lkml.org 
[lkml]   [2005]   [Aug]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Subject[RFC][PATCH 08/12] memory hotplug: sysfs and add/remove functions
    From
    Date

    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 <matthew.e.tolentino@intel.com>
    Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
    ---

    memhotplug-dave/drivers/base/Makefile | 1
    memhotplug-dave/drivers/base/init.c | 2
    memhotplug-dave/drivers/base/memory.c | 455 +++++++++++++++++++++++++
    memhotplug-dave/include/linux/memory.h | 94 +++++
    memhotplug-dave/include/linux/memory_hotplug.h | 35 +
    memhotplug-dave/include/linux/mm.h | 1
    memhotplug-dave/mm/Kconfig | 8
    memhotplug-dave/mm/Makefile | 2
    memhotplug-dave/mm/memory_hotplug.c | 178 +++++++++
    memhotplug-dave/mm/page_alloc.c | 4
    mm/sparse.c | 0
    11 files changed, 777 insertions(+), 3 deletions(-)

    diff -puN drivers/base/Makefile~D0-sysfs-memory-class drivers/base/Makefile
    --- memhotplug/drivers/base/Makefile~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/drivers/base/Makefile 2005-08-12 07:43:48.000000000 -0700
    @@ -7,6 +7,7 @@ obj-y := core.o sys.o bus.o dd.o \
    obj-y += power/
    obj-$(CONFIG_FW_LOADER) += firmware_class.o
    obj-$(CONFIG_NUMA) += node.o
    +obj-$(CONFIG_MEMORY_HOTPLUG) += memory.o

    ifeq ($(CONFIG_DEBUG_DRIVER),y)
    EXTRA_CFLAGS += -DDEBUG
    diff -puN drivers/base/init.c~D0-sysfs-memory-class drivers/base/init.c
    --- memhotplug/drivers/base/init.c~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/drivers/base/init.c 2005-08-12 07:43:48.000000000 -0700
    @@ -9,6 +9,7 @@

    #include <linux/device.h>
    #include <linux/init.h>
    +#include <linux/memory.h>

    extern int devices_init(void);
    extern int buses_init(void);
    @@ -39,5 +40,6 @@ void __init driver_init(void)
    platform_bus_init();
    system_bus_init();
    cpu_dev_init();
    + memory_dev_init();
    attribute_container_init();
    }
    diff -puN /dev/null drivers/base/memory.c
    --- /dev/null 2005-03-30 22:36:15.000000000 -0800
    +++ memhotplug-dave/drivers/base/memory.c 2005-08-12 07:43:48.000000000 -0700
    @@ -0,0 +1,455 @@
    +/*
    + * drivers/base/memory.c - basic Memory class support
    + *
    + * Written by Matt Tolentino <matthew.e.tolentino@intel.com>
    + * Dave Hansen <haveblue@us.ibm.com>
    + *
    + * This file provides the necessary infrastructure to represent
    + * a SPARSEMEM-memory-model system's physical memory in /sysfs.
