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/pstore.h> 31#include <linux/zlib.h> 32#include <asm/uaccess.h> 33#include <asm/nvram.h> 34#include <asm/rtas.h> 35#include <asm/prom.h> 36#include <asm/machdep.h> 37 38#undef DEBUG_NVRAM 39 40#define NVRAM_HEADER_LEN sizeof(struct nvram_header) 41#define NVRAM_BLOCK_LEN NVRAM_HEADER_LEN 42 43/* If change this size, then change the size of NVNAME_LEN */ 44struct nvram_header { 45 unsigned char signature; 46 unsigned char checksum; 47 unsigned short length; 48 /* Terminating null required only for names < 12 chars. */ 49 char name[12]; 50}; 51 52struct nvram_partition { 53 struct list_head partition; 54 struct nvram_header header; 55 unsigned int index; 56}; 57 58static LIST_HEAD(nvram_partitions); 59 60#ifdef CONFIG_PPC_PSERIES 61struct nvram_os_partition rtas_log_partition = { 62 .name = "ibm,rtas-log", 63 .req_size = 2079, 64 .min_size = 1055, 65 .index = -1, 66 .os_partition = true 67}; 68#endif 69 70struct nvram_os_partition oops_log_partition = { 71 .name = "lnx,oops-log", 72 .req_size = 4000, 73 .min_size = 2000, 74 .index = -1, 75 .os_partition = true 76}; 77 78static const char *nvram_os_partitions[] = { 79#ifdef CONFIG_PPC_PSERIES 80 "ibm,rtas-log", 81#endif 82 "lnx,oops-log", 83 NULL 84}; 85 86static void oops_to_nvram(struct kmsg_dumper *dumper, 87 enum kmsg_dump_reason reason); 88 89static struct kmsg_dumper nvram_kmsg_dumper = { 90 .dump = oops_to_nvram 91}; 92 93/* 94 * For capturing and compressing an oops or panic report... 95 96 * big_oops_buf[] holds the uncompressed text we're capturing. 97 * 98 * oops_buf[] holds the compressed text, preceded by a oops header. 99 * oops header has u16 holding the version of oops header (to differentiate 100 * between old and new format header) followed by u16 holding the length of 101 * the compressed* text (*Or uncompressed, if compression fails.) and u64 102 * holding the timestamp. oops_buf[] gets written to NVRAM. 103 * 104 * oops_log_info points to the header. oops_data points to the compressed text. 105 * 106 * +- oops_buf 107 * | +- oops_data 108 * v v 109 * +-----------+-----------+-----------+------------------------+ 110 * | version | length | timestamp | text | 111 * | (2 bytes) | (2 bytes) | (8 bytes) | (oops_data_sz bytes) | 112 * +-----------+-----------+-----------+------------------------+ 113 * ^ 114 * +- oops_log_info 115 * 116 * We preallocate these buffers during init to avoid kmalloc during oops/panic. 117 */ 118static size_t big_oops_buf_sz; 119static char *big_oops_buf, *oops_buf; 120static char *oops_data; 121static size_t oops_data_sz; 122 123/* Compression parameters */ 124#define COMPR_LEVEL 6 125#define WINDOW_BITS 12 126#define MEM_LEVEL 4 127static struct z_stream_s stream; 128 129#ifdef CONFIG_PSTORE 130#ifdef CONFIG_PPC_POWERNV 131static struct nvram_os_partition skiboot_partition = { 132 .name = "ibm,skiboot", 133 .index = -1, 134 .os_partition = false 135}; 136#endif 137 138#ifdef CONFIG_PPC_PSERIES 139static struct nvram_os_partition of_config_partition = { 140 .name = "of-config", 141 .index = -1, 142 .os_partition = false 143}; 144#endif 145 146static struct nvram_os_partition common_partition = { 147 .name = "common", 148 .index = -1, 149 .os_partition = false 150}; 151 152static enum pstore_type_id nvram_type_ids[] = { 153 PSTORE_TYPE_DMESG, 154 PSTORE_TYPE_PPC_COMMON, 155 -1, 156 -1, 157 -1 158}; 159static int read_type; 160#endif 161 162/* nvram_write_os_partition 163 * 164 * We need to buffer the error logs into nvram to ensure that we have 165 * the failure information to decode. If we have a severe error there 166 * is no way to guarantee that the OS or the machine is in a state to 167 * get back to user land and write the error to disk. For example if 168 * the SCSI device driver causes a Machine Check by writing to a bad 169 * IO address, there is no way of guaranteeing that the device driver 170 * is in any state that is would also be able to write the error data 171 * captured to disk, thus we buffer it in NVRAM for analysis on the 172 * next boot. 173 * 174 * In NVRAM the partition containing the error log buffer will looks like: 175 * Header (in bytes): 176 * +-----------+----------+--------+------------+------------------+ 