| 1 | /* |
| 2 | * Copyright (C) 2008 Advanced Micro Devices, Inc. |
| 3 | * |
| 4 | * Author: Joerg Roedel <joerg.roedel@amd.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published |
| 8 | * by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 18 | */ |
| 19 | |
| 20 | #include <linux/scatterlist.h> |
| 21 | #include <linux/dma-mapping.h> |
| 22 | #include <linux/stacktrace.h> |
| 23 | #include <linux/dma-debug.h> |
| 24 | #include <linux/spinlock.h> |
| 25 | #include <linux/debugfs.h> |
| 26 | #include <linux/uaccess.h> |
| 27 | #include <linux/export.h> |
| 28 | #include <linux/device.h> |
| 29 | #include <linux/types.h> |
| 30 | #include <linux/sched.h> |
| 31 | #include <linux/ctype.h> |
| 32 | #include <linux/list.h> |
| 33 | #include <linux/slab.h> |
| 34 | |
| 35 | #include <asm/sections.h> |
| 36 | |
| 37 | #define HASH_SIZE 1024ULL |
| 38 | #define HASH_FN_SHIFT 13 |
| 39 | #define HASH_FN_MASK (HASH_SIZE - 1) |
| 40 | |
| 41 | enum { |
| 42 | dma_debug_single, |
| 43 | dma_debug_page, |
| 44 | dma_debug_sg, |
| 45 | dma_debug_coherent, |
| 46 | }; |
| 47 | |
| 48 | enum map_err_types { |
| 49 | MAP_ERR_CHECK_NOT_APPLICABLE, |
| 50 | MAP_ERR_NOT_CHECKED, |
| 51 | MAP_ERR_CHECKED, |
| 52 | }; |
| 53 | |
| 54 | #define DMA_DEBUG_STACKTRACE_ENTRIES 5 |
| 55 | |
| 56 | struct dma_debug_entry { |
| 57 | struct list_head list; |
| 58 | struct device *dev; |
| 59 | int type; |
| 60 | phys_addr_t paddr; |
| 61 | u64 dev_addr; |
| 62 | u64 size; |
| 63 | int direction; |
| 64 | int sg_call_ents; |
| 65 | int sg_mapped_ents; |
| 66 | enum map_err_types map_err_type; |
| 67 | #ifdef CONFIG_STACKTRACE |
| 68 | struct stack_trace stacktrace; |
| 69 | unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; |
| 70 | #endif |
| 71 | }; |
| 72 | |
| 73 | typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *); |
| 74 | |
| 75 | struct hash_bucket { |
| 76 | struct list_head list; |
| 77 | spinlock_t lock; |
| 78 | } ____cacheline_aligned_in_smp; |
| 79 | |
| 80 | /* Hash list to save the allocated dma addresses */ |
| 81 | static struct hash_bucket dma_entry_hash[HASH_SIZE]; |
| 82 | /* List of pre-allocated dma_debug_entry's */ |
| 83 | static LIST_HEAD(free_entries); |
| 84 | /* Lock for the list above */ |
| 85 | static DEFINE_SPINLOCK(free_entries_lock); |
| 86 | |
| 87 | /* Global disable flag - will be set in case of an error */ |
| 88 | static u32 global_disable __read_mostly; |
| 89 | |
| 90 | /* Global error count */ |
| 91 | static u32 error_count; |
| 92 | |
| 93 | /* Global error show enable*/ |
| 94 | static u32 show_all_errors __read_mostly; |
| 95 | /* Number of errors to show */ |
| 96 | static u32 show_num_errors = 1; |
| 97 | |
| 98 | static u32 num_free_entries; |
| 99 | static u32 min_free_entries; |
| 100 | static u32 nr_total_entries; |
| 101 | |
| 102 | /* number of preallocated entries requested by kernel cmdline */ |
| 103 | static u32 req_entries; |
| 104 | |
| 105 | /* debugfs dentry's for the stuff above */ |
| 106 | static struct dentry *dma_debug_dent __read_mostly; |
| 107 | static struct dentry *global_disable_dent __read_mostly; |
| 108 | static struct dentry *error_count_dent __read_mostly; |
| 109 | static struct dentry *show_all_errors_dent __read_mostly; |
| 110 | static struct dentry *show_num_errors_dent __read_mostly; |
| 111 | static struct dentry *num_free_entries_dent __read_mostly; |
| 112 | static struct dentry *min_free_entries_dent __read_mostly; |
| 113 | static struct dentry *filter_dent __read_mostly; |
| 114 | |
| 115 | /* per-driver filter related state */ |
| 116 | |
| 117 | #define NAME_MAX_LEN 64 |
| 118 | |
| 119 | static char current_driver_name[NAME_MAX_LEN] __read_mostly; |
| 120 | static struct device_driver *current_driver __read_mostly; |
| 121 | |
| 122 | static DEFINE_RWLOCK(driver_name_lock); |
| 123 | |
| 124 | static const char *const maperr2str[] = { |
| 125 | [MAP_ERR_CHECK_NOT_APPLICABLE] = "dma map error check not applicable", |
| 126 | [MAP_ERR_NOT_CHECKED] = "dma map error not checked", |
| 127 | [MAP_ERR_CHECKED] = "dma map error checked", |
| 128 | }; |
| 129 | |
| 130 | static const char *type2name[4] = { "single", "page", |
| 131 | "scather-gather", "coherent" }; |
| 132 | |
| 133 | static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", |
| 134 | "DMA_FROM_DEVICE", "DMA_NONE" }; |
| 135 | |
| 136 | /* |
| 137 | * The access to some variables in this macro is racy. We can't use atomic_t |
| 138 | * here because all these variables are exported to debugfs. Some of them even |
| 139 | * writeable. This is also the reason why a lock won't help much. But anyway, |
| 140 | * the races are no big deal. Here is why: |
| 141 | * |
| 142 | * error_count: the addition is racy, but the worst thing that can happen is |
| 143 | * that we don't count some errors |
| 144 | * show_num_errors: the subtraction is racy. Also no big deal because in |
| 145 | * worst case this will result in one warning more in the |
| 146 | * system log than the user configured. This variable is |
| 147 | * writeable via debugfs. |
| 148 | */ |
| 149 | static inline void dump_entry_trace(struct dma_debug_entry *entry) |
| 150 | { |
| 151 | #ifdef CONFIG_STACKTRACE |
| 152 | if (entry) { |
| 153 | pr_warning("Mapped at:\n"); |
| 154 | print_stack_trace(&entry->stacktrace, 0); |
| 155 | } |
| 156 | #endif |
| 157 | } |
| 158 | |
| 159 | static bool driver_filter(struct device *dev) |
| 160 | { |
| 161 | struct device_driver *drv; |
| 162 | unsigned long flags; |
| 163 | bool ret; |
| 164 | |
| 165 | /* driver filter off */ |
| 166 | if (likely(!current_driver_name[0])) |
| 167 | return true; |
| 168 | |
| 169 | /* driver filter on and initialized */ |
