1 /*
2 * RAM Oops/Panic logger
3 *
4 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
5 * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19 * 02110-1301 USA
20 *
21 */
22
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25 #include <linux/kernel.h>
26 #include <linux/err.h>
27 #include <linux/module.h>
28 #include <linux/version.h>
29 #include <linux/pstore.h>
30 #include <linux/io.h>
31 #include <linux/ioport.h>
32 #include <linux/platform_device.h>
33 #include <linux/slab.h>
34 #include <linux/compiler.h>
35 #include <linux/pstore_ram.h>
36 #include <linux/of.h>
37 #include <linux/of_address.h>
38
39 #define RAMOOPS_KERNMSG_HDR "===="
40 #define MIN_MEM_SIZE 4096UL
41
42 static ulong record_size = MIN_MEM_SIZE;
43 module_param(record_size, ulong, 0400);
44 MODULE_PARM_DESC(record_size,
45 "size of each dump done on oops/panic");
46
47 static ulong ramoops_console_size = MIN_MEM_SIZE;
48 module_param_named(console_size, ramoops_console_size, ulong, 0400);
49 MODULE_PARM_DESC(console_size, "size of kernel console log");
50
51 static ulong ramoops_ftrace_size = MIN_MEM_SIZE;
52 module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400);
53 MODULE_PARM_DESC(ftrace_size, "size of ftrace log");
54
55 static ulong ramoops_pmsg_size = MIN_MEM_SIZE;
56 module_param_named(pmsg_size, ramoops_pmsg_size, ulong, 0400);
57 MODULE_PARM_DESC(pmsg_size, "size of user space message log");
58
59 static unsigned long long mem_address;
60 module_param_hw(mem_address, ullong, other, 0400);
61 MODULE_PARM_DESC(mem_address,
62 "start of reserved RAM used to store oops/panic logs");
63
64 static ulong mem_size;
65 module_param(mem_size, ulong, 0400);
66 MODULE_PARM_DESC(mem_size,
67 "size of reserved RAM used to store oops/panic logs");
68
69 static unsigned int mem_type;
70 module_param(mem_type, uint, 0600);
71 MODULE_PARM_DESC(mem_type,
72 "set to 1 to try to use unbuffered memory (default 0)");
73
74 static int dump_oops = 1;
75 module_param(dump_oops, int, 0600);
76 MODULE_PARM_DESC(dump_oops,
77 "set to 1 to dump oopses, 0 to only dump panics (default 1)");
78
79 static int ramoops_ecc;
80 module_param_named(ecc, ramoops_ecc, int, 0600);
81 MODULE_PARM_DESC(ramoops_ecc,
82 "if non-zero, the option enables ECC support and specifies "
83 "ECC buffer size in bytes (1 is a special value, means 16 "
84 "bytes ECC)");
85
86 struct ramoops_context {
87 struct persistent_ram_zone **dprzs; /* Oops dump zones */
88 struct persistent_ram_zone *cprz; /* Console zone */
89 struct persistent_ram_zone **fprzs; /* Ftrace zones */
90 struct persistent_ram_zone *mprz; /* PMSG zone */
91 phys_addr_t phys_addr;
92 unsigned long size;
93 unsigned int memtype;
94 size_t record_size;
95 size_t console_size;
96 size_t ftrace_size;
97 size_t pmsg_size;
98 int dump_oops;
99 u32 flags;
100 struct persistent_ram_ecc_info ecc_info;
101 unsigned int max_dump_cnt;
102 unsigned int dump_write_cnt;
103 /* _read_cnt need clear on ramoops_pstore_open */
104 unsigned int dump_read_cnt;
105 unsigned int console_read_cnt;
106 unsigned int max_ftrace_cnt;
107 unsigned int ftrace_read_cnt;
108 unsigned int pmsg_read_cnt;
109 struct pstore_info pstore;
110 };
111
112 static struct platform_device *dummy;
113 static struct ramoops_platform_data *dummy_data;
114
ramoops_pstore_open(struct pstore_info * psi)115 static int ramoops_pstore_open(struct pstore_info *psi)
116 {
117 struct ramoops_context *cxt = psi->data;
118
119 cxt->dump_read_cnt = 0;
120 cxt->console_read_cnt = 0;
121 cxt->ftrace_read_cnt = 0;
122 cxt->pmsg_read_cnt = 0;
123 return 0;
124 }
125
126 static struct persistent_ram_zone *
