Deallocates resources previously allocated on a d_unmap_page call.
#include <sys/dma.h>
void d_unmap_page (*handle, *busaddr)
struct d_handle *handle
uint *busaddr
int d_unmap_page(*handle,
*busaddr)
struct d_handle *handle;
unsigned long long *busaddr;
Item | Description |
---|---|
handle | Indicates the unique handle returned by the d_map_init kernel service. |
busaddr | Points to the busaddr field. |
The d_unmap_page kernel service is a bus-specific utility routine determined by the d_map_init kernel service that deallocates resources previously allocated on a d_map_page call for a DMA master device.
The d_unmap_page service must be called after I/O completion involving the area mapped by the prior d_map_page call. Some device drivers might choose to leave pages mapped for a long-term mapping of certain memory buffers. In this case, the driver must call d_unmap_page when it no longer needs the long-term mapping.