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   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/dma-debug.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/debugfs.h>
  25 #include <linux/device.h>
  26 #include <linux/types.h>
  27 #include <linux/sched.h>
  28 #include <linux/list.h>
  29 #include <linux/slab.h>
  30
  31 #define HASH_SIZE       1024ULL
  32 #define HASH_FN_SHIFT   13
  33 #define HASH_FN_MASK    (HASH_SIZE - 1)
  34
  35 enum {
  36         dma_debug_single,
  37         dma_debug_page,
  38         dma_debug_sg,
  39         dma_debug_coherent,
  40 };
  41
  42 struct dma_debug_entry {
  43         struct list_head list;
  44         struct device    *dev;
  45         int              type;
  46         phys_addr_t      paddr;
  47         u64              dev_addr;
  48         u64              size;
  49         int              direction;
  50         int              sg_call_ents;
  51         int              sg_mapped_ents;
  52 };
  53
  54 struct hash_bucket {
  55         struct list_head list;
  56         spinlock_t lock;
  57 } ____cacheline_aligned_in_smp;
  58
  59 /* Hash list to save the allocated dma addresses */
  60 static struct hash_bucket dma_entry_hash[HASH_SIZE];
  61 /* List of pre-allocated dma_debug_entry's */
  62 static LIST_HEAD(free_entries);
  63 /* Lock for the list above */
  64 static DEFINE_SPINLOCK(free_entries_lock);
  65
  66 /* Global disable flag - will be set in case of an error */
  67 static bool global_disable __read_mostly;
  68
  69 /* Global error count */
  70 static u32 error_count;
  71
  72 /* Global error show enable*/
  73 static u32 show_all_errors __read_mostly;
  74 /* Number of errors to show */
  75 static u32 show_num_errors = 1;
  76
  77 static u32 num_free_entries;
  78 static u32 min_free_entries;
  79
  80 /* number of preallocated entries requested by kernel cmdline */
  81 static u32 req_entries;
  82
  83 /* debugfs dentry's for the stuff above */
  84 static struct dentry *dma_debug_dent        __read_mostly;
  85 static struct dentry *global_disable_dent   __read_mostly;
  86 static struct dentry *error_count_dent      __read_mostly;
  87 static struct dentry *show_all_errors_dent  __read_mostly;
  88 static struct dentry *show_num_errors_dent  __read_mostly;
  89 static struct dentry *num_free_entries_dent __read_mostly;
  90 static struct dentry *min_free_entries_dent __read_mostly;
  91
  92 static const char *type2name[4] = { "single", "page",
  93                                     "scather-gather", "coherent" };
  94
  95 static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
  96                                    "DMA_FROM_DEVICE", "DMA_NONE" };
  97
  98 /*
  99  * The access to some variables in this macro is racy. We can't use atomic_t
 100  * here because all these variables are exported to debugfs. Some of them even
 101  * writeable. This is also the reason why a lock won't help much. But anyway,
 102  * the races are no big deal. Here is why:
 103  *
 104  *   error_count: the addition is racy, but the worst thing that can happen is
 105  *                that we don't count some errors
 106  *   show_num_errors: the subtraction is racy. Also no big deal because in
 107  *                    worst case this will result in one warning more in the
 108  *                    system log than the user configured. This variable is
 109  *                    writeable via debugfs.
 110  */
 111 #define err_printk(dev, format, arg...) do {                    \
 112                 error_count += 1;                               \
 113                 if (show_all_errors || show_num_errors > 0) {   \
 114                         WARN(1, "%s %s: " format,               \
 115                              dev_driver_string(dev),            \
 116                              dev_name(dev) , ## arg);           \
 117                 }                                               \
 118                 if (!show_all_errors && show_num_errors > 0)    \
 119                         show_num_errors -= 1;                   \
 120         } while (0);
 121
 122 /*
 123  * Hash related functions
 124  *
 125  * Every DMA-API request is saved into a struct dma_debug_entry. To
 126  * have quick access to these structs they are stored into a hash.
 127  */
 128 static int hash_fn(struct dma_debug_entry *entry)
 129 {
 130         /*
 131          * Hash function is based on the dma address.
 132          * We use bits 20-27 here as the index into the hash
 133          */
 134         return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
 135 }
 136
 137 /*
 138  * Request exclusive access to a hash bucket for a given dma_debug_entry.
