1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * RAM Oops/Panic logger 4 * 5 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com> 6 * Copyright (C) 2011 Kees Cook <keescook@chromium.org> 7 */ 8 9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 10 11 #include <linux/kernel.h> 12 #include <linux/err.h> 13 #include <linux/module.h> 14 #include <linux/version.h> 15 #include <linux/pstore.h> 16 #include <linux/io.h> 17 #include <linux/ioport.h> 18 #include <linux/platform_device.h> 19 #include <linux/slab.h> 20 #include <linux/compiler.h> 21 #include <linux/pstore_ram.h> 22 #include <linux/of.h> 23 #include <linux/of_address.h> 24 #include "internal.h" 25 26 #define RAMOOPS_KERNMSG_HDR "====" 27 #define MIN_MEM_SIZE 4096UL 28 29 static ulong record_size = MIN_MEM_SIZE; 30 module_param(record_size, ulong, 0400); 31 MODULE_PARM_DESC(record_size, 32 "size of each dump done on oops/panic"); 33 34 static ulong ramoops_console_size = MIN_MEM_SIZE; 35 module_param_named(console_size, ramoops_console_size, ulong, 0400); 36 MODULE_PARM_DESC(console_size, "size of kernel console log"); 37 38 static ulong ramoops_ftrace_size = MIN_MEM_SIZE; 39 module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400); 40 MODULE_PARM_DESC(ftrace_size, "size of ftrace log"); 41 42 static ulong ramoops_pmsg_size = MIN_MEM_SIZE; 43 module_param_named(pmsg_size, ramoops_pmsg_size, ulong, 0400); 44 MODULE_PARM_DESC(pmsg_size, "size of user space message log"); 45 46 static unsigned long long mem_address; 47 module_param_hw(mem_address, ullong, other, 0400); 48 MODULE_PARM_DESC(mem_address, 49 "start of reserved RAM used to store oops/panic logs"); 50 51 static ulong mem_size; 52 module_param(mem_size, ulong, 0400); 53 MODULE_PARM_DESC(mem_size, 54 "size of reserved RAM used to store oops/panic logs"); 55 56 static unsigned int mem_type; 57 module_param(mem_type, uint, 0400); 58 MODULE_PARM_DESC(mem_type, 59 "memory type: 0=write-combined (default), 1=unbuffered, 2=cached"); 60 61 static int ramoops_max_reason = -1; 62 module_param_named(max_reason, ramoops_max_reason, int, 0400); 63 MODULE_PARM_DESC(max_reason, 64 "maximum reason for kmsg dump (default 2: Oops and Panic) "); 65 66 static int ramoops_ecc; 67 module_param_named(ecc, ramoops_ecc, int, 0400); 68 MODULE_PARM_DESC(ramoops_ecc, 69 "if non-zero, the option enables ECC support and specifies " 70 "ECC buffer size in bytes (1 is a special value, means 16 " 71 "bytes ECC)"); 72 73 static int ramoops_dump_oops = -1; 74 module_param_named(dump_oops, ramoops_dump_oops, int, 0400); 75 MODULE_PARM_DESC(dump_oops, 76 "(deprecated: use max_reason instead) set to 1 to dump oopses & panics, 0 to only dump panics"); 77 78 struct ramoops_context { 79 struct persistent_ram_zone **dprzs; /* Oops dump zones */ 80 struct persistent_ram_zone *cprz; /* Console zone */ 81 struct persistent_ram_zone **fprzs; /* Ftrace zones */ 82 struct persistent_ram_zone *mprz; /* PMSG zone */ 83 phys_addr_t phys_addr; 84 unsigned long size; 85 unsigned int memtype; 86 size_t record_size; 87 size_t console_size; 88 size_t ftrace_size; 89 size_t pmsg_size; 90 u32 flags; 91 struct persistent_ram_ecc_info ecc_info; 92 unsigned int max_dump_cnt; 93 unsigned int dump_write_cnt; 94 /* _read_cnt need clear on ramoops_pstore_open */ 95 unsigned int dump_read_cnt; 96 unsigned int console_read_cnt; 97 unsigned int max_ftrace_cnt; 98 unsigned int ftrace_read_cnt; 99 unsigned int pmsg_read_cnt; 100 struct pstore_info pstore; 101 }; 102 103 static struct platform_device *dummy; 104 105 static int ramoops_pstore_open(struct pstore_info *psi) 106 { 107 struct ramoops_context *cxt = psi->data; 108 109 cxt->dump_read_cnt = 0; 110 cxt->console_read_cnt = 0; 111 cxt->ftrace_read_cnt = 0; 112 cxt->pmsg_read_cnt = 0; 113 return 0; 114 } 115 116 static struct persistent_ram_zone * 117 ramoops_get_next_prz(struct persistent_ram_zone *przs[], int id, 118 struct pstore_record *record) 119 { 120 struct persistent_ram_zone *prz; 121 122 /* Give up if we never existed or have hit the end. */ 123 if (!przs) 124 return NULL; 125 126 prz = przs[id]; 127 if (!prz) 128 return NULL; 129 130 /* Update old/shadowed buffer. */ 131 if (prz->type == PSTORE_TYPE_DMESG) 132 persistent_ram_save_old(prz); 133 134 if (!persistent_ram_old_size(prz)) 135 return NULL; 136 137 record->type = prz->type; 138 record->id = id; 139 140 return prz; 141 } 142 143 static int ramoops_read_kmsg_hdr(char *buffer, struct timespec64 *time, 144 bool *compressed) 145 { 146 char data_type; 147 int header_length = 0; 148 149 if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu-%c\n%n", 150 (time64_t *)&time->tv_sec, &time->tv_nsec, &data_type, 151 &header_length) == 3) { 152 time->tv_nsec *= 1000; 153 if (data_type == 'C') 154 *compressed = true; 155 else 156 *compressed = false; 157 } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu\n%n", 158 (time64_t *)&time->tv_sec, &time->tv_nsec, 159 &header_length) == 2) { 160 time->tv_nsec *= 1000; 161 *compressed = false; 162 } else { 163 time->tv_sec = 0; 164 time->tv_nsec = 0; 165 *compressed = false; 166 } 167 return header_length; 168 } 169 170 static bool prz_ok(struct persistent_ram_zone *prz) 171 { 172 return !!prz && !!(persistent_ram_old_size(prz) + 173 persistent_ram_ecc_string(prz, NULL, 0)); 174 } 175 176 static ssize_t ramoops_pstore_read(struct pstore_record *record) 177 { 178 ssize_t size = 0; 179 struct ramoops_context *cxt = record->psi->data; 180 struct persistent_ram_zone *prz = NULL; 181 int header_length = 0; 182 bool free_prz = false; 183 184 /* 185 * Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but 186 * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have 187 * valid time stamps, so it is initialized to zero. 188 */ 189 record->time.tv_sec = 0; 190 record->time.tv_nsec = 0; 191 record->compressed = false; 192 193 /* Find the next valid persistent_ram_zone for DMESG */ 194 while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) { 195 prz = ramoops_get_next_prz(cxt->dprzs, cxt->dump_read_cnt++, 196 record); 197 if (!prz_ok(prz)) 198 continue; 199 header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz), 200 &record->time, 201 &record->compressed); 202 /* Clear and skip this DMESG record if it has no valid header */ 203 if (!header_length) { 204 persistent_ram_free_old(prz); 205 persistent_ram_zap(prz); 206 prz = NULL; 207 } 208 } 209 210 if (!prz_ok(prz) && !cxt->console_read_cnt++) 211 prz = ramoops_get_next_prz(&cxt->cprz, 0 /* single */, record); 212 213 if (!prz_ok(prz) && !cxt->pmsg_read_cnt++) 214 prz = ramoops_get_next_prz(&cxt->mprz, 0 /* single */, record); 215 216 /* ftrace is last since it may want to dynamically allocate memory. */ 217 if (!prz_ok(prz)) { 218 if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) && 219 !cxt->ftrace_read_cnt++) { 220 prz = ramoops_get_next_prz(cxt->fprzs, 0 /* single */, 221 record); 222 } else { 223 /* 224 * Build a new dummy record which combines all the 225 * per-cpu records including metadata and ecc info. 226 */ 227 struct persistent_ram_zone *tmp_prz, *prz_next; 228 229 tmp_prz = kzalloc(sizeof(struct persistent_ram_zone), 230 GFP_KERNEL); 231 if (!tmp_prz) 232 return -ENOMEM; 233 prz = tmp_prz; 234 free_prz = true; 235 236 while (cxt->ftrace_read_cnt < cxt->max_ftrace_cnt) { 237 prz_next = ramoops_get_next_prz(cxt->fprzs, 238 cxt->ftrace_read_cnt++, record); 239 240 if (!prz_ok(prz_next)) 241 continue; 242 243 tmp_prz->ecc_info = prz_next->ecc_info; 244 tmp_prz->corrected_bytes += 245 prz_next->corrected_bytes; 246 tmp_prz->bad_blocks += prz_next->bad_blocks; 247 248 size = pstore_ftrace_combine_log( 249 &tmp_prz->old_log, 250 &tmp_prz->old_log_size, 251 prz_next->old_log, 252 prz_next->old_log_size); 253 if (size) 254 goto out; 255 } 256 record->id = 0; 257 } 258 } 259 260 if (!prz_ok(prz)) { 261 size = 0; 262 goto out; 263 } 264 265 size = persistent_ram_old_size(prz) - header_length; 266 267 /* ECC correction notice */ 268 record->ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0); 269 270 record->buf = kmalloc(size + record->ecc_notice_size + 1, GFP_KERNEL); 271 if (record->buf == NULL) { 272 size = -ENOMEM; 273 goto out; 274 } 275 276 memcpy(record->buf, (char *)persistent_ram_old(prz) + header_length, 277 size); 278 279 persistent_ram_ecc_string(prz, record->buf + size, 280 record->ecc_notice_size + 1); 281 282 out: 283 if (free_prz) { 284 kfree(prz->old_log); 285 kfree(prz); 286 } 287 288 return size; 289 } 290 291 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz, 292 struct pstore_record *record) 293 { 294 char hdr[36]; /* "===="(4), %lld(20), "."(1), %06lu(6), "-%c\n"(3) */ 295 size_t len; 296 297 len = scnprintf(hdr, sizeof(hdr), 298 RAMOOPS_KERNMSG_HDR "%lld.%06lu-%c\n", 299 (time64_t)record->time.tv_sec, 300 record->time.tv_nsec / 1000, 301 record->compressed ? 'C' : 'D'); 302 persistent_ram_write(prz, hdr, len); 303 304 return len; 305 } 306 307 static int notrace ramoops_pstore_write(struct pstore_record *record) 308 { 309 struct ramoops_context *cxt = record->psi->data; 310 struct persistent_ram_zone *prz; 311 size_t size, hlen; 312 313 if (record->type == PSTORE_TYPE_CONSOLE) { 314 if (!cxt->cprz) 315 return -ENOMEM; 316 persistent_ram_write(cxt->cprz, record->buf, record->size); 317 return 0; 318 } else if (record->type == PSTORE_TYPE_FTRACE) { 319 int zonenum; 320 321 if (!cxt->fprzs) 322 return -ENOMEM; 323 /* 324 * Choose zone by if we're using per-cpu buffers. 325 */ 326 if (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) 327 zonenum = smp_processor_id(); 328 else 329 zonenum = 0; 330 331 persistent_ram_write(cxt->fprzs[zonenum], record->buf, 332 record->size); 333 return 0; 334 } else if (record->type == PSTORE_TYPE_PMSG) { 335 pr_warn_ratelimited("PMSG shouldn't call %s\n", __func__); 336 return -EINVAL; 337 } 338 339 if (record->type != PSTORE_TYPE_DMESG) 340 return -EINVAL; 341 342 /* 343 * We could filter on record->reason here if we wanted to (which 344 * would duplicate what happened before the "max_reason" setting 345 * was added), but that would defeat the purpose of a system 346 * changing printk.always_kmsg_dump, so instead log everything that 347 * the kmsg dumper sends us, since it should be doing the filtering 348 * based on the combination of printk.always_kmsg_dump and our 349 * requested "max_reason". 350 */ 351 352 /* 353 * Explicitly only take the first part of any new crash. 354 * If our buffer is larger than kmsg_bytes, this can never happen, 355 * and if our buffer is smaller than kmsg_bytes, we don't want the 356 * report split across multiple records. 