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 | |
23 | #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) |
24 | |
25 | /** |
26 | * struct memory_group - a logical group of memory blocks |
27 | * @nid: The node id for all memory blocks inside the memory group. |
28 | * @blocks: List of all memory blocks belonging to this memory group. |
29 | * @present_kernel_pages: Present (online) memory outside ZONE_MOVABLE of this |
30 | * memory group. |
31 | * @present_movable_pages: Present (online) memory in ZONE_MOVABLE of this |
32 | * memory group. |
33 | * @is_dynamic: The memory group type: static vs. dynamic |
34 | * @s.max_pages: Valid with &memory_group.is_dynamic == false. The maximum |
35 | * number of pages we'll have in this static memory group. |
36 | * @d.unit_pages: Valid with &memory_group.is_dynamic == true. Unit in pages |
37 | * in which memory is added/removed in this dynamic memory group. |
38 | * This granularity defines the alignment of a unit in physical |
39 | * address space; it has to be at least as big as a single |
40 | * memory block. |
41 | * |
42 | * A memory group logically groups memory blocks; each memory block |
43 | * belongs to at most one memory group. A memory group corresponds to |
44 | * a memory device, such as a DIMM or a NUMA node, which spans multiple |
45 | * memory blocks and might even span multiple non-contiguous physical memory |
46 | * ranges. |
47 | * |
48 | * Modification of members after registration is serialized by memory |
49 | * hot(un)plug code. |
50 | */ |
51 | struct memory_group { |
52 | int nid; |
53 | struct list_head memory_blocks; |
54 | unsigned long present_kernel_pages; |
55 | unsigned long present_movable_pages; |
56 | bool is_dynamic; |
57 | union { |
58 | struct { |
59 | unsigned long max_pages; |
60 | } s; |
61 | struct { |
62 | unsigned long unit_pages; |
63 | } d; |
64 | }; |
65 | }; |
66 | |
67 | struct memory_block { |
68 | unsigned long start_section_nr; |
69 | unsigned long state; /* serialized by the dev->lock */ |
70 | int online_type; /* for passing data to online routine */ |
71 | int nid; /* NID for this memory block */ |
72 | /* |
73 | * The single zone of this memory block if all PFNs of this memory block |
74 | * that are System RAM (not a memory hole, not ZONE_DEVICE ranges) are |
75 | * managed by a single zone. NULL if multiple zones (including nodes) |
76 | * apply. |
77 | */ |
78 | struct zone *zone; |
79 | struct device dev; |
80 | struct vmem_altmap *altmap; |
81 | struct memory_group *group; /* group (if any) for this block */ |
82 | struct list_head group_next; /* next block inside memory group */ |
83 | #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) |
84 | atomic_long_t nr_hwpoison; |
85 | #endif |
86 | }; |
87 | |
88 | int arch_get_memory_phys_device(unsigned long start_pfn); |
89 | unsigned long memory_block_size_bytes(void); |
90 | int set_memory_block_size_order(unsigned int order); |
91 | |
92 | /* These states are exposed to userspace as text strings in sysfs */ |
93 | #define MEM_ONLINE (1<<0) /* exposed to userspace */ |
94 | #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */ |
95 | #define MEM_OFFLINE (1<<2) /* exposed to userspace */ |
96 | #define MEM_GOING_ONLINE (1<<3) |
97 | #define MEM_CANCEL_ONLINE (1<<4) |
98 | #define MEM_CANCEL_OFFLINE (1<<5) |
99 | #define MEM_PREPARE_ONLINE (1<<6) |
100 | #define MEM_FINISH_OFFLINE (1<<7) |
101 | |
102 | struct memory_notify { |
103 | /* |
104 | * The altmap_start_pfn and altmap_nr_pages fields are designated for |
