| 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 2 | /* |
| 3 | * Core registration and callback routines for MTD |
| 4 | * drivers and users. |
| 5 | * |
| 6 | * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> |
| 7 | * Copyright © 2006 Red Hat UK Limited |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/ptrace.h> |
| 13 | #include <linux/seq_file.h> |
| 14 | #include <linux/string.h> |
| 15 | #include <linux/timer.h> |
| 16 | #include <linux/major.h> |
| 17 | #include <linux/fs.h> |
| 18 | #include <linux/err.h> |
| 19 | #include <linux/ioctl.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/of.h> |
| 22 | #include <linux/proc_fs.h> |
| 23 | #include <linux/idr.h> |
| 24 | #include <linux/backing-dev.h> |
| 25 | #include <linux/gfp.h> |
| 26 | #include <linux/random.h> |
| 27 | #include <linux/slab.h> |
| 28 | #include <linux/reboot.h> |
| 29 | #include <linux/leds.h> |
| 30 | #include <linux/debugfs.h> |
| 31 | #include <linux/nvmem-provider.h> |
| 32 | #include <linux/root_dev.h> |
| 33 | |
| 34 | #include <linux/mtd/mtd.h> |
| 35 | #include <linux/mtd/partitions.h> |
| 36 | |
| 37 | #include "mtdcore.h" |
| 38 | |
| 39 | struct backing_dev_info *mtd_bdi; |
| 40 | |
| 41 | #ifdef CONFIG_PM_SLEEP |
| 42 | |
| 43 | static int mtd_cls_suspend(struct device *dev) |
| 44 | { |
| 45 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 46 | |
| 47 | return mtd ? mtd_suspend(mtd) : 0; |
| 48 | } |
| 49 | |
| 50 | static int mtd_cls_resume(struct device *dev) |
| 51 | { |
| 52 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 53 | |
| 54 | if (mtd) |
| 55 | mtd_resume(mtd); |
| 56 | return 0; |
| 57 | } |
| 58 | |
| 59 | static SIMPLE_DEV_PM_OPS(mtd_cls_pm_ops, mtd_cls_suspend, mtd_cls_resume); |
| 60 | #define MTD_CLS_PM_OPS (&mtd_cls_pm_ops) |
| 61 | #else |
| 62 | #define MTD_CLS_PM_OPS NULL |
| 63 | #endif |
| 64 | |
| 65 | static struct class mtd_class = { |
| 66 | .name = "mtd", |
| 67 | .pm = MTD_CLS_PM_OPS, |
| 68 | }; |
| 69 | |
| 70 | static DEFINE_IDR(mtd_idr); |
| 71 | |
| 72 | /* These are exported solely for the purpose of mtd_blkdevs.c. You |
| 73 | should not use them for _anything_ else */ |
| 74 | DEFINE_MUTEX(mtd_table_mutex); |
| 75 | EXPORT_SYMBOL_GPL(mtd_table_mutex); |
| 76 | |
| 77 | struct mtd_info *__mtd_next_device(int i) |
| 78 | { |
| 79 | return idr_get_next(&mtd_idr, &i); |
| 80 | } |
| 81 | EXPORT_SYMBOL_GPL(__mtd_next_device); |
| 82 | |
| 83 | static LIST_HEAD(mtd_notifiers); |
| 84 | |
| 85 | |
| 86 | #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2) |
| 87 | |
| 88 | /* REVISIT once MTD uses the driver model better, whoever allocates |
| 89 | * the mtd_info will probably want to use the release() hook... |
| 90 | */ |
| 91 | static void mtd_release(struct device *dev) |
| 92 | { |
| 93 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 94 | dev_t index = MTD_DEVT(mtd->index); |
| 95 | |
| 96 | idr_remove(&mtd_idr, mtd->index); |
| 97 | of_node_put(mtd_get_of_node(mtd)); |
| 98 | |
| 99 | if (mtd_is_partition(mtd)) |
| 100 | release_mtd_partition(mtd); |
| 101 | |
| 102 | /* remove /dev/mtdXro node */ |
| 103 | device_destroy(&mtd_class, index + 1); |
| 104 | } |
| 105 | |
| 106 | static void mtd_device_release(struct kref *kref) |
| 107 | { |
| 108 | struct mtd_info *mtd = container_of(kref, struct mtd_info, refcnt); |
| 109 | bool is_partition = mtd_is_partition(mtd); |
| 110 | |
| 111 | debugfs_remove_recursive(mtd->dbg.dfs_dir); |
| 112 | |
| 113 | /* Try to remove the NVMEM provider */ |
| 114 | nvmem_unregister(mtd->nvmem); |
| 115 | |
| 116 | device_unregister(&mtd->dev); |
| 117 | |
| 118 | /* |
| 119 | * Clear dev so mtd can be safely re-registered later if desired. |
| 120 | * Should not be done for partition, |
| 121 | * as it was already destroyed in device_unregister(). |
| 122 | */ |
| 123 | if (!is_partition) |
| 124 | memset(&mtd->dev, 0, sizeof(mtd->dev)); |
| 125 | |
| 126 | module_put(THIS_MODULE); |
| 127 | } |
| 128 | |
| 129 | #define MTD_DEVICE_ATTR_RO(name) \ |
| 130 | static DEVICE_ATTR(name, 0444, mtd_##name##_show, NULL) |
| 131 | |
| 132 | #define MTD_DEVICE_ATTR_RW(name) \ |
| 133 | static DEVICE_ATTR(name, 0644, mtd_##name##_show, mtd_##name##_store) |
| 134 | |
| 135 | static ssize_t mtd_type_show(struct device *dev, |
| 136 | struct device_attribute *attr, char *buf) |
| 137 | { |
| 138 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 139 | char *type; |
| 140 | |
| 141 | switch (mtd->type) { |
| 142 | case MTD_ABSENT: |
| 143 | type = "absent"; |
| 144 | break; |
| 145 | case MTD_RAM: |
| 146 | type = "ram"; |
| 147 | break; |
| 148 | case MTD_ROM: |
| 149 | type = "rom"; |
| 150 | break; |
| 151 | case MTD_NORFLASH: |
| 152 | type = "nor"; |
| 153 | break; |
| 154 | case MTD_NANDFLASH: |
| 155 | type = "nand"; |
| 156 | break; |
| 157 | case MTD_DATAFLASH: |
| 158 | type = "dataflash"; |
| 159 | break; |
| 160 | case MTD_UBIVOLUME: |
| 161 | type = "ubi"; |
| 162 | break; |
| 163 | case MTD_MLCNANDFLASH: |
| 164 | type = "mlc-nand"; |
| 165 | break; |
| 166 | default: |
| 167 | type = "unknown"; |
| 168 | } |
| 169 | |
| 170 | return sysfs_emit(buf, "%s\n", type); |
| 171 | } |
| 172 | MTD_DEVICE_ATTR_RO(type); |
| 173 | |
| 174 | static ssize_t mtd_flags_show(struct device *dev, |
| 175 | struct device_attribute *attr, char *buf) |
| 176 | { |
| 177 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 178 | |
| 179 | return sysfs_emit(buf, "0x%lx\n", (unsigned long)mtd->flags); |
| 180 | } |
| 181 | MTD_DEVICE_ATTR_RO(flags); |
| 182 | |
| 183 | static ssize_t mtd_size_show(struct device *dev, |
| 184 | struct device_attribute *attr, char *buf) |
| 185 | { |
| 186 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 187 | |
| 188 | return sysfs_emit(buf, "%llu\n", (unsigned long long)mtd->size); |
| 189 | } |
| 190 | MTD_DEVICE_ATTR_RO(size); |
| 191 | |
| 192 | static ssize_t mtd_erasesize_show(struct device *dev, |
| 193 | struct device_attribute *attr, char *buf) |
| 194 | { |
| 195 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 196 | |
| 197 | return sysfs_emit(buf, "%lu\n", (unsigned long)mtd->erasesize); |
| 198 | } |
| 199 | MTD_DEVICE_ATTR_RO(erasesize); |
| 200 | |
| 201 | static ssize_t mtd_writesize_show(struct device *dev, |
| 202 | struct device_attribute *attr, char *buf) |
| 203 | { |
| 204 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 205 | |
| 206 | return sysfs_emit(buf, "%lu\n", (unsigned long)mtd->writesize); |
| 207 | } |
| 208 | MTD_DEVICE_ATTR_RO(writesize); |
| 209 | |
| 210 | static ssize_t mtd_subpagesize_show(struct device *dev, |
| 211 | struct device_attribute *attr, char *buf) |
| 212 | { |
| 213 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 214 | unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft; |
| 215 | |
| 216 | return sysfs_emit(buf, "%u\n", subpagesize); |
| 217 | } |
| 218 | MTD_DEVICE_ATTR_RO(subpagesize); |
| 219 | |
| 220 | static ssize_t mtd_oobsize_show(struct device *dev, |
| 221 | struct device_attribute *attr, char *buf) |
| 222 | { |
| 223 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 224 | |
| 225 | return sysfs_emit(buf, "%lu\n", (unsigned long)mtd->oobsize); |
| 226 | } |
| 227 | MTD_DEVICE_ATTR_RO(oobsize); |
| 228 | |
| 229 | static ssize_t mtd_oobavail_show(struct device *dev, |
| 230 | struct device_attribute *attr, char *buf) |
| 231 | { |
| 232 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 233 | |
| 234 | return sysfs_emit(buf, "%u\n", mtd->oobavail); |
| 235 | } |
| 236 | MTD_DEVICE_ATTR_RO(oobavail); |
| 237 | |
| 238 | static ssize_t mtd_numeraseregions_show(struct device *dev, |
| 239 | struct device_attribute *attr, char *buf) |
| 240 | { |
| 241 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 242 | |
| 243 | return sysfs_emit(buf, "%u\n", mtd->numeraseregions); |
| 244 | } |
| 245 | MTD_DEVICE_ATTR_RO(numeraseregions); |
| 246 | |
| 247 | static ssize_t mtd_name_show(struct device *dev, |
| 248 | struct device_attribute *attr, char *buf) |
| 249 | { |
| 250 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 251 | |
| 252 | return sysfs_emit(buf, "%s\n", mtd->name); |
| 253 | } |
| 254 | MTD_DEVICE_ATTR_RO(name); |
| 255 | |
| 256 | static ssize_t mtd_ecc_strength_show(struct device *dev, |
| 257 | struct device_attribute *attr, char *buf) |
| 258 | { |
| 259 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 260 | |
| 261 | return sysfs_emit(buf, "%u\n", mtd->ecc_strength); |
| 262 | } |
| 263 | MTD_DEVICE_ATTR_RO(ecc_strength); |
| 264 | |
| 265 | static ssize_t mtd_bitflip_threshold_show(struct device *dev, |
| 266 | struct device_attribute *attr, |
| 267 | char *buf) |
| 268 | { |
| 269 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 270 | |
| 271 | return sysfs_emit(buf, "%u\n", mtd->bitflip_threshold); |
| 272 | } |
| 273 | |
| 274 | static ssize_t mtd_bitflip_threshold_store(struct device *dev, |
| 275 | struct device_attribute *attr, |
| 276 | const char *buf, size_t count) |
| 277 | { |
| 278 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 279 | unsigned int bitflip_threshold; |
| 280 | int retval; |
| 281 | |
| 282 | retval = kstrtouint(buf, 0, &bitflip_threshold); |
| 283 | if (retval) |
| 284 | return retval; |
| 285 | |
| 286 | mtd->bitflip_threshold = bitflip_threshold; |
| 287 | return count; |
| 288 | } |
| 289 | MTD_DEVICE_ATTR_RW(bitflip_threshold); |
| 290 | |
| 291 | static ssize_t mtd_ecc_step_size_show(struct device *dev, |
| 292 | struct device_attribute *attr, char *buf) |
| 293 | { |
| 294 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 295 | |
| 296 | return sysfs_emit(buf, "%u\n", mtd->ecc_step_size); |
| 297 | |
| 298 | } |
| 299 | MTD_DEVICE_ATTR_RO(ecc_step_size); |
| 300 | |
| 301 | static ssize_t mtd_corrected_bits_show(struct device *dev, |
| 302 | struct device_attribute *attr, char *buf) |
| 303 | { |
| 304 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 305 | struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats; |
| 306 | |
| 307 | return sysfs_emit(buf, "%u\n", ecc_stats->corrected); |
| 308 | } |
| 309 | MTD_DEVICE_ATTR_RO(corrected_bits); /* ecc stats corrected */ |
| 310 | |
| 311 | static ssize_t mtd_ecc_failures_show(struct device *dev, |
| 312 | struct device_attribute *attr, char *buf) |
| 313 | { |
| 314 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 315 | struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats; |
| 316 | |
| 317 | return sysfs_emit(buf, "%u\n", ecc_stats->failed); |
| 318 | } |
| 319 | MTD_DEVICE_ATTR_RO(ecc_failures); /* ecc stats errors */ |
| 320 | |
| 321 | static ssize_t mtd_bad_blocks_show(struct device *dev, |
| 322 | struct device_attribute *attr, char *buf) |
| 323 | { |
| 324 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 325 | struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats; |
| 326 | |
| 327 | return sysfs_emit(buf, "%u\n", ecc_stats->badblocks); |
| 328 | } |
| 329 | MTD_DEVICE_ATTR_RO(bad_blocks); |
| 330 | |
| 331 | static ssize_t mtd_bbt_blocks_show(struct device *dev, |
| 332 | struct device_attribute *attr, char *buf) |
| 333 | { |
| 334 | struct mtd_info *mtd = dev_get_drvdata(dev); |
| 335 | struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats; |
| 336 | |
| 337 | return sysfs_emit(buf, "%u\n", ecc_stats->bbtblocks); |
