// SPDX-License-Identifier: GPL-2.0/* * fs/sysfs/file.c - sysfs regular (text) file 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. */ #include <linux/module.h>#include <linux/kobject.h>#include <linux/slab.h>#include <linux/list.h>#include <linux/mutex.h>#include <linux/seq_file.h>#include <linux/mm.h> #include "sysfs.h" static struct kobject *sysfs_file_kobj(struct kernfs_node *kn){ guard(rcu)(); return rcu_dereference(kn->__parent)->priv;} /* * Determine ktype->sysfs_ops for the given kernfs_node. This function * must be called while holding an active reference. */static const struct sysfs_ops *sysfs_file_ops(struct kernfs_node *kn){ struct kobject *kobj = sysfs_file_kobj(kn); if (kn->flags & KERNFS_LOCKDEP) lockdep_assert_held(kn); return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;} /* * Reads on sysfs are handled through seq_file, which takes care of hairy * details like buffering and seeking. The following function pipes * sysfs_ops->show() result through seq_file. */static int sysfs_kf_seq_show(struct seq_file *sf, void *v){ struct kernfs_open_file *of = sf->private; struct kobject *kobj = sysfs_file_kobj(of->kn); const struct sysfs_ops *ops = sysfs_file_ops(of->kn); ssize_t count; char *buf; if (WARN_ON_ONCE(!ops->show)) return -EINVAL; /* acquire buffer and ensure that it's >= PAGE_SIZE and clear */ count = seq_get_buf(sf, &buf); if (count < PAGE_SIZE) { seq_commit(sf, -1); return 0; } memset(buf, 0, PAGE_SIZE); count = ops->show(kobj, of->kn->priv, buf); if (count < 0) return count; /* * The code works fine with PAGE_SIZE return but it's likely to * indicate truncated result or overflow in normal use cases. */ if (count >= PAGE_SIZE) { WARN(1, "OOB write or bad count %zd at %pS\n", count, ops->show); /* Try to struggle along */ count = PAGE_SIZE - 1; } seq_commit(sf, count); return 0;} static ssize_t sysfs_kf_bin_read(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos){ const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); loff_t size = file_inode(of->file)->i_size; if (!count) return 0; if (size) { if (pos >= size) return 0; if (pos + count > size) count = size - pos; } if (!battr->read) return -EIO; return battr->read(of->file, kobj, battr, buf, pos, count);} /* kernfs read callback for regular sysfs files with pre-alloc */static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos){ const struct sysfs_ops *ops = sysfs_file_ops(of->kn); struct kobject *kobj = sysfs_file_kobj(of->kn); ssize_t len; /* * If buf != of->prealloc_buf, we don't know how * large it is, so cannot safely pass it to ->show */ if (WARN_ON_ONCE(buf != of->prealloc_buf)) return 0; len = ops->show(kobj, of->kn->priv, buf); if (len < 0) return len; if (len >= (ssize_t)PAGE_SIZE) { printk("fill_read_buffer: %pS returned bad count\n", ops->show); len = PAGE_SIZE - 1; } if (pos) { if (len <= pos) return 0; len -= pos; memmove(buf, buf + pos, len); } return min_t(ssize_t, count, len);} /* kernfs write callback for regular sysfs files */static ssize_t sysfs_kf_write(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos){ const struct sysfs_ops *ops = sysfs_file_ops(of->kn); struct kobject *kobj = sysfs_file_kobj(of->kn); if (!count) return 0; return ops->store(kobj, of->kn->priv, buf, count);} /* kernfs write callback for bin sysfs files */static ssize_t sysfs_kf_bin_write(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos){ const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); loff_t size = file_inode(of->file)->i_size; if (size) { if (size <= pos) return -EFBIG; count = min_t(ssize_t, count, size - pos); } if (!count) return 0; if (!battr->write) return -EIO; return battr->write(of->file, kobj, battr, buf, pos, count);} static int sysfs_kf_bin_mmap(struct kernfs_open_file *of, struct vm_area_struct *vma){ const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); return battr->mmap(of->file, kobj, battr, vma);} static