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 timespec64 * time,bool * compressed)156 static int ramoops_read_kmsg_hdr(char *buffer, struct timespec64 *time,
157 bool *compressed)
158 {
159 char data_type;
160 int header_length = 0;
161
162 if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu-%c\n%n",
163 (time64_t *)&time->tv_sec, &time->tv_nsec, &data_type,
164 &header_length) == 3) {
165 time->tv_nsec *= 1000;
166 if (data_type == 'C')
167 *compressed = true;
168 else
169 *compressed = false;
170 } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu\n%n",
171 (time64_t *)&time->tv_sec, &time->tv_nsec,
172 &header_length) == 2) {
173 time->tv_nsec *= 1000;
174 *compressed = false;
175 } else {
176 time->tv_sec = 0;
177 time->tv_nsec = 0;
178 *compressed = false;
179 }
180 return header_length;
181 }
182
prz_ok(struct persistent_ram_zone * prz)183 static bool prz_ok(struct persistent_ram_zone *prz)
184 {
185 return !!prz && !!(persistent_ram_old_size(prz) +
186 persistent_ram_ecc_string(prz, NULL, 0));
187 }
188
ftrace_log_combine(struct persistent_ram_zone * dest,struct persistent_ram_zone * src)189 static ssize_t ftrace_log_combine(struct persistent_ram_zone *dest,
190 struct persistent_ram_zone *src)
191 {
192 size_t dest_size, src_size, total, dest_off, src_off;
193 size_t dest_idx = 0, src_idx = 0, merged_idx = 0;
194 void *merged_buf;
195 struct pstore_ftrace_record *drec, *srec, *mrec;
196 size_t record_size = sizeof(struct pstore_ftrace_record);
197
198 dest_off = dest->old_log_size % record_size;
199 dest_size = dest->old_log_size - dest_off;
200
201 src_off = src->old_log_size % record_size;
202 src_size = src->old_log_size - src_off;
203
204 total = dest_size + src_size;
205 merged_buf = kmalloc(total, GFP_KERNEL);
206 if (!merged_buf)
207 return -ENOMEM;
208
209 drec = (struct pstore_ftrace_record *)(dest->old_log + dest_off);
210 srec = (struct pstore_ftrace_record *)(src->old_log + src_off);
211 mrec = (struct pstore_ftrace_record *)(merged_buf);
212
213 while (dest_size > 0 && src_size > 0) {
214 if (pstore_ftrace_read_timestamp(&drec[dest_idx]) <
215 pstore_ftrace_read_timestamp(&srec[src_idx])) {
216 mrec[merged_idx++] = drec[dest_idx++];
217 dest_size -= record_size;
218 } else {
219 mrec[merged_idx++] = srec[src_idx++];
220 src_size -= record_size;
221 }
222 }
223
224 while (dest_size > 0) {
225 mrec[merged_idx++] = drec[dest_idx++];
226 dest_size -= record_size;
227 }
228
229 while (src_size > 0) {
230 mrec[merged_idx++] = srec[src_idx++];
231 src_size -= record_size;
232 }
233
234 kfree(dest->old_log);
235 dest->old_log = merged_buf;
236 dest->old_log_size = total;
237
238 return 0;
239 }
240
ramoops_pstore_read(struct pstore_record * record)241 static ssize_t ramoops_pstore_read(struct pstore_record *record)
242 {
243 ssize_t size = 0;
244 struct ramoops_context *cxt = record->psi->data;
245 struct persistent_ram_zone *prz = NULL;
246 int header_length = 0;
247 bool free_prz = false;
248
249 /*
250 * Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but
251 * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have
252 * valid time stamps, so it is initialized to zero.