    + * All arch-independent code that assumes MEMORY_HOTPLUG requires
    + * SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
    + */
    +
    +#include <linux/sysdev.h>
    +#include <linux/module.h>
    +#include <linux/init.h>
    +#include <linux/sched.h> /* capable() */
    +#include <linux/topology.h>
    +#include <linux/device.h>
    +#include <linux/memory.h>
    +#include <linux/kobject.h>
    +#include <linux/memory_hotplug.h>
    +#include <linux/mm.h>
    +#include <asm/atomic.h>
    +#include <asm/uaccess.h>
    +
    +#define MEMORY_CLASS_NAME "memory"
    +
    +struct sysdev_class memory_sysdev_class = {
    + set_kset_name(MEMORY_CLASS_NAME),
    +};
    +EXPORT_SYMBOL(memory_sysdev_class);
    +
    +static char *memory_hotplug_name(struct kset *kset, struct kobject *kobj)
    +{
    + return MEMORY_CLASS_NAME;
    +}
    +
    +static int memory_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
    + int num_envp, char *buffer, int buffer_size)
    +{
    + int retval = 0;
    +
    + return retval;
    +}
    +
    +static struct kset_hotplug_ops memory_hotplug_ops = {
    + .name = memory_hotplug_name,
    + .hotplug = memory_hotplug,
    +};
    +
    +static struct notifier_block *memory_chain;
    +
    +int register_memory_notifier(struct notifier_block *nb)
    +{
    + return notifier_chain_register(&memory_chain, nb);
    +}
    +
    +void unregister_memory_notifier(struct notifier_block *nb)
    +{
    + notifier_chain_unregister(&memory_chain, nb);
    +}
    +
    +/*
    + * register_memory - Setup a sysfs device for a memory block
    + */
    +int
    +register_memory(struct memory_block *memory, struct mem_section *section,
    + struct node *root)
    +{
    + int error;
    +
    + memory->sysdev.cls = &memory_sysdev_class;
    + memory->sysdev.id = __section_nr(section);
    +
    + error = sysdev_register(&memory->sysdev);
    +
    + if (root && !error)
    + error = sysfs_create_link(&root->sysdev.kobj,
    + &memory->sysdev.kobj,
    + kobject_name(&memory->sysdev.kobj));
    +
    + return error;
    +}
    +
    +void
    +unregister_memory(struct memory_block *memory, struct mem_section *section,
    + struct node *root)
    +{
    + BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
    + BUG_ON(memory->sysdev.id != __section_nr(section));
    +
    + sysdev_unregister(&memory->sysdev);
    + if (root)
    + sysfs_remove_link(&root->sysdev.kobj,
    + kobject_name(&memory->sysdev.kobj));
    +}
    +
    +/*
    + * use this as the physical section index that this memsection
    + * uses.
    + */
    +
    +static ssize_t show_mem_phys_index(struct sys_device *dev, char *buf)
    +{
    + struct memory_block *mem =
    + container_of(dev, struct memory_block, sysdev);
    + return sprintf(buf, "%08lx\n", mem->phys_index);
    +}
    +
    +/*
    + * online, offline, going offline, etc.
    + */
    +static ssize_t show_mem_state(struct sys_device *dev, char *buf)
    +{
    + struct memory_block *mem =
    + container_of(dev, struct memory_block, sysdev);
    + ssize_t len = 0;
    +
    + /*
    + * We can probably put these states in a nice little array
    + * so that they're not open-coded
    + */
    + switch (mem->state) {
    + case MEM_ONLINE:
    + len = sprintf(buf, "online\n");
    + break;
    + case MEM_OFFLINE:
    + len = sprintf(buf, "offline\n");
    + break;
    + case MEM_GOING_OFFLINE:
    + len = sprintf(buf, "going-offline\n");
    + break;
    + default:
    + len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
    + mem->state);
    + WARN_ON(1);
    + break;
    + }
    +
    + return len;
    +}
    +
    +static inline int memory_notify(unsigned long val, void *v)
    +{
    + return notifier_call_chain(&memory_chain, val, v);
    +}
    +
    +/*
    + * MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
    + * OK to have direct references to sparsemem variables in here.
    + */
    +static int
    +memory_block_action(struct memory_block *mem, unsigned long action)
    +{
    + int i;
    + unsigned long psection;
    + unsigned long start_pfn, start_paddr;
    + struct page *first_page;
    + int ret;
    + int old_state = mem->state;
    +
    + psection = mem->phys_index;
    + first_page = pfn_to_page(psection << PFN_SECTION_SHIFT);
    +
    + /*
    + * The probe routines leave the pages reserved, just
    + * as the bootmem code does. Make sure they're still
    + * that way.
