Source to i386/i386/mem.c
/*-
* 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, 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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 $Hdr: mem.c 1.13 89/10/08$
* @(#)mem.c 8.1 (Berkeley) 6/11/93
*/
/*
* Memory special file
*/
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/buf.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <machine/cpu.h>
#include <vm/vm_param.h>
#include <vm/lock.h>
#include <vm/vm_prot.h>
#include <vm/pmap.h>
extern char *vmmap; /* poor name! */
/*ARGSUSED*/
mmrw(dev, uio, flags)
dev_t dev;
struct uio *uio;
int flags;
{
register int o;
register u_int c, v;
register struct iovec *iov;
int error = 0;
caddr_t zbuf = NULL;
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(kernel_pmap, vmmap, v,
uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE,
TRUE);
o = (int)uio->uio_offset & PGOFSET;
c = (u_int)(NBPG - ((int)iov->iov_base & PGOFSET));
c = min(c, (u_int)(NBPG - o));
c = min(c, (u_int)iov->iov_len);
error = uiomove((caddr_t)&vmmap[o], (int)c, uio);
pmap_remove(kernel_pmap, vmmap, &vmmap[NBPG]);
continue;
/* minor device 1 is kernel memory */
case 1:
c = iov->iov_len;
if (!kernacc((caddr_t)uio->uio_offset, c,
uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
return(EFAULT);
error = uiomove((caddr_t)uio->uio_offset, (int)c, uio);
continue;
/* minor device 2 is EOF/RATHOLE */
case 2:
if (uio->uio_rw == UIO_READ)
return (0);
c = iov->iov_len;
break;
/* 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 (zbuf == NULL) {
zbuf = (caddr_t)
malloc(CLBYTES, M_TEMP, M_WAITOK);
bzero(zbuf, CLBYTES);
}
c = min(iov->iov_len, CLBYTES);
error = uiomove(zbuf, (int)c, uio);
continue;
#ifdef notyet
/* 386 I/O address space (/dev/ioport[bwl]) is a read/write access to seperate
i/o device address bus, different than memory bus. Semantics here are
very different than ordinary read/write, as if iov_len is a multiple
an implied string move from a single port will be done. Note that lseek
must be used to set the port number reliably. */
case 14:
if (iov->iov_len == 1) {
u_char tmp;
tmp = inb(uio->uio_offset);
error = uiomove (&tmp, iov->iov_len, uio);
} else {
if (!useracc((caddr_t)iov->iov_base,
iov->iov_len, uio->uio_rw))
return (EFAULT);
insb(uio->uio_offset, iov->iov_base,
iov->iov_len);
}
break;
case 15:
if (iov->iov_len == sizeof (short)) {
u_short tmp;
tmp = inw(uio->uio_offset);
error = uiomove (&tmp, iov->iov_len, uio);
} else {
if (!useracc((caddr_t)iov->iov_base,
iov->iov_len, uio->uio_rw))
return (EFAULT);
insw(uio->uio_offset, iov->iov_base,
iov->iov_len/ sizeof (short));
}
break;
case 16:
if (iov->iov_len == sizeof (long)) {
u_long tmp;
tmp = inl(uio->uio_offset);
error = uiomove (&tmp, iov->iov_len, uio);
} else {
if (!useracc((caddr_t)iov->iov_base,
iov->iov_len, uio->uio_rw))
return (EFAULT);
insl(uio->uio_offset, iov->iov_base,
iov->iov_len/ sizeof (long));
}
break;
#endif
default:
return (ENXIO);
}
if (error)
break;
iov->iov_base += c;
iov->iov_len -= c;
uio->uio_offset += c;
uio->uio_resid -= c;
}
if (zbuf)
free(zbuf, M_TEMP);
return (error);
}