| 170 | if (current_driver && dev && dev->driver == current_driver) |
| 171 | return true; |
| 172 | |
| 173 | /* driver filter on, but we can't filter on a NULL device... */ |
| 174 | if (!dev) |
| 175 | return false; |
| 176 | |
| 177 | if (current_driver || !current_driver_name[0]) |
| 178 | return false; |
| 179 | |
| 180 | /* driver filter on but not yet initialized */ |
| 181 | drv = dev->driver; |
| 182 | if (!drv) |
| 183 | return false; |
| 184 | |
| 185 | /* lock to protect against change of current_driver_name */ |
| 186 | read_lock_irqsave(&driver_name_lock, flags); |
| 187 | |
| 188 | ret = false; |
| 189 | if (drv->name && |
| 190 | strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) { |
| 191 | current_driver = drv; |
| 192 | ret = true; |
| 193 | } |
| 194 | |
| 195 | read_unlock_irqrestore(&driver_name_lock, flags); |
| 196 | |
| 197 | return ret; |
| 198 | } |
| 199 | |
| 200 | #define err_printk(dev, entry, format, arg...) do { \ |
| 201 | error_count += 1; \ |
| 202 | if (driver_filter(dev) && \ |
| 203 | (show_all_errors || show_num_errors > 0)) { \ |
| 204 | WARN(1, "%s %s: " format, \ |
| 205 | dev ? dev_driver_string(dev) : "NULL", \ |
| 206 | dev ? dev_name(dev) : "NULL", ## arg); \ |
| 207 | dump_entry_trace(entry); \ |
| 208 | } \ |
| 209 | if (!show_all_errors && show_num_errors > 0) \ |
| 210 | show_num_errors -= 1; \ |
| 211 | } while (0); |
| 212 | |
| 213 | /* |
| 214 | * Hash related functions |
| 215 | * |
| 216 | * Every DMA-API request is saved into a struct dma_debug_entry. To |
| 217 | * have quick access to these structs they are stored into a hash. |
| 218 | */ |
| 219 | static int hash_fn(struct dma_debug_entry *entry) |
| 220 | { |
| 221 | /* |
| 222 | * Hash function is based on the dma address. |
| 223 | * We use bits 20-27 here as the index into the hash |
| 224 | */ |
| 225 | return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK; |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * Request exclusive access to a hash bucket for a given dma_debug_entry. |
| 230 | */ |
| 231 | static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry, |
| 232 | unsigned long *flags) |
| 233 | { |
| 234 | int idx = hash_fn(entry); |
| 235 | unsigned long __flags; |
| 236 | |
| 237 | spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags); |
| 238 | *flags = __flags; |
| 239 | return &dma_entry_hash[idx]; |
| 240 | } |
| 241 | |
| 242 | /* |
| 243 | * Give up exclusive access to the hash bucket |
| 244 | */ |
| 245 | static void put_hash_bucket(struct hash_bucket *bucket, |
| 246 | unsigned long *flags) |
| 247 | { |
| 248 | unsigned long __flags = *flags; |
| 249 | |
| 250 | spin_unlock_irqrestore(&bucket->lock, __flags); |
| 251 | } |
| 252 | |
| 253 | static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b) |
| 254 | { |
| 255 | return ((a->dev_addr == b->dev_addr) && |
| 256 | (a->dev == b->dev)) ? true : false; |
| 257 | } |
| 258 | |
| 259 | static bool containing_match(struct dma_debug_entry *a, |
| 260 | struct dma_debug_entry *b) |
| 261 | { |
| 262 | if (a->dev != b->dev) |
| 263 | return false; |
| 264 | |
| 265 | if ((b->dev_addr <= a->dev_addr) && |
| 266 | ((b->dev_addr + b->size) >= (a->dev_addr + a->size))) |
| 267 | return true; |
| 268 | |
| 269 | return false; |
| 270 | } |
| 271 | |
| 272 | /* |
| 273 | * Search a given entry in the hash bucket list |
| 274 | */ |
| 275 | static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket, |
| 276 | struct dma_debug_entry *ref, |
| 277 | match_fn match) |
| 278 | { |
| 279 | struct dma_debug_entry *entry, *ret = NULL; |
| 280 | int matches = 0, match_lvl, last_lvl = -1; |
| 281 | |
| 282 | list_for_each_entry(entry, &bucket->list, list) { |
| 283 | if (!match(ref, entry)) |
| 284 | continue; |
| 285 | |
| 286 | /* |
| 287 | * Some drivers map the same physical address multiple |
| 288 | * times. Without a hardware IOMMU this results in the |
| 289 | * same device addresses being put into the dma-debug |
| 290 | * hash multiple times too. This can result in false |
| 291 | * positives being reported. Therefore we implement a |
| 292 | * best-fit algorithm here which returns the entry from |
| 293 | * the hash which fits best to the reference value |
| 294 | * instead of the first-fit. |
| 295 | */ |
| 296 | matches += 1; |
| 297 | match_lvl = 0; |
| 298 | entry->size == ref->size ? ++match_lvl : 0; |
| 299 | entry->type == ref->type ? ++match_lvl : 0; |
| 300 | entry->direction == ref->direction ? ++match_lvl : 0; |
| 301 | entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0; |
| 302 | |
| 303 | if (match_lvl == 4) { |
| 304 | /* perfect-fit - return the result */ |
| 305 | return entry; |
| 306 | } else if (match_lvl > last_lvl) { |
| 307 | /* |
| 308 | * We found an entry that fits better then the |
| 309 | * previous one or it is the 1st match. |
| 310 | */ |
| 311 | last_lvl = match_lvl; |
| 312 | ret = entry; |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | /* |
| 317 | * If we have multiple matches but no perfect-fit, just return |
| 318 | * NULL. |
| 319 | */ |
| 320 | ret = (matches == 1) ? ret : NULL; |
| 321 | |
| 322 | return ret; |
| 323 | } |
| 324 | |
| 325 | static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket, |
| 326 | struct dma_debug_entry *ref) |
| 327 | { |
| 328 | return __hash_bucket_find(bucket, ref, exact_match); |
| 329 | } |
| 330 | |
| 331 | static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket, |
| 332 | struct dma_debug_entry *ref, |
| 333 | unsigned long *flags) |
| 334 | { |
| 335 | |
| 336 | unsigned int max_range = dma_get_max_seg_size(ref->dev); |
| 337 | struct dma_debug_entry *entry, index = *ref; |
