[linux-2.6-block.git] / drivers / scsi / raid_class.c

/*
 * raid_class.c - implementation of a simple raid visualisation class
 *
 * Copyright (c) 2005 - James Bottomley <James.Bottomley@steeleye.com>
 *
 * This file is licensed under GPLv2
 *
 * This class is designed to allow raid attributes to be visualised and
 * manipulated in a form independent of the underlying raid.  Ultimately this
 * should work for both hardware and software raids.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/raid_class.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>

#define RAID_NUM_ATTRS	3

struct raid_internal {
	struct raid_template r;
	struct raid_function_template *f;
	/* The actual attributes */
	struct device_attribute private_attrs[RAID_NUM_ATTRS];
	/* The array of null terminated pointers to attributes 
	 * needed by scsi_sysfs.c */
	struct device_attribute *attrs[RAID_NUM_ATTRS + 1];
};

struct raid_component {
	struct list_head node;
	struct device dev;
	int num;
};

#define to_raid_internal(tmpl)	container_of(tmpl, struct raid_internal, r)

#define tc_to_raid_internal(tcont) ({					\
	struct raid_template *r =					\
		container_of(tcont, struct raid_template, raid_attrs);	\
	to_raid_internal(r);						\
})

#define ac_to_raid_internal(acont) ({					\
	struct transport_container *tc =				\
		container_of(acont, struct transport_container, ac);	\
	tc_to_raid_internal(tc);					\
})

#define device_to_raid_internal(dev) ({				\
	struct attribute_container *ac =				\
		attribute_container_classdev_to_container(dev);	\
	ac_to_raid_internal(ac);					\
})
	

static int raid_match(struct attribute_container *cont, struct device *dev)
{
	/* We have to look for every subsystem that could house
	 * emulated RAID devices, so start with SCSI */
	struct raid_internal *i = ac_to_raid_internal(cont);

	if (scsi_is_sdev_device(dev)) {
		struct scsi_device *sdev = to_scsi_device(dev);

		if (i->f->cookie != sdev->host->hostt)
			return 0;

		return i->f->is_raid(dev);
	}
	/* FIXME: look at other subsystems too */
	return 0;
}

static int raid_setup(struct transport_container *tc, struct device *dev,
		       struct device *cdev)
{
	struct raid_data *rd;

	BUG_ON(dev_get_drvdata(cdev));

	rd = kzalloc(sizeof(*rd), GFP_KERNEL);
	if (!rd)
		return -ENOMEM;

	INIT_LIST_HEAD(&rd->component_list);
	dev_set_drvdata(cdev, rd);
		
	return 0;
}

static int raid_remove(struct transport_container *tc, struct device *dev,
		       struct device *cdev)
{
	struct raid_data *rd = dev_get_drvdata(cdev);
	struct raid_component *rc, *next;
	dev_printk(KERN_ERR, dev, "RAID REMOVE\n");
	dev_set_drvdata(cdev, NULL);
	list_for_each_entry_safe(rc, next, &rd->component_list, node) {
		list_del(&rc->node);
		dev_printk(KERN_ERR, rc->dev.parent, "RAID COMPONENT REMOVE\n");
		device_unregister(&rc->dev);
	}
	dev_printk(KERN_ERR, dev, "RAID REMOVE DONE\n");
	kfree(rd);
	return 0;
}

static DECLARE_TRANSPORT_CLASS(raid_class,
			       "raid_devices",
			       raid_setup,
			       raid_remove,
			       NULL);

static const struct {
	enum raid_state	value;
	char		*name;
} raid_states[] = {
	{ RAID_STATE_UNKNOWN, "unknown" },
	{ RAID_STATE_ACTIVE, "active" },
	{ RAID_STATE_DEGRADED, "degraded" },
	{ RAID_STATE_RESYNCING, "resyncing" },
	{ RAID_STATE_OFFLINE, "offline" },
};

static const char *raid_state_name(enum raid_state state)
{
	int i;
	char *name = NULL;

	for (i = 0; i < ARRAY_SIZE(raid_states); i++) {
		if (raid_states[i].value == state) {
			name = raid_states[i].name;
			break;
		}
	}
	return name;
}

static struct {
	enum raid_level value;
	char *name;
} raid_levels[] = {
	{ RAID_LEVEL_UNKNOWN, "unknown" },
	{ RAID_LEVEL_LINEAR, "linear" },
	{ RAID_LEVEL_0, "raid0" },
	{ RAID_LEVEL_1, "raid1" },
	{ RAID_LEVEL_10, "raid10" },
	{ RAID_LEVEL_3, "raid3" },
	{ RAID_LEVEL_4, "raid4" },
	{ RAID_LEVEL_5, "raid5" },
	{ RAID_LEVEL_50, "raid50" },
	{ RAID_LEVEL_6, "raid6" },
};

static const char *raid_level_name(enum raid_level level)
{
	int i;
	char *name = NULL;

	for (i = 0; i < ARRAY_SIZE(raid_levels); i++) {
		if (raid_levels[i].value == level) {
			name = raid_levels[i].name;
			break;
		}
	}
	return name;
}

