fs/pstore/ram.c

   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/time.h>
  31 #include <linux/io.h>
  32 #include <linux/ioport.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/slab.h>
  35 #include <linux/compiler.h>
  36 #include <linux/pstore_ram.h>
  37 #include <linux/of.h>
  38 #include <linux/of_address.h>
  39
  40 #define RAMOOPS_KERNMSG_HDR "===="
  41 #define MIN_MEM_SIZE 4096UL
  42
  43 static ulong record_size = MIN_MEM_SIZE;
  44 module_param(record_size, ulong, 0400);
  45 MODULE_PARM_DESC(record_size,
  46                 "size of each dump done on oops/panic");
  47
  48 static ulong ramoops_console_size = MIN_MEM_SIZE;
  49 module_param_named(console_size, ramoops_console_size, ulong, 0400);
  50 MODULE_PARM_DESC(console_size, "size of kernel console log");
  51
  52 static ulong ramoops_ftrace_size = MIN_MEM_SIZE;
  53 module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400);
  54 MODULE_PARM_DESC(ftrace_size, "size of ftrace log");
  55
  56 static ulong ramoops_pmsg_size = MIN_MEM_SIZE;
  57 module_param_named(pmsg_size, ramoops_pmsg_size, ulong, 0400);
  58 MODULE_PARM_DESC(pmsg_size, "size of user space message log");
  59
  60 static ulong mem_address;
  61 module_param(mem_address, ulong, 0400);
  62 MODULE_PARM_DESC(mem_address,
  63                 "start of reserved RAM used to store oops/panic logs");
  64
  65 static ulong mem_size;
  66 module_param(mem_size, ulong, 0400);
  67 MODULE_PARM_DESC(mem_size,
  68                 "size of reserved RAM used to store oops/panic logs");
  69
  70 static unsigned int mem_type;
  71 module_param(mem_type, uint, 0600);
  72 MODULE_PARM_DESC(mem_type,
  73                 "set to 1 to try to use unbuffered memory (default 0)");
  74
  75 static int dump_oops = 1;
  76 module_param(dump_oops, int, 0600);
  77 MODULE_PARM_DESC(dump_oops,
  78                 "set to 1 to dump oopses, 0 to only dump panics (default 1)");
  79
  80 static int ramoops_ecc;
  81 module_param_named(ecc, ramoops_ecc, int, 0600);
  82 MODULE_PARM_DESC(ramoops_ecc,
  83                 "if non-zero, the option enables ECC support and specifies "
  84                 "ECC buffer size in bytes (1 is a special value, means 16 "
  85                 "bytes ECC)");
  86
  87 struct ramoops_context {
  88         struct persistent_ram_zone **przs;
  89         struct persistent_ram_zone *cprz;
  90         struct persistent_ram_zone *fprz;
  91         struct persistent_ram_zone *mprz;
  92         phys_addr_t phys_addr;
  93         unsigned long size;
  94         unsigned int memtype;
  95         size_t record_size;
  96         size_t console_size;
  97         size_t ftrace_size;
  98         size_t pmsg_size;
  99         int dump_oops;
 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 ftrace_read_cnt;
 107         unsigned int pmsg_read_cnt;
 108         struct pstore_info pstore;
 109 };
 110
 111 static struct platform_device *dummy;
 112 static struct ramoops_platform_data *dummy_data;
 113
 114 static int ramoops_pstore_open(struct pstore_info *psi)
 115 {
 116         struct ramoops_context *cxt = psi->data;
 117
 118         cxt->dump_read_cnt = 0;
 119         cxt->console_read_cnt = 0;
 120         cxt->ftrace_read_cnt = 0;
 121         cxt->pmsg_read_cnt = 0;
 122         return 0;
 123 }
 124
 125 static struct persistent_ram_zone *
 126 ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
 127                      u64 *id,
 128                      enum pstore_type_id *typep, enum pstore_type_id type,
 129                      bool update)
 130 {
 131         struct persistent_ram_zone *prz;
 132         int i = (*c)++;
 133
 134         if (i >= max)
 135                 return NULL;
 136
 137         prz = przs[i];
 138         if (!prz)
 139                 return NULL;
 140
 141         /* Update old/shadowed buffer. */
 142         if (update)
 143                 persistent_ram_save_old(prz);
 144
 145         if (!persistent_ram_old_size(prz))
 146                 return NULL;
 147
 148         *typep = type;
 149         *id = i;
 150
 151         return prz;
 152 }
 153
 154 static int ramoops_read_kmsg_hdr(char *buffer, struct timespec *time,
 155                                   bool *compressed)
 156 {
 157         char data_type;
 158         int header_length = 0;
