Commit 1b548f66 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Ingo Molnar
Browse files

swiotlb: factor out copy to/from device 



Impact: generalize IO bounce memcpys

Signed-off-by: default avatarIan Campbell <ian.campbell@citrix.com>
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b81ea27b

lib/swiotlb.c

+13 −4
Original line number Diff line number Diff line
@@ -312,6 +312,15 @@ static int is_swiotlb_buffer(char *addr) 
	return addr >= io_tlb_start && addr < io_tlb_end;

}



static void

__sync_single(char *buffer, char *dma_addr, size_t size, int dir)

{

	if (dir == DMA_TO_DEVICE)

		memcpy(dma_addr, buffer, size);

	else

		memcpy(buffer, dma_addr, size);

}



/*

 * Allocates bounce buffer and returns its kernel virtual address.

 */
@@ -413,7 +422,7 @@ map_single(struct device *hwdev, char *buffer, size_t size, int dir) 
	for (i = 0; i < nslots; i++)

		io_tlb_orig_addr[index+i] = buffer + (i << IO_TLB_SHIFT);

	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)

		memcpy(dma_addr, buffer, size);

		__sync_single(buffer, dma_addr, size, DMA_TO_DEVICE);



	return dma_addr;

}
@@ -437,7 +446,7 @@ unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir) 
		 * bounce... copy the data back into the original buffer * and

		 * delete the bounce buffer.

		 */

		memcpy(buffer, dma_addr, size);

		__sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE);



	/*

	 * Return the buffer to the free list by setting the corresponding
@@ -477,13 +486,13 @@ sync_single(struct device *hwdev, char *dma_addr, size_t size, 
	switch (target) {

	case SYNC_FOR_CPU:

		if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))

			memcpy(buffer, dma_addr, size);

			__sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE);

		else

			BUG_ON(dir != DMA_TO_DEVICE);

		break;

	case SYNC_FOR_DEVICE:

		if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))

			memcpy(dma_addr, buffer, size);

			__sync_single(buffer, dma_addr, size, DMA_TO_DEVICE);

		else

			BUG_ON(dir != DMA_FROM_DEVICE);

		break;