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Commit | Line | Data |
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f2f45e5f JR |
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 | ||
972aa45c | 20 | #include <linux/scatterlist.h> |
2d62ece1 | 21 | #include <linux/dma-mapping.h> |
6c132d1b | 22 | #include <linux/stacktrace.h> |
f2f45e5f | 23 | #include <linux/dma-debug.h> |
30dfa90c | 24 | #include <linux/spinlock.h> |
788dcfa6 | 25 | #include <linux/debugfs.h> |
8a6fc708 | 26 | #include <linux/uaccess.h> |
2d62ece1 | 27 | #include <linux/device.h> |
f2f45e5f | 28 | #include <linux/types.h> |
2d62ece1 | 29 | #include <linux/sched.h> |
8a6fc708 | 30 | #include <linux/ctype.h> |
f2f45e5f | 31 | #include <linux/list.h> |
6bf07871 | 32 | #include <linux/slab.h> |
f2f45e5f | 33 | |
2e34bde1 JR |
34 | #include <asm/sections.h> |
35 | ||
30dfa90c JR |
36 | #define HASH_SIZE 1024ULL |
37 | #define HASH_FN_SHIFT 13 | |
38 | #define HASH_FN_MASK (HASH_SIZE - 1) | |
39 | ||
f2f45e5f JR |
40 | enum { |
41 | dma_debug_single, | |
42 | dma_debug_page, | |
43 | dma_debug_sg, | |
44 | dma_debug_coherent, | |
45 | }; | |
46 | ||
6c132d1b DW |
47 | #define DMA_DEBUG_STACKTRACE_ENTRIES 5 |
48 | ||
f2f45e5f JR |
49 | struct dma_debug_entry { |
50 | struct list_head list; | |
51 | struct device *dev; | |
52 | int type; | |
53 | phys_addr_t paddr; | |
54 | u64 dev_addr; | |
55 | u64 size; | |
56 | int direction; | |
57 | int sg_call_ents; | |
58 | int sg_mapped_ents; | |
6c132d1b DW |
59 | #ifdef CONFIG_STACKTRACE |
60 | struct stack_trace stacktrace; | |
61 | unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; | |
62 | #endif | |
f2f45e5f JR |
63 | }; |
64 | ||
30dfa90c JR |
65 | struct hash_bucket { |
66 | struct list_head list; | |
67 | spinlock_t lock; | |
2d62ece1 | 68 | } ____cacheline_aligned_in_smp; |
30dfa90c JR |
69 | |
70 | /* Hash list to save the allocated dma addresses */ | |
71 | static struct hash_bucket dma_entry_hash[HASH_SIZE]; | |
3b1e79ed JR |
72 | /* List of pre-allocated dma_debug_entry's */ |
73 | static LIST_HEAD(free_entries); | |
74 | /* Lock for the list above */ | |
75 | static DEFINE_SPINLOCK(free_entries_lock); | |
76 | ||
77 | /* Global disable flag - will be set in case of an error */ | |
78 | static bool global_disable __read_mostly; | |
79 | ||
788dcfa6 JR |
80 | /* Global error count */ |
81 | static u32 error_count; | |
82 | ||
83 | /* Global error show enable*/ | |
84 | static u32 show_all_errors __read_mostly; | |
85 | /* Number of errors to show */ | |
86 | static u32 show_num_errors = 1; | |
87 | ||
3b1e79ed JR |
88 | static u32 num_free_entries; |
89 | static u32 min_free_entries; | |
e6a1a89d | 90 | static u32 nr_total_entries; |
30dfa90c | 91 | |
59d3daaf JR |
92 | /* number of preallocated entries requested by kernel cmdline */ |
93 | static u32 req_entries; | |
94 | ||
788dcfa6 JR |
95 | /* debugfs dentry's for the stuff above */ |
96 | static struct dentry *dma_debug_dent __read_mostly; | |
97 | static struct dentry *global_disable_dent __read_mostly; | |
98 | static struct dentry *error_count_dent __read_mostly; | |
99 | static struct dentry *show_all_errors_dent __read_mostly; | |
100 | static struct dentry *show_num_errors_dent __read_mostly; | |
101 | static struct dentry *num_free_entries_dent __read_mostly; | |
102 | static struct dentry *min_free_entries_dent __read_mostly; | |
8a6fc708 | 103 | static struct dentry *filter_dent __read_mostly; |
788dcfa6 | 104 | |
2e507d84 JR |
105 | /* per-driver filter related state */ |
106 | ||
107 | #define NAME_MAX_LEN 64 | |
108 | ||
109 | static char current_driver_name[NAME_MAX_LEN] __read_mostly; | |
110 | static struct device_driver *current_driver __read_mostly; | |
111 | ||
112 | static DEFINE_RWLOCK(driver_name_lock); | |
113 | ||
2d62ece1 JR |
114 | static const char *type2name[4] = { "single", "page", |
115 | "scather-gather", "coherent" }; | |
116 | ||
117 | static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", | |
118 | "DMA_FROM_DEVICE", "DMA_NONE" }; | |
119 | ||
120 | /* | |
121 | * The access to some variables in this macro is racy. We can't use atomic_t | |
122 | * here because all these variables are exported to debugfs. Some of them even | |
123 | * writeable. This is also the reason why a lock won't help much. But anyway, | |
124 | * the races are no big deal. Here is why: | |
125 | * | |
126 | * error_count: the addition is racy, but the worst thing that can happen is | |
127 | * that we don't count some errors | |
128 | * show_num_errors: the subtraction is racy. Also no big deal because in | |