    + */
    + if (action == MEM_ONLINE) {
    + for (i = 0; i < PAGES_PER_SECTION; i++) {
    + if (PageReserved(first_page+i))
    + continue;
    +
    + printk(KERN_WARNING "section number %ld page number %d "
    + "not reserved, was it already online? \n",
    + psection, i);
    + return -EBUSY;
    + }
    + }
    +
    + switch (action) {
    + case MEM_ONLINE:
    + start_pfn = page_to_pfn(first_page);
    + ret = online_pages(start_pfn, PAGES_PER_SECTION);
    + break;
    + case MEM_OFFLINE:
    + mem->state = MEM_GOING_OFFLINE;
    + memory_notify(MEM_GOING_OFFLINE, NULL);
    + start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
    + ret = remove_memory(start_paddr,
    + PAGES_PER_SECTION << PAGE_SHIFT);
    + if (ret) {
    + mem->state = old_state;
    + break;
    + }
    + memory_notify(MEM_MAPPING_INVALID, NULL);
    + break;
    + default:
    + printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
    + __FUNCTION__, mem, action, action);
    + WARN_ON(1);
    + ret = -EINVAL;
    + }
    + /*
    + * For now, only notify on successful memory operations
    + */
    + if (!ret)
    + memory_notify(action, NULL);
    +
    + return ret;
    +}
    +
    +static int memory_block_change_state(struct memory_block *mem,
    + unsigned long to_state, unsigned long from_state_req)
    +{
    + int ret = 0;
    + down(&mem->state_sem);
    +
    + if (mem->state != from_state_req) {
    + ret = -EINVAL;
    + goto out;
    + }
    +
    + ret = memory_block_action(mem, to_state);
    + if (!ret)
    + mem->state = to_state;
    +
    +out:
    + up(&mem->state_sem);
    + return ret;
    +}
    +
    +static ssize_t
    +store_mem_state(struct sys_device *dev, const char *buf, size_t count)
    +{
    + struct memory_block *mem;
    + unsigned int phys_section_nr;
    + int ret = -EINVAL;
    +
    + mem = container_of(dev, struct memory_block, sysdev);
    + phys_section_nr = mem->phys_index;
    +
    + if (!valid_section_nr(phys_section_nr))
    + goto out;
    +
    + if (!strncmp(buf, "online", min((int)count, 6)))
    + ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
    + else if(!strncmp(buf, "offline", min((int)count, 7)))
    + ret = memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
    +out:
    + if (ret)
    + return ret;
    + return count;
    +}
    +
    +/*
    + * phys_device is a bad name for this. What I really want
    + * is a way to differentiate between memory ranges that
    + * are part of physical devices that constitute
    + * a complete removable unit or fru.
    + * i.e. do these ranges belong to the same physical device,
    + * s.t. if I offline all of these sections I can then
    + * remove the physical device?
    + */
    +static ssize_t show_phys_device(struct sys_device *dev, char *buf)
    +{
    + struct memory_block *mem =
    + container_of(dev, struct memory_block, sysdev);
    + return sprintf(buf, "%d\n", mem->phys_device);
    +}
    +
    +SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
    +SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
    +SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
    +
    +#define mem_create_simple_file(mem, attr_name) \
    + sysdev_create_file(&mem->sysdev, &attr_##attr_name)
    +#define mem_remove_simple_file(mem, attr_name) \
    + sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
    +
    +/*
    + * Block size attribute stuff
    + */
    +static ssize_t
    +print_block_size(struct class *class, char *buf)
    +{
    + return sprintf(buf, "%lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
    +}
    +
    +static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
    +
    +static int block_size_init(void)
    +{
    + sysfs_create_file(&memory_sysdev_class.kset.kobj,
    + &class_attr_block_size_bytes.attr);
    + return 0;
    +}
    +
    +/*
    + * Some architectures will have custom drivers to do this, and
    + * will not need to do it from userspace. The fake hot-add code
    + * as well as ppc64 will do all of their discovery in userspace
    + * and will require this interface.
