Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
[linux-2.6] / lib / dma-debug.c
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/device.h>
27 #include <linux/types.h>
28 #include <linux/sched.h>
29 #include <linux/list.h>
30 #include <linux/slab.h>
31
32 #include <asm/sections.h>
33
34 #define HASH_SIZE       1024ULL
35 #define HASH_FN_SHIFT   13
36 #define HASH_FN_MASK    (HASH_SIZE - 1)
37
38 enum {
39         dma_debug_single,
40         dma_debug_page,
41         dma_debug_sg,
42         dma_debug_coherent,
43 };
44
45 #define DMA_DEBUG_STACKTRACE_ENTRIES 5
46
47 struct dma_debug_entry {
48         struct list_head list;
49         struct device    *dev;
50         int              type;
51         phys_addr_t      paddr;
52         u64              dev_addr;
53         u64              size;
54         int              direction;
55         int              sg_call_ents;
56         int              sg_mapped_ents;
57 #ifdef CONFIG_STACKTRACE
58         struct           stack_trace stacktrace;
59         unsigned long    st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
60 #endif
61 };
62
63 struct hash_bucket {
64         struct list_head list;
65         spinlock_t lock;
66 } ____cacheline_aligned_in_smp;
67
68 /* Hash list to save the allocated dma addresses */
69 static struct hash_bucket dma_entry_hash[HASH_SIZE];
70 /* List of pre-allocated dma_debug_entry's */
71 static LIST_HEAD(free_entries);
72 /* Lock for the list above */
73 static DEFINE_SPINLOCK(free_entries_lock);
74
75 /* Global disable flag - will be set in case of an error */
76 static bool global_disable __read_mostly;
77
78 /* Global error count */
79 static u32 error_count;
80
81 /* Global error show enable*/
82 static u32 show_all_errors __read_mostly;
83 /* Number of errors to show */
84 static u32 show_num_errors = 1;
85
86 static u32 num_free_entries;
87 static u32 min_free_entries;
88
89 /* number of preallocated entries requested by kernel cmdline */
90 static u32 req_entries;
91
92 /* debugfs dentry's for the stuff above */
93 static struct dentry *dma_debug_dent        __read_mostly;
94 static struct dentry *global_disable_dent   __read_mostly;
95 static struct dentry *error_count_dent      __read_mostly;
96 static struct dentry *show_all_errors_dent  __read_mostly;
97 static struct dentry *show_num_errors_dent  __read_mostly;
98 static struct dentry *num_free_entries_dent __read_mostly;
99 static struct dentry *min_free_entries_dent __read_mostly;
100
101 static const char *type2name[4] = { "single", "page",
102                                     "scather-gather", "coherent" };
103
104 static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
105                                    "DMA_FROM_DEVICE", "DMA_NONE" };
106
107 /*
108  * The access to some variables in this macro is racy. We can't use atomic_t
109  * here because all these variables are exported to debugfs. Some of them even
110  * writeable. This is also the reason why a lock won't help much. But anyway,
111  * the races are no big deal. Here is why:
112  *
113  *   error_count: the addition is racy, but the worst thing that can happen is
114  *                that we don't count some errors
115  *   show_num_errors: the subtraction is racy. Also no big deal because in
116  *                    worst case this will result in one warning more in the
117  *                    system log than the user configured. This variable is
118  *                    writeable via debugfs.
119  */
120 static inline void dump_entry_trace(struct dma_debug_entry *entry)
121 {
122 #ifdef CONFIG_STACKTRACE
123         if (entry) {
124                 printk(KERN_WARNING "Mapped at:\n");
125                 print_stack_trace(&entry->stacktrace, 0);
126         }
127 #endif
128 }
129
130 #define err_printk(dev, entry, format, arg...) do {             \
131                 error_count += 1;                               \
132                 if (show_all_errors || show_num_errors > 0) {   \
133                         WARN(1, "%s %s: " format,               \
134                              dev_driver_string(dev),            \
135                              dev_name(dev) , ## arg);           \
136                         dump_entry_trace(entry);                \
137                 }                                               \
138                 if (!show_all_errors && show_num_errors > 0)    \
139                         show_num_errors -= 1;                   \
140         } while (0);
141
142 /*
143  * Hash related functions
144  *
145  * Every DMA-API request is saved into a struct dma_debug_entry. To
146  * have quick access to these structs they are stored into a hash.
