1 /* 2 * c 2001 PPC 64 Team, IBM Corp 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * /dev/nvram driver for PPC64 10 * 11 * This perhaps should live in drivers/char 12 * 13 * TODO: Split the /dev/nvram part (that one can use 14 * drivers/char/generic_nvram.c) from the arch & partition 15 * parsing code. 16 */ 17 18 #include <linux/module.h> 19 20 #include <linux/types.h> 21 #include <linux/errno.h> 22 #include <linux/fs.h> 23 #include <linux/miscdevice.h> 24 #include <linux/fcntl.h> 25 #include <linux/nvram.h> 26 #include <linux/init.h> 27 #include <linux/slab.h> 28 #include <linux/spinlock.h> 29 #include <linux/kmsg_dump.h> 30 #include <linux/pagemap.h> 31 #include <linux/pstore.h> 32 #include <linux/zlib.h> 33 #include <asm/uaccess.h> 34 #include <asm/nvram.h> 35 #include <asm/rtas.h> 36 #include <asm/prom.h> 37 #include <asm/machdep.h> 38 39 #undef DEBUG_NVRAM 40 41 #define NVRAM_HEADER_LEN sizeof(struct nvram_header) 42 #define NVRAM_BLOCK_LEN NVRAM_HEADER_LEN 43 44 /* If change this size, then change the size of NVNAME_LEN */ 45 struct nvram_header { 46 unsigned char signature; 47 unsigned char checksum; 48 unsigned short length; 49 /* Terminating null required only for names < 12 chars. */ 50 char name[12]; 51 }; 52 53 struct nvram_partition { 54 struct list_head partition; 55 struct nvram_header header; 56 unsigned int index; 57 }; 58 59 static LIST_HEAD(nvram_partitions); 60 61 #ifdef CONFIG_PPC_PSERIES 62 struct nvram_os_partition rtas_log_partition = { 63 .name = "ibm,rtas-log", 64 .req_size = 2079, 65 .min_size = 1055, 66 .index = -1, 67 .os_partition = true 68 }; 69 #endif 70 71 struct nvram_os_partition oops_log_partition = { 72 .name = "lnx,oops-log", 73 .req_size = 4000, 74 .min_size = 2000, 75 .index = -1, 76 .os_partition = true 77 }; 78 79 static const char *nvram_os_partitions[] = { 80 #ifdef CONFIG_PPC_PSERIES 81 "ibm,rtas-log", 82 #endif 83 "lnx,oops-log", 84 NULL 85 }; 86 87 static void oops_to_nvram(struct kmsg_dumper *dumper, 88 enum kmsg_dump_reason reason); 89 90 static struct kmsg_dumper nvram_kmsg_dumper = { 91 .dump = oops_to_nvram 92 }; 93 94 /* 95 * For capturing and compressing an oops or panic report... 96 97 * big_oops_buf[] holds the uncompressed text we're capturing. 98 * 99 * oops_buf[] holds the compressed text, preceded by a oops header. 100 * oops header has u16 holding the version of oops header (to differentiate 101 * between old and new format header) followed by u16 holding the length of 102 * the compressed* text (*Or uncompressed, if compression fails.) and u64 103 * holding the timestamp. oops_buf[] gets written to NVRAM. 104 * 105 * oops_log_info points to the header. oops_data points to the compressed text. 106 * 107 * +- oops_buf 108 * | +- oops_data 109 * v v 110 * +-----------+-----------+-----------+------------------------+ 111 * | version | length | timestamp | text | 112 * | (2 bytes) | (2 bytes) | (8 bytes) | (oops_data_sz bytes) | 113 * +-----------+-----------+-----------+------------------------+ 114 * ^ 115 * +- oops_log_info 116 * 117 * We preallocate these buffers during init to avoid kmalloc during oops/panic. 118 */ 119 static size_t big_oops_buf_sz; 120 static char *big_oops_buf, *oops_buf; 121 static char *oops_data; 122 static size_t oops_data_sz; 123 124 /* Compression parameters */ 125 #define COMPR_LEVEL 6 126 #define WINDOW_BITS 12 127 #define MEM_LEVEL 4 128 static struct z_stream_s stream; 129 130 #ifdef CONFIG_PSTORE 131 #ifdef CONFIG_PPC_POWERNV 132 static struct nvram_os_partition skiboot_partition = { 133 .name = "ibm,skiboot", 134 .index = -1, 135 .os_partition = false 136 }; 137 #endif 138 139 #ifdef CONFIG_PPC_PSERIES 140 static struct nvram_os_partition of_config_partition = { 141 .name = "of-config", 142 .index = -1, 143 .os_partition = false 144 }; 145 #endif 146 147 static struct nvram_os_partition common_partition = { 148 .name = "common", 149 .index = -1, 150 .os_partition = false 151 }; 152 153 static enum pstore_type_id nvram_type_ids[] = { 154 PSTORE_TYPE_DMESG, 155 PSTORE_TYPE_PPC_COMMON, 156 -1, 157 -1, 158 -1 159 }; 160 static int read_type; 161 #endif 162 163 /* nvram_write_os_partition 164 * 165 * We need to buffer the error logs into nvram to ensure that we have 166 * the failure information to decode. If we have a severe error there 167 * is no way to guarantee that the OS or the machine is in a state to 168 * get back to user land and write the error to disk. For example if 169 * the SCSI device driver causes a Machine Check by writing to a bad 170 * IO address, there is no way of guaranteeing that the device driver 171 * is in any state that is would also be able to write the error data 172 * captured to disk, thus we buffer it in NVRAM for analysis on the 173 * next boot. 174 * 175 * In NVRAM the partition containing the error log buffer will looks like: 176 * Header (in bytes): 177 * +-----------+----------+--------+------------+------------------+ 178 * | signature | checksum | length | name | data | 179 * |0 |1 |2 3|4 15|16 length-1| 180 * +-----------+----------+--------+------------+------------------+ 181 * 182 * The 'data' section would look like (in bytes): 183 * +--------------+------------+-----------------------------------+ 184 * | event_logged | sequence # | error log | 185 * |0 3|4 7|8 error_log_size-1| 186 * +--------------+------------+-----------------------------------+ 187 * 188 * event_logged: 0 if event has not been logged to syslog, 1 if it has 189 * sequence #: The unique sequence # for each event. (until it wraps) 190 * error log: The error log from event_scan 191 */ 192 int nvram_write_os_partition(struct nvram_os_partition *part, 193 char *buff, int length, 194 unsigned int err_type, 195 unsigned int error_log_cnt) 196 { 197 int rc; 198 loff_t tmp_index; 199 struct err_log_info info; 200 201 if (part->index == -1) 202 return -ESPIPE; 203 204 if (length > part->size) 205 length = part->size; 206 207 info.error_type = cpu_to_be32(err_type); 208 info.seq_num = cpu_to_be32(error_log_cnt); 209 210 tmp_index = part->index; 211 212 rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), 213 &tmp_index); 214 if (rc <= 0) { 215 pr_err("%s: Failed nvram_write (%d)\n", __func__, rc); 216 return rc; 217 } 218 219 rc = ppc_md.nvram_write(buff, length, &tmp_index); 220 if (rc <= 0) { 221 pr_err("%s: Failed nvram_write (%d)\n", __func__, rc); 222 return rc; 223 } 224 225 return 0; 226 } 227 228 /* nvram_read_partition 229 * 230 * Reads nvram partition for at most 'length' 231 */ 232 int nvram_read_partition(struct nvram_os_partition *part, char *buff, 233 int length, unsigned int *err_type, 234 unsigned int *error_log_cnt) 235 { 236 int rc; 237 loff_t tmp_index; 238 struct err_log_info info; 239 240 if (part->index == -1) 241 return -1; 242 243 if (length > part->size) 244 length = part->size; 245 246 tmp_index = part->index; 247 248 if (part->os_partition) { 249 rc = ppc_md.nvram_read((char *)&info, 250 sizeof(struct err_log_info), 251 &tmp_index); 252 if (rc <= 0) { 253 pr_err("%s: Failed nvram_read (%d)\n", __func__, rc); 254 return rc; 255 } 256 } 257 258 rc = ppc_md.nvram_read(buff, length, &tmp_index); 259 if (rc <= 0) { 260 pr_err("%s: Failed nvram_read (%d)\n", __func__, rc); 261 return rc; 262 } 263 264 if (part->os_partition) { 265 *error_log_cnt = be32_to_cpu(info.seq_num); 266 *err_type = be32_to_cpu(info.error_type); 267 } 268 269 return 0; 270 } 271 272 /* nvram_init_os_partition 273 * 274 * This sets up a partition with an "OS" signature. 275 * 276 * The general strategy is the following: 277 * 1.) If a partition with the indicated name already exists... 278 * - If it's large enough, use it. 279 * - Otherwise, recycle it and keep going. 280 * 2.) Search for a free partition that is large enough. 281 * 3.) If there's not a free partition large enough, recycle any obsolete 282 * OS partitions and try again. 283 * 4.) Will first try getting a chunk that will satisfy the requested size. 284 * 5.) If a chunk of the requested size cannot be allocated, then try finding 285 * a chunk that will satisfy the minum needed. 286 * 287 * Returns 0 on success, else -1. 288 */ 289 int __init nvram_init_os_partition(struct nvram_os_partition *part) 290 { 291 loff_t p; 292 int size; 293 294 /* Look for ours */ 295 p = nvram_find_partition(part->name, NVRAM_SIG_OS, &size); 296 297 /* Found one but too small, remove it */ 298 if (p && size < part->min_size) { 299 pr_info("nvram: Found too small %s partition," 300 " removing it...