'\" t
.\"     Title: enum positive_aop_returns
.\"    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: The Linux VFS
.\"    Source: Kernel Hackers Manual 4.11.6
.\"  Language: English
.\"
.TH "ENUM POSITIVE_AOP_RE" "9" "July 2017" "Kernel Hackers Manual 4\&.11\&" "The Linux VFS"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
enum_positive_aop_returns \- aop return codes with specific semantics
.SH "SYNOPSIS"
.sp
.nf
enum positive_aop_returns {
  AOP_WRITEPAGE_ACTIVATE,
  AOP_TRUNCATED_PAGE
};  
.fi
.SH "CONSTANTS"
.PP
AOP_WRITEPAGE_ACTIVATE
.RS 4
Informs the caller that page writeback has completed, that the page is still locked, and should be considered active\&. The VM uses this hint to return the page to the active list \-\- it won\*(Aqt be a candidate for writeback again in the near future\&. Other callers must be careful to unlock the page if they get this return\&. Returned by
\fBwritepage\fR;
.RE
.PP
AOP_TRUNCATED_PAGE
.RS 4
The AOP method that was handed a locked page has unlocked it and the page might have been truncated\&. The caller should back up to acquiring a new page and trying again\&. The aop will be taking reasonable precautions not to livelock\&. If the caller held a page reference, it should drop it before retrying\&. Returned by
\fBreadpage\fR\&.
.RE
.SH "DESCRIPTION"
.PP
address_space_operation functions return these large constants to indicate special semantics to the caller\&. These are much larger than the bytes in a page to allow for functions that return the number of bytes operated on in a given page\&.
.SH "COPYRIGHT"
.br