[Q] comedi: vmap of the async->prealloc_buf

H Hartley Sweeten hartleys at visionengravers.com
Thu Dec 20 17:09:13 UTC 2012

Hello all,

I have a question...

In the comedi core, the asynchronous 'prealloc_buf' is vmap'ed after
the page list has been allocated. The code in question looks like this:

			async->prealloc_buf =
				vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE);
				vmap(pages, n_pages, VM_MAP, PAGE_KERNEL);

Is the #ifdef something left over from an older kernel?

Isn't PAGE_KERNEL_NOCACHE always defined?

Thanks for any insight,

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