freebsd-dev/sys/dev/vinum/vinumrevive.c
Greg Lehey fe8b826551 revive_block:
Fix several instances of breakage in RAID-5 revive code.

   Tidy up code.

parityops:
   Don't attempt to do anything if the plex is degraded or worse.

parityrebuild:
   Add comments.
   Perform transfers in correct length.
2000-06-07 03:33:09 +00:00

632 lines
22 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.
*
* $Id: vinumrevive.c,v 1.10 2000/01/03 03:40:54 grog Exp grog $
* $FreeBSD$
*/
#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)
{
int s; /* priority level */
struct sd *sd;
struct plex *plex;
struct volume *vol;
struct buf *bp;
int error = EAGAIN;
int size; /* size of revive block, bytes */
daddr_t plexblkno; /* lblkno in plex */
int psd; /* parity subdisk number */
u_int64_t stripe; /* stripe number */
int paritysd = 0; /* set if this is the parity stripe */
struct rangelock *lock; /* for locking */
daddr_t stripeoffset; /* offset in stripe */
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) /* no block size */
||(sd->revive_blocksize & ((1 << DEV_BSHIFT) - 1))) { /* or invalid block size */
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;
} else if (sd->revive_blocksize > MAX_REVIVE_BLOCKSIZE)
sd->revive_blocksize = MAX_REVIVE_BLOCKSIZE;
size = min(sd->revive_blocksize >> DEV_BSHIFT, sd->sectors - sd->revived) << DEV_BSHIFT;
sd->reviver = curproc->p_pid; /* note who last had a bash at it */
/* Now decide where to read from */
switch (plex->organization) {
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 */
break;
case plex_raid4:
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 */
+stripeoffset; /* offset from beginning of stripe */
stripe = (sd->revived / plex->stripesize); /* stripe number */
/* Make sure we don't go beyond the end of the band. */
size = min(size, (plex->stripesize - stripeoffset) << DEV_BSHIFT);
if (plex->organization == plex_raid4)
psd = plex->subdisks - 1; /* parity subdisk for this stripe */
else
psd = plex->subdisks - 1 - stripe % plex->subdisks; /* parity subdisk for this stripe */
paritysd = plex->sdnos[psd] == sdno; /* note if it's the parity subdisk */
/*
* Now adjust for the strangenesses
* in RAID-4 and RAID-5 striping.
*/
if (sd->plexsdno > psd) /* beyond the parity stripe, */
plexblkno -= plex->stripesize; /* one stripe less */
else if (paritysd)
plexblkno -= plex->stripesize * sd->plexsdno; /* go back to the beginning of the band */
break;
case plex_disorg: /* to keep the compiler happy */
}
if (paritysd) { /* we're reviving a parity block, */
bp = parityrebuild(plex, sd->revived, size, rebuildparity, &lock, NULL); /* do the grunt work */
if (bp == NULL) /* no buffer space */
return ENOMEM; /* chicken out */
} else { /* data block */
s = splbio();
bp = geteblk(size); /* Get a buffer */
splx(s);
if (bp == NULL)
return ENOMEM;
/*
* Amount to transfer: block size, unless it
* would overlap the end.
*/
bp->b_bcount = size;
bp->b_resid = bp->b_bcount;
bp->b_blkno = plexblkno; /* start here */
if (isstriped(plex)) /* we need to lock striped plexes */
lock = lockrange(plexblkno << DEV_BSHIFT, bp, plex); /* lock it */
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 = VINUMDEV(plex->volno, 0, 0, VINUM_VOLUME_TYPE); /* create the device number */
else /* it's an unattached plex */
bp->b_dev = VINUM_PLEX(sd->plexno); /* create the device number */
bp->b_iocmd = BIO_READ; /* either way, read it */
bp->b_flags = 0;
vinumstart(bp, 1);
bufwait(bp);
}
if (bp->b_ioflags & BIO_ERROR)
error = bp->b_error;
else
/* Now write to the subdisk */
{
bp->b_dev = VINUM_SD(sdno); /* create the device number */
bp->b_flags &= ~B_DONE; /* no longer done */
bp->b_ioflags = BIO_ORDERED; /* and make this an ordered write */
bp->b_iocmd = BIO_WRITE;
BUF_LOCKINIT(bp); /* get a lock for the buffer */
BUF_LOCK(bp, LK_EXCLUSIVE); /* and lock it */
bp->b_resid = bp->b_bcount;
bp->b_blkno = sd->revived; /* write it to here */
sdio(bp); /* perform the I/O */
bufwait(bp);
if (bp->b_ioflags & BIO_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: %p\n%s dev %d.%d, offset 0x%x, length %ld\n",
rq->sdno,
rq,
rq->bp->b_iocmd == BIO_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, */
bp->b_flags |= B_INVAL;
bp->b_ioflags &= ~BIO_ERROR;
brelse(bp); /* is this kosher? */
}
return error;
}
/*
* Check or rebuild the parity blocks of a RAID-4
* or RAID-5 plex.
