1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C), 2008-2021, OPPO Mobile Comm Corp., Ltd.
4 * https://www.oppo.com/
5 */
6 #include <linux/sysfs.h>
7 #include <linux/kobject.h>
8
9 #include "internal.h"
10 #include "compress.h"
11
12 enum {
13 attr_feature,
14 attr_drop_caches,
15 attr_pointer_ui,
16 attr_pointer_bool,
17 attr_accel,
18 };
19
20 enum {
21 struct_erofs_sb_info,
22 struct_erofs_mount_opts,
23 };
24
25 struct erofs_attr {
26 struct attribute attr;
27 short attr_id;
28 int struct_type, offset;
29 };
30
31 #define EROFS_ATTR(_name, _mode, _id) \
32 static struct erofs_attr erofs_attr_##_name = { \
33 .attr = {.name = __stringify(_name), .mode = _mode }, \
34 .attr_id = attr_##_id, \
35 }
36 #define EROFS_ATTR_FUNC(_name, _mode) EROFS_ATTR(_name, _mode, _name)
37 #define EROFS_ATTR_FEATURE(_name) EROFS_ATTR(_name, 0444, feature)
38
39 #define EROFS_ATTR_OFFSET(_name, _mode, _id, _struct) \
40 static struct erofs_attr erofs_attr_##_name = { \
41 .attr = {.name = __stringify(_name), .mode = _mode }, \
42 .attr_id = attr_##_id, \
43 .struct_type = struct_##_struct, \
44 .offset = offsetof(struct _struct, _name),\
45 }
46
47 #define EROFS_ATTR_RW(_name, _id, _struct) \
48 EROFS_ATTR_OFFSET(_name, 0644, _id, _struct)
49
50 #define EROFS_RO_ATTR(_name, _id, _struct) \
51 EROFS_ATTR_OFFSET(_name, 0444, _id, _struct)
52
53 #define EROFS_ATTR_RW_UI(_name, _struct) \
54 EROFS_ATTR_RW(_name, pointer_ui, _struct)
55
56 #define EROFS_ATTR_RW_BOOL(_name, _struct) \
57 EROFS_ATTR_RW(_name, pointer_bool, _struct)
58
59 #define ATTR_LIST(name) (&erofs_attr_##name.attr)
60
61 #ifdef CONFIG_EROFS_FS_ZIP
62 EROFS_ATTR_RW_UI(sync_decompress, erofs_sb_info);
63 EROFS_ATTR_FUNC(drop_caches, 0200);
64 #endif
65 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL
66 EROFS_ATTR_FUNC(accel, 0644);
67 #endif
68 EROFS_ATTR_RW_UI(dir_ra_bytes, erofs_sb_info);
69
70 static struct attribute *erofs_sb_attrs[] = {
71 #ifdef CONFIG_EROFS_FS_ZIP
72 ATTR_LIST(sync_decompress),
73 ATTR_LIST(drop_caches),
74 #endif
75 ATTR_LIST(dir_ra_bytes),
76 NULL,
77 };
78 ATTRIBUTE_GROUPS(erofs_sb);
79
80 static struct attribute *erofs_attrs[] = {
81 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL
82 ATTR_LIST(accel),
83 #endif
84 NULL,
85 };
86 ATTRIBUTE_GROUPS(erofs);
87
88 /* Features this copy of erofs supports */
89 EROFS_ATTR_FEATURE(compr_cfgs);
90 EROFS_ATTR_FEATURE(big_pcluster);
91 EROFS_ATTR_FEATURE(chunked_file);
92 EROFS_ATTR_FEATURE(device_table);
93 EROFS_ATTR_FEATURE(compr_head2);
94 EROFS_ATTR_FEATURE(sb_chksum);
95 EROFS_ATTR_FEATURE(ztailpacking);
96 EROFS_ATTR_FEATURE(fragments);
97 EROFS_ATTR_FEATURE(dedupe);
98 EROFS_ATTR_FEATURE(48bit);
99 EROFS_ATTR_FEATURE(metabox);
100
101 static struct attribute *erofs_feat_attrs[] = {
102 ATTR_LIST(compr_cfgs),
103 ATTR_LIST(big_pcluster),
104 ATTR_LIST(chunked_file),
105 ATTR_LIST(device_table),
106 ATTR_LIST(compr_head2),
107 ATTR_LIST(sb_chksum),
108 ATTR_LIST(ztailpacking),
109 ATTR_LIST(fragments),
110 ATTR_LIST(dedupe),
111 ATTR_LIST(48bit),
112 ATTR_LIST(metabox),
113 NULL,
114 };
115 ATTRIBUTE_GROUPS(erofs_feat);
116
__struct_ptr(struct erofs_sb_info * sbi,int struct_type,int offset)117 static unsigned char *__struct_ptr(struct erofs_sb_info *sbi,
118 int struct_type, int offset)
119 {
120 if (struct_type == struct_erofs_sb_info)
121 return (unsigned char *)sbi + offset;
122 if (struct_type == struct_erofs_mount_opts)
123 return (unsigned char *)&sbi->opt + offset;
124 return NULL;
125 }
126
erofs_attr_show(struct kobject * kobj,struct attribute * attr,char * buf)127 static ssize_t erofs_attr_show(struct kobject *kobj,
128 struct attribute *attr, char *buf)
129 {
130 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info,
131 s_kobj);
132 struct erofs_attr *a = container_of(attr, struct erofs_attr, attr);
133 unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset);
134
135 switch (a->attr_id) {
136 case attr_feature:
137 return sysfs_emit(buf, "supported\n");
138 case attr_pointer_ui:
139 if (!ptr)
140 return 0;
141 return sysfs_emit(buf, "%u\n", *(unsigned int *)ptr);
142 case attr_pointer_bool:
143 if (!ptr)
144 return 0;
145 return sysfs_emit(buf, "%d\n", *(bool *)ptr);