| 338 | unsigned int range = 0; |
| 339 | |
| 340 | while (range <= max_range) { |
| 341 | entry = __hash_bucket_find(*bucket, &index, containing_match); |
| 342 | |
| 343 | if (entry) |
| 344 | return entry; |
| 345 | |
| 346 | /* |
| 347 | * Nothing found, go back a hash bucket |
| 348 | */ |
| 349 | put_hash_bucket(*bucket, flags); |
| 350 | range += (1 << HASH_FN_SHIFT); |
| 351 | index.dev_addr -= (1 << HASH_FN_SHIFT); |
| 352 | *bucket = get_hash_bucket(&index, flags); |
| 353 | } |
| 354 | |
| 355 | return NULL; |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * Add an entry to a hash bucket |
| 360 | */ |
| 361 | static void hash_bucket_add(struct hash_bucket *bucket, |
| 362 | struct dma_debug_entry *entry) |
| 363 | { |
| 364 | list_add_tail(&entry->list, &bucket->list); |
| 365 | } |
| 366 | |
| 367 | /* |
| 368 | * Remove entry from a hash bucket list |
| 369 | */ |
| 370 | static void hash_bucket_del(struct dma_debug_entry *entry) |
| 371 | { |
| 372 | list_del(&entry->list); |
| 373 | } |
| 374 | |
| 375 | /* |
| 376 | * Dump mapping entries for debugging purposes |
| 377 | */ |
| 378 | void debug_dma_dump_mappings(struct device *dev) |
| 379 | { |
| 380 | int idx; |
| 381 | |
| 382 | for (idx = 0; idx < HASH_SIZE; idx++) { |
| 383 | struct hash_bucket *bucket = &dma_entry_hash[idx]; |
| 384 | struct dma_debug_entry *entry; |
| 385 | unsigned long flags; |
| 386 | |
| 387 | spin_lock_irqsave(&bucket->lock, flags); |
| 388 | |
| 389 | list_for_each_entry(entry, &bucket->list, list) { |
| 390 | if (!dev || dev == entry->dev) { |
| 391 | dev_info(entry->dev, |
| 392 | "%s idx %d P=%Lx D=%Lx L=%Lx %s %s\n", |
| 393 | type2name[entry->type], idx, |
| 394 | (unsigned long long)entry->paddr, |
| 395 | entry->dev_addr, entry->size, |
| 396 | dir2name[entry->direction], |
| 397 | maperr2str[entry->map_err_type]); |
| 398 | } |
| 399 | } |
| 400 | |
| 401 | spin_unlock_irqrestore(&bucket->lock, flags); |
| 402 | } |
| 403 | } |
| 404 | EXPORT_SYMBOL(debug_dma_dump_mappings); |
| 405 | |
| 406 | /* |
| 407 | * Wrapper function for adding an entry to the hash. |
| 408 | * This function takes care of locking itself. |
| 409 | */ |
| 410 | static void add_dma_entry(struct dma_debug_entry *entry) |
| 411 | { |
| 412 | struct hash_bucket *bucket; |
| 413 | unsigned long flags; |
| 414 | |
| 415 | bucket = get_hash_bucket(entry, &flags); |
| 416 | hash_bucket_add(bucket, entry); |
| 417 | put_hash_bucket(bucket, &flags); |
| 418 | } |
| 419 | |
| 420 | static struct dma_debug_entry *__dma_entry_alloc(void) |
| 421 | { |
| 422 | struct dma_debug_entry *entry; |
| 423 | |
| 424 | entry = list_entry(free_entries.next, struct dma_debug_entry, list); |
| 425 | list_del(&entry->list); |
| 426 | memset(entry, 0, sizeof(*entry)); |
| 427 | |
| 428 | num_free_entries -= 1; |
| 429 | if (num_free_entries < min_free_entries) |
| 430 | min_free_entries = num_free_entries; |
| 431 | |
| 432 | return entry; |
| 433 | } |
| 434 | |
| 435 | /* struct dma_entry allocator |
| 436 | * |
| 437 | * The next two functions implement the allocator for |
| 438 | * struct dma_debug_entries. |
| 439 | */ |
| 440 | static struct dma_debug_entry *dma_entry_alloc(void) |
| 441 | { |
| 442 | struct dma_debug_entry *entry; |
| 443 | unsigned long flags; |
| 444 | |
| 445 | spin_lock_irqsave(&free_entries_lock, flags); |
| 446 | |
| 447 | if (list_empty(&free_entries)) { |
| 448 | pr_err("DMA-API: debugging out of memory - disabling\n"); |
| 449 | global_disable = true; |
| 450 | spin_unlock_irqrestore(&free_entries_lock, flags); |
| 451 | return NULL; |
| 452 | } |
| 453 | |
| 454 | entry = __dma_entry_alloc(); |
| 455 | |
| 456 | spin_unlock_irqrestore(&free_entries_lock, flags); |
| 457 | |
| 458 | #ifdef CONFIG_STACKTRACE |
| 459 | entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; |
| 460 | entry->stacktrace.entries = entry->st_entries; |
| 461 | entry->stacktrace.skip = 2; |
| 462 | save_stack_trace(&entry->stacktrace); |
| 463 | #endif |
| 464 | |
| 465 | return entry; |
| 466 | } |
| 467 | |
| 468 | static void dma_entry_free(struct dma_debug_entry *entry) |
| 469 | { |
| 470 | unsigned long flags; |
| 471 | |
| 472 | /* |
| 473 | * add to beginning of the list - this way the entries are |
| 474 | * more likely cache hot when they are reallocated. |
| 475 | */ |
| 476 | spin_lock_irqsave(&free_entries_lock, flags); |
| 477 | list_add(&entry->list, &free_entries); |
| 478 | num_free_entries += 1; |
| 479 | spin_unlock_irqrestore(&free_entries_lock, flags); |
| 480 | } |
| 481 | |
| 482 | int dma_debug_resize_entries(u32 num_entries) |
| 483 | { |
| 484 | int i, delta, ret = 0; |
| 485 | unsigned long flags; |
| 486 | struct dma_debug_entry *entry; |
| 487 | LIST_HEAD(tmp); |
| 488 | |
| 489 | spin_lock_irqsave(&free_entries_lock, flags); |
| 490 | |
| 491 | if (nr_total_entries < num_entries) { |
| 492 | delta = num_entries - nr_total_entries; |
| 493 | |
| 494 | spin_unlock_irqrestore(&free_entries_lock, flags); |
| 495 | |
| 496 | for (i = 0; i < delta; i++) { |
| 497 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); |
| 498 | if (!entry) |
| 499 | break; |
| 500 | |
| 501 | list_add_tail(&entry->list, &tmp); |
| 502 | } |
| 503 | |
| 504 | spin_lock_irqsave(&free_entries_lock, flags); |
| 505 | |
| 506 | list_splice(&tmp, &free_entries); |
| 507 | nr_total_entries += i; |
| 508 | num_free_entries += i; |
| 509 | } else { |
| 510 | delta = nr_total_entries - num_entries; |
| 511 | |
| 512 | for (i = 0; i < delta && !list_empty(&free_entries); i++) { |
| 513 | entry = __dma_entry_alloc(); |
| 514 | kfree(entry); |
| 515 | } |
| 516 | |
| 517 | nr_total_entries -= i; |
| 518 | } |
| 519 | |
