With virtio-mem, we actually want to remove memory again.
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: linux-s390@xxxxxxxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
arch/s390/mm/init.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 3fa3e5323612..7202344d0eae 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -242,12 +242,18 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
#ifdef CONFIG_MEMORY_HOTREMOVE
int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
{
- /*
- * There is no hardware or firmware interface which could trigger a
- * hot memory remove on s390. So there is nothing that needs to be
- * implemented.
- */
- return -EBUSY;
+ const unsigned long start_pfn = start >> PAGE_SHIFT;
+ const unsigned long nr_pages = size >> PAGE_SHIFT;
+ struct page *page = pfn_to_page(start_pfn);
+ struct zone *zone;
+ int ret;
+
+ zone = page_zone(page);
+ ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
+ WARN_ON_ONCE(ret);
+ vmem_remove_mapping(start, size);
+
+ return ret;
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--
2.17.0