#define raid_attr_show_internal(attr, fmt, var, code)			\
static ssize_t raid_show_##attr(struct device *dev, 			\
				struct device_attribute *attr, 		\
				char *buf)				\
{									\
	struct raid_data *rd = dev_get_drvdata(dev);			\
	code								\
	return snprintf(buf, 20, #fmt "\n", var);			\
}

#define raid_attr_ro_states(attr, states, code)				\
raid_attr_show_internal(attr, %s, name,					\
	const char *name;						\
	code								\
	name = raid_##states##_name(rd->attr);				\
)									\
static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)


#define raid_attr_ro_internal(attr, code)				\
raid_attr_show_internal(attr, %d, rd->attr, code)			\
static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)

#define ATTR_CODE(attr)							\
	struct raid_internal *i = device_to_raid_internal(dev);		\
	if (i->f->get_##attr)						\
		i->f->get_##attr(dev->parent);

#define raid_attr_ro(attr)	raid_attr_ro_internal(attr, )
#define raid_attr_ro_fn(attr)	raid_attr_ro_internal(attr, ATTR_CODE(attr))
#define raid_attr_ro_state(attr)	raid_attr_ro_states(attr, attr, )
#define raid_attr_ro_state_fn(attr)	raid_attr_ro_states(attr, attr, ATTR_CODE(attr))


raid_attr_ro_state(level);
raid_attr_ro_fn(resync);
raid_attr_ro_state_fn(state);

static void raid_component_release(struct device *dev)
{
	struct raid_component *rc =
		container_of(dev, struct raid_component, dev);
	dev_printk(KERN_ERR, rc->dev.parent, "COMPONENT RELEASE\n");
	put_device(rc->dev.parent);
	kfree(rc);
}

int raid_component_add(struct raid_template *r,struct device *raid_dev,
		       struct device *component_dev)
{
	struct device *cdev =
		attribute_container_find_class_device(&r->raid_attrs.ac,
						      raid_dev);
	struct raid_component *rc;
	struct raid_data *rd = dev_get_drvdata(cdev);
	int err;

	rc = kzalloc(sizeof(*rc), GFP_KERNEL);
	if (!rc)
		return -ENOMEM;

	INIT_LIST_HEAD(&rc->node);
	device_initialize(&rc->dev);
	rc->dev.release = raid_component_release;
	rc->dev.parent = get_device(component_dev);
	rc->num = rd->component_count++;

	dev_set_name(&rc->dev, "component-%d", rc->num);
	list_add_tail(&rc->node, &rd->component_list);
	rc->dev.class = &raid_class.class;
	err = device_add(&rc->dev);
	if (err)
		goto err_out;

	return 0;

err_out:
	list_del(&rc->node);
	rd->component_count--;
	put_device(component_dev);
	kfree(rc);
	return err;
}
EXPORT_SYMBOL(raid_component_add);

struct raid_template *
raid_class_attach(struct raid_function_template *ft)
{
	struct raid_internal *i = kzalloc(sizeof(struct raid_internal),
					  GFP_KERNEL);
	int count = 0;

	if (unlikely(!i))
		return NULL;

	i->f = ft;

	i->r.raid_attrs.ac.class = &raid_class.class;
	i->r.raid_attrs.ac.match = raid_match;
	i->r.raid_attrs.ac.attrs = &i->attrs[0];

	attribute_container_register(&i->r.raid_attrs.ac);

	i->attrs[count++] = &dev_attr_level;
	i->attrs[count++] = &dev_attr_resync;
	i->attrs[count++] = &dev_attr_state;

	i->attrs[count] = NULL;
	BUG_ON(count > RAID_NUM_ATTRS);

	return &i->r;
}
EXPORT_SYMBOL(raid_class_attach);

void
raid_class_release(struct raid_template *r)
{
	struct raid_internal *i = to_raid_internal(r);

