[linux-2.6-block.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, 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;
}

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:
			printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
					__func__, mem, action, action);
			WARN_ON(1);
			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, 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, 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)
{
	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);

	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);

	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
	95	static ssize_t show_mem_phys_index(struct sys_device dev, char buf)
	96	{
	97	struct memory_block *mem =
	98	container_of(dev, struct memory_block, sysdev);
	99	return sprintf(buf, "%08lx\n", mem->phys_index);
	100	}
	101
	102	/*
	103	* online, offline, going offline, etc.
	104	*/
	105	static ssize_t show_mem_state(struct sys_device dev, char buf)
	106	{
	107	struct memory_block *mem =
	108	container_of(dev, struct memory_block, sysdev);
	109	ssize_t len = 0;
	110
	111	/*
	112	* We can probably put these states in a nice little array
	113	* so that they're not open-coded
	114	*/
	115	switch (mem->state) {
	116	case MEM_ONLINE:
	117	len = sprintf(buf, "online\n");
	118	break;
	119	case MEM_OFFLINE:
	120	len = sprintf(buf, "offline\n");
	121	break;
	122	case MEM_GOING_OFFLINE:
	123	len = sprintf(buf, "going-offline\n");
	124	break;
	125	default:
	126	len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
	127	mem->state);
	128	WARN_ON(1);
	129	break;
	130	}
	131
	132	return len;
	133	}
	134
7b78d335	135	int memory_notify(unsigned long val, void *v)
3947be19	136	{
e041c683	137	return blocking_notifier_call_chain(&memory_chain, val, v);
3947be19 DH	138	}
	139
	140	/*
	141	* MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
	142	* OK to have direct references to sparsemem variables in here.
	143	*/
	144	static int
	145	memory_block_action(struct memory_block *mem, unsigned long action)
	146	{
	147	int i;
	148	unsigned long psection;
	149	unsigned long start_pfn, start_paddr;
	150	struct page *first_page;
	151	int ret;
	152	int old_state = mem->state;
	153
	154	psection = mem->phys_index;
	155	first_page = pfn_to_page(psection << PFN_SECTION_SHIFT);
	156
	157	/*
	158	* The probe routines leave the pages reserved, just
	159	* as the bootmem code does. Make sure they're still
	160	* that way.
	161	*/
	162	if (action == MEM_ONLINE) {
	163	for (i = 0; i < PAGES_PER_SECTION; i++) {
	164	if (PageReserved(first_page+i))
	165	continue;
	166
	167	printk(KERN_WARNING "section number %ld page number %d "
	168	"not reserved, was it already online? \n",
	169	psection, i);
	170	return -EBUSY;
	171	}
	172	}
	173
	174	switch (action) {
	175	case MEM_ONLINE:
	176	start_pfn = page_to_pfn(first_page);
	177	ret = online_pages(start_pfn, PAGES_PER_SECTION);
	178	break;
	179	case MEM_OFFLINE:
	180	mem->state = MEM_GOING_OFFLINE;
3947be19 DH	181	start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
	182	ret = remove_memory(start_paddr,
	183	PAGES_PER_SECTION << PAGE_SHIFT);
	184	if (ret) {
	185	mem->state = old_state;
	186	break;
	187	}
3947be19 DH	188	break;
	189	default:
	190	printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
2b3a302a	191	__func__, mem, action, action);
3947be19 DH	192	WARN_ON(1);
	193	ret = -EINVAL;
	194	}
3947be19 DH	195
	196	return ret;
	197	}
	198
	199	static int memory_block_change_state(struct memory_block *mem,
	200	unsigned long to_state, unsigned long from_state_req)
	201	{
	202	int ret = 0;
da19cbcf	203	mutex_lock(&mem->state_mutex);
3947be19 DH	204
	205	if (mem->state != from_state_req) {
	206	ret = -EINVAL;
	207	goto out;
	208	}
	209
	210	ret = memory_block_action(mem, to_state);
	211	if (!ret)
	212	mem->state = to_state;
	213
	214	out:
da19cbcf	215	mutex_unlock(&mem->state_mutex);
3947be19 DH	216	return ret;
	217	}
	218
	219	static ssize_t
	220	store_mem_state(struct sys_device dev, const char buf, size_t count)
	221	{
	222	struct memory_block *mem;
	223	unsigned int phys_section_nr;
	224	int ret = -EINVAL;
	225
	226	mem = container_of(dev, struct memory_block, sysdev);
	227	phys_section_nr = mem->phys_index;
	228
540557b9	229	if (!present_section_nr(phys_section_nr))
3947be19 DH	230	goto out;
	231
	232	if (!strncmp(buf, "online", min((int)count, 6)))
	233	ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
	234	else if(!strncmp(buf, "offline", min((int)count, 7)))
	235	ret = memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
	236	out:
	237	if (ret)
	238	return ret;
	239	return count;
	240	}
	241
	242	/*
	243	* phys_device is a bad name for this. What I really want
	244	* is a way to differentiate between memory ranges that
	245	* are part of physical devices that constitute
	246	* a complete removable unit or fru.