129 | * worst case this will result in one warning more in the | |
130 | * system log than the user configured. This variable is | |
131 | * writeable via debugfs. | |
132 | */ | |
6c132d1b DW |
133 | static inline void dump_entry_trace(struct dma_debug_entry *entry) |
134 | { | |
135 | #ifdef CONFIG_STACKTRACE | |
136 | if (entry) { | |
137 | printk(KERN_WARNING "Mapped at:\n"); | |
138 | print_stack_trace(&entry->stacktrace, 0); | |
139 | } | |
140 | #endif | |
141 | } | |
142 | ||
2e507d84 JR |
143 | static bool driver_filter(struct device *dev) |
144 | { | |
145 | /* driver filter off */ | |
146 | if (likely(!current_driver_name[0])) | |
147 | return true; | |
148 | ||
149 | /* driver filter on and initialized */ | |
150 | if (current_driver && dev->driver == current_driver) | |
151 | return true; | |
152 | ||
153 | /* driver filter on but not yet initialized */ | |
154 | if (!current_driver && current_driver_name[0]) { | |
155 | struct device_driver *drv = get_driver(dev->driver); | |
156 | unsigned long flags; | |
157 | bool ret = false; | |
158 | ||
159 | if (!drv) | |
160 | return false; | |
161 | ||
162 | /* lock to protect against change of current_driver_name */ | |
163 | read_lock_irqsave(&driver_name_lock, flags); | |
164 | ||
165 | if (drv->name && | |
8a6fc708 JR |
166 | strncmp(current_driver_name, drv->name, |
167 | NAME_MAX_LEN-1) == 0) { | |
2e507d84 JR |
168 | current_driver = drv; |
169 | ret = true; | |
170 | } | |
171 | ||
172 | read_unlock_irqrestore(&driver_name_lock, flags); | |
173 | put_driver(drv); | |
174 | ||
175 | return ret; | |
176 | } | |
177 | ||
178 | return false; | |
179 | } | |
180 | ||
6c132d1b | 181 | #define err_printk(dev, entry, format, arg...) do { \ |
2d62ece1 | 182 | error_count += 1; \ |
2e507d84 JR |
183 | if (driver_filter(dev) && \ |
184 | (show_all_errors || show_num_errors > 0)) { \ | |
2d62ece1 JR |
185 | WARN(1, "%s %s: " format, \ |
186 | dev_driver_string(dev), \ | |
187 | dev_name(dev) , ## arg); \ | |
6c132d1b | 188 | dump_entry_trace(entry); \ |
2d62ece1 JR |
189 | } \ |
190 | if (!show_all_errors && show_num_errors > 0) \ | |
191 | show_num_errors -= 1; \ | |
192 | } while (0); | |
193 | ||
30dfa90c JR |
194 | /* |
195 | * Hash related functions | |
196 | * | |
197 | * Every DMA-API request is saved into a struct dma_debug_entry. To | |
198 | * have quick access to these structs they are stored into a hash. | |
199 | */ | |
200 | static int hash_fn(struct dma_debug_entry *entry) | |
201 | { | |
202 | /* | |
203 | * Hash function is based on the dma address. | |
204 | * We use bits 20-27 here as the index into the hash | |
205 | */ | |
206 | return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK; | |
207 | } | |
208 | ||
209 | /* | |
210 | * Request exclusive access to a hash bucket for a given dma_debug_entry. | |
211 | */ | |
212 | static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry, | |
213 | unsigned long *flags) | |
214 | { | |
215 | int idx = hash_fn(entry); | |
216 | unsigned long __flags; | |
217 | ||
218 | spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags); | |
219 | *flags = __flags; | |
220 | return &dma_entry_hash[idx]; | |
221 | } | |
222 | ||
223 | /* | |
224 | * Give up exclusive access to the hash bucket | |
225 | */ | |
226 | static void put_hash_bucket(struct hash_bucket *bucket, | |
227 | unsigned long *flags) | |
228 | { | |
229 | unsigned long __flags = *flags; | |
230 | ||
231 | spin_unlock_irqrestore(&bucket->lock, __flags); | |
232 | } | |
233 | ||
234 | /* | |
235 | * Search a given entry in the hash bucket list | |
236 | */ | |
237 | static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket, | |
238 | struct dma_debug_entry *ref) | |
239 | { | |
240 | struct dma_debug_entry *entry; | |
241 | ||
242 | list_for_each_entry(entry, &bucket->list, list) { | |
243 | if ((entry->dev_addr == ref->dev_addr) && | |
244 | (entry->dev == ref->dev)) | |
245 | return entry; | |
246 | } | |
247 | ||
248 | return NULL; | |
249 | } | |
250 | ||
251 | /* | |
252 | * Add an entry to a hash bucket | |
253 | */ | |
254 | static void hash_bucket_add(struct hash_bucket *bucket, | |
255 | struct dma_debug_entry *entry) | |
256 | { | |
257 | list_add_tail(&entry->list, &bucket->list); | |
258 | } | |
259 | ||
260 | /* | |
261 | * Remove entry from a hash bucket list | |
262 | */ | |
263 | static void hash_bucket_del(struct dma_debug_entry *entry) | |
264 | { | |
265 | list_del(&entry->list); | |
266 | } | |
267 | ||
ac26c18b DW |
268 | /* |
269 | * Dump mapping entries for debugging purposes | |
270 | */ | |
271 | void debug_dma_dump_mappings(struct device *dev) | |
272 | { | |
273 | int idx; | |
