Re: [PATCH] nvme-pci: Set min align mask before calculating max_hw_sectors

[Sagi Grimberg]

> If swiotlb is force enabled dma_max_mapping_size ends up calling
> swiotlb_max_mapping_size which takes into account the min align
> mask for the device.
> Set the min align mask for nvme driver before calling
> dma_max_mapping_size while calculating max hw sectors.

Does this fix a specific bug? if so it needs a fixes tag so it can
go to stable backports as well.

> Signed-off-by: Rishabh Bhatnagar <risbhat@xxxxxxxxxx>
> ---
>   drivers/nvme/host/pci.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 98864b853eef..30e71e41a0a2 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -2834,6 +2834,8 @@ static void nvme_reset_work(struct work_struct *work)
>   		nvme_start_admin_queue(&dev->ctrl);
>   	}
>   
> +	dma_set_min_align_mask(dev->dev, NVME_CTRL_PAGE_SIZE - 1);
> +
>   	/*
>   	 * Limit the max command size to prevent iod->sg allocations going
>   	 * over a single page.
> @@ -2846,7 +2848,6 @@ static void nvme_reset_work(struct work_struct *work)
>   	 * Don't limit the IOMMU merged segment size.
>   	 */
>   	dma_set_max_seg_size(dev->dev, 0xffffffff);
> -	dma_set_min_align_mask(dev->dev, NVME_CTRL_PAGE_SIZE - 1);
>   
>   	mutex_unlock(&dev->shutdown_lock);
>