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_mount_opts); 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 69 static struct attribute *erofs_sb_attrs[] = { 70 #ifdef CONFIG_EROFS_FS_ZIP 71 ATTR_LIST(sync_decompress), 72 ATTR_LIST(drop_caches), 73 #endif 74 NULL, 75 }; 76 ATTRIBUTE_GROUPS(erofs_sb); 77 78 static struct attribute *erofs_attrs[] = { 79 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL 80 ATTR_LIST(accel), 81 #endif 82 NULL, 83 }; 84 ATTRIBUTE_GROUPS(erofs); 85 86 /* Features this copy of erofs supports */ 87 EROFS_ATTR_FEATURE(zero_padding); 88 EROFS_ATTR_FEATURE(compr_cfgs); 89 EROFS_ATTR_FEATURE(big_pcluster); 90 EROFS_ATTR_FEATURE(chunked_file); 91 EROFS_ATTR_FEATURE(device_table); 92 EROFS_ATTR_FEATURE(compr_head2); 93 EROFS_ATTR_FEATURE(sb_chksum); 94 EROFS_ATTR_FEATURE(ztailpacking); 95 EROFS_ATTR_FEATURE(fragments); 96 EROFS_ATTR_FEATURE(dedupe); 97 EROFS_ATTR_FEATURE(48bit); 98 99 static struct attribute *erofs_feat_attrs[] = { 100 ATTR_LIST(zero_padding), 101 ATTR_LIST(compr_cfgs), 102 ATTR_LIST(big_pcluster), 103 ATTR_LIST(chunked_file), 104 ATTR_LIST(device_table), 105 ATTR_LIST(compr_head2), 106 ATTR_LIST(sb_chksum), 107 ATTR_LIST(ztailpacking), 108 ATTR_LIST(fragments), 109 ATTR_LIST(dedupe), 110 ATTR_LIST(48bit), 111 NULL, 112 }; 113 ATTRIBUTE_GROUPS(erofs_feat); 114 115 static unsigned char *__struct_ptr(struct erofs_sb_info *sbi, 116 int struct_type, int offset) 117 { 118 if (struct_type == struct_erofs_sb_info) 119 return (unsigned char *)sbi + offset; 120 if (struct_type == struct_erofs_mount_opts) 121 return (unsigned char *)&sbi->opt + offset; 122 return NULL; 123 } 124 125 static ssize_t erofs_attr_show(struct kobject *kobj, 126 struct attribute *attr, char *buf) 127 { 128 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, 129 s_kobj); 130 struct erofs_attr *a = container_of(attr, struct erofs_attr, attr); 131 unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset); 132 133 switch (a->attr_id) { 134 case attr_feature: 135 return sysfs_emit(buf, "supported\n"); 136 case attr_pointer_ui: 137 if (!ptr) 138 return 0; 139 return sysfs_emit(buf, "%u\n", *(unsigned int *)ptr); 140 case attr_pointer_bool: 141 if (!ptr) 142 return 0; 143 return sysfs_emit(buf, "%d\n", *(bool *)ptr); 144 case attr_accel: 145 return z_erofs_crypto_show_engines(buf, PAGE_SIZE, '\n'); 146 } 147 return 0; 148 } 149 150 static ssize_t erofs_attr_store(struct kobject *kobj, struct attribute *attr, 151 const char *buf, size_t len) 152 { 153 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, 154 s_kobj); 155 struct erofs_attr *a = container_of(attr, struct erofs_attr, attr); 156 unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset); 157 unsigned long t; 158 int ret; 159 160 switch (a->attr_id) { 161 case attr_pointer_ui: 162 if (!ptr) 163 return 0; 164 ret = kstrtoul(skip_spaces(buf), 0, &t); 165 if (ret) 166 return ret; 167 if (t != (unsigned int)t) 168 return -ERANGE; 169 #ifdef CONFIG_EROFS_FS_ZIP 170 if (!strcmp(a->attr.name, "sync_decompress") && 171 (t > EROFS_SYNC_DECOMPRESS_FORCE_OFF)) 