loff_t sysfs_kf_bin_llseek(struct kernfs_open_file *of, loff_t offset, int whence){ const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); if (battr->llseek) return battr->llseek(of->file, kobj, battr, offset, whence); else return generic_file_llseek(of->file, offset, whence);} static int sysfs_kf_bin_open(struct kernfs_open_file *of){ const struct bin_attribute *battr = of->kn->priv; if (battr->f_mapping) of->file->f_mapping = battr->f_mapping(); return 0;} void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr){ struct kernfs_node *kn = kobj->sd, *tmp; if (kn && dir) kn = kernfs_find_and_get(kn, dir); else kernfs_get(kn); if (kn && attr) { tmp = kernfs_find_and_get(kn, attr); kernfs_put(kn); kn = tmp; } if (kn) { kernfs_notify(kn); kernfs_put(kn); }}EXPORT_SYMBOL_GPL(sysfs_notify); static const struct kernfs_ops sysfs_file_kfops_empty = {}; static const struct kernfs_ops sysfs_file_kfops_ro = { .seq_show = sysfs_kf_seq_show,}; static const struct kernfs_ops sysfs_file_kfops_wo = { .write = sysfs_kf_write,}; static const struct kernfs_ops sysfs_file_kfops_rw = { .seq_show = sysfs_kf_seq_show, .write = sysfs_kf_write,}; static const struct kernfs_ops sysfs_prealloc_kfops_ro = { .read = sysfs_kf_read, .prealloc = true,}; static const struct kernfs_ops sysfs_prealloc_kfops_wo = { .write = sysfs_kf_write, .prealloc = true,}; static const struct kernfs_ops sysfs_prealloc_kfops_rw = { .read = sysfs_kf_read, .write = sysfs_kf_write, .prealloc = true,}; static const struct kernfs_ops sysfs_bin_kfops_ro = { .read = sysfs_kf_bin_read,}; static const struct kernfs_ops sysfs_bin_kfops_wo = { .write = sysfs_kf_bin_write,}; static const struct kernfs_ops sysfs_bin_kfops_rw = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write,}; static const struct kernfs_ops sysfs_bin_kfops_mmap = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write, .mmap = sysfs_kf_bin_mmap, .open = sysfs_kf_bin_open, .llseek = sysfs_kf_bin_llseek,}; int sysfs_add_file_mode_ns(struct kernfs_node *parent, const struct attribute *attr, umode_t mode, kuid_t uid, kgid_t gid, const struct ns_common *ns){ struct kobject *kobj = parent->priv; const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops; struct lock_class_key *key = NULL; const struct kernfs_ops *ops = NULL; struct kernfs_node *kn; /* every kobject with an attribute needs a ktype assigned */ if (WARN(!sysfs_ops, KERN_ERR "missing sysfs attribute operations for kobject: %s\n", kobject_name(kobj))) return -EINVAL; if (mode & SYSFS_PREALLOC) { if (sysfs_ops->show && sysfs_ops->store) ops = &sysfs_prealloc_kfops_rw; else if (sysfs_ops->show) ops = &sysfs_prealloc_kfops_ro; else if (sysfs_ops->store) ops = &sysfs_prealloc_kfops_wo; } else { if (sysfs_ops->show && sysfs_ops->store) ops = &sysfs_file_kfops_rw; else if (sysfs_ops->show) ops = &sysfs_file_kfops_ro; else if (sysfs_ops->store) ops = &sysfs_file_kfops_wo; } if (!ops) ops = &sysfs_file_kfops_empty; #ifdef CONFIG_DEBUG_LOCK_ALLOC if (!attr->ignore_lockdep) key = attr->key ?: (struct lock_class_key *)&attr->skey;#endif kn = __kernfs_create_file(parent, attr->name, mode & 0777, uid, gid, PAGE_SIZE, ops, (void *)attr, ns, key); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, attr->name); return PTR_ERR(kn); } return 0;} int sysfs_add_bin_file_mode_ns(struct kernfs_node *parent, const struct bin_attribute *battr, umode_t mode, size_t size, kuid_t uid, kgid_t gid, const struct ns_common *ns){ const struct attribute *attr = &battr->attr; struct lock_class_key *key = NULL; const struct kernfs_ops *ops; struct kernfs_node *kn; if (battr->mmap) ops = &sysfs_bin_kfops_mmap; else if (battr->read && battr->write) ops = &sysfs_bin_kfops_rw; else if (battr->read) ops = &sysfs_bin_kfops_ro; else if (battr->write) ops = &sysfs_bin_kfops_wo; else ops = &sysfs_file_kfops_empty; #ifdef CONFIG_DEBUG_LOCK_ALLOC if (!attr->ignore_lockdep) key = attr->key ?: (struct lock_class_key *)&attr->skey;#endif kn = __kernfs_create_file(parent, attr->name, mode & 0777, uid, gid, size, ops, (void *)attr, ns, key); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, attr->name); return PTR_ERR(kn); } return 0;} /** * sysfs_create_file_ns - create an attribute file for an object with custom ns * @kobj: object we're creating for * @attr: attribute descriptor * @ns: namespace the new file should belong to */int sysfs_create_file_ns(struct kobject *kobj, const struct attribute *attr, const struct ns_common *ns){ kuid_t uid; kgid_t gid; if (WARN_ON(!kobj || !kobj->sd || !attr)) return -EINVAL; kobject_get_ownership(kobj, &uid, &gid); return sysfs_add_file_mode_ns(kobj->sd, attr, attr->mode, uid, gid, ns);}EXPORT_SYMBOL_GPL(sysfs_create_file_ns); int sysfs_create_files(struct kobject *kobj, const struct attribute * const *ptr){ int err = 0; int i; for (i = 0; ptr[i] && !err; i++) err = sysfs_create_file(kobj, ptr[i]); if (err) while (--i >= 0) sysfs_remove_file(kobj, ptr[i]); return err;}EXPORT_SYMBOL_GPL(sysfs_create_files); /** * sysfs_add_file_to_group - add an attribute file to a pre-existing group. * @kobj: object we're acting for. * @attr: attribute descriptor. * @group: group name. */int sysfs_add_file_to_group(struct kobject *kobj, const struct attribute *attr, const char *group){ struct kernfs_node *parent; kuid_t uid; kgid_t gid; int error; if (group) { parent = kernfs_find_and_get(kobj->sd, group); } else { parent = kobj->sd; kernfs_get(parent); } if (!parent) return -ENOENT; kobject_get_ownership(kobj, &uid, &gid); error = sysfs_add_file_mode_ns(parent, attr, attr->mode, uid, gid, NULL); kernfs_put(parent); return error;}EXPORT_SYMBOL_GPL(sysfs_add_file_to_group); /** * sysfs_chmod_file - update the modified mode value on an object attribute. * @kobj: object we're acting for. * @attr: attribute descriptor. * @mode: file permissions. * */int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr, umode_t mode){ struct kernfs_node *kn; struct iattr newattrs; int rc; kn = kernfs_find_and_get(kobj->sd, attr->name); if (!kn) return -ENOENT; newattrs.ia_mode = (mode & S_IALLUGO) | (kn->mode & ~S_IALLUGO); newattrs.ia_valid = ATTR_MODE; rc = kernfs_setattr(kn, &newattrs); kernfs_put(kn); return rc;}EXPORT_SYMBOL_GPL(sysfs_chmod_file); /** * sysfs_break_active_protection - break "active" protection * @kobj: The kernel object @attr is associated with. * @attr: The attribute to break the "active" protection for. * * With sysfs, just like kernfs, deletion of an attribute is postponed until * all active .show() and .store() callbacks have finished unless this function * is called. Hence this function is useful in methods that implement self * deletion. */struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj, const struct attribute *attr){ struct kernfs_node *kn; kobject_get(kobj); kn = kernfs_find_and_get(kobj->sd, attr->name); if (kn) kernfs_break_active_protection(kn); else kobject_put(kobj); return kn;}EXPORT_SYMBOL_GPL(sysfs_break_active_protection); /** * sysfs_unbreak_active_protection - restore "active" protection * @kn: Pointer returned by sysfs_break_active_protection(). * * Undo the effects of sysfs_break_active_protection(). Since this function * calls kernfs_put() on the kernfs node that corresponds to the 'attr' * argument passed to sysfs_break_active_protection() that attribute may have * been removed between the sysfs_break_active_protection() and * sysfs_unbreak_active_protection() calls, it is not safe to access @kn after * this function has returned. */void sysfs_unbreak_active_protection(struct kernfs_node *kn){ struct kobject *kobj = sysfs_file_kobj(kn); kernfs_unbreak_active_protection(kn); kernfs_put(kn); kobject_put(kobj);}EXPORT_SYMBOL_GPL(sysfs_unbreak_active_protection);Lines 1–500 of 821. Load more
