[PATCH 7/8] debugfs: switch to simplefs inode creation API

The only difference, compared to the pre-existing code, is that symlink
creation now triggers fsnotify_create.  This was a bug in the debugfs
code, since for example vfs_symlink does call fsnotify_create.

Signed-off-by: Emanuele Giuseppe Esposito <[email protected]>
---
 fs/debugfs/inode.c | 144 +++++----------------------------------------
 1 file changed, 15 insertions(+), 129 deletions(-)

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 834b5872ca0d..7a2369373b85 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -294,68 +294,6 @@ struct dentry *debugfs_lookup(const char *name, struct=
 dentry *parent)
 }
 EXPORT_SYMBOL_GPL(debugfs_lookup);
=20
-static struct dentry *start_creating(const char *name, struct dentry *pare=
nt)
-{
-=09struct dentry *dentry;
-=09int error;
-
-=09pr_debug("creating file '%s'\n", name);
-
-=09if (IS_ERR(parent))
-=09=09return parent;
-
-=09error =3D simple_pin_fs(&debugfs, &debug_fs_type);
-=09if (error) {
-=09=09pr_err("Unable to pin filesystem for file '%s'\n", name);
-=09=09return ERR_PTR(error);
-=09}
-
-=09/* If the parent is not specified, we create it in the root.
-=09 * We need the root dentry to do this, which is in the super
-=09 * block. A pointer to that is in the struct vfsmount that we
-=09 * have around.
-=09 */
-=09if (!parent)
-=09=09parent =3D debugfs.mount->mnt_root;
-
-=09inode_lock(d_inode(parent));
-=09if (unlikely(IS_DEADDIR(d_inode(parent))))
-=09=09dentry =3D ERR_PTR(-ENOENT);
-=09else
-=09=09dentry =3D lookup_one_len(name, parent, strlen(name));
-=09if (!IS_ERR(dentry) && d_really_is_positive(dentry)) {
-=09=09if (d_is_dir(dentry))
-=09=09=09pr_err("Directory '%s' with parent '%s' already present!\n",
-=09=09=09       name, parent->d_name.name);
-=09=09else
-=09=09=09pr_err("File '%s' in directory '%s' already present!\n",
-=09=09=09       name, parent->d_name.name);
-=09=09dput(dentry);
-=09=09dentry =3D ERR_PTR(-EEXIST);
-=09}
-
-=09if (IS_ERR(dentry)) {
-=09=09inode_unlock(d_inode(parent));
-=09=09simple_release_fs(&debugfs);
-=09}
-
-=09return dentry;
-}
-
-static struct dentry *failed_creating(struct dentry *dentry)
-{
-=09inode_unlock(d_inode(dentry->d_parent));
-=09dput(dentry);
-=09simple_release_fs(&debugfs);
-=09return ERR_PTR(-ENOMEM);
-}
-
-static struct dentry *end_creating(struct dentry *dentry)
-{
-=09inode_unlock(d_inode(dentry->d_parent));
-=09return dentry;
-}
-
 static struct dentry *__debugfs_create_file(const char *name, umode_t mode=
,
 =09=09=09=09struct dentry *parent, void *data,
 =09=09=09=09const struct file_operations *proxy_fops,
@@ -364,32 +302,17 @@ static struct dentry *__debugfs_create_file(const cha=
r *name, umode_t mode,
 =09struct dentry *dentry;
 =09struct inode *inode;
=20
-=09if (!(mode & S_IFMT))
-=09=09mode |=3D S_IFREG;
-=09BUG_ON(!S_ISREG(mode));
-=09dentry =3D start_creating(name, parent);
-
+=09dentry =3D simplefs_create_file(&debugfs, &debug_fs_type,
+=09=09=09=09      name, mode, parent, data, &inode);
 =09if (IS_ERR(dentry))
 =09=09return dentry;
=20
-=09inode =3D simple_new_inode(dentry->d_sb);
-=09if (unlikely(!inode)) {
-=09=09pr_err("out of free dentries, can not create file '%s'\n",
-=09=09       name);
-=09=09return failed_creating(dentry);
-=09}
-
-=09inode->i_mode =3D mode;
-=09inode->i_private =3D data;
-
 =09inode->i_op =3D &debugfs_file_inode_operations;
 =09inode->i_fop =3D proxy_fops;
 =09dentry->d_fsdata =3D (void *)((unsigned long)real_fops |
 =09=09=09=09DEBUGFS_FSDATA_IS_REAL_FOPS_BIT);
=20