ramoops_get_next_prz(struct persistent_ram_zone * przs[],uint * c,uint max,u64 * id,enum pstore_type_id * typep,enum pstore_type_id type,bool update)127 ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
128 u64 *id,
129 enum pstore_type_id *typep, enum pstore_type_id type,
130 bool update)
131 {
132 struct persistent_ram_zone *prz;
133 int i = (*c)++;
134
135 /* Give up if we never existed or have hit the end. */
136 if (!przs || i >= max)
137 return NULL;
138
139 prz = przs[i];
140 if (!prz)
141 return NULL;
142
143 /* Update old/shadowed buffer. */
144 if (update)
145 persistent_ram_save_old(prz);
146
147 if (!persistent_ram_old_size(prz))
148 return NULL;
149
150 *typep = type;
151 *id = i;
152
153 return prz;
154 }
155
ramoops_read_kmsg_hdr(char * buffer,struct timespec * time,bool * compressed)156 static int ramoops_read_kmsg_hdr(char *buffer, struct timespec *time,
157 bool *compressed)
158 {
159 char data_type;
160 int header_length = 0;
161
162 if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n%n", &time->tv_sec,
163 &time->tv_nsec, &data_type, &header_length) == 3) {
164 if (data_type == 'C')
165 *compressed = true;
166 else
167 *compressed = false;
168 } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n%n",
169 &time->tv_sec, &time->tv_nsec, &header_length) == 2) {
170 *compressed = false;
171 } else {
172 time->tv_sec = 0;
173 time->tv_nsec = 0;
174 *compressed = false;
175 }
176 return header_length;
177 }
178
prz_ok(struct persistent_ram_zone * prz)179 static bool prz_ok(struct persistent_ram_zone *prz)
180 {
181 return !!prz && !!(persistent_ram_old_size(prz) +
182 persistent_ram_ecc_string(prz, NULL, 0));
183 }
184
ftrace_log_combine(struct persistent_ram_zone * dest,struct persistent_ram_zone * src)185 static ssize_t ftrace_log_combine(struct persistent_ram_zone *dest,
186 struct persistent_ram_zone *src)
187 {
188 size_t dest_size, src_size, total, dest_off, src_off;
189 size_t dest_idx = 0, src_idx = 0, merged_idx = 0;
190 void *merged_buf;
191 struct pstore_ftrace_record *drec, *srec, *mrec;
192 size_t record_size = sizeof(struct pstore_ftrace_record);
193
194 dest_off = dest->old_log_size % record_size;
195 dest_size = dest->old_log_size - dest_off;
196
197 src_off = src->old_log_size % record_size;
198 src_size = src->old_log_size - src_off;
199
200 total = dest_size + src_size;
201 merged_buf = kmalloc(total, GFP_KERNEL);
202 if (!merged_buf)
203 return -ENOMEM;
204
205 drec = (struct pstore_ftrace_record *)(dest->old_log + dest_off);
206 srec = (struct pstore_ftrace_record *)(src->old_log + src_off);
207 mrec = (struct pstore_ftrace_record *)(merged_buf);
208
209 while (dest_size > 0 && src_size > 0) {
210 if (pstore_ftrace_read_timestamp(&drec[dest_idx]) <
211 pstore_ftrace_read_timestamp(&srec[src_idx])) {
212 mrec[merged_idx++] = drec[dest_idx++];
213 dest_size -= record_size;
214 } else {
215 mrec[merged_idx++] = srec[src_idx++];
216 src_size -= record_size;
217 }
218 }
219
220 while (dest_size > 0) {
221 mrec[merged_idx++] = drec[dest_idx++];
222 dest_size -= record_size;
223 }
224
225 while (src_size > 0) {
226 mrec[merged_idx++] = srec[src_idx++];
227 src_size -= record_size;
228 }
229
230 kfree(dest->old_log);
231 dest->old_log = merged_buf;
232 dest->old_log_size = total;
233
234 return 0;
235 }
236
ramoops_pstore_read(struct pstore_record * record)237 static ssize_t ramoops_pstore_read(struct pstore_record *record)
238 {
239 ssize_t size = 0;
240 struct ramoops_context *cxt = record->psi->data;
241 struct persistent_ram_zone *prz = NULL;
242 int header_length = 0;
243 bool free_prz = false;
244
245 /*
246 * Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but
247 * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have
248 * valid time stamps, so it is initialized to zero.