253 */
254 record->time.tv_sec = 0;
255 record->time.tv_nsec = 0;
256 record->compressed = false;
257
258 /* Find the next valid persistent_ram_zone for DMESG */
259 while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) {
260 prz = ramoops_get_next_prz(cxt->dprzs, &cxt->dump_read_cnt,
261 cxt->max_dump_cnt, &record->id,
262 &record->type,
263 PSTORE_TYPE_DMESG, 1);
264 if (!prz_ok(prz))
265 continue;
266 header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz),
267 &record->time,
268 &record->compressed);
269 /* Clear and skip this DMESG record if it has no valid header */
270 if (!header_length) {
271 persistent_ram_free_old(prz);
272 persistent_ram_zap(prz);
273 prz = NULL;
274 }
275 }
276
277 if (!prz_ok(prz))
278 prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
279 1, &record->id, &record->type,
280 PSTORE_TYPE_CONSOLE, 0);
281
282 if (!prz_ok(prz))
283 prz = ramoops_get_next_prz(&cxt->mprz, &cxt->pmsg_read_cnt,
284 1, &record->id, &record->type,
285 PSTORE_TYPE_PMSG, 0);
286
287 /* ftrace is last since it may want to dynamically allocate memory. */
288 if (!prz_ok(prz)) {
289 if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)) {
290 prz = ramoops_get_next_prz(cxt->fprzs,
291 &cxt->ftrace_read_cnt, 1, &record->id,
292 &record->type, PSTORE_TYPE_FTRACE, 0);
293 } else {
294 /*
295 * Build a new dummy record which combines all the
296 * per-cpu records including metadata and ecc info.
297 */
298 struct persistent_ram_zone *tmp_prz, *prz_next;
299
300 tmp_prz = kzalloc(sizeof(struct persistent_ram_zone),
301 GFP_KERNEL);
302 if (!tmp_prz)
303 return -ENOMEM;
304 prz = tmp_prz;
305 free_prz = true;
306
307 while (cxt->ftrace_read_cnt < cxt->max_ftrace_cnt) {
308 prz_next = ramoops_get_next_prz(cxt->fprzs,
309 &cxt->ftrace_read_cnt,
310 cxt->max_ftrace_cnt,
311 &record->id,
312 &record->type,
313 PSTORE_TYPE_FTRACE, 0);
314
315 if (!prz_ok(prz_next))
316 continue;
317
318 tmp_prz->ecc_info = prz_next->ecc_info;
319 tmp_prz->corrected_bytes +=
320 prz_next->corrected_bytes;
321 tmp_prz->bad_blocks += prz_next->bad_blocks;
322 size = ftrace_log_combine(tmp_prz, prz_next);
323 if (size)
324 goto out;
325 }
326 record->id = 0;
327 }
328 }
329
330 if (!prz_ok(prz)) {
331 size = 0;
332 goto out;
333 }
334
335 size = persistent_ram_old_size(prz) - header_length;
336
337 /* ECC correction notice */
338 record->ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
339
340 record->buf = kmalloc(size + record->ecc_notice_size + 1, GFP_KERNEL);
341 if (record->buf == NULL) {
342 size = -ENOMEM;
343 goto out;
344 }
345
346 memcpy(record->buf, (char *)persistent_ram_old(prz) + header_length,
347 size);
348
349 persistent_ram_ecc_string(prz, record->buf + size,
350 record->ecc_notice_size + 1);
351
352 out:
353 if (free_prz) {
354 kfree(prz->old_log);
355 kfree(prz);
356 }
357
358 return size;
359 }
360
ramoops_write_kmsg_hdr(struct persistent_ram_zone * prz,struct pstore_record * record)361 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
362 struct pstore_record *record)
363 {
364 char *hdr;
365 size_t len;
366
367 hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lld.%06lu-%c\n",
368 (time64_t)record->time.tv_sec,
369 record->time.tv_nsec / 1000,
370 record->compressed ? 'C' : 'D');
371 WARN_ON_ONCE(!hdr);
372 len = hdr ? strlen(hdr) : 0;
373 persistent_ram_write(prz, hdr, len);
374 kfree(hdr);
375
376 return len;
377 }
378
ramoops_pstore_write(struct pstore_record * record)379 static int notrace ramoops_pstore_write(struct pstore_record *record)
380 {
381 struct ramoops_context *cxt = record->psi->data;
382 struct persistent_ram_zone *prz;
383 size_t size, hlen;
384
385 if (record->type == PSTORE_TYPE_CONSOLE) {
386 if (!cxt->cprz)
387 return -ENOMEM;
388 persistent_ram_write(cxt->cprz, record->buf, record->size);
389 return 0;
390 } else if (record->type == PSTORE_TYPE_FTRACE) {
391 int zonenum;
392
393 if (!cxt->fprzs)
394 return -ENOMEM;
395 /*
396 * Choose zone by if we're using per-cpu buffers.
