root/include/linux/memory.h

INCLUDED FROM

DEFINITIONS

1. memory_dev_init
2. register_memory_notifier
3. unregister_memory_notifier
4. memory_notify
5. register_memory_isolate_notifier
6. unregister_memory_isolate_notifier
7. memory_isolate_notify

   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_ */