From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: [PATCH 1/5] swiotlb: Introduce swiotlb_max_mapping_size() Date: Wed, 30 Jan 2019 17:40:03 +0100 Message-ID: <20190130164007.26497-2-joro@8bytes.org> References: <20190130164007.26497-1-joro@8bytes.org> Return-path: In-Reply-To: <20190130164007.26497-1-joro@8bytes.org> Sender: linux-kernel-owner@vger.kernel.org To: "Michael S . Tsirkin" , Jason Wang , Konrad Rzeszutek Wilk , Christoph Hellwig Cc: Jens Axboe , virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, jfehlig@suse.com, jon.grimm@amd.com, brijesh.singh@amd.com, joro@8bytes.org, jroedel@suse.de, Thomas.Lendacky@amd.com List-Id: iommu@lists.linux-foundation.org From: Joerg Roedel 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 Reviewed-by: Christoph Hellwig Signed-off-by: Joerg Roedel --- 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