Don't loose count when adding too many plexes to a volume.

[dragonfly.git] / sys / dev / raid / vinum / vinumconfig.c

/*
 * To do:
 *
 * Don't store drive configuration on the config DB: read each drive's header
 * to decide where it is.
 *
 * Accept any old crap in the config_<foo> functions, and complain when
 * we try to bring it up.
 *
 * When trying to bring volumes up, check that the complete address range
 * is covered.
 */
/*-
 * 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: vinumconfig.c,v 1.30 2000/05/01 09:45:50 grog Exp grog $
 * $FreeBSD: src/sys/dev/vinum/vinumconfig.c,v 1.32.2.6 2002/02/03 00:43:35 grog Exp $
 * $DragonFly: src/sys/dev/raid/vinum/vinumconfig.c,v 1.12 2007/06/07 22:58:00 corecode Exp $
 */

#define STATIC static

#include "vinumhdr.h"
#include "request.h"

#define MAXTOKEN 64                                         /* maximum number of tokens in a line */

/*
 * We can afford the luxury of global variables here,
 * since start_config ensures that these functions
 * are single-threaded.
 */

/* These are indices in vinum_conf of the last-mentioned of each kind of object */
static int current_drive;                                   /* note the last drive we mention, for
                                                            * some defaults */
static int current_plex;                                    /* and the same for the last plex */
static int current_volume;                                  /* and the last volme */
static struct _ioctl_reply *ioctl_reply;                    /* struct to return via ioctl */


/* These values are used by most of these routines, so set them as globals */
static char *token[MAXTOKEN];                               /* pointers to individual tokens */
static int tokens;                                          /* number of tokens */

#define TOCONS  0x01
#define TOTTY   0x02
#define TOLOG   0x04

struct putchar_arg {
    int flags;
    struct tty *tty;
};

#define MSG_MAX 1024                                        /* maximum length of a formatted message */
/*
 * Format an error message and return to the user in the reply.
 * CARE: This routine is designed to be called only from the
 * configuration routines, so it assumes it's the owner of
 * the configuration lock, and unlocks it on exit
 */
void
throw_rude_remark(int error, char *msg,...)
{
    int retval;
    __va_list ap;
    char *text;
    static int finishing;                                   /* don't recurse */
    int was_finishing;

    if ((vinum_conf.flags & VF_LOCKED) == 0)                /* bug catcher */
        panic ("throw_rude_remark: called without config lock");
    __va_start(ap, msg);
    if ((ioctl_reply != NULL)                               /* we're called from the user */
    &&(!(vinum_conf.flags & VF_READING_CONFIG))) {          /* and not reading from disk: return msg */
        /*
         * We can't just format to ioctl_reply, since it
         * may contain our input parameters
         */
        text = Malloc(MSG_MAX);
        if (text == NULL) {
            log(LOG_ERR, "vinum: can't allocate error message buffer\n");
            kprintf("vinum: ");
            kvprintf(msg, ap);                              /* print to the console */
            kprintf("\n");
        } else {
            retval = kvcprintf(msg, NULL, (void *) text, 10, ap);
            text[retval] = '\0';                            /* delimit */
            strcpy(ioctl_reply->msg, text);
            ioctl_reply->error = error;                     /* first byte is the error number */
            Free(text);
        }
    } else {
        kprintf("vinum: ");
        kvprintf(msg, ap);                                  /* print to the console */
        kprintf("\n");
    }
    __va_end(ap);

    if (vinum_conf.flags & VF_READING_CONFIG) {             /* go through to the bitter end, */
        if ((vinum_conf.flags & VF_READING_CONFIG)          /* we're reading from disk, */
        &&((daemon_options & daemon_noupdate) == 0)) {
            log(LOG_NOTICE, "Disabling configuration updates\n");
            daemon_options |= daemon_noupdate;
        }
        return;
    }
    /*
     * We have a problem here: we want to unlock the
     * configuration, which implies tidying up, but
     * if we find an error while tidying up, we could
     * recurse for ever.  Use this kludge to only try
     * once
     */
    was_finishing = finishing;
    finishing = 1;
    finish_config(was_finishing);                           /* unlock anything we may be holding */
    finishing = was_finishing;
    longjmp(command_fail, error);
}

