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Diffstat (limited to 'arch/arm/common/dmabounce.c')
-rw-r--r--arch/arm/common/dmabounce.c193
1 files changed, 83 insertions, 110 deletions
diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c
index e5681636626f..595ecd290ebf 100644
--- a/arch/arm/common/dmabounce.c
+++ b/arch/arm/common/dmabounce.c
@@ -79,6 +79,8 @@ struct dmabounce_device_info {
struct dmabounce_pool large;
rwlock_t lock;
+
+ int (*needs_bounce)(struct device *, dma_addr_t, size_t);
};
#ifdef STATS
@@ -210,114 +212,91 @@ static struct safe_buffer *find_safe_buffer_dev(struct device *dev,
if (!dev || !dev->archdata.dmabounce)
return NULL;
if (dma_mapping_error(dev, dma_addr)) {
- if (dev)
- dev_err(dev, "Trying to %s invalid mapping\n", where);
- else
- pr_err("unknown device: Trying to %s invalid mapping\n", where);
+ dev_err(dev, "Trying to %s invalid mapping\n", where);
return NULL;
}
return find_safe_buffer(dev->archdata.dmabounce, dma_addr);
}
-static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size,
- enum dma_data_direction dir)
+static int needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
{
- struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
- dma_addr_t dma_addr;
- int needs_bounce = 0;
-
- if (device_info)
- DO_STATS ( device_info->map_op_count++ );
-
- dma_addr = virt_to_dma(dev, ptr);
+ if (!dev || !dev->archdata.dmabounce)
+ return 0;
if (dev->dma_mask) {
- unsigned long mask = *dev->dma_mask;
- unsigned long limit;
+ unsigned long limit, mask = *dev->dma_mask;
limit = (mask + 1) & ~mask;
if (limit && size > limit) {
dev_err(dev, "DMA mapping too big (requested %#x "
"mask %#Lx)\n", size, *dev->dma_mask);
- return ~0;
+ return -E2BIG;
}
- /*
- * Figure out if we need to bounce from the DMA mask.
- */
- needs_bounce = (dma_addr | (dma_addr + size - 1)) & ~mask;
+ /* Figure out if we need to bounce from the DMA mask. */
+ if ((dma_addr | (dma_addr + size - 1)) & ~mask)
+ return 1;
}
- if (device_info && (needs_bounce || dma_needs_bounce(dev, dma_addr, size))) {
- struct safe_buffer *buf;
+ return !!dev->archdata.dmabounce->needs_bounce(dev, dma_addr, size);
+}
- buf = alloc_safe_buffer(device_info, ptr, size, dir);
- if (buf == 0) {
- dev_err(dev, "%s: unable to map unsafe buffer %p!\n",
- __func__, ptr);
- return 0;
- }
+static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size,
+ enum dma_data_direction dir)
+{
+ struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
+ struct safe_buffer *buf;
- dev_dbg(dev,
- "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
- __func__, buf->ptr, virt_to_dma(dev, buf->ptr),
- buf->safe, buf->safe_dma_addr);
+ if (device_info)
+ DO_STATS ( device_info->map_op_count++ );
- if ((dir == DMA_TO_DEVICE) ||
- (dir == DMA_BIDIRECTIONAL)) {
- dev_dbg(dev, "%s: copy unsafe %p to safe %p, size %d\n",
- __func__, ptr, buf->safe, size);
- memcpy(buf->safe, ptr, size);
- }
- ptr = buf->safe;
+ buf = alloc_safe_buffer(device_info, ptr, size, dir);
+ if (buf == NULL) {
+ dev_err(dev, "%s: unable to map unsafe buffer %p!\n",
+ __func__, ptr);
+ return ~0;
+ }
- dma_addr = buf->safe_dma_addr;
- } else {
- /*
- * We don't need to sync the DMA buffer since
- * it was allocated via the coherent allocators.
- */
- __dma_single_cpu_to_dev(ptr, size, dir);
+ dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
+ __func__, buf->ptr, virt_to_dma(dev, buf->ptr),
+ buf->safe, buf->safe_dma_addr);
+
+ if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) {
+ dev_dbg(dev, "%s: copy unsafe %p to safe %p, size %d\n",
+ __func__, ptr, buf->safe, size);
+ memcpy(buf->safe, ptr, size);
}
- return dma_addr;
+ return buf->safe_dma_addr;
}
-static inline void unmap_single(struct device *dev, dma_addr_t dma_addr,
+static inline void unmap_single(struct device *dev, struct safe_buffer *buf,
size_t size, enum dma_data_direction dir)
{
- struct safe_buffer *buf = find_safe_buffer_dev(dev, dma_addr, "unmap");
-
- if (buf) {
- BUG_ON(buf->size != size);
- BUG_ON(buf->direction != dir);
+ BUG_ON(buf->size != size);
+ BUG_ON(buf->direction != dir);
- dev_dbg(dev,
- "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
- __func__, buf->ptr, virt_to_dma(dev, buf->ptr),
- buf->safe, buf->safe_dma_addr);
+ dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
+ __func__, buf->ptr, virt_to_dma(dev, buf->ptr),
+ buf->safe, buf->safe_dma_addr);
- DO_STATS(dev->archdata.dmabounce->bounce_count++);
+ DO_STATS(dev->archdata.dmabounce->bounce_count++);
- if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {
- void *ptr = buf->ptr;
+ if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {
+ void *ptr = buf->ptr;
- dev_dbg(dev,
- "%s: copy back safe %p to unsafe %p size %d\n",
- __func__, buf->safe, ptr, size);
- memcpy(ptr, buf->safe, size);
+ dev_dbg(dev, "%s: copy back safe %p to unsafe %p size %d\n",
+ __func__, buf->safe, ptr, size);
+ memcpy(ptr, buf->safe, size);
- /*
- * Since we may have written to a page cache page,
- * we need to ensure that the data will be coherent
- * with user mappings.
