Another thing, when allocating memory with vmalloc, how can I be sure that the pages I get is
adressable within 4GB (i.e I wan't to call pci_map_sg on this buffer for my 32bit PCI device without
having to use bounce buffers ) ? On systems with less that 4GB of physical memory there's no
problem, but what happens if you have more (lets say an IA64 server with 16GB of RAM) and don't have
an IOMMU (like alpha and sparc) ?
I noticed a vmalloc_32 in linux/vmalloc.h (the comment says "32bit PA addressable pages - eg for PCI
32bit devices"), but is that one platform independent (I see that it is only using GFP_KERNEL, while
vmalloc is using GFP_KERNEL | __GFP_HIGHMEM) ? This issue goes for __get_free_pages too I guess.
Regards,
-- Steffen Persvold | Scalable Linux Systems | Try out the world's best mailto:sp@scali.no | http://www.scali.com | performing MPI implementation: Tel: (+47) 2262 8950 | Olaf Helsets vei 6 | - ScaMPI 1.12.2 - Fax: (+47) 2262 8951 | N0621 Oslo, NORWAY | >300MBytes/s and <4uS latency - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/