172 return -EINVAL; 173 #endif 174 *(unsigned int *)ptr = t; 175 return len; 176 case attr_pointer_bool: 177 if (!ptr) 178 return 0; 179 ret = kstrtoul(skip_spaces(buf), 0, &t); 180 if (ret) 181 return ret; 182 if (t != 0 && t != 1) 183 return -EINVAL; 184 *(bool *)ptr = !!t; 185 return len; 186 #ifdef CONFIG_EROFS_FS_ZIP 187 case attr_drop_caches: 188 ret = kstrtoul(skip_spaces(buf), 0, &t); 189 if (ret) 190 return ret; 191 if (t < 1 || t > 3) 192 return -EINVAL; 193 194 if (t & 2) 195 z_erofs_shrink_scan(sbi, ~0UL); 196 if (t & 1) 197 invalidate_mapping_pages(MNGD_MAPPING(sbi), 0, -1); 198 return len; 199 #endif 200 #ifdef CONFIG_EROFS_FS_ZIP_ACCEL 201 case attr_accel: 202 buf = skip_spaces(buf); 203 z_erofs_crypto_disable_all_engines(); 204 while (*buf) { 205 t = strcspn(buf, "\n"); 206 ret = z_erofs_crypto_enable_engine(buf, t); 207 if (ret < 0) 208 return ret; 209 buf += buf[t] != '\0' ? t + 1 : t; 210 } 211 return len; 212 #endif 213 } 214 return 0; 215 } 216 217 static void erofs_sb_release(struct kobject *kobj) 218 { 219 struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, 220 s_kobj); 221 complete(&sbi->s_kobj_unregister); 222 } 223 224 static const struct sysfs_ops erofs_attr_ops = { 225 .show = erofs_attr_show, 226 .store = erofs_attr_store, 227 }; 228 229 static const struct kobj_type erofs_sb_ktype = { 230 .default_groups = erofs_sb_groups, 231 .sysfs_ops = &erofs_attr_ops, 232 .release = erofs_sb_release, 233 }; 234 235 static const struct kobj_type erofs_ktype = { 236 .default_groups = erofs_groups, 237 .sysfs_ops = &erofs_attr_ops, 238 }; 239 240 static struct kset erofs_root = { 241 .kobj = {.ktype = &erofs_ktype}, 242 }; 243 244 static const struct kobj_type erofs_feat_ktype = { 245 .default_groups = erofs_feat_groups, 246 .sysfs_ops = &erofs_attr_ops, 247 }; 248 249 static struct kobject erofs_feat = { 250 .kset = &erofs_root, 251 }; 252 253 int erofs_register_sysfs(struct super_block *sb) 254 { 255 struct erofs_sb_info *sbi = EROFS_SB(sb); 256 int err; 257 258 sbi->s_kobj.kset = &erofs_root; 259 init_completion(&sbi->s_kobj_unregister); 260 err = kobject_init_and_add(&sbi->s_kobj, &erofs_sb_ktype, NULL, "%s", 261 sb->s_sysfs_name); 262 if (err) { 263 kobject_put(&sbi->s_kobj); 264 wait_for_completion(&sbi->s_kobj_unregister); 265 } 266 return err; 267 } 268 269 void erofs_unregister_sysfs(struct super_block *sb) 270 { 271 struct erofs_sb_info *sbi = EROFS_SB(sb); 272 273 if (sbi->s_kobj.state_in_sysfs) { 274 kobject_del(&sbi->s_kobj); 275 kobject_put(&sbi->s_kobj); 276 wait_for_completion(&sbi->s_kobj_unregister); 277 } 278 } 279 280 void erofs_exit_sysfs(void) 281 { 282 kobject_put(&erofs_feat); 283 kset_unregister(&erofs_root); 284 } 285 286 int __init erofs_init_sysfs(void) 287 { 288 int ret; 289 290 kobject_set_name(&erofs_root.kobj, "erofs"); 291 erofs_root.kobj.parent = fs_kobj; 292 ret = kset_register(&erofs_root); 293 if (!ret) { 294 ret = kobject_init_and_add(&erofs_feat, &erofs_feat_ktype, 295 NULL, "features"); 296 if (!ret) 297 return 0; 298 erofs_exit_sysfs(); 299 } 300 return ret; 301 } 302