root/include/linux/memory.h

INCLUDED FROM

DEFINITIONS

1. memory_dev_init
2. register_memory_notifier
3. unregister_memory_notifier
4. memory_notify
5. register_memory_isolate_notifier
6. unregister_memory_isolate_notifier
7. memory_isolate_notify

/*
 * include/linux/memory.h - generic memory definition
 *
 * This is mainly for topological representation. We define the
 * basic "struct memory_block" here, which can be embedded in per-arch
 * definitions or NUMA information.
 *
 * Basic handling of the devices is done in drivers/base/memory.c
 * and system devices are handled in drivers/base/sys.c.
 *
 * Memory block are exported via sysfs in the class/memory/devices/
 * directory.
 *
 */
#ifndef _LINUX_MEMORY_H_
#define _LINUX_MEMORY_H_

#include <linux/node.h>
#include <linux/compiler.h>
#include <linux/mutex.h>
#include <linux/notifier.h>

#define MIN_MEMORY_BLOCK_SIZE     (1UL << SECTION_SIZE_BITS)

struct memory_block {
        unsigned long start_section_nr;
        unsigned long end_section_nr;
        unsigned long state;            /* serialized by the dev->lock */
        int section_count;              /* serialized by mem_sysfs_mutex */
        int online_type;                /* for passing data to online routine */
        int phys_device;                /* to which fru does this belong? */
        void *hw;                       /* optional pointer to fw/hw data */
        int (*phys_callback)(struct memory_block *);
        struct device dev;
};

int arch_get_memory_phys_device(unsigned long start_pfn);
unsigned long memory_block_size_bytes(void);

/* These states are exposed to userspace as text strings in sysfs */
#define MEM_ONLINE              (1<<0) /* exposed to userspace */
#define MEM_GOING_OFFLINE       (1<<1) /* exposed to userspace */
#define MEM_OFFLINE             (1<<2) /* exposed to userspace */
#define MEM_GOING_ONLINE        (1<<3)
#define MEM_CANCEL_ONLINE       (1<<4)
#define MEM_CANCEL_OFFLINE      (1<<5)

struct memory_notify {
        unsigned long start_pfn;
        unsigned long nr_pages;
        int status_change_nid_normal;
        int status_change_nid_high;
        int status_change_nid;
};

/*
 * During pageblock isolation, count the number of pages within the
 * range [start_pfn, start_pfn + nr_pages) which are owned by code
 * in the notifier chain.
 */
#define MEM_ISOLATE_COUNT       (1<<0)

struct memory_isolate_notify {
        unsigned long start_pfn;        /* Start of range to check */
        unsigned int nr_pages;          /* # pages in range to check */
        unsigned int pages_found;       /* # pages owned found by callbacks */
};

struct notifier_block;
struct mem_section;

/*
 * Priorities for the hotplug memory callback routines (stored in decreasing
 * order in the callback chain)
 */
#define SLAB_CALLBACK_PRI       1
#define IPC_CALLBACK_PRI        10

#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
static inline int memory_dev_init(void)
{
        return 0;
}
static inline int register_memory_notifier(struct notifier_block *nb)
{
        return 0;
}
static inline void unregister_memory_notifier(struct notifier_block *nb)
{
}
static inline int memory_notify(unsigned long val, void *v)
{
        return 0;
}
static inline int register_memory_isolate_notifier(struct notifier_block *nb)
{
        return 0;
}
static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
{
}
static inline int memory_isolate_notify(unsigned long val, void *v)
{
        return 0;
}
#else
extern int register_memory_notifier(struct notifier_block *nb);
extern void unregister_memory_notifier(struct notifier_block *nb);
extern int register_memory_isolate_notifier(struct notifier_block *nb);
extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
extern int register_new_memory(int, struct mem_section *);
#ifdef CONFIG_MEMORY_HOTREMOVE
extern int unregister_memory_section(struct mem_section *);
#endif
extern int memory_dev_init(void);
extern int memory_notify(unsigned long val, void *v);
extern int memory_isolate_notify(unsigned long val, void *v);
extern struct memory_block *find_memory_block_hinted(struct mem_section *,
                                                        struct memory_block *);
extern struct memory_block *find_memory_block(struct mem_section *);
#define CONFIG_MEM_BLOCK_SIZE   (PAGES_PER_SECTION<<PAGE_SHIFT)
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */

#ifdef CONFIG_MEMORY_HOTPLUG
#define hotplug_memory_notifier(fn, pri) ({             \
        static __meminitdata struct notifier_block fn##_mem_nb =\
                { .notifier_call = fn, .priority = pri };\
        register_memory_notifier(&fn##_mem_nb);                 \
})
#define register_hotmemory_notifier(nb)         register_memory_notifier(nb)
#define unregister_hotmemory_notifier(nb)       unregister_memory_notifier(nb)
#else
#define hotplug_memory_notifier(fn, pri)        ({ 0; })
/* These aren't inline functions due to a GCC bug. */
#define register_hotmemory_notifier(nb)    ({ (void)(nb); 0; })
#define unregister_hotmemory_notifier(nb)  ({ (void)(nb); })
#endif

/*
 * 'struct memory_accessor' is a generic interface to provide
 * in-kernel access to persistent memory such as i2c or SPI EEPROMs
 */
struct memory_accessor {
        ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
                        size_t count);
        ssize_t (*write)(struct memory_accessor *, const char *buf,
                         off_t offset, size_t count);
};

/*
 * Kernel text modification mutex, used for code patching. Users of this lock
 * can sleep.
 */
extern struct mutex text_mutex;

#endif /* _LINUX_MEMORY_H_ */