	BUG_ON(attribute_container_unregister(&i->r.raid_attrs.ac));

	kfree(i);
}
EXPORT_SYMBOL(raid_class_release);

static __init int raid_init(void)
{
	return transport_class_register(&raid_class);
}

static __exit void raid_exit(void)
{
	transport_class_unregister(&raid_class);
}

MODULE_AUTHOR("James Bottomley");
MODULE_DESCRIPTION("RAID device class");
MODULE_LICENSE("GPL");

module_init(raid_init);
module_exit(raid_exit);
Commit	Line	Data
61a7afa2	1	/*
b1081ea6 JB	2	* raid_class.c - implementation of a simple raid visualisation class
	3	*
	4	* Copyright (c) 2005 - James Bottomley <James.Bottomley@steeleye.com>
	5	*
	6	* This file is licensed under GPLv2
	7	*
	8	* This class is designed to allow raid attributes to be visualised and
	9	* manipulated in a form independent of the underlying raid. Ultimately this
	10	* should work for both hardware and software raids.
61a7afa2 JB	11	*/
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/list.h>
8c65b4a6 TS	15	#include <linux/slab.h>
8c65b4a6 TS	16	#include <linux/string.h>
61a7afa2 JB	17	#include <linux/raid_class.h>
	18	#include <scsi/scsi_device.h>
	19	#include <scsi/scsi_host.h>
	20
	21	#define RAID_NUM_ATTRS 3
	22
	23	struct raid_internal {
	24	struct raid_template r;
	25	struct raid_function_template *f;
	26	/* The actual attributes */
ee959b00	27	struct device_attribute private_attrs[RAID_NUM_ATTRS];
61a7afa2 JB	28	/* The array of null terminated pointers to attributes
61a7afa2 JB	29	* needed by scsi_sysfs.c */
ee959b00	30	struct device_attribute *attrs[RAID_NUM_ATTRS + 1];
61a7afa2 JB	31	};
	32
	33	struct raid_component {
	34	struct list_head node;
ee959b00	35	struct device dev;
61a7afa2 JB	36	int num;
	37	};
	38
	39	#define to_raid_internal(tmpl) container_of(tmpl, struct raid_internal, r)
	40
	41	#define tc_to_raid_internal(tcont) ({ \
	42	struct raid_template *r = \
	43	container_of(tcont, struct raid_template, raid_attrs); \
	44	to_raid_internal(r); \
	45	})
	46
	47	#define ac_to_raid_internal(acont) ({ \
	48	struct transport_container *tc = \
	49	container_of(acont, struct transport_container, ac); \
	50	tc_to_raid_internal(tc); \
	51	})
	52
ee959b00	53	#define device_to_raid_internal(dev) ({ \
61a7afa2	54	struct attribute_container *ac = \
ee959b00	55	attribute_container_classdev_to_container(dev); \
61a7afa2 JB	56	ac_to_raid_internal(ac); \
	57	})
	58
	59
	60	static int raid_match(struct attribute_container cont, struct device dev)
	61	{
	62	/* We have to look for every subsystem that could house
	63	* emulated RAID devices, so start with SCSI */
	64	struct raid_internal *i = ac_to_raid_internal(cont);
	65
	66	if (scsi_is_sdev_device(dev)) {
	67	struct scsi_device *sdev = to_scsi_device(dev);
	68
	69	if (i->f->cookie != sdev->host->hostt)
	70	return 0;
	71
	72	return i->f->is_raid(dev);
	73	}
	74	/* FIXME: look at other subsystems too */
	75	return 0;
	76	}
	77
	78	static int raid_setup(struct transport_container tc, struct device dev,
ee959b00	79	struct device *cdev)
61a7afa2 JB	80	{
	81	struct raid_data *rd;
	82
ee959b00	83	BUG_ON(dev_get_drvdata(cdev));
61a7afa2	84
b1081ea6	85	rd = kzalloc(sizeof(*rd), GFP_KERNEL);
61a7afa2 JB	86	if (!rd)
	87	return -ENOMEM;
	88
61a7afa2	89	INIT_LIST_HEAD(&rd->component_list);
ee959b00	90	dev_set_drvdata(cdev, rd);
61a7afa2 JB	91
	92	return 0;
	93	}
	94
	95	static int raid_remove(struct transport_container tc, struct device dev,
