dma_buf_begin_cpu_access9

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.

Usage

int dma_buf_begin_cpu_access(struct dma_buf * dmabuf, size_t start, size_t len, enum dma_data_direction direction);

Arguments

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.

Overview

Can return negative error values, returns 0 on success.