/*
- * symlink.c - operations for sysfs symlinks.
+ * 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 <teheo@suse.de>
+ *
+ * This file is released under the GPLv2.
+ *
+ * Please see Documentation/filesystems/sysfs.txt for more information.
*/
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/namei.h>
-#include <asm/semaphore.h>
+#include <linux/mutex.h>
#include "sysfs.h"
}
}
-static int sysfs_add_link(struct sysfs_dirent * parent_sd, const char * name,
- struct sysfs_dirent * target_sd)
-{
- struct sysfs_dirent * sd;
-
- sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
- if (!sd)
- return -ENOMEM;
-
- sd->s_elem.symlink.target_sd = target_sd;
- sysfs_attach_dirent(sd, parent_sd, NULL);
- return 0;
-}
-
/**
* sysfs_create_link - create symlink between two objects.
* @kobj: object whose directory we're creating the link in.
{
struct sysfs_dirent *parent_sd = NULL;
struct sysfs_dirent *target_sd = NULL;
- int error = -EEXIST;
+ struct sysfs_dirent *sd = NULL;
+ struct sysfs_addrm_cxt acxt;
+ int error;
BUG_ON(!name);
- if (!kobj) {
- if (sysfs_mount && sysfs_mount->mnt_sb)
- parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
- } else
+ if (!kobj)
+ parent_sd = &sysfs_root;
+ else
parent_sd = kobj->sd;
+ error = -EFAULT;
if (!parent_sd)
- return -EFAULT;
+ goto out_put;
/* target->sd can go away beneath us but is protected with
* sysfs_assoc_lock. Fetch target_sd from it.
target_sd = sysfs_get(target->sd);
spin_unlock(&sysfs_assoc_lock);
+ error = -ENOENT;
if (!target_sd)
- return -ENOENT;
+ goto out_put;
+
+ error = -ENOMEM;
+ sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
+ if (!sd)
+ goto out_put;
- mutex_lock(&parent_sd->s_dentry->d_inode->i_mutex);
- if (!sysfs_find_dirent(parent_sd, name))
- error = sysfs_add_link(parent_sd, name, target_sd);
- mutex_unlock(&parent_sd->s_dentry->d_inode->i_mutex);
+ sd->s_symlink.target_sd = target_sd;
+ target_sd = NULL; /* reference is now owned by the symlink */
+
+ sysfs_addrm_start(&acxt, parent_sd);
+ error = sysfs_add_one(&acxt, sd);
+ sysfs_addrm_finish(&acxt);
if (error)
- sysfs_put(target_sd);
+ goto out_put;
+
+ return 0;
+ out_put:
+ sysfs_put(target_sd);
+ sysfs_put(sd);
return error;
}
{
struct sysfs_dirent *sd = dentry->d_fsdata;
struct sysfs_dirent *parent_sd = sd->s_parent;
- struct sysfs_dirent *target_sd = sd->s_elem.symlink.target_sd;
+ struct sysfs_dirent *target_sd = sd->s_symlink.target_sd;
int error;
- down_read(&sysfs_rename_sem);
+ mutex_lock(&sysfs_mutex);
error = sysfs_get_target_path(parent_sd, target_sd, path);
- up_read(&sysfs_rename_sem);
+ mutex_unlock(&sysfs_mutex);
return error;
}