[deliverable/linux.git] / drivers / base / memory.c

/*
 * 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/topology.h>
#include <linux/capability.h>
#include <linux/device.h>
#include <linux/memory.h>
#include <linux/kobject.h>
#include <linux/memory_hotplug.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>

#define MEMORY_CLASS_NAME	"memory"

static struct sysdev_class memory_sysdev_class = {
	.name = MEMORY_CLASS_NAME,
};

static const char *memory_uevent_name(struct kset *kset, struct kobject *kobj)
{
	return MEMORY_CLASS_NAME;
}

static int memory_uevent(struct kset *kset, struct kobject *obj, struct kobj_uevent_env *env)
{
	int retval = 0;

	return retval;
}

static struct kset_uevent_ops memory_uevent_ops = {
	.name		= memory_uevent_name,
	.uevent		= memory_uevent,
};

static BLOCKING_NOTIFIER_HEAD(memory_chain);

int register_memory_notifier(struct notifier_block *nb)
{
        return blocking_notifier_chain_register(&memory_chain, nb);
}
EXPORT_SYMBOL(register_memory_notifier);

void unregister_memory_notifier(struct notifier_block *nb)
{
        blocking_notifier_chain_unregister(&memory_chain, nb);
}
EXPORT_SYMBOL(unregister_memory_notifier);

/*
 * register_memory - Setup a sysfs device for a memory block
 */
static
int register_memory(struct memory_block *memory, struct mem_section *section)
{
	int error;

	memory->sysdev.cls = &memory_sysdev_class;
	memory->sysdev.id = __section_nr(section);

	error = sysdev_register(&memory->sysdev);
	return error;
}

static void
unregister_memory(struct memory_block *memory, struct mem_section *section)
{
	BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
	BUG_ON(memory->sysdev.id != __section_nr(section));

	/* drop the ref. we got in remove_memory_block() */
	kobject_put(&memory->sysdev.kobj);
	sysdev_unregister(&memory->sysdev);
}

/*
 * use this as the physical section index that this memsection
 * uses.
 */

static ssize_t show_mem_phys_index(struct sys_device *dev,
			struct sysdev_attribute *attr, char *buf)
{
	struct memory_block *mem =
		container_of(dev, struct memory_block, sysdev);
	return sprintf(buf, "%08lx\n", mem->phys_index);
}

/*
 * Show whether the section of memory is likely to be hot-removable
 */
static ssize_t show_mem_removable(struct sys_device *dev,
			struct sysdev_attribute *attr, char *buf)
{
	unsigned long start_pfn;
	int ret;
	struct memory_block *mem =
		container_of(dev, struct memory_block, sysdev);

	start_pfn = section_nr_to_pfn(mem->phys_index);
	ret = is_mem_section_removable(start_pfn, PAGES_PER_SECTION);
	return sprintf(buf, "%d\n", ret);
}

/*
 * online, offline, going offline, etc.
 */
static ssize_t show_mem_state(struct sys_device *dev,
			struct sysdev_attribute *attr, 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;
}

int memory_notify(unsigned long val, void *v)
{
	return blocking_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;
			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;
			}
			break;
		default:
			WARN(1, KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
					__func__, mem, action, action);
			ret = -EINVAL;
	}

	return ret;
}

static int memory_block_change_state(struct memory_block *mem,
		unsigned long to_state, unsigned long from_state_req)
{
	int ret = 0;
	mutex_lock(&mem->state_mutex);

	if (mem->state != from_state_req) {
		ret = -EINVAL;
		goto out;
	}

	ret = memory_block_action(mem, to_state);
	if (!ret)
		mem->state = to_state;

out:
	mutex_unlock(&mem->state_mutex);
	return ret;
}

static ssize_t
store_mem_state(struct sys_device *dev,
		struct sysdev_attribute *attr, 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 (!present_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,
				struct sysdev_attribute *attr, 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);
static SYSDEV_ATTR(removable, 0444, show_mem_removable, 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)
{
	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
				&class_attr_block_size_bytes.attr);
}

/*
 * 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 *buf, size_t count)
{
	u64 phys_addr;
	int nid;
	int ret;

	phys_addr = simple_strtoull(buf, NULL, 0);

	nid = memory_add_physaddr_to_nid(phys_addr);
	ret = add_memory(nid, 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)
{
	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
				&class_attr_probe.attr);
}
#else
static inline int memory_probe_init(void)
{
	return 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)
{
	struct memory_block *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
	int ret = 0;

	if (!mem)
		return -ENOMEM;

	mem->phys_index = __section_nr(section);
	mem->state = state;
	mutex_init(&mem->state_mutex);
	mem->phys_device = phys_device;

	ret = register_memory(mem, section);
	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);
	if (!ret)
		ret = mem_create_simple_file(mem, removable);

