dma-debug: warn of unmapping an invalid dma address
[linux-3.10.git] / 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 static int device_dma_allocations(struct device *dev)
404 {
405         struct dma_debug_entry *entry;
406         unsigned long flags;
407         int count = 0, i;
408
409         for (i = 0; i < HASH_SIZE; ++i) {
410                 spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
411                 list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
412                         if (entry->dev == dev)
413                                 count += 1;
414                 }
415                 spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
416         }
417
418         return count;
419 }
420
421 static int dma_debug_device_change(struct notifier_block *nb,
422                                     unsigned long action, void *data)
423 {
424         struct device *dev = data;
425         int count;
426
427
428         switch (action) {
429         case BUS_NOTIFY_UNBIND_DRIVER:
430                 count = device_dma_allocations(dev);
431                 if (count == 0)
432                         break;
433                 err_printk(dev, NULL, "DMA-API: device driver has pending "
434                                 "DMA allocations while released from device "
435                                 "[count=%d]\n", count);
436                 break;
437         default:
438                 break;
439         }
440
441         return 0;
442 }
443
444 void dma_debug_add_bus(struct bus_type *bus)
445 {
446         struct notifier_block *nb;
447
448         nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
449         if (nb == NULL) {
450                 printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
451                 return;
452         }
453
454         nb->notifier_call = dma_debug_device_change;
455
456         bus_register_notifier(bus, nb);
457 }
458
459 /*
460  * Let the architectures decide how many entries should be preallocated.
461  */
462 void dma_debug_init(u32 num_entries)
463 {
464         int i;
465
466         if (global_disable)
467                 return;
468
469         for (i = 0; i < HASH_SIZE; ++i) {
470                 INIT_LIST_HEAD(&dma_entry_hash[i].list);
471                 dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
472         }
473
474         if (dma_debug_fs_init() != 0) {
475                 printk(KERN_ERR "DMA-API: error creating debugfs entries "
476                                 "- disabling\n");
477                 global_disable = true;
478
479                 return;
480         }
481
482         if (req_entries)
483                 num_entries = req_entries;
484
485         if (prealloc_memory(num_entries) != 0) {
486                 printk(KERN_ERR "DMA-API: debugging out of memory error "
487                                 "- disabled\n");
488                 global_disable = true;
489
490                 return;
491         }
492
493         printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
494 }
495
496 static __init int dma_debug_cmdline(char *str)
497 {
498         if (!str)
499                 return -EINVAL;
500
501         if (strncmp(str, "off", 3) == 0) {
502                 printk(KERN_INFO "DMA-API: debugging disabled on kernel "
503                                  "command line\n");
504                 global_disable = true;
505         }
506
507         return 0;
508 }
509
510 static __init int dma_debug_entries_cmdline(char *str)
511 {
512         int res;
513
514         if (!str)
515                 return -EINVAL;
516
517         res = get_option(&str, &req_entries);
518
519         if (!res)
520                 req_entries = 0;
521
522         return 0;
523 }
524
525 __setup("dma_debug=", dma_debug_cmdline);
526 __setup("dma_debug_entries=", dma_debug_entries_cmdline);
527
528 static void check_unmap(struct dma_debug_entry *ref)
529 {
530         struct dma_debug_entry *entry;
531         struct hash_bucket *bucket;
532         unsigned long flags;
533
534         if (dma_mapping_error(ref->dev, ref->dev_addr)) {
535                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
536                            "to free an invalid DMA memory address\n");
537                 return;
538         }
539
540         bucket = get_hash_bucket(ref, &flags);
541         entry = hash_bucket_find(bucket, ref);
542
543         if (!entry) {
544                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
545                            "to free DMA memory it has not allocated "
546                            "[device address=0x%016llx] [size=%llu bytes]\n",
547                            ref->dev_addr, ref->size);
548                 goto out;
549         }
550
551         if (ref->size != entry->size) {
552                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
553                            "DMA memory with different size "
554                            "[device address=0x%016llx] [map size=%llu bytes] "
555                            "[unmap size=%llu bytes]\n",
556                            ref->dev_addr, entry->size, ref->size);
