include/linux/node.h

   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 #include <linux/workqueue.h>
  22
  23 /**
  24  * struct node_hmem_attrs - heterogeneous memory performance attributes
  25  *
  26  * @read_bandwidth:     Read bandwidth in MB/s
  27  * @write_bandwidth:    Write bandwidth in MB/s
  28  * @read_latency:       Read latency in nanoseconds
  29  * @write_latency:      Write latency in nanoseconds
  30  */
  31 struct node_hmem_attrs {
  32         unsigned int read_bandwidth;
  33         unsigned int write_bandwidth;
  34         unsigned int read_latency;
  35         unsigned int write_latency;
  36 };
  37
  38 enum cache_indexing {
  39         NODE_CACHE_DIRECT_MAP,
  40         NODE_CACHE_INDEXED,
  41         NODE_CACHE_OTHER,
  42 };
  43
  44 enum cache_write_policy {
  45         NODE_CACHE_WRITE_BACK,
  46         NODE_CACHE_WRITE_THROUGH,
  47         NODE_CACHE_WRITE_OTHER,
  48 };
  49
  50 /**
  51  * struct node_cache_attrs - system memory caching attributes
  52  *
  53  * @indexing:           The ways memory blocks may be placed in cache
  54  * @write_policy:       Write back or write through policy
  55  * @size:               Total size of cache in bytes
  56  * @line_size:          Number of bytes fetched on a cache miss
  57  * @level:              The cache hierarchy level
  58  */
  59 struct node_cache_attrs {
  60         enum cache_indexing indexing;
  61         enum cache_write_policy write_policy;
  62         u64 size;
  63         u16 line_size;
  64         u8 level;
  65 };
  66
  67 #ifdef CONFIG_HMEM_REPORTING
  68 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
  69 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
  70                          unsigned access);
  71 #else
  72 static inline void node_add_cache(unsigned int nid,
  73                                   struct node_cache_attrs *cache_attrs)
  74 {
  75 }
  76
  77 static inline void node_set_perf_attrs(unsigned int nid,
  78                                        struct node_hmem_attrs *hmem_attrs,
  79                                        unsigned access)
  80 {
  81 }
  82 #endif
  83
  84 struct node {
  85         struct device   dev;
  86         struct list_head access_list;
  87
  88 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
  89         struct work_struct      node_work;
  90 #endif
  91 #ifdef CONFIG_HMEM_REPORTING
  92         struct list_head cache_attrs;
  93         struct device *cache_dev;
  94 #endif
  95 };
  96
  97 struct memory_block;
  98 extern struct node *node_devices[];
  99 typedef  void (*node_registration_func_t)(struct node *);
 100
 101 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
 102 void link_mem_sections(int nid, unsigned long start_pfn,
 103                        unsigned long end_pfn,
 104                        enum meminit_context context);
 105 #else
 106 static inline void link_mem_sections(int nid, unsigned long start_pfn,
 107                                      unsigned long end_pfn,
 108                                      enum meminit_context context)
 109 {
 110 }
 111 #endif
 112
 113 extern void unregister_node(struct node *node);
 114 #ifdef CONFIG_NUMA
 115 /* Core of the node registration - only memory hotplug should use this */
 116 extern int __register_one_node(int nid);
 117
 118 /* Registers an online node */
 119 static inline int register_one_node(int nid)
 120 {
 121         int error = 0;
 122
 123         if (node_online(nid)) {
 124                 struct pglist_data *pgdat = NODE_DATA(nid);
 125                 unsigned long start_pfn = pgdat->node_start_pfn;
 126                 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
 127
 128                 error = __register_one_node(nid);
 129                 if (error)
 130                         return error;
 131                 /* link memory sections under this node */
 132                 link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY);
 133         }
 134
 135         return error;
 136 }
 137
 138 extern void unregister_one_node(int nid);
 139 extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
 140 extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
 141 extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
 142
 143 extern int register_memory_node_under_compute_node(unsigned int mem_nid,
 144                                                    unsigned int cpu_nid,
 145                                                    unsigned access);
 146
 147 #ifdef CONFIG_HUGETLBFS
 148 extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
 149                                          node_registration_func_t unregister);
 150 #endif
 151 #else
 152 static inline int __register_one_node(int nid)
 153 {
 154         return 0;
 155 }
 156 static inline int register_one_node(int nid)
 157 {
 158         return 0;
 159 }
 160 static inline int unregister_one_node(int nid)
 161 {
 162         return 0;
 163 }
 164 static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
 165 {
 166         return 0;
 167 }
 168 static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 169 {
 170         return 0;
 171 }
 172 static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 173 {
 174 }
 175
 176 static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
 177                                                 node_registration_func_t unreg)
 178 {
 179 }
 180 #endif
 181
 182 #define to_node(device) container_of(device, struct node, dev)
 183
 184 #endif /* _LINUX_NODE_H_ */