\n", part->name); 301 nvram_remove_partition(part->name, NVRAM_SIG_OS, NULL); 302 p = 0; 303 } 304 305 /* Create one if we didn't find */ 306 if (!p) { 307 p = nvram_create_partition(part->name, NVRAM_SIG_OS, 308 part->req_size, part->min_size); 309 if (p == -ENOSPC) { 310 pr_info("nvram: No room to create %s partition, " 311 "deleting any obsolete OS partitions...\n", 312 part->name); 313 nvram_remove_partition(NULL, NVRAM_SIG_OS, 314 nvram_os_partitions); 315 p = nvram_create_partition(part->name, NVRAM_SIG_OS, 316 part->req_size, part->min_size); 317 } 318 } 319 320 if (p <= 0) { 321 pr_err("nvram: Failed to find or create %s" 322 " partition, err %d\n", part->name, (int)p); 323 return -1; 324 } 325 326 part->index = p; 327 part->size = nvram_get_partition_size(p) - sizeof(struct err_log_info); 328 329 return 0; 330 } 331 332 /* Derived from logfs_compress() */ 333 static int nvram_compress(const void *in, void *out, size_t inlen, 334 size_t outlen) 335 { 336 int err, ret; 337 338 ret = -EIO; 339 err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS, 340 MEM_LEVEL, Z_DEFAULT_STRATEGY); 341 if (err != Z_OK) 342 goto error; 343 344 stream.next_in = in; 345 stream.avail_in = inlen; 346 stream.total_in = 0; 347 stream.next_out = out; 348 stream.avail_out = outlen; 349 stream.total_out = 0; 350 351 err = zlib_deflate(&stream, Z_FINISH); 352 if (err != Z_STREAM_END) 353 goto error; 354 355 err = zlib_deflateEnd(&stream); 356 if (err != Z_OK) 357 goto error; 358 359 if (stream.total_out >= stream.total_in) 360 goto error; 361 362 ret = stream.total_out; 363 error: 364 return ret; 365 } 366 367 /* Compress the text from big_oops_buf into oops_buf. */ 368 static int zip_oops(size_t text_len) 369 { 370 struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; 371 int zipped_len = nvram_compress(big_oops_buf, oops_data, text_len, 372 oops_data_sz); 373 if (zipped_len < 0) { 374 pr_err("nvram: compression failed; returned %d\n", zipped_len); 375 pr_err("nvram: logging uncompressed oops/panic report\n"); 376 return -1; 377 } 378 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 379 oops_hdr->report_length = cpu_to_be16(zipped_len); 380 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 381 return 0; 382 } 383 384 #ifdef CONFIG_PSTORE 385 static int nvram_pstore_open(struct pstore_info *psi) 386 { 387 /* Reset the iterator to start reading partitions again */ 388 read_type = -1; 389 return 0; 390 } 391 392 /** 393 * nvram_pstore_write - pstore write callback for nvram 394 * @type: Type of message logged 395 * @reason: reason behind dump (oops/panic) 396 * @id: identifier to indicate the write performed 397 * @part: pstore writes data to registered buffer in parts, 398 * part number will indicate the same. 399 * @count: Indicates oops count 400 * @compressed: Flag to indicate the log is compressed 401 * @size: number of bytes written to the registered buffer 402 * @psi: registered pstore_info structure 403 * 404 * Called by pstore_dump() when an oops or panic report is logged in the 405 * printk buffer. 406 * Returns 0 on successful write. 407 */ 408 static int nvram_pstore_write(enum pstore_type_id type, 409 enum kmsg_dump_reason reason, 410 u64 *id, unsigned int part, int count, 411 bool compressed, size_t size, 412 struct pstore_info *psi) 413 { 414 int rc; 415 unsigned int err_type = ERR_TYPE_KERNEL_PANIC; 416 struct oops_log_info *oops_hdr = (struct oops_log_info *) oops_buf; 417 418 /* part 1 has the recent messages from printk buffer */ 419 if (part > 1 || (type != PSTORE_TYPE_DMESG)) 420 return -1; 421 422 if (clobbering_unread_rtas_event()) 423 return -1; 424 425 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 426 oops_hdr->report_length = cpu_to_be16(size); 427 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 428 429 if (compressed) 430 err_type = ERR_TYPE_KERNEL_PANIC_GZ; 431 432 rc = nvram_write_os_partition(&oops_log_partition, oops_buf, 433 (int) (sizeof(*oops_hdr) + size), err_type, count); 434 435 if (rc != 0) 436 return rc; 437 438 *id = part; 439 return 0; 440 } 441 442 /* 443 * Reads the oops/panic report, rtas, of-config and common partition. 444 * Returns the length of the data we read from each partition. 445 * Returns 0 if we've been called before. 