Commit | Line | Data |
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eb39c880 MS |
1 | /* |
2 | * Firmware Assisted dump: A robust mechanism to get reliable kernel crash | |
3 | * dump with assistance from firmware. This approach does not use kexec, | |
4 | * instead firmware assists in booting the kdump kernel while preserving | |
5 | * memory contents. The most of the code implementation has been adapted | |
6 | * from phyp assisted dump implementation written by Linas Vepstas and | |
7 | * Manish Ahuja | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License | |
20 | * along with this program; if not, write to the Free Software | |
21 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
22 | * | |
23 | * Copyright 2011 IBM Corporation | |
24 | * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> | |
25 | */ | |
26 | ||
27 | #undef DEBUG | |
28 | #define pr_fmt(fmt) "fadump: " fmt | |
29 | ||
30 | #include <linux/string.h> | |
31 | #include <linux/memblock.h> | |
3ccc00a7 MS |
32 | #include <linux/delay.h> |
33 | #include <linux/debugfs.h> | |
34 | #include <linux/seq_file.h> | |
2df173d9 | 35 | #include <linux/crash_dump.h> |
eb39c880 MS |
36 | |
37 | #include <asm/page.h> | |
38 | #include <asm/prom.h> | |
39 | #include <asm/rtas.h> | |
40 | #include <asm/fadump.h> | |
41 | ||
42 | static struct fw_dump fw_dump; | |
3ccc00a7 MS |
43 | static struct fadump_mem_struct fdm; |
44 | static const struct fadump_mem_struct *fdm_active; | |
45 | ||
46 | static DEFINE_MUTEX(fadump_mutex); | |
2df173d9 MS |
47 | struct fad_crash_memory_ranges crash_memory_ranges[INIT_CRASHMEM_RANGES]; |
48 | int crash_mem_ranges; | |
eb39c880 MS |
49 | |
50 | /* Scan the Firmware Assisted dump configuration details. */ | |
51 | int __init early_init_dt_scan_fw_dump(unsigned long node, | |
52 | const char *uname, int depth, void *data) | |
53 | { | |
54 | __be32 *sections; | |
55 | int i, num_sections; | |
56 | unsigned long size; | |
57 | const int *token; | |
58 | ||
59 | if (depth != 1 || strcmp(uname, "rtas") != 0) | |
60 | return 0; | |
61 | ||
62 | /* | |
63 | * Check if Firmware Assisted dump is supported. if yes, check | |
64 | * if dump has been initiated on last reboot. | |
65 | */ | |
66 | token = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump", NULL); | |
67 | if (!token) | |
68 | return 0; | |
69 | ||
70 | fw_dump.fadump_supported = 1; | |
71 | fw_dump.ibm_configure_kernel_dump = *token; | |
72 | ||
73 | /* | |
74 | * The 'ibm,kernel-dump' rtas node is present only if there is | |
75 | * dump data waiting for us. | |
76 | */ | |
3ccc00a7 MS |
77 | fdm_active = of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL); |
78 | if (fdm_active) | |
eb39c880 MS |
79 | fw_dump.dump_active = 1; |
80 | ||
81 | /* Get the sizes required to store dump data for the firmware provided | |
82 | * dump sections. | |
83 | * For each dump section type supported, a 32bit cell which defines | |
84 | * the ID of a supported section followed by two 32 bit cells which | |
85 | * gives teh size of the section in bytes. | |
86 | */ | |
87 | sections = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump-sizes", | |
88 | &size); | |
89 | ||
90 | if (!sections) | |
91 | return 0; | |
92 | ||
93 | num_sections = size / (3 * sizeof(u32)); | |
94 | ||
95 | for (i = 0; i < num_sections; i++, sections += 3) { | |
96 | u32 type = (u32)of_read_number(sections, 1); | |
97 | ||
98 | switch (type) { | |
99 | case FADUMP_CPU_STATE_DATA: | |
100 | fw_dump.cpu_state_data_size = | |
101 | of_read_ulong(§ions[1], 2); | |
102 | break; | |
103 | case FADUMP_HPTE_REGION: | |
104 | fw_dump.hpte_region_size = | |
105 | of_read_ulong(§ions[1], 2); | |