177 * | signature | checksum | length | name | data | 178 * |0 |1 |2 3|4 15|16 length-1| 179 * +-----------+----------+--------+------------+------------------+ 180 * 181 * The 'data' section would look like (in bytes): 182 * +--------------+------------+-----------------------------------+ 183 * | event_logged | sequence # | error log | 184 * |0 3|4 7|8 error_log_size-1| 185 * +--------------+------------+-----------------------------------+ 186 * 187 * event_logged: 0 if event has not been logged to syslog, 1 if it has 188 * sequence #: The unique sequence # for each event. (until it wraps) 189 * error log: The error log from event_scan 190 */ 191int nvram_write_os_partition(struct nvram_os_partition *part, 192 char *buff, int length, 193 unsigned int err_type, 194 unsigned int error_log_cnt) 195{ 196 int rc; 197 loff_t tmp_index; 198 struct err_log_info info; 199 200 if (part->index == -1) 201 return -ESPIPE; 202 203 if (length > part->size) 204 length = part->size; 205 206 info.error_type = cpu_to_be32(err_type); 207 info.seq_num = cpu_to_be32(error_log_cnt); 208 209 tmp_index = part->index; 210 211 rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), 212 &tmp_index); 213 if (rc <= 0) { 214 pr_err("%s: Failed nvram_write (%d)\n", __func__, rc); 215 return rc; 216 } 217 218 rc = ppc_md.nvram_write(buff, length, &tmp_index); 219 if (rc <= 0) { 220 pr_err("%s: Failed nvram_write (%d)\n", __func__, rc); 221 return rc; 222 } 223 224 return 0; 225} 226 227/* nvram_read_partition 228 * 229 * Reads nvram partition for at most 'length' 230 */ 231int nvram_read_partition(struct nvram_os_partition *part, char *buff, 232 int length, unsigned int *err_type, 233 unsigned int *error_log_cnt) 234{ 235 int rc; 236 loff_t tmp_index; 237 struct err_log_info info; 238 239 if (part->index == -1) 240 return -1; 241 242 if (length > part->size) 243 length = part->size; 244 245 tmp_index = part->index; 246 247 if (part->os_partition) { 248 rc = ppc_md.nvram_read((char *)&info, 249 sizeof(struct err_log_info), 250 &tmp_index); 251 if (rc <= 0) { 252 pr_err("%s: Failed nvram_read (%d)\n", __func__, rc); 253 return rc; 254 } 255 } 256 257 rc = ppc_md.nvram_read(buff, length, &tmp_index); 258 if (rc <= 0) { 259 pr_err("%s: Failed nvram_read (%d)\n", __func__, rc); 260 return rc; 261 } 262 263 if (part->os_partition) { 264 *error_log_cnt = be32_to_cpu(info.seq_num); 265 *err_type = be32_to_cpu(info.error_type); 266 } 267 268 return 0; 269} 270 271/* nvram_init_os_partition 272 * 273 * This sets up a partition with an "OS" signature. 274 * 275 * The general strategy is the following: 276 * 1.) If a partition with the indicated name already exists... 277 * - If it's large enough, use it. 278 * - Otherwise, recycle it and keep going. 279 * 2.) Search for a free partition that is large enough. 280 * 3.) If there's not a free partition large enough, recycle any obsolete 281 * OS partitions and try again. 282 * 4.) Will first try getting a chunk that will satisfy the requested size. 283 * 5.) If a chunk of the requested size cannot be allocated, then try finding 284 * a chunk that will satisfy the minum needed. 285 * 286 * Returns 0 on success, else -1. 287 */ 288int __init nvram_init_os_partition(struct nvram_os_partition *part) 289{ 290 loff_t p; 291 int size; 292 293 /* Look for ours */ 294 p = nvram_find_partition(part->name, NVRAM_SIG_OS, &size); 295 296 /* Found one but too small, remove it */ 297 if (p && size < part->min_size) { 298 pr_info("nvram: Found too small %s partition," 299 " removing it...\n", part->name); 300 nvram_remove_partition(part->name, NVRAM_SIG_OS, NULL); 301 p = 0; 302 } 303 304 /* Create one if we didn't find */ 305 if (!p) { 306 p = nvram_create_partition(part->name, NVRAM_SIG_OS, 307 part->req_size, part->min_size); 308 if (p == -ENOSPC) { 309 pr_info("nvram: No room to create %s partition, " 310 "deleting any obsolete OS partitions...