diff options
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index a74c4e954352..eccdab4bb44a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -23,6 +23,7 @@ #include <linux/page_ext.h> #include <linux/err.h> #include <linux/page_ref.h> +#include <linux/memremap.h> struct mempolicy; struct anon_vma; @@ -792,25 +793,25 @@ static inline bool is_zone_device_page(const struct page *page) { return page_zonenum(page) == ZONE_DEVICE; } - -static inline bool is_device_private_page(const struct page *page) -{ - /* See MEMORY_DEVICE_PRIVATE in include/linux/memory_hotplug.h */ - return ((page_zonenum(page) == ZONE_DEVICE) && - (page->pgmap->type == MEMORY_DEVICE_PRIVATE)); -} #else static inline bool is_zone_device_page(const struct page *page) { return false; } +#endif -static inline bool is_device_private_page(const struct page *page) +#ifdef CONFIG_DEVICE_PRIVATE +void put_zone_device_private_page(struct page *page); +#else +static inline void put_zone_device_private_page(struct page *page) { - return false; } #endif +static inline bool is_device_private_page(const struct page *page); + +DECLARE_STATIC_KEY_FALSE(device_private_key); + static inline void get_page(struct page *page) { page = compound_head(page); @@ -826,6 +827,18 @@ static inline void put_page(struct page *page) { page = compound_head(page); + /* + * For private device pages we need to catch refcount transition from + * 2 to 1, when refcount reach one it means the private device page is + * free and we need to inform the device driver through callback. See + * include/linux/memremap.h and HMM for details. + */ + if (static_branch_unlikely(&device_private_key) && + unlikely(is_device_private_page(page))) { + put_zone_device_private_page(page); + return; + } + if (put_page_testzero(page)) __put_page(page); } |