106 | break; | |
107 | } | |
108 | } | |
109 | return 1; | |
110 | } | |
111 | ||
3ccc00a7 MS |
112 | int is_fadump_active(void) |
113 | { | |
114 | return fw_dump.dump_active; | |
115 | } | |
116 | ||
117 | /* Print firmware assisted dump configurations for debugging purpose. */ | |
118 | static void fadump_show_config(void) | |
119 | { | |
120 | pr_debug("Support for firmware-assisted dump (fadump): %s\n", | |
121 | (fw_dump.fadump_supported ? "present" : "no support")); | |
122 | ||
123 | if (!fw_dump.fadump_supported) | |
124 | return; | |
125 | ||
126 | pr_debug("Fadump enabled : %s\n", | |
127 | (fw_dump.fadump_enabled ? "yes" : "no")); | |
128 | pr_debug("Dump Active : %s\n", | |
129 | (fw_dump.dump_active ? "yes" : "no")); | |
130 | pr_debug("Dump section sizes:\n"); | |
131 | pr_debug(" CPU state data size: %lx\n", fw_dump.cpu_state_data_size); | |
132 | pr_debug(" HPTE region size : %lx\n", fw_dump.hpte_region_size); | |
133 | pr_debug("Boot memory size : %lx\n", fw_dump.boot_memory_size); | |
134 | } | |
135 | ||
136 | static unsigned long init_fadump_mem_struct(struct fadump_mem_struct *fdm, | |
137 | unsigned long addr) | |
138 | { | |
139 | if (!fdm) | |
140 | return 0; | |
141 | ||
142 | memset(fdm, 0, sizeof(struct fadump_mem_struct)); | |
143 | addr = addr & PAGE_MASK; | |
144 | ||
145 | fdm->header.dump_format_version = 0x00000001; | |
146 | fdm->header.dump_num_sections = 3; | |
147 | fdm->header.dump_status_flag = 0; | |
148 | fdm->header.offset_first_dump_section = | |
149 | (u32)offsetof(struct fadump_mem_struct, cpu_state_data); | |
150 | ||
151 | /* | |
152 | * Fields for disk dump option. | |
153 | * We are not using disk dump option, hence set these fields to 0. | |
154 | */ | |
155 | fdm->header.dd_block_size = 0; | |
156 | fdm->header.dd_block_offset = 0; | |
157 | fdm->header.dd_num_blocks = 0; | |
158 | fdm->header.dd_offset_disk_path = 0; | |
159 | ||
160 | /* set 0 to disable an automatic dump-reboot. */ | |
161 | fdm->header.max_time_auto = 0; | |
162 | ||
163 | /* Kernel dump sections */ | |
164 | /* cpu state data section. */ | |
165 | fdm->cpu_state_data.request_flag = FADUMP_REQUEST_FLAG; | |
166 | fdm->cpu_state_data.source_data_type = FADUMP_CPU_STATE_DATA; | |
167 | fdm->cpu_state_data.source_address = 0; | |
168 | fdm->cpu_state_data.source_len = fw_dump.cpu_state_data_size; | |
169 | fdm->cpu_state_data.destination_address = addr; | |
170 | addr += fw_dump.cpu_state_data_size; | |
171 | ||
172 | /* hpte region section */ | |
173 | fdm->hpte_region.request_flag = FADUMP_REQUEST_FLAG; | |
174 | fdm->hpte_region.source_data_type = FADUMP_HPTE_REGION; | |
175 | fdm->hpte_region.source_address = 0; | |
176 | fdm->hpte_region.source_len = fw_dump.hpte_region_size; | |
177 | fdm->hpte_region.destination_address = addr; | |
178 | addr += fw_dump.hpte_region_size; | |
179 | ||
180 | /* RMA region section */ | |
181 | fdm->rmr_region.request_flag = FADUMP_REQUEST_FLAG; | |
182 | fdm->rmr_region.source_data_type = FADUMP_REAL_MODE_REGION; | |
183 | fdm->rmr_region.source_address = RMA_START; | |
184 | fdm->rmr_region.source_len = fw_dump.boot_memory_size; | |
185 | fdm->rmr_region.destination_address = addr; | |
186 | addr += fw_dump.boot_memory_size; | |
187 | ||
188 | return addr; | |
189 | } | |
190 | ||
eb39c880 MS |
191 | /** |
192 | * fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM | |
193 | * | |
194 | * Function to find the largest memory size we need to reserve during early | |
195 | * boot process. This will be the size of the memory that is required for a | |
196 | * kernel to boot successfully. | |
197 | * | |
198 | * This function has been taken from phyp-assisted dump feature implementation. | |
