1 // SPDX-License-Identifier: GPL-2.0 1
2 /*
3 * Copyright 2021 Google LLC
4 *
5 * sysfs support for blk-crypto. This file co
6 * crypto capabilities of devices via /sys/blo
7 */
8
9 #include <linux/blk-crypto-profile.h>
10
11 #include "blk-crypto-internal.h"
12
13 struct blk_crypto_kobj {
14 struct kobject kobj;
15 struct blk_crypto_profile *profile;
16 };
17
18 struct blk_crypto_attr {
19 struct attribute attr;
20 ssize_t (*show)(struct blk_crypto_prof
21 struct blk_crypto_attr
22 };
23
24 static struct blk_crypto_profile *kobj_to_cryp
25 {
26 return container_of(kobj, struct blk_c
27 }
28
29 static struct blk_crypto_attr *attr_to_crypto_
30 {
31 return container_of(attr, struct blk_c
32 }
33
34 static ssize_t max_dun_bits_show(struct blk_cr
35 struct blk_cr
36 {
37 return sysfs_emit(page, "%u\n", 8 * pr
38 }
39
40 static ssize_t num_keyslots_show(struct blk_cr
41 struct blk_cr
42 {
43 return sysfs_emit(page, "%u\n", profil
44 }
45
46 #define BLK_CRYPTO_RO_ATTR(_name) \
47 static struct blk_crypto_attr _name##_
48
49 BLK_CRYPTO_RO_ATTR(max_dun_bits);
50 BLK_CRYPTO_RO_ATTR(num_keyslots);
51
52 static struct attribute *blk_crypto_attrs[] =
53 &max_dun_bits_attr.attr,
54 &num_keyslots_attr.attr,
55 NULL,
56 };
57
58 static const struct attribute_group blk_crypto
59 .attrs = blk_crypto_attrs,
60 };
61
62 /*
63 * The encryption mode attributes. To avoid h
64 * modes, these are initialized at boot time b
65 */
66 static struct blk_crypto_attr __blk_crypto_mod
67 static struct attribute *blk_crypto_mode_attrs
68
69 static umode_t blk_crypto_mode_is_visible(stru
70 stru
71 {
72 struct blk_crypto_profile *profile = k
73 struct blk_crypto_attr *a = attr_to_cr
74 int mode_num = a - __blk_crypto_mode_a
75
76 if (profile->modes_supported[mode_num]
77 return 0444;
78 return 0;
79 }
80
81 static ssize_t blk_crypto_mode_show(struct blk
82 struct blk
83 {
84 int mode_num = attr - __blk_crypto_mod
85
86 return sysfs_emit(page, "0x%x\n", prof
87 }
88
89 static const struct attribute_group blk_crypto
90 .name = "modes",
91 .attrs = blk_crypto_mode_attrs,
92 .is_visible = blk_crypto_mode_is_visib
93 };
94
95 static const struct attribute_group *blk_crypt
96 &blk_crypto_attr_group,
97 &blk_crypto_modes_attr_group,
98 NULL,
99 };
100
101 static ssize_t blk_crypto_attr_show(struct kob
102 struct att
103 {
104 struct blk_crypto_profile *profile = k
105 struct blk_crypto_attr *a = attr_to_cr
106
107 return a->show(profile, a, page);
108 }
109
110 static const struct sysfs_ops blk_crypto_attr_
111 .show = blk_crypto_attr_show,
112 };
113
114 static void blk_crypto_release(struct kobject
115 {
116 kfree(container_of(kobj, struct blk_cr
117 }
118
119 static const struct kobj_type blk_crypto_ktype
120 .default_groups = blk_crypto_attr_grou
121 .sysfs_ops = &blk_crypto_attr_ops
122 .release = blk_crypto_release,
123 };
124
125 /*
126 * If the request_queue has a blk_crypto_profi
127 * subdirectory in sysfs (/sys/block/$disk/que
128 */
129 int blk_crypto_sysfs_register(struct gendisk *
130 {
131 struct request_queue *q = disk->queue;
132 struct blk_crypto_kobj *obj;
133 int err;
134
135 if (!q->crypto_profile)
136 return 0;
137
138 obj = kzalloc(sizeof(*obj), GFP_KERNEL
139 if (!obj)
140 return -ENOMEM;
141 obj->profile = q->crypto_profile;
142
143 err = kobject_init_and_add(&obj->kobj,
144 &disk->queu
145 if (err) {
146 kobject_put(&obj->kobj);
147 return err;
148 }
149 q->crypto_kobject = &obj->kobj;
150 return 0;
151 }
152
153 void blk_crypto_sysfs_unregister(struct gendis
154 {
155 kobject_put(disk->queue->crypto_kobjec
156 }
157
158 static int __init blk_crypto_sysfs_init(void)
159 {
160 int i;
161
162 BUILD_BUG_ON(BLK_ENCRYPTION_MODE_INVAL
163 for (i = 1; i < BLK_ENCRYPTION_MODE_MA
164 struct blk_crypto_attr *attr =
165
166 attr->attr.name = blk_crypto_m
167 attr->attr.mode = 0444;
168 attr->show = blk_crypto_mode_s
169 blk_crypto_mode_attrs[i - 1] =
170 }
171 return 0;
172 }
173 subsys_initcall(blk_crypto_sysfs_init);
174
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