 159
 160         if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n%n", &time->tv_sec,
 161                         &time->tv_nsec, &data_type, &header_length) == 3) {
 162                 if (data_type == 'C')
 163                         *compressed = true;
 164                 else
 165                         *compressed = false;
 166         } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n%n",
 167                         &time->tv_sec, &time->tv_nsec, &header_length) == 2) {
 168                         *compressed = false;
 169         } else {
 170                 time->tv_sec = 0;
 171                 time->tv_nsec = 0;
 172                 *compressed = false;
 173         }
 174         return header_length;
 175 }
 176
 177 static bool prz_ok(struct persistent_ram_zone *prz)
 178 {
 179         return !!prz && !!(persistent_ram_old_size(prz) +
 180                            persistent_ram_ecc_string(prz, NULL, 0));
 181 }
 182
 183 static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
 184                                    int *count, struct timespec *time,
 185                                    char **buf, bool *compressed,
 186                                    struct pstore_info *psi)
 187 {
 188         ssize_t size;
 189         ssize_t ecc_notice_size;
 190         struct ramoops_context *cxt = psi->data;
 191         struct persistent_ram_zone *prz = NULL;
 192         int header_length = 0;
 193
 194         /* Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but
 195          * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have
 196          * valid time stamps, so it is initialized to zero.
 197          */
 198         time->tv_sec = 0;
 199         time->tv_nsec = 0;
 200         *compressed = false;
 201
 202         /* Find the next valid persistent_ram_zone for DMESG */
 203         while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) {
 204                 prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,
 205                                            cxt->max_dump_cnt, id, type,
 206                                            PSTORE_TYPE_DMESG, 1);
 207                 if (!prz_ok(prz))
 208                         continue;
 209                 header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz),
 210                                                       time, compressed);
 211                 /* Clear and skip this DMESG record if it has no valid header */
 212                 if (!header_length) {
 213                         persistent_ram_free_old(prz);
 214                         persistent_ram_zap(prz);
 215                         prz = NULL;
 216                 }
 217         }
 218
 219         if (!prz_ok(prz))
 220                 prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
 221                                            1, id, type, PSTORE_TYPE_CONSOLE, 0);
 222         if (!prz_ok(prz))
 223                 prz = ramoops_get_next_prz(&cxt->fprz, &cxt->ftrace_read_cnt,
 224                                            1, id, type, PSTORE_TYPE_FTRACE, 0);
 225         if (!prz_ok(prz))
 226                 prz = ramoops_get_next_prz(&cxt->mprz, &cxt->pmsg_read_cnt,
 227                                            1, id, type, PSTORE_TYPE_PMSG, 0);
 228         if (!prz_ok(prz))
 229                 return 0;
 230
 231         size = persistent_ram_old_size(prz) - header_length;
 232
 233         /* ECC correction notice */
 234         ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
 235
 236         *buf = kmalloc(size + ecc_notice_size + 1, GFP_KERNEL);
 237         if (*buf == NULL)
 238                 return -ENOMEM;
 239
 240         memcpy(*buf, (char *)persistent_ram_old(prz) + header_length, size);
 241         persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1);
 242
 243         return size + ecc_notice_size;
 244 }
 245
 246 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
 247                                      bool compressed)
 248 {
 249         char *hdr;
 250         struct timespec timestamp;
 251         size_t len;
 252
 253         /* Report zeroed timestamp if called before timekeeping has resumed. */
 254         if (__getnstimeofday(&timestamp)) {
 255                 timestamp.tv_sec = 0;
