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Diffstat (limited to 'sys/dev/vinum/vinumrequest.c')
| -rw-r--r-- | sys/dev/vinum/vinumrequest.c | 966 |
1 files changed, 966 insertions, 0 deletions
diff --git a/sys/dev/vinum/vinumrequest.c b/sys/dev/vinum/vinumrequest.c new file mode 100644 index 0000000..79c5253 --- /dev/null +++ b/sys/dev/vinum/vinumrequest.c @@ -0,0 +1,966 @@ +/* XXX to do: + + * Decide where we need splbio () + */ +/*- + * Copyright (c) 1997, 1998 + * Nan Yang Computer Services Limited. All rights reserved. + * + * 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: request.c,v 1.3 1998/11/02 04:09:34 grog Exp $ + */ + +#define REALLYKERNEL +#include "vinumhdr.h" +#include "request.h" +#include <miscfs/specfs/specdev.h> +#include <sys/resourcevar.h> + +/* pointer to ioctl p parameter, to save passing it around */ +extern struct proc *myproc; + +enum requeststatus bre(struct request *rq, + int plexno, + daddr_t * diskstart, + daddr_t diskend); +enum requeststatus bre5(struct request *rq, + int plexno, + daddr_t * diskstart, + daddr_t diskend); +enum requeststatus build_read_request(struct request *rq, int volplexno); +enum requeststatus build_write_request(struct request *rq); +enum requeststatus build_rq_buffer(struct rqelement *rqe, struct plex *plex); +void freerq(struct request *rq); +void free_rqg(struct rqgroup *rqg); +int find_alternate_sd(struct request *rq); +int check_range_covered(struct request *); +void complete_rqe(struct buf *bp); +void complete_raid5_write(struct rqelement *); +int abortrequest(struct request *rq, int error); +void sdio(struct buf *bp); +void sdio_done(struct buf *bp); +int vinum_bounds_check(struct buf *bp, struct volume *vol); +caddr_t allocdatabuf(struct rqelement *rqe); +void freedatabuf(struct rqelement *rqe); + +#ifdef DEBUG +struct rqinfo rqinfo[RQINFO_SIZE]; +struct rqinfo *rqip = rqinfo; + +void +logrq(enum rqinfo_type type, union rqinfou info, struct buf *ubp) +{ + BROKEN_GDB; + int s = splhigh(); + + vinum_conf.rqipp = &rqip; /* XXX for broken gdb */ + vinum_conf.rqinfop = rqinfo; /* XXX for broken gdb */ + +#if __FreeBSD__ < 3 + rqip->timestamp = time; /* when did this happen? */ +#else + microtime(&rqip->timestamp); /* when did this happen? */ +#endif + rqip->type = type; + rqip->bp = ubp; /* user buffer */ + switch (type) { + case loginfo_user_bp: + case loginfo_user_bpl: + bcopy(info.bp, &rqip->info.b, sizeof(struct buf)); + break; + + case loginfo_iodone: + case loginfo_rqe: + case loginfo_raid5_data: + case loginfo_raid5_parity: + bcopy(info.rqe, &rqip->info.rqe, sizeof(struct rqelement)); + break; + + case loginfo_unused: + break; + } + rqip++; + if (rqip >= &rqinfo[RQINFO_SIZE]) /* wrap around */ + rqip = rqinfo; + splx(s); +} + +#endif + +void +vinumstrategy(struct buf *bp) +{ + BROKEN_GDB; + int volno; + struct volume *vol = NULL; + int s; + struct devcode *device = (struct devcode *) &bp->b_dev; /* decode device number */ + enum requeststatus status; + + /* We may have changed the configuration in + * an interrupt context. Update it now. It + * could change again, so do it in a loop. + * XXX this is broken and contains a race condition. + * The correct way is to hand it off the the Vinum + * daemon, but I haven't found a name for it yet */ + while (vinum_conf.flags & VF_DIRTYCONFIG) { /* config is dirty, save it now */ + int driveno; + + vinum_conf.flags &= ~VF_DIRTYCONFIG; /* turn it off */ + for (driveno = 0; driveno < vinum_conf.drives_used; driveno++) { + if ((DRIVE[driveno].state == drive_down) /* drive down */ + &&(DRIVE[driveno].vp != NULL)) /* but still open */ + close_drive(&DRIVE[driveno]); /* close it now */ + } + save_config(); + } + + switch (device->type) { + case VINUM_SD_TYPE: + sdio(bp); + return; + + /* In fact, vinum doesn't handle drives: they're + * handled directly by the disk drivers */ + case VINUM_DRIVE_TYPE: + default: + bp->b_error = EIO; /* I/O error */ + bp->b_flags |= B_ERROR; + biodone(bp); + return; + + case VINUM_VOLUME_TYPE: /* volume I/O */ + volno = VOLNO(bp->b_dev); + vol = &VOL[volno]; + if (vol->state != volume_up) { /* can't access this volume */ + bp->b_error = EIO; /* I/O error */ + bp->b_flags |= B_ERROR; + biodone(bp); + return; + } + if (vinum_bounds_check(bp, vol) <= 0) { /* don't like them bounds */ + biodone(bp); /* have nothing to do with this */ + return; + } + /* FALLTHROUGH */ + /* Plex I/O is pretty much the same as volume I/O + * for a single plex. Indicate this by passing a NULL + * pointer (set above) for the volume */ + case VINUM_PLEX_TYPE: + bp->b_resid = bp->b_bcount; /* transfer everything */ + vinumstart(bp, 0); + return; + } +} + +/* Start a transfer. Return -1 on error, + * 0 if OK, 1 if we need to retry. + * Parameter reviveok is set when doing + * transfers for revives: it allows transfers to + * be started immediately when a revive is in + * progress. During revive, normal transfers + * are queued if they share address space with + * a currently active revive operation. */ +int +vinumstart(struct buf *bp, int reviveok) +{ + BROKEN_GDB; + int plexno; + int maxplex; /* maximum number of plexes to handle */ + struct volume *vol; + struct rqgroup *rqg; /* current plex's requests */ + struct rqelement *rqe; /* individual element */ + struct request *rq; /* build up our request here */ + int rqno; /* index in request list */ + enum requeststatus status; + +#if DEBUG + if (debug & DEBUG_LASTREQS) + logrq(loginfo_user_bp, bp, bp); +#endif + + /* XXX In these routines, we're assuming that + * we will always be called with bp->b_bcount + * which is a multiple of the sector size. This + * is a reasonable assumption, since we are only + * called from system routines. Should we check + * anyway? */ + + if ((bp->b_bcount % DEV_BSIZE) != 0) { /* bad length */ + bp->b_error = EINVAL; /* invalid size */ + bp->b_flags |= B_ERROR; + biodone(bp); + return -1; + } + rq = (struct request *) Malloc(sizeof(struct request)); /* allocate a request struct */ + if (rq == NULL) { /* can't do it */ + bp->b_error = ENOMEM; /* can't get memory */ + bp->b_flags |= B_ERROR; + biodone(bp); + return -1; + } + bzero(rq, sizeof(struct request)); + + /* Note the volume ID. This can be NULL, which + * the request building functions use as an + * indication for single plex I/O */ + rq->bp = bp; /* and the user buffer struct */ + + if (DEVTYPE(bp->b_dev) == VINUM_VOLUME_TYPE) { /* it's a volume, */ + rq->volplex.volno = VOLNO(bp->b_dev); /* get the volume number */ + vol = &VOL[rq->volplex.volno]; /* and point to it */ + vol->active++; /* one more active request */ + maxplex = vol->plexes; /* consider all its plexes */ + } else { + vol = NULL; /* no volume */ + rq->volplex.plexno = PLEXNO(bp->b_dev); /* point to the plex */ + rq->isplex = 1; /* note that it's a plex */ + maxplex = 1; /* just the one plex */ + } + + if (bp->b_flags & B_READ) { + /* This is a read request. Decide + * which plex to read from. + * + * There's a potential race condition here, + * since we're not locked, and we could end + * up multiply incrementing the round-robin + * counter. This doesn't have any serious + * effects, however. */ + if (vol != NULL) { + vol->reads++; + vol->bytes_read += bp->b_bcount; + plexno = vol->preferred_plex; /* get the plex to use */ + if (plexno < 0) { /* round robin */ + plexno = vol->last_plex_read; + vol->last_plex_read++; + if (vol->last_plex_read == vol->plexes) /* got the the end? */ + vol->last_plex_read = 0; /* wrap around */ + } + status = build_read_request(rq, plexno); /* build a request */ + } else { + daddr_t diskaddr = bp->b_blkno; /* start offset of transfer */ + status = bre(rq, /* build a request list */ + rq->volplex.plexno, + &diskaddr, + diskaddr + (bp->b_bcount / DEV_BSIZE)); + } + + if ((status > REQUEST_RECOVERED) /* can't satisfy it */ + ||(bp->b_flags & B_DONE)) { /* XXX shouldn't get this without bad status */ + if (status == REQUEST_DOWN) { /* not enough subdisks */ + bp->b_error = EIO; /* I/O error */ + bp->b_flags |= B_ERROR; + } + biodone(bp); + freerq(rq); + return -1; + } { /* XXX */ + int result; + int s = splhigh(); + result = launch_requests(rq, reviveok); /* now start the requests if we can */ + splx(s); + return result; + } + } else + /* This is a write operation. We write to all + * plexes. If this is a RAID 5 plex, we must also + * update the parity stripe. */ + { + if (vol != NULL) { + vol->writes++; + vol->bytes_written += bp->b_bcount; + status = build_write_request(rq); /* Not all the subdisks are up */ + } else { /* plex I/O */ + daddr_t diskstart; + + diskstart = bp->b_blkno; /* start offset of transfer */ + status = bre(rq, + PLEXNO(bp->b_dev), + &diskstart, + bp->b_blkno + (bp->b_bcount / DEV_BSIZE)); /* build requests for the plex */ + } + if ((status > REQUEST_RECOVERED) /* can't satisfy it */ + ||(bp->b_flags & B_DONE)) { /* XXX shouldn't get this without bad status */ + if (status == REQUEST_DOWN) { /* not enough subdisks */ + bp->b_error = EIO; /* I/O error */ + bp->b_flags |= B_ERROR; + } + if ((bp->b_flags & B_DONE) == 0) + biodone(bp); + freerq(rq); + return -1; + } { /* XXX */ + int result; + int s = splhigh(); + result = launch_requests(rq, reviveok); /* now start the requests if we can */ + splx(s); + return result; + } + /* return launch_requests (rq, reviveok); *//* start the requests */ + } +} + +/* Call the low-level strategy routines to + * perform the requests in a struct request */ +int +launch_requests(struct request *rq, int reviveok) +{ + struct rqgroup *rqg; + int rqno; /* loop index */ + struct rqelement *rqe; /* current element */ + int s; + + /* First find out whether we're reviving, and the + * request contains a conflict. If so, we hang + * the request off plex->waitlist of the first + * plex we find which is reviving */ + if ((rq->flags & XFR_REVIVECONFLICT) /* possible revive conflict */ + &&(!reviveok)) { /* and we don't want to do it now, */ + struct volume *vol = &VOL[VOLNO(rq->bp->b_dev)]; + struct plex *plex; + int plexno; + + for (plexno = 0; plexno < vol->plexes; plexno++) { /* find the reviving plex */ + plex = &PLEX[vol->plex[plexno]]; + if (plex->state == plex_reviving) /* found it */ + break; + } + if (plexno < vol->plexes) { /* found it? */ + struct request *waitlist = plex->waitlist; /* point to the waiting list */ + + while (waitlist->next != NULL) /* find the end */ + waitlist = waitlist->next; + waitlist->next = rq; /* hook our request there */ + return 0; /* and get out of here */ + } else /* bad vinum, bad */ + printf("vinum: can't find reviving plex for volume %s\n", vol->name); + } + rq->active = 0; /* nothing yet */ + /* XXX This is probably due to a bug */ + if (rq->rqg == NULL) { /* no request */ + abortrequest(rq, EINVAL); + return -1; + } +#if DEBUG + if (debug & DEBUG_ADDRESSES) + printf("Request: %x\n%s dev 0x%x, offset 0x%x, length %ld\n", + (u_int) rq, + rq->bp->b_flags & B_READ ? "Read" : "Write", + rq->bp->b_dev, + rq->bp->b_blkno, + rq->bp->b_bcount); /* XXX */ + vinum_conf.lastrq = (int) rq; + vinum_conf.lastbuf = rq->bp; + if (debug & DEBUG_LASTREQS) + logrq(loginfo_user_bpl, rq->bp, rq->bp); +#endif + for (rqg = rq->rqg; rqg != NULL; rqg = rqg->next) { /* through the whole request chain */ + rqg->active = rqg->count; /* they're all active */ + rq->active++; /* one more active request group */ + for (rqno = 0; rqno < rqg->count; rqno++) { + rqe = &rqg->rqe[rqno]; + if (rqe->flags & XFR_BAD_SUBDISK) /* this subdisk is bad, */ + rqg->active--; /* one less active request */ + else { + struct drive *drive = &DRIVE[rqe->driveno]; /* drive to access */ + if ((rqe->b.b_flags & B_READ) == 0) + rqe->b.b_vp->v_numoutput++; /* one more output going */ + rqe->b.b_flags |= B_ORDERED; /* XXX chase SCSI driver */ +#if DEBUG + if (debug & DEBUG_ADDRESSES) + printf(" %s dev 0x%x, sd %d, offset 0x%x, devoffset 0x%x, length %ld\n", + rqe->b.b_flags & B_READ ? "Read" : "Write", + rqe->b.b_dev, + rqe->sdno, + (u_int) (rqe->b.b_blkno - SD[rqe->sdno].driveoffset), + rqe->b.b_blkno, + rqe->b.b_bcount); /* XXX */ + if (debug & DEBUG_NUMOUTPUT) + printf(" vinumstart sd %d numoutput %ld\n", + rqe->sdno, + rqe->b.b_vp->v_numoutput); + if (debug & DEBUG_LASTREQS) + logrq(loginfo_rqe, rqe, rq->bp); +#endif + /* fire off the request */ + s = splbio(); + (*bdevsw[major(rqe->b.b_dev)]->d_strategy) (&rqe->b); + splx(s); + } + /* XXX Do we need caching? Think about this more */ + } + } + return 0; +} + +/* define the low-level requests needed to perform a + * high-level I/O operation for a specific plex 'plexno'. + * + * Return 0 if all subdisks involved in the request are up, 1 if some + * subdisks are not up, and -1 if the request is at least partially + * outside the bounds of the subdisks. + * + * Modify the pointer *diskstart to point to the end address. On + * read, return on the first bad subdisk, so that the caller + * (build_read_request) can try alternatives. + * + * On entry to this routine, the rqg structures are not assigned. The + * assignment is performed by expandrq(). Strictly speaking, the + * elements rqe->sdno of all entries should be set to -1, since 0 + * (from bzero) is a valid subdisk number. We avoid this problem by + * initializing the ones we use, and not looking at the others (index + * >= rqg->requests). + */ +enum requeststatus +bre(struct request *rq, + int plexno, + daddr_t * diskaddr, + daddr_t diskend) +{ + BROKEN_GDB; + int sdno; + struct sd *sd; + struct rqgroup *rqg; + struct buf *bp; /* user's bp */ + struct plex *plex; + enum requeststatus status; /* return value */ + daddr_t plexoffset; /* offset of transfer in plex */ + daddr_t stripebase; /* base address of stripe (1st subdisk) */ + daddr_t stripeoffset; /* offset in stripe */ + daddr_t blockoffset; /* offset in stripe on subdisk */ + struct rqelement *rqe; /* point to this request information */ + daddr_t diskstart = *diskaddr; /* remember where this transfer starts */ + + bp = rq->bp; /* buffer pointer */ + status = REQUEST_OK; /* return value: OK until proven otherwise */ + plex = &PLEX[plexno]; /* point to the plex */ + + switch (plex->organization) { + case plex_concat: + for (sdno = 0; sdno < plex->subdisks; sdno++) { + sd = &SD[plex->sdnos[sdno]]; + if ((*diskaddr < (sd->plexoffset + sd->sectors)) /* The request starts before the end of this */ + &&(diskend > sd->plexoffset)) { /* subdisk and ends after the start of this sd */ + if ((sd->state != sd_up) || (plex->state != plex_up)) { + enum requeststatus s; + + s = checksdstate(sd, rq, *diskaddr, diskend); /* do we need to change state? */ + if (s) /* give up? */ + return s; /* yup */ + } + rqg = allocrqg(rq, 1); /* space for the request */ + if (rqg == NULL) { /* malloc failed */ + bp->b_flags |= B_ERROR; + bp->b_error = ENOMEM; + biodone(bp); + return REQUEST_ENOMEM; + } + rqg->plexno = plexno; + + rqe = &rqg->rqe[0]; /* point to the element */ + rqe->rqg = rqg; /* group */ + rqe->sdno = sd->sdno; /* put in the subdisk number */ + plexoffset = max(sd->plexoffset, *diskaddr); /* start offset in plex */ + rqe->sdoffset = plexoffset - sd->plexoffset; /* start offset in subdisk */ + rqe->useroffset = plexoffset - diskstart; /* start offset in user buffer */ + rqe->dataoffset = 0; + rqe->datalen = min(diskend - *diskaddr, /* number of sectors to transfer in this sd */ + sd->sectors - rqe->sdoffset); + rqe->groupoffset = 0; /* no groups for concatenated plexes */ + rqe->grouplen = 0; + rqe->buflen = rqe->datalen; /* buffer