dma-debug: use sg_dma_len accessor
[linux-2.6.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 static u32 nr_total_entries;
89
90 /* number of preallocated entries requested by kernel cmdline */
91 static u32 req_entries;
92
93 /* debugfs dentry's for the stuff above */
94 static struct dentry *dma_debug_dent        __read_mostly;
95 static struct dentry *global_disable_dent   __read_mostly;
96 static struct dentry *error_count_dent      __read_mostly;
97 static struct dentry *show_all_errors_dent  __read_mostly;
98 static struct dentry *show_num_errors_dent  __read_mostly;
99 static struct dentry *num_free_entries_dent __read_mostly;
100 static struct dentry *min_free_entries_dent __read_mostly;
101
102 static const char *type2name[4] = { "single", "page",
103                                     "scather-gather", "coherent" };
104
105 static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
106                                    "DMA_FROM_DEVICE", "DMA_NONE" };
107
108 /* little merge helper - remove it after the merge window */
109 #ifndef BUS_NOTIFY_UNBOUND_DRIVER
110 #define BUS_NOTIFY_UNBOUND_DRIVER 0x0005
111 #endif
112
113 /*
114  * The access to some variables in this macro is racy. We can't use atomic_t
115  * here because all these variables are exported to debugfs. Some of them even
116  * writeable. This is also the reason why a lock won't help much. But anyway,
117  * the races are no big deal. Here is why:
118  *
119  *   error_count: the addition is racy, but the worst thing that can happen is
120  *                that we don't count some errors
121  *   show_num_errors: the subtraction is racy. Also no big deal because in
122  *                    worst case this will result in one warning more in the
123  *                    system log than the user configured. This variable is
124  *                    writeable via debugfs.
125  */
126 static inline void dump_entry_trace(struct dma_debug_entry *entry)
127 {
128 #ifdef CONFIG_STACKTRACE
129         if (entry) {
130                 printk(KERN_WARNING "Mapped at:\n");
131                 print_stack_trace(&entry->stacktrace, 0);
132         }
133 #endif
134 }
135
136 #define err_printk(dev, entry, format, arg...) do {             \
137                 error_count += 1;                               \
138                 if (show_all_errors || show_num_errors > 0) {   \
139                         WARN(1, "%s %s: " format,               \
140                              dev_driver_string(dev),            \
141                              dev_name(dev) , ## arg);           \
142                         dump_entry_trace(entry);                \
143                 }                                               \
144                 if (!show_all_errors && show_num_errors > 0)    \
145                         show_num_errors -= 1;                   \
146         } while (0);
147
148 /*
149  * Hash related functions
150  *
151  * Every DMA-API request is saved into a struct dma_debug_entry. To
152  * have quick access to these structs they are stored into a hash.
153  */
154 static int hash_fn(struct dma_debug_entry *entry)
155 {
156         /*
157          * Hash function is based on the dma address.
158          * We use bits 20-27 here as the index into the hash
159          */
160         return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
161 }
162
163 /*
164  * Request exclusive access to a hash bucket for a given dma_debug_entry.