557         }
558
559         if (ref->type != entry->type) {
560                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
561                            "DMA memory with wrong function "
562                            "[device address=0x%016llx] [size=%llu bytes] "
563                            "[mapped as %s] [unmapped as %s]\n",
564                            ref->dev_addr, ref->size,
565                            type2name[entry->type], type2name[ref->type]);
566         } else if ((entry->type == dma_debug_coherent) &&
567                    (ref->paddr != entry->paddr)) {
568                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
569                            "DMA memory with different CPU address "
570                            "[device address=0x%016llx] [size=%llu bytes] "
571                            "[cpu alloc address=%p] [cpu free address=%p]",
572                            ref->dev_addr, ref->size,
573                            (void *)entry->paddr, (void *)ref->paddr);
574         }
575
576         if (ref->sg_call_ents && ref->type == dma_debug_sg &&
577             ref->sg_call_ents != entry->sg_call_ents) {
578                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
579                            "DMA sg list with different entry count "
580                            "[map count=%d] [unmap count=%d]\n",
581                            entry->sg_call_ents, ref->sg_call_ents);
582         }
583
584         /*
585          * This may be no bug in reality - but most implementations of the
586          * DMA API don't handle this properly, so check for it here
587          */
588         if (ref->direction != entry->direction) {
589                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
590                            "DMA memory with different direction "
591                            "[device address=0x%016llx] [size=%llu bytes] "
592                            "[mapped with %s] [unmapped with %s]\n",
593                            ref->dev_addr, ref->size,
594                            dir2name[entry->direction],
595                            dir2name[ref->direction]);
596         }
597
598         hash_bucket_del(entry);
599         dma_entry_free(entry);
600
601 out:
602         put_hash_bucket(bucket, &flags);
603 }
604
605 static void check_for_stack(struct device *dev, void *addr)
606 {
607         if (object_is_on_stack(addr))
608                 err_printk(dev, NULL, "DMA-API: device driver maps memory from"
609                                 "stack [addr=%p]\n", addr);
610 }
611
612 static inline bool overlap(void *addr, u64 size, void *start, void *end)
613 {
614         void *addr2 = (char *)addr + size;
615
616         return ((addr >= start && addr < end) ||
617                 (addr2 >= start && addr2 < end) ||
618                 ((addr < start) && (addr2 >= end)));
619 }
620
621 static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
622 {
623         if (overlap(addr, size, _text, _etext) ||
624             overlap(addr, size, __start_rodata, __end_rodata))
625                 err_printk(dev, NULL, "DMA-API: device driver maps "
626                                 "memory from kernel text or rodata "
627                                 "[addr=%p] [size=%llu]\n", addr, size);
628 }
629
630 static void check_sync(struct device *dev, dma_addr_t addr,
631                        u64 size, u64 offset, int direction, bool to_cpu)
632 {
633         struct dma_debug_entry ref = {
634                 .dev            = dev,
635                 .dev_addr       = addr,
636                 .size           = size,
637                 .direction      = direction,
638         };
639         struct dma_debug_entry *entry;
640         struct hash_bucket *bucket;
641         unsigned long flags;
642
643         bucket = get_hash_bucket(&ref, &flags);
644
645         entry = hash_bucket_find(bucket, &ref);
646
647         if (!entry) {
648                 err_printk(dev, NULL, "DMA-API: device driver tries "
649                                 "to sync DMA memory it has not allocated "
650                                 "[device address=0x%016llx] [size=%llu bytes]\n",
651                                 addr, size);
652                 goto out;
653         }
654
655         if ((offset + size) > entry->size) {
656                 err_printk(dev, entry, "DMA-API: device driver syncs"
657                                 " DMA memory outside allocated range "
658                                 "[device address=0x%016llx] "
659                                 "[allocation size=%llu bytes] [sync offset=%llu] "
660                                 "[sync size=%llu]\n", entry->dev_addr, entry->size,
661                                 offset, size);
662         }
663
664         if (direction != entry->direction) {
665                 err_printk(dev, entry, "DMA-API: device driver syncs "
666                                 "DMA memory with different direction "
667                                 "[device address=0x%016llx] [size=%llu bytes] "
668                                 "[mapped with %s] [synced with %s]\n",