446 */ 447 static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type, 448 int *count, struct timespec *time, char **buf, 449 bool *compressed, struct pstore_info *psi) 450 { 451 struct oops_log_info *oops_hdr; 452 unsigned int err_type, id_no, size = 0; 453 struct nvram_os_partition *part = NULL; 454 char *buff = NULL; 455 int sig = 0; 456 loff_t p; 457 458 read_type++; 459 460 switch (nvram_type_ids[read_type]) { 461 case PSTORE_TYPE_DMESG: 462 part = &oops_log_partition; 463 *type = PSTORE_TYPE_DMESG; 464 break; 465 case PSTORE_TYPE_PPC_COMMON: 466 sig = NVRAM_SIG_SYS; 467 part = &common_partition; 468 *type = PSTORE_TYPE_PPC_COMMON; 469 *id = PSTORE_TYPE_PPC_COMMON; 470 time->tv_sec = 0; 471 time->tv_nsec = 0; 472 break; 473 #ifdef CONFIG_PPC_PSERIES 474 case PSTORE_TYPE_PPC_RTAS: 475 part = &rtas_log_partition; 476 *type = PSTORE_TYPE_PPC_RTAS; 477 time->tv_sec = last_rtas_event; 478 time->tv_nsec = 0; 479 break; 480 case PSTORE_TYPE_PPC_OF: 481 sig = NVRAM_SIG_OF; 482 part = &of_config_partition; 483 *type = PSTORE_TYPE_PPC_OF; 484 *id = PSTORE_TYPE_PPC_OF; 485 time->tv_sec = 0; 486 time->tv_nsec = 0; 487 break; 488 #endif 489 #ifdef CONFIG_PPC_POWERNV 490 case PSTORE_TYPE_PPC_OPAL: 491 sig = NVRAM_SIG_FW; 492 part = &skiboot_partition; 493 *type = PSTORE_TYPE_PPC_OPAL; 494 *id = PSTORE_TYPE_PPC_OPAL; 495 time->tv_sec = 0; 496 time->tv_nsec = 0; 497 break; 498 #endif 499 default: 500 return 0; 501 } 502 503 if (!part->os_partition) { 504 p = nvram_find_partition(part->name, sig, &size); 505 if (p <= 0) { 506 pr_err("nvram: Failed to find partition %s, " 507 "err %d\n", part->name, (int)p); 508 return 0; 509 } 510 part->index = p; 511 part->size = size; 512 } 513 514 buff = kmalloc(part->size, GFP_KERNEL); 515 516 if (!buff) 517 return -ENOMEM; 518 519 if (nvram_read_partition(part, buff, part->size, &err_type, &id_no)) { 520 kfree(buff); 521 return 0; 522 } 523 524 *count = 0; 525 526 if (part->os_partition) 527 *id = id_no; 528 529 if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) { 530 size_t length, hdr_size; 531 532 oops_hdr = (struct oops_log_info *)buff; 533 if (be16_to_cpu(oops_hdr->version) < OOPS_HDR_VERSION) { 534 /* Old format oops header had 2-byte record size */ 535 hdr_size = sizeof(u16); 536 length = be16_to_cpu(oops_hdr->version); 537 time->tv_sec = 0; 538 time->tv_nsec = 0; 539 } else { 540 hdr_size = sizeof(*oops_hdr); 541 length = be16_to_cpu(oops_hdr->report_length); 542 time->tv_sec = be64_to_cpu(oops_hdr->timestamp); 543 time->tv_nsec = 0; 544 } 545 *buf = kmemdup(buff + hdr_size, length, GFP_KERNEL); 546 if (*buf == NULL) 547 return -ENOMEM; 548 kfree(buff); 549 550 if (err_type == ERR_TYPE_KERNEL_PANIC_GZ) 551 *compressed = true; 552 else 553 *compressed = false; 554 return length; 555 } 556 557 *buf = buff; 558 return part->size; 559 } 560 561 static struct pstore_info nvram_pstore_info = { 562 .owner = THIS_MODULE, 563 .name = "nvram", 564 .open = nvram_pstore_open, 565 .read = nvram_pstore_read, 566 .write = nvram_pstore_write, 567 }; 568 569 static int nvram_pstore_init(void) 570 { 571 int rc = 0; 572 573 if (machine_is(pseries)) { 574 nvram_type_ids[2] = PSTORE_TYPE_PPC_RTAS; 575 nvram_type_ids[3] = PSTORE_TYPE_PPC_OF; 576 } else 577 nvram_type_ids[2] = PSTORE_TYPE_PPC_OPAL; 578 579 nvram_pstore_info.buf = oops_data; 580 nvram_pstore_info.bufsize = oops_data_sz; 581 582 spin_lock_init(&nvram_pstore_info.buf_lock); 583 584 rc = pstore_register(&nvram_pstore_info); 585 if (rc && (rc != -EPERM)) 586 /* Print error only when pstore.backend == nvram */ 587 pr_err("nvram: pstore_register() failed, returned %d. " 588 "Defaults to kmsg_dump\n", rc); 589 590 return rc; 591 } 592 #else 593 static int nvram_pstore_init(void) 594 { 595 return -1; 596 } 597 #endif 598 599 void __init nvram_init_oops_partition(int rtas_partition_exists) 600 { 601 int rc; 602 603 rc = nvram_init_os_partition(&oops_log_partition); 604 if (rc != 0) { 605 #ifdef CONFIG_PPC_PSERIES 606 if (!rtas_partition_exists) { 607 pr_err("nvram: Failed to initialize oops partition!"); 608 return; 609 } 610 pr_notice("nvram: Using %s partition to log both" 611 " RTAS errors and oops/panic reports\n", 612 rtas_log_partition.name); 613 memcpy(&oops_log_partition, &rtas_log_partition, 614 sizeof(rtas_log_partition)); 615 #else 616 pr_err("nvram: Failed to initialize oops partition!"); 617 return; 618 #endif 619 } 620 oops_buf = kmalloc(oops_log_partition.size, GFP_KERNEL); 621 if (!oops_buf) { 622 pr_err("nvram: No memory for %s