LXR linux/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
  25struct 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
  37int arch_get_memory_phys_device(unsigned long start_pfn);
  38
  39/* These states are exposed to userspace as text strings in sysfs */
  40#define MEM_ONLINE              (1<<0) /* exposed to userspace */
  41#define MEM_GOING_OFFLINE       (1<<1) /* exposed to userspace */
  42#define MEM_OFFLINE             (1<<2) /* exposed to userspace */
  43#define MEM_GOING_ONLINE        (1<<3)
  44#define MEM_CANCEL_ONLINE       (1<<4)
  45#define MEM_CANCEL_OFFLINE      (1<<5)
  46
  47struct memory_notify {
  48        unsigned long start_pfn;
  49        unsigned long nr_pages;
  50        int status_change_nid_normal;
  51        int status_change_nid_high;
  52        int status_change_nid;
  53};
  54
  55/*
  56 * During pageblock isolation, count the number of pages within the
  57 * range [start_pfn, start_pfn + nr_pages) which are owned by code
  58 * in the notifier chain.
  59 */
  60#define MEM_ISOLATE_COUNT       (1<<0)
  61
  62struct memory_isolate_notify {
  63        unsigned long start_pfn;        /* Start of range to check */
  64        unsigned int nr_pages;          /* # pages in range to check */
  65        unsigned int pages_found;       /* # pages owned found by callbacks */
  66};
  67
  68struct notifier_block;
  69struct mem_section;
  70
  71/*
  72 * Priorities for the hotplug memory callback routines (stored in decreasing
  73 * order in the callback chain)
  74 */
  75#define SLAB_CALLBACK_PRI       1
  76#define IPC_CALLBACK_PRI        10
  77
  78#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
  79static inline int memory_dev_init(void)
  80{
  81        return 0;
  82}
  83static inline int register_memory_notifier(struct notifier_block *nb)
  84{
  85        return 0;
  86}
  87static inline void unregister_memory_notifier(struct notifier_block *nb)
  88{
  89}
  90static inline int memory_notify(unsigned long val, void *v)
  91{
  92        return 0;
  93}
  94static inline int register_memory_isolate_notifier(struct notifier_block *nb)
  95{
  96        return 0;
  97}
  98static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
  99{
 100}
 101static inline int memory_isolate_notify(unsigned long val, void *v)
 102{
 103        return 0;
 104}
 105#else
 106extern int register_memory_notifier(struct notifier_block *nb);
 107extern void unregister_memory_notifier(struct notifier_block *nb);
 108extern int register_memory_isolate_notifier(struct notifier_block *nb);
 109extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
 110extern int register_new_memory(int, struct mem_section *);
 111#ifdef CONFIG_MEMORY_HOTREMOVE
 112extern int unregister_memory_section(struct mem_section *);
 113#endif
 114extern int memory_dev_init(void);
 115extern int memory_notify(unsigned long val, void *v);
 116extern int memory_isolate_notify(unsigned long val, void *v);
 117extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 118                                                        struct memory_block *);
 119extern struct memory_block *find_memory_block(struct mem_section *);
 120#define CONFIG_MEM_BLOCK_SIZE   (PAGES_PER_SECTION<<PAGE_SHIFT)
 121#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 122
 123#ifdef CONFIG_MEMORY_HOTPLUG
 124#define hotplug_memory_notifier(fn, pri) ({             \
 125        static __meminitdata struct notifier_block fn##_mem_nb =\
 126                { .notifier_call = fn, .priority = pri };\
 127        register_memory_notifier(&fn##_mem_nb);                 \
 128})
 129#define register_hotmemory_notifier(nb)         register_memory_notifier(nb)
 130#define unregister_hotmemory_notifier(nb)       unregister_memory_notifier(nb)
 131#else
 132#define hotplug_memory_notifier(fn, pri)        ({ 0; })
 133/* These aren't inline functions due to a GCC bug. */
 134#define register_hotmemory_notifier(nb)    ({ (void)(nb); 0; })
 135#define unregister_hotmemory_notifier(nb)  ({ (void)(nb); })
 136#endif
 137
 138/*
 139 * 'struct memory_accessor' is a generic interface to provide
 140 * in-kernel access to persistent memory such as i2c or SPI EEPROMs
 141 */
 142struct memory_accessor {
 143        ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
 144                        size_t count);
 145        ssize_t (*write)(struct memory_accessor *, const char *buf,
 146                         off_t offset, size_t count);
 147};
 148
 149/*
 150 * Kernel text modification mutex, used for code patching. Users of this lock
 151 * can sleep.
 152 */
 153extern struct mutex text_mutex;
 154
 155#endif /* _LINUX_MEMORY_H_ */
 156