/*
 * Check a volume to see if the plex is already assigned to it.
 * Return index in volume->plex, or -1 if not assigned
 */
int
my_plex(int volno, int plexno)
{
    int i;
    struct volume *vol;

    vol = &VOL[volno];                                      /* point to volno */
    for (i = 0; i < vol->plexes; i++)
        if (vol->plex[i] == plexno)
            return i;
    return -1;                                              /* not found */
}

/*
 * Check a plex to see if the subdisk is already assigned to it.
 * Return index in plex->sd, or -1 if not assigned
 */
int
my_sd(int plexno, int sdno)
{
    int i;
    struct plex *plex;

    plex = &PLEX[plexno];
    for (i = 0; i < plex->subdisks; i++)
        if (plex->sdnos[i] == sdno)
            return i;
    return -1;                                              /* not found */
}

/* Add plex to the volume if possible */
int
give_plex_to_volume(int volno, int plexno)
{
    struct volume *vol;
    int i;

    /*
     * It's not an error for the plex to already
     * belong to the volume, but we need to check a
     * number of things to make sure it's done right.
     * Some day.
     */
    if (my_plex(volno, plexno) >= 0)
        return plexno;                                      /* that's it */

    vol = &VOL[volno];                                      /* point to volume */
    if (vol->plexes == MAXPLEX)                             /* all plexes allocated */
        throw_rude_remark(ENOSPC,
            "Too many plexes for volume %s",
            vol->name);
    else if ((vol->plexes > 0)                              /* we have other plexes */
    &&((vol->flags & VF_CONFIG_SETUPSTATE) == 0))           /* and we're not setting up state */
        invalidate_subdisks(&PLEX[plexno], sd_stale);       /* make the subdisks invalid */
    vol->plex[vol->plexes] = plexno;                        /* this one */
    vol->plexes++;                                          /* add another plex */
    PLEX[plexno].volno = volno;                             /* note the number of our volume */

    /* Find out how big our volume is */
    for (i = 0; i < vol->plexes; i++)
        vol->size = max(vol->size, PLEX[vol->plex[i]].length);
    return vol->plexes - 1;                                 /* and return its index */
}

/*
 * Add subdisk to a plex if possible
 */
int
give_sd_to_plex(int plexno, int sdno)
{
    int i;
    struct plex *plex;
    struct sd *sd;

    /*
     * It's not an error for the sd to already
     * belong to the plex, but we need to check a
     * number of things to make sure it's done right.
     * Some day.
     */
    i = my_sd(plexno, sdno);
    if (i >= 0)                                             /* does it already belong to us? */
        return i;                                           /* that's it */

    plex = &PLEX[plexno];                                   /* point to the plex */
    sd = &SD[sdno];                                         /* and the subdisk */

    /* Do we have an offset?  Otherwise put it after the last one */
    if (sd->plexoffset < 0) {                               /* no offset specified */
        if (plex->subdisks > 0) {
            struct sd *lastsd = &SD[plex->sdnos[plex->subdisks - 1]]; /* last subdisk */

            if (plex->organization == plex_concat)          /* concat, */
                sd->plexoffset = lastsd->sectors + lastsd->plexoffset; /* starts here */
            else                                            /* striped, RAID-4 or RAID-5 */
                sd->plexoffset = plex->stripesize * plex->subdisks; /* starts here */
        } else                                              /* first subdisk */
            sd->plexoffset = 0;                             /* start at the beginning */
    }
    if (plex->subdisks == MAXSD)                            /* we already have our maximum */
        throw_rude_remark(ENOSPC,                           /* crap out */
            "Can't add %s to %s: plex full",
            sd->name,
            plex->name);

    plex->subdisks++;                                       /* another entry */
    if (plex->subdisks >= plex->subdisks_allocated)         /* need more space */
        EXPAND(plex->sdnos, int, plex->subdisks_allocated, INITIAL_SUBDISKS_IN_PLEX);

