projects/linux·blob v6.4-rc2 · refs

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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2008 Advanced Micro Devices, Inc.
4 *
5 * Author: Joerg Roedel <[email protected]>
6 */
7
8#define pr_fmt(fmt) "DMA-API: " fmt
9
10#include <linux/sched/task_stack.h>
11#include <linux/scatterlist.h>
12#include <linux/dma-map-ops.h>
13#include <linux/sched/task.h>
14#include <linux/stacktrace.h>
15#include <linux/spinlock.h>
16#include <linux/vmalloc.h>
17#include <linux/debugfs.h>
18#include <linux/uaccess.h>
19#include <linux/export.h>
20#include <linux/device.h>
21#include <linux/types.h>
22#include <linux/sched.h>
23#include <linux/ctype.h>
24#include <linux/list.h>
25#include <linux/slab.h>
26#include <asm/sections.h>
27#include "debug.h"
28
29#define HASH_SIZE 16384ULL
30#define HASH_FN_SHIFT 13
31#define HASH_FN_MASK (HASH_SIZE - 1)
32
33#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
34/* If the pool runs out, add this many new entries at once */
35#define DMA_DEBUG_DYNAMIC_ENTRIES (PAGE_SIZE / sizeof(struct dma_debug_entry))
36
37enum {
38 dma_debug_single,
39 dma_debug_sg,
40 dma_debug_coherent,
41 dma_debug_resource,
42};
43
44enum map_err_types {
45 MAP_ERR_CHECK_NOT_APPLICABLE,
46 MAP_ERR_NOT_CHECKED,
47 MAP_ERR_CHECKED,
48};
49
50#define DMA_DEBUG_STACKTRACE_ENTRIES 5
51
52/**
53 * struct dma_debug_entry - track a dma_map* or dma_alloc_coherent mapping
54 * @list: node on pre-allocated free_entries list
55 * @dev: 'dev' argument to dma_map_{page|single|sg} or dma_alloc_coherent
56 * @dev_addr: dma address
57 * @size: length of the mapping
58 * @type: single, page, sg, coherent
59 * @direction: enum dma_data_direction
60 * @sg_call_ents: 'nents' from dma_map_sg
61 * @sg_mapped_ents: 'mapped_ents' from dma_map_sg
62 * @pfn: page frame of the start address
63 * @offset: offset of mapping relative to pfn
64 * @map_err_type: track whether dma_mapping_error() was checked
65 * @stacktrace: support backtraces when a violation is detected
66 */
67struct dma_debug_entry {
68 struct list_head list;
69 struct device *dev;
70 u64 dev_addr;
71 u64 size;
72 int type;
73 int direction;
74 int sg_call_ents;
75 int sg_mapped_ents;
76 unsigned long pfn;
77 size_t offset;
78 enum map_err_types map_err_type;
79#ifdef CONFIG_STACKTRACE
80 unsigned int stack_len;
81 unsigned long stack_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
82#endif
83} ____cacheline_aligned_in_smp;
84
85typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *);
86
87struct hash_bucket {
88 struct list_head list;
89 spinlock_t lock;
90};
91
92/* Hash list to save the allocated dma addresses */
93static struct hash_bucket dma_entry_hash[HASH_SIZE];
94/* List of pre-allocated dma_debug_entry's */
95static LIST_HEAD(free_entries);
96/* Lock for the list above */
97static DEFINE_SPINLOCK(free_entries_lock);
98
99/* Global disable flag - will be set in case of an error */
100static bool global_disable __read_mostly;
101
102/* Early initialization disable flag, set at the end of dma_debug_init */
103static bool dma_debug_initialized __read_mostly;
104
105static inline bool dma_debug_disabled(void)
106{
107 return global_disable || !dma_debug_initialized;
108}
109
110/* Global error count */
111static u32 error_count;
112
113/* Global error show enable*/
114static u32 show_all_errors __read_mostly;
115/* Number of errors to show */
116static u32 show_num_errors = 1;
117
118static u32 num_free_entries;
119static u32 min_free_entries;
120static u32 nr_total_entries;
121
122/* number of preallocated entries requested by kernel cmdline */
123static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
124
125/* per-driver filter related state */
126
127#define NAME_MAX_LEN 64
128
129static char current_driver_name[NAME_MAX_LEN] __read_mostly;
130static struct device_driver *current_driver __read_mostly;
131
132static DEFINE_RWLOCK(driver_name_lock);
133
134static const char *const maperr2str[] = {
135 [MAP_ERR_CHECK_NOT_APPLICABLE] = "dma map error check not applicable",
136 [MAP_ERR_NOT_CHECKED] = "dma map error not checked",
137 [MAP_ERR_CHECKED] = "dma map error checked",
138};
139
140static const char *type2name[] = {
141 [dma_debug_single] = "single",
142 [dma_debug_sg] = "scather-gather",
143 [dma_debug_coherent] = "coherent",
144 [dma_debug_resource] = "resource",
145};
146
147static const char *dir2name[] = {
148 [DMA_BIDIRECTIONAL] = "DMA_BIDIRECTIONAL",
149 [DMA_TO_DEVICE] = "DMA_TO_DEVICE",
150 [DMA_FROM_DEVICE] = "DMA_FROM_DEVICE",
151 [DMA_NONE] = "DMA_NONE",
152};
153
154/*
155 * The access to some variables in this macro is racy. We can't use atomic_t
156 * here because all these variables are exported to debugfs. Some of them even
157 * writeable. This is also the reason why a lock won't help much. But anyway,
158 * the races are no big deal. Here is why:
159 *
160 * error_count: the addition is racy, but the worst thing that can happen is
161 * that we don't count some errors
162 * show_num_errors: the subtraction is racy. Also no big deal because in
163 * worst case this will result in one warning more in the
164 * system log than the user configured. This variable is
165 * writeable via debugfs.
