xref: /linux-6.15/include/linux/node.h (revision 7170e604)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * include/linux/node.h - generic node definition
4  *
5  * This is mainly for topological representation. We define the
6  * basic 'struct node' here, which can be embedded in per-arch
7  * definitions of processors.
8  *
9  * Basic handling of the devices is done in drivers/base/node.c
10  * and system devices are handled in drivers/base/sys.c.
11  *
12  * Nodes are exported via driverfs in the class/node/devices/
13  * directory.
14  */
15 #ifndef _LINUX_NODE_H_
16 #define _LINUX_NODE_H_
17 
18 #include <linux/device.h>
19 #include <linux/cpumask.h>
20 #include <linux/workqueue.h>
21 
22 struct node {
23 	struct device	dev;
24 
25 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
26 	struct work_struct	node_work;
27 #endif
28 };
29 
30 struct memory_block;
31 extern struct node *node_devices[];
32 typedef  void (*node_registration_func_t)(struct node *);
33 
34 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
35 extern int link_mem_sections(int nid, unsigned long start_pfn,
36 			     unsigned long nr_pages, bool check_nid);
37 #else
38 static inline int link_mem_sections(int nid, unsigned long start_pfn,
39 				    unsigned long nr_pages, bool check_nid)
40 {
41 	return 0;
42 }
43 #endif
44 
45 extern void unregister_node(struct node *node);
46 #ifdef CONFIG_NUMA
47 /* Core of the node registration - only memory hotplug should use this */
48 extern int __register_one_node(int nid);
49 
50 /* Registers an online node */
51 static inline int register_one_node(int nid)
52 {
53 	int error = 0;
54 
55 	if (node_online(nid)) {
56 		struct pglist_data *pgdat = NODE_DATA(nid);
57 
58 		error = __register_one_node(nid);
59 		if (error)
60 			return error;
61 		/* link memory sections under this node */
62 		error = link_mem_sections(nid, pgdat->node_start_pfn, pgdat->node_spanned_pages, true);
63 	}
64 
65 	return error;
66 }
67 
68 extern void unregister_one_node(int nid);
69 extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
70 extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
71 extern int register_mem_sect_under_node(struct memory_block *mem_blk,
72 						int nid, bool check_nid);
73 extern int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
74 					   unsigned long phys_index);
75 
76 #ifdef CONFIG_HUGETLBFS
77 extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
78 					 node_registration_func_t unregister);
79 #endif
80 #else
81 static inline int __register_one_node(int nid)
82 {
83 	return 0;
84 }
85 static inline int register_one_node(int nid)
86 {
87 	return 0;
88 }
89 static inline int unregister_one_node(int nid)
90 {
91 	return 0;
92 }
93 static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
94 {
95 	return 0;
96 }
97 static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
98 {
99 	return 0;
100 }
101 static inline int register_mem_sect_under_node(struct memory_block *mem_blk,
102 							int nid, bool check_nid)
103 {
104 	return 0;
105 }
106 static inline int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
107 						  unsigned long phys_index)
108 {
109 	return 0;
110 }
111 
112 static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
113 						node_registration_func_t unreg)
114 {
115 }
116 #endif
117 
118 #define to_node(device) container_of(device, struct node, dev)
119 
120 #endif /* _LINUX_NODE_H_ */
121