    /* Adjust size of plex and volume. */
    if (isparity(plex))                                     /* RAID-4 or RAID-5 */
        plex->length = (plex->subdisks - 1) * sd->sectors;  /* size is one disk short */
    else
        plex->length += sd->sectors;                        /* plex gets this much bigger */
    if (plex->volno >= 0)                                   /* we have a volume */
        VOL[plex->volno].size = max(VOL[plex->volno].size, plex->length); /* adjust its size */

    /*
     * We need to check that the subdisks don't overlap,
     * but we can't do that until a point where we *must*
     * know the size of all the subdisks.  That's not
     * here.  But we need to sort them by offset
     */
    for (i = 0; i < plex->subdisks - 1; i++) {
        if (sd->plexoffset < SD[plex->sdnos[i]].plexoffset) { /* it fits before this one */
            /* First move any remaining subdisks by one */
            int j;

            for (j = plex->subdisks - 1; j > i; j--)        /* move up one at a time */
                plex->sdnos[j] = plex->sdnos[j - 1];
            plex->sdnos[i] = sdno;
            sd->plexsdno = i;                               /* note where we are in the subdisk */
            return i;
        }
    }

    /*
     * The plex doesn't have any subdisk with a
     * larger offset.  Insert it here.
     */
    plex->sdnos[i] = sdno;
    sd->plexsdno = i;                                       /* note where we are in the subdisk */
    sd->plexno = plex->plexno;                              /* and who we belong to */
    return i;
}

/*
 * Add a subdisk to drive if possible.  The
 * pointer to the drive must already be stored in
 * the sd structure, but the drive doesn't know
 * about the subdisk yet.
 */
void
give_sd_to_drive(int sdno)
{
    struct sd *sd;                                          /* pointer to subdisk */
    struct drive *drive;                                    /* and drive */
    int fe;                                                 /* index in free list */
    int sfe;                                                /* and index of subdisk when assigning max */

    sd = &SD[sdno];                                         /* point to sd */
    drive = &DRIVE[sd->driveno];                            /* and drive */

    if (drive->state != drive_up) {
        update_sd_state(sdno);                              /* that crashes the subdisk */
        return;
    }
    if (drive->flags & VF_HOTSPARE)                         /* the drive is a hot spare, */
        throw_rude_remark(ENOSPC,
            "Can't place %s on hot spare drive %s",
            sd->name,
            drive->label.name);
    if ((drive->sectors_available == 0)                     /* no space left */
    ||(sd->sectors > drive->sectors_available)) {           /* or too big, */
        sd->driveoffset = -1;                               /* don't be confusing */
        free_sd(sd->sdno);
        throw_rude_remark(ENOSPC, "No space for %s on %s", sd->name, drive->label.name);
        return;                                             /* in case we come back here */
    }
    drive->subdisks_used++;                                 /* one more subdisk */

