Hi, On 2024/10/7 18:17, Lucas Stach wrote:
@@ -104,21 +108,7 @@ static int etnaviv_iommu_map(struct etnaviv_iommu_context *context, u32 iova,static void etnaviv_iommu_unmap(struct etnaviv_iommu_context *context, u32 iova, struct sg_table *sgt, unsigned len) { - struct scatterlist *sg; - unsigned int da = iova; - int i; - - for_each_sgtable_dma_sg(sgt, sg, i) { - size_t bytes = sg_dma_len(sg) + sg->offset;
Why the length of a single SG segment is `sg_dma_len(sg) + sg->offset` here?
- etnaviv_context_unmap(context, da, bytes); - - VERB("unmap[%d]: %08x(%zx)", i, iova, bytes); - - BUG_ON(!PAGE_ALIGNED(bytes)); - - da += bytes; - } + etnaviv_context_unmap(context, iova, len);This drops some sanity checks, but I have only ever seen them fire when we had other kernel memory corruption issues, so I'm fine with the simplification you did here.
Isn't that 'sg_dma_len(sg)' itself is the length of its backing memory ?
Regards, Lucas
-- Best regards, Sui