length is data buffer length */ + rqe->flags = 0; + rqe->driveno = sd->driveno; + *diskaddr += rqe->datalen; /* bump the address */ + if (build_rq_buffer(rqe, plex)) { /* build the buffer */ + deallocrqg(rqg); + bp->b_flags |= B_ERROR; + bp->b_error = ENOMEM; + biodone(bp); + return REQUEST_ENOMEM; /* can't do it */ + } + } + if (*diskaddr > diskend) /* we're finished, */ + break; /* get out of here */ + } + break; + + case plex_striped: + { + while (*diskaddr < diskend) { /* until we get it all sorted out */ + /* The offset of the start address from + * the start of the stripe */ + stripeoffset = *diskaddr % (plex->stripesize * plex->subdisks); + + /* The plex-relative address of the + * start of the stripe */ + stripebase = *diskaddr - stripeoffset; + + /* The number of the subdisk in which + * the start is located */ + sdno = stripeoffset / plex->stripesize; + + /* The offset from the beginning of the stripe + * on this subdisk */ + blockoffset = stripeoffset % plex->stripesize; + + sd = &SD[plex->sdnos[sdno]]; /* the subdisk in question */ + if ((sd->state != sd_up) || (plex->state != plex_up)) { + enum requeststatus s; + + s = checksdstate(sd, rq, *diskaddr, diskend); /* do we need to change state? */ + if (s) /* give up? */ + return s; /* yup */ + } + rqg = allocrqg(rq, 1); /* space for the request */ + if (rqg == NULL) { /* malloc failed */ + bp->b_flags |= B_ERROR; + bp->b_error = ENOMEM; + biodone(bp); + return REQUEST_ENOMEM; + } + rqg->plexno = plexno; + + rqe = &rqg->rqe[0]; /* point to the element */ + rqe->rqg = rqg; + rqe->sdoffset = stripebase / plex->subdisks + blockoffset; /* start offset in this subdisk */ + rqe->useroffset = *diskaddr - diskstart; /* The offset of the start in the user buffer */ + rqe->dataoffset = 0; + rqe->datalen = min(diskend - *diskaddr, /* the amount remaining to transfer */ + plex->stripesize - blockoffset); /* and the amount left in this stripe */ + rqe->groupoffset = 0; /* no groups for striped plexes */ + rqe->grouplen = 0; + rqe->buflen = rqe->datalen; /* buffer length is data buffer length */ + rqe->flags = 0; + rqe->sdno = sd->sdno; /* put in the subdisk number */ + rqe->driveno = sd->driveno; + + if (rqe->sdoffset >= sd->sectors) { /* starts beyond the end of the subdisk? */ + deallocrqg(rqg); + return REQUEST_EOF; + } else if (rqe->sdoffset + rqe->datalen > sd->sectors) /* ends beyond the end of the subdisk? */ + rqe->datalen = sd->sectors - rqe->sdoffset; /* yes, truncate */ + + if (build_rq_buffer(rqe, plex)) { /* build the buffer */ + deallocrqg(rqg); + bp->b_flags |= B_ERROR; + bp->b_error = ENOMEM; + biodone(bp); + return REQUEST_ENOMEM; /* can't do it */ + } + *diskaddr += rqe->datalen; /* look at the remainder */ + if (*diskaddr < diskend) { /* didn't finish the request on this stripe */ + plex->multiblock++; /* count another one */ + if (sdno == plex->subdisks - 1) /* last subdisk, */ + plex->multistripe++; /* another stripe as well */ + } + } + } + break; + + + default: + printf("vinum: invalid plex type in bre"); + } + + return status; +} + +/* Build up a request structure for reading volumes. + * This function is not needed for plex reads, since there's + * no recovery if a plex read can't be satisified. */ +enum requeststatus +build_read_request(struct request *rq, /* request */ + int plexindex) +{ /* index in the volume's plex table */ + BROKEN_GDB; + struct buf *bp; + daddr_t startaddr; /* offset of previous part of transfer */ + daddr_t diskaddr; /* offset of current part of transfer */ + daddr_t diskend; /* and end offset of transfer */ + int plexno; /* plex index in vinum_conf */ + struct rqgroup *rqg; /* point to the request we're working on */ + struct volume *vol; /* volume in question */ + off_t oldstart; /* note where we started */ + int recovered = 0; /* set if we recover a read */ + enum requeststatus status = REQUEST_OK; + + bp = rq->bp; /* buffer pointer */ + diskaddr = bp->b_blkno; /* start offset of transfer */ + diskend = diskaddr + (bp->b_bcount / DEV_BSIZE); /* and end offset of transfer */ + rqg = &rq->rqg[plexindex]; /* plex request */ + vol = &VOL[rq->volplex.volno]; /* point to volume */ + + while (diskaddr < diskend) { /* build up request components */ + startaddr = diskaddr; + status = bre(rq, vol->plex[plexindex], &diskaddr, diskend); /* build up a request */ + switch (status) { + case REQUEST_OK: + continue; + + case REQUEST_RECOVERED: + recovered = 1; + break; + + case REQUEST_EOF: + case REQUEST_ENOMEM: + return status; + + /* if we get here, we have either had a failure or + * a RAID 5 recovery. We don't want to use the + * recovery, because it's expensive, so first we + * check if we have alternatives */ + case REQUEST_DOWN: /* can't access the plex */ + if (vol != NULL) { /* and this is volume I/O */ + /* Try to satisfy the request + * from another plex */ + for (plexno = 0; plexno < vol->plexes; plexno++) { + diskaddr = startaddr; /* start at the beginning again */ + oldstart = startaddr; /* and note where that was */ + if (plexno != plexindex) { /* don't try this plex again */ + bre(rq, vol->plex[plexno], &diskaddr, diskend); /* try a request */ + if (diskaddr > oldstart) { /* we satisfied another part */ + recovered = 1; /* we recovered from the problem */ + status = REQUEST_OK; /* don't complain about it */ + break; + } + } + if (plexno == (vol->plexes - 1)) /* couldn't satisfy the request */ + return REQUEST_DOWN; /* failed */ + } + } else + return REQUEST_DOWN; /* bad luck */ + } + if (recovered) + vol->recovered_reads += recovered; /* adjust our recovery count */ + } + return status; +} + +/* Build up a request structure for writes. + * Return 0 if all subdisks involved in the request are up, 1 if some + * subdisks are not up, and -1 if the request is at least partially + * outside the bounds of the subdisks. */ +enum requeststatus +build_write_request(struct request *rq) +{ /* request */ + BROKEN_GDB; + struct buf *bp; + daddr_t diskstart; /* offset of current part of transfer */ + daddr_t diskend; /* and end offset of transfer */ + int plexno; /* plex index in vinum_conf */ + struct volume *vol; /* volume in question */ + enum requeststatus status; + + bp = rq->bp; /* buffer pointer */ + vol = &VOL[rq->volplex.volno]; /* point to volume */ + diskend = bp->b_blkno + (bp->b_bcount / DEV_BSIZE); /* end offset of transfer */ + status = REQUEST_OK; + for (plexno = 0; plexno < vol->plexes; plexno++) { + diskstart = bp->b_blkno; /* start offset of transfer */ + status = min(status, bre(rq, /* build requests for the plex */ + vol->plex[plexno], + &diskstart, + diskend)); + } + return status; +} + +/* Fill in the struct buf part of a request element. */ +enum requeststatus +build_rq_buffer(struct rqelement *rqe, struct plex *plex) +{ + BROKEN_GDB; + struct sd *sd; /* point to subdisk */ + struct volume *vol; + struct buf *bp; + struct buf *ubp; /* user (high level) buffer header */ + + vol = &VOL[rqe->rqg->rq->volplex.volno]; + sd = &SD[rqe->sdno]; /* point to subdisk */ + bp = &rqe->b; + ubp = rqe->rqg->rq->bp; /* pointer to user buffer header */ + + /* Initialize the buf struct */ + bzero(&rqe->b, sizeof(struct buf)); + bp->b_proc = ubp->b_proc; /* process pointer */ + bp->b_flags = ubp->b_flags & (B_NOCACHE | B_READ | B_ASYNC); /* copy these flags from user bp */ + bp->b_flags |= B_CALL | B_BUSY; /* inform us when it's done */ + if (plex->state == plex_reviving) + bp->b_flags |= B_ORDERED; /* keep request order if we're reviving */ + bp->b_iodone = complete_rqe; /* by calling us here */ + bp->b_dev = DRIVE[rqe->driveno].dev; /* drive device */ + bp->b_blkno = rqe->sdoffset + sd->driveoffset; /* start address */ + bp->b_bcount = rqe->buflen << DEV_BSHIFT; /* number of bytes to transfer */ + bp->b_resid = bp->b_bcount; /* and it's still all waiting */ + bp->b_bufsize = bp->b_bcount; /* and buffer size */ + bp->b_vp = DRIVE[rqe->driveno].vp; /* drive vnode */ + bp->b_rcred = FSCRED; /* we have the file system credentials */ + bp->b_wcred = FSCRED; /* we have the file system credentials */ + + if (rqe->flags & XFR_MALLOCED) { /* this operation requires a malloced buffer */ + bp->b_data = Malloc(bp->b_bcount); /* get a buffer to put it in */ + if (bp->b_data == NULL) { /* failed */ + Debugger("XXX"); + abortrequest(rqe->rqg->rq, ENOMEM); + return REQUEST_ENOMEM; /* no memory */ + } + } else + /* Point directly to user buffer data. This means + * that we don't need to do anything when we have + * finished the transfer */ + bp->b_data = ubp->b_data + rqe->useroffset * DEV_BSIZE; + return 0; +} +/* Abort a request: free resources and complete the + * user request with the specified error */ +int +abortrequest(struct request *rq, int error) +{ + struct buf *bp = rq->bp; /* user buffer */ + + bp->b_flags |= B_ERROR; + bp->b_error = error; + freerq(rq); /* free everything we're doing */ + biodone(bp); + return error; /* and give up */ +} + +/* Check that our transfer will cover the + * complete address space of the user request. + * + * Return 1 if it can, otherwise 0 */ +int +check_range_covered(struct request *rq) +{ + /* XXX */ + return 1; +} + +/* Perform I/O on a subdisk */ +void +sdio(struct buf *bp) +{ + int s; /* spl */ + struct sd *sd; + struct sdbuf *sbp; + daddr_t endoffset; + struct drive *drive; + + sd = &SD[SDNO(bp->b_dev)]; /* point to the subdisk */ + drive = &DRIVE[sd->driveno]; + + if (drive->state != drive_up) { /* XXX until we get the states fixed */ + set_sd_state(SDNO(bp->b_dev), sd_obsolete, setstate_force); + bp->b_flags |= B_ERROR; + bp->b_error = EIO; + biodone(bp); + return; + } + /* XXX decide which states we will really accept here. up + * implies it could be involved with a plex, in which + * case we don't want to dick with it */ + if ((sd->state != sd_up) + && (sd->state != sd_initializing) + && (sd->state != sd_reborn)) { /* we can't access it */ + bp->b_flags |= B_ERROR; + bp->b_flags = EIO; + if (bp->b_flags & B_BUSY) /* XXX why isn't this always the case? */ + biodone(bp); + return; + } + /* Get a buffer */ + sbp = (struct sdbuf *) Malloc(sizeof(struct sdbuf)); + if (sbp == NULL) { + bp->b_flags |= B_ERROR; + bp->b_error = ENOMEM; + biodone(bp); + return; + } + bcopy(bp, &sbp->b, sizeof(struct buf)); /* start with the user's buffer */ + sbp->b.b_flags |= B_CALL; /* tell us when it's done */ + sbp->b.b_iodone = sdio_done; /* here */ + sbp->b.b_dev = DRIVE[sd->driveno].dev; /* device */ + sbp->b.b_vp = DRIVE[sd->driveno].vp; /* vnode */ + sbp->b.b_blkno += sd->driveoffset; + sbp->bp = bp; /* note the address of the original header */ + sbp->sdno = sd->sdno; /* note for statistics */ + sbp->driveno = sd->driveno; + endoffset = bp->b_blkno + sbp->b.b_bcount / DEV_BSIZE; /* final sector offset */ + if (endoffset > sd->sectors) { /* beyond the end */ + sbp->b.b_bcount -= (endoffset - sd->sectors) * DEV_BSIZE; /* trim */ + if (sbp->b.b_bcount <= 0) { /* nothing to transfer */ + bp->b_resid = bp->b_bcount; /* nothing transferred */ + /* XXX Grrr. This doesn't seem to work. Return + * an error after all */ + bp->b_flags |= B_ERROR; + bp->b_error = ENOSPC; + biodone(bp); + Free(sbp); + return; + } + } + if ((sbp->b.b_flags & B_READ) == 0) /* write */ + sbp->b.b_vp->v_numoutput++; /* one more output going */ +#if DEBUG + if (debug & DEBUG_ADDRESSES) + printf(" %s dev 0x%x, sd %d, offset 0x%x, devoffset 0x%x, length %ld\n", + sbp->b.b_flags & B_READ ? "Read" : "Write", + sbp->b.b_dev, + sbp->sdno, + (u_int) (sbp->b.b_blkno - SD[sbp->sdno].driveoffset), + (int) sbp->b.b_blkno, + sbp->b.b_bcount); /* XXX */ + if (debug & DEBUG_NUMOUTPUT) + printf(" vinumstart