    if (sd->sectors == 0) {                                 /* take the largest chunk */
        sfe = 0;                                            /* to keep the compiler happy */
        for (fe = 0; fe < drive->freelist_entries; fe++) {
            if (drive->freelist[fe].sectors >= sd->sectors) { /* more space here */
                sd->sectors = drive->freelist[fe].sectors;  /* take it */
                sd->driveoffset = drive->freelist[fe].offset;
                sfe = fe;                                   /* and note the index for later */
            }
        }
        if (sd->sectors == 0) {                             /* no luck, */
            sd->driveoffset = -1;                           /* don't be confusing */
            free_sd(sd->sdno);
            throw_rude_remark(ENOSPC,                       /* give up */
                "No space for %s on %s",
                sd->name,
                drive->label.name);
        }
        if (sfe < (drive->freelist_entries - 1))            /* not the last one, */
            bcopy(&drive->freelist[sfe + 1],
                &drive->freelist[sfe],
                (drive->freelist_entries - sfe) * sizeof(struct drive_freelist));
        drive->freelist_entries--;                          /* one less entry */
        drive->sectors_available -= sd->sectors;            /* and note how much less space we have */
    } else if (sd->driveoffset < 0) {                       /* no offset specified, find one */
        for (fe = 0; fe < drive->freelist_entries; fe++) {
            if (drive->freelist[fe].sectors >= sd->sectors) { /* it'll fit here */
                sd->driveoffset = drive->freelist[fe].offset;
                if (sd->sectors == drive->freelist[fe].sectors) { /* used up the entire entry */
                    if (fe < (drive->freelist_entries - 1)) /* not the last one, */
                        bcopy(&drive->freelist[fe + 1],
                            &drive->freelist[fe],
                            (drive->freelist_entries - fe) * sizeof(struct drive_freelist));
                    drive->freelist_entries--;              /* one less entry */
                } else {
                    drive->freelist[fe].sectors -= sd->sectors; /* this much less space */
                    drive->freelist[fe].offset += sd->sectors; /* this much further on */
                }
                drive->sectors_available -= sd->sectors;    /* and note how much less space we have */
                break;
            }
        }
        if (sd->driveoffset < 0)
            /*
             * Didn't find anything.  Although the drive has
             * enough space, it's too fragmented
             */
        {
            free_sd(sd->sdno);
            throw_rude_remark(ENOSPC, "No space for %s on %s", sd->name, drive->label.name);
        }
    } else {                                                /* specific offset */
        /*
         * For a specific offset to work, the space must be
         * entirely in a single freelist entry.  Look for it.
         */
        u_int64_t sdend = sd->driveoffset + sd->sectors;    /* end of our subdisk */
        for (fe = 0; fe < drive->freelist_entries; fe++) {
            u_int64_t dend = drive->freelist[fe].offset + drive->freelist[fe].sectors; /* end of entry */
            if (dend >= sdend) {                            /* fits before here */
                if (drive->freelist[fe].offset > sd->driveoffset) { /* starts after the beginning of sd area */
                    sd->driveoffset = -1;                   /* don't be confusing */
                    set_sd_state(sd->sdno, sd_down, setstate_force);
                    throw_rude_remark(ENOSPC,
                        "No space for %s on drive %s at offset %lld",
                        sd->name,
                        drive->label.name,
                        sd->driveoffset);
                    return;
                }
                /*
                 * We've found the space, and we can allocate it.
                 * We don't need to say that to the subdisk, which
                 * already knows about it.  We need to tell it to
                 * the free list, though.  We have four possibilities:
                 *
                 * 1.  The subdisk exactly eats up the entry.  That's the
                 *     same as above.
                 * 2.  The subdisk starts at the beginning and leaves space
                 *     at the end.
                 * 3.  The subdisk starts after the beginning and leaves
                 *     space at the end as well: we end up with another
                 *     fragment.
                 * 4.  The subdisk leaves space at the beginning and finishes
                 *     at the end.
                 */
                drive->sectors_available -= sd->sectors;    /* note how much less space we have */
                if (sd->driveoffset == drive->freelist[fe].offset) { /* 1 or 2 */
                    if (sd->sectors == drive->freelist[fe].sectors) { /* 1: used up the entire entry */
                        if (fe < (drive->freelist_entries - 1)) /* not the last one, */
                            bcopy(&drive->freelist[fe + 1],
                                &drive->freelist[fe],
                                (drive->freelist_entries - fe) * sizeof(struct drive_freelist));
                        drive->freelist_entries--;          /* one less entry */
                    } else {                                /* 2: space at the end */
                        drive->freelist[fe].sectors -= sd->sectors; /* this much less space */
                        drive->freelist[fe].offset += sd->sectors; /* this much further on */
                    }
                } else {                                    /* 3 or 4 */
                    drive->freelist[fe].sectors = sd->driveoffset - drive->freelist[fe].offset;
                    if (dend > sdend) {                     /* 3: space at the end as well */
                        if (fe < (drive->freelist_entries - 1)) /* not the last one */
                            bcopy(&drive->freelist[fe],     /* move the rest down */
                                &drive->freelist[fe + 1],
                                (drive->freelist_entries - fe) * sizeof(struct drive_freelist));
                        drive->freelist_entries++;          /* one less entry */
                        drive->freelist[fe + 1].offset = sdend; /* second entry starts after sd */
                        drive->freelist[fe + 1].sectors = dend - sdend; /* and is this long */
                    }
                }
                break;
            }
        }
    }
    drive->opencount++;                                     /* one more subdisk attached */
}

