'\" t
.\"     Title: skb_zerocopy
.\"    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: Linux Networking
.\"    Source: Kernel Hackers Manual 4.12.2
.\"  Language: English
.\"
.TH "SKB_ZEROCOPY" "9" "July 2017" "Kernel Hackers Manual 4\&.12\&" "Linux Networking"
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.SH "NAME"
skb_zerocopy \- Zero copy skb to skb
.SH "SYNOPSIS"
.HP \w'int\ skb_zerocopy('u
.BI "int skb_zerocopy(struct\ sk_buff\ *\ " "to" ", struct\ sk_buff\ *\ " "from" ", int\ " "len" ", int\ " "hlen" ");"
.SH "ARGUMENTS"
.PP
\fIstruct sk_buff * to\fR
.RS 4
destination buffer
.RE
.PP
\fIstruct sk_buff * from\fR
.RS 4
source buffer
.RE
.PP
\fIint len\fR
.RS 4
number of bytes to copy from source buffer
.RE
.PP
\fIint hlen\fR
.RS 4
size of linear headroom in destination buffer
.RE
.SH "DESCRIPTION"
.PP
Copies up to `len` bytes from `from` to `to` by creating references to the frags in the source buffer\&.
.PP
The `hlen` as calculated by
\fBskb_zerocopy_headlen\fR
specifies the headroom in the `to` buffer\&.
.PP
Return value: 0: everything is OK \-ENOMEM: couldn\*(Aqt orphan frags of
\fIfrom\fR
due to lack of memory \-EFAULT:
\fBskb_copy_bits\fR
found some problem with skb geometry
.SH "COPYRIGHT"
.br