	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);
	mem_remove_simple_file(mem, removable);
	unregister_memory(mem, section);

	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 (!present_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;
	int err;

	memory_sysdev_class.kset.uevent_ops = &memory_uevent_ops;
	ret = sysdev_class_register(&memory_sysdev_class);
	if (ret)
		goto out;

	/*
	 * Create entries for memory sections that were found
	 * during boot and have been initialized
	 */
	for (i = 0; i < NR_MEM_SECTIONS; i++) {
		if (!present_section_nr(i))
			continue;
		err = add_memory_block(0, __nr_to_section(i), MEM_ONLINE, 0);
		if (!ret)
			ret = err;
	}

	err = memory_probe_init();
	if (!ret)
		ret = err;
	err = block_size_init();
	if (!ret)
		ret = err;
out:
	if (ret)
		printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
	return ret;
}
Commit	Line	Data
3947be19 DH	1	/*
	2	* drivers/base/memory.c - basic Memory class support
	3	*
	4	* Written by Matt Tolentino <matthew.e.tolentino@intel.com>
	5	* Dave Hansen <haveblue@us.ibm.com>
	6	*
	7	* This file provides the necessary infrastructure to represent
	8	* a SPARSEMEM-memory-model system's physical memory in /sysfs.
	9	* All arch-independent code that assumes MEMORY_HOTPLUG requires
	10	* SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
	11	*/
	12
	13	#include <linux/sysdev.h>
	14	#include <linux/module.h>
	15	#include <linux/init.h>
3947be19	16	#include <linux/topology.h>
c59ede7b	17	#include <linux/capability.h>
3947be19 DH	18	#include <linux/device.h>
	19	#include <linux/memory.h>
	20	#include <linux/kobject.h>
	21	#include <linux/memory_hotplug.h>
	22	#include <linux/mm.h>
da19cbcf	23	#include <linux/mutex.h>
3947be19 DH	24	#include <asm/atomic.h>
	25	#include <asm/uaccess.h>
	26
	27	#define MEMORY_CLASS_NAME "memory"
	28
	29	static struct sysdev_class memory_sysdev_class = {
af5ca3f4	30	.name = MEMORY_CLASS_NAME,
3947be19	31	};
3947be19	32
312c004d	33	static const char memory_uevent_name(struct kset kset, struct kobject *kobj)
3947be19 DH	34	{
	35	return MEMORY_CLASS_NAME;
	36	}
	37
9ec0fd4e	38	static int memory_uevent(struct kset kset, struct kobject obj, struct kobj_uevent_env *env)
3947be19 DH	39	{
	40	int retval = 0;
	41
	42	return retval;
	43	}
	44
312c004d KS	45	static struct kset_uevent_ops memory_uevent_ops = {
	46	.name = memory_uevent_name,
	47	.uevent = memory_uevent,
3947be19 DH	48	};
3947be19 DH	49
e041c683	50	static BLOCKING_NOTIFIER_HEAD(memory_chain);
3947be19	51
98a38ebd	52	int register_memory_notifier(struct notifier_block *nb)
3947be19	53	{
e041c683	54	return blocking_notifier_chain_register(&memory_chain, nb);
3947be19	55	}
3c82c30c	56	EXPORT_SYMBOL(register_memory_notifier);
3947be19	57
98a38ebd	58	void unregister_memory_notifier(struct notifier_block *nb)
3947be19	59	{
e041c683	60	blocking_notifier_chain_unregister(&memory_chain, nb);
3947be19	61	}
3c82c30c	62	EXPORT_SYMBOL(unregister_memory_notifier);
3947be19 DH	63
	64	/*
	65	* register_memory - Setup a sysfs device for a memory block
	66	*/
00a41db5 BP	67	static
00a41db5 BP	68	int register_memory(struct memory_block memory, struct mem_section section)
3947be19 DH	69	{
	70	int error;
	71
	72	memory->sysdev.cls = &memory_sysdev_class;
	73	memory->sysdev.id = __section_nr(section);
	74
	75	error = sysdev_register(&memory->sysdev);
3947be19 DH	76	return error;
	77	}
	78
	79	static void
00a41db5	80	unregister_memory(struct memory_block memory, struct mem_section section)
3947be19 DH	81	{
	82	BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
	83	BUG_ON(memory->sysdev.id != __section_nr(section));
	84
00a41db5 BP	85	/* drop the ref. we got in remove_memory_block() */
00a41db5 BP	86	kobject_put(&memory->sysdev.kobj);
3947be19	87	sysdev_unregister(&memory->sysdev);
3947be19 DH	88	}
	89
	90	/*
	91	* use this as the physical section index that this memsection