/* Get an empty drive entry from the drive table */
int
get_empty_drive(void)
{
    int driveno;
    struct drive *drive;

    /* first see if we have one which has been deallocated */
    for (driveno = 0; driveno < vinum_conf.drives_allocated; driveno++) {
        if (DRIVE[driveno].state == drive_unallocated)      /* bingo */
            break;
    }

    if (driveno >= vinum_conf.drives_allocated)             /* we've used all our allocation */
        EXPAND(DRIVE, struct drive, vinum_conf.drives_allocated, INITIAL_DRIVES);

    /* got a drive entry.  Make it pretty */
    drive = &DRIVE[driveno];
    bzero(drive, sizeof(struct drive));
    drive->driveno = driveno;                               /* put number in structure */
    drive->flags |= VF_NEWBORN;                             /* newly born drive */
    strcpy(drive->devicename, "unknown");                   /* and make the name ``unknown'' */
    return driveno;                                         /* return the index */
}

/*
 * Find the named drive in vinum_conf.drive, return a pointer
 * return the index in vinum_conf.drive.
 * Don't mark the drive as allocated (XXX SMP)
 * If create != 0, create an entry if it doesn't exist
 */
/* XXX check if we have it open from attach */
int
find_drive(const char *name, int create)
{
    int driveno;
    struct drive *drive;

    if (name != NULL) {
        for (driveno = 0; driveno < vinum_conf.drives_allocated; driveno++) {
            drive = &DRIVE[driveno];                        /* point to drive */
            if ((drive->label.name[0] != '\0')              /* it has a name */
            &&(strcmp(drive->label.name, name) == 0)        /* and it's this one */
            &&(drive->state > drive_unallocated))           /* and it's a real one: found */
                return driveno;
        }
    }
    /* the drive isn't in the list.  Add it if he wants */
    if (create == 0)                                        /* don't want to create */
        return -1;                                          /* give up */

    driveno = get_empty_drive();
    drive = &DRIVE[driveno];
    if (name != NULL)
        bcopy(name,                                         /* put in its name */
            drive->label.name,
            min(sizeof(drive->label.name),
                strlen(name)));
    drive->state = drive_referenced;                        /* in use, nothing worthwhile there */
    return driveno;                                         /* return the index */
}

/*
 * Find a drive given its device name.
 * devname must be valid.
 * Otherwise the same as find_drive above
 */
int
find_drive_by_dev(const char *devname, int create)
{
    int driveno;
    struct drive *drive;

    for (driveno = 0; driveno < vinum_conf.drives_allocated; driveno++) {
        drive = &DRIVE[driveno];                            /* point to drive */
        if ((strcmp(drive->devicename, devname) == 0)       /* it's this device */
        &&(drive->state > drive_unallocated))               /* and it's a real one: found */
            return driveno;
    }

    /* the drive isn't in the list.  Add it if he wants */
    if (create == 0)                                        /* don't want to create */
        return -1;                                          /* give up */

    driveno = get_empty_drive();
    drive = &DRIVE[driveno];
    bcopy(devname,                                          /* put in its name */
        drive->devicename,
        min(sizeof(drive->devicename),
            strlen(devname)));
    drive->state = drive_referenced;                        /* in use, nothing worthwhile there */
    return driveno;                                         /* return the index */
}

/* Find an empty subdisk in the subdisk table */
int
get_empty_sd(void)
{
    int sdno;
    struct sd *sd;