*
* The variables plex->checkblock and
* plex->rebuildblock represent the
* subdisk-relative address of the stripe we're
* looking at, not the plex-relative address. We
* store it in the plex and not as a local
* variable because this function could be
* stopped, and we don't want to repeat the part
* we've already done. This is also the reason
* why we don't initialize it here except at the
* end. It gets initialized with the plex on
* creation.
*
* Each call to this function processes at most
* one stripe. We can't loop in this function,
* because we're unstoppable, so we have to be
* called repeatedly from userland.
*/
void
parityops(struct vinum_ioctl_msg *data)
{
int plexno;
struct plex *plex;
int size; /* I/O transfer size, bytes */
int stripe; /* stripe number in plex */
int psd; /* parity subdisk number */
struct rangelock *lock; /* lock on stripe */
struct _ioctl_reply *reply;
off_t pstripe; /* pointer to our stripe counter */
struct buf *pbp;
off_t errorloc; /* offset of parity error */
enum parityop op; /* operation to perform */
plexno = data->index;
op = data->op;
pbp = NULL;
reply = (struct _ioctl_reply *) data;
reply->error = EAGAIN; /* expect to repeat this call */
plex = &PLEX[plexno];
if (!isparity(plex)) { /* not RAID-4 or RAID-5 */
reply->error = EINVAL;
return;
} else if (plex->state < plex_flaky) {
reply->error = EIO;
strcpy(reply->msg, "Plex is not completely accessible\n");
return;
}
pstripe = data->offset;
stripe = pstripe / plex->stripesize; /* stripe number */
psd = plex->subdisks - 1 - stripe % plex->subdisks; /* parity subdisk for this stripe */
size = min(DEFAULT_REVIVE_BLOCKSIZE, /* one block at a time */
plex->stripesize << DEV_BSHIFT);
pbp = parityrebuild(plex, pstripe, size, op, &lock, &errorloc); /* do the grunt work */
if (pbp == NULL) { /* no buffer space */
reply->error = ENOMEM;
return; /* chicken out */
}
/*
* Now we have a result in the data buffer of
* the parity buffer header, which we have kept.
* Decide what to do with it.
*/
reply->msg[0] = '\0'; /* until shown otherwise */
if ((pbp->b_ioflags & BIO_ERROR) == 0) { /* no error */
if ((op == rebuildparity)
|| (op == rebuildandcheckparity)) {
pbp->b_iocmd = BIO_WRITE;
pbp->b_resid = pbp->b_bcount;
BUF_LOCKINIT(pbp); /* get a lock for the buffer */
BUF_LOCK(pbp, LK_EXCLUSIVE); /* and lock it */
sdio(pbp); /* write the parity block */
bufwait(pbp);
}
if (((op == checkparity)
|| (op == rebuildandcheckparity))
&& (errorloc != -1)) {
if (op == checkparity)
reply->error = EIO;
sprintf(reply->msg,
"Parity incorrect at offset 0x%llx\n",
errorloc);
}
if (reply->error == EAGAIN) { /* still OK, */
plex->checkblock = pstripe + (pbp->b_bcount >> DEV_BSHIFT); /* moved this much further down */
if (plex->checkblock >= SD[plex->sdnos[0]].sectors) { /* finished */
plex->checkblock = 0;
reply->error = 0;
}
}
}
if (pbp->b_ioflags & BIO_ERROR)
reply->error = pbp->b_error;
pbp->b_flags |= B_INVAL;
pbp->b_ioflags &= ~BIO_ERROR;
brelse(pbp);
unlockrange(plexno, lock);
}
/*
* Rebuild a parity stripe. Return pointer to
* parity bp. On return,
*
* 1. The band is locked. The caller must unlock
* the band and release the buffer header.
*
* 2. All buffer headers except php have been
* released. The caller must release pbp.
*
* 3. For checkparity and rebuildandcheckparity,
* the parity is compared with the current
* parity block. If it's different, the
* offset of the error is returned to
* errorloc. The caller can set the value of
* the pointer to NULL if this is called for
* rebuilding parity.
*
* pstripe is the subdisk-relative base address of
* the data to be reconstructed, size is the size
* of the transfer in bytes.