166 */
167static inline void dump_entry_trace(struct dma_debug_entry *entry)
168{
169#ifdef CONFIG_STACKTRACE
170 if (entry) {
171 pr_warn("Mapped at:\n");
172 stack_trace_print(entry->stack_entries, entry->stack_len, 0);
173 }
174#endif
175}
176
177static bool driver_filter(struct device *dev)
178{
179 struct device_driver *drv;
180 unsigned long flags;
181 bool ret;
182
183 /* driver filter off */
184 if (likely(!current_driver_name[0]))
185 return true;
186
187 /* driver filter on and initialized */
188 if (current_driver && dev && dev->driver == current_driver)
189 return true;
190
191 /* driver filter on, but we can't filter on a NULL device... */
192 if (!dev)
193 return false;
194
195 if (current_driver || !current_driver_name[0])
196 return false;
197
198 /* driver filter on but not yet initialized */
199 drv = dev->driver;
200 if (!drv)
201 return false;
202
203 /* lock to protect against change of current_driver_name */
204 read_lock_irqsave(&driver_name_lock, flags);
205
206 ret = false;
207 if (drv->name &&
208 strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) {
209 current_driver = drv;
210 ret = true;
211 }
212
213 read_unlock_irqrestore(&driver_name_lock, flags);
214
215 return ret;
216}
217
218#define err_printk(dev, entry, format, arg...) do { \
219 error_count += 1; \
220 if (driver_filter(dev) && \
221 (show_all_errors || show_num_errors > 0)) { \
222 WARN(1, pr_fmt("%s %s: ") format, \
223 dev ? dev_driver_string(dev) : "NULL", \
224 dev ? dev_name(dev) : "NULL", ## arg); \
225 dump_entry_trace(entry); \
226 } \
227 if (!show_all_errors && show_num_errors > 0) \
228 show_num_errors -= 1; \
229 } while (0);
230
231/*
232 * Hash related functions
233 *
234 * Every DMA-API request is saved into a struct dma_debug_entry. To
235 * have quick access to these structs they are stored into a hash.
236 */
237static int hash_fn(struct dma_debug_entry *entry)
238{
239 /*
240 * Hash function is based on the dma address.
241 * We use bits 20-27 here as the index into the hash
242 */
243 return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
244}
245
246/*
247 * Request exclusive access to a hash bucket for a given dma_debug_entry.
248 */
249static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
250 unsigned long *flags)
251 __acquires(&dma_entry_hash[idx].lock)
252{
253 int idx = hash_fn(entry);
254 unsigned long __flags;
255
256 spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
257 *flags = __flags;
258 return &dma_entry_hash[idx];
259}
260
261/*
262 * Give up exclusive access to the hash bucket
263 */
264static void put_hash_bucket(struct hash_bucket *bucket,
265 unsigned long flags)
266 __releases(&bucket->lock)
267{
268 spin_unlock_irqrestore(&bucket->lock, flags);
269}
270
271static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b)
272{
273 return ((a->dev_addr == b->dev_addr) &&
274 (a->dev == b->dev)) ? true : false;
275}
276
277static bool containing_match(struct dma_debug_entry *a,
278 struct dma_debug_entry *b)
279{
280 if (a->dev != b->dev)
281 return false;
282
283 if ((b->dev_addr <= a->dev_addr) &&
284 ((b->dev_addr + b->size) >= (a->dev_addr + a->size)))
285 return true;
286
287 return false;
288}
289
290/*
291 * Search a given entry in the hash bucket list
292 */
293static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket,
294 struct dma_debug_entry *ref,
295 match_fn match)
296{
297 struct dma_debug_entry *entry, *ret = NULL;
298 int matches = 0, match_lvl, last_lvl = -1;
299
300 list_for_each_entry(entry, &bucket->list, list) {
301 if (!match(ref, entry))
302 continue;
303
304 /*
305 * Some drivers map the same physical address multiple
306 * times. Without a hardware IOMMU this results in the
307 * same device addresses being put into the dma-debug
308 * hash multiple times too. This can result in false
309 * positives being reported. Therefore we implement a
310 * best-fit algorithm here which returns the entry from
311 * the hash which fits best to the reference value
312 * instead of the first-fit.
313 */
314 matches += 1;
315 match_lvl = 0;
316 entry->size == ref->size ? ++match_lvl : 0;
317 entry->type == ref->type ? ++match_lvl : 0;
318 entry->direction == ref->direction ? ++match_lvl : 0;
319 entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0;
320
321 if (match_lvl == 4) {
322 /* perfect-fit - return the result */
323 return entry;
324 } else if (match_lvl > last_lvl) {
325 /*
326 * We found an entry that fits better then the
327 * previous one or it is the 1st match.
328 */
329 last_lvl = match_lvl;
330 ret = entry;
331 }
332 }
333
334 /*
335 * If we have multiple matches but no perfect-fit, just return
336 * NULL.
337 */
338 ret = (matches == 1) ? ret : NULL;
339
340 return ret;
341}
342
343static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket,
344 struct dma_debug_entry *ref)
345{
346 return __hash_bucket_find(bucket, ref, exact_match);
347}
348
349static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket,
350 struct dma_debug_entry *ref,
351 unsigned long *flags)
352{
353
354 struct dma_debug_entry *entry, index = *ref;
355 int limit = min(HASH_SIZE, (index.dev_addr >> HASH_FN_SHIFT) + 1);
356
357 for (int i = 0; i < limit; i++) {
358 entry = __hash_bucket_find(*bucket, ref, containing_match);
359
360 if (entry)
361 return entry;
362
363 /*
364 * Nothing found, go back a hash bucket
365 */
366 put_hash_bucket(*bucket, *flags);
367 index.dev_addr -= (1 << HASH_FN_SHIFT);
368 *bucket = get_hash_bucket(&index, flags);
369 }
370
371 return NULL;
372}
373
374/*
375 * Add an entry to a hash bucket
376 */
377static void hash_bucket_add(struct hash_bucket *bucket,
378 struct dma_debug_entry *entry)
379{
380 list_add_tail(&entry->list, &bucket->list);
381}
382
383/*
384 * Remove entry from a hash bucket list
385 */
386static void hash_bucket_del(struct dma_debug_entry *entry)
387{
388 list_del(&entry->list);
389}
390
391static unsigned long long phys_addr(struct dma_debug_entry *entry)
392{
393 if (entry->type == dma_debug_resource)
394 return __pfn_to_phys(entry->pfn) + entry->offset;
395
396 return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset;
397}
398
399/*
400 * For each mapping (initial cacheline in the case of
401 * dma_alloc_coherent/dma_map_page, initial cacheline in each page of a
402 * scatterlist, or the cacheline specified in dma_map_single) insert
403 * into this tree using the cacheline as the key. At
404 * dma_unmap_{single|sg|page} or dma_free_coherent delete the entry. If
405 * the entry already exists at insertion time add a tag as a reference
406 * count for the overlapping mappings. For now, the overlap tracking
407 * just ensures that 'unmaps' balance 'maps' before marking the
408 * cacheline idle, but we should also be flagging overlaps as an API
409 * violation.
410 *
411 * Memory usage is mostly constrained by the maximum number of available
412 * dma-debug entries in that we need a free dma_debug_entry before
413 * inserting into the tree. In the case of dma_map_page and
414 * dma_alloc_coherent there is only one dma_debug_entry and one
415 * dma_active_cacheline entry to track per event. dma_map_sg(), on the
416 * other hand, consumes a single dma_debug_entry, but inserts 'nents'
417 * entries into the tree.
