 | size = memparse(cur, &tmp); |
1279 | if (cur == tmp) { |
1280 | pr_warning("Memory value expected\n"); |
1281 | return -EINVAL; |
1282 | } |
1283 | cur = tmp; |
1284 | if (size >= system_ram) { |
1285 | pr_warning("crashkernel: invalid size\n"); |
1286 | return -EINVAL; |
1287 | } |
1288 | |
1289 | /* match ? */ |
1290 | if (system_ram >= start && system_ram < end) { |
1291 | *crash_size = size; |
1292 | break; |
1293 | } |
1294 | } while (*cur++ == ','); |
1295 | |
1296 | if (*crash_size > 0) { |
1297 | while (*cur && *cur != ' ' && *cur != '@') |
1298 | cur++; |
1299 | if (*cur == '@') { |
1300 | cur++; |
1301 | *crash_base = memparse(cur, &tmp); |
1302 | if (cur == tmp) { |
1303 | pr_warning("Memory value expected " |
1304 | "after '@'\n"); |
1305 | return -EINVAL; |
1306 | } |
1307 | } |
1308 | } |
1309 | |
1310 | return 0; |
1311 | } |
1312 | |
1313 | /* |
1314 | * That function parses "simple" (old) crashkernel command lines like |
1315 | * |
1316 | * crashkernel=size[@offset] |
1317 | * |
1318 | * It returns 0 on success and -EINVAL on failure. |
1319 | */ |
1320 | static int __init parse_crashkernel_simple(char *cmdline, |
1321 | unsigned long long *crash_size, |
1322 | unsigned long long *crash_base) |
1323 | { |
1324 | char *cur = cmdline; |
1325 | |
1326 | *crash_size = memparse(cmdline, &cur); |
1327 | if (cmdline == cur) { |
1328 | pr_warning("crashkernel: memory value expected\n"); |
1329 | return -EINVAL; |
1330 | } |
1331 | |
1332 | if (*cur == '@') |
1333 | *crash_base = memparse(cur+1, &cur); |
1334 | |
1335 | return 0; |
1336 | } |
1337 | |
1338 | /* |
1339 | * That function is the entry point for command line parsing and should be |
1340 | * called from the arch-specific code. |
1341 | */ |
1342 | int __init parse_crashkernel(char *cmdline, |
1343 | unsigned long long system_ram, |
1344 | unsigned long long *crash_size, |
1345 | unsigned long long *crash_base) |
1346 | { |
1347 | char *p = cmdline, *ck_cmdline = NULL; |
1348 | char *first_colon, *first_space; |
1349 | |
1350 | BUG_ON(!crash_size || !crash_base); |
1351 | *crash_size = 0; |
1352 | *crash_base = 0; |
1353 | |
1354 | /* find crashkernel and use the last one if there are more */ |
1355 | p = strstr(p, "crashkernel="); |
1356 | while (p) { |
1357 | ck_cmdline = p; |
1358 | p = strstr(p+1, "crashkernel="); |
1359 | } |
1360 | |
1361 | if (!ck_cmdline) |
1362 | return -EINVAL; |
1363 | |
1364 | ck_cmdline += 12; /* strlen("crashkernel=") */ |
1365 | |
1366 | /* |
1367 | * if the commandline contains a ':', then that's the extended |
1368 | * syntax -- if not, it must be the classic syntax |
1369 | */ |
1370 | first_colon = strchr(ck_cmdline, ':'); |
1371 | first_space = strchr(ck_cmdline, ' '); |
1372 | if (first_colon && (!first_space || first_colon < first_space)) |
1373 | return parse_crashkernel_mem(ck_cmdline, system_ram, |
1374 | crash_size, crash_base); |
1375 | else |
1376 | return parse_crashkernel_simple(ck_cmdline, crash_size, |
1377 | crash_base); |
1378 | |
1379 | return 0; |
1380 | } |