// SPDX-License-Identifier: GPL-2.0 /* * fs/sysfs/file.c - sysfs regular (text) file 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. */ #include <linux/module.h> #include <linux/kobject.h> #include <linux/slab.h> #include <linux/list.h> #include <linux/mutex.h> #include <linux/seq_file.h> #include <linux/mm.h> #include "sysfs.h" static struct kobject *sysfs_file_kobj(struct kernfs_node *kn) { guard(rcu)(); return rcu_dereference(kn->__parent)->priv; } /* * Determine ktype->sysfs_ops for the given kernfs_node. This function * must be called while holding an active reference. */ static const struct sysfs_ops *sysfs_file_ops(struct kernfs_node *kn) { struct kobject *kobj = sysfs_file_kobj(kn); if (kn->flags & KERNFS_LOCKDEP) lockdep_assert_held(kn); return kobj->ktype ? kobj->ktype->sysfs_ops : NULL; } /* * Reads on sysfs are handled through seq_file, which takes care of hairy * details like buffering and seeking. The following function pipes * sysfs_ops->show() result through seq_file. */ static int sysfs_kf_seq_show(struct seq_file *sf, void *v) { struct kernfs_open_file *of = sf->private; struct kobject *kobj = sysfs_file_kobj(of->kn); const struct sysfs_ops *ops = sysfs_file_ops(of->kn); ssize_t count; char *buf; if (WARN_ON_ONCE(!ops->show)) return -EINVAL; /* acquire buffer and ensure that it's >= PAGE_SIZE and clear */ count = seq_get_buf(sf, &buf); if (count < PAGE_SIZE) { seq_commit(sf, -1); return 0; } memset(buf, 0, PAGE_SIZE); count = ops->show(kobj, of->kn->priv, buf); if (count < 0) return count; /* * The code works fine with PAGE_SIZE return but it's likely to * indicate truncated result or overflow in normal use cases. */ if (count >= PAGE_SIZE) { WARN(1, "OOB write or bad count %zd at %pS\n", count, ops->show); /* Try to struggle along */ count = PAGE_SIZE - 1; } seq_commit(sf, count); return 0; } static ssize_t sysfs_kf_bin_read(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos) { const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); loff_t size = file_inode(of->file)->i_size; if (!count) return 0; if (size) { if (pos >= size) return 0; if (pos + count > size) count = size - pos; } if (!battr->read) return -EIO; return battr->read(of->file, kobj, battr, buf, pos, count); } /* kernfs read callback for regular sysfs files with pre-alloc */ static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos) { const struct sysfs_ops *ops = sysfs_file_ops(of->kn); struct kobject *kobj = sysfs_file_kobj(of->kn); ssize_t len; /* * If buf != of->prealloc_buf, we don't know how * large it is, so cannot safely pass it to ->show */ if (WARN_ON_ONCE(buf != of->prealloc_buf)) return 0; len = ops->show(kobj, of->kn->priv, buf); if (len < 0) return len; if (len >= (ssize_t)PAGE_SIZE) { printk("fill_read_buffer: %pS returned bad count\n", ops->show); len = PAGE_SIZE - 1; } if (pos) { if (len <= pos) return 0; len -= pos; memmove(buf, buf + pos, len); } return min_t(ssize_t, count, len); } /* kernfs write callback for regular sysfs files */ static ssize_t sysfs_kf_write(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos) { const struct sysfs_ops *ops = sysfs_file_ops(of->kn); struct kobject *kobj = sysfs_file_kobj(of->kn); if (!count) return 0; return ops->store(kobj, of->kn->priv, buf, count); } /* kernfs write callback for bin sysfs files */ static ssize_t sysfs_kf_bin_write(struct kernfs_open_file *of, char *buf, size_t count, loff_t pos) { const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); loff_t size = file_inode(of->file)->i_size; if (size) { if (size <= pos) return -EFBIG; count = min_t(ssize_t, count, size - pos); } if (!count) return 0; if (!battr->write) return -EIO; return battr->write(of->file, kobj, battr, buf, pos, count); } static int sysfs_kf_bin_mmap(struct kernfs_open_file *of, struct vm_area_struct *vma) { const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); return battr->mmap(of->file, kobj, battr, vma); } static