165  */
166 static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
167                                            unsigned long *flags)
168 {
169         int idx = hash_fn(entry);
170         unsigned long __flags;
171
172         spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
173         *flags = __flags;
174         return &dma_entry_hash[idx];
175 }
176
177 /*
178  * Give up exclusive access to the hash bucket
179  */
180 static void put_hash_bucket(struct hash_bucket *bucket,
181                             unsigned long *flags)
182 {
183         unsigned long __flags = *flags;
184
185         spin_unlock_irqrestore(&bucket->lock, __flags);
186 }
187
188 /*
189  * Search a given entry in the hash bucket list
190  */
191 static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket,
192                                                 struct dma_debug_entry *ref)
193 {
194         struct dma_debug_entry *entry;
195
196         list_for_each_entry(entry, &bucket->list, list) {
197                 if ((entry->dev_addr == ref->dev_addr) &&
198                     (entry->dev == ref->dev))
199                         return entry;
200         }
201
202         return NULL;
203 }
204
205 /*
206  * Add an entry to a hash bucket
207  */
208 static void hash_bucket_add(struct hash_bucket *bucket,
209                             struct dma_debug_entry *entry)
210 {
211         list_add_tail(&entry->list, &bucket->list);
212 }
213
214 /*
215  * Remove entry from a hash bucket list
216  */
217 static void hash_bucket_del(struct dma_debug_entry *entry)
218 {
219         list_del(&entry->list);
220 }
221
222 /*
223  * Dump mapping entries for debugging purposes
224  */
225 void debug_dma_dump_mappings(struct device *dev)
226 {
227         int idx;
228
229         for (idx = 0; idx < HASH_SIZE; idx++) {
230                 struct hash_bucket *bucket = &dma_entry_hash[idx];
231                 struct dma_debug_entry *entry;
232                 unsigned long flags;
233
234                 spin_lock_irqsave(&bucket->lock, flags);
235
236                 list_for_each_entry(entry, &bucket->list, list) {
237                         if (!dev || dev == entry->dev) {
238                                 dev_info(entry->dev,
239                                          "%s idx %d P=%Lx D=%Lx L=%Lx %s\n",
240                                          type2name[entry->type], idx,
241                                          (unsigned long long)entry->paddr,
242                                          entry->dev_addr, entry->size,
243                                          dir2name[entry->direction]);
244                         }
245                 }
246
247                 spin_unlock_irqrestore(&bucket->lock, flags);
248         }
249 }
250 EXPORT_SYMBOL(debug_dma_dump_mappings);
251
252 /*
253  * Wrapper function for adding an entry to the hash.
254  * This function takes care of locking itself.
255  */
256 static void add_dma_entry(struct dma_debug_entry *entry)
257 {
258         struct hash_bucket *bucket;
259         unsigned long flags;
260
261         bucket = get_hash_bucket(entry, &flags);
262         hash_bucket_add(bucket, entry);
263         put_hash_bucket(bucket, &flags);
264 }
265
266 static struct dma_debug_entry *__dma_entry_alloc(void)
267 {
268         struct dma_debug_entry *entry;
269
270         entry = list_entry(free_entries.next, struct dma_debug_entry, list);
271         list_del(&entry->list);
272         memset(entry, 0, sizeof(*entry));
273
274         num_free_entries -= 1;
275         if (num_free_entries < min_free_entries)
276                 min_free_entries = num_free_entries;
277
278         return entry;
279 }
280
281 /* struct dma_entry allocator
282  *
283  * The next two functions implement the allocator for
284  * struct dma_debug_entries.
285  */
286 static struct dma_debug_entry *dma_entry_alloc(void)
287 {
288         struct dma_debug_entry *entry = NULL;
289         unsigned long flags;
290
291         spin_lock_irqsave(&free_entries_lock, flags);
292
293         if (list_empty(&free_entries)) {
294                 printk(KERN_ERR "DMA-API: debugging out of memory "
295                                 "- disabling\n");
296                 global_disable = true;
297                 goto out;
298         }
299
300         entry = __dma_entry_alloc();
301
302 #ifdef CONFIG_STACKTRACE
303         entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
304         entry->stacktrace.entries = entry->st_entries;
305         entry->stacktrace.skip = 2;
306         save_stack_trace(&entry->stacktrace);
307 #endif
308
309 out:
310         spin_unlock_irqrestore(&free_entries_lock, flags);
311
312         return entry;
313 }
314
315 static void dma_entry_free(struct dma_debug_entry *entry)
316 {
317         unsigned long flags;
318
319         /*
320          * add to beginning of the list - this way the entries are
321          * more likely cache hot when they are reallocated.
