60 lines
1.6 KiB
C
60 lines
1.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/mm.h>
|
|
#include <linux/page-isolation.h>
|
|
|
|
unsigned int _debug_guardpage_minorder;
|
|
|
|
bool _debug_pagealloc_enabled_early __read_mostly
|
|
= IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT);
|
|
EXPORT_SYMBOL(_debug_pagealloc_enabled_early);
|
|
DEFINE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
|
|
EXPORT_SYMBOL(_debug_pagealloc_enabled);
|
|
|
|
DEFINE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
|
|
|
|
static int __init early_debug_pagealloc(char *buf)
|
|
{
|
|
return kstrtobool(buf, &_debug_pagealloc_enabled_early);
|
|
}
|
|
early_param("debug_pagealloc", early_debug_pagealloc);
|
|
|
|
static int __init debug_guardpage_minorder_setup(char *buf)
|
|
{
|
|
unsigned long res;
|
|
|
|
if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) {
|
|
pr_err("Bad debug_guardpage_minorder value\n");
|
|
return 0;
|
|
}
|
|
_debug_guardpage_minorder = res;
|
|
pr_info("Setting debug_guardpage_minorder to %lu\n", res);
|
|
return 0;
|
|
}
|
|
early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
|
|
|
|
bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order,
|
|
int migratetype)
|
|
{
|
|
if (order >= debug_guardpage_minorder())
|
|
return false;
|
|
|
|
__SetPageGuard(page);
|
|
INIT_LIST_HEAD(&page->buddy_list);
|
|
set_page_private(page, order);
|
|
/* Guard pages are not available for any usage */
|
|
if (!is_migrate_isolate(migratetype))
|
|
__mod_zone_freepage_state(zone, -(1 << order), migratetype);
|
|
|
|
return true;
|
|
}
|
|
|
|
void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order,
|
|
int migratetype)
|
|
{
|
|
__ClearPageGuard(page);
|
|
|
|
set_page_private(page, 0);
|
|
if (!is_migrate_isolate(migratetype))
|
|
__mod_zone_freepage_state(zone, (1 << order), migratetype);
|
|
}
|