357 */ 358 if (record->part != 1) 359 return -ENOSPC; 360 361 if (!cxt->dprzs) 362 return -ENOSPC; 363 364 prz = cxt->dprzs[cxt->dump_write_cnt]; 365 366 /* 367 * Since this is a new crash dump, we need to reset the buffer in 368 * case it still has an old dump present. Without this, the new dump 369 * will get appended, which would seriously confuse anything trying 370 * to check dump file contents. Specifically, ramoops_read_kmsg_hdr() 371 * expects to find a dump header in the beginning of buffer data, so 372 * we must to reset the buffer values, in order to ensure that the 373 * header will be written to the beginning of the buffer. 374 */ 375 persistent_ram_zap(prz); 376 377 /* Build header and append record contents. */ 378 hlen = ramoops_write_kmsg_hdr(prz, record); 379 if (!hlen) 380 return -ENOMEM; 381 382 size = record->size; 383 if (size + hlen > prz->buffer_size) 384 size = prz->buffer_size - hlen; 385 persistent_ram_write(prz, record->buf, size); 386 387 cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt; 388 389 return 0; 390 } 391 392 static int notrace ramoops_pstore_write_user(struct pstore_record *record, 393 const char __user *buf) 394 { 395 if (record->type == PSTORE_TYPE_PMSG) { 396 struct ramoops_context *cxt = record->psi->data; 397 398 if (!cxt->mprz) 399 return -ENOMEM; 400 return persistent_ram_write_user(cxt->mprz, buf, record->size); 401 } 402 403 return -EINVAL; 404 } 405 406 static int ramoops_pstore_erase(struct pstore_record *record) 407 { 408 struct ramoops_context *cxt = record->psi->data; 409 struct persistent_ram_zone *prz; 410 411 switch (record->type) { 412 case PSTORE_TYPE_DMESG: 413 if (record->id >= cxt->max_dump_cnt) 414 return -EINVAL; 415 prz = cxt->dprzs[record->id]; 416 break; 417 case PSTORE_TYPE_CONSOLE: 418 prz = cxt->cprz; 419 break; 420 case PSTORE_TYPE_FTRACE: 421 if (record->id >= cxt->max_ftrace_cnt) 422 return -EINVAL; 423 prz = cxt->fprzs[record->id]; 424 break; 425 case PSTORE_TYPE_PMSG: 426 prz = cxt->mprz; 427 break; 428 default: 429 return -EINVAL; 430 } 431 432 persistent_ram_free_old(prz); 433 persistent_ram_zap(prz); 434 435 return 0; 436 } 437 438 static struct ramoops_context oops_cxt = { 439 .pstore = { 440 .owner = THIS_MODULE, 441 .name = "ramoops", 442 .open = ramoops_pstore_open, 443 .read = ramoops_pstore_read, 444 .write = ramoops_pstore_write, 445 .write_user = ramoops_pstore_write_user, 446 .erase = ramoops_pstore_erase, 447 }, 448 }; 449 450 static void ramoops_free_przs(struct ramoops_context *cxt) 451 { 452 int i; 453 454 /* Free dump PRZs */ 455 if (cxt->dprzs) { 456 for (i = 0; i < cxt->max_dump_cnt; i++) 457 persistent_ram_free(cxt->dprzs[i]); 458 459 kfree(cxt->dprzs); 460 cxt->max_dump_cnt = 0; 461 } 462 463 /* Free ftrace PRZs */ 464 if (cxt->fprzs) { 465 for (i = 0; i < cxt->max_ftrace_cnt; i++) 466 persistent_ram_free(cxt->fprzs[i]); 467 kfree(cxt->fprzs); 468 cxt->max_ftrace_cnt = 0; 469 } 470 } 471 472 static int ramoops_init_przs(const char *name, 473 struct device *dev, struct ramoops_context *cxt, 474 struct persistent_ram_zone ***przs, 475 phys_addr_t *paddr, size_t mem_sz, 476 ssize_t record_size, 477 unsigned int *cnt, u32 sig, u32 flags) 478 { 479 int err = -ENOMEM; 480 int i; 481 size_t zone_sz; 482 struct persistent_ram_zone **prz_ar; 483 484 /* Allocate nothing for 0 mem_sz or 0 record_size. */ 485 if (mem_sz == 0 || record_size == 0) { 486 *cnt = 0; 487 return 0; 488 } 489 490 /* 491 * If we have a negative record size, calculate it based