147  */
148 static int hash_fn(struct dma_debug_entry *entry)
149 {
150         /*
151          * Hash function is based on the dma address.
152          * We use bits 20-27 here as the index into the hash
153          */
154         return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
155 }
156
157 /*
158  * Request exclusive access to a hash bucket for a given dma_debug_entry.
159  */
160 static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
161                                            unsigned long *flags)
162 {
163         int idx = hash_fn(entry);
164         unsigned long __flags;
165
166         spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
167         *flags = __flags;
168         return &dma_entry_hash[idx];
169 }
170
171 /*
172  * Give up exclusive access to the hash bucket
173  */
174 static void put_hash_bucket(struct hash_bucket *bucket,
175                             unsigned long *flags)
176 {
177         unsigned long __flags = *flags;
178
179         spin_unlock_irqrestore(&bucket->lock, __flags);
180 }
181
182 /*
183  * Search a given entry in the hash bucket list
184  */
185 static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket,
186                                                 struct dma_debug_entry *ref)
187 {
188         struct dma_debug_entry *entry;
189
190         list_for_each_entry(entry, &bucket->list, list) {
191                 if ((entry->dev_addr == ref->dev_addr) &&
192                     (entry->dev == ref->dev))
193                         return entry;
194         }
195
196         return NULL;
197 }
198
199 /*
200  * Add an entry to a hash bucket
201  */
202 static void hash_bucket_add(struct hash_bucket *bucket,
203                             struct dma_debug_entry *entry)
204 {
205         list_add_tail(&entry->list, &bucket->list);
206 }
207
208 /*
209  * Remove entry from a hash bucket list
210  */
211 static void hash_bucket_del(struct dma_debug_entry *entry)
212 {
213         list_del(&entry->list);
214 }
215
216 /*
217  * Dump mapping entries for debugging purposes
218  */
219 void debug_dma_dump_mappings(struct device *dev)
220 {
221         int idx;
222
223         for (idx = 0; idx < HASH_SIZE; idx++) {
224                 struct hash_bucket *bucket = &dma_entry_hash[idx];
225                 struct dma_debug_entry *entry;
226                 unsigned long flags;
227
228                 spin_lock_irqsave(&bucket->lock, flags);
229
230                 list_for_each_entry(entry, &bucket->list, list) {
231                         if (!dev || dev == entry->dev) {
232                                 dev_info(entry->dev,
233                                          "%s idx %d P=%Lx D=%Lx L=%Lx %s\n",
234                                          type2name[entry->type], idx,
235                                          (unsigned long long)entry->paddr,
236                                          entry->dev_addr, entry->size,
237                                          dir2name[entry->direction]);
238                         }
239                 }
240
241                 spin_unlock_irqrestore(&bucket->lock, flags);
242         }
243 }
244 EXPORT_SYMBOL(debug_dma_dump_mappings);
245
246 /*
247  * Wrapper function for adding an entry to the hash.
248  * This function takes care of locking itself.
249  */
250 static void add_dma_entry(struct dma_debug_entry *entry)
251 {
252         struct hash_bucket *bucket;
253         unsigned long flags;
254
255         bucket = get_hash_bucket(entry, &flags);
256         hash_bucket_add(bucket, entry);
257         put_hash_bucket(bucket, &flags);
258 }
259
260 /* struct dma_entry allocator
261  *
262  * The next two functions implement the allocator for
263  * struct dma_debug_entries.