    + */
    +#ifdef CONFIG_ARCH_MEMORY_PROBE
    +static ssize_t
    +memory_probe_store(struct class *class, const char __user *buf, size_t count)
    +{
    + u64 phys_addr;
    + int ret;
    +
    + phys_addr = simple_strtoull(buf, NULL, 0);
    +
    + ret = add_memory(phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
    +
    + if (ret)
    + count = ret;
    +
    + return count;
    +}
    +static CLASS_ATTR(probe, 0700, NULL, memory_probe_store);
    +
    +static int memory_probe_init(void)
    +{
    + sysfs_create_file(&memory_sysdev_class.kset.kobj,
    + &class_attr_probe.attr);
    + return 0;
    +}
    +#else
    +#define memory_probe_init(...) do {} while (0)
    +#endif
    +
    +/*
    + * Note that phys_device is optional. It is here to allow for
    + * differentiation between which *physical* devices each
    + * section belongs to...
    + */
    +
    +int add_memory_block(unsigned long node_id, struct mem_section *section,
    + unsigned long state, int phys_device)
    +{
    + size_t size = sizeof(struct memory_block);
    + struct memory_block *mem = kmalloc(size, GFP_KERNEL);
    + int ret = 0;
    +
    + if (!mem)
    + return -ENOMEM;
    +
    + memset(mem, 0, size);
    +
    + mem->phys_index = __section_nr(section);
    + mem->state = state;
    + init_MUTEX(&mem->state_sem);
    + mem->phys_device = phys_device;
    +
    + ret = register_memory(mem, section, NULL);
    + if (!ret)
    + ret = mem_create_simple_file(mem, phys_index);
    + if (!ret)
    + ret = mem_create_simple_file(mem, state);
    + if (!ret)
    + ret = mem_create_simple_file(mem, phys_device);
    +
    + return ret;
    +}
    +
    +/*
    + * For now, we have a linear search to go find the appropriate
    + * memory_block corresponding to a particular phys_index. If
    + * this gets to be a real problem, we can always use a radix
    + * tree or something here.
    + *
    + * This could be made generic for all sysdev classes.
    + */
    +struct memory_block *find_memory_block(struct mem_section *section)
    +{
    + struct kobject *kobj;
    + struct sys_device *sysdev;
    + struct memory_block *mem;
    + char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
    +
    + /*
    + * This only works because we know that section == sysdev->id
    + * slightly redundant with sysdev_register()
    + */
    + sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
    +
    + kobj = kset_find_obj(&memory_sysdev_class.kset, name);
    + if (!kobj)
    + return NULL;
    +
    + sysdev = container_of(kobj, struct sys_device, kobj);
    + mem = container_of(sysdev, struct memory_block, sysdev);
    +
    + return mem;
    +}
    +
    +int remove_memory_block(unsigned long node_id, struct mem_section *section,
    + int phys_device)
    +{
    + struct memory_block *mem;
    +
    + mem = find_memory_block(section);
    + mem_remove_simple_file(mem, phys_index);
    + mem_remove_simple_file(mem, state);
    + mem_remove_simple_file(mem, phys_device);
    + unregister_memory(mem, section, NULL);
    +
    + return 0;
    +}
    +
    +/*
    + * need an interface for the VM to add new memory regions,
    + * but without onlining it.
    + */
    +int register_new_memory(struct mem_section *section)
    +{
    + return add_memory_block(0, section, MEM_OFFLINE, 0);
    +}
    +
    +int unregister_memory_section(struct mem_section *section)
    +{
    + if (!valid_section(section))
    + return -EINVAL;
    +
    + return remove_memory_block(0, section, 0);
    +}
    +
    +/*
    + * Initialize the sysfs support for memory devices...