 256                 timestamp.tv_nsec = 0;
 257         }
 258         hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
 259                 (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000),
 260                 compressed ? 'C' : 'D');
 261         WARN_ON_ONCE(!hdr);
 262         len = hdr ? strlen(hdr) : 0;
 263         persistent_ram_write(prz, hdr, len);
 264         kfree(hdr);
 265
 266         return len;
 267 }
 268
 269 static int notrace ramoops_pstore_write_buf(enum pstore_type_id type,
 270                                             enum kmsg_dump_reason reason,
 271                                             u64 *id, unsigned int part,
 272                                             const char *buf,
 273                                             bool compressed, size_t size,
 274                                             struct pstore_info *psi)
 275 {
 276         struct ramoops_context *cxt = psi->data;
 277         struct persistent_ram_zone *prz;
 278         size_t hlen;
 279
 280         if (type == PSTORE_TYPE_CONSOLE) {
 281                 if (!cxt->cprz)
 282                         return -ENOMEM;
 283                 persistent_ram_write(cxt->cprz, buf, size);
 284                 return 0;
 285         } else if (type == PSTORE_TYPE_FTRACE) {
 286                 if (!cxt->fprz)
 287                         return -ENOMEM;
 288                 persistent_ram_write(cxt->fprz, buf, size);
 289                 return 0;
 290         } else if (type == PSTORE_TYPE_PMSG) {
 291                 if (!cxt->mprz)
 292                         return -ENOMEM;
 293                 persistent_ram_write(cxt->mprz, buf, size);
 294                 return 0;
 295         }
 296
 297         if (type != PSTORE_TYPE_DMESG)
 298                 return -EINVAL;
 299
 300         /* Out of the various dmesg dump types, ramoops is currently designed
 301          * to only store crash logs, rather than storing general kernel logs.
 302          */
 303         if (reason != KMSG_DUMP_OOPS &&
 304             reason != KMSG_DUMP_PANIC)
 305                 return -EINVAL;
 306
 307         /* Skip Oopes when configured to do so. */
 308         if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
 309                 return -EINVAL;
 310
 311         /* Explicitly only take the first part of any new crash.
 312          * If our buffer is larger than kmsg_bytes, this can never happen,
 313          * and if our buffer is smaller than kmsg_bytes, we don't want the
 314          * report split across multiple records.
 315          */
 316         if (part != 1)
 317                 return -ENOSPC;
 318
 319         if (!cxt->przs)
 320                 return -ENOSPC;
 321
 322         prz = cxt->przs[cxt->dump_write_cnt];
 323
 324         hlen = ramoops_write_kmsg_hdr(prz, compressed);
 325         if (size + hlen > prz->buffer_size)
 326                 size = prz->buffer_size - hlen;
 327         persistent_ram_write(prz, buf, size);
 328
 329         cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
 330
 331         return 0;
 332 }
 333
 334 static int notrace ramoops_pstore_write_buf_user(enum pstore_type_id type,
 335                                                  enum kmsg_dump_reason reason,
 336                                                  u64 *id, unsigned int part,
 337                                                  const char __user *buf,
 338                                                  bool compressed, size_t size,
 339                                                  struct pstore_info *psi)
 340 {
 341         if (type == PSTORE_TYPE_PMSG) {
 342                 struct ramoops_context *cxt = psi->data;
 343
 344                 if (!cxt->mprz)
 345                         return -ENOMEM;
 346                 return persistent_ram_write_user(cxt->mprz, buf, size);
 347         }
 348
 349         return -EINVAL;
 350 }
 351
 352 static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count,
 353                                 struct timespec time, struct pstore_info *psi)
 354 {
 355         struct ramoops_context *cxt = psi->data;
 356         struct persistent_ram_zone *prz;
 357
 358         switch (type) {
 359         case PSTORE_TYPE_DMESG:
 360                 if (id >= cxt->max_dump_cnt)
