2 * Copyright (C) 2008 Advanced Micro Devices, Inc.
4 * Author: Joerg Roedel <joerg.roedel@amd.com>
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.
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.
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
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/uaccess.h>
27 #include <linux/device.h>
28 #include <linux/types.h>
29 #include <linux/sched.h>
30 #include <linux/ctype.h>
31 #include <linux/list.h>
32 #include <linux/slab.h>
34 #include <asm/sections.h>
36 #define HASH_SIZE 1024ULL
37 #define HASH_FN_SHIFT 13
38 #define HASH_FN_MASK (HASH_SIZE - 1)
47 #define DMA_DEBUG_STACKTRACE_ENTRIES 5
49 struct dma_debug_entry {
50 struct list_head list;
59 #ifdef CONFIG_STACKTRACE
60 struct stack_trace stacktrace;
61 unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
66 struct list_head list;
68 } ____cacheline_aligned_in_smp;
70 /* Hash list to save the allocated dma addresses */
71 static struct hash_bucket dma_entry_hash[HASH_SIZE];
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);
77 /* Global disable flag - will be set in case of an error */
78 static bool global_disable __read_mostly;
80 /* Global error count */
81 static u32 error_count;
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;
88 static u32 num_free_entries;
89 static u32 min_free_entries;
90 static u32 nr_total_entries;
92 /* number of preallocated entries requested by kernel cmdline */
93 static u32 req_entries;
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;
103 static struct dentry *filter_dent __read_mostly;
105 /* per-driver filter related state */
107 #define NAME_MAX_LEN 64
109 static char current_driver_name[NAME_MAX_LEN] __read_mostly;
110 static struct device_driver *current_driver __read_mostly;
112 static DEFINE_RWLOCK(driver_name_lock);
114 static const char *type2name[4] = { "single", "page",
115 "scather-gather", "coherent" };
117 static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
118 "DMA_FROM_DEVICE", "DMA_NONE" };
120 /* little merge helper - remove it after the merge window */
121 #ifndef BUS_NOTIFY_UNBOUND_DRIVER
122 #define BUS_NOTIFY_UNBOUND_DRIVER 0x0005
126 * The access to some variables in this macro is racy. We can't use atomic_t
127 * here because all these variables are exported to debugfs. Some of them even
128 * writeable. This is also the reason why a lock won't help much. But anyway,
129 * the races are no big deal. Here is why:
131 * error_count: the addition is racy, but the worst thing that can happen is
132 * that we don't count some errors
133 * show_num_errors: the subtraction is racy. Also no big deal because in
134 * worst case this will result in one warning more in the
135 * system log than the user configured. This variable is
136 * writeable via debugfs.
138 static inline void dump_entry_trace(struct dma_debug_entry *entry)
140 #ifdef CONFIG_STACKTRACE
142 pr_warning("Mapped at:\n");
143 print_stack_trace(&entry->stacktrace, 0);
148 static bool driver_filter(struct device *dev)
150 struct device_driver *drv;
154 /* driver filter off */
155 if (likely(!current_driver_name[0]))
158 /* driver filter on and initialized */
159 if (current_driver && dev->driver == current_driver)
162 if (current_driver || !current_driver_name[0])
165 /* driver filter on but not yet initialized */
166 drv = get_driver(dev->driver);
170 /* lock to protect against change of current_driver_name */
171 read_lock_irqsave(&driver_name_lock, flags);
175 strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) {
176 current_driver = drv;
180 read_unlock_irqrestore(&driver_name_lock, flags);
186 #define err_printk(dev, entry, format, arg...) do { \
188 if (driver_filter(dev) && \
189 (show_all_errors || show_num_errors > 0)) { \
190 WARN(1, "%s %s: " format, \
191 dev_driver_string(dev), \
192 dev_name(dev) , ## arg); \
193 dump_entry_trace(entry); \
195 if (!show_all_errors && show_num_errors > 0) \
196 show_num_errors -= 1; \
200 * Hash related functions
202 * Every DMA-API request is saved into a struct dma_debug_entry. To
203 * have quick access to these structs they are stored into a hash.
