'\" t
.\"     Title: tag_pages_for_writeback
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: June 2017
.\"    Manual: Memory Management in Linux
.\"    Source: Kernel Hackers Manual 4.11.3
.\"  Language: English
.\"
.TH "TAG_PAGES_FOR_WRITEB" "9" "June 2017" "Kernel Hackers Manual 4\&.11\&" "Memory Management in Linux"
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.SH "NAME"
tag_pages_for_writeback \- tag pages to be written by write_cache_pages
.SH "SYNOPSIS"
.HP \w'void\ tag_pages_for_writeback('u
.BI "void tag_pages_for_writeback(struct\ address_space\ *\ " "mapping" ", pgoff_t\ " "start" ", pgoff_t\ " "end" ");"
.SH "ARGUMENTS"
.PP
\fIstruct address_space * mapping\fR
.RS 4
address space structure to write
.RE
.PP
\fIpgoff_t start\fR
.RS 4
starting page index
.RE
.PP
\fIpgoff_t end\fR
.RS 4
ending page index (inclusive)
.RE
.SH "DESCRIPTION"
.PP
This function scans the page range from
\fIstart\fR
to
\fIend\fR
(inclusive) and tags all pages that have DIRTY tag set with a special TOWRITE tag\&. The idea is that write_cache_pages (or whoever calls this function) will then use TOWRITE tag to identify pages eligible for writeback\&. This mechanism is used to avoid livelocking of writeback by a process steadily creating new dirty pages in the file (thus it is important for this function to be quick so that it can tag pages faster than a dirtying process can create them)\&.
.SH "COPYRIGHT"
.br