Messages in this thread | | | Subject | Re: [PATCH 13/16] nvme-pci: Convert to using dma_map_sg_p2pdma for p2pdma pages | From | John Hubbard <> | Date | Mon, 3 May 2021 17:26:57 -0700 |
| |
On 5/3/21 10:19 AM, Logan Gunthorpe wrote: ... >>> + nr_mapped = dma_map_sg_p2pdma_attrs(dev->dev, iod->sg, iod->nents, >>> + rq_dma_dir(req), DMA_ATTR_NO_WARN); >>> + if (nr_mapped < 0) { >>> + if (nr_mapped != -ENOMEM) >>> + ret = BLK_STS_TARGET; >>> goto out_free_sg; >>> + } >> >> But now the "nr_mapped == 0" case is no longer doing an early out_free_sg. >> Is that OK? > > dma_map_sg_p2pdma_attrs() never returns zero. It will return -ENOMEM in > the same situation and results in the same goto out_free_sg. >
OK...that's true, it doesn't return zero. A comment or WARN or something might be nice, to show that the zero case hasn't been overlooked. It's true that the dma_map_sg_p2pdma_attrs() documentation sort of says that (although not quite out loud).
thanks, -- John Hubbard NVIDIA
| |