Commit 7beafd51 authored by Al Viro's avatar Al Viro
Browse files

convert binfmt_misc 



removals are done with locked_recursive_removal(); switch creations to
simple_start_creating()/d_make_persistent()/simple_done_creating() and
take them to a helper (add_entry()), while we are at it - simpler control
flow that way.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent b85d6b24

fs/binfmt_misc.c

+32 −37
Original line number Diff line number Diff line
@@ -765,14 +765,41 @@ static const struct file_operations bm_entry_operations = { 


/* /register */



/* add to filesystem */

static int add_entry(Node *e, struct super_block *sb)

{

	struct dentry *dentry = simple_start_creating(sb->s_root, e->name);

	struct inode *inode;

	struct binfmt_misc *misc;



	if (IS_ERR(dentry))

		return PTR_ERR(dentry);



	inode = bm_get_inode(sb, S_IFREG | 0644);

	if (unlikely(!inode)) {

		simple_done_creating(dentry);

		return -ENOMEM;

	}



	refcount_set(&e->users, 1);

	e->dentry = dentry;

	inode->i_private = e;

	inode->i_fop = &bm_entry_operations;



	d_make_persistent(dentry, inode);

	misc = i_binfmt_misc(inode);

	write_lock(&misc->entries_lock);

	list_add(&e->list, &misc->entries);

	write_unlock(&misc->entries_lock);

	simple_done_creating(dentry);

	return 0;

}



static ssize_t bm_register_write(struct file *file, const char __user *buffer,

			       size_t count, loff_t *ppos)

{

	Node *e;

	struct inode *inode;

	struct super_block *sb = file_inode(file)->i_sb;

	struct dentry *root = sb->s_root, *dentry;

	struct binfmt_misc *misc;

	int err = 0;

	struct file *f = NULL;
@@ -803,39 +830,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer, 
		e->interp_file = f;

	}



	inode_lock(d_inode(root));

	dentry = lookup_noperm(&QSTR(e->name), root);

	err = PTR_ERR(dentry);

	if (IS_ERR(dentry))

		goto out;



	err = -EEXIST;

	if (d_really_is_positive(dentry))

		goto out2;



	inode = bm_get_inode(sb, S_IFREG | 0644);



	err = -ENOMEM;

	if (!inode)

		goto out2;



	refcount_set(&e->users, 1);

	e->dentry = dget(dentry);

	inode->i_private = e;

	inode->i_fop = &bm_entry_operations;



	d_instantiate(dentry, inode);

	misc = i_binfmt_misc(inode);

	write_lock(&misc->entries_lock);

	list_add(&e->list, &misc->entries);

	write_unlock(&misc->entries_lock);



	err = 0;

out2:

	dput(dentry);

out:

	inode_unlock(d_inode(root));



	err = add_entry(e, sb);

	if (err) {

		if (f)

			filp_close(f, NULL);
@@ -1028,7 +1023,7 @@ static struct file_system_type bm_fs_type = { 
	.name		= "binfmt_misc",

	.init_fs_context = bm_init_fs_context,

	.fs_flags	= FS_USERNS_MOUNT,

	.kill_sb	= kill_litter_super,

	.kill_sb	= kill_anon_super,

};

MODULE_ALIAS_FS("binfmt_misc");