'\" t
.\"     Title: page_cache_async_readahead
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: July 2017
.\"    Manual: Memory Management in Linux
.\"    Source: Kernel Hackers Manual 4.11.6
.\"  Language: English
.\"
.TH "PAGE_CACHE_ASYNC_REA" "9" "July 2017" "Kernel Hackers Manual 4\&.11\&" "Memory Management in Linux"
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.SH "NAME"
page_cache_async_readahead \- file readahead for marked pages
.SH "SYNOPSIS"
.HP \w'void\ page_cache_async_readahead('u
.BI "void page_cache_async_readahead(struct\ address_space\ *\ " "mapping" ", struct\ file_ra_state\ *\ " "ra" ", struct\ file\ *\ " "filp" ", struct\ page\ *\ " "page" ", pgoff_t\ " "offset" ", unsigned\ long\ " "req_size" ");"
.SH "ARGUMENTS"
.PP
\fIstruct address_space * mapping\fR
.RS 4
address_space which holds the pagecache and I/O vectors
.RE
.PP
\fIstruct file_ra_state * ra\fR
.RS 4
file_ra_state which holds the readahead state
.RE
.PP
\fIstruct file * filp\fR
.RS 4
passed on to \->\fBreadpage\fR
and \->\fBreadpages\fR
.RE
.PP
\fIstruct page * page\fR
.RS 4
the page at
\fIoffset\fR
which has the PG_readahead flag set
.RE
.PP
\fIpgoff_t offset\fR
.RS 4
start offset into
\fImapping\fR, in pagecache page\-sized units
.RE
.PP
\fIunsigned long req_size\fR
.RS 4
hint: total size of the read which the caller is performing in pagecache pages
.RE
.SH "DESCRIPTION"
.PP
\fBpage_cache_async_readahead\fR
should be called when a page is used which has the PG_readahead flag; this is a marker to suggest that the application has used up enough of the readahead window that we should start pulling in more pages\&.
.SH "COPYRIGHT"
.br