NetBSD/sys/kern/subr_kmem.c

170 lines
4.0 KiB
C

/* $NetBSD: subr_kmem.c,v 1.2 2006/06/25 08:10:04 yamt Exp $ */
/*-
* Copyright (c)2006 YAMAMOTO Takashi,
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* allocator of kernel wired memory.
*
* TODO:
* - worth to have "intrsafe" version? maybe..
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: subr_kmem.c,v 1.2 2006/06/25 08:10:04 yamt Exp $");
#include <sys/param.h>
#include <sys/kmem.h>
#include <sys/vmem.h>
#include <lib/libkern/libkern.h>
#define KMEM_QUANTUM_SIZE sizeof(void *) /* XXX */
static vmem_t *kmem_arena;
static vmem_addr_t kmem_backend_alloc(vmem_t *, vmem_size_t, vmem_size_t *,
vm_flag_t);
static void kmem_backend_free(vmem_t *, vmem_addr_t, vmem_size_t);
static inline vm_flag_t
kmf_to_vmf(km_flag_t kmflags)
{
vm_flag_t vmflags;
KASSERT((kmflags & (KM_SLEEP|KM_NOSLEEP)) != 0);
KASSERT((~kmflags & (KM_SLEEP|KM_NOSLEEP)) != 0);
vmflags = 0;
if ((kmflags & KM_SLEEP) != 0) {
vmflags |= VM_SLEEP;
}
if ((kmflags & KM_NOSLEEP) != 0) {
vmflags |= VM_NOSLEEP;
}
return vmflags;
}
/* ---- kmem API */
/*
* kmem_alloc: allocate wired memory.
*
* => must not be called from interrupt context.
*/
void *
kmem_alloc(size_t size, km_flag_t kmflags)
{
return (void *)vmem_alloc(kmem_arena, size,
kmf_to_vmf(kmflags) | VM_INSTANTFIT);
}
/*
* kmem_zalloc: allocate wired memory.
*
* => must not be called from interrupt context.
*/
void *
kmem_zalloc(size_t size, km_flag_t kmflags)
{
void *p;
p = kmem_alloc(size, kmflags);
if (p != NULL) {
memset(p, 0, size);
}
return p;
}
/*
* kmem_free: free wired memory allocated by kmem_alloc.
*
* => must not be called from interrupt context.
*/
void
kmem_free(void *p, size_t size)
{
vmem_free(kmem_arena, (vmem_addr_t)p, size);
}
void
kmem_init(void)
{
kmem_arena = vmem_create("kmem", 0, 0, KMEM_QUANTUM_SIZE,
kmem_backend_alloc, kmem_backend_free, NULL, 0, VM_SLEEP);
}
size_t
kmem_roundup_size(size_t size)
{
return vmem_roundup_size(kmem_arena, size);
}
/* ---- uvm glue */
#include <uvm/uvm_extern.h>
static vmem_addr_t
kmem_backend_alloc(vmem_t *dummy, vmem_size_t size, vmem_size_t *resultsize,
vm_flag_t vmflags)
{
uvm_flag_t uflags;
KASSERT(dummy == NULL);
KASSERT(size != 0);
KASSERT((vmflags & (VM_SLEEP|VM_NOSLEEP)) != 0);
KASSERT((~vmflags & (VM_SLEEP|VM_NOSLEEP)) != 0);
if ((vmflags & VM_NOSLEEP) != 0) {
uflags = UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT;
} else {
uflags = UVM_KMF_WAITVA;
}
*resultsize = size = round_page(size);
return (vmem_addr_t)uvm_km_alloc(kernel_map, size, 0,
uflags | UVM_KMF_WIRED | UVM_KMF_CANFAIL);
}
static void
kmem_backend_free(vmem_t *dummy, vmem_addr_t addr, vmem_size_t size)
{
KASSERT(dummy == NULL);
KASSERT(addr != 0);
KASSERT(size != 0);
KASSERT(size == round_page(size));
uvm_km_free(kernel_map, (vaddr_t)addr, size, UVM_KMF_WIRED);
}