| 520 | if (nr_total_entries != num_entries) |
| 521 | ret = 1; |
| 522 | |
| 523 | spin_unlock_irqrestore(&free_entries_lock, flags); |
| 524 | |
| 525 | return ret; |
| 526 | } |
| 527 | EXPORT_SYMBOL(dma_debug_resize_entries); |
| 528 | |
| 529 | /* |
| 530 | * DMA-API debugging init code |
| 531 | * |
| 532 | * The init code does two things: |
| 533 | * 1. Initialize core data structures |
| 534 | * 2. Preallocate a given number of dma_debug_entry structs |
| 535 | */ |
| 536 | |
| 537 | static int prealloc_memory(u32 num_entries) |
| 538 | { |
| 539 | struct dma_debug_entry *entry, *next_entry; |
| 540 | int i; |
| 541 | |
| 542 | for (i = 0; i < num_entries; ++i) { |
| 543 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); |
| 544 | if (!entry) |
| 545 | goto out_err; |
| 546 | |
| 547 | list_add_tail(&entry->list, &free_entries); |
| 548 | } |
| 549 | |
| 550 | num_free_entries = num_entries; |
| 551 | min_free_entries = num_entries; |
| 552 | |
| 553 | pr_info("DMA-API: preallocated %d debug entries\n", num_entries); |
| 554 | |
| 555 | return 0; |
| 556 | |
| 557 | out_err: |
| 558 | |
| 559 | list_for_each_entry_safe(entry, next_entry, &free_entries, list) { |
| 560 | list_del(&entry->list); |
| 561 | kfree(entry); |
| 562 | } |
| 563 | |
| 564 | return -ENOMEM; |
| 565 | } |
| 566 | |
| 567 | static ssize_t filter_read(struct file *file, char __user *user_buf, |
| 568 | size_t count, loff_t *ppos) |
| 569 | { |
| 570 | char buf[NAME_MAX_LEN + 1]; |
| 571 | unsigned long flags; |
| 572 | int len; |
| 573 | |
| 574 | if (!current_driver_name[0]) |
| 575 | return 0; |
| 576 | |
| 577 | /* |
| 578 | * We can't copy to userspace directly because current_driver_name can |
| 579 | * only be read under the driver_name_lock with irqs disabled. So |
| 580 | * create a temporary copy first. |
| 581 | */ |
| 582 | read_lock_irqsave(&driver_name_lock, flags); |
| 583 | len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name); |
| 584 | read_unlock_irqrestore(&driver_name_lock, flags); |
| 585 | |
| 586 | return simple_read_from_buffer(user_buf, count, ppos, buf, len); |
| 587 | } |
| 588 | |
| 589 | static ssize_t filter_write(struct file *file, const char __user *userbuf, |
| 590 | size_t count, loff_t *ppos) |
| 591 | { |
| 592 | char buf[NAME_MAX_LEN]; |
| 593 | unsigned long flags; |
| 594 | size_t len; |
| 595 | int i; |
| 596 | |
| 597 | /* |
| 598 | * We can't copy from userspace directly. Access to |
| 599 | * current_driver_name is protected with a write_lock with irqs |
| 600 | * disabled. Since copy_from_user can fault and may sleep we |
| 601 | * need to copy to temporary buffer first |
| 602 | */ |
| 603 | len = min(count, (size_t)(NAME_MAX_LEN - 1)); |
| 604 | if (copy_from_user(buf, userbuf, len)) |
| 605 | return -EFAULT; |
| 606 | |
| 607 | buf[len] = 0; |
| 608 | |
| 609 | write_lock_irqsave(&driver_name_lock, flags); |
| 610 | |
| 611 | /* |
| 612 | * Now handle the string we got from userspace very carefully. |
| 613 | * The rules are: |
| 614 | * - only use the first token we got |
| 615 | * - token delimiter is everything looking like a space |
| 616 | * character (' ', '\n', '\t' ...) |
| 617 | * |
| 618 | */ |
| 619 | if (!isalnum(buf[0])) { |
| 620 | /* |
| 621 | * If the first character userspace gave us is not |
| 622 | * alphanumerical then assume the filter should be |
| 623 | * switched off. |
| 624 | */ |
| 625 | if (current_driver_name[0]) |
| 626 | pr_info("DMA-API: switching off dma-debug driver filter\n"); |
| 627 | current_driver_name[0] = 0; |
| 628 | current_driver = NULL; |
| 629 | goto out_unlock; |
| 630 | } |
| 631 | |
| 632 | /* |
| 633 | * Now parse out the first token and use it as the name for the |
| 634 | * driver to filter for. |
| 635 | */ |
| 636 | for (i = 0; i < NAME_MAX_LEN - 1; ++i) { |
| 637 | current_driver_name[i] = buf[i]; |
| 638 | if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0) |
| 639 | break; |
| 640 | } |
| 641 | current_driver_name[i] = 0; |
| 642 | current_driver = NULL; |
| 643 | |
| 644 | pr_info("DMA-API: enable driver filter for driver [%s]\n", |
| 645 | current_driver_name); |
| 646 | |
| 647 | out_unlock: |
| 648 | write_unlock_irqrestore(&driver_name_lock, flags); |
| 649 | |
| 650 | return count; |
| 651 | } |
| 652 | |
| 653 | static const struct file_operations filter_fops = { |
| 654 | .read = filter_read, |
| 655 | .write = filter_write, |
| 656 | .llseek = default_llseek, |
| 657 | }; |
| 658 | |
| 659 | static int dma_debug_fs_init(void) |
| 660 | { |
| 661 | dma_debug_dent = debugfs_create_dir("dma-api", NULL); |
| 662 | if (!dma_debug_dent) { |
| 663 | pr_err("DMA-API: can not create debugfs directory\n"); |
| 664 | return -ENOMEM; |
| 665 | } |
| 666 | |
| 667 | global_disable_dent = debugfs_create_bool("disabled", 0444, |
| 668 | dma_debug_dent, |
| 669 | &global_disable); |
| 670 | if (!global_disable_dent) |
| 671 | goto out_err; |
| 672 | |
| 673 | error_count_dent = debugfs_create_u32("error_count", 0444, |
| 674 | dma_debug_dent, &error_count); |
| 675 | if (!error_count_dent) |
| 676 | goto out_err; |
| 677 | |
| 678 | show_all_errors_dent = debugfs_create_u32("all_errors", 0644, |
| 679 | dma_debug_dent, |
| 680 | &show_all_errors); |
| 681 | if (!show_all_errors_dent) |
| 682 | goto out_err; |
| 683 | |
| 684 | show_num_errors_dent = debugfs_create_u32("num_errors", 0644, |
| 685 | dma_debug_dent, |
| 686 | &show_num_errors); |
| 687 | if (!show_num_errors_dent) |
| 688 | goto out_err; |
| 689 | |
| 690 | num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444, |
| 691 | dma_debug_dent, |
| 692 | &num_free_entries); |
| 693 | if (!num_free_entries_dent) |
| 694 | goto out_err; |
