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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.. | ||
allocpercpu.c | ||
backing-dev.c | ||
bootmem.c | ||
bounce.c | ||
fadvise.c | ||
filemap.c | ||
filemap.h | ||
filemap_xip.c | ||
fremap.c | ||
highmem.c | ||
hugetlb.c | ||
internal.h | ||
Kconfig | ||
madvise.c | ||
Makefile | ||
memory.c | ||
memory_hotplug.c | ||
mempolicy.c | ||
mempool.c | ||
migrate.c | ||
mincore.c | ||
mlock.c | ||
mmap.c | ||
mmzone.c | ||
mprotect.c | ||
mremap.c | ||
msync.c | ||
nommu.c | ||
oom_kill.c | ||
page-writeback.c | ||
page_alloc.c | ||
page_io.c | ||
pdflush.c | ||
prio_tree.c | ||
readahead.c | ||
rmap.c | ||
shmem.c | ||
shmem_acl.c | ||
slab.c | ||
slob.c | ||
sparse.c | ||
swap.c | ||
swap_state.c | ||
swapfile.c | ||
thrash.c | ||
tiny-shmem.c | ||
truncate.c | ||
util.c | ||
vmalloc.c | ||
vmscan.c | ||
vmstat.c |