partition\n", 623 oops_log_partition.name); 624 return; 625 } 626 oops_data = oops_buf + sizeof(struct oops_log_info); 627 oops_data_sz = oops_log_partition.size - sizeof(struct oops_log_info); 628 629 rc = nvram_pstore_init(); 630 631 if (!rc) 632 return; 633 634 /* 635 * Figure compression (preceded by elimination of each line's <n> 636 * severity prefix) will reduce the oops/panic report to at most 637 * 45% of its original size. 638 */ 639 big_oops_buf_sz = (oops_data_sz * 100) / 45; 640 big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL); 641 if (big_oops_buf) { 642 stream.workspace = kmalloc(zlib_deflate_workspacesize( 643 WINDOW_BITS, MEM_LEVEL), GFP_KERNEL); 644 if (!stream.workspace) { 645 pr_err("nvram: No memory for compression workspace; " 646 "skipping compression of %s partition data\n", 647 oops_log_partition.name); 648 kfree(big_oops_buf); 649 big_oops_buf = NULL; 650 } 651 } else { 652 pr_err("No memory for uncompressed %s data; " 653 "skipping compression\n", oops_log_partition.name); 654 stream.workspace = NULL; 655 } 656 657 rc = kmsg_dump_register(&nvram_kmsg_dumper); 658 if (rc != 0) { 659 pr_err("nvram: kmsg_dump_register() failed; returned %d\n", rc); 660 kfree(oops_buf); 661 kfree(big_oops_buf); 662 kfree(stream.workspace); 663 } 664 } 665 666 /* 667 * This is our kmsg_dump callback, called after an oops or panic report 668 * has been written to the printk buffer. We want to capture as much 669 * of the printk buffer as possible. First, capture as much as we can 670 * that we think will compress sufficiently to fit in the lnx,oops-log 671 * partition. If that's too much, go back and capture uncompressed text. 672 */ 673 static void oops_to_nvram(struct kmsg_dumper *dumper, 674 enum kmsg_dump_reason reason) 675 { 676 struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; 677 static unsigned int oops_count = 0; 678 static bool panicking = false; 679 static DEFINE_SPINLOCK(lock); 680 unsigned long flags; 681 size_t text_len; 682 unsigned int err_type = ERR_TYPE_KERNEL_PANIC_GZ; 683 int rc = -1; 684 685 switch (reason) { 686 case KMSG_DUMP_RESTART: 687 case KMSG_DUMP_HALT: 688 case KMSG_DUMP_POWEROFF: 689 /* These are almost always orderly shutdowns. */ 690 return; 691 case KMSG_DUMP_OOPS: 692 break; 693 case KMSG_DUMP_PANIC: 694 panicking = true; 695 break; 696 case KMSG_DUMP_EMERG: 697 if (panicking) 698 /* Panic report already captured. */ 699 return; 700 break; 701 default: 702 pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n", 703 __func__, (int) reason); 704 return; 705 } 706 707 if (clobbering_unread_rtas_event()) 708 return; 709 710 if (!spin_trylock_irqsave(&lock, flags)) 711 return; 712 713 if (big_oops_buf) { 714 kmsg_dump_get_buffer(dumper, false, 715 big_oops_buf, big_oops_buf_sz, &text_len); 716 rc = zip_oops(text_len); 717 } 718 if (rc != 0) { 719 kmsg_dump_rewind(dumper); 720 kmsg_dump_get_buffer(dumper, false, 721 oops_data, oops_data_sz, &text_len); 722 err_type = ERR_TYPE_KERNEL_PANIC; 723 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 724 oops_hdr->report_length = cpu_to_be16(text_len); 725 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 726 } 727 728 (void) nvram_write_os_partition(&oops_log_partition, oops_buf, 729 (int) (sizeof(*oops_hdr) + text_len), err_type, 730 ++oops_count); 731 732 spin_unlock_irqrestore(&lock, flags); 733 } 734 735 static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin) 736 { 737 if (ppc_md.nvram_size == NULL) 738 return -ENODEV; 739 return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE, 740 ppc_md.nvram_size()); 741 } 742 743 744 static ssize_t dev_nvram_read(struct file *file, char __user *buf, 745 size_t count, loff_t *ppos) 746 { 747 ssize_t ret; 748 char *tmp = NULL; 749 ssize_t size; 750 751 if (!ppc_md.nvram_size) { 752 ret = -ENODEV; 753 goto out; 754 } 755 756 size = ppc_md.nvram_size(); 757 if (size < 0) { 758 ret = size; 759 goto out; 760 } 761 762 if (*ppos >= size) { 763 ret = 0; 764 goto out; 765 } 766 767 count = min_t(size_t, count, size - *ppos); 768 count = min(count, PAGE_SIZE); 769 770 tmp = kmalloc(count, GFP_KERNEL); 771 if (!tmp) { 772 ret = -ENOMEM; 773 goto out; 774 } 775 776 ret = ppc_md.nvram_read(tmp, count, ppos); 777 if (ret <= 0) 778 goto out; 779 780 if (copy_to_user(buf, tmp, ret)) 781 ret = -EFAULT; 