	247	* i.e. do these ranges belong to the same physical device,
	248	* s.t. if I offline all of these sections I can then
	249	* remove the physical device?
	250	*/
	251	static ssize_t show_phys_device(struct sys_device dev, char buf)
	252	{
	253	struct memory_block *mem =
	254	container_of(dev, struct memory_block, sysdev);
	255	return sprintf(buf, "%d\n", mem->phys_device);
	256	}
	257
	258	static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
	259	static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
	260	static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
	261
	262	#define mem_create_simple_file(mem, attr_name) \
	263	sysdev_create_file(&mem->sysdev, &attr_##attr_name)
	264	#define mem_remove_simple_file(mem, attr_name) \
	265	sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
	266
	267	/*
	268	* Block size attribute stuff
	269	*/
	270	static ssize_t
	271	print_block_size(struct class class, char buf)
	272	{
	273	return sprintf(buf, "%lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
	274	}
	275
	276	static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
	277
	278	static int block_size_init(void)
	279	{
28ec24e2 AM	280	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
28ec24e2 AM	281	&class_attr_block_size_bytes.attr);
3947be19 DH	282	}
	283
	284	/*
	285	* Some architectures will have custom drivers to do this, and
	286	* will not need to do it from userspace. The fake hot-add code
	287	* as well as ppc64 will do all of their discovery in userspace
	288	* and will require this interface.
	289	*/
	290	#ifdef CONFIG_ARCH_MEMORY_PROBE
	291	static ssize_t
be7ee9b2	292	memory_probe_store(struct class class, const char buf, size_t count)
3947be19 DH	293	{
3947be19 DH	294	u64 phys_addr;
bc02af93	295	int nid;
3947be19 DH	296	int ret;
	297
	298	phys_addr = simple_strtoull(buf, NULL, 0);
	299
bc02af93 YG	300	nid = memory_add_physaddr_to_nid(phys_addr);
bc02af93 YG	301	ret = add_memory(nid, phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
3947be19 DH	302
	303	if (ret)
	304	count = ret;
	305
	306	return count;
	307	}
	308	static CLASS_ATTR(probe, 0700, NULL, memory_probe_store);
	309
	310	static int memory_probe_init(void)
	311	{
28ec24e2 AM	312	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
28ec24e2 AM	313	&class_attr_probe.attr);
3947be19 DH	314	}
3947be19 DH	315	#else
28ec24e2 AM	316	static inline int memory_probe_init(void)
	317	{
	318	return 0;
	319	}
3947be19 DH	320	#endif
	321
	322	/*
	323	* Note that phys_device is optional. It is here to allow for
	324	* differentiation between which physical devices each
	325	* section belongs to...
