xc: export outstanding_pages value in xc_dominfo structure.

This patch provides the value of the currently outstanding pages
claimed for a specific domain. This is a value that influences
the global outstanding claims value (See patch: "xl: 'xl info'
print outstanding claims if enabled") returned via
xc_domain_get_outstanding_pages hypercall. This domain value
decrements as the memory is populated for the guest and
eventually reaches zero.

This patch is neccessary for "xl: export 'outstanding_pages' value
from xcinfo" patch.

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
[v2: s/unclaimed_pages/outstanding_pages/ per Tim's suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

tools/libxc/xc_domain.c

@@ -234,6 +234,7 @@ int xc_domain_getinfo(xc_interface *xch,
 
         info->ssidref  = domctl.u.getdomaininfo.ssidref;
         info->nr_pages = domctl.u.getdomaininfo.tot_pages;
+        info->nr_outstanding_pages = domctl.u.getdomaininfo.outstanding_pages;
         info->nr_shared_pages = domctl.u.getdomaininfo.shr_pages;
         info->nr_paged_pages = domctl.u.getdomaininfo.paged_pages;
         info->max_memkb = domctl.u.getdomaininfo.max_pages << (PAGE_SHIFT-10);

tools/libxc/xenctrl.h

@@ -368,6 +368,7 @@ typedef struct xc_dominfo {
                   hvm:1, debugged:1;
     unsigned int  shutdown_reason; /* only meaningful if shutdown==1 */
     unsigned long nr_pages; /* current number, not maximum */
+    unsigned long nr_outstanding_pages;
     unsigned long nr_shared_pages;
     unsigned long nr_paged_pages;
     unsigned long shared_info_frame;