Merge branch 'topic/memdup_user' into for-linus
[pandora-kernel.git] / lib / dma-debug.c
index d0cb47a..d3da7ed 100644 (file)
@@ -17,7 +17,9 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
+#include <linux/scatterlist.h>
 #include <linux/dma-mapping.h>
+#include <linux/stacktrace.h>
 #include <linux/dma-debug.h>
 #include <linux/spinlock.h>
 #include <linux/debugfs.h>
@@ -27,6 +29,8 @@
 #include <linux/list.h>
 #include <linux/slab.h>
 
+#include <asm/sections.h>
+
 #define HASH_SIZE       1024ULL
 #define HASH_FN_SHIFT   13
 #define HASH_FN_MASK    (HASH_SIZE - 1)
@@ -38,6 +42,8 @@ enum {
        dma_debug_coherent,
 };
 
+#define DMA_DEBUG_STACKTRACE_ENTRIES 5
+
 struct dma_debug_entry {
        struct list_head list;
        struct device    *dev;
@@ -48,6 +54,10 @@ struct dma_debug_entry {
        int              direction;
        int              sg_call_ents;
        int              sg_mapped_ents;
+#ifdef CONFIG_STACKTRACE
+       struct           stack_trace stacktrace;
+       unsigned long    st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
+#endif
 };
 
 struct hash_bucket {
@@ -107,12 +117,23 @@ static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
  *                    system log than the user configured. This variable is
  *                    writeable via debugfs.
  */
-#define err_printk(dev, format, arg...) do {                   \
+static inline void dump_entry_trace(struct dma_debug_entry *entry)
+{
+#ifdef CONFIG_STACKTRACE
+       if (entry) {
+               printk(KERN_WARNING "Mapped at:\n");
+               print_stack_trace(&entry->stacktrace, 0);
+       }
+#endif
+}
+
+#define err_printk(dev, entry, format, arg...) do {            \
                error_count += 1;                               \
                if (show_all_errors || show_num_errors > 0) {   \
                        WARN(1, "%s %s: " format,               \
                             dev_driver_string(dev),            \
                             dev_name(dev) , ## arg);           \
+                       dump_entry_trace(entry);                \
                }                                               \
                if (!show_all_errors && show_num_errors > 0)    \
                        show_num_errors -= 1;                   \
@@ -192,6 +213,36 @@ static void hash_bucket_del(struct dma_debug_entry *entry)
        list_del(&entry->list);
 }
 
+/*
+ * Dump mapping entries for debugging purposes
+ */
+void debug_dma_dump_mappings(struct device *dev)
+{
+       int idx;
+
+       for (idx = 0; idx < HASH_SIZE; idx++) {
+               struct hash_bucket *bucket = &dma_entry_hash[idx];
+               struct dma_debug_entry *entry;
+               unsigned long flags;
+
+               spin_lock_irqsave(&bucket->lock, flags);
+
+               list_for_each_entry(entry, &bucket->list, list) {
+                       if (!dev || dev == entry->dev) {
+                               dev_info(entry->dev,
+                                        "%s idx %d P=%Lx D=%Lx L=%Lx %s\n",
+                                        type2name[entry->type], idx,
+                                        (unsigned long long)entry->paddr,
+                                        entry->dev_addr, entry->size,
+                                        dir2name[entry->direction]);
+                       }
+               }
+
+               spin_unlock_irqrestore(&bucket->lock, flags);
+       }
+}
+EXPORT_SYMBOL(debug_dma_dump_mappings);
+
 /*
  * Wrapper function for adding an entry to the hash.
  * This function takes care of locking itself.
@@ -229,6 +280,12 @@ static struct dma_debug_entry *dma_entry_alloc(void)
        list_del(&entry->list);
        memset(entry, 0, sizeof(*entry));
 
