From a5008b59cd9d8de12ab623cb5052bb4735330e5c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 16 Jul 2019 22:00:54 +0200 Subject: dma-direct: only limit the mapping size if swiotlb could be used Don't just check for a swiotlb buffer, but also if buffering might be required for this particular device. Fixes: 133d624b1cee ("dma: Introduce dma_max_mapping_size()") Reported-by: Benjamin Herrenschmidt Signed-off-by: Christoph Hellwig Tested-by: Benjamin Herrenschmidt --- kernel/dma/direct.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index d7cec866d16b5..e269b6f9b4441 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -399,11 +399,9 @@ int dma_direct_supported(struct device *dev, u64 mask) size_t dma_direct_max_mapping_size(struct device *dev) { - size_t size = SIZE_MAX; - /* If SWIOTLB is active, use its maximum mapping size */ - if (is_swiotlb_active()) - size = swiotlb_max_mapping_size(dev); - - return size; + if (is_swiotlb_active() && + (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE)) + return swiotlb_max_mapping_size(dev); + return SIZE_MAX; } -- cgit v1.2.3