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NetBSD/sys/arch/i386/isa/wd.c

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/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
*
* from:@(#)wd.c 7.2 (Berkeley) 5/9/91
*/
/* Note: This code heavily modified by tih@barsoom.nhh.no; use at own risk! */
/* The following defines represent only a very small part of the mods, most */
/* of them are not marked in any way. -tih */
#undef WDOPENLOCK /* Prevent reentrancy in wdopen() for testing */
#define TIHMODS /* wdopen() workaround, some splx() calls */
#define TIHBAD144 /* new bad144 bad sector handling */
#define QUIETWORKS /* define this when wdopen() can actually set DKFL_QUIET */
#define INSTRUMENT /* Add instrumentation stuff by Brad Parker */
/* TODO: peel out buffer at low ipl, speed improvement */
/* TODO: find and fix the timing bugs apparent on some controllers */
#include "wd.h"
#if NWDC > 0
#include "param.h"
#include "dkbad.h"
#include "systm.h"
#include "conf.h"
#include "file.h"
#include "stat.h"
#include "ioctl.h"
#include "disklabel.h"
#include "buf.h"
#include "uio.h"
#include "malloc.h"
#include "machine/cpu.h"
#ifdef INSTRUMENT
#include "sys/dkstat.h"
#endif
#include "i386/isa/isa.h"
#include "i386/isa/isa_device.h"
#include "i386/isa/icu.h"
#include "i386/isa/wdreg.h"
#include "syslog.h"
#include "vm/vm.h"
#define RETRIES 5 /* number of retries before giving up */
#define wdnoreloc(dev) (minor(dev) & 0x80) /* ignore partition table */
#define wddospart(dev) (minor(dev) & 0x40) /* use dos partitions */
#define wdunit(dev) ((minor(dev) & 0x38) >> 3)
#define wdpart(dev) (minor(dev) & 0x7)
#define makewddev(maj, unit, part) (makedev(maj,((unit<<3)+part)))
#define WDRAW 3 /* 'd' partition isn't a partition! */
#define b_cylin b_resid /* cylinder number for doing IO to */
/* shares an entry in the buf struct */
/*
* Drive states. Used to initialize drive.
*/
#define CLOSED 0 /* disk is closed. */
#define WANTOPEN 1 /* open requested, not started */
#define RECAL 2 /* doing restore */
#define OPEN 3 /* done with open */
/*
* The structure of a disk drive.
*/
struct disk {
long dk_bc; /* byte count left */
long dk_bct; /* total byte count left */
short dk_skip; /* blocks already transferred */
short dk_skipm; /* blocks already transferred for multi */
char dk_ctrlr; /* physical controller number */
char dk_unit; /* physical unit number */
char dk_lunit; /* logical unit number */
char dk_state; /* control state */
u_char dk_status; /* copy of status reg. */
u_char dk_error; /* copy of error reg. */
short dk_port; /* i/o port base */
u_long dk_copenpart; /* character units open on this drive */
u_long dk_bopenpart; /* block units open on this drive */
u_long dk_openpart; /* all units open on this drive */
short dk_wlabel; /* label writable? */
short dk_flags; /* drive characteistics found */
#define DKFL_DOSPART 0x00001 /* has DOS partition table */
#define DKFL_QUIET 0x00002 /* report errors back, but don't complain */
#define DKFL_SINGLE 0x00004 /* sector at a time mode */
#define DKFL_ERROR 0x00008 /* processing a disk error */
#define DKFL_BSDLABEL 0x00010 /* has a BSD disk label */
#define DKFL_BADSECT 0x00020 /* has a bad144 badsector table */
#define DKFL_WRITEPROT 0x00040 /* manual unit write protect */
struct wdparams dk_params; /* ESDI/IDE drive/controller parameters */
struct disklabel dk_dd; /* device configuration data */
struct dos_partition
dk_dospartitions[NDOSPART]; /* DOS view of disk */
struct dkbad dk_bad; /* bad sector table */
#ifdef TIHBAD144
long dk_badsect[127]; /* 126 plus trailing -1 marker */
#endif
};
#ifdef TIHBAD144
void bad144intern(struct disk *);
#endif
void wddisksort();
struct disk *wddrives[NWD]; /* table of units */
struct buf wdtab[NWDC]; /* various per-controller info */
struct buf wdutab[NWD]; /* head of queue per drive */
struct buf rwdbuf[NWD]; /* buffers for raw IO */
long wdxfer[NWD]; /* count of transfers */
#ifdef WDOPENLOCK
int wdopenbusy = 0;
#endif
int wdprobe(), wdattach();
struct isa_driver wdcdriver = {
wdprobe, wdattach, "wdc",
};
void wdustart(struct disk *);
void wdstart(int);
int wdcommand(struct disk *, int);
int wdcontrol(struct buf *);
int wdsetctlr(dev_t, struct disk *);
int wdgetctlr(int, struct disk *);
/*
* Probe for controller.
*/
int
wdprobe(struct isa_device *dvp)
{
struct disk *du;
int wdc;
#ifdef WDOPENLOCK
wdopenbusy = 0;
#endif
if (dvp->id_unit >= NWDC)
return(0);
du = (struct disk *) malloc (sizeof(struct disk), M_TEMP, M_NOWAIT);
bzero(du, sizeof(struct disk));
du->dk_ctrlr = dvp->id_unit;
du->dk_unit = 0;
du->dk_lunit = 0;
wdc = du->dk_port = dvp->id_iobase;
/* check if we have registers that work */
outb(wdc+wd_error, 0x5a); /* error register not writable */
outb(wdc+wd_cyl_lo, 0xa5); /* but all of cyllo are implemented */
if(inb(wdc+wd_error) == 0x5a || inb(wdc+wd_cyl_lo) != 0xa5)
goto nodevice;
/* reset the device */
outb(wdc+wd_ctlr, (WDCTL_RST|WDCTL_IDS));
DELAY(1000);
outb(wdc+wd_ctlr, WDCTL_IDS);
DELAY(1000);
/* execute a controller only command */
if (wdcommand(du, WDCC_DIAGNOSE) < 0)
goto nodevice;
(void) inb(wdc+wd_error); /* XXX! */
outb(wdc+wd_ctlr, WDCTL_4BIT);
DELAY(1000);
bzero(&wdtab[du->dk_ctrlr], sizeof(struct buf));
free(du, M_TEMP);
return (1);
nodevice:
free(du, M_TEMP);
return (0);
}
/*
* Attach each drive if possible.
