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SubjectRe: Removing __kernel_old_uid_t, git_t, dev_t
From: Arnd Bergmann <>
Date: Mon, 30 Mar 2009 17:17:56 +0200

> dma_addr_t is a big mess that was traditionally defined per
> architecture, in lots of wrong ways, including the misconception
> of dma64_addr_t. Sparc64 still uses a 32 bit dma_addr_t, possibly
> because it always uses an IOMMU (?). It can save some space in
> scatterlists, but might come back to bite us if someone tries
> to build a sparc64 system with actual 64-bit DMA.

There is no reason to use anything larger than a 32-bit DMA address
type on sparc64, and using 32-bit saves lots of space in many
data structures so I am unlikely to ever change this. :-)

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