on 492 * mem_sz / *cnt. If we have a positive record size, calculate 493 * cnt from mem_sz / record_size. 494 */ 495 if (record_size < 0) { 496 if (*cnt == 0) 497 return 0; 498 record_size = mem_sz / *cnt; 499 if (record_size == 0) { 500 dev_err(dev, "%s record size == 0 (%zu / %u)\n", 501 name, mem_sz, *cnt); 502 goto fail; 503 } 504 } else { 505 *cnt = mem_sz / record_size; 506 if (*cnt == 0) { 507 dev_err(dev, "%s record count == 0 (%zu / %zu)\n", 508 name, mem_sz, record_size); 509 goto fail; 510 } 511 } 512 513 if (*paddr + mem_sz - cxt->phys_addr > cxt->size) { 514 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n", 515 name, 516 mem_sz, (unsigned long long)*paddr, 517 cxt->size, (unsigned long long)cxt->phys_addr); 518 goto fail; 519 } 520 521 zone_sz = mem_sz / *cnt; 522 if (!zone_sz) { 523 dev_err(dev, "%s zone size == 0\n", name); 524 goto fail; 525 } 526 527 prz_ar = kcalloc(*cnt, sizeof(**przs), GFP_KERNEL); 528 if (!prz_ar) 529 goto fail; 530 531 for (i = 0; i < *cnt; i++) { 532 char *label; 533 534 if (*cnt == 1) 535 label = kasprintf(GFP_KERNEL, "ramoops:%s", name); 536 else 537 label = kasprintf(GFP_KERNEL, "ramoops:%s(%d/%d)", 538 name, i, *cnt - 1); 539 prz_ar[i] = persistent_ram_new(*paddr, zone_sz, sig, 540 &cxt->ecc_info, 541 cxt->memtype, flags, label); 542 kfree(label); 543 if (IS_ERR(prz_ar[i])) { 544 err = PTR_ERR(prz_ar[i]); 545 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n", 546 name, record_size, 547 (unsigned long long)*paddr, err); 548 549 while (i > 0) { 550 i--; 551 persistent_ram_free(prz_ar[i]); 552 } 553 kfree(prz_ar); 554 goto fail; 555 } 556 *paddr += zone_sz; 557 prz_ar[i]->type = pstore_name_to_type(name); 558 } 559 560 *przs = prz_ar; 561 return 0; 562 563 fail: 564 *cnt = 0; 565 return err; 566 } 567 568 static int ramoops_init_prz(const char *name, 569 struct device *dev, struct ramoops_context *cxt, 570 struct persistent_ram_zone **prz, 571 phys_addr_t *paddr, size_t sz, u32 sig) 572 { 573 char *label; 574 575 if (!sz) 576 return 0; 577 578 if (*paddr + sz - cxt->phys_addr > cxt->size) { 579 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n", 580 name, sz, (unsigned long long)*paddr, 581 cxt->size, (unsigned long long)cxt->phys_addr); 582 return -ENOMEM; 583 } 584 585 label = kasprintf(GFP_KERNEL, "ramoops:%s", name); 586 *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info, 587 cxt->memtype, PRZ_FLAG_ZAP_OLD, label); 588 kfree(label); 589 if (IS_ERR(*prz)) { 590 int err = PTR_ERR(*prz); 591 592 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n", 593 name, sz, (unsigned long long)*paddr, err); 594 return err; 595 } 596 597 *paddr += sz; 598 (*prz)->type = pstore_name_to_type(name); 599 600 return 0; 601 } 602 603 /* Read a u32 from a dt property and make sure it's safe for an int. */ 604 static int ramoops_parse_dt_u32(struct platform_device *pdev, 605 const char *propname, 606 u32 default_value, u32 *value) 607 { 608 u32 val32 = 0; 609 int ret; 610 611 ret = of_property_read_u32(pdev->dev.of_node, propname, &val32); 612 if (ret == -EINVAL) { 613 /* field is missing, use default value. */ 614 val32 = default_value; 615 } else if (ret < 0) { 616 dev_err(&pdev->dev, "failed to parse property %s: %d\n", 617 propname, ret); 618 return ret; 619 } 620 621 /* Sanity check our results. */ 622 if (val32 > INT_MAX) { 623 dev_err(&pdev->dev, "%s %u > INT_MAX\n", propname, val32); 624 return -EOVERFLOW; 625 } 626 627 *value = val32; 628 return 0; 629 } 630 631 static int ramoops_parse_dt(struct