[linux-block.git] / drivers / md / dm-sysfs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2008 Red Hat, Inc. All rights reserved.
 *
 * This file is released under the GPL.
 */

#include <linux/sysfs.h>
#include <linux/dm-ioctl.h>
#include "dm-core.h"
#include "dm-rq.h"

struct dm_sysfs_attr {
	struct attribute attr;
	ssize_t (*show)(struct mapped_device *md, char *p);
	ssize_t (*store)(struct mapped_device *md, const char *p, size_t count);
};

#define DM_ATTR_RO(_name) \
struct dm_sysfs_attr dm_attr_##_name = \
	__ATTR(_name, 0444, dm_attr_##_name##_show, NULL)

static ssize_t dm_attr_show(struct kobject *kobj, struct attribute *attr,
			    char *page)
{
	struct dm_sysfs_attr *dm_attr;
	struct mapped_device *md;
	ssize_t ret;

	dm_attr = container_of(attr, struct dm_sysfs_attr, attr);
	if (!dm_attr->show)
		return -EIO;

	md = dm_get_from_kobject(kobj);
	if (!md)
		return -EINVAL;

	ret = dm_attr->show(md, page);
	dm_put(md);

	return ret;
}

#define DM_ATTR_RW(_name) \
struct dm_sysfs_attr dm_attr_##_name = \
	__ATTR(_name, 0644, dm_attr_##_name##_show, dm_attr_##_name##_store)

static ssize_t dm_attr_store(struct kobject *kobj, struct attribute *attr,
			     const char *page, size_t count)
{
	struct dm_sysfs_attr *dm_attr;
	struct mapped_device *md;
	ssize_t ret;

	dm_attr = container_of(attr, struct dm_sysfs_attr, attr);
	if (!dm_attr->store)
		return -EIO;

	md = dm_get_from_kobject(kobj);
	if (!md)
		return -EINVAL;

	ret = dm_attr->store(md, page, count);
	dm_put(md);

	return ret;
}

static ssize_t dm_attr_name_show(struct mapped_device *md, char *buf)
{
	if (dm_copy_name_and_uuid(md, buf, NULL))
		return -EIO;

	strcat(buf, "\n");
	return strlen(buf);
}

static ssize_t dm_attr_uuid_show(struct mapped_device *md, char *buf)
{
	if (dm_copy_name_and_uuid(md, NULL, buf))
		return -EIO;

	strcat(buf, "\n");
	return strlen(buf);
}

static ssize_t dm_attr_suspended_show(struct mapped_device *md, char *buf)
{
	sprintf(buf, "%d\n", dm_suspended_md(md));

	return strlen(buf);
}

static ssize_t dm_attr_use_blk_mq_show(struct mapped_device *md, char *buf)
{
	/* Purely for userspace compatibility */
	sprintf(buf, "%d\n", true);

	return strlen(buf);
}

static DM_ATTR_RO(name);
static DM_ATTR_RO(uuid);
static DM_ATTR_RO(suspended);
static DM_ATTR_RO(use_blk_mq);
static DM_ATTR_RW(rq_based_seq_io_merge_deadline);

static struct attribute *dm_attrs[] = {
	&dm_attr_name.attr,
	&dm_attr_uuid.attr,
	&dm_attr_suspended.attr,
	&dm_attr_use_blk_mq.attr,
	&dm_attr_rq_based_seq_io_merge_deadline.attr,
	NULL,
};
ATTRIBUTE_GROUPS(dm);

static const struct sysfs_ops dm_sysfs_ops = {
	.show	= dm_attr_show,
	.store	= dm_attr_store,
};

static const struct kobj_type dm_ktype = {
	.sysfs_ops	= &dm_sysfs_ops,
	.default_groups	= dm_groups,
	.release	= dm_kobject_release,
};

/*
 * Initialize kobj
 * because nobody using md yet, no need to call explicit dm_get/put
 */
int dm_sysfs_init(struct mapped_device *md)
{
	return kobject_init_and_add(dm_kobject(md), &dm_ktype,
				    &disk_to_dev(dm_disk(md))->kobj,
				    "%s", "dm");
}

/*
 * Remove kobj, called after all references removed
 */
void dm_sysfs_exit(struct mapped_device *md)
{
	struct kobject *kobj = dm_kobject(md);

