This function is similar but much simpler to sysfs_get_dentry
returns a sysfs dentry if one curently exists.

This requires less locking the sysfs_get_dentry and which
makes it preferable in some contexts.

Signed-off-by: Eric W. Biederman <[EMAIL PROTECTED]>
---
 fs/sysfs/dir.c |   38 ++++++++++++++++++++++++++++++++++++++
 1 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index cff2b12..3ec9040 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -764,6 +764,44 @@ void sysfs_remove_dir(struct kobject * kobj)
        __sysfs_remove_dir(sd);
 }
 
+/**
+ *     __sysfs_get_dentry - get dentry for the given sysfs_dirent
+ *     @sb: superblock of the dentry to return
+ *     @sd: sysfs_dirent of interest
+ *
+ *     Get dentry for @sd.  Only return a dentry if one currently
+ *     exists.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep)
+ *
+ *     RETURNS:
+ *     Pointer to found dentry on success, NULL on failure.
+ */
+static struct dentry *__sysfs_get_dentry(struct super_block *sb, struct 
sysfs_dirent *sd)
+{
+       struct inode *inode;
+       struct dentry *dentry = NULL;
+
+       inode = ilookup5_nowait(sysfs_sb, sd->s_ino, sysfs_ilookup_test, sd);
+       if (inode && !(inode->i_state & I_NEW)) {
+               struct dentry *alias;
+               spin_lock(&dcache_lock);
+               list_for_each_entry(alias, &inode->i_dentry, d_alias) {
+                       if (!IS_ROOT(alias) && d_unhashed(alias))
+                               continue;
+                       if (alias->d_sb != sb)
+                               continue;
+                       dentry = alias;
+                       dget_locked(dentry);
+                       break;
+               }
+               spin_unlock(&dcache_lock);
+       }
+       iput(inode);
+       return dentry;
+}
+
 int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
 {
        struct sysfs_dirent *sd = kobj->sd;
-- 
1.5.3.rc6.17.g1911

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