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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * RAM Oops/Panic logger4 *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 ": " fmt10 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/of.h>22#include <linux/of_address.h>23#include <linux/mm.h>24 25#include "internal.h"26#include "ram_internal.h"27 28#define RAMOOPS_KERNMSG_HDR "===="29#define MIN_MEM_SIZE 4096UL30 31static ulong record_size = MIN_MEM_SIZE;32module_param(record_size, ulong, 0400);33MODULE_PARM_DESC(record_size,34 "size of each dump done on oops/panic");35 36static ulong ramoops_console_size = MIN_MEM_SIZE;37module_param_named(console_size, ramoops_console_size, ulong, 0400);38MODULE_PARM_DESC(console_size, "size of kernel console log");39 40static ulong ramoops_ftrace_size = MIN_MEM_SIZE;41module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400);42MODULE_PARM_DESC(ftrace_size, "size of ftrace log");43 44static ulong ramoops_pmsg_size = MIN_MEM_SIZE;45module_param_named(pmsg_size, ramoops_pmsg_size, ulong, 0400);46MODULE_PARM_DESC(pmsg_size, "size of user space message log");47 48static unsigned long long mem_address;49module_param_hw(mem_address, ullong, other, 0400);50MODULE_PARM_DESC(mem_address,51 "start of reserved RAM used to store oops/panic logs");52 53static char *mem_name;54module_param_named(mem_name, mem_name, charp, 0400);55MODULE_PARM_DESC(mem_name, "name of kernel param that holds addr");56 57static ulong mem_size;58module_param(mem_size, ulong, 0400);59MODULE_PARM_DESC(mem_size,60 "size of reserved RAM used to store oops/panic logs");61 62static unsigned int mem_type;63module_param(mem_type, uint, 0400);64MODULE_PARM_DESC(mem_type,65 "memory type: 0=write-combined (default), 1=unbuffered, 2=cached");66 67static int ramoops_max_reason = -1;68module_param_named(max_reason, ramoops_max_reason, int, 0400);69MODULE_PARM_DESC(max_reason,70 "maximum reason for kmsg dump (default 2: Oops and Panic) ");71 72static int ramoops_ecc;73module_param_named(ecc, ramoops_ecc, int, 0400);74MODULE_PARM_DESC(ramoops_ecc,75 "if non-zero, the option enables ECC support and specifies "76 "ECC buffer size in bytes (1 is a special value, means 16 "77 "bytes ECC)");78 79static int ramoops_dump_oops = -1;80module_param_named(dump_oops, ramoops_dump_oops, int, 0400);81MODULE_PARM_DESC(dump_oops,82 "(deprecated: use max_reason instead) set to 1 to dump oopses & panics, 0 to only dump panics");83 84struct ramoops_context {85 struct persistent_ram_zone **dprzs; /* Oops dump zones */86 struct persistent_ram_zone *cprz; /* Console zone */87 struct persistent_ram_zone **fprzs; /* Ftrace zones */88 struct persistent_ram_zone *mprz; /* PMSG zone */89 phys_addr_t phys_addr;90 unsigned long size;91 unsigned int memtype;92 size_t record_size;93 size_t console_size;94 size_t ftrace_size;95 size_t pmsg_size;96 u32 flags;97 struct persistent_ram_ecc_info ecc_info;98 unsigned int max_dump_cnt;99 unsigned int dump_write_cnt;100 /* _read_cnt need clear on ramoops_pstore_open */101 unsigned int dump_read_cnt;102 unsigned int console_read_cnt;103 unsigned int max_ftrace_cnt;104 unsigned int ftrace_read_cnt;105 unsigned int pmsg_read_cnt;106 struct pstore_info pstore;107};108 109static struct platform_device *dummy;110 111static int ramoops_pstore_open(struct pstore_info *psi)112{113 struct ramoops_context *cxt = psi->data;114 115 cxt->dump_read_cnt = 0;116 