mm/page_poison: expose page_poisoning_enabled to kernel modules

In some usages, e.g. virtio-balloon, a kernel module needs to know if
page poisoning is in use. This patch exposes the page_poisoning_enabled
function to kernel modules.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Wei Wang 2018-08-27 09:32:18 +08:00 committed by Michael S. Tsirkin
parent 86a559787e
commit d95f58f4a6

View File

@ -17,6 +17,11 @@ static int __init early_page_poison_param(char *buf)
}
early_param("page_poison", early_page_poison_param);
/**
* page_poisoning_enabled - check if page poisoning is enabled
*
* Return true if page poisoning is enabled, or false if not.
*/
bool page_poisoning_enabled(void)
{
/*
@ -29,6 +34,7 @@ bool page_poisoning_enabled(void)
(!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
debug_pagealloc_enabled()));
}
EXPORT_SYMBOL_GPL(page_poisoning_enabled);
static void poison_page(struct page *page)
{