274 | ||
275 | for (idx = 0; idx < HASH_SIZE; idx++) { | |
276 | struct hash_bucket *bucket = &dma_entry_hash[idx]; | |
277 | struct dma_debug_entry *entry; | |
278 | unsigned long flags; | |
279 | ||
280 | spin_lock_irqsave(&bucket->lock, flags); | |
281 | ||
282 | list_for_each_entry(entry, &bucket->list, list) { | |
283 | if (!dev || dev == entry->dev) { | |
284 | dev_info(entry->dev, | |
285 | "%s idx %d P=%Lx D=%Lx L=%Lx %s\n", | |
286 | type2name[entry->type], idx, | |
287 | (unsigned long long)entry->paddr, | |
288 | entry->dev_addr, entry->size, | |
289 | dir2name[entry->direction]); | |
290 | } | |
291 | } | |
292 | ||
293 | spin_unlock_irqrestore(&bucket->lock, flags); | |
294 | } | |
295 | } | |
296 | EXPORT_SYMBOL(debug_dma_dump_mappings); | |
297 | ||
30dfa90c JR |
298 | /* |
299 | * Wrapper function for adding an entry to the hash. | |
300 | * This function takes care of locking itself. | |
301 | */ | |
302 | static void add_dma_entry(struct dma_debug_entry *entry) | |
303 | { | |
304 | struct hash_bucket *bucket; | |
305 | unsigned long flags; | |
306 | ||
307 | bucket = get_hash_bucket(entry, &flags); | |
308 | hash_bucket_add(bucket, entry); | |
309 | put_hash_bucket(bucket, &flags); | |
310 | } | |
311 | ||
e6a1a89d FT |
312 | static struct dma_debug_entry *__dma_entry_alloc(void) |
313 | { | |
314 | struct dma_debug_entry *entry; | |
315 | ||
316 | entry = list_entry(free_entries.next, struct dma_debug_entry, list); | |
317 | list_del(&entry->list); | |
318 | memset(entry, 0, sizeof(*entry)); | |
319 | ||
320 | num_free_entries -= 1; | |
321 | if (num_free_entries < min_free_entries) | |
322 | min_free_entries = num_free_entries; | |
323 | ||
324 | return entry; | |
325 | } | |
326 | ||
3b1e79ed JR |
327 | /* struct dma_entry allocator |
328 | * | |
329 | * The next two functions implement the allocator for | |
330 | * struct dma_debug_entries. | |
331 | */ | |
332 | static struct dma_debug_entry *dma_entry_alloc(void) | |
333 | { | |
334 | struct dma_debug_entry *entry = NULL; | |
335 | unsigned long flags; | |
336 | ||
337 | spin_lock_irqsave(&free_entries_lock, flags); | |
338 | ||
339 | if (list_empty(&free_entries)) { | |
340 | printk(KERN_ERR "DMA-API: debugging out of memory " | |
341 | "- disabling\n"); | |
342 | global_disable = true; | |
343 | goto out; | |
344 | } | |
345 | ||
e6a1a89d | 346 | entry = __dma_entry_alloc(); |
3b1e79ed | 347 | |
6c132d1b DW |
348 | #ifdef CONFIG_STACKTRACE |
349 | entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; | |
350 | entry->stacktrace.entries = entry->st_entries; | |
351 | entry->stacktrace.skip = 2; | |
352 | save_stack_trace(&entry->stacktrace); | |
353 | #endif | |
3b1e79ed JR |
354 | |
355 | out: | |
356 | spin_unlock_irqrestore(&free_entries_lock, flags); | |
357 | ||
358 | return entry; | |
359 | } | |
360 | ||
361 | static void dma_entry_free(struct dma_debug_entry *entry) | |
362 | { | |
363 | unsigned long flags; | |
364 | ||
365 | /* | |
366 | * add to beginning of the list - this way the entries are | |
367 | * more likely cache hot when they are reallocated. | |
368 | */ | |
369 | spin_lock_irqsave(&free_entries_lock, flags); | |
370 | list_add(&entry->list, &free_entries); | |
371 | num_free_entries += 1; | |
372 | spin_unlock_irqrestore(&free_entries_lock, flags); | |
373 | } | |
374 | ||
e6a1a89d FT |
375 | int dma_debug_resize_entries(u32 num_entries) |
376 | { | |
377 | int i, delta, ret = 0; | |
378 | unsigned long flags; | |
379 | struct dma_debug_entry *entry; | |
380 | LIST_HEAD(tmp); | |
381 | ||
382 | spin_lock_irqsave(&free_entries_lock, flags); | |
383 | ||
384 | if (nr_total_entries < num_entries) { | |
385 | delta = num_entries - nr_total_entries; | |
386 | ||
387 | spin_unlock_irqrestore(&free_entries_lock, flags); | |
388 | ||
389 | for (i = 0; i < delta; i++) { | |
390 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
391 | if (!entry) | |
392 | break; | |
393 | ||
394 | list_add_tail(&entry->list, &tmp); | |
395 | } | |
396 | ||
397 | spin_lock_irqsave(&free_entries_lock, flags); | |
398 | ||
399 | list_splice(&tmp, &free_entries); | |
400 | nr_total_entries += i; | |
401 | num_free_entries += i; | |
402 | } else { | |
403 | delta = nr_total_entries - num_entries; | |
404 | ||
405 | for (i = 0; i < delta && !list_empty(&free_entries); i++) { | |
406 | entry = __dma_entry_alloc(); | |
407 | kfree(entry); | |
408 | } | |
409 | ||
410 | nr_total_entries -= i; | |
411 | } | |
412 | ||
413 | if (nr_total_entries != num_entries) | |
414 | ret = 1; | |
415 | ||
416 | spin_unlock_irqrestore(&free_entries_lock, flags); | |
417 | ||
418 | return ret; | |
