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
25 struct memory_block {
26 unsigned long start_section_nr;
27 unsigned long end_section_nr;
28 unsigned long state; /* serialized by the dev->lock */
29 int section_count; /* serialized by mem_sysfs_mutex */
30 int online_type; /* for passing data to online routine */
31 int phys_device; /* to which fru does this belong? */
32 void *hw; /* optional pointer to fw/hw data */
33 int (*phys_callback)(struct memory_block *);
34 struct device dev;
35 };
36
37 int arch_get_memory_phys_device(unsigned long start_pfn);
38 unsigned long memory_block_size_bytes(void);
39
40 /* These states are exposed to userspace as text strings in sysfs */
41 #define MEM_ONLINE (1<<0) /* exposed to userspace */
42 #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */
43 #define MEM_OFFLINE (1<<2) /* exposed to userspace */
44 #define MEM_GOING_ONLINE (1<<3)
45 #define MEM_CANCEL_ONLINE (1<<4)
46 #define MEM_CANCEL_OFFLINE (1<<5)
47
48 struct memory_notify {
49 unsigned long start_pfn;
50 unsigned long nr_pages;
51 int status_change_nid_normal;
52 int status_change_nid_high;
53 int status_change_nid;
54 };
55
56 /*
57 * During pageblock isolation, count the number of pages within the
58 * range [start_pfn, start_pfn + nr_pages) which are owned by code
59 * in the notifier chain.
60 */
61 #define MEM_ISOLATE_COUNT (1<<0)
62
63 struct memory_isolate_notify {
64 unsigned long start_pfn; /* Start of range to check */
65 unsigned int nr_pages; /* # pages in range to check */
66 unsigned int pages_found; /* # pages owned found by callbacks */
67 };
68
69 struct notifier_block;
70 struct mem_section;
71
72 /*
73 * Priorities for the hotplug memory callback routines (stored in decreasing
74 * order in the callback chain)
75 */
76 #define SLAB_CALLBACK_PRI 1
77 #define IPC_CALLBACK_PRI 10
78
79 #ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
memory_dev_init(void)80 static inline int memory_dev_init(void)
81 {
82 return 0;
83 }
register_memory_notifier(struct notifier_block * nb)84 static inline int register_memory_notifier(struct notifier_block *nb)
85 {
86 return 0;
87 }
unregister_memory_notifier(struct notifier_block * nb)88 static inline void unregister_memory_notifier(struct notifier_block *nb)
89 {
90 }
memory_notify(unsigned long val,void * v)91 static inline int memory_notify(unsigned long val, void *v)
92 {
93 return 0;
94 }
register_memory_isolate_notifier(struct notifier_block * nb)95 static inline int register_memory_isolate_notifier(struct notifier_block *nb)
96 {
97 return 0;
98 }
unregister_memory_isolate_notifier(struct notifier_block * nb)99 static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
100 {
101 }
memory_isolate_notify(unsigned long val,void * v)102 static inline int memory_isolate_notify(unsigned long val, void *v)
103 {
104 return 0;
105 }
106 #else
107 extern int register_memory_notifier(struct notifier_block *nb);
108 extern void unregister_memory_notifier(struct notifier_block *nb);
109 extern int register_memory_isolate_notifier(struct notifier_block *nb);
110 extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
111 extern int register_new_memory(int, struct mem_section *);
112 #ifdef CONFIG_MEMORY_HOTREMOVE
113 extern int unregister_memory_section(struct mem_section *);
114 #endif
115 extern int memory_dev_init(void);
116 extern int memory_notify(unsigned long val, void *v);
117 extern int memory_isolate_notify(unsigned long val, void *v);
118 extern struct memory_block *find_memory_block_hinted(struct mem_section *,
119 struct memory_block *);
120 extern struct memory_block *find_memory_block(struct mem_section *);
121 #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
122 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
123
124 #ifdef CONFIG_MEMORY_HOTPLUG
125 #define hotplug_memory_notifier(fn, pri) ({ \
126 static __meminitdata struct notifier_block fn##_mem_nb =\
127 { .notifier_call = fn, .priority = pri };\
128 register_memory_notifier(&fn##_mem_nb); \
129 })
130 #define register_hotmemory_notifier(nb) register_memory_notifier(nb)
131 #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb)
132 #else
133 #define hotplug_memory_notifier(fn, pri) ({ 0; })
134 /* These aren't inline functions due to a GCC bug. */
135 #define register_hotmemory_notifier(nb) ({ (void)(nb); 0; })
136 #define unregister_hotmemory_notifier(nb) ({ (void)(nb); })
137 #endif
138
139 /*
140 * 'struct memory_accessor' is a generic interface to provide
141 * in-kernel access to persistent memory such as i2c or SPI EEPROMs
142 */
143 struct memory_accessor {
144 ssize_t (*read)(struct memory_accessor *, char *buf, off_t offset,
145 size_t count);
146 ssize_t (*write)(struct memory_accessor *, const char *buf,
147 off_t offset, size_t count);
148 };
149
150 /*
151 * Kernel text modification mutex, used for code patching. Users of this lock
152 * can sleep.
153 */
154 extern struct mutex text_mutex;
155
156 #endif /* _LINUX_MEMORY_H_ */
157