322          */
323         spin_lock_irqsave(&free_entries_lock, flags);
324         list_add(&entry->list, &free_entries);
325         num_free_entries += 1;
326         spin_unlock_irqrestore(&free_entries_lock, flags);
327 }
328
329 int dma_debug_resize_entries(u32 num_entries)
330 {
331         int i, delta, ret = 0;
332         unsigned long flags;
333         struct dma_debug_entry *entry;
334         LIST_HEAD(tmp);
335
336         spin_lock_irqsave(&free_entries_lock, flags);
337
338         if (nr_total_entries < num_entries) {
339                 delta = num_entries - nr_total_entries;
340
341                 spin_unlock_irqrestore(&free_entries_lock, flags);
342
343                 for (i = 0; i < delta; i++) {
344                         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
345                         if (!entry)
346                                 break;
347
348                         list_add_tail(&entry->list, &tmp);
349                 }
350
351                 spin_lock_irqsave(&free_entries_lock, flags);
352
353                 list_splice(&tmp, &free_entries);
354                 nr_total_entries += i;
355                 num_free_entries += i;
356         } else {
357                 delta = nr_total_entries - num_entries;
358
359                 for (i = 0; i < delta && !list_empty(&free_entries); i++) {
360                         entry = __dma_entry_alloc();
361                         kfree(entry);
362                 }
363
364                 nr_total_entries -= i;
365         }
366
367         if (nr_total_entries != num_entries)
368                 ret = 1;
369
370         spin_unlock_irqrestore(&free_entries_lock, flags);
371
372         return ret;
373 }
374 EXPORT_SYMBOL(dma_debug_resize_entries);
375
376 /*
377  * DMA-API debugging init code
378  *
379  * The init code does two things:
380  *   1. Initialize core data structures
381  *   2. Preallocate a given number of dma_debug_entry structs
382  */
383
384 static int prealloc_memory(u32 num_entries)
385 {
386         struct dma_debug_entry *entry, *next_entry;
387         int i;
388
389         for (i = 0; i < num_entries; ++i) {
390                 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
391                 if (!entry)
392                         goto out_err;
393
394                 list_add_tail(&entry->list, &free_entries);
395         }
396
397         num_free_entries = num_entries;
398         min_free_entries = num_entries;
399
400         printk(KERN_INFO "DMA-API: preallocated %d debug entries\n",
401                         num_entries);
402
403         return 0;
404
405 out_err:
406
407         list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
408                 list_del(&entry->list);
409                 kfree(entry);
410         }
411
412         return -ENOMEM;
413 }
414
415 static int dma_debug_fs_init(void)
416 {
417         dma_debug_dent = debugfs_create_dir("dma-api", NULL);
418         if (!dma_debug_dent) {
419                 printk(KERN_ERR "DMA-API: can not create debugfs directory\n");
420                 return -ENOMEM;
421         }
422
423         global_disable_dent = debugfs_create_bool("disabled", 0444,
424                         dma_debug_dent,
425                         (u32 *)&global_disable);
426         if (!global_disable_dent)
427                 goto out_err;
428
429         error_count_dent = debugfs_create_u32("error_count", 0444,
430                         dma_debug_dent, &error_count);
431         if (!error_count_dent)
432                 goto out_err;
433
434         show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
435                         dma_debug_dent,
436                         &show_all_errors);
437         if (!show_all_errors_dent)
438                 goto out_err;
439
440         show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
441                         dma_debug_dent,
442                         &show_num_errors);
443         if (!show_num_errors_dent)
444                 goto out_err;
445
446         num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
447                         dma_debug_dent,
448                         &num_free_entries);
449         if (!num_free_entries_dent)
450                 goto out_err;
451
452         min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
453                         dma_debug_dent,
454                         &min_free_entries);
455         if (!min_free_entries_dent)
456                 goto out_err;
457
458         return 0;
459
460 out_err:
461         debugfs_remove_recursive(dma_debug_dent);
462
463         return -ENOMEM;
464 }
465
466 static int device_dma_allocations(struct device *dev)
467 {
468         struct dma_debug_entry *entry;
469         unsigned long flags;
470         int count = 0, i;
471
472         for (i = 0; i < HASH_SIZE; ++i) {
473                 spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
474                 list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
475                         if (entry->dev == dev)
476                                 count += 1;
477                 }
478                 spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
479         }
480
481         return count;
482 }
483
484 static int dma_debug_device_change(struct notifier_block *nb,
485                                     unsigned long action, void *data)
486 {
487         struct device *dev = data;
488         int count;
489
490
491         switch (action) {
492         case BUS_NOTIFY_UNBOUND_DRIVER:
493                 count = device_dma_allocations(dev);
494                 if (count == 0)
495                         break;
496                 err_printk(dev, NULL, "DMA-API: device driver has pending "
497                                 "DMA allocations while released from device "
498                                 "[count=%d]\n", count);
499                 break;
500         default:
501                 break;
502         }
503
504         return 0;
505 }
506
507 void dma_debug_add_bus(struct bus_type *bus)
508 {
509         struct notifier_block *nb;
510
511         nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
512         if (nb == NULL) {
513                 printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
514                 return;
515         }
516
517         nb->notifier_call = dma_debug_device_change;
518
519         bus_register_notifier(bus, nb);
520 }
521
522 /*
523  * Let the architectures decide how many entries should be preallocated.