397 */
398 if (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)
399 zonenum = smp_processor_id();
400 else
401 zonenum = 0;
402
403 persistent_ram_write(cxt->fprzs[zonenum], record->buf,
404 record->size);
405 return 0;
406 } else if (record->type == PSTORE_TYPE_PMSG) {
407 pr_warn_ratelimited("PMSG shouldn't call %s\n", __func__);
408 return -EINVAL;
409 }
410
411 if (record->type != PSTORE_TYPE_DMESG)
412 return -EINVAL;
413
414 /*
415 * Out of the various dmesg dump types, ramoops is currently designed
416 * to only store crash logs, rather than storing general kernel logs.
417 */
418 if (record->reason != KMSG_DUMP_OOPS &&
419 record->reason != KMSG_DUMP_PANIC)
420 return -EINVAL;
421
422 /* Skip Oopes when configured to do so. */
423 if (record->reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
424 return -EINVAL;
425
426 /*
427 * Explicitly only take the first part of any new crash.
428 * If our buffer is larger than kmsg_bytes, this can never happen,
429 * and if our buffer is smaller than kmsg_bytes, we don't want the
430 * report split across multiple records.
431 */
432 if (record->part != 1)
433 return -ENOSPC;
434
435 if (!cxt->dprzs)
436 return -ENOSPC;
437
438 prz = cxt->dprzs[cxt->dump_write_cnt];
439
440 /*
441 * Since this is a new crash dump, we need to reset the buffer in
442 * case it still has an old dump present. Without this, the new dump
443 * will get appended, which would seriously confuse anything trying
444 * to check dump file contents. Specifically, ramoops_read_kmsg_hdr()
445 * expects to find a dump header in the beginning of buffer data, so
446 * we must to reset the buffer values, in order to ensure that the
447 * header will be written to the beginning of the buffer.
448 */
449 persistent_ram_zap(prz);
450
451 /* Build header and append record contents. */
452 hlen = ramoops_write_kmsg_hdr(prz, record);
453 size = record->size;
454 if (size + hlen > prz->buffer_size)
455 size = prz->buffer_size - hlen;
456 persistent_ram_write(prz, record->buf, size);
457
458 cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
459
460 return 0;
461 }
462
ramoops_pstore_write_user(struct pstore_record * record,const char __user * buf)463 static int notrace ramoops_pstore_write_user(struct pstore_record *record,
464 const char __user *buf)
465 {
466 if (record->type == PSTORE_TYPE_PMSG) {
467 struct ramoops_context *cxt = record->psi->data;
468
469 if (!cxt->mprz)
470 return -ENOMEM;
471 return persistent_ram_write_user(cxt->mprz, buf, record->size);
472 }
473
474 return -EINVAL;
475 }
476
ramoops_pstore_erase(struct pstore_record * record)477 static int ramoops_pstore_erase(struct pstore_record *record)
478 {
479 struct ramoops_context *cxt = record->psi->data;
480 struct persistent_ram_zone *prz;
481
482 switch (record->type) {
483 case PSTORE_TYPE_DMESG:
484 if (record->id >= cxt->max_dump_cnt)
485 return -EINVAL;
486 prz = cxt->dprzs[record->id];
487 break;
488 case PSTORE_TYPE_CONSOLE:
489 prz = cxt->cprz;
490 break;
491 case PSTORE_TYPE_FTRACE:
492 if (record->id >= cxt->max_ftrace_cnt)
493 return -EINVAL;
494 prz = cxt->fprzs[record->id];
495 break;
496 case PSTORE_TYPE_PMSG:
497 prz = cxt->mprz;
498 break;
499 default:
500 return -EINVAL;
501 }
502
503 persistent_ram_free_old(prz);
504 persistent_ram_zap(prz);
505
506 return 0;
507 }
508
509 static struct ramoops_context oops_cxt = {
510 .pstore = {
511 .owner = THIS_MODULE,
512 .name = "ramoops",
513 .open = ramoops_pstore_open,
514 .read = ramoops_pstore_read,
515 .write = ramoops_pstore_write,
516 .write_user = ramoops_pstore_write_user,
517 .erase = ramoops_pstore_erase,
518 },
519 };
520
ramoops_free_przs(struct ramoops_context * cxt)521 static void ramoops_free_przs(struct ramoops_context *cxt)
522 {
523 int i;
524
525 /* Free dump PRZs */
526 if (cxt->dprzs) {
527 for (i = 0; i < cxt->max_dump_cnt; i++)
528 persistent_ram_free(cxt->dprzs[i]);
529
530 kfree(cxt->dprzs);
531 cxt->max_dump_cnt = 0;
532 }
533
534 /* Free ftrace PRZs */
535 if (cxt->fprzs) {
536 for (i = 0; i < cxt->max_ftrace_cnt; i++)
537 persistent_ram_free(cxt->fprzs[i]);
538 kfree(cxt->fprzs);
539 cxt->max_ftrace_cnt = 0;
540 }
541 }
542
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)543 static int ramoops_init_przs(const char *name,
544 struct device *dev, struct ramoops_context *cxt,
545 struct persistent_ram_zone ***przs,
546 phys_addr_t *paddr, size_t mem_sz,
547 ssize_t record_size,
548 unsigned int *cnt, u32 sig, u32 flags)
549 {
550 int err = -ENOMEM;
551 int i;
552 size_t zone_sz;
553 struct persistent_ram_zone **prz_ar;
554
555 /* Allocate nothing for 0 mem_sz or 0 record_size. */
556 if (mem_sz == 0 || record_size == 0) {
557 *cnt = 0;
558 return 0;
559 }
560
561 /*
562 * If we have a negative record size, calculate it based on
563 * mem_sz / *cnt. If we have a positive record size, calculate
564 * cnt from mem_sz / record_size.
