dma_pool_create — Creates a pool of consistent memory blocks, for dma.
struct dma_pool * dma_pool_create ( | const char * | name, |
struct device * | dev, | |
size_t | size, | |
size_t | align, | |
size_t | boundary) ; |
name
name of pool, for diagnostics
dev
device that will be doing the DMA
size
size of the blocks in this pool.
align
alignment requirement for blocks; must be a power of two
boundary
returned blocks won't cross this power of two boundary
Returns a dma allocation pool with the requested characteristics, or
null if one can't be created. Given one of these pools, dma_pool_alloc
may be used to allocate memory. Such memory will all have “consistent”
DMA mappings, accessible by the device and its driver without using
cache flushing primitives. The actual size of blocks allocated may be
larger than requested because of alignment.
If boundary
is nonzero, objects returned from dma_pool_alloc
won't
cross that size boundary. This is useful for devices which have
addressing restrictions on individual DMA transfers, such as not crossing
boundaries of 4KBytes.