264  */
265 static struct dma_debug_entry *dma_entry_alloc(void)
266 {
267         struct dma_debug_entry *entry = NULL;
268         unsigned long flags;
269
270         spin_lock_irqsave(&free_entries_lock, flags);
271
272         if (list_empty(&free_entries)) {
273                 printk(KERN_ERR "DMA-API: debugging out of memory "
274                                 "- disabling\n");
275                 global_disable = true;
276                 goto out;
277         }
278
279         entry = list_entry(free_entries.next, struct dma_debug_entry, list);
280         list_del(&entry->list);
281         memset(entry, 0, sizeof(*entry));
282
283 #ifdef CONFIG_STACKTRACE
284         entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
285         entry->stacktrace.entries = entry->st_entries;
286         entry->stacktrace.skip = 2;
287         save_stack_trace(&entry->stacktrace);
288 #endif
289         num_free_entries -= 1;
290         if (num_free_entries < min_free_entries)
291                 min_free_entries = num_free_entries;
292
293 out:
294         spin_unlock_irqrestore(&free_entries_lock, flags);
295
296         return entry;
297 }
298
299 static void dma_entry_free(struct dma_debug_entry *entry)
300 {
301         unsigned long flags;
302
303         /*
304          * add to beginning of the list - this way the entries are
305          * more likely cache hot when they are reallocated.
306          */
307         spin_lock_irqsave(&free_entries_lock, flags);
308         list_add(&entry->list, &free_entries);
309         num_free_entries += 1;
310         spin_unlock_irqrestore(&free_entries_lock, flags);
311 }
312
313 /*
314  * DMA-API debugging init code
315  *
316  * The init code does two things:
317  *   1. Initialize core data structures
318  *   2. Preallocate a given number of dma_debug_entry structs
319  */
320
321 static int prealloc_memory(u32 num_entries)
322 {
323         struct dma_debug_entry *entry, *next_entry;
324         int i;
325
326         for (i = 0; i < num_entries; ++i) {
327                 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
328                 if (!entry)
329                         goto out_err;
330
331                 list_add_tail(&entry->list, &free_entries);
332         }
333
334         num_free_entries = num_entries;
335         min_free_entries = num_entries;
336
337         printk(KERN_INFO "DMA-API: preallocated %d debug entries\n",
338                         num_entries);
339
340         return 0;
341
342 out_err:
343
344         list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
345                 list_del(&entry->list);
346                 kfree(entry);
347         }
348
349         return -ENOMEM;
350 }
351
352 static int dma_debug_fs_init(void)
353 {
354         dma_debug_dent = debugfs_create_dir("dma-api", NULL);
355         if (!dma_debug_dent) {
356                 printk(KERN_ERR "DMA-API: can not create debugfs directory\n");
357                 return -ENOMEM;
358         }
359
360         global_disable_dent = debugfs_create_bool("disabled", 0444,
361                         dma_debug_dent,
362                         (u32 *)&global_disable);
363         if (!global_disable_dent)
364                 goto out_err;
365
366         error_count_dent = debugfs_create_u32("error_count", 0444,
367                         dma_debug_dent, &error_count);
368         if (!error_count_dent)
369                 goto out_err;
370
371         show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
372                         dma_debug_dent,
373                         &show_all_errors);
374         if (!show_all_errors_dent)
375                 goto out_err;
376
377         show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
378                         dma_debug_dent,
379                         &show_num_errors);
380         if (!show_num_errors_dent)
381                 goto out_err;
382
383         num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
384                         dma_debug_dent,
385                         &num_free_entries);
386         if (!num_free_entries_dent)
387                 goto out_err;
388
389         min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
390                         dma_debug_dent,
391                         &min_free_entries);
392         if (!min_free_entries_dent)
393                 goto out_err;
394
395         return 0;
396
397 out_err:
398         debugfs_remove_recursive(dma_debug_dent);
399
400         return -ENOMEM;
401 }
402
403 void dma_debug_add_bus(struct bus_type *bus)
404 {
405         /* FIXME: register notifier */
406 }
407
408 /*
409  * Let the architectures decide how many entries should be preallocated.
