dma_unmap_page(NULL, sg->dma_address, sg->length, DMA_FROM_DEVICE);
/* Swap the contents of the buffer */
buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;
dma_unmap_page(NULL, sg->dma_address, sg->length, DMA_FROM_DEVICE);
/* Swap the contents of the buffer */
buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;