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
  22#define MIN_MEMORY_BLOCK_SIZE     (1UL << SECTION_SIZE_BITS)
  23
  24struct memory_block {
  25        unsigned long start_section_nr;
  26        unsigned long end_section_nr;
  27        unsigned long state;
  28        int section_count;
  29
  30        /*
  31         * This serializes all state change requests.  It isn't
  32         * held during creation because the control files are
  33         * created long after the critical areas during
  34         * initialization.
  35         */
  36        struct mutex state_mutex;
  37        int phys_device;                /* to which fru does this belong? */
  38        void *hw;                       /* optional pointer to fw/hw data */
  39        int (*phys_callback)(struct memory_block *);
  40        struct device dev;
  41};
  42
  43int arch_get_memory_phys_device(unsigned long start_pfn);
  44
  45/* These states are exposed to userspace as text strings in sysfs */
  46#define MEM_ONLINE              (1<<0) /* exposed to userspace */
  47#define MEM_GOING_OFFLINE       (1<<1) /* exposed to userspace */
  48#define MEM_OFFLINE             (1<<2) /* exposed to userspace */
  49#define MEM_GOING_ONLINE        (1<<3)
  50#define MEM_CANCEL_ONLINE       (1<<4)
  51#define MEM_CANCEL_OFFLINE      (1<<5)
  52
  53struct memory_notify {
  54        unsigned long start_pfn;
  55        unsigned long nr_pages;
  56        int status_change_nid;
  57};
  58
  59/*
  60 * During pageblock isolation, count the number of pages within the
  61 * range [start_pfn, start_pfn + nr_pages) which are owned by code
  62 * in the notifier chain.
  63 */
  64#define MEM_ISOLATE_COUNT       (1<<0)
  65
  66struct memory_isolate_notify {
  67        unsigned long start_pfn;        /* Start of range to check */
  68        unsigned int nr_pages;          /* # pages in range to check */
  69        unsigned int pages_found;       /* # pages owned found by callbacks */
  70};
  71
  72struct notifier_block;
  73struct mem_section;
  74
  75/*
  76 * Priorities for the hotplug memory callback routines (stored in decreasing
  77 * order in the callback chain)
  78 */
  79#define SLAB_CALLBACK_PRI       1
  80#define IPC_CALLBACK_PRI        10
  81
  82#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
  83static inline int memory_dev_init(void)
  84{
  85        return 0;
  86}
  87static inline int register_memory_notifier(struct notifier_block *nb)
  88{
  89        return 0;
  90}
  91static inline void unregister_memory_notifier(struct notifier_block *nb)
  92{
  93}
  94static inline int memory_notify(unsigned long val, void *v)
  95{
  96        return 0;
  97}
  98static inline int register_memory_isolate_notifier(struct notifier_block *nb)
  99{
 100        return 0;
 101}
 102static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
 103{
 104}
 105static inline int memory_isolate_notify(unsigned long val, void *v)
 106{
 107        return 0;
 108}
 109#else
 110extern int register_memory_notifier(struct notifier_block *nb);
 111extern void unregister_memory_notifier(struct notifier_block *nb);
 112extern int register_memory_isolate_notifier(struct notifier_block *nb);
 113extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
 114extern int register_new_memory(int, struct mem_section *);
 115extern int unregister_memory_section(struct mem_section *);
 116extern int memory_dev_init(void);
 117extern int remove_memory_block(unsigned long, struct mem_section *, int);
 118extern int memory_notify(unsigned long val, void *v);
 119extern int memory_isolate_notify(unsigned long val, void *v);
 120extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 121                                                        struct memory_block *);
 122extern struct memory_block *find_memory_block(struct mem_section *);
 123#define CONFIG_MEM_BLOCK_SIZE   (PAGES_PER_SECTION<<PAGE_SHIFT)
 124enum mem_add_context { BOOT, HOTPLUG };
 125#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 126
 127#ifdef CONFIG_MEMORY_HOTPLUG
 128#define hotplug_memory_notifier(fn, pri) {                      \
 129        static __meminitdata struct notifier_block fn##_mem_nb =\
 130                { .notifier_call = fn, .priority = pri };       \
 131        register_memory_notifier(&fn##_mem_nb);                 \
 132}
 133#else
 134#define hotplug_memory_notifier(fn, pri) do { } while (0)
 135#endif
 136
 137/*
 138 * 'struct memory_accessor' is a generic interface to provide
 139 * in-kernel access to persistent memory such as i2c or SPI EEPROMs
 140 */
 141struct memory_accessor {
 142        ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
 143                        size_t count);
 144        ssize_t (*write)(struct memory_accessor *, const char *buf,
 145                         off_t offset, size_t count);
 146};
 147
 148/*
 149 * Kernel text modification mutex, used for code patching. Users of this lock
 150 * can sleep.
 151 */
 152extern struct mutex text_mutex;
 153
 154#endif /* _LINUX_MEMORY_H_ */
 155