410  */
411 void dma_debug_init(u32 num_entries)
412 {
413         int i;
414
415         if (global_disable)
416                 return;
417
418         for (i = 0; i < HASH_SIZE; ++i) {
419                 INIT_LIST_HEAD(&dma_entry_hash[i].list);
420                 dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
421         }
422
423         if (dma_debug_fs_init() != 0) {
424                 printk(KERN_ERR "DMA-API: error creating debugfs entries "
425                                 "- disabling\n");
426                 global_disable = true;
427
428                 return;
429         }
430
431         if (req_entries)
432                 num_entries = req_entries;
433
434         if (prealloc_memory(num_entries) != 0) {
435                 printk(KERN_ERR "DMA-API: debugging out of memory error "
436                                 "- disabled\n");
437                 global_disable = true;
438
439                 return;
440         }
441
442         printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
443 }
444
445 static __init int dma_debug_cmdline(char *str)
446 {
447         if (!str)
448                 return -EINVAL;
449
450         if (strncmp(str, "off", 3) == 0) {
451                 printk(KERN_INFO "DMA-API: debugging disabled on kernel "
452                                  "command line\n");
453                 global_disable = true;
454         }
455
456         return 0;
457 }
458
459 static __init int dma_debug_entries_cmdline(char *str)
460 {
461         int res;
462
463         if (!str)
464                 return -EINVAL;
465
466         res = get_option(&str, &req_entries);
467
468         if (!res)
469                 req_entries = 0;
470
471         return 0;
472 }
473
474 __setup("dma_debug=", dma_debug_cmdline);
475 __setup("dma_debug_entries=", dma_debug_entries_cmdline);
476
477 static void check_unmap(struct dma_debug_entry *ref)
478 {
479         struct dma_debug_entry *entry;
480         struct hash_bucket *bucket;
481         unsigned long flags;
482
483         if (dma_mapping_error(ref->dev, ref->dev_addr)) {
484                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
485                            "to free an invalid DMA memory address\n");
486                 return;
487         }
488
489         bucket = get_hash_bucket(ref, &flags);
490         entry = hash_bucket_find(bucket, ref);
491
492         if (!entry) {
493                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
494                            "to free DMA memory it has not allocated "
495                            "[device address=0x%016llx] [size=%llu bytes]\n",
496                            ref->dev_addr, ref->size);
497                 goto out;
498         }
499
500         if (ref->size != entry->size) {
501                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
502                            "DMA memory with different size "
503                            "[device address=0x%016llx] [map size=%llu bytes] "
504                            "[unmap size=%llu bytes]\n",
505                            ref->dev_addr, entry->size, ref->size);
506         }
507
508         if (ref->type != entry->type) {
509                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
510                            "DMA memory with wrong function "
511                            "[device address=0x%016llx] [size=%llu bytes] "
512                            "[mapped as %s] [unmapped as %s]\n",
513                            ref->dev_addr, ref->size,
514                            type2name[entry->type], type2name[ref->type]);
515         } else if ((entry->type == dma_debug_coherent) &&
516                    (ref->paddr != entry->paddr)) {
517                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
518                            "DMA memory with different CPU address "
519                            "[device address=0x%016llx] [size=%llu bytes] "
520                            "[cpu alloc address=%p] [cpu free address=%p]",
521                            ref->dev_addr, ref->size,
522                            (void *)entry->paddr, (void *)ref->paddr);
523         }
524
525         if (ref->sg_call_ents && ref->type == dma_debug_sg &&
526             ref->sg_call_ents != entry->sg_call_ents) {
527                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
528                            "DMA sg list with different entry count "
529                            "[map count=%d] [unmap count=%d]\n",
530                            entry->sg_call_ents, ref->sg_call_ents);
531         }
532
533         /*
534          * This may be no bug in reality - but most implementations of the
