[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 <matthew.e.tolentino@intel.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 66d9c46..f12898d 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -7,6 +7,7 @@
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 --git a/drivers/base/init.c b/drivers/base/init.c
index 84e604e..c648914 100644
--- a/drivers/base/init.c
+++ b/drivers/base/init.c
@@ -9,6 +9,7 @@
#include <linux/device.h>
#include <linux/init.h>
+#include <linux/memory.h>
#include "base.h"
@@ -33,5 +34,6 @@
platform_bus_init();
system_bus_init();
cpu_dev_init();
+ memory_dev_init();
attribute_container_init();
}
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
new file mode 100644
index 0000000..785cb6e
--- /dev/null
+++ b/drivers/base/memory.c
@@ -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"
+
+static 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;
+
+static int register_memory_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_register(&memory_chain, nb);
+}
+
+static void unregister_memory_notifier(struct notifier_block *nb)
+{
+ notifier_chain_unregister(&memory_chain, nb);
+}
+
+/*
+ * register_memory - Setup a sysfs device for a memory block
+ */
+static 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;
+}
+
+static 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);
+}
+
+static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
+static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
+static 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...
+ */
+
+static 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.
+ */
+static 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 --git a/include/linux/memory.h b/include/linux/memory.h
new file mode 100644
index 0000000..0def328
--- /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 <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 --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 4b08bc9..01f03bc 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -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 @@
{
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 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 8a514ec..5c1fb0a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -840,6 +840,7 @@
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 --git a/mm/Kconfig b/mm/Kconfig
index f35a550..1a4473fc 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -112,6 +112,14 @@
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
+
# Heavily threaded applications may benefit from splitting the mm-wide
# page_table_lock, so that faults on different parts of the user address
# space can be handled with less contention: split it at this NR_CPUS.
diff --git a/mm/Makefile b/mm/Makefile
index 4cd69e3..2fa6d2c 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -18,5 +18,5 @@
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 --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
new file mode 100644
index 0000000..855e0fc
--- /dev/null
+++ b/mm/memory_hotplug.c
@@ -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);
+static 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 --git a/mm/page_alloc.c b/mm/page_alloc.c
index 817635f..183abf3 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1686,7 +1686,7 @@
* 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;
@@ -2407,7 +2407,7 @@
* 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;