diff options
Diffstat (limited to 'kernel/dma/direct.c')
| -rw-r--r-- | kernel/dma/direct.c | 37 |
1 files changed, 13 insertions, 24 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 9596ae1aa0da..ed3056eb20b8 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -220,13 +220,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, return dma_direct_alloc_no_mapping(dev, size, dma_handle, gfp); if (!dev_is_dma_coherent(dev)) { - /* - * Fallback to the arch handler if it exists. This should - * eventually go away. - */ - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && - !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - !IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_ALLOC) && !is_swiotlb_for_alloc(dev)) return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); @@ -240,27 +234,24 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_handle); /* - * Otherwise remap if the architecture is asking for it. But - * given that remapping memory is a blocking operation we'll - * instead have to dip into the atomic pools. + * Otherwise we require the architecture to either be able to + * mark arbitrary parts of the kernel direct mapping uncached, + * or remapped it uncached. */ + set_uncached = IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED); remap = IS_ENABLED(CONFIG_DMA_DIRECT_REMAP); - if (remap) { - if (dma_direct_use_pool(dev, gfp)) - return dma_direct_alloc_from_pool(dev, size, - dma_handle, gfp); - } else { - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED)) - return NULL; - set_uncached = true; + if (!set_uncached && !remap) { + pr_warn_once("coherent DMA allocations not supported on this platform.\n"); + return NULL; } } /* - * Decrypting memory may block, so allocate the memory from the atomic - * pools if we can't block. + * Remapping or decrypting memory may block, allocate the memory from + * the atomic pools instead if we aren't allowed block. */ - if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp)) + if ((remap || force_dma_unencrypted(dev)) && + dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp); /* we always manually zero the memory once we are done */ @@ -330,9 +321,7 @@ void dma_direct_free(struct device *dev, size_t size, return; } - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && - !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - !IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_ALLOC) && !dev_is_dma_coherent(dev) && !is_swiotlb_for_alloc(dev)) { arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); |