freebsd-dev/sys/scsi/su.c
Jordan K. Hubbard 1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00

314 lines
7.5 KiB
C

/* su: SCSI Universal. This is a universal SCSI device that
* has a fixed minor number format. This allows you to refer
* to your devices by BUS, ID, LUN instead of st0, st1, ...
*
* This code looks up the underlying device for a given SCSI
* target and uses that driver.
*
*Begin copyright
*
* Copyright (C) 1993, 1994, 1995, HD Associates, Inc.
* PO Box 276
* Pepperell, MA 01463
* 508 433 5266
* dufault@hda.com
*
* This code is contributed to the University of California at Berkeley:
*
* 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.
*End copyright
*
* $FreeBSD$
*
* Tabstops 4
* XXX devfs entries for this device should be handled by generic scsiconfig
* Add a bdevsw interface.. ?
*/
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#ifdef DEVFS
#include <sys/devfsext.h>
#endif /*DEVFS*/
#include <scsi/scsiconf.h>
#define CDEV_MAJOR 18
/* These three used by ssc. */
extern d_open_t suopen;
extern d_close_t suclose;
extern d_ioctl_t suioctl;
static d_read_t suread;
static d_write_t suwrite;
static d_select_t suselect;
static d_strategy_t sustrategy;
static struct cdevsw su_cdevsw =
{ suopen, suclose, suread, suwrite, /*18*/
suioctl, nostop, nullreset, nodevtotty,/* scsi */
suselect, nommap, sustrategy, "su", NULL, -1 };
/* Build an old style device number (unit encoded in the minor number)
* from a base old one (no flag bits) and a full new one
* (BUS, LUN, TARG in the minor number, and flag bits).
*
* OLDDEV has the major number and device unit only. It was constructed
* at attach time and is stored in the scsi_link structure.
*
* NEWDEV can have whatever in it, but only the old control flags and the
* super bit are present. IT CAN'T HAVE ANY UNIT INFORMATION or you'll
* wind up with the wrong unit.
*/
#define OLD_DEV(NEWDEV, OLDDEV) ((OLDDEV) | ((NEWDEV) & 0x080000FF))
/* bnxio, cnxio: non existent device entries
*/
static struct bdevsw bnxio = {
nxopen,
nxclose,
nxstrategy,
nxioctl,
nxdump,
nxpsize,
0,
"NON",
NULL,
-1
};
static struct cdevsw cnxio = {
nxopen,
nxclose,
nxread,
nxwrite,
nxioctl,
nxstop,
nxreset,
nxdevtotty,
nxselect,
nxmmap,
nxstrategy,
"NON",
NULL,
-1
};
/* getsws: Look up the base dev switch for a given "by minor number" style
* device.
*/
static int
getsws(dev_t dev, int type,
struct bdevsw **bdevp, struct cdevsw **cdevp, dev_t *base)
{
int ret = 0;
struct scsi_link *scsi_link;
int chr_dev, blk_dev;
struct cdevsw *cdev;
struct bdevsw *bdev;
int bus = SCSI_BUS(dev),
lun = SCSI_LUN(dev),
id = SCSI_ID(dev);
/* Try to look up the base device by finding the major number in
* the scsi_link structure:
*/
if ((scsi_link = scsi_link_get(bus, id, lun)) == 0 ||
scsi_link->dev == NODEV)
{
ret = ENXIO;
/* XXX This assumes that you always have a character device if you
* have a block device. That seems reasonable.
*/
cdev = &cnxio;
chr_dev = NODEV;
bdev = &bnxio;
blk_dev = NODEV;
}
else
{
int bmaj, cmaj;
cmaj = major(scsi_link->dev);
cdev = cdevsw[cmaj];
chr_dev = OLD_DEV(dev, scsi_link->dev);
bmaj = chrtoblk(cmaj);
bdev = (bmaj == NODEV) ? &bnxio : bdevsw[bmaj];
blk_dev = OLD_DEV(dev, makedev(bmaj, minor(scsi_link->dev)));
}
if (cdevp)
*cdevp = cdev;
if (bdevp)
*bdevp = bdev;
if (type == S_IFCHR)
*base = chr_dev;
else
*base = blk_dev;
return ret;
}
int
suopen(dev_t dev, int flag, int type, struct proc *p)
{
struct cdevsw *cdev;
struct bdevsw *bdev;
dev_t base;
if (getsws(dev, type, &bdev, &cdev, &base))
{
/* Device not configured? Reprobe then try again.
*/
int bus = SCSI_BUS(dev), lun = SCSI_LUN(dev), id = SCSI_ID(dev);
if (scsi_probe_bus(bus, id, lun) || getsws(dev, type, &bdev, &cdev,
&base))
return ENXIO;
}
/* There is a properly configured underlying device.
* Synthesize an appropriate device number:
*/
if (type == S_IFCHR)
return (*cdev->d_open)(base, flag, S_IFCHR, p);
else
return (*bdev->d_open)(base, flag, S_IFBLK, p);
}
int
suclose(dev_t dev, int fflag, int type, struct proc *p)
{
struct cdevsw *cdev;
struct bdevsw *bdev;
dev_t base;
(void)getsws(dev, type, &bdev, &cdev, &base);
if (type == S_IFCHR)
return (*cdev->d_close)(base, fflag, S_IFCHR, p);
else
return (*bdev->d_open)(base, fflag, S_IFBLK, p);
}
static void
sustrategy(struct buf *bp)
{
dev_t base;
struct bdevsw *bdev;
dev_t dev = bp->b_dev;
/* XXX: I have no way of knowing if this was through the
* block or the character entry point.
*/
(void)getsws(dev, S_IFBLK, &bdev, 0, &base);
bp->b_dev = base;
(*bdev->d_strategy)(bp);
bp->b_dev = dev;
}
int
suioctl(dev_t dev, int cmd, caddr_t data, int fflag, struct proc *p)
{
struct cdevsw *cdev;
dev_t base;
/* XXX: I have no way of knowing if this was through the
* block or the character entry point.
*/
(void)getsws(dev, S_IFCHR, 0, &cdev, &base);
return (*cdev->d_ioctl)(base, cmd, data, fflag, p);
}
static int
suread(dev_t dev, struct uio *uio, int ioflag)
{
dev_t base;
struct cdevsw *cdev;
(void)getsws(dev, S_IFCHR, 0, &cdev, &base);
return (*cdev->d_read)(base, uio, ioflag);
}
static int
suwrite(dev_t dev, struct uio *uio, int ioflag)
{
dev_t base;
struct cdevsw *cdev;
(void)getsws(dev, S_IFCHR, 0, &cdev, &base);
return (*cdev->d_write)(base, uio, ioflag);
}
static int
suselect(dev_t dev, int which, struct proc *p)
{
dev_t base;
struct cdevsw *cdev;
(void)getsws(dev, S_IFCHR, 0, &cdev, &base);
return (*cdev->d_select)(base, which, p);
}
static su_devsw_installed = 0;
static void
su_drvinit(void *unused)
{
dev_t dev;
if( ! su_devsw_installed ) {
dev = makedev(CDEV_MAJOR, 0);
cdevsw_add(&dev,&su_cdevsw, NULL);
su_devsw_installed = 1;
}
}
SYSINIT(sudev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,su_drvinit,NULL)