| 338 | } |
| 339 | MTD_DEVICE_ATTR_RO(bbt_blocks); |
| 340 | |
| 341 | static struct attribute *mtd_attrs[] = { |
| 342 | &dev_attr_type.attr, |
| 343 | &dev_attr_flags.attr, |
| 344 | &dev_attr_size.attr, |
| 345 | &dev_attr_erasesize.attr, |
| 346 | &dev_attr_writesize.attr, |
| 347 | &dev_attr_subpagesize.attr, |
| 348 | &dev_attr_oobsize.attr, |
| 349 | &dev_attr_oobavail.attr, |
| 350 | &dev_attr_numeraseregions.attr, |
| 351 | &dev_attr_name.attr, |
| 352 | &dev_attr_ecc_strength.attr, |
| 353 | &dev_attr_ecc_step_size.attr, |
| 354 | &dev_attr_corrected_bits.attr, |
| 355 | &dev_attr_ecc_failures.attr, |
| 356 | &dev_attr_bad_blocks.attr, |
| 357 | &dev_attr_bbt_blocks.attr, |
| 358 | &dev_attr_bitflip_threshold.attr, |
| 359 | NULL, |
| 360 | }; |
| 361 | ATTRIBUTE_GROUPS(mtd); |
| 362 | |
| 363 | static const struct device_type mtd_devtype = { |
| 364 | .name = "mtd", |
| 365 | .groups = mtd_groups, |
| 366 | .release = mtd_release, |
| 367 | }; |
| 368 | |
| 369 | static bool mtd_expert_analysis_mode; |
| 370 | |
| 371 | #ifdef CONFIG_DEBUG_FS |
| 372 | bool mtd_check_expert_analysis_mode(void) |
| 373 | { |
| 374 | const char *mtd_expert_analysis_warning = |
| 375 | "Bad block checks have been entirely disabled.\n" |
| 376 | "This is only reserved for post-mortem forensics and debug purposes.\n" |
| 377 | "Never enable this mode if you do not know what you are doing!\n"; |
| 378 | |
| 379 | return WARN_ONCE(mtd_expert_analysis_mode, mtd_expert_analysis_warning); |
| 380 | } |
| 381 | EXPORT_SYMBOL_GPL(mtd_check_expert_analysis_mode); |
| 382 | #endif |
| 383 | |
| 384 | static struct dentry *dfs_dir_mtd; |
| 385 | |
| 386 | static void mtd_debugfs_populate(struct mtd_info *mtd) |
| 387 | { |
| 388 | struct device *dev = &mtd->dev; |
| 389 | |
| 390 | if (IS_ERR_OR_NULL(dfs_dir_mtd)) |
| 391 | return; |
| 392 | |
| 393 | mtd->dbg.dfs_dir = debugfs_create_dir(dev_name(dev), dfs_dir_mtd); |
| 394 | } |
| 395 | |
| 396 | #ifndef CONFIG_MMU |
| 397 | unsigned mtd_mmap_capabilities(struct mtd_info *mtd) |
| 398 | { |
| 399 | switch (mtd->type) { |
| 400 | case MTD_RAM: |
| 401 | return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC | |
| 402 | NOMMU_MAP_READ | NOMMU_MAP_WRITE; |
| 403 | case MTD_ROM: |
| 404 | return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC | |
| 405 | NOMMU_MAP_READ; |
| 406 | default: |
| 407 | return NOMMU_MAP_COPY; |
| 408 | } |
| 409 | } |
| 410 | EXPORT_SYMBOL_GPL(mtd_mmap_capabilities); |
| 411 | #endif |
| 412 | |
| 413 | static int mtd_reboot_notifier(struct notifier_block *n, unsigned long state, |
| 414 | void *cmd) |
| 415 | { |
| 416 | struct mtd_info *mtd; |
| 417 | |
| 418 | mtd = container_of(n, struct mtd_info, reboot_notifier); |
| 419 | mtd->_reboot(mtd); |
| 420 | |
| 421 | return NOTIFY_DONE; |
| 422 | } |
| 423 | |
| 424 | /** |
| 425 | * mtd_wunit_to_pairing_info - get pairing information of a wunit |
| 426 | * @mtd: pointer to new MTD device info structure |
| 427 | * @wunit: write unit we are interested in |
| 428 | * @info: returned pairing information |
| 429 | * |
| 430 | * Retrieve pairing information associated to the wunit. |
| 431 | * This is mainly useful when dealing with MLC/TLC NANDs where pages can be |
| 432 | * paired together, and where programming a page may influence the page it is |
| 433 | * paired with. |
| 434 | * The notion of page is replaced by the term wunit (write-unit) to stay |
| 435 | * consistent with the ->writesize field. |
| 436 | * |
| 437 | * The @wunit argument can be extracted from an absolute offset using |
| 438 | * mtd_offset_to_wunit(). @info is filled with the pairing information attached |
| 439 | * to @wunit. |
| 440 | * |
| 441 | * From the pairing info the MTD user can find all the wunits paired with |
| 442 | * @wunit using the following loop: |
| 443 | * |
| 444 | * for (i = 0; i < mtd_pairing_groups(mtd); i++) { |
| 445 | * info.pair = i; |
| 446 | * mtd_pairing_info_to_wunit(mtd, &info); |
| 447 | * ... |
| 448 | * } |
| 449 | */ |
| 450 | int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit, |
| 451 | struct mtd_pairing_info *info) |
| 452 | { |
| 453 | struct mtd_info *master = mtd_get_master(mtd); |
| 454 | int npairs = mtd_wunit_per_eb(master) / mtd_pairing_groups(master); |
| 455 | |
| 456 | if (wunit < 0 || wunit >= npairs) |
| 457 | return -EINVAL; |
| 458 | |
| 459 | if (master->pairing && master->pairing->get_info) |
| 460 | return master->pairing->get_info(master, wunit, info); |
| 461 | |
| 462 | info->group = 0; |
| 463 | info->pair = wunit; |
| 464 | |
| 465 | return 0; |
| 466 | } |
| 467 | EXPORT_SYMBOL_GPL(mtd_wunit_to_pairing_info); |
| 468 | |
| 469 | /** |
| 470 | * mtd_pairing_info_to_wunit - get wunit from pairing information |
| 471 | * @mtd: pointer to new MTD device info structure |
| 472 | * @info: pairing information struct |
| 473 | * |
| 474 | * Returns a positive number representing the wunit associated to the info |
| 475 | * struct, or a negative error code. |
| 476 | * |
| 477 | * This is the reverse of mtd_wunit_to_pairing_info(), and can help one to |
| 478 | * iterate over all wunits of a given pair (see mtd_wunit_to_pairing_info() |
| 479 | * doc). |
| 480 | * |
| 481 | * It can also be used to only program the first page of each pair (i.e. |
| 482 | * page attached to group 0), which allows one to use an MLC NAND in |
| 483 | * software-emulated SLC mode: |
| 484 | * |
| 485 | * info.group = 0; |
| 486 | * npairs = mtd_wunit_per_eb(mtd) / mtd_pairing_groups(mtd); |
| 487 | * for (info.pair = 0; info.pair < npairs; info.pair++) { |
| 488 | * wunit = mtd_pairing_info_to_wunit(mtd, &info); |
| 489 | * mtd_write(mtd, mtd_wunit_to_offset(mtd, blkoffs, wunit), |
| 490 | * mtd->writesize, &retlen, buf + (i * mtd->writesize)); |
| 491 | * } |
| 492 | */ |
| 493 | int mtd_pairing_info_to_wunit(struct mtd_info *mtd, |
| 494 | const struct mtd_pairing_info *info) |
| 495 | { |
| 496 | struct mtd_info *master = mtd_get_master(mtd); |
| 497 | int ngroups = mtd_pairing_groups(master); |
| 498 | int npairs = mtd_wunit_per_eb(master) / ngroups; |
| 499 | |
| 500 | if (!info || info->pair < 0 || info->pair >= npairs || |
| 501 | info->group < 0 || info->group >= ngroups) |
| 502 | return -EINVAL; |
| 503 | |
| 504 | if (master->pairing && master->pairing->get_wunit) |
| 505 | return mtd->pairing->get_wunit(master, info); |
| 506 | |
| 507 | return info->pair; |
| 508 | } |
| 509 | EXPORT_SYMBOL_GPL(mtd_pairing_info_to_wunit); |
| 510 | |
| 511 | /** |
| 512 | * mtd_pairing_groups - get the number of pairing groups |
| 513 | * @mtd: pointer to new MTD device info structure |
| 514 | * |
| 515 | * Returns the number of pairing groups. |
| 516 | * |
| 517 | * This number is usually equal to the number of bits exposed by a single |
| 518 | * cell, and can be used in conjunction with mtd_pairing_info_to_wunit() |
| 519 | * to iterate over all pages of a given pair. |
| 520 | */ |
| 521 | int mtd_pairing_groups(struct mtd_info *mtd) |
| 522 | { |
| 523 | struct mtd_info *master = mtd_get_master(mtd); |
| 524 | |
| 525 | if (!master->pairing || !master->pairing->ngroups) |
| 526 | return 1; |
| 527 | |
| 528 | return master->pairing->ngroups; |
| 529 | } |
| 530 | EXPORT_SYMBOL_GPL(mtd_pairing_groups); |
| 531 | |
| 532 | static int mtd_nvmem_reg_read(void *priv, unsigned int offset, |
| 533 | void *val, size_t bytes) |
| 534 | { |
| 535 | struct mtd_info *mtd = priv; |
| 536 | size_t retlen; |
| 537 | int err; |
| 538 | |
| 539 | err = mtd_read(mtd, offset, bytes, &retlen, val); |
| 540 | if (err && err != -EUCLEAN) |
| 541 | return err; |
| 542 | |
| 543 | return retlen == bytes ? 0 : -EIO; |
| 544 | } |
| 545 | |
| 546 | static int mtd_nvmem_add(struct mtd_info *mtd) |
| 547 | { |
| 548 | struct device_node *node = mtd_get_of_node(mtd); |
| 549 | struct nvmem_config config = {}; |
| 550 | |
| 551 | config.id = NVMEM_DEVID_NONE; |
| 552 | config.dev = &mtd->dev; |
| 553 | config.name = dev_name(&mtd->dev); |
| 554 | config.owner = THIS_MODULE; |
| 555 | config.reg_read = mtd_nvmem_reg_read; |
| 556 | config.size = mtd->size; |
| 557 | config.word_size = 1; |
| 558 | config.stride = 1; |
| 559 | config.read_only = true; |
| 560 | config.root_only = true; |
| 561 | config.ignore_wp = true; |
| 562 | config.no_of_node = !of_device_is_compatible(node, "nvmem-cells"); |
| 563 | config.priv = mtd; |
| 564 | |
| 565 | mtd->nvmem = nvmem_register(&config); |
| 566 | if (IS_ERR(mtd->nvmem)) { |
| 567 | /* Just ignore if there is no NVMEM support in the kernel */ |
| 568 | if (PTR_ERR(mtd->nvmem) == -EOPNOTSUPP) |
| 569 | mtd->nvmem = NULL; |
| 570 | else |
| 571 | return dev_err_probe(&mtd->dev, PTR_ERR(mtd->nvmem), |
| 572 | "Failed to register NVMEM device\n"); |
| 573 | } |
| 574 | |
| 575 | return 0; |
| 576 | } |
| 577 | |
| 578 | static void mtd_check_of_node(struct mtd_info *mtd) |
| 579 | { |
| 580 | struct device_node *partitions, *parent_dn, *mtd_dn = NULL; |
| 581 | const char *pname, *prefix = "partition-"; |
| 582 | int plen, mtd_name_len, offset, prefix_len; |
| 583 | |
| 584 | /* Check if MTD already has a device node */ |
| 585 | if (mtd_get_of_node(mtd)) |
| 586 | return; |
| 587 | |
| 588 | if (!mtd_is_partition(mtd)) |
| 589 | return; |
| 590 | |
| 591 | parent_dn = of_node_get(mtd_get_of_node(mtd->parent)); |
| 592 | if (!parent_dn) |
| 593 | return; |
| 594 | |
| 595 | if (mtd_is_partition(mtd->parent)) |
| 596 | partitions = of_node_get(parent_dn); |
| 597 | else |
| 598 | partitions = of_get_child_by_name(parent_dn, "partitions"); |
| 599 | if (!partitions) |
| 600 | goto exit_parent; |
| 601 | |
| 602 | prefix_len = strlen(prefix); |
| 603 | mtd_name_len = strlen(mtd->name); |
| 604 | |
| 605 | /* Search if a partition is defined with the same name */ |
| 606 | for_each_child_of_node(partitions, mtd_dn) { |
| 607 | /* Skip partition with no/wrong prefix */ |
| 608 | if (!of_node_name_prefix(mtd_dn, prefix)) |
| 609 | continue; |
| 610 | |
| 611 | /* Label have priority. Check that first */ |
| 612 | if (!of_property_read_string(mtd_dn, "label", &pname)) { |
| 613 | offset = 0; |
| 614 | } else { |
| 615 | pname = mtd_dn->name; |
| 616 | offset = prefix_len; |
| 617 | } |
| 618 | |
| 619 | plen = strlen(pname) - offset; |
| 620 | if (plen == mtd_name_len && |
| 621 | !strncmp(mtd->name, pname + offset, plen)) { |
| 622 | mtd_set_of_node(mtd, mtd_dn); |
| 623 | break; |
| 624 | } |
| 625 | } |
| 626 | |
| 627 | of_node_put(partitions); |
| 628 | exit_parent: |
| 629 | of_node_put(parent_dn); |
| 630 | } |
| 631 | |
| 632 | /** |
| 633 | * add_mtd_device - register an MTD device |
| 634 | * @mtd: pointer to new MTD device info structure |
| 635 | * |
| 636 | * Add a device to the list of MTD devices present in the system, and |
| 637 | * notify each currently active MTD 'user' of its arrival. Returns |
| 638 | * zero on success or non-zero on failure. |
| 639 | */ |
| 640 | |
| 641 | int add_mtd_device(struct mtd_info *mtd) |
| 642 | { |
| 643 | struct device_node *np = mtd_get_of_node(mtd); |
| 644 | struct mtd_info *master = mtd_get_master(mtd); |
| 645 | struct mtd_notifier *not; |
| 646 | int i, error, ofidx; |
| 647 | |
| 648 | /* |
| 649 | * May occur, for instance, on buggy drivers which call |