+#ifdef CONFIG_STACKTRACE
+       entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
+       entry->stacktrace.entries = entry->st_entries;
+       entry->stacktrace.skip = 2;
+       save_stack_trace(&entry->stacktrace);
+#endif
        num_free_entries -= 1;
        if (num_free_entries < min_free_entries)
                min_free_entries = num_free_entries;
@@ -343,6 +400,61 @@ out_err:
        return -ENOMEM;
 }
 
+static int device_dma_allocations(struct device *dev)
+{
+       struct dma_debug_entry *entry;
+       unsigned long flags;
+       int count = 0, i;
+
+       for (i = 0; i < HASH_SIZE; ++i) {
+               spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
+               list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
+                       if (entry->dev == dev)
+                               count += 1;
+               }
+               spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
+       }
+
+       return count;
+}
+
+static int dma_debug_device_change(struct notifier_block *nb,
+                                   unsigned long action, void *data)
+{
+       struct device *dev = data;
+       int count;
+
+
+       switch (action) {
+       case BUS_NOTIFY_UNBIND_DRIVER:
+               count = device_dma_allocations(dev);
+               if (count == 0)
+                       break;
+               err_printk(dev, NULL, "DMA-API: device driver has pending "
+                               "DMA allocations while released from device "
+                               "[count=%d]\n", count);
+               break;
+       default:
+               break;
+       }
+
+       return 0;
+}
+
+void dma_debug_add_bus(struct bus_type *bus)
+{
+       struct notifier_block *nb;
+
+       nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
+       if (nb == NULL) {
+               printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
+               return;
+       }
+
+       nb->notifier_call = dma_debug_device_change;
+
+       bus_register_notifier(bus, nb);
+}
 
 /*
  * Let the architectures decide how many entries should be preallocated.
@@ -419,14 +531,17 @@ static void check_unmap(struct dma_debug_entry *ref)
        struct hash_bucket *bucket;
        unsigned long flags;
 
-       if (dma_mapping_error(ref->dev, ref->dev_addr))
+       if (dma_mapping_error(ref->dev, ref->dev_addr)) {
+               err_printk(ref->dev, NULL, "DMA-API: device driver tries "
+                          "to free an invalid DMA memory address\n");
                return;
+       }
 
        bucket = get_hash_bucket(ref, &flags);
        entry = hash_bucket_find(bucket, ref);
 
        if (!entry) {
-               err_printk(ref->dev, "DMA-API: device driver tries "
+               err_printk(ref->dev, NULL, "DMA-API: device driver tries "
                           "to free DMA memory it has not allocated "
                           "[device address=0x%016llx] [size=%llu bytes]\n",
                           ref->dev_addr, ref->size);
@@ -434,7 +549,7 @@ static void check_unmap(struct dma_debug_entry *ref)
        }
 
        if (ref->size != entry->size) {
-               err_printk(ref->dev, "DMA-API: device driver frees "
+               err_printk(ref->dev, entry, "DMA-API: device driver frees "
                           "DMA memory with different size "
                           "[device address=0x%016llx] [map size=%llu bytes] "
                           "[unmap size=%llu bytes]\n",
@@ -442,7 +557,7 @@ static void check_unmap(struct dma_debug_entry *ref)
        }
 
        if (ref->type != entry->type) {
-               err_printk(ref->dev, "DMA-API: device driver frees "
+               err_printk(ref->dev, entry, "DMA-API: device driver frees "
                           "DMA memory with wrong function "
                           "[device address=0x%016llx] [size=%llu bytes] "
                           "[mapped as %s] [unmapped as %s]\n",
@@ -450,7 +565,7 @@ static void check_unmap(struct dma_debug_entry *ref)
                           type2name[entry->type], type2name[ref->type]);
        } else if ((entry->type == dma_debug_coherent) &&
                   (ref->paddr != entry->paddr)) {
-               err_printk(ref->dev, "DMA-API: device driver frees "
+               err_printk(ref->dev, entry, "DMA-API: device driver frees "
                           "DMA memory with different CPU address "
                           "[device address=0x%016llx] [size=%llu bytes] "
                           "[cpu alloc address=%p] [cpu free address=%p]",
@@ -460,7 +575,7 @@ static void check_unmap(struct dma_debug_entry *ref)
 
