From 3947be1969a9ce455ec30f60ef51efb10e4323d1 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 29 Oct 2005 18:16:54 -0700 Subject: [PATCH] memory hotplug: sysfs and add/remove functions This adds generic memory add/remove and supporting functions for memory hotplug into a new file as well as a memory hotplug kernel config option. Individual architecture patches will follow. For now, disable memory hotplug when swsusp is enabled. There's a lot of churn there right now. We'll fix it up properly once it calms down. Signed-off-by: Matt Tolentino Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory.h | 94 ++++++++++++++++++++++++++++++++++++++++++ include/linux/memory_hotplug.h | 35 ++++++++++++++++ include/linux/mm.h | 1 + 3 files changed, 130 insertions(+) create mode 100644 include/linux/memory.h (limited to 'include/linux') diff --git a/include/linux/memory.h b/include/linux/memory.h new file mode 100644 index 00000000000..0def328ab5c --- /dev/null +++ b/include/linux/memory.h @@ -0,0 +1,94 @@ +/* + * 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 +#include +#include + +#include + +struct memory_block { + unsigned long phys_index; + unsigned long state; + /* + * This serializes all state change requests. It isn't + * held during creation because the control files are + * created long after the critical areas during + * initialization. + */ + struct semaphore state_sem; + int phys_device; /* to which fru does this belong? */ + void *hw; /* optional pointer to fw/hw data */ + int (*phys_callback)(struct memory_block *); + struct sys_device sysdev; +}; + +/* 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 */ + +/* + * All of these states are currently kernel-internal for notifying + * kernel components and architectures. + * + * For MEM_MAPPING_INVALID, all notifier chains with priority >0 + * are called before pfn_to_page() becomes invalid. The priority=0 + * entry is reserved for the function that actually makes + * pfn_to_page() stop working. Any notifiers that want to be called + * after that should have priority <0. + */ +#define MEM_MAPPING_INVALID (1<<3) + +#ifndef CONFIG_MEMORY_HOTPLUG +static inline int memory_dev_init(void) +{ + return 0; +} +static inline int register_memory_notifier(struct notifier_block *nb) +{ + return 0; +} +static inline void unregister_memory_notifier(struct notifier_block *nb) +{ +} +#else +extern int register_memory(struct memory_block *, struct mem_section *section, struct node *); +extern int register_new_memory(struct mem_section *); +extern int unregister_memory_section(struct mem_section *); +extern int memory_dev_init(void); +extern int register_memory_notifier(struct notifier_block *nb); +extern void unregister_memory_notifier(struct notifier_block *nb); + +#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION< #include +#include +#include #ifdef CONFIG_MEMORY_HOTPLUG /* @@ -46,6 +48,19 @@ static inline void zone_seqlock_init(struct zone *zone) { seqlock_init(&zone->span_seqlock); } +extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages); +extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages); +extern int add_one_highpage(struct page *page, int pfn, int bad_ppro); +/* need some defines for these for archs that don't support it */ +extern void online_page(struct page *page); +/* VM interface that may be used by firmware interface */ +extern int add_memory(u64 start, u64 size); +extern int remove_memory(u64 start, u64 size); +extern int online_pages(unsigned long, unsigned long); + +/* reasonably generic interface to expand the physical pages in a zone */ +extern int __add_pages(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages); #else /* ! CONFIG_MEMORY_HOTPLUG */ /* * Stub functions for when hotplug is off @@ -65,5 +80,25 @@ static inline int zone_span_seqretry(struct zone *zone, unsigned iv) static inline void zone_span_writelock(struct zone *zone) {} static inline void zone_span_writeunlock(struct zone *zone) {} static inline void zone_seqlock_init(struct zone *zone) {} + +static inline int mhp_notimplemented(const char *func) +{ + printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func); + dump_stack(); + return -ENOSYS; +} + +static inline int __add_pages(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages) +{ + return mhp_notimplemented(__FUNCTION__); +} #endif /* ! CONFIG_MEMORY_HOTPLUG */ +static inline int __remove_pages(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages) +{ + printk(KERN_WARNING "%s() called, not yet supported\n", __FUNCTION__); + dump_stack(); + return -ENOSYS; +} #endif /* __LINUX_MEMORY_HOTPLUG_H */ diff --git a/include/linux/mm.h b/include/linux/mm.h index 8a514eca40d..5c1fb0a2e80 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -840,6 +840,7 @@ extern void free_area_init_node(int nid, pg_data_t *pgdat, unsigned long * zones_size, unsigned long zone_start_pfn, unsigned long *zholes_size); extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long); +extern void setup_per_zone_pages_min(void); extern void mem_init(void); extern void show_mem(void); extern void si_meminfo(struct sysinfo * val); -- cgit v1.2.3