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 }; 37 38 int arch_get_memory_phys_device(unsigned long start_pfn); 39 unsigned long memory_block_size_bytes(void); 40 41 /* These states are exposed to userspace as text strings in sysfs */ 42 #define MEM_ONLINE (1<<0) /* exposed to userspace */ 43 #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */ 44 #define MEM_OFFLINE (1<<2) /* exposed to userspace */ 45 #define MEM_GOING_ONLINE (1<<3) 46 #define MEM_CANCEL_ONLINE (1<<4) 47 #define MEM_CANCEL_OFFLINE (1<<5) 48 49 struct memory_notify { 50 unsigned long start_pfn; 51 unsigned long nr_pages; 52 int status_change_nid_normal; 53 int status_change_nid_high; 54 int status_change_nid; 55 }; 56 57 /* 58 * During pageblock isolation, count the number of pages within the 59 * range [start_pfn, start_pfn + nr_pages) which are owned by code 60 * in the notifier chain. 61 */ 62 #define MEM_ISOLATE_COUNT (1<<0) 63 64 struct memory_isolate_notify { 65 unsigned long start_pfn; /* Start of range to check */ 66 unsigned int nr_pages; /* # pages in range to check */ 67 unsigned int pages_found; /* # pages owned found by callbacks */ 68 }; 69 70 struct notifier_block; 71 struct mem_section; 72 73 /* 74 * Priorities for the hotplug memory callback routines (stored in decreasing 75 * order in the callback chain) 76 */ 77 #define SLAB_CALLBACK_PRI 1 78 #define IPC_CALLBACK_PRI 10 79 80 #ifndef CONFIG_MEMORY_HOTPLUG_SPARSE 81 static inline int memory_dev_init(void) 82 { 83 return 0; 84 } 85 static inline int register_memory_notifier(struct notifier_block *nb) 86 { 87 return 0; 88 } 89 static inline void unregister_memory_notifier(struct notifier_block *nb) 90 { 91 } 92 static inline int memory_notify(unsigned long val, void *v) 93 { 94 return 0; 95 } 96 static inline int register_memory_isolate_notifier(struct notifier_block *nb) 97 { 98 return 0; 99 } 100 static inline void unregister_memory_isolate_notifier(struct notifier_block *nb) 101 { 102 } 103 static inline int memory_isolate_notify(unsigned long val, void *v) 104 { 105 return 0; 106 } 107 #else 108 extern int register_memory_notifier(struct notifier_block *nb); 109 extern void unregister_memory_notifier(struct notifier_block *nb); 110 extern int register_memory_isolate_notifier(struct notifier_block *nb); 111 extern void unregister_memory_isolate_notifier(struct notifier_block *nb); 112 extern int register_new_memory(int, struct mem_section *); 113 #ifdef CONFIG_MEMORY_HOTREMOVE 114 extern int unregister_memory_section(struct mem_section *); 115 #endif 116 extern int memory_dev_init(void); 117 extern int memory_notify(unsigned long val, void *v); 118 extern int memory_isolate_notify(unsigned long val, void *v); 119 extern struct memory_block *find_memory_block_hinted(struct mem_section *, 120 struct memory_block *); 121 extern struct memory_block *find_memory_block(struct mem_section *); 122 #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT) 123 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 124 125 #ifdef CONFIG_MEMORY_HOTPLUG 126 #define hotplug_memory_notifier(fn, pri) ({ \ 127 static __meminitdata struct notifier_block fn##_mem_nb =\ 128 { .notifier_call = fn, .priority = pri };\ 129 register_memory_notifier(&fn##_mem_nb); \ 130 }) 131 #define register_hotmemory_notifier(nb) register_memory_notifier(nb) 132 #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) 133 #else 134 #define hotplug_memory_notifier(fn, pri) ({ 0; }) 135 /* These aren't inline functions due to a GCC bug. */ 136 #define register_hotmemory_notifier(nb) ({ (void)(nb); 0; }) 137 #define unregister_hotmemory_notifier(nb) ({ (void)(nb); }) 138 #endif 139 140 /* 141 * Kernel text modification mutex, used for code patching. Users of this lock 142 * can sleep. 143 */ 144 extern struct mutex text_mutex; 145 146 #endif /* _LINUX_MEMORY_H_ */ 147