'\" t
.\"     Title: lock_may_write
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: May 2018
.\"    Manual: The Linux VFS
.\"    Source: Kernel Hackers Manual 3.16.56
.\"  Language: English
.\"
.TH "LOCK_MAY_WRITE" "9" "May 2018" "Kernel Hackers Manual 3\&.16\&" "The Linux VFS"
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.SH "NAME"
lock_may_write \- checks that the region is free of locks
.SH "SYNOPSIS"
.HP \w'int\ lock_may_write('u
.BI "int lock_may_write(struct\ inode\ *\ " "inode" ", loff_t\ " "start" ", unsigned\ long\ " "len" ");"
.SH "ARGUMENTS"
.PP
\fIinode\fR
.RS 4
the inode that is being written
.RE
.PP
\fIstart\fR
.RS 4
the first byte to write
.RE
.PP
\fIlen\fR
.RS 4
the number of bytes to write
.RE
.SH "DESCRIPTION"
.PP
Emulates Windows locking requirements\&. Whole\-file mandatory locks (share modes) can prohibit a write and byte\-range POSIX locks can prohibit a write if they overlap\&.
.PP
N\&.B\&. this function is only ever called from knfsd and ownership of locks is never checked\&.
.SH "COPYRIGHT"
.br