	326	*/
	327
	328	static int add_memory_block(unsigned long node_id, struct mem_section *section,
	329	unsigned long state, int phys_device)
	330	{
0b0acbec	331	struct memory_block mem = kzalloc(sizeof(mem), GFP_KERNEL);
3947be19 DH	332	int ret = 0;
	333
	334	if (!mem)
	335	return -ENOMEM;
	336
3947be19 DH	337	mem->phys_index = __section_nr(section);
3947be19 DH	338	mem->state = state;
da19cbcf	339	mutex_init(&mem->state_mutex);
3947be19 DH	340	mem->phys_device = phys_device;
3947be19 DH	341
00a41db5	342	ret = register_memory(mem, section);
3947be19 DH	343	if (!ret)
	344	ret = mem_create_simple_file(mem, phys_index);
	345	if (!ret)
	346	ret = mem_create_simple_file(mem, state);
	347	if (!ret)
	348	ret = mem_create_simple_file(mem, phys_device);
	349
	350	return ret;
	351	}
	352
	353	/*
	354	* For now, we have a linear search to go find the appropriate
	355	* memory_block corresponding to a particular phys_index. If
	356	* this gets to be a real problem, we can always use a radix
	357	* tree or something here.
	358	*
	359	* This could be made generic for all sysdev classes.
	360	*/
	361	static struct memory_block find_memory_block(struct mem_section section)
	362	{
	363	struct kobject *kobj;
	364	struct sys_device *sysdev;
	365	struct memory_block *mem;
	366	char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
	367
	368	/*
	369	* This only works because we know that section == sysdev->id
	370	* slightly redundant with sysdev_register()
	371	*/
	372	sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
	373
	374	kobj = kset_find_obj(&memory_sysdev_class.kset, name);
	375	if (!kobj)
	376	return NULL;
	377
	378	sysdev = container_of(kobj, struct sys_device, kobj);
	379	mem = container_of(sysdev, struct memory_block, sysdev);
	380
	381	return mem;
	382	}
	383
	384	int remove_memory_block(unsigned long node_id, struct mem_section *section,
	385	int phys_device)
	386	{
	387	struct memory_block *mem;
	388
	389	mem = find_memory_block(section);
	390	mem_remove_simple_file(mem, phys_index);
	391	mem_remove_simple_file(mem, state);
	392	mem_remove_simple_file(mem, phys_device);
00a41db5	393	unregister_memory(mem, section);
3947be19 DH	394
	395	return 0;
	396	}
	397
	398	/*
	399	* need an interface for the VM to add new memory regions,
	400	* but without onlining it.
	401	*/
	402	int register_new_memory(struct mem_section *section)
	403	{
	404	return add_memory_block(0, section, MEM_OFFLINE, 0);
	405	}
	406
	407	int unregister_memory_section(struct mem_section *section)
	408	{
540557b9	409	if (!present_section(section))
3947be19 DH	410	return -EINVAL;
	411
	412	return remove_memory_block(0, section, 0);
	413	}
	414
	415	/*
	416	* Initialize the sysfs support for memory devices...
	417	*/
	418	int __init memory_dev_init(void)
	419	{
	420	unsigned int i;
	421	int ret;
28ec24e2	422	int err;
3947be19	423
312c004d	424	memory_sysdev_class.kset.uevent_ops = &memory_uevent_ops;
3947be19	425	ret = sysdev_class_register(&memory_sysdev_class);
28ec24e2 AM	426	if (ret)
28ec24e2 AM	427	goto out;
3947be19 DH	428
	429	/*
	430	* Create entries for memory sections that were found
	431	* during boot and have been initialized
	432	*/
	433	for (i = 0; i < NR_MEM_SECTIONS; i++) {
540557b9	434	if (!present_section_nr(i))
3947be19	435	continue;
28ec24e2 AM	436	err = add_memory_block(0, __nr_to_section(i), MEM_ONLINE, 0);
	437	if (!ret)
	438	ret = err;
3947be19 DH	439	}
3947be19 DH	440
28ec24e2 AM	441	err = memory_probe_init();
	442	if (!ret)
	443	ret = err;
	444	err = block_size_init();
	445	if (!ret)
	446	ret = err;
	447	out:
	448	if (ret)
2b3a302a	449	printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
3947be19 DH	450	return ret;
3947be19 DH	451	}