ee959b00	96	struct device *cdev)
61a7afa2	97	{
ee959b00	98	struct raid_data *rd = dev_get_drvdata(cdev);
61a7afa2	99	struct raid_component rc, next;
b1081ea6	100	dev_printk(KERN_ERR, dev, "RAID REMOVE\n");
ee959b00	101	dev_set_drvdata(cdev, NULL);
61a7afa2	102	list_for_each_entry_safe(rc, next, &rd->component_list, node) {
61a7afa2	103	list_del(&rc->node);
ee959b00 TJ	104	dev_printk(KERN_ERR, rc->dev.parent, "RAID COMPONENT REMOVE\n");
ee959b00 TJ	105	device_unregister(&rc->dev);
61a7afa2	106	}
b1081ea6 JB	107	dev_printk(KERN_ERR, dev, "RAID REMOVE DONE\n");
b1081ea6 JB	108	kfree(rd);
61a7afa2 JB	109	return 0;
	110	}
	111
	112	static DECLARE_TRANSPORT_CLASS(raid_class,
	113	"raid_devices",
	114	raid_setup,
	115	raid_remove,
	116	NULL);
	117
0ad78200	118	static const struct {
61a7afa2 JB	119	enum raid_state value;
	120	char *name;
	121	} raid_states[] = {
b1081ea6 JB	122	{ RAID_STATE_UNKNOWN, "unknown" },
	123	{ RAID_STATE_ACTIVE, "active" },
	124	{ RAID_STATE_DEGRADED, "degraded" },
	125	{ RAID_STATE_RESYNCING, "resyncing" },
	126	{ RAID_STATE_OFFLINE, "offline" },
61a7afa2 JB	127	};
	128
	129	static const char *raid_state_name(enum raid_state state)
	130	{
	131	int i;
	132	char *name = NULL;
	133
6391a113	134	for (i = 0; i < ARRAY_SIZE(raid_states); i++) {
61a7afa2 JB	135	if (raid_states[i].value == state) {
	136	name = raid_states[i].name;
	137	break;
	138	}
	139	}
	140	return name;
	141	}
	142
b1081ea6 JB	143	static struct {
	144	enum raid_level value;
	145	char *name;
	146	} raid_levels[] = {
	147	{ RAID_LEVEL_UNKNOWN, "unknown" },
	148	{ RAID_LEVEL_LINEAR, "linear" },
	149	{ RAID_LEVEL_0, "raid0" },
	150	{ RAID_LEVEL_1, "raid1" },
8e32ca49	151	{ RAID_LEVEL_10, "raid10" },
b1081ea6 JB	152	{ RAID_LEVEL_3, "raid3" },
	153	{ RAID_LEVEL_4, "raid4" },
	154	{ RAID_LEVEL_5, "raid5" },
8e32ca49	155	{ RAID_LEVEL_50, "raid50" },
b1081ea6 JB	156	{ RAID_LEVEL_6, "raid6" },
	157	};
	158
	159	static const char *raid_level_name(enum raid_level level)
	160	{
	161	int i;
	162	char *name = NULL;
	163
6391a113	164	for (i = 0; i < ARRAY_SIZE(raid_levels); i++) {
b1081ea6 JB	165	if (raid_levels[i].value == level) {
	166	name = raid_levels[i].name;
	167	break;
	168	}
	169	}
	170	return name;
	171	}
61a7afa2 JB	172
61a7afa2 JB	173	#define raid_attr_show_internal(attr, fmt, var, code) \
ee959b00 TJ	174	static ssize_t raid_show_##attr(struct device *dev, \
	175	struct device_attribute *attr, \
	176	char *buf) \
61a7afa2	177	{ \
ee959b00	178	struct raid_data *rd = dev_get_drvdata(dev); \
61a7afa2 JB	179	code \
	180	return snprintf(buf, 20, #fmt "\n", var); \
	181	}
	182
	183	#define raid_attr_ro_states(attr, states, code) \
	184	raid_attr_show_internal(attr, %s, name, \
	185	const char *name; \
	186	code \
	187	name = raid_##states##_name(rd->attr); \
	188	) \
ee959b00	189	static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)
61a7afa2 JB	190
	191
	192	#define raid_attr_ro_internal(attr, code) \
	193	raid_attr_show_internal(attr, %d, rd->attr, code) \
ee959b00	194	static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)
61a7afa2 JB	195
61a7afa2 JB	196	#define ATTR_CODE(attr) \
ee959b00	197	struct raid_internal *i = device_to_raid_internal(dev); \
61a7afa2	198	if (i->f->get_##attr) \
ee959b00	199	i->f->get_##attr(dev->parent);
61a7afa2 JB	200
	201	#define raid_attr_ro(attr) raid_attr_ro_internal(attr, )
	202	#define raid_attr_ro_fn(attr) raid_attr_ro_internal(attr, ATTR_CODE(attr))