platform_device *pdev, 632 struct ramoops_platform_data *pdata) 633 { 634 struct device_node *of_node = pdev->dev.of_node; 635 struct device_node *parent_node; 636 struct resource *res; 637 u32 value; 638 int ret; 639 640 dev_dbg(&pdev->dev, "using Device Tree\n"); 641 642 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 643 if (!res) { 644 dev_err(&pdev->dev, 645 "failed to locate DT /reserved-memory resource\n"); 646 return -EINVAL; 647 } 648 649 pdata->mem_size = resource_size(res); 650 pdata->mem_address = res->start; 651 /* 652 * Setting "unbuffered" is deprecated and will be ignored if 653 * "mem_type" is also specified. 654 */ 655 pdata->mem_type = of_property_read_bool(of_node, "unbuffered"); 656 /* 657 * Setting "no-dump-oops" is deprecated and will be ignored if 658 * "max_reason" is also specified. 659 */ 660 if (of_property_read_bool(of_node, "no-dump-oops")) 661 pdata->max_reason = KMSG_DUMP_PANIC; 662 else 663 pdata->max_reason = KMSG_DUMP_OOPS; 664 665 #define parse_u32(name, field, default_value) { \ 666 ret = ramoops_parse_dt_u32(pdev, name, default_value, \ 667 &value); \ 668 if (ret < 0) \ 669 return ret; \ 670 field = value; \ 671 } 672 673 parse_u32("mem-type", pdata->record_size, pdata->mem_type); 674 parse_u32("record-size", pdata->record_size, 0); 675 parse_u32("console-size", pdata->console_size, 0); 676 parse_u32("ftrace-size", pdata->ftrace_size, 0); 677 parse_u32("pmsg-size", pdata->pmsg_size, 0); 678 parse_u32("ecc-size", pdata->ecc_info.ecc_size, 0); 679 parse_u32("flags", pdata->flags, 0); 680 parse_u32("max-reason", pdata->max_reason, pdata->max_reason); 681 682 #undef parse_u32 683 684 /* 685 * Some old Chromebooks relied on the kernel setting the 686 * console_size and pmsg_size to the record size since that's 687 * what the downstream kernel did. These same Chromebooks had 688 * "ramoops" straight under the root node which isn't 689 * according to the current upstream bindings (though it was 690 * arguably acceptable under a prior version of the bindings). 691 * Let's make those old Chromebooks work by detecting that 692 * we're not a child of "reserved-memory" and mimicking the 693 * expected behavior. 694 */ 695 parent_node = of_get_parent(of_node); 696 if (!of_node_name_eq(parent_node, "reserved-memory") && 697 !pdata->console_size && !pdata->ftrace_size && 698 !pdata->pmsg_size && !pdata->ecc_info.ecc_size) { 699 pdata->console_size = pdata->record_size; 700 pdata->pmsg_size = pdata->record_size; 701 } 702 of_node_put(parent_node); 703 704 return 0; 705 } 706 707 static int ramoops_probe(struct platform_device *pdev) 708 { 709 struct device *dev = &pdev->dev; 710 struct ramoops_platform_data *pdata = dev->platform_data; 711 struct ramoops_platform_data pdata_local; 712 struct ramoops_context *cxt = &oops_cxt; 713 size_t dump_mem_sz; 714 phys_addr_t paddr; 715 int err = -EINVAL; 716 717 /* 718 * Only a single ramoops area allowed at a time, so fail extra 719 * probes. 720 */ 721 if (cxt->max_dump_cnt) { 722 pr_err("already initialized\n"); 723 goto fail_out; 724 } 725 726 if (dev_of_node(dev) && !pdata) { 727 pdata = &pdata_local; 728 memset(pdata, 0, sizeof(*pdata)); 729 730 err = ramoops_parse_dt(pdev, pdata); 731 if (err < 0) 732 goto fail_out; 733 } 734 735 /* Make sure we didn't get bogus platform data pointer. */ 736 if (!pdata) { 737 pr_err("NULL platform data\n"); 738 goto fail_out; 739 } 740 741 if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size && 742 !pdata->ftrace_size && !pdata->pmsg_size)) { 743 pr_err("The