diff options
Diffstat (limited to 'sys/modules/vinum/request.c')
-rw-r--r-- | sys/modules/vinum/request.c | 882 |
1 files changed, 0 insertions, 882 deletions
diff --git a/sys/modules/vinum/request.c b/sys/modules/vinum/request.c deleted file mode 100644 index 589eb3f..0000000 --- a/sys/modules/vinum/request.c +++ /dev/null @@ -1,882 +0,0 @@ -/* 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 1.17 1998/08/13 06:04:47 grog Exp grog $ - */ - -#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); - -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; - - 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; - - /* 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; - } - return launch_requests(rq, reviveok); /* now start the requests if we can */ - } 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; - } - 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\nWrite dev 0x%x, offset 0x%x, length %ld\n", - (u_int) rq, - rq->bp->b_dev, - rq->bp->b_blkno, - rq->bp->b_bcount); /* XXX */ - vinum_conf.lastrq = (int) rq; - vinum_conf.lastbuf = 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 */ -#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); -#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)); -} |