	92	* uses.
	93	*/
	94
4a0b2b4d AK	95	static ssize_t show_mem_phys_index(struct sys_device *dev,
4a0b2b4d AK	96	struct sysdev_attribute attr, char buf)
3947be19 DH	97	{
	98	struct memory_block *mem =
	99	container_of(dev, struct memory_block, sysdev);
	100	return sprintf(buf, "%08lx\n", mem->phys_index);
	101	}
	102
5c755e9f BP	103	/*
	104	* Show whether the section of memory is likely to be hot-removable
	105	*/
1f07be1c SR	106	static ssize_t show_mem_removable(struct sys_device *dev,
1f07be1c SR	107	struct sysdev_attribute attr, char buf)
5c755e9f BP	108	{
	109	unsigned long start_pfn;
	110	int ret;
	111	struct memory_block *mem =
	112	container_of(dev, struct memory_block, sysdev);
	113
	114	start_pfn = section_nr_to_pfn(mem->phys_index);
	115	ret = is_mem_section_removable(start_pfn, PAGES_PER_SECTION);
	116	return sprintf(buf, "%d\n", ret);
	117	}
	118
3947be19 DH	119	/*
	120	* online, offline, going offline, etc.
	121	*/
4a0b2b4d AK	122	static ssize_t show_mem_state(struct sys_device *dev,
4a0b2b4d AK	123	struct sysdev_attribute attr, char buf)
3947be19 DH	124	{
	125	struct memory_block *mem =
	126	container_of(dev, struct memory_block, sysdev);
	127	ssize_t len = 0;
	128
	129	/*
	130	* We can probably put these states in a nice little array
	131	* so that they're not open-coded
	132	*/
	133	switch (mem->state) {
	134	case MEM_ONLINE:
	135	len = sprintf(buf, "online\n");
	136	break;
	137	case MEM_OFFLINE:
	138	len = sprintf(buf, "offline\n");
	139	break;
	140	case MEM_GOING_OFFLINE:
	141	len = sprintf(buf, "going-offline\n");
	142	break;
	143	default:
	144	len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
	145	mem->state);
	146	WARN_ON(1);
	147	break;
	148	}
	149
	150	return len;
	151	}
	152
7b78d335	153	int memory_notify(unsigned long val, void *v)
3947be19	154	{
e041c683	155	return blocking_notifier_call_chain(&memory_chain, val, v);
3947be19 DH	156	}
	157
	158	/*
	159	* MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
	160	* OK to have direct references to sparsemem variables in here.
	161	*/
	162	static int
	163	memory_block_action(struct memory_block *mem, unsigned long action)
	164	{
	165	int i;
	166	unsigned long psection;
	167	unsigned long start_pfn, start_paddr;
	168	struct page *first_page;
	169	int ret;
	170	int old_state = mem->state;
	171
	172	psection = mem->phys_index;
	173	first_page = pfn_to_page(psection << PFN_SECTION_SHIFT);
	174
	175	/*
	176	* The probe routines leave the pages reserved, just
	177	* as the bootmem code does. Make sure they're still
	178	* that way.
	179	*/
	180	if (action == MEM_ONLINE) {
	181	for (i = 0; i < PAGES_PER_SECTION; i++) {
	182	if (PageReserved(first_page+i))
	183	continue;
	184
	185	printk(KERN_WARNING "section number %ld page number %d "
	186	"not reserved, was it already online? \n",
	187	psection, i);
	188	return -EBUSY;
	189	}
	190	}
	191
	192	switch (action) {
	193	case MEM_ONLINE:
	194	start_pfn = page_to_pfn(first_page);
	195	ret = online_pages(start_pfn, PAGES_PER_SECTION);
	196	break;
	197	case MEM_OFFLINE:
	198	mem->state = MEM_GOING_OFFLINE;
3947be19 DH	199	start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
	200	ret = remove_memory(start_paddr,
	201	PAGES_PER_SECTION << PAGE_SHIFT);
	202	if (ret) {
	203	mem->state = old_state;
	204	break;
	205	}
3947be19 DH	206	break;
3947be19 DH	207	default:
f810a5cf	208	WARN(1, KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
2b3a302a	209	__func__, mem, action, action);
3947be19 DH	210	ret = -EINVAL;
3947be19 DH	211	}
3947be19 DH	212
	213	return ret;
	214	}
	215
	216	static int memory_block_change_state(struct memory_block *mem,
	217	unsigned long to_state, unsigned long from_state_req)
	218	{
	219	int ret = 0;
da19cbcf	220	mutex_lock(&mem->state_mutex);
3947be19 DH	221
	222	if (mem->state != from_state_req) {
	223	ret = -EINVAL;
	224	goto out;
	225	}
	226
	227	ret = memory_block_action(mem, to_state);