\n", 311 part->name); 312 nvram_remove_partition(NULL, NVRAM_SIG_OS, 313 nvram_os_partitions); 314 p = nvram_create_partition(part->name, NVRAM_SIG_OS, 315 part->req_size, part->min_size); 316 } 317 } 318 319 if (p <= 0) { 320 pr_err("nvram: Failed to find or create %s" 321 " partition, err %d\n", part->name, (int)p); 322 return -1; 323 } 324 325 part->index = p; 326 part->size = nvram_get_partition_size(p) - sizeof(struct err_log_info); 327 328 return 0; 329} 330 331/* Derived from logfs_compress() */ 332static int nvram_compress(const void *in, void *out, size_t inlen, 333 size_t outlen) 334{ 335 int err, ret; 336 337 ret = -EIO; 338 err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS, 339 MEM_LEVEL, Z_DEFAULT_STRATEGY); 340 if (err != Z_OK) 341 goto error; 342 343 stream.next_in = in; 344 stream.avail_in = inlen; 345 stream.total_in = 0; 346 stream.next_out = out; 347 stream.avail_out = outlen; 348 stream.total_out = 0; 349 350 err = zlib_deflate(&stream, Z_FINISH); 351 if (err != Z_STREAM_END) 352 goto error; 353 354 err = zlib_deflateEnd(&stream); 355 if (err != Z_OK) 356 goto error; 357 358 if (stream.total_out >= stream.total_in) 359 goto error; 360 361 ret = stream.total_out; 362error: 363 return ret; 364} 365 366/* Compress the text from big_oops_buf into oops_buf. */ 367static int zip_oops(size_t text_len) 368{ 369 struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; 370 int zipped_len = nvram_compress(big_oops_buf, oops_data, text_len, 371 oops_data_sz); 372 if (zipped_len < 0) { 373 pr_err("nvram: compression failed; returned %d\n", zipped_len); 374 pr_err("nvram: logging uncompressed oops/panic report\n"); 375 return -1; 376 } 377 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 378 oops_hdr->report_length = cpu_to_be16(zipped_len); 379 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 380 return 0; 381} 382 383#ifdef CONFIG_PSTORE 384static int nvram_pstore_open(struct pstore_info *psi) 385{ 386 /* Reset the iterator to start reading partitions again */ 387 read_type = -1; 388 return 0; 389} 390 391/** 392 * nvram_pstore_write - pstore write callback for nvram 393 * @type: Type of message logged 394 * @reason: reason behind dump (oops/panic) 395 * @id: identifier to indicate the write performed 396 * @part: pstore writes data to registered buffer in parts, 397 * part number will indicate the same. 398 * @count: Indicates oops count 399 * @compressed: Flag to indicate the log is compressed 400 * @size: number of bytes written to the registered buffer 401 * @psi: registered pstore_info structure 402 * 403 * Called by pstore_dump() when an oops or panic report is logged in the 404 * printk buffer. 405 * Returns 0 on successful write. 406 */ 407static int nvram_pstore_write(enum pstore_type_id type, 408 enum kmsg_dump_reason reason, 409 u64 *id, unsigned int part, int count, 410 bool compressed, size_t size, 411 struct pstore_info *psi) 412{ 413 int rc; 414 unsigned int err_type = ERR_TYPE_KERNEL_PANIC; 415 struct oops_log_info *oops_hdr = (struct oops_log_info *) oops_buf; 416 417 /* part 1 has the recent messages from printk buffer */ 418 if (part > 1 || (type != PSTORE_TYPE_DMESG)) 419 return -1; 420 421 if (clobbering_unread_rtas_event()) 422 return -1; 423 424 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 425 oops_hdr->report_length = cpu_to_be16(size); 426 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 427 428 if (compressed) 429 err_type = ERR_TYPE_KERNEL_PANIC_GZ; 430 431 rc = nvram_write_os_partition(&oops_log_partition, oops_buf, 432 (int) (sizeof(*oops_hdr) + size), err_type, count); 433 434 if (rc != 0) 435 return rc; 436 437 *id = part; 438 return 0; 439} 440 441/* 442 * Reads the oops/panic report, rtas, of-config and common partition. 443 * Returns the length of the data we read from each partition. 444 * Returns 0 if we've been called before. 445 */ 446static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type, 447 int *count, struct timespec *time, char **buf, 448 bool *compressed, struct pstore_info *psi) 449{ 450 struct oops_log_info *oops_hdr; 451 unsigned int err_type, id_no, size = 0; 452 struct nvram_os_partition *part = NULL; 453 char *buff = NULL; 454 int sig = 0; 455 loff_t p; 456 457 read_type++; 458 459 switch (nvram_type_ids[read_type]) { 460 case PSTORE_TYPE_DMESG: 461 part = &oops_log_partition; 462 *type = PSTORE_TYPE_DMESG; 463 break; 464 case PSTORE_TYPE_PPC_COMMON: 465 sig = NVRAM_SIG_SYS; 466 part = &common_partition; 467 *type = PSTORE_TYPE_PPC_COMMON; 468 *id = PSTORE_TYPE_PPC_COMMON; 