418 */
419static RADIX_TREE(dma_active_cacheline, GFP_ATOMIC);
420static DEFINE_SPINLOCK(radix_lock);
421#define ACTIVE_CACHELINE_MAX_OVERLAP ((1 << RADIX_TREE_MAX_TAGS) - 1)
422#define CACHELINE_PER_PAGE_SHIFT (PAGE_SHIFT - L1_CACHE_SHIFT)
423#define CACHELINES_PER_PAGE (1 << CACHELINE_PER_PAGE_SHIFT)
424
425static phys_addr_t to_cacheline_number(struct dma_debug_entry *entry)
426{
427 return (entry->pfn << CACHELINE_PER_PAGE_SHIFT) +
428 (entry->offset >> L1_CACHE_SHIFT);
429}
430
431static int active_cacheline_read_overlap(phys_addr_t cln)
432{
433 int overlap = 0, i;
434
435 for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--)
436 if (radix_tree_tag_get(&dma_active_cacheline, cln, i))
437 overlap |= 1 << i;
438 return overlap;
439}
440
441static int active_cacheline_set_overlap(phys_addr_t cln, int overlap)
442{
443 int i;
444
445 if (overlap > ACTIVE_CACHELINE_MAX_OVERLAP || overlap < 0)
446 return overlap;
447
448 for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--)
449 if (overlap & 1 << i)
450 radix_tree_tag_set(&dma_active_cacheline, cln, i);
451 else
452 radix_tree_tag_clear(&dma_active_cacheline, cln, i);
453
454 return overlap;
455}
456
457static void active_cacheline_inc_overlap(phys_addr_t cln)
458{
459 int overlap = active_cacheline_read_overlap(cln);
460
461 overlap = active_cacheline_set_overlap(cln, ++overlap);
462
463 /* If we overflowed the overlap counter then we're potentially
464 * leaking dma-mappings.
465 */
466 WARN_ONCE(overlap > ACTIVE_CACHELINE_MAX_OVERLAP,
467 pr_fmt("exceeded %d overlapping mappings of cacheline %pa\n"),
468 ACTIVE_CACHELINE_MAX_OVERLAP, &cln);
469}
470
471static int active_cacheline_dec_overlap(phys_addr_t cln)
472{
473 int overlap = active_cacheline_read_overlap(cln);
474
475 return active_cacheline_set_overlap(cln, --overlap);
476}
477
478static int active_cacheline_insert(struct dma_debug_entry *entry)
479{
480 phys_addr_t cln = to_cacheline_number(entry);
481 unsigned long flags;
482 int rc;
483
484 /* If the device is not writing memory then we don't have any
485 * concerns about the cpu consuming stale data. This mitigates
486 * legitimate usages of overlapping mappings.
487 */
488 if (entry->direction == DMA_TO_DEVICE)
489 return 0;
490
491 spin_lock_irqsave(&radix_lock, flags);
492 rc = radix_tree_insert(&dma_active_cacheline, cln, entry);
493 if (rc == -EEXIST)
494 active_cacheline_inc_overlap(cln);
495 spin_unlock_irqrestore(&radix_lock, flags);
496
497 return rc;
498}
499
500static void active_cacheline_remove(struct dma_debug_entry *entry)
501{
502 phys_addr_t cln = to_cacheline_number(entry);
503 unsigned long flags;
504
505 /* ...mirror the insert case */
506 if (entry->direction == DMA_TO_DEVICE)
507 return;
508
509 spin_lock_irqsave(&radix_lock, flags);
510 /* since we are counting overlaps the final put of the
511 * cacheline will occur when the overlap count is 0.
512 * active_cacheline_dec_overlap() returns -1 in that case
513 */
514 if (active_cacheline_dec_overlap(cln) < 0)
515 radix_tree_delete(&dma_active_cacheline, cln);
516 spin_unlock_irqrestore(&radix_lock, flags);
517}
518
519/*
520 * Dump mappings entries on kernel space for debugging purposes
521 */
522void debug_dma_dump_mappings(struct device *dev)
523{
524 int idx;
525 phys_addr_t cln;
526
527 for (idx = 0; idx < HASH_SIZE; idx++) {
528 struct hash_bucket *bucket = &dma_entry_hash[idx];
529 struct dma_debug_entry *entry;
530 unsigned long flags;
531
532 spin_lock_irqsave(&bucket->lock, flags);
533 list_for_each_entry(entry, &bucket->list, list) {
534 if (!dev || dev == entry->dev) {
535 cln = to_cacheline_number(entry);
536 dev_info(entry->dev,
537 "%s idx %d P=%llx N=%lx D=%llx L=%llx cln=%pa %s %s\n",
538 type2name[entry->type], idx,
539 phys_addr(entry), entry->pfn,
540 entry->dev_addr, entry->size,
541 &cln, dir2name[entry->direction],
542 maperr2str[entry->map_err_type]);
543 }
544 }
545 spin_unlock_irqrestore(&bucket->lock, flags);
546
547 cond_resched();
548 }
549}
550
551/*
552 * Dump mappings entries on user space via debugfs
553 */
554static int dump_show(struct seq_file *seq, void *v)
555{
556 int idx;
557 phys_addr_t cln;
558
559 for (idx = 0; idx < HASH_SIZE; idx++) {
560 struct hash_bucket *bucket = &dma_entry_hash[idx];
561 struct dma_debug_entry *entry;
562 unsigned long flags;
563
564 spin_lock_irqsave(&bucket->lock, flags);
565 list_for_each_entry(entry, &bucket->list, list) {
566 cln = to_cacheline_number(entry);
567 seq_printf(seq,
568 "%s %s %s idx %d P=%llx N=%lx D=%llx L=%llx cln=%pa %s %s\n",
569 dev_driver_string(entry->dev),
570 dev_name(entry->dev),
571 type2name[entry->type], idx,
572 phys_addr(entry), entry->pfn,
573 entry->dev_addr, entry->size,
574 &cln, dir2name[entry->direction],
575 maperr2str[entry->map_err_type]);
576 }
577 spin_unlock_irqrestore(&bucket->lock, flags);
578 }
579 return 0;
580}
581DEFINE_SHOW_ATTRIBUTE(dump);
582
583/*
584 * Wrapper function for adding an entry to the hash.
585 * This function takes care of locking itself.
