Re: [PATCH 1/4] add is_buffer_dma_capable helper function

From: Joerg Roedel
Date: Tue Sep 09 2008 - 12:21:49 EST

On Tue, Sep 09, 2008 at 09:17:05AM -0700, Luck, Tony wrote:
> +static inline int is_buffer_dma_capable(u64 mask, dma_addr_t addr, size_t size)
> +{
> + return addr + size <= mask;
> +}
> Do we care about wrap-around (e.g. addr=0xffffffffffffffff size=2)?

I don't think so. The current code does not care about it and if it
happens its a bug in the iommu implementation.


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