199 | * | |
200 | * returns larger of 256MB or 5% rounded down to multiples of 256MB. | |
201 | * | |
202 | * TODO: Come up with better approach to find out more accurate memory size | |
203 | * that is required for a kernel to boot successfully. | |
204 | * | |
205 | */ | |
206 | static inline unsigned long fadump_calculate_reserve_size(void) | |
207 | { | |
208 | unsigned long size; | |
209 | ||
210 | /* | |
211 | * Check if the size is specified through fadump_reserve_mem= cmdline | |
212 | * option. If yes, then use that. | |
213 | */ | |
214 | if (fw_dump.reserve_bootvar) | |
215 | return fw_dump.reserve_bootvar; | |
216 | ||
217 | /* divide by 20 to get 5% of value */ | |
218 | size = memblock_end_of_DRAM() / 20; | |
219 | ||
220 | /* round it down in multiples of 256 */ | |
221 | size = size & ~0x0FFFFFFFUL; | |
222 | ||
223 | /* Truncate to memory_limit. We don't want to over reserve the memory.*/ | |
224 | if (memory_limit && size > memory_limit) | |
225 | size = memory_limit; | |
226 | ||
227 | return (size > MIN_BOOT_MEM ? size : MIN_BOOT_MEM); | |
228 | } | |
229 | ||
230 | /* | |
231 | * Calculate the total memory size required to be reserved for | |
232 | * firmware-assisted dump registration. | |
233 | */ | |
234 | static unsigned long get_fadump_area_size(void) | |
235 | { | |
236 | unsigned long size = 0; | |
237 | ||
238 | size += fw_dump.cpu_state_data_size; | |
239 | size += fw_dump.hpte_region_size; | |
240 | size += fw_dump.boot_memory_size; | |
2df173d9 MS |
241 | size += sizeof(struct fadump_crash_info_header); |
242 | size += sizeof(struct elfhdr); /* ELF core header.*/ | |
243 | /* Program headers for crash memory regions. */ | |
244 | size += sizeof(struct elf_phdr) * (memblock_num_regions(memory) + 2); | |
eb39c880 MS |
245 | |
246 | size = PAGE_ALIGN(size); | |
247 | return size; | |
248 | } | |
249 | ||
250 | int __init fadump_reserve_mem(void) | |
251 | { | |
252 | unsigned long base, size, memory_boundary; | |
253 | ||
254 | if (!fw_dump.fadump_enabled) | |
255 | return 0; | |
256 | ||
257 | if (!fw_dump.fadump_supported) { | |
258 | printk(KERN_INFO "Firmware-assisted dump is not supported on" | |
259 | " this hardware\n"); | |
260 | fw_dump.fadump_enabled = 0; | |
261 | return 0; | |
262 | } | |
3ccc00a7 MS |
263 | /* |
264 | * Initialize boot memory size | |
265 | * If dump is active then we have already calculated the size during | |
266 | * first kernel. | |
267 | */ | |
268 | if (fdm_active) | |
269 | fw_dump.boot_memory_size = fdm_active->rmr_region.source_len; | |
270 | else | |
271 | fw_dump.boot_memory_size = fadump_calculate_reserve_size(); | |
eb39c880 MS |
272 | |
273 | /* | |
274 | * Calculate the memory boundary. | |
275 | * If memory_limit is less than actual memory boundary then reserve | |
276 | * the memory for fadump beyond the memory_limit and adjust the | |
277 | * memory_limit accordingly, so that the running kernel can run with | |
278 | * specified memory_limit. | |
279 | */ | |
280 | if (memory_limit && memory_limit < memblock_end_of_DRAM()) { | |
281 | size = get_fadump_area_size(); | |
282 | if ((memory_limit + size) < memblock_end_of_DRAM()) | |
283 | memory_limit += size; | |
284 | else | |
285 | memory_limit = memblock_end_of_DRAM(); | |
286 | printk(KERN_INFO "Adjusted memory_limit for firmware-assisted" | |
287 | " dump, now %#016llx\n", | |
288 | (unsigned long long)memory_limit); | |
289 | } | |
290 | if (memory_limit) | |
291 | memory_boundary = memory_limit; | |
292 | else | |
293 | memory_boundary = memblock_end_of_DRAM(); | |
294 | ||
295 | if (fw_dump.dump_active) { | |
296 | printk(KERN_INFO "Firmware-assisted dump is active.\n"); | |