loff_t sysfs_kf_bin_llseek(struct kernfs_open_file *of, loff_t offset, int whence) { const struct bin_attribute *battr = of->kn->priv; struct kobject *kobj = sysfs_file_kobj(of->kn); if (battr->llseek) return battr->llseek(of->file, kobj, battr, offset, whence); else return generic_file_llseek(of->file, offset, whence); } static int sysfs_kf_bin_open(struct kernfs_open_file *of) { const struct bin_attribute *battr = of->kn->priv; if (battr->f_mapping) of->file->f_mapping = battr->f_mapping(); return 0; } void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr) { struct kernfs_node *kn = kobj->sd, *tmp; if (kn && dir) kn = kernfs_find_and_get(kn, dir); else kernfs_get(kn); if (kn && attr) { tmp = kernfs_find_and_get(kn, attr); kernfs_put(kn); kn = tmp; } if (kn) { kernfs_notify(kn); kernfs_put(kn); } } EXPORT_SYMBOL_GPL(sysfs_notify); static const struct kernfs_ops sysfs_file_kfops_empty = { }; static const struct kernfs_ops sysfs_file_kfops_ro = { .seq_show = sysfs_kf_seq_show, }; static const struct kernfs_ops sysfs_file_kfops_wo = { .write = sysfs_kf_write, }; static const struct kernfs_ops sysfs_file_kfops_rw = { .seq_show = sysfs_kf_seq_show, .write = sysfs_kf_write, }; static const struct kernfs_ops sysfs_prealloc_kfops_ro = { .read = sysfs_kf_read, .prealloc = true, }; static const struct kernfs_ops sysfs_prealloc_kfops_wo = { .write = sysfs_kf_write, .prealloc = true, }; static const struct kernfs_ops sysfs_prealloc_kfops_rw = { .read = sysfs_kf_read, .write = sysfs_kf_write, .prealloc = true, }; static const struct kernfs_ops sysfs_bin_kfops_ro = { .read = sysfs_kf_bin_read, }; static const struct kernfs_ops sysfs_bin_kfops_wo = { .write = sysfs_kf_bin_write, }; static const struct kernfs_ops sysfs_bin_kfops_rw = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write, }; static const struct kernfs_ops sysfs_bin_kfops_mmap = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write, .mmap = sysfs_kf_bin_mmap, .open = sysfs_kf_bin_open, .llseek = sysfs_kf_bin_llseek, }; int sysfs_add_file_mode_ns(struct kernfs_node *parent, const struct attribute *attr, umode_t mode, kuid_t uid, kgid_t gid, const struct ns_common *ns) { struct kobject *kobj = parent->priv; const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops; struct lock_class_key *key = NULL; const struct kernfs_ops *ops = NULL; struct kernfs_node *kn; /* every kobject with an attribute needs a ktype assigned */ if (WARN(!sysfs_ops, KERN_ERR "missing sysfs attribute operations for kobject: %s\n", kobject_name(kobj))) return -EINVAL; if (mode & SYSFS_PREALLOC) { if (sysfs_ops->show && sysfs_ops->store) ops = &sysfs_prealloc_kfops_rw; else if (sysfs_ops->show) ops = &sysfs_prealloc_kfops_ro; else if (sysfs_ops->store) ops = &sysfs_prealloc_kfops_wo; } else { if (sysfs_ops->show && sysfs_ops->store) ops = &sysfs_file_kfops_rw; else if (sysfs_ops->show) ops = &sysfs_file_kfops_ro; else if (sysfs_ops->store) ops = &sysfs_file_kfops_wo; } if (!ops) ops = &sysfs_file_kfops_empty; #ifdef CONFIG_DEBUG_LOCK_ALLOC if (!attr->ignore_lockdep) key = attr->key ?: (struct lock_class_key *)&attr->skey; #endif kn = __kernfs_create_file(parent, attr->name, mode & 0777, uid, gid, PAGE_SIZE, ops, (void *)attr, ns, key); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, attr->name); return PTR_ERR(kn); } return 0; } int sysfs_add_bin_file_mode_ns(struct kernfs_node *parent, const struct bin_attribute *battr, umode_t mode, size_t size, kuid_t uid, kgid_t gid, const struct ns_common *ns) { const struct attribute *attr = &battr->attr; struct lock_class_key *key = NULL; const struct kernfs_ops *ops; struct kernfs_node *kn; if (battr->mmap) ops = &sysfs_bin_kfops_mmap; else if (battr->read && battr->write) ops = &sysfs_bin_kfops_rw; else if (battr->read) ops = &sysfs_bin_kfops_ro; else if (battr->write) ops = &sysfs_bin_kfops_wo; else ops = &sysfs_file_kfops_empty; #ifdef