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