Messages in this thread | | | Date | Tue, 7 Nov 2017 09:03:29 -0700 | From | Jason Gunthorpe <> | Subject | Re: [PATCH for-next 2/4] RDMA/hns: Add IOMMU enable support in hip08 |
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On Tue, Nov 07, 2017 at 07:58:05AM -0800, Christoph Hellwig wrote: > On Tue, Nov 07, 2017 at 08:48:38AM -0700, Jason Gunthorpe wrote: > > Can't you just use vmalloc and dma_map that? Other drivers follow that > > approach.. > > You can't easily due to the flushing requirements. We used to do that > in XFS and it led to problems. You need the page allocator + vmap + > invalidate_kernel_vmap_range + flush_kernel_vmap_range to get the > cache flushing right.
Yes, exactly something ugly like that.. :\
Jason
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