Re: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
From: Christoph Hellwig <hch@lst.de>
Date: 2021-06-16 05:18:47
Also in:
intel-gfx, linux-devicetree, linux-iommu, linux-pci, lkml, xen-devel
On Wed, Jun 16, 2021 at 01:10:02PM +0800, Claire Chang wrote:
On Wed, Jun 16, 2021 at 12:59 PM Christoph Hellwig [off-list ref] wrote:quoted
On Wed, Jun 16, 2021 at 12:04:16PM +0800, Claire Chang wrote:quoted
Just noticed that after propagating swiotlb_force setting into io_tlb_default_mem->force, the memory allocation behavior for swiotlb_force will change (i.e. always skipping arch_dma_alloc and dma_direct_alloc_from_pool).Yes, I think we need to split a "use_for_alloc" flag from the force flag.How about splitting is_dev_swiotlb_force into is_swiotlb_force_bounce (io_tlb_mem->force_bounce) and is_swiotlb_force_alloc (io_tlb_mem->force_alloc)?
Yes, something like that. I'd probably not use force for the alloc side given that we otherwise never allocte from the swiotlb buffer.