565 */
566 if (record_size < 0) {
567 if (*cnt == 0)
568 return 0;
569 record_size = mem_sz / *cnt;
570 if (record_size == 0) {
571 dev_err(dev, "%s record size == 0 (%zu / %u)\n",
572 name, mem_sz, *cnt);
573 goto fail;
574 }
575 } else {
576 *cnt = mem_sz / record_size;
577 if (*cnt == 0) {
578 dev_err(dev, "%s record count == 0 (%zu / %zu)\n",
579 name, mem_sz, record_size);
580 goto fail;
581 }
582 }
583
584 if (*paddr + mem_sz - cxt->phys_addr > cxt->size) {
585 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
586 name,
587 mem_sz, (unsigned long long)*paddr,
588 cxt->size, (unsigned long long)cxt->phys_addr);
589 goto fail;
590 }
591
592 zone_sz = mem_sz / *cnt;
593 if (!zone_sz) {
594 dev_err(dev, "%s zone size == 0\n", name);
595 goto fail;
596 }
597
598 prz_ar = kcalloc(*cnt, sizeof(**przs), GFP_KERNEL);
599 if (!prz_ar)
600 goto fail;
601
602 for (i = 0; i < *cnt; i++) {
603 prz_ar[i] = persistent_ram_new(*paddr, zone_sz, sig,
604 &cxt->ecc_info,
605 cxt->memtype, flags);
606 if (IS_ERR(prz_ar[i])) {
607 err = PTR_ERR(prz_ar[i]);
608 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
609 name, record_size,
610 (unsigned long long)*paddr, err);
611
612 while (i > 0) {
613 i--;
614 persistent_ram_free(prz_ar[i]);
615 }
616 kfree(prz_ar);
617 goto fail;
618 }
619 *paddr += zone_sz;
620 }
621
622 *przs = prz_ar;
623 return 0;
624
625 fail:
626 *cnt = 0;
627 return err;
628 }
629
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)630 static int ramoops_init_prz(const char *name,
631 struct device *dev, struct ramoops_context *cxt,
632 struct persistent_ram_zone **prz,
633 phys_addr_t *paddr, size_t sz, u32 sig)
634 {
635 if (!sz)
636 return 0;
637
638 if (*paddr + sz - cxt->phys_addr > cxt->size) {
639 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
640 name, sz, (unsigned long long)*paddr,
641 cxt->size, (unsigned long long)cxt->phys_addr);
642 return -ENOMEM;
643 }
644
645 *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info,
646 cxt->memtype, 0);
647 if (IS_ERR(*prz)) {
648 int err = PTR_ERR(*prz);
649
650 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
651 name, sz, (unsigned long long)*paddr, err);
652 return err;
653 }
654
655 persistent_ram_zap(*prz);
656
657 *paddr += sz;
658
659 return 0;
660 }
661
ramoops_parse_dt_size(struct platform_device * pdev,const char * propname,u32 * value)662 static int ramoops_parse_dt_size(struct platform_device *pdev,