524  */
525 void dma_debug_init(u32 num_entries)
526 {
527         int i;
528
529         if (global_disable)
530                 return;
531
532         for (i = 0; i < HASH_SIZE; ++i) {
533                 INIT_LIST_HEAD(&dma_entry_hash[i].list);
534                 dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
535         }
536
537         if (dma_debug_fs_init() != 0) {
538                 printk(KERN_ERR "DMA-API: error creating debugfs entries "
539                                 "- disabling\n");
540                 global_disable = true;
541
542                 return;
543         }
544
545         if (req_entries)
546                 num_entries = req_entries;
547
548         if (prealloc_memory(num_entries) != 0) {
549                 printk(KERN_ERR "DMA-API: debugging out of memory error "
550                                 "- disabled\n");
551                 global_disable = true;
552
553                 return;
554         }
555
556         nr_total_entries = num_free_entries;
557
558         printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
559 }
560
561 static __init int dma_debug_cmdline(char *str)
562 {
563         if (!str)
564                 return -EINVAL;
565
566         if (strncmp(str, "off", 3) == 0) {
567                 printk(KERN_INFO "DMA-API: debugging disabled on kernel "
568                                  "command line\n");
569                 global_disable = true;
570         }
571
572         return 0;
573 }
574
575 static __init int dma_debug_entries_cmdline(char *str)
576 {
577         int res;
578
579         if (!str)
580                 return -EINVAL;
581
582         res = get_option(&str, &req_entries);
583
584         if (!res)
585                 req_entries = 0;
586
587         return 0;
588 }
589
590 __setup("dma_debug=", dma_debug_cmdline);
591 __setup("dma_debug_entries=", dma_debug_entries_cmdline);
592
593 static void check_unmap(struct dma_debug_entry *ref)
594 {
595         struct dma_debug_entry *entry;
596         struct hash_bucket *bucket;
597         unsigned long flags;
598
599         if (dma_mapping_error(ref->dev, ref->dev_addr)) {
600                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
601                            "to free an invalid DMA memory address\n");
602                 return;
603         }
604
605         bucket = get_hash_bucket(ref, &flags);
606         entry = hash_bucket_find(bucket, ref);
607
608         if (!entry) {
609                 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
610                            "to free DMA memory it has not allocated "
611                            "[device address=0x%016llx] [size=%llu bytes]\n",
612                            ref->dev_addr, ref->size);
613                 goto out;
614         }
615
616         if (ref->size != entry->size) {
617                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
618                            "DMA memory with different size "
619                            "[device address=0x%016llx] [map size=%llu bytes] "
620                            "[unmap size=%llu bytes]\n",
621                            ref->dev_addr, entry->size, ref->size);
622         }
623
624         if (ref->type != entry->type) {
625                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
626                            "DMA memory with wrong function "
627                            "[device address=0x%016llx] [size=%llu bytes] "
628                            "[mapped as %s] [unmapped as %s]\n",
629                            ref->dev_addr, ref->size,
630                            type2name[entry->type], type2name[ref->type]);
631         } else if ((entry->type == dma_debug_coherent) &&
632                    (ref->paddr != entry->paddr)) {
633                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
634                            "DMA memory with different CPU address "
635                            "[device address=0x%016llx] [size=%llu bytes] "
636                            "[cpu alloc address=%p] [cpu free address=%p]",
637                            ref->dev_addr, ref->size,
638                            (void *)entry->paddr, (void *)ref->paddr);
639         }
640
641         if (ref->sg_call_ents && ref->type == dma_debug_sg &&
642             ref->sg_call_ents != entry->sg_call_ents) {
643                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
644                            "DMA sg list with different entry count "
645                            "[map count=%d] [unmap count=%d]\n",
646                            entry->sg_call_ents, ref->sg_call_ents);
647         }
648
649         /*