 139  */
 140 static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
 141                                            unsigned long *flags)
 142 {
 143         int idx = hash_fn(entry);
 144         unsigned long __flags;
 145
 146         spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
 147         *flags = __flags;
 148         return &dma_entry_hash[idx];
 149 }
 150
 151 /*
 152  * Give up exclusive access to the hash bucket
 153  */
 154 static void put_hash_bucket(struct hash_bucket *bucket,
 155                             unsigned long *flags)
 156 {
 157         unsigned long __flags = *flags;
 158
 159         spin_unlock_irqrestore(&bucket->lock, __flags);
 160 }
 161
 162 /*
 163  * Search a given entry in the hash bucket list
 164  */
 165 static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket,
 166                                                 struct dma_debug_entry *ref)
 167 {
 168         struct dma_debug_entry *entry;
 169
 170         list_for_each_entry(entry, &bucket->list, list) {
 171                 if ((entry->dev_addr == ref->dev_addr) &&
 172                     (entry->dev == ref->dev))
 173                         return entry;
 174         }
 175
 176         return NULL;
 177 }
 178
 179 /*
 180  * Add an entry to a hash bucket
 181  */
 182 static void hash_bucket_add(struct hash_bucket *bucket,
 183                             struct dma_debug_entry *entry)
 184 {
 185         list_add_tail(&entry->list, &bucket->list);
 186 }
 187
 188 /*
 189  * Remove entry from a hash bucket list
 190  */
 191 static void hash_bucket_del(struct dma_debug_entry *entry)
 192 {
 193         list_del(&entry->list);
 194 }
 195
 196 /*
 197  * Wrapper function for adding an entry to the hash.
 198  * This function takes care of locking itself.
 199  */
 200 static void add_dma_entry(struct dma_debug_entry *entry)
 201 {
 202         struct hash_bucket *bucket;
 203         unsigned long flags;
 204
 205         bucket = get_hash_bucket(entry, &flags);
 206         hash_bucket_add(bucket, entry);
 207         put_hash_bucket(bucket, &flags);
 208 }
 209
 210 /* struct dma_entry allocator
 211  *
 212  * The next two functions implement the allocator for
 213  * struct dma_debug_entries.
 214  */
 215 static struct dma_debug_entry *dma_entry_alloc(void)
 216 {
 217         struct dma_debug_entry *entry = NULL;
 218         unsigned long flags;
 219
 220         spin_lock_irqsave(&free_entries_lock, flags);
 221
 222         if (list_empty(&free_entries)) {
 223                 printk(KERN_ERR "DMA-API: debugging out of memory "
 224                                 "- disabling\n");
 225                 global_disable = true;
 226                 goto out;
 227         }
 228
 229         entry = list_entry(free_entries.next, struct dma_debug_entry, list);
 230         list_del(&entry->list);
 231         memset(entry, 0, sizeof(*entry));
 232
 233         num_free_entries -= 1;
 234         if (num_free_entries < min_free_entries)
 235                 min_free_entries = num_free_entries;
 236
 237 out:
 238         spin_unlock_irqrestore(&free_entries_lock, flags);
 239
 240         return entry;
 241 }
 242
 243 static void dma_entry_free(struct dma_debug_entry *entry)
 244 {
 245         unsigned long flags;
 246
 247         /*
 248          * add to beginning of the list - this way the entries are
 249          * more likely cache hot when they are reallocated.
