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/sysdev.h>
  19#include <linux/node.h>
  20#include <linux/compiler.h>
  21#include <linux/mutex.h>
  22
  23#define MIN_MEMORY_BLOCK_SIZE     (1 << SECTION_SIZE_BITS)
  24
  25struct memory_block {
  26        unsigned long start_section_nr;
  27        unsigned long end_section_nr;
  28        unsigned long state;
  29        int section_count;
  30
  31        /*
  32         * This serializes all state change requests.  It isn't
  33         * held during creation because the control files are
  34         * created long after the critical areas during
  35         * initialization.
  36         */
  37        struct mutex state_mutex;
  38        int phys_device;                /* to which fru does this belong? */
  39        void *hw;                       /* optional pointer to fw/hw data */
  40        int (*phys_callback)(struct memory_block *);
  41        struct sys_device sysdev;
  42};
  43
  44int arch_get_memory_phys_device(unsigned long start_pfn);
  45
  46/* These states are exposed to userspace as text strings in sysfs */
  47#define MEM_ONLINE              (1<<0) /* exposed to userspace */
  48#define MEM_GOING_OFFLINE       (1<<1) /* exposed to userspace */
  49#define MEM_OFFLINE             (1<<2) /* exposed to userspace */
  50#define MEM_GOING_ONLINE        (1<<3)
  51#define MEM_CANCEL_ONLINE       (1<<4)
  52#define MEM_CANCEL_OFFLINE      (1<<5)
  53
  54struct memory_notify {
  55        unsigned long start_pfn;
  56        unsigned long nr_pages;
  57        int status_change_nid;
  58};
  59
  60/*
  61 * During pageblock isolation, count the number of pages within the
  62 * range [start_pfn, start_pfn + nr_pages) which are owned by code
  63 * in the notifier chain.
  64 */
  65#define MEM_ISOLATE_COUNT       (1<<0)
  66
  67struct memory_isolate_notify {
  68        unsigned long start_pfn;        /* Start of range to check */
  69        unsigned int nr_pages;          /* # pages in range to check */
  70        unsigned int pages_found;       /* # pages owned found by callbacks */
  71};
  72
  73struct notifier_block;
  74struct mem_section;
  75
  76/*
  77 * Priorities for the hotplug memory callback routines (stored in decreasing
  78 * order in the callback chain)
  79 */
  80#define SLAB_CALLBACK_PRI       1
  81#define IPC_CALLBACK_PRI        10
  82
  83#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
  84static inline int memory_dev_init(void)
  85{
  86        return 0;
  87}
  88static inline int register_memory_notifier(struct notifier_block *nb)
  89{
  90        return 0;
  91}
  92static inline void unregister_memory_notifier(struct notifier_block *nb)
  93{
  94}
  95static inline int memory_notify(unsigned long val, void *v)
  96{
  97        return 0;
  98}
  99static inline int register_memory_isolate_notifier(struct notifier_block *nb)
 100{
 101        return 0;
 102}
 103static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
 104{
 105}
 106static inline int memory_isolate_notify(unsigned long val, void *v)
 107{
 108        return 0;
 109}
 110#else
 111extern int register_memory_notifier(struct notifier_block *nb);
 112extern void unregister_memory_notifier(struct notifier_block *nb);
 113extern int register_memory_isolate_notifier(struct notifier_block *nb);
 114extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
 115extern int register_new_memory(int, struct mem_section *);
 116extern int unregister_memory_section(struct mem_section *);
 117extern int memory_dev_init(void);
 118extern int remove_memory_block(unsigned long, struct mem_section *, int);
 119extern int memory_notify(unsigned long val, void *v);
 120extern int memory_isolate_notify(unsigned long val, void *v);
 121extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 122                                                        struct memory_block *);
 123extern struct memory_block *find_memory_block(struct mem_section *);
 124#define CONFIG_MEM_BLOCK_SIZE   (PAGES_PER_SECTION<<PAGE_SHIFT)
 125enum mem_add_context { BOOT, HOTPLUG };
 126#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 127
 128#ifdef CONFIG_MEMORY_HOTPLUG
 129#define hotplug_memory_notifier(fn, pri) {                      \
 130        static __meminitdata struct notifier_block fn##_mem_nb =\
 131                { .notifier_call = fn, .priority = pri };       \
 132        register_memory_notifier(&fn##_mem_nb);                 \
 133}
 134#else
 135#define hotplug_memory_notifier(fn, pri) do { } while (0)
 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