*/
struct buf *
parityrebuild(struct plex *plex,
u_int64_t pstripe,
int size,
enum parityop op,
struct rangelock **lockp,
off_t * errorloc)
{
int error;
int s;
int sdno;
u_int64_t stripe; /* stripe number */
int *parity_buf; /* buffer address for current parity block */
int *newparity_buf; /* and for new parity block */
int mysize; /* I/O transfer size for this transfer */
int isize; /* mysize in ints */
int i;
int psd; /* parity subdisk number */
int newpsd; /* and "subdisk number" of new parity */
struct buf **bpp; /* pointers to our bps */
struct buf *pbp; /* buffer header for parity stripe */
int *sbuf;
int bufcount; /* number of buffers we need */
stripe = pstripe / plex->stripesize; /* stripe number */
psd = plex->subdisks - 1 - stripe % plex->subdisks; /* parity subdisk for this stripe */
parity_buf = NULL; /* to keep the compiler happy */
error = 0;
/*
* It's possible that the default transfer size
* we chose is not a factor of the stripe size.
* We *must* limit this operation to a single
* stripe, at least for RAID-5 rebuild, since
* the parity subdisk changes between stripes,
* so in this case we need to perform a short
* transfer. Set variable mysize to reflect
* this.
*/
mysize = min(size, (plex->stripesize * (stripe + 1) - pstripe) << DEV_BSHIFT);
isize = mysize / (sizeof(int)); /* number of ints in the buffer */
bufcount = plex->subdisks + 1; /* sd buffers plus result buffer */
newpsd = plex->subdisks;
bpp = (struct buf **) Malloc(bufcount * sizeof(struct buf *)); /* array of pointers to bps */
/* First, build requests for all subdisks */
for (sdno = 0; sdno < bufcount; sdno++) { /* for each subdisk */
if ((sdno != psd) || (op != rebuildparity)) {
/* Get a buffer header and initialize it. */
s = splbio();
bpp[sdno] = geteblk(mysize); /* Get a buffer */
if (bpp[sdno] == NULL) {
while (sdno-- > 0) { /* release the ones we got */
bpp[sdno]->b_flags |= B_INVAL;
brelse(bpp[sdno]); /* give back our resources */
}
splx(s);
printf("vinum: can't allocate buffer space for parity op.\n");
return NULL; /* no bpps */
}
splx(s);
if (sdno == psd)
parity_buf = (int *) bpp[sdno]->b_data;
if (sdno == newpsd) /* the new one? */
bpp[sdno]->b_dev = VINUM_SD(plex->sdnos[psd]); /* write back to the parity SD */
else
bpp[sdno]->b_dev = VINUM_SD(plex->sdnos[sdno]); /* device number */
bpp[sdno]->b_iocmd = BIO_READ; /* either way, read it */
bpp[sdno]->b_flags = 0;
bpp[sdno]->b_bcount = mysize;
bpp[sdno]->b_resid = bpp[sdno]->b_bcount;
bpp[sdno]->b_blkno = pstripe; /* transfer from here */
}
}
/* Initialize result buffer */
pbp = bpp[newpsd];
newparity_buf = (int *) bpp[newpsd]->b_data;
bzero(newparity_buf, mysize);
/*
* Now lock the stripe with the first non-parity
* bp as locking bp.
*/
*lockp = lockrange(pstripe * plex->stripesize * (plex->subdisks - 1),
bpp[psd ? 0 : 1],
plex);
/*
* Then issue requests for all subdisks in
* parallel. Don't transfer the parity stripe
* if we're rebuilding parity, unless we also
* want to check it.
*/
for (sdno = 0; sdno < plex->subdisks; sdno++) { /* for each real subdisk */
if ((sdno != psd) || (op != rebuildparity)) {
BUF_LOCKINIT(bpp[sdno]); /* get a lock for the buffer */
BUF_LOCK(bpp[sdno], LK_EXCLUSIVE); /* and lock it */
sdio(bpp[sdno]);
}
}
/*
* Next, wait for the requests to complete.
* We wait in the order in which they were
* issued, which isn't necessarily the order in
* which they complete, but we don't have a
* convenient way of doing the latter, and the
* delay is minimal.
*/
for (sdno = 0; sdno < plex->subdisks; sdno++) { /* for each subdisk */
if ((sdno != psd) || (op != rebuildparity)) {
bufwait(bpp[sdno]);
if (bpp[sdno]->b_ioflags & BIO_ERROR) /* can't read, */
error = bpp[sdno]->b_error;
else if (sdno != psd) { /* update parity */
sbuf = (int *) bpp[sdno]->b_data;
for (i = 0; i < isize; i++)
((int *) newparity_buf)[i] ^= sbuf[i]; /* xor in the buffer */
}
}
if (sdno != psd) { /* release all bps except parity */
bpp[sdno]->b_flags |= B_INVAL;
brelse(bpp[sdno]); /* give back our resources */
}
}
/*
* If we're checking, compare the calculated
* and the read parity block. If they're
* different, return the plex-relative offset;
* otherwise return -1.