105 | * specifying the altmap range and are exclusively intended for use in |
106 | * MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers. |
107 | */ |
108 | unsigned long altmap_start_pfn; |
109 | unsigned long altmap_nr_pages; |
110 | unsigned long start_pfn; |
111 | unsigned long nr_pages; |
112 | int status_change_nid_normal; |
113 | int status_change_nid; |
114 | }; |
115 | |
116 | struct notifier_block; |
117 | struct mem_section; |
118 | |
119 | /* |
120 | * Priorities for the hotplug memory callback routines (stored in decreasing |
121 | * order in the callback chain) |
122 | */ |
123 | #define DEFAULT_CALLBACK_PRI 0 |
124 | #define SLAB_CALLBACK_PRI 1 |
125 | #define HMAT_CALLBACK_PRI 2 |
126 | #define CXL_CALLBACK_PRI 5 |
127 | #define MM_COMPUTE_BATCH_PRI 10 |
128 | #define CPUSET_CALLBACK_PRI 10 |
129 | #define MEMTIER_HOTPLUG_PRI 100 |
130 | #define KSM_CALLBACK_PRI 100 |
131 | |
132 | #ifndef CONFIG_MEMORY_HOTPLUG |
133 | static inline void memory_dev_init(void) |
134 | { |
135 | return; |
136 | } |
137 | static inline int register_memory_notifier(struct notifier_block *nb) |
138 | { |
139 | return 0; |
140 | } |
141 | static inline void unregister_memory_notifier(struct notifier_block *nb) |
142 | { |
143 | } |
144 | static inline int memory_notify(unsigned long val, void *v) |
145 | { |
146 | return 0; |
147 | } |
148 | static inline int hotplug_memory_notifier(notifier_fn_t fn, int pri) |
149 | { |
150 | return 0; |
151 | } |
152 | #else /* CONFIG_MEMORY_HOTPLUG */ |
153 | extern int register_memory_notifier(struct notifier_block *nb); |
154 | extern void unregister_memory_notifier(struct notifier_block *nb); |
155 | int create_memory_block_devices(unsigned long start, unsigned long size, |
156 | struct vmem_altmap *altmap, |
157 | struct memory_group *group); |
158 | void remove_memory_block_devices(unsigned long start, unsigned long size); |
159 | extern void memory_dev_init(void); |
160 | extern int memory_notify(unsigned long val, void *v); |
161 | extern struct memory_block *find_memory_block(unsigned long section_nr); |
162 | typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *); |
163 | extern int walk_memory_blocks(unsigned long start, unsigned long size, |
164 | void *arg, walk_memory_blocks_func_t func); |
165 | extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func); |
166 | |
167 | extern int memory_group_register_static(int nid, unsigned long max_pages); |
168 | extern int memory_group_register_dynamic(int nid, unsigned long unit_pages); |
169 | extern int memory_group_unregister(int mgid); |
170 | struct memory_group *memory_group_find_by_id(int mgid); |
171 | typedef int (*walk_memory_groups_func_t)(struct memory_group *, void *); |
172 | int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func, |
173 | struct memory_group *excluded, void *arg); |
174 | #define hotplug_memory_notifier(fn, pri) ({ \ |
175 | static __meminitdata struct notifier_block fn##_mem_nb =\ |
176 | { .notifier_call = fn, .priority = pri };\ |
177 | register_memory_notifier(&fn##_mem_nb); \ |
178 | }) |
179 | |
180 | #ifdef CONFIG_NUMA |
181 | void memory_block_add_nid(struct memory_block *mem, int nid, |
182 | enum meminit_context context); |
183 | #endif /* CONFIG_NUMA */ |
184 | #endif /* CONFIG_MEMORY_HOTPLUG */ |
185 | |
186 | /* |
187 | * Kernel text modification mutex, used for code patching. Users of this lock |
188 | * can sleep. |
189 | */ |
190 | extern struct mutex text_mutex; |
191 | |
192 | #endif /* _LINUX_MEMORY_H_ */ |
193 | |