mm/memory_hotplug: prepare passing flags to add_memory() and friends

We soon want to pass flags, e.g., to mark added System RAM resources.
mergeable.  Prepare for that.

This patch is based on a similar patch by Oscar Salvador:

https://lkml.kernel.org/r/[email protected]

Signed-off-by: David Hildenbrand <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Juergen Gross <[email protected]> # Xen related part
Reviewed-by: Pankaj Gupta <[email protected]>
Acked-by: Wei Liu <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Vishal Verma <[email protected]>
Cc: Dave Jiang <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Wei Liu <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Stefano Stabellini <[email protected]>
Cc: "Oliver O'Halloran" <[email protected]>
Cc: Pingfan Liu <[email protected]>
Cc: Nathan Lynch <[email protected]>
Cc: Libor Pechacek <[email protected]>
Cc: Anton Blanchard <[email protected]>
Cc: Leonardo Bras <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: Julien Grall <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Roger Pau Monné <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Wei Yang <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 12 insertions, 4 deletions

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 1504b4d5ae6c..33eb80fdba22 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -57,6 +57,12 @@ enum {
 	MMOP_ONLINE_MOVABLE,
 };
 
+/* Flags for add_memory() and friends to specify memory hotplug details. */
+typedef int __bitwise mhp_t;
+
+/* No special request */
+#define MHP_NONE		((__force mhp_t)0)
+
 /*
  * Extended parameters for memory hotplug:
  * altmap: alternative allocator for memmap array (optional)
@@ -339,11 +345,13 @@ extern void clear_zone_contiguous(struct zone *zone);
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 extern void __ref free_area_init_core_hotplug(int nid);
-extern int __add_memory(int nid, u64 start, u64 size);
-extern int add_memory(int nid, u64 start, u64 size);
-extern int add_memory_resource(int nid, struct resource *resource);
+extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
+extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
+extern int add_memory_resource(int nid, struct resource *resource,
+			       mhp_t mhp_flags);
 extern int add_memory_driver_managed(int nid, u64 start, u64 size,
-				     const char *resource_name);
+				     const char *resource_name,
+				     mhp_t mhp_flags);
 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 				   unsigned long nr_pages,
 				   struct vmem_altmap *altmap, int migratetype);