146 case attr_accel:
147 return z_erofs_crypto_show_engines(buf, PAGE_SIZE, '\n');
148 }
149 return 0;
150 }
151
erofs_attr_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t len)152 static ssize_t erofs_attr_store(struct kobject *kobj, struct attribute *attr,
153 const char *buf, size_t len)
154 {
155 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info,
156 s_kobj);
157 struct erofs_attr *a = container_of(attr, struct erofs_attr, attr);
158 unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset);
159 unsigned long t;
160 int ret;
161
162 switch (a->attr_id) {
163 case attr_pointer_ui:
164 if (!ptr)
165 return 0;
166 ret = kstrtoul(skip_spaces(buf), 0, &t);
167 if (ret)
168 return ret;
169 if (t != (unsigned int)t)
170 return -ERANGE;
171 if (IS_ENABLED(CONFIG_EROFS_FS_ZIP) &&
172 !strcmp(a->attr.name, "sync_decompress") &&
173 (t > EROFS_SYNC_DECOMPRESS_FORCE_OFF))
174 return -EINVAL;
175 *(unsigned int *)ptr = t;
176 return len;
177 case attr_pointer_bool:
178 if (!ptr)
179 return 0;
180 ret = kstrtoul(skip_spaces(buf), 0, &t);
181 if (ret)
182 return ret;
183 if (t != 0 && t != 1)
184 return -EINVAL;
185 *(bool *)ptr = !!t;
186 return len;
187 #ifdef CONFIG_EROFS_FS_ZIP
188 case attr_drop_caches:
189 ret = kstrtoul(skip_spaces(buf), 0, &t);
190 if (ret)
191 return ret;
192 if (t < 1 || t > 3)
193 return -EINVAL;
194
195 if (t & 2)
196 z_erofs_shrink_scan(sbi, ~0UL);
197 if (t & 1)
198 invalidate_mapping_pages(MNGD_MAPPING(sbi), 0, -1);
199 return len;
200 #endif
201 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL
202 case attr_accel:
203 buf = skip_spaces(buf);
204 z_erofs_crypto_disable_all_engines();
205 while (*buf) {
206 t = strcspn(buf, "\n");
207 ret = z_erofs_crypto_enable_engine(buf, t);
208 if (ret < 0)
209 return ret;
210 buf += buf[t] != '\0' ? t + 1 : t;
211 }
212 return len;
213 #endif
214 }
215 return 0;
216 }
217
erofs_sb_release(struct kobject * kobj)218 static void erofs_sb_release(struct kobject *kobj)
219 {
220 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info,
221 s_kobj);
222 complete(&sbi->s_kobj_unregister);
223 }
224
225 static const struct sysfs_ops erofs_attr_ops = {
226 .show = erofs_attr_show,
227 .store = erofs_attr_store,
228 };
229
230 static const struct kobj_type erofs_sb_ktype = {
231 .default_groups = erofs_sb_groups,
232 .sysfs_ops = &erofs_attr_ops,
233 .release = erofs_sb_release,
234 };
235
236 static const struct kobj_type erofs_ktype = {
237 .default_groups = erofs_groups,
238 .sysfs_ops = &erofs_attr_ops,
239 };
240
241 static struct kset erofs_root = {
242 .kobj = {.ktype = &erofs_ktype},
243 };
244
245 static const struct kobj_type erofs_feat_ktype = {
246 .default_groups = erofs_feat_groups,
247 .sysfs_ops = &erofs_attr_ops,
248 };
249
250 static struct kobject erofs_feat = {
251 .kset = &erofs_root,
252 };
253
erofs_register_sysfs(struct super_block * sb)254 int erofs_register_sysfs(struct super_block *sb)
255 {
256 struct erofs_sb_info *sbi = EROFS_SB(sb);
257 int err;
258
259 sbi->s_kobj.kset = &erofs_root;
260 init_completion(&sbi->s_kobj_unregister);
261 err = kobject_init_and_add(&sbi->s_kobj, &erofs_sb_ktype, NULL, "%s",
262 sb->s_sysfs_name);
263 if (err) {
264 kobject_put(&sbi->s_kobj);
265 wait_for_completion(&sbi->s_kobj_unregister);
266 }
267 return err;
268 }
269
erofs_unregister_sysfs(struct super_block * sb)270 void erofs_unregister_sysfs(struct super_block *sb)
271 {
272 struct erofs_sb_info *sbi = EROFS_SB(sb);
273
274 if (sbi->s_kobj.state_in_sysfs) {
275 kobject_del(&sbi->s_kobj);
276 kobject_put(&sbi->s_kobj);
277 wait_for_completion(&sbi->s_kobj_unregister);
278 }
279 }
280
erofs_exit_sysfs(void)281 void erofs_exit_sysfs(void)
282 {
283 kobject_put(&erofs_feat);
284 kset_unregister(&erofs_root);
285 }
286
erofs_init_sysfs(void)287 int __init erofs_init_sysfs(void)
288 {
289 int ret;
290
291 kobject_set_name(&erofs_root.kobj, "erofs");
292 erofs_root.kobj.parent = fs_kobj;
293 ret = kset_register(&erofs_root);
294 if (!ret) {
295 ret = kobject_init_and_add(&erofs_feat, &erofs_feat_ktype,
296 NULL, "features");
297 if (!ret)
298 return 0;
299 erofs_exit_sysfs();
300 }
301 return ret;
302 }
303