297 | /* | |
298 | * If last boot has crashed then reserve all the memory | |
299 | * above boot_memory_size so that we don't touch it until | |
300 | * dump is written to disk by userspace tool. This memory | |
301 | * will be released for general use once the dump is saved. | |
302 | */ | |
303 | base = fw_dump.boot_memory_size; | |
304 | size = memory_boundary - base; | |
305 | memblock_reserve(base, size); | |
306 | printk(KERN_INFO "Reserved %ldMB of memory at %ldMB " | |
307 | "for saving crash dump\n", | |
308 | (unsigned long)(size >> 20), | |
309 | (unsigned long)(base >> 20)); | |
2df173d9 MS |
310 | |
311 | fw_dump.fadumphdr_addr = | |
312 | fdm_active->rmr_region.destination_address + | |
313 | fdm_active->rmr_region.source_len; | |
314 | pr_debug("fadumphdr_addr = %p\n", | |
315 | (void *) fw_dump.fadumphdr_addr); | |
eb39c880 MS |
316 | } else { |
317 | /* Reserve the memory at the top of memory. */ | |
318 | size = get_fadump_area_size(); | |
319 | base = memory_boundary - size; | |
320 | memblock_reserve(base, size); | |
321 | printk(KERN_INFO "Reserved %ldMB of memory at %ldMB " | |
322 | "for firmware-assisted dump\n", | |
323 | (unsigned long)(size >> 20), | |
324 | (unsigned long)(base >> 20)); | |
325 | } | |
326 | fw_dump.reserve_dump_area_start = base; | |
327 | fw_dump.reserve_dump_area_size = size; | |
328 | return 1; | |
329 | } | |
330 | ||
331 | /* Look for fadump= cmdline option. */ | |
332 | static int __init early_fadump_param(char *p) | |
333 | { | |
334 | if (!p) | |
335 | return 1; | |
336 | ||
337 | if (strncmp(p, "on", 2) == 0) | |
338 | fw_dump.fadump_enabled = 1; | |
339 | else if (strncmp(p, "off", 3) == 0) | |
340 | fw_dump.fadump_enabled = 0; | |
341 | ||
342 | return 0; | |
343 | } | |
344 | early_param("fadump", early_fadump_param); | |
345 | ||
346 | /* Look for fadump_reserve_mem= cmdline option */ | |
347 | static int __init early_fadump_reserve_mem(char *p) | |
348 | { | |
349 | if (p) | |
350 | fw_dump.reserve_bootvar = memparse(p, &p); | |
351 | return 0; | |
352 | } | |
353 | early_param("fadump_reserve_mem", early_fadump_reserve_mem); | |
3ccc00a7 MS |
354 | |
355 | static void register_fw_dump(struct fadump_mem_struct *fdm) | |
356 | { | |
357 | int rc; | |
358 | unsigned int wait_time; | |
359 | ||
360 | pr_debug("Registering for firmware-assisted kernel dump...\n"); | |
361 | ||
362 | /* TODO: Add upper time limit for the delay */ | |
363 | do { | |
364 | rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, | |
365 | FADUMP_REGISTER, fdm, | |
366 | sizeof(struct fadump_mem_struct)); | |
367 | ||
368 | wait_time = rtas_busy_delay_time(rc); | |
369 | if (wait_time) | |
370 | mdelay(wait_time); | |
371 | ||
372 | } while (wait_time); | |
373 | ||
374 | switch (rc) { | |
375 | case -1: | |
376 | printk(KERN_ERR "Failed to register firmware-assisted kernel" | |
377 | " dump. Hardware Error(%d).\n", rc); | |
378 | break; | |
379 | case -3: | |
380 | printk(KERN_ERR "Failed to register firmware-assisted kernel" | |
381 | " dump. Parameter Error(%d).\n", rc); | |
382 | break; | |
383 | case -9: | |
384 | printk(KERN_ERR "firmware-assisted kernel dump is already " | |
385 | " registered."); | |
386 | fw_dump.dump_registered = 1; | |
387 | break; | |
388 | case 0: | |
389 | printk(KERN_INFO "firmware-assisted kernel dump registration" | |
390 | " is successful\n"); | |
391 | fw_dump.dump_registered = 1; | |
392 | break; | |
393 | } | |
394 | } | |
395 | ||
2df173d9 MS |
396 | /* |
397 | * Validate and process the dump data stored by firmware before exporting | |
398 | * it through '/proc/vmcore'. | |
399 | */ | |
