diff options
Diffstat (limited to 'include/linux/mm_types.h')
| -rw-r--r-- | include/linux/mm_types.h | 25 |
1 files changed, 10 insertions, 15 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index bcc5ee8b7b07..0b0c0e224011 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -113,7 +113,13 @@ struct page { }; }; - union { + union { /* This union is 4 bytes in size. */ + /* + * If the page can be mapped to userspace, encodes the number + * of times this page is referenced by a page table. + */ + atomic_t _mapcount; + /* * If the page is neither PageSlab nor mappable to userspace, * the value stored here may help determine what this page @@ -124,22 +130,11 @@ struct page { unsigned int active; /* SLAB */ int units; /* SLOB */ - - struct { /* Page cache */ - /* - * Count of ptes mapped in mms, to show when - * page is mapped & limit reverse map searches. - */ - atomic_t _mapcount; - - /* - * Usage count, *USE WRAPPER FUNCTION* when manual - * accounting. See page_ref.h - */ - atomic_t _refcount; - }; }; + /* Usage count. *DO NOT USE DIRECTLY*. See page_ref.h */ + atomic_t _refcount; + /* * WARNING: bit 0 of the first word encode PageTail(). That means * the rest users of the storage space MUST NOT use the bit to |