/* $NetBSD: mem.c,v 1.31 1996/05/03 19:42:19 christos Exp $ */
/* $OpenBSD: mem.c,v 1.32 2006/12/29 13:04:37 pedro Exp $ */
/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1982, 1986, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)mem.c 8.3 (Berkeley) 1/12/94
*/
/*
* Memory special file
*/
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/ioccom.h>
#include <sys/malloc.h>
#include <sys/memrange.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <machine/cpu.h>
#include <machine/conf.h>
#include <uvm/uvm_extern.h>
#include "mtrr.h"
extern char *vmmap; /* poor name! */
caddr_t zeropage;
/* open counter for aperture */
#ifdef APERTURE
static int ap_open_count = 0;
extern int allowaperture;
#define VGA_START 0xA0000
#define BIOS_END 0xFFFFF
#endif
#if NMTRR > 0
struct mem_range_softc mem_range_softc;
static int mem_ioctl(dev_t, u_long, caddr_t, int, struct proc *);
#endif
/*ARGSUSED*/
int
mmopen(dev_t dev, int flag, int mode, struct proc *p)
{
switch (minor(dev)) {
case 0:
case 1:
case 2:
case 12:
break;
#ifdef APERTURE
case 4:
if (suser(p, 0) != 0 || !allowaperture)
return (EPERM);
/* authorize only one simultaneous open() */
if (ap_open_count > 0)
return(EPERM);
ap_open_count++;
break;
#endif
default:
return (ENXIO);
}
return (0);
}
/*ARGSUSED*/
int
mmclose(dev_t dev, int flag, int mode, struct proc *p)
{
#ifdef APERTURE
if (minor(dev) == 4)
ap_open_count--;
#endif
return (0);
}
/*ARGSUSED*/
int
mmrw(dev_t dev, struct uio *uio, int flags)
{
vaddr_t o, v;
int c;
struct iovec *iov;
int error = 0;
static int physlock;
if (minor(dev) == 0) {
/* lock against other uses of shared vmmap */
while (physlock > 0) {
physlock++;
error = tsleep((caddr_t)&physlock, PZERO | PCATCH,
"mmrw", 0);
if (error)
return (error);
}
physlock = 1;
}
while (uio->uio_resid > 0 && error == 0) {
iov = uio->uio_iov;
if (iov->iov_len == 0) {
uio->uio_iov++;
uio->uio_iovcnt--;
if (uio->uio_iovcnt < 0)
panic("mmrw");
continue;
}
switch (minor(dev)) {
/* minor device 0 is physical memory */
case 0:
v = uio->uio_offset;
pmap_enter(pmap_kernel(), (vaddr_t)vmmap,
trunc_page(v), uio->uio_rw == UIO_READ ?
VM_PROT_READ : VM_PROT_WRITE, PMAP_WIRED);
pmap_update(pmap_kernel());
o = uio->uio_offset & PGOFSET;
c = min(uio->uio_resid, (int)(NBPG - o));
error = uiomove((caddr_t)vmmap + o, c, uio);
pmap_remove(pmap_kernel(), (vaddr_t)vmmap,
(vaddr_t)vmmap + NBPG);
pmap_update(pmap_kernel());
continue;
/* minor device 1 is kernel memory */
case 1:
v = uio->uio_offset;
c = min(iov->iov_len, MAXPHYS);
if (!uvm_kernacc((caddr_t)v, c,
uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
return (EFAULT);
error = uiomove((caddr_t)v, c, uio);
continue;
/* minor device 2 is EOF/RATHOLE */
case 2:
if (uio->uio_rw == UIO_WRITE)
uio->uio_resid = 0;
return (0);
/* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
case 12:
if (uio->uio_rw == UIO_WRITE) {
c = iov->iov_len;
break;
}
if (zeropage == NULL) {
zeropage = (caddr_t)
malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
bzero(zeropage, PAGE_SIZE);
}
c = min(iov->iov_len, PAGE_SIZE);
error = uiomove(zeropage, c, uio);
continue;