400 | static int __init process_fadump(const struct fadump_mem_struct *fdm_active) | |
401 | { | |
402 | struct fadump_crash_info_header *fdh; | |
403 | ||
404 | if (!fdm_active || !fw_dump.fadumphdr_addr) | |
405 | return -EINVAL; | |
406 | ||
407 | /* Check if the dump data is valid. */ | |
408 | if ((fdm_active->header.dump_status_flag == FADUMP_ERROR_FLAG) || | |
409 | (fdm_active->rmr_region.error_flags != 0)) { | |
410 | printk(KERN_ERR "Dump taken by platform is not valid\n"); | |
411 | return -EINVAL; | |
412 | } | |
413 | if (fdm_active->rmr_region.bytes_dumped != | |
414 | fdm_active->rmr_region.source_len) { | |
415 | printk(KERN_ERR "Dump taken by platform is incomplete\n"); | |
416 | return -EINVAL; | |
417 | } | |
418 | ||
419 | /* Validate the fadump crash info header */ | |
420 | fdh = __va(fw_dump.fadumphdr_addr); | |
421 | if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { | |
422 | printk(KERN_ERR "Crash info header is not valid.\n"); | |
423 | return -EINVAL; | |
424 | } | |
425 | ||
426 | /* | |
427 | * We are done validating dump info and elfcore header is now ready | |
428 | * to be exported. set elfcorehdr_addr so that vmcore module will | |
429 | * export the elfcore header through '/proc/vmcore'. | |
430 | */ | |
431 | elfcorehdr_addr = fdh->elfcorehdr_addr; | |
432 | ||
433 | return 0; | |
434 | } | |
435 | ||
436 | static inline void fadump_add_crash_memory(unsigned long long base, | |
437 | unsigned long long end) | |
438 | { | |
439 | if (base == end) | |
440 | return; | |
441 | ||
442 | pr_debug("crash_memory_range[%d] [%#016llx-%#016llx], %#llx bytes\n", | |
443 | crash_mem_ranges, base, end - 1, (end - base)); | |
444 | crash_memory_ranges[crash_mem_ranges].base = base; | |
445 | crash_memory_ranges[crash_mem_ranges].size = end - base; | |
446 | crash_mem_ranges++; | |
447 | } | |
448 | ||
449 | static void fadump_exclude_reserved_area(unsigned long long start, | |
450 | unsigned long long end) | |
451 | { | |
452 | unsigned long long ra_start, ra_end; | |
453 | ||
454 | ra_start = fw_dump.reserve_dump_area_start; | |
455 | ra_end = ra_start + fw_dump.reserve_dump_area_size; | |
456 | ||
457 | if ((ra_start < end) && (ra_end > start)) { | |
458 | if ((start < ra_start) && (end > ra_end)) { | |
459 | fadump_add_crash_memory(start, ra_start); | |
460 | fadump_add_crash_memory(ra_end, end); | |
461 | } else if (start < ra_start) { | |
462 | fadump_add_crash_memory(start, ra_start); | |
463 | } else if (ra_end < end) { | |
464 | fadump_add_crash_memory(ra_end, end); | |
465 | } | |
466 | } else | |
467 | fadump_add_crash_memory(start, end); | |
468 | } | |
469 | ||
470 | static int fadump_init_elfcore_header(char *bufp) | |
471 | { | |
472 | struct elfhdr *elf; | |
473 | ||
474 | elf = (struct elfhdr *) bufp; | |
475 | bufp += sizeof(struct elfhdr); | |
476 | memcpy(elf->e_ident, ELFMAG, SELFMAG); | |
477 | elf->e_ident[EI_CLASS] = ELF_CLASS; | |
478 | elf->e_ident[EI_DATA] = ELF_DATA; | |
479 | elf->e_ident[EI_VERSION] = EV_CURRENT; | |
480 | elf->e_ident[EI_OSABI] = ELF_OSABI; | |
481 | memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); | |
482 | elf->e_type = ET_CORE; | |
483 | elf->e_machine = ELF_ARCH; | |
484 | elf->e_version = EV_CURRENT; | |
485 | elf->e_entry = 0; | |
486 | elf->e_phoff = sizeof(struct elfhdr); | |
487 | elf->e_shoff = 0; | |
488 | elf->e_flags = ELF_CORE_EFLAGS; | |
489 | elf->e_ehsize = sizeof(struct elfhdr); | |
490 | elf->e_phentsize = sizeof(struct elf_phdr); | |
491 | elf->e_phnum = 0; | |
492 | elf->e_shentsize = 0; | |
493 | elf->e_shnum = 0; | |
494 | elf->e_shstrndx = 0; | |
495 | ||
496 | return 0; | |
497 | } | |
498 | ||
499 | /* | |
