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freebsd/sys/scsi/worm.c
Peter Dufault 386d2d2de0 Change defintion of unit to minor(dev). Sorry for not
having this in my local build.  Thanks to gpalmer.
1995-05-03 23:53:32 +00:00

360 lines
9.2 KiB
C

/*
* worm: Write Once device driver
*
* Copyright (C) 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.
*
* $Id: worm.c,v 1.5 1995/05/03 23:38:20 gpalmer Exp $
*/
/* XXX This is PRELIMINARY.
*
* We need the "kern devconf" stuff, but I'm not
* going to add it until it is done in a simple way that provides
* base behavior in scsi_driver.c
*
* Until Bruce finishes the slice stuff there will be no partitions.
* When it is finished I hope to hoist the partition code up into
* "scsi_driver" and use common code for all devices.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <scsi/scsi_all.h>
#include <scsi/scsiconf.h>
#include <scsi/scsi_disk.h>
struct scsi_data {
struct buf *buf_queue; /* the queue of pending IO operations */
u_int32 n_blks; /* Number of blocks (0 for bogus) */
u_int32 blk_size; /* Size of each blocks */
};
void wormstart(u_int32 unit, u_int32 flags);
errval worm_open(dev_t dev, int flags, int fmt, struct proc *p,
struct scsi_link *sc_link);
errval worm_ioctl(dev_t dev, int cmd, caddr_t addr, int flag,
struct proc *p, struct scsi_link *sc_link);
errval worm_close(dev_t dev, int flag, int fmt, struct proc *p,
struct scsi_link *sc_link);
void worm_strategy(struct buf *bp, struct scsi_link *sc_link);
SCSI_DEVICE_ENTRIES(worm)
struct scsi_device worm_switch =
{
NULL,
wormstart, /* we have a queue, and this is how we service it */
NULL,
NULL,
"worm",
0,
{0, 0},
SDEV_ONCE_ONLY, /* Only one open allowed */
wormattach,
"Write-Once",
wormopen,
sizeof(struct scsi_data),
T_WORM,
0,
0,
worm_open,
0,
worm_close,
worm_strategy,
};
static int worm_size(struct scsi_link *sc_link)
{
int ret;
struct scsi_data *worm = sc_link->sd;
worm->n_blks = scsi_read_capacity(sc_link, &worm->blk_size,
SCSI_NOSLEEP | SCSI_NOMASK);
if (worm->n_blks)
{
sc_link->flags |= SDEV_MEDIA_LOADED;
ret = 1;
}
else
{
sc_link->flags &= ~SDEV_MEDIA_LOADED;
ret = 0;
}
return ret;
}
errval
wormattach(struct scsi_link *sc_link)
{
struct scsi_data *worm = sc_link->sd;
printf("- UNTESTED ");
if (worm_size(sc_link) == 0)
printf("- can't get capacity.");
else
printf("with %ld %ld byte blocks.", worm->n_blks, worm->blk_size);
return 0;
}
/*
* wormstart looks to see if there is a buf waiting for the device
* and that the device is not already busy. If both are true,
* It dequeues the buf and creates a scsi command to perform the
* transfer required. The transfer request will call scsi_done
* on completion, which will in turn call this routine again
* so that the next queued transfer is performed.
* The bufs are queued by the strategy routine (wormstrategy)
*
* This routine is also called after other non-queued requests
* have been made of the scsi driver, to ensure that the queue
* continues to be drained.
* wormstart() is called at splbio
*
* XXX It looks like we need a "scsistart" to hoist common code up
* into. In particular, the removable media checking should be
* handled in one place.
*/
void
wormstart(unit, flags)
u_int32 unit;
u_int32 flags;
{
struct scsi_link *sc_link = SCSI_LINK(&worm_switch, unit);
struct scsi_data *worm = sc_link->sd;
register struct buf *bp = 0;
struct
{
u_char op_code;
u_char byte2;
u_char lba3; /* I don't want to worry about packing */
u_char lba2;
u_char lba1;
u_char lba0;
u_char reserved;
u_char tl1;
u_char tl0;
u_char ctl;
} cmd;
u_int32 lba; /* Logical block address */
u_int32 tl; /* Transfer length */
SC_DEBUG(sc_link, SDEV_DB2, ("wormstart "));
/*
* We should reject all queued entries if SDEV_MEDIA_LOADED is not true.