 361                         return -EINVAL;
 362                 prz = cxt->przs[id];
 363                 break;
 364         case PSTORE_TYPE_CONSOLE:
 365                 prz = cxt->cprz;
 366                 break;
 367         case PSTORE_TYPE_FTRACE:
 368                 prz = cxt->fprz;
 369                 break;
 370         case PSTORE_TYPE_PMSG:
 371                 prz = cxt->mprz;
 372                 break;
 373         default:
 374                 return -EINVAL;
 375         }
 376
 377         persistent_ram_free_old(prz);
 378         persistent_ram_zap(prz);
 379
 380         return 0;
 381 }
 382
 383 static struct ramoops_context oops_cxt = {
 384         .pstore = {
 385                 .owner  = THIS_MODULE,
 386                 .name   = "ramoops",
 387                 .open   = ramoops_pstore_open,
 388                 .read   = ramoops_pstore_read,
 389                 .write_buf      = ramoops_pstore_write_buf,
 390                 .write_buf_user = ramoops_pstore_write_buf_user,
 391                 .erase  = ramoops_pstore_erase,
 392         },
 393 };
 394
 395 static void ramoops_free_przs(struct ramoops_context *cxt)
 396 {
 397         int i;
 398
 399         if (!cxt->przs)
 400                 return;
 401
 402         for (i = 0; i < cxt->max_dump_cnt; i++)
 403                 persistent_ram_free(cxt->przs[i]);
 404
 405         kfree(cxt->przs);
 406         cxt->max_dump_cnt = 0;
 407 }
 408
 409 static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
 410                              phys_addr_t *paddr, size_t dump_mem_sz)
 411 {
 412         int err = -ENOMEM;
 413         int i;
 414
 415         if (!cxt->record_size)
 416                 return 0;
 417
 418         if (*paddr + dump_mem_sz - cxt->phys_addr > cxt->size) {
 419                 dev_err(dev, "no room for dumps\n");
 420                 return -ENOMEM;
 421         }
 422
 423         cxt->max_dump_cnt = dump_mem_sz / cxt->record_size;
 424         if (!cxt->max_dump_cnt)
 425                 return -ENOMEM;
 426
 427         cxt->przs = kzalloc(sizeof(*cxt->przs) * cxt->max_dump_cnt,
 428                              GFP_KERNEL);
 429         if (!cxt->przs) {
 430                 dev_err(dev, "failed to initialize a prz array for dumps\n");
 431                 goto fail_mem;
 432         }
 433
 434         for (i = 0; i < cxt->max_dump_cnt; i++) {
 435                 cxt->przs[i] = persistent_ram_new(*paddr, cxt->record_size, 0,
 436                                                   &cxt->ecc_info,
 437                                                   cxt->memtype);
 438                 if (IS_ERR(cxt->przs[i])) {
 439                         err = PTR_ERR(cxt->przs[i]);
 440                         dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
 441                                 cxt->record_size, (unsigned long long)*paddr, err);
 442
 443                         while (i > 0) {
 444                                 i--;
 445                                 persistent_ram_free(cxt->przs[i]);
 446                         }
 447                         goto fail_prz;
 448                 }
 449                 *paddr += cxt->record_size;
 450         }
 451
 452         return 0;
 453 fail_prz:
 454         kfree(cxt->przs);
 455 fail_mem:
 456         cxt->max_dump_cnt = 0;
 457         return err;
 458 }
 459
 460 static int ramoops_init_prz(struct device *dev, struct ramoops_context *cxt,
 461                             struct persistent_ram_zone **prz,
 462                             phys_addr_t *paddr, size_t sz, u32 sig)
 463 {
 464         if (!sz)
 465                 return 0;
 466
 467         if (*paddr + sz - cxt->phys_addr > cxt->size) {
 468                 dev_err(dev, "no room for mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
 469                         sz, (unsigned long long)*paddr,
 470                         cxt->size, (unsigned long long)cxt->phys_addr);
 471                 return -ENOMEM;
 472         }
 473
 474         *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info, cxt->memtype);
 475         if (IS_ERR(*prz)) {
 476                 int err = PTR_ERR(*prz);
 477
 478                 dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
 479                         sz, (unsigned long long)*paddr, err);