500 | * Traverse through memblock structure and setup crash memory ranges. These | |
501 | * ranges will be used create PT_LOAD program headers in elfcore header. | |
502 | */ | |
503 | static void fadump_setup_crash_memory_ranges(void) | |
504 | { | |
505 | struct memblock_region *reg; | |
506 | unsigned long long start, end; | |
507 | ||
508 | pr_debug("Setup crash memory ranges.\n"); | |
509 | crash_mem_ranges = 0; | |
510 | /* | |
511 | * add the first memory chunk (RMA_START through boot_memory_size) as | |
512 | * a separate memory chunk. The reason is, at the time crash firmware | |
513 | * will move the content of this memory chunk to different location | |
514 | * specified during fadump registration. We need to create a separate | |
515 | * program header for this chunk with the correct offset. | |
516 | */ | |
517 | fadump_add_crash_memory(RMA_START, fw_dump.boot_memory_size); | |
518 | ||
519 | for_each_memblock(memory, reg) { | |
520 | start = (unsigned long long)reg->base; | |
521 | end = start + (unsigned long long)reg->size; | |
522 | if (start == RMA_START && end >= fw_dump.boot_memory_size) | |
523 | start = fw_dump.boot_memory_size; | |
524 | ||
525 | /* add this range excluding the reserved dump area. */ | |
526 | fadump_exclude_reserved_area(start, end); | |
527 | } | |
528 | } | |
529 | ||
530 | static int fadump_create_elfcore_headers(char *bufp) | |
531 | { | |
532 | struct elfhdr *elf; | |
533 | struct elf_phdr *phdr; | |
534 | int i; | |
535 | ||
536 | fadump_init_elfcore_header(bufp); | |
537 | elf = (struct elfhdr *)bufp; | |
538 | bufp += sizeof(struct elfhdr); | |
539 | ||
540 | /* setup PT_LOAD sections. */ | |
541 | ||
542 | for (i = 0; i < crash_mem_ranges; i++) { | |
543 | unsigned long long mbase, msize; | |
544 | mbase = crash_memory_ranges[i].base; | |
545 | msize = crash_memory_ranges[i].size; | |
546 | ||
547 | if (!msize) | |
548 | continue; | |
549 | ||
550 | phdr = (struct elf_phdr *)bufp; | |
551 | bufp += sizeof(struct elf_phdr); | |
552 | phdr->p_type = PT_LOAD; | |
553 | phdr->p_flags = PF_R|PF_W|PF_X; | |
554 | phdr->p_offset = mbase; | |
555 | ||
556 | if (mbase == RMA_START) { | |
557 | /* | |
558 | * The entire RMA region will be moved by firmware | |
559 | * to the specified destination_address. Hence set | |
560 | * the correct offset. | |
561 | */ | |
562 | phdr->p_offset = fdm.rmr_region.destination_address; | |
563 | } | |
564 | ||
565 | phdr->p_paddr = mbase; | |
566 | phdr->p_vaddr = (unsigned long)__va(mbase); | |
567 | phdr->p_filesz = msize; | |
568 | phdr->p_memsz = msize; | |
569 | phdr->p_align = 0; | |
570 | ||
571 | /* Increment number of program headers. */ | |
572 | (elf->e_phnum)++; | |
573 | } | |
574 | return 0; | |
575 | } | |
576 | ||
577 | static unsigned long init_fadump_header(unsigned long addr) | |
578 | { | |
579 | struct fadump_crash_info_header *fdh; | |
580 | ||
581 | if (!addr) | |
582 | return 0; | |
583 | ||
584 | fw_dump.fadumphdr_addr = addr; | |
585 | fdh = __va(addr); | |
586 | addr += sizeof(struct fadump_crash_info_header); | |
587 | ||
588 | memset(fdh, 0, sizeof(struct fadump_crash_info_header)); | |
589 | fdh->magic_number = FADUMP_CRASH_INFO_MAGIC; | |
590 | fdh->elfcorehdr_addr = addr; | |
591 | ||
592 | return addr; | |
593 | } | |
594 | ||
3ccc00a7 MS |
595 | static void register_fadump(void) |
596 | { | |
2df173d9 MS |
597 | unsigned long addr; |
598 | void *vaddr; | |
599 | ||
3ccc00a7 MS |
600 | /* |
601 | * If no memory is reserved then we can not register for firmware- | |
602 | * assisted dump. | |
603 | */ | |
604 | if (!fw_dump.reserve_dump_area_size) | |
605 | return; | |
606 | ||
2df173d9 MS |
607 | fadump_setup_crash_memory_ranges(); |
608 | ||