205 static int hash_fn(struct dma_debug_entry *entry)
208 * Hash function is based on the dma address.
209 * We use bits 20-27 here as the index into the hash
211 return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
215 * Request exclusive access to a hash bucket for a given dma_debug_entry.
217 static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
218 unsigned long *flags)
220 int idx = hash_fn(entry);
221 unsigned long __flags;
223 spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
225 return &dma_entry_hash[idx];
229 * Give up exclusive access to the hash bucket
231 static void put_hash_bucket(struct hash_bucket *bucket,
232 unsigned long *flags)
234 unsigned long __flags = *flags;
236 spin_unlock_irqrestore(&bucket->lock, __flags);
240 * Search a given entry in the hash bucket list
242 static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket,
243 struct dma_debug_entry *ref)
245 struct dma_debug_entry *entry, *ret = NULL;
246 int matches = 0, match_lvl, last_lvl = 0;
248 list_for_each_entry(entry, &bucket->list, list) {
249 if ((entry->dev_addr != ref->dev_addr) ||
250 (entry->dev != ref->dev))
254 * Some drivers map the same physical address multiple
255 * times. Without a hardware IOMMU this results in the
256 * same device addresses being put into the dma-debug
257 * hash multiple times too. This can result in false
258 * positives being reported. Therfore we implement a
259 * best-fit algorithm here which returns the entry from
260 * the hash which fits best to the reference value
261 * instead of the first-fit.
265 entry->size == ref->size ? ++match_lvl : 0;
266 entry->type == ref->type ? ++match_lvl : 0;
267 entry->direction == ref->direction ? ++match_lvl : 0;
268 entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0;
270 if (match_lvl == 4) {
271 /* perfect-fit - return the result */
273 } else if (match_lvl > last_lvl) {
275 * We found an entry that fits better then the
278 last_lvl = match_lvl;
284 * If we have multiple matches but no perfect-fit, just return
287 ret = (matches == 1) ? ret : NULL;
293 * Add an entry to a hash bucket
295 static void hash_bucket_add(struct hash_bucket *bucket,
296 struct dma_debug_entry *entry)
298 list_add_tail(&entry->list, &bucket->list);
302 * Remove entry from a hash bucket list
304 static void hash_bucket_del(struct dma_debug_entry *entry)
306 list_del(&entry->list);
310 * Dump mapping entries for debugging purposes
312 void debug_dma_dump_mappings(struct device *dev)
316 for (idx = 0; idx < HASH_SIZE; idx++) {
317 struct hash_bucket *bucket = &dma_entry_hash[idx];
318 struct dma_debug_entry *entry;
321 spin_lock_irqsave(&bucket->lock, flags);
323 list_for_each_entry(entry, &bucket->list, list) {
324 if (!dev || dev == entry->dev) {
326 "%s idx %d P=%Lx D=%Lx L=%Lx %s\n",
327 type2name[entry->type], idx,
328 (unsigned long long)entry->paddr,
329 entry->dev_addr, entry->size,
330 dir2name[entry->direction]);
334 spin_unlock_irqrestore(&bucket->lock, flags);
337 EXPORT_SYMBOL(debug_dma_dump_mappings);
340 * Wrapper function for adding an entry to the hash.
341 * This function takes care of locking itself.
343 static void add_dma_entry(struct dma_debug_entry *entry)
345 struct hash_bucket *bucket;
348 bucket = get_hash_bucket(entry, &flags);
349 hash_bucket_add(bucket, entry);
350 put_hash_bucket(bucket, &flags);
353 static struct dma_debug_entry *__dma_entry_alloc(void)
355 struct dma_debug_entry *entry;
357 entry = list_entry(free_entries.next, struct dma_debug_entry, list);
358 list_del(&entry->list);
359 memset(entry, 0, sizeof(*entry));
361 num_free_entries -= 1;
362 if (num_free_entries < min_free_entries)
363 min_free_entries = num_free_entries;
368 /* struct dma_entry allocator
370 * The next two functions implement the allocator for
371 * struct dma_debug_entries.