663 const char *propname, u32 *value)
664 {
665 u32 val32 = 0;
666 int ret;
667
668 ret = of_property_read_u32(pdev->dev.of_node, propname, &val32);
669 if (ret < 0 && ret != -EINVAL) {
670 dev_err(&pdev->dev, "failed to parse property %s: %d\n",
671 propname, ret);
672 return ret;
673 }
674
675 if (val32 > INT_MAX) {
676 dev_err(&pdev->dev, "%s %u > INT_MAX\n", propname, val32);
677 return -EOVERFLOW;
678 }
679
680 *value = val32;
681 return 0;
682 }
683
ramoops_parse_dt(struct platform_device * pdev,struct ramoops_platform_data * pdata)684 static int ramoops_parse_dt(struct platform_device *pdev,
685 struct ramoops_platform_data *pdata)
686 {
687 struct device_node *of_node = pdev->dev.of_node;
688 struct resource *res;
689 u32 value;
690 int ret;
691
692 dev_dbg(&pdev->dev, "using Device Tree\n");
693
694 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
695 if (!res) {
696 dev_err(&pdev->dev,
697 "failed to locate DT /reserved-memory resource\n");
698 return -EINVAL;
699 }
700
701 pdata->mem_size = resource_size(res);
702 pdata->mem_address = res->start;
703 pdata->mem_type = of_property_read_bool(of_node, "unbuffered");
704 pdata->dump_oops = !of_property_read_bool(of_node, "no-dump-oops");
705
706 #define parse_size(name, field) { \
707 ret = ramoops_parse_dt_size(pdev, name, &value); \
708 if (ret < 0) \
709 return ret; \
710 field = value; \
711 }
712
713 parse_size("record-size", pdata->record_size);
714 parse_size("console-size", pdata->console_size);
715 parse_size("ftrace-size", pdata->ftrace_size);
716 parse_size("pmsg-size", pdata->pmsg_size);
717 parse_size("ecc-size", pdata->ecc_info.ecc_size);
718 parse_size("flags", pdata->flags);
719
720 #undef parse_size
721
722 return 0;
723 }
724
ramoops_probe(struct platform_device * pdev)725 static int ramoops_probe(struct platform_device *pdev)
726 {
727 struct device *dev = &pdev->dev;
728 struct ramoops_platform_data *pdata = dev->platform_data;
729 struct ramoops_platform_data pdata_local;
730 struct ramoops_context *cxt = &oops_cxt;
731 size_t dump_mem_sz;
732 phys_addr_t paddr;
733 int err = -EINVAL;
734
735 if (dev_of_node(dev) && !pdata) {
736 pdata = &pdata_local;
737 memset(pdata, 0, sizeof(*pdata));
738
739 err = ramoops_parse_dt(pdev, pdata);
740 if (err < 0)
741 goto fail_out;
742 }
743
744 /*
745 * Only a single ramoops area allowed at a time, so fail extra
746 * probes.
