mm/memcg: Add folio_memcg_lock() and folio_memcg_unlock()

These are the folio equivalents of lock_page_memcg() and
unlock_page_memcg().

lock_page_memcg() and unlock_page_memcg() have too many callers to be
easily replaced in a single patch, so reimplement them as wrappers for
now to be cleaned up later when enough callers have been converted to
use folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 1c2776c3a223..be85450f066f 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -978,6 +978,8 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg);
 extern bool cgroup_memory_noswap;
 #endif
 
+void folio_memcg_lock(struct folio *folio);
+void folio_memcg_unlock(struct folio *folio);
 void lock_page_memcg(struct page *page);
 void unlock_page_memcg(struct page *page);
 
@@ -1397,6 +1399,14 @@ static inline void unlock_page_memcg(struct page *page)
 {
 }
 
+static inline void folio_memcg_lock(struct folio *folio)
+{
+}
+
+static inline void folio_memcg_unlock(struct folio *folio)
+{
+}
+
 static inline void mem_cgroup_handle_over_high(void)
 {
 }