669                                 addr, entry->size,
670                                 dir2name[entry->direction],
671                                 dir2name[direction]);
672         }
673
674         if (entry->direction == DMA_BIDIRECTIONAL)
675                 goto out;
676
677         if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
678                       !(direction == DMA_TO_DEVICE))
679                 err_printk(dev, entry, "DMA-API: device driver syncs "
680                                 "device read-only DMA memory for cpu "
681                                 "[device address=0x%016llx] [size=%llu bytes] "
682                                 "[mapped with %s] [synced with %s]\n",
683                                 addr, entry->size,
684                                 dir2name[entry->direction],
685                                 dir2name[direction]);
686
687         if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
688                        !(direction == DMA_FROM_DEVICE))
689                 err_printk(dev, entry, "DMA-API: device driver syncs "
690                                 "device write-only DMA memory to device "
691                                 "[device address=0x%016llx] [size=%llu bytes] "
692                                 "[mapped with %s] [synced with %s]\n",
693                                 addr, entry->size,
694                                 dir2name[entry->direction],
695                                 dir2name[direction]);
696
697 out:
698         put_hash_bucket(bucket, &flags);
699
700 }
701
702 void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
703                         size_t size, int direction, dma_addr_t dma_addr,
704                         bool map_single)
705 {
706         struct dma_debug_entry *entry;
707
708         if (unlikely(global_disable))
709                 return;
710
711         if (unlikely(dma_mapping_error(dev, dma_addr)))
712                 return;
713
714         entry = dma_entry_alloc();
715         if (!entry)
716                 return;
717
718         entry->dev       = dev;
719         entry->type      = dma_debug_page;
720         entry->paddr     = page_to_phys(page) + offset;
721         entry->dev_addr  = dma_addr;
722         entry->size      = size;
723         entry->direction = direction;
724
725         if (map_single) {
726                 void *addr = ((char *)page_address(page)) + offset;
727
728                 entry->type = dma_debug_single;
729                 check_for_stack(dev, addr);
730                 check_for_illegal_area(dev, addr, size);
731         }
732
733         add_dma_entry(entry);
734 }
735 EXPORT_SYMBOL(debug_dma_map_page);
736
737 void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
738                           size_t size, int direction, bool map_single)
739 {
740         struct dma_debug_entry ref = {
741                 .type           = dma_debug_page,
742                 .dev            = dev,
743                 .dev_addr       = addr,
744                 .size           = size,
745                 .direction      = direction,
746         };
747
748         if (unlikely(global_disable))
749                 return;
750
751         if (map_single)
752                 ref.type = dma_debug_single;
753
754         check_unmap(&ref);
755 }
756 EXPORT_SYMBOL(debug_dma_unmap_page);
757
758 void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
759                       int nents, int mapped_ents, int direction)
760 {
761         struct dma_debug_entry *entry;
762         struct scatterlist *s;
763         int i;
764
765         if (unlikely(global_disable))
766                 return;
767
768         for_each_sg(sg, s, mapped_ents, i) {
769                 entry = dma_entry_alloc();
770                 if (!entry)
771                         return;
772
773                 entry->type           = dma_debug_sg;
774                 entry->dev            = dev;
775                 entry->paddr          = sg_phys(s);
776                 entry->size           = s->length;
777                 entry->dev_addr       = s->dma_address;
778                 entry->direction      = direction;
779                 entry->sg_call_ents   = nents;
780                 entry->sg_mapped_ents = mapped_ents;
781
782                 check_for_stack(dev, sg_virt(s));
783                 check_for_illegal_area(dev, sg_virt(s), s->length);
784
785                 add_dma_entry(entry);
786         }
787 }
788 EXPORT_SYMBOL(debug_dma_map_sg);
789
790 void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
791                         int nelems, int dir)
792 {
793         struct dma_debug_entry *entry;
794         struct scatterlist *s;
795         int mapped_ents = 0, i;
796         unsigned long flags;
797
798         if (unlikely(global_disable))
799                 return;
800
801         for_each_sg(sglist, s, nelems, i) {
802
803                 struct dma_debug_entry ref = {
804                         .type           = dma_debug_sg,
805                         .dev            = dev,
806                         .paddr          = sg_phys(s),
