Two dma-direct / swiotlb regressions fixes

- 0 is a valid physical address on some arm boards, we can't use
    0 as the error value
  - don't try to cache flush the error return value (no matter what it is)
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Merge tag 'dma-mapping-4.20-3' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:
 "Two dma-direct / swiotlb regressions fixes:

   - zero is a valid physical address on some arm boards, we can't use
     it as the error value

   - don't try to cache flush the error return value (no matter what it
     is)"

* tag 'dma-mapping-4.20-3' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: Skip cache maintenance on map error
  dma-direct: Make DIRECT_MAPPING_ERROR viable for SWIOTLB
This commit is contained in:
Linus Torvalds 2018-11-25 09:24:40 -08:00
commit d6d460b893
2 changed files with 3 additions and 2 deletions

View File

@ -5,7 +5,7 @@
#include <linux/dma-mapping.h>
#include <linux/mem_encrypt.h>
#define DIRECT_MAPPING_ERROR 0
#define DIRECT_MAPPING_ERROR (~(dma_addr_t)0)
#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
#include <asm/dma-direct.h>

View File

@ -679,7 +679,8 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
}
if (!dev_is_dma_coherent(dev) &&
(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0 &&
dev_addr != DIRECT_MAPPING_ERROR)
arch_sync_dma_for_device(dev, phys, size, dir);
return dev_addr;