'\" t
.\"     Title: rpc_malloc
.\"    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 "RPC_MALLOC" "9" "July 2017" "Kernel Hackers Manual 4\&.12\&" "Linux Networking"
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.SH "NAME"
rpc_malloc \- allocate RPC buffer resources
.SH "SYNOPSIS"
.HP \w'int\ rpc_malloc('u
.BI "int rpc_malloc(struct\ rpc_task\ *\ " "task" ");"
.SH "ARGUMENTS"
.PP
\fIstruct rpc_task * task\fR
.RS 4
RPC task
.RE
.SH "DESCRIPTION"
.PP
A single memory region is allocated, which is split between the RPC call and RPC reply that this task is being used for\&. When this RPC is retired, the memory is released by calling rpc_free\&.
.PP
To prevent rpciod from hanging, this allocator never sleeps, returning \-ENOMEM and suppressing warning if the request cannot be serviced immediately\&. The caller can arrange to sleep in a way that is safe for rpciod\&.
.PP
Most requests are \*(Aqsmall\*(Aq (under 2KiB) and can be serviced from a mempool, ensuring that NFS reads and writes can always proceed, and that there is good locality of reference for these buffers\&.
.PP
In order to avoid memory starvation triggering more writebacks of NFS requests, we avoid using GFP_KERNEL\&.
.SH "COPYRIGHT"
.br