Re: [never mind] kiobufs and highmem

From: Gerd Knorr (kraxel@bytesex.org)
Date: Tue Jul 23 2002 - 06:17:33 EST

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In reply to: Ingo Oeser: "Re: [never mind] kiobufs and highmem"
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> This should work. If you have highmem pages and your device can't
> handle >32-bit physical addresses, then kmap() them
> before pci_map_sg()ing them and kunmap() them after
> pci_unmap_sg()ing.

--verbose please, I don't see how kmap() will fix the 32-bit limit issue.

As far I know kmap() doesn't move the page in physical memory, but
creates a virtual mapping for it. Thus the kernel (i.e. the CPU) can
access it, but PCI busmasters still can't ...

Gerd

-- 
You can't please everybody.  And usually if you _try_ to please
everybody, the end result is one big mess.
				-- Linus Torvalds, 2002-04-20
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Next message: Neil Brown: "PATCH: type safe(r) list_entry repacement: generic_out_cast"
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In reply to: Ingo Oeser: "Re: [never mind] kiobufs and highmem"
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