cxt->console_read_cnt = 0;117 cxt->ftrace_read_cnt = 0;118 cxt->pmsg_read_cnt = 0;119 return 0;120}121 122static struct persistent_ram_zone *123ramoops_get_next_prz(struct persistent_ram_zone *przs[], int id,124 struct pstore_record *record)125{126 struct persistent_ram_zone *prz;127 128 /* Give up if we never existed or have hit the end. */129 if (!przs)130 return NULL;131 132 prz = przs[id];133 if (!prz)134 return NULL;135 136 /* Update old/shadowed buffer. */137 if (prz->type == PSTORE_TYPE_DMESG)138 persistent_ram_save_old(prz);139 140 if (!persistent_ram_old_size(prz))141 return NULL;142 143 record->type = prz->type;144 record->id = id;145 146 return prz;147}148 149static int ramoops_read_kmsg_hdr(char *buffer, struct timespec64 *time,150 bool *compressed)151{152 char data_type;153 int header_length = 0;154 155 if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu-%c\n%n",156 (time64_t *)&time->tv_sec, &time->tv_nsec, &data_type,157 &header_length) == 3) {158 time->tv_nsec *= 1000;159 if (data_type == 'C')160 *compressed = true;161 else162 *compressed = false;163 } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lld.%lu\n%n",164 (time64_t *)&time->tv_sec, &time->tv_nsec,165 &header_length) == 2) {166 time->tv_nsec *= 1000;167 *compressed = false;168 } else {169 time->tv_sec = 0;170 time->tv_nsec = 0;171 *compressed = false;172 }173 return header_length;174}175 176static bool prz_ok(struct persistent_ram_zone *prz)177{178 return !!prz && !!(persistent_ram_old_size(prz) +179 persistent_ram_ecc_string(prz, NULL, 0));180}181 182static ssize_t ramoops_pstore_read(struct pstore_record *record)183{184 ssize_t size = 0;185 struct ramoops_context *cxt = record->psi->data;186 struct persistent_ram_zone *prz = NULL;187 int header_length = 0;188 bool free_prz = false;189 190 /*191 * Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but192 * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have193 * valid time stamps, so it is initialized to zero.194 */195 record->time.tv_sec = 0;196 record->time.tv_nsec = 0;197 record->compressed = false;198 199 /* Find the next valid persistent_ram_zone for DMESG */200 while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) {201 prz = ramoops_get_next_prz(cxt->dprzs, cxt->dump_read_cnt++,202 record);203 if (!prz_ok(prz))204 continue;205 header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz),206 &record->time,207 &record->compressed);208 /* Clear and skip this DMESG record if it has no valid header */209 if (!header_length) {210 persistent_ram_free_old(prz);211 persistent_ram_zap(prz);212 prz = NULL;213 }214 }215 216 if (!prz_ok(prz) && !cxt->console_read_cnt++)217 prz = ramoops_get_next_prz(&cxt->cprz, 0 /* single */, record);218 219 if (!prz_ok(prz) && !cxt->pmsg_read_cnt++)220 prz = ramoops_get_next_prz(&cxt->mprz, 0 /* single */, record);221 222 /* ftrace is last since it may want to dynamically allocate memory. */223 if (!prz_ok(prz)) {224 if (!(cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU) &&225 !cxt->ftrace_read_cnt++) {226 prz = ramoops_get_next_prz(cxt->fprzs, 0 /* single */,227 record);228 } else {229 /*230 * Build a new dummy record which combines all the231 * per-cpu records including metadata and ecc info.232 */233 struct persistent_ram_zone *tmp_prz, *prz_next;234 235 tmp_prz = kzalloc(sizeof(struct persistent_ram_zone),236 GFP_KERNEL);237 if (!tmp_prz)238 return -ENOMEM;239 prz = tmp_prz;240 free_prz = true;241 242 while (cxt->ftrace_read_cnt < cxt->max_ftrace_cnt) {243 prz_next = ramoops_get_next_prz(cxt->fprzs,244 cxt->ftrace_read_cnt++, record);245 246 if (!prz_ok(prz_next))247 continue;248 249 tmp_prz->ecc_info = prz_next->ecc_info;250 tmp_prz->corrected_bytes +=251 prz_next->corrected_bytes;252 tmp_prz->bad_blocks += prz_next->bad_blocks;253 254 size = pstore_ftrace_combine_log(255 &tmp_prz->old_log,256 &tmp_prz->old_log_size,257 prz_next->old_log,258 prz_next->old_log_size);259 if (size)260 goto out;261 }262 record->id = 0;263 }264 }265 266 if (!prz_ok(prz)) {267 size = 0;268 goto out;269 }270 271 size = persistent_ram_old_size(prz) - header_length;272 273 /* ECC correction notice */274 record->ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);275 276 record->buf = kvzalloc(size + record->ecc_notice_size + 1, GFP_KERNEL);277 if (record->buf == NULL) {278 size = -ENOMEM;279 goto out;280 }281 282 memcpy(record->buf, (char *)persistent_ram_old(prz) + header_length,283 size);284 285 persistent_ram_ecc_string(prz, record->buf + size,286 record->ecc_notice_size + 1);287 288out:289 if (free_prz) {290 kvfree(prz->old_log);291 kfree(prz);292 }293 294 return size;295}296 297static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,298 struct pstore_record *record)299{300 char hdr[36]; /* "===="(4), %lld(20), "."(1), %06lu(6), "-%c\n"(3) */301 size_t len;302 303 len = scnprintf(hdr, sizeof(hdr),304 RAMOOPS_KERNMSG_HDR "%lld.%06lu-%c\n",305 (time64_t)record->time.tv_sec,306 record->time.tv_nsec / 1000,307 record->compressed ? 'C' : 'D');308 persistent_ram_write(prz, hdr, len);309 310 return len;311}312 313static int notrace ramoops_pstore_write(struct pstore_record *record)314{315 struct ramoops_context *cxt = record->psi->data;316 struct persistent_ram_zone *prz;317 size_t size, hlen;318 319 if (record->type == PSTORE_TYPE_CONSOLE) {320 if (!cxt->cprz)321 return -ENOMEM;322 persistent_ram_write(cxt->cprz, record->buf, record->size);323 return 0;324 } else if (record->type == PSTORE_TYPE_FTRACE) {325 int zonenum;326 327 if (!cxt->fprzs)328 return -ENOMEM;329 /*330 * Choose zone by if we're using per-cpu buffers.331 */332 if (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)333 zonenum = smp_processor_id();334 else335 zonenum = 0;336 337 persistent_ram_write(cxt->fprzs[zonenum], record->buf,338 record->size);339 return 0;340 } else if (record->type == PSTORE_TYPE_PMSG) {341 pr_warn_ratelimited("PMSG shouldn't call %s\n", __func__);342 return -EINVAL;343 }344 345 if (record->type != PSTORE_TYPE_DMESG)346 return -EINVAL;347 348 /*349 * We could filter on record->reason here if we wanted to (which350 * would duplicate what happened before the "max_reason" setting351 * was added), but that would defeat the purpose of a system352 * changing printk.always_kmsg_dump, so instead log everything that353 * the kmsg dumper sends us, since it should be doing the filtering354 * based on the combination of printk.always_kmsg_dump and our355 * requested "max_reason".356 */357 358 /*359 * Explicitly only take the first part of any new crash.360 * If our buffer is larger than kmsg_bytes, this can never happen,361 * and if our buffer is smaller than kmsg_bytes, we don't want the362 * report split across multiple records.363 */364 if (record->part != 1)365 return -ENOSPC;366 367 if (!cxt->dprzs)368 return -ENOSPC;369 370 prz = cxt->dprzs[cxt->dump_write_cnt];371 372 /*373 * Since this is a new crash dump, we need to reset the buffer in374 * case it still has an old dump present. Without this, the new dump375 * will get appended, which would seriously confuse anything trying376 * to check dump file contents. Specifically, ramoops_read_kmsg_hdr()377 * expects to find a dump header in the beginning of buffer data, so378 * we must to reset the buffer values, in order to ensure that the379 * header will be written to the beginning of the buffer.380 */381 persistent_ram_zap(prz);382 383 /* Build header and append record contents. */384 hlen = ramoops_write_kmsg_hdr(prz, record);385 if (!hlen)386 return -ENOMEM;387 388 size = record->size;389 if (size + hlen > prz->buffer_size)390 size = prz->buffer_size - hlen;391 persistent_ram_write(prz, record->buf, size);392 393 cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;394 395 return 0;396}397 398static int notrace ramoops_pstore_write_user(struct pstore_record *record,399 const char __user *buf)400{401 if (record->type == PSTORE_TYPE_PMSG) {402 struct ramoops_context *cxt = record->psi->data;403 404 if (!cxt->mprz)405 return -ENOMEM;406 return persistent_ram_write_user(cxt->mprz, buf, record->size);407 }408 409 return -EINVAL;410}411 412static int ramoops_pstore_erase(struct pstore_record *record)413{414 struct ramoops_context *cxt = record->psi->data;415 struct persistent_ram_zone *prz;416 417 switch (record->type) {418 case PSTORE_TYPE_DMESG:419 if (record->id >= cxt->max_dump_cnt)420 return -EINVAL;421 prz = cxt->dprzs[record->id];422 break;423 case PSTORE_TYPE_CONSOLE:424 prz = cxt->cprz;425 break;426 case PSTORE_TYPE_FTRACE:427 if (record->id >= cxt->max_ftrace_cnt)428 return -EINVAL;429 prz = cxt->fprzs[record->id];430 break;431 case PSTORE_TYPE_PMSG:432 prz = cxt->mprz;433 break;434 default:435 return -EINVAL;436 }437 438 persistent_ram_free_old(prz);439 persistent_ram_zap(prz);440 441 return 0;442}443 444static struct ramoops_context oops_cxt = {445 .pstore = {446 .owner = THIS_MODULE,447 .name = "ramoops",448 .open = ramoops_pstore_open,449 .read = ramoops_pstore_read,450 .write = ramoops_pstore_write,451 .write_user = ramoops_pstore_write_user,452 .erase = ramoops_pstore_erase,453 },454};455 456static void ramoops_free_przs(struct ramoops_context *cxt)457{458 int i;459 460 /* Free pmsg PRZ */461 persistent_ram_free(&cxt->mprz);462 463 /* Free console PRZ */464 persistent_ram_free(&cxt->cprz);465 466 /* Free dump PRZs */467 if (cxt->dprzs) {468 for (i = 0; i < cxt->max_dump_cnt; i++)469 persistent_ram_free(&cxt->dprzs[i]);470 471 kfree(cxt->dprzs);472 cxt->dprzs = NULL;473 cxt->max_dump_cnt = 0;474 }475 476 /* Free ftrace PRZs */477 if (cxt->fprzs) {478 for (i = 0; i < cxt->max_ftrace_cnt; i++)479 persistent_ram_free(&cxt->fprzs[i]);480 kfree(cxt->fprzs);481 cxt->fprzs = NULL;482 cxt->max_ftrace_cnt = 0;483 }484}485 486static int ramoops_init_przs(const char *name,487 struct device *dev, struct ramoops_context *cxt,488 struct persistent_ram_zone ***przs,489 phys_addr_t *paddr, size_t mem_sz,490 ssize_t record_size,491 unsigned int *cnt, u32 sig, u32 flags)492{493 int err = -ENOMEM;494 int i;495 size_t zone_sz;496 struct persistent_ram_zone **prz_ar;497 498 /* Allocate nothing for 0 mem_sz or 0 record_size. */499 if (mem_sz == 0 || record_size == 0) {500 *cnt = 0;501 return 0;502 }503 504 /*505 * If we have a negative record size, calculate it based on506 * mem_sz / *cnt. If