 250          */
 251         spin_lock_irqsave(&free_entries_lock, flags);
 252         list_add(&entry->list, &free_entries);
 253         num_free_entries += 1;
 254         spin_unlock_irqrestore(&free_entries_lock, flags);
 255 }
 256
 257 /*
 258  * DMA-API debugging init code
 259  *
 260  * The init code does two things:
 261  *   1. Initialize core data structures
 262  *   2. Preallocate a given number of dma_debug_entry structs
 263  */
 264
 265 static int prealloc_memory(u32 num_entries)
 266 {
 267         struct dma_debug_entry *entry, *next_entry;
 268         int i;
 269
 270         for (i = 0; i < num_entries; ++i) {
 271                 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 272                 if (!entry)
 273                         goto out_err;
 274
 275                 list_add_tail(&entry->list, &free_entries);
 276         }
 277
 278         num_free_entries = num_entries;
 279         min_free_entries = num_entries;
 280
 281         printk(KERN_INFO "DMA-API: preallocated %d debug entries\n",
 282                         num_entries);
 283
 284         return 0;
 285
 286 out_err:
 287
 288         list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
 289                 list_del(&entry->list);
 290                 kfree(entry);
 291         }
 292
 293         return -ENOMEM;
 294 }
 295
 296 static int dma_debug_fs_init(void)
 297 {
 298         dma_debug_dent = debugfs_create_dir("dma-api", NULL);
 299         if (!dma_debug_dent) {
 300                 printk(KERN_ERR "DMA-API: can not create debugfs directory\n");
 301                 return -ENOMEM;
 302         }
 303
 304         global_disable_dent = debugfs_create_bool("disabled", 0444,
 305                         dma_debug_dent,
 306                         (u32 *)&global_disable);
 307         if (!global_disable_dent)
 308                 goto out_err;
 309
 310         error_count_dent = debugfs_create_u32("error_count", 0444,
 311                         dma_debug_dent, &error_count);
 312         if (!error_count_dent)
 313                 goto out_err;
 314
 315         show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
 316                         dma_debug_dent,
 317                         &show_all_errors);
 318         if (!show_all_errors_dent)
 319                 goto out_err;
 320
 321         show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
 322                         dma_debug_dent,
 323                         &show_num_errors);
 324         if (!show_num_errors_dent)
 325                 goto out_err;
 326
 327         num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
 328                         dma_debug_dent,
 329                         &num_free_entries);
 330         if (!num_free_entries_dent)
 331                 goto out_err;
 332
 333         min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
 334                         dma_debug_dent,
 335                         &min_free_entries);
 336         if (!min_free_entries_dent)
 337                 goto out_err;
 338
 339         return 0;
 340
 341 out_err:
 342         debugfs_remove_recursive(dma_debug_dent);
 343
 344         return -ENOMEM;
 345 }
 346
 347
 348 /*
 349  * Let the architectures decide how many entries should be preallocated.
 350  */
 351 void dma_debug_init(u32 num_entries)
 352 {
 353         int i;
 354
 355         if (global_disable)
 356                 return;
 357
 358         for (i = 0; i < HASH_SIZE; ++i) {
 359                 INIT_LIST_HEAD(&dma_entry_hash[i].list);
 360                 dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
 361         }
 362
 363         if (dma_debug_fs_init() != 0) {
 364                 printk(KERN_ERR "DMA-API: error creating debugfs entries "
 365                                 "- disabling\n");
 366                 global_disable = true;
 367
 368                 return;
 369         }
 370
 371         if (req_entries)
 372                 num_entries = req_entries;
 373
 374         if (prealloc_memory(num_entries) != 0) {
 375                 printk(KERN_ERR "DMA-API: debugging out of memory error "
 376                                 "- disabled\n");
 377                 global_disable = true;
 378
 379                 return;
 380         }
 381
 382         printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
 383 }
 384
 385 static __init int dma_debug_cmdline(char *str)
 386 {
 387         if (!str)
 388                 return -EINVAL;
 389
 390         if (strncmp(str, "off", 3) == 0) {
 391                 printk(KERN_INFO "DMA-API: debugging disabled on kernel "
 392                                  "command line\n");
 393                 global_disable = true;
 394         }
 395
 396         return 0;
 397 }
 398
 399 static __init int dma_debug_entries_cmdline(char *str)
 400 {
 401         int res;
 402
 403         if (!str)
 404                 return -EINVAL;
 405
 406         res = get_option(&str, &req_entries);
 407
 408         if (!res)
 409                 req_entries = 0;
 410
 411         return 0;
 412 }
 413
 414 __setup("dma_debug=", dma_debug_cmdline);
 415 __setup("dma_debug_entries=", dma_debug_entries_cmdline);
 416
 417 static void check_unmap(struct dma_debug_entry *ref)
 418 {
 419         struct dma_debug_entry *entry;
