FreeBSD-5.3/sys/i386/i386/mem.c
/*-
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1982, 1986, 1990 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, and code derived from software contributed to
* Berkeley by William Jolitz.
*
* 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.
* 4. 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.
*
* from: Utah $Hdr: mem.c 1.13 89/10/08$
* from: @(#)mem.c 7.2 (Berkeley) 5/9/91
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/i386/i386/mem.c,v 1.116 2004/08/04 18:30:31 markm Exp $");
/*
* Memory special file
*/
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/ioccom.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/memrange.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <machine/specialreg.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>
#include <machine/memdev.h>
/*
* Used in /dev/mem drivers and elsewhere
*/
MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
/* ARGSUSED */
int
memrw(struct cdev *dev, struct uio *uio, int flags)
{
int o;
u_int c = 0, v;
struct iovec *iov;
int error = 0;
vm_offset_t addr, eaddr;
GIANT_REQUIRED;
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("memrw");
continue;
}
if (minor(dev) == CDEV_MINOR_MEM) {
v = uio->uio_offset;
v &= ~PAGE_MASK;
pmap_kenter((vm_offset_t)ptvmmap, v);
o = (int)uio->uio_offset & PAGE_MASK;
c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK));
c = min(c, (u_int)(PAGE_SIZE - o));
c = min(c, (u_int)iov->iov_len);
error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
pmap_qremove((vm_offset_t)ptvmmap, 1);
continue;
}
else if (minor(dev) == CDEV_MINOR_KMEM) {
c = iov->iov_len;
/*
* Make sure that all of the pages are currently
* resident so that we don't create any zero-fill
* pages.
*/
addr = trunc_page(uio->uio_offset);
eaddr = round_page(uio->uio_offset + c);
if (addr < (vm_offset_t)VADDR(PTDPTDI, 0))
return (EFAULT);
for (; addr < eaddr; addr += PAGE_SIZE)
if (pmap_extract(kernel_pmap, addr) == 0)
return (EFAULT);
if (!kernacc((caddr_t)(int)uio->uio_offset, c,
uio->uio_rw == UIO_READ ?
VM_PROT_READ : VM_PROT_WRITE))
return (EFAULT);
error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
continue;
}
/* else panic! */
}
return (error);
}
/*
* allow user processes to MMAP some memory sections
* instead of going through read/write
*/
/* ARGSUSED */
int
memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr,
int prot __unused)
{
if (minor(dev) == CDEV_MINOR_MEM)
*paddr = offset;
else if (minor(dev) == CDEV_MINOR_KMEM)
*paddr = vtophys(offset);
/* else panic! */
return (0);
}
/*
* Operations for changing memory attributes.
*
* This is basically just an ioctl shim for mem_range_attr_get
* and mem_range_attr_set.
*/
/* ARGSUSED */
int
memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
struct thread *td)
{
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 = (struct mem_range_desc *)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);
}
void
dev_mem_md_init(void)
{
if (mem_range_softc.mr_op != NULL)
mem_range_softc.mr_op->init(&mem_range_softc);
}