373 static struct dma_debug_entry *dma_entry_alloc(void)
375 struct dma_debug_entry *entry = NULL;
378 spin_lock_irqsave(&free_entries_lock, flags);
380 if (list_empty(&free_entries)) {
381 pr_err("DMA-API: debugging out of memory - disabling\n");
382 global_disable = true;
386 entry = __dma_entry_alloc();
388 #ifdef CONFIG_STACKTRACE
389 entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
390 entry->stacktrace.entries = entry->st_entries;
391 entry->stacktrace.skip = 2;
392 save_stack_trace(&entry->stacktrace);
396 spin_unlock_irqrestore(&free_entries_lock, flags);
401 static void dma_entry_free(struct dma_debug_entry *entry)
406 * add to beginning of the list - this way the entries are
407 * more likely cache hot when they are reallocated.
409 spin_lock_irqsave(&free_entries_lock, flags);
410 list_add(&entry->list, &free_entries);
411 num_free_entries += 1;
412 spin_unlock_irqrestore(&free_entries_lock, flags);
415 int dma_debug_resize_entries(u32 num_entries)
417 int i, delta, ret = 0;
419 struct dma_debug_entry *entry;
422 spin_lock_irqsave(&free_entries_lock, flags);
424 if (nr_total_entries < num_entries) {
425 delta = num_entries - nr_total_entries;
427 spin_unlock_irqrestore(&free_entries_lock, flags);
429 for (i = 0; i < delta; i++) {
430 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
434 list_add_tail(&entry->list, &tmp);
437 spin_lock_irqsave(&free_entries_lock, flags);
439 list_splice(&tmp, &free_entries);
440 nr_total_entries += i;
441 num_free_entries += i;
443 delta = nr_total_entries - num_entries;
445 for (i = 0; i < delta && !list_empty(&free_entries); i++) {
446 entry = __dma_entry_alloc();
450 nr_total_entries -= i;
453 if (nr_total_entries != num_entries)
456 spin_unlock_irqrestore(&free_entries_lock, flags);
460 EXPORT_SYMBOL(dma_debug_resize_entries);
463 * DMA-API debugging init code
465 * The init code does two things:
466 * 1. Initialize core data structures
467 * 2. Preallocate a given number of dma_debug_entry structs
470 static int prealloc_memory(u32 num_entries)
472 struct dma_debug_entry *entry, *next_entry;
475 for (i = 0; i < num_entries; ++i) {
476 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
480 list_add_tail(&entry->list, &free_entries);
483 num_free_entries = num_entries;
484 min_free_entries = num_entries;
486 pr_info("DMA-API: preallocated %d debug entries\n", num_entries);
492 list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
493 list_del(&entry->list);
500 static ssize_t filter_read(struct file *file, char __user *user_buf,
501 size_t count, loff_t *ppos)
503 char buf[NAME_MAX_LEN + 1];
507 if (!current_driver_name[0])
511 * We can't copy to userspace directly because current_driver_name can
512 * only be read under the driver_name_lock with irqs disabled. So
513 * create a temporary copy first.
515 read_lock_irqsave(&driver_name_lock, flags);
516 len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name);
517 read_unlock_irqrestore(&driver_name_lock, flags);
519 return simple_read_from_buffer(user_buf, count, ppos, buf, len);
522 static ssize_t filter_write(struct file *file, const char __user *userbuf,
523 size_t count, loff_t *ppos)
525 char buf[NAME_MAX_LEN];
531 * We can't copy from userspace directly. Access to
532 * current_driver_name is protected with a write_lock with irqs
533 * disabled. Since copy_from_user can fault and may sleep we
534 * need to copy to temporary buffer first
536 len = min(count, (size_t)(NAME_MAX_LEN - 1));
537 if (copy_from_user(buf, userbuf, len))
542 write_lock_irqsave(&driver_name_lock, flags);
545 * Now handle the string we got from userspace very carefully.
547 * - only use the first token we got
548 * - token delimiter is everything looking like a space
549 * character (' ', '\n', '\t' ...)
