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 online_type; /* for passing data to online routine */
30 int nid; /* NID for this memory block */
31 struct device dev;
32 /*
33 * Number of vmemmap pages. These pages
34 * lay at the beginning of the memory block.
35 */
36 unsigned long nr_vmemmap_pages;
37};
38
39int arch_get_memory_phys_device(unsigned long start_pfn);
40unsigned long memory_block_size_bytes(void);
41int set_memory_block_size_order(unsigned int order);
42
43/* These states are exposed to userspace as text strings in sysfs */
44#define MEM_ONLINE (1<<0) /* exposed to userspace */
45#define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */
46#define MEM_OFFLINE (1<<2) /* exposed to userspace */
47#define MEM_GOING_ONLINE (1<<3)
48#define MEM_CANCEL_ONLINE (1<<4)
49#define MEM_CANCEL_OFFLINE (1<<5)
50
51struct memory_notify {
52 unsigned long start_pfn;
53 unsigned long nr_pages;
54 int status_change_nid_normal;
55 int status_change_nid_high;
56 int status_change_nid;
57};
58
59struct notifier_block;
60struct mem_section;
61
62/*
63 * Priorities for the hotplug memory callback routines (stored in decreasing
64 * order in the callback chain)
65 */
66#define SLAB_CALLBACK_PRI 1
67#define IPC_CALLBACK_PRI 10
68
69#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
70static inline void memory_dev_init(void)
71{
72 return;
73}
74static inline int register_memory_notifier(struct notifier_block *nb)
75{
76 return 0;
77}
78static inline void unregister_memory_notifier(struct notifier_block *nb)
79{
80}
81static inline int memory_notify(unsigned long val, void *v)
82{
83 return 0;
84}
85#else
86extern int register_memory_notifier(struct notifier_block *nb);
87extern void unregister_memory_notifier(struct notifier_block *nb);
88int create_memory_block_devices(unsigned long start, unsigned long size,
89 unsigned long vmemmap_pages);
90void remove_memory_block_devices(unsigned long start, unsigned long size);
91extern void memory_dev_init(void);
92extern int memory_notify(unsigned long val, void *v);
93extern struct memory_block *find_memory_block(struct mem_section *);
94typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *);
95extern int walk_memory_blocks(unsigned long start, unsigned long size,
96 void *arg, walk_memory_blocks_func_t func);
97extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func);
98#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
99#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
100
101#ifdef CONFIG_MEMORY_HOTPLUG
102#define hotplug_memory_notifier(fn, pri) ({ \
103 static __meminitdata struct notifier_block fn##_mem_nb =\
104 { .notifier_call = fn, .priority = pri };\
105 register_memory_notifier(&fn##_mem_nb); \
106})
107#define register_hotmemory_notifier(nb) register_memory_notifier(nb)
108#define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb)
109#else
110#define hotplug_memory_notifier(fn, pri) ({ 0; })
111/* These aren't inline functions due to a GCC bug. */
112#define register_hotmemory_notifier(nb) ({ (void)(nb); 0; })
113#define unregister_hotmemory_notifier(nb) ({ (void)(nb); })
114#endif
115
116/*
117 * Kernel text modification mutex, used for code patching. Users of this lock
118 * can sleep.
119 */
120extern struct mutex text_mutex;
121
122#endif /* _LINUX_MEMORY_H_ */