1DMA_BUF_BEGIN_CPU_AC(9)  Device drivers infrastructure DMA_BUF_BEGIN_CPU_AC(9)
2
3
4

NAME

6       dma_buf_begin_cpu_access - Must be called before accessing a dma_buf
7       from the cpu in the kernel context. Calls begin_cpu_access to allow
8       exporter-specific preparations. Coherency is only guaranteed in the
9       specified range for the specified access direction.
10

SYNOPSIS

12       int dma_buf_begin_cpu_access(struct dma_buf * dmabuf,
13                                    enum dma_data_direction direction);
14

ARGUMENTS

16       dmabuf
17           [in] buffer to prepare cpu access for.
18
19       direction
20           [in] length of range for cpu access.
21

DESCRIPTION

23       After the cpu access is complete the caller should call
24       dma_buf_end_cpu_access. Only when cpu access is braketed by both calls
25       is it guaranteed to be coherent with other DMA access.
26
27       Can return negative error values, returns 0 on success.
28

30Kernel Hackers Manual 3.10         June 2019           DMA_BUF_BEGIN_CPU_AC(9)
Impressum