469 time->tv_sec = 0; 470 time->tv_nsec = 0; 471 break; 472#ifdef CONFIG_PPC_PSERIES 473 case PSTORE_TYPE_PPC_RTAS: 474 part = &rtas_log_partition; 475 *type = PSTORE_TYPE_PPC_RTAS; 476 time->tv_sec = last_rtas_event; 477 time->tv_nsec = 0; 478 break; 479 case PSTORE_TYPE_PPC_OF: 480 sig = NVRAM_SIG_OF; 481 part = &of_config_partition; 482 *type = PSTORE_TYPE_PPC_OF; 483 *id = PSTORE_TYPE_PPC_OF; 484 time->tv_sec = 0; 485 time->tv_nsec = 0; 486 break; 487#endif 488#ifdef CONFIG_PPC_POWERNV 489 case PSTORE_TYPE_PPC_OPAL: 490 sig = NVRAM_SIG_FW; 491 part = &skiboot_partition; 492 *type = PSTORE_TYPE_PPC_OPAL; 493 *id = PSTORE_TYPE_PPC_OPAL; 494 time->tv_sec = 0; 495 time->tv_nsec = 0; 496 break; 497#endif 498 default: 499 return 0; 500 } 501 502 if (!part->os_partition) { 503 p = nvram_find_partition(part->name, sig, &size); 504 if (p <= 0) { 505 pr_err("nvram: Failed to find partition %s, " 506 "err %d\n", part->name, (int)p); 507 return 0; 508 } 509 part->index = p; 510 part->size = size; 511 } 512 513 buff = kmalloc(part->size, GFP_KERNEL); 514 515 if (!buff) 516 return -ENOMEM; 517 518 if (nvram_read_partition(part, buff, part->size, &err_type, &id_no)) { 519 kfree(buff); 520 return 0; 521 } 522 523 *count = 0; 524 525 if (part->os_partition) 526 *id = id_no; 527 528 if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) { 529 size_t length, hdr_size; 530 531 oops_hdr = (struct oops_log_info *)buff; 532 if (be16_to_cpu(oops_hdr->version) < OOPS_HDR_VERSION) { 533 /* Old format oops header had 2-byte record size */ 534 hdr_size = sizeof(u16); 535 length = be16_to_cpu(oops_hdr->version); 536 time->tv_sec = 0; 537 time->tv_nsec = 0; 538 } else { 539 hdr_size = sizeof(*oops_hdr); 540 length = be16_to_cpu(oops_hdr->report_length); 541 time->tv_sec = be64_to_cpu(oops_hdr->timestamp); 542 time->tv_nsec = 0; 543 } 544 *buf = kmemdup(buff + hdr_size, length, GFP_KERNEL); 545 if (*buf == NULL) 546 return -ENOMEM; 547 kfree(buff); 548 549 if (err_type == ERR_TYPE_KERNEL_PANIC_GZ) 550 *compressed = true; 551 else 552 *compressed = false; 553 return length; 554 } 555 556 *buf = buff; 557 return part->size; 558} 559 560static struct pstore_info nvram_pstore_info = { 561 .owner = THIS_MODULE, 562 .name = "nvram", 563 .open = nvram_pstore_open, 564 .read = nvram_pstore_read, 565 .write = nvram_pstore_write, 566}; 567 568static int nvram_pstore_init(void) 569{ 570 int rc = 0; 571 572 if (machine_is(pseries)) { 573 nvram_type_ids[2] = PSTORE_TYPE_PPC_RTAS; 574 nvram_type_ids[3] = PSTORE_TYPE_PPC_OF; 575 } else 576 nvram_type_ids[2] = PSTORE_TYPE_PPC_OPAL; 577 578 nvram_pstore_info.buf = oops_data; 579 nvram_pstore_info.bufsize = oops_data_sz; 580 581 spin_lock_init(&nvram_pstore_info.buf_lock); 582 583 rc = pstore_register(&nvram_pstore_info); 584 if (rc && (rc != -EPERM)) 585 /* Print error only when pstore.backend == nvram */ 586 pr_err("nvram: pstore_register() failed, returned %d. " 587 "Defaults to kmsg_dump\n", rc); 588 589 return rc; 590} 591#else 592static int nvram_pstore_init(void) 593{ 594 return -1; 595} 596#endif 597 598void __init nvram_init_oops_partition(int rtas_partition_exists) 599{ 600 int rc; 601 602 rc = nvram_init_os_partition(&oops_log_partition); 603 if (rc != 0) { 604#ifdef CONFIG_PPC_PSERIES 605 if (!rtas_partition_exists) { 606 pr_err("nvram: Failed to initialize oops partition!"); 607 return; 608 } 609 pr_notice("nvram: Using %s partition to log both" 610 " RTAS errors and oops/panic reports\n", 611 rtas_log_partition.name); 612 memcpy(&oops_log_partition, &rtas_log_partition, 613 sizeof(rtas_log_partition)); 614#else 615 pr_err("nvram: Failed to initialize oops partition!"); 616 return; 617#endif 618 } 619 oops_buf = kmalloc(oops_log_partition.size, GFP_KERNEL); 620 if (!oops_buf) { 621 pr_err("nvram: No memory for %s partition\n", 622 oops_log_partition.name); 623 return; 624 } 625 oops_data = oops_buf + sizeof(struct oops_log_info); 626 oops_data_sz = oops_log_partition.size - sizeof(struct oops_log_info); 627 628 rc = nvram_pstore_init(); 629 630 if (!rc) 631 return; 632 633 /* 634 * Figure compression (preceded by elimination of each line's <n> 635 * severity prefix) will reduce the oops/panic report to at most 636 * 45% of its original size. 