249 */
250 record->time.tv_sec = 0;
251 record->time.tv_nsec = 0;
252 record->compressed = false;
253
254 /* Find the next valid persistent_ram_zone for DMESG */
255 while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) {
256 prz = ramoops_get_next_prz(cxt->dprzs, &cxt->dump_read_cnt,
257 cxt->max_dump_cnt, &record->id,
258 &record->type,
259 PSTORE_TYPE_DMESG, 1);
260 if (!prz_ok(prz))
261 continue;
262 header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz),
263 &record->time,
264 &record->compressed);
265 /* Clear and skip this DMESG record if it has no valid header */
266 if (!header_length) {
267 persistent_ram_free_old(prz);
268 persistent_ram_zap(prz);
269 prz = NULL;
270 }
271 }
272
273 if (!prz_ok(prz))
274 prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
275 1, &record->id, &record->type,
276 PSTORE_TYPE_CONSOLE, 0);
277
278 if (!prz_ok(prz))
279 prz = ramoops_get_next_prz(&cxt->mprz, &cxt->pmsg_read_cnt,
280 1, &record->id, &record->type,
281 PSTORE_TYPE_PMSG, 0);
282
283 /* ftrace is last since it may want to dynamically allocate memory. */
284 if (!prz_ok(prz)) {
285 if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)) {
286 prz = ramoops_get_next_prz(cxt->fprzs,
287 &cxt->ftrace_read_cnt, 1, &record->id,
288 &record->type, PSTORE_TYPE_FTRACE, 0);
289 } else {
290 /*
291 * Build a new dummy record which combines all the
292 * per-cpu records including metadata and ecc info.
293 */
294 struct persistent_ram_zone *tmp_prz, *prz_next;
295
296 tmp_prz = kzalloc(sizeof(struct persistent_ram_zone),
297 GFP_KERNEL);
298 if (!tmp_prz)
299 return -ENOMEM;
300 prz = tmp_prz;
301 free_prz = true;
302
303 while (cxt->ftrace_read_cnt < cxt->max_ftrace_cnt) {
304 prz_next = ramoops_get_next_prz(cxt->fprzs,
305 &cxt->ftrace_read_cnt,
306 cxt->max_ftrace_cnt,
307 &record->id,
308 &record->type,
309 PSTORE_TYPE_FTRACE, 0);
310
311 if (!prz_ok(prz_next))
312 continue;
313
314 tmp_prz->ecc_info = prz_next->ecc_info;
315 tmp_prz->corrected_bytes +=
316 prz_next->corrected_bytes;
317 tmp_prz->bad_blocks += prz_next->bad_blocks;
318 size = ftrace_log_combine(tmp_prz, prz_next);
319 if (size)
320 goto out;
321 }
322 record->id = 0;
323 }
324 }
325
326 if (!prz_ok(prz)) {
327 size = 0;
328 goto out;
329 }
330
331 size = persistent_ram_old_size(prz) - header_length;
332
333 /* ECC correction notice */
334 record->ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
335
336 record->buf = kmalloc(size + record->ecc_notice_size + 1, GFP_KERNEL);
337 if (record->buf == NULL) {
338 size = -ENOMEM;
339 goto out;
340 }
341
342 memcpy(record->buf, (char *)persistent_ram_old(prz) + header_length,
343 size);
344
345 persistent_ram_ecc_string(prz, record->buf + size,
346 record->ecc_notice_size + 1);
347
348 out:
349 if (free_prz) {
350 kfree(prz->old_log);
351 kfree(prz);
352 }
353
354 return size;
355 }
356
ramoops_write_kmsg_hdr(struct persistent_ram_zone * prz,struct pstore_record * record)357 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
358 struct pstore_record *record)
359 {
360 char *hdr;
361 size_t len;
362
363 hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
364 record->time.tv_sec,
365 record->time.tv_nsec / 1000,
366 record->compressed ? 'C' : 'D');
367 WARN_ON_ONCE(!hdr);
368 len = hdr ? strlen(hdr) : 0;
369 persistent_ram_write(prz, hdr, len);
370 kfree(hdr);
371
372 return len;
373 }
374
ramoops_pstore_write(struct pstore_record * record)375 static int notrace ramoops_pstore_write(struct pstore_record *record)
376 {
377 struct ramoops_context *cxt = record->psi->data;
378 struct persistent_ram_zone *prz;
379 size_t size, hlen;
380
381 if (record->type == PSTORE_TYPE_CONSOLE) {
382 if (!cxt->cprz)
383 return -ENOMEM;
384 persistent_ram_write(cxt->cprz, record->buf, record->size);
385 return 0;
386 } else if (record->type == PSTORE_TYPE_FTRACE) {
387 int zonenum;
388
389 if (!cxt->fprzs)
390 return -ENOMEM;
391 /*
392 * Choose zone by if we're using per-cpu buffers.
