/* We increase/decrease in batches which fit in a page */
static xen_pfn_t frame_list[PAGE_SIZE / sizeof(unsigned long)];
-static DEFINE_PER_CPU(struct page *, balloon_scratch_page);
/* List of ballooned pages, threaded through the mem_map array. */
page = pfn_to_page(pfn);
#ifdef CONFIG_XEN_HAVE_PVMMU
- /*
- * Ballooned out frames are effectively replaced with
- * a scratch frame. Ensure direct mappings and the
- * p2m are consistent.
- */
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
if (!PageHighMem(page)) {
- struct page *scratch_page = get_balloon_scratch_page();
-
ret = HYPERVISOR_update_va_mapping(
(unsigned long)__va(pfn << PAGE_SHIFT),
- pfn_pte(page_to_pfn(scratch_page),
- PAGE_KERNEL_RO), 0);
+ __pte_ma(0), 0);
BUG_ON(ret);
-
- put_balloon_scratch_page();
}
__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
}
mutex_unlock(&balloon_mutex);
}
-struct page *get_balloon_scratch_page(void)
-{
- struct page *ret = get_cpu_var(balloon_scratch_page);
- BUG_ON(ret == NULL);
- return ret;
-}
-
-void put_balloon_scratch_page(void)
-{
- put_cpu_var(balloon_scratch_page);
-}
-
/* Resets the Xen limit, sets new target, and kicks off processing. */
void balloon_set_new_target(unsigned long target)
{
}
}
-static int alloc_balloon_scratch_page(int cpu)
-{
- if (per_cpu(balloon_scratch_page, cpu) != NULL)
- return 0;
-
- per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL);
- if (per_cpu(balloon_scratch_page, cpu) == NULL) {
- pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu);
- return -ENOMEM;
- }
-
- return 0;
-}
-
-
-static int balloon_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- int cpu = (long)hcpu;
- switch (action) {
- case CPU_UP_PREPARE:
- if (alloc_balloon_scratch_page(cpu))
- return NOTIFY_BAD;
- break;
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block balloon_cpu_notifier = {
- .notifier_call = balloon_cpu_notify,
-};
-
static int __init balloon_init(void)
{
- int i, cpu;
+ int i;
if (!xen_domain())
return -ENODEV;
- if (!xen_feature(XENFEAT_auto_translated_physmap)) {
- register_cpu_notifier(&balloon_cpu_notifier);
-
- get_online_cpus();
- for_each_online_cpu(cpu) {
- if (alloc_balloon_scratch_page(cpu)) {
- put_online_cpus();
- unregister_cpu_notifier(&balloon_cpu_notifier);
- return -ENOMEM;
- }
- }
- put_online_cpus();
- }
-
pr_info("Initialising balloon driver\n");
balloon_stats.current_pages = xen_pv_domain()
subsys_initcall(balloon_init);
-static int __init balloon_clear(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu)
- per_cpu(balloon_scratch_page, cpu) = NULL;
-
- return 0;
-}
-early_initcall(balloon_clear);
-
MODULE_LICENSE("GPL");