we have a positive record size, calculate507 * cnt from mem_sz / record_size.508 */509 if (record_size < 0) {510 if (*cnt == 0)511 return 0;512 record_size = mem_sz / *cnt;513 if (record_size == 0) {514 dev_err(dev, "%s record size == 0 (%zu / %u)\n",515 name, mem_sz, *cnt);516 goto fail;517 }518 } else {519 *cnt = mem_sz / record_size;520 if (*cnt == 0) {521 dev_err(dev, "%s record count == 0 (%zu / %zu)\n",522 name, mem_sz, record_size);523 goto fail;524 }525 }526 527 if (*paddr + mem_sz - cxt->phys_addr > cxt->size) {528 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",529 name,530 mem_sz, (unsigned long long)*paddr,531 cxt->size, (unsigned long long)cxt->phys_addr);532 goto fail;533 }534 535 zone_sz = mem_sz / *cnt;536 zone_sz = ALIGN_DOWN(zone_sz, 2);537 if (!zone_sz) {538 dev_err(dev, "%s zone size == 0\n", name);539 goto fail;540 }541 542 prz_ar = kcalloc(*cnt, sizeof(**przs), GFP_KERNEL);543 if (!prz_ar)544 goto fail;545 546 for (i = 0; i < *cnt; i++) {547 char *label;548 549 if (*cnt == 1)550 label = kasprintf(GFP_KERNEL, "ramoops:%s", name);551 else552 label = kasprintf(GFP_KERNEL, "ramoops:%s(%d/%d)",553 name, i, *cnt - 1);554 prz_ar[i] = persistent_ram_new(*paddr, zone_sz, sig,555 &cxt->ecc_info,556 cxt->memtype, flags, label);557 kfree(label);558 if (IS_ERR(prz_ar[i])) {559 err = PTR_ERR(prz_ar[i]);560 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",561 name, record_size,562 (unsigned long long)*paddr, err);563 564 while (i > 0) {565 i--;566 persistent_ram_free(&prz_ar[i]);567 }568 kfree(prz_ar);569 prz_ar = NULL;570 goto fail;571 }572 *paddr += zone_sz;573 prz_ar[i]->type = pstore_name_to_type(name);574 }575 576 *przs = prz_ar;577 return 0;578 579fail:580 *cnt = 0;581 return err;582}583 584static int ramoops_init_prz(const char *name,585 struct device *dev, struct ramoops_context *cxt,586 struct persistent_ram_zone **prz,587 phys_addr_t *paddr, size_t sz, u32 sig)588{589 char *label;590 591 if (!sz)592 return 0;593 594 if (*paddr + sz - cxt->phys_addr > cxt->size) {595 dev_err(dev, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",596 name, sz, (unsigned long long)*paddr,597 cxt->size, (unsigned long long)cxt->phys_addr);598 return -ENOMEM;599 }600 601 label = kasprintf(GFP_KERNEL, "ramoops:%s", name);602 *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info,603 cxt->memtype, PRZ_FLAG_ZAP_OLD, label);604 kfree(label);605 if (IS_ERR(*prz)) {606 int err = PTR_ERR(*prz);607 608 dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",609 name, sz, (unsigned long long)*paddr, err);610 return err;611 }612 613 *paddr += sz;614 (*prz)->type = pstore_name_to_type(name);615 616 return 0;617}618 619/* Read a u32 from a dt property and make sure it's safe for an int. */620static int ramoops_parse_dt_u32(struct platform_device *pdev,621 const char *propname,622 u32 default_value, u32 *value)623{624 u32 val32 = 0;625 int ret;626 627 ret = of_property_read_u32(pdev->dev.of_node, propname, &val32);628 if (ret == -EINVAL) {629 /* field is missing, use default value. */630 val32 = default_value;631 } else if (ret < 0) {632 dev_err(&pdev->dev, "failed to parse property %s: %d\n",633 propname, ret);634 return ret;635 }636 637 /* Sanity check our results. */638 if (val32 > INT_MAX) {639 dev_err(&pdev->dev, "%s %u > INT_MAX\n", propname, val32);640 return -EOVERFLOW;641 }642 643 *value = val32;644 return 0;645}646 647static int ramoops_parse_dt(struct