default:
return (ENXIO);
}
(char *)iov->iov_base += c;
iov->iov_len -= c;
uio->uio_offset += c;
uio->uio_resid -= c;
}
if (minor(dev) == 0) {
if (physlock > 1)
wakeup((caddr_t)&physlock);
physlock = 0;
}
return (error);
}
paddr_t
mmmmap(dev_t dev, off_t off, int prot)
{
struct proc *p = curproc; /* XXX */
switch (minor(dev)) {
/* minor device 0 is physical memory */
case 0:
if ((u_int)off > ctob(physmem) &&
suser(p, 0) != 0)
return -1;
return atop(off);
#ifdef APERTURE
/* minor device 4 is aperture driver */
case 4:
switch (allowaperture) {
case 1:
/* Allow mapping of the VGA framebuffer & BIOS only */
if ((off >= VGA_START && off <= BIOS_END) ||
(unsigned)off > (unsigned)ctob(physmem))
return atop(off);
else
return -1;
case 2:
/* Allow mapping of the whole 1st megabyte
for x86emu */
if (off <= BIOS_END ||
(unsigned)off > (unsigned)ctob(physmem))
return atop(off);
else
return -1;
default:
return -1;
}
#endif
default:
return -1;
}
}
int
mmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
{
#if NMTRR > 0
switch (minor(dev)) {
case 0:
case 4:
return mem_ioctl(dev, cmd, data, flags, p);
}
#endif
return (ENODEV);
}
#if NMTRR > 0
/*
* Operations for changing memory attributes.
*
* This is basically just an ioctl shim for mem_range_attr_get
* and mem_range_attr_set.
*/
static int
mem_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
{
int nd, error = 0;
struct mem_range_op *mo = (struct mem_range_op *)data;
struct mem_range_desc *md;
/* is this for us? */
if ((cmd != MEMRANGE_GET) &&
(cmd != MEMRANGE_SET))
return (ENOTTY);
/* any chance we can handle this? */
if (mem_range_softc.mr_op == NULL)
return (EOPNOTSUPP);
/* do we have any descriptors? */
if (mem_range_softc.mr_ndesc == 0)
return (ENXIO);
switch (cmd) {
case MEMRANGE_GET:
nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
if (nd > 0) {
md = (struct mem_range_desc *)
malloc(nd * sizeof(struct mem_range_desc),
M_MEMDESC, M_WAITOK);
error = mem_range_attr_get(md, &nd);
if (!error)
error = copyout(md, mo->mo_desc,
nd * sizeof(struct mem_range_desc));
free(md, M_MEMDESC);
} else {
nd = mem_range_softc.mr_ndesc;
}
mo->mo_arg[0] = nd;
break;
case MEMRANGE_SET:
md = malloc(sizeof(struct mem_range_desc), M_MEMDESC, M_WAITOK);
error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
/* clamp description string */
md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
if (error == 0)
error = mem_range_attr_set(md, &mo->mo_arg[0]);
free(md, M_MEMDESC);
break;
}
return (error);
}
/*
* Implementation-neutral, kernel-callable functions for manipulating
* memory range attributes.
*/
int
mem_range_attr_get(struct mem_range_desc *mrd, int *arg)
{
/* can we handle this? */
if (mem_range_softc.mr_op == NULL)
return (EOPNOTSUPP);
if (*arg == 0) {
*arg = mem_range_softc.mr_ndesc;
} else {
bcopy(mem_range_softc.mr_desc, mrd, (*arg) * sizeof(struct mem_range_desc));
}
return (0);
}
int
mem_range_attr_set(struct mem_range_desc *mrd, int *arg)
{
/* can we handle this? */
if (mem_range_softc.mr_op == NULL)
return (EOPNOTSUPP);
return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
}
#endif /* NMTRR > 0 */