// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C), 2008-2021, OPPO Mobile Comm Corp., Ltd. * https://www.oppo.com/ */ #include #include #include "internal.h" enum { attr_feature, attr_pointer_ui, attr_pointer_bool, }; enum { struct_erofs_sb_info, struct_erofs_mount_opts, }; struct erofs_attr { struct attribute attr; short attr_id; int struct_type, offset; }; #define EROFS_ATTR(_name, _mode, _id) \ static struct erofs_attr erofs_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ .attr_id = attr_##_id, \ } #define EROFS_ATTR_FUNC(_name, _mode) EROFS_ATTR(_name, _mode, _name) #define EROFS_ATTR_FEATURE(_name) EROFS_ATTR(_name, 0444, feature) #define EROFS_ATTR_OFFSET(_name, _mode, _id, _struct) \ static struct erofs_attr erofs_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ .attr_id = attr_##_id, \ .struct_type = struct_##_struct, \ .offset = offsetof(struct _struct, _name),\ } #define EROFS_ATTR_RW(_name, _id, _struct) \ EROFS_ATTR_OFFSET(_name, 0644, _id, _struct) #define EROFS_RO_ATTR(_name, _id, _struct) \ EROFS_ATTR_OFFSET(_name, 0444, _id, _struct) #define EROFS_ATTR_RW_UI(_name, _struct) \ EROFS_ATTR_RW(_name, pointer_ui, _struct) #define EROFS_ATTR_RW_BOOL(_name, _struct) \ EROFS_ATTR_RW(_name, pointer_bool, _struct) #define ATTR_LIST(name) (&erofs_attr_##name.attr) #ifdef CONFIG_EROFS_FS_ZIP EROFS_ATTR_RW_UI(sync_decompress, erofs_mount_opts); #endif static struct attribute *erofs_attrs[] = { #ifdef CONFIG_EROFS_FS_ZIP ATTR_LIST(sync_decompress), #endif NULL, }; ATTRIBUTE_GROUPS(erofs); /* Features this copy of erofs supports */ EROFS_ATTR_FEATURE(zero_padding); EROFS_ATTR_FEATURE(compr_cfgs); EROFS_ATTR_FEATURE(big_pcluster); EROFS_ATTR_FEATURE(chunked_file); EROFS_ATTR_FEATURE(device_table); EROFS_ATTR_FEATURE(compr_head2); EROFS_ATTR_FEATURE(sb_chksum); EROFS_ATTR_FEATURE(ztailpacking); EROFS_ATTR_FEATURE(fragments); EROFS_ATTR_FEATURE(dedupe); static struct attribute *erofs_feat_attrs[] = { ATTR_LIST(zero_padding), ATTR_LIST(compr_cfgs), ATTR_LIST(big_pcluster), ATTR_LIST(chunked_file), ATTR_LIST(device_table), ATTR_LIST(compr_head2), ATTR_LIST(sb_chksum), ATTR_LIST(ztailpacking), ATTR_LIST(fragments), ATTR_LIST(dedupe), NULL, }; ATTRIBUTE_GROUPS(erofs_feat); static unsigned char *__struct_ptr(struct erofs_sb_info *sbi, int struct_type, int offset) { if (struct_type == struct_erofs_sb_info) return (unsigned char *)sbi + offset; if (struct_type == struct_erofs_mount_opts) return (unsigned char *)&sbi->opt + offset; return NULL; } static ssize_t erofs_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, s_kobj); struct erofs_attr *a = container_of(attr, struct erofs_attr, attr); unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset); switch (a->attr_id) { case attr_feature: return sysfs_emit(buf, "supported\n"); case attr_pointer_ui: if (!ptr) return 0; return sysfs_emit(buf, "%u\n", *(unsigned int *)ptr); case attr_pointer_bool: if (!ptr) return 0; return sysfs_emit(buf, "%d\n", *(bool *)ptr); } return 0; } static ssize_t erofs_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t len) { struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, s_kobj); struct erofs_attr *a = container_of(attr, struct erofs_attr, attr); unsigned char *ptr = __struct_ptr(sbi, a->struct_type, a->offset); unsigned long t; int ret; switch (a->attr_id) { case attr_pointer_ui: if (!ptr) return 0; ret = kstrtoul(skip_spaces(buf), 0, &t); if (ret) return ret; if (t != (unsigned int)t) return -ERANGE; #ifdef CONFIG_EROFS_FS_ZIP if (!strcmp(a->attr.name, "sync_decompress") && (t > EROFS_SYNC_DECOMPRESS_FORCE_OFF)) return -EINVAL; #endif *(unsigned int *)ptr = t; return len; case attr_pointer_bool: if (!ptr) return 0; ret = kstrtoul(skip_spaces(buf), 0, &t); if (ret) return ret; if (t != 0 && t != 1) return -EINVAL; *(bool *)ptr = !!t; return len; } return 0; } static void erofs_sb_release(struct kobject *kobj) { struct erofs_sb_info *sbi = container_of(kobj, struct erofs_sb_info, s_kobj); complete(&sbi->s_kobj_unregister); } static const struct sysfs_ops erofs_attr_ops = { .show = erofs_attr_show, .store = erofs_attr_store, }; static const struct kobj_type erofs_sb_ktype = { .default_groups = erofs_groups, .sysfs_ops = &erofs_attr_ops, .release = erofs_sb_release, }; static const struct kobj_type erofs_ktype = { .sysfs_ops = &erofs_attr_ops, }; static struct kset erofs_root = { .kobj = {.ktype = &erofs_ktype}, }; static const struct kobj_type erofs_feat_ktype = { .default_groups = erofs_feat_groups, .sysfs_ops = &erofs_attr_ops, }; static struct kobject erofs_feat = { .kset = &erofs_root, }; int erofs_register_sysfs(struct super_block *sb) { struct erofs_sb_info *sbi = EROFS_SB(sb); int err; sbi->s_kobj.kset = &erofs_root; init_completion(&sbi->s_kobj_unregister); err = kobject_init_and_add(&sbi->s_kobj, &erofs_sb_ktype, NULL, "%s", sb->s_sysfs_name); if (err) { kobject_put(&sbi->s_kobj); wait_for_completion(&sbi->s_kobj_unregister); } return err; } void erofs_unregister_sysfs(struct super_block *sb) { struct erofs_sb_info *sbi = EROFS_SB(sb); if (sbi->s_kobj.state_in_sysfs) { kobject_del(&sbi->s_kobj); kobject_put(&sbi->s_kobj); wait_for_completion(&sbi->s_kobj_unregister); } } int __init erofs_init_sysfs(void) { int ret; kobject_set_name(&erofs_root.kobj, "erofs"); erofs_root.kobj.parent = fs_kobj; ret = kset_register(&erofs_root); if (ret) goto root_err; ret = kobject_init_and_add(&erofs_feat, &erofs_feat_ktype, NULL, "features"); if (ret) goto feat_err; return ret; feat_err: kobject_put(&erofs_feat); kset_unregister(&erofs_root); root_err: return ret; } void erofs_exit_sysfs(void) { kobject_put(&erofs_feat); kset_unregister(&erofs_root); }