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Code Issues Releases Wiki Activity

swiotlb: factor out copy to/from device 

Impact: generalize IO bounce memcpys

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jeremy Fitzhardinge 2008-12-16 12:17:32 -08:00 committed by Ingo Molnar
parent b81ea27b23
commit 1b548f667c
1 changed files with 13 additions and 4 deletions
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17
lib/swiotlb.c
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@ -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 @@ found:
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;