'\" t
.\"     Title: find_inode_nowait
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: The Linux VFS
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "FIND_INODE_NOWAIT" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "The Linux VFS"
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.SH "NAME"
find_inode_nowait \- find an inode in the inode cache
.SH "SYNOPSIS"
.HP \w'struct\ inode\ *\ find_inode_nowait('u
.BI "struct inode * find_inode_nowait(struct\ super_block\ *\ " "sb" ", unsigned\ long\ " "hashval" ", int\ (*" "match" ")\ (struct\ inode\ *,\ unsigned\ long,\ void\ *), void\ *\ " "data" ");"
.SH "ARGUMENTS"
.PP
\fIsb\fR
.RS 4
super block of file system to search
.RE
.PP
\fIhashval\fR
.RS 4
hash value (usually inode number) to search for
.RE
.PP
\fImatch\fR
.RS 4
callback used for comparisons between inodes
.RE
.PP
\fIdata\fR
.RS 4
opaque data pointer to pass to
\fImatch\fR
.RE
.SH "DESCRIPTION"
.PP
Search for the inode specified by
\fIhashval\fR
and
\fIdata\fR
in the inode cache, where the helper function
\fImatch\fR
will return 0 if the inode does not match, 1 if the inode does match, and \-1 if the search should be stopped\&. The
\fImatch\fR
function must be responsible for taking the i_lock spin_lock and checking i_state for an inode being freed or being initialized, and incrementing the reference count before returning 1\&. It also must not sleep, since it is called with the inode_hash_lock spinlock held\&.
.PP
This is a even more generalized version of
\fBilookup5\fR
when the function must never block \-\-\-
\fBfind_inode\fR
can block in
\fB__wait_on_freeing_inode\fR
\-\-\- or when the caller can not increment the reference count because the resulting
\fBiput\fR
might cause an inode eviction\&. The tradeoff is that the
\fImatch\fR
funtion must be very carefully implemented\&.
.SH "COPYRIGHT"
.br