637 */ 638 big_oops_buf_sz = (oops_data_sz * 100) / 45; 639 big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL); 640 if (big_oops_buf) { 641 stream.workspace = kmalloc(zlib_deflate_workspacesize( 642 WINDOW_BITS, MEM_LEVEL), GFP_KERNEL); 643 if (!stream.workspace) { 644 pr_err("nvram: No memory for compression workspace; " 645 "skipping compression of %s partition data\n", 646 oops_log_partition.name); 647 kfree(big_oops_buf); 648 big_oops_buf = NULL; 649 } 650 } else { 651 pr_err("No memory for uncompressed %s data; " 652 "skipping compression\n", oops_log_partition.name); 653 stream.workspace = NULL; 654 } 655 656 rc = kmsg_dump_register(&nvram_kmsg_dumper); 657 if (rc != 0) { 658 pr_err("nvram: kmsg_dump_register() failed; returned %d\n", rc); 659 kfree(oops_buf); 660 kfree(big_oops_buf); 661 kfree(stream.workspace); 662 } 663} 664 665/* 666 * This is our kmsg_dump callback, called after an oops or panic report 667 * has been written to the printk buffer. We want to capture as much 668 * of the printk buffer as possible. First, capture as much as we can 669 * that we think will compress sufficiently to fit in the lnx,oops-log 670 * partition. If that's too much, go back and capture uncompressed text. 671 */ 672static void oops_to_nvram(struct kmsg_dumper *dumper, 673 enum kmsg_dump_reason reason) 674{ 675 struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; 676 static unsigned int oops_count = 0; 677 static bool panicking = false; 678 static DEFINE_SPINLOCK(lock); 679 unsigned long flags; 680 size_t text_len; 681 unsigned int err_type = ERR_TYPE_KERNEL_PANIC_GZ; 682 int rc = -1; 683 684 switch (reason) { 685 case KMSG_DUMP_RESTART: 686 case KMSG_DUMP_HALT: 687 case KMSG_DUMP_POWEROFF: 688 /* These are almost always orderly shutdowns. */ 689 return; 690 case KMSG_DUMP_OOPS: 691 break; 692 case KMSG_DUMP_PANIC: 693 panicking = true; 694 break; 695 case KMSG_DUMP_EMERG: 696 if (panicking) 697 /* Panic report already captured. */ 698 return; 699 break; 700 default: 701 pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n", 702 __func__, (int) reason); 703 return; 704 } 705 706 if (clobbering_unread_rtas_event()) 707 return; 708 709 if (!spin_trylock_irqsave(&lock, flags)) 710 return; 711 712 if (big_oops_buf) { 713 kmsg_dump_get_buffer(dumper, false, 714 big_oops_buf, big_oops_buf_sz, &text_len); 715 rc = zip_oops(text_len); 716 } 717 if (rc != 0) { 718 kmsg_dump_rewind(dumper); 719 kmsg_dump_get_buffer(dumper, false, 720 oops_data, oops_data_sz, &text_len); 721 err_type = ERR_TYPE_KERNEL_PANIC; 722 oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); 723 oops_hdr->report_length = cpu_to_be16(text_len); 724 oops_hdr->timestamp = cpu_to_be64(ktime_get_real_seconds()); 725 } 726 727 (void) nvram_write_os_partition(&oops_log_partition, oops_buf, 728 (int) (sizeof(*oops_hdr) + text_len), err_type, 729 ++oops_count); 730 731 spin_unlock_irqrestore(&lock, flags); 732} 733 734static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin) 735{ 736 int size; 737 738 if (ppc_md.nvram_size == NULL) 739 return -ENODEV; 740 size = ppc_md.nvram_size(); 741 742 switch (origin) { 743 case 1: 744 offset += file->f_pos; 745 break; 746 case 2: 747 offset += size; 748 break; 749 } 750 if (offset < 0) 751 return -EINVAL; 752 file->f_pos = offset; 753 return file->f_pos; 754} 755 756 757static ssize_t dev_nvram_read(struct file *file, char __user *buf, 758 size_t count, loff_t *ppos) 759{ 760 ssize_t ret; 761 char *tmp = NULL; 762 ssize_t size; 763 764 if (!ppc_md.nvram_size) { 765 ret = -ENODEV; 766 goto out; 767 } 768 769 size = ppc_md.nvram_size(); 770 if (size < 0) { 771 ret = size; 772 goto out; 773 } 774 775 if (*ppos >= size) { 776 ret = 0; 777 goto out; 778 } 779 780 count = min_t(size_t, count, size - *ppos); 781 count = min(count, PAGE_SIZE); 782 783 tmp = kmalloc(count, GFP_KERNEL); 784 if (!tmp) { 785 ret = -ENOMEM; 786 goto out; 787 } 788 789 ret = ppc_md.nvram_read(tmp, count, ppos); 790 if (ret <= 0) 791 goto out; 792 793 if (copy_to_user(buf, tmp, ret)) 794 ret = -EFAULT; 795 796out: 797 kfree(tmp); 798 return ret; 799 800} 801 802static ssize_t dev_nvram_write(struct file *file, const char __user *buf, 803 size_t count, loff_t *ppos) 804{ 805 ssize_t