--- zzzz-none-000/linux-3.10.107/fs/sysfs/group.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/fs/sysfs/group.c 2021-02-04 17:41:59.000000000 +0000 @@ -3,8 +3,10 @@ * * Copyright (c) 2003 Patrick Mochel * Copyright (c) 2003 Open Source Development Lab + * Copyright (c) 2013 Greg Kroah-Hartman + * Copyright (c) 2013 The Linux Foundation * - * This file is released undert the GPL v2. + * This file is released undert the GPL v2. * */ @@ -16,42 +18,88 @@ #include "sysfs.h" -static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, +static void remove_files(struct kernfs_node *parent, const struct attribute_group *grp) { - struct attribute *const* attr; - int i; + struct attribute *const *attr; + struct bin_attribute *const *bin_attr; - for (i = 0, attr = grp->attrs; *attr; i++, attr++) - sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); + if (grp->attrs) + for (attr = grp->attrs; *attr; attr++) + kernfs_remove_by_name(parent, (*attr)->name); + if (grp->bin_attrs) + for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) + kernfs_remove_by_name(parent, (*bin_attr)->attr.name); } -static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, +static int create_files(struct kernfs_node *parent, struct kobject *kobj, const struct attribute_group *grp, int update) { - struct attribute *const* attr; + struct attribute *const *attr; + struct bin_attribute *const *bin_attr; int error = 0, i; - for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) { - umode_t mode = 0; + if (grp->attrs) { + for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) { + umode_t mode = (*attr)->mode; + + /* + * In update mode, we're changing the permissions or + * visibility. Do this by first removing then + * re-adding (if required) the file. + */ + if (update) + kernfs_remove_by_name(parent, (*attr)->name); + if (grp->is_visible) { + mode = grp->is_visible(kobj, *attr, i); + if (!mode) + continue; + } + + WARN(mode & ~(SYSFS_PREALLOC | 0664), + "Attribute %s: Invalid permissions 0%o\n", + (*attr)->name, mode); + + mode &= SYSFS_PREALLOC | 0664; + error = sysfs_add_file_mode_ns(parent, *attr, false, + mode, NULL); + if (unlikely(error)) + break; + } + if (error) { + remove_files(parent, grp); + goto exit; + } + } - /* in update mode, we're changing the permissions or - * visibility. Do this by first removing then - * re-adding (if required) the file */ - if (update) - sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); - if (grp->is_visible) { - mode = grp->is_visible(kobj, *attr, i); - if (!mode) - continue; - } - error = sysfs_add_file_mode(dir_sd, *attr, SYSFS_KOBJ_ATTR, - (*attr)->mode | mode); - if (unlikely(error)) - break; + if (grp->bin_attrs) { + for (i = 0, bin_attr = grp->bin_attrs; *bin_attr; i++, bin_attr++) { + umode_t mode = (*bin_attr)->attr.mode; + + if (update) + kernfs_remove_by_name(parent, + (*bin_attr)->attr.name); + if (grp->is_bin_visible) { + mode = grp->is_bin_visible(kobj, *bin_attr, i); + if (!mode) + continue; + } + + WARN(mode & ~(SYSFS_PREALLOC | 0664), + "Attribute %s: Invalid permissions 0%o\n", + (*bin_attr)->attr.name, mode); + + mode &= SYSFS_PREALLOC | 0664; + error = sysfs_add_file_mode_ns(parent, + &(*bin_attr)->attr, true, + mode, NULL); + if (error) + break; + } + if (error) + remove_files(parent, grp); } - if (error) - remove_files(dir_sd, kobj, grp); +exit: return error; } @@ -59,7 +107,7 @@ static int internal_create_group(struct kobject *kobj, int update, const struct attribute_group *grp) { - struct sysfs_dirent *sd; + struct kernfs_node *kn; int error; BUG_ON(!kobj || (!update && !kobj->sd)); @@ -67,24 +115,28 @@ /* Updates may happen before the object has been instantiated */ if (unlikely(update && !kobj->sd)) return -EINVAL; - if (!grp->attrs) { - WARN(1, "sysfs: attrs not set by subsystem for group: %s/%s\n", - kobj->name, grp->name ? "" : grp->name); + if (!grp->attrs && !grp->bin_attrs) { + WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n", + kobj->name, grp->name ?: ""); return -EINVAL; } if (grp->name) { - error = sysfs_create_subdir(kobj, grp->name, &sd); - if (error) - return error; + kn = kernfs_create_dir(kobj->sd, grp->name, + S_IRWXU | S_IRUGO | S_IXUGO, kobj); + if (IS_ERR(kn)) { + if (PTR_ERR(kn) == -EEXIST) + sysfs_warn_dup(kobj->sd, grp->name); + return PTR_ERR(kn); + } } else - sd = kobj->sd; - sysfs_get(sd); - error = create_files(sd, kobj, grp, update); + kn = kobj->sd; + kernfs_get(kn); + error = create_files(kn, kobj, grp, update); if (error) { if (grp->name) - sysfs_remove_subdir(sd); + kernfs_remove(kn); } - sysfs_put(sd); + kernfs_put(kn); return error; } @@ -96,13 +148,48 @@ * This function creates a group for the first time. It will explicitly * warn and error if any of the attribute files being created already exist. * - * Returns 0 on success or error. + * Returns 0 on success or error code on failure. */ int sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp) { return internal_create_group(kobj, 0, grp); } +EXPORT_SYMBOL_GPL(sysfs_create_group); + +/** + * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups + * @kobj: The kobject to create the group on + * @groups: The attribute groups to create, NULL terminated + * + * This function creates a bunch of attribute groups. If an error occurs when + * creating a group, all previously created groups will be removed, unwinding + * everything back to the original state when this function was called. + * It will explicitly warn and error if any of the attribute files being + * created already exist. + * + * Returns 0 on success or error code from sysfs_create_group on failure. + */ +int sysfs_create_groups(struct kobject *kobj, + const struct attribute_group **groups) +{ + int error = 0; + int i; + + if (!groups) + return 0; + + for (i = 0; groups[i]; i++) { + error = sysfs_create_group(kobj, groups[i]); + if (error) { + while (--i >= 0) + sysfs_remove_group(kobj, groups[i]); + break; + } + } + return error; +} +EXPORT_SYMBOL_GPL(sysfs_create_groups); /** * sysfs_update_group - given a directory kobject, update an attribute group @@ -119,38 +206,69 @@ * The primary use for this function is to call it after making a change * that affects group visibility. * - * Returns 0 on success or error. + * Returns 0 on success or error code on failure. */ int sysfs_update_group(struct kobject *kobj, const struct attribute_group *grp) { return internal_create_group(kobj, 1, grp); } +EXPORT_SYMBOL_GPL(sysfs_update_group); - - -void sysfs_remove_group(struct kobject * kobj, - const struct attribute_group * grp) +/** + * sysfs_remove_group: remove a group from a kobject + * @kobj: kobject to remove the group from + * @grp: group to remove + * + * This function removes a group of attributes from a kobject. The attributes + * previously have to have been created for this group, otherwise it will fail. + */ +void sysfs_remove_group(struct kobject *kobj, + const struct attribute_group *grp) { - struct sysfs_dirent *dir_sd = kobj->sd; - struct sysfs_dirent *sd; + struct kernfs_node *parent = kobj->sd; + struct kernfs_node *kn; if (grp->name) { - sd = sysfs_get_dirent(dir_sd, NULL, grp->name); - if (!sd) { - WARN(!sd, KERN_WARNING "sysfs group %p not found for " - "kobject '%s'\n", grp, kobject_name(kobj)); + kn = kernfs_find_and_get(parent, grp->name); + if (!kn) { + WARN(!kn, KERN_WARNING + "sysfs group %p not found for kobject '%s'\n", + grp, kobject_name(kobj)); return; } - } else - sd = sysfs_get(dir_sd); + } else { + kn = parent; + kernfs_get(kn); + } - remove_files(sd, kobj, grp); + remove_files(kn, grp); if (grp->name) - sysfs_remove_subdir(sd); + kernfs_remove(kn); - sysfs_put(sd); + kernfs_put(kn); } +EXPORT_SYMBOL_GPL(sysfs_remove_group); + +/** + * sysfs_remove_groups - remove a list of groups + * + * @kobj: The kobject for the groups to be removed from + * @groups: NULL terminated list of groups to be removed + * + * If groups is not NULL, remove the specified groups from the kobject. + */ +void sysfs_remove_groups(struct kobject *kobj, + const