'\" t
.\"     Title: dma_pool_create
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Memory Management in Linux
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "DMA_POOL_CREATE" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Memory Management in Linux"
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.SH "NAME"
dma_pool_create \- Creates a pool of consistent memory blocks, for dma\&.
.SH "SYNOPSIS"
.HP \w'struct\ dma_pool\ *\ dma_pool_create('u
.BI "struct dma_pool * dma_pool_create(const\ char\ *\ " "name" ", struct\ device\ *\ " "dev" ", size_t\ " "size" ", size_t\ " "align" ", size_t\ " "boundary" ");"
.SH "ARGUMENTS"
.PP
\fIname\fR
.RS 4
name of pool, for diagnostics
.RE
.PP
\fIdev\fR
.RS 4
device that will be doing the DMA
.RE
.PP
\fIsize\fR
.RS 4
size of the blocks in this pool\&.
.RE
.PP
\fIalign\fR
.RS 4
alignment requirement for blocks; must be a power of two
.RE
.PP
\fIboundary\fR
.RS 4
returned blocks won\*(Aqt cross this power of two boundary
.RE
.SH "CONTEXT"
.PP
!\fBin_interrupt\fR
.SH "DESCRIPTION"
.PP
Returns a dma allocation pool with the requested characteristics, or null if one can\*(Aqt be created\&. Given one of these pools,
\fBdma_pool_alloc\fR
may be used to allocate memory\&. Such memory will all have
\(lqconsistent\(rq
DMA mappings, accessible by the device and its driver without using cache flushing primitives\&. The actual size of blocks allocated may be larger than requested because of alignment\&.
.PP
If
\fIboundary\fR
is nonzero, objects returned from
\fBdma_pool_alloc\fR
won\*(Aqt cross that size boundary\&. This is useful for devices which have addressing restrictions on individual DMA transfers, such as not crossing boundaries of 4KBytes\&.
.SH "COPYRIGHT"
.br