Module attrs

DMA mapping attributes.

Constants

DMA_ATTR_ALLOC_SINGLE_PAGES

This is a hint to the DMA-mapping subsystem that it’s probably not worth the time to try to allocate memory to in a way that gives better TLB efficiency.

DMA_ATTR_FORCE_CONTIGUOUS

Forces contiguous allocation of the buffer in physical memory.

DMA_ATTR_NO_KERNEL_MAPPING

Lets the platform to avoid creating a kernel virtual mapping for the allocated buffer.

DMA_ATTR_NO_WARN

This tells the DMA-mapping subsystem to suppress allocation failure reports (similarly to __GFP_NOWARN).

DMA_ATTR_PRIVILEGED

Used to indicate that the buffer is fully accessible at an elevated privilege level (and ideally inaccessible or at least read-only at lesser-privileged levels).

DMA_ATTR_SKIP_CPU_SYNC

Allows platform code to skip synchronization of the CPU cache for the given buffer assuming that it has been already transferred to ‘device’ domain.

DMA_ATTR_WEAK_ORDERING

Specifies that reads and writes to the mapping may be weakly ordered, that is that reads and writes may pass each other.

DMA_ATTR_WRITE_COMBINE

Specifies that writes to the mapping may be buffered to improve performance.