| 695 | |
| 696 | min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444, |
| 697 | dma_debug_dent, |
| 698 | &min_free_entries); |
| 699 | if (!min_free_entries_dent) |
| 700 | goto out_err; |
| 701 | |
| 702 | filter_dent = debugfs_create_file("driver_filter", 0644, |
| 703 | dma_debug_dent, NULL, &filter_fops); |
| 704 | if (!filter_dent) |
| 705 | goto out_err; |
| 706 | |
| 707 | return 0; |
| 708 | |
| 709 | out_err: |
| 710 | debugfs_remove_recursive(dma_debug_dent); |
| 711 | |
| 712 | return -ENOMEM; |
| 713 | } |
| 714 | |
| 715 | static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry) |
| 716 | { |
| 717 | struct dma_debug_entry *entry; |
| 718 | unsigned long flags; |
| 719 | int count = 0, i; |
| 720 | |
| 721 | local_irq_save(flags); |
| 722 | |
| 723 | for (i = 0; i < HASH_SIZE; ++i) { |
| 724 | spin_lock(&dma_entry_hash[i].lock); |
| 725 | list_for_each_entry(entry, &dma_entry_hash[i].list, list) { |
| 726 | if (entry->dev == dev) { |
| 727 | count += 1; |
| 728 | *out_entry = entry; |
| 729 | } |
| 730 | } |
| 731 | spin_unlock(&dma_entry_hash[i].lock); |
| 732 | } |
| 733 | |
| 734 | local_irq_restore(flags); |
| 735 | |
| 736 | return count; |
| 737 | } |
| 738 | |
| 739 | static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data) |
| 740 | { |
| 741 | struct device *dev = data; |
| 742 | struct dma_debug_entry *uninitialized_var(entry); |
| 743 | int count; |
| 744 | |
| 745 | if (global_disable) |
| 746 | return 0; |
| 747 | |
| 748 | switch (action) { |
| 749 | case BUS_NOTIFY_UNBOUND_DRIVER: |
| 750 | count = device_dma_allocations(dev, &entry); |
| 751 | if (count == 0) |
| 752 | break; |
| 753 | err_printk(dev, entry, "DMA-API: device driver has pending " |
| 754 | "DMA allocations while released from device " |
| 755 | "[count=%d]\n" |
| 756 | "One of leaked entries details: " |
| 757 | "[device address=0x%016llx] [size=%llu bytes] " |
| 758 | "[mapped with %s] [mapped as %s]\n", |
| 759 | count, entry->dev_addr, entry->size, |
| 760 | dir2name[entry->direction], type2name[entry->type]); |
| 761 | break; |
| 762 | default: |
| 763 | break; |
| 764 | } |
| 765 | |
| 766 | return 0; |
| 767 | } |
| 768 | |
| 769 | void dma_debug_add_bus(struct bus_type *bus) |
| 770 | { |
| 771 | struct notifier_block *nb; |
| 772 | |
| 773 | if (global_disable) |
| 774 | return; |
| 775 | |
| 776 | nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); |
| 777 | if (nb == NULL) { |
| 778 | pr_err("dma_debug_add_bus: out of memory\n"); |
| 779 | return; |
| 780 | } |
| 781 | |
| 782 | nb->notifier_call = dma_debug_device_change; |
| 783 | |
| 784 | bus_register_notifier(bus, nb); |
| 785 | } |
| 786 | |
| 787 | /* |
| 788 | * Let the architectures decide how many entries should be preallocated. |
| 789 | */ |
| 790 | void dma_debug_init(u32 num_entries) |
| 791 | { |
| 792 | int i; |
| 793 | |
| 794 | if (global_disable) |
| 795 | return; |
| 796 | |
| 797 | for (i = 0; i < HASH_SIZE; ++i) { |
| 798 | INIT_LIST_HEAD(&dma_entry_hash[i].list); |
| 799 | spin_lock_init(&dma_entry_hash[i].lock); |
| 800 | } |
| 801 | |
| 802 | if (dma_debug_fs_init() != 0) { |
| 803 | pr_err("DMA-API: error creating debugfs entries - disabling\n"); |
| 804 | global_disable = true; |
| 805 | |
| 806 | return; |
| 807 | } |
| 808 | |
| 809 | if (req_entries) |
| 810 | num_entries = req_entries; |
| 811 | |
| 812 | if (prealloc_memory(num_entries) != 0) { |
| 813 | pr_err("DMA-API: debugging out of memory error - disabled\n"); |
| 814 | global_disable = true; |
| 815 | |
| 816 | return; |
| 817 | } |
| 818 | |
| 819 | nr_total_entries = num_free_entries; |
| 820 | |
| 821 | pr_info("DMA-API: debugging enabled by kernel config\n"); |
| 822 | } |
| 823 | |
| 824 | static __init int dma_debug_cmdline(char *str) |
| 825 | { |
| 826 | if (!str) |
| 827 | return -EINVAL; |
| 828 | |
| 829 | if (strncmp(str, "off", 3) == 0) { |
| 830 | pr_info("DMA-API: debugging disabled on kernel command line\n"); |
| 831 | global_disable = true; |
| 832 | } |
| 833 | |
| 834 | return 0; |
| 835 | } |
| 836 | |
| 837 | static __init int dma_debug_entries_cmdline(char *str) |
| 838 | { |
| 839 | int res; |
| 840 | |
| 841 | if (!str) |
| 842 | return -EINVAL; |
| 843 | |
| 844 | res = get_option(&str, &req_entries); |
| 845 | |
| 846 | if (!res) |
| 847 | req_entries = 0; |
| 848 | |
| 849 | return 0; |
| 850 | } |
| 851 | |
| 852 | __setup("dma_debug=", dma_debug_cmdline); |
| 853 | __setup("dma_debug_entries=", dma_debug_entries_cmdline); |
| 854 | |
| 855 | static void check_unmap(struct dma_debug_entry *ref) |
| 856 | { |
| 857 | struct dma_debug_entry *entry; |
| 858 | struct hash_bucket *bucket; |
| 859 | unsigned long flags; |
| 860 | |
| 861 | bucket = get_hash_bucket(ref, &flags); |
| 862 | entry = bucket_find_exact(bucket, ref); |
| 863 | |
| 864 | if (!entry) { |
| 865 | if (dma_mapping_error(ref->dev, ref->dev_addr)) { |
| 866 | err_printk(ref->dev, NULL, |
| 867 | "DMA-API: device driver tries " |
| 868 | "to free an invalid DMA memory address\n"); |
| 869 | return; |
| 870 | } |
| 871 | err_printk(ref->dev, NULL, "DMA-API: device driver tries " |
| 872 | "to free DMA memory it has not allocated " |
| 873 | "[device address=0x%016llx] [size=%llu bytes]\n", |
| 874 | ref->dev_addr, ref->size); |
| 875 | goto out; |
| 876 | } |
| 877 | |
| 878 | if (ref->size != entry->size) { |
| 879 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
| 880 | "DMA memory with different size " |
| 881 | "[device address=0x%016llx] [map size=%llu bytes] " |
| 882 | "[unmap size=%llu bytes]\n", |
| 883 | ref->dev_addr, entry->size, ref->size); |
| 884 | } |
| 885 | |
| 886 | if (ref->type != entry->type) { |