 420         struct hash_bucket *bucket;
 421         unsigned long flags;
 422
 423         if (dma_mapping_error(ref->dev, ref->dev_addr))
 424                 return;
 425
 426         bucket = get_hash_bucket(ref, &flags);
 427         entry = hash_bucket_find(bucket, ref);
 428
 429         if (!entry) {
 430                 err_printk(ref->dev, "DMA-API: device driver tries "
 431                            "to free DMA memory it has not allocated "
 432                            "[device address=0x%016llx] [size=%llu bytes]\n",
 433                            ref->dev_addr, ref->size);
 434                 goto out;
 435         }
 436
 437         if (ref->size != entry->size) {
 438                 err_printk(ref->dev, "DMA-API: device driver frees "
 439                            "DMA memory with different size "
 440                            "[device address=0x%016llx] [map size=%llu bytes] "
 441                            "[unmap size=%llu bytes]\n",
 442                            ref->dev_addr, entry->size, ref->size);
 443         }
 444
 445         if (ref->type != entry->type) {
 446                 err_printk(ref->dev, "DMA-API: device driver frees "
 447                            "DMA memory with wrong function "
 448                            "[device address=0x%016llx] [size=%llu bytes] "
 449                            "[mapped as %s] [unmapped as %s]\n",
 450                            ref->dev_addr, ref->size,
 451                            type2name[entry->type], type2name[ref->type]);
 452         } else if ((entry->type == dma_debug_coherent) &&
 453                    (ref->paddr != entry->paddr)) {
 454                 err_printk(ref->dev, "DMA-API: device driver frees "
 455                            "DMA memory with different CPU address "
 456                            "[device address=0x%016llx] [size=%llu bytes] "
 457                            "[cpu alloc address=%p] [cpu free address=%p]",
 458                            ref->dev_addr, ref->size,
 459                            (void *)entry->paddr, (void *)ref->paddr);
 460         }
 461
 462         if (ref->sg_call_ents && ref->type == dma_debug_sg &&
 463             ref->sg_call_ents != entry->sg_call_ents) {
 464                 err_printk(ref->dev, "DMA-API: device driver frees "
 465                            "DMA sg list with different entry count "
 466                            "[map count=%d] [unmap count=%d]\n",
 467                            entry->sg_call_ents, ref->sg_call_ents);
 468         }
 469
 470         /*
 471          * This may be no bug in reality - but most implementations of the
 472          * DMA API don't handle this properly, so check for it here
 473          */
 474         if (ref->direction != entry->direction) {
 475                 err_printk(ref->dev, "DMA-API: device driver frees "
 476                            "DMA memory with different direction "
 477                            "[device address=0x%016llx] [size=%llu bytes] "
 478                            "[mapped with %s] [unmapped with %s]\n",
 479                            ref->dev_addr, ref->size,
 480                            dir2name[entry->direction],
 481                            dir2name[ref->direction]);
 482         }
 483
 484         hash_bucket_del(entry);
 485         dma_entry_free(entry);
 486
 487 out:
 488         put_hash_bucket(bucket, &flags);
 489 }
 490
 491 static void check_for_stack(struct device *dev, void *addr)
 492 {
 493         if (object_is_on_stack(addr))
 494                 err_printk(dev, "DMA-API: device driver maps memory from stack"
 495                                 " [addr=%p]\n", addr);
 496 }
 497
 498 static void check_sync(struct device *dev, dma_addr_t addr,
 499                        u64 size, u64 offset, int direction, bool to_cpu)
 500 {
 501         struct dma_debug_entry ref = {
 502                 .dev            = dev,
 503                 .dev_addr       = addr,
 504                 .size           = size,
 505                 .direction      = direction,
 506         };
 507         struct dma_debug_entry *entry;
 508         struct hash_bucket *bucket;
 509         unsigned long flags;
 510
 511         bucket = get_hash_bucket(&ref, &flags);
 512
 513         entry = hash_bucket_find(bucket, &ref);
 514
 515         if (!entry) {
 516                 err_printk(dev, "DMA-API: device driver tries "
 517                                 "to sync DMA memory it has not allocated "
 518                                 "[device address=0x%016llx] [size=%llu bytes]\n",
 519                                 addr, size);
 520                 goto out;
 521         }
 522
 523         if ((offset + size) > entry->size) {
 524                 err_printk(dev, "DMA-API: device driver syncs"
 525                                 " DMA memory outside allocated range "
 526                                 "[device address=0x%016llx] "
 527                                 "[allocation size=%llu bytes] [sync offset=%llu] "
 528                                 "[sync size=%llu]\n", entry->dev_addr, entry->size,
 529                                 offset, size);
 530         }
 531
 532         if (direction != entry->direction) {
 533                 err_printk(dev, "DMA-API: device driver syncs "