	228	if (!ret)
	229	mem->state = to_state;
	230
	231	out:
da19cbcf	232	mutex_unlock(&mem->state_mutex);
3947be19 DH	233	return ret;
	234	}
	235
	236	static ssize_t
4a0b2b4d AK	237	store_mem_state(struct sys_device *dev,
4a0b2b4d AK	238	struct sysdev_attribute attr, const char buf, size_t count)
3947be19 DH	239	{
	240	struct memory_block *mem;
	241	unsigned int phys_section_nr;
	242	int ret = -EINVAL;
	243
	244	mem = container_of(dev, struct memory_block, sysdev);
	245	phys_section_nr = mem->phys_index;
	246
540557b9	247	if (!present_section_nr(phys_section_nr))
3947be19 DH	248	goto out;
	249
	250	if (!strncmp(buf, "online", min((int)count, 6)))
	251	ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
	252	else if(!strncmp(buf, "offline", min((int)count, 7)))
	253	ret = memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
	254	out:
	255	if (ret)
	256	return ret;
	257	return count;
	258	}
	259
	260	/*
	261	* phys_device is a bad name for this. What I really want
	262	* is a way to differentiate between memory ranges that
	263	* are part of physical devices that constitute
	264	* a complete removable unit or fru.
	265	* i.e. do these ranges belong to the same physical device,
	266	* s.t. if I offline all of these sections I can then
	267	* remove the physical device?
	268	*/
4a0b2b4d AK	269	static ssize_t show_phys_device(struct sys_device *dev,
4a0b2b4d AK	270	struct sysdev_attribute attr, char buf)
3947be19 DH	271	{
	272	struct memory_block *mem =
	273	container_of(dev, struct memory_block, sysdev);
	274	return sprintf(buf, "%d\n", mem->phys_device);
	275	}
	276
	277	static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
	278	static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
	279	static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
5c755e9f	280	static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL);
3947be19 DH	281
	282	#define mem_create_simple_file(mem, attr_name) \
	283	sysdev_create_file(&mem->sysdev, &attr_##attr_name)
	284	#define mem_remove_simple_file(mem, attr_name) \
	285	sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
	286
	287	/*
	288	* Block size attribute stuff
	289	*/
	290	static ssize_t
	291	print_block_size(struct class class, char buf)
	292	{
	293	return sprintf(buf, "%lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
	294	}
	295
	296	static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
	297
	298	static int block_size_init(void)
	299	{
28ec24e2 AM	300	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
28ec24e2 AM	301	&class_attr_block_size_bytes.attr);
3947be19 DH	302	}
	303
	304	/*
	305	* Some architectures will have custom drivers to do this, and
	306	* will not need to do it from userspace. The fake hot-add code
	307	* as well as ppc64 will do all of their discovery in userspace
	308	* and will require this interface.
	309	*/
	310	#ifdef CONFIG_ARCH_MEMORY_PROBE
	311	static ssize_t
be7ee9b2	312	memory_probe_store(struct class class, const char buf, size_t count)
3947be19 DH	313	{
3947be19 DH	314	u64 phys_addr;
bc02af93	315	int nid;
3947be19 DH	316	int ret;
	317
	318	phys_addr = simple_strtoull(buf, NULL, 0);
	319
bc02af93 YG	320	nid = memory_add_physaddr_to_nid(phys_addr);
bc02af93 YG	321	ret = add_memory(nid, phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
3947be19 DH	322
	323	if (ret)
	324	count = ret;
	325
	326	return count;
	327	}
	328	static CLASS_ATTR(probe, 0700, NULL, memory_probe_store);
	329
	330	static int memory_probe_init(void)
	331	{
28ec24e2 AM	332	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
28ec24e2 AM	333	&class_attr_probe.attr);
3947be19 DH	334	}
3947be19 DH	335	#else
28ec24e2 AM	336	static inline int memory_probe_init(void)
	337	{
	338	return 0;
	339	}
3947be19 DH	340	#endif
	341
	342	/*
	343	* Note that phys_device is optional. It is here to allow for
	344	* differentiation between which physical devices each
