diff options
| -rw-r--r-- | include/linux/dma-mapping.h | 7 | ||||
| -rw-r--r-- | kernel/dma/debug.c | 3 |
2 files changed, 9 insertions, 1 deletions
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 29ad2ce700f0..29973baa0581 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -80,6 +80,13 @@ #define DMA_ATTR_MMIO (1UL << 10) /* + * DMA_ATTR_CPU_CACHE_CLEAN: Indicates the CPU will not dirty any cacheline + * overlapping this buffer while it is mapped for DMA. All mappings sharing + * a cacheline must have this attribute for this to be considered safe. + */ +#define DMA_ATTR_CPU_CACHE_CLEAN (1UL << 11) + +/* * A dma_addr_t can hold any valid DMA or bus address for the platform. It can * be given to a device to use as a DMA source or target. It is specific to a * given device and there may be a translation between the CPU physical address diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 138ede653de4..7e66d863d573 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -595,7 +595,8 @@ static void add_dma_entry(struct dma_debug_entry *entry, unsigned long attrs) if (rc == -ENOMEM) { pr_err_once("cacheline tracking ENOMEM, dma-debug disabled\n"); global_disable = true; - } else if (rc == -EEXIST && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && + } else if (rc == -EEXIST && + !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_CPU_CACHE_CLEAN)) && !(IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && is_swiotlb_active(entry->dev))) { err_printk(entry->dev, entry, |