535          * DMA API don't handle this properly, so check for it here
536          */
537         if (ref->direction != entry->direction) {
538                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
539                            "DMA memory with different direction "
540                            "[device address=0x%016llx] [size=%llu bytes] "
541                            "[mapped with %s] [unmapped with %s]\n",
542                            ref->dev_addr, ref->size,
543                            dir2name[entry->direction],
544                            dir2name[ref->direction]);
545         }
546
547         hash_bucket_del(entry);
548         dma_entry_free(entry);
549
550 out:
551         put_hash_bucket(bucket, &flags);
552 }
553
554 static void check_for_stack(struct device *dev, void *addr)
555 {
556         if (object_is_on_stack(addr))
557                 err_printk(dev, NULL, "DMA-API: device driver maps memory from"
558                                 "stack [addr=%p]\n", addr);
559 }
560
561 static inline bool overlap(void *addr, u64 size, void *start, void *end)
562 {
563         void *addr2 = (char *)addr + size;
564
565         return ((addr >= start && addr < end) ||
566                 (addr2 >= start && addr2 < end) ||
567                 ((addr < start) && (addr2 >= end)));
568 }
569
570 static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
571 {
572         if (overlap(addr, size, _text, _etext) ||
573             overlap(addr, size, __start_rodata, __end_rodata))
574                 err_printk(dev, NULL, "DMA-API: device driver maps "
575                                 "memory from kernel text or rodata "
576                                 "[addr=%p] [size=%llu]\n", addr, size);
577 }
578
579 static void check_sync(struct device *dev, dma_addr_t addr,
580                        u64 size, u64 offset, int direction, bool to_cpu)
581 {
582         struct dma_debug_entry ref = {
583                 .dev            = dev,
584                 .dev_addr       = addr,
585                 .size           = size,
586                 .direction      = direction,
587         };
588         struct dma_debug_entry *entry;
589         struct hash_bucket *bucket;
590         unsigned long flags;
591
592         bucket = get_hash_bucket(&ref, &flags);
593
594         entry = hash_bucket_find(bucket, &ref);
595
596         if (!entry) {
597                 err_printk(dev, NULL, "DMA-API: device driver tries "
598                                 "to sync DMA memory it has not allocated "
599                                 "[device address=0x%016llx] [size=%llu bytes]\n",
600                                 (unsigned long long)addr, size);
601                 goto out;
602         }
603
604         if ((offset + size) > entry->size) {
605                 err_printk(dev, entry, "DMA-API: device driver syncs"
606                                 " DMA memory outside allocated range "
607                                 "[device address=0x%016llx] "
608                                 "[allocation size=%llu bytes] [sync offset=%llu] "
609                                 "[sync size=%llu]\n", entry->dev_addr, entry->size,
610                                 offset, size);
611         }
612
613         if (direction != entry->direction) {
614                 err_printk(dev, entry, "DMA-API: device driver syncs "
615                                 "DMA memory with different direction "
616                                 "[device address=0x%016llx] [size=%llu bytes] "
617                                 "[mapped with %s] [synced with %s]\n",
618                                 (unsigned long long)addr, entry->size,
619                                 dir2name[entry->direction],
620                                 dir2name[direction]);
621         }
622
623         if (entry->direction == DMA_BIDIRECTIONAL)
624                 goto out;
625
626         if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
627                       !(direction == DMA_TO_DEVICE))
628                 err_printk(dev, entry, "DMA-API: device driver syncs "
629                                 "device read-only DMA memory for cpu "
630                                 "[device address=0x%016llx] [size=%llu bytes] "
631                                 "[mapped with %s] [synced with %s]\n",
632                                 (unsigned long long)addr, entry->size,
633                                 dir2name[entry->direction],
634                                 dir2name[direction]);
635
636         if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
637                        !(direction == DMA_FROM_DEVICE))