393 */
394 if (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)
395 zonenum = smp_processor_id();
396 else
397 zonenum = 0;
398
399 persistent_ram_write(cxt->fprzs[zonenum], record->buf,
400 record->size);
401 return 0;
402 } else if (record->type == PSTORE_TYPE_PMSG) {
403 pr_warn_ratelimited("PMSG shouldn't call %s\n", __func__);
404 return -EINVAL;
405 }
406
407 if (record->type != PSTORE_TYPE_DMESG)
408 return -EINVAL;
409
410 /*
411 * Out of the various dmesg dump types, ramoops is currently designed
412 * to only store crash logs, rather than storing general kernel logs.
413 */
414 if (record->reason != KMSG_DUMP_OOPS &&
415 record->reason != KMSG_DUMP_PANIC)
416 return -EINVAL;
417
418 /* Skip Oopes when configured to do so. */
419 if (record->reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
420 return -EINVAL;
421
422 /*
423 * Explicitly only take the first part of any new crash.
424 * If our buffer is larger than kmsg_bytes, this can never happen,
425 * and if our buffer is smaller than kmsg_bytes, we don't want the
426 * report split across multiple records.
427 */
428 if (record->part != 1)
429 return -ENOSPC;
430
431 if (!cxt->dprzs)
432 return -ENOSPC;
433
434 prz = cxt->dprzs[cxt->dump_write_cnt];
435
436 /*
437 * Since this is a new crash dump, we need to reset the buffer in
438 * case it still has an old dump present. Without this, the new dump
439 * will get appended, which would seriously confuse anything trying
440 * to check dump file contents. Specifically, ramoops_read_kmsg_hdr()
441 * expects to find a dump header in the beginning of buffer data, so
442 * we must to reset the buffer values, in order to ensure that the
443 * header will be written to the beginning of the buffer.
444 */
445 persistent_ram_zap(prz);
446
447 /* Build header and append record contents. */
448 hlen = ramoops_write_kmsg_hdr(prz, record);
449 size = record->size;
450 if (size + hlen > prz->buffer_size)
451 size = prz->buffer_size - hlen;
452 persistent_ram_write(prz, record->buf, size);
453
454 cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
455
456 return 0;
457 }
458
ramoops_pstore_write_user(struct pstore_record * record,const char __user * buf)459 static int notrace ramoops_pstore_write_user(struct pstore_record *record,
460 const char __user *buf)
461 {
462 if (record->type == PSTORE_TYPE_PMSG) {
463 struct ramoops_context *cxt = record->psi->data;
464
465 if (!cxt->mprz)
466 return -ENOMEM;
467 return persistent_ram_write_user(cxt->mprz, buf, record->size);
468 }
469
470 return -EINVAL;
471 }
472
ramoops_pstore_erase(struct pstore_record * record)473 static int ramoops_pstore_erase(struct pstore_record *record)
474 {
475 struct ramoops_context *cxt = record->psi->data;
476 struct persistent_ram_zone *prz;
477
478 switch (record->type) {
479 case PSTORE_TYPE_DMESG:
480 if (record->id >= cxt->max_dump_cnt)
481 return -EINVAL;
482 prz = cxt->dprzs[record->id];
483 break;
484 case PSTORE_TYPE_CONSOLE:
485 prz = cxt->cprz;
486 break;
487 case PSTORE_TYPE_FTRACE:
488 if (record->id >= cxt->max_ftrace_cnt)
489 return -EINVAL;
490 prz = cxt->fprzs[record->id];
491 break;
492 case PSTORE_TYPE_PMSG:
493 prz = cxt->mprz;
494 break;
495 default:
496 return -EINVAL;
497 }
498
499 persistent_ram_free_old(prz);
500 persistent_ram_zap(prz);
501
502 return 0;
503 }
504
505 static struct ramoops_context oops_cxt = {
506 .pstore = {