*/
int
wdattach(struct isa_device *dvp)
{
int unit, lunit;
extern struct isa_device isa_biotab_wdc[];
struct isa_device *wdup;
struct disk *du;
int first = 0;
if (dvp->id_unit >= NWDC)
return(0);
for (wdup = isa_biotab_wdc; wdup->id_driver != 0; wdup++) {
if (wdup->id_iobase != dvp->id_iobase)
continue;
lunit = wdup->id_unit;
if (lunit >= NWD)
continue;
unit = wdup->id_physid;
du = wddrives[lunit] = (struct disk *)
malloc(sizeof(struct disk), M_TEMP, M_NOWAIT);
bzero(du, sizeof(struct disk));
bzero(&wdutab[lunit], sizeof(struct buf));
bzero(&rwdbuf[lunit], sizeof(struct buf));
wdxfer[lunit] = 0;
du->dk_ctrlr = dvp->id_unit;
du->dk_unit = unit;
du->dk_lunit = lunit;
du->dk_port = dvp->id_iobase;
if(wdgetctlr(unit, du) == 0) {
int i, blank;
if(first==0) {
first = 1;
printf("wdc%d: <", dvp->id_unit);
for (i=blank=0; i<sizeof(du->dk_params.wdp_model); i++) {
char c = du->dk_params.wdp_model[i];
if (blank && c == ' ')
continue;
if (blank && c != ' ') {
printf(" %c", c);
blank = 0;
continue;
}
if (c == ' ')
blank = 1;
else
printf("%c", c);
}
printf(">\n");
}
printf("wd%d at wdc%d slave %d\n", lunit, dvp->id_unit, unit);
} else {
/*printf("wd%d at wdc%d slave %d -- error\n",
lunit, dvp->id_unit, unit);*/
wddrives[lunit] = 0;
free(du, M_TEMP);
}
}
return(1);
}
/* Read/write routine for a buffer. Finds the proper unit, range checks
* arguments, and schedules the transfer. Does not wait for the transfer
* to complete. Multi-page transfers are supported. All I/O requests must
* be a multiple of a sector in length.
*/
int
wdstrategy(register struct buf *bp)
{
register struct buf *dp;
struct disk *du; /* Disk unit to do the IO. */
int lunit = wdunit(bp->b_dev);
int s;
/* valid unit, controller, and request? */
if (lunit >= NWD || bp->b_blkno < 0 ||
howmany(bp->b_bcount, DEV_BSIZE) >= (1<<NBBY) ||
(du = wddrives[lunit]) == 0) {
bp->b_error = EINVAL;
bp->b_flags |= B_ERROR;
goto done;
}
/* "soft" write protect check */
if ((du->dk_flags & DKFL_WRITEPROT) && (bp->b_flags & B_READ) == 0) {
bp->b_error = EROFS;
bp->b_flags |= B_ERROR;
goto done;
}
/* have partitions and want to use them? */
if ((du->dk_flags & DKFL_BSDLABEL) != 0 && wdpart(bp->b_dev) != WDRAW) {
/*
* do bounds checking, adjust transfer. if error, process.
* if end of partition, just return
*/
if (bounds_check_with_label(bp, &du->dk_dd, du->dk_wlabel) <= 0)
goto done;
/* otherwise, process transfer request */
}
/* queue transfer on drive, activate drive and controller if idle */
dp = &wdutab[lunit];
s = splbio();
wddisksort(dp, bp);
if (dp->b_active == 0)
wdustart(du); /* start drive */
if (wdtab[du->dk_ctrlr].b_active == 0)
wdstart(du->dk_ctrlr); /* start controller */
splx(s);
return 0;
done:
/* toss transfer, we're done early */
biodone(bp);
return 0;
}
/*
* Routine to queue a command to the controller. The unit's
* request is linked into the active list for the controller.
* If the controller is idle, the transfer is started.
*/
static void
wdustart(register struct disk *du)
{
register struct buf *bp, *dp = &wdutab[du->dk_lunit];
int ctrlr = du->dk_ctrlr;
/* unit already active? */
if (dp->b_active)
return;
/* anything to start? */
bp = dp->b_actf;
if (bp == NULL)
return;
/* link onto controller queue */
dp->b_forw = NULL;
if (wdtab[ctrlr].b_actf == NULL)
wdtab[ctrlr].b_actf = dp;
else
wdtab[ctrlr].b_actl->b_forw = dp;
wdtab[ctrlr].b_actl = dp;
/* mark the drive unit as busy */
dp->b_active = 1;
}
/*
* Controller startup routine. This does the calculation, and starts
* a single-sector read or write operation. Called to start a transfer,
* or from the interrupt routine to continue a multi-sector transfer.
* RESTRICTIONS:
* 1. The transfer length must be an exact multiple of the sector size.
