1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * This file is part of UBIFS.
4 *
5 * Copyright (C) 2021 Cisco Systems
6 *
7 * Author: Stefan Schaeckeler
8 */
9
10
11 #include <linux/fs.h>
12 #include "ubifs.h"
13
14 enum attr_id_t {
15 attr_errors_magic,
16 attr_errors_node,
17 attr_errors_crc,
18 };
19
20 struct ubifs_attr {
21 struct attribute attr;
22 enum attr_id_t attr_id;
23 };
24
25 #define UBIFS_ATTR(_name, _mode, _id) \
26 static struct ubifs_attr ubifs_attr_##_name = { \
27 .attr = {.name = __stringify(_name), .mode = _mode }, \
28 .attr_id = attr_##_id, \
29 }
30
31 #define UBIFS_ATTR_FUNC(_name, _mode) UBIFS_ATTR(_name, _mode, _name)
32
33 UBIFS_ATTR_FUNC(errors_magic, 0444);
34 UBIFS_ATTR_FUNC(errors_crc, 0444);
35 UBIFS_ATTR_FUNC(errors_node, 0444);
36
37 #define ATTR_LIST(name) (&ubifs_attr_##name.attr)
38
39 static struct attribute *ubifs_attrs[] = {
40 ATTR_LIST(errors_magic),
41 ATTR_LIST(errors_node),
42 ATTR_LIST(errors_crc),
43 NULL,
44 };
45 ATTRIBUTE_GROUPS(ubifs);
46
ubifs_attr_show(struct kobject * kobj,struct attribute * attr,char * buf)47 static ssize_t ubifs_attr_show(struct kobject *kobj,
48 struct attribute *attr, char *buf)
49 {
50 struct ubifs_info *sbi = container_of(kobj, struct ubifs_info,
51 kobj);
52
53 struct ubifs_attr *a = container_of(attr, struct ubifs_attr, attr);
54
55 switch (a->attr_id) {
56 case attr_errors_magic:
57 return sysfs_emit(buf, "%u\n", sbi->stats->magic_errors);
58 case attr_errors_node:
59 return sysfs_emit(buf, "%u\n", sbi->stats->node_errors);
60 case attr_errors_crc:
61 return sysfs_emit(buf, "%u\n", sbi->stats->crc_errors);
62 }
63 return 0;
64 };
65
ubifs_sb_release(struct kobject * kobj)66 static void ubifs_sb_release(struct kobject *kobj)
67 {
68 struct ubifs_info *c = container_of(kobj, struct ubifs_info, kobj);
69
70 complete(&c->kobj_unregister);
71 }
72
73 static const struct sysfs_ops ubifs_attr_ops = {
74 .show = ubifs_attr_show,
75 };
76
77 static struct kobj_type ubifs_sb_ktype = {
78 .default_groups = ubifs_groups,
79 .sysfs_ops = &ubifs_attr_ops,
80 .release = ubifs_sb_release,
81 };
82
83 static struct kobj_type ubifs_ktype = {
84 .sysfs_ops = &ubifs_attr_ops,
85 };
86
87 static struct kset ubifs_kset = {
88 .kobj = {.ktype = &ubifs_ktype},
89 };
90
ubifs_sysfs_register(struct ubifs_info * c)91 int ubifs_sysfs_register(struct ubifs_info *c)
92 {
93 int ret, n;
94 char dfs_dir_name[UBIFS_DFS_DIR_LEN+1];
95
96 c->stats = kzalloc(sizeof(struct ubifs_stats_info), GFP_KERNEL);
97 if (!c->stats) {
98 ret = -ENOMEM;
99 goto out_last;
100 }
101 n = snprintf(dfs_dir_name, UBIFS_DFS_DIR_LEN + 1, UBIFS_DFS_DIR_NAME,
102 c->vi.ubi_num, c->vi.vol_id);
103
104 if (n > UBIFS_DFS_DIR_LEN) {
105 /* The array size is too small */
106 ret = -EINVAL;
107 goto out_free;
108 }
109
110 c->kobj.kset = &ubifs_kset;
111 init_completion(&c->kobj_unregister);
112
113 ret = kobject_init_and_add(&c->kobj, &ubifs_sb_ktype, NULL,
114 "%s", dfs_dir_name);
115 if (ret)
116 goto out_put;
117
118 return 0;
119
120 out_put:
121 kobject_put(&c->kobj);
122 wait_for_completion(&c->kobj_unregister);
123 out_free:
124 kfree(c->stats);
125 out_last:
126 ubifs_err(c, "cannot create sysfs entry for ubifs%d_%d, error %d\n",
127 c->vi.ubi_num, c->vi.vol_id, ret);
128 return ret;
129 }
130
ubifs_sysfs_unregister(struct ubifs_info * c)131 void ubifs_sysfs_unregister(struct ubifs_info *c)
132 {
133 kobject_del(&c->kobj);
134 kobject_put(&c->kobj);
135 wait_for_completion(&c->kobj_unregister);
136
137 kfree(c->stats);
138 }
139
ubifs_sysfs_init(void)140 int __init ubifs_sysfs_init(void)
141 {
142 int ret;
143
144 kobject_set_name(&ubifs_kset.kobj, "ubifs");
145 ubifs_kset.kobj.parent = fs_kobj;
146 ret = kset_register(&ubifs_kset);
147
148 return ret;
149 }
150
ubifs_sysfs_exit(void)151 void ubifs_sysfs_exit(void)
152 {
153 kset_unregister(&ubifs_kset);
154 }
155