[PATCH 1/3] nvme: add missing unmaps in nvme_queue_rq

[Sagi Grimberg]

On 10/9/2015 7:55 PM, Christoph Hellwig wrote:
> When we fail various metadata related operations in nvme_queue_rq we
> need to unmap the data SGL.
>
> Cc: stable at vger.kernel.org
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
>   drivers/nvme/host/pci.c | 15 ++++++++++++---
>   1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index a526696..0a85fab 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -904,19 +904,28 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
>   			goto retry_cmd;
>   		}
>   		if (blk_integrity_rq(req)) {
> -			if (blk_rq_count_integrity_sg(req->q, req->bio) != 1)
> +			if (blk_rq_count_integrity_sg(req->q, req->bio) != 1) {
> +				dma_unmap_sg(dev->dev, iod->sg, iod->nents,
> +						dma_dir);
>   				goto error_cmd;
> +			}
>
>   			sg_init_table(iod->meta_sg, 1);
>   			if (blk_rq_map_integrity_sg(
> -					req->q, req->bio, iod->meta_sg) != 1)
> +					req->q, req->bio, iod->meta_sg) != 1) {
> +				dma_unmap_sg(dev->dev, iod->sg, iod->nents,
> +						dma_dir);
>   				goto error_cmd;
> +			}
>
>   			if (rq_data_dir(req))
>   				nvme_dif_remap(req, nvme_dif_prep);
>
> -			if (!dma_map_sg(nvmeq->q_dmadev, iod->meta_sg, 1, dma_dir))
> +			if (!dma_map_sg(nvmeq->q_dmadev, iod->meta_sg, 1, dma_dir)) {
> +				dma_unmap_sg(dev->dev, iod->sg, iod->nents,
> +						dma_dir);
>   				goto error_cmd;
> +			}
>   		}
>   	}
>
>

Hi Christoph,

Would it be better to unmap the data sg once at error_cmd tag?