/* * fs/sysfs/symlink.c - sysfs symlink implementation * * Copyright (c) 2001-3 Patrick Mochel * Copyright (c) 2007 SUSE Linux Products GmbH * Copyright (c) 2007 Tejun Heo * * This file is released under the GPLv2. * * Please see Documentation/filesystems/sysfs.txt for more information. */ #include #include #include #include #include #include "sysfs.h" static int sysfs_do_create_link_sd(struct kernfs_node *parent, struct kobject *target_kobj, const char *name, int warn) { struct kernfs_node *kn, *target = NULL; BUG_ON(!name || !parent); /* * 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); if (target_kobj->sd) { target = target_kobj->sd; kernfs_get(target); } spin_unlock(&sysfs_symlink_target_lock); if (!target) return -ENOENT; kn = kernfs_create_link(parent, name, target); kernfs_put(target); if (!IS_ERR(kn)) return 0; if (warn && PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, name); return PTR_ERR(kn); } /** * sysfs_create_link_sd - create symlink to a given object. * @kn: directory we're creating the link in. * @target: object we're pointing to. * @name: name of the symlink. */ int sysfs_create_link_sd(struct kernfs_node *kn, struct kobject *target, const char *name) { return sysfs_do_create_link_sd(kn, target, name, 1); } static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target, const char *name, int warn) { struct kernfs_node *parent = NULL; if (!kobj) parent = sysfs_root_kn; else parent = kobj->sd; if (!parent) return -EFAULT; return sysfs_do_create_link_sd(parent, target, name, warn); } /** * sysfs_create_link - create symlink between two objects. * @kobj: object whose directory we're creating the link in. * @target: object we're pointing to. * @name: name of the symlink. */ int sysfs_create_link(struct kobject *kobj, struct kobject *target, const char *name) { return sysfs_do_create_link(kobj, target, name, 1); } EXPORT_SYMBOL_GPL(sysfs_create_link); /** * sysfs_create_link_nowarn - create symlink between two objects. * @kobj: object whose directory we're creating the link in. * @target: object we're pointing to. * @name: name of the symlink. * * This function does the same as sysfs_create_link(), but it * doesn't warn if the link already exists. */ int sysfs_create_link_nowarn(struct kobject *kobj, struct kobject *target, const char *name) { return sysfs_do_create_link(kobj, target, name, 0); } /** * sysfs_delete_link - remove symlink in object's directory. * @kobj: object we're acting for. * @targ: object we're pointing to. * @name: name of the symlink to remove. * * Unlike sysfs_remove_link sysfs_delete_link has enough information * to successfully delete symlinks in tagged directories. */ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, const char *name) { const void *ns = NULL; /* * We don't own @target 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); if (targ->sd && kernfs_ns_enabled(kobj->sd)) ns = targ->sd->ns; spin_unlock(&sysfs_symlink_target_lock); kernfs_remove_by_name_ns(kobj->sd, name, ns); } /** * sysfs_remove_link - remove symlink in object's directory. * @kobj: object we're acting for. * @name: name of the symlink to remove. */ void sysfs_remove_link(struct kobject *kobj, const char *name) { struct kernfs_node *parent = NULL; if (!kobj) parent = sysfs_root_kn; else parent = kobj->sd; kernfs_remove_by_name(parent, name); } EXPORT_SYMBOL_GPL(sysfs_remove_link); /** * sysfs_rename_link_ns - rename symlink in object's directory. * @kobj: object we're acting for. * @targ: object we're pointing to. * @old: previous name of the symlink. * @new: new name of the symlink. * @new_ns: new namespace of the symlink. * * A helper function for the common rename symlink idiom. */ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ, const char *old, const char *new, const void *new_ns) { struct kernfs_node *parent, *kn = NULL; const void *old_ns = NULL; int result; if (!kobj) parent = sysfs_root_kn; else parent = kobj->sd; if (targ->sd) old_ns = targ->sd->ns; result = -ENOENT; kn = kernfs_find_and_get_ns(parent, old, old_ns); if (!kn) goto out; result = -EINVAL; if (kernfs_type(kn) != KERNFS_LINK) goto out; if (kn->symlink.target_kn->priv != targ) goto out; result = kernfs_rename_ns(kn, parent, new, new_ns); out: kernfs_put(kn); return result; } EXPORT_SYMBOL_GPL(sysfs_rename_link_ns); >
authorStanislaw Gruszka <sgruszka@redhat.com>2017-01-29 12:40:52 +0100
committerKalle Valo <kvalo@codeaurora.org>2017-01-31 09:08:52 +0200
commit33e962c8871f015f5c8978384553dddcf5b81b22 (patch)
tree43aff96c2ee21d9e0fa2018457778a4de52053cd /tools/build/Makefile.feature
parent575ddce0507789bf9830d089557d2199d2f91865 (diff)
rt2x00: fix clk_get call
clk_get() takes two arguments and might return ERR_PTR(), so we have to nullify pointer on that case, to do not break further call to clk_get_rate(). Reported-by: Felix Fietkau <nbd@nbd.name> Fixes: 34db70b92fae ("rt2x00: add copy of clk for soc devices") Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Diffstat (limited to 'tools/build/Makefile.feature')