419 | } | |
420 | EXPORT_SYMBOL(dma_debug_resize_entries); | |
421 | ||
6bf07871 JR |
422 | /* |
423 | * DMA-API debugging init code | |
424 | * | |
425 | * The init code does two things: | |
426 | * 1. Initialize core data structures | |
427 | * 2. Preallocate a given number of dma_debug_entry structs | |
428 | */ | |
429 | ||
430 | static int prealloc_memory(u32 num_entries) | |
431 | { | |
432 | struct dma_debug_entry *entry, *next_entry; | |
433 | int i; | |
434 | ||
435 | for (i = 0; i < num_entries; ++i) { | |
436 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
437 | if (!entry) | |
438 | goto out_err; | |
439 | ||
440 | list_add_tail(&entry->list, &free_entries); | |
441 | } | |
442 | ||
443 | num_free_entries = num_entries; | |
444 | min_free_entries = num_entries; | |
445 | ||
446 | printk(KERN_INFO "DMA-API: preallocated %d debug entries\n", | |
447 | num_entries); | |
448 | ||
449 | return 0; | |
450 | ||
451 | out_err: | |
452 | ||
453 | list_for_each_entry_safe(entry, next_entry, &free_entries, list) { | |
454 | list_del(&entry->list); | |
455 | kfree(entry); | |
456 | } | |
457 | ||
458 | return -ENOMEM; | |
459 | } | |
460 | ||
8a6fc708 JR |
461 | static ssize_t filter_read(struct file *file, char __user *user_buf, |
462 | size_t count, loff_t *ppos) | |
463 | { | |
464 | unsigned long flags; | |
465 | char buf[NAME_MAX_LEN + 1]; | |
466 | int len; | |
467 | ||
468 | if (!current_driver_name[0]) | |
469 | return 0; | |
470 | ||
471 | /* | |
472 | * We can't copy to userspace directly because current_driver_name can | |
473 | * only be read under the driver_name_lock with irqs disabled. So | |
474 | * create a temporary copy first. | |
475 | */ | |
476 | read_lock_irqsave(&driver_name_lock, flags); | |
477 | len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name); | |
478 | read_unlock_irqrestore(&driver_name_lock, flags); | |
479 | ||
480 | return simple_read_from_buffer(user_buf, count, ppos, buf, len); | |
481 | } | |
482 | ||
483 | static ssize_t filter_write(struct file *file, const char __user *userbuf, | |
484 | size_t count, loff_t *ppos) | |
485 | { | |
486 | unsigned long flags; | |
487 | char buf[NAME_MAX_LEN]; | |
488 | size_t len = NAME_MAX_LEN - 1; | |
489 | int i; | |
490 | ||
491 | /* | |
492 | * We can't copy from userspace directly. Access to | |
493 | * current_driver_name is protected with a write_lock with irqs | |
494 | * disabled. Since copy_from_user can fault and may sleep we | |
495 | * need to copy to temporary buffer first | |
496 | */ | |
497 | len = min(count, len); | |
498 | if (copy_from_user(buf, userbuf, len)) | |
499 | return -EFAULT; | |
500 | ||
501 | buf[len] = 0; | |
502 | ||
503 | write_lock_irqsave(&driver_name_lock, flags); | |
504 | ||
505 | /* Now handle the string we got from userspace very carefully. | |
506 | * The rules are: | |
507 | * - only use the first token we got | |
508 | * - token delimiter is everything looking like a space | |
509 | * character (' ', '\n', '\t' ...) | |
510 | * | |
511 | */ | |
512 | if (!isalnum(buf[0])) { | |
513 | /* | |
514 | If the first character userspace gave us is not | |
515 | * alphanumerical then assume the filter should be | |
516 | * switched off. | |
517 | */ | |
518 | if (current_driver_name[0]) | |
519 | printk(KERN_INFO "DMA-API: switching off dma-debug " | |
520 | "driver filter\n"); | |
521 | current_driver_name[0] = 0; | |
522 | current_driver = NULL; | |
523 | goto out_unlock; | |
524 | } | |
525 | ||
526 | /* | |
527 | * Now parse out the first token and use it as the name for the | |
528 | * driver to filter for. | |
529 | */ | |
530 | for (i = 0; i < NAME_MAX_LEN; ++i) { | |
531 | current_driver_name[i] = buf[i]; | |
532 | if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0) | |
533 | break; | |
534 | } | |
535 | current_driver_name[i] = 0; | |
536 | current_driver = NULL; | |
537 | ||
538 | printk(KERN_INFO "DMA-API: enable driver filter for driver [%s]\n", | |
539 | current_driver_name); | |
540 | ||
541 | out_unlock: | |
542 | write_unlock_irqrestore(&driver_name_lock, flags); | |
543 | ||
544 | return count; | |
545 | } | |
546 | ||
547 | const struct file_operations filter_fops = { | |
548 | .read = filter_read, | |
549 | .write = filter_write, | |
550 | }; | |
551 | ||
788dcfa6 JR |
552 | static int dma_debug_fs_init(void) |
553 | { | |
554 | dma_debug_dent = debugfs_create_dir("dma-api", NULL); | |
555 | if (!dma_debug_dent) { | |
556 | printk(KERN_ERR "DMA-API: can not create debugfs directory\n"); | |
557 | return -ENOMEM; | |
558 | } | |
559 | ||
560 | global_disable_dent = debugfs_create_bool("disabled", 0444, | |
