Gregory Haskins wrote: > On Fri, 2007-08-10 at 19:59 +0300, Avi Kivity wrote: > > >> Note that passing a virtual address is highly discouraged as its meaning >> can change from vcpu to vcpu, it might not be mapped, translation is >> slow, etc. Just let the guest do the translation. >> > > Yeah, Hollis and Anthony straighted me out via IRC. I will mostly be > dealing with kmalloc/skb buffers so we settled on the following as > optimal: > > guest-side > > gpa = __pa(ptr); > > host-side: > > gfn = gpa >> PAGE_SHIFT > page = gfn_to_page(gfn); > ptr = kmap(page); > > .. > > kunmap(ptr); >
kmap can sleep so you often have to use kmap_atomic in KVM. Although, I'm not sure if the pre-emption notification means that no longer is the case. Regards, Anthony Liguori > >> We have something running at qumranet, will be sent out soon. I am >> somewhat discouraged in trying to get the thing to page -- Shaohua's >> approach is much simpler. >> >> > > Cool! Ill keep an eye out. > > -Greg > > > ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