507 .owner = THIS_MODULE,
508 .name = "ramoops",
509 .open = ramoops_pstore_open,
510 .read = ramoops_pstore_read,
511 .write = ramoops_pstore_write,
512 .write_user = ramoops_pstore_write_user,
513 .erase = ramoops_pstore_erase,
514 },
515 };
516
ramoops_free_przs(struct ramoops_context * cxt)517 static void ramoops_free_przs(struct ramoops_context *cxt)
518 {
519 int i;
520
521 /* Free dump PRZs */
522 if (cxt->dprzs) {
523 for (i = 0; i < cxt->max_dump_cnt; i++)
524 persistent_ram_free(cxt->dprzs[i]);
525
526 kfree(cxt->dprzs);
527 cxt->max_dump_cnt = 0;
528 }
529
530 /* Free ftrace PRZs */
531 if (cxt->fprzs) {
532 for (i = 0; i < cxt->max_ftrace_cnt; i++)
533 persistent_ram_free(cxt->fprzs[i]);
534 kfree(cxt->fprzs);
535 cxt->max_ftrace_cnt = 0;
536 }
537 }
538
ramoops_init_przs(const char * name,struct device * dev,struct ramoops_context * cxt,struct persistent_ram_zone *** przs,phys_addr_t * paddr,size_t mem_sz,ssize_t record_size,unsigned int * cnt,u32 sig,u32 flags)539 static int ramoops_init_przs(const char *name,
540 struct device *dev, struct ramoops_context *cxt,
541 struct persistent_ram_zone ***przs,
542 phys_addr_t *paddr, size_t mem_sz,
543 ssize_t record_size,
544 unsigned int *cnt, u32 sig, u32 flags)
545 {
546 int err = -ENOMEM;
547 int i;
548 size_t zone_sz;
549 struct persistent_ram_zone **prz_ar;
550
551 /* Allocate nothing for 0 mem_sz or 0 record_size. */
552 if (mem_sz == 0 || record_size == 0) {
553 *cnt = 0;
554 return 0;
555 }
556
557 /*
558 * If we have a negative record size, calculate it based on
559 * mem_sz / *cnt. If we have a positive record size, calculate
560 * cnt from mem_sz / record_size.
561 */
562 if (record_size < 0) {
563 if (*cnt == 0)
564 return 0;
565 record_size = mem_sz / *cnt;
566 if (record_size == 0) {
567 dev_err(dev, "%s record size == 0 (%zu / %u)\n",
568 name, mem_sz, *cnt);
569 goto fail;
570 }
571 } else {
572 *cnt = mem_sz / record_size;
573 if (*cnt == 0) {
574 dev_err(dev, "%s record count == 0 (%zu / %zu)\n",
575 name, mem_sz, record_size);
576 goto fail;
577 }
578 }
579
580 if (*paddr + mem_sz - cxt->phys_addr > cxt->size) {
581 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
582 name,
583 mem_sz, (unsigned long long)*paddr,
584 cxt->size, (unsigned long long)cxt->phys_addr);
585 goto fail;
586 }
587
588 zone_sz = mem_sz / *cnt;
589 if (!zone_sz) {
590 dev_err(dev, "%s zone size == 0\n", name);
591 goto fail;
592 }
593
594 prz_ar = kcalloc(*cnt, sizeof(**przs), GFP_KERNEL);
595 if (!prz_ar)
596 goto fail;
597
598 for (i = 0; i < *cnt; i++) {
599 prz_ar[i] = persistent_ram_new(*paddr, zone_sz, sig,
600 &cxt->ecc_info,
601 cxt->memtype, flags);
602 if (IS_ERR(prz_ar[i])) {
603 err = PTR_ERR(prz_ar[i]);
604 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
605 name, record_size,
606 (unsigned long long)*paddr, err);
607
608 while (i > 0) {
609 i--;
610 persistent_ram_free(prz_ar[i]);
611 }
612 kfree(prz_ar);
613 goto fail;
614 }
615 *paddr += zone_sz;
616 }
617
618 *przs = prz_ar;
619 return 0;
620
621 fail:
622 *cnt = 0;
623 return err;
624 }
625
ramoops_init_prz(const char * name,struct device * dev,struct ramoops_context * cxt,struct persistent_ram_zone ** prz,phys_addr_t * paddr,size_t sz,u32 sig)626 static int ramoops_init_prz(const char *name,
627 struct device *dev, struct ramoops_context *cxt,
628 struct persistent_ram_zone **prz,
629 phys_addr_t *paddr, size_t sz, u32 sig)