| 650 | * mtd_device_parse_register() multiple times on the same master MTD, |
| 651 | * especially with CONFIG_MTD_PARTITIONED_MASTER=y. |
| 652 | */ |
| 653 | if (WARN_ONCE(mtd->dev.type, "MTD already registered\n")) |
| 654 | return -EEXIST; |
| 655 | |
| 656 | BUG_ON(mtd->writesize == 0); |
| 657 | |
| 658 | /* |
| 659 | * MTD drivers should implement ->_{write,read}() or |
| 660 | * ->_{write,read}_oob(), but not both. |
| 661 | */ |
| 662 | if (WARN_ON((mtd->_write && mtd->_write_oob) || |
| 663 | (mtd->_read && mtd->_read_oob))) |
| 664 | return -EINVAL; |
| 665 | |
| 666 | if (WARN_ON((!mtd->erasesize || !master->_erase) && |
| 667 | !(mtd->flags & MTD_NO_ERASE))) |
| 668 | return -EINVAL; |
| 669 | |
| 670 | /* |
| 671 | * MTD_SLC_ON_MLC_EMULATION can only be set on partitions, when the |
| 672 | * master is an MLC NAND and has a proper pairing scheme defined. |
| 673 | * We also reject masters that implement ->_writev() for now, because |
| 674 | * NAND controller drivers don't implement this hook, and adding the |
| 675 | * SLC -> MLC address/length conversion to this path is useless if we |
| 676 | * don't have a user. |
| 677 | */ |
| 678 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION && |
| 679 | (!mtd_is_partition(mtd) || master->type != MTD_MLCNANDFLASH || |
| 680 | !master->pairing || master->_writev)) |
| 681 | return -EINVAL; |
| 682 | |
| 683 | mutex_lock(&mtd_table_mutex); |
| 684 | |
| 685 | ofidx = -1; |
| 686 | if (np) |
| 687 | ofidx = of_alias_get_id(np, "mtd"); |
| 688 | if (ofidx >= 0) |
| 689 | i = idr_alloc(&mtd_idr, mtd, ofidx, ofidx + 1, GFP_KERNEL); |
| 690 | else |
| 691 | i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL); |
| 692 | if (i < 0) { |
| 693 | error = i; |
| 694 | goto fail_locked; |
| 695 | } |
| 696 | |
| 697 | mtd->index = i; |
| 698 | kref_init(&mtd->refcnt); |
| 699 | |
| 700 | /* default value if not set by driver */ |
| 701 | if (mtd->bitflip_threshold == 0) |
| 702 | mtd->bitflip_threshold = mtd->ecc_strength; |
| 703 | |
| 704 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 705 | int ngroups = mtd_pairing_groups(master); |
| 706 | |
| 707 | mtd->erasesize /= ngroups; |
| 708 | mtd->size = (u64)mtd_div_by_eb(mtd->size, master) * |
| 709 | mtd->erasesize; |
| 710 | } |
| 711 | |
| 712 | if (is_power_of_2(mtd->erasesize)) |
| 713 | mtd->erasesize_shift = ffs(mtd->erasesize) - 1; |
| 714 | else |
| 715 | mtd->erasesize_shift = 0; |
| 716 | |
| 717 | if (is_power_of_2(mtd->writesize)) |
| 718 | mtd->writesize_shift = ffs(mtd->writesize) - 1; |
| 719 | else |
| 720 | mtd->writesize_shift = 0; |
| 721 | |
| 722 | mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1; |
| 723 | mtd->writesize_mask = (1 << mtd->writesize_shift) - 1; |
| 724 | |
| 725 | /* Some chips always power up locked. Unlock them now */ |
| 726 | if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) { |
| 727 | error = mtd_unlock(mtd, 0, mtd->size); |
| 728 | if (error && error != -EOPNOTSUPP) |
| 729 | printk(KERN_WARNING |
| 730 | "%s: unlock failed, writes may not work\n", |
| 731 | mtd->name); |
| 732 | /* Ignore unlock failures? */ |
| 733 | error = 0; |
| 734 | } |
| 735 | |
| 736 | /* Caller should have set dev.parent to match the |
| 737 | * physical device, if appropriate. |
| 738 | */ |
| 739 | mtd->dev.type = &mtd_devtype; |
| 740 | mtd->dev.class = &mtd_class; |
| 741 | mtd->dev.devt = MTD_DEVT(i); |
| 742 | dev_set_name(&mtd->dev, "mtd%d", i); |
| 743 | dev_set_drvdata(&mtd->dev, mtd); |
| 744 | mtd_check_of_node(mtd); |
| 745 | of_node_get(mtd_get_of_node(mtd)); |
| 746 | error = device_register(&mtd->dev); |
| 747 | if (error) { |
| 748 | put_device(&mtd->dev); |
| 749 | goto fail_added; |
| 750 | } |
| 751 | |
| 752 | /* Add the nvmem provider */ |
| 753 | error = mtd_nvmem_add(mtd); |
| 754 | if (error) |
| 755 | goto fail_nvmem_add; |
| 756 | |
| 757 | mtd_debugfs_populate(mtd); |
| 758 | |
| 759 | device_create(&mtd_class, mtd->dev.parent, MTD_DEVT(i) + 1, NULL, |
| 760 | "mtd%dro", i); |
| 761 | |
| 762 | pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name); |
| 763 | /* No need to get a refcount on the module containing |
| 764 | the notifier, since we hold the mtd_table_mutex */ |
| 765 | list_for_each_entry(not, &mtd_notifiers, list) |
| 766 | not->add(mtd); |
| 767 | |
| 768 | mutex_unlock(&mtd_table_mutex); |
| 769 | |
| 770 | if (of_property_read_bool(mtd_get_of_node(mtd), "linux,rootfs")) { |
| 771 | if (IS_BUILTIN(CONFIG_MTD)) { |
| 772 | pr_info("mtd: setting mtd%d (%s) as root device\n", mtd->index, mtd->name); |
| 773 | ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, mtd->index); |
| 774 | } else { |
| 775 | pr_warn("mtd: can't set mtd%d (%s) as root device - mtd must be builtin\n", |
| 776 | mtd->index, mtd->name); |
| 777 | } |
| 778 | } |
| 779 | |
| 780 | /* We _know_ we aren't being removed, because |
| 781 | our caller is still holding us here. So none |
| 782 | of this try_ nonsense, and no bitching about it |
| 783 | either. :) */ |
| 784 | __module_get(THIS_MODULE); |
| 785 | return 0; |
| 786 | |
| 787 | fail_nvmem_add: |
| 788 | device_unregister(&mtd->dev); |
| 789 | fail_added: |
| 790 | of_node_put(mtd_get_of_node(mtd)); |
| 791 | idr_remove(&mtd_idr, i); |
| 792 | fail_locked: |
| 793 | mutex_unlock(&mtd_table_mutex); |
| 794 | return error; |
| 795 | } |
| 796 | |
| 797 | /** |
| 798 | * del_mtd_device - unregister an MTD device |
| 799 | * @mtd: pointer to MTD device info structure |
| 800 | * |
| 801 | * Remove a device from the list of MTD devices present in the system, |
| 802 | * and notify each currently active MTD 'user' of its departure. |
| 803 | * Returns zero on success or 1 on failure, which currently will happen |
| 804 | * if the requested device does not appear to be present in the list. |
| 805 | */ |
| 806 | |
| 807 | int del_mtd_device(struct mtd_info *mtd) |
| 808 | { |
| 809 | int ret; |
| 810 | struct mtd_notifier *not; |
| 811 | |
| 812 | mutex_lock(&mtd_table_mutex); |
| 813 | |
| 814 | if (idr_find(&mtd_idr, mtd->index) != mtd) { |
| 815 | ret = -ENODEV; |
| 816 | goto out_error; |
| 817 | } |
| 818 | |
| 819 | /* No need to get a refcount on the module containing |
| 820 | the notifier, since we hold the mtd_table_mutex */ |
| 821 | list_for_each_entry(not, &mtd_notifiers, list) |
| 822 | not->remove(mtd); |
| 823 | |
| 824 | kref_put(&mtd->refcnt, mtd_device_release); |
| 825 | ret = 0; |
| 826 | |
| 827 | out_error: |
| 828 | mutex_unlock(&mtd_table_mutex); |
| 829 | return ret; |
| 830 | } |
| 831 | |
| 832 | /* |
| 833 | * Set a few defaults based on the parent devices, if not provided by the |
| 834 | * driver |
| 835 | */ |
| 836 | static void mtd_set_dev_defaults(struct mtd_info *mtd) |
| 837 | { |
| 838 | if (mtd->dev.parent) { |
| 839 | if (!mtd->owner && mtd->dev.parent->driver) |
| 840 | mtd->owner = mtd->dev.parent->driver->owner; |
| 841 | if (!mtd->name) |
| 842 | mtd->name = dev_name(mtd->dev.parent); |
| 843 | } else { |
| 844 | pr_debug("mtd device won't show a device symlink in sysfs\n"); |
| 845 | } |
| 846 | |
| 847 | INIT_LIST_HEAD(&mtd->partitions); |
| 848 | mutex_init(&mtd->master.partitions_lock); |
| 849 | mutex_init(&mtd->master.chrdev_lock); |
| 850 | } |
| 851 | |
| 852 | static ssize_t mtd_otp_size(struct mtd_info *mtd, bool is_user) |
| 853 | { |
| 854 | struct otp_info *info; |
| 855 | ssize_t size = 0; |
| 856 | unsigned int i; |
| 857 | size_t retlen; |
| 858 | int ret; |
| 859 | |
| 860 | info = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 861 | if (!info) |
| 862 | return -ENOMEM; |
| 863 | |
| 864 | if (is_user) |
| 865 | ret = mtd_get_user_prot_info(mtd, PAGE_SIZE, &retlen, info); |
| 866 | else |
| 867 | ret = mtd_get_fact_prot_info(mtd, PAGE_SIZE, &retlen, info); |
| 868 | if (ret) |
| 869 | goto err; |
| 870 | |
| 871 | for (i = 0; i < retlen / sizeof(*info); i++) |
| 872 | size += info[i].length; |
| 873 | |
| 874 | kfree(info); |
| 875 | return size; |
| 876 | |
| 877 | err: |
| 878 | kfree(info); |
| 879 | |
| 880 | /* ENODATA means there is no OTP region. */ |
| 881 | return ret == -ENODATA ? 0 : ret; |
| 882 | } |
| 883 | |
| 884 | static struct nvmem_device *mtd_otp_nvmem_register(struct mtd_info *mtd, |
| 885 | const char *compatible, |
| 886 | int size, |
| 887 | nvmem_reg_read_t reg_read) |
| 888 | { |
| 889 | struct nvmem_device *nvmem = NULL; |
| 890 | struct nvmem_config config = {}; |
| 891 | struct device_node *np; |
| 892 | |
| 893 | /* DT binding is optional */ |
| 894 | np = of_get_compatible_child(mtd->dev.of_node, compatible); |
| 895 | |
| 896 | /* OTP nvmem will be registered on the physical device */ |
| 897 | config.dev = mtd->dev.parent; |
| 898 | config.name = compatible; |
| 899 | config.id = NVMEM_DEVID_AUTO; |
| 900 | config.owner = THIS_MODULE; |
| 901 | config.type = NVMEM_TYPE_OTP; |
| 902 | config.root_only = true; |
| 903 | config.ignore_wp = true; |
| 904 | config.reg_read = reg_read; |
| 905 | config.size = size; |
| 906 | config.of_node = np; |
| 907 | config.priv = mtd; |
| 908 | |
| 909 | nvmem = nvmem_register(&config); |
| 910 | /* Just ignore if there is no NVMEM support in the kernel */ |
| 911 | if (IS_ERR(nvmem) && PTR_ERR(nvmem) == -EOPNOTSUPP) |
| 912 | nvmem = NULL; |
| 913 | |
| 914 | of_node_put(np); |
| 915 | |
| 916 | return nvmem; |
| 917 | } |
| 918 | |
| 919 | static int mtd_nvmem_user_otp_reg_read(void *priv, unsigned int offset, |
| 920 | void *val, size_t bytes) |
| 921 | { |
| 922 | struct mtd_info *mtd = priv; |
| 923 | size_t retlen; |
| 924 | int ret; |
| 925 | |
| 926 | ret = mtd_read_user_prot_reg(mtd, offset, bytes, &retlen, val); |
| 927 | if (ret) |
| 928 | return ret; |
| 929 | |
| 930 | return retlen == bytes ? 0 : -EIO; |
| 931 | } |
| 932 | |
| 933 | static int mtd_nvmem_fact_otp_reg_read(void *priv, unsigned int offset, |
| 934 | void *val, size_t bytes) |
| 935 | { |
| 936 | struct mtd_info *mtd = priv; |
| 937 | size_t retlen; |
| 938 | int ret; |
| 939 | |
| 940 | ret = mtd_read_fact_prot_reg(mtd, offset, bytes, &retlen, val); |
| 941 | if (ret) |
| 942 | return ret; |
| 943 | |
| 944 | return retlen == bytes ? 0 : -EIO; |
| 945 | } |
| 946 | |
| 947 | static int mtd_otp_nvmem_add(struct mtd_info *mtd) |
| 948 | { |
| 949 | struct device *dev = mtd->dev.parent; |
| 950 | struct nvmem_device *nvmem; |
| 951 | ssize_t size; |
| 952 | int err; |
| 953 | |
| 954 | if (mtd->_get_user_prot_info && mtd->_read_user_prot_reg) { |
| 955 | size = mtd_otp_size(mtd, true); |
| 956 | if (size < 0) |
| 957 | return size; |
| 958 | |
| 959 | if (size > 0) { |
| 960 | nvmem = mtd_otp_nvmem_register(mtd, "user-otp", size, |
| 961 | mtd_nvmem_user_otp_reg_read); |
| 962 | if (IS_ERR(nvmem)) { |
| 963 | err = PTR_ERR(nvmem); |
| 964 | goto err; |
| 965 | } |
| 966 | mtd->otp_user_nvmem = nvmem; |
| 967 | } |
| 968 | } |
| 969 | |
| 970 | if (mtd->_get_fact_prot_info && mtd->_read_fact_prot_reg) { |
| 971 | size = mtd_otp_size(mtd, false); |
| 972 | if (size < 0) { |
| 973 | err = size; |
| 974 | goto err; |
| 975 | } |
| 976 | |
| 977 | if (size > 0) { |
| 978 | /* |
| 979 | * The factory OTP contains thing such as a unique serial |
| 980 | * number and is small, so let's read it out and put it |
| 981 | * into the entropy pool. |
| 982 | */ |
| 983 | void *otp; |
| 984 | |