sd %d numoutput %ld\n", + sbp->sdno, + sbp->b.b_vp->v_numoutput); +#endif + s = splbio(); + (*bdevsw[major(sbp->b.b_dev)]->d_strategy) (&sbp->b); + splx(s); +} + +/* Simplified version of bounds_check_with_label + * Determine the size of the transfer, and make sure it is + * within the boundaries of the partition. Adjust transfer + * if needed, and signal errors or early completion. + * + * Volumes are simpler than disk slices: they only contain + * one component (though we call them a, b and c to make + * system utilities happy), and they always take up the + * complete space of the "partition". + * + * I'm still not happy with this: why should the label be + * protected? If it weren't so damned difficult to write + * one in the first pleace (because it's protected), it wouldn't + * be a problem. + */ +int +vinum_bounds_check(struct buf *bp, struct volume *vol) +{ + int maxsize = vol->size; /* size of the partition (sectors) */ + int size = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT; /* size of this request (sectors) */ + + /* Would this transfer overwrite the disk label? */ + if (bp->b_blkno <= LABELSECTOR /* starts before or at the label */ +#if LABELSECTOR != 0 + && bp->b_blkno + size > LABELSECTOR /* and finishes after */ +#endif + && (!(vol->flags & VF_RAW)) /* and it's not raw */ + &&major(bp->b_dev) == BDEV_MAJOR /* and it's the block device */ + && (bp->b_flags & B_READ) == 0 /* and it's a write */ + && (!vol->flags & (VF_WLABEL | VF_LABELLING))) { /* and we're not allowed to write the label */ + bp->b_error = EROFS; /* read-only */ + bp->b_flags |= B_ERROR; + return -1; + } + if (size == 0) /* no transfer specified, */ + return 0; /* treat as EOF */ + /* beyond partition? */ + if (bp->b_blkno < 0 /* negative start */ + || bp->b_blkno + size > maxsize) { /* or goes beyond the end of the partition */ + /* if exactly at end of disk, return an EOF */ + if (bp->b_blkno == maxsize) { + bp->b_resid = bp->b_bcount; + return 0; + } + /* or truncate if part of it fits */ + size = maxsize - bp->b_blkno; + if (size <= 0) { /* nothing to transfer */ + bp->b_error = EINVAL; + bp->b_flags |= B_ERROR; + return -1; + } + bp->b_bcount = size << DEV_BSHIFT; + } + bp->b_pblkno = bp->b_blkno; + return 1; +} + +/* Allocate a request group and hook + * it in in the list for rq */ +struct rqgroup * +allocrqg(struct request *rq, int elements) +{ + struct rqgroup *rqg; /* the one we're going to allocate */ + int size = sizeof(struct rqgroup) + elements * sizeof(struct rqelement); + + rqg = (struct rqgroup *) Malloc(size); + if (rqg != NULL) { /* malloc OK, */ + if (rq->rqg) /* we already have requests */ + rq->lrqg->next = rqg; /* hang it off the end */ + else /* first request */ + rq->rqg = rqg; /* at the start */ + rq->lrqg = rqg; /* this one is the last in the list */ + + bzero(rqg, size); /* no old junk */ + rqg->rq = rq; /* point back to the parent request */ + rqg->count = elements; /* number of requests in the group */ + } else + Debugger("XXX"); + return rqg; +} + +/* Deallocate a request group out of a chain. We do + * this by linear search: the chain is short, this + * almost never happens, and currently it can only + * happen to the first member of the chain. */ +void +deallocrqg(struct rqgroup *rqg) +{ + struct rqgroup *rqgc = rqg->rq->rqg; /* point to the request chain */ + + if (rqg->rq->rqg == rqg) /* we're first in line */ + rqg->rq->rqg = rqg->next; /* unhook ourselves */ + else { + while (rqgc->next != rqg) /* find the group */ + rqgc = rqgc->next; + rqgc->next = rqg->next; + } + Free(rqgc); +} + +/* Character device interface */ +int +vinumread(dev_t dev, struct uio *uio, int ioflag) +{ + return (physio(vinumstrategy, NULL, dev, 1, minphys, uio)); +} + +int +vinumwrite(dev_t dev, struct uio *uio, int ioflag) +{ + return (physio(vinumstrategy, NULL, dev, 0, minphys, uio)); +} |