630 {
631 if (!sz)
632 return 0;
633
634 if (*paddr + sz - cxt->phys_addr > cxt->size) {
635 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
636 name, sz, (unsigned long long)*paddr,
637 cxt->size, (unsigned long long)cxt->phys_addr);
638 return -ENOMEM;
639 }
640
641 *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info,
642 cxt->memtype, 0);
643 if (IS_ERR(*prz)) {
644 int err = PTR_ERR(*prz);
645
646 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
647 name, sz, (unsigned long long)*paddr, err);
648 return err;
649 }
650
651 persistent_ram_zap(*prz);
652
653 *paddr += sz;
654
655 return 0;
656 }
657
ramoops_parse_dt_size(struct platform_device * pdev,const char * propname,u32 * value)658 static int ramoops_parse_dt_size(struct platform_device *pdev,
659 const char *propname, u32 *value)
660 {
661 u32 val32 = 0;
662 int ret;
663
664 ret = of_property_read_u32(pdev->dev.of_node, propname, &val32);
665 if (ret < 0 && ret != -EINVAL) {
666 dev_err(&pdev->dev, "failed to parse property %s: %d\n",
667 propname, ret);
668 return ret;
669 }
670
671 if (val32 > INT_MAX) {
672 dev_err(&pdev->dev, "%s %u > INT_MAX\n", propname, val32);
673 return -EOVERFLOW;
674 }
675
676 *value = val32;
677 return 0;
678 }
679
ramoops_parse_dt(struct platform_device * pdev,struct ramoops_platform_data * pdata)680 static int ramoops_parse_dt(struct platform_device *pdev,
681 struct ramoops_platform_data *pdata)
682 {
683 struct device_node *of_node = pdev->dev.of_node;
684 struct resource *res;
685 u32 value;
686 int ret;
687
688 dev_dbg(&pdev->dev, "using Device Tree\n");
689
690 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
691 if (!res) {
692 dev_err(&pdev->dev,
693 "failed to locate DT /reserved-memory resource\n");
694 return -EINVAL;
695 }
696
697 pdata->mem_size = resource_size(res);
698 pdata->mem_address = res->start;
699 pdata->mem_type = of_property_read_bool(of_node, "unbuffered");
700 pdata->dump_oops = !of_property_read_bool(of_node, "no-dump-oops");
701
702 #define parse_size(name, field) { \
703 ret = ramoops_parse_dt_size(pdev, name, &value); \
704 if (ret < 0) \
705 return ret; \
706 field = value; \
707 }
708
709 parse_size("record-size", pdata->record_size);
710 parse_size("console-size", pdata->console_size);
711 parse_size("ftrace-size", pdata->ftrace_size);
712 parse_size("pmsg-size", pdata->pmsg_size);
713 parse_size("ecc-size", pdata->ecc_info.ecc_size);
714 parse_size("flags", pdata->flags);
715
716 #undef parse_size
717
718 return 0;
719 }
720
ramoops_console_write_buf(const char * buf,size_t size)721 void notrace ramoops_console_write_buf(const char *buf, size_t size)
722 {
723 struct ramoops_context *cxt = &oops_cxt;
724 persistent_ram_write(cxt->cprz, buf, size);
725 }
726
ramoops_probe(struct platform_device * pdev)727 static int ramoops_probe(struct platform_device *pdev)
728 {
729 struct device *dev = &pdev->dev;
730 struct ramoops_platform_data *pdata = dev->platform_data;
731 struct ramoops_platform_data pdata_local;
732 struct ramoops_context *cxt = &oops_cxt;
733 size_t dump_mem_sz;
734 phys_addr_t paddr;
735 int err = -EINVAL;
736
737 if (dev_of_node(dev) && !pdata) {
738 pdata = &pdata_local;
739 memset(pdata, 0, sizeof(*pdata));
740
741 err = ramoops_parse_dt(pdev, pdata);
742 if (err < 0)
743 goto fail_out;
744 }
745
746 /*
747 * Only a single ramoops area allowed at a time, so fail extra
748 * probes.
