'\" t
.\"     Title: vm_map_ram
.\"    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 "VM_MAP_RAM" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Memory Management in Linux"
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.SH "NAME"
vm_map_ram \- map pages linearly into kernel virtual address (vmalloc space)
.SH "SYNOPSIS"
.HP \w'void\ *\ vm_map_ram('u
.BI "void * vm_map_ram(struct\ page\ **\ " "pages" ", unsigned\ int\ " "count" ", int\ " "node" ", pgprot_t\ " "prot" ");"
.SH "ARGUMENTS"
.PP
\fIpages\fR
.RS 4
an array of pointers to the pages to be mapped
.RE
.PP
\fIcount\fR
.RS 4
number of pages
.RE
.PP
\fInode\fR
.RS 4
prefer to allocate data structures on this node
.RE
.PP
\fIprot\fR
.RS 4
memory protection to use\&. PAGE_KERNEL for regular RAM
.RE
.SH "DESCRIPTION"
.PP
If you use this function for less than VMAP_MAX_ALLOC pages, it could be faster than vmap so it\*(Aqs good\&. But if you mix long\-life and short\-life objects with
\fBvm_map_ram\fR, it could consume lots of address space through fragmentation (especially on a 32bit machine)\&. You could see failures in the end\&. Please use this function for short\-lived objects\&.
.SH "RETURN"
.PP
a pointer to the address that has been mapped, or
\fBNULL\fR
on failure
.SH "COPYRIGHT"
.br