'\" t
.\"     Title: fault_in_user_writeable
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Futex API reference
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "FAULT_IN_USER_WRITEA" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Futex API reference"
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.SH "NAME"
fault_in_user_writeable \- Fault in user address and verify RW access
.SH "SYNOPSIS"
.HP \w'int\ fault_in_user_writeable('u
.BI "int fault_in_user_writeable(u32\ __user\ *\ " "uaddr" ");"
.SH "ARGUMENTS"
.PP
\fIuaddr\fR
.RS 4
pointer to faulting user space address
.RE
.SH "DESCRIPTION"
.PP
Slow path to fixup the fault we just took in the atomic write access to
\fIuaddr\fR\&.
.PP
We have no generic implementation of a non\-destructive write to the user address\&. We know that we faulted in the atomic pagefault disabled section so we can as well avoid the #PF overhead by calling
\fBget_user_pages\fR
right away\&.
.SH "AUTHOR"
.PP
\fBRusty Russell\fR <\&rusty@rustcorp.com.au\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br