5.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: Joerg Roedel jroedel@suse.de
commit abe420bfae528c92bd8cc5ecb62dc95672b1fd6f upstream.
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.
Cc: stable@vger.kernel.org Reviewed-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Michael S. Tsirkin mst@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/linux/swiotlb.h | 5 +++++ kernel/dma/swiotlb.c | 5 +++++ 2 files changed, 10 insertions(+)
--- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -76,6 +76,7 @@ bool swiotlb_map(struct device *dev, phy size_t size, enum dma_data_direction dir, unsigned long attrs); void __init swiotlb_exit(void); unsigned int swiotlb_max_segment(void); +size_t swiotlb_max_mapping_size(struct device *dev); #else #define swiotlb_force SWIOTLB_NO_FORCE static inline bool is_swiotlb_buffer(phys_addr_t paddr) @@ -95,6 +96,10 @@ static inline unsigned int swiotlb_max_s { 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); --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -662,3 +662,8 @@ swiotlb_dma_supported(struct device *hwd { 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; +}