*/
static void
wdstart(int ctrlr)
{
register struct disk *du; /* disk unit for IO */
register struct buf *bp;
struct disklabel *lp;
struct buf *dp;
long blknum, cylin, head, sector;
long secpertrk, secpercyl, addr;
int lunit, wdc;
int xfrblknum;
unsigned char status;
loop:
/* is there a drive for the controller to do a transfer with? */
dp = wdtab[ctrlr].b_actf;
if (dp == NULL)
return;
/* is there a transfer to this drive ? if so, link it on
the controller's queue */
bp = dp->b_actf;
if (bp == NULL) {
wdtab[ctrlr].b_actf = dp->b_forw;
goto loop;
}
/* obtain controller and drive information */
lunit = wdunit(bp->b_dev);
du = wddrives[lunit];
/* if not really a transfer, do control operations specially */
if (du->dk_state < OPEN) {
(void) wdcontrol(bp);
return;
}
/* calculate transfer details */
blknum = bp->b_blkno + du->dk_skip;
#ifdef WDDEBUG
if (du->dk_skip == 0)
printf("\nwdstart %d: %s %d@%d; map ", lunit,
(bp->b_flags & B_READ) ? "read" : "write",
bp->b_bcount, blknum);
else
printf(" %d)%x", du->dk_skip, inb(du->dk_port+wd_altsts));
#endif
addr = (int) bp->b_un.b_addr;
if (du->dk_skip == 0) {
du->dk_bc = bp->b_bcount;
}
if (du->dk_skipm == 0) {
struct buf *oldbp, *nextbp;
oldbp = bp;
nextbp = bp->av_forw;
du->dk_bct = du->dk_bc;
oldbp->b_flags |= B_XXX;
while( nextbp
&& (oldbp->b_flags & DKFL_SINGLE) == 0
&& oldbp->b_dev == nextbp->b_dev
&& nextbp->b_blkno == (oldbp->b_blkno + (oldbp->b_bcount/DEV_BSIZE))
&& (oldbp->b_flags & B_READ) == (nextbp->b_flags & B_READ)) {
if( (du->dk_bct+nextbp->b_bcount)/DEV_BSIZE >= 240) {
break;
}
du->dk_bct += nextbp->b_bcount;
oldbp->b_flags |= B_XXX;
oldbp = nextbp;
nextbp = nextbp->av_forw;
}
}
lp = &du->dk_dd;
secpertrk = lp->d_nsectors;
secpercyl = lp->d_secpercyl;
if ((du->dk_flags & DKFL_BSDLABEL) != 0 && wdpart(bp->b_dev) != WDRAW)
blknum += lp->d_partitions[wdpart(bp->b_dev)].p_offset;
cylin = blknum / secpercyl;
head = (blknum % secpercyl) / secpertrk;
sector = blknum % secpertrk;
#ifdef TIHBAD144
/* Check for bad sectors if we have them, and not formatting */
/* Only do this in single-sector mode, or when starting a */
/* multiple-sector transfer. */
#ifdef B_FORMAT
if ((du->dk_flags & DKFL_BADSECT) && !(bp->b_flags & B_FORMAT) &&
((du->dk_skipm == 0) || (du->dk_flags & DKFL_SINGLE))) {
#else
if ((du->dk_flags & DKFL_BADSECT) &&
((du->dk_skipm == 0) || (du->dk_flags & DKFL_SINGLE))) {
#endif
long blkchk, blkend, blknew;
int i;
blkend = blknum + howmany(du->dk_bct, DEV_BSIZE) - 1;
for (i = 0; (blkchk = du->dk_badsect[i]) != -1; i++) {
if (blkchk > blkend) {
break; /* transfer is completely OK; done */
} else if (blkchk == blknum) {
blknew = lp->d_secperunit - lp->d_nsectors - i - 1;
cylin = blknew / secpercyl;
head = (blknew % secpercyl) / secpertrk;
sector = blknew % secpertrk;
du->dk_flags |= DKFL_SINGLE;
/* found and replaced first blk of transfer; done */
break;
} else if (blkchk > blknum) {
du->dk_flags |= DKFL_SINGLE;
break; /* bad block inside transfer; done */
}
}
}
#endif
if( du->dk_flags & DKFL_SINGLE) {
du->dk_bct = du->dk_bc;
du->dk_skipm = du->dk_skip;
}
#ifdef WDDEBUG
pg("c%d h%d s%d ", cylin, head, sector);
#endif
sector += 1; /* sectors begin with 1, not 0 */
wdtab[ctrlr].b_active = 1; /* mark controller active */
wdc = du->dk_port;
#ifdef INSTRUMENT
/* instrumentation */
if (du->dk_unit >= 0 && du->dk_skip == 0) {
dk_busy |= 1 << du->dk_lunit;
dk_wds[du->dk_lunit] += bp->b_bcount >> 6;
}
if (du->dk_unit >= 0 && du->dk_skipm == 0) {
++dk_seek[du->dk_lunit];
++dk_xfer[du->dk_lunit];
}
#endif
/* if starting a multisector transfer, or doing single transfers */
if (du->dk_skipm == 0 || (du->dk_flags & DKFL_SINGLE)) {
if (wdtab[ctrlr].b_errcnt && (bp->b_flags & B_READ) == 0) {
du->dk_bc += DEV_BSIZE;
du->dk_bct += DEV_BSIZE;
}
/* controller idle? */
while (inb(wdc+wd_status) & WDCS_BUSY)
;
/* stuff the task file */
outb(wdc+wd_precomp, lp->d_precompcyl / 4);
#ifdef B_FORMAT
if (bp->b_flags & B_FORMAT) {
outb(wdc+wd_sector, lp->d_gap3);
outb(wdc+wd_seccnt, lp->d_nsectors);
} else {
if (du->dk_flags & DKFL_SINGLE)
outb(wdc+wd_seccnt, 1);
else
outb(wdc+wd_seccnt, howmany(du->dk_bct, DEV_BSIZE));
outb(wdc+wd_sector, sector);
}
#else
if (du->dk_flags & DKFL_SINGLE)
outb(wdc+wd_seccnt, 1);
else
outb(wdc+wd_seccnt, howmany(du->dk_bct, DEV_BSIZE));
outb(wdc+wd_sector, sector);
#endif
outb(wdc+wd_cyl_lo, cylin);
outb(wdc+wd_cyl_hi, cylin >> 8);
/* set up the SDH register (select drive) */
outb(wdc+wd_sdh, WDSD_IBM | (du->dk_unit<<4) | (head & 0xf));
/* wait for drive to become ready */
while ((inb(wdc+wd_status) & WDCS_READY) == 0)
;
/* initiate command! */
#ifdef B_FORMAT
if (bp->b_flags & B_FORMAT)
outb(wdc+wd_command, WDCC_FORMAT);
else
outb(wdc+wd_command,
(bp->b_flags & B_READ)? WDCC_READ : WDCC_WRITE);
#else
outb(wdc+wd_command, (bp->b_flags & B_READ)? WDCC_READ : WDCC_WRITE);
#endif
#ifdef WDDEBUG
printf("sector %d cylin %d head %d addr %x sts %x\n",
sector, cylin, head, addr, inb(wdc+wd_altsts));
#endif
}
/* if this is a read operation, just go away until it's done. */
if (bp->b_flags & B_READ)
return;
/* ready to send data? */
while ((inb(wdc+wd_altsts) & WDCS_DRQ) == 0)
;
/* then send it! */
outagain:
outsw (wdc+wd_data, addr+du->dk_skip * DEV_BSIZE,
DEV_BSIZE/sizeof(short));
du->dk_bc -= DEV_BSIZE;
du->dk_bct -= DEV_BSIZE;
}
/* Interrupt routine for the controller. Acknowledge the interrupt, check for
* errors on the current operation, mark it done if necessary, and start
* the next request. Also check for a partially done transfer, and
* continue with the next chunk if so.
