Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm

[~andy/linux] / fs / sysfs / symlink.c

diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index fae57c83a722f4e782a2651e7dc0b74a66dfee76..f50e3cc2ded8d76e00d203829108b40647f1fc63 100644 (file)
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -3,6 +3,7 @@
  */
 
 #include <linux/fs.h>
+#include <linux/mount.h>
 #include <linux/module.h>
 #include <linux/kobject.h>
 #include <linux/namei.h>
@@ -66,6 +67,7 @@ static int sysfs_add_link(struct dentry * parent, const char * name, struct kobj
        if (!error)
                return 0;
 
+       kobject_put(target);
        kfree(sl->link_name);
 exit2:
        kfree(sl);
@@ -81,14 +83,24 @@ exit1:
  */
 int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
 {
-       struct dentry * dentry = kobj->dentry;
-       int error = 0;
+       struct dentry *dentry = NULL;
+       int error = -EEXIST;
+
+       BUG_ON(!name);
+
+       if (!kobj) {
+               if (sysfs_mount && sysfs_mount->mnt_sb)
+                       dentry = sysfs_mount->mnt_sb->s_root;
+       } else
+               dentry = kobj->dentry;
 
-       BUG_ON(!kobj || !kobj->dentry || !name);
+       if (!dentry)
+               return -EFAULT;
 
-       down(&dentry->d_inode->i_sem);
-       error = sysfs_add_link(dentry, name, target);
-       up(&dentry->d_inode->i_sem);
+       mutex_lock(&dentry->d_inode->i_mutex);
+       if (!sysfs_dirent_exist(dentry->d_fsdata, name))
+               error = sysfs_add_link(dentry, name, target);
+       mutex_unlock(&dentry->d_inode->i_mutex);
        return error;
 }
 
@@ -151,17 +163,17 @@ static int sysfs_getlink(struct dentry *dentry, char * path)
 
 }
 
-static int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
        int error = -ENOMEM;
        unsigned long page = get_zeroed_page(GFP_KERNEL);
        if (page)
                error = sysfs_getlink(dentry, (char *) page); 
        nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);
-       return 0;
+       return NULL;
 }
 
-static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd)
+static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
 {
        char *page = nd_get_link(nd);
        if (!IS_ERR(page))
@@ -177,4 +189,3 @@ struct inode_operations sysfs_symlink_inode_operations = {
 
 EXPORT_SYMBOL_GPL(sysfs_create_link);
 EXPORT_SYMBOL_GPL(sysfs_remove_link);
-