uint64_t xen_memshare(xen_interface_t *xen, domid_t domID, domid_t cloneID) {
uint64_t shared = 0;
#if __XEN_INTERFACE_VERSION__ < 0x00040600
uint64_t page, max_page = xc_domain_maximum_gpfn(xen->xc, domID);
#else
xen_pfn_t page, max_page;
if (xc_domain_maximum_gpfn(xen->xc, domID, &max_page)) {
printf("Failed to get max gpfn from Xen!\n");
goto done;
}
#endif
if (!max_page) {
printf("Failed to get max gpfn!\n");
goto done;
}
if (xc_memshr_control(xen->xc, domID, 1)) {
printf("Failed to enable memsharing on origin!\n");
goto done;
}
if (xc_memshr_control(xen->xc, cloneID, 1)) {
printf("Failed to enable memsharing on clone!\n");
goto done;
}
/*
* page will underflow when done
*/
for (page = max_page; page <= max_page; page--) {
uint64_t shandle, chandle;
if (xc_memshr_nominate_gfn(xen->xc, domID, page, &shandle))
continue;
if (xc_memshr_nominate_gfn(xen->xc, cloneID, page, &chandle))
continue;
if (xc_memshr_share_gfns(xen->xc, domID, page, shandle, cloneID, page,
chandle))
continue;
shared++;
}
done: return shared;
}
int main(int argc, char **argv) {
if (argc < 3) {
printf("Usage: %s origin-domID clone-domID\n", argv[0]);
return 1;
}
domid_t origin = atoi(argv[1]), clone = atoi(argv[2]);
xc_interface *xc = xc_interface_open(0, 0, 0);
vcpu_guest_context_any_t vcpu_context;
uint32_t hvm_context_size;
uint8_t *hvm_context;
if (xc == NULL) {
fprintf(stderr, "xc_interface_open() failed!\n");
return 0;
}
if (xc_vcpu_getcontext(xc, origin, 0, &vcpu_context)) {
printf("Failed to get the VCPU context of domain %u\n", origin);
return 1;
}
printf("Setting VCPU context of clone\n");
if (xc_vcpu_setcontext(xc, clone, 0, &vcpu_context)) {
printf("Failed to set the VCPU context of domain %u\n", clone);
}
/*printf("Setting HVM parameters of clone\n");
int hvm_param_copy = 0;
while (hvm_param_copy < HVM_PARAM_COUNT) {
unsigned long value = 0;
xc_get_hvm_param(xc, origin, hvm_params[hvm_param_copy], &value);
if (value) {
switch (hvm_params[hvm_param_copy]) {
case HVM_PARAM_CONSOLE_PFN:
case HVM_PARAM_IOREQ_PFN:
case HVM_PARAM_BUFIOREQ_PFN:
case HVM_PARAM_STORE_PFN:
break;
default:
printf("Setting HVM param %i with value %lu\n",
hvm_params[hvm_param_copy], value);
xc_set_hvm_param(xc, clone, hvm_params[hvm_param_copy], value);
break;
}
}
hvm_param_copy++;
}*/
hvm_context_size = xc_domain_hvm_getcontext(xc, origin, NULL, 0);
if (hvm_context_size <= 0) {
printf("HVM context size <= 0. Not an HVM domain?\n");
return 1;
}
hvm_context = malloc(hvm_context_size * sizeof(uint8_t));
if (xc_domain_hvm_getcontext(xc, origin, hvm_context, hvm_context_size)
<= 0) {
printf("Failed to get HVM context.\n");
return 1;
}
xc_dominfo_t info;
xc_domain_getinfo(xc, origin, 1, &info);
int page = xc_domain_maximum_gpfn(xc, origin) + 1;
printf("Sharing memory.. Origin domain has %lu kb ram and %i pages.\n",
info.max_memkb, page);
xc_memshr_control(xc, origin, 1);
xc_memshr_control(xc, clone, 1);
uint64_t shandle, chandle;
int shared = 0;
while (page >= 0) {
page--;
if (xc_memshr_nominate_gfn(xc, origin, page, &shandle)) {
continue;
}
if (xc_memshr_nominate_gfn(xc, clone, page, &chandle)) {
continue;
}
if (xc_memshr_share_gfns(xc, origin, page, shandle, clone, page,
chandle))
continue;
shared++;
}
printf("Shared %i pages\n", shared);
/*hvm_param_copy = 0;
while (hvm_param_copy < HVM_PARAM_COUNT) {
unsigned long value = 0;
switch(hvm_params[hvm_param_copy]) {
case HVM_PARAM_CONSOLE_PFN:
case HVM_PARAM_IOREQ_PFN:
case HVM_PARAM_BUFIOREQ_PFN:
case HVM_PARAM_STORE_PFN:
xc_get_hvm_param(xc, origin, hvm_params[hvm_param_copy], &value);
if (value) {
printf("Setting HVM param %i with value %lu\n",
hvm_params[hvm_param_copy], value);
xc_clear_domain_page(xc, clone, hvm_params[hvm_param_copy]);
xc_set_hvm_param(xc, clone, hvm_params[hvm_param_copy], value);
}
break;
}
hvm_param_copy++;
}*/
/*printf("Setting HVM context of clone\n");
if (xc_domain_hvm_setcontext(xc, clone, hvm_context, hvm_context_size)) {
printf("Failed to set HVM context.\n");
return 1;
}*/
xc_interface_close(xc);
return 0;
}