struct attribute_group **groups) +{ + int i; + + if (!groups) + return; + for (i = 0; groups[i]; i++) + sysfs_remove_group(kobj, groups[i]); +} +EXPORT_SYMBOL_GPL(sysfs_remove_groups); /** * sysfs_merge_group - merge files into a pre-existing attribute group. @@ -164,22 +282,22 @@ int sysfs_merge_group(struct kobject *kobj, const struct attribute_group *grp) { - struct sysfs_dirent *dir_sd; + struct kernfs_node *parent; int error = 0; struct attribute *const *attr; int i; - dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name); - if (!dir_sd) + parent = kernfs_find_and_get(kobj->sd, grp->name); + if (!parent) return -ENOENT; for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr)) - error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR); + error = sysfs_add_file(parent, *attr, false); if (error) { while (--i >= 0) - sysfs_hash_and_remove(dir_sd, NULL, (*--attr)->name); + kernfs_remove_by_name(parent, (*--attr)->name); } - sysfs_put(dir_sd); + kernfs_put(parent); return error; } @@ -193,14 +311,14 @@ void sysfs_unmerge_group(struct kobject *kobj, const struct attribute_group *grp) { - struct sysfs_dirent *dir_sd; + struct kernfs_node *parent; struct attribute *const *attr; - dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name); - if (dir_sd) { + parent = kernfs_find_and_get(kobj->sd, grp->name); + if (parent) { for (attr = grp->attrs; *attr; ++attr) - sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); - sysfs_put(dir_sd); + kernfs_remove_by_name(parent, (*attr)->name); + kernfs_put(parent); } } EXPORT_SYMBOL_GPL(sysfs_unmerge_group); @@ -215,15 +333,15 @@ int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, struct kobject *target, const char *link_name) { - struct sysfs_dirent *dir_sd; + struct kernfs_node *parent; int error = 0; - dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name); - if (!dir_sd) + parent = kernfs_find_and_get(kobj->sd, group_name); + if (!parent) return -ENOENT; - error = sysfs_create_link_sd(dir_sd, target, link_name); - sysfs_put(dir_sd); + error = sysfs_create_link_sd(parent, target, link_name); + kernfs_put(parent); return error; } @@ -238,16 +356,56 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, const char *link_name) { - struct sysfs_dirent *dir_sd; + struct kernfs_node *parent; - dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name); - if (dir_sd) { - sysfs_hash_and_remove(dir_sd, NULL, link_name); - sysfs_put(dir_sd); + parent = kernfs_find_and_get(kobj->sd, group_name); + if (parent) { + kernfs_remove_by_name(parent, link_name); + kernfs_put(parent); } } EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group); -EXPORT_SYMBOL_GPL(sysfs_create_group); -EXPORT_SYMBOL_GPL(sysfs_update_group); -EXPORT_SYMBOL_GPL(sysfs_remove_group); +/** + * __compat_only_sysfs_link_entry_to_kobj - add a symlink to a kobject pointing + * to a group or an attribute + * @kobj: The kobject containing the group. + * @target_kobj: The target kobject. + * @target_name: The name of the target group or attribute. + */ +int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj, + struct kobject *target_kobj, + const char *target_name) +{ + struct kernfs_node *target; + struct kernfs_node *entry; + struct kernfs_node *link; + + /* + * We don't own @target_kobj and it may be removed at any time. + * Synchronize using sysfs_symlink_target_lock. See sysfs_remove_dir() + * for details. + */ + spin_lock(&sysfs_symlink_target_lock); + target = target_kobj->sd; + if (target) + kernfs_get(target); + spin_unlock(&sysfs_symlink_target_lock); + if (!target) + return -ENOENT; + + entry = kernfs_find_and_get(target_kobj->sd, target_name); + if (!entry) { + kernfs_put(target); + return -ENOENT; + } + + link = kernfs_create_link(kobj->sd, target_name, entry); + if (IS_ERR(link) && PTR_ERR(link) == -EEXIST) + sysfs_warn_dup(kobj->sd, target_name); + + kernfs_put(entry); + kernfs_put(target); + return IS_ERR(link) ? PTR_ERR(link) : 0; +} +EXPORT_SYMBOL_GPL(__compat_only_sysfs_link_entry_to_kobj);