*/
void
wdintr(struct intrframe wdif)
{
register struct disk *du;
register struct buf *bp, *dp;
int status, wdc, ctrlr;
ctrlr = wdif.if_vec;
if (!wdtab[ctrlr].b_active) {
printf("wdc%d: extra interrupt\n", ctrlr);
return;
}
dp = wdtab[ctrlr].b_actf;
bp = dp->b_actf;
du = wddrives[wdunit(bp->b_dev)];
wdc = du->dk_port;
#ifdef WDDEBUG
printf("I%d ", ctrlr);
#endif
while ((status = inb(wdc+wd_status)) & WDCS_BUSY)
;
/* is it not a transfer, but a control operation? */
if (du->dk_state < OPEN) {
if (wdcontrol(bp))
wdstart(ctrlr);
return;
}
/* have we an error? */
if (status & (WDCS_ERR | WDCS_ECCCOR)) {
du->dk_status = status;
du->dk_error = inb(wdc + wd_error);
#ifdef WDDEBUG
printf("status %x error %x\n", status, du->dk_error);
#endif
if((du->dk_flags & DKFL_SINGLE) == 0) {
du->dk_flags |= DKFL_ERROR;
goto outt;
}
#ifdef B_FORMAT
if (bp->b_flags & B_FORMAT) {
bp->b_flags |= B_ERROR;
goto done;
}
#endif
/* error or error correction? */
if (status & WDCS_ERR) {
if (++wdtab[ctrlr].b_errcnt < RETRIES) {
wdtab[ctrlr].b_active = 0;
} else {
if((du->dk_flags & DKFL_QUIET) == 0) {
diskerr(bp, "wd", "hard error",
LOG_PRINTF, du->dk_skip,
&du->dk_dd);
#ifdef WDDEBUG
printf( "status %b error %b\n",
status, WDCS_BITS,
inb(wdc+wd_error), WDERR_BITS);
#endif
}
bp->b_flags |= B_ERROR; /* flag the error */
}
} else if((du->dk_flags & DKFL_QUIET) == 0) {
diskerr(bp, "wd", "soft ecc", 0,
du->dk_skip, &du->dk_dd);
}
}
outt:
/*
* If this was a successful read operation, fetch the data.
*/
if (((bp->b_flags & (B_READ | B_ERROR)) == B_READ) && wdtab[ctrlr].b_active) {
int chk, dummy;
chk = min(DEV_BSIZE / sizeof(short), du->dk_bc / sizeof(short));
/* ready to receive data? */
while ((inb(wdc+wd_status) & WDCS_DRQ) == 0)
;
/* suck in data */
insw (wdc+wd_data,
(int)bp->b_un.b_addr + du->dk_skip * DEV_BSIZE, chk);
du->dk_bc -= chk * sizeof(short);
du->dk_bct -= chk * sizeof(short);
/* for obselete fractional sector reads */
while (chk++ < (DEV_BSIZE / sizeof(short)))
insw(wdc+wd_data, &dummy, 1);
}
wdxfer[du->dk_lunit]++;
if (wdtab[ctrlr].b_active) {
#ifdef INSTRUMENT
if (du->dk_unit >= 0)
dk_busy &=~ (1 << du->dk_unit);
#endif
if ((bp->b_flags & B_ERROR) == 0) {
du->dk_skip++; /* Add to succ. sect */
du->dk_skipm++; /* Add to succ. sect for multitransfer */
if (wdtab[ctrlr].b_errcnt && (du->dk_flags & DKFL_QUIET) == 0)
diskerr(bp, "wd", "soft error", 0,
du->dk_skip, &du->dk_dd);
wdtab[ctrlr].b_errcnt = 0;
/* see if more to transfer */
if (du->dk_bc > 0 && (du->dk_flags & DKFL_ERROR) == 0) {
if( (du->dk_flags & DKFL_SINGLE)
|| (du->dk_flags & B_READ) == 0)
wdstart(ctrlr);
return; /* next chunk is started */
} else if ((du->dk_flags & (DKFL_SINGLE|DKFL_ERROR)) == DKFL_ERROR) {
du->dk_skip = 0;
du->dk_skipm = 0;
du->dk_flags &= ~DKFL_ERROR;
du->dk_flags |= DKFL_SINGLE;
wdstart(ctrlr);
return; /* redo xfer sector by sector */
}
}
done:
/* done with this transfer, with or without error */
du->dk_flags &= ~DKFL_SINGLE;
wdtab[ctrlr].b_errcnt = 0;
du->dk_skip = 0;
if( du->dk_bct == 0) {
wdtab[ctrlr].b_actf = dp->b_forw;
du->dk_skipm = 0;
dp->b_active = 0;
}
dp->b_actf = bp->av_forw;
dp->b_errcnt = 0;
bp->b_resid = 0;
bp->b_flags &= ~B_XXX;
biodone(bp);
}
/* anything more on drive queue? */
if (dp->b_actf && du->dk_bct == 0)
wdustart(du);
/* anything more for controller to do? */
if (wdtab[ctrlr].b_actf)
wdstart(ctrlr);
if (!wdtab[ctrlr].b_actf)
wdtab[ctrlr].b_active = 0;
}
/*
* Initialize a drive.
*/
int
wdopen(dev_t dev, int flags, int fmt, struct proc *p)
{
register unsigned int lunit;
register struct disk *du;
int part = wdpart(dev), mask = 1 << part;
struct partition *pp;
int error = 0;
char *msg;
lunit = wdunit(dev);
if (lunit >= NWD)
return (ENXIO);
du = wddrives[lunit];
if (du == 0)
return (ENXIO);
#ifdef WDOPENLOCK
printf("[Enter wd%d%c]\n", lunit, part+'a');
if (wdopenbusy) {
printf("[Sleep wd%d%c]\n", lunit, part+'a');
while (wdopenbusy)
;
}
printf("[Lock wd%d%c]\n", lunit, part+'a');
wdopenbusy = 1;
#endif
#ifdef QUIETWORKS
if (part == WDRAW)
du->dk_flags |= DKFL_QUIET;
else
du->dk_flags &= ~DKFL_QUIET;
#else
du->dk_flags &= ~DKFL_QUIET;
#endif
if ((du->dk_flags & DKFL_BSDLABEL) == 0) {
du->dk_flags |= DKFL_WRITEPROT;
#ifdef WDOPENLOCK
printf("[Init wd%d%c]\n", lunit, part+'a');
#endif
wdutab[lunit].b_actf = NULL;
/*
* Use the default sizes until we've read the label,
* or longer if there isn't one there.
