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;
  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 device dev;
  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_normal;
  58        int status_change_nid_high;
  59        int status_change_nid;
  60};
  61
  62/*
  63 * During pageblock isolation, count the number of pages within the
  64 * range [start_pfn, start_pfn + nr_pages) which are owned by code
  65 * in the notifier chain.
  66 */
  67#define MEM_ISOLATE_COUNT       (1<<0)
  68
  69struct memory_isolate_notify {
  70        unsigned long start_pfn;        /* Start of range to check */
  71        unsigned int nr_pages;          /* # pages in range to check */
  72        unsigned int pages_found;       /* # pages owned found by callbacks */
  73};
  74
  75struct notifier_block;
  76struct mem_section;
  77
  78/*
  79 * Priorities for the hotplug memory callback routines (stored in decreasing
  80 * order in the callback chain)
  81 */
  82#define SLAB_CALLBACK_PRI       1
  83#define IPC_CALLBACK_PRI        10
  84
  85#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
  86static inline int memory_dev_init(void)
  87{
  88        return 0;
  89}
  90static inline int register_memory_notifier(struct notifier_block *nb)
  91{
  92        return 0;
  93}
  94static inline void unregister_memory_notifier(struct notifier_block *nb)
  95{
  96}
  97static inline int memory_notify(unsigned long val, void *v)
  98{
  99        return 0;
 100}
 101static inline int register_memory_isolate_notifier(struct notifier_block *nb)
 102{
 103        return 0;
 104}
 105static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
 106{
 107}
 108static inline int memory_isolate_notify(unsigned long val, void *v)
 109{
 110        return 0;
 111}
 112#else
 113extern int register_memory_notifier(struct notifier_block *nb);
 114extern void unregister_memory_notifier(struct notifier_block *nb);
 115extern int register_memory_isolate_notifier(struct notifier_block *nb);
 116extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
 117extern int register_new_memory(int, struct mem_section *);
 118#ifdef CONFIG_MEMORY_HOTREMOVE
 119extern int unregister_memory_section(struct mem_section *);
 120#endif
 121extern int memory_dev_init(void);
 122extern int memory_notify(unsigned long val, void *v);
 123extern int memory_isolate_notify(unsigned long val, void *v);
 124extern struct memory_block *find_memory_block_hinted(struct mem_section *,
 125                                                        struct memory_block *);
 126extern struct memory_block *find_memory_block(struct mem_section *);
 127#define CONFIG_MEM_BLOCK_SIZE   (PAGES_PER_SECTION<<PAGE_SHIFT)
 128enum mem_add_context { BOOT, HOTPLUG };
 129#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 130
 131#ifdef CONFIG_MEMORY_HOTPLUG
 132#define hotplug_memory_notifier(fn, pri) ({             \
 133        static __meminitdata struct notifier_block fn##_mem_nb =\
 134                { .notifier_call = fn, .priority = pri };\
 135        register_memory_notifier(&fn##_mem_nb);                 \
 136})
 137#define register_hotmemory_notifier(nb)         register_memory_notifier(nb)
 138#define unregister_hotmemory_notifier(nb)       unregister_memory_notifier(nb)
 139#else
 140#define hotplug_memory_notifier(fn, pri)        ({ 0; })
 141/* These aren't inline functions due to a GCC bug. */
 142#define register_hotmemory_notifier(nb)    ({ (void)(nb); 0; })
 143#define unregister_hotmemory_notifier(nb)  ({ (void)(nb); })
 144#endif
 145
 146/*
 147 * 'struct memory_accessor' is a generic interface to provide
 148 * in-kernel access to persistent memory such as i2c or SPI EEPROMs
 149 */
 150struct memory_accessor {
 151        ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
 152                        size_t count);
 153        ssize_t (*write)(struct memory_accessor *, const char *buf,
 154                         off_t offset, size_t count);
 155};
 156
 157/*
 158 * Kernel text modification mutex, used for code patching. Users of this lock
 159 * can sleep.
 160 */
 161extern struct mutex text_mutex;
 162
 163#endif /* _LINUX_MEMORY_H_ */
 164