| 887 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
| 888 | "DMA memory with wrong function " |
| 889 | "[device address=0x%016llx] [size=%llu bytes] " |
| 890 | "[mapped as %s] [unmapped as %s]\n", |
| 891 | ref->dev_addr, ref->size, |
| 892 | type2name[entry->type], type2name[ref->type]); |
| 893 | } else if ((entry->type == dma_debug_coherent) && |
| 894 | (ref->paddr != entry->paddr)) { |
| 895 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
| 896 | "DMA memory with different CPU address " |
| 897 | "[device address=0x%016llx] [size=%llu bytes] " |
| 898 | "[cpu alloc address=0x%016llx] " |
| 899 | "[cpu free address=0x%016llx]", |
| 900 | ref->dev_addr, ref->size, |
| 901 | (unsigned long long)entry->paddr, |
| 902 | (unsigned long long)ref->paddr); |
| 903 | } |
| 904 | |
| 905 | if (ref->sg_call_ents && ref->type == dma_debug_sg && |
| 906 | ref->sg_call_ents != entry->sg_call_ents) { |
| 907 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
| 908 | "DMA sg list with different entry count " |
| 909 | "[map count=%d] [unmap count=%d]\n", |
| 910 | entry->sg_call_ents, ref->sg_call_ents); |
| 911 | } |
| 912 | |
| 913 | /* |
| 914 | * This may be no bug in reality - but most implementations of the |
| 915 | * DMA API don't handle this properly, so check for it here |
| 916 | */ |
| 917 | if (ref->direction != entry->direction) { |
| 918 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
| 919 | "DMA memory with different direction " |
| 920 | "[device address=0x%016llx] [size=%llu bytes] " |
| 921 | "[mapped with %s] [unmapped with %s]\n", |
| 922 | ref->dev_addr, ref->size, |
| 923 | dir2name[entry->direction], |
| 924 | dir2name[ref->direction]); |
| 925 | } |
| 926 | |
| 927 | if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { |
| 928 | err_printk(ref->dev, entry, |
| 929 | "DMA-API: device driver failed to check map error" |
| 930 | "[device address=0x%016llx] [size=%llu bytes] " |
| 931 | "[mapped as %s]", |
| 932 | ref->dev_addr, ref->size, |
| 933 | type2name[entry->type]); |
| 934 | } |
| 935 | |
| 936 | hash_bucket_del(entry); |
| 937 | dma_entry_free(entry); |
| 938 | |
| 939 | out: |
| 940 | put_hash_bucket(bucket, &flags); |
| 941 | } |
| 942 | |
| 943 | static void check_for_stack(struct device *dev, void *addr) |
| 944 | { |
| 945 | if (object_is_on_stack(addr)) |
| 946 | err_printk(dev, NULL, "DMA-API: device driver maps memory from" |
| 947 | "stack [addr=%p]\n", addr); |
| 948 | } |
| 949 | |
| 950 | static inline bool overlap(void *addr, unsigned long len, void *start, void *end) |
| 951 | { |
| 952 | unsigned long a1 = (unsigned long)addr; |
| 953 | unsigned long b1 = a1 + len; |
| 954 | unsigned long a2 = (unsigned long)start; |
| 955 | unsigned long b2 = (unsigned long)end; |
| 956 | |
| 957 | return !(b1 <= a2 || a1 >= b2); |
| 958 | } |
| 959 | |
| 960 | static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) |
| 961 | { |
| 962 | if (overlap(addr, len, _text, _etext) || |
| 963 | overlap(addr, len, __start_rodata, __end_rodata)) |
| 964 | err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len); |
| 965 | } |
| 966 | |
| 967 | static void check_sync(struct device *dev, |
| 968 | struct dma_debug_entry *ref, |
| 969 | bool to_cpu) |
| 970 | { |
| 971 | struct dma_debug_entry *entry; |
| 972 | struct hash_bucket *bucket; |
| 973 | unsigned long flags; |
| 974 | |
| 975 | bucket = get_hash_bucket(ref, &flags); |
| 976 | |
| 977 | entry = bucket_find_contain(&bucket, ref, &flags); |
| 978 | |
| 979 | if (!entry) { |
| 980 | err_printk(dev, NULL, "DMA-API: device driver tries " |
| 981 | "to sync DMA memory it has not allocated " |
| 982 | "[device address=0x%016llx] [size=%llu bytes]\n", |
| 983 | (unsigned long long)ref->dev_addr, ref->size); |
| 984 | goto out; |
| 985 | } |
| 986 | |
| 987 | if (ref->size > entry->size) { |
| 988 | err_printk(dev, entry, "DMA-API: device driver syncs" |
| 989 | " DMA memory outside allocated range " |
| 990 | "[device address=0x%016llx] " |
| 991 | "[allocation size=%llu bytes] " |
| 992 | "[sync offset+size=%llu]\n", |
| 993 | entry->dev_addr, entry->size, |
| 994 | ref->size); |
| 995 | } |
| 996 | |
| 997 | if (entry->direction == DMA_BIDIRECTIONAL) |
| 998 | goto out; |
| 999 | |
| 1000 | if (ref->direction != entry->direction) { |
| 1001 | err_printk(dev, entry, "DMA-API: device driver syncs " |
| 1002 | "DMA memory with different direction " |
| 1003 | "[device address=0x%016llx] [size=%llu bytes] " |
| 1004 | "[mapped with %s] [synced with %s]\n", |
| 1005 | (unsigned long long)ref->dev_addr, entry->size, |
| 1006 | dir2name[entry->direction], |
| 1007 | dir2name[ref->direction]); |
| 1008 | } |
| 1009 | |
| 1010 | if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) && |
| 1011 | !(ref->direction == DMA_TO_DEVICE)) |
| 1012 | err_printk(dev, entry, "DMA-API: device driver syncs " |
| 1013 | "device read-only DMA memory for cpu " |
| 1014 | "[device address=0x%016llx] [size=%llu bytes] " |
| 1015 | "[mapped with %s] [synced with %s]\n", |
| 1016 | (unsigned long long)ref->dev_addr, entry->size, |
| 1017 | dir2name[entry->direction], |
| 1018 | dir2name[ref->direction]); |
| 1019 | |
| 1020 | if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) && |
| 1021 | !(ref->direction == DMA_FROM_DEVICE)) |
| 1022 | err_printk(dev, entry, "DMA-API: device driver syncs " |
| 1023 | "device write-only DMA memory to device " |
| 1024 | "[device address=0x%016llx] [size=%llu bytes] " |
| 1025 | "[mapped with %s] [synced with %s]\n", |
| 1026 | (unsigned long long)ref->dev_addr, entry->size, |
| 1027 | dir2name[entry->direction], |
| 1028 | dir2name[ref->direction]); |
| 1029 | |
| 1030 | out: |