561 | dma_debug_dent, | |
562 | (u32 *)&global_disable); | |
563 | if (!global_disable_dent) | |
564 | goto out_err; | |
565 | ||
566 | error_count_dent = debugfs_create_u32("error_count", 0444, | |
567 | dma_debug_dent, &error_count); | |
568 | if (!error_count_dent) | |
569 | goto out_err; | |
570 | ||
571 | show_all_errors_dent = debugfs_create_u32("all_errors", 0644, | |
572 | dma_debug_dent, | |
573 | &show_all_errors); | |
574 | if (!show_all_errors_dent) | |
575 | goto out_err; | |
576 | ||
577 | show_num_errors_dent = debugfs_create_u32("num_errors", 0644, | |
578 | dma_debug_dent, | |
579 | &show_num_errors); | |
580 | if (!show_num_errors_dent) | |
581 | goto out_err; | |
582 | ||
583 | num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444, | |
584 | dma_debug_dent, | |
585 | &num_free_entries); | |
586 | if (!num_free_entries_dent) | |
587 | goto out_err; | |
588 | ||
589 | min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444, | |
590 | dma_debug_dent, | |
591 | &min_free_entries); | |
592 | if (!min_free_entries_dent) | |
593 | goto out_err; | |
594 | ||
8a6fc708 JR |
595 | filter_dent = debugfs_create_file("driver_filter", 0644, |
596 | dma_debug_dent, NULL, &filter_fops); | |
597 | if (!filter_dent) | |
598 | goto out_err; | |
599 | ||
788dcfa6 JR |
600 | return 0; |
601 | ||
602 | out_err: | |
603 | debugfs_remove_recursive(dma_debug_dent); | |
604 | ||
605 | return -ENOMEM; | |
606 | } | |
607 | ||
41531c8f JR |
608 | void dma_debug_add_bus(struct bus_type *bus) |
609 | { | |
314eeac9 | 610 | /* FIXME: register notifier */ |
41531c8f | 611 | } |
788dcfa6 | 612 | |
6bf07871 JR |
613 | /* |
614 | * Let the architectures decide how many entries should be preallocated. | |
615 | */ | |
616 | void dma_debug_init(u32 num_entries) | |
617 | { | |
618 | int i; | |
619 | ||
620 | if (global_disable) | |
621 | return; | |
622 | ||
623 | for (i = 0; i < HASH_SIZE; ++i) { | |
624 | INIT_LIST_HEAD(&dma_entry_hash[i].list); | |
625 | dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED; | |
626 | } | |
627 | ||
788dcfa6 JR |
628 | if (dma_debug_fs_init() != 0) { |
629 | printk(KERN_ERR "DMA-API: error creating debugfs entries " | |
630 | "- disabling\n"); | |
631 | global_disable = true; | |
632 | ||
633 | return; | |
634 | } | |
635 | ||
59d3daaf JR |
636 | if (req_entries) |
637 | num_entries = req_entries; | |
638 | ||
6bf07871 JR |
639 | if (prealloc_memory(num_entries) != 0) { |
640 | printk(KERN_ERR "DMA-API: debugging out of memory error " | |
641 | "- disabled\n"); | |
642 | global_disable = true; | |
643 | ||
644 | return; | |
645 | } | |
646 | ||
e6a1a89d FT |
647 | nr_total_entries = num_free_entries; |
648 | ||
6bf07871 JR |
649 | printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n"); |
650 | } | |
651 | ||
59d3daaf JR |
652 | static __init int dma_debug_cmdline(char *str) |
653 | { | |
654 | if (!str) | |
655 | return -EINVAL; | |
656 | ||
657 | if (strncmp(str, "off", 3) == 0) { | |
658 | printk(KERN_INFO "DMA-API: debugging disabled on kernel " | |
659 | "command line\n"); | |
660 | global_disable = true; | |
661 | } | |
662 | ||
663 | return 0; | |
664 | } | |
665 | ||
666 | static __init int dma_debug_entries_cmdline(char *str) | |
667 | { | |
668 | int res; | |
669 | ||
670 | if (!str) | |
671 | return -EINVAL; | |
672 | ||
673 | res = get_option(&str, &req_entries); | |
674 | ||
675 | if (!res) | |
676 | req_entries = 0; | |
677 | ||
678 | return 0; | |
679 | } | |
680 | ||
681 | __setup("dma_debug=", dma_debug_cmdline); | |
682 | __setup("dma_debug_entries=", dma_debug_entries_cmdline); | |
683 | ||
2d62ece1 JR |
684 | static void check_unmap(struct dma_debug_entry *ref) |
685 | { | |
686 | struct dma_debug_entry *entry; | |
687 | struct hash_bucket *bucket; | |
688 | unsigned long flags; | |
689 | ||
35d40952 FT |
690 | if (dma_mapping_error(ref->dev, ref->dev_addr)) { |
691 | err_printk(ref->dev, NULL, "DMA-API: device driver tries " | |
692 | "to free an invalid DMA memory address\n"); | |
2d62ece1 | 693 | return; |
35d40952 | 694 | } |
2d62ece1 JR |
695 | |
696 | bucket = get_hash_bucket(ref, &flags); | |
697 | entry = hash_bucket_find(bucket, ref); | |
698 | ||
699 | if (!entry) { | |
6c132d1b | 700 | err_printk(ref->dev, NULL, "DMA-API: device driver tries " |
2d62ece1 JR |
701 | "to free DMA memory it has not allocated " |
702 | "[device address=0x%016llx] [size=%llu bytes]\n", | |
703 | ref->dev_addr, ref->size); | |
704 | goto out; | |
705 | } | |
706 | ||
707 | if (ref->size != entry->size) { | |
6c132d1b | 708 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece1 JR |
