From df336d1c7b6fd510fa6d3a028f999e7586c7026e Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Sat, 21 Jul 2007 04:37:24 -0700 Subject: [PATCH] Fix swiotlb_sync_single_range() If the swiotlb maps a multi-slab region, swiotlb_sync_single_range() can be invoked to sync a sub-region which does not include the first slab. Unfortunately io_tlb_orig_addr[] is only initialised for the first slab, and hence the call to sync_single() will read a garbage orig_addr in this case. This patch fixes the issue by initialising all mapped slabs in io_tlb_orig_addr[]. It also correctly adjusts the buffer pointer in sync_single() to handle the case that the given dma_addr is not aligned on a slab boundary. Signed-off-by: Keir Fraser Cc: "Luck, Tony" Acked-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/swiotlb.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 10c13ad0d82d..a7381d55663a 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -357,7 +357,8 @@ map_single(struct device *hwdev, char *buffer, size_t size, int dir) * This is needed when we sync the memory. Then we sync the buffer if * needed. */ - io_tlb_orig_addr[index] = buffer; + 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); @@ -418,6 +419,8 @@ sync_single(struct device *hwdev, char *dma_addr, size_t size, int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT; char *buffer = io_tlb_orig_addr[index]; + buffer += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1)); + switch (target) { case SYNC_FOR_CPU: if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)) -- 2.20.1