1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * include/linux/memory.h - generic memory definition 4 * 5 * This is mainly for topological representation. We define the 6 * basic "struct memory_block" here, which can be embedded in per-arch 7 * definitions or NUMA information. 8 * 9 * Basic handling of the devices is done in drivers/base/memory.c 10 * and system devices are handled in drivers/base/sys.c. 11 * 12 * Memory block are exported via sysfs in the class/memory/devices/ 13 * directory. 14 * 15 */ 16 #ifndef _LINUX_MEMORY_H_ 17 #define _LINUX_MEMORY_H_ 18 19 #include <linux/node.h> 20 #include <linux/compiler.h> 21 #include <linux/mutex.h> 22 #include <linux/notifier.h> 23 24 #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) 25 26 struct memory_block { 27 unsigned long start_section_nr; 28 unsigned long end_section_nr; 29 unsigned long state; /* serialized by the dev->lock */ 30 int section_count; /* serialized by mem_sysfs_mutex */ 31 int online_type; /* for passing data to online routine */ 32 int phys_device; /* to which fru does this belong? */ 33 void *hw; /* optional pointer to fw/hw data */ 34 int (*phys_callback)(struct memory_block *); 35 struct device dev; 36 int nid; /* NID for this memory block */ 37 }; 38 39 int arch_get_memory_phys_device(unsigned long start_pfn); 40 unsigned long memory_block_size_bytes(void); 41 int set_memory_block_size_order(unsigned int order); 42 43 /* These states are exposed to userspace as text strings in sysfs */ 44 #define MEM_ONLINE (1<<0) /* exposed to userspace */ 45 #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */ 46 #define MEM_OFFLINE (1<<2) /* exposed to userspace */ 47 #define MEM_GOING_ONLINE (1<<3) 48 #define MEM_CANCEL_ONLINE (1<<4) 49 #define MEM_CANCEL_OFFLINE (1<<5) 50 51 struct memory_notify { 52 unsigned long start_pfn; 53 unsigned long nr_pages; 54 int status_change_nid_normal; 55 int status_change_nid_high; 56 int status_change_nid; 57 }; 58 59 /* 60 * During pageblock isolation, count the number of pages within the 61 * range [start_pfn, start_pfn + nr_pages) which are owned by code 62 * in the notifier chain. 63 */ 64 #define MEM_ISOLATE_COUNT (1<<0) 65 66 struct memory_isolate_notify { 67 unsigned long start_pfn; /* Start of range to check */ 68 unsigned int nr_pages; /* # pages in range to check */ 69 unsigned int pages_found; /* # pages owned found by callbacks */ 70 }; 71 72 struct notifier_block; 73 struct mem_section; 74 75 /* 76 * Priorities for the hotplug memory callback routines (stored in decreasing 77 * order in the callback chain) 78 */ 79 #define SLAB_CALLBACK_PRI 1 80 #define IPC_CALLBACK_PRI 10 81 82 #ifndef CONFIG_MEMORY_HOTPLUG_SPARSE 83 static inline int memory_dev_init(void) 84 { 85 return 0; 86 } 87 static inline int register_memory_notifier(struct notifier_block *nb) 88 { 89 return 0; 90 } 91 static inline void unregister_memory_notifier(struct notifier_block *nb) 92 { 93 } 94 static inline int memory_notify(unsigned long val, void *v) 95 { 96 return 0; 97 } 98 static inline int register_memory_isolate_notifier(struct notifier_block *nb) 99 { 100 return 0; 101 } 102 static inline void unregister_memory_isolate_notifier(struct notifier_block *nb) 103 { 104 } 105 static inline int memory_isolate_notify(unsigned long val, void *v) 106 { 107 return 0; 108 } 109 #else 110 extern int register_memory_notifier(struct notifier_block *nb); 111 extern void unregister_memory_notifier(struct notifier_block *nb); 112 extern int register_memory_isolate_notifier(struct notifier_block *nb); 113 extern void unregister_memory_isolate_notifier(struct notifier_block *nb); 114 int hotplug_memory_register(int nid, struct mem_section *section); 115 #ifdef CONFIG_MEMORY_HOTREMOVE 116 extern void unregister_memory_section(struct mem_section *); 117 #endif 118 extern int memory_dev_init(void); 119 extern int memory_notify(unsigned long val, void *v); 120 extern int memory_isolate_notify(unsigned long val, void *v); 121 extern struct memory_block *find_memory_block_hinted(struct mem_section *, 122 struct memory_block *); 123 extern struct memory_block *find_memory_block(struct mem_section *); 124 #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT) 125 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 126 127 #ifdef CONFIG_MEMORY_HOTPLUG 128 #define hotplug_memory_notifier(fn, pri) ({ \ 129 static __meminitdata struct notifier_block fn##_mem_nb =\ 130 { .notifier_call = fn, .priority = pri };\ 131 register_memory_notifier(&fn##_mem_nb); \ 132 }) 133 #define register_hotmemory_notifier(nb) register_memory_notifier(nb) 134 #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) 135 #else 136 #define hotplug_memory_notifier(fn, pri) ({ 0; }) 137 /* These aren't inline functions due to a GCC bug. */ 138 #define register_hotmemory_notifier(nb) ({ (void)(nb); 0; }) 139 #define unregister_hotmemory_notifier(nb) ({ (void)(nb); }) 140 #endif 141 142 /* 143 * Kernel text modification mutex, used for code patching. Users of this lock 144 * can sleep. 145 */ 146 extern struct mutex text_mutex; 147 148 #endif /* _LINUX_MEMORY_H_ */ 149