-=09d_instantiate(dentry, inode);
-=09fsnotify_create(d_inode(dentry->d_parent), dentry);
-=09return end_creating(dentry);
+=09return simplefs_finish_dentry(dentry, inode);
 }
=20
 /**
@@ -522,29 +445,16 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_size);
  */
 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
 {
-=09struct dentry *dentry =3D start_creating(name, parent);
+=09struct dentry *dentry;
 =09struct inode *inode;
=20
+=09dentry =3D simplefs_create_dir(&debugfs, &debug_fs_type,
+=09=09=09=09     name, 0755, parent, &inode);
 =09if (IS_ERR(dentry))
 =09=09return dentry;
=20
-=09inode =3D simple_new_inode(dentry->d_sb);
-=09if (unlikely(!inode)) {
-=09=09pr_err("out of free dentries, can not create directory '%s'\n",
-=09=09       name);
-=09=09return failed_creating(dentry);
-=09}
-
-=09inode->i_mode =3D S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
 =09inode->i_op =3D &debugfs_dir_inode_operations;
-=09inode->i_fop =3D &simple_dir_operations;
-
-=09/* directory inodes start off with i_nlink =3D=3D 2 (for "." entry) */
-=09inc_nlink(inode);
-=09d_instantiate(dentry, inode);
-=09inc_nlink(d_inode(dentry->d_parent));
-=09fsnotify_mkdir(d_inode(dentry->d_parent), dentry);
-=09return end_creating(dentry);
+=09return simplefs_finish_dentry(dentry, inode);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_dir);
=20
@@ -564,29 +474,19 @@ struct dentry *debugfs_create_automount(const char *n=
ame,
 =09=09=09=09=09debugfs_automount_t f,
 =09=09=09=09=09void *data)
 {
-=09struct dentry *dentry =3D start_creating(name, parent);
+=09struct dentry *dentry;
 =09struct inode *inode;
=20
+=09dentry =3D simplefs_create_dentry(&debugfs, &debug_fs_type, name, paren=
t,
+=09=09=09=09=09&inode);
 =09if (IS_ERR(dentry))
 =09=09return dentry;
=20
-=09inode =3D simple_new_inode(dentry->d_sb);
-=09if (unlikely(!inode)) {
-=09=09pr_err("out of free dentries, can not create automount '%s'\n",
-=09=09       name);
-=09=09return failed_creating(dentry);
-=09}
-
 =09make_empty_dir_inode(inode);
 =09inode->i_flags |=3D S_AUTOMOUNT;
 =09inode->i_private =3D data;
 =09dentry->d_fsdata =3D (void *)f;
-=09/* directory inodes start off with i_nlink =3D=3D 2 (for "." entry) */
-=09inc_nlink(inode);
-=09d_instantiate(dentry, inode);
-=09inc_nlink(d_inode(dentry->d_parent));
-=09fsnotify_mkdir(d_inode(dentry->d_parent), dentry);
-=09return end_creating(dentry);
+=09return simplefs_finish_dentry(dentry, inode);
 }
 EXPORT_SYMBOL(debugfs_create_automount);
=20
@@ -618,28 +518,14 @@ struct dentry *debugfs_create_symlink(const char *nam=
e, struct dentry *parent,
 {
 =09struct dentry *dentry;
 =09struct inode *inode;
-=09char *link =3D kstrdup(target, GFP_KERNEL);
-=09if (!link)
-=09=09return ERR_PTR(-ENOMEM);
=20
-=09dentry =3D start_creating(name, parent);
-=09if (IS_ERR(dentry)) {
-=09=09kfree(link);
+=09dentry =3D simplefs_create_symlink(&debugfs, &debug_fs_type,
+=09=09=09=09=09 name, parent, target, &inode);
+=09if (IS_ERR(dentry))
 =09=09return dentry;
-=09}
=20
-=09inode =3D simple_new_inode(dentry->d_sb);
-=09if (unlikely(!inode)) {
-=09=09pr_err("out of free dentries, can not create symlink '%s'\n",
-=09=09       name);
-=09=09kfree(link);
-=09=09return failed_creating(dentry);
-=09}
-=09inode->i_mode =3D S_IFLNK | S_IRWXUGO;
 =09inode->i_op =3D &debugfs_symlink_inode_operations;
-=09inode->i_link =3D link;
-=09d_instantiate(dentry, inode);
-=09return end_creating(dentry);
+=09return simplefs_finish_dentry(dentry, inode);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_symlink);
=20
--=20
2.25.2