Introduce a FLAG for the restricted memory which means the memory is protected by TEE or hypervisor, then it's inaccessiable for kernel.
Currently we don't use sg_dma_unmark_restricted, thus this interface has not been added.
Signed-off-by: Yong Wu yong.wu@mediatek.com --- include/linux/scatterlist.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h index 77df3d7b18a6..a6ad9018eca0 100644 --- a/include/linux/scatterlist.h +++ b/include/linux/scatterlist.h @@ -282,6 +282,7 @@ static inline void sg_unmark_end(struct scatterlist *sg)
#define SG_DMA_BUS_ADDRESS (1 << 0) #define SG_DMA_SWIOTLB (1 << 1) +#define SG_DMA_RESTRICTED (2 << 1)
/** * sg_dma_is_bus_address - Return whether a given segment was marked @@ -352,6 +353,31 @@ static inline void sg_dma_mark_swiotlb(struct scatterlist *sg) sg->dma_flags |= SG_DMA_SWIOTLB; }
+/** + * sg_dma_mark_restricted - Mark the scatterlist for restricted buffer. + * @sg: SG entry + * + * Description: + * Marks a a scatterlist for the restricted buffer that may be inaccessiable + * in kernel if it is protected. + */ +static inline void sg_dma_mark_restricted(struct scatterlist *sg) +{ + sg->dma_flags |= SG_DMA_RESTRICTED; +} + +/** + * sg_dma_is_restricted - Return whether the scatterlist was marked as restricted + * buffer. + * @sg: SG entry + * + * Description: + * Returns true if the scatterlist was marked as restricted buffer. + */ +static inline bool sg_dma_is_restricted(struct scatterlist *sg) +{ + return sg->dma_flags & SG_DMA_RESTRICTED; +} #else
static inline bool sg_dma_is_bus_address(struct scatterlist *sg) @@ -372,6 +398,14 @@ static inline void sg_dma_mark_swiotlb(struct scatterlist *sg) { }
+static inline bool sg_dma_is_restricted(struct scatterlist *sg) +{ + return false; +} + +static inline void sg_dma_mark_restrited(struct scatterlist *sg) +{ +} #endif /* CONFIG_NEED_SG_DMA_FLAGS */
/**