749 */
750 if (cxt->max_dump_cnt) {
751 pr_err("already initialized\n");
752 goto fail_out;
753 }
754
755 /* Make sure we didn't get bogus platform data pointer. */
756 if (!pdata) {
757 pr_err("NULL platform data\n");
758 goto fail_out;
759 }
760
761 if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
762 !pdata->ftrace_size && !pdata->pmsg_size)) {
763 pr_err("The memory size and the record/console size must be "
764 "non-zero\n");
765 goto fail_out;
766 }
767
768 if (pdata->record_size && !is_power_of_2(pdata->record_size))
769 pdata->record_size = rounddown_pow_of_two(pdata->record_size);
770 if (pdata->console_size && !is_power_of_2(pdata->console_size))
771 pdata->console_size = rounddown_pow_of_two(pdata->console_size);
772 if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))
773 pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);
774 if (pdata->pmsg_size && !is_power_of_2(pdata->pmsg_size))
775 pdata->pmsg_size = rounddown_pow_of_two(pdata->pmsg_size);
776
777 cxt->size = pdata->mem_size;
778 cxt->phys_addr = pdata->mem_address;
779 cxt->memtype = pdata->mem_type;
780 cxt->record_size = pdata->record_size;
781 cxt->console_size = pdata->console_size;
782 cxt->ftrace_size = pdata->ftrace_size;
783 cxt->pmsg_size = pdata->pmsg_size;
784 cxt->dump_oops = pdata->dump_oops;
785 cxt->flags = pdata->flags;
786 cxt->ecc_info = pdata->ecc_info;
787
788 paddr = cxt->phys_addr;
789
790 dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size
791 - cxt->pmsg_size;
792 err = ramoops_init_przs("dump", dev, cxt, &cxt->dprzs, &paddr,
793 dump_mem_sz, cxt->record_size,
794 &cxt->max_dump_cnt, 0, 0);
795 if (err)
796 goto fail_out;
797
798 err = ramoops_init_prz("console", dev, cxt, &cxt->cprz, &paddr,
799 cxt->console_size, 0);
800 if (err)
801 goto fail_init_cprz;
802
803 cxt->max_ftrace_cnt = (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)
804 ? nr_cpu_ids
805 : 1;
806 err = ramoops_init_przs("ftrace", dev, cxt, &cxt->fprzs, &paddr,
807 cxt->ftrace_size, -1,
808 &cxt->max_ftrace_cnt, LINUX_VERSION_CODE,
809 (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)
810 ? PRZ_FLAG_NO_LOCK : 0);
811 if (err)
812 goto fail_init_fprz;
813
814 err = ramoops_init_prz("pmsg", dev, cxt, &cxt->mprz, &paddr,
815 cxt->pmsg_size, 0);
816 if (err)
817 goto fail_init_mprz;
818
819 cxt->pstore.data = cxt;
820 /*
821 * Prepare frontend flags based on which areas are initialized.
822 * For ramoops_init_przs() cases, the "max count" variable tells
823 * if there are regions present. For ramoops_init_prz() cases,
824 * the single region size is how to check.
825 */
826 cxt->pstore.flags = 0;
827 if (cxt->max_dump_cnt)
828 cxt->pstore.flags |= PSTORE_FLAGS_DMESG;
829 if (cxt->console_size)
830 cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE;
831 if (cxt->max_ftrace_cnt)
832 cxt->pstore.flags |= PSTORE_FLAGS_FTRACE;
833 if (cxt->pmsg_size)
834 cxt->pstore.flags |= PSTORE_FLAGS_PMSG;
835
836 /*
837 * Since bufsize is only used for dmesg crash dumps, it
838 * must match the size of the dprz record (after PRZ header
839 * and ECC bytes have been accounted for).