 534                                 "DMA memory with different direction "
 535                                 "[device address=0x%016llx] [size=%llu bytes] "
 536                                 "[mapped with %s] [synced with %s]\n",
 537                                 addr, entry->size,
 538                                 dir2name[entry->direction],
 539                                 dir2name[direction]);
 540         }
 541
 542         if (entry->direction == DMA_BIDIRECTIONAL)
 543                 goto out;
 544
 545         if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
 546                       !(direction == DMA_TO_DEVICE))
 547                 err_printk(dev, "DMA-API: device driver syncs "
 548                                 "device read-only DMA memory for cpu "
 549                                 "[device address=0x%016llx] [size=%llu bytes] "
 550                                 "[mapped with %s] [synced with %s]\n",
 551                                 addr, entry->size,
 552                                 dir2name[entry->direction],
 553                                 dir2name[direction]);
 554
 555         if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
 556                        !(direction == DMA_FROM_DEVICE))
 557                 err_printk(dev, "DMA-API: device driver syncs "
 558                                 "device write-only DMA memory to device "
 559                                 "[device address=0x%016llx] [size=%llu bytes] "
 560                                 "[mapped with %s] [synced with %s]\n",
 561                                 addr, entry->size,
 562                                 dir2name[entry->direction],
 563                                 dir2name[direction]);
 564
 565 out:
 566         put_hash_bucket(bucket, &flags);
 567
 568 }
 569
 570 void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
 571                         size_t size, int direction, dma_addr_t dma_addr,
 572                         bool map_single)
 573 {
 574         struct dma_debug_entry *entry;
 575
 576         if (unlikely(global_disable))
 577                 return;
 578
 579         if (unlikely(dma_mapping_error(dev, dma_addr)))
 580                 return;
 581
 582         entry = dma_entry_alloc();
 583         if (!entry)
 584                 return;
 585
 586         entry->dev       = dev;
 587         entry->type      = dma_debug_page;
 588         entry->paddr     = page_to_phys(page) + offset;
 589         entry->dev_addr  = dma_addr;
 590         entry->size      = size;
 591         entry->direction = direction;
 592
 593         if (map_single) {
 594                 entry->type = dma_debug_single;
 595                 check_for_stack(dev, page_address(page) + offset);
 596         }
 597
 598         add_dma_entry(entry);
 599 }
 600 EXPORT_SYMBOL(debug_dma_map_page);
 601
 602 void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
 603                           size_t size, int direction, bool map_single)
 604 {
 605         struct dma_debug_entry ref = {
 606                 .type           = dma_debug_page,
 607                 .dev            = dev,
 608                 .dev_addr       = addr,
 609                 .size           = size,
 610                 .direction      = direction,
 611         };
 612
 613         if (unlikely(global_disable))
 614                 return;
 615
 616         if (map_single)
 617                 ref.type = dma_debug_single;
 618
 619         check_unmap(&ref);
 620 }
 621 EXPORT_SYMBOL(debug_dma_unmap_page);
 622
 623 void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
 624                       int nents, int mapped_ents, int direction)
 625 {
 626         struct dma_debug_entry *entry;
 627         struct scatterlist *s;
 628         int i;
 629
 630         if (unlikely(global_disable))
 631                 return;
 632
 633         for_each_sg(sg, s, mapped_ents, i) {
 634                 entry = dma_entry_alloc();
 635                 if (!entry)
 636                         return;
 637
 638                 entry->type           = dma_debug_sg;
 639                 entry->dev            = dev;
 640                 entry->paddr          = sg_phys(s);
 641                 entry->size           = s->length;
 642                 entry->dev_addr       = s->dma_address;
 643                 entry->direction      = direction;
 644                 entry->sg_call_ents   = nents;
 645                 entry->sg_mapped_ents = mapped_ents;
 646
 647                 check_for_stack(dev, sg_virt(s));
 648
 649                 add_dma_entry(entry);
 650         }
 651 }
 652 EXPORT_SYMBOL(debug_dma_map_sg);
 653
 654 void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
 655                         int nelems, int dir)
 656 {
 657         struct dma_debug_entry *entry;
 658         struct scatterlist *s;
 659         int mapped_ents = 0, i;
 660         unsigned long flags;
 661
 662         if (unlikely(global_disable))
 663                 return;
 664
 665         for_each_sg(sglist, s, nelems, i) {
 666
 667                 struct dma_debug_entry ref = {
 668                         .type           = dma_debug_sg,
 669                         .dev            = dev,