807                         .dev_addr       = s->dma_address,
808                         .size           = s->length,
809                         .direction      = dir,
810                         .sg_call_ents   = 0,
811                 };
812
813                 if (mapped_ents && i >= mapped_ents)
814                         break;
815
816                 if (mapped_ents == 0) {
817                         struct hash_bucket *bucket;
818                         ref.sg_call_ents = nelems;
819                         bucket = get_hash_bucket(&ref, &flags);
820                         entry = hash_bucket_find(bucket, &ref);
821                         if (entry)
822                                 mapped_ents = entry->sg_mapped_ents;
823                         put_hash_bucket(bucket, &flags);
824                 }
825
826                 check_unmap(&ref);
827         }
828 }
829 EXPORT_SYMBOL(debug_dma_unmap_sg);
830
831 void debug_dma_alloc_coherent(struct device *dev, size_t size,
832                               dma_addr_t dma_addr, void *virt)
833 {
834         struct dma_debug_entry *entry;
835
836         if (unlikely(global_disable))
837                 return;
838
839         if (unlikely(virt == NULL))
840                 return;
841
842         entry = dma_entry_alloc();
843         if (!entry)
844                 return;
845
846         entry->type      = dma_debug_coherent;
847         entry->dev       = dev;
848         entry->paddr     = virt_to_phys(virt);
849         entry->size      = size;
850         entry->dev_addr  = dma_addr;
851         entry->direction = DMA_BIDIRECTIONAL;
852
853         add_dma_entry(entry);
854 }
855 EXPORT_SYMBOL(debug_dma_alloc_coherent);
856
857 void debug_dma_free_coherent(struct device *dev, size_t size,
858                          void *virt, dma_addr_t addr)
859 {
860         struct dma_debug_entry ref = {
861                 .type           = dma_debug_coherent,
862                 .dev            = dev,
863                 .paddr          = virt_to_phys(virt),
864                 .dev_addr       = addr,
865                 .size           = size,
866                 .direction      = DMA_BIDIRECTIONAL,
867         };
868
869         if (unlikely(global_disable))
870                 return;
871
872         check_unmap(&ref);
873 }
874 EXPORT_SYMBOL(debug_dma_free_coherent);
875
876 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
877                                    size_t size, int direction)
878 {
879         if (unlikely(global_disable))
880                 return;
881
882         check_sync(dev, dma_handle, size, 0, direction, true);
883 }
884 EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
885
886 void debug_dma_sync_single_for_device(struct device *dev,
887                                       dma_addr_t dma_handle, size_t size,
888                                       int direction)
889 {
890         if (unlikely(global_disable))
891                 return;
892
893         check_sync(dev, dma_handle, size, 0, direction, false);
894 }
895 EXPORT_SYMBOL(debug_dma_sync_single_for_device);
896
897 void debug_dma_sync_single_range_for_cpu(struct device *dev,
898                                          dma_addr_t dma_handle,
899                                          unsigned long offset, size_t size,
900                                          int direction)
901 {
902         if (unlikely(global_disable))
903                 return;
904
905         check_sync(dev, dma_handle, size, offset, direction, true);
906 }
907 EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
908
909 void debug_dma_sync_single_range_for_device(struct device *dev,
910                                             dma_addr_t dma_handle,
911                                             unsigned long offset,
912                                             size_t size, int direction)
913 {
914         if (unlikely(global_disable))
915                 return;
916
917         check_sync(dev, dma_handle, size, offset, direction, false);
918 }
919 EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
920
921 void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
922                                int nelems, int direction)
923 {
924         struct scatterlist *s;
925         int i;
926
927         if (unlikely(global_disable))
928                 return;
929
930         for_each_sg(sg, s, nelems, i) {
931                 check_sync(dev, s->dma_address, s->dma_length, 0,
932                                 direction, true);
933         }
934 }
935 EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
936
937 void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
938                                   int nelems, int direction)
939 {
940         struct scatterlist *s;
941         int i;
942
943         if (unlikely(global_disable))
944                 return;
945
946         for_each_sg(sg, s, nelems, i) {
947                 check_sync(dev, s->dma_address, s->dma_length, 0,
948                                 direction, false);
949         }
950 }
951 EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
952