709 | "DMA memory with different size " |
710 | "[device address=0x%016llx] [map size=%llu bytes] " | |
711 | "[unmap size=%llu bytes]\n", | |
712 | ref->dev_addr, entry->size, ref->size); | |
713 | } | |
714 | ||
715 | if (ref->type != entry->type) { | |
6c132d1b | 716 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece1 JR |
717 | "DMA memory with wrong function " |
718 | "[device address=0x%016llx] [size=%llu bytes] " | |
719 | "[mapped as %s] [unmapped as %s]\n", | |
720 | ref->dev_addr, ref->size, | |
721 | type2name[entry->type], type2name[ref->type]); | |
722 | } else if ((entry->type == dma_debug_coherent) && | |
723 | (ref->paddr != entry->paddr)) { | |
6c132d1b | 724 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece1 JR |
725 | "DMA memory with different CPU address " |
726 | "[device address=0x%016llx] [size=%llu bytes] " | |
727 | "[cpu alloc address=%p] [cpu free address=%p]", | |
728 | ref->dev_addr, ref->size, | |
729 | (void *)entry->paddr, (void *)ref->paddr); | |
730 | } | |
731 | ||
732 | if (ref->sg_call_ents && ref->type == dma_debug_sg && | |
733 | ref->sg_call_ents != entry->sg_call_ents) { | |
6c132d1b | 734 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece1 JR |
735 | "DMA sg list with different entry count " |
736 | "[map count=%d] [unmap count=%d]\n", | |
737 | entry->sg_call_ents, ref->sg_call_ents); | |
738 | } | |
739 | ||
740 | /* | |
741 | * This may be no bug in reality - but most implementations of the | |
742 | * DMA API don't handle this properly, so check for it here | |
743 | */ | |
744 | if (ref->direction != entry->direction) { | |
6c132d1b | 745 | err_printk(ref->dev, entry, "DMA-API: device driver frees " |
2d62ece1 JR |
746 | "DMA memory with different direction " |
747 | "[device address=0x%016llx] [size=%llu bytes] " | |
748 | "[mapped with %s] [unmapped with %s]\n", | |
749 | ref->dev_addr, ref->size, | |
750 | dir2name[entry->direction], | |
751 | dir2name[ref->direction]); | |
752 | } | |
753 | ||
754 | hash_bucket_del(entry); | |
755 | dma_entry_free(entry); | |
756 | ||
757 | out: | |
758 | put_hash_bucket(bucket, &flags); | |
759 | } | |
760 | ||
761 | static void check_for_stack(struct device *dev, void *addr) | |
762 | { | |
763 | if (object_is_on_stack(addr)) | |
6c132d1b DW |
764 | err_printk(dev, NULL, "DMA-API: device driver maps memory from" |
765 | "stack [addr=%p]\n", addr); | |
2d62ece1 JR |
766 | } |
767 | ||
2e34bde1 JR |
768 | static inline bool overlap(void *addr, u64 size, void *start, void *end) |
769 | { | |
770 | void *addr2 = (char *)addr + size; | |
771 | ||
772 | return ((addr >= start && addr < end) || | |
773 | (addr2 >= start && addr2 < end) || | |
774 | ((addr < start) && (addr2 >= end))); | |
775 | } | |
776 | ||
777 | static void check_for_illegal_area(struct device *dev, void *addr, u64 size) | |
778 | { | |
779 | if (overlap(addr, size, _text, _etext) || | |
780 | overlap(addr, size, __start_rodata, __end_rodata)) | |
781 | err_printk(dev, NULL, "DMA-API: device driver maps " | |
782 | "memory from kernel text or rodata " | |
783 | "[addr=%p] [size=%llu]\n", addr, size); | |
784 | } | |
785 | ||
2d62ece1 JR |
786 | static void check_sync(struct device *dev, dma_addr_t addr, |
787 | u64 size, u64 offset, int direction, bool to_cpu) | |
788 | { | |
789 | struct dma_debug_entry ref = { | |
790 | .dev = dev, | |
791 | .dev_addr = addr, | |
792 | .size = size, | |
793 | .direction = direction, | |
794 | }; | |
795 | struct dma_debug_entry *entry; | |
796 | struct hash_bucket *bucket; | |
797 | unsigned long flags; | |
798 | ||
799 | bucket = get_hash_bucket(&ref, &flags); | |
800 | ||
801 | entry = hash_bucket_find(bucket, &ref); | |
802 | ||
803 | if (!entry) { | |
6c132d1b | 804 | err_printk(dev, NULL, "DMA-API: device driver tries " |
2d62ece1 JR |
805 | "to sync DMA memory it has not allocated " |
806 | "[device address=0x%016llx] [size=%llu bytes]\n", | |
93c36ed8 | 807 | (unsigned long long)addr, size); |
2d62ece1 JR |
808 | goto out; |
809 | } | |
810 | ||
811 | if ((offset + size) > entry->size) { | |
6c132d1b | 812 | err_printk(dev, entry, "DMA-API: device driver syncs" |
2d62ece1 JR |
813 | " DMA memory outside allocated range " |
814 | "[device address=0x%016llx] " | |
815 | "[allocation size=%llu bytes] [sync offset=%llu] " | |
816 | "[sync size=%llu]\n", entry->dev_addr, entry->size, | |
817 | offset, size); | |
818 | } | |
819 | ||
820 | if (direction != entry->direction) { | |
6c132d1b | 821 | err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece1 JR |
822 | "DMA memory with different direction " |
823 | "[device address=0x%016llx] [size=%llu bytes] " | |