platform_device *pdev,648 struct ramoops_platform_data *pdata)649{650 struct device_node *of_node = pdev->dev.of_node;651 struct device_node *parent_node;652 struct resource *res;653 u32 value;654 int ret;655 656 dev_dbg(&pdev->dev, "using Device Tree\n");657 658 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);659 if (!res) {660 dev_err(&pdev->dev,661 "failed to locate DT /reserved-memory resource\n");662 return -EINVAL;663 }664 665 pdata->mem_size = resource_size(res);666 pdata->mem_address = res->start;667 /*668 * Setting "unbuffered" is deprecated and will be ignored if669 * "mem_type" is also specified.670 */671 pdata->mem_type = of_property_read_bool(of_node, "unbuffered");672 /*673 * Setting "no-dump-oops" is deprecated and will be ignored if674 * "max_reason" is also specified.675 */676 if (of_property_read_bool(of_node, "no-dump-oops"))677 pdata->max_reason = KMSG_DUMP_PANIC;678 else679 pdata->max_reason = KMSG_DUMP_OOPS;680 681#define parse_u32(name, field, default_value) { \682 ret = ramoops_parse_dt_u32(pdev, name, default_value, \683 &value); \684 if (ret < 0) \685 return ret; \686 field = value; \687 }688 689 parse_u32("mem-type", pdata->mem_type, pdata->mem_type);690 parse_u32("record-size", pdata->record_size, 0);691 parse_u32("console-size", pdata->console_size, 0);692 parse_u32("ftrace-size", pdata->ftrace_size, 0);693 parse_u32("pmsg-size", pdata->pmsg_size, 0);694 parse_u32("ecc-size", pdata->ecc_info.ecc_size, 0);695 parse_u32("flags", pdata->flags, 0);696 parse_u32("max-reason", pdata->max_reason, pdata->max_reason);697 698#undef parse_u32699 700 /*701 * Some old Chromebooks relied on the kernel setting the702 * console_size and pmsg_size to the record size since that's703 * what the downstream kernel did. These same Chromebooks had704 * "ramoops" straight under the root node which isn't705 * according to the current upstream bindings (though it was706 * arguably acceptable under a prior version of the bindings).707 * Let's make those old Chromebooks work by detecting that708 * we're not a child of "reserved-memory" and mimicking the709 * expected behavior.710 */711 parent_node = of_get_parent(of_node);712 if (!of_node_name_eq(parent_node, "reserved-memory") &&713 !pdata->console_size && !pdata->ftrace_size &&714 !pdata->pmsg_size && !pdata->ecc_info.ecc_size) {715 pdata->console_size = pdata->record_size;716 pdata->pmsg_size = pdata->record_size;717 }718 of_node_put(parent_node);719 720 return 0;721}722 723static int ramoops_probe(struct platform_device *pdev)724{725 struct device *dev = &pdev->dev;726 struct ramoops_platform_data *pdata = dev->platform_data;727 struct ramoops_platform_data pdata_local;728 struct ramoops_context *cxt = &oops_cxt;729 size_t dump_mem_sz;730 phys_addr_t paddr;731 int err = -EINVAL;732 733 /*734 * Only a single ramoops area allowed at a time, so fail extra735 * probes.736 */737 if (cxt->max_dump_cnt) {738 pr_err("already initialized\n");739 goto fail_out;740 }741 742 if (dev_of_node(dev) && !pdata) {743 pdata = &pdata_local;744 memset(pdata, 0, sizeof(*pdata));745 746 err = ramoops_parse_dt(pdev, pdata);747 if (err < 0)748 goto fail_out;749 }750 751 /* Make sure we didn't get bogus platform data pointer. */752 if (!pdata) {753 pr_err("NULL platform data\n");754 err = -EINVAL;755 goto fail_out;756 }757 758 if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&759 !pdata->ftrace_size && !pdata->pmsg_size)) {760 