        if (ref->sg_call_ents && ref->type == dma_debug_sg &&
            ref->sg_call_ents != entry->sg_call_ents) {
-               err_printk(ref->dev, "DMA-API: device driver frees "
+               err_printk(ref->dev, entry, "DMA-API: device driver frees "
                           "DMA sg list with different entry count "
                           "[map count=%d] [unmap count=%d]\n",
                           entry->sg_call_ents, ref->sg_call_ents);
@@ -471,7 +586,7 @@ static void check_unmap(struct dma_debug_entry *ref)
         * DMA API don't handle this properly, so check for it here
         */
        if (ref->direction != entry->direction) {
-               err_printk(ref->dev, "DMA-API: device driver frees "
+               err_printk(ref->dev, entry, "DMA-API: device driver frees "
                           "DMA memory with different direction "
                           "[device address=0x%016llx] [size=%llu bytes] "
                           "[mapped with %s] [unmapped with %s]\n",
@@ -490,8 +605,26 @@ out:
 static void check_for_stack(struct device *dev, void *addr)
 {
        if (object_is_on_stack(addr))
-               err_printk(dev, "DMA-API: device driver maps memory from stack"
-                               " [addr=%p]\n", addr);
+               err_printk(dev, NULL, "DMA-API: device driver maps memory from"
+                               "stack [addr=%p]\n", addr);
+}
+
+static inline bool overlap(void *addr, u64 size, void *start, void *end)
+{
+       void *addr2 = (char *)addr + size;
+
+       return ((addr >= start && addr < end) ||
+               (addr2 >= start && addr2 < end) ||
+               ((addr < start) && (addr2 >= end)));
+}
+
+static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
+{
+       if (overlap(addr, size, _text, _etext) ||
+           overlap(addr, size, __start_rodata, __end_rodata))
+               err_printk(dev, NULL, "DMA-API: device driver maps "
+                               "memory from kernel text or rodata "
+                               "[addr=%p] [size=%llu]\n", addr, size);
 }
 
 static void check_sync(struct device *dev, dma_addr_t addr,
@@ -512,15 +645,15 @@ static void check_sync(struct device *dev, dma_addr_t addr,
        entry = hash_bucket_find(bucket, &ref);
 
        if (!entry) {
-               err_printk(dev, "DMA-API: device driver tries "
+               err_printk(dev, NULL, "DMA-API: device driver tries "
                                "to sync DMA memory it has not allocated "
                                "[device address=0x%016llx] [size=%llu bytes]\n",
-                               addr, size);
+                               (unsigned long long)addr, size);
                goto out;
        }
 
        if ((offset + size) > entry->size) {
-               err_printk(dev, "DMA-API: device driver syncs"
+               err_printk(dev, entry, "DMA-API: device driver syncs"
                                " DMA memory outside allocated range "
                                "[device address=0x%016llx] "
                                "[allocation size=%llu bytes] [sync offset=%llu] "
@@ -529,11 +662,11 @@ static void check_sync(struct device *dev, dma_addr_t addr,
        }
 
        if (direction != entry->direction) {
-               err_printk(dev, "DMA-API: device driver syncs "
+               err_printk(dev, entry, "DMA-API: device driver syncs "
                                "DMA memory with different direction "
                                "[device address=0x%016llx] [size=%llu bytes] "
                                "[mapped with %s] [synced with %s]\n",
-                               addr, entry->size,
+                               (unsigned long long)addr, entry->size,
                                dir2name[entry->direction],
                                dir2name[direction]);
        }
@@ -543,21 +676,21 @@ static void check_sync(struct device *dev, dma_addr_t addr,
 
