diff options
Diffstat (limited to 'include/linux/memory_hotplug.h')
| -rw-r--r-- | include/linux/memory_hotplug.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 3c8cf86201c3..a61aede1b391 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -14,6 +14,20 @@ struct memory_block; struct resource; #ifdef CONFIG_MEMORY_HOTPLUG +/* + * Return page for the valid pfn only if the page is online. All pfn + * walkers which rely on the fully initialized page->flags and others + * should use this rather than pfn_valid && pfn_to_page + */ +#define pfn_to_online_page(pfn) \ +({ \ + struct page *___page = NULL; \ + unsigned long ___nr = pfn_to_section_nr(pfn); \ + \ + if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr))\ + ___page = pfn_to_page(pfn); \ + ___page; \ +}) /* * Types for free bootmem stored in page->lru.next. These have to be in @@ -203,6 +217,14 @@ extern void set_zone_contiguous(struct zone *zone); extern void clear_zone_contiguous(struct zone *zone); #else /* ! CONFIG_MEMORY_HOTPLUG */ +#define pfn_to_online_page(pfn) \ +({ \ + struct page *___page = NULL; \ + if (pfn_valid(pfn)) \ + ___page = pfn_to_page(pfn); \ + ___page; \ + }) + /* * Stub functions for when hotplug is off */ |