| 1031 | put_hash_bucket(bucket, &flags); |
| 1032 | } |
| 1033 | |
| 1034 | void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, |
| 1035 | size_t size, int direction, dma_addr_t dma_addr, |
| 1036 | bool map_single) |
| 1037 | { |
| 1038 | struct dma_debug_entry *entry; |
| 1039 | |
| 1040 | if (unlikely(global_disable)) |
| 1041 | return; |
| 1042 | |
| 1043 | if (dma_mapping_error(dev, dma_addr)) |
| 1044 | return; |
| 1045 | |
| 1046 | entry = dma_entry_alloc(); |
| 1047 | if (!entry) |
| 1048 | return; |
| 1049 | |
| 1050 | entry->dev = dev; |
| 1051 | entry->type = dma_debug_page; |
| 1052 | entry->paddr = page_to_phys(page) + offset; |
| 1053 | entry->dev_addr = dma_addr; |
| 1054 | entry->size = size; |
| 1055 | entry->direction = direction; |
| 1056 | entry->map_err_type = MAP_ERR_NOT_CHECKED; |
| 1057 | |
| 1058 | if (map_single) |
| 1059 | entry->type = dma_debug_single; |
| 1060 | |
| 1061 | if (!PageHighMem(page)) { |
| 1062 | void *addr = page_address(page) + offset; |
| 1063 | |
| 1064 | check_for_stack(dev, addr); |
| 1065 | check_for_illegal_area(dev, addr, size); |
| 1066 | } |
| 1067 | |
| 1068 | add_dma_entry(entry); |
| 1069 | } |
| 1070 | EXPORT_SYMBOL(debug_dma_map_page); |
| 1071 | |
| 1072 | void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) |
| 1073 | { |
| 1074 | struct dma_debug_entry ref; |
| 1075 | struct dma_debug_entry *entry; |
| 1076 | struct hash_bucket *bucket; |
| 1077 | unsigned long flags; |
| 1078 | |
| 1079 | if (unlikely(global_disable)) |
| 1080 | return; |
| 1081 | |
| 1082 | ref.dev = dev; |
| 1083 | ref.dev_addr = dma_addr; |
| 1084 | bucket = get_hash_bucket(&ref, &flags); |
| 1085 | entry = bucket_find_exact(bucket, &ref); |
| 1086 | |
| 1087 | if (!entry) |
| 1088 | goto out; |
| 1089 | |
| 1090 | entry->map_err_type = MAP_ERR_CHECKED; |
| 1091 | out: |
| 1092 | put_hash_bucket(bucket, &flags); |
| 1093 | } |
| 1094 | EXPORT_SYMBOL(debug_dma_mapping_error); |
| 1095 | |
| 1096 | void debug_dma_unmap_page(struct device *dev, dma_addr_t addr, |
| 1097 | size_t size, int direction, bool map_single) |
| 1098 | { |
| 1099 | struct dma_debug_entry ref = { |
| 1100 | .type = dma_debug_page, |
| 1101 | .dev = dev, |
| 1102 | .dev_addr = addr, |
| 1103 | .size = size, |
| 1104 | .direction = direction, |
| 1105 | }; |
| 1106 | |
| 1107 | if (unlikely(global_disable)) |
| 1108 | return; |
| 1109 | |
| 1110 | if (map_single) |
| 1111 | ref.type = dma_debug_single; |
| 1112 | |
| 1113 | check_unmap(&ref); |
| 1114 | } |
| 1115 | EXPORT_SYMBOL(debug_dma_unmap_page); |
| 1116 | |
| 1117 | void debug_dma_map_sg(struct device *dev, struct scatterlist *sg, |
| 1118 | int nents, int mapped_ents, int direction) |
| 1119 | { |
| 1120 | struct dma_debug_entry *entry; |
| 1121 | struct scatterlist *s; |
| 1122 | int i; |
| 1123 | |
| 1124 | if (unlikely(global_disable)) |
| 1125 | return; |
| 1126 | |
| 1127 | for_each_sg(sg, s, mapped_ents, i) { |
| 1128 | entry = dma_entry_alloc(); |
| 1129 | if (!entry) |
| 1130 | return; |
| 1131 | |
| 1132 | entry->type = dma_debug_sg; |
| 1133 | entry->dev = dev; |
| 1134 | entry->paddr = sg_phys(s); |
| 1135 | entry->size = sg_dma_len(s); |
| 1136 | entry->dev_addr = sg_dma_address(s); |
| 1137 | entry->direction = direction; |
| 1138 | entry->sg_call_ents = nents; |
| 1139 | entry->sg_mapped_ents = mapped_ents; |
| 1140 | |
| 1141 | if (!PageHighMem(sg_page(s))) { |
| 1142 | check_for_stack(dev, sg_virt(s)); |
| 1143 | check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s)); |
| 1144 | } |
| 1145 | |
| 1146 | add_dma_entry(entry); |
| 1147 | } |
| 1148 | } |
| 1149 | EXPORT_SYMBOL(debug_dma_map_sg); |
| 1150 | |
| 1151 | static int get_nr_mapped_entries(struct device *dev, |
| 1152 | struct dma_debug_entry *ref) |
| 1153 | { |
| 1154 | struct dma_debug_entry *entry; |
| 1155 | struct hash_bucket *bucket; |
| 1156 | unsigned long flags; |
| 1157 | int mapped_ents; |
| 1158 | |
| 1159 | bucket = get_hash_bucket(ref, &flags); |
| 1160 | entry = bucket_find_exact(bucket, ref); |
| 1161 | mapped_ents = 0; |
| 1162 | |
| 1163 | if (entry) |
| 1164 | mapped_ents = entry->sg_mapped_ents; |
| 1165 | put_hash_bucket(bucket, &flags); |
| 1166 | |
| 1167 | return mapped_ents; |
| 1168 | } |
| 1169 | |
| 1170 | void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, |
| 1171 | int nelems, int dir) |
| 1172 | { |
| 1173 | struct scatterlist *s; |
| 1174 | int mapped_ents = 0, i; |
| 1175 | |
| 1176 | if (unlikely(global_disable)) |
| 1177 | return; |
| 1178 | |
| 1179 | for_each_sg(sglist, s, nelems, i) { |
| 1180 | |
| 1181 | struct dma_debug_entry ref = { |
| 1182 | .type = dma_debug_sg, |
| 1183 | .dev = dev, |
| 1184 | .paddr = sg_phys(s), |
| 1185 | .dev_addr = sg_dma_address(s), |
| 1186 | .size = sg_dma_len(s), |
| 1187 | .direction = dir, |
| 1188 | .sg_call_ents = nelems, |
| 1189 | }; |
| 1190 | |
| 1191 | if (mapped_ents && i >= mapped_ents) |
| 1192 | break; |
| 1193 | |
| 1194 | if (!i) |
| 1195 | mapped_ents = get_nr_mapped_entries(dev, &ref); |
| 1196 | |
| 1197 | check_unmap(&ref); |
| 1198 | } |
| 1199 | } |
| 1200 | EXPORT_SYMBOL(debug_dma_unmap_sg); |
| 1201 | |
| 1202 | void debug_dma_alloc_coherent(struct device *dev, size_t size, |
| 1203 | dma_addr_t dma_addr, void *virt) |
| 1204 | { |
| 1205 | struct dma_debug_entry *entry; |
| 1206 | |
| 1207 | if (unlikely(global_disable)) |
| 1208 | return; |
| 1209 | |
| 1210 | if (unlikely(virt == NULL)) |
| 1211 | return; |
| 1212 | |
| 1213 | entry = dma_entry_alloc(); |
| 1214 | if (!entry) |
| 1215 | return; |
| 1216 | |
| 1217 | entry->type = dma_debug_coherent; |
| 1218 | entry->dev = dev; |
| 1219 | entry->paddr = virt_to_phys(virt); |