b1081ea6 JB	203	#define raid_attr_ro_state(attr) raid_attr_ro_states(attr, attr, )
	204	#define raid_attr_ro_state_fn(attr) raid_attr_ro_states(attr, attr, ATTR_CODE(attr))
	205
61a7afa2	206
b1081ea6	207	raid_attr_ro_state(level);
61a7afa2	208	raid_attr_ro_fn(resync);
b1081ea6 JB	209	raid_attr_ro_state_fn(state);
b1081ea6 JB	210
ee959b00	211	static void raid_component_release(struct device *dev)
b1081ea6	212	{
ee959b00 TJ	213	struct raid_component *rc =
	214	container_of(dev, struct raid_component, dev);
	215	dev_printk(KERN_ERR, rc->dev.parent, "COMPONENT RELEASE\n");
	216	put_device(rc->dev.parent);
b1081ea6 JB	217	kfree(rc);
b1081ea6 JB	218	}
61a7afa2	219
ed542bed JG	220	int raid_component_add(struct raid_template r,struct device raid_dev,
ed542bed JG	221	struct device *component_dev)
61a7afa2	222	{
ee959b00	223	struct device *cdev =
61a7afa2 JB	224	attribute_container_find_class_device(&r->raid_attrs.ac,
	225	raid_dev);
	226	struct raid_component *rc;
ee959b00	227	struct raid_data *rd = dev_get_drvdata(cdev);
ed542bed	228	int err;
61a7afa2	229
b1081ea6	230	rc = kzalloc(sizeof(*rc), GFP_KERNEL);
61a7afa2	231	if (!rc)
ed542bed	232	return -ENOMEM;
61a7afa2 JB	233
61a7afa2 JB	234	INIT_LIST_HEAD(&rc->node);
ee959b00 TJ	235	device_initialize(&rc->dev);
	236	rc->dev.release = raid_component_release;
	237	rc->dev.parent = get_device(component_dev);
61a7afa2 JB	238	rc->num = rd->component_count++;
61a7afa2 JB	239
71610f55	240	dev_set_name(&rc->dev, "component-%d", rc->num);
61a7afa2	241	list_add_tail(&rc->node, &rd->component_list);
ee959b00 TJ	242	rc->dev.class = &raid_class.class;
ee959b00 TJ	243	err = device_add(&rc->dev);
ed542bed JG	244	if (err)
	245	goto err_out;
	246
	247	return 0;
	248
	249	err_out:
	250	list_del(&rc->node);
	251	rd->component_count--;
	252	put_device(component_dev);
	253	kfree(rc);
	254	return err;
61a7afa2 JB	255	}
	256	EXPORT_SYMBOL(raid_component_add);
	257
	258	struct raid_template *
	259	raid_class_attach(struct raid_function_template *ft)
	260	{
b1081ea6	261	struct raid_internal *i = kzalloc(sizeof(struct raid_internal),
61a7afa2 JB	262	GFP_KERNEL);
	263	int count = 0;
	264
	265	if (unlikely(!i))
	266	return NULL;
	267
61a7afa2 JB	268	i->f = ft;
	269
	270	i->r.raid_attrs.ac.class = &raid_class.class;
	271	i->r.raid_attrs.ac.match = raid_match;
	272	i->r.raid_attrs.ac.attrs = &i->attrs[0];
	273
	274	attribute_container_register(&i->r.raid_attrs.ac);
	275
ee959b00 TJ	276	i->attrs[count++] = &dev_attr_level;
	277	i->attrs[count++] = &dev_attr_resync;
	278	i->attrs[count++] = &dev_attr_state;
61a7afa2 JB	279
	280	i->attrs[count] = NULL;
	281	BUG_ON(count > RAID_NUM_ATTRS);
	282
	283	return &i->r;
	284	}
	285	EXPORT_SYMBOL(raid_class_attach);
	286
	287	void
	288	raid_class_release(struct raid_template *r)
	289	{
	290	struct raid_internal *i = to_raid_internal(r);
	291
2f3edc69	292	BUG_ON(attribute_container_unregister(&i->r.raid_attrs.ac));
61a7afa2 JB	293
	294	kfree(i);
	295	}
	296	EXPORT_SYMBOL(raid_class_release);
	297
	298	static __init int raid_init(void)
	299	{
	300	return transport_class_register(&raid_class);
	301	}
	302
	303	static __exit void raid_exit(void)
	304	{
	305	transport_class_unregister(&raid_class);
	306	}
	307
	308	MODULE_AUTHOR("James Bottomley");
	309	MODULE_DESCRIPTION("RAID device class");
	310	MODULE_LICENSE("GPL");
	311
	312	module_init(raid_init);
	313	module_exit(raid_exit);
	314