ret; 806 char *tmp = NULL; 807 ssize_t size; 808 809 ret = -ENODEV; 810 if (!ppc_md.nvram_size) 811 goto out; 812 813 ret = 0; 814 size = ppc_md.nvram_size(); 815 if (*ppos >= size || size < 0) 816 goto out; 817 818 count = min_t(size_t, count, size - *ppos); 819 count = min(count, PAGE_SIZE); 820 821 ret = -ENOMEM; 822 tmp = kmalloc(count, GFP_KERNEL); 823 if (!tmp) 824 goto out; 825 826 ret = -EFAULT; 827 if (copy_from_user(tmp, buf, count)) 828 goto out; 829 830 ret = ppc_md.nvram_write(tmp, count, ppos); 831 832out: 833 kfree(tmp); 834 return ret; 835 836} 837 838static long dev_nvram_ioctl(struct file *file, unsigned int cmd, 839 unsigned long arg) 840{ 841 switch(cmd) { 842#ifdef CONFIG_PPC_PMAC 843 case OBSOLETE_PMAC_NVRAM_GET_OFFSET: 844 printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n"); 845 case IOC_NVRAM_GET_OFFSET: { 846 int part, offset; 847 848 if (!machine_is(powermac)) 849 return -EINVAL; 850 if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) 851 return -EFAULT; 852 if (part < pmac_nvram_OF || part > pmac_nvram_NR) 853 return -EINVAL; 854 offset = pmac_get_partition(part); 855 if (offset < 0) 856 return offset; 857 if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) 858 return -EFAULT; 859 return 0; 860 } 861#endif /* CONFIG_PPC_PMAC */ 862 default: 863 return -EINVAL; 864 } 865} 866 867const struct file_operations nvram_fops = { 868 .owner = THIS_MODULE, 869 .llseek = dev_nvram_llseek, 870 .read = dev_nvram_read, 871 .write = dev_nvram_write, 872 .unlocked_ioctl = dev_nvram_ioctl, 873}; 874 875static struct miscdevice nvram_dev = { 876 NVRAM_MINOR, 877 "nvram", 878 &nvram_fops 879}; 880 881 882#ifdef DEBUG_NVRAM 883static void __init nvram_print_partitions(char * label) 884{ 885 struct nvram_partition * tmp_part; 886 887 printk(KERN_WARNING "--------%s---------\n", label); 888 printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n"); 889 list_for_each_entry(tmp_part, &nvram_partitions, partition) { 890 printk(KERN_WARNING "%4d \t%02x\t%02x\t%d\t%12.12s\n", 891 tmp_part->index, tmp_part->header.signature, 892 tmp_part->header.checksum, tmp_part->header.length, 893 tmp_part->header.name); 894 } 895} 896#endif 897 898 899static int __init nvram_write_header(struct nvram_partition * part) 900{ 901 loff_t tmp_index; 902 int rc; 903 struct nvram_header phead; 904 905 memcpy(&phead, &part->header, NVRAM_HEADER_LEN); 906 phead.length = cpu_to_be16(phead.length); 907 908 tmp_index = part->index; 909 rc = ppc_md.nvram_write((char *)&phead, NVRAM_HEADER_LEN, &tmp_index); 910 911 return rc; 912} 913 914 915static unsigned char __init nvram_checksum(struct nvram_header *p) 916{ 917 unsigned int c_sum, c_sum2; 918 unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */ 919 c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5]; 920 921 /* The sum may have spilled into the 3rd byte. Fold it back. */ 922 c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff; 923 /* The sum cannot exceed 2 bytes. Fold it into a checksum */ 924 c_sum2 = (c_sum >> 8) + (c_sum << 8); 925 c_sum = ((c_sum + c_sum2) >> 8) & 0xff; 926 return c_sum; 927} 928 929/* 930 * Per the criteria passed via nvram_remove_partition(), should this 931 * partition be removed? 1=remove, 0=keep 932 */ 933static int nvram_can_remove_partition(struct nvram_partition *part, 934 const char *name, int sig, const char *exceptions[]) 935{ 936 if (part->header.signature != sig) 937 return 0; 938 if (name) { 939 if (strncmp(name, part->header.name, 12)) 940 return 0; 941 } else if (exceptions) { 942 const char **except; 943 for (except = exceptions; *except; except++) { 944 if (!strncmp(*except, part->header.name, 12)) 945 return 0; 946 } 947 } 948 return 1; 949} 950 951/** 952 * nvram_remove_partition - Remove one or more partitions in nvram 953 * @name: name of the partition to remove, or NULL for a 954 * signature only match 955 * @sig: signature of the partition(s) to remove 956 * @exceptions: When removing all partitions with a matching signature, 957 * leave these alone. 