586 */
587static void add_dma_entry(struct dma_debug_entry *entry, unsigned long attrs)
588{
589 struct hash_bucket *bucket;
590 unsigned long flags;
591 int rc;
592
593 bucket = get_hash_bucket(entry, &flags);
594 hash_bucket_add(bucket, entry);
595 put_hash_bucket(bucket, flags);
596
597 rc = active_cacheline_insert(entry);
598 if (rc == -ENOMEM) {
599 pr_err_once("cacheline tracking ENOMEM, dma-debug disabled\n");
600 global_disable = true;
601 } else if (rc == -EEXIST && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
602 err_printk(entry->dev, entry,
603 "cacheline tracking EEXIST, overlapping mappings aren't supported\n");
604 }
605}
606
607static int dma_debug_create_entries(gfp_t gfp)
608{
609 struct dma_debug_entry *entry;
610 int i;
611
612 entry = (void *)get_zeroed_page(gfp);
613 if (!entry)
614 return -ENOMEM;
615
616 for (i = 0; i < DMA_DEBUG_DYNAMIC_ENTRIES; i++)
617 list_add_tail(&entry[i].list, &free_entries);
618
619 num_free_entries += DMA_DEBUG_DYNAMIC_ENTRIES;
620 nr_total_entries += DMA_DEBUG_DYNAMIC_ENTRIES;
621
622 return 0;
623}
624
625static struct dma_debug_entry *__dma_entry_alloc(void)
626{
627 struct dma_debug_entry *entry;
628
629 entry = list_entry(free_entries.next, struct dma_debug_entry, list);
630 list_del(&entry->list);
631 memset(entry, 0, sizeof(*entry));
632
633 num_free_entries -= 1;
634 if (num_free_entries < min_free_entries)
635 min_free_entries = num_free_entries;
636
637 return entry;
638}
639
640static void __dma_entry_alloc_check_leak(void)
641{
642 u32 tmp = nr_total_entries % nr_prealloc_entries;
643
644 /* Shout each time we tick over some multiple of the initial pool */
645 if (tmp < DMA_DEBUG_DYNAMIC_ENTRIES) {
646 pr_info("dma_debug_entry pool grown to %u (%u00%%)\n",
647 nr_total_entries,
648 (nr_total_entries / nr_prealloc_entries));
649 }
650}
651
652/* struct dma_entry allocator
653 *
654 * The next two functions implement the allocator for
655 * struct dma_debug_entries.
656 */
657static struct dma_debug_entry *dma_entry_alloc(void)
658{
659 struct dma_debug_entry *entry;
660 unsigned long flags;
661
662 spin_lock_irqsave(&free_entries_lock, flags);
663 if (num_free_entries == 0) {
664 if (dma_debug_create_entries(GFP_ATOMIC)) {
665 global_disable = true;
666 spin_unlock_irqrestore(&free_entries_lock, flags);
667 pr_err("debugging out of memory - disabling\n");
668 return NULL;
669 }
670 __dma_entry_alloc_check_leak();
671 }
672
673 entry = __dma_entry_alloc();
674
675 spin_unlock_irqrestore(&free_entries_lock, flags);
676
677#ifdef CONFIG_STACKTRACE
678 entry->stack_len = stack_trace_save(entry->stack_entries,
679 ARRAY_SIZE(entry->stack_entries),
680 1);
681#endif
682 return entry;
683}
684
685static void dma_entry_free(struct dma_debug_entry *entry)
686{
687 unsigned long flags;
688
689 active_cacheline_remove(entry);
690
691 /*
692 * add to beginning of the list - this way the entries are
693 * more likely cache hot when they are reallocated.
694 */
695 spin_lock_irqsave(&free_entries_lock, flags);
696 list_add(&entry->list, &free_entries);
697 num_free_entries += 1;
698 spin_unlock_irqrestore(&free_entries_lock, flags);
699}
700
701/*
702 * DMA-API debugging init code
703 *
704 * The init code does two things:
705 * 1. Initialize core data structures
706 * 2. Preallocate a given number of dma_debug_entry structs
707 */
708
709static ssize_t filter_read(struct file *file, char __user *user_buf,
710 size_t count, loff_t *ppos)
711{
712 char buf[NAME_MAX_LEN + 1];
713 unsigned long flags;
714 int len;
715
716 if (!current_driver_name[0])
717 return 0;
718
719 /*
720 * We can't copy to userspace directly because current_driver_name can
721 * only be read under the driver_name_lock with irqs disabled. So
722 * create a temporary copy first.
723 */
724 read_lock_irqsave(&driver_name_lock, flags);
725 len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name);
726 read_unlock_irqrestore(&driver_name_lock, flags);
727
728 return simple_read_from_buffer(user_buf, count, ppos, buf, len);
729}
730
731static ssize_t filter_write(struct file *file, const char __user *userbuf,
732 size_t count, loff_t *ppos)
733{
734 char buf[NAME_MAX_LEN];
735 unsigned long flags;
736 size_t len;
737 int i;
738
739 /*
740 * We can't copy from userspace directly. Access to
741 * current_driver_name is protected with a write_lock with irqs
742 * disabled. Since copy_from_user can fault and may sleep we
743 * need to copy to temporary buffer first
744 */
745 len = min(count, (size_t)(NAME_MAX_LEN - 1));
746 if (copy_from_user(buf, userbuf, len))
747 return -EFAULT;
748
749 buf[len] = 0;
750
751 write_lock_irqsave(&driver_name_lock, flags);
752
753 /*
754 * Now handle the string we got from userspace very carefully.
755 * The rules are:
756 * - only use the first token we got
757 * - token delimiter is everything looking like a space
758 * character (' ', '\n', '\t' ...)
759 *
760 */
761 if (!isalnum(buf[0])) {
762 /*
763 * If the first character userspace gave us is not
764 * alphanumerical then assume the filter should be
765 * switched off.
766 */
767 if (current_driver_name[0])
768 pr_info("switching off dma-debug driver filter\n");
769 current_driver_name[0] = 0;
770 current_driver = NULL;
771 goto out_unlock;
772 }
773
774 /*
775 * Now parse out the first token and use it as the name for the
776 * driver to filter for.