        if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
                      !(direction == DMA_TO_DEVICE))
-               err_printk(dev, "DMA-API: device driver syncs "
+               err_printk(dev, entry, "DMA-API: device driver syncs "
                                "device read-only DMA memory for cpu "
                                "[device address=0x%016llx] [size=%llu bytes] "
                                "[mapped with %s] [synced with %s]\n",
-                               addr, entry->size,
+                               (unsigned long long)addr, entry->size,
                                dir2name[entry->direction],
                                dir2name[direction]);
 
        if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
                       !(direction == DMA_FROM_DEVICE))
-               err_printk(dev, "DMA-API: device driver syncs "
+               err_printk(dev, entry, "DMA-API: device driver syncs "
                                "device write-only DMA memory to device "
                                "[device address=0x%016llx] [size=%llu bytes] "
                                "[mapped with %s] [synced with %s]\n",
-                               addr, entry->size,
+                               (unsigned long long)addr, entry->size,
                                dir2name[entry->direction],
                                dir2name[direction]);
 
@@ -566,3 +699,257 @@ out:
 
 }
 
+void debug_dma_map_page(struct device *dev, struct page *page, size_t offset,
+                       size_t size, int direction, dma_addr_t dma_addr,
+                       bool map_single)
+{
+       struct dma_debug_entry *entry;
+
+       if (unlikely(global_disable))
+               return;
+
+       if (unlikely(dma_mapping_error(dev, dma_addr)))
+               return;
+
+       entry = dma_entry_alloc();
+       if (!entry)
+               return;
+
+       entry->dev       = dev;
+       entry->type      = dma_debug_page;
+       entry->paddr     = page_to_phys(page) + offset;
+       entry->dev_addr  = dma_addr;
+       entry->size      = size;
+       entry->direction = direction;
+
+       if (map_single)
+               entry->type = dma_debug_single;
+
+       if (!PageHighMem(page)) {
+               void *addr = ((char *)page_address(page)) + offset;
+               check_for_stack(dev, addr);
+               check_for_illegal_area(dev, addr, size);
+       }
+
+       add_dma_entry(entry);
+}
+EXPORT_SYMBOL(debug_dma_map_page);
+
+void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
+                         size_t size, int direction, bool map_single)
+{
+       struct dma_debug_entry ref = {
+               .type           = dma_debug_page,
+               .dev            = dev,
+               .dev_addr       = addr,
+               .size           = size,
+               .direction      = direction,
+       };
+
+       if (unlikely(global_disable))
+               return;
+
+       if (map_single)
+               ref.type = dma_debug_single;
+
+       check_unmap(&ref);
+}
+EXPORT_SYMBOL(debug_dma_unmap_page);
+
+void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
+                     int nents, int mapped_ents, int direction)
+{
+       struct dma_debug_entry *entry;
+       struct scatterlist *s;
+       int i;
+
+       if (unlikely(global_disable))
+               return;
+
+       for_each_sg(sg, s, mapped_ents, i) {
+               entry = dma_entry_alloc();
+               if (!entry)
+                       return;
+
+               entry->type           = dma_debug_sg;
+               entry->dev            = dev;
+               entry->paddr          = sg_phys(s);
+               entry->size           = s->length;
+               entry->dev_addr       = s->dma_address;
+               entry->direction      = direction;
+               entry->sg_call_ents   = nents;
+               entry->sg_mapped_ents = mapped_ents;
+
+               if (!PageHighMem(sg_page(s))) {
+                       check_for_stack(dev, sg_virt(s));
+                       check_for_illegal_area(dev, sg_virt(s), s->length);
+               }
+
+               add_dma_entry(entry);
+       }
+}
+EXPORT_SYMBOL(debug_dma_map_sg);
+
+void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
+                       int nelems, int dir)
+{
+       struct dma_debug_entry *entry;
+       struct scatterlist *s;
+       int mapped_ents = 0, i;
+       unsigned long flags;
+
+       if (unlikely(global_disable))
+               return;
+
+       for_each_sg(sglist, s, nelems, i) {
+
+               struct dma_debug_entry ref = {
+                       .type           = dma_debug_sg,
