'\" t
.\"     Title: d_obtain_root
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: September 2017
.\"    Manual: The Linux VFS
.\"    Source: Kernel Hackers Manual 4.12.13
.\"  Language: English
.\"
.TH "D_OBTAIN_ROOT" "9" "September 2017" "Kernel Hackers Manual 4\&.12\&" "The Linux VFS"
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.SH "NAME"
d_obtain_root \- find or allocate a dentry for a given inode
.SH "SYNOPSIS"
.HP \w'struct\ dentry\ *\ d_obtain_root('u
.BI "struct dentry * d_obtain_root(struct\ inode\ *\ " "inode" ");"
.SH "ARGUMENTS"
.PP
\fIstruct inode * inode\fR
.RS 4
inode to allocate the dentry for
.RE
.SH "DESCRIPTION"
.PP
Obtain an IS_ROOT dentry for the root of a filesystem\&.
.PP
We must ensure that directory inodes only ever have one dentry\&. If a dentry is found, that is returned instead of allocating a new one\&.
.PP
On successful return, the reference to the inode has been transferred to the dentry\&. In case of an error the reference on the inode is released\&. A
\fBNULL\fR
or IS_ERR inode may be passed in and will be the error will be propagate to the return value, with a
\fBNULL\fR
\fIinode\fR
replaced by ERR_PTR(\-ESTALE)\&.
.SH "COPYRIGHT"
.br