958 */ 959 960int __init nvram_remove_partition(const char *name, int sig, 961 const char *exceptions[]) 962{ 963 struct nvram_partition *part, *prev, *tmp; 964 int rc; 965 966 list_for_each_entry(part, &nvram_partitions, partition) { 967 if (!nvram_can_remove_partition(part, name, sig, exceptions)) 968 continue; 969 970 /* Make partition a free partition */ 971 part->header.signature = NVRAM_SIG_FREE; 972 strncpy(part->header.name, "wwwwwwwwwwww", 12); 973 part->header.checksum = nvram_checksum(&part->header); 974 rc = nvram_write_header(part); 975 if (rc <= 0) { 976 printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); 977 return rc; 978 } 979 } 980 981 /* Merge contiguous ones */ 982 prev = NULL; 983 list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) { 984 if (part->header.signature != NVRAM_SIG_FREE) { 985 prev = NULL; 986 continue; 987 } 988 if (prev) { 989 prev->header.length += part->header.length; 990 prev->header.checksum = nvram_checksum(&part->header); 991 rc = nvram_write_header(part); 992 if (rc <= 0) { 993 printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); 994 return rc; 995 } 996 list_del(&part->partition); 997 kfree(part); 998 } else 999 prev = part; 1000 } 1001 1002 return 0; 1003} 1004 1005/** 1006 * nvram_create_partition - Create a partition in nvram 1007 * @name: name of the partition to create 1008 * @sig: signature of the partition to create 1009 * @req_size: size of data to allocate in bytes 1010 * @min_size: minimum acceptable size (0 means req_size) 1011 * 1012 * Returns a negative error code or a positive nvram index 1013 * of the beginning of the data area of the newly created 1014 * partition. If you provided a min_size smaller than req_size 1015 * you need to query for the actual size yourself after the 1016 * call using nvram_partition_get_size(). 1017 */ 1018loff_t __init nvram_create_partition(const char *name, int sig, 1019 int req_size, int min_size) 1020{ 1021 struct nvram_partition *part; 1022 struct nvram_partition *new_part; 1023 struct nvram_partition *free_part = NULL; 1024 static char nv_init_vals[16]; 1025 loff_t tmp_index; 1026 long size = 0; 1027 int rc; 1028 1029 /* Convert sizes from bytes to blocks */ 1030 req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; 1031 min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; 1032 1033 /* If no minimum size specified, make it the same as the 1034 * requested size 1035 */ 1036 if (min_size == 0) 1037 min_size = req_size; 1038 if (min_size > req_size) 1039 return -EINVAL; 1040 1041 /* Now add one block to each for the header */ 1042 req_size += 1; 1043 min_size += 1; 1044 1045 /* Find a free partition that will give us the maximum needed size 1046 If can't find one that will give us the minimum size needed */ 1047 list_for_each_entry(part, &nvram_partitions, partition) { 1048 if (part->header.signature != NVRAM_SIG_FREE) 1049 continue; 1050 1051 if (part->header.length >= req_size) { 1052 size = req_size; 1053 free_part = part; 1054 break; 1055 } 1056 if (part->header.length > size && 1057 part->header.length >= min_size) { 1058 size = part->header.length; 1059 free_part = part; 1060 } 1061 } 1062 if (!size) 1063 return -ENOSPC; 1064 1065 /* Create our OS partition */ 1066 new_part = kmalloc(sizeof(*new_part), GFP_KERNEL); 1067 if (!new_part) { 1068 pr_err("%s: kmalloc failed\n", __func__); 1069 return -ENOMEM; 1070 } 1071 1072 new_part->index = free_part->index; 1073 new_part->header.signature = sig; 1074 new_part->header.length = size; 1075 strncpy(new_part->header.name, name, 12); 1076 new_part->header.checksum = nvram_checksum(&new_part->header); 1077 1078 rc = nvram_write_header(new_part); 1079 if (rc <= 0) { 1080 pr_err("%s: nvram_write_header failed (%d)\n", __func__, rc); 1081 kfree(new_part); 1082 return rc; 1083 } 1084 list_add_tail(&new_part->partition, &free_part->partition); 1085 1086 /* Adjust or remove the partition we stole the space from */ 1087 if (free_part->header.length > size) { 1088 free_part->index += size * NVRAM_BLOCK_LEN; 1089 free_part->header.length -= size; 1090 free_part->header.checksum = nvram_checksum(&free_part->header); 1091 rc = nvram_write_header(free_part); 1092 if (rc <= 0) { 1093 pr_err("%s: nvram_write_header failed (%d)\n", 1094 __func__, rc); 1095 return rc; 1096 } 1097 } else { 1098 list_del(&free_part->partition); 1099 kfree(free_part); 1100 } 1101 1102 /* Clear the new partition */ 1103 for (tmp_index = new_part->index + NVRAM_HEADER_LEN; 1104 tmp_index < ((size - 1) * NVRAM_BLOCK_LEN); 1105 tmp_index += NVRAM_BLOCK_LEN) { 1106 rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index); 1107 if (rc <= 0) { 1108 pr_err("%s: nvram_write failed (%d)\n", 1109 __func__, rc); 1110 return rc; 1111 } 1112 } 1113 1114 return new_part->index + NVRAM_HEADER_LEN; 1115} 1116 1117/** 1118 * nvram_get_partition_size - Get the data size of an nvram partition 1119 * @data_index: This is the offset of the start of the data of 1120 * the partition. The same value that is returned by 1121 * nvram_create_partition(). 