 670                         .paddr          = sg_phys(s),
 671                         .dev_addr       = s->dma_address,
 672                         .size           = s->length,
 673                         .direction      = dir,
 674                         .sg_call_ents   = 0,
 675                 };
 676
 677                 if (mapped_ents && i >= mapped_ents)
 678                         break;
 679
 680                 if (mapped_ents == 0) {
 681                         struct hash_bucket *bucket;
 682                         ref.sg_call_ents = nelems;
 683                         bucket = get_hash_bucket(&ref, &flags);
 684                         entry = hash_bucket_find(bucket, &ref);
 685                         if (entry)
 686                                 mapped_ents = entry->sg_mapped_ents;
 687                         put_hash_bucket(bucket, &flags);
 688                 }
 689
 690                 check_unmap(&ref);
 691         }
 692 }
 693 EXPORT_SYMBOL(debug_dma_unmap_sg);
 694
 695 void debug_dma_alloc_coherent(struct device *dev, size_t size,
 696                               dma_addr_t dma_addr, void *virt)
 697 {
 698         struct dma_debug_entry *entry;
 699
 700         if (unlikely(global_disable))
 701                 return;
 702
 703         if (unlikely(virt == NULL))
 704                 return;
 705
 706         entry = dma_entry_alloc();
 707         if (!entry)
 708                 return;
 709
 710         entry->type      = dma_debug_coherent;
 711         entry->dev       = dev;
 712         entry->paddr     = virt_to_phys(virt);
 713         entry->size      = size;
 714         entry->dev_addr  = dma_addr;
 715         entry->direction = DMA_BIDIRECTIONAL;
 716
 717         add_dma_entry(entry);
 718 }
 719 EXPORT_SYMBOL(debug_dma_alloc_coherent);
 720
 721 void debug_dma_free_coherent(struct device *dev, size_t size,
 722                          void *virt, dma_addr_t addr)
 723 {
 724         struct dma_debug_entry ref = {
 725                 .type           = dma_debug_coherent,
 726                 .dev            = dev,
 727                 .paddr          = virt_to_phys(virt),
 728                 .dev_addr       = addr,
 729                 .size           = size,
 730                 .direction      = DMA_BIDIRECTIONAL,
 731         };
 732
 733         if (unlikely(global_disable))
 734                 return;
 735
 736         check_unmap(&ref);
 737 }
 738 EXPORT_SYMBOL(debug_dma_free_coherent);
 739
 740 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
 741                                    size_t size, int direction)
 742 {
 743         if (unlikely(global_disable))
 744                 return;
 745
 746         check_sync(dev, dma_handle, size, 0, direction, true);
 747 }
 748 EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
 749
 750 void debug_dma_sync_single_for_device(struct device *dev,
 751                                       dma_addr_t dma_handle, size_t size,
 752                                       int direction)
 753 {
 754         if (unlikely(global_disable))
 755                 return;
 756
 757         check_sync(dev, dma_handle, size, 0, direction, false);
 758 }
 759 EXPORT_SYMBOL(debug_dma_sync_single_for_device);
 760
 761 void debug_dma_sync_single_range_for_cpu(struct device *dev,
 762                                          dma_addr_t dma_handle,
 763                                          unsigned long offset, size_t size,
 764                                          int direction)
 765 {
 766         if (unlikely(global_disable))
 767                 return;
 768
 769         check_sync(dev, dma_handle, size, offset, direction, true);
 770 }
 771 EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
 772
 773 void debug_dma_sync_single_range_for_device(struct device *dev,
 774                                             dma_addr_t dma_handle,
 775                                             unsigned long offset,
 776                                             size_t size, int direction)
 777 {
 778         if (unlikely(global_disable))
 779                 return;
 780
 781         check_sync(dev, dma_handle, size, offset, direction, false);
 782 }
 783 EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
 784
 785 void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 786                                int nelems, int direction)
 787 {
 788         struct scatterlist *s;
 789         int i;
 790
 791         if (unlikely(global_disable))
 792                 return;
 793
 794         for_each_sg(sg, s, nelems, i) {
 795                 check_sync(dev, s->dma_address, s->dma_length, 0,
 796                                 direction, true);
 797         }
 798 }
 799 EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
 800
 801 void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 802                                   int nelems, int direction)
 803 {
 804         struct scatterlist *s;
 805         int i;
 806
 807         if (unlikely(global_disable))
 808                 return;
 809
 810         for_each_sg(sg, s, nelems, i) {
 811                 check_sync(dev, s->dma_address, s->dma_length, 0,
 812                                 direction, false);
 813         }
 814 }
 815 EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
 816