777 */
778 for (i = 0; i < NAME_MAX_LEN - 1; ++i) {
779 current_driver_name[i] = buf[i];
780 if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0)
781 break;
782 }
783 current_driver_name[i] = 0;
784 current_driver = NULL;
785
786 pr_info("enable driver filter for driver [%s]\n",
787 current_driver_name);
788
789out_unlock:
790 write_unlock_irqrestore(&driver_name_lock, flags);
791
792 return count;
793}
794
795static const struct file_operations filter_fops = {
796 .read = filter_read,
797 .write = filter_write,
798 .llseek = default_llseek,
799};
800
801static int __init dma_debug_fs_init(void)
802{
803 struct dentry *dentry = debugfs_create_dir("dma-api", NULL);
804
805 debugfs_create_bool("disabled", 0444, dentry, &global_disable);
806 debugfs_create_u32("error_count", 0444, dentry, &error_count);
807 debugfs_create_u32("all_errors", 0644, dentry, &show_all_errors);
808 debugfs_create_u32("num_errors", 0644, dentry, &show_num_errors);
809 debugfs_create_u32("num_free_entries", 0444, dentry, &num_free_entries);
810 debugfs_create_u32("min_free_entries", 0444, dentry, &min_free_entries);
811 debugfs_create_u32("nr_total_entries", 0444, dentry, &nr_total_entries);
812 debugfs_create_file("driver_filter", 0644, dentry, NULL, &filter_fops);
813 debugfs_create_file("dump", 0444, dentry, NULL, &dump_fops);
814
815 return 0;
816}
817core_initcall_sync(dma_debug_fs_init);
818
819static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry)
820{
821 struct dma_debug_entry *entry;
822 unsigned long flags;
823 int count = 0, i;
824
825 for (i = 0; i < HASH_SIZE; ++i) {
826 spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
827 list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
828 if (entry->dev == dev) {
829 count += 1;
830 *out_entry = entry;
831 }
832 }
833 spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
834 }
835
836 return count;
837}
838
839static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data)
840{
841 struct device *dev = data;
842 struct dma_debug_entry *entry;
843 int count;
844
845 if (dma_debug_disabled())
846 return 0;
847
848 switch (action) {
849 case BUS_NOTIFY_UNBOUND_DRIVER:
850 count = device_dma_allocations(dev, &entry);
851 if (count == 0)
852 break;
853 err_printk(dev, entry, "device driver has pending "
854 "DMA allocations while released from device "
855 "[count=%d]\n"
856 "One of leaked entries details: "
857 "[device address=0x%016llx] [size=%llu bytes] "
858 "[mapped with %s] [mapped as %s]\n",
859 count, entry->dev_addr, entry->size,
860 dir2name[entry->direction], type2name[entry->type]);
861 break;
862 default:
863 break;
864 }
865
866 return 0;
867}
868
869void dma_debug_add_bus(struct bus_type *bus)
870{
871 struct notifier_block *nb;
872
873 if (dma_debug_disabled())
874 return;
875
876 nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
877 if (nb == NULL) {
878 pr_err("dma_debug_add_bus: out of memory\n");
879 return;
880 }
881
882 nb->notifier_call = dma_debug_device_change;
883
884 bus_register_notifier(bus, nb);
885}
886
887static int dma_debug_init(void)
888{
889 int i, nr_pages;
890
891 /* Do not use dma_debug_initialized here, since we really want to be
892 * called to set dma_debug_initialized
893 */
894 if (global_disable)
895 return 0;
896
897 for (i = 0; i < HASH_SIZE; ++i) {
898 INIT_LIST_HEAD(&dma_entry_hash[i].list);
899 spin_lock_init(&dma_entry_hash[i].lock);
900 }
901
902 nr_pages = DIV_ROUND_UP(nr_prealloc_entries, DMA_DEBUG_DYNAMIC_ENTRIES);
903 for (i = 0; i < nr_pages; ++i)
904 dma_debug_create_entries(GFP_KERNEL);
905 if (num_free_entries >= nr_prealloc_entries) {
906 pr_info("preallocated %d debug entries\n", nr_total_entries);
907 } else if (num_free_entries > 0) {
908 pr_warn("%d debug entries requested but only %d allocated\n",
909 nr_prealloc_entries, nr_total_entries);
910 } else {
911 pr_err("debugging out of memory error - disabled\n");
912 global_disable = true;
913
914 return 0;
915 }
916 min_free_entries = num_free_entries;
917
918 dma_debug_initialized = true;
919
920 pr_info("debugging enabled by kernel config\n");
921 return 0;
922}
923core_initcall(dma_debug_init);
924
925static __init int dma_debug_cmdline(char *str)
926{
927 if (!str)
928 return -EINVAL;
929
930 if (strncmp(str, "off", 3) == 0) {
931 pr_info("debugging disabled on kernel command line\n");
932 global_disable = true;
933 }
934
935 return 1;
936}
937
938static __init int dma_debug_entries_cmdline(char *str)
939{
940 if (!str)
941 return -EINVAL;
942 if (!get_option(&str, &nr_prealloc_entries))
943 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
944 return 1;
945}
946
947__setup("dma_debug=", dma_debug_cmdline);
948__setup("dma_debug_entries=", dma_debug_entries_cmdline);
949
950static void check_unmap(struct dma_debug_entry *ref)
951{
952 struct dma_debug_entry *entry;
953 struct hash_bucket *bucket;
954 unsigned long flags;
955
956 bucket = get_hash_bucket(ref, &flags);
957 entry = bucket_find_exact(bucket, ref);
958
959 if (!entry) {
960 /* must drop lock before calling dma_mapping_error */
961 put_hash_bucket(bucket, flags);
962
963 if (dma_mapping_error(ref->dev, ref->dev_addr)) {
964 err_printk(ref->dev, NULL,
965 "device driver tries to free an "
966 "invalid DMA memory address\n");
967 } else {
968 err_printk(ref->dev, NULL,
969 "device driver tries to free DMA "
970 "memory it has not allocated [device "
971 "address=0x%016llx] [size=%llu bytes]\n",
972 ref->dev_addr, ref->size);
973 }
974 return;
975 }
976
977 if (ref->size != entry->size) {
978 err_printk(ref->dev, entry, "device driver frees "
979 "DMA memory with different size "
980 "[device address=0x%016llx] [map size=%llu bytes] "
981 "[unmap size=%llu bytes]\n",
982 ref->dev_addr, entry->size, ref->size);
983 }
984
985 if (ref->type != entry->type) {
986 err_printk(ref->dev, entry, "device driver frees "
987 "DMA memory with wrong function "
988 "[device address=0x%016llx] [size=%llu bytes] "
989 "[mapped as %s] [unmapped as %s]\n",
990 ref->dev_addr, ref->size,
991 type2name[entry->type], type2name[ref->type]);
992 } else if ((entry->type == dma_debug_coherent) &&
993 (phys_addr(ref) != phys_addr(entry))) {
994 err_printk(ref->dev, entry, "device driver frees "
995 "DMA memory with different CPU address "
996 "[device address=0x%016llx] [size=%llu bytes] "
997 "[cpu alloc address=0x%016llx] "
998 "[cpu free address=0x%016llx]",
999 ref->dev_addr, ref->size,
1000 phys_addr(entry),
1001 phys_addr(ref));
1002 }
1003
1004 if (ref->sg_call_ents && ref->type == dma_debug_sg &&
1005 ref->sg_call_ents != entry->sg_call_ents) {
1006 err_printk(ref->dev, entry, "device driver frees "
1007 "DMA sg list with different entry count "
1008 "[map count=%d] [unmap count=%d]\n",
1009 entry->sg_call_ents, ref->sg_call_ents);
1010 }
1011
1012 /*
1013 * This may be no bug in reality - but most implementations of the
1014 * DMA API don't handle this properly, so check for it here
1015 */
1016 if (ref->direction != entry->direction) {
1017 err_printk(ref->dev, entry, "device driver frees "
1018 "DMA memory with different direction "
1019 "[device address=0x%016llx] [size=%llu bytes] "
1020 "[mapped with %s] [unmapped with %s]\n",
1021 ref->dev_addr, ref->size,
1022 dir2name[entry->direction],
1023 dir2name[ref->direction]);
1024 }
1025
1026 /*
1027 * Drivers should use dma_mapping_error() to check the returned
1028 * addresses of dma_map_single() and dma_map_page().
