Commit 79714f72 authored by Al Viro's avatar Al Viro
Browse files

get rid of kern_path_parent() 

all callers want the same thing, actually - a kinda-sorta analog of
kern_path_create().  I.e. they want parent vfsmount/dentry (with
->i_mutex held, to make sure the child dentry is still their child)
+ the child dentry.

Signed-off-by Al Viro <viro@zeniv.linux.org.uk>
parent 1acf0af9

drivers/base/devtmpfs.c

+41 −57
Original line number Diff line number Diff line
@@ -227,33 +227,24 @@ static int handle_create(const char *nodename, umode_t mode, struct device *dev) 


static int dev_rmdir(const char *name)

{

	struct nameidata nd;

	struct path parent;

	struct dentry *dentry;

	int err;



	err = kern_path_parent(name, &nd);

	if (err)

		return err;



	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);

	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);

	if (!IS_ERR(dentry)) {

	dentry = kern_path_locked(name, &parent);

	if (IS_ERR(dentry))

		return PTR_ERR(dentry);

	if (dentry->d_inode) {

		if (dentry->d_inode->i_private == &thread)

				err = vfs_rmdir(nd.path.dentry->d_inode,

						dentry);

			err = vfs_rmdir(parent.dentry->d_inode, dentry);

		else

			err = -EPERM;

	} else {

		err = -ENOENT;

	}

	dput(dentry);

	} else {

		err = PTR_ERR(dentry);

	}



	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

	path_put(&nd.path);

	mutex_unlock(&parent.dentry->d_inode->i_mutex);

	path_put(&parent);

	return err;

}
@@ -305,21 +296,18 @@ static int dev_mynode(struct device *dev, struct inode *inode, struct kstat *sta 


static int handle_remove(const char *nodename, struct device *dev)

{

	struct nameidata nd;

	struct path parent;

	struct dentry *dentry;

	struct kstat stat;

	int deleted = 1;

	int err;



	err = kern_path_parent(nodename, &nd);

	if (err)

		return err;

	dentry = kern_path_locked(nodename, &parent);

	if (IS_ERR(dentry))

		return PTR_ERR(dentry);



	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);

	dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);

	if (!IS_ERR(dentry)) {

	if (dentry->d_inode) {

			err = vfs_getattr(nd.path.mnt, dentry, &stat);

		struct kstat stat;

		err = vfs_getattr(parent.mnt, dentry, &stat);

		if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {

			struct iattr newattrs;

			/*
@@ -334,8 +322,7 @@ static int handle_remove(const char *nodename, struct device *dev) 
			mutex_lock(&dentry->d_inode->i_mutex);

			notify_change(dentry, &newattrs);

			mutex_unlock(&dentry->d_inode->i_mutex);

				err = vfs_unlink(nd.path.dentry->d_inode,

						 dentry);

			err = vfs_unlink(parent.dentry->d_inode, dentry);

			if (!err || err == -ENOENT)

				deleted = 1;

		}
@@ -343,12 +330,9 @@ static int handle_remove(const char *nodename, struct device *dev) 
		err = -ENOENT;

	}

	dput(dentry);

	} else {

		err = PTR_ERR(dentry);

	}

	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

	mutex_unlock(&parent.dentry->d_inode->i_mutex);



	path_put(&nd.path);

	path_put(&parent);

	if (deleted && strchr(nodename, '/'))

		delete_path(nodename);

	return err;

fs/namei.c

+20 −2
Original line number Diff line number Diff line
@@ -1814,9 +1814,27 @@ static int do_path_lookup(int dfd, const char *name, 
	return retval;

}



int kern_path_parent(const char *name, struct nameidata *nd)

/* does lookup, returns the object with parent locked */

struct dentry *kern_path_locked(const char *name, struct path *path)

{

	return do_path_lookup(AT_FDCWD, name, LOOKUP_PARENT, nd);

	struct nameidata nd;

	struct dentry *d;

	int err = do_path_lookup(AT_FDCWD, name, LOOKUP_PARENT, &nd);

	if (err)

		return ERR_PTR(err);

	if (nd.last_type != LAST_NORM) {

		path_put(&nd.path);

		return ERR_PTR(-EINVAL);

	}

	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);

	d = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);

	if (IS_ERR(d)) {

		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

		path_put(&nd.path);

		return d;

	}

	*path = nd.path;

	return d;

}



int kern_path(const char *name, unsigned int flags, struct path *path)

include/linux/namei.h

+1 −1
Original line number Diff line number Diff line
@@ -67,7 +67,7 @@ extern int kern_path(const char *, unsigned, struct path *); 


extern struct dentry *kern_path_create(int, const char *, struct path *, int);

extern struct dentry *user_path_create(int, const char __user *, struct path *, int);

extern int kern_path_parent(const char *, struct nameidata *);

extern struct dentry *kern_path_locked(const char *, struct path *);

extern int vfs_path_lookup(struct dentry *, struct vfsmount *,

			   const char *, unsigned int, struct path *);

kernel/audit_watch.c

+3 −22
Original line number Diff line number Diff line
@@ -355,34 +355,15 @@ static void audit_remove_parent_watches(struct audit_parent *parent) 
/* Get path information necessary for adding watches. */

static int audit_get_nd(struct audit_watch *watch, struct path *parent)

{

	struct nameidata nd;

	struct dentry *d;

	int err;



	err = kern_path_parent(watch->path, &nd);

	if (err)

		return err;



	if (nd.last_type != LAST_NORM) {

		path_put(&nd.path);

		return -EINVAL;

	}



	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);

	d = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);

	if (IS_ERR(d)) {

		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);

		path_put(&nd.path);

	struct dentry *d = kern_path_locked(watch->path, parent);

	if (IS_ERR(d))

		return PTR_ERR(d);

	}

	mutex_unlock(&parent->dentry->d_inode->i_mutex);

	if (d->d_inode) {

		/* update watch filter fields */

		watch->dev = d->d_inode->i_sb->s_dev;

		watch->ino = d->d_inode->i_ino;

	}

	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);



	*parent = nd.path;

	dput(d);

	return 0;

}

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