2005-12-11 17:18:27

by Imre Deak

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Subject: discontiguous mapping with remap_pfn_range

Hi,

after the recent changes in remap_pfn_range it's not possible any more
to create a mapping for a physically discontiguous range for which no
struct page exists.

Earlier it was achieved by calling remap_pfn_range for each physical
region with the same vma, but now this will result in
incomplete_pfn_remap which handles only normal mappings, that is where
we have struct page for each PFN.

I would need such a mapping for a frame buffer consisting of two
discontiguous physical range. Is there any way I can do this with the
current API? If not, is there a plan to support it (with a vm_insert_pfn
for example) ? I know it's a rare HW configuration, but there might be
some other use case for this.

Thanks,
Imre