memory size and the record/console size must be " 744 "non-zero\n"); 745 goto fail_out; 746 } 747 748 if (pdata->record_size && !is_power_of_2(pdata->record_size)) 749 pdata->record_size = rounddown_pow_of_two(pdata->record_size); 750 if (pdata->console_size && !is_power_of_2(pdata->console_size)) 751 pdata->console_size = rounddown_pow_of_two(pdata->console_size); 752 if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size)) 753 pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size); 754 if (pdata->pmsg_size && !is_power_of_2(pdata->pmsg_size)) 755 pdata->pmsg_size = rounddown_pow_of_two(pdata->pmsg_size); 756 757 cxt->size = pdata->mem_size; 758 cxt->phys_addr = pdata->mem_address; 759 cxt->memtype = pdata->mem_type; 760 cxt->record_size = pdata->record_size; 761 cxt->console_size = pdata->console_size; 762 cxt->ftrace_size = pdata->ftrace_size; 763 cxt->pmsg_size = pdata->pmsg_size; 764 cxt->flags = pdata->flags; 765 cxt->ecc_info = pdata->ecc_info; 766 767 paddr = cxt->phys_addr; 768 769 dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size 770 - cxt->pmsg_size; 771 err = ramoops_init_przs("dmesg", dev, cxt, &cxt->dprzs, &paddr, 772 dump_mem_sz, cxt->record_size, 773 &cxt->max_dump_cnt, 0, 0); 774 if (err) 775 goto fail_out; 776 777 err = ramoops_init_prz("console", dev, cxt, &cxt->cprz, &paddr, 778 cxt->console_size, 0); 779 if (err) 780 goto fail_init_cprz; 781 782 cxt->max_ftrace_cnt = (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) 783 ? nr_cpu_ids 784 : 1; 785 err = ramoops_init_przs("ftrace", dev, cxt, &cxt->fprzs, &paddr, 786 cxt->ftrace_size, -1, 787 &cxt->max_ftrace_cnt, LINUX_VERSION_CODE, 788 (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) 789 ? PRZ_FLAG_NO_LOCK : 0); 790 if (err) 791 goto fail_init_fprz; 792 793 err = ramoops_init_prz("pmsg", dev, cxt, &cxt->mprz, &paddr, 794 cxt->pmsg_size, 0); 795 if (err) 796 goto fail_init_mprz; 797 798 cxt->pstore.data = cxt; 799 /* 800 * Prepare frontend flags based on which areas are initialized. 801 * For ramoops_init_przs() cases, the "max count" variable tells 802 * if there are regions present. For ramoops_init_prz() cases, 803 * the single region size is how to check. 804 */ 805 cxt->pstore.flags = 0; 806 if (cxt->max_dump_cnt) { 807 cxt->pstore.flags |= PSTORE_FLAGS_DMESG; 808 cxt->pstore.max_reason = pdata->max_reason; 809 } 810 if (cxt->console_size) 811 cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE; 812 if (cxt->max_ftrace_cnt) 813 cxt->pstore.flags |= PSTORE_FLAGS_FTRACE; 814 if (cxt->pmsg_size) 815 cxt->pstore.flags |= PSTORE_FLAGS_PMSG; 816 817 /* 818 * Since bufsize is only used for dmesg crash dumps, it 819 * must match the size of the dprz record (after PRZ header 820 * and ECC bytes have been accounted for). 821 */ 822 if (cxt->pstore.flags & PSTORE_FLAGS_DMESG) { 823 cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size; 824 cxt->pstore.buf = kzalloc(cxt->pstore.bufsize, GFP_KERNEL); 825 if (!cxt->pstore.buf) { 826 pr_err("cannot allocate pstore crash dump buffer\n"); 827 err = -ENOMEM; 828 goto fail_clear; 829 } 830 } 831 832 err = pstore_register(&cxt->pstore); 833 if (err) { 834 pr_err("registering with pstore failed\n"); 835 goto fail_buf; 836 } 837 838 /* 839 * Update the module parameter variables as well so they are visible 840 * through /sys/module/ramoops/parameters/ 841 */ 842 mem_size = pdata->mem_size; 843 mem_address = pdata->mem_address; 844 record_size = pdata->record_size; 845 ramoops_max_reason = pdata->max_reason; 846 