824 | "[mapped with %s] [synced with %s]\n", | |
93c36ed8 | 825 | (unsigned long long)addr, entry->size, |
2d62ece1 JR |
826 | dir2name[entry->direction], |
827 | dir2name[direction]); | |
828 | } | |
829 | ||
830 | if (entry->direction == DMA_BIDIRECTIONAL) | |
831 | goto out; | |
832 | ||
833 | if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) && | |
834 | !(direction == DMA_TO_DEVICE)) | |
6c132d1b | 835 | err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece1 JR |
836 | "device read-only DMA memory for cpu " |
837 | "[device address=0x%016llx] [size=%llu bytes] " | |
838 | "[mapped with %s] [synced with %s]\n", | |
93c36ed8 | 839 | (unsigned long long)addr, entry->size, |
2d62ece1 JR |
840 | dir2name[entry->direction], |
841 | dir2name[direction]); | |
842 | ||
843 | if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) && | |
844 | !(direction == DMA_FROM_DEVICE)) | |
6c132d1b | 845 | err_printk(dev, entry, "DMA-API: device driver syncs " |
2d62ece1 JR |
846 | "device write-only DMA memory to device " |
847 | "[device address=0x%016llx] [size=%llu bytes] " | |
848 | "[mapped with %s] [synced with %s]\n", | |
93c36ed8 | 849 | (unsigned long long)addr, entry->size, |
2d62ece1 JR |
850 | dir2name[entry->direction], |
851 | dir2name[direction]); | |
852 | ||
853 | out: | |
854 | put_hash_bucket(bucket, &flags); | |
855 | ||
856 | } | |
857 | ||
f62bc980 JR |
858 | void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, |
859 | size_t size, int direction, dma_addr_t dma_addr, | |
860 | bool map_single) | |
861 | { | |
862 | struct dma_debug_entry *entry; | |
863 | ||
864 | if (unlikely(global_disable)) | |
865 | return; | |
866 | ||
867 | if (unlikely(dma_mapping_error(dev, dma_addr))) | |
868 | return; | |
869 | ||
870 | entry = dma_entry_alloc(); | |
871 | if (!entry) | |
872 | return; | |
873 | ||
874 | entry->dev = dev; | |
875 | entry->type = dma_debug_page; | |
876 | entry->paddr = page_to_phys(page) + offset; | |
877 | entry->dev_addr = dma_addr; | |
878 | entry->size = size; | |
879 | entry->direction = direction; | |
880 | ||
9537a48e | 881 | if (map_single) |
f62bc980 | 882 | entry->type = dma_debug_single; |
9537a48e JR |
883 | |
884 | if (!PageHighMem(page)) { | |
885 | void *addr = ((char *)page_address(page)) + offset; | |
2e34bde1 JR |
886 | check_for_stack(dev, addr); |
887 | check_for_illegal_area(dev, addr, size); | |
f62bc980 JR |
888 | } |
889 | ||
890 | add_dma_entry(entry); | |
891 | } | |
892 | EXPORT_SYMBOL(debug_dma_map_page); | |
893 | ||
894 | void debug_dma_unmap_page(struct device *dev, dma_addr_t addr, | |
895 | size_t size, int direction, bool map_single) | |
896 | { | |
897 | struct dma_debug_entry ref = { | |
898 | .type = dma_debug_page, | |
899 | .dev = dev, | |
900 | .dev_addr = addr, | |
901 | .size = size, | |
902 | .direction = direction, | |
903 | }; | |
904 | ||
905 | if (unlikely(global_disable)) | |
906 | return; | |
907 | ||
908 | if (map_single) | |
909 | ref.type = dma_debug_single; | |
910 | ||
911 | check_unmap(&ref); | |
912 | } | |
913 | EXPORT_SYMBOL(debug_dma_unmap_page); | |
914 | ||
972aa45c JR |
915 | void debug_dma_map_sg(struct device *dev, struct scatterlist *sg, |
916 | int nents, int mapped_ents, int direction) | |
917 | { | |
918 | struct dma_debug_entry *entry; | |
919 | struct scatterlist *s; | |
920 | int i; | |
921 | ||
922 | if (unlikely(global_disable)) | |
923 | return; | |
924 | ||
925 | for_each_sg(sg, s, mapped_ents, i) { | |
926 | entry = dma_entry_alloc(); | |
927 | if (!entry) | |
928 | return; | |
929 | ||
930 | entry->type = dma_debug_sg; | |
931 | entry->dev = dev; | |
932 | entry->paddr = sg_phys(s); | |
933 | entry->size = s->length; | |
934 | entry->dev_addr = s->dma_address; | |
935 | entry->direction = direction; | |
936 | entry->sg_call_ents = nents; | |
937 | entry->sg_mapped_ents = mapped_ents; | |
938 | ||
9537a48e JR |
939 | if (!PageHighMem(sg_page(s))) { |
940 | check_for_stack(dev, sg_virt(s)); | |
941 | check_for_illegal_area(dev, sg_virt(s), s->length); | |
942 | } | |
972aa45c JR |
943 | |
944 | add_dma_entry(entry); | |
945 | } | |
946 | } | |
947 | EXPORT_SYMBOL(debug_dma_map_sg); | |
948 | ||
949 | void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, | |
950 | int nelems, int dir) | |
951 | { | |
952 | struct dma_debug_entry *entry; | |
953 | struct scatterlist *s; | |
954 | int mapped_ents = 0, i; | |
955 | unsigned long flags; | |
956 | ||
957 | if (unlikely(global_disable)) | |
958 | return; | |
959 | ||
960 | for_each_sg(sglist, s, nelems, i) { | |
961 | ||
962 | struct dma_debug_entry ref = { | |