552 if (!isalnum(buf[0])) {
554 * If the first character userspace gave us is not
555 * alphanumerical then assume the filter should be
558 if (current_driver_name[0])
559 pr_info("DMA-API: switching off dma-debug driver filter\n");
560 current_driver_name[0] = 0;
561 current_driver = NULL;
566 * Now parse out the first token and use it as the name for the
567 * driver to filter for.
569 for (i = 0; i < NAME_MAX_LEN; ++i) {
570 current_driver_name[i] = buf[i];
571 if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0)
574 current_driver_name[i] = 0;
575 current_driver = NULL;
577 pr_info("DMA-API: enable driver filter for driver [%s]\n",
578 current_driver_name);
581 write_unlock_irqrestore(&driver_name_lock, flags);
586 const struct file_operations filter_fops = {
588 .write = filter_write,
591 static int dma_debug_fs_init(void)
593 dma_debug_dent = debugfs_create_dir("dma-api", NULL);
594 if (!dma_debug_dent) {
595 pr_err("DMA-API: can not create debugfs directory\n");
599 global_disable_dent = debugfs_create_bool("disabled", 0444,
601 (u32 *)&global_disable);
602 if (!global_disable_dent)
605 error_count_dent = debugfs_create_u32("error_count", 0444,
606 dma_debug_dent, &error_count);
607 if (!error_count_dent)
610 show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
613 if (!show_all_errors_dent)
616 show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
619 if (!show_num_errors_dent)
622 num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
625 if (!num_free_entries_dent)
628 min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
631 if (!min_free_entries_dent)
634 filter_dent = debugfs_create_file("driver_filter", 0644,
635 dma_debug_dent, NULL, &filter_fops);
642 debugfs_remove_recursive(dma_debug_dent);
647 static int device_dma_allocations(struct device *dev)
649 struct dma_debug_entry *entry;
653 local_irq_save(flags);
655 for (i = 0; i < HASH_SIZE; ++i) {
656 spin_lock(&dma_entry_hash[i].lock);
657 list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
658 if (entry->dev == dev)
661 spin_unlock(&dma_entry_hash[i].lock);
664 local_irq_restore(flags);
669 static int dma_debug_device_change(struct notifier_block *nb,
670 unsigned long action, void *data)
672 struct device *dev = data;
677 case BUS_NOTIFY_UNBOUND_DRIVER:
678 count = device_dma_allocations(dev);
681 err_printk(dev, NULL, "DMA-API: device driver has pending "
682 "DMA allocations while released from device "
683 "[count=%d]\n", count);
692 void dma_debug_add_bus(struct bus_type *bus)
694 struct notifier_block *nb;
696 nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
698 pr_err("dma_debug_add_bus: out of memory\n");
702 nb->notifier_call = dma_debug_device_change;
704 bus_register_notifier(bus, nb);
708 * Let the architectures decide how many entries should be preallocated.
710 void dma_debug_init(u32 num_entries)
717 for (i = 0; i < HASH_SIZE; ++i) {
718 INIT_LIST_HEAD(&dma_entry_hash[i].list);
719 dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
722 if (dma_debug_fs_init() != 0) {
723 pr_err("DMA-API: error creating debugfs entries - disabling\n");
724 global_disable = true;
730 num_entries = req_entries;
732 if (prealloc_memory(num_entries) != 0) {
733 pr_err("DMA-API: debugging out of memory error - disabled\n");
734 global_disable = true;
739 nr_total_entries = num_free_entries;
741 pr_info("DMA-API: debugging enabled by kernel config\n");
744 static __init int dma_debug_cmdline(char *str)
749 if (strncmp(str, "off", 3) == 0) {
750 pr_info("DMA-API: debugging disabled on kernel command line\n");
751 global_disable = true;
757 static __init int dma_debug_entries_cmdline(char *str)
764 res = get_option(&str, &req_entries);
