Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH v2 27/32] scsi: hisi_sas: add smp protocol support | Date | Mon, 02 Nov 2015 21:29:50 +0100 |
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On Monday 02 November 2015 17:03:58 John Garry wrote: > > > > Can do. Actually sg_req seems only ever has one element: > > expander.c, smp_execute_task() > > sg_init_one(&task->smp_task.smp_req, req, req_size); > > > > > I tried replacing with dma_map_single, but I feel the code is not as > clean as I need to manually set sg_dma_len() and sg_dma_address(): > req_len = sg_dma_len(sg_req) = sg_req->length; > sg_dma_address(sg_req) = dma_map_single(dev, sg_virt(sg_req), > req_len, DMA_TO_DEVICE); > if (dma_mapping_error(dev, sg_dma_address(sg_req))) > return -ENOMEM; > sg_dma_address(sg_req) is used in another function for unmap. > > opinion? >
What I meant was not using a struct scatterlist at all: replace the 'sg_req' variable with a normal pointer, and then do
hdr->cmd_table_addr = cpu_to_le64(dma_map_single(dev, req, len, DMA_TO_DEVICE));
Any reason this won't work?
Arnd
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