5ac6da669e
As Andi pointed out: CONFIG_GENERIC_ISA_DMA only disables the ISA DMA channel management. Other functionality may still expect GFP_DMA to provide memory below 16M. So we need to make sure that CONFIG_ZONE_DMA is set independent of CONFIG_GENERIC_ISA_DMA. Undo the modifications to mm/Kconfig where we made ZONE_DMA dependent on GENERIC_ISA_DMA and set theses explicitly in each arches Kconfig. Reviews must occur for each arch in order to determine if ZONE_DMA can be switched off. It can only be switched off if we know that all devices supported by a platform are capable of performing DMA transfers to all of memory (Some arches already support this: uml, avr32, sh sh64, parisc and IA64/Altix). In order to switch ZONE_DMA off conditionally, one would have to establish a scheme by which one can assure that no drivers are enabled that are only capable of doing I/O to a part of memory, or one needs to provide an alternate means of performing an allocation from a specific range of memory (like provided by alloc_pages_range()) and insure that all drivers use that call. In that case the arches alloc_dma_coherent() may need to be modified to call alloc_pages_range() instead of relying on GFP_DMA. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| boot | ||
| common | ||
| configs | ||
| kernel | ||
| lib | ||
| mach-aaec2000 | ||
| mach-at91rm9200 | ||
| mach-clps711x | ||
| mach-clps7500 | ||
| mach-ebsa110 | ||
| mach-ep93xx | ||
| mach-footbridge | ||
| mach-h720x | ||
| mach-imx | ||
| mach-integrator | ||
| mach-iop13xx | ||
| mach-iop32x | ||
| mach-iop33x | ||
| mach-ixp4xx | ||
| mach-ixp23xx | ||
| mach-ixp2000 | ||
| mach-l7200 | ||
| mach-lh7a40x | ||
| mach-netx | ||
| mach-omap1 | ||
| mach-omap2 | ||
| mach-pnx4008 | ||
| mach-pxa | ||
| mach-realview | ||
| mach-rpc | ||
| mach-s3c2410 | ||
| mach-sa1100 | ||
| mach-shark | ||
| mach-versatile | ||
| mm | ||
| nwfpe | ||
| oprofile | ||
| plat-iop | ||
| plat-omap | ||
| tools | ||
| vfp | ||
| Kconfig | ||
| Kconfig-nommu | ||
| Kconfig.debug | ||
| Makefile | ||