650          * This may be no bug in reality - but most implementations of the
651          * DMA API don't handle this properly, so check for it here
652          */
653         if (ref->direction != entry->direction) {
654                 err_printk(ref->dev, entry, "DMA-API: device driver frees "
655                            "DMA memory with different direction "
656                            "[device address=0x%016llx] [size=%llu bytes] "
657                            "[mapped with %s] [unmapped with %s]\n",
658                            ref->dev_addr, ref->size,
659                            dir2name[entry->direction],
660                            dir2name[ref->direction]);
661         }
662
663         hash_bucket_del(entry);
664         dma_entry_free(entry);
665
666 out:
667         put_hash_bucket(bucket, &flags);
668 }
669
670 static void check_for_stack(struct device *dev, void *addr)
671 {
672         if (object_is_on_stack(addr))
673                 err_printk(dev, NULL, "DMA-API: device driver maps memory from"
674                                 "stack [addr=%p]\n", addr);
675 }
676
677 static inline bool overlap(void *addr, u64 size, void *start, void *end)
678 {
679         void *addr2 = (char *)addr + size;
680
681         return ((addr >= start && addr < end) ||
682                 (addr2 >= start && addr2 < end) ||
683                 ((addr < start) && (addr2 >= end)));
684 }
685
686 static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
687 {
688         if (overlap(addr, size, _text, _etext) ||
689             overlap(addr, size, __start_rodata, __end_rodata))
690                 err_printk(dev, NULL, "DMA-API: device driver maps "
691                                 "memory from kernel text or rodata "
692                                 "[addr=%p] [size=%llu]\n", addr, size);
693 }
694
695 static void check_sync(struct device *dev, dma_addr_t addr,
696                        u64 size, u64 offset, int direction, bool to_cpu)
697 {
698         struct dma_debug_entry ref = {
699                 .dev            = dev,
700                 .dev_addr       = addr,
701                 .size           = size,
702                 .direction      = direction,
703         };
704         struct dma_debug_entry *entry;
705         struct hash_bucket *bucket;
706         unsigned long flags;
707
708         bucket = get_hash_bucket(&ref, &flags);
709
710         entry = hash_bucket_find(bucket, &ref);
711
712         if (!entry) {
713                 err_printk(dev, NULL, "DMA-API: device driver tries "
714                                 "to sync DMA memory it has not allocated "
715                                 "[device address=0x%016llx] [size=%llu bytes]\n",
716                                 (unsigned long long)addr, size);
717                 goto out;
718         }
719
720         if ((offset + size) > entry->size) {
721                 err_printk(dev, entry, "DMA-API: device driver syncs"
722                                 " DMA memory outside allocated range "
723                                 "[device address=0x%016llx] "
724                                 "[allocation size=%llu bytes] [sync offset=%llu] "
725                                 "[sync size=%llu]\n", entry->dev_addr, entry->size,
726                                 offset, size);
727         }
728
729         if (direction != entry->direction) {
730                 err_printk(dev, entry, "DMA-API: device driver syncs "
731                                 "DMA memory with different direction "
732                                 "[device address=0x%016llx] [size=%llu bytes] "
733                                 "[mapped with %s] [synced with %s]\n",
734                                 (unsigned long long)addr, entry->size,
735                                 dir2name[entry->direction],
736                                 dir2name[direction]);
737         }
738
739         if (entry->direction == DMA_BIDIRECTIONAL)
740                 goto out;
741
742         if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
743                       !(direction == DMA_TO_DEVICE))
744                 err_printk(dev, entry, "DMA-API: device driver syncs "
745                                 "device read-only DMA memory for cpu "
746                                 "[device address=0x%016llx] [size=%llu bytes] "
747                                 "[mapped with %s] [synced with %s]\n",
748                                 (unsigned long long)addr, entry->size,
749                                 dir2name[entry->direction],
750                                 dir2name[direction]);
751
752         if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
753                        !(direction == DMA_FROM_DEVICE))
