[PATCH 1/5] swiotlb: Introduce swiotlb_max_mapping_size()
From: Joerg Roedel <joro@8bytes.org>
Date: 2019-01-29 08:44:17
Also in:
linux-iommu, lkml
Subsystem:
dma mapping helpers, the rest · Maintainers:
Marek Szyprowski, Linus Torvalds
From: Joerg Roedel <redacted> The function returns the maximum size that can be remapped by the SWIOTLB implementation. This function will be later exposed to users through the DMA-API. Reviewed-by: Konrad Rzeszutek Wilk <redacted> Signed-off-by: Joerg Roedel <redacted> --- include/linux/swiotlb.h | 5 +++++ kernel/dma/swiotlb.c | 5 +++++ 2 files changed, 10 insertions(+)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 7c007ed7505f..1c22d96e1742 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h@@ -62,6 +62,7 @@ extern void swiotlb_tbl_sync_single(struct device *hwdev, extern int swiotlb_dma_supported(struct device *hwdev, u64 mask); +size_t swiotlb_max_mapping_size(struct device *dev); #ifdef CONFIG_SWIOTLB extern enum swiotlb_force swiotlb_force;
@@ -95,6 +96,10 @@ static inline unsigned int swiotlb_max_segment(void) { return 0; } +static inline size_t swiotlb_max_mapping_size(struct device *dev) +{ + return SIZE_MAX; +} #endif /* CONFIG_SWIOTLB */ extern void swiotlb_print_info(void);
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 1fb6fd68b9c7..9cb21259cb0b 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c@@ -662,3 +662,8 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask) { return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask; } + +size_t swiotlb_max_mapping_size(struct device *dev) +{ + return ((size_t)1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE; +}
--
2.17.1