1029 * If not, print this warning message. See Documentation/core-api/dma-api.rst.
1030 */
1031 if (entry->map_err_type == MAP_ERR_NOT_CHECKED) {
1032 err_printk(ref->dev, entry,
1033 "device driver failed to check map error"
1034 "[device address=0x%016llx] [size=%llu bytes] "
1035 "[mapped as %s]",
1036 ref->dev_addr, ref->size,
1037 type2name[entry->type]);
1038 }
1039
1040 hash_bucket_del(entry);
1041 dma_entry_free(entry);
1042
1043 put_hash_bucket(bucket, flags);
1044}
1045
1046static void check_for_stack(struct device *dev,
1047 struct page *page, size_t offset)
1048{
1049 void *addr;
1050 struct vm_struct *stack_vm_area = task_stack_vm_area(current);
1051
1052 if (!stack_vm_area) {
1053 /* Stack is direct-mapped. */
1054 if (PageHighMem(page))
1055 return;
1056 addr = page_address(page) + offset;
1057 if (object_is_on_stack(addr))
1058 err_printk(dev, NULL, "device driver maps memory from stack [addr=%p]\n", addr);
1059 } else {
1060 /* Stack is vmalloced. */
1061 int i;
1062
1063 for (i = 0; i < stack_vm_area->nr_pages; i++) {
1064 if (page != stack_vm_area->pages[i])
1065 continue;
1066
1067 addr = (u8 *)current->stack + i * PAGE_SIZE + offset;
1068 err_printk(dev, NULL, "device driver maps memory from stack [probable addr=%p]\n", addr);
1069 break;
1070 }
1071 }
1072}
1073
1074static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
1075{
1076 if (memory_intersects(_stext, _etext, addr, len) ||
1077 memory_intersects(__start_rodata, __end_rodata, addr, len))
1078 err_printk(dev, NULL, "device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len);
1079}
1080
1081static void check_sync(struct device *dev,
1082 struct dma_debug_entry *ref,
1083 bool to_cpu)
1084{
1085 struct dma_debug_entry *entry;
1086 struct hash_bucket *bucket;
1087 unsigned long flags;
1088
1089 bucket = get_hash_bucket(ref, &flags);
1090
1091 entry = bucket_find_contain(&bucket, ref, &flags);
1092
1093 if (!entry) {
1094 err_printk(dev, NULL, "device driver tries "
1095 "to sync DMA memory it has not allocated "
1096 "[device address=0x%016llx] [size=%llu bytes]\n",
1097 (unsigned long long)ref->dev_addr, ref->size);
1098 goto out;
1099 }
1100
1101 if (ref->size > entry->size) {
1102 err_printk(dev, entry, "device driver syncs"
1103 " DMA memory outside allocated range "
1104 "[device address=0x%016llx] "
1105 "[allocation size=%llu bytes] "
1106 "[sync offset+size=%llu]\n",
1107 entry->dev_addr, entry->size,
1108 ref->size);
1109 }
1110
1111 if (entry->direction == DMA_BIDIRECTIONAL)
1112 goto out;
1113
1114 if (ref->direction != entry->direction) {
1115 err_printk(dev, entry, "device driver syncs "
1116 "DMA memory with different direction "
1117 "[device address=0x%016llx] [size=%llu bytes] "
1118 "[mapped with %s] [synced with %s]\n",
1119 (unsigned long long)ref->dev_addr, entry->size,
1120 dir2name[entry->direction],
1121 dir2name[ref->direction]);
1122 }
1123
1124 if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
1125 !(ref->direction == DMA_TO_DEVICE))
1126 err_printk(dev, entry, "device driver syncs "
1127 "device read-only DMA memory for cpu "
1128 "[device address=0x%016llx] [size=%llu bytes] "
1129 "[mapped with %s] [synced with %s]\n",
1130 (unsigned long long)ref->dev_addr, entry->size,
1131 dir2name[entry->direction],
1132 dir2name[ref->direction]);
1133
1134 if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
1135 !(ref->direction == DMA_FROM_DEVICE))
1136 err_printk(dev, entry, "device driver syncs "
1137 "device write-only DMA memory to device "
1138 "[device address=0x%016llx] [size=%llu bytes] "
1139 "[mapped with %s] [synced with %s]\n",
1140 (unsigned long long)ref->dev_addr, entry->size,
1141 dir2name[entry->direction],
1142 dir2name[ref->direction]);
1143
1144 if (ref->sg_call_ents && ref->type == dma_debug_sg &&
1145 ref->sg_call_ents != entry->sg_call_ents) {
1146 err_printk(ref->dev, entry, "device driver syncs "
1147 "DMA sg list with different entry count "
1148 "[map count=%d] [sync count=%d]\n",
1149 entry->sg_call_ents, ref->sg_call_ents);
1150 }
1151
1152out:
1153 put_hash_bucket(bucket, flags);
1154}
1155
1156static void check_sg_segment(struct device *dev, struct scatterlist *sg)
1157{
1158#ifdef CONFIG_DMA_API_DEBUG_SG
1159 unsigned int max_seg = dma_get_max_seg_size(dev);
1160 u64 start, end, boundary = dma_get_seg_boundary(dev);
1161
1162 /*
1163 * Either the driver forgot to set dma_parms appropriately, or
1164 * whoever generated the list forgot to check them.
1165 */
1166 if (sg->length > max_seg)
1167 err_printk(dev, NULL, "mapping sg segment longer than device claims to support [len=%u] [max=%u]\n",
1168 sg->length, max_seg);
1169 /*
1170 * In some cases this could potentially be the DMA API
1171 * implementation's fault, but it would usually imply that
1172 * the scatterlist was built inappropriately to begin with.
