On Mon, Sep 11, 2006 at 03:27:39PM -0700, Christoph Lameter wrote: > Introduce CONFIG_ZONE_DMA > > This patch simply defines CONFIG_ZONE_DMA for all arches. We later do > special things with CONFIG_ZONE_DMA after the VM and an arch are > prepared to work without ZONE_DMA. > > CONFIG_ZONE_DMA can be defined in two ways depending on how > an architecture handles ISA DMA. > > First if CONFIG_GENERIC_ISA_DMA is set by the arch then we know that > the arch needs ZONE_DMA because ISA DMA devices are supported. We > can catch this in mm/Kconfig and do not need to modify arch code. > > Second, arches may use ZONE_DMA in an unknown way. We set CONFIG_ZONE_DMA > for all arches that do not set CONFIG_GENERIC_ISA_DMA in order to insure > backwards compatibility. The arches may later undefine ZONE_DMA > if their arch code has been verified to not depend on ZONE_DMA. Let's pass this on to linux-arch so that the arch maintainers can give input whether they need ZONE_DMA or not. If this just sneaks in unseen I'd bet various architectures will just keept it around despite not needing it. - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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