609 | addr = fdm.rmr_region.destination_address + fdm.rmr_region.source_len; | |
610 | /* Initialize fadump crash info header. */ | |
611 | addr = init_fadump_header(addr); | |
612 | vaddr = __va(addr); | |
613 | ||
614 | pr_debug("Creating ELF core headers at %#016lx\n", addr); | |
615 | fadump_create_elfcore_headers(vaddr); | |
616 | ||
3ccc00a7 MS |
617 | /* register the future kernel dump with firmware. */ |
618 | register_fw_dump(&fdm); | |
619 | } | |
620 | ||
621 | static int fadump_unregister_dump(struct fadump_mem_struct *fdm) | |
622 | { | |
623 | int rc = 0; | |
624 | unsigned int wait_time; | |
625 | ||
626 | pr_debug("Un-register firmware-assisted dump\n"); | |
627 | ||
628 | /* TODO: Add upper time limit for the delay */ | |
629 | do { | |
630 | rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, | |
631 | FADUMP_UNREGISTER, fdm, | |
632 | sizeof(struct fadump_mem_struct)); | |
633 | ||
634 | wait_time = rtas_busy_delay_time(rc); | |
635 | if (wait_time) | |
636 | mdelay(wait_time); | |
637 | } while (wait_time); | |
638 | ||
639 | if (rc) { | |
640 | printk(KERN_ERR "Failed to un-register firmware-assisted dump." | |
641 | " unexpected error(%d).\n", rc); | |
642 | return rc; | |
643 | } | |
644 | fw_dump.dump_registered = 0; | |
645 | return 0; | |
646 | } | |
647 | ||
648 | static ssize_t fadump_enabled_show(struct kobject *kobj, | |
649 | struct kobj_attribute *attr, | |
650 | char *buf) | |
651 | { | |
652 | return sprintf(buf, "%d\n", fw_dump.fadump_enabled); | |
653 | } | |
654 | ||
655 | static ssize_t fadump_register_show(struct kobject *kobj, | |
656 | struct kobj_attribute *attr, | |
657 | char *buf) | |
658 | { | |
659 | return sprintf(buf, "%d\n", fw_dump.dump_registered); | |
660 | } | |
661 | ||
662 | static ssize_t fadump_register_store(struct kobject *kobj, | |
663 | struct kobj_attribute *attr, | |
664 | const char *buf, size_t count) | |
665 | { | |
666 | int ret = 0; | |
667 | ||
668 | if (!fw_dump.fadump_enabled || fdm_active) | |
669 | return -EPERM; | |
670 | ||
671 | mutex_lock(&fadump_mutex); | |
672 | ||
673 | switch (buf[0]) { | |
674 | case '0': | |
675 | if (fw_dump.dump_registered == 0) { | |
676 | ret = -EINVAL; | |
677 | goto unlock_out; | |
678 | } | |
679 | /* Un-register Firmware-assisted dump */ | |
680 | fadump_unregister_dump(&fdm); | |
681 | break; | |
682 | case '1': | |
683 | if (fw_dump.dump_registered == 1) { | |
684 | ret = -EINVAL; | |
685 | goto unlock_out; | |
686 | } | |
687 | /* Register Firmware-assisted dump */ | |
688 | register_fadump(); | |
689 | break; | |
690 | default: | |
691 | ret = -EINVAL; | |
692 | break; | |
693 | } | |
694 | ||
695 | unlock_out: | |
696 | mutex_unlock(&fadump_mutex); | |
697 | return ret < 0 ? ret : count; | |
698 | } | |
699 | ||
700 | static int fadump_region_show(struct seq_file *m, void *private) | |
701 | { | |
702 | const struct fadump_mem_struct *fdm_ptr; | |
703 | ||
704 | if (!fw_dump.fadump_enabled) | |
705 | return 0; | |
706 | ||
707 | if (fdm_active) | |
708 | fdm_ptr = fdm_active; | |
709 | else | |
710 | fdm_ptr = &fdm; | |
711 | ||
712 | seq_printf(m, | |
713 | "CPU : [%#016llx-%#016llx] %#llx bytes, " | |
714 | "Dumped: %#llx\n", | |
715 | fdm_ptr->cpu_state_data.destination_address, | |
716 | fdm_ptr->cpu_state_data.destination_address + | |
717 | fdm_ptr->cpu_state_data.source_len - 1, | |
718 | fdm_ptr->cpu_state_data.source_len, | |
719 | fdm_ptr->cpu_state_data.bytes_dumped); | |
720 | seq_printf(m, | |
721 | "HPTE: [%#016llx-%#016llx] %#llx bytes, " | |
722 | "Dumped: %#llx\n", | |
723 | fdm_ptr->hpte_region.destination_address, | |
724 | fdm_ptr->hpte_region.destination_address + | |