 480                 return err;
 481         }
 482
 483         persistent_ram_zap(*prz);
 484
 485         *paddr += sz;
 486
 487         return 0;
 488 }
 489
 490 void notrace ramoops_console_write_buf(const char *buf, size_t size)
 491 {
 492         struct ramoops_context *cxt = &oops_cxt;
 493         persistent_ram_write(cxt->cprz, buf, size);
 494 }
 495
 496 static int ramoops_parse_dt_size(struct platform_device *pdev,
 497                 const char *propname, unsigned long *val)
 498 {
 499         u64 val64;
 500         int ret;
 501
 502         ret = of_property_read_u64(pdev->dev.of_node, propname, &val64);
 503         if (ret == -EINVAL) {
 504                 *val = 0;
 505                 return 0;
 506         } else if (ret != 0) {
 507                 dev_err(&pdev->dev, "failed to parse property %s: %d\n",
 508                                 propname, ret);
 509                 return ret;
 510         }
 511
 512         if (val64 > ULONG_MAX) {
 513                 dev_err(&pdev->dev, "invalid %s %llu\n", propname, val64);
 514                 return -EOVERFLOW;
 515         }
 516
 517         *val = val64;
 518         return 0;
 519 }
 520
 521 static int ramoops_parse_dt(struct platform_device *pdev,
 522                 struct ramoops_platform_data *pdata)
 523 {
 524         struct device_node *of_node = pdev->dev.of_node;
 525         struct device_node *mem_region;
 526         struct resource res;
 527         u32 ecc_size;
 528         int ret;
 529
 530         dev_dbg(&pdev->dev, "using Device Tree\n");
 531
 532         mem_region = of_parse_phandle(of_node, "memory-region", 0);
 533         if (!mem_region) {
 534                 dev_err(&pdev->dev, "no memory-region phandle\n");
 535                 return -ENODEV;
 536         }
 537
 538         ret = of_address_to_resource(mem_region, 0, &res);
 539         of_node_put(mem_region);
 540         if (ret) {
 541                 dev_err(&pdev->dev, "failed to translate memory-region to resource: %d\n",
 542                                 ret);
 543                 return ret;
 544         }
 545
 546         pdata->mem_size = resource_size(&res);
 547         pdata->mem_address = res.start;
 548         pdata->mem_type = of_property_read_bool(of_node, "unbuffered");
 549         pdata->dump_oops = !of_property_read_bool(of_node, "no-dump-oops");
 550
 551         ret = ramoops_parse_dt_size(pdev, "record-size", &pdata->record_size);
 552         if (ret < 0)
 553                 return ret;
 554
 555         ret = ramoops_parse_dt_size(pdev, "console-size", &pdata->console_size);
 556         if (ret < 0)
 557                 return ret;
 558
 559         ret = ramoops_parse_dt_size(pdev, "ftrace-size", &pdata->ftrace_size);
 560         if (ret < 0)
 561                 return ret;
 562
 563         ret = ramoops_parse_dt_size(pdev, "pmsg-size", &pdata->pmsg_size);
 564         if (ret < 0)
 565                 return ret;
 566
 567         ret = of_property_read_u32(of_node, "ecc-size", &ecc_size);
 568         if (ret == 0) {
 569                 if (ecc_size > INT_MAX) {
 570                         dev_err(&pdev->dev, "invalid ecc-size %u\n", ecc_size);
 571                         return -EOVERFLOW;
 572                 }
 573                 pdata->ecc_info.ecc_size = ecc_size;
 574         } else if (ret != -EINVAL) {
 575                 return ret;
 576         }
 577
 578         return 0;
 579 }
 580
 581 static int ramoops_probe(struct platform_device *pdev)
 582 {
 583         struct device *dev = &pdev->dev;
 584         struct ramoops_platform_data *pdata = pdev->dev.platform_data;
 585         struct ramoops_context *cxt = &oops_cxt;
 586         size_t dump_mem_sz;
 587         phys_addr_t paddr;
 588         int err = -EINVAL;
 589
 590         if (dev->of_node && !pdata) {
 591                 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 592                 if (!pdata) {
 593                         err = -ENOMEM;
 594                         goto fail_out;
 595                 }
 596
 597                 err = ramoops_parse_dt(pdev, pdata);
 598                 if (err < 0)
 599                         goto fail_out;
 600         }
 601
 602         /* Only a single ramoops area allowed at a time, so fail extra
 603          * probes.
