sysfs: make directory dentries and inodes reclaimable

This patch makes dentries and inodes for sysfs directories
reclaimable.

* sysfs_notify() is modified to walk sysfs_dirent tree instead of
  dentry tree.

* sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to
  grab the victim dentry.

* sysfs_rename_dir() and sysfs_move_dir() grab all dentries using
  sysfs_get_dentry() on startup.

* Dentries for all shadowed directories are pinned in memory to serve
  as lookup start point.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 078537e5d696..402cc356203c 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -24,7 +24,7 @@ static const struct super_operations sysfs_ops = {
         .drop_inode     = sysfs_delete_inode,
 };
 
-static struct sysfs_dirent sysfs_root = {
+struct sysfs_dirent sysfs_root = {
         .s_count        = ATOMIC_INIT(1),
         .s_flags        = SYSFS_ROOT,
         .s_mode         = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,