Commit 37c1c04c authored by Jarkko Sakkinen's avatar Jarkko Sakkinen Committed by Peter Huewe
Browse files

sysfs: added __compat_only_sysfs_link_entry_to_kobj() 



Added a new function __compat_only_sysfs_link_group_to_kobj() that adds
a symlink from attribute or group to a kobject. This needed for
maintaining backwards compatibility with PPI attributes in the TPM
driver.

Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: default avatarPeter Huewe <peterhuewe@gmx.de>
parent 399235dc

fs/sysfs/group.c

+44 −0
Original line number Diff line number Diff line
@@ -352,3 +352,47 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, 
	}

}

EXPORT_SYMBOL_GPL(sysfs_remove_link_from_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);

include/linux/sysfs.h

+11 −0
Original line number Diff line number Diff line
@@ -268,6 +268,9 @@ int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, 
			    struct kobject *target, const char *link_name);

void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,

				  const char *link_name);

int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,

				      struct kobject *target_kobj,

				      const char *target_name);



void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
@@ -451,6 +454,14 @@ static inline void sysfs_remove_link_from_group(struct kobject *kobj, 
{

}



static inline int __compat_only_sysfs_link_entry_to_kobj(

	struct kobject *kobj,

	struct kobject *target_kobj,

	const char *target_name)

{

	return 0;

}



static inline void sysfs_notify(struct kobject *kobj, const char *dir,

				const char *attr)

{

CRA Git | Maintained and supported by SUSTech CRA and CCSE