CONFIG_DEBUG_LOCK_ALLOC if (!attr->ignore_lockdep) key = attr->key ?: (struct lock_class_key *)&attr->skey; #endif kn = __kernfs_create_file(parent, attr->name, mode & 0777, uid, gid, size, ops, (void *)attr, ns, key); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, attr->name); return PTR_ERR(kn); } return 0; } /** * sysfs_create_file_ns - create an attribute file for an object with custom ns * @kobj: object we're creating for * @attr: attribute descriptor * @ns: namespace the new file should belong to */ int sysfs_create_file_ns(struct kobject *kobj, const struct attribute *attr, const struct ns_common *ns) { kuid_t uid; kgid_t gid; if (WARN_ON(!kobj || !kobj->sd || !attr)) return -EINVAL; kobject_get_ownership(kobj, &uid, &gid); return sysfs_add_file_mode_ns(kobj->sd, attr, attr->mode, uid, gid, ns); } EXPORT_SYMBOL_GPL(sysfs_create_file_ns); int sysfs_create_files(struct kobject *kobj, const struct attribute * const *ptr) { int err = 0; int i; for (i = 0; ptr[i] && !err; i++) err = sysfs_create_file(kobj, ptr[i]); if (err) while (--i >= 0) sysfs_remove_file(kobj, ptr[i]); return err; } EXPORT_SYMBOL_GPL(sysfs_create_files); /** * sysfs_add_file_to_group - add an attribute file to a pre-existing group. * @kobj: object we're acting for. * @attr: attribute descriptor. * @group: group name. */ int sysfs_add_file_to_group(struct kobject *kobj, const struct attribute *attr, const char *group) { struct kernfs_node *parent; kuid_t uid; kgid_t gid; int error; if (group) { parent = kernfs_find_and_get(kobj->sd, group); } else { parent = kobj->sd; kernfs_get(parent); } if (!parent) return -ENOENT; kobject_get_ownership(kobj, &uid, &gid); error = sysfs_add_file_mode_ns(parent, attr, attr->mode, uid, gid, NULL); kernfs_put(parent); return error; } EXPORT_SYMBOL_GPL(sysfs_add_file_to_group); /** * sysfs_chmod_file - update the modified mode value on an object attribute. * @kobj: object we're acting for. * @attr: attribute descriptor. * @mode: file permissions. * */ int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr, umode_t mode) { struct kernfs_node *kn; struct iattr newattrs; int rc; kn = kernfs_find_and_get(kobj->sd, attr->name); if (!kn) return -ENOENT; newattrs.ia_mode = (mode & S_IALLUGO) | (kn->mode & ~S_IALLUGO); newattrs.ia_valid = ATTR_MODE; rc = kernfs_setattr(kn, &newattrs); kernfs_put(kn); return rc; } EXPORT_SYMBOL_GPL(sysfs_chmod_file); /** * sysfs_break_active_protection - break "active" protection * @kobj: The kernel object @attr is associated with. * @attr: The attribute to break the "active" protection for. * * With sysfs, just like kernfs, deletion of an attribute is postponed until * all active .show() and .store() callbacks have finished unless this function * is called. Hence this function is useful in methods that implement self * deletion. */ struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj, const struct attribute *attr) { struct kernfs_node *kn; kobject_get(kobj); kn = kernfs_find_and_get(kobj->sd, attr->name); if (kn) kernfs_break_active_protection(kn); else kobject_put(kobj); return kn; } EXPORT_SYMBOL_GPL(sysfs_break_active_protection); /** * sysfs_unbreak_active_protection - restore "active" protection * @kn: Pointer returned by sysfs_break_active_protection(). * * Undo the effects of sysfs_break_active_protection(). Since this function * calls kernfs_put() on the kernfs node that corresponds to the 'attr' * argument passed to sysfs_break_active_protection() that attribute may have * been removed between the sysfs_break_active_protection() and * sysfs_unbreak_active_protection() calls, it is not safe to access @kn after * this function has returned. */ void sysfs_unbreak_active_protection(struct kernfs_node *kn) { struct kobject *kobj = sysfs_file_kobj(kn); kernfs_unbreak_active_protection(kn); kernfs_put(kn); kobject_put(kobj); } EXPORT_SYMBOL_GPL(sysfs_unbreak_active_protection);