Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-07-04 Thread Robin Murphy
On 2022-06-15 17:12, Logan Gunthorpe wrote: Make use of the third free LSB in scatterlist's page_link on 64bit systems. The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a given SGL segments dma_address points to a PCI bus address. dma_unmap_sg_p2pdma() will need to perform

Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-29 Thread Logan Gunthorpe
On 2022-06-29 12:02, Robin Murphy wrote: > On 2022-06-29 16:39, Logan Gunthorpe wrote: >> On 2022-06-29 03:05, Robin Murphy wrote: >>> On 2022-06-15 17:12, Logan Gunthorpe wrote: >>> Does this serve any useful purpose? If a page is determined to be device >>> memory, it's not going to suddenly s

Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-29 Thread Robin Murphy
On 2022-06-29 16:39, Logan Gunthorpe wrote: On 2022-06-29 03:05, Robin Murphy wrote: On 2022-06-15 17:12, Logan Gunthorpe wrote: Make use of the third free LSB in scatterlist's page_link on 64bit systems. The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a given SGL se

Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-29 Thread Logan Gunthorpe
On 2022-06-29 03:05, Robin Murphy wrote: > On 2022-06-15 17:12, Logan Gunthorpe wrote: >> Make use of the third free LSB in scatterlist's page_link on 64bit >> systems. >> >> The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a >> given SGL segments dma_address points to a P

Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-29 Thread Robin Murphy
On 2022-06-15 17:12, Logan Gunthorpe wrote: Make use of the third free LSB in scatterlist's page_link on 64bit systems. The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a given SGL segments dma_address points to a PCI bus address. dma_unmap_sg_p2pdma() will need to perform

Re: [PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-28 Thread Christoph Hellwig
On Wed, Jun 15, 2022 at 10:12:13AM -0600, Logan Gunthorpe wrote: > Make use of the third free LSB in scatterlist's page_link on 64bit systems. > > The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a > given SGL segments dma_address points to a PCI bus address. > dma_unmap_sg_

[PATCH v7 01/21] lib/scatterlist: add flag for indicating P2PDMA segments in an SGL

2022-06-15 Thread Logan Gunthorpe
Make use of the third free LSB in scatterlist's page_link on 64bit systems. The extra bit will be used by dma_[un]map_sg_p2pdma() to determine when a given SGL segments dma_address points to a PCI bus address. dma_unmap_sg_p2pdma() will need to perform different cleanup when a segment is marked as