Re: [PATCH] sata_nv: fix ADMA ATAPI issues with memory over 4GB (v2)

[Tejun Heo <htejun@gmail.com>]

Hello, Robert.

Robert Hancock wrote:
> This fixes some problems with ATAPI devices on nForce4 controllers in ADMA
> mode on systems with memory located above 4GB. We need to delay setting the
> 64-bit DMA mask until the PRD table and padding buffer are allocated so that
> they don't get allocated above 4GB and break legacy mode (which is needed for
> ATAPI devices). Also, explicitly set a 32-bit DMA mask before allocating the
> legacy buffers since setting the DMA mask affects both ports and we need to
> ensure the second port's buffers are allocated properly (fixes a problem
> with the previous version of this patch).
> 
> Signed-off-by: Robert Hancock <hancockr@shaw.ca>
> 
> +	/* Ensure DMA mask is set to 32-bit before allocating legacy PRD and
> +	   pad buffers */
> +	pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
> +	pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
[--snip--]
> +	pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
> +	pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));

I'm probably being paranoid here but please add error checks.  Just
checking return value and returning error suffices.

Thanks.

-- 
tejun