'\" t
.\"     Title: unmap_mapping_range
.\"    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 "UNMAP_MAPPING_RANGE" "9" "June 2017" "Kernel Hackers Manual 4\&.11\&" "Memory Management in Linux"
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.SH "NAME"
unmap_mapping_range \- unmap the portion of all mmaps in the specified address_space corresponding to the specified page range in the underlying file\&.
.SH "SYNOPSIS"
.HP \w'void\ unmap_mapping_range('u
.BI "void unmap_mapping_range(struct\ address_space\ *\ " "mapping" ", loff_t\ const\ " "holebegin" ", loff_t\ const\ " "holelen" ", int\ " "even_cows" ");"
.SH "ARGUMENTS"
.PP
\fIstruct address_space * mapping\fR
.RS 4
the address space containing mmaps to be unmapped\&.
.RE
.PP
\fIloff_t const holebegin\fR
.RS 4
byte in first page to unmap, relative to the start of the underlying file\&. This will be rounded down to a PAGE_SIZE boundary\&. Note that this is different from
\fBtruncate_pagecache\fR, which must keep the partial page\&. In contrast, we must get rid of partial pages\&.
.RE
.PP
\fIloff_t const holelen\fR
.RS 4
size of prospective hole in bytes\&. This will be rounded up to a PAGE_SIZE boundary\&. A holelen of zero truncates to the end of the file\&.
.RE
.PP
\fIint even_cows\fR
.RS 4
1 when truncating a file, unmap even private COWed pages; but 0 when invalidating pagecache, don\*(Aqt throw away private data\&.
.RE
.SH "COPYRIGHT"
.br