sysfs: kill unnecessary sysfs_get() in open paths

There's no reason to get an extra reference to sysfs_dirent for an
open file.  Open file has a reference to the dentry which in turn has
a reference to sysfs_dirent.  This is fairly obvious as otherwise open
itself won't be able to access the sysfs_dirent.  Kill the extra
sysfs_get() and matching sysfs_put().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 2 insertions, 8 deletions

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index a819a7e8d74d..e93fe5e2fa41 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -193,9 +193,8 @@ static int open(struct inode * inode, struct file * file)
         mutex_init(&bb->mutex);
         file->private_data = bb;
 
-        /* open succeeded, put active reference and pin attr_sd */
+        /* open succeeded, put active reference */
         sysfs_put_active(attr_sd);
-        sysfs_get(attr_sd);
         return 0;
 
  err_out:
@@ -211,7 +210,6 @@ static int release(struct inode * inode, struct file * file)
 
         if (bb->mmapped)
                 sysfs_put_active_two(attr_sd);
-        sysfs_put(attr_sd);
         kfree(bb->buffer);
         kfree(bb);
         return 0;
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 61a8c19df7c3..73333dc68545 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -298,9 +298,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
         buffer->ops = ops;
         file->private_data = buffer;
 
-        /* open succeeded, put active references and pin attr_sd */
+        /* open succeeded, put active references */
         sysfs_put_active_two(attr_sd);
-        sysfs_get(attr_sd);
         return 0;
 
  err_out:
@@ -310,11 +309,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
 
 static int sysfs_release(struct inode * inode, struct file * filp)
 {
-        struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
         struct sysfs_buffer *buffer = filp->private_data;
 
-        sysfs_put(attr_sd);
-
         if (buffer) {
                 if (buffer->page)
                         free_page((unsigned long)buffer->page);