[PATCH 08 of 14] swiotlb: factor out copy to/from device

Jeremy Fitzhardinge
2008-12-16T20:21:52Z

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
---
lib/swiotlb.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -312,6 +312,15 @@
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 @@
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 @@
* 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 @@
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;