From: Al Viro Signed-off-by: Al Viro --- fs/debugfs/inode.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/debugfs.h | 5 +++++ 2 files changed, 53 insertions(+) diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 1219dff8e18f..957c40ce09f6 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -175,6 +175,18 @@ static const struct super_operations debugfs_super_operations = { .show_options = debugfs_show_options, }; +static struct vfsmount *debugfs_automount(struct path *path) +{ + struct vfsmount *(*f)(void *); + f = (struct vfsmount *(*)(void *))path->dentry->d_fsdata; + return f(path->dentry->d_inode->i_private); +} + +static const struct dentry_operations debugfs_dops = { + .d_delete = always_delete_dentry, + .d_automount = debugfs_automount, +}; + static int debug_fill_super(struct super_block *sb, void *data, int silent) { static struct tree_descr debug_files[] = {{""}}; @@ -199,6 +211,7 @@ static int debug_fill_super(struct super_block *sb, void *data, int silent) goto fail; sb->s_op = &debugfs_super_operations; + sb->s_d_op = &debugfs_dops; debugfs_apply_options(sb); @@ -368,6 +381,41 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) EXPORT_SYMBOL_GPL(debugfs_create_dir); /** + * debugfs_create_automount - create automount point in the debugfs filesystem + * @name: a pointer to a string containing the name of the file to create. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * file will be created in the root of the debugfs filesystem. + * @f: function to be called when pathname resolution steps on that one. + * @data: opaque argument to pass to f(). + * + * @f should return what ->d_automount() would. + */ +struct dentry *debugfs_create_automount(const char *name, + struct dentry *parent, + struct vfsmount *(*f)(void *), + void *data) +{ + struct dentry *dentry = start_creating(name, parent); + struct inode *inode; + + if (IS_ERR(dentry)) + return NULL; + + inode = debugfs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); + + inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; + inode->i_flags |= S_AUTOMOUNT; + inode->i_private = data; + dentry->d_fsdata = (void *)f; + d_instantiate(dentry, inode); + return end_creating(dentry); +} +EXPORT_SYMBOL(debugfs_create_automount); + +/** * debugfs_create_symlink- create a symbolic link in the debugfs filesystem * @name: a pointer to a string containing the name of the symbolic link to * create. diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h index da4c4983adbe..ea149a24a1f2 100644 --- a/include/linux/debugfs.h +++ b/include/linux/debugfs.h @@ -56,6 +56,11 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent); struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, const char *dest); +struct dentry *debugfs_create_automount(const char *name, + struct dentry *parent, + struct vfsmount *(*f)(void *), + void *data); + void debugfs_remove(struct dentry *dentry); void debugfs_remove_recursive(struct dentry *dentry); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/