963 | .type = dma_debug_sg, | |
964 | .dev = dev, | |
965 | .paddr = sg_phys(s), | |
966 | .dev_addr = s->dma_address, | |
967 | .size = s->length, | |
968 | .direction = dir, | |
969 | .sg_call_ents = 0, | |
970 | }; | |
971 | ||
972 | if (mapped_ents && i >= mapped_ents) | |
973 | break; | |
974 | ||
975 | if (mapped_ents == 0) { | |
976 | struct hash_bucket *bucket; | |
977 | ref.sg_call_ents = nelems; | |
978 | bucket = get_hash_bucket(&ref, &flags); | |
979 | entry = hash_bucket_find(bucket, &ref); | |
980 | if (entry) | |
981 | mapped_ents = entry->sg_mapped_ents; | |
982 | put_hash_bucket(bucket, &flags); | |
983 | } | |
984 | ||
985 | check_unmap(&ref); | |
986 | } | |
987 | } | |
988 | EXPORT_SYMBOL(debug_dma_unmap_sg); | |
989 | ||
6bfd4498 JR |
990 | void debug_dma_alloc_coherent(struct device *dev, size_t size, |
991 | dma_addr_t dma_addr, void *virt) | |
992 | { | |
993 | struct dma_debug_entry *entry; | |
994 | ||
995 | if (unlikely(global_disable)) | |
996 | return; | |
997 | ||
998 | if (unlikely(virt == NULL)) | |
999 | return; | |
1000 | ||
1001 | entry = dma_entry_alloc(); | |
1002 | if (!entry) | |
1003 | return; | |
1004 | ||
1005 | entry->type = dma_debug_coherent; | |
1006 | entry->dev = dev; | |
1007 | entry->paddr = virt_to_phys(virt); | |
1008 | entry->size = size; | |
1009 | entry->dev_addr = dma_addr; | |
1010 | entry->direction = DMA_BIDIRECTIONAL; | |
1011 | ||
1012 | add_dma_entry(entry); | |
1013 | } | |
1014 | EXPORT_SYMBOL(debug_dma_alloc_coherent); | |
1015 | ||
1016 | void debug_dma_free_coherent(struct device *dev, size_t size, | |
1017 | void *virt, dma_addr_t addr) | |
1018 | { | |
1019 | struct dma_debug_entry ref = { | |
1020 | .type = dma_debug_coherent, | |
1021 | .dev = dev, | |
1022 | .paddr = virt_to_phys(virt), | |
1023 | .dev_addr = addr, | |
1024 | .size = size, | |
1025 | .direction = DMA_BIDIRECTIONAL, | |
1026 | }; | |
1027 | ||
1028 | if (unlikely(global_disable)) | |
1029 | return; | |
1030 | ||
1031 | check_unmap(&ref); | |
1032 | } | |
1033 | EXPORT_SYMBOL(debug_dma_free_coherent); | |
1034 | ||
b9d2317e JR |
1035 | void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, |
1036 | size_t size, int direction) | |
1037 | { | |
1038 | if (unlikely(global_disable)) | |
1039 | return; | |
1040 | ||
1041 | check_sync(dev, dma_handle, size, 0, direction, true); | |
1042 | } | |
1043 | EXPORT_SYMBOL(debug_dma_sync_single_for_cpu); | |
1044 | ||
1045 | void debug_dma_sync_single_for_device(struct device *dev, | |
1046 | dma_addr_t dma_handle, size_t size, | |
1047 | int direction) | |
1048 | { | |
1049 | if (unlikely(global_disable)) | |
1050 | return; | |
1051 | ||
1052 | check_sync(dev, dma_handle, size, 0, direction, false); | |
1053 | } | |
1054 | EXPORT_SYMBOL(debug_dma_sync_single_for_device); | |
1055 | ||
948408ba JR |
1056 | void debug_dma_sync_single_range_for_cpu(struct device *dev, |
1057 | dma_addr_t dma_handle, | |
1058 | unsigned long offset, size_t size, | |
1059 | int direction) | |
1060 | { | |
1061 | if (unlikely(global_disable)) | |
1062 | return; | |
1063 | ||
1064 | check_sync(dev, dma_handle, size, offset, direction, true); | |
1065 | } | |
1066 | EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu); | |
1067 | ||
1068 | void debug_dma_sync_single_range_for_device(struct device *dev, | |
1069 | dma_addr_t dma_handle, | |
1070 | unsigned long offset, | |
1071 | size_t size, int direction) | |
1072 | { | |
1073 | if (unlikely(global_disable)) | |
1074 | return; | |
1075 | ||
1076 | check_sync(dev, dma_handle, size, offset, direction, false); | |
1077 | } | |
1078 | EXPORT_SYMBOL(debug_dma_sync_single_range_for_device); | |
1079 | ||
a31fba5d JR |
1080 | void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, |
1081 | int nelems, int direction) | |
1082 | { | |
1083 | struct scatterlist *s; | |
1084 | int i; | |
1085 | ||
1086 | if (unlikely(global_disable)) | |
1087 | return; | |
1088 | ||
1089 | for_each_sg(sg, s, nelems, i) { | |
1090 | check_sync(dev, s->dma_address, s->dma_length, 0, | |
1091 | direction, true); | |
1092 | } | |
1093 | } | |
1094 | EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu); | |
1095 | ||
1096 | void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, | |
1097 | int nelems, int direction) | |
1098 | { | |
1099 | struct scatterlist *s; | |
1100 | int i; | |
1101 | ||
1102 | if (unlikely(global_disable)) | |
1103 | return; | |
1104 | ||
1105 | for_each_sg(sg, s, nelems, i) { | |
1106 | check_sync(dev, s->dma_address, s->dma_length, 0, | |
1107 | direction, false); | |
1108 | } | |
1109 | } | |
1110 | EXPORT_SYMBOL(debug_dma_sync_sg_for_device); | |
1111 |