    + */
    +int __init memory_dev_init(void)
    +{
    + unsigned int i;
    + int ret;
    +
    + memory_sysdev_class.kset.hotplug_ops = &memory_hotplug_ops;
    + ret = sysdev_class_register(&memory_sysdev_class);
    +
    + /*
    + * Create entries for memory sections that were found
    + * during boot and have been initialized
    + */
    + for (i = 0; i < NR_MEM_SECTIONS; i++) {
    + if (!valid_section_nr(i))
    + continue;
    + add_memory_block(0, __nr_to_section(i), MEM_ONLINE, 0);
    + }
    +
    + memory_probe_init();
    + block_size_init();
    +
    + return ret;
    +}
    diff -puN include/asm-i386/highmem.h~D0-sysfs-memory-class include/asm-i386/highmem.h
    diff -puN /dev/null include/linux/memory.h
    --- /dev/null 2005-03-30 22:36:15.000000000 -0800
    +++ memhotplug-dave/include/linux/memory.h 2005-08-12 07:43:48.000000000 -0700
    @@ -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 <linux/sysdev.h>
    +#include <linux/node.h>
    +#include <linux/compiler.h>
    +
    +#include <asm/semaphore.h>
    +
    +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<<PAGE_SHIFT)
    +
    +extern int invalidate_phys_mapping(unsigned long, unsigned long);
    +struct notifier_block;
    +
    +extern int register_memory_notifier(struct notifier_block *nb);
    +extern void unregister_memory_notifier(struct notifier_block *nb);
    +
    +extern struct sysdev_class memory_sysdev_class;
    +#endif /* CONFIG_MEMORY_HOTPLUG */
    +
    +#define hotplug_memory_notifier(fn, pri) { \
    + static struct notifier_block fn##_mem_nb = \
    + { .notifier_call = fn, .priority = pri }; \
    + register_memory_notifier(&fn##_mem_nb); \
    +}
    +
    +#endif /* _LINUX_MEMORY_H_ */
    diff -puN include/linux/memory_hotplug.h~D0-sysfs-memory-class include/linux/memory_hotplug.h
    --- memhotplug/include/linux/memory_hotplug.h~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/include/linux/memory_hotplug.h 2005-08-12 07:43:48.000000000 -0700
    @@ -3,6 +3,8 @@

    #include <linux/mmzone.h>
    #include <linux/spinlock.h>
    +#include <linux/mmzone.h>
    +#include <linux/notifier.h>

    #ifdef CONFIG_MEMORY_HOTPLUG
    /*
    @@ -46,6 +48,19 @@ static inline void zone_seqlock_init(str
    {
    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(str
    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 -puN mm/Kconfig~D0-sysfs-memory-class mm/Kconfig
    --- memhotplug/mm/Kconfig~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/mm/Kconfig 2005-08-12 07:43:48.000000000 -0700
    @@ -111,3 +111,11 @@ config SPARSEMEM_STATIC
    config SPARSEMEM_EXTREME
    def_bool y
    depends on SPARSEMEM && !SPARSEMEM_STATIC
    +
    +# eventually, we can have this option just 'select SPARSEMEM'
    +config MEMORY_HOTPLUG
    + bool "Allow for memory hot-add"
    + depends on SPARSEMEM && HOTPLUG && !SOFTWARE_SUSPEND
    +
    +comment "Memory hotplug is currently incompatible with Software Suspend"
    + depends on SPARSEMEM && HOTPLUG && SOFTWARE_SUSPEND
    diff -puN mm/Makefile~D0-sysfs-memory-class mm/Makefile
    --- memhotplug/mm/Makefile~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/mm/Makefile 2005-08-12 07:43:48.000000000 -0700
    @@ -18,5 +18,5 @@ obj-$(CONFIG_NUMA) += mempolicy.o
    obj-$(CONFIG_SPARSEMEM) += sparse.o
    obj-$(CONFIG_SHMEM) += shmem.o
    obj-$(CONFIG_TINY_SHMEM) += tiny-shmem.o
    -
