Interface:
int dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
- size_t start, size_t len,
enum dma_data_direction direction)
This allows the exporter to ensure that the memory is actually available for
cpu access - the exporter might need to allocate or swap-in and pin the
backing storage. The exporter also needs to ensure that cpu access is
- coherent for the given range and access direction. The range and access
- direction can be used by the exporter to optimize the cache flushing, i.e.
- access outside of the range or with a different direction (read instead of
- write) might return stale or even bogus data (e.g. when the exporter needs to
- copy the data to temporary storage).
+ coherent for the access direction. The direction can be used by the exporter
+ to optimize the cache flushing, i.e. access with a different direction (read
+ instead of write) might return stale or even bogus data (e.g. when the
+ exporter needs to copy the data to temporary storage).
This step might fail, e.g. in oom conditions.
3. Finish access
- When the importer is done accessing the range specified in begin_cpu_access,
- it needs to announce this to the exporter (to facilitate cache flushing and
- unpinning of any pinned resources). The result of any dma_buf kmap calls
- after end_cpu_access is undefined.
+ When the importer is done accessing the CPU, it needs to announce this to
+ the exporter (to facilitate cache flushing and unpinning of any pinned
+ resources). The result of any dma_buf kmap calls after end_cpu_access is
+ undefined.
Interface:
void dma_buf_end_cpu_access(struct dma_buf *dma_buf,
- size_t start, size_t len,
enum dma_data_direction dir);
* preparations. Coherency is only guaranteed in the specified range for the
* specified access direction.
* @dmabuf: [in] buffer to prepare cpu access for.
- * @start: [in] start of range for cpu access.
- * @len: [in] length of range for cpu access.
* @direction: [in] length of range for cpu access.
*
* Can return negative error values, returns 0 on success.
*/
-int dma_buf_begin_cpu_access(struct dma_buf *dmabuf, size_t start, size_t len,
+int dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
enum dma_data_direction direction)
{
int ret = 0;
return -EINVAL;
if (dmabuf->ops->begin_cpu_access)
- ret = dmabuf->ops->begin_cpu_access(dmabuf, start,
- len, direction);
+ ret = dmabuf->ops->begin_cpu_access(dmabuf, direction);
return ret;
}
* actions. Coherency is only guaranteed in the specified range for the
* specified access direction.
* @dmabuf: [in] buffer to complete cpu access for.
- * @start: [in] start of range for cpu access.
- * @len: [in] length of range for cpu access.
* @direction: [in] length of range for cpu access.
*
* This call must always succeed.
*/
-void dma_buf_end_cpu_access(struct dma_buf *dmabuf, size_t start, size_t len,
+void dma_buf_end_cpu_access(struct dma_buf *dmabuf,
enum dma_data_direction direction)
{
WARN_ON(!dmabuf);
if (dmabuf->ops->end_cpu_access)
- dmabuf->ops->end_cpu_access(dmabuf, start, len, direction);
+ dmabuf->ops->end_cpu_access(dmabuf, direction);
}
EXPORT_SYMBOL_GPL(dma_buf_end_cpu_access);
KBASE_DEBUG_ASSERT(dma_buf != NULL);
- ret = dma_buf_begin_cpu_access(dma_buf, 0,
- buf_data->nr_extres_pages*PAGE_SIZE,
- DMA_FROM_DEVICE);
+ ret = dma_buf_begin_cpu_access(dma_buf, DMA_FROM_DEVICE);
if (ret)
goto out_unlock;
if (target_page_nr >= buf_data->nr_pages)
break;
}
- dma_buf_end_cpu_access(dma_buf, 0,
- buf_data->nr_extres_pages*PAGE_SIZE,
- DMA_FROM_DEVICE);
+ dma_buf_end_cpu_access(dma_buf, DMA_FROM_DEVICE);
break;
}
#endif
return -EINVAL;
}
-static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size_t length, enum dma_data_direction direction)
+static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
{
struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
struct drm_device *dev = obj->base.dev;
static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,
- size_t start, size_t len, enum dma_data_direction dir)
+ enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
}
static void omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,
- size_t start, size_t len, enum dma_data_direction dir)
+ enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
omap_gem_put_pages(obj);
if (ufb->obj->base.import_attach) {
ret = dma_buf_begin_cpu_access(ufb->obj->base.import_attach->dmabuf,
- 0, ufb->obj->base.size,
DMA_FROM_DEVICE);
if (ret)
goto unlock;
if (ufb->obj->base.import_attach) {
dma_buf_end_cpu_access(ufb->obj->base.import_attach->dmabuf,
- 0, ufb->obj->base.size,
DMA_FROM_DEVICE);
}
{
}
-static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, size_t start,
- size_t len,
+static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
enum dma_data_direction direction)
{
struct ion_buffer *buffer = dmabuf->priv;
return PTR_ERR_OR_ZERO(vaddr);
}
-static void ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf, size_t start,
- size_t len,
+static void ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
enum dma_data_direction direction)
{
struct ion_buffer *buffer = dmabuf->priv;
if (offset > dma_buf->size || size > dma_buf->size - offset)
return -EINVAL;
- ret = dma_buf_begin_cpu_access(dma_buf, offset, size, dir);
+ ret = dma_buf_begin_cpu_access(dma_buf, dir);
if (ret)
return ret;
copy_offset = 0;
}
err:
- dma_buf_end_cpu_access(dma_buf, offset, size, dir);
+ dma_buf_end_cpu_access(dma_buf, dir);
return ret;
}
* @release: release this buffer; to be called after the last dma_buf_put.
* @begin_cpu_access: [optional] called before cpu access to invalidate cpu
* caches and allocate backing storage (if not yet done)
- * respectively pin the objet into memory.
+ * respectively pin the object into memory.
* @end_cpu_access: [optional] called after cpu access to flush caches.
* @kmap_atomic: maps a page from the buffer into kernel address
* space, users may not block until the subsequent unmap call.
/* after final dma_buf_put() */
void (*release)(struct dma_buf *);
- int (*begin_cpu_access)(struct dma_buf *, size_t, size_t,
- enum dma_data_direction);
- void (*end_cpu_access)(struct dma_buf *, size_t, size_t,
- enum dma_data_direction);
+ int (*begin_cpu_access)(struct dma_buf *, enum dma_data_direction);
+ void (*end_cpu_access)(struct dma_buf *, enum dma_data_direction);
void *(*kmap_atomic)(struct dma_buf *, unsigned long);
void (*kunmap_atomic)(struct dma_buf *, unsigned long, void *);
void *(*kmap)(struct dma_buf *, unsigned long);
enum dma_data_direction);
void dma_buf_unmap_attachment(struct dma_buf_attachment *, struct sg_table *,
enum dma_data_direction);
-int dma_buf_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size_t len,
+int dma_buf_begin_cpu_access(struct dma_buf *dma_buf,
enum dma_data_direction dir);
-void dma_buf_end_cpu_access(struct dma_buf *dma_buf, size_t start, size_t len,
+void dma_buf_end_cpu_access(struct dma_buf *dma_buf,
enum dma_data_direction dir);
void *dma_buf_kmap_atomic(struct dma_buf *, unsigned long);
void dma_buf_kunmap_atomic(struct dma_buf *, unsigned long, void *);