[PATCH v1 2/7] s390x/mm: Implement arch_remove_memory()

David Hildenbrand
2019-04-24T10:25:06Z

Will come in handy when wanting to handle errors after
arch_add_memory().

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
arch/s390/mm/init.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 31b1071315d7..2636d62df04e 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -237,12 +237,13 @@ int arch_add_memory(int nid, u64 start, u64 size,
void arch_remove_memory(int nid, 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.
- */
- BUG();
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+ struct zone *zone;
+
+ vmem_remove_mapping(start, size);
+ zone = page_zone(pfn_to_page(start_pfn));
+ __remove_pages(zone, start_pfn, nr_pages, altmap);
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
--
2.20.1