[PATCH] Fix uses of dma_max_pfn() when converting to a limiting address

[Russell King - ARM Linux]

On Thu, Feb 13, 2014 at 08:58:10AM -0800, James Bottomley wrote:
> This doesn't really look like the right fix.  You replaced dev->dma_mask
> with a calculation on dev_max_pfn().  Since dev->dma_mask is always u64
> and dev_max_pfn is supposed to be returning the pfn of the dma_mask, it
> should unconditionally be 64 bits as well.  Either that or it should
> return dma_addr_t.

My reasoning is that PFNs in the system are always of type "unsigned long"
and therefore a function returning a pfn should have that type.  If we
overflow a PFN fitting in an unsigned long, we have lots of places which
need fixing.

-- 
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Estimate before purchase was "up to 13.2Mbit".