725 | fdm_ptr->hpte_region.source_len - 1, | |
726 | fdm_ptr->hpte_region.source_len, | |
727 | fdm_ptr->hpte_region.bytes_dumped); | |
728 | seq_printf(m, | |
729 | "DUMP: [%#016llx-%#016llx] %#llx bytes, " | |
730 | "Dumped: %#llx\n", | |
731 | fdm_ptr->rmr_region.destination_address, | |
732 | fdm_ptr->rmr_region.destination_address + | |
733 | fdm_ptr->rmr_region.source_len - 1, | |
734 | fdm_ptr->rmr_region.source_len, | |
735 | fdm_ptr->rmr_region.bytes_dumped); | |
736 | ||
737 | if (!fdm_active || | |
738 | (fw_dump.reserve_dump_area_start == | |
739 | fdm_ptr->cpu_state_data.destination_address)) | |
740 | return 0; | |
741 | ||
742 | /* Dump is active. Show reserved memory region. */ | |
743 | seq_printf(m, | |
744 | " : [%#016llx-%#016llx] %#llx bytes, " | |
745 | "Dumped: %#llx\n", | |
746 | (unsigned long long)fw_dump.reserve_dump_area_start, | |
747 | fdm_ptr->cpu_state_data.destination_address - 1, | |
748 | fdm_ptr->cpu_state_data.destination_address - | |
749 | fw_dump.reserve_dump_area_start, | |
750 | fdm_ptr->cpu_state_data.destination_address - | |
751 | fw_dump.reserve_dump_area_start); | |
752 | return 0; | |
753 | } | |
754 | ||
755 | static struct kobj_attribute fadump_attr = __ATTR(fadump_enabled, | |
756 | 0444, fadump_enabled_show, | |
757 | NULL); | |
758 | static struct kobj_attribute fadump_register_attr = __ATTR(fadump_registered, | |
759 | 0644, fadump_register_show, | |
760 | fadump_register_store); | |
761 | ||
762 | static int fadump_region_open(struct inode *inode, struct file *file) | |
763 | { | |
764 | return single_open(file, fadump_region_show, inode->i_private); | |
765 | } | |
766 | ||
767 | static const struct file_operations fadump_region_fops = { | |
768 | .open = fadump_region_open, | |
769 | .read = seq_read, | |
770 | .llseek = seq_lseek, | |
771 | .release = single_release, | |
772 | }; | |
773 | ||
774 | static void fadump_init_files(void) | |
775 | { | |
776 | struct dentry *debugfs_file; | |
777 | int rc = 0; | |
778 | ||
779 | rc = sysfs_create_file(kernel_kobj, &fadump_attr.attr); | |
780 | if (rc) | |
781 | printk(KERN_ERR "fadump: unable to create sysfs file" | |
782 | " fadump_enabled (%d)\n", rc); | |
783 | ||
784 | rc = sysfs_create_file(kernel_kobj, &fadump_register_attr.attr); | |
785 | if (rc) | |
786 | printk(KERN_ERR "fadump: unable to create sysfs file" | |
787 | " fadump_registered (%d)\n", rc); | |
788 | ||
789 | debugfs_file = debugfs_create_file("fadump_region", 0444, | |
790 | powerpc_debugfs_root, NULL, | |
791 | &fadump_region_fops); | |
792 | if (!debugfs_file) | |
793 | printk(KERN_ERR "fadump: unable to create debugfs file" | |
794 | " fadump_region\n"); | |
795 | return; | |
796 | } | |
797 | ||
798 | /* | |
799 | * Prepare for firmware-assisted dump. | |
800 | */ | |
801 | int __init setup_fadump(void) | |
802 | { | |
803 | if (!fw_dump.fadump_enabled) | |
804 | return 0; | |
805 | ||
806 | if (!fw_dump.fadump_supported) { | |
807 | printk(KERN_ERR "Firmware-assisted dump is not supported on" | |
808 | " this hardware\n"); | |
809 | return 0; | |
810 | } | |
811 | ||
812 | fadump_show_config(); | |
2df173d9 MS |
813 | /* |
814 | * If dump data is available then see if it is valid and prepare for | |
815 | * saving it to the disk. | |
816 | */ | |
817 | if (fw_dump.dump_active) | |
818 | process_fadump(fdm_active); | |
3ccc00a7 | 819 | /* Initialize the kernel dump memory structure for FAD registration. */ |
2df173d9 | 820 | else if (fw_dump.reserve_dump_area_size) |
3ccc00a7 MS |
821 | init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start); |
822 | fadump_init_files(); | |
823 | ||
824 | return 1; | |
825 | } | |
826 | subsys_initcall(setup_fadump); |