    +obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
    obj-$(CONFIG_FS_XIP) += filemap_xip.o
    diff -puN /dev/null mm/memory_hotplug.c
    --- /dev/null 2005-03-30 22:36:15.000000000 -0800
    +++ memhotplug-dave/mm/memory_hotplug.c 2005-08-12 07:43:48.000000000 -0700
    @@ -0,0 +1,178 @@
    +/*
    + * linux/mm/memory_hotplug.c
    + *
    + * Copyright (C)
    + */
    +
    +#include <linux/config.h>
    +#include <linux/stddef.h>
    +#include <linux/mm.h>
    +#include <linux/swap.h>
    +#include <linux/interrupt.h>
    +#include <linux/pagemap.h>
    +#include <linux/bootmem.h>
    +#include <linux/compiler.h>
    +#include <linux/module.h>
    +#include <linux/pagevec.h>
    +#include <linux/slab.h>
    +#include <linux/sysctl.h>
    +#include <linux/cpu.h>
    +#include <linux/memory.h>
    +#include <linux/memory_hotplug.h>
    +#include <linux/highmem.h>
    +#include <linux/vmalloc.h>
    +
    +#include <asm/tlbflush.h>
    +
    +static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
    +{
    + struct page *page, *ret;
    + unsigned long memmap_size = sizeof(struct page) * nr_pages;
    +
    + page = alloc_pages(GFP_KERNEL, get_order(memmap_size));
    + if (page)
    + goto got_map_page;
    +
    + ret = vmalloc(memmap_size);
    + if (ret)
    + goto got_map_ptr;
    +
    + return NULL;
    +got_map_page:
    + ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
    +got_map_ptr:
    + memset(ret, 0, memmap_size);
    +
    + return ret;
    +}
    +
    +extern void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,
    + unsigned long size);
    +static void __add_zone(struct zone *zone, unsigned long phys_start_pfn)
    +{
    + struct pglist_data *pgdat = zone->zone_pgdat;
    + int nr_pages = PAGES_PER_SECTION;
    + int nid = pgdat->node_id;
    + int zone_type;
    +
    + zone_type = zone - pgdat->node_zones;
    + memmap_init_zone(nr_pages, nid, zone_type, phys_start_pfn);
    + zonetable_add(zone, nid, zone_type, phys_start_pfn, nr_pages);
    +}
    +
    +extern int sparse_add_one_section(struct zone *, unsigned long,
    + struct page *mem_map);
    +int __add_section(struct zone *zone, unsigned long phys_start_pfn)
    +{
    + struct pglist_data *pgdat = zone->zone_pgdat;
    + int nr_pages = PAGES_PER_SECTION;
    + struct page *memmap;
    + int ret;
    +
    + /*
    + * This can potentially allocate memory, and does its own
    + * internal locking.
    + */
    + sparse_index_init(pfn_to_section_nr(phys_start_pfn), pgdat->node_id);
    +
    + pgdat_resize_lock(pgdat, &flags);
    + memmap = __kmalloc_section_memmap(nr_pages);
    + ret = sparse_add_one_section(zone, phys_start_pfn, memmap);
    + pgdat_resize_unlock(pgdat, &flags);
    +
    + if (ret <= 0) {
    + /* the mem_map didn't get used */
    + if (memmap >= (struct page *)VMALLOC_START &&
    + memmap < (struct page *)VMALLOC_END)
    + vfree(memmap);
    + else
    + free_pages((unsigned long)memmap,
    + get_order(sizeof(struct page) * nr_pages));
    + }
    +
    + if (ret < 0)
    + return ret;
    +
    + __add_zone(zone, phys_start_pfn);
    + return register_new_memory(__pfn_to_section(phys_start_pfn));
    +}
    +
    +/*
    + * Reasonably generic function for adding memory. It is
    + * expected that archs that support memory hotplug will
    + * call this function after deciding the zone to which to
    + * add the new pages.