840 */
841 if (cxt->pstore.flags & PSTORE_FLAGS_DMESG) {
842 cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size;
843 cxt->pstore.buf = kzalloc(cxt->pstore.bufsize, GFP_KERNEL);
844 if (!cxt->pstore.buf) {
845 pr_err("cannot allocate pstore crash dump buffer\n");
846 err = -ENOMEM;
847 goto fail_clear;
848 }
849 }
850
851 err = pstore_register(&cxt->pstore);
852 if (err) {
853 pr_err("registering with pstore failed\n");
854 goto fail_buf;
855 }
856
857 /*
858 * Update the module parameter variables as well so they are visible
859 * through /sys/module/ramoops/parameters/
860 */
861 mem_size = pdata->mem_size;
862 mem_address = pdata->mem_address;
863 record_size = pdata->record_size;
864 dump_oops = pdata->dump_oops;
865 ramoops_console_size = pdata->console_size;
866 ramoops_pmsg_size = pdata->pmsg_size;
867 ramoops_ftrace_size = pdata->ftrace_size;
868
869 pr_info("attached 0x%lx@0x%llx, ecc: %d/%d\n",
870 cxt->size, (unsigned long long)cxt->phys_addr,
871 cxt->ecc_info.ecc_size, cxt->ecc_info.block_size);
872
873 return 0;
874
875 fail_buf:
876 kfree(cxt->pstore.buf);
877 fail_clear:
878 cxt->pstore.bufsize = 0;
879 persistent_ram_free(cxt->mprz);
880 fail_init_mprz:
881 fail_init_fprz:
882 persistent_ram_free(cxt->cprz);
883 fail_init_cprz:
884 ramoops_free_przs(cxt);
885 fail_out:
886 return err;
887 }
888
ramoops_remove(struct platform_device * pdev)889 static int ramoops_remove(struct platform_device *pdev)
890 {
891 struct ramoops_context *cxt = &oops_cxt;
892
893 pstore_unregister(&cxt->pstore);
894
895 kfree(cxt->pstore.buf);
896 cxt->pstore.bufsize = 0;
897
898 persistent_ram_free(cxt->mprz);
899 persistent_ram_free(cxt->cprz);
900 ramoops_free_przs(cxt);
901
902 return 0;
903 }
904
905 static const struct of_device_id dt_match[] = {
906 { .compatible = "ramoops" },
907 {}
908 };
909
910 static struct platform_driver ramoops_driver = {
911 .probe = ramoops_probe,
912 .remove = ramoops_remove,
913 .driver = {
914 .name = "ramoops",
915 .of_match_table = dt_match,
916 },
917 };
918
ramoops_register_dummy(void)919 static void ramoops_register_dummy(void)
920 {
921 if (!mem_size)
922 return;
923
924 pr_info("using module parameters\n");
925
926 dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
927 if (!dummy_data) {
928 pr_info("could not allocate pdata\n");
929 return;
930 }
931
932 dummy_data->mem_size = mem_size;
933 dummy_data->mem_address = mem_address;
934 dummy_data->mem_type = mem_type;
935 dummy_data->record_size = record_size;
936 dummy_data->console_size = ramoops_console_size;
937 dummy_data->ftrace_size = ramoops_ftrace_size;
938 dummy_data->pmsg_size = ramoops_pmsg_size;
939 dummy_data->dump_oops = dump_oops;
940 dummy_data->flags = RAMOOPS_FLAG_FTRACE_PER_CPU;
941
942 /*
943 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
944 * (using 1 byte for ECC isn't much of use anyway).
945 */
946 dummy_data->ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc;
947
948 dummy = platform_device_register_data(NULL, "ramoops", -1,
949 dummy_data, sizeof(struct ramoops_platform_data));
950 if (IS_ERR(dummy)) {
951 pr_info("could not create platform device: %ld\n",
952 PTR_ERR(dummy));
953 }
954 }
955
ramoops_init(void)956 static int __init ramoops_init(void)
957 {
958 ramoops_register_dummy();
959 return platform_driver_register(&ramoops_driver);
960 }
961 postcore_initcall(ramoops_init);
962
ramoops_exit(void)963 static void __exit ramoops_exit(void)
964 {
965 platform_driver_unregister(&ramoops_driver);
966 platform_device_unregister(dummy);
967 kfree(dummy_data);
968 }
969 module_exit(ramoops_exit);
970
971 MODULE_LICENSE("GPL");
972 MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
973 MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");
974