1173 */
1174 start = sg_dma_address(sg);
1175 end = start + sg_dma_len(sg) - 1;
1176 if ((start ^ end) & ~boundary)
1177 err_printk(dev, NULL, "mapping sg segment across boundary [start=0x%016llx] [end=0x%016llx] [boundary=0x%016llx]\n",
1178 start, end, boundary);
1179#endif
1180}
1181
1182void debug_dma_map_single(struct device *dev, const void *addr,
1183 unsigned long len)
1184{
1185 if (unlikely(dma_debug_disabled()))
1186 return;
1187
1188 if (!virt_addr_valid(addr))
1189 err_printk(dev, NULL, "device driver maps memory from invalid area [addr=%p] [len=%lu]\n",
1190 addr, len);
1191
1192 if (is_vmalloc_addr(addr))
1193 err_printk(dev, NULL, "device driver maps memory from vmalloc area [addr=%p] [len=%lu]\n",
1194 addr, len);
1195}
1196EXPORT_SYMBOL(debug_dma_map_single);
1197
1198void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
1199 size_t size, int direction, dma_addr_t dma_addr,
1200 unsigned long attrs)
1201{
1202 struct dma_debug_entry *entry;
1203
1204 if (unlikely(dma_debug_disabled()))
1205 return;
1206
1207 if (dma_mapping_error(dev, dma_addr))
1208 return;
1209
1210 entry = dma_entry_alloc();
1211 if (!entry)
1212 return;
1213
1214 entry->dev = dev;
1215 entry->type = dma_debug_single;
1216 entry->pfn = page_to_pfn(page);
1217 entry->offset = offset;
1218 entry->dev_addr = dma_addr;
1219 entry->size = size;
1220 entry->direction = direction;
1221 entry->map_err_type = MAP_ERR_NOT_CHECKED;
1222
1223 check_for_stack(dev, page, offset);
1224
1225 if (!PageHighMem(page)) {
1226 void *addr = page_address(page) + offset;
1227
1228 check_for_illegal_area(dev, addr, size);
1229 }
1230
1231 add_dma_entry(entry, attrs);
1232}
1233
1234void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
1235{
1236 struct dma_debug_entry ref;
1237 struct dma_debug_entry *entry;
1238 struct hash_bucket *bucket;
1239 unsigned long flags;
1240
1241 if (unlikely(dma_debug_disabled()))
1242 return;
1243
1244 ref.dev = dev;
1245 ref.dev_addr = dma_addr;
1246 bucket = get_hash_bucket(&ref, &flags);
1247
1248 list_for_each_entry(entry, &bucket->list, list) {
1249 if (!exact_match(&ref, entry))
1250 continue;
1251
1252 /*
1253 * The same physical address can be mapped multiple
1254 * times. Without a hardware IOMMU this results in the
1255 * same device addresses being put into the dma-debug
1256 * hash multiple times too. This can result in false
1257 * positives being reported. Therefore we implement a
1258 * best-fit algorithm here which updates the first entry
1259 * from the hash which fits the reference value and is
1260 * not currently listed as being checked.
1261 */
1262 if (entry->map_err_type == MAP_ERR_NOT_CHECKED) {
1263 entry->map_err_type = MAP_ERR_CHECKED;
1264 break;
1265 }
1266 }
1267
1268 put_hash_bucket(bucket, flags);
1269}
1270EXPORT_SYMBOL(debug_dma_mapping_error);
1271
1272void debug_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
1273 size_t size, int direction)
1274{
1275 struct dma_debug_entry ref = {
1276 .type = dma_debug_single,
1277 .dev = dev,
1278 .dev_addr = dma_addr,
1279 .size = size,
1280 .direction = direction,
1281 };
1282
1283 if (unlikely(dma_debug_disabled()))
1284 return;
1285 check_unmap(&ref);
1286}
1287
1288void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
1289 int nents, int mapped_ents, int direction,
1290 unsigned long attrs)
1291{
1292 struct dma_debug_entry *entry;
1293 struct scatterlist *s;
1294 int i;
1295
1296 if (unlikely(dma_debug_disabled()))
1297 return;
1298
1299 for_each_sg(sg, s, nents, i) {
1300 check_for_stack(dev, sg_page(s), s->offset);
1301 if (!PageHighMem(sg_page(s)))
1302 check_for_illegal_area(dev, sg_virt(s), s->length);
1303 }
1304
1305 for_each_sg(sg, s, mapped_ents, i) {
1306 entry = dma_entry_alloc();
1307 if (!entry)
1308 return;
1309
1310 entry->type = dma_debug_sg;
1311 entry->dev = dev;
1312 entry->pfn = page_to_pfn(sg_page(s));
1313 entry->offset = s->offset;
1314 entry->size = sg_dma_len(s);
1315 entry->dev_addr = sg_dma_address(s);
1316 entry->direction = direction;
1317 entry->sg_call_ents = nents;
1318 entry->sg_mapped_ents = mapped_ents;
1319
1320 check_sg_segment(dev, s);
1321
1322 add_dma_entry(entry, attrs);
1323 }
1324}
1325
1326static int get_nr_mapped_entries(struct device *dev,
1327 struct dma_debug_entry *ref)
1328{
1329 struct dma_debug_entry *entry;
1330 struct hash_bucket *bucket;
1331 unsigned long flags;
1332 int mapped_ents;
1333
1334 bucket = get_hash_bucket(ref, &flags);
1335 entry = bucket_find_exact(bucket, ref);
1336 mapped_ents = 0;
1337
1338 if (entry)
1339 mapped_ents = entry->sg_mapped_ents;
1340 put_hash_bucket(bucket, flags);
1341
1342 return mapped_ents;
1343}
1344
1345void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
1346 int nelems, int dir)
1347{
1348 struct scatterlist *s;
1349 int mapped_ents = 0, i;
1350
1351 if (unlikely(dma_debug_disabled()))
1352 return;
1353
1354 for_each_sg(sglist, s, nelems, i) {
1355
1356 struct dma_debug_entry ref = {
1357 .type = dma_debug_sg,
1358 .dev = dev,
1359 .pfn = page_to_pfn(sg_page(s)),
1360 .offset = s->offset,
1361 .dev_addr = sg_dma_address(s),
1362 .size = sg_dma_len(s),
1363 .direction = dir,
1364 .sg_call_ents = nelems,
1365 };
1366
1367 if (mapped_ents && i >= mapped_ents)
1368 break;
1369
1370 if (!i)
1371 mapped_ents = get_nr_mapped_entries(dev, &ref);