| 985 | otp = kmalloc(size, GFP_KERNEL); |
| 986 | if (!otp) { |
| 987 | err = -ENOMEM; |
| 988 | goto err; |
| 989 | } |
| 990 | err = mtd_nvmem_fact_otp_reg_read(mtd, 0, otp, size); |
| 991 | if (err < 0) { |
| 992 | kfree(otp); |
| 993 | goto err; |
| 994 | } |
| 995 | add_device_randomness(otp, err); |
| 996 | kfree(otp); |
| 997 | |
| 998 | nvmem = mtd_otp_nvmem_register(mtd, "factory-otp", size, |
| 999 | mtd_nvmem_fact_otp_reg_read); |
| 1000 | if (IS_ERR(nvmem)) { |
| 1001 | err = PTR_ERR(nvmem); |
| 1002 | goto err; |
| 1003 | } |
| 1004 | mtd->otp_factory_nvmem = nvmem; |
| 1005 | } |
| 1006 | } |
| 1007 | |
| 1008 | return 0; |
| 1009 | |
| 1010 | err: |
| 1011 | nvmem_unregister(mtd->otp_user_nvmem); |
| 1012 | return dev_err_probe(dev, err, "Failed to register OTP NVMEM device\n"); |
| 1013 | } |
| 1014 | |
| 1015 | /** |
| 1016 | * mtd_device_parse_register - parse partitions and register an MTD device. |
| 1017 | * |
| 1018 | * @mtd: the MTD device to register |
| 1019 | * @types: the list of MTD partition probes to try, see |
| 1020 | * 'parse_mtd_partitions()' for more information |
| 1021 | * @parser_data: MTD partition parser-specific data |
| 1022 | * @parts: fallback partition information to register, if parsing fails; |
| 1023 | * only valid if %nr_parts > %0 |
| 1024 | * @nr_parts: the number of partitions in parts, if zero then the full |
| 1025 | * MTD device is registered if no partition info is found |
| 1026 | * |
| 1027 | * This function aggregates MTD partitions parsing (done by |
| 1028 | * 'parse_mtd_partitions()') and MTD device and partitions registering. It |
| 1029 | * basically follows the most common pattern found in many MTD drivers: |
| 1030 | * |
| 1031 | * * If the MTD_PARTITIONED_MASTER option is set, then the device as a whole is |
| 1032 | * registered first. |
| 1033 | * * Then It tries to probe partitions on MTD device @mtd using parsers |
| 1034 | * specified in @types (if @types is %NULL, then the default list of parsers |
| 1035 | * is used, see 'parse_mtd_partitions()' for more information). If none are |
| 1036 | * found this functions tries to fallback to information specified in |
| 1037 | * @parts/@nr_parts. |
| 1038 | * * If no partitions were found this function just registers the MTD device |
| 1039 | * @mtd and exits. |
| 1040 | * |
| 1041 | * Returns zero in case of success and a negative error code in case of failure. |
| 1042 | */ |
| 1043 | int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types, |
| 1044 | struct mtd_part_parser_data *parser_data, |
| 1045 | const struct mtd_partition *parts, |
| 1046 | int nr_parts) |
| 1047 | { |
| 1048 | int ret; |
| 1049 | |
| 1050 | mtd_set_dev_defaults(mtd); |
| 1051 | |
| 1052 | ret = mtd_otp_nvmem_add(mtd); |
| 1053 | if (ret) |
| 1054 | goto out; |
| 1055 | |
| 1056 | if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) { |
| 1057 | ret = add_mtd_device(mtd); |
| 1058 | if (ret) |
| 1059 | goto out; |
| 1060 | } |
| 1061 | |
| 1062 | /* Prefer parsed partitions over driver-provided fallback */ |
| 1063 | ret = parse_mtd_partitions(mtd, types, parser_data); |
| 1064 | if (ret == -EPROBE_DEFER) |
| 1065 | goto out; |
| 1066 | |
| 1067 | if (ret > 0) |
| 1068 | ret = 0; |
| 1069 | else if (nr_parts) |
| 1070 | ret = add_mtd_partitions(mtd, parts, nr_parts); |
| 1071 | else if (!device_is_registered(&mtd->dev)) |
| 1072 | ret = add_mtd_device(mtd); |
| 1073 | else |
| 1074 | ret = 0; |
| 1075 | |
| 1076 | if (ret) |
| 1077 | goto out; |
| 1078 | |
| 1079 | /* |
| 1080 | * FIXME: some drivers unfortunately call this function more than once. |
| 1081 | * So we have to check if we've already assigned the reboot notifier. |
| 1082 | * |
| 1083 | * Generally, we can make multiple calls work for most cases, but it |
| 1084 | * does cause problems with parse_mtd_partitions() above (e.g., |
| 1085 | * cmdlineparts will register partitions more than once). |
| 1086 | */ |
| 1087 | WARN_ONCE(mtd->_reboot && mtd->reboot_notifier.notifier_call, |
| 1088 | "MTD already registered\n"); |
| 1089 | if (mtd->_reboot && !mtd->reboot_notifier.notifier_call) { |
| 1090 | mtd->reboot_notifier.notifier_call = mtd_reboot_notifier; |
| 1091 | register_reboot_notifier(&mtd->reboot_notifier); |
| 1092 | } |
| 1093 | |
| 1094 | out: |
| 1095 | if (ret) { |
| 1096 | nvmem_unregister(mtd->otp_user_nvmem); |
| 1097 | nvmem_unregister(mtd->otp_factory_nvmem); |
| 1098 | } |
| 1099 | |
| 1100 | if (ret && device_is_registered(&mtd->dev)) |
| 1101 | del_mtd_device(mtd); |
| 1102 | |
| 1103 | return ret; |
| 1104 | } |
| 1105 | EXPORT_SYMBOL_GPL(mtd_device_parse_register); |
| 1106 | |
| 1107 | /** |
| 1108 | * mtd_device_unregister - unregister an existing MTD device. |
| 1109 | * |
| 1110 | * @master: the MTD device to unregister. This will unregister both the master |
| 1111 | * and any partitions if registered. |
| 1112 | */ |
| 1113 | int mtd_device_unregister(struct mtd_info *master) |
| 1114 | { |
| 1115 | int err; |
| 1116 | |
| 1117 | if (master->_reboot) { |
| 1118 | unregister_reboot_notifier(&master->reboot_notifier); |
| 1119 | memset(&master->reboot_notifier, 0, sizeof(master->reboot_notifier)); |
| 1120 | } |
| 1121 | |
| 1122 | nvmem_unregister(master->otp_user_nvmem); |
| 1123 | nvmem_unregister(master->otp_factory_nvmem); |
| 1124 | |
| 1125 | err = del_mtd_partitions(master); |
| 1126 | if (err) |
| 1127 | return err; |
| 1128 | |
| 1129 | if (!device_is_registered(&master->dev)) |
| 1130 | return 0; |
| 1131 | |
| 1132 | return del_mtd_device(master); |
| 1133 | } |
| 1134 | EXPORT_SYMBOL_GPL(mtd_device_unregister); |
| 1135 | |
| 1136 | /** |
| 1137 | * register_mtd_user - register a 'user' of MTD devices. |
| 1138 | * @new: pointer to notifier info structure |
| 1139 | * |
| 1140 | * Registers a pair of callbacks function to be called upon addition |
| 1141 | * or removal of MTD devices. Causes the 'add' callback to be immediately |
| 1142 | * invoked for each MTD device currently present in the system. |
| 1143 | */ |
| 1144 | void register_mtd_user (struct mtd_notifier *new) |
| 1145 | { |
| 1146 | struct mtd_info *mtd; |
| 1147 | |
| 1148 | mutex_lock(&mtd_table_mutex); |
| 1149 | |
| 1150 | list_add(&new->list, &mtd_notifiers); |
| 1151 | |
| 1152 | __module_get(THIS_MODULE); |
| 1153 | |
| 1154 | mtd_for_each_device(mtd) |
| 1155 | new->add(mtd); |
| 1156 | |
| 1157 | mutex_unlock(&mtd_table_mutex); |
| 1158 | } |
| 1159 | EXPORT_SYMBOL_GPL(register_mtd_user); |
| 1160 | |
| 1161 | /** |
| 1162 | * unregister_mtd_user - unregister a 'user' of MTD devices. |
| 1163 | * @old: pointer to notifier info structure |
| 1164 | * |
| 1165 | * Removes a callback function pair from the list of 'users' to be |
| 1166 | * notified upon addition or removal of MTD devices. Causes the |
| 1167 | * 'remove' callback to be immediately invoked for each MTD device |
| 1168 | * currently present in the system. |
| 1169 | */ |
| 1170 | int unregister_mtd_user (struct mtd_notifier *old) |
| 1171 | { |
| 1172 | struct mtd_info *mtd; |
| 1173 | |
| 1174 | mutex_lock(&mtd_table_mutex); |
| 1175 | |
| 1176 | module_put(THIS_MODULE); |
| 1177 | |
| 1178 | mtd_for_each_device(mtd) |
| 1179 | old->remove(mtd); |
| 1180 | |
| 1181 | list_del(&old->list); |
| 1182 | mutex_unlock(&mtd_table_mutex); |
| 1183 | return 0; |
| 1184 | } |
| 1185 | EXPORT_SYMBOL_GPL(unregister_mtd_user); |
| 1186 | |
| 1187 | /** |
| 1188 | * get_mtd_device - obtain a validated handle for an MTD device |
| 1189 | * @mtd: last known address of the required MTD device |
| 1190 | * @num: internal device number of the required MTD device |
| 1191 | * |
| 1192 | * Given a number and NULL address, return the num'th entry in the device |
| 1193 | * table, if any. Given an address and num == -1, search the device table |
| 1194 | * for a device with that address and return if it's still present. Given |
| 1195 | * both, return the num'th driver only if its address matches. Return |
| 1196 | * error code if not. |
| 1197 | */ |
| 1198 | struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) |
| 1199 | { |
| 1200 | struct mtd_info *ret = NULL, *other; |
| 1201 | int err = -ENODEV; |
| 1202 | |
| 1203 | mutex_lock(&mtd_table_mutex); |
| 1204 | |
| 1205 | if (num == -1) { |
| 1206 | mtd_for_each_device(other) { |
| 1207 | if (other == mtd) { |
| 1208 | ret = mtd; |
| 1209 | break; |
| 1210 | } |
| 1211 | } |
| 1212 | } else if (num >= 0) { |
| 1213 | ret = idr_find(&mtd_idr, num); |
| 1214 | if (mtd && mtd != ret) |
| 1215 | ret = NULL; |
| 1216 | } |
| 1217 | |
| 1218 | if (!ret) { |
| 1219 | ret = ERR_PTR(err); |
| 1220 | goto out; |
| 1221 | } |
| 1222 | |
| 1223 | err = __get_mtd_device(ret); |
| 1224 | if (err) |
| 1225 | ret = ERR_PTR(err); |
| 1226 | out: |
| 1227 | mutex_unlock(&mtd_table_mutex); |
| 1228 | return ret; |
| 1229 | } |
| 1230 | EXPORT_SYMBOL_GPL(get_mtd_device); |
| 1231 | |
| 1232 | |
| 1233 | int __get_mtd_device(struct mtd_info *mtd) |
| 1234 | { |
| 1235 | struct mtd_info *master = mtd_get_master(mtd); |
| 1236 | int err; |
| 1237 | |
| 1238 | if (master->_get_device) { |
| 1239 | err = master->_get_device(mtd); |
| 1240 | if (err) |
| 1241 | return err; |
| 1242 | } |
| 1243 | |
| 1244 | if (!try_module_get(master->owner)) { |
| 1245 | if (master->_put_device) |
| 1246 | master->_put_device(master); |
| 1247 | return -ENODEV; |
| 1248 | } |
| 1249 | |
| 1250 | while (mtd) { |
| 1251 | if (mtd != master) |
| 1252 | kref_get(&mtd->refcnt); |
| 1253 | mtd = mtd->parent; |
| 1254 | } |
| 1255 | |
| 1256 | if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) |
| 1257 | kref_get(&master->refcnt); |
| 1258 | |
| 1259 | return 0; |
| 1260 | } |
| 1261 | EXPORT_SYMBOL_GPL(__get_mtd_device); |
| 1262 | |
| 1263 | /** |
| 1264 | * of_get_mtd_device_by_node - obtain an MTD device associated with a given node |
| 1265 | * |
| 1266 | * @np: device tree node |
| 1267 | */ |
| 1268 | struct mtd_info *of_get_mtd_device_by_node(struct device_node *np) |
| 1269 | { |
| 1270 | struct mtd_info *mtd = NULL; |
| 1271 | struct mtd_info *tmp; |
| 1272 | int err; |
| 1273 | |
| 1274 | mutex_lock(&mtd_table_mutex); |
| 1275 | |
| 1276 | err = -EPROBE_DEFER; |
| 1277 | mtd_for_each_device(tmp) { |
| 1278 | if (mtd_get_of_node(tmp) == np) { |
| 1279 | mtd = tmp; |
| 1280 | err = __get_mtd_device(mtd); |
| 1281 | break; |
| 1282 | } |
| 1283 | } |
| 1284 | |
| 1285 | mutex_unlock(&mtd_table_mutex); |
| 1286 | |
| 1287 | return err ? ERR_PTR(err) : mtd; |
| 1288 | } |
| 1289 | EXPORT_SYMBOL_GPL(of_get_mtd_device_by_node); |
| 1290 | |
| 1291 | /** |
| 1292 | * get_mtd_device_nm - obtain a validated handle for an MTD device by |
| 1293 | * device name |
| 1294 | * @name: MTD device name to open |
| 1295 | * |
| 1296 | * This function returns MTD device description structure in case of |
| 1297 | * success and an error code in case of failure. |
| 1298 | */ |
| 1299 | struct mtd_info *get_mtd_device_nm(const char *name) |
| 1300 | { |
| 1301 | int err = -ENODEV; |
| 1302 | struct mtd_info *mtd = NULL, *other; |
| 1303 | |
| 1304 | mutex_lock(&mtd_table_mutex); |
| 1305 | |
| 1306 | mtd_for_each_device(other) { |
| 1307 | if (!strcmp(name, other->name)) { |
| 1308 | mtd = other; |
| 1309 | break; |
| 1310 | } |
| 1311 | } |
| 1312 | |
