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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162// SPDX-License-Identifier: GPL-2.0/* * fs/sysfs/dir.c - sysfs core and dir operation implementation * * Copyright (c) 2001-3 Patrick Mochel * Copyright (c) 2007 SUSE Linux Products GmbH * Copyright (c) 2007 Tejun Heo <teheo@suse.de> * * Please see Documentation/filesystems/sysfs.rst for more information. */
#define pr_fmt(fmt) "sysfs: " fmt
#include <linux/fs.h>#include <linux/kobject.h>#include <linux/slab.h>#include "sysfs.h"
DEFINE_SPINLOCK(sysfs_symlink_target_lock);
void sysfs_warn_dup(struct kernfs_node *parent, const char *name){ char *buf;
buf = kzalloc(PATH_MAX, GFP_KERNEL); if (buf) kernfs_path(parent, buf, PATH_MAX);
pr_warn("cannot create duplicate filename '%s/%s'\n", buf, name); dump_stack();
kfree(buf);}
/** * sysfs_create_dir_ns - create a directory for an object with a namespace tag * @kobj: object we're creating directory for * @ns: the namespace tag to use */int sysfs_create_dir_ns(struct kobject *kobj, const struct ns_common *ns){ struct kernfs_node *parent, *kn; kuid_t uid; kgid_t gid;
if (WARN_ON(!kobj)) return -EINVAL;
if (kobj->parent) parent = kobj->parent->sd; else parent = sysfs_root_kn;
if (!parent) return -ENOENT;
kobject_get_ownership(kobj, &uid, &gid);
kn = kernfs_create_dir_ns(parent, kobject_name(kobj), 0755, uid, gid, kobj, ns); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, kobject_name(kobj)); return PTR_ERR(kn); }
kobj->sd = kn; return 0;}
/** * sysfs_remove_dir - remove an object's directory. * @kobj: object. * * The only thing special about this is that we remove any files in * the directory before we remove the directory, and we've inlined * what used to be sysfs_rmdir() below, instead of calling separately. */void sysfs_remove_dir(struct kobject *kobj){ struct kernfs_node *kn = kobj->sd;
/* * In general, kobject owner is responsible for ensuring removal * doesn't race with other operations and sysfs doesn't provide any * protection; however, when @kobj is used as a symlink target, the * symlinking entity usually doesn't own @kobj and thus has no * control over removal. @kobj->sd may be removed anytime * and symlink code may end up dereferencing an already freed node. * * sysfs_symlink_target_lock synchronizes @kobj->sd * disassociation against symlink operations so that symlink code * can safely dereference @kobj->sd. */ spin_lock(&sysfs_symlink_target_lock); kobj->sd = NULL; spin_unlock(&sysfs_symlink_target_lock);
if (kn) { WARN_ON_ONCE(kernfs_type(kn) != KERNFS_DIR); kernfs_remove(kn); }}
int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name, const struct ns_common *new_ns){ struct kernfs_node *parent; int ret;
parent = kernfs_get_parent(kobj->sd); ret = kernfs_rename_ns(kobj->sd, parent, new_name, new_ns); kernfs_put(parent); return ret;}
int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, const struct ns_common *new_ns){ struct kernfs_node *kn = kobj->sd; struct kernfs_node *new_parent;
new_parent = new_parent_kobj && new_parent_kobj->sd ? new_parent_kobj->sd : sysfs_root_kn;
return kernfs_rename_ns(kn, new_parent, NULL, new_ns);}
/** * sysfs_create_mount_point - create an always empty directory * @parent_kobj: kobject that will contain this always empty directory * @name: The name of the always empty directory to add */int sysfs_create_mount_point(struct kobject *parent_kobj, const char *name){ struct kernfs_node *kn, *parent = parent_kobj->sd;
kn = kernfs_create_empty_dir(parent, name); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, name); return PTR_ERR(kn); }
return 0;}EXPORT_SYMBOL_GPL(sysfs_create_mount_point);
/** * sysfs_remove_mount_point - remove an always empty directory. * @parent_kobj: kobject that will contain this always empty directory * @name: The name of the always empty directory to remove * */void sysfs_remove_mount_point(struct kobject *parent_kobj, const char *name){ struct kernfs_node *parent = parent_kobj->sd;
kernfs_remove_by_name_ns(parent, name, NULL);}EXPORT_SYMBOL_GPL(sysfs_remove_mount_point);