1381 | |
1382 | |
1383 | |
1384 | void crash_save_vmcoreinfo(void) |
1385 | { |
1386 | u32 *buf; |
1387 | |
1388 | if (!vmcoreinfo_size) |
1389 | return; |
1390 | |
1391 | vmcoreinfo_append_str("CRASHTIME=%ld", get_seconds()); |
1392 | |
1393 | buf = (u32 *)vmcoreinfo_note; |
1394 | |
1395 | buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, |
1396 | vmcoreinfo_size); |
1397 | |
1398 | final_note(buf); |
1399 | } |
1400 | |
1401 | void vmcoreinfo_append_str(const char *fmt, ...) |
1402 | { |
1403 | va_list args; |
1404 | char buf[0x50]; |
1405 | int r; |
1406 | |
1407 | va_start(args, fmt); |
1408 | r = vsnprintf(buf, sizeof(buf), fmt, args); |
1409 | va_end(args); |
1410 | |
1411 | if (r + vmcoreinfo_size > vmcoreinfo_max_size) |
1412 | r = vmcoreinfo_max_size - vmcoreinfo_size; |
1413 | |
1414 | memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r); |
1415 | |
1416 | vmcoreinfo_size += r; |
1417 | } |
1418 | |
1419 | /* |
1420 | * provide an empty default implementation here -- architecture |
1421 | * code may override this |
1422 | */ |
1423 | void __attribute__ ((weak)) arch_crash_save_vmcoreinfo(void) |
1424 | {} |
1425 | |
1426 | unsigned long __attribute__ ((weak)) paddr_vmcoreinfo_note(void) |
1427 | { |
1428 | return __pa((unsigned long)(char *)&vmcoreinfo_note); |
1429 | } |
1430 | |
1431 | static int __init crash_save_vmcoreinfo_init(void) |
1432 | { |
1433 | VMCOREINFO_OSRELEASE(init_uts_ns.name.release); |
1434 | VMCOREINFO_PAGESIZE(PAGE_SIZE); |
1435 | |
1436 | VMCOREINFO_SYMBOL(init_uts_ns); |
1437 | VMCOREINFO_SYMBOL(node_online_map); |
1438 | VMCOREINFO_SYMBOL(swapper_pg_dir); |
1439 | VMCOREINFO_SYMBOL(_stext); |
1440 | VMCOREINFO_SYMBOL(vmlist); |
1441 | |
1442 | #ifndef CONFIG_NEED_MULTIPLE_NODES |
1443 | VMCOREINFO_SYMBOL(mem_map); |
1444 | VMCOREINFO_SYMBOL(contig_page_data); |
1445 | #endif |
1446 | #ifdef CONFIG_SPARSEMEM |
1447 | VMCOREINFO_SYMBOL(mem_section); |
1448 | VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS); |
1449 | VMCOREINFO_STRUCT_SIZE(mem_section); |
1450 | VMCOREINFO_OFFSET(mem_section, section_mem_map); |
1451 | #endif |
1452 | VMCOREINFO_STRUCT_SIZE(page); |
1453 | VMCOREINFO_STRUCT_SIZE(pglist_data); |
1454 | VMCOREINFO_STRUCT_SIZE(zone); |
1455 | VMCOREINFO_STRUCT_SIZE(free_area); |
1456 | VMCOREINFO_STRUCT_SIZE(list_head); |
1457 | VMCOREINFO_SIZE(nodemask_t); |
1458 | VMCOREINFO_OFFSET(page, flags); |
1459 | VMCOREINFO_OFFSET(page, _count); |
1460 | VMCOREINFO_OFFSET(page, mapping); |
1461 | VMCOREINFO_OFFSET(page, lru); |
1462 | VMCOREINFO_OFFSET(pglist_data, node_zones); |
1463 | VMCOREINFO_OFFSET(pglist_data, nr_zones); |
1464 | #ifdef CONFIG_FLAT_NODE_MEM_MAP |
1465 | VMCOREINFO_OFFSET(pglist_data, node_mem_map); |
1466 | #endif |
1467 | VMCOREINFO_OFFSET(pglist_data, node_start_pfn); |
1468 | VMCOREINFO_OFFSET(pglist_data, node_spanned_pages); |
1469 | VMCOREINFO_OFFSET(pglist_data, node_id); |
1470 | VMCOREINFO_OFFSET(zone, free_area); |
1471 | VMCOREINFO_OFFSET(zone, vm_stat); |
1472 | VMCOREINFO_OFFSET(zone, spanned_pages); |
