include/linux/memory.h

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