freebsd-nq/sys/boot/ofw/libofw/ofw_disk.c
Toomas Soome 1ecc859193 dosfs support in libstand is broken since r298230
Apparently the libstand dosfs optimization is a bit too optimistic
and did introduce possible memory corruption.

This patch is backing out the bad part and since this results in
dosfs reading full blocks now, we can also remove extra offset argument
from dv_strategy callback.

The analysis of the issue and the backout patch is provided by Mikhail Kupchik.

PR:		214423
Submitted by:	Mikhail Kupchik
Reported by:	Mikhail Kupchik
Reviewed by:	bapt, allanjude
Approved by:	allanjude (mentor)
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D8644
2016-12-30 19:06:29 +00:00

169 lines
4.2 KiB
C

/*-
* Copyright (C) 2000 Benno Rice.
* 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 Benno Rice ``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 TOOLS GMBH 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Disk I/O routines using Open Firmware
*/
#include <sys/param.h>
#include <netinet/in.h>
#include <machine/stdarg.h>
#include <stand.h>
#include "bootstrap.h"
#include "libofw.h"
static int ofwd_init(void);
static int ofwd_strategy(void *devdata, int flag, daddr_t dblk,
size_t size, char *buf, size_t *rsize);
static int ofwd_open(struct open_file *f, ...);
static int ofwd_close(struct open_file *f);
static int ofwd_ioctl(struct open_file *f, u_long cmd, void *data);
static int ofwd_print(int verbose);
struct devsw ofwdisk = {
"block",
DEVT_DISK,
ofwd_init,
ofwd_strategy,
ofwd_open,
ofwd_close,
ofwd_ioctl,
ofwd_print
};
/*
* We're not guaranteed to be able to open a device more than once and there
* is no OFW standard method to determine whether a device is already opened.
* Opening a device multiple times simultaneously happens to work with most
* OFW block device drivers but triggers a trap with at least the driver for
* the on-board controllers of Sun Fire V100 and Ultra 1. Upper layers and MI
* code expect to be able to open a device more than once however. Given that
* different partitions of the same device might be opened at the same time as
* done by ZFS, we can't generally just keep track of the opened devices and
* reuse the instance handle when asked to open an already opened device. So
* the best we can do is to cache the lastly used device path and close and
* open devices in ofwd_strategy() as needed.
*/
static struct ofw_devdesc *kdp;
static int
ofwd_init(void)
{
return (0);
}
static int
ofwd_strategy(void *devdata, int flag __unused, daddr_t dblk, size_t size,
char *buf, size_t *rsize)
{
struct ofw_devdesc *dp = (struct ofw_devdesc *)devdata;
daddr_t pos;
int n;
if (dp != kdp) {
if (kdp != NULL) {
#if !defined(__powerpc__)
OF_close(kdp->d_handle);
#endif
kdp = NULL;
}
if ((dp->d_handle = OF_open(dp->d_path)) == -1)
return (ENOENT);
kdp = dp;
}
pos = dblk * 512;
do {
if (OF_seek(dp->d_handle, pos) < 0)
return (EIO);
n = OF_read(dp->d_handle, buf, size);
if (n < 0 && n != -2)
return (EIO);
} while (n == -2);
*rsize = size;
return (0);
}
static int
ofwd_open(struct open_file *f, ...)
{
struct ofw_devdesc *dp;
va_list vl;
va_start(vl, f);
dp = va_arg(vl, struct ofw_devdesc *);
va_end(vl);
if (dp != kdp) {
if (kdp != NULL) {
OF_close(kdp->d_handle);
kdp = NULL;
}
if ((dp->d_handle = OF_open(dp->d_path)) == -1) {
printf("%s: Could not open %s\n", __func__,
dp->d_path);
return (ENOENT);
}
kdp = dp;
}
return (0);
}
static int
ofwd_close(struct open_file *f)
{
struct ofw_devdesc *dev = f->f_devdata;
if (dev == kdp) {
#if !defined(__powerpc__)
OF_close(dev->d_handle);
#endif
kdp = NULL;
}
return (0);
}
static int
ofwd_ioctl(struct open_file *f __unused, u_long cmd __unused,
void *data __unused)
{
return (EINVAL);
}
static int
ofwd_print(int verbose __unused)
{
return (0);
}