Re: [PATCH 2/8] NTB: Setup the DMA mask globally for all drivers

[Dave Jiang]

On 06/08/2018 05:08 PM, Logan Gunthorpe wrote:
> Commit  417cf39cfea9 ("NTB: Set dma mask and dma coherent mask to NTB
> devices") added code to set the DMA mask for the NTB device
> to each driver individually. However, it neglected to set it for the
> Switchtec driver. So when the monolithic commit 7f46c8b3a552 ("NTB:
> ntb_tool: Add full multi-port NTB API support") started allocating
> DMA memory against the NTB device it broke the Switchtec driver.
> 
> Seeing this is setting up a property of the NTB device, it should be
> done by the common NTB code (inside ntb_register_device()) so we can be
> sure it's done properly for all drivers. This avoids each driver needing
> to duplicate the code and helps prevent us from inadvertently breaking
> one of the drivers in the future if we have to make changes in this area.
> 
> Fixes: 7f46c8b3a552 ("NTB: ntb_tool: Add full multi-port NTB API support")
> Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>

Acked-by: Dave Jiang <dave.jiang@xxxxxxxxx>
for the Intel parts and the generic parts

> ---
>  drivers/ntb/hw/amd/ntb_hw_amd.c     |  4 ----
>  drivers/ntb/hw/idt/ntb_hw_idt.c     |  6 ------
>  drivers/ntb/hw/intel/ntb_hw_intel.c |  4 ----
>  drivers/ntb/ntb.c                   | 13 ++++++++++++-
>  4 files changed, 12 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c
> index 3cfa46876239..f0788aae05c9 100644
> --- a/drivers/ntb/hw/amd/ntb_hw_amd.c
> +++ b/drivers/ntb/hw/amd/ntb_hw_amd.c
> @@ -1020,10 +1020,6 @@ static int amd_ntb_init_pci(struct amd_ntb_dev *ndev,
>  			goto err_dma_mask;
>  		dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n");
>  	}
> -	rc = dma_coerce_mask_and_coherent(&ndev->ntb.dev,
> -					  dma_get_mask(&pdev->dev));
> -	if (rc)
> -		goto err_dma_mask;
>  
>  	ndev->self_mmio = pci_iomap(pdev, 0, 0);
>  	if (!ndev->self_mmio) {
> diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c
> index 8d98872d0983..1918a2db1c43 100644
> --- a/drivers/ntb/hw/idt/ntb_hw_idt.c
> +++ b/drivers/ntb/hw/idt/ntb_hw_idt.c
> @@ -2447,12 +2447,6 @@ static int idt_init_pci(struct idt_ntb_dev *ndev)
>  		dev_warn(&pdev->dev,
>  			"Cannot set consistent DMA highmem bit mask\n");
>  	}
> -	ret = dma_coerce_mask_and_coherent(&ndev->ntb.dev,
> -					   dma_get_mask(&pdev->dev));
> -	if (ret != 0) {
> -		dev_err(&pdev->dev, "Failed to set NTB device DMA bit mask\n");
> -		return ret;
> -	}
>  
>  	/*
>  	 * Enable the device advanced error reporting. It's not critical to
> diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c
> index 156b45cd4a19..341a3d5baa3f 100644
> --- a/drivers/ntb/hw/intel/ntb_hw_intel.c
> +++ b/drivers/ntb/hw/intel/ntb_hw_intel.c
> @@ -2334,10 +2334,6 @@ static int intel_ntb_init_pci(struct intel_ntb_dev *ndev, struct pci_dev *pdev)
>  			goto err_dma_mask;
>  		dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n");
>  	}
> -	rc = dma_coerce_mask_and_coherent(&ndev->ntb.dev,
> -					  dma_get_mask(&pdev->dev));
> -	if (rc)
> -		goto err_dma_mask;
>  
>  	ndev->self_mmio = pci_iomap(pdev, 0, 0);
>  	if (!ndev->self_mmio) {
> diff --git a/drivers/ntb/ntb.c b/drivers/ntb/ntb.c
> index 2581ab724c34..93f24440d11d 100644
> --- a/drivers/ntb/ntb.c
> +++ b/drivers/ntb/ntb.c
> @@ -100,6 +100,8 @@ EXPORT_SYMBOL(ntb_unregister_client);
>  
>  int ntb_register_device(struct ntb_dev *ntb)
>  {
> +	int ret;
> +
>  	if (!ntb)
>  		return -EINVAL;
>  	if (!ntb->pdev)
> @@ -120,7 +122,16 @@ int ntb_register_device(struct ntb_dev *ntb)
>  	ntb->ctx_ops = NULL;
>  	spin_lock_init(&ntb->ctx_lock);
>  
> -	return device_register(&ntb->dev);
> +	device_initialize(&ntb->dev);
> +
> +	ret = dma_coerce_mask_and_coherent(&ntb->dev,
> +					   dma_get_mask(&ntb->pdev->dev));
> +	if (ret != 0) {
> +		dev_err(&ntb->dev, "Failed to set NTB device DMA bit mask\n");
> +		return ret;
> +	}
> +
> +	return device_add(&ntb->dev);
>  }
>  EXPORT_SYMBOL(ntb_register_device);
>  
>