782 783 out: 784 kfree(tmp); 785 return ret; 786 787 } 788 789 static ssize_t dev_nvram_write(struct file *file, const char __user *buf, 790 size_t count, loff_t *ppos) 791 { 792 ssize_t ret; 793 char *tmp = NULL; 794 ssize_t size; 795 796 ret = -ENODEV; 797 if (!ppc_md.nvram_size) 798 goto out; 799 800 ret = 0; 801 size = ppc_md.nvram_size(); 802 if (*ppos >= size || size < 0) 803 goto out; 804 805 count = min_t(size_t, count, size - *ppos); 806 count = min(count, PAGE_SIZE); 807 808 ret = -ENOMEM; 809 tmp = kmalloc(count, GFP_KERNEL); 810 if (!tmp) 811 goto out; 812 813 ret = -EFAULT; 814 if (copy_from_user(tmp, buf, count)) 815 goto out; 816 817 ret = ppc_md.nvram_write(tmp, count, ppos); 818 819 out: 820 kfree(tmp); 821 return ret; 822 823 } 824 825 static long dev_nvram_ioctl(struct file *file, unsigned int cmd, 826 unsigned long arg) 827 { 828 switch(cmd) { 829 #ifdef CONFIG_PPC_PMAC 830 case OBSOLETE_PMAC_NVRAM_GET_OFFSET: 831 printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n"); 832 case IOC_NVRAM_GET_OFFSET: { 833 int part, offset; 834 835 if (!machine_is(powermac)) 836 return -EINVAL; 837 if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) 838 return -EFAULT; 839 if (part < pmac_nvram_OF || part > pmac_nvram_NR) 840 return -EINVAL; 841 offset = pmac_get_partition(part); 842 if (offset < 0) 843 return offset; 844 if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) 845 return -EFAULT; 846 return 0; 847 } 848 #endif /* CONFIG_PPC_PMAC */ 849 default: 850 return -EINVAL; 851 } 852 } 853 854 const struct file_operations nvram_fops = { 855 .owner = THIS_MODULE, 856 .llseek = dev_nvram_llseek, 857 .read = dev_nvram_read, 858 .write = dev_nvram_write, 859 .unlocked_ioctl = dev_nvram_ioctl, 860 }; 861 862 static struct miscdevice nvram_dev = { 863 NVRAM_MINOR, 864 "nvram", 865 &nvram_fops 866 }; 867 868 869 #ifdef DEBUG_NVRAM 870 static void __init nvram_print_partitions(char * label) 871 { 872 struct nvram_partition * tmp_part; 873 874 printk(KERN_WARNING "--------%s---------\n", label); 875 printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n"); 876 list_for_each_entry(tmp_part, &nvram_partitions, partition) { 877 printk(KERN_WARNING "%4d \t%02x\t%02x\t%d\t%12.12s\n", 878 tmp_part->index, tmp_part->header.signature, 879 tmp_part->header.checksum, tmp_part->header.length, 880 tmp_part->header.name); 881 } 882 } 883 #endif 884 885 886 static int __init nvram_write_header(struct nvram_partition * part) 887 { 888 loff_t tmp_index; 889 int rc; 890 struct nvram_header phead; 891 892 memcpy(&phead, &part->header, NVRAM_HEADER_LEN); 893 phead.length = cpu_to_be16(phead.length); 894 895 tmp_index = part->index; 896 rc = ppc_md.nvram_write((char *)&phead, NVRAM_HEADER_LEN, &tmp_index); 897 898 return rc; 899 } 900 901 902 static unsigned char __init nvram_checksum(struct nvram_header *p) 903 { 904 unsigned int c_sum, c_sum2; 905 unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */ 906 c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5]; 907 908 /* The sum may have spilled into the 3rd byte. Fold it back. */ 909 c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff; 910 /* The sum cannot exceed 2 bytes. Fold it into a checksum */ 911 c_sum2 = (c_sum >> 8) + (c_sum << 8); 912 c_sum = ((c_sum + c_sum2) >> 8) & 0xff; 913 return c_sum; 914 } 915 916 /* 917 * Per the criteria passed via nvram_remove_partition(), should this 918 * partition be removed? 1=remove, 0=keep 919 */ 920 static int nvram_can_remove_partition(struct nvram_partition *part, 921 const char *name, int sig, const char *exceptions[]) 922 { 923 if (part->header.signature != sig) 924 return 0; 925 if (name) { 926 if (strncmp(name, part->header.name, 12)) 927 return 0; 928 } else if (exceptions) { 929 const char **except; 930 for (except = exceptions; *except; except++) { 931 if (!strncmp(*except, part->header.name, 12)) 932 return 0; 933 } 934 } 935 return 1; 936 } 937 938 /** 939 * nvram_remove_partition - Remove one or more partitions in nvram 940 * @name: name of the partition to remove, or NULL for a 941 * signature only match 942 * @sig: signature of the partition(s) to remove 943 * @exceptions: When removing all partitions with a matching signature, 944 * leave these alone. 