+                       .dev            = dev,
+                       .paddr          = sg_phys(s),
+                       .dev_addr       = s->dma_address,
+                       .size           = s->length,
+                       .direction      = dir,
+                       .sg_call_ents   = 0,
+               };
+
+               if (mapped_ents && i >= mapped_ents)
+                       break;
+
+               if (mapped_ents == 0) {
+                       struct hash_bucket *bucket;
+                       ref.sg_call_ents = nelems;
+                       bucket = get_hash_bucket(&ref, &flags);
+                       entry = hash_bucket_find(bucket, &ref);
+                       if (entry)
+                               mapped_ents = entry->sg_mapped_ents;
+                       put_hash_bucket(bucket, &flags);
+               }
+
+               check_unmap(&ref);
+       }
+}
+EXPORT_SYMBOL(debug_dma_unmap_sg);
+
+void debug_dma_alloc_coherent(struct device *dev, size_t size,
+                             dma_addr_t dma_addr, void *virt)
+{
+       struct dma_debug_entry *entry;
+
+       if (unlikely(global_disable))
+               return;
+
+       if (unlikely(virt == NULL))
+               return;
+
+       entry = dma_entry_alloc();
+       if (!entry)
+               return;
+
+       entry->type      = dma_debug_coherent;
+       entry->dev       = dev;
+       entry->paddr     = virt_to_phys(virt);
+       entry->size      = size;
+       entry->dev_addr  = dma_addr;
+       entry->direction = DMA_BIDIRECTIONAL;
+
+       add_dma_entry(entry);
+}
+EXPORT_SYMBOL(debug_dma_alloc_coherent);
+
+void debug_dma_free_coherent(struct device *dev, size_t size,
+                        void *virt, dma_addr_t addr)
+{
+       struct dma_debug_entry ref = {
+               .type           = dma_debug_coherent,
+               .dev            = dev,
+               .paddr          = virt_to_phys(virt),
+               .dev_addr       = addr,
+               .size           = size,
+               .direction      = DMA_BIDIRECTIONAL,
+       };
+
+       if (unlikely(global_disable))
+               return;
+
+       check_unmap(&ref);
+}
+EXPORT_SYMBOL(debug_dma_free_coherent);
+
+void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
+                                  size_t size, int direction)
+{
+       if (unlikely(global_disable))
+               return;
+
+       check_sync(dev, dma_handle, size, 0, direction, true);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
+
+void debug_dma_sync_single_for_device(struct device *dev,
+                                     dma_addr_t dma_handle, size_t size,
+                                     int direction)
+{
+       if (unlikely(global_disable))
+               return;
+
+       check_sync(dev, dma_handle, size, 0, direction, false);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_for_device);
+
+void debug_dma_sync_single_range_for_cpu(struct device *dev,
+                                        dma_addr_t dma_handle,
+                                        unsigned long offset, size_t size,
+                                        int direction)
+{
+       if (unlikely(global_disable))
+               return;
+
+       check_sync(dev, dma_handle, size, offset, direction, true);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
+
+void debug_dma_sync_single_range_for_device(struct device *dev,
+                                           dma_addr_t dma_handle,
+                                           unsigned long offset,
+                                           size_t size, int direction)
+{
+       if (unlikely(global_disable))
+               return;
+
+       check_sync(dev, dma_handle, size, offset, direction, false);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
+
+void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+                              int nelems, int direction)
+{
+       struct scatterlist *s;
+       int i;
+
+       if (unlikely(global_disable))
+               return;
+
+       for_each_sg(sg, s, nelems, i) {
+               check_sync(dev, s->dma_address, s->dma_length, 0,
+                               direction, true);
+       }
+}
+EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
+
+void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+                                 int nelems, int direction)
+{
+       struct scatterlist *s;
+       int i;
+
+       if (unlikely(global_disable))
+               return;
+
+       for_each_sg(sg, s, nelems, i) {
+               check_sync(dev, s->dma_address, s->dma_length, 0,
+                               direction, false);
+       }
+}
+EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
+