[RFC PATCH 2/5] mmzone: new pgdat flags for DRAM and PMEM

[Fan Du <fan.du@intel.com>]

One system with DRAM and PMEM, we need new flag
to tag pgdat is made of DRAM or peristent memory.

This patch serves as preparetion one for follow up patch.

Signed-off-by: Fan Du <fan.du@intel.com>
---
 include/linux/mmzone.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index fba7741..d3ee9f9 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -520,6 +520,8 @@ enum pgdat_flags {
 					 * many pages under writeback
 					 */
 	PGDAT_RECLAIM_LOCKED,		/* prevents concurrent reclaim */
+	PGDAT_DRAM,			/* Volatile DRAM memory node */
+	PGDAT_PMEM,			/* Persistent memory node */
 };
 
 enum zone_flags {
@@ -923,6 +925,30 @@ extern int numa_zonelist_order_handler(struct ctl_table *, int,
 
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 
+static inline int is_node_pmem(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	return test_bit(PGDAT_PMEM, &pgdat->flags);
+}
+
+static inline int is_node_dram(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	return test_bit(PGDAT_DRAM, &pgdat->flags);
+}
+
+static inline void set_node_type(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	if (node_isset(nid, numa_nodes_pmem))
+		set_bit(PGDAT_PMEM, &pgdat->flags);
+	else
+		set_bit(PGDAT_DRAM, &pgdat->flags);
+}
+
 extern struct pglist_data *first_online_pgdat(void);
 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
 extern struct zone *next_zone(struct zone *zone);
-- 
1.8.3.1