diff options
| author | Christoph Lameter <clameter@sgi.com> | 2007-02-10 01:43:09 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-11 10:51:18 -0800 |
| commit | 66701b1499a3ff11882c8c4aef36e8eac86e17b1 (patch) | |
| tree | 7900ced6b590c3cd939bcdc92355ff0a14f856e3 /mm | |
| parent | 6267276f3fdda9ad0d5ca451bdcbdf42b802d64b (diff) | |
| download | lwn-66701b1499a3ff11882c8c4aef36e8eac86e17b1.tar.gz lwn-66701b1499a3ff11882c8c4aef36e8eac86e17b1.zip | |
[PATCH] optional ZONE_DMA: 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.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/Kconfig | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index db7c55de92cd..50f7cfc15b78 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -139,6 +139,10 @@ config SPLIT_PTLOCK_CPUS default "4096" if PARISC && !PA20 default "4" +config ZONE_DMA + def_bool y + depends on GENERIC_ISA_DMA + # # support for page migration # |