*/
bzero(&du->dk_dd, sizeof(du->dk_dd));
#undef d_type /* fix goddamn segments.h! XXX */
du->dk_dd.d_type = DTYPE_ST506;
du->dk_dd.d_ncylinders = 1024;
du->dk_dd.d_secsize = DEV_BSIZE;
du->dk_dd.d_ntracks = 8;
du->dk_dd.d_nsectors = 17;
du->dk_dd.d_secpercyl = 17*8;
du->dk_dd.d_secperunit = 17*8*1024;
du->dk_state = WANTOPEN;
/* read label using "raw" partition */
#if defined(TIHMODS) && defined(garbage)
/* wdsetctlr(dev, du); */ /* Maybe do this TIH */
msg = readdisklabel(makewddev(major(dev), wdunit(dev), WDRAW),
wdstrategy, &du->dk_dd, du->dk_dospartitions,
0, 0);
wdsetctlr(dev, du);
msg = readdisklabel(makewddev(major(dev), wdunit(dev), WDRAW),
wdstrategy, &du->dk_dd, du->dk_dospartitions,
&du->dk_bad, 0);
if (msg) {
#ifdef QUIETWORKS
if((du->dk_flags & DKFL_QUIET) == 0) {
log(LOG_WARNING, "wd%d: cannot find label (%s)\n",
lunit, msg);
error = EINVAL; /* XXX needs translation */
}
#else
log(LOG_WARNING, "wd%d: cannot find label (%s)\n", lunit, msg);
if(part != WDRAW) {
error = EINVAL; /* XXX needs translation */
}
#endif
goto done;
} else {
wdsetctlr(dev, du);
du->dk_flags |= DKFL_BSDLABEL;
du->dk_flags &= ~DKFL_WRITEPROT;
if (du->dk_dd.d_flags & D_BADSECT)
du->dk_flags |= DKFL_BADSECT;
}
#else
if (msg = readdisklabel(makewddev(major(dev), wdunit(dev), WDRAW),
wdstrategy, &du->dk_dd, du->dk_dospartitions,
&du->dk_bad, 0)) {
if((du->dk_flags & DKFL_QUIET) == 0) {
log(LOG_WARNING, "wd%d: cannot find label (%s)\n",
lunit, msg);
error = EINVAL; /* XXX needs translation */
}
goto done;
} else {
wdsetctlr(dev, du);
du->dk_flags |= DKFL_BSDLABEL;
du->dk_flags &= ~DKFL_WRITEPROT;
if (du->dk_dd.d_flags & D_BADSECT)
du->dk_flags |= DKFL_BADSECT;
}
#endif
done:
if (error) {
#ifdef WDOPENLOCK
printf("[Error wd%d%c]\n", lunit, part+'a');
wdopenbusy = 0;
#endif
return(error);
}
}
#ifdef TIHBAD144
if (du->dk_flags & DKFL_BADSECT)
bad144intern(du);
#endif
/*
* Warn if a partion is opened
* that overlaps another partition which is open
* unless one is the "raw" partition (whole disk).
*/
if ((du->dk_openpart & mask) == 0 /*&& part != RAWPART*/ && part != WDRAW) {
int start, end;
pp = &du->dk_dd.d_partitions[part];
start = pp->p_offset;
end = pp->p_offset + pp->p_size;
for (pp = du->dk_dd.d_partitions;
pp < &du->dk_dd.d_partitions[du->dk_dd.d_npartitions]; pp++) {
if (pp->p_offset + pp->p_size <= start || pp->p_offset >= end)
continue;
/*if (pp - du->dk_dd.d_partitions == RAWPART)
continue; */
if (pp - du->dk_dd.d_partitions == WDRAW)
continue;
if (du->dk_openpart & (1 << (pp - du->dk_dd.d_partitions)))
log(LOG_WARNING,
"wd%d%c: overlaps open partition (%c)\n",
lunit, part + 'a',
pp - du->dk_dd.d_partitions + 'a');
}
}
if (part >= du->dk_dd.d_npartitions && part != WDRAW) {
#ifdef WDOPENLOCK
printf("[ENXIO wd%d%c]\n", lunit, part+'a');
wdopenbusy = 0;
#endif
return (ENXIO);
}
/* insure only one open at a time */
du->dk_openpart |= mask;
switch (fmt) {
case S_IFCHR:
du->dk_copenpart |= mask;
break;
case S_IFBLK:
du->dk_bopenpart |= mask;
break;
}
#ifdef WDOPENLOCK
printf("[Done wd%d%c]\n", lunit, part+'a');
wdopenbusy = 0;
#endif
return (0);
}
/*
* Implement operations other than read/write.
* Called from wdstart or wdintr during opens and formats.
* Uses finite-state-machine to track progress of operation in progress.
* Returns 0 if operation still in progress, 1 if completed.
*/
static int
wdcontrol(register struct buf *bp)
{
register struct disk *du;
register unit, lunit;
unsigned char stat;
int s, ctrlr;
int wdc;
du = wddrives[wdunit(bp->b_dev)];
ctrlr = du->dk_ctrlr;
unit = du->dk_unit;
lunit = du->dk_lunit;
wdc = du->dk_port;
switch (du->dk_state) {
tryagainrecal:
case WANTOPEN: /* set SDH, step rate, do restore */
#ifdef WDDEBUG
printf("wd%d: recal ", lunit);
#endif
s = splbio(); /* not called from intr level ... */
wdgetctlr(unit, du);
#ifdef TIPCAT
while ((inb(wdc+wd_status) & WDCS_READY) == 0)
;
#endif
outb(wdc+wd_sdh, WDSD_IBM | (unit << 4));
wdtab[ctrlr].b_active = 1;
outb(wdc+wd_command, WDCC_RESTORE | WD_STEP);
#ifdef TIPCAT
while ((inb(wdc+wd_status) & WDCS_READY) == 0)
;
#endif
du->dk_state = RECAL;
splx(s);
return(0);
case RECAL:
if ((stat = inb(wdc+wd_status)) & WDCS_ERR) {
if ((du->dk_flags & DKFL_QUIET) == 0) {
printf("wd%d: recal", du->dk_lunit);
printf(": status %b error %b\n",
stat, WDCS_BITS, inb(wdc+wd_error),
WDERR_BITS);
}
if (++wdtab[ctrlr].b_errcnt < RETRIES)
goto tryagainrecal;
bp->b_error = ENXIO; /* XXX needs translation */
goto badopen;
}
/* some controllers require this ... */
wdsetctlr(bp->b_dev, du);
wdtab[ctrlr].b_errcnt = 0;
du->dk_state = OPEN;
/*
* The rest of the initialization can be done
* by normal means.