*/
if ((op == checkparity)
|| (op == rebuildandcheckparity)) {
*errorloc = -1; /* no error yet */
for (i = 0; i < isize; i++) {
if (parity_buf[i] != newparity_buf[i]) {
*errorloc = (u_long) (pstripe << DEV_BSHIFT) * (plex->subdisks - 1)
+ i * sizeof(int);
break;
}
}
bpp[psd]->b_flags |= B_INVAL;
brelse(bpp[psd]); /* give back our resources */
}
/* release our resources */
Free(bpp);
if (error) {
pbp->b_ioflags |= BIO_ERROR;
pbp->b_error = error;
}
return pbp;
}
/*
* Initialize a subdisk by writing zeroes to the
* complete address space. If verify is set,
* check each transfer for correctness.
*
* Each call to this function writes (and maybe
* checks) a single block.
*/
int
initsd(int sdno, int verify)
{
int s; /* priority level */
struct sd *sd;
struct plex *plex;
struct volume *vol;
struct buf *bp;
int error;
int size; /* size of init block, bytes */
daddr_t plexblkno; /* lblkno in plex */
int verified; /* set when we're happy with what we wrote */
error = 0;
plexblkno = 0; /* to keep the compiler happy */
sd = &SD[sdno];
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->init_blocksize == 0) {
if (plex->stripesize != 0) /* we're striped, don't init more than */
sd->init_blocksize = min(DEFAULT_REVIVE_BLOCKSIZE, /* one block at a time */
plex->stripesize << DEV_BSHIFT);
else
sd->init_blocksize = DEFAULT_REVIVE_BLOCKSIZE;
} else if (sd->init_blocksize > MAX_REVIVE_BLOCKSIZE)
sd->init_blocksize = MAX_REVIVE_BLOCKSIZE;
size = min(sd->init_blocksize >> DEV_BSHIFT, sd->sectors - sd->initialized) << DEV_BSHIFT;
verified = 0;
while (!verified) { /* until we're happy with it, */
s = splbio();
bp = geteblk(size); /* Get a buffer */
splx(s);
if (bp == NULL)
return ENOMEM;
bp->b_bcount = size;
bp->b_resid = bp->b_bcount;
bp->b_blkno = sd->initialized; /* write it to here */
bzero(bp->b_data, bp->b_bcount);
bp->b_dev = VINUM_SD(sdno); /* create the device number */
BUF_LOCKINIT(bp); /* get a lock for the buffer */
BUF_LOCK(bp, LK_EXCLUSIVE); /* and lock it */
bp->b_iocmd = BIO_WRITE;
sdio(bp); /* perform the I/O */
bufwait(bp);
if (bp->b_ioflags & BIO_ERROR)
error = bp->b_error;
if (bp->b_qindex == 0) { /* not on a queue, */
bp->b_flags |= B_INVAL;
bp->b_ioflags &= ~BIO_ERROR;
brelse(bp); /* is this kosher? */
}
if ((error == 0) && verify) { /* check that it got there */
s = splbio();
bp = geteblk(size); /* get a buffer */
if (bp == NULL) {
splx(s);
error = ENOMEM;
} else {
bp->b_bcount = size;
bp->b_resid = bp->b_bcount;
bp->b_blkno = sd->initialized; /* read from here */
bp->b_dev = VINUM_SD(sdno); /* create the device number */
bp->b_iocmd = BIO_READ; /* read it back */
splx(s);
BUF_LOCKINIT(bp); /* get a lock for the buffer */
BUF_LOCK(bp, LK_EXCLUSIVE); /* and lock it */
sdio(bp);
bufwait(bp);
/*
* XXX Bug fix code. This is hopefully no
* longer needed (21 February 2000).
*/
if (bp->b_ioflags & BIO_ERROR)
error = bp->b_error;
else if ((*bp->b_data != 0) /* first word spammed */
||(bcmp(bp->b_data, &bp->b_data[1], bp->b_bcount - 1))) { /* or one of the others */
printf("vinum: init error on %s, offset 0x%llx sectors\n",
sd->name,
(long long) sd->initialized);
verified = 0;
} else
verified = 1;
if (bp->b_qindex == 0) { /* not on a queue, */
bp->b_flags |= B_INVAL;
bp->b_ioflags &= ~BIO_ERROR;
brelse(bp); /* is this kosher? */
}
}
} else
verified = 1;
}
if (error == 0) { /* did it, */
sd->initialized += size >> DEV_BSHIFT; /* moved this much further down */
if (sd->initialized >= sd->sectors) { /* finished */
sd->initialized = 0;
set_sd_state(sdno, sd_initialized, 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 */
} else /* more to go, */
error = EAGAIN; /* ya'll come back, see? */
}
return error;
}
/* Local Variables: */
/* fill-column: 50 */
/* End: */