	345	* section belongs to...
	346	*/
	347
	348	static int add_memory_block(unsigned long node_id, struct mem_section *section,
	349	unsigned long state, int phys_device)
	350	{
0b0acbec	351	struct memory_block mem = kzalloc(sizeof(mem), GFP_KERNEL);
3947be19 DH	352	int ret = 0;
	353
	354	if (!mem)
	355	return -ENOMEM;
	356
3947be19 DH	357	mem->phys_index = __section_nr(section);
3947be19 DH	358	mem->state = state;
da19cbcf	359	mutex_init(&mem->state_mutex);
3947be19 DH	360	mem->phys_device = phys_device;
3947be19 DH	361
00a41db5	362	ret = register_memory(mem, section);
3947be19 DH	363	if (!ret)
	364	ret = mem_create_simple_file(mem, phys_index);
	365	if (!ret)
	366	ret = mem_create_simple_file(mem, state);
	367	if (!ret)
	368	ret = mem_create_simple_file(mem, phys_device);
5c755e9f BP	369	if (!ret)
5c755e9f BP	370	ret = mem_create_simple_file(mem, removable);
3947be19 DH	371
	372	return ret;
	373	}
	374
	375	/*
	376	* For now, we have a linear search to go find the appropriate
	377	* memory_block corresponding to a particular phys_index. If
	378	* this gets to be a real problem, we can always use a radix
	379	* tree or something here.
	380	*
	381	* This could be made generic for all sysdev classes.
	382	*/
	383	static struct memory_block find_memory_block(struct mem_section section)
	384	{
	385	struct kobject *kobj;
	386	struct sys_device *sysdev;
	387	struct memory_block *mem;
	388	char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
	389
	390	/*
	391	* This only works because we know that section == sysdev->id
	392	* slightly redundant with sysdev_register()
	393	*/
	394	sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
	395
	396	kobj = kset_find_obj(&memory_sysdev_class.kset, name);
	397	if (!kobj)
	398	return NULL;
	399
	400	sysdev = container_of(kobj, struct sys_device, kobj);
	401	mem = container_of(sysdev, struct memory_block, sysdev);
	402
	403	return mem;
	404	}
	405
	406	int remove_memory_block(unsigned long node_id, struct mem_section *section,
	407	int phys_device)
	408	{
	409	struct memory_block *mem;
	410
	411	mem = find_memory_block(section);
	412	mem_remove_simple_file(mem, phys_index);
	413	mem_remove_simple_file(mem, state);
	414	mem_remove_simple_file(mem, phys_device);
5c755e9f	415	mem_remove_simple_file(mem, removable);
00a41db5	416	unregister_memory(mem, section);
3947be19 DH	417
	418	return 0;
	419	}
	420
	421	/*
	422	* need an interface for the VM to add new memory regions,
	423	* but without onlining it.
	424	*/
	425	int register_new_memory(struct mem_section *section)
	426	{
	427	return add_memory_block(0, section, MEM_OFFLINE, 0);
	428	}
	429
	430	int unregister_memory_section(struct mem_section *section)
	431	{
540557b9	432	if (!present_section(section))
3947be19 DH	433	return -EINVAL;
	434
	435	return remove_memory_block(0, section, 0);
	436	}
	437
	438	/*
	439	* Initialize the sysfs support for memory devices...
	440	*/
	441	int __init memory_dev_init(void)
	442	{
	443	unsigned int i;
	444	int ret;
28ec24e2	445	int err;
3947be19	446
312c004d	447	memory_sysdev_class.kset.uevent_ops = &memory_uevent_ops;
3947be19	448	ret = sysdev_class_register(&memory_sysdev_class);
28ec24e2 AM	449	if (ret)
28ec24e2 AM	450	goto out;
3947be19 DH	451
	452	/*
	453	* Create entries for memory sections that were found
	454	* during boot and have been initialized
	455	*/
	456	for (i = 0; i < NR_MEM_SECTIONS; i++) {
540557b9	457	if (!present_section_nr(i))
3947be19	458	continue;
28ec24e2 AM	459	err = add_memory_block(0, __nr_to_section(i), MEM_ONLINE, 0);
	460	if (!ret)
	461	ret = err;
3947be19 DH	462	}
3947be19 DH	463
28ec24e2 AM	464	err = memory_probe_init();
	465	if (!ret)
	466	ret = err;
	467	err = block_size_init();
	468	if (!ret)
	469	ret = err;
	470	out:
	471	if (ret)
2b3a302a	472	printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
3947be19 DH	473	return ret;
3947be19 DH	474	}