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