freebsd-dev/sys/boot/ofw/libofw/ofw_disk.c
Marius Strobl f6dd28dc27 The workaround added in r151650 for handling firmwares that don't allow
a single device to be opened multiple times concurrently unfortunately
isn't sufficient with ZFS. This is due to the fact, that ZFS may open
different partitions of a single device simultaneously. So the best we
can do in this case is to cache the lastly used device path and close
and open devices in ofwd_strategy() as needed.

PR:		165025
Submitted by:	Gavin Mu
MFC after:	1 week
2012-06-04 20:45:33 +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 void 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 void
ofwd_print(int verbose __unused)
{
}