NetBSD/share/man/man9/vmem_alloc.9

.\"	$NetBSD: vmem_alloc.9,v 1.3 2006/11/04 12:39:50 yamt Exp $
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.\" Copyright (c)2006 YAMAMOTO Takashi,
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.\" ------------------------------------------------------------
.Dd October 22, 2006
.Dt VMEM_ALLOC 9
.Os
.\" ------------------------------------------------------------
.Sh NAME
.Nm vmem_alloc
.Nd Allocate resource from arena
.\" ------------------------------------------------------------
.Sh SYNOPSIS
.In sys/vmem.h
.\" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.Ft vmem_addr_t
.Fn vmem_alloc \
"vmem_t *vm" "vmem_size_t size" "vm_flag_t flags"
.\" ------------------------------------------------------------
.Sh DESCRIPTION
.Fn vmem_alloc
allocates a resource from the arena.
.Pp
.Bl -tag -width flags
.It Fa vm
The arena which we allocate from.
.It Fa size
Specify the size of the allocation.
.It Fa flags
A bitwise OR of an allocation strategy and a sleep flag.
.Pp
The allocation strategy is one of:
.Bl -tag -width VM_INSTANTFIT
.It Dv VM_BESTFIT
Prefer space efficiency.
.It Dv VM_INSTANTFIT
Prefer performance.
.El
.Pp
The sleep flag should be one of:
.Bl -tag -width VM_NOSLEEP
.It Dv VM_SLEEP
Can sleep until enough resources are available.
.It Dv VM_NOSLEEP
Don't sleep.
Immediately return
.Dv VMEM_ADDR_NULL
if there are not enough resources available.
.El
.El
.\" ------------------------------------------------------------
.Sh RETURN VALUES
On success,
.Fn vmem_alloc
returns an allocated vmem_addr_t.
Otherwise, it returns
.Dv VMEM_ADDR_NULL .
.\" ------------------------------------------------------------
.Sh SEE ALSO
.Xr intro 9 ,
.Xr vmem 9