772 __setup("dma_debug=", dma_debug_cmdline);
773 __setup("dma_debug_entries=", dma_debug_entries_cmdline);
775 static void check_unmap(struct dma_debug_entry *ref)
777 struct dma_debug_entry *entry;
778 struct hash_bucket *bucket;
781 if (dma_mapping_error(ref->dev, ref->dev_addr)) {
782 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
783 "to free an invalid DMA memory address\n");
787 bucket = get_hash_bucket(ref, &flags);
788 entry = hash_bucket_find(bucket, ref);
791 err_printk(ref->dev, NULL, "DMA-API: device driver tries "
792 "to free DMA memory it has not allocated "
793 "[device address=0x%016llx] [size=%llu bytes]\n",
794 ref->dev_addr, ref->size);
798 if (ref->size != entry->size) {
799 err_printk(ref->dev, entry, "DMA-API: device driver frees "
800 "DMA memory with different size "
801 "[device address=0x%016llx] [map size=%llu bytes] "
802 "[unmap size=%llu bytes]\n",
803 ref->dev_addr, entry->size, ref->size);
806 if (ref->type != entry->type) {
807 err_printk(ref->dev, entry, "DMA-API: device driver frees "
808 "DMA memory with wrong function "
809 "[device address=0x%016llx] [size=%llu bytes] "
810 "[mapped as %s] [unmapped as %s]\n",
811 ref->dev_addr, ref->size,
812 type2name[entry->type], type2name[ref->type]);
813 } else if ((entry->type == dma_debug_coherent) &&
814 (ref->paddr != entry->paddr)) {
815 err_printk(ref->dev, entry, "DMA-API: device driver frees "
816 "DMA memory with different CPU address "
817 "[device address=0x%016llx] [size=%llu bytes] "
818 "[cpu alloc address=%p] [cpu free address=%p]",
819 ref->dev_addr, ref->size,
820 (void *)entry->paddr, (void *)ref->paddr);
823 if (ref->sg_call_ents && ref->type == dma_debug_sg &&
824 ref->sg_call_ents != entry->sg_call_ents) {
825 err_printk(ref->dev, entry, "DMA-API: device driver frees "
826 "DMA sg list with different entry count "
827 "[map count=%d] [unmap count=%d]\n",
828 entry->sg_call_ents, ref->sg_call_ents);
832 * This may be no bug in reality - but most implementations of the
833 * DMA API don't handle this properly, so check for it here
835 if (ref->direction != entry->direction) {
836 err_printk(ref->dev, entry, "DMA-API: device driver frees "
837 "DMA memory with different direction "
838 "[device address=0x%016llx] [size=%llu bytes] "
839 "[mapped with %s] [unmapped with %s]\n",
840 ref->dev_addr, ref->size,
841 dir2name[entry->direction],
842 dir2name[ref->direction]);
845 hash_bucket_del(entry);
846 dma_entry_free(entry);
849 put_hash_bucket(bucket, &flags);
852 static void check_for_stack(struct device *dev, void *addr)
854 if (object_is_on_stack(addr))
855 err_printk(dev, NULL, "DMA-API: device driver maps memory from"
856 "stack [addr=%p]\n", addr);
859 static inline bool overlap(void *addr, u64 size, void *start, void *end)
861 void *addr2 = (char *)addr + size;
863 return ((addr >= start && addr < end) ||
864 (addr2 >= start && addr2 < end) ||
865 ((addr < start) && (addr2 >= end)));
868 static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
870 if (overlap(addr, size, _text, _etext) ||
871 overlap(addr, size, __start_rodata, __end_rodata))
872 err_printk(dev, NULL, "DMA-API: device driver maps "
873 "memory from kernel text or rodata "
874 "[addr=%p] [size=%llu]\n", addr, size);
877 static void check_sync(struct device *dev, dma_addr_t addr,
878 u64 size, u64 offset, int direction, bool to_cpu)
880 struct dma_debug_entry ref = {
884 .direction = direction,
886 struct dma_debug_entry *entry;
887 struct hash_bucket *bucket;
890 bucket = get_hash_bucket(&ref, &flags);
892 entry = hash_bucket_find(bucket, &ref);
895 err_printk(dev, NULL, "DMA-API: device driver tries "
896 "to sync DMA memory it has not allocated "