| 1313 | if (!mtd) |
| 1314 | goto out_unlock; |
| 1315 | |
| 1316 | err = __get_mtd_device(mtd); |
| 1317 | if (err) |
| 1318 | goto out_unlock; |
| 1319 | |
| 1320 | mutex_unlock(&mtd_table_mutex); |
| 1321 | return mtd; |
| 1322 | |
| 1323 | out_unlock: |
| 1324 | mutex_unlock(&mtd_table_mutex); |
| 1325 | return ERR_PTR(err); |
| 1326 | } |
| 1327 | EXPORT_SYMBOL_GPL(get_mtd_device_nm); |
| 1328 | |
| 1329 | void put_mtd_device(struct mtd_info *mtd) |
| 1330 | { |
| 1331 | mutex_lock(&mtd_table_mutex); |
| 1332 | __put_mtd_device(mtd); |
| 1333 | mutex_unlock(&mtd_table_mutex); |
| 1334 | |
| 1335 | } |
| 1336 | EXPORT_SYMBOL_GPL(put_mtd_device); |
| 1337 | |
| 1338 | void __put_mtd_device(struct mtd_info *mtd) |
| 1339 | { |
| 1340 | struct mtd_info *master = mtd_get_master(mtd); |
| 1341 | |
| 1342 | while (mtd) { |
| 1343 | /* kref_put() can relese mtd, so keep a reference mtd->parent */ |
| 1344 | struct mtd_info *parent = mtd->parent; |
| 1345 | |
| 1346 | if (mtd != master) |
| 1347 | kref_put(&mtd->refcnt, mtd_device_release); |
| 1348 | mtd = parent; |
| 1349 | } |
| 1350 | |
| 1351 | if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) |
| 1352 | kref_put(&master->refcnt, mtd_device_release); |
| 1353 | |
| 1354 | module_put(master->owner); |
| 1355 | |
| 1356 | /* must be the last as master can be freed in the _put_device */ |
| 1357 | if (master->_put_device) |
| 1358 | master->_put_device(master); |
| 1359 | } |
| 1360 | EXPORT_SYMBOL_GPL(__put_mtd_device); |
| 1361 | |
| 1362 | /* |
| 1363 | * Erase is an synchronous operation. Device drivers are epected to return a |
| 1364 | * negative error code if the operation failed and update instr->fail_addr |
| 1365 | * to point the portion that was not properly erased. |
| 1366 | */ |
| 1367 | int mtd_erase(struct mtd_info *mtd, struct erase_info *instr) |
| 1368 | { |
| 1369 | struct mtd_info *master = mtd_get_master(mtd); |
| 1370 | u64 mst_ofs = mtd_get_master_ofs(mtd, 0); |
| 1371 | struct erase_info adjinstr; |
| 1372 | int ret; |
| 1373 | |
| 1374 | instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN; |
| 1375 | adjinstr = *instr; |
| 1376 | |
| 1377 | if (!mtd->erasesize || !master->_erase) |
| 1378 | return -ENOTSUPP; |
| 1379 | |
| 1380 | if (instr->addr >= mtd->size || instr->len > mtd->size - instr->addr) |
| 1381 | return -EINVAL; |
| 1382 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 1383 | return -EROFS; |
| 1384 | |
| 1385 | if (!instr->len) |
| 1386 | return 0; |
| 1387 | |
| 1388 | ledtrig_mtd_activity(); |
| 1389 | |
| 1390 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 1391 | adjinstr.addr = (loff_t)mtd_div_by_eb(instr->addr, mtd) * |
| 1392 | master->erasesize; |
| 1393 | adjinstr.len = ((u64)mtd_div_by_eb(instr->addr + instr->len, mtd) * |
| 1394 | master->erasesize) - |
| 1395 | adjinstr.addr; |
| 1396 | } |
| 1397 | |
| 1398 | adjinstr.addr += mst_ofs; |
| 1399 | |
| 1400 | ret = master->_erase(master, &adjinstr); |
| 1401 | |
| 1402 | if (adjinstr.fail_addr != MTD_FAIL_ADDR_UNKNOWN) { |
| 1403 | instr->fail_addr = adjinstr.fail_addr - mst_ofs; |
| 1404 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 1405 | instr->fail_addr = mtd_div_by_eb(instr->fail_addr, |
| 1406 | master); |
| 1407 | instr->fail_addr *= mtd->erasesize; |
| 1408 | } |
| 1409 | } |
| 1410 | |
| 1411 | return ret; |
| 1412 | } |
| 1413 | EXPORT_SYMBOL_GPL(mtd_erase); |
| 1414 | |
| 1415 | /* |
| 1416 | * This stuff for eXecute-In-Place. phys is optional and may be set to NULL. |
| 1417 | */ |
| 1418 | int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, |
| 1419 | void **virt, resource_size_t *phys) |
| 1420 | { |
| 1421 | struct mtd_info *master = mtd_get_master(mtd); |
| 1422 | |
| 1423 | *retlen = 0; |
| 1424 | *virt = NULL; |
| 1425 | if (phys) |
| 1426 | *phys = 0; |
| 1427 | if (!master->_point) |
| 1428 | return -EOPNOTSUPP; |
| 1429 | if (from < 0 || from >= mtd->size || len > mtd->size - from) |
| 1430 | return -EINVAL; |
| 1431 | if (!len) |
| 1432 | return 0; |
| 1433 | |
| 1434 | from = mtd_get_master_ofs(mtd, from); |
| 1435 | return master->_point(master, from, len, retlen, virt, phys); |
| 1436 | } |
| 1437 | EXPORT_SYMBOL_GPL(mtd_point); |
| 1438 | |
| 1439 | /* We probably shouldn't allow XIP if the unpoint isn't a NULL */ |
| 1440 | int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len) |
| 1441 | { |
| 1442 | struct mtd_info *master = mtd_get_master(mtd); |
| 1443 | |
| 1444 | if (!master->_unpoint) |
| 1445 | return -EOPNOTSUPP; |
| 1446 | if (from < 0 || from >= mtd->size || len > mtd->size - from) |
| 1447 | return -EINVAL; |
| 1448 | if (!len) |
| 1449 | return 0; |
| 1450 | return master->_unpoint(master, mtd_get_master_ofs(mtd, from), len); |
| 1451 | } |
| 1452 | EXPORT_SYMBOL_GPL(mtd_unpoint); |
| 1453 | |
| 1454 | /* |
| 1455 | * Allow NOMMU mmap() to directly map the device (if not NULL) |
| 1456 | * - return the address to which the offset maps |
| 1457 | * - return -ENOSYS to indicate refusal to do the mapping |
| 1458 | */ |
| 1459 | unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len, |
| 1460 | unsigned long offset, unsigned long flags) |
| 1461 | { |
| 1462 | size_t retlen; |
| 1463 | void *virt; |
| 1464 | int ret; |
| 1465 | |
| 1466 | ret = mtd_point(mtd, offset, len, &retlen, &virt, NULL); |
| 1467 | if (ret) |
| 1468 | return ret; |
| 1469 | if (retlen != len) { |
| 1470 | mtd_unpoint(mtd, offset, retlen); |
| 1471 | return -ENOSYS; |
| 1472 | } |
| 1473 | return (unsigned long)virt; |
| 1474 | } |
| 1475 | EXPORT_SYMBOL_GPL(mtd_get_unmapped_area); |
| 1476 | |
| 1477 | static void mtd_update_ecc_stats(struct mtd_info *mtd, struct mtd_info *master, |
| 1478 | const struct mtd_ecc_stats *old_stats) |
| 1479 | { |
| 1480 | struct mtd_ecc_stats diff; |
| 1481 | |
| 1482 | if (master == mtd) |
| 1483 | return; |
| 1484 | |
| 1485 | diff = master->ecc_stats; |
| 1486 | diff.failed -= old_stats->failed; |
| 1487 | diff.corrected -= old_stats->corrected; |
| 1488 | |
| 1489 | while (mtd->parent) { |
| 1490 | mtd->ecc_stats.failed += diff.failed; |
| 1491 | mtd->ecc_stats.corrected += diff.corrected; |
| 1492 | mtd = mtd->parent; |
| 1493 | } |
| 1494 | } |
| 1495 | |
| 1496 | int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, |
| 1497 | u_char *buf) |
| 1498 | { |
| 1499 | struct mtd_oob_ops ops = { |
| 1500 | .len = len, |
| 1501 | .datbuf = buf, |
| 1502 | }; |
| 1503 | int ret; |
| 1504 | |
| 1505 | ret = mtd_read_oob(mtd, from, &ops); |
| 1506 | *retlen = ops.retlen; |
| 1507 | |
| 1508 | return ret; |
| 1509 | } |
| 1510 | EXPORT_SYMBOL_GPL(mtd_read); |
| 1511 | |
| 1512 | int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, |
| 1513 | const u_char *buf) |
| 1514 | { |
| 1515 | struct mtd_oob_ops ops = { |
| 1516 | .len = len, |
| 1517 | .datbuf = (u8 *)buf, |
| 1518 | }; |
| 1519 | int ret; |
| 1520 | |
| 1521 | ret = mtd_write_oob(mtd, to, &ops); |
| 1522 | *retlen = ops.retlen; |
| 1523 | |
| 1524 | return ret; |
| 1525 | } |
| 1526 | EXPORT_SYMBOL_GPL(mtd_write); |
| 1527 | |
| 1528 | /* |
| 1529 | * In blackbox flight recorder like scenarios we want to make successful writes |
| 1530 | * in interrupt context. panic_write() is only intended to be called when its |
| 1531 | * known the kernel is about to panic and we need the write to succeed. Since |
| 1532 | * the kernel is not going to be running for much longer, this function can |
| 1533 | * break locks and delay to ensure the write succeeds (but not sleep). |
| 1534 | */ |
| 1535 | int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, |
| 1536 | const u_char *buf) |
| 1537 | { |
| 1538 | struct mtd_info *master = mtd_get_master(mtd); |
| 1539 | |
| 1540 | *retlen = 0; |
| 1541 | if (!master->_panic_write) |
| 1542 | return -EOPNOTSUPP; |
| 1543 | if (to < 0 || to >= mtd->size || len > mtd->size - to) |
| 1544 | return -EINVAL; |
| 1545 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 1546 | return -EROFS; |
| 1547 | if (!len) |
| 1548 | return 0; |
| 1549 | if (!master->oops_panic_write) |
| 1550 | master->oops_panic_write = true; |
| 1551 | |
| 1552 | return master->_panic_write(master, mtd_get_master_ofs(mtd, to), len, |
| 1553 | retlen, buf); |
| 1554 | } |
| 1555 | EXPORT_SYMBOL_GPL(mtd_panic_write); |
| 1556 | |
| 1557 | static int mtd_check_oob_ops(struct mtd_info *mtd, loff_t offs, |
| 1558 | struct mtd_oob_ops *ops) |
| 1559 | { |
| 1560 | /* |
| 1561 | * Some users are setting ->datbuf or ->oobbuf to NULL, but are leaving |
| 1562 | * ->len or ->ooblen uninitialized. Force ->len and ->ooblen to 0 in |
| 1563 | * this case. |
| 1564 | */ |
| 1565 | if (!ops->datbuf) |
| 1566 | ops->len = 0; |
| 1567 | |
| 1568 | if (!ops->oobbuf) |
| 1569 | ops->ooblen = 0; |
| 1570 | |
| 1571 | if (offs < 0 || offs + ops->len > mtd->size) |
| 1572 | return -EINVAL; |
| 1573 | |
| 1574 | if (ops->ooblen) { |
| 1575 | size_t maxooblen; |
| 1576 | |
| 1577 | if (ops->ooboffs >= mtd_oobavail(mtd, ops)) |
| 1578 | return -EINVAL; |
| 1579 | |
| 1580 | maxooblen = ((size_t)(mtd_div_by_ws(mtd->size, mtd) - |
| 1581 | mtd_div_by_ws(offs, mtd)) * |
| 1582 | mtd_oobavail(mtd, ops)) - ops->ooboffs; |
| 1583 | if (ops->ooblen > maxooblen) |
| 1584 | return -EINVAL; |
| 1585 | } |
| 1586 | |
| 1587 | return 0; |
| 1588 | } |
| 1589 | |
| 1590 | static int mtd_read_oob_std(struct mtd_info *mtd, loff_t from, |
| 1591 | struct mtd_oob_ops *ops) |
| 1592 | { |
| 1593 | struct mtd_info *master = mtd_get_master(mtd); |
| 1594 | int ret; |
| 1595 | |
| 1596 | from = mtd_get_master_ofs(mtd, from); |
| 1597 | if (master->_read_oob) |
| 1598 | ret = master->_read_oob(master, from, ops); |
| 1599 | else |
| 1600 | ret = master->_read(master, from, ops->len, &ops->retlen, |
| 1601 | ops->datbuf); |
| 1602 | |
| 1603 | return ret; |
| 1604 | } |
| 1605 | |
| 1606 | static int mtd_write_oob_std(struct mtd_info *mtd, loff_t to, |
| 1607 | struct mtd_oob_ops *ops) |
| 1608 | { |
| 1609 | struct mtd_info *master = mtd_get_master(mtd); |
| 1610 | int ret; |
| 1611 | |
| 1612 | to = mtd_get_master_ofs(mtd, to); |
| 1613 | if (master->_write_oob) |
| 1614 | ret = master->_write_oob(master, to, ops); |
| 1615 | else |
| 1616 | ret = master->_write(master, to, ops->len, &ops->retlen, |
| 1617 | ops->datbuf); |
| 1618 | |
| 1619 | return ret; |
| 1620 | } |
| 1621 | |
| 1622 | static int mtd_io_emulated_slc(struct mtd_info *mtd, loff_t start, bool read, |
| 1623 | struct mtd_oob_ops *ops) |
| 1624 | { |
| 1625 | struct mtd_info *master = mtd_get_master(mtd); |
| 1626 | int ngroups = mtd_pairing_groups(master); |
| 1627 | int npairs = mtd_wunit_per_eb(master) / ngroups; |
| 1628 | struct mtd_oob_ops adjops = *ops; |
| 1629 | unsigned int wunit, oobavail; |
| 1630 | struct mtd_pairing_info info; |
| 1631 | int max_bitflips = 0; |
| 1632 | u32 ebofs, pageofs; |
| 1633 | loff_t base, pos; |
| 1634 | |
| 1635 | ebofs = mtd_mod_by_eb(start, mtd); |
| 1636 | base = (loff_t)mtd_div_by_eb(start, mtd) * master->erasesize; |
| 1637 | info.group = 0; |
| 1638 | info.pair = mtd_div_by_ws(ebofs, mtd); |
| 1639 | pageofs = mtd_mod_by_ws(ebofs, mtd); |
| 1640 | oobavail = mtd_oobavail(mtd, ops); |
| 1641 | |
| 1642 | while (ops->retlen < ops->len || ops->oobretlen < ops->ooblen) { |
| 1643 | int ret; |
| 1644 | |
