diff options
Diffstat (limited to 'include/linux/scatterlist.h')
| -rw-r--r-- | include/linux/scatterlist.h | 84 |
1 files changed, 72 insertions, 12 deletions
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h index 375a5e90d86a..77df3d7b18a6 100644 --- a/include/linux/scatterlist.h +++ b/include/linux/scatterlist.h @@ -16,7 +16,7 @@ struct scatterlist { #ifdef CONFIG_NEED_SG_DMA_LENGTH unsigned int dma_length; #endif -#ifdef CONFIG_PCI_P2PDMA +#ifdef CONFIG_NEED_SG_DMA_FLAGS unsigned int dma_flags; #endif }; @@ -141,6 +141,30 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page, sg->length = len; } +/** + * sg_set_folio - Set sg entry to point at given folio + * @sg: SG entry + * @folio: The folio + * @len: Length of data + * @offset: Offset into folio + * + * Description: + * Use this function to set an sg entry pointing at a folio, never assign + * the folio directly. We encode sg table information in the lower bits + * of the folio pointer. See sg_page() for looking up the page belonging + * to an sg entry. + * + **/ +static inline void sg_set_folio(struct scatterlist *sg, struct folio *folio, + size_t len, size_t offset) +{ + WARN_ON_ONCE(len > UINT_MAX); + WARN_ON_ONCE(offset > UINT_MAX); + sg_assign_page(sg, &folio->page); + sg->offset = offset; + sg->length = len; +} + static inline struct page *sg_page(struct scatterlist *sg) { #ifdef CONFIG_DEBUG_SG @@ -249,17 +273,18 @@ static inline void sg_unmark_end(struct scatterlist *sg) } /* - * CONFGI_PCI_P2PDMA depends on CONFIG_64BIT which means there is 4 bytes - * in struct scatterlist (assuming also CONFIG_NEED_SG_DMA_LENGTH is set). - * Use this padding for DMA flags bits to indicate when a specific - * dma address is a bus address. + * One 64-bit architectures there is a 4-byte padding in struct scatterlist + * (assuming also CONFIG_NEED_SG_DMA_LENGTH is set). Use this padding for DMA + * flags bits to indicate when a specific dma address is a bus address or the + * buffer may have been bounced via SWIOTLB. */ -#ifdef CONFIG_PCI_P2PDMA +#ifdef CONFIG_NEED_SG_DMA_FLAGS -#define SG_DMA_BUS_ADDRESS (1 << 0) +#define SG_DMA_BUS_ADDRESS (1 << 0) +#define SG_DMA_SWIOTLB (1 << 1) /** - * sg_dma_is_bus address - Return whether a given segment was marked + * sg_dma_is_bus_address - Return whether a given segment was marked * as a bus address * @sg: SG entry * @@ -267,13 +292,13 @@ static inline void sg_unmark_end(struct scatterlist *sg) * Returns true if sg_dma_mark_bus_address() has been called on * this segment. **/ -static inline bool sg_is_dma_bus_address(struct scatterlist *sg) +static inline bool sg_dma_is_bus_address(struct scatterlist *sg) { return sg->dma_flags & SG_DMA_BUS_ADDRESS; } /** - * sg_dma_mark_bus address - Mark the scatterlist entry as a bus address + * sg_dma_mark_bus_address - Mark the scatterlist entry as a bus address * @sg: SG entry * * Description: @@ -299,9 +324,37 @@ static inline void sg_dma_unmark_bus_address(struct scatterlist *sg) sg->dma_flags &= ~SG_DMA_BUS_ADDRESS; } +/** + * sg_dma_is_swiotlb - Return whether the scatterlist was marked for SWIOTLB + * bouncing + * @sg: SG entry + * + * Description: + * Returns true if the scatterlist was marked for SWIOTLB bouncing. Not all + * elements may have been bounced, so the caller would have to check + * individual SG entries with is_swiotlb_buffer(). + */ +static inline bool sg_dma_is_swiotlb(struct scatterlist *sg) +{ + return sg->dma_flags & SG_DMA_SWIOTLB; +} + +/** + * sg_dma_mark_swiotlb - Mark the scatterlist for SWIOTLB bouncing + * @sg: SG entry + * + * Description: + * Marks a a scatterlist for SWIOTLB bounce. Not all SG entries may be + * bounced. + */ +static inline void sg_dma_mark_swiotlb(struct scatterlist *sg) +{ + sg->dma_flags |= SG_DMA_SWIOTLB; +} + #else -static inline bool sg_is_dma_bus_address(struct scatterlist *sg) +static inline bool sg_dma_is_bus_address(struct scatterlist *sg) { return false; } @@ -311,8 +364,15 @@ static inline void sg_dma_mark_bus_address(struct scatterlist *sg) static inline void sg_dma_unmark_bus_address(struct scatterlist *sg) { } +static inline bool sg_dma_is_swiotlb(struct scatterlist *sg) +{ + return false; +} +static inline void sg_dma_mark_swiotlb(struct scatterlist *sg) +{ +} -#endif +#endif /* CONFIG_NEED_SG_DMA_FLAGS */ /** * sg_phys - Return physical address of an sg entry |