 604          */
 605         if (cxt->max_dump_cnt)
 606                 goto fail_out;
 607
 608         if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
 609                         !pdata->ftrace_size && !pdata->pmsg_size)) {
 610                 pr_err("The memory size and the record/console size must be "
 611                         "non-zero\n");
 612                 goto fail_out;
 613         }
 614
 615         if (pdata->record_size && !is_power_of_2(pdata->record_size))
 616                 pdata->record_size = rounddown_pow_of_two(pdata->record_size);
 617         if (pdata->console_size && !is_power_of_2(pdata->console_size))
 618                 pdata->console_size = rounddown_pow_of_two(pdata->console_size);
 619         if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))
 620                 pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);
 621         if (pdata->pmsg_size && !is_power_of_2(pdata->pmsg_size))
 622                 pdata->pmsg_size = rounddown_pow_of_two(pdata->pmsg_size);
 623
 624         cxt->size = pdata->mem_size;
 625         cxt->phys_addr = pdata->mem_address;
 626         cxt->memtype = pdata->mem_type;
 627         cxt->record_size = pdata->record_size;
 628         cxt->console_size = pdata->console_size;
 629         cxt->ftrace_size = pdata->ftrace_size;
 630         cxt->pmsg_size = pdata->pmsg_size;
 631         cxt->dump_oops = pdata->dump_oops;
 632         cxt->ecc_info = pdata->ecc_info;
 633
 634         paddr = cxt->phys_addr;
 635
 636         dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size
 637                         - cxt->pmsg_size;
 638         err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
 639         if (err)
 640                 goto fail_out;
 641
 642         err = ramoops_init_prz(dev, cxt, &cxt->cprz, &paddr,
 643                                cxt->console_size, 0);
 644         if (err)
 645                 goto fail_init_cprz;
 646
 647         err = ramoops_init_prz(dev, cxt, &cxt->fprz, &paddr, cxt->ftrace_size,
 648                                LINUX_VERSION_CODE);
 649         if (err)
 650                 goto fail_init_fprz;
 651
 652         err = ramoops_init_prz(dev, cxt, &cxt->mprz, &paddr, cxt->pmsg_size, 0);
 653         if (err)
 654                 goto fail_init_mprz;
 655
 656         cxt->pstore.data = cxt;
 657         /*
 658          * Console can handle any buffer size, so prefer LOG_LINE_MAX. If we
 659          * have to handle dumps, we must have at least record_size buffer. And
 660          * for ftrace, bufsize is irrelevant (if bufsize is 0, buf will be
 661          * ZERO_SIZE_PTR).
