Name
dma_buf_begin_cpu_access —
Must be called before accessing a dma_buf from the cpu in the kernel context. Calls begin_cpu_access to allow exporter-specific preparations. Coherency is only guaranteed in the specified range for the specified access direction.
Synopsis
int dma_buf_begin_cpu_access ( | struct dma_buf * dmabuf, |
| enum dma_data_direction direction) ; |
Arguments
dmabuf
[in] buffer to prepare cpu access for.
direction
[in] length of range for cpu access.
Description
After the cpu access is complete the caller should call
dma_buf_end_cpu_access
. Only when cpu access is braketed by both calls is
it guaranteed to be coherent with other DMA access.
Can return negative error values, returns 0 on success.