*/
return(1);
default:
panic("wdcontrol");
}
/* NOTREACHED */
badopen:
if ((du->dk_flags & DKFL_QUIET) == 0)
printf(": status %b error %b\n",
stat, WDCS_BITS, inb(wdc + wd_error), WDERR_BITS);
bp->b_flags |= B_ERROR;
return(1);
}
/*
* send a command and wait uninterruptibly until controller is finished.
* return -1 if controller busy for too long, otherwise
* return status. intended for brief controller commands at critical points.
* assumes interrupts are blocked.
*/
static int
wdcommand(struct disk *du, int cmd)
{
int timeout = 5000000, stat, wdc;
DELAY(2000);
/* controller ready for command? */
wdc = du->dk_port;
while (((stat = inb(wdc + wd_status)) & WDCS_BUSY) && timeout > 0)
timeout--;
if (timeout <= 0)
return(-1);
/* send command, await results */
outb(wdc+wd_command, cmd);
while (((stat = inb(wdc+wd_status)) & WDCS_BUSY) && timeout > 0)
timeout--;
if (timeout <= 0)
return(-1);
if (cmd != WDCC_READP)
return (stat);
/* is controller ready to return data? */
while (((stat = inb(wdc+wd_status)) & (WDCS_ERR|WDCS_DRQ)) == 0 &&
timeout > 0)
timeout--;
if (timeout <= 0)
return(-1);
return (stat);
}
/*
* issue IDC to drive to tell it just what geometry it is to be.
*/
static int
wdsetctlr(dev_t dev, struct disk *du)
{
int stat, x, wdc;
/*
printf("wd(%d,%d) C%dH%dS%d\n", du->dk_ctrlr, du->dk_unit,
du->dk_dd.d_ncylinders, du->dk_dd.d_ntracks, du->dk_dd.d_nsectors);
*/
DELAY(2000);
x = splbio();
wdc = du->dk_port;
outb(wdc+wd_cyl_lo, du->dk_dd.d_ncylinders); /* TIH: was ...ders+1 */
outb(wdc+wd_cyl_hi, (du->dk_dd.d_ncylinders)>>8); /* TIH: was ...ders+1 */
outb(wdc+wd_sdh, WDSD_IBM | (du->dk_unit << 4) + du->dk_dd.d_ntracks-1);
outb(wdc+wd_seccnt, du->dk_dd.d_nsectors);
stat = wdcommand(du, WDCC_IDC);
#ifndef TIHMODS
if (stat < 0)
return(stat);
#endif
if (stat & WDCS_ERR)
printf("wdsetctlr: status %b error %b\n",
stat, WDCS_BITS, inb(wdc+wd_error), WDERR_BITS);
splx(x);
return(stat);
}
/*
* issue READP to drive to ask it what it is.
*/
static int
wdgetctlr(int u, struct disk *du)
{
int stat, x, i, wdc;
char tb[DEV_BSIZE];
struct wdparams *wp;
long timeout = 5000000;
x = splbio(); /* not called from intr level ... */
wdc = du->dk_port;
#ifdef TIPCAT
while ((inb(wdc+wd_status) & WDCS_READY) == 0 && timeout > 0)
timeout--;
if (timeout <= 0) {
splx(x);
return (-1);
}
#endif
outb(wdc+wd_sdh, WDSD_IBM | (u << 4));
stat = wdcommand(du, WDCC_READP);
#ifdef TIPCAT
while ((inb(wdc+wd_status) & WDCS_READY) == 0 && timeout > 0)
timeout--;
if (timeout <= 0) {
splx(x);
return (-1);
}
#endif
#ifndef TIHMODS
if (stat < 0)
return(stat);
#else
if (stat < 0) {
splx(x);
return(stat);
}
#endif
if (stat & WDCS_ERR) {
splx(x);
return(inb(wdc+wd_error));
}
/* obtain parameters */
wp = &du->dk_params;
insw(wdc+wd_data, tb, sizeof(tb)/sizeof(short));
bcopy(tb, wp, sizeof(struct wdparams));
/* shuffle string byte order */
for (i=0; i < sizeof(wp->wdp_model); i+=2) {
u_short *p;
p = (u_short *) (wp->wdp_model + i);
*p = ntohs(*p);
}
/*
printf("gc %x cyl %d trk %d sec %d type %d sz %d model %s\n", wp->wdp_config,
wp->wdp_fixedcyl+wp->wdp_removcyl, wp->wdp_heads, wp->wdp_sectors,
wp->wdp_cntype, wp->wdp_cnsbsz, wp->wdp_model);
*/
/* update disklabel given drive information */
du->dk_dd.d_ncylinders = wp->wdp_fixedcyl + wp->wdp_removcyl /*+- 1*/;
du->dk_dd.d_ntracks = wp->wdp_heads;
du->dk_dd.d_nsectors = wp->wdp_sectors;
du->dk_dd.d_secpercyl = du->dk_dd.d_ntracks * du->dk_dd.d_nsectors;
du->dk_dd.d_partitions[1].p_size = du->dk_dd.d_secpercyl * wp->wdp_sectors;
du->dk_dd.d_partitions[1].p_offset = 0;
/* dubious ... */
bcopy("ESDI/IDE", du->dk_dd.d_typename, 9);
bcopy(wp->wdp_model+20, du->dk_dd.d_packname, 14-1);
/* better ... */
du->dk_dd.d_type = DTYPE_ESDI;
du->dk_dd.d_subtype |= DSTYPE_GEOMETRY;
/* XXX sometimes possibly needed */
(void) inb(wdc+wd_status);
#ifdef TIHMODS
splx(x);
#endif
return (0);
}
/* ARGSUSED */
int
wdclose(dev_t dev, int flags, int fmt)
{
register struct disk *du;
int part = wdpart(dev), mask = 1 << part;
du = wddrives[wdunit(dev)];
/* insure only one open at a time */
du->dk_openpart &= ~mask;
switch (fmt) {
case S_IFCHR:
du->dk_copenpart &= ~mask;
break;
case S_IFBLK:
du->dk_bopenpart &= ~mask;
break;
}
return(0);
}
int
wdioctl(dev_t dev, int cmd, caddr_t addr, int flag)
{
int lunit = wdunit(dev);
register struct disk *du;
int error = 0;
struct uio auio;
struct iovec aiov;
du = wddrives[lunit];
switch (cmd) {
case DIOCSBAD:
if ((flag & FWRITE) == 0)
error = EBADF;
else {
