freebsd-dev/usr.sbin/memcontrol/memcontrol.c
dwmalone 933818aa30 Make the MTRR code a bit more defensive - this should help people
trying to run X on some Athlon systems where the BIOS does odd things
(mines an ASUS A7A266, but it seems to also help on other systems).

Here's a description of the problem and my fix:

        The problem with the old MTRR code is that it only expects
        to find documented values in the bytes of MTRR registers.
        To convert the MTRR byte into a FreeBSD "Memory Range Type"
        (mrt) it uses the byte value and looks it up in an array.
        If the value is not in range then the mrt value ends up
        containing random junk.

        This isn't an immediate problem. The mrt value is only used
        later when rewriting the MTRR registers. When we finally
        go to write a value back again, the function i686_mtrrtype()
        searches for the junk value and returns -1 when it fails
        to find it. This is converted to a byte (0xff) and written
        back to the register, causing a GPF as 0xff is an illegal
        value for a MTRR byte.

	To work around this problem I've added a new mrt flag
	MDF_UNKNOWN.  We set this when we read a MTRR byte which
	we do not understand.  If we try to convert a MDF_UNKNOWN
	back into a MTRR value, then the new function, i686_mrt2mtrr,
	just returns the old value of the MTRR byte. This leaves
	the memory range type unchanged.

I have seen one side effect of the fix, which is that ACPI calls
after X has been run seem to hang my machine. As running X would
previously panic the machine, this is still an improvement ;-)

I'd like to MFC this before the 4.6 code freeze - please let me
know if it causes any problems.

PR:		28418, 25958
Tested by:	jkh, Christopher Masto <chris@netmonger.net>
MFC after:	2 weeks
2002-04-14 20:19:13 +00:00