638                 err_printk(dev, entry, "DMA-API: device driver syncs "
639                                 "device write-only DMA memory to device "
640                                 "[device address=0x%016llx] [size=%llu bytes] "
641                                 "[mapped with %s] [synced with %s]\n",
642                                 (unsigned long long)addr, entry->size,
643                                 dir2name[entry->direction],
644                                 dir2name[direction]);
645
646 out:
647         put_hash_bucket(bucket, &flags);
648
649 }
650
651 void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
652                         size_t size, int direction, dma_addr_t dma_addr,
653                         bool map_single)
654 {
655         struct dma_debug_entry *entry;
656
657         if (unlikely(global_disable))
658                 return;
659
660         if (unlikely(dma_mapping_error(dev, dma_addr)))
661                 return;
662
663         entry = dma_entry_alloc();
664         if (!entry)
665                 return;
666
667         entry->dev       = dev;
668         entry->type      = dma_debug_page;
669         entry->paddr     = page_to_phys(page) + offset;
670         entry->dev_addr  = dma_addr;
671         entry->size      = size;
672         entry->direction = direction;
673
674         if (map_single)
675                 entry->type = dma_debug_single;
676
677         if (!PageHighMem(page)) {
678                 void *addr = ((char *)page_address(page)) + offset;
679                 check_for_stack(dev, addr);
680                 check_for_illegal_area(dev, addr, size);
681         }
682
683         add_dma_entry(entry);
684 }
685 EXPORT_SYMBOL(debug_dma_map_page);
686
687 void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
688                           size_t size, int direction, bool map_single)
689 {
690         struct dma_debug_entry ref = {
691                 .type           = dma_debug_page,
692                 .dev            = dev,
693                 .dev_addr       = addr,
694                 .size           = size,
695                 .direction      = direction,
696         };
697
698         if (unlikely(global_disable))
699                 return;
700
701         if (map_single)
702                 ref.type = dma_debug_single;
703
704         check_unmap(&ref);
705 }
706 EXPORT_SYMBOL(debug_dma_unmap_page);
707
708 void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
709                       int nents, int mapped_ents, int direction)
710 {
711         struct dma_debug_entry *entry;
712         struct scatterlist *s;
713         int i;
714
715         if (unlikely(global_disable))
716                 return;
717
718         for_each_sg(sg, s, mapped_ents, i) {
719                 entry = dma_entry_alloc();
720                 if (!entry)
721                         return;
722
723                 entry->type           = dma_debug_sg;
724                 entry->dev            = dev;
725                 entry->paddr          = sg_phys(s);
726                 entry->size           = s->length;
727                 entry->dev_addr       = s->dma_address;
728                 entry->direction      = direction;
729                 entry->sg_call_ents   = nents;
730                 entry->sg_mapped_ents = mapped_ents;
731
732                 if (!PageHighMem(sg_page(s))) {
733                         check_for_stack(dev, sg_virt(s));
734                         check_for_illegal_area(dev, sg_virt(s), s->length);
735                 }
736
737                 add_dma_entry(entry);
738         }
739 }
740 EXPORT_SYMBOL(debug_dma_map_sg);
741
742 void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
743                         int nelems, int dir)
744 {
745         struct dma_debug_entry *entry;
746         struct scatterlist *s;
747         int mapped_ents = 0, i;
748         unsigned long flags;
749
750         if (unlikely(global_disable))
751                 return;
752
753         for_each_sg(sglist, s, nelems, i) {
754
755                 struct dma_debug_entry ref = {
756                         .type           = dma_debug_sg,
757                         .dev            = dev,
758                         .paddr          = sg_phys(s),
759                         .dev_addr       = s->dma_address,
760                         .size           = s->length,
761                         .direction      = dir,
762                         .sg_call_ents   = 0,
763                 };
764
765                 if (mapped_ents && i >= mapped_ents)
766                         break;
767
768                 if (mapped_ents == 0) {
769                         struct hash_bucket *bucket;