1122 */ 1123int nvram_get_partition_size(loff_t data_index) 1124{ 1125 struct nvram_partition *part; 1126 1127 list_for_each_entry(part, &nvram_partitions, partition) { 1128 if (part->index + NVRAM_HEADER_LEN == data_index) 1129 return (part->header.length - 1) * NVRAM_BLOCK_LEN; 1130 } 1131 return -1; 1132} 1133 1134 1135/** 1136 * nvram_find_partition - Find an nvram partition by signature and name 1137 * @name: Name of the partition or NULL for any name 1138 * @sig: Signature to test against 1139 * @out_size: if non-NULL, returns the size of the data part of the partition 1140 */ 1141loff_t nvram_find_partition(const char *name, int sig, int *out_size) 1142{ 1143 struct nvram_partition *p; 1144 1145 list_for_each_entry(p, &nvram_partitions, partition) { 1146 if (p->header.signature == sig && 1147 (!name || !strncmp(p->header.name, name, 12))) { 1148 if (out_size) 1149 *out_size = (p->header.length - 1) * 1150 NVRAM_BLOCK_LEN; 1151 return p->index + NVRAM_HEADER_LEN; 1152 } 1153 } 1154 return 0; 1155} 1156 1157int __init nvram_scan_partitions(void) 1158{ 1159 loff_t cur_index = 0; 1160 struct nvram_header phead; 1161 struct nvram_partition * tmp_part; 1162 unsigned char c_sum; 1163 char * header; 1164 int total_size; 1165 int err; 1166 1167 if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) 1168 return -ENODEV; 1169 total_size = ppc_md.nvram_size(); 1170 1171 header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL); 1172 if (!header) { 1173 printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n"); 1174 return -ENOMEM; 1175 } 1176 1177 while (cur_index < total_size) { 1178 1179 err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index); 1180 if (err != NVRAM_HEADER_LEN) { 1181 printk(KERN_ERR "nvram_scan_partitions: Error parsing " 1182 "nvram partitions\n"); 1183 goto out; 1184 } 1185 1186 cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */ 1187 1188 memcpy(&phead, header, NVRAM_HEADER_LEN); 1189 1190 phead.length = be16_to_cpu(phead.length); 1191 1192 err = 0; 1193 c_sum = nvram_checksum(&phead); 1194 if (c_sum != phead.checksum) { 1195 printk(KERN_WARNING "WARNING: nvram partition checksum" 1196 " was %02x, should be %02x!\n", 1197 phead.checksum, c_sum); 1198 printk(KERN_WARNING "Terminating nvram partition scan\n"); 1199 goto out; 1200 } 1201 if (!phead.length) { 1202 printk(KERN_WARNING "WARNING: nvram corruption " 1203 "detected: 0-length partition\n"); 1204 goto out; 1205 } 1206 tmp_part = kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); 1207 err = -ENOMEM; 1208 if (!tmp_part) { 1209 printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n"); 1210 goto out; 1211 } 1212 1213 memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN); 1214 tmp_part->index = cur_index; 1215 list_add_tail(&tmp_part->partition, &nvram_partitions); 1216 1217 cur_index += phead.length * NVRAM_BLOCK_LEN; 1218 } 1219 err = 0; 1220 1221#ifdef DEBUG_NVRAM 1222 nvram_print_partitions("NVRAM Partitions"); 1223#endif 1224 1225 out: 1226 kfree(header); 1227 return err; 1228} 1229 1230static int __init nvram_init(void) 1231{ 1232 int rc; 1233 1234 BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16); 1235 1236 if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) 1237 return -ENODEV; 1238 1239 rc = misc_register(&nvram_dev); 1240 if (rc != 0) { 1241 printk(KERN_ERR "nvram_init: failed to register device\n"); 1242 return rc; 1243 } 1244 1245 return rc; 1246} 1247 1248static void __exit nvram_cleanup(void) 1249{ 1250 misc_deregister( &nvram_dev ); 1251} 1252 1253module_init(nvram_init); 1254module_exit(nvram_cleanup); 1255MODULE_LICENSE("GPL"); 1256