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/list.h>
21
22/**
23 * struct node_hmem_attrs - heterogeneous memory performance attributes
24 *
25 * @read_bandwidth: Read bandwidth in MB/s
26 * @write_bandwidth: Write bandwidth in MB/s
27 * @read_latency: Read latency in nanoseconds
28 * @write_latency: Write latency in nanoseconds
29 */
30struct node_hmem_attrs {
31 unsigned int read_bandwidth;
32 unsigned int write_bandwidth;
33 unsigned int read_latency;
34 unsigned int write_latency;
35};
36
37enum cache_indexing {
38 NODE_CACHE_DIRECT_MAP,
39 NODE_CACHE_INDEXED,
40 NODE_CACHE_OTHER,
41};
42
43enum cache_write_policy {
44 NODE_CACHE_WRITE_BACK,
45 NODE_CACHE_WRITE_THROUGH,
46 NODE_CACHE_WRITE_OTHER,
47};
48
49/**
50 * struct node_cache_attrs - system memory caching attributes
51 *
52 * @indexing: The ways memory blocks may be placed in cache
53 * @write_policy: Write back or write through policy
54 * @size: Total size of cache in bytes
55 * @line_size: Number of bytes fetched on a cache miss
56 * @level: The cache hierarchy level
57 */
58struct node_cache_attrs {
59 enum cache_indexing indexing;
60 enum cache_write_policy write_policy;
61 u64 size;
62 u16 line_size;
63 u8 level;
64};
65
66#ifdef CONFIG_HMEM_REPORTING
67void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
68void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
69 unsigned access);
70#else
71static inline void node_add_cache(unsigned int nid,
72 struct node_cache_attrs *cache_attrs)
73{
74}
75
76static inline void node_set_perf_attrs(unsigned int nid,
77 struct node_hmem_attrs *hmem_attrs,
78 unsigned access)
79{
80}
81#endif
82
83struct node {
84 struct device dev;
85 struct list_head access_list;
86#ifdef CONFIG_HMEM_REPORTING
87 struct list_head cache_attrs;
88 struct device *cache_dev;
89#endif
90};
91
92struct memory_block;
93extern struct node *node_devices[];
94
95#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA)
96void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
97 unsigned long end_pfn,
98 enum meminit_context context);
99#else
100static inline void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
101 unsigned long end_pfn,
102 enum meminit_context context)
103{
104}
105#endif
106
107extern void unregister_node(struct node *node);
108#ifdef CONFIG_NUMA
109extern void node_dev_init(void);
110/* Core of the node registration - only memory hotplug should use this */
111extern int __register_one_node(int nid);
112
113/* Registers an online node */
114static inline int register_one_node(int nid)
115{
116 int error = 0;
117
118 if (node_online(nid)) {
119 struct pglist_data *pgdat = NODE_DATA(nid);
120 unsigned long start_pfn = pgdat->node_start_pfn;
121 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
122
123 error = __register_one_node(nid);
124 if (error)
125 return error;
126 register_memory_blocks_under_node(nid, start_pfn, end_pfn,
127 MEMINIT_EARLY);
128 }
129
130 return error;
131}
132
133extern void unregister_one_node(int nid);
134extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
135extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
136extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
137
138extern int register_memory_node_under_compute_node(unsigned int mem_nid,
139 unsigned int cpu_nid,
140 unsigned access);
141#else
142static inline void node_dev_init(void)
143{
144}
145static inline int __register_one_node(int nid)
146{
147 return 0;
148}
149static inline int register_one_node(int nid)
150{
151 return 0;
152}
153static inline int unregister_one_node(int nid)
154{
155 return 0;
156}
157static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
158{
159 return 0;
160}
161static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
162{
163 return 0;
164}
165static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
166{
167}
168#endif
169
170#define to_node(device) container_of(device, struct node, dev)
171
172#endif /* _LINUX_NODE_H_ */
173

source code of linux/include/linux/node.h