1372
1373 check_unmap(&ref);
1374 }
1375}
1376
1377void debug_dma_alloc_coherent(struct device *dev, size_t size,
1378 dma_addr_t dma_addr, void *virt,
1379 unsigned long attrs)
1380{
1381 struct dma_debug_entry *entry;
1382
1383 if (unlikely(dma_debug_disabled()))
1384 return;
1385
1386 if (unlikely(virt == NULL))
1387 return;
1388
1389 /* handle vmalloc and linear addresses */
1390 if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
1391 return;
1392
1393 entry = dma_entry_alloc();
1394 if (!entry)
1395 return;
1396
1397 entry->type = dma_debug_coherent;
1398 entry->dev = dev;
1399 entry->offset = offset_in_page(virt);
1400 entry->size = size;
1401 entry->dev_addr = dma_addr;
1402 entry->direction = DMA_BIDIRECTIONAL;
1403
1404 if (is_vmalloc_addr(virt))
1405 entry->pfn = vmalloc_to_pfn(virt);
1406 else
1407 entry->pfn = page_to_pfn(virt_to_page(virt));
1408
1409 add_dma_entry(entry, attrs);
1410}
1411
1412void debug_dma_free_coherent(struct device *dev, size_t size,
1413 void *virt, dma_addr_t dma_addr)
1414{
1415 struct dma_debug_entry ref = {
1416 .type = dma_debug_coherent,
1417 .dev = dev,
1418 .offset = offset_in_page(virt),
1419 .dev_addr = dma_addr,
1420 .size = size,
1421 .direction = DMA_BIDIRECTIONAL,
1422 };
1423
1424 /* handle vmalloc and linear addresses */
1425 if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt))
1426 return;
1427
1428 if (is_vmalloc_addr(virt))
1429 ref.pfn = vmalloc_to_pfn(virt);
1430 else
1431 ref.pfn = page_to_pfn(virt_to_page(virt));
1432
1433 if (unlikely(dma_debug_disabled()))
1434 return;
1435
1436 check_unmap(&ref);
1437}
1438
1439void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
1440 int direction, dma_addr_t dma_addr,
1441 unsigned long attrs)
1442{
1443 struct dma_debug_entry *entry;
1444
1445 if (unlikely(dma_debug_disabled()))
1446 return;
1447
1448 entry = dma_entry_alloc();
1449 if (!entry)
1450 return;
1451
1452 entry->type = dma_debug_resource;
1453 entry->dev = dev;
1454 entry->pfn = PHYS_PFN(addr);
1455 entry->offset = offset_in_page(addr);
1456 entry->size = size;
1457 entry->dev_addr = dma_addr;
1458 entry->direction = direction;
1459 entry->map_err_type = MAP_ERR_NOT_CHECKED;
1460
1461 add_dma_entry(entry, attrs);
1462}
1463
1464void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
1465 size_t size, int direction)
1466{
1467 struct dma_debug_entry ref = {
1468 .type = dma_debug_resource,
1469 .dev = dev,
1470 .dev_addr = dma_addr,
1471 .size = size,
1472 .direction = direction,
1473 };
1474
1475 if (unlikely(dma_debug_disabled()))
1476 return;
1477
1478 check_unmap(&ref);
1479}
1480
1481void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
1482 size_t size, int direction)
1483{
1484 struct dma_debug_entry ref;
1485
1486 if (unlikely(dma_debug_disabled()))
1487 return;
1488
1489 ref.type = dma_debug_single;
1490 ref.dev = dev;
1491 ref.dev_addr = dma_handle;
1492 ref.size = size;
1493 ref.direction = direction;
1494 ref.sg_call_ents = 0;
1495
1496 check_sync(dev, &ref, true);
1497}
1498
1499void debug_dma_sync_single_for_device(struct device *dev,
1500 dma_addr_t dma_handle, size_t size,
1501 int direction)
1502{
1503 struct dma_debug_entry ref;
1504
1505 if (unlikely(dma_debug_disabled()))
1506 return;
1507
1508 ref.type = dma_debug_single;
1509 ref.dev = dev;
1510 ref.dev_addr = dma_handle;
1511 ref.size = size;
1512 ref.direction = direction;
1513 ref.sg_call_ents = 0;
1514
1515 check_sync(dev, &ref, false);
1516}
1517
1518void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
1519 int nelems, int direction)
1520{
1521 struct scatterlist *s;
1522 int mapped_ents = 0, i;
1523
1524 if (unlikely(dma_debug_disabled()))
1525 return;
1526
1527 for_each_sg(sg, s, nelems, i) {
1528
1529 struct dma_debug_entry ref = {
1530 .type = dma_debug_sg,
1531 .dev = dev,
1532 .pfn = page_to_pfn(sg_page(s)),
1533 .offset = s->offset,
1534 .dev_addr = sg_dma_address(s),
1535 .size = sg_dma_len(s),
1536 .direction = direction,
1537 .sg_call_ents = nelems,
1538 };
1539
1540 if (!i)
1541 mapped_ents = get_nr_mapped_entries(dev, &ref);
1542
1543 if (i >= mapped_ents)
1544 break;
1545
1546 check_sync(dev, &ref, true);
1547 }
1548}
1549
1550void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
1551 int nelems, int direction)
1552{
1553 struct scatterlist *s;
1554 int mapped_ents = 0, i;
1555
1556 if (unlikely(dma_debug_disabled()))
1557 return;
1558
1559 for_each_sg(sg, s, nelems, i) {
1560
1561 struct dma_debug_entry ref = {
1562 .type = dma_debug_sg,
1563 .dev = dev,
1564 .pfn = page_to_pfn(sg_page(s)),
1565 .offset = s->offset,
1566 .dev_addr = sg_dma_address(s),
1567 .size = sg_dma_len(s),
1568 .direction = direction,
1569 .sg_call_ents = nelems,
1570 };
1571 if (!i)
1572 mapped_ents = get_nr_mapped_entries(dev, &ref);
1573
1574 if (i >= mapped_ents)
1575 break;
1576
1577 check_sync(dev, &ref, false);
1578 }
1579}
1580
1581static int __init dma_debug_driver_setup(char *str)
1582{
1583 int i;
1584
1585 for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
1586 current_driver_name[i] = *str;
1587 if (*str == 0)
1588 break;
1589 }
1590
1591 if (current_driver_name[0])
1592 pr_info("enable driver filter for driver [%s]\n",
1593 current_driver_name);
1594
1595
1596 return 1;
1597}
1598__setup("dma_debug_driver=", dma_debug_driver_setup);