*/
if (!(sc_link->flags & SDEV_MEDIA_LOADED)) {
goto badnews; /* no I/O.. media changed or something */
}
/*
* See if there is a buf to do and we are not already
* doing one
*/
while (sc_link->opennings != 0) {
/* if a special awaits, let it proceed first */
if (sc_link->flags & SDEV_WAITING) {
sc_link->flags &= ~SDEV_WAITING;
wakeup(sc_link);
return;
}
if ((bp = worm->buf_queue) == NULL) {
return; /* no work to bother with */
}
worm->buf_queue = bp->b_actf;
/*
* Fill out the scsi command
*/
bzero(&cmd, sizeof(cmd));
if ((bp->b_flags & B_READ) == B_WRITE) {
cmd.op_code = WRITE_BIG;
flags |= SCSI_DATA_OUT;
} else {
cmd.op_code = READ_BIG;
flags |= SCSI_DATA_IN;
}
lba = bp->b_blkno / (worm->blk_size / DEV_BSIZE);
tl = bp->b_bcount / worm->blk_size;
scsi_uto4b(lba, &cmd.lba3);
scsi_uto2b(tl, &cmd.tl1);
/*
* go ask the adapter to do all this for us
*/
if (scsi_scsi_cmd(sc_link,
(struct scsi_generic *) &cmd,
sizeof(cmd),
(u_char *) bp->b_un.b_addr,
bp->b_bcount,
0, /* can't retry a read on a tape really */
100000,
bp,
flags | SCSI_NOSLEEP) == SUCCESSFULLY_QUEUED) {
} else {
badnews:
printf("worm%ld: oops not queued\n", unit);
bp->b_flags |= B_ERROR;
bp->b_error = EIO;
biodone(bp);
}
} /* go back and see if we can cram more work in.. */
}
void
worm_strategy(struct buf *bp, struct scsi_link *sc_link)
{
struct buf **dp;
unsigned char unit;
u_int32 opri;
struct scsi_data *worm;
unit = minor((bp->b_dev));
worm = sc_link->sd;
/* XXX: Can't we move this check up to "scsi_strategy"?
*/
if (!(sc_link->flags & SDEV_MEDIA_LOADED) ||
bp->b_blkno > worm->n_blks ||
bp->b_bcount & (worm->blk_size - 1)) {
bp->b_error = EIO;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
opri = splbio();
/*
* Use a bounce buffer if necessary
* XXX: How can we move this up?
*/
#ifdef BOUNCE_BUFFERS
if (sc_link->flags & SDEV_BOUNCE)
vm_bounce_alloc(bp);
#endif
/*
* Place it in the queue of activities for this device
* at the end.
*/
dp = &(worm->buf_queue);
while (*dp) {
dp = &((*dp)->b_actf);
}
*dp = bp;
bp->b_actf = NULL;
wormstart(unit, 0);
splx(opri);
return;
}
/*
* Open the device. XXX: I'm completely guessing at this sequence.
*/
int
worm_open(dev_t dev, int flags, int fmt, struct proc *p,
struct scsi_link *sc_link)
{
if (sc_link->flags & SDEV_OPEN)
return EBUSY;
/*
* Check that it is still responding and ok.
* if the media has been changed this will result in a
* "unit attention" error which the error code will
* disregard because the SDEV_OPEN flag is not yet set
*
* XXX This should REALLY be hoisted up. As soon as Bruce
* finishes that slice stuff. (Add a different flag,
* and then do a "scsi_test_unit_ready" with the "ignore
* unit attention" thing set. Then all this replicated
* test unit ready code can be pulled up.
*/
scsi_test_unit_ready(sc_link, SCSI_SILENT);
/*
* Next time actually take notice of error returns
*/
sc_link->flags |= SDEV_OPEN; /* unit attn errors are now errors */
if (scsi_test_unit_ready(sc_link, SCSI_SILENT) != 0) {
SC_DEBUG(sc_link, SDEV_DB3, ("not ready\n"));
sc_link->flags &= ~SDEV_OPEN;
return ENXIO;
}
scsi_start_unit(sc_link, SCSI_SILENT);
scsi_prevent(sc_link, PR_PREVENT, SCSI_SILENT);
if (worm_size(sc_link) == 0) {
scsi_stop_unit(sc_link, 0, SCSI_SILENT);
scsi_prevent(sc_link, PR_ALLOW, SCSI_SILENT);
sc_link->flags &= ~SDEV_OPEN;
return ENXIO;
}
return 0;
}
int
worm_close(dev_t dev, int flag, int fmt, struct proc *p,
struct scsi_link *sc_link)
{
scsi_stop_unit(sc_link, 0, SCSI_SILENT);
scsi_prevent(sc_link, PR_ALLOW, SCSI_SILENT);
sc_link->flags &= ~SDEV_OPEN;
return 0;
}