945 */ 946 947 int __init nvram_remove_partition(const char *name, int sig, 948 const char *exceptions[]) 949 { 950 struct nvram_partition *part, *prev, *tmp; 951 int rc; 952 953 list_for_each_entry(part, &nvram_partitions, partition) { 954 if (!nvram_can_remove_partition(part, name, sig, exceptions)) 955 continue; 956 957 /* Make partition a free partition */ 958 part->header.signature = NVRAM_SIG_FREE; 959 strncpy(part->header.name, "wwwwwwwwwwww", 12); 960 part->header.checksum = nvram_checksum(&part->header); 961 rc = nvram_write_header(part); 962 if (rc <= 0) { 963 printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); 964 return rc; 965 } 966 } 967 968 /* Merge contiguous ones */ 969 prev = NULL; 970 list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) { 971 if (part->header.signature != NVRAM_SIG_FREE) { 972 prev = NULL; 973 continue; 974 } 975 if (prev) { 976 prev->header.length += part->header.length; 977 prev->header.checksum = nvram_checksum(&part->header); 978 rc = nvram_write_header(part); 979 if (rc <= 0) { 980 printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); 981 return rc; 982 } 983 list_del(&part->partition); 984 kfree(part); 985 } else 986 prev = part; 987 } 988 989 return 0; 990 } 991 992 /** 993 * nvram_create_partition - Create a partition in nvram 994 * @name: name of the partition to create 995 * @sig: signature of the partition to create 996 * @req_size: size of data to allocate in bytes 997 * @min_size: minimum acceptable size (0 means req_size) 998 * 999 * Returns a negative error code or a positive nvram index 1000 * of the beginning of the data area of the newly created 1001 * partition. If you provided a min_size smaller than req_size 1002 * you need to query for the actual size yourself after the 1003 * call using nvram_partition_get_size(). 1004 */ 1005 loff_t __init nvram_create_partition(const char *name, int sig, 1006 int req_size, int min_size) 1007 { 1008 struct nvram_partition *part; 1009 struct nvram_partition *new_part; 1010 struct nvram_partition *free_part = NULL; 1011 static char nv_init_vals[16]; 1012 loff_t tmp_index; 1013 long size = 0; 1014 int rc; 1015 1016 /* Convert sizes from bytes to blocks */ 1017 req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; 1018 min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; 1019 1020 /* If no minimum size specified, make it the same as the 1021 * requested size 1022 */ 1023 if (min_size == 0) 1024 min_size = req_size; 1025 if (min_size > req_size) 1026 return -EINVAL; 1027 1028 /* Now add one block to each for the header */ 1029 req_size += 1; 1030 min_size += 1; 1031 1032 /* Find a free partition that will give us the maximum needed size 1033 If can't find one that will give us the minimum size needed */ 1034 list_for_each_entry(part, &nvram_partitions, partition) { 1035 if (part->header.signature != NVRAM_SIG_FREE) 1036 continue; 1037 1038 if (part->header.length >= req_size) { 1039 size = req_size; 1040 free_part = part; 1041 break; 1042 } 1043 if (part->header.length > size && 1044 part->header.length >= min_size) { 1045 size = part->header.length; 1046 free_part = part; 1047 } 1048 } 1049 if (!size) 1050 return -ENOSPC; 1051 1052 /* Create our OS partition */ 1053 new_part = kmalloc(sizeof(*new_part), GFP_KERNEL); 1054 if (!new_part) { 1055 pr_err("%s: kmalloc failed\n", __func__); 1056 return -ENOMEM; 1057 } 1058 1059 new_part->index = free_part->index; 1060 new_part->header.signature = sig; 1061 new_part->header.length = size; 1062 strncpy(new_part->header.name, name, 12); 1063 new_part->header.checksum = nvram_checksum(&new_part->header); 1064 1065 rc = nvram_write_header(new_part); 1066 if (rc <= 0) { 1067 pr_err("%s: nvram_write_header failed (%d)\n", __func__, rc); 1068 kfree(new_part); 1069 return rc; 1070 } 1071 list_add_tail(&new_part->partition, &free_part->partition); 1072 1073 /* Adjust or remove the partition we stole the space from */ 1074 if (free_part->header.length > size) { 1075 free_part->index += size * NVRAM_BLOCK_LEN; 1076 free_part->header.length -= size; 1077 free_part->header.checksum = nvram_checksum(&free_part->header); 1078 rc = nvram_write_header(free_part); 1079 if (rc <= 0) { 1080 pr_err("%s: nvram_write_header failed (%d)\n", 1081 __func__, rc); 1082 return rc; 1083 } 1084 } else { 1085 list_del(&free_part->partition); 1086 kfree(free_part); 1087 } 1088 