Revert "sysfs: Kill nlink counting."

This reverts commit 524b6c5b39b931311dfe5a2f5abae2f5c9731676.

It has shown to break userspace tools, which is not acceptable.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 10 insertions, 0 deletions

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index dd3779cf3a3b..2a7a3f5d1ca6 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -91,6 +91,9 @@ static int sysfs_link_sibling(struct sysfs_dirent *sd)
         struct rb_node **node = &sd->s_parent->s_dir.children.rb_node;
         struct rb_node *parent = NULL;
 
+        if (sysfs_type(sd) == SYSFS_DIR)
+                sd->s_parent->s_dir.subdirs++;
+
         while (*node) {
                 struct sysfs_dirent *pos;
                 int result;
@@ -123,6 +126,9 @@ static int sysfs_link_sibling(struct sysfs_dirent *sd)
  */
 static void sysfs_unlink_sibling(struct sysfs_dirent *sd)
 {
+        if (sysfs_type(sd) == SYSFS_DIR)
+                sd->s_parent->s_dir.subdirs--;
+
         rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children);
 }
 
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index cc7ea5de2fdd..feb2d69396cf 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -217,6 +217,9 @@ static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode)
                                             iattrs->ia_secdata,
                                             iattrs->ia_secdata_len);
         }
+
+        if (sysfs_type(sd) == SYSFS_DIR)
+                set_nlink(inode, sd->s_dir.subdirs + 2);
 }
 
 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 6289a00287db..661a9639570b 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -19,6 +19,7 @@ struct sysfs_open_dirent;
 struct sysfs_elem_dir {
         struct kobject          *kobj;
 
+        unsigned long           subdirs;
         /* children rbtree starts here and goes through sd->s_rb */
         struct rb_root          children;
 };