du->dk_bad = *(struct dkbad *)addr;
#ifdef TIHBAD144
bad144intern(du);
#endif
}
break;
case DIOCGDINFO:
*(struct disklabel *)addr = du->dk_dd;
break;
case DIOCGPART:
((struct partinfo *)addr)->disklab = &du->dk_dd;
((struct partinfo *)addr)->part =
&du->dk_dd.d_partitions[wdpart(dev)];
break;
case DIOCSDINFO:
if ((flag & FWRITE) == 0)
error = EBADF;
else
error = setdisklabel(&du->dk_dd, (struct disklabel *)addr,
/*(du->dk_flags&DKFL_BSDLABEL) ? du->dk_openpart : */0,
du->dk_dospartitions);
if (error == 0) {
du->dk_flags |= DKFL_BSDLABEL;
wdsetctlr(dev, du);
}
break;
case DIOCWLABEL:
du->dk_flags &= ~DKFL_WRITEPROT;
if ((flag & FWRITE) == 0)
error = EBADF;
else
du->dk_wlabel = *(int *)addr;
break;
case DIOCWDINFO:
du->dk_flags &= ~DKFL_WRITEPROT;
if ((flag & FWRITE) == 0)
error = EBADF;
else if ((error = setdisklabel(&du->dk_dd, (struct disklabel *)addr,
/*(du->dk_flags & DKFL_BSDLABEL) ? du->dk_openpart :*/ 0,
du->dk_dospartitions)) == 0) {
int wlab;
du->dk_flags |= DKFL_BSDLABEL;
wdsetctlr(dev, du);
/* simulate opening partition 0 so write succeeds */
du->dk_openpart |= (1 << 0); /* XXX */
wlab = du->dk_wlabel;
du->dk_wlabel = 1;
error = writedisklabel(dev, wdstrategy,
&du->dk_dd, du->dk_dospartitions);
du->dk_openpart = du->dk_copenpart | du->dk_bopenpart;
du->dk_wlabel = wlab;
}
break;
#ifdef notyet
case DIOCGDINFOP:
*(struct disklabel **)addr = &(du->dk_dd);
break;
case DIOCWFORMAT:
if ((flag & FWRITE) == 0)
error = EBADF;
else {
register struct format_op *fop;
fop = (struct format_op *)addr;
aiov.iov_base = fop->df_buf;
aiov.iov_len = fop->df_count;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_resid = fop->df_count;
auio.uio_segflg = 0;
auio.uio_offset = fop->df_startblk * du->dk_dd.d_secsize;
error = physio(wdformat, &rwdbuf[lunit], dev, B_WRITE,
minphys, &auio);
fop->df_count -= auio.uio_resid;
fop->df_reg[0] = du->dk_status;
fop->df_reg[1] = du->dk_error;
}
break;
#endif
default:
error = ENOTTY;
break;
}
return (error);
}
#ifdef B_FORMAT
int
wdformat(struct buf *bp)
{
bp->b_flags |= B_FORMAT;
return (wdstrategy(bp));
}
#endif
int
wdsize(dev_t dev)
{
int lunit = wdunit(dev), part = wdpart(dev);
struct disk *du;
if (lunit >= NWD)
return(-1);
if ((du = wddrives[lunit]) == 0)
return (-1);
if (du->dk_state < OPEN || (du->dk_flags & DKFL_BSDLABEL) == 0) {
int val;
val = wdopen(makewddev(major(dev), lunit, WDRAW), FREAD, S_IFBLK, 0);
if (val != 0)
return (-1);
}
if ((du->dk_flags & (DKFL_WRITEPROT|DKFL_BSDLABEL)) != DKFL_BSDLABEL)
return (-1);
else
return((int)du->dk_dd.d_partitions[part].p_size);
}
extern char *vmmap; /* poor name! */
/* dump core after a system crash */
int
wddump(dev_t dev)
{
register struct disk *du; /* disk unit to do the IO */
long num; /* number of sectors to write */
int ctrlr, lunit, part, wdc;
long blkoff, blknum;
long cylin, head, sector, stat;
long secpertrk, secpercyl, nblocks, i;
char *addr;
extern int Maxmem;
static wddoingadump = 0;
extern caddr_t CADDR1;
addr = (char *) 0; /* starting address */
/* toss any characters present prior to dump */
while (sgetc(1))
;
/* size of memory to dump */
num = Maxmem;
lunit = wdunit(dev); /* eventually support floppies? */
part = wdpart(dev); /* file system */
/* check for acceptable drive number */
if (lunit >= NWD)
return(ENXIO);
du = wddrives[lunit];
if (du == 0)
return(ENXIO);
/* was it ever initialized ? */
if (du->dk_state < OPEN)
return (ENXIO);
if (du->dk_flags & DKFL_WRITEPROT)
return(ENXIO);
wdc = du->dk_port;
ctrlr = du->dk_ctrlr;
/* Convert to disk sectors */
num = (u_long) num * NBPG / du->dk_dd.d_secsize;
/* check if controller active */
/*if (wdtab[ctrlr].b_active)
return(EFAULT); */
if (wddoingadump)
return(EFAULT);
secpertrk = du->dk_dd.d_nsectors;
secpercyl = du->dk_dd.d_secpercyl;
nblocks = du->dk_dd.d_partitions[part].p_size;
blkoff = du->dk_dd.d_partitions[part].p_offset;
/*pg("xunit %x, nblocks %d, dumplo %d num %d\n", part,nblocks,dumplo,num);*/
/* check transfer bounds against partition size */
if ((dumplo < 0) || ((dumplo + num) > nblocks))
return(EINVAL);
/* mark controller active for if we panic during the dump */
/* wdtab[ctrlr].b_active = 1; */
wddoingadump = 1;
i = 200000000;
while ((inb(wdc+wd_status) & WDCS_BUSY) && (i-- > 0))
;
outb(wdc+wd_sdh, WDSD_IBM | (du->dk_unit << 4));
outb(wdc+wd_command, WDCC_RESTORE | WD_STEP);
while (inb(wdc+wd_status) & WDCS_BUSY)
;
/* some compaq controllers require this ... */
wdsetctlr(dev, du);
blknum = dumplo + blkoff;
while (num > 0) {