| 1645 | if (info.pair >= npairs) { |
| 1646 | info.pair = 0; |
| 1647 | base += master->erasesize; |
| 1648 | } |
| 1649 | |
| 1650 | wunit = mtd_pairing_info_to_wunit(master, &info); |
| 1651 | pos = mtd_wunit_to_offset(mtd, base, wunit); |
| 1652 | |
| 1653 | adjops.len = ops->len - ops->retlen; |
| 1654 | if (adjops.len > mtd->writesize - pageofs) |
| 1655 | adjops.len = mtd->writesize - pageofs; |
| 1656 | |
| 1657 | adjops.ooblen = ops->ooblen - ops->oobretlen; |
| 1658 | if (adjops.ooblen > oobavail - adjops.ooboffs) |
| 1659 | adjops.ooblen = oobavail - adjops.ooboffs; |
| 1660 | |
| 1661 | if (read) { |
| 1662 | ret = mtd_read_oob_std(mtd, pos + pageofs, &adjops); |
| 1663 | if (ret > 0) |
| 1664 | max_bitflips = max(max_bitflips, ret); |
| 1665 | } else { |
| 1666 | ret = mtd_write_oob_std(mtd, pos + pageofs, &adjops); |
| 1667 | } |
| 1668 | |
| 1669 | if (ret < 0) |
| 1670 | return ret; |
| 1671 | |
| 1672 | max_bitflips = max(max_bitflips, ret); |
| 1673 | ops->retlen += adjops.retlen; |
| 1674 | ops->oobretlen += adjops.oobretlen; |
| 1675 | adjops.datbuf += adjops.retlen; |
| 1676 | adjops.oobbuf += adjops.oobretlen; |
| 1677 | adjops.ooboffs = 0; |
| 1678 | pageofs = 0; |
| 1679 | info.pair++; |
| 1680 | } |
| 1681 | |
| 1682 | return max_bitflips; |
| 1683 | } |
| 1684 | |
| 1685 | int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops) |
| 1686 | { |
| 1687 | struct mtd_info *master = mtd_get_master(mtd); |
| 1688 | struct mtd_ecc_stats old_stats = master->ecc_stats; |
| 1689 | int ret_code; |
| 1690 | |
| 1691 | ops->retlen = ops->oobretlen = 0; |
| 1692 | |
| 1693 | ret_code = mtd_check_oob_ops(mtd, from, ops); |
| 1694 | if (ret_code) |
| 1695 | return ret_code; |
| 1696 | |
| 1697 | ledtrig_mtd_activity(); |
| 1698 | |
| 1699 | /* Check the validity of a potential fallback on mtd->_read */ |
| 1700 | if (!master->_read_oob && (!master->_read || ops->oobbuf)) |
| 1701 | return -EOPNOTSUPP; |
| 1702 | |
| 1703 | if (ops->stats) |
| 1704 | memset(ops->stats, 0, sizeof(*ops->stats)); |
| 1705 | |
| 1706 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) |
| 1707 | ret_code = mtd_io_emulated_slc(mtd, from, true, ops); |
| 1708 | else |
| 1709 | ret_code = mtd_read_oob_std(mtd, from, ops); |
| 1710 | |
| 1711 | mtd_update_ecc_stats(mtd, master, &old_stats); |
| 1712 | |
| 1713 | /* |
| 1714 | * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics |
| 1715 | * similar to mtd->_read(), returning a non-negative integer |
| 1716 | * representing max bitflips. In other cases, mtd->_read_oob() may |
| 1717 | * return -EUCLEAN. In all cases, perform similar logic to mtd_read(). |
| 1718 | */ |
| 1719 | if (unlikely(ret_code < 0)) |
| 1720 | return ret_code; |
| 1721 | if (mtd->ecc_strength == 0) |
| 1722 | return 0; /* device lacks ecc */ |
| 1723 | if (ops->stats) |
| 1724 | ops->stats->max_bitflips = ret_code; |
| 1725 | return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0; |
| 1726 | } |
| 1727 | EXPORT_SYMBOL_GPL(mtd_read_oob); |
| 1728 | |
| 1729 | int mtd_write_oob(struct mtd_info *mtd, loff_t to, |
| 1730 | struct mtd_oob_ops *ops) |
| 1731 | { |
| 1732 | struct mtd_info *master = mtd_get_master(mtd); |
| 1733 | int ret; |
| 1734 | |
| 1735 | ops->retlen = ops->oobretlen = 0; |
| 1736 | |
| 1737 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 1738 | return -EROFS; |
| 1739 | |
| 1740 | ret = mtd_check_oob_ops(mtd, to, ops); |
| 1741 | if (ret) |
| 1742 | return ret; |
| 1743 | |
| 1744 | ledtrig_mtd_activity(); |
| 1745 | |
| 1746 | /* Check the validity of a potential fallback on mtd->_write */ |
| 1747 | if (!master->_write_oob && (!master->_write || ops->oobbuf)) |
| 1748 | return -EOPNOTSUPP; |
| 1749 | |
| 1750 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) |
| 1751 | return mtd_io_emulated_slc(mtd, to, false, ops); |
| 1752 | |
| 1753 | return mtd_write_oob_std(mtd, to, ops); |
| 1754 | } |
| 1755 | EXPORT_SYMBOL_GPL(mtd_write_oob); |
| 1756 | |
| 1757 | /** |
| 1758 | * mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section |
| 1759 | * @mtd: MTD device structure |
| 1760 | * @section: ECC section. Depending on the layout you may have all the ECC |
| 1761 | * bytes stored in a single contiguous section, or one section |
| 1762 | * per ECC chunk (and sometime several sections for a single ECC |
| 1763 | * ECC chunk) |
| 1764 | * @oobecc: OOB region struct filled with the appropriate ECC position |
| 1765 | * information |
| 1766 | * |
| 1767 | * This function returns ECC section information in the OOB area. If you want |
| 1768 | * to get all the ECC bytes information, then you should call |
| 1769 | * mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE. |
| 1770 | * |
| 1771 | * Returns zero on success, a negative error code otherwise. |
| 1772 | */ |
| 1773 | int mtd_ooblayout_ecc(struct mtd_info *mtd, int section, |
| 1774 | struct mtd_oob_region *oobecc) |
| 1775 | { |
| 1776 | struct mtd_info *master = mtd_get_master(mtd); |
| 1777 | |
| 1778 | memset(oobecc, 0, sizeof(*oobecc)); |
| 1779 | |
| 1780 | if (!master || section < 0) |
| 1781 | return -EINVAL; |
| 1782 | |
| 1783 | if (!master->ooblayout || !master->ooblayout->ecc) |
| 1784 | return -ENOTSUPP; |
| 1785 | |
| 1786 | return master->ooblayout->ecc(master, section, oobecc); |
| 1787 | } |
| 1788 | EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc); |
| 1789 | |
| 1790 | /** |
| 1791 | * mtd_ooblayout_free - Get the OOB region definition of a specific free |
| 1792 | * section |
| 1793 | * @mtd: MTD device structure |
| 1794 | * @section: Free section you are interested in. Depending on the layout |
| 1795 | * you may have all the free bytes stored in a single contiguous |
| 1796 | * section, or one section per ECC chunk plus an extra section |
| 1797 | * for the remaining bytes (or other funky layout). |
| 1798 | * @oobfree: OOB region struct filled with the appropriate free position |
| 1799 | * information |
| 1800 | * |
| 1801 | * This function returns free bytes position in the OOB area. If you want |
| 1802 | * to get all the free bytes information, then you should call |
| 1803 | * mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE. |
| 1804 | * |
| 1805 | * Returns zero on success, a negative error code otherwise. |
| 1806 | */ |
| 1807 | int mtd_ooblayout_free(struct mtd_info *mtd, int section, |
| 1808 | struct mtd_oob_region *oobfree) |
| 1809 | { |
| 1810 | struct mtd_info *master = mtd_get_master(mtd); |
| 1811 | |
| 1812 | memset(oobfree, 0, sizeof(*oobfree)); |
| 1813 | |
| 1814 | if (!master || section < 0) |
| 1815 | return -EINVAL; |
| 1816 | |
| 1817 | if (!master->ooblayout || !master->ooblayout->free) |
| 1818 | return -ENOTSUPP; |
| 1819 | |
| 1820 | return master->ooblayout->free(master, section, oobfree); |
| 1821 | } |
| 1822 | EXPORT_SYMBOL_GPL(mtd_ooblayout_free); |
| 1823 | |
| 1824 | /** |
| 1825 | * mtd_ooblayout_find_region - Find the region attached to a specific byte |
| 1826 | * @mtd: mtd info structure |
| 1827 | * @byte: the byte we are searching for |
| 1828 | * @sectionp: pointer where the section id will be stored |
| 1829 | * @oobregion: used to retrieve the ECC position |
| 1830 | * @iter: iterator function. Should be either mtd_ooblayout_free or |
| 1831 | * mtd_ooblayout_ecc depending on the region type you're searching for |
| 1832 | * |
| 1833 | * This function returns the section id and oobregion information of a |
| 1834 | * specific byte. For example, say you want to know where the 4th ECC byte is |
| 1835 | * stored, you'll use: |
| 1836 | * |
| 1837 | * mtd_ooblayout_find_region(mtd, 3, §ion, &oobregion, mtd_ooblayout_ecc); |
| 1838 | * |
| 1839 | * Returns zero on success, a negative error code otherwise. |
| 1840 | */ |
| 1841 | static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte, |
| 1842 | int *sectionp, struct mtd_oob_region *oobregion, |
| 1843 | int (*iter)(struct mtd_info *, |
| 1844 | int section, |
| 1845 | struct mtd_oob_region *oobregion)) |
| 1846 | { |
| 1847 | int pos = 0, ret, section = 0; |
| 1848 | |
| 1849 | memset(oobregion, 0, sizeof(*oobregion)); |
| 1850 | |
| 1851 | while (1) { |
| 1852 | ret = iter(mtd, section, oobregion); |
| 1853 | if (ret) |
| 1854 | return ret; |
| 1855 | |
| 1856 | if (pos + oobregion->length > byte) |
| 1857 | break; |
| 1858 | |
| 1859 | pos += oobregion->length; |
| 1860 | section++; |
| 1861 | } |
| 1862 | |
| 1863 | /* |
| 1864 | * Adjust region info to make it start at the beginning at the |
| 1865 | * 'start' ECC byte. |
| 1866 | */ |
| 1867 | oobregion->offset += byte - pos; |
| 1868 | oobregion->length -= byte - pos; |
| 1869 | *sectionp = section; |
| 1870 | |
| 1871 | return 0; |
| 1872 | } |
| 1873 | |
| 1874 | /** |
| 1875 | * mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific |
| 1876 | * ECC byte |
| 1877 | * @mtd: mtd info structure |
| 1878 | * @eccbyte: the byte we are searching for |
| 1879 | * @section: pointer where the section id will be stored |
| 1880 | * @oobregion: OOB region information |
| 1881 | * |
| 1882 | * Works like mtd_ooblayout_find_region() except it searches for a specific ECC |
| 1883 | * byte. |
| 1884 | * |
| 1885 | * Returns zero on success, a negative error code otherwise. |
| 1886 | */ |
| 1887 | int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte, |
| 1888 | int *section, |
| 1889 | struct mtd_oob_region *oobregion) |
| 1890 | { |
| 1891 | return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion, |
| 1892 | mtd_ooblayout_ecc); |
| 1893 | } |
| 1894 | EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion); |
| 1895 | |
| 1896 | /** |
| 1897 | * mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer |
| 1898 | * @mtd: mtd info structure |
| 1899 | * @buf: destination buffer to store OOB bytes |
| 1900 | * @oobbuf: OOB buffer |
| 1901 | * @start: first byte to retrieve |
| 1902 | * @nbytes: number of bytes to retrieve |
| 1903 | * @iter: section iterator |
| 1904 | * |
| 1905 | * Extract bytes attached to a specific category (ECC or free) |
| 1906 | * from the OOB buffer and copy them into buf. |
| 1907 | * |
| 1908 | * Returns zero on success, a negative error code otherwise. |
| 1909 | */ |
| 1910 | static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf, |
| 1911 | const u8 *oobbuf, int start, int nbytes, |
| 1912 | int (*iter)(struct mtd_info *, |
| 1913 | int section, |
| 1914 | struct mtd_oob_region *oobregion)) |
| 1915 | { |
| 1916 | struct mtd_oob_region oobregion; |
| 1917 | int section, ret; |
| 1918 | |
| 1919 | ret = mtd_ooblayout_find_region(mtd, start, §ion, |
| 1920 | &oobregion, iter); |
| 1921 | |
| 1922 | while (!ret) { |
| 1923 | int cnt; |
| 1924 | |
| 1925 | cnt = min_t(int, nbytes, oobregion.length); |
| 1926 | memcpy(buf, oobbuf + oobregion.offset, cnt); |
| 1927 | buf += cnt; |
| 1928 | nbytes -= cnt; |
| 1929 | |
| 1930 | if (!nbytes) |
| 1931 | break; |
| 1932 | |
| 1933 | ret = iter(mtd, ++section, &oobregion); |
| 1934 | } |
| 1935 | |
| 1936 | return ret; |
| 1937 | } |
| 1938 | |
| 1939 | /** |
| 1940 | * mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer |
| 1941 | * @mtd: mtd info structure |
| 1942 | * @buf: source buffer to get OOB bytes from |
| 1943 | * @oobbuf: OOB buffer |
| 1944 | * @start: first OOB byte to set |
