diff options
Diffstat (limited to 'include/linux/page_ext.h')
-rw-r--r-- | include/linux/page_ext.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index 22be4582faae..67314f648aeb 100644 --- a/include/linux/page_ext.h +++ b/include/linux/page_ext.h @@ -7,15 +7,33 @@ #include <linux/stackdepot.h> struct pglist_data; + +/** + * struct page_ext_operations - per page_ext client operations + * @offset: Offset to the client's data within page_ext. Offset is returned to + * the client by page_ext_init. + * @size: The size of the client data within page_ext. + * @need: Function that returns true if client requires page_ext. + * @init: (optional) Called to initialize client once page_exts are allocated. + * @need_shared_flags: True when client is using shared page_ext->flags + * field. + * + * Each Page Extension client must define page_ext_operations in + * page_ext_ops array. + */ struct page_ext_operations { size_t offset; size_t size; bool (*need)(void); void (*init)(void); + bool need_shared_flags; }; #ifdef CONFIG_PAGE_EXTENSION +/* + * The page_ext_flags users must set need_shared_flags to true. + */ enum page_ext_flags { PAGE_EXT_OWNER, PAGE_EXT_OWNER_ALLOCATED, |