Messages in this thread | | | From | "Adam J. Richter" <> | Date | Tue, 5 Mar 2002 03:52:14 -0800 | Subject | Re: Does kmalloc always return address below 4GB? |
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>Just use pci_alloc_consistent, it never gives you >anything larger than 32-bit addresses, please read the >documentation :-)
I see the smiley, but let me point out that I have read Documentation/DMA-mapping.txt and I was misled by this sentence:
| If you acquired your memory via the page allocator | (i.e. __get_free_page*()) or the generic memory allocators | (i.e. kmalloc() or kmem_cache_alloc()) then you may DMA to/from | that memory using the addresses returned from those routines.
It might be a good idea to rephrase it. If I knew what that sentence I would propose a patch to the DMA-mapping.txt file, but I honestly don't know what proposition that sentence is supposed to convey. If there really is no guarantee that this sentence is conveying, then I guess the sentence should be deleted.
Anyhow, thanks for your quick clarification. The driver breaking on 64-bit architectures was exactly what I was worried about.
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