From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 22:31:20 +0000 (+0100) Subject: xen: efficiently support a holey p2m table X-Git-Tag: v2.6.27-rc1~1106^2~251^24~25 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf0923ea295ba08ae656ef04164a43cb6553ba99;p=pandora-kernel.git xen: efficiently support a holey p2m table When using sparsemem and memory hotplug, the kernel's pseudo-physical address space can be discontigious. Previously this was dealt with by having the upper parts of the radix tree stubbed off. Unfortunately, this is incompatible with save/restore, which requires a complete p2m table. The solution is to have a special distinguished all-invalid p2m leaf page, which we can point all the hole areas at. This allows the tools to see a complete p2m table, but it only costs a page for all memory holes. It also simplifies the code since it removes a few special cases. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- Reading git-diff-tree failed