	kobject_put(kobj);
	wait_for_completion(dm_get_completion_from_kobject(kobj));
}
Commit	Line	Data
3bd94003	1	// SPDX-License-Identifier: GPL-2.0-only
784aae73 MB	2	/*
	3	* Copyright (C) 2008 Red Hat, Inc. All rights reserved.
	4	*
	5	* This file is released under the GPL.
	6	*/
	7
	8	#include <linux/sysfs.h>
	9	#include <linux/dm-ioctl.h>
4cc96131 MS	10	#include "dm-core.h"
4cc96131 MS	11	#include "dm-rq.h"
784aae73 MB	12
	13	struct dm_sysfs_attr {
	14	struct attribute attr;
02f10ba1 HM	15	ssize_t (show)(struct mapped_device md, char *p);
02f10ba1 HM	16	ssize_t (store)(struct mapped_device md, const char *p, size_t count);
784aae73 MB	17	};
	18
	19	#define DM_ATTR_RO(_name) \
	20	struct dm_sysfs_attr dm_attr_##_name = \
6a808034	21	__ATTR(_name, 0444, dm_attr_##_name##_show, NULL)
784aae73 MB	22
	23	static ssize_t dm_attr_show(struct kobject kobj, struct attribute attr,
	24	char *page)
	25	{
	26	struct dm_sysfs_attr *dm_attr;
	27	struct mapped_device *md;
	28	ssize_t ret;
	29
	30	dm_attr = container_of(attr, struct dm_sysfs_attr, attr);
	31	if (!dm_attr->show)
	32	return -EIO;
	33
	34	md = dm_get_from_kobject(kobj);
	35	if (!md)
	36	return -EINVAL;
	37
	38	ret = dm_attr->show(md, page);
	39	dm_put(md);
	40
	41	return ret;
	42	}
	43
b898320d MS	44	#define DM_ATTR_RW(_name) \
b898320d MS	45	struct dm_sysfs_attr dm_attr_##_name = \
6a808034	46	__ATTR(_name, 0644, dm_attr_##_name##_show, dm_attr_##_name##_store)
b898320d MS	47
	48	static ssize_t dm_attr_store(struct kobject kobj, struct attribute attr,
	49	const char *page, size_t count)
	50	{
	51	struct dm_sysfs_attr *dm_attr;
	52	struct mapped_device *md;
	53	ssize_t ret;
	54
	55	dm_attr = container_of(attr, struct dm_sysfs_attr, attr);
	56	if (!dm_attr->store)
	57	return -EIO;
	58
	59	md = dm_get_from_kobject(kobj);
	60	if (!md)
	61	return -EINVAL;
	62
	63	ret = dm_attr->store(md, page, count);
	64	dm_put(md);
	65
	66	return ret;
	67	}
	68
784aae73 MB	69	static ssize_t dm_attr_name_show(struct mapped_device md, char buf)
	70	{
	71	if (dm_copy_name_and_uuid(md, buf, NULL))
	72	return -EIO;
	73
	74	strcat(buf, "\n");
	75	return strlen(buf);
	76	}
	77
	78	static ssize_t dm_attr_uuid_show(struct mapped_device md, char buf)
	79	{
	80	if (dm_copy_name_and_uuid(md, NULL, buf))
	81	return -EIO;
	82
	83	strcat(buf, "\n");
	84	return strlen(buf);
	85	}
	86
486d220f PR	87	static ssize_t dm_attr_suspended_show(struct mapped_device md, char buf)
486d220f PR	88	{
4f186f8b	89	sprintf(buf, "%d\n", dm_suspended_md(md));
486d220f PR	90
	91	return strlen(buf);
	92	}
	93
17e149b8 MS	94	static ssize_t dm_attr_use_blk_mq_show(struct mapped_device md, char buf)
17e149b8 MS	95	{
6a23e05c JA	96	/* Purely for userspace compatibility */
6a23e05c JA	97	sprintf(buf, "%d\n", true);
17e149b8 MS	98
	99	return strlen(buf);
	100	}
	101
784aae73 MB	102	static DM_ATTR_RO(name);
784aae73 MB	103	static DM_ATTR_RO(uuid);
486d220f	104	static DM_ATTR_RO(suspended);
17e149b8	105	static DM_ATTR_RO(use_blk_mq);
0ce65797	106	static DM_ATTR_RW(rq_based_seq_io_merge_deadline);
784aae73 MB	107
	108	static struct attribute *dm_attrs[] = {
	109	&dm_attr_name.attr,
	110	&dm_attr_uuid.attr,
486d220f	111	&dm_attr_suspended.attr,
17e149b8	112	&dm_attr_use_blk_mq.attr,
0ce65797	113	&dm_attr_rq_based_seq_io_merge_deadline.attr,
784aae73 MB	114	NULL,
784aae73 MB	115	};
eaac0b59	116	ATTRIBUTE_GROUPS(dm);
784aae73	117
52cf25d0	118	static const struct sysfs_ops dm_sysfs_ops = {
784aae73	119	.show = dm_attr_show,
b898320d	120	.store = dm_attr_store,
784aae73 MB	121	};
784aae73 MB	122
b0bbd86a	123	static const struct kobj_type dm_ktype = {
784aae73	124	.sysfs_ops = &dm_sysfs_ops,
eaac0b59	125	.default_groups = dm_groups,
be35f486	126	.release = dm_kobject_release,
784aae73 MB	127	};
	128
	129	/*
	130	* Initialize kobj
	131	* because nobody using md yet, no need to call explicit dm_get/put
	132	*/
	133	int dm_sysfs_init(struct mapped_device *md)
	134	{
	135	return kobject_init_and_add(dm_kobject(md), &dm_ktype,
	136	&disk_to_dev(dm_disk(md))->kobj,
	137	"%s", "dm");
	138	}
	139
	140	/*
	141	* Remove kobj, called after all references removed
	142	*/
	143	void dm_sysfs_exit(struct mapped_device *md)
	144	{
be35f486	145	struct kobject *kobj = dm_kobject(md);
0ef0b471	146
be35f486 MP	147	kobject_put(kobj);
be35f486 MP	148	wait_for_completion(dm_get_completion_from_kobject(kobj));
784aae73	149	}