freebsd-dev/sys/dev/vinum/vinumrevive.c
1999-08-28 01:08:13 +00:00

282 lines
10 KiB
C

/*-
* Copyright (c) 1997, 1998, 1999
* Nan Yang Computer Services Limited. All rights reserved.
*
* Parts copyright (c) 1997, 1998 Cybernet Corporation, NetMAX project.
*
* Written by Greg Lehey
*
* This software is distributed under the so-called ``Berkeley
* License'':
*
* 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 Nan Yang Computer
* Services Limited.
* 4. Neither the name of the Company 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 ``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 company 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.
*
* $FreeBSD$
*/
#include <dev/vinum/vinumhdr.h>
#include <dev/vinum/request.h>
/*
* Revive a block of a subdisk. Return an error
* indication. EAGAIN means successful copy, but
* that more blocks remain to be copied. EINVAL
* means that the subdisk isn't associated with a
* plex (which means a programming error if we get
* here at all; FIXME).
*/
int
revive_block(int sdno)
{
struct sd *sd;
struct plex *plex;
struct volume *vol;
struct buf *bp;
int error = EAGAIN;
int size; /* size of revive block, bytes */
int s; /* priority level */
daddr_t plexblkno; /* lblkno in plex */
int psd; /* parity subdisk number */
int stripe; /* stripe number */
int isparity = 0; /* set if this is the parity stripe */
struct rangelock *lock; /* for locking */
plexblkno = 0; /* to keep the compiler happy */
sd = &SD[sdno];
lock = NULL;
if (sd->plexno < 0) /* no plex? */
return EINVAL;
plex = &PLEX[sd->plexno]; /* point to plex */
if (plex->volno >= 0)
vol = &VOL[plex->volno];
else
vol = NULL;
if (sd->revive_blocksize == 0) {
if (plex->stripesize != 0) /* we're striped, don't revive more than */
sd->revive_blocksize = min(DEFAULT_REVIVE_BLOCKSIZE, /* one block at a time */
plex->stripesize << DEV_BSHIFT);
else
sd->revive_blocksize = DEFAULT_REVIVE_BLOCKSIZE;
}
size = min(sd->revive_blocksize >> DEV_BSHIFT, sd->sectors - sd->revived) << DEV_BSHIFT;
s = splbio();
bp = geteblk(size); /* Get a buffer */
if (bp == NULL) {
splx(s);
return ENOMEM;
}
if (bp->b_qindex != 0) /* on a queue, */
bremfree(bp); /* remove it XXX how can this happen? */
splx(s);
/*
* Amount to transfer: block size, unless it
* would overlap the end
*/
bp->b_bufsize = size;
bp->b_bcount = bp->b_bufsize;
bp->b_resid = 0;
/* Now decide where to read from */
switch (plex->organization) {
daddr_t stripeoffset; /* offset in stripe */
case plex_concat:
plexblkno = sd->revived + sd->plexoffset; /* corresponding address in plex */
break;
case plex_striped:
stripeoffset = sd->revived % plex->stripesize; /* offset from beginning of stripe */
plexblkno = sd->plexoffset /* base */
+ (sd->revived - stripeoffset) * plex->subdisks /* offset to beginning of stripe */
+ sd->revived % plex->stripesize; /* offset from beginning of stripe */
lock = lockrange(plexblkno << DEV_BSHIFT, bp, plex); /* lock it */
break;
case plex_raid5:
stripeoffset = sd->revived % plex->stripesize; /* offset from beginning of stripe */
plexblkno = sd->plexoffset /* base */
+ (sd->revived - stripeoffset) * (plex->subdisks - 1) /* offset to beginning of stripe */
+sd->revived % plex->stripesize; /* offset from beginning of stripe */
stripe = (sd->revived / plex->stripesize); /* stripe number */
psd = plex->subdisks - 1 - stripe % plex->subdisks; /* parity subdisk for this stripe */
isparity = plex->sdnos[psd] == sdno; /* note if it's the parity subdisk */
/*
* Now adjust for the strangenesses
* in RAID-5 striping.
*/
if (sd->plexsdno > psd) /* beyond the parity stripe, */
plexblkno -= plex->stripesize; /* one stripe less */
lock = lockrange(plexblkno << DEV_BSHIFT, bp, plex); /* lock it */
break;
case plex_disorg: /* to keep the compiler happy */
}
if (isparity) { /* we're reviving a parity block, */
int mysdno;
int *tbuf; /* temporary buffer to read the stuff in to */
caddr_t parity_buf; /* the address supplied by geteblk */
int isize;
int i;
tbuf = (int *) Malloc(size);
isize = size / (sizeof(int)); /* number of ints in the buffer */
/*
* We have calculated plexblkno assuming it
* was a data block. Go back to the beginning
* of the band.