    + */
    +int __add_pages(struct zone *zone, unsigned long phys_start_pfn,
    + unsigned long nr_pages)
    +{
    + unsigned long i;
    + int err = 0;
    +
    + for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) {
    + err = __add_section(zone, phys_start_pfn + i);
    +
    + if (err)
    + break;
    + }
    +
    + return err;
    +}
    +
    +static void grow_zone_span(struct zone *zone,
    + unsigned long start_pfn, unsigned long end_pfn)
    +{
    + unsigned long old_zone_end_pfn;
    +
    + zone_span_writelock(zone);
    +
    + old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
    + if (start_pfn < zone->zone_start_pfn)
    + zone->zone_start_pfn = start_pfn;
    +
    + if (end_pfn > old_zone_end_pfn)
    + zone->spanned_pages = end_pfn - zone->zone_start_pfn;
    +
    + zone_span_writeunlock(zone);
    +}
    +
    +static void grow_pgdat_span(struct pglist_data *pgdat,
    + unsigned long start_pfn, unsigned long end_pfn)
    +{
    + unsigned long old_pgdat_end_pfn =
    + pgdat->node_start_pfn + pgdat->node_spanned_pages;
    +
    + if (start_pfn < pgdat->node_start_pfn)
    + pgdat->node_start_pfn = start_pfn;
    +
    + if (end_pfn > old_pgdat_end_pfn)
    + pgdat->node_spanned_pages = end_pfn - pgdat->node_spanned_pages;
    +}
    +
    +int online_pages(unsigned long pfn, unsigned long nr_pages)
    +{
    + unsigned long i;
    + unsigned long flags;
    + unsigned long onlined_pages = 0;
    + struct zone *zone;
    +
    + /*
    + * This doesn't need a lock to do pfn_to_page().
    + * The section can't be removed here because of the
    + * memory_block->state_sem.
    + */
    + zone = page_zone(pfn_to_page(pfn));
    + pgdat_resize_lock(zone->zone_pgdat, &flags);
    + grow_zone_span(zone, pfn, pfn + nr_pages);
    + grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages);
    + pgdat_resize_unlock(zone->zone_pgdat, &flags);
    +
    + for (i = 0; i < nr_pages; i++) {
    + struct page *page = pfn_to_page(pfn + i);
    + online_page(page);
    + onlined_pages++;
    + }
    + zone->present_pages += onlined_pages;
    +
    + return 0;
    +}
    diff -puN mm/page_alloc.c~D0-sysfs-memory-class mm/page_alloc.c
    --- memhotplug/mm/page_alloc.c~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/mm/page_alloc.c 2005-08-12 07:43:48.000000000 -0700
    @@ -1663,7 +1663,7 @@ static void __init calculate_zone_totalp
    * up by free_all_bootmem() once the early boot process is
    * done. Non-atomic initialization, single-pass.
    */
    -void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone,
    +void __devinit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
    unsigned long start_pfn)
    {
    struct page *page;
    @@ -2386,7 +2386,7 @@ static void setup_per_zone_lowmem_reserv
    * that the pages_{min,low,high} values for each zone are set correctly
    * with respect to min_free_kbytes.
    */
    -static void setup_per_zone_pages_min(void)
    +void setup_per_zone_pages_min(void)
    {
    unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
    unsigned long lowmem_pages = 0;
    diff -puN include/linux/mm.h~D0-sysfs-memory-class include/linux/mm.h
    --- memhotplug/include/linux/mm.h~D0-sysfs-memory-class 2005-08-12 07:43:48.000000000 -0700
    +++ memhotplug-dave/include/linux/mm.h 2005-08-12 07:43:48.000000000 -0700
    @@ -791,6 +791,7 @@ extern void free_area_init_node(int nid,
    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);
    diff -puN mm/sparse.c~D0-sysfs-memory-class mm/sparse.c
    _
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/
    \
     
     \ /
      Last update: 2005-08-12 16:53    [W:0.068 / U:1.792 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site