770                         ref.sg_call_ents = nelems;
771                         bucket = get_hash_bucket(&ref, &flags);
772                         entry = hash_bucket_find(bucket, &ref);
773                         if (entry)
774                                 mapped_ents = entry->sg_mapped_ents;
775                         put_hash_bucket(bucket, &flags);
776                 }
777
778                 check_unmap(&ref);
779         }
780 }
781 EXPORT_SYMBOL(debug_dma_unmap_sg);
782
783 void debug_dma_alloc_coherent(struct device *dev, size_t size,
784                               dma_addr_t dma_addr, void *virt)
785 {
786         struct dma_debug_entry *entry;
787
788         if (unlikely(global_disable))
789                 return;
790
791         if (unlikely(virt == NULL))
792                 return;
793
794         entry = dma_entry_alloc();
795         if (!entry)
796                 return;
797
798         entry->type      = dma_debug_coherent;
799         entry->dev       = dev;
800         entry->paddr     = virt_to_phys(virt);
801         entry->size      = size;
802         entry->dev_addr  = dma_addr;
803         entry->direction = DMA_BIDIRECTIONAL;
804
805         add_dma_entry(entry);
806 }
807 EXPORT_SYMBOL(debug_dma_alloc_coherent);
808
809 void debug_dma_free_coherent(struct device *dev, size_t size,
810                          void *virt, dma_addr_t addr)
811 {
812         struct dma_debug_entry ref = {
813                 .type           = dma_debug_coherent,
814                 .dev            = dev,
815                 .paddr          = virt_to_phys(virt),
816                 .dev_addr       = addr,
817                 .size           = size,
818                 .direction      = DMA_BIDIRECTIONAL,
819         };
820
821         if (unlikely(global_disable))
822                 return;
823
824         check_unmap(&ref);
825 }
826 EXPORT_SYMBOL(debug_dma_free_coherent);
827
828 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
829                                    size_t size, int direction)
830 {
831         if (unlikely(global_disable))
832                 return;
833
834         check_sync(dev, dma_handle, size, 0, direction, true);
835 }
836 EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
837
838 void debug_dma_sync_single_for_device(struct device *dev,
839                                       dma_addr_t dma_handle, size_t size,
840                                       int direction)
841 {
842         if (unlikely(global_disable))
843                 return;
844
845         check_sync(dev, dma_handle, size, 0, direction, false);
846 }
847 EXPORT_SYMBOL(debug_dma_sync_single_for_device);
848
849 void debug_dma_sync_single_range_for_cpu(struct device *dev,
850                                          dma_addr_t dma_handle,
851                                          unsigned long offset, size_t size,
852                                          int direction)
853 {
854         if (unlikely(global_disable))
855                 return;
856
857         check_sync(dev, dma_handle, size, offset, direction, true);
858 }
859 EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
860
861 void debug_dma_sync_single_range_for_device(struct device *dev,
862                                             dma_addr_t dma_handle,
863                                             unsigned long offset,
864                                             size_t size, int direction)
865 {
866         if (unlikely(global_disable))
867                 return;
868
869         check_sync(dev, dma_handle, size, offset, direction, false);
870 }
871 EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
872
873 void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
874                                int nelems, int direction)
875 {
876         struct scatterlist *s;
877         int i;
878
879         if (unlikely(global_disable))
880                 return;
881
882         for_each_sg(sg, s, nelems, i) {
883                 check_sync(dev, s->dma_address, s->dma_length, 0,
884                                 direction, true);
885         }
886 }
887 EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
888
889 void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
890                                   int nelems, int direction)
891 {
892         struct scatterlist *s;
893         int i;
894
895         if (unlikely(global_disable))
896                 return;
897
898         for_each_sg(sg, s, nelems, i) {
899                 check_sync(dev, s->dma_address, s->dma_length, 0,
900                                 direction, false);
901         }
902 }
903 EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
904