| 1945 | * @nbytes: number of OOB bytes to set |
| 1946 | * @iter: section iterator |
| 1947 | * |
| 1948 | * Fill the OOB buffer with data provided in buf. The category (ECC or free) |
| 1949 | * is selected by passing the appropriate iterator. |
| 1950 | * |
| 1951 | * Returns zero on success, a negative error code otherwise. |
| 1952 | */ |
| 1953 | static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf, |
| 1954 | u8 *oobbuf, int start, int nbytes, |
| 1955 | int (*iter)(struct mtd_info *, |
| 1956 | int section, |
| 1957 | struct mtd_oob_region *oobregion)) |
| 1958 | { |
| 1959 | struct mtd_oob_region oobregion; |
| 1960 | int section, ret; |
| 1961 | |
| 1962 | ret = mtd_ooblayout_find_region(mtd, start, §ion, |
| 1963 | &oobregion, iter); |
| 1964 | |
| 1965 | while (!ret) { |
| 1966 | int cnt; |
| 1967 | |
| 1968 | cnt = min_t(int, nbytes, oobregion.length); |
| 1969 | memcpy(oobbuf + oobregion.offset, buf, cnt); |
| 1970 | buf += cnt; |
| 1971 | nbytes -= cnt; |
| 1972 | |
| 1973 | if (!nbytes) |
| 1974 | break; |
| 1975 | |
| 1976 | ret = iter(mtd, ++section, &oobregion); |
| 1977 | } |
| 1978 | |
| 1979 | return ret; |
| 1980 | } |
| 1981 | |
| 1982 | /** |
| 1983 | * mtd_ooblayout_count_bytes - count the number of bytes in a OOB category |
| 1984 | * @mtd: mtd info structure |
| 1985 | * @iter: category iterator |
| 1986 | * |
| 1987 | * Count the number of bytes in a given category. |
| 1988 | * |
| 1989 | * Returns a positive value on success, a negative error code otherwise. |
| 1990 | */ |
| 1991 | static int mtd_ooblayout_count_bytes(struct mtd_info *mtd, |
| 1992 | int (*iter)(struct mtd_info *, |
| 1993 | int section, |
| 1994 | struct mtd_oob_region *oobregion)) |
| 1995 | { |
| 1996 | struct mtd_oob_region oobregion; |
| 1997 | int section = 0, ret, nbytes = 0; |
| 1998 | |
| 1999 | while (1) { |
| 2000 | ret = iter(mtd, section++, &oobregion); |
| 2001 | if (ret) { |
| 2002 | if (ret == -ERANGE) |
| 2003 | ret = nbytes; |
| 2004 | break; |
| 2005 | } |
| 2006 | |
| 2007 | nbytes += oobregion.length; |
| 2008 | } |
| 2009 | |
| 2010 | return ret; |
| 2011 | } |
| 2012 | |
| 2013 | /** |
| 2014 | * mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer |
| 2015 | * @mtd: mtd info structure |
| 2016 | * @eccbuf: destination buffer to store ECC bytes |
| 2017 | * @oobbuf: OOB buffer |
| 2018 | * @start: first ECC byte to retrieve |
| 2019 | * @nbytes: number of ECC bytes to retrieve |
| 2020 | * |
| 2021 | * Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes. |
| 2022 | * |
| 2023 | * Returns zero on success, a negative error code otherwise. |
| 2024 | */ |
| 2025 | int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf, |
| 2026 | const u8 *oobbuf, int start, int nbytes) |
| 2027 | { |
| 2028 | return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes, |
| 2029 | mtd_ooblayout_ecc); |
| 2030 | } |
| 2031 | EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes); |
| 2032 | |
| 2033 | /** |
| 2034 | * mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer |
| 2035 | * @mtd: mtd info structure |
| 2036 | * @eccbuf: source buffer to get ECC bytes from |
| 2037 | * @oobbuf: OOB buffer |
| 2038 | * @start: first ECC byte to set |
| 2039 | * @nbytes: number of ECC bytes to set |
| 2040 | * |
| 2041 | * Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes. |
| 2042 | * |
| 2043 | * Returns zero on success, a negative error code otherwise. |
| 2044 | */ |
| 2045 | int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf, |
| 2046 | u8 *oobbuf, int start, int nbytes) |
| 2047 | { |
| 2048 | return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes, |
| 2049 | mtd_ooblayout_ecc); |
| 2050 | } |
| 2051 | EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes); |
| 2052 | |
| 2053 | /** |
| 2054 | * mtd_ooblayout_get_databytes - extract data bytes from the oob buffer |
| 2055 | * @mtd: mtd info structure |
| 2056 | * @databuf: destination buffer to store ECC bytes |
| 2057 | * @oobbuf: OOB buffer |
| 2058 | * @start: first ECC byte to retrieve |
| 2059 | * @nbytes: number of ECC bytes to retrieve |
| 2060 | * |
| 2061 | * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes. |
| 2062 | * |
| 2063 | * Returns zero on success, a negative error code otherwise. |
| 2064 | */ |
| 2065 | int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf, |
| 2066 | const u8 *oobbuf, int start, int nbytes) |
| 2067 | { |
| 2068 | return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes, |
| 2069 | mtd_ooblayout_free); |
| 2070 | } |
| 2071 | EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes); |
| 2072 | |
| 2073 | /** |
| 2074 | * mtd_ooblayout_set_databytes - set data bytes into the oob buffer |
| 2075 | * @mtd: mtd info structure |
| 2076 | * @databuf: source buffer to get data bytes from |
| 2077 | * @oobbuf: OOB buffer |
| 2078 | * @start: first ECC byte to set |
| 2079 | * @nbytes: number of ECC bytes to set |
| 2080 | * |
| 2081 | * Works like mtd_ooblayout_set_bytes(), except it acts on free bytes. |
| 2082 | * |
| 2083 | * Returns zero on success, a negative error code otherwise. |
| 2084 | */ |
| 2085 | int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf, |
| 2086 | u8 *oobbuf, int start, int nbytes) |
| 2087 | { |
| 2088 | return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes, |
| 2089 | mtd_ooblayout_free); |
| 2090 | } |
| 2091 | EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes); |
| 2092 | |
| 2093 | /** |
| 2094 | * mtd_ooblayout_count_freebytes - count the number of free bytes in OOB |
| 2095 | * @mtd: mtd info structure |
| 2096 | * |
| 2097 | * Works like mtd_ooblayout_count_bytes(), except it count free bytes. |
| 2098 | * |
| 2099 | * Returns zero on success, a negative error code otherwise. |
| 2100 | */ |
| 2101 | int mtd_ooblayout_count_freebytes(struct mtd_info *mtd) |
| 2102 | { |
| 2103 | return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free); |
| 2104 | } |
| 2105 | EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes); |
| 2106 | |
| 2107 | /** |
| 2108 | * mtd_ooblayout_count_eccbytes - count the number of ECC bytes in OOB |
| 2109 | * @mtd: mtd info structure |
| 2110 | * |
| 2111 | * Works like mtd_ooblayout_count_bytes(), except it count ECC bytes. |
| 2112 | * |
| 2113 | * Returns zero on success, a negative error code otherwise. |
| 2114 | */ |
| 2115 | int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd) |
| 2116 | { |
| 2117 | return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc); |
| 2118 | } |
| 2119 | EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes); |
| 2120 | |
| 2121 | /* |
| 2122 | * Method to access the protection register area, present in some flash |
| 2123 | * devices. The user data is one time programmable but the factory data is read |
| 2124 | * only. |
| 2125 | */ |
| 2126 | int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen, |
| 2127 | struct otp_info *buf) |
| 2128 | { |
| 2129 | struct mtd_info *master = mtd_get_master(mtd); |
| 2130 | |
| 2131 | if (!master->_get_fact_prot_info) |
| 2132 | return -EOPNOTSUPP; |
| 2133 | if (!len) |
| 2134 | return 0; |
| 2135 | return master->_get_fact_prot_info(master, len, retlen, buf); |
| 2136 | } |
| 2137 | EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info); |
| 2138 | |
| 2139 | int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len, |
| 2140 | size_t *retlen, u_char *buf) |
| 2141 | { |
| 2142 | struct mtd_info *master = mtd_get_master(mtd); |
| 2143 | |
| 2144 | *retlen = 0; |
| 2145 | if (!master->_read_fact_prot_reg) |
| 2146 | return -EOPNOTSUPP; |
| 2147 | if (!len) |
| 2148 | return 0; |
| 2149 | return master->_read_fact_prot_reg(master, from, len, retlen, buf); |
| 2150 | } |
| 2151 | EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg); |
| 2152 | |
| 2153 | int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen, |
| 2154 | struct otp_info *buf) |
| 2155 | { |
| 2156 | struct mtd_info *master = mtd_get_master(mtd); |
| 2157 | |
| 2158 | if (!master->_get_user_prot_info) |
| 2159 | return -EOPNOTSUPP; |
| 2160 | if (!len) |
| 2161 | return 0; |
| 2162 | return master->_get_user_prot_info(master, len, retlen, buf); |
| 2163 | } |
| 2164 | EXPORT_SYMBOL_GPL(mtd_get_user_prot_info); |
| 2165 | |
| 2166 | int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len, |
| 2167 | size_t *retlen, u_char *buf) |
| 2168 | { |
| 2169 | struct mtd_info *master = mtd_get_master(mtd); |
| 2170 | |
| 2171 | *retlen = 0; |
| 2172 | if (!master->_read_user_prot_reg) |
| 2173 | return -EOPNOTSUPP; |
| 2174 | if (!len) |
| 2175 | return 0; |
| 2176 | return master->_read_user_prot_reg(master, from, len, retlen, buf); |
| 2177 | } |
| 2178 | EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg); |
| 2179 | |
| 2180 | int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len, |
| 2181 | size_t *retlen, const u_char *buf) |
| 2182 | { |
| 2183 | struct mtd_info *master = mtd_get_master(mtd); |
| 2184 | int ret; |
| 2185 | |
| 2186 | *retlen = 0; |
| 2187 | if (!master->_write_user_prot_reg) |
| 2188 | return -EOPNOTSUPP; |
| 2189 | if (!len) |
| 2190 | return 0; |
| 2191 | ret = master->_write_user_prot_reg(master, to, len, retlen, buf); |
| 2192 | if (ret) |
| 2193 | return ret; |
| 2194 | |
| 2195 | /* |
| 2196 | * If no data could be written at all, we are out of memory and |
| 2197 | * must return -ENOSPC. |
| 2198 | */ |
| 2199 | return (*retlen) ? 0 : -ENOSPC; |
| 2200 | } |
| 2201 | EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg); |
| 2202 | |
| 2203 | int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len) |
| 2204 | { |
| 2205 | struct mtd_info *master = mtd_get_master(mtd); |
| 2206 | |
| 2207 | if (!master->_lock_user_prot_reg) |
| 2208 | return -EOPNOTSUPP; |
| 2209 | if (!len) |
| 2210 | return 0; |
| 2211 | return master->_lock_user_prot_reg(master, from, len); |
| 2212 | } |
| 2213 | EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg); |
| 2214 | |
| 2215 | int mtd_erase_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len) |
| 2216 | { |
| 2217 | struct mtd_info *master = mtd_get_master(mtd); |
| 2218 | |
| 2219 | if (!master->_erase_user_prot_reg) |
| 2220 | return -EOPNOTSUPP; |
| 2221 | if (!len) |
| 2222 | return 0; |
| 2223 | return master->_erase_user_prot_reg(master, from, len); |
| 2224 | } |
| 2225 | EXPORT_SYMBOL_GPL(mtd_erase_user_prot_reg); |
| 2226 | |
| 2227 | /* Chip-supported device locking */ |
| 2228 | int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len) |
| 2229 | { |
| 2230 | struct mtd_info *master = mtd_get_master(mtd); |
| 2231 | |
| 2232 | if (!master->_lock) |
| 2233 | return -EOPNOTSUPP; |
| 2234 | if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs) |
| 2235 | return -EINVAL; |
| 2236 | if (!len) |
| 2237 | return 0; |
| 2238 | |
| 2239 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 2240 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2241 | len = (u64)mtd_div_by_eb(len, mtd) * master->erasesize; |
| 2242 | } |
| 2243 | |
| 2244 | return master->_lock(master, mtd_get_master_ofs(mtd, ofs), len); |
| 2245 | } |
| 2246 | EXPORT_SYMBOL_GPL(mtd_lock); |
| 2247 | |
| 2248 | int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len) |
| 2249 | { |
| 2250 | struct mtd_info *master = mtd_get_master(mtd); |
| 2251 | |