1089 /* Clear the new partition */ 1090 for (tmp_index = new_part->index + NVRAM_HEADER_LEN; 1091 tmp_index < ((size - 1) * NVRAM_BLOCK_LEN); 1092 tmp_index += NVRAM_BLOCK_LEN) { 1093 rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index); 1094 if (rc <= 0) { 1095 pr_err("%s: nvram_write failed (%d)\n", 1096 __func__, rc); 1097 return rc; 1098 } 1099 } 1100 1101 return new_part->index + NVRAM_HEADER_LEN; 1102 } 1103 1104 /** 1105 * nvram_get_partition_size - Get the data size of an nvram partition 1106 * @data_index: This is the offset of the start of the data of 1107 * the partition. The same value that is returned by 1108 * nvram_create_partition(). 1109 */ 1110 int nvram_get_partition_size(loff_t data_index) 1111 { 1112 struct nvram_partition *part; 1113 1114 list_for_each_entry(part, &nvram_partitions, partition) { 1115 if (part->index + NVRAM_HEADER_LEN == data_index) 1116 return (part->header.length - 1) * NVRAM_BLOCK_LEN; 1117 } 1118 return -1; 1119 } 1120 1121 1122 /** 1123 * nvram_find_partition - Find an nvram partition by signature and name 1124 * @name: Name of the partition or NULL for any name 1125 * @sig: Signature to test against 1126 * @out_size: if non-NULL, returns the size of the data part of the partition 1127 */ 1128 loff_t nvram_find_partition(const char *name, int sig, int *out_size) 1129 { 1130 struct nvram_partition *p; 1131 1132 list_for_each_entry(p, &nvram_partitions, partition) { 1133 if (p->header.signature == sig && 1134 (!name || !strncmp(p->header.name, name, 12))) { 1135 if (out_size) 1136 *out_size = (p->header.length - 1) * 1137 NVRAM_BLOCK_LEN; 1138 return p->index + NVRAM_HEADER_LEN; 1139 } 1140 } 1141 return 0; 1142 } 1143 1144 int __init nvram_scan_partitions(void) 1145 { 1146 loff_t cur_index = 0; 1147 struct nvram_header phead; 1148 struct nvram_partition * tmp_part; 1149 unsigned char c_sum; 1150 char * header; 1151 int total_size; 1152 int err; 1153 1154 if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) 1155 return -ENODEV; 1156 total_size = ppc_md.nvram_size(); 1157 1158 header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL); 1159 if (!header) { 1160 printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n"); 1161 return -ENOMEM; 1162 } 1163 1164 while (cur_index < total_size) { 1165 1166 err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index); 1167 if (err != NVRAM_HEADER_LEN) { 1168 printk(KERN_ERR "nvram_scan_partitions: Error parsing " 1169 "nvram partitions\n"); 1170 goto out; 1171 } 1172 1173 cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */ 1174 1175 memcpy(&phead, header, NVRAM_HEADER_LEN); 1176 1177 phead.length = be16_to_cpu(phead.length); 1178 1179 err = 0; 1180 c_sum = nvram_checksum(&phead); 1181 if (c_sum != phead.checksum) { 1182 printk(KERN_WARNING "WARNING: nvram partition checksum" 1183 " was %02x, should be %02x!\n", 1184 phead.checksum, c_sum); 1185 printk(KERN_WARNING "Terminating nvram partition scan\n"); 1186 goto out; 1187 } 1188 if (!phead.length) { 1189 printk(KERN_WARNING "WARNING: nvram corruption " 1190 "detected: 0-length partition\n"); 1191 goto out; 1192 } 1193 tmp_part = kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); 1194 err = -ENOMEM; 1195 if (!tmp_part) { 1196 printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n"); 1197 goto out; 1198 } 1199 1200 memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN); 1201 tmp_part->index = cur_index; 1202 list_add_tail(&tmp_part->partition, &nvram_partitions); 1203 1204 cur_index += phead.length * NVRAM_BLOCK_LEN; 1205 } 1206 err = 0; 1207 1208 #ifdef DEBUG_NVRAM 1209 nvram_print_partitions("NVRAM Partitions"); 1210 #endif 1211 1212 out: 1213 kfree(header); 1214 return err; 1215 } 1216 1217 static int __init nvram_init(void) 1218 { 1219 int rc; 1220 1221 BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16); 1222 1223 if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) 1224 return -ENODEV; 1225 1226 rc = misc_register(&nvram_dev); 1227 if (rc != 0) { 1228 printk(KERN_ERR "nvram_init: failed to register device\n"); 1229 return rc; 1230 } 1231 1232 return rc; 1233 } 1234 1235 static void __exit nvram_cleanup(void) 1236 { 1237 misc_deregister( &nvram_dev ); 1238 } 1239 1240 module_init(nvram_init); 1241 module_exit(nvram_cleanup); 1242 MODULE_LICENSE("GPL"); 1243