754                 err_printk(dev, entry, "DMA-API: device driver syncs "
755                                 "device write-only DMA memory to device "
756                                 "[device address=0x%016llx] [size=%llu bytes] "
757                                 "[mapped with %s] [synced with %s]\n",
758                                 (unsigned long long)addr, entry->size,
759                                 dir2name[entry->direction],
760                                 dir2name[direction]);
761
762 out:
763         put_hash_bucket(bucket, &flags);
764
765 }
766
767 void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
768                         size_t size, int direction, dma_addr_t dma_addr,
769                         bool map_single)
770 {
771         struct dma_debug_entry *entry;
772
773         if (unlikely(global_disable))
774                 return;
775
776         if (unlikely(dma_mapping_error(dev, dma_addr)))
777                 return;
778
779         entry = dma_entry_alloc();
780         if (!entry)
781                 return;
782
783         entry->dev       = dev;
784         entry->type      = dma_debug_page;
785         entry->paddr     = page_to_phys(page) + offset;
786         entry->dev_addr  = dma_addr;
787         entry->size      = size;
788         entry->direction = direction;
789
790         if (map_single)
791                 entry->type = dma_debug_single;
792
793         if (!PageHighMem(page)) {
794                 void *addr = ((char *)page_address(page)) + offset;
795                 check_for_stack(dev, addr);
796                 check_for_illegal_area(dev, addr, size);
797         }
798
799         add_dma_entry(entry);
800 }
801 EXPORT_SYMBOL(debug_dma_map_page);
802
803 void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
804                           size_t size, int direction, bool map_single)
805 {
806         struct dma_debug_entry ref = {
807                 .type           = dma_debug_page,
808                 .dev            = dev,
809                 .dev_addr       = addr,
810                 .size           = size,
811                 .direction      = direction,
812         };
813
814         if (unlikely(global_disable))
815                 return;
816
817         if (map_single)
818                 ref.type = dma_debug_single;
819
820         check_unmap(&ref);
821 }
822 EXPORT_SYMBOL(debug_dma_unmap_page);
823
824 void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
825                       int nents, int mapped_ents, int direction)
826 {
827         struct dma_debug_entry *entry;
828         struct scatterlist *s;
829         int i;
830
831         if (unlikely(global_disable))
832                 return;
833
834         for_each_sg(sg, s, mapped_ents, i) {
835                 entry = dma_entry_alloc();
836                 if (!entry)
837                         return;
838
839                 entry->type           = dma_debug_sg;
840                 entry->dev            = dev;
841                 entry->paddr          = sg_phys(s);
842                 entry->size           = sg_dma_len(s);
843                 entry->dev_addr       = sg_dma_address(s);
844                 entry->direction      = direction;
845                 entry->sg_call_ents   = nents;
846                 entry->sg_mapped_ents = mapped_ents;
847
848                 if (!PageHighMem(sg_page(s))) {
849                         check_for_stack(dev, sg_virt(s));
850                         check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s));
851                 }
852
853                 add_dma_entry(entry);
854         }
855 }
856 EXPORT_SYMBOL(debug_dma_map_sg);
857
858 void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
859                         int nelems, int dir)
860 {
861         struct dma_debug_entry *entry;
862         struct scatterlist *s;
863         int mapped_ents = 0, i;
864         unsigned long flags;
865
866         if (unlikely(global_disable))
867                 return;
868
869         for_each_sg(sglist, s, nelems, i) {
870
871                 struct dma_debug_entry ref = {
872                         .type           = dma_debug_sg,
873                         .dev            = dev,
874                         .paddr          = sg_phys(s),
875                         .dev_addr       = sg_dma_address(s),
876                         .size           = sg_dma_len(s),
877                         .direction      = dir,
878                         .sg_call_ents   = 0,
879                 };
880
881                 if (mapped_ents && i >= mapped_ents)
882                         break;
883
884                 if (mapped_ents == 0) {
885                         struct hash_bucket *bucket;