| 2252 | if (!master->_unlock) |
| 2253 | return -EOPNOTSUPP; |
| 2254 | if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs) |
| 2255 | return -EINVAL; |
| 2256 | if (!len) |
| 2257 | return 0; |
| 2258 | |
| 2259 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 2260 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2261 | len = (u64)mtd_div_by_eb(len, mtd) * master->erasesize; |
| 2262 | } |
| 2263 | |
| 2264 | return master->_unlock(master, mtd_get_master_ofs(mtd, ofs), len); |
| 2265 | } |
| 2266 | EXPORT_SYMBOL_GPL(mtd_unlock); |
| 2267 | |
| 2268 | int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len) |
| 2269 | { |
| 2270 | struct mtd_info *master = mtd_get_master(mtd); |
| 2271 | |
| 2272 | if (!master->_is_locked) |
| 2273 | return -EOPNOTSUPP; |
| 2274 | if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs) |
| 2275 | return -EINVAL; |
| 2276 | if (!len) |
| 2277 | return 0; |
| 2278 | |
| 2279 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) { |
| 2280 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2281 | len = (u64)mtd_div_by_eb(len, mtd) * master->erasesize; |
| 2282 | } |
| 2283 | |
| 2284 | return master->_is_locked(master, mtd_get_master_ofs(mtd, ofs), len); |
| 2285 | } |
| 2286 | EXPORT_SYMBOL_GPL(mtd_is_locked); |
| 2287 | |
| 2288 | int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs) |
| 2289 | { |
| 2290 | struct mtd_info *master = mtd_get_master(mtd); |
| 2291 | |
| 2292 | if (ofs < 0 || ofs >= mtd->size) |
| 2293 | return -EINVAL; |
| 2294 | if (!master->_block_isreserved) |
| 2295 | return 0; |
| 2296 | |
| 2297 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) |
| 2298 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2299 | |
| 2300 | return master->_block_isreserved(master, mtd_get_master_ofs(mtd, ofs)); |
| 2301 | } |
| 2302 | EXPORT_SYMBOL_GPL(mtd_block_isreserved); |
| 2303 | |
| 2304 | int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs) |
| 2305 | { |
| 2306 | struct mtd_info *master = mtd_get_master(mtd); |
| 2307 | |
| 2308 | if (ofs < 0 || ofs >= mtd->size) |
| 2309 | return -EINVAL; |
| 2310 | if (!master->_block_isbad) |
| 2311 | return 0; |
| 2312 | |
| 2313 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) |
| 2314 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2315 | |
| 2316 | return master->_block_isbad(master, mtd_get_master_ofs(mtd, ofs)); |
| 2317 | } |
| 2318 | EXPORT_SYMBOL_GPL(mtd_block_isbad); |
| 2319 | |
| 2320 | int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs) |
| 2321 | { |
| 2322 | struct mtd_info *master = mtd_get_master(mtd); |
| 2323 | int ret; |
| 2324 | |
| 2325 | if (!master->_block_markbad) |
| 2326 | return -EOPNOTSUPP; |
| 2327 | if (ofs < 0 || ofs >= mtd->size) |
| 2328 | return -EINVAL; |
| 2329 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 2330 | return -EROFS; |
| 2331 | |
| 2332 | if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) |
| 2333 | ofs = (loff_t)mtd_div_by_eb(ofs, mtd) * master->erasesize; |
| 2334 | |
| 2335 | ret = master->_block_markbad(master, mtd_get_master_ofs(mtd, ofs)); |
| 2336 | if (ret) |
| 2337 | return ret; |
| 2338 | |
| 2339 | while (mtd->parent) { |
| 2340 | mtd->ecc_stats.badblocks++; |
| 2341 | mtd = mtd->parent; |
| 2342 | } |
| 2343 | |
| 2344 | return 0; |
| 2345 | } |
| 2346 | EXPORT_SYMBOL_GPL(mtd_block_markbad); |
| 2347 | |
| 2348 | /* |
| 2349 | * default_mtd_writev - the default writev method |
| 2350 | * @mtd: mtd device description object pointer |
| 2351 | * @vecs: the vectors to write |
| 2352 | * @count: count of vectors in @vecs |
| 2353 | * @to: the MTD device offset to write to |
| 2354 | * @retlen: on exit contains the count of bytes written to the MTD device. |
| 2355 | * |
| 2356 | * This function returns zero in case of success and a negative error code in |
| 2357 | * case of failure. |
| 2358 | */ |
| 2359 | static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, |
| 2360 | unsigned long count, loff_t to, size_t *retlen) |
| 2361 | { |
| 2362 | unsigned long i; |
| 2363 | size_t totlen = 0, thislen; |
| 2364 | int ret = 0; |
| 2365 | |
| 2366 | for (i = 0; i < count; i++) { |
| 2367 | if (!vecs[i].iov_len) |
| 2368 | continue; |
| 2369 | ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen, |
| 2370 | vecs[i].iov_base); |
| 2371 | totlen += thislen; |
| 2372 | if (ret || thislen != vecs[i].iov_len) |
| 2373 | break; |
| 2374 | to += vecs[i].iov_len; |
| 2375 | } |
| 2376 | *retlen = totlen; |
| 2377 | return ret; |
| 2378 | } |
| 2379 | |
| 2380 | /* |
| 2381 | * mtd_writev - the vector-based MTD write method |
| 2382 | * @mtd: mtd device description object pointer |
| 2383 | * @vecs: the vectors to write |
| 2384 | * @count: count of vectors in @vecs |
| 2385 | * @to: the MTD device offset to write to |
| 2386 | * @retlen: on exit contains the count of bytes written to the MTD device. |
| 2387 | * |
| 2388 | * This function returns zero in case of success and a negative error code in |
| 2389 | * case of failure. |
| 2390 | */ |
| 2391 | int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, |
| 2392 | unsigned long count, loff_t to, size_t *retlen) |
| 2393 | { |
| 2394 | struct mtd_info *master = mtd_get_master(mtd); |
| 2395 | |
| 2396 | *retlen = 0; |
| 2397 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 2398 | return -EROFS; |
| 2399 | |
| 2400 | if (!master->_writev) |
| 2401 | return default_mtd_writev(mtd, vecs, count, to, retlen); |
| 2402 | |
| 2403 | return master->_writev(master, vecs, count, |
| 2404 | mtd_get_master_ofs(mtd, to), retlen); |
| 2405 | } |
| 2406 | EXPORT_SYMBOL_GPL(mtd_writev); |
| 2407 | |
| 2408 | /** |
| 2409 | * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size |
| 2410 | * @mtd: mtd device description object pointer |
| 2411 | * @size: a pointer to the ideal or maximum size of the allocation, points |
| 2412 | * to the actual allocation size on success. |
| 2413 | * |
| 2414 | * This routine attempts to allocate a contiguous kernel buffer up to |
| 2415 | * the specified size, backing off the size of the request exponentially |
| 2416 | * until the request succeeds or until the allocation size falls below |
| 2417 | * the system page size. This attempts to make sure it does not adversely |
| 2418 | * impact system performance, so when allocating more than one page, we |
| 2419 | * ask the memory allocator to avoid re-trying, swapping, writing back |
| 2420 | * or performing I/O. |
| 2421 | * |
| 2422 | * Note, this function also makes sure that the allocated buffer is aligned to |
| 2423 | * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value. |
| 2424 | * |
| 2425 | * This is called, for example by mtd_{read,write} and jffs2_scan_medium, |
| 2426 | * to handle smaller (i.e. degraded) buffer allocations under low- or |
| 2427 | * fragmented-memory situations where such reduced allocations, from a |
| 2428 | * requested ideal, are allowed. |
| 2429 | * |
| 2430 | * Returns a pointer to the allocated buffer on success; otherwise, NULL. |
| 2431 | */ |
| 2432 | void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size) |
| 2433 | { |
| 2434 | gfp_t flags = __GFP_NOWARN | __GFP_DIRECT_RECLAIM | __GFP_NORETRY; |
| 2435 | size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE); |
| 2436 | void *kbuf; |
| 2437 | |
| 2438 | *size = min_t(size_t, *size, KMALLOC_MAX_SIZE); |
| 2439 | |
| 2440 | while (*size > min_alloc) { |
| 2441 | kbuf = kmalloc(*size, flags); |
| 2442 | if (kbuf) |
| 2443 | return kbuf; |
| 2444 | |
| 2445 | *size >>= 1; |
| 2446 | *size = ALIGN(*size, mtd->writesize); |
| 2447 | } |
| 2448 | |
| 2449 | /* |
| 2450 | * For the last resort allocation allow 'kmalloc()' to do all sorts of |
| 2451 | * things (write-back, dropping caches, etc) by using GFP_KERNEL. |
| 2452 | */ |
| 2453 | return kmalloc(*size, GFP_KERNEL); |
| 2454 | } |
| 2455 | EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to); |
| 2456 | |
| 2457 | #ifdef CONFIG_PROC_FS |
| 2458 | |
| 2459 | /*====================================================================*/ |
| 2460 | /* Support for /proc/mtd */ |
| 2461 | |
| 2462 | static int mtd_proc_show(struct seq_file *m, void *v) |
| 2463 | { |
| 2464 | struct mtd_info *mtd; |
| 2465 | |
| 2466 | seq_puts(m, "dev: size erasesize name\n"); |
| 2467 | mutex_lock(&mtd_table_mutex); |
| 2468 | mtd_for_each_device(mtd) { |
| 2469 | seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n", |
| 2470 | mtd->index, (unsigned long long)mtd->size, |
| 2471 | mtd->erasesize, mtd->name); |
| 2472 | } |
| 2473 | mutex_unlock(&mtd_table_mutex); |
| 2474 | return 0; |
| 2475 | } |
| 2476 | #endif /* CONFIG_PROC_FS */ |
| 2477 | |
| 2478 | /*====================================================================*/ |
| 2479 | /* Init code */ |
| 2480 | |
| 2481 | static struct backing_dev_info * __init mtd_bdi_init(const char *name) |
| 2482 | { |
| 2483 | struct backing_dev_info *bdi; |
| 2484 | int ret; |
| 2485 | |
| 2486 | bdi = bdi_alloc(NUMA_NO_NODE); |
| 2487 | if (!bdi) |
| 2488 | return ERR_PTR(-ENOMEM); |
| 2489 | bdi->ra_pages = 0; |
| 2490 | bdi->io_pages = 0; |
| 2491 | |
| 2492 | /* |
| 2493 | * We put '-0' suffix to the name to get the same name format as we |
| 2494 | * used to get. Since this is called only once, we get a unique name. |
| 2495 | */ |
| 2496 | ret = bdi_register(bdi, "%.28s-0", name); |
| 2497 | if (ret) |
| 2498 | bdi_put(bdi); |
| 2499 | |
| 2500 | return ret ? ERR_PTR(ret) : bdi; |
| 2501 | } |
| 2502 | |
| 2503 | static struct proc_dir_entry *proc_mtd; |
| 2504 | |
| 2505 | static int __init init_mtd(void) |
| 2506 | { |
| 2507 | int ret; |
| 2508 | |
| 2509 | ret = class_register(&mtd_class); |
| 2510 | if (ret) |
| 2511 | goto err_reg; |
| 2512 | |
| 2513 | mtd_bdi = mtd_bdi_init("mtd"); |
| 2514 | if (IS_ERR(mtd_bdi)) { |
| 2515 | ret = PTR_ERR(mtd_bdi); |
| 2516 | goto err_bdi; |
| 2517 | } |
| 2518 | |
| 2519 | proc_mtd = proc_create_single("mtd", 0, NULL, mtd_proc_show); |
| 2520 | |
| 2521 | ret = init_mtdchar(); |
| 2522 | if (ret) |
| 2523 | goto out_procfs; |
| 2524 | |
| 2525 | dfs_dir_mtd = debugfs_create_dir("mtd", NULL); |
| 2526 | debugfs_create_bool("expert_analysis_mode", 0600, dfs_dir_mtd, |
| 2527 | &mtd_expert_analysis_mode); |
| 2528 | |
| 2529 | return 0; |
| 2530 | |
| 2531 | out_procfs: |
| 2532 | if (proc_mtd) |
| 2533 | remove_proc_entry("mtd", NULL); |
| 2534 | bdi_unregister(mtd_bdi); |
| 2535 | bdi_put(mtd_bdi); |
| 2536 | err_bdi: |
| 2537 | class_unregister(&mtd_class); |
| 2538 | err_reg: |
| 2539 | pr_err("Error registering mtd class or bdi: %d\n", ret); |
| 2540 | return ret; |
| 2541 | } |
| 2542 | |
| 2543 | static void __exit cleanup_mtd(void) |
| 2544 | { |
| 2545 | debugfs_remove_recursive(dfs_dir_mtd); |
| 2546 | cleanup_mtdchar(); |
| 2547 | if (proc_mtd) |
| 2548 | remove_proc_entry("mtd", NULL); |
| 2549 | class_unregister(&mtd_class); |
| 2550 | bdi_unregister(mtd_bdi); |
| 2551 | bdi_put(mtd_bdi); |
| 2552 | idr_destroy(&mtd_idr); |
| 2553 | } |
| 2554 | |
| 2555 | module_init(init_mtd); |
| 2556 | module_exit(cleanup_mtd); |
| 2557 | |
| 2558 | MODULE_LICENSE("GPL"); |
| 2559 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); |
| 2560 | MODULE_DESCRIPTION("Core MTD registration and access routines"); |