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
24 struct 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
43 int 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
53 struct 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
66 struct 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
72 struct notifier_block;
73 struct 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
memory_dev_init(void)83 static inline int memory_dev_init(void)
84 {
85 return 0;
86 }
register_memory_notifier(struct notifier_block * nb)87 static inline int register_memory_notifier(struct notifier_block *nb)
88 {
89 return 0;
90 }
unregister_memory_notifier(struct notifier_block * nb)91 static inline void unregister_memory_notifier(struct notifier_block *nb)
92 {
93 }
memory_notify(unsigned long val,void * v)94 static inline int memory_notify(unsigned long val, void *v)
95 {
96 return 0;
97 }
register_memory_isolate_notifier(struct notifier_block * nb)98 static inline int register_memory_isolate_notifier(struct notifier_block *nb)
99 {
100 return 0;
101 }
unregister_memory_isolate_notifier(struct notifier_block * nb)102 static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
103 {
104 }
memory_isolate_notify(unsigned long val,void * v)105 static inline int memory_isolate_notify(unsigned long val, void *v)
106 {
107 return 0;
108 }
109 #else
110 extern int register_memory_notifier(struct notifier_block *nb);
111 extern void unregister_memory_notifier(struct notifier_block *nb);
112 extern int register_memory_isolate_notifier(struct notifier_block *nb);
113 extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
114 extern int register_new_memory(int, struct mem_section *);
115 extern int unregister_memory_section(struct mem_section *);
116 extern int memory_dev_init(void);
117 extern int remove_memory_block(unsigned long, struct mem_section *, int);
118 extern int memory_notify(unsigned long val, void *v);
119 extern int memory_isolate_notify(unsigned long val, void *v);
120 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
121 struct memory_block *);
122 extern struct memory_block *find_memory_block(struct mem_section *);
123 #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
124 enum 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 */
141 struct 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 */
152 extern struct mutex text_mutex;
153
154 #endif /* _LINUX_MEMORY_H_ */
155