 662          */
 663         if (cxt->console_size)
 664                 cxt->pstore.bufsize = 1024; /* LOG_LINE_MAX */
 665         cxt->pstore.bufsize = max(cxt->record_size, cxt->pstore.bufsize);
 666         cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
 667         spin_lock_init(&cxt->pstore.buf_lock);
 668         if (!cxt->pstore.buf) {
 669                 pr_err("cannot allocate pstore buffer\n");
 670                 err = -ENOMEM;
 671                 goto fail_clear;
 672         }
 673
 674         err = pstore_register(&cxt->pstore);
 675         if (err) {
 676                 pr_err("registering with pstore failed\n");
 677                 goto fail_buf;
 678         }
 679
 680         /*
 681          * Update the module parameter variables as well so they are visible
 682          * through /sys/module/ramoops/parameters/
 683          */
 684         mem_size = pdata->mem_size;
 685         mem_address = pdata->mem_address;
 686         record_size = pdata->record_size;
 687         dump_oops = pdata->dump_oops;
 688         ramoops_console_size = pdata->console_size;
 689         ramoops_pmsg_size = pdata->pmsg_size;
 690         ramoops_ftrace_size = pdata->ftrace_size;
 691
 692         pr_info("attached 0x%lx@0x%llx, ecc: %d/%d\n",
 693                 cxt->size, (unsigned long long)cxt->phys_addr,
 694                 cxt->ecc_info.ecc_size, cxt->ecc_info.block_size);
 695
 696         return 0;
 697
 698 fail_buf:
 699         kfree(cxt->pstore.buf);
 700 fail_clear:
 701         cxt->pstore.bufsize = 0;
 702         kfree(cxt->mprz);
 703 fail_init_mprz:
 704         kfree(cxt->fprz);
 705 fail_init_fprz:
 706         kfree(cxt->cprz);
 707 fail_init_cprz:
 708         ramoops_free_przs(cxt);
 709 fail_out:
 710         return err;
 711 }
 712
 713 static int ramoops_remove(struct platform_device *pdev)
 714 {
 715         struct ramoops_context *cxt = &oops_cxt;
 716
 717         pstore_unregister(&cxt->pstore);
 718
 719         kfree(cxt->pstore.buf);
 720         cxt->pstore.bufsize = 0;
 721
 722         persistent_ram_free(cxt->mprz);
 723         persistent_ram_free(cxt->fprz);
 724         persistent_ram_free(cxt->cprz);
 725         ramoops_free_przs(cxt);
 726
 727         return 0;
 728 }
 729
 730 static const struct of_device_id dt_match[] = {
 731         { .compatible = "ramoops" },
 732         {}
 733 };
 734
 735 static struct platform_driver ramoops_driver = {
 736         .probe          = ramoops_probe,
 737         .remove         = ramoops_remove,
 738         .driver         = {
 739                 .name           = "ramoops",
 740                 .of_match_table = dt_match,
 741         },
 742 };
 743
 744 static void ramoops_register_dummy(void)
 745 {
 746         if (!mem_size)
 747                 return;
 748
 749         pr_info("using module parameters\n");
 750
 751         dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
 752         if (!dummy_data) {
 753                 pr_info("could not allocate pdata\n");
 754                 return;
 755         }
 756
 757         dummy_data->mem_size = mem_size;
 758         dummy_data->mem_address = mem_address;
 759         dummy_data->mem_type = mem_type;
 760         dummy_data->record_size = record_size;
 761         dummy_data->console_size = ramoops_console_size;
 762         dummy_data->ftrace_size = ramoops_ftrace_size;
 763         dummy_data->pmsg_size = ramoops_pmsg_size;
 764         dummy_data->dump_oops = dump_oops;
 765         /*
 766          * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
 767          * (using 1 byte for ECC isn't much of use anyway).
 768          */
 769         dummy_data->ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : ramoops_ecc;
 770
 771         dummy = platform_device_register_data(NULL, "ramoops", -1,
 772                         dummy_data, sizeof(struct ramoops_platform_data));
 773         if (IS_ERR(dummy)) {
 774                 pr_info("could not create platform device: %ld\n",
 775                         PTR_ERR(dummy));
 776         }
 777 }
 778
 779 static int __init ramoops_init(void)
 780 {
 781         ramoops_register_dummy();
 782         return platform_driver_register(&ramoops_driver);
 783 }
 784 postcore_initcall(ramoops_init);
 785
 786 static void __exit ramoops_exit(void)
 787 {
 788         platform_driver_unregister(&ramoops_driver);
 789         platform_device_unregister(dummy);
 790         kfree(dummy_data);
 791 }
 792 module_exit(ramoops_exit);
 793
 794 MODULE_LICENSE("GPL");
 795 MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
 796 MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");