ramoops_console_size = pdata->console_size; 847 ramoops_pmsg_size = pdata->pmsg_size; 848 ramoops_ftrace_size = pdata->ftrace_size; 849 850 pr_info("using 0x%lx@0x%llx, ecc: %d\n", 851 cxt->size, (unsigned long long)cxt->phys_addr, 852 cxt->ecc_info.ecc_size); 853 854 return 0; 855 856 fail_buf: 857 kfree(cxt->pstore.buf); 858 fail_clear: 859 cxt->pstore.bufsize = 0; 860 persistent_ram_free(cxt->mprz); 861 fail_init_mprz: 862 fail_init_fprz: 863 persistent_ram_free(cxt->cprz); 864 fail_init_cprz: 865 ramoops_free_przs(cxt); 866 fail_out: 867 return err; 868 } 869 870 static int ramoops_remove(struct platform_device *pdev) 871 { 872 struct ramoops_context *cxt = &oops_cxt; 873 874 pstore_unregister(&cxt->pstore); 875 876 kfree(cxt->pstore.buf); 877 cxt->pstore.bufsize = 0; 878 879 persistent_ram_free(cxt->mprz); 880 persistent_ram_free(cxt->cprz); 881 ramoops_free_przs(cxt); 882 883 return 0; 884 } 885 886 static const struct of_device_id dt_match[] = { 887 { .compatible = "ramoops" }, 888 {} 889 }; 890 891 static struct platform_driver ramoops_driver = { 892 .probe = ramoops_probe, 893 .remove = ramoops_remove, 894 .driver = { 895 .name = "ramoops", 896 .of_match_table = dt_match, 897 }, 898 }; 899 900 static inline void ramoops_unregister_dummy(void) 901 { 902 platform_device_unregister(dummy); 903 dummy = NULL; 904 } 905 906 static void __init ramoops_register_dummy(void) 907 { 908 struct ramoops_platform_data pdata; 909 910 /* 911 * Prepare a dummy platform data structure to carry the module 912 * parameters. If mem_size isn't set, then there are no module 913 * parameters, and we can skip this. 914 */ 915 if (!mem_size) 916 return; 917 918 pr_info("using module parameters\n"); 919 920 memset(&pdata, 0, sizeof(pdata)); 921 pdata.mem_size = mem_size; 922 pdata.mem_address = mem_address; 923 pdata.mem_type = mem_type; 924 pdata.record_size = record_size; 925 pdata.console_size = ramoops_console_size; 926 pdata.ftrace_size = ramoops_ftrace_size; 927 pdata.pmsg_size = ramoops_pmsg_size; 928 /* If "max_reason" is set, its value has priority over "dump_oops". */ 929 if (ramoops_max_reason >= 0) 930 pdata.max_reason = ramoops_max_reason; 931 /* Otherwise, if "dump_oops" is set, parse it into "max_reason". */ 932 else if (ramoops_dump_oops != -1) 933 pdata.max_reason = ramoops_dump_oops ? KMSG_DUMP_OOPS 934 : KMSG_DUMP_PANIC; 935 /* And if neither are explicitly set, use the default. */ 936 else 937 pdata.max_reason = KMSG_DUMP_OOPS; 938 pdata.flags = RAMOOPS_FLAG_FTRACE_PER_CPU; 939 940 /* 941 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC 942 * (using 1 byte for ECC isn't much of use anyway). 943 */ 944 pdata.ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc; 945 946 dummy = platform_device_register_data(NULL, "ramoops", -1, 947 &pdata, sizeof(pdata)); 948 if (IS_ERR(dummy)) { 949 pr_info("could not create platform device: %ld\n", 950 PTR_ERR(dummy)); 951 dummy = NULL; 952 } 953 } 954 955 static int __init ramoops_init(void) 956 { 957 int ret; 958 959 ramoops_register_dummy(); 960 ret = platform_driver_register(&ramoops_driver); 961 if (ret != 0) 962 ramoops_unregister_dummy(); 963 964 return ret; 965 } 966 postcore_initcall(ramoops_init); 967 968 static void __exit ramoops_exit(void) 969 { 970 platform_driver_unregister(&ramoops_driver); 971 ramoops_unregister_dummy(); 972 } 973 module_exit(ramoops_exit); 974 975 MODULE_LICENSE("GPL"); 976 MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>"); 977 MODULE_DESCRIPTION("RAM Oops/Panic logger/driver"); 978