343 lines
8.8 KiB
C

/*-
* Copyright (c) 1999 Michael Smith <msmith@freebsd.org>
* 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.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/memrange.h>
#include <err.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
struct
{
char *name;
int val;
int kind;
#define MDF_SETTABLE (1<<0)
} attrnames[] = {
{"uncacheable", MDF_UNCACHEABLE, MDF_SETTABLE},
{"write-combine", MDF_WRITECOMBINE, MDF_SETTABLE},
{"write-through", MDF_WRITETHROUGH, MDF_SETTABLE},
{"write-back", MDF_WRITEBACK, MDF_SETTABLE},
{"write-protect", MDF_WRITEPROTECT, MDF_SETTABLE},
{"unknown", MDF_UNKNOWN, 0},
{"fixed-base", MDF_FIXBASE, 0},
{"fixed-length", MDF_FIXLEN, 0},
{"set-by-firmware", MDF_FIRMWARE, 0},
{"active", MDF_ACTIVE, MDF_SETTABLE},
{"bogus", MDF_BOGUS, 0},
{NULL, 0, 0}
};
static void listfunc(int memfd, int argc, char *argv[]);
static void setfunc(int memfd, int argc, char *argv[]);
static void clearfunc(int memfd, int argc, char *argv[]);
static void helpfunc(int memfd, int argc, char *argv[]);
static void help(char *what);
struct
{
char *cmd;
char *desc;
void (*func)(int memfd, int argc, char *argv[]);
} functions[] = {
{"list",
"List current memory range attributes\n"
" list [-a]\n"
" -a list all range slots, even those that are inactive",
listfunc},
{"set",
"Set memory range attributes\n"
" set -b <base> -l <length> -o <owner> <attribute>\n"
" <base> memory range base address\n"
" <length> length of memory range in bytes, power of 2\n"
" <owner> text identifier for this setting (7 char max)\n"
" <attribute> attribute(s) to be applied to this range:\n"
" uncacheable\n"
" write-combine\n"
" write-through\n"
" write-back\n"
" write-protect",
setfunc},
{"clear",
"Clear memory range attributes\n"
" clear -o <owner>\n"
" <owner> all ranges with this owner will be cleared\n"
" clear -b <base> -l <length>\n"
" <base> memory range base address\n"
" <length> length of memory range in bytes, power of 2\n"
" Base and length must exactly match an existing range",
clearfunc},
{NULL, NULL, helpfunc}
};
int
main(int argc, char *argv[])
{
int i, memfd;
if (argc < 2) {
help(NULL);
} else {
if ((memfd = open(_PATH_MEM, O_RDONLY)) == -1)
err(1, "can't open %s", _PATH_MEM);
for (i = 0; functions[i].cmd != NULL; i++)
if (!strcmp(argv[1], functions[i].cmd))
break;
functions[i].func(memfd, argc - 1, argv + 1);
close(memfd);
}
return(0);
}
static struct mem_range_desc *
mrgetall(int memfd, int *nmr)
{
struct mem_range_desc *mrd;
struct mem_range_op mro;
mro.mo_arg[0] = 0;
if (ioctl(memfd, MEMRANGE_GET, &mro))
err(1, "can't size range descriptor array");
*nmr = mro.mo_arg[0];
mrd = malloc(*nmr * sizeof(struct mem_range_desc));
if (mrd == NULL)
errx(1, "can't allocate %d bytes for %d range descriptors",
*nmr * sizeof(struct mem_range_desc), *nmr);
mro.mo_arg[0] = *nmr;
mro.mo_desc = mrd;
if (ioctl(memfd, MEMRANGE_GET, &mro))
err(1, "can't fetch range descriptor array");
return(mrd);
}
static void
listfunc(int memfd, int argc, char *argv[])
{
struct mem_range_desc *mrd;
int nd, i, j;
int ch;
int showall = 0;
char *owner;
owner = NULL;
while ((ch = getopt(argc, argv, "ao:")) != -1)
switch(ch) {
case 'a':
showall = 1;
break;
case 'o':
owner = strdup(optarg);
break;
case '?':
default:
help("list");
}
mrd = mrgetall(memfd, &nd);
for (i = 0; i < nd; i++) {
if (!showall && !(mrd[i].mr_flags & MDF_ACTIVE))
continue;
if (owner && strcmp(mrd[i].mr_owner, owner))
continue;
printf("%qx/%qx %.8s ", mrd[i].mr_base, mrd[i].mr_len,
mrd[i].mr_owner[0] ? mrd[i].mr_owner : "-");
for (j = 0; attrnames[j].name != NULL; j++)
if (mrd[i].mr_flags & attrnames[j].val)
printf("%s ", attrnames[j].name);
printf("\n");
}
free(mrd);
if (owner)
free(owner);
}
static void
setfunc(int memfd, int argc, char *argv[])
{
struct mem_range_desc mrd;
struct mem_range_op mro;
int i;
int ch;
char *ep;
mrd.mr_base = 0;
mrd.mr_len = 0;
mrd.mr_flags = 0;
strcpy(mrd.mr_owner, "user");
while ((ch = getopt(argc, argv, "b:l:o:")) != -1)
switch(ch) {
case 'b':
mrd.mr_base = strtouq(optarg, &ep, 0);
if ((ep == optarg) || (*ep != 0))
help("set");
break;
case 'l':
mrd.mr_len = strtouq(optarg, &ep, 0);
if ((ep == optarg) || (*ep != 0))
help("set");
break;
case 'o':
if ((*optarg == 0) || (strlen(optarg) > 7))
help("set");
strcpy(mrd.mr_owner, optarg);
break;
case '?':
default:
help("set");
}
if (mrd.mr_len == 0)
help("set");
argc -= optind;
argv += optind;
while(argc--) {
for (i = 0; attrnames[i].name != NULL; i++) {
if (!strcmp(attrnames[i].name, argv[0])) {
if (!attrnames[i].kind & MDF_SETTABLE)
help("flags");
mrd.mr_flags |= attrnames[i].val;
break;
}
}
if (attrnames[i].name == NULL)
help("flags");
argv++;
}
mro.mo_desc = &mrd;
mro.mo_arg[0] = 0;
if (ioctl(memfd, MEMRANGE_SET, &mro))
err(1, "can't set range");
}
static void
clearfunc(int memfd, int argc, char *argv[])
{
struct mem_range_desc mrd, *mrdp;
struct mem_range_op mro;
int i, nd;
int ch;
char *ep, *owner;
mrd.mr_base = 0;
mrd.mr_len = 0;
owner = NULL;
while ((ch = getopt(argc, argv, "b:l:o:")) != -1)
switch(ch) {
case 'b':
mrd.mr_base = strtouq(optarg, &ep, 0);
if ((ep == optarg) || (*ep != 0))
help("clear");
break;
case 'l':
mrd.mr_len = strtouq(optarg, &ep, 0);
if ((ep == optarg) || (*ep != 0))
help("clear");
break;
case 'o':
if ((*optarg == 0) || (strlen(optarg) > 7))
help("clear");
owner = strdup(optarg);
break;
case '?':
default:
help("clear");
}
if (owner != NULL) {
/* clear-by-owner */
if ((mrd.mr_base != 0) || (mrd.mr_len != 0))
help("clear");
mrdp = mrgetall(memfd, &nd);
mro.mo_arg[0] = MEMRANGE_SET_REMOVE;
for (i = 0; i < nd; i++) {
if (!strcmp(owner, mrdp[i].mr_owner) &&
(mrdp[i].mr_flags & MDF_ACTIVE) &&
!(mrdp[i].mr_flags & MDF_FIXACTIVE)) {
mro.mo_desc = mrdp + i;
if (ioctl(memfd, MEMRANGE_SET, &mro))
warn("couldn't clear range owned by '%s'", owner);
}
}
} else if (mrd.mr_len != 0) {
/* clear-by-base/len */
mro.mo_arg[0] = MEMRANGE_SET_REMOVE;
mro.mo_desc = &mrd;
if (ioctl(memfd, MEMRANGE_SET, &mro))
err(1, "couldn't clear range");
} else {
help("clear");
}
}
static void
helpfunc(int memfd, int argc, char *argv[])
{
help(argv[1]);
}
static void
help(char *what)
{
int i;
if (what != NULL) {
/* find a function that matches */
for (i = 0; functions[i].cmd != NULL; i++)
if (!strcmp(what, functions[i].cmd)) {
fprintf(stderr, "%s\n", functions[i].desc);
return;
}
fprintf(stderr, "Unknown command '%s'\n", what);
}
/* print general help */
fprintf(stderr, "Valid commands are :\n");
for (i = 0; functions[i].cmd != NULL; i++)
fprintf(stderr, " %s\n", functions[i].cmd);
fprintf(stderr, "Use help <command> for command-specific help\n");
}