897 "[device address=0x%016llx] [size=%llu bytes]\n",
898 (unsigned long long)addr, size);
902 if ((offset + size) > entry->size) {
903 err_printk(dev, entry, "DMA-API: device driver syncs"
904 " DMA memory outside allocated range "
905 "[device address=0x%016llx] "
906 "[allocation size=%llu bytes] [sync offset=%llu] "
907 "[sync size=%llu]\n", entry->dev_addr, entry->size,
911 if (direction != entry->direction) {
912 err_printk(dev, entry, "DMA-API: device driver syncs "
913 "DMA memory with different direction "
914 "[device address=0x%016llx] [size=%llu bytes] "
915 "[mapped with %s] [synced with %s]\n",
916 (unsigned long long)addr, entry->size,
917 dir2name[entry->direction],
918 dir2name[direction]);
921 if (entry->direction == DMA_BIDIRECTIONAL)
924 if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
925 !(direction == DMA_TO_DEVICE))
926 err_printk(dev, entry, "DMA-API: device driver syncs "
927 "device read-only DMA memory for cpu "
928 "[device address=0x%016llx] [size=%llu bytes] "
929 "[mapped with %s] [synced with %s]\n",
930 (unsigned long long)addr, entry->size,
931 dir2name[entry->direction],
932 dir2name[direction]);
934 if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
935 !(direction == DMA_FROM_DEVICE))
936 err_printk(dev, entry, "DMA-API: device driver syncs "
937 "device write-only DMA memory to device "
938 "[device address=0x%016llx] [size=%llu bytes] "
939 "[mapped with %s] [synced with %s]\n",
940 (unsigned long long)addr, entry->size,
941 dir2name[entry->direction],
942 dir2name[direction]);
945 put_hash_bucket(bucket, &flags);
949 void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
950 size_t size, int direction, dma_addr_t dma_addr,
953 struct dma_debug_entry *entry;
955 if (unlikely(global_disable))
958 if (unlikely(dma_mapping_error(dev, dma_addr)))
961 entry = dma_entry_alloc();
966 entry->type = dma_debug_page;
967 entry->paddr = page_to_phys(page) + offset;
968 entry->dev_addr = dma_addr;
970 entry->direction = direction;
973 entry->type = dma_debug_single;
975 if (!PageHighMem(page)) {
976 void *addr = ((char *)page_address(page)) + offset;
977 check_for_stack(dev, addr);
978 check_for_illegal_area(dev, addr, size);
981 add_dma_entry(entry);
983 EXPORT_SYMBOL(debug_dma_map_page);
985 void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
986 size_t size, int direction, bool map_single)
988 struct dma_debug_entry ref = {
989 .type = dma_debug_page,
993 .direction = direction,
996 if (unlikely(global_disable))
1000 ref.type = dma_debug_single;
1004 EXPORT_SYMBOL(debug_dma_unmap_page);
1006 void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
1007 int nents, int mapped_ents, int direction)
1009 struct dma_debug_entry *entry;
1010 struct scatterlist *s;
1013 if (unlikely(global_disable))
1016 for_each_sg(sg, s, mapped_ents, i) {
1017 entry = dma_entry_alloc();
1021 entry->type = dma_debug_sg;
1023 entry->paddr = sg_phys(s);
1024 entry->size = sg_dma_len(s);
1025 entry->dev_addr = sg_dma_address(s);
1026 entry->direction = direction;
1027 entry->sg_call_ents = nents;
1028 entry->sg_mapped_ents = mapped_ents;
1030 if (!PageHighMem(sg_page(s))) {
1031 check_for_stack(dev, sg_virt(s));
1032 check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s));
1035 add_dma_entry(entry);
1038 EXPORT_SYMBOL(debug_dma_map_sg);
1040 static int get_nr_mapped_entries(struct device *dev, struct scatterlist *s)
1042 struct dma_debug_entry *entry, ref;
1043 struct hash_bucket *bucket;
1044 unsigned long flags;
1048 ref.dev_addr = sg_dma_address(s);
1049 ref.size = sg_dma_len(s),
1051 bucket = get_hash_bucket(&ref, &flags);
1052 entry = hash_bucket_find(bucket, &ref);