pmap_enter(kernel_pmap, CADDR1, trunc_page(addr), VM_PROT_READ, TRUE);
/* compute disk address */
cylin = blknum / secpercyl;
head = (blknum % secpercyl) / secpertrk;
sector = blknum % secpertrk;
#ifdef TIHBAD144
if (du->dk_flags & DKFL_BADSECT) {
long newblk;
int i;
for (i = 0; du->dk_badsect[i] != -1; i++) {
if (blknum < du->dk_badsect[i]) {
break; /* sorted list, passed our block by */
} else if (blknum == du->dk_badsect[i]) {
newblk = du->dk_dd.d_secperunit -
du->dk_dd.d_nsectors - i - 1;
cylin = newblk / secpercyl;
head = (newblk % secpercyl) / secpertrk;
sector = newblk % secpertrk;
/* found and repl; done scanning bad144 table */
break;
}
}
}
#endif
sector++; /* origin 1 */
/* select drive. */
outb(wdc+wd_sdh, WDSD_IBM | (du->dk_unit<<4) | (head & 0xf));
while ((inb(wdc+wd_status) & WDCS_READY) == 0)
;
/* transfer some blocks */
outb(wdc+wd_sector, sector);
outb(wdc+wd_seccnt,1);
outb(wdc+wd_cyl_lo, cylin);
outb(wdc+wd_cyl_hi, cylin >> 8);
#ifdef notdef
/* lets just talk about this first...*/
pg ("sdh 0%o sector %d cyl %d addr 0x%x",
inb(wdc+wd_sdh), inb(wdc+wd_sector),
inb(wdc+wd_cyl_hi)*256+inb(wdc+wd_cyl_lo), addr);
#endif
outb(wdc+wd_command, WDCC_WRITE);
/* Ready to send data? */
while ((inb(wdc+wd_status) & WDCS_DRQ) == 0)
;
if (inb(wdc+wd_status) & WDCS_ERR)
return(EIO);
outsw (wdc+wd_data, CADDR1+((int)addr&(NBPG-1)), 256);
if (inb(wdc+wd_status) & WDCS_ERR)
return(EIO);
/* Check data request (should be done). */
if (inb(wdc+wd_status) & WDCS_DRQ)
return(EIO);
/* wait for completion */
for (i=200000000; inb(wdc+wd_status) & WDCS_BUSY ; i--) {
if (i < 0)
return (EIO);
}
/* error check the xfer */
if (inb(wdc+wd_status) & WDCS_ERR)
return(EIO);
if ((unsigned)addr % (1024*1024) == 0)
printf("%d ", num/2048);
/* update block count */
num--;
blknum++;
(int) addr += 512;
/* operator aborting dump? */
if (sgetc(1))
return(EINTR);
}
return(0);
}
#endif
#ifdef TIHBAD144
/*
* Internalize the bad sector table.
*/
void
bad144intern(struct disk *du)
{
int i;
if (du->dk_flags & DKFL_BADSECT) {
for (i = 0; i < 127; i++) {
du->dk_badsect[i] = -1;
}
for (i = 0; i < 126; i++) {
if (du->dk_bad.bt_bad[i].bt_cyl == 0xffff) {
break;
} else {
du->dk_badsect[i] =
du->dk_bad.bt_bad[i].bt_cyl * du->dk_dd.d_secpercyl +
(du->dk_bad.bt_bad[i].bt_trksec >> 8) * du->dk_dd.d_nsectors +
(du->dk_bad.bt_bad[i].bt_trksec & 0x00ff);
}
}
}
}
#endif
wdprint() {}
/* this routine was adopted from the kernel sources */
/* more efficient because b_cylin is not really as useful at this level */
/* so I eliminate the processing, I believe that sorting the sectors */
/* is adequate */
void
wddisksort(struct buf *dp, struct buf *bp)
{
register struct buf *ap;
/*
* If nothing on the activity queue, then
* we become the only thing.
*/
ap = dp->b_actf;
if(ap == NULL) {
dp->b_actf = bp;
dp->b_actl = bp;
bp->av_forw = NULL;
return;
}
while( ap->b_flags & B_XXX) {
if( ap->av_forw == 0 || (ap->av_forw->b_flags & B_XXX) == 0)
break;
ap = ap->av_forw;
}
/*
* If we lie after the first (currently active)
* request, then we must locate the second request list
* and add ourselves to it.
*/
if (bp->b_blkno < ap->b_blkno) {
while (ap->av_forw) {
/*
* Check for an ``inversion'' in the
* normally ascending cylinder numbers,
* indicating the start of the second request list.
*/
if (ap->av_forw->b_blkno < ap->b_blkno) {
/*
* Search the second request list
* for the first request at a larger
* cylinder number. We go before that;
* if there is no such request, we go at end.
*/
do {
if (bp->b_blkno < ap->av_forw->b_blkno)
goto insert;
ap = ap->av_forw;
} while (ap->av_forw);
goto insert; /* after last */
}
ap = ap->av_forw;
}
/*
* No inversions... we will go after the last, and
* be the first request in the second request list.
*/
goto insert;
}
/*
* Request is at/after the current request...
* sort in the first request list.
*/
while (ap->av_forw) {
/*
* We want to go after the current request
* if there is an inversion after it (i.e. it is
* the end of the first request list), or if
* the next request is a larger cylinder than our request.
*/
if (ap->av_forw->b_blkno < ap->b_blkno ||
bp->b_blkno < ap->av_forw->b_blkno )
goto insert;
ap = ap->av_forw;
}
/*
* Neither a second list nor a larger
* request... we go at the end of the first list,
* which is the same as the end of the whole schebang.
*/
insert:
bp->av_forw = ap->av_forw;
ap->av_forw = bp;
if (ap == dp->b_actl)
dp->b_actl = bp;
}
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