*/
plexblkno -= plex->stripesize * sd->plexsdno;
/*
* Read each subdisk in turn, except for this
* one, and xor them together.
*/
parity_buf = bp->b_data; /* save the buffer getblk gave us */
bzero(parity_buf, size); /* start with nothing */
bp->b_data = (caddr_t) tbuf; /* read into here */
for (mysdno = 0; mysdno < plex->subdisks; mysdno++) { /* for each subdisk */
if (mysdno != sdno) { /* not our subdisk */
if (vol != NULL) /* it's part of a volume, */
/*
* First, read the data from the volume.
* We don't care which plex, that's the
* driver's job.
*/
bp->b_dev = VINUMBDEV(plex->volno, 0, 0, VINUM_VOLUME_TYPE); /* create the device number */
else /* it's an unattached plex */
bp->b_dev = VINUMRBDEV(sd->plexno, VINUM_RAWPLEX_TYPE); /* create the device number */
bp->b_blkno = plexblkno; /* read from here */
bp->b_flags = B_READ; /* either way, read it */
BUF_LOCKINIT(bp); /* get a lock for the buffer */
BUF_LOCK(bp, LK_EXCLUSIVE); /* and lock it */
vinumstart(bp, 1);
biowait(bp);
if (bp->b_flags & B_ERROR) /* can't read, */
/*
* If we have a read error, there's
* nothing we can do. By this time, the
* daemon has already run out of magic.
*/
break;
/*
* To save time, we do the XOR wordwise.
* This requires sectors to be a multiple
* of the length of an int, which is
* currently always the case.
*/
for (i = 0; i < isize; i++)
((int *) parity_buf)[i] ^= tbuf[i]; /* xor in the buffer */
plexblkno += plex->stripesize; /* move on to the next subdisk */
}
}
bp->b_data = parity_buf; /* put the buf header back the way it was */
Free(tbuf);
} else {
bp->b_blkno = plexblkno; /* start here */
if (vol != NULL) /* it's part of a volume, */
/*
* First, read the data from the volume. We
* don't care which plex, that's bre's job.
*/
bp->b_dev = VINUMBDEV(plex->volno, 0, 0, VINUM_VOLUME_TYPE); /* create the device number */
else /* it's an unattached plex */
bp->b_dev = VINUMRBDEV(sd->plexno, VINUM_RAWPLEX_TYPE); /* create the device number */
bp->b_flags = B_READ; /* either way, read it */
vinumstart(bp, 1);
biowait(bp);
}
if (bp->b_flags & B_ERROR)
error = bp->b_error;
else
/* Now write to the subdisk */
{
s = splbio();
if (bp->b_qindex != 0) /* on a queue, */
bremfree(bp); /* remove it */
splx(s);
bp->b_dev = VINUMRBDEV(sdno, VINUM_RAWSD_TYPE); /* create the device number */
bp->b_flags = B_ORDERED; /* and make this an ordered write */
BUF_LOCKINIT(bp); /* get a lock for the buffer */
BUF_LOCK(bp, LK_EXCLUSIVE); /* and lock it */
bp->b_resid = 0x0;
bp->b_blkno = sd->revived; /* write it to here */
sdio(bp); /* perform the I/O */
biowait(bp);
if (bp->b_flags & B_ERROR)
error = bp->b_error;
else {
sd->revived += bp->b_bcount >> DEV_BSHIFT; /* moved this much further down */
if (sd->revived >= sd->sectors) { /* finished */
sd->revived = 0;
set_sd_state(sdno, sd_up, setstate_force); /* bring the sd up */
log(LOG_INFO, "vinum: %s is %s\n", sd->name, sd_state(sd->state));
save_config(); /* and save the updated configuration */
error = 0; /* we're done */
}
}
if (lock) /* we took a lock, */
unlockrange(sd->plexno, lock); /* give it back */
while (sd->waitlist) { /* we have waiting requests */
#if VINUMDEBUG
struct request *rq = sd->waitlist;
if (debug & DEBUG_REVIVECONFLICT)
log(LOG_DEBUG,
"Relaunch revive conflict sd %d: %x\n%s dev %d.%d, offset 0x%x, length %ld\n",
rq->sdno,
(u_int) rq,
rq->bp->b_flags & B_READ ? "Read" : "Write",
major(rq->bp->b_dev),
minor(rq->bp->b_dev),
rq->bp->b_blkno,
rq->bp->b_bcount);
#endif
launch_requests(sd->waitlist, 1); /* do them now */
sd->waitlist = sd->waitlist->next; /* and move on to the next */
}
}
if (bp->b_qindex == 0) /* not on a queue, */
brelse(bp); /* is this kosher? */
return error;
}
/* Local Variables: */
/* fill-column: 50 */
/* End: */