/* SPDX-License-Identifier: GPL-2.0 */ /* * include/linux/memory.h - generic memory definition * * This is mainly for topological representation. We define the * basic "struct memory_block" here, which can be embedded in per-arch * definitions or NUMA information. * * Basic handling of the devices is done in drivers/base/memory.c * and system devices are handled in drivers/base/sys.c. * * Memory block are exported via sysfs in the class/memory/devices/ * directory. * */ #ifndef _LINUX_MEMORY_H_ #define _LINUX_MEMORY_H_ #include <linux/node.h> #include <linux/compiler.h> #include <linux/mutex.h> #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) /** * struct memory_group - a logical group of memory blocks * @nid: The node id for all memory blocks inside the memory group. * @blocks: List of all memory blocks belonging to this memory group. * @present_kernel_pages: Present (online) memory outside ZONE_MOVABLE of this * memory group. * @present_movable_pages: Present (online) memory in ZONE_MOVABLE of this * memory group. * @is_dynamic: The memory group type: static vs. dynamic * @s.max_pages: Valid with &memory_group.is_dynamic == false. The maximum * number of pages we'll have in this static memory group. * @d.unit_pages: Valid with &memory_group.is_dynamic == true. Unit in pages * in which memory is added/removed in this dynamic memory group. * This granularity defines the alignment of a unit in physical * address space; it has to be at least as big as a single * memory block. * * A memory group logically groups memory blocks; each memory block * belongs to at most one memory group. A memory group corresponds to * a memory device, such as a DIMM or a NUMA node, which spans multiple * memory blocks and might even span multiple non-contiguous physical memory * ranges. * * Modification of members after registration is serialized by memory * hot(un)plug code. */ struct memory_group { int nid; struct list_head memory_blocks; unsigned long present_kernel_pages; unsigned long present_movable_pages; bool is_dynamic; union { struct { unsigned long max_pages; } s; struct { unsigned long unit_pages; } d; }; }; struct memory_block { unsigned long start_section_nr; unsigned long state; /* serialized by the dev->lock */ int online_type; /* for passing data to online routine */ int nid; /* NID for this memory block */ /* * The single zone of this memory block if all PFNs of this memory block * that are System RAM (not a memory hole, not ZONE_DEVICE ranges) are * managed by a single zone. NULL if multiple zones (including nodes) * apply. */ struct zone *zone; struct device dev; struct vmem_altmap *altmap; struct memory_group *group; /* group (if any) for this block */ struct list_head group_next; /* next block inside memory group */ #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) atomic_long_t nr_hwpoison; #endif }; int arch_get_memory_phys_device(unsigned long start_pfn); unsigned long memory_block_size_bytes(void); int set_memory_block_size_order(unsigned int order); /* These states are exposed to userspace as text strings in sysfs */ #define MEM_ONLINE (1<<0) /* exposed to userspace */ #define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */ #define MEM_OFFLINE (1<<2) /* exposed to userspace */ #define MEM_GOING_ONLINE (1<<3) #define MEM_CANCEL_ONLINE (1<<4) #define MEM_CANCEL_OFFLINE (1<<5) #define MEM_PREPARE_ONLINE (1<<6) #define MEM_FINISH_OFFLINE (1<<7) struct memory_notify { /* * The altmap_start_pfn and altmap_nr_pages fields are designated for * specifying the altmap range and are exclusively intended for use in * MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers. */ unsigned long altmap_start_pfn; unsigned long altmap_nr_pages; unsigned long start_pfn; unsigned long nr_pages; int status_change_nid_normal; int status_change_nid; }; struct notifier_block; struct mem_section; /* * Priorities for the hotplug memory callback routines (stored in decreasing * order in the callback chain) */ #define DEFAULT_CALLBACK_PRI 0 #define SLAB_CALLBACK_PRI 1 #define HMAT_CALLBACK_PRI 2 #define CXL_CALLBACK_PRI 5 #define MM_COMPUTE_BATCH_PRI 10 #define CPUSET_CALLBACK_PRI 10 #define MEMTIER_HOTPLUG_PRI 100 #define KSM_CALLBACK_PRI 100 #ifndef CONFIG_MEMORY_HOTPLUG static inline void memory_dev_init(void) { return; } static inline int register_memory_notifier(struct notifier_block *nb) { return 0; } static inline void unregister_memory_notifier(struct notifier_block *nb) { } static inline int memory_notify(unsigned long val, void *v) { return 0; } static inline int hotplug_memory_notifier(notifier_fn_t fn, int pri) { return 0; } #else /* CONFIG_MEMORY_HOTPLUG */ extern int register_memory_notifier(struct notifier_block *nb); extern void unregister_memory_notifier(struct notifier_block *nb); int create_memory_block_devices(unsigned long start, unsigned long size, struct vmem_altmap *altmap, struct memory_group *group); void remove_memory_block_devices(unsigned long start, unsigned long size); extern void memory_dev_init(void); extern int memory_notify(unsigned long val, void *v); extern struct memory_block *find_memory_block(unsigned long section_nr); typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *); extern int walk_memory_blocks(unsigned long start, unsigned long size, void *arg, walk_memory_blocks_func_t func); extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func); extern int memory_group_register_static(int nid, unsigned long max_pages); extern int memory_group_register_dynamic(int nid, unsigned long unit_pages); extern int memory_group_unregister(int mgid); struct memory_group *memory_group_find_by_id(int mgid); typedef int (*walk_memory_groups_func_t)(struct memory_group *, void *); int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func, struct memory_group *excluded, void *arg); #define hotplug_memory_notifier(fn, pri) ({ \ static __meminitdata struct notifier_block fn##_mem_nb =\ { .notifier_call = fn, .priority = pri };\ register_memory_notifier(&fn##_mem_nb); \ }) #ifdef CONFIG_NUMA void memory_block_add_nid(struct memory_block *mem, int nid, enum meminit_context context); #endif /* CONFIG_NUMA */ #endif /* CONFIG_MEMORY_HOTPLUG */ /* * Kernel text modification mutex, used for code patching. Users of this lock * can sleep. */ extern struct mutex text_mutex; #endif /* _LINUX_MEMORY_H_ */