Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
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>
  • Loading branch information...
commit 79714f72d3b964611997de512cb29198c9f2dbbb 1 parent 1acf0af
Al Viro authored
View
98 drivers/base/devtmpfs.c
@@ -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)) {
- if (dentry->d_inode) {
- if (dentry->d_inode->i_private == &thread)
- err = vfs_rmdir(nd.path.dentry->d_inode,
- dentry);
- else
- err = -EPERM;
- } else {
- err = -ENOENT;
- }
- dput(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(parent.dentry->d_inode, dentry);
+ else
+ err = -EPERM;
} else {
- err = PTR_ERR(dentry);
+ err = -ENOENT;
}
-
- mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
- path_put(&nd.path);
+ dput(dentry);
+ mutex_unlock(&parent.dentry->d_inode->i_mutex);
+ path_put(&parent);
return err;
}
@@ -305,50 +296,43 @@ 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);
- if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {
- struct iattr newattrs;
- /*
- * before unlinking this node, reset permissions
- * of possible references like hardlinks
- */
- newattrs.ia_uid = 0;
- newattrs.ia_gid = 0;
- newattrs.ia_mode = stat.mode & ~0777;
- newattrs.ia_valid =
- ATTR_UID|ATTR_GID|ATTR_MODE;
- 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);
- if (!err || err == -ENOENT)
- deleted = 1;
- }
- } else {
- err = -ENOENT;
+ if (dentry->d_inode) {
+ struct kstat stat;
+ err = vfs_getattr(parent.mnt, dentry, &stat);
+ if (!err && dev_mynode(dev, dentry->d_inode, &stat)) {
+ struct iattr newattrs;
+ /*
+ * before unlinking this node, reset permissions
+ * of possible references like hardlinks
+ */
+ newattrs.ia_uid = 0;
+ newattrs.ia_gid = 0;
+ newattrs.ia_mode = stat.mode & ~0777;
+ newattrs.ia_valid =
+ ATTR_UID|ATTR_GID|ATTR_MODE;
+ mutex_lock(&dentry->d_inode->i_mutex);
+ notify_change(dentry, &newattrs);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+ err = vfs_unlink(parent.dentry->d_inode, dentry);
+ if (!err || err == -ENOENT)
+ deleted = 1;
}
- dput(dentry);
} else {
- err = PTR_ERR(dentry);
+ err = -ENOENT;
}
- mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+ dput(dentry);
+ mutex_unlock(&parent.dentry->d_inode->i_mutex);
- path_put(&nd.path);
+ path_put(&parent);
if (deleted && strchr(nodename, '/'))
delete_path(nodename);
return err;
View
22 fs/namei.c
@@ -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)
View
2  include/linux/namei.h
@@ -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 *);
View
25 kernel/audit_watch.c
@@ -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;
}
Please sign in to comment.
Something went wrong with that request. Please try again.