Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * include/linux/memory.h - generic memory definition
4 *
5 * This is mainly for topological representation. We define the
6 * basic "struct memory_block" here, which can be embedded in per-arch
7 * definitions or NUMA information.
8 *
9 * Basic handling of the devices is done in drivers/base/memory.c
10 * and system devices are handled in drivers/base/sys.c.
11 *
12 * Memory block are exported via sysfs in the class/memory/devices/
13 * directory.
14 *
15 */
16#ifndef _LINUX_MEMORY_H_
17#define _LINUX_MEMORY_H_
18
19#include <linux/node.h>
20#include <linux/compiler.h>
21#include <linux/mutex.h>
22#include <linux/notifier.h>
23
24#define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS)
25
26struct memory_block {
27 unsigned long start_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 struct device dev;
33 int nid; /* NID for this memory block */
34};
35
36int arch_get_memory_phys_device(unsigned long start_pfn);
37unsigned long memory_block_size_bytes(void);
38int set_memory_block_size_order(unsigned int order);
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
48struct 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
56struct notifier_block;
57struct mem_section;
58
59/*
60 * Priorities for the hotplug memory callback routines (stored in decreasing
61 * order in the callback chain)
62 */
63#define SLAB_CALLBACK_PRI 1
64#define IPC_CALLBACK_PRI 10
65
66#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
67static inline void memory_dev_init(void)
68{
69 return;
70}
71static inline int register_memory_notifier(struct notifier_block *nb)
72{
73 return 0;
74}
75static inline void unregister_memory_notifier(struct notifier_block *nb)
76{
77}
78static inline int memory_notify(unsigned long val, void *v)
79{
80 return 0;
81}
82#else
83extern int register_memory_notifier(struct notifier_block *nb);
84extern void unregister_memory_notifier(struct notifier_block *nb);
85int create_memory_block_devices(unsigned long start, unsigned long size);
86void remove_memory_block_devices(unsigned long start, unsigned long size);
87extern void memory_dev_init(void);
88extern int memory_notify(unsigned long val, void *v);
89extern struct memory_block *find_memory_block(struct mem_section *);
90typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *);
91extern int walk_memory_blocks(unsigned long start, unsigned long size,
92 void *arg, walk_memory_blocks_func_t func);
93extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func);
94#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
95#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
96
97#ifdef CONFIG_MEMORY_HOTPLUG
98#define hotplug_memory_notifier(fn, pri) ({ \
99 static __meminitdata struct notifier_block fn##_mem_nb =\
100 { .notifier_call = fn, .priority = pri };\
101 register_memory_notifier(&fn##_mem_nb); \
102})
103#define register_hotmemory_notifier(nb) register_memory_notifier(nb)
104#define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb)
105#else
106#define hotplug_memory_notifier(fn, pri) ({ 0; })
107/* These aren't inline functions due to a GCC bug. */
108#define register_hotmemory_notifier(nb) ({ (void)(nb); 0; })
109#define unregister_hotmemory_notifier(nb) ({ (void)(nb); })
110#endif
111
112/*
113 * Kernel text modification mutex, used for code patching. Users of this lock
114 * can sleep.
115 */
116extern struct mutex text_mutex;
117
118#endif /* _LINUX_MEMORY_H_ */