- */
- __cpuc_flush_dcache_area(ptr, size);
- }
- free_safe_buffer(dev->archdata.dmabounce, buf);
- } else {
- __dma_single_dev_to_cpu(dma_to_virt(dev, dma_addr), size, dir);
+ /*
+ * Since we may have written to a page cache page,
+ * we need to ensure that the data will be coherent
+ * with user mappings.
+ */
+ __cpuc_flush_dcache_area(ptr, size);
}
+ free_safe_buffer(dev->archdata.dmabounce, buf);
}
/* ************************************************** */
@@ -328,45 +307,28 @@ static inline void unmap_single(struct device *dev, dma_addr_t dma_addr,
* substitute the safe buffer for the unsafe one.
* (basically move the buffer from an unsafe area to a safe one)
*/
-dma_addr_t __dma_map_single(struct device *dev, void *ptr, size_t size,
- enum dma_data_direction dir)
-{
- dev_dbg(dev, "%s(ptr=%p,size=%d,dir=%x)\n",
- __func__, ptr, size, dir);
-
- BUG_ON(!valid_dma_direction(dir));
-
- return map_single(dev, ptr, size, dir);
-}
-EXPORT_SYMBOL(__dma_map_single);
-
-/*
- * see if a mapped address was really a "safe" buffer and if so, copy
- * the data from the safe buffer back to the unsafe buffer and free up
- * the safe buffer. (basically return things back to the way they
- * should be)
- */
-void __dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
- enum dma_data_direction dir)
-{
- dev_dbg(dev, "%s(ptr=%p,size=%d,dir=%x)\n",
- __func__, (void *) dma_addr, size, dir);
-
- unmap_single(dev, dma_addr, size, dir);
-}
-EXPORT_SYMBOL(__dma_unmap_single);
-
dma_addr_t __dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir)
{
+ dma_addr_t dma_addr;
+ int ret;
+
dev_dbg(dev, "%s(page=%p,off=%#lx,size=%zx,dir=%x)\n",
__func__, page, offset, size, dir);
- BUG_ON(!valid_dma_direction(dir));
+ dma_addr = pfn_to_dma(dev, page_to_pfn(page)) + offset;
+
+ ret = needs_bounce(dev, dma_addr, size);
+ if (ret < 0)
+ return ~0;
+
+ if (ret == 0) {
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+ return dma_addr;
+ }
if (PageHighMem(page)) {
- dev_err(dev, "DMA buffer bouncing of HIGHMEM pages "
- "is not supported\n");
+ dev_err(dev, "DMA buffer bouncing of HIGHMEM pages is not supported\n");
return ~0;
}
@@ -383,10 +345,19 @@ EXPORT_SYMBOL(__dma_map_page);
void __dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir)
{
- dev_dbg(dev, "%s(ptr=%p,size=%d,dir=%x)\n",
- __func__, (void *) dma_addr, size, dir);
+ struct safe_buffer *buf;
+
+ dev_dbg(dev, "%s(dma=%#x,size=%d,dir=%x)\n",
+ __func__, dma_addr, size, dir);
+
+ buf = find_safe_buffer_dev(dev, dma_addr, __func__);
+ if (!buf) {
+ __dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, dma_addr)),
+ dma_addr & ~PAGE_MASK, size, dir);
+ return;
+ }
- unmap_single(dev, dma_addr, size, dir);
+ unmap_single(dev, buf, size, dir);
}
EXPORT_SYMBOL(__dma_unmap_page);
@@ -461,7 +432,8 @@ static int dmabounce_init_pool(struct dmabounce_pool *pool, struct device *dev,
}
int dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
- unsigned long large_buffer_size)
+ unsigned long large_buffer_size,
+ int (*needs_bounce_fn)(struct device *, dma_addr_t, size_t))
{
struct dmabounce_device_info *device_info;
int ret;
@@ -497,6 +469,7 @@ int dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
device_info->dev = dev;
INIT_LIST_HEAD(&device_info->safe_buffers);
rwlock_init(&device_info->lock);
+ device_info->needs_bounce = needs_bounce_fn;
#ifdef STATS
device_info->total_allocs = 0;