pr_err("The memory size and the record/console size must be "761 "non-zero\n");762 err = -EINVAL;763 goto fail_out;764 }765 766 if (pdata->record_size && !is_power_of_2(pdata->record_size))767 pdata->record_size = rounddown_pow_of_two(pdata->record_size);768 if (pdata->console_size && !is_power_of_2(pdata->console_size))769 pdata->console_size = rounddown_pow_of_two(pdata->console_size);770 if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))771 pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);772 if (pdata->pmsg_size && !is_power_of_2(pdata->pmsg_size))773 pdata->pmsg_size = rounddown_pow_of_two(pdata->pmsg_size);774 775 cxt->size = pdata->mem_size;776 cxt->phys_addr = pdata->mem_address;777 cxt->memtype = pdata->mem_type;778 cxt->record_size = pdata->record_size;779 cxt->console_size = pdata->console_size;780 cxt->ftrace_size = pdata->ftrace_size;781 cxt->pmsg_size = pdata->pmsg_size;782 cxt->flags = pdata->flags;783 cxt->ecc_info = pdata->ecc_info;784 785 paddr = cxt->phys_addr;786 787 dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size788 - cxt->pmsg_size;789 err = ramoops_init_przs("dmesg", dev, cxt, &cxt->dprzs, &paddr,790 dump_mem_sz, cxt->record_size,791 &cxt->max_dump_cnt, 0, 0);792 if (err)793 goto fail_init;794 795 err = ramoops_init_prz("console", dev, cxt, &cxt->cprz, &paddr,796 cxt->console_size, 0);797 if (err)798 goto fail_init;799 800 err = ramoops_init_prz("pmsg", dev, cxt, &cxt->mprz, &paddr,801 cxt->pmsg_size, 0);802 if (err)803 goto fail_init;804 805 cxt->max_ftrace_cnt = (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)806 ? nr_cpu_ids807 : 1;808 err = ramoops_init_przs("ftrace", dev, cxt, &cxt->fprzs, &paddr,809 cxt->ftrace_size, -1,810 &cxt->max_ftrace_cnt, LINUX_VERSION_CODE,811 (cxt->flags & RAMOOPS_FLAG_FTRACE_PER_CPU)812 ? PRZ_FLAG_NO_LOCK : 0);813 if (err)814 goto fail_init;815 816 cxt->pstore.data = cxt;817 /*818 * Prepare frontend flags based on which areas are initialized.819 * For ramoops_init_przs() cases, the "max count" variable tells820 * if there are regions present. For ramoops_init_prz() cases,821 * the single region size is how to check.822 */823 cxt->pstore.flags = 0;824 if (cxt->max_dump_cnt) {825 cxt->pstore.flags |= PSTORE_FLAGS_DMESG;826 cxt->pstore.max_reason = pdata->max_reason;827 }828 if (cxt->console_size)829 cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE;830 if (cxt->max_ftrace_cnt)831 cxt->pstore.flags |= PSTORE_FLAGS_FTRACE;832 if (cxt->pmsg_size)833 cxt->pstore.flags |= PSTORE_FLAGS_PMSG;834 835 /*836 * Since bufsize is only used for dmesg crash dumps, it837 * must match the size of the dprz record (after PRZ header838 * and ECC bytes have been accounted for).839 */840 if (cxt->pstore.flags & PSTORE_FLAGS_DMESG) {841 cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size;842 cxt->pstore.buf = kvzalloc(cxt->pstore.bufsize, GFP_KERNEL);843 if (!cxt->pstore.buf) {844 pr_err("cannot allocate pstore crash dump buffer\n");845 err = -ENOMEM;846 goto fail_clear;847 }848 }849 850 err = pstore_register(&cxt->pstore);851 if (err) {852 pr_err("registering with pstore failed\n");853 goto fail_buf;854 }855 856 /*857 * Update the module parameter variables as well so they are visible858 * through /sys/module/ramoops/parameters/859 */860 mem_size = pdata->mem_size;861 mem_address = pdata->mem_address;862 record_size = pdata->record_size;863 ramoops_max_reason = pdata->max_reason;864 