747 */
748 if (cxt->max_dump_cnt) {
749 pr_err("already initialized\n");
750 goto fail_out;
751 }
752
753 /* Make sure we didn't get bogus platform data pointer. */
754 if (!pdata) {
755 pr_err("NULL platform data\n");
756 err = -EINVAL;
757 goto fail_out;
758 }
759
760 if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
761 !pdata->ftrace_size && !pdata->pmsg_size)) {
762 pr_err("The memory size and the record/console size must be "
763 "non-zero\n");
764 err = -EINVAL;
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_unregister_dummy(void)919 static inline void ramoops_unregister_dummy(void)
920 {
921 platform_device_unregister(dummy);
922 dummy = NULL;
923
924 kfree(dummy_data);
925 dummy_data = NULL;
926 }
927
ramoops_register_dummy(void)928 static void __init ramoops_register_dummy(void)
929 {
930 /*
931 * Prepare a dummy platform data structure to carry the module
932 * parameters. If mem_size isn't set, then there are no module
933 * parameters, and we can skip this.
934 */
935 if (!mem_size)
936 return;
937
938 pr_info("using module parameters\n");
939
940 dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
941 if (!dummy_data) {
942 pr_info("could not allocate pdata\n");
943 return;
944 }
945
946 dummy_data->mem_size = mem_size;
947 dummy_data->mem_address = mem_address;
948 dummy_data->mem_type = mem_type;
949 dummy_data->record_size = record_size;
950 dummy_data->console_size = ramoops_console_size;
951 dummy_data->ftrace_size = ramoops_ftrace_size;
952 dummy_data->pmsg_size = ramoops_pmsg_size;
953 dummy_data->dump_oops = dump_oops;
954 dummy_data->flags = RAMOOPS_FLAG_FTRACE_PER_CPU;
955
956 /*
957 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
958 * (using 1 byte for ECC isn't much of use anyway).
959 */
960 dummy_data->ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc;
961
962 dummy = platform_device_register_data(NULL, "ramoops", -1,
963 dummy_data, sizeof(struct ramoops_platform_data));
964 if (IS_ERR(dummy)) {
965 pr_info("could not create platform device: %ld\n",
966 PTR_ERR(dummy));
967 dummy = NULL;
968 ramoops_unregister_dummy();
969 }
970 }
971
ramoops_init(void)972 static int __init ramoops_init(void)
973 {
974 int ret;
975
976 ramoops_register_dummy();
977 ret = platform_driver_register(&ramoops_driver);
978 if (ret != 0)
979 ramoops_unregister_dummy();
980
981 return ret;
982 }
983 postcore_initcall(ramoops_init);
984
ramoops_exit(void)985 static void __exit ramoops_exit(void)
986 {
987 platform_driver_unregister(&ramoops_driver);
988 ramoops_unregister_dummy();
989 }
990 module_exit(ramoops_exit);
991
992 MODULE_LICENSE("GPL");
993 MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
994 MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");
995