1056 mapped_ents = entry->sg_mapped_ents;
1057 put_hash_bucket(bucket, &flags);
1062 void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
1063 int nelems, int dir)
1065 struct scatterlist *s;
1066 int mapped_ents = 0, i;
1068 if (unlikely(global_disable))
1071 for_each_sg(sglist, s, nelems, i) {
1073 struct dma_debug_entry ref = {
1074 .type = dma_debug_sg,
1076 .paddr = sg_phys(s),
1077 .dev_addr = sg_dma_address(s),
1078 .size = sg_dma_len(s),
1080 .sg_call_ents = nelems,
1083 if (mapped_ents && i >= mapped_ents)
1087 mapped_ents = get_nr_mapped_entries(dev, s);
1092 EXPORT_SYMBOL(debug_dma_unmap_sg);
1094 void debug_dma_alloc_coherent(struct device *dev, size_t size,
1095 dma_addr_t dma_addr, void *virt)
1097 struct dma_debug_entry *entry;
1099 if (unlikely(global_disable))
1102 if (unlikely(virt == NULL))
1105 entry = dma_entry_alloc();
1109 entry->type = dma_debug_coherent;
1111 entry->paddr = virt_to_phys(virt);
1113 entry->dev_addr = dma_addr;
1114 entry->direction = DMA_BIDIRECTIONAL;
1116 add_dma_entry(entry);
1118 EXPORT_SYMBOL(debug_dma_alloc_coherent);
1120 void debug_dma_free_coherent(struct device *dev, size_t size,
1121 void *virt, dma_addr_t addr)
1123 struct dma_debug_entry ref = {
1124 .type = dma_debug_coherent,
1126 .paddr = virt_to_phys(virt),
1129 .direction = DMA_BIDIRECTIONAL,
1132 if (unlikely(global_disable))
1137 EXPORT_SYMBOL(debug_dma_free_coherent);
1139 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
1140 size_t size, int direction)
1142 if (unlikely(global_disable))
1145 check_sync(dev, dma_handle, size, 0, direction, true);
1147 EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
1149 void debug_dma_sync_single_for_device(struct device *dev,
1150 dma_addr_t dma_handle, size_t size,
1153 if (unlikely(global_disable))
1156 check_sync(dev, dma_handle, size, 0, direction, false);
1158 EXPORT_SYMBOL(debug_dma_sync_single_for_device);
1160 void debug_dma_sync_single_range_for_cpu(struct device *dev,
1161 dma_addr_t dma_handle,
1162 unsigned long offset, size_t size,
1165 if (unlikely(global_disable))
1168 check_sync(dev, dma_handle, size, offset, direction, true);
1170 EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
1172 void debug_dma_sync_single_range_for_device(struct device *dev,
1173 dma_addr_t dma_handle,
1174 unsigned long offset,
1175 size_t size, int direction)
1177 if (unlikely(global_disable))
1180 check_sync(dev, dma_handle, size, offset, direction, false);
1182 EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
1184 void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
1185 int nelems, int direction)
1187 struct scatterlist *s;
1188 int mapped_ents = 0, i;
1190 if (unlikely(global_disable))
1193 for_each_sg(sg, s, nelems, i) {
1195 mapped_ents = get_nr_mapped_entries(dev, s);
1197 if (i >= mapped_ents)
1200 check_sync(dev, sg_dma_address(s), sg_dma_len(s), 0,
1204 EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
1206 void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
1207 int nelems, int direction)
1209 struct scatterlist *s;
1210 int mapped_ents = 0, i;
1212 if (unlikely(global_disable))
1215 for_each_sg(sg, s, nelems, i) {
1217 mapped_ents = get_nr_mapped_entries(dev, s);
1219 if (i >= mapped_ents)
1222 check_sync(dev, sg_dma_address(s), sg_dma_len(s), 0,
1226 EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
1228 static int __init dma_debug_driver_setup(char *str)
1232 for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
1233 current_driver_name[i] = *str;
1238 if (current_driver_name[0])
1239 pr_info("DMA-API: enable driver filter for driver [%s]\n",
1240 current_driver_name);
1245 __setup("dma_debug_driver=", dma_debug_driver_setup);