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 state; /* serialized by the dev->lock */ 29 int section_count; /* serialized by mem_sysfs_mutex */ 30 int online_type; /* for passing data to online routine */ 31 int phys_device; /* to which fru does this belong? */ 32 void *hw; /* optional pointer to fw/hw data */ 33 int (*phys_callback)(struct memory_block *); 34 struct device dev; 35 int nid; /* NID for this memory block */ 36 }; 37 38 int arch_get_memory_phys_device(unsigned long start_pfn); 39 unsigned long memory_block_size_bytes(void); 40 int set_memory_block_size_order(unsigned int order); 41 42 /* These states are exposed to userspace as text strings in sysfs */ 43 #define MEM_ONLINE (1<<0) /* exposed to userspace */ 44 #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */ 45 #define MEM_OFFLINE (1<<2) /* exposed to userspace */ 46 #define MEM_GOING_ONLINE (1<<3) 47 #define MEM_CANCEL_ONLINE (1<<4) 48 #define MEM_CANCEL_OFFLINE (1<<5) 49 50 struct memory_notify { 51 unsigned long start_pfn; 52 unsigned long nr_pages; 53 int status_change_nid_normal; 54 int status_change_nid_high; 55 int status_change_nid; 56 }; 57 58 /* 59 * During pageblock isolation, count the number of pages within the 60 * range [start_pfn, start_pfn + nr_pages) which are owned by code 61 * in the notifier chain. 62 */ 63 #define MEM_ISOLATE_COUNT (1<<0) 64 65 struct memory_isolate_notify { 66 unsigned long start_pfn; /* Start of range to check */ 67 unsigned int nr_pages; /* # pages in range to check */ 68 unsigned int pages_found; /* # pages owned found by callbacks */ 69 }; 70 71 struct notifier_block; 72 struct mem_section; 73 74 /* 75 * Priorities for the hotplug memory callback routines (stored in decreasing 76 * order in the callback chain) 77 */ 78 #define SLAB_CALLBACK_PRI 1 79 #define IPC_CALLBACK_PRI 10 80 81 #ifndef CONFIG_MEMORY_HOTPLUG_SPARSE 82 static inline void memory_dev_init(void) 83 { 84 return; 85 } 86 static inline int register_memory_notifier(struct notifier_block *nb) 87 { 88 return 0; 89 } 90 static inline void unregister_memory_notifier(struct notifier_block *nb) 91 { 92 } 93 static inline int memory_notify(unsigned long val, void *v) 94 { 95 return 0; 96 } 97 static inline int register_memory_isolate_notifier(struct notifier_block *nb) 98 { 99 return 0; 100 } 101 static inline void unregister_memory_isolate_notifier(struct notifier_block *nb) 102 { 103 } 104 static inline int memory_isolate_notify(unsigned long val, void *v) 105 { 106 return 0; 107 } 108 #else 109 extern int register_memory_notifier(struct notifier_block *nb); 110 extern void unregister_memory_notifier(struct notifier_block *nb); 111 extern int register_memory_isolate_notifier(struct notifier_block *nb); 112 extern void unregister_memory_isolate_notifier(struct notifier_block *nb); 113 int create_memory_block_devices(unsigned long start, unsigned long size); 114 void remove_memory_block_devices(unsigned long start, unsigned long size); 115 extern void memory_dev_init(void); 116 extern int memory_notify(unsigned long val, void *v); 117 extern int memory_isolate_notify(unsigned long val, void *v); 118 extern struct memory_block *find_memory_block(struct mem_section *); 119 typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *); 120 extern int walk_memory_blocks(unsigned long start, unsigned long size, 121 void *arg, walk_memory_blocks_func_t func); 122 extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func); 123 #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT) 124 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 125 126 #ifdef CONFIG_MEMORY_HOTPLUG 127 #define hotplug_memory_notifier(fn, pri) ({ \ 128 static __meminitdata struct notifier_block fn##_mem_nb =\ 129 { .notifier_call = fn, .priority = pri };\ 130 register_memory_notifier(&fn##_mem_nb); \ 131 }) 132 #define register_hotmemory_notifier(nb) register_memory_notifier(nb) 133 #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) 134 #else 135 #define hotplug_memory_notifier(fn, pri) ({ 0; }) 136 /* These aren't inline functions due to a GCC bug. */ 137 #define register_hotmemory_notifier(nb) ({ (void)(nb); 0; }) 138 #define unregister_hotmemory_notifier(nb) ({ (void)(nb); }) 139 #endif 140 141 /* 142 * Kernel text modification mutex, used for code patching. Users of this lock 143 * can sleep. 144 */ 145 extern struct mutex text_mutex; 146 147 #endif /* _LINUX_MEMORY_H_ */ 148