ramoops_console_size = pdata->console_size;865 ramoops_pmsg_size = pdata->pmsg_size;866 ramoops_ftrace_size = pdata->ftrace_size;867 868 pr_info("using 0x%lx@0x%llx, ecc: %d\n",869 cxt->size, (unsigned long long)cxt->phys_addr,870 cxt->ecc_info.ecc_size);871 872 return 0;873 874fail_buf:875 kvfree(cxt->pstore.buf);876fail_clear:877 cxt->pstore.bufsize = 0;878fail_init:879 ramoops_free_przs(cxt);880fail_out:881 return err;882}883 884static void ramoops_remove(struct platform_device *pdev)885{886 struct ramoops_context *cxt = &oops_cxt;887 888 pstore_unregister(&cxt->pstore);889 890 kvfree(cxt->pstore.buf);891 cxt->pstore.bufsize = 0;892 893 ramoops_free_przs(cxt);894}895 896static const struct of_device_id dt_match[] = {897 { .compatible = "ramoops" },898 {}899};900MODULE_DEVICE_TABLE(of, dt_match);901 902static struct platform_driver ramoops_driver = {903 .probe = ramoops_probe,904 .remove_new = ramoops_remove,905 .driver = {906 .name = "ramoops",907 .of_match_table = dt_match,908 },909};910 911static inline void ramoops_unregister_dummy(void)912{913 platform_device_unregister(dummy);914 dummy = NULL;915}916 917static void __init ramoops_register_dummy(void)918{919 struct ramoops_platform_data pdata;920 921 if (mem_name) {922 phys_addr_t start;923 phys_addr_t size;924 925 if (reserve_mem_find_by_name(mem_name, &start, &size)) {926 mem_address = start;927 mem_size = size;928 }929 }930 931 /*932 * Prepare a dummy platform data structure to carry the module933 * parameters. If mem_size isn't set, then there are no module934 * parameters, and we can skip this.935 */936 if (!mem_size)937 return;938 939 pr_info("using module parameters\n");940 941 memset(&pdata, 0, sizeof(pdata));942 pdata.mem_size = mem_size;943 pdata.mem_address = mem_address;944 pdata.mem_type = mem_type;945 pdata.record_size = record_size;946 pdata.console_size = ramoops_console_size;947 pdata.ftrace_size = ramoops_ftrace_size;948 pdata.pmsg_size = ramoops_pmsg_size;949 /* If "max_reason" is set, its value has priority over "dump_oops". */950 if (ramoops_max_reason >= 0)951 pdata.max_reason = ramoops_max_reason;952 /* Otherwise, if "dump_oops" is set, parse it into "max_reason". */953 else if (ramoops_dump_oops != -1)954 pdata.max_reason = ramoops_dump_oops ? KMSG_DUMP_OOPS955 : KMSG_DUMP_PANIC;956 /* And if neither are explicitly set, use the default. */957 else958 pdata.max_reason = KMSG_DUMP_OOPS;959 pdata.flags = RAMOOPS_FLAG_FTRACE_PER_CPU;960 961 /*962 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC963 * (using 1 byte for ECC isn't much of use anyway).964 */965 pdata.ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc;966 967 dummy = platform_device_register_data(NULL, "ramoops", -1,968 &pdata, sizeof(pdata));969 if (IS_ERR(dummy)) {970 pr_info("could not create platform device: %ld\n",971 PTR_ERR(dummy));972 dummy = NULL;973 }974}975 976static int __init ramoops_init(void)977{978 int ret;979 980 ramoops_register_dummy();981 ret = platform_driver_register(&ramoops_driver);982 if (ret != 0)983 ramoops_unregister_dummy();984 985 return ret;986}987postcore_initcall(ramoops_init);988 989static void __exit ramoops_exit(void)990{991 platform_driver_unregister(&ramoops_driver);992 ramoops_unregister_dummy();993}994module_exit(ramoops_exit);995 996MODULE_LICENSE("GPL");997MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");998MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");999