1473 | VMCOREINFO_OFFSET(free_area, free_list); |
1474 | VMCOREINFO_OFFSET(list_head, next); |
1475 | VMCOREINFO_OFFSET(list_head, prev); |
1476 | VMCOREINFO_OFFSET(vm_struct, addr); |
1477 | VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); |
1478 | log_buf_kexec_setup(); |
1479 | VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); |
1480 | VMCOREINFO_NUMBER(NR_FREE_PAGES); |
1481 | VMCOREINFO_NUMBER(PG_lru); |
1482 | VMCOREINFO_NUMBER(PG_private); |
1483 | VMCOREINFO_NUMBER(PG_swapcache); |
1484 | |
1485 | arch_crash_save_vmcoreinfo(); |
1486 | |
1487 | return 0; |
1488 | } |
1489 | |
1490 | module_init(crash_save_vmcoreinfo_init) |
1491 | |
1492 | /* |
1493 | * Move into place and start executing a preloaded standalone |
1494 | * executable. If nothing was preloaded return an error. |
1495 | */ |
1496 | int kernel_kexec(void) |
1497 | { |
1498 | int error = 0; |
1499 | |
1500 | if (!mutex_trylock(&kexec_mutex)) |
1501 | return -EBUSY; |
1502 | if (!kexec_image) { |
1503 | error = -EINVAL; |
1504 | goto Unlock; |
1505 | } |
1506 | |
1507 | #ifdef CONFIG_KEXEC_JUMP |
1508 | if (kexec_image->preserve_context) { |
1509 | mutex_lock(&pm_mutex); |
1510 | pm_prepare_console(); |
1511 | error = freeze_processes(); |
1512 | if (error) { |
1513 | error = -EBUSY; |
1514 | goto Restore_console; |
1515 | } |
1516 | suspend_console(); |
1517 | error = dpm_suspend_start(PMSG_FREEZE); |
1518 | if (error) |
1519 | goto Resume_console; |
1520 | /* At this point, dpm_suspend_start() has been called, |
1521 | * but *not* dpm_suspend_noirq(). We *must* call |
1522 | * dpm_suspend_noirq() now. Otherwise, drivers for |
1523 | * some devices (e.g. interrupt controllers) become |
1524 | * desynchronized with the actual state of the |
1525 | * hardware at resume time, and evil weirdness ensues. |
1526 | */ |
1527 | error = dpm_suspend_noirq(PMSG_FREEZE); |
1528 | if (error) |
1529 | goto Resume_devices; |
1530 | error = disable_nonboot_cpus(); |
1531 | if (error) |
1532 | goto Enable_cpus; |
1533 | local_irq_disable(); |
1534 | error = syscore_suspend(); |
1535 | if (error) |
1536 | goto Enable_irqs; |
1537 | } else |
1538 | #endif |
1539 | { |
1540 | kernel_restart_prepare(NULL); |
1541 | printk(KERN_EMERG "Starting new kernel\n"); |
1542 | machine_shutdown(); |
1543 | } |
1544 | |
1545 | machine_kexec(kexec_image); |
1546 | |
1547 | #ifdef CONFIG_KEXEC_JUMP |
1548 | if (kexec_image->preserve_context) { |
1549 | syscore_resume(); |
1550 | Enable_irqs: |
1551 | local_irq_enable(); |
1552 | Enable_cpus: |
1553 | enable_nonboot_cpus(); |
1554 | dpm_resume_noirq(PMSG_RESTORE); |
1555 | Resume_devices: |
1556 | dpm_resume_end(PMSG_RESTORE); |
1557 | Resume_console: |
1558 | resume_console(); |
1559 | thaw_processes(); |
1560 | Restore_console: |
1561 | pm_restore_console(); |
1562 | mutex_unlock(&pm_mutex); |
1563 | } |
1564 | #endif |
1565 | |
1566 | Unlock: |
1567 | mutex_unlock(&kexec_mutex); |
1568 | return error; |
1569 | } |
1570 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9