886                         ref.sg_call_ents = nelems;
887                         bucket = get_hash_bucket(&ref, &flags);
888                         entry = hash_bucket_find(bucket, &ref);
889                         if (entry)
890                                 mapped_ents = entry->sg_mapped_ents;
891                         put_hash_bucket(bucket, &flags);
892                 }
893
894                 check_unmap(&ref);
895         }
896 }
897 EXPORT_SYMBOL(debug_dma_unmap_sg);
898
899 void debug_dma_alloc_coherent(struct device *dev, size_t size,
900                               dma_addr_t dma_addr, void *virt)
901 {
902         struct dma_debug_entry *entry;
903
904         if (unlikely(global_disable))
905                 return;
906
907         if (unlikely(virt == NULL))
908                 return;
909
910         entry = dma_entry_alloc();
911         if (!entry)
912                 return;
913
914         entry->type      = dma_debug_coherent;
915         entry->dev       = dev;
916         entry->paddr     = virt_to_phys(virt);
917         entry->size      = size;
918         entry->dev_addr  = dma_addr;
919         entry->direction = DMA_BIDIRECTIONAL;
920
921         add_dma_entry(entry);
922 }
923 EXPORT_SYMBOL(debug_dma_alloc_coherent);
924
925 void debug_dma_free_coherent(struct device *dev, size_t size,
926                          void *virt, dma_addr_t addr)
927 {
928         struct dma_debug_entry ref = {
929                 .type           = dma_debug_coherent,
930                 .dev            = dev,
931                 .paddr          = virt_to_phys(virt),
932                 .dev_addr       = addr,
933                 .size           = size,
934                 .direction      = DMA_BIDIRECTIONAL,
935         };
936
937         if (unlikely(global_disable))
938                 return;
939
940         check_unmap(&ref);
941 }
942 EXPORT_SYMBOL(debug_dma_free_coherent);
943
944 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
945                                    size_t size, int direction)
946 {
947         if (unlikely(global_disable))
948                 return;
949
950         check_sync(dev, dma_handle, size, 0, direction, true);
951 }
952 EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
953
954 void debug_dma_sync_single_for_device(struct device *dev,
955                                       dma_addr_t dma_handle, size_t size,
956                                       int direction)
957 {
958         if (unlikely(global_disable))
959                 return;
960
961         check_sync(dev, dma_handle, size, 0, direction, false);
962 }
963 EXPORT_SYMBOL(debug_dma_sync_single_for_device);
964
965 void debug_dma_sync_single_range_for_cpu(struct device *dev,
966                                          dma_addr_t dma_handle,
967                                          unsigned long offset, size_t size,
968                                          int direction)
969 {
970         if (unlikely(global_disable))
971                 return;
972
973         check_sync(dev, dma_handle, size, offset, direction, true);
974 }
975 EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
976
977 void debug_dma_sync_single_range_for_device(struct device *dev,
978                                             dma_addr_t dma_handle,
979                                             unsigned long offset,
980                                             size_t size, int direction)
981 {
982         if (unlikely(global_disable))
983                 return;
984
985         check_sync(dev, dma_handle, size, offset, direction, false);
986 }
987 EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
988
989 void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
990                                int nelems, int direction)
991 {
992         struct scatterlist *s;
993         int i;
994
995         if (unlikely(global_disable))
996                 return;
997
998         for_each_sg(sg, s, nelems, i) {
999                 check_sync(dev, sg_dma_address(s), sg_dma_len(s), 0,
1000                            direction, true);
1001         }
1002 }
1003 EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
1004
1005 void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
1006                                   int nelems, int direction)
1007 {
1008         struct scatterlist *s;
1009         int i;
1010
1011         if (unlikely(global_disable))
1012                 return;
1013
1014         for_each_sg(sg, s, nelems, i) {
1015                 check_sync(dev, sg_dma_address(s), sg_dma_len(s), 0,
1016                            direction, false);
1017         }
1018 }
1019 EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
1020