| 1220 | entry->size = size; |
| 1221 | entry->dev_addr = dma_addr; |
| 1222 | entry->direction = DMA_BIDIRECTIONAL; |
| 1223 | |
| 1224 | add_dma_entry(entry); |
| 1225 | } |
| 1226 | EXPORT_SYMBOL(debug_dma_alloc_coherent); |
| 1227 | |
| 1228 | void debug_dma_free_coherent(struct device *dev, size_t size, |
| 1229 | void *virt, dma_addr_t addr) |
| 1230 | { |
| 1231 | struct dma_debug_entry ref = { |
| 1232 | .type = dma_debug_coherent, |
| 1233 | .dev = dev, |
| 1234 | .paddr = virt_to_phys(virt), |
| 1235 | .dev_addr = addr, |
| 1236 | .size = size, |
| 1237 | .direction = DMA_BIDIRECTIONAL, |
| 1238 | }; |
| 1239 | |
| 1240 | if (unlikely(global_disable)) |
| 1241 | return; |
| 1242 | |
| 1243 | check_unmap(&ref); |
| 1244 | } |
| 1245 | EXPORT_SYMBOL(debug_dma_free_coherent); |
| 1246 | |
| 1247 | void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, |
| 1248 | size_t size, int direction) |
| 1249 | { |
| 1250 | struct dma_debug_entry ref; |
| 1251 | |
| 1252 | if (unlikely(global_disable)) |
| 1253 | return; |
| 1254 | |
| 1255 | ref.type = dma_debug_single; |
| 1256 | ref.dev = dev; |
| 1257 | ref.dev_addr = dma_handle; |
| 1258 | ref.size = size; |
| 1259 | ref.direction = direction; |
| 1260 | ref.sg_call_ents = 0; |
| 1261 | |
| 1262 | check_sync(dev, &ref, true); |
| 1263 | } |
| 1264 | EXPORT_SYMBOL(debug_dma_sync_single_for_cpu); |
| 1265 | |
| 1266 | void debug_dma_sync_single_for_device(struct device *dev, |
| 1267 | dma_addr_t dma_handle, size_t size, |
| 1268 | int direction) |
| 1269 | { |
| 1270 | struct dma_debug_entry ref; |
| 1271 | |
| 1272 | if (unlikely(global_disable)) |
| 1273 | return; |
| 1274 | |
| 1275 | ref.type = dma_debug_single; |
| 1276 | ref.dev = dev; |
| 1277 | ref.dev_addr = dma_handle; |
| 1278 | ref.size = size; |
| 1279 | ref.direction = direction; |
| 1280 | ref.sg_call_ents = 0; |
| 1281 | |
| 1282 | check_sync(dev, &ref, false); |
| 1283 | } |
| 1284 | EXPORT_SYMBOL(debug_dma_sync_single_for_device); |
| 1285 | |
| 1286 | void debug_dma_sync_single_range_for_cpu(struct device *dev, |
| 1287 | dma_addr_t dma_handle, |
| 1288 | unsigned long offset, size_t size, |
| 1289 | int direction) |
| 1290 | { |
| 1291 | struct dma_debug_entry ref; |
| 1292 | |
| 1293 | if (unlikely(global_disable)) |
| 1294 | return; |
| 1295 | |
| 1296 | ref.type = dma_debug_single; |
| 1297 | ref.dev = dev; |
| 1298 | ref.dev_addr = dma_handle; |
| 1299 | ref.size = offset + size; |
| 1300 | ref.direction = direction; |
| 1301 | ref.sg_call_ents = 0; |
| 1302 | |
| 1303 | check_sync(dev, &ref, true); |
| 1304 | } |
| 1305 | EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu); |
| 1306 | |
| 1307 | void debug_dma_sync_single_range_for_device(struct device *dev, |
| 1308 | dma_addr_t dma_handle, |
| 1309 | unsigned long offset, |
| 1310 | size_t size, int direction) |
| 1311 | { |
| 1312 | struct dma_debug_entry ref; |
| 1313 | |
| 1314 | if (unlikely(global_disable)) |
| 1315 | return; |
| 1316 | |
| 1317 | ref.type = dma_debug_single; |
| 1318 | ref.dev = dev; |
| 1319 | ref.dev_addr = dma_handle; |
| 1320 | ref.size = offset + size; |
| 1321 | ref.direction = direction; |
| 1322 | ref.sg_call_ents = 0; |
| 1323 | |
| 1324 | check_sync(dev, &ref, false); |
| 1325 | } |
| 1326 | EXPORT_SYMBOL(debug_dma_sync_single_range_for_device); |
| 1327 | |
| 1328 | void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, |
| 1329 | int nelems, int direction) |
| 1330 | { |
| 1331 | struct scatterlist *s; |
| 1332 | int mapped_ents = 0, i; |
| 1333 | |
| 1334 | if (unlikely(global_disable)) |
| 1335 | return; |
| 1336 | |
| 1337 | for_each_sg(sg, s, nelems, i) { |
| 1338 | |
| 1339 | struct dma_debug_entry ref = { |
| 1340 | .type = dma_debug_sg, |
| 1341 | .dev = dev, |
| 1342 | .paddr = sg_phys(s), |
| 1343 | .dev_addr = sg_dma_address(s), |
| 1344 | .size = sg_dma_len(s), |
| 1345 | .direction = direction, |
| 1346 | .sg_call_ents = nelems, |
| 1347 | }; |
| 1348 | |
| 1349 | if (!i) |
| 1350 | mapped_ents = get_nr_mapped_entries(dev, &ref); |
| 1351 | |
| 1352 | if (i >= mapped_ents) |
| 1353 | break; |
| 1354 | |
| 1355 | check_sync(dev, &ref, true); |
| 1356 | } |
| 1357 | } |
| 1358 | EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu); |
| 1359 | |
| 1360 | void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, |
| 1361 | int nelems, int direction) |
| 1362 | { |
| 1363 | struct scatterlist *s; |
| 1364 | int mapped_ents = 0, i; |
| 1365 | |
| 1366 | if (unlikely(global_disable)) |
| 1367 | return; |
| 1368 | |
| 1369 | for_each_sg(sg, s, nelems, i) { |
| 1370 | |
| 1371 | struct dma_debug_entry ref = { |
| 1372 | .type = dma_debug_sg, |
| 1373 | .dev = dev, |
| 1374 | .paddr = sg_phys(s), |
| 1375 | .dev_addr = sg_dma_address(s), |
| 1376 | .size = sg_dma_len(s), |
| 1377 | .direction = direction, |
| 1378 | .sg_call_ents = nelems, |
| 1379 | }; |
| 1380 | if (!i) |
| 1381 | mapped_ents = get_nr_mapped_entries(dev, &ref); |
| 1382 | |
| 1383 | if (i >= mapped_ents) |
| 1384 | break; |
| 1385 | |
| 1386 | check_sync(dev, &ref, false); |
| 1387 | } |
| 1388 | } |
| 1389 | EXPORT_SYMBOL(debug_dma_sync_sg_for_device); |
| 1390 | |
| 1391 | static int __init dma_debug_driver_setup(char *str) |
| 1392 | { |
| 1393 | int i; |
| 1394 | |
| 1395 | for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) { |
| 1396 | current_driver_name[i] = *str; |
| 1397 | if (*str == 0) |
| 1398 | break; |
| 1399 | } |
| 1400 | |
| 1401 | if (current_driver_name[0]) |
| 1402 | pr_info("DMA-API: enable driver filter for driver [%s]\n", |
| 1403 | current_driver_name); |
| 1404 | |
| 1405 | |
| 1406 | return 1; |
| 1407 | } |
| 1408 | __setup("dma_debug_driver=", dma_debug_driver_setup); |