    /* first see if we have one which has been deallocated */
    for (sdno = 0; sdno < vinum_conf.subdisks_allocated; sdno++) {
        if (SD[sdno].state == sd_unallocated)               /* bingo */
            break;
    }
    if (sdno >= vinum_conf.subdisks_allocated)
        /*
         * We've run out of space.  sdno is pointing
         * where we want it, but at the moment we
         * don't have the space.  Get it.
         */
        EXPAND(SD, struct sd, vinum_conf.subdisks_allocated, INITIAL_SUBDISKS);

    /* initialize some things */
    sd = &SD[sdno];                                         /* point to it */
    bzero(sd, sizeof(struct sd));                           /* initialize */
    sd->flags |= VF_NEWBORN;                                /* newly born subdisk */
    sd->plexno = -1;                                        /* no plex */
    sd->sectors = -1;                                       /* no space */
    sd->driveno = -1;                                       /* no drive */
    sd->plexoffset = -1;                                    /* and no offsets */
    sd->driveoffset = -1;
    return sdno;                                            /* return the index */
}

/* return a drive to the free pool */
void
free_drive(struct drive *drive)
{
    if ((drive->state > drive_referenced)                   /* real drive */
    ||(drive->flags & VF_OPEN)) {                           /* how can it be open without a state? */
        LOCKDRIVE(drive);
        if (drive->flags & VF_OPEN) {                       /* it's open, */
            close_locked_drive(drive);                      /* close it */
            drive->state = drive_down;                      /* and note the fact */
        }
        if (drive->freelist)
            Free(drive->freelist);
        bzero(drive, sizeof(struct drive));                 /* this also sets drive_unallocated */
        unlockdrive(drive);
    }
}

/*
 * Find the named subdisk in vinum_conf.sd.
 *
 * If create != 0, create an entry if it doesn't exist
 *
 * Return index in vinum_conf.sd
 */
int
find_subdisk(const char *name, int create)
{
    int sdno;
    struct sd *sd;

    for (sdno = 0; sdno < vinum_conf.subdisks_allocated; sdno++) {
        if (strcmp(SD[sdno].name, name) == 0)               /* found it */
            return sdno;
    }

    /* the subdisk isn't in the list.  Add it if he wants */
    if (create == 0)                                        /* don't want to create */
        return -1;                                          /* give up */

    /* Allocate one and insert the name */
    sdno = get_empty_sd();
    sd = &SD[sdno];
    bcopy(name, sd->name, min(sizeof(sd->name), strlen(name))); /* put in its name */
    return sdno;                                            /* return the pointer */
}

/* Return space to a drive */
void
return_drive_space(int driveno, int64_t offset, int length)
{
    struct drive *drive;
    int fe;                                                 /* free list entry */
    u_int64_t sdend;                                        /* end of our subdisk */
    u_int64_t dend;                                         /* end of our freelist entry */

    drive = &DRIVE[driveno];
    if (drive->state == drive_up) {
        sdend = offset + length;                            /* end of our subdisk */

        /* Look for where to return the sd address space */
        for (fe = 0;
            (fe < drive->freelist_entries) && (drive->freelist[fe].offset < offset);
            fe++);
        /*
         * Now we are pointing to the last entry, the first
         * with a higher offset than the subdisk, or both.
         */
        if ((fe > 1)                                        /* not the first entry */
        &&((fe == drive->freelist_entries)                  /* gone past the end */
        ||(drive->freelist[fe].offset > offset)))           /* or past the block were looking for */
            fe--;                                           /* point to the block before */
        dend = drive->freelist[fe].offset + drive->freelist[fe].sectors; /* end of the entry */

        /*
         * At this point, we are pointing to the correct
         * place in the free list.  A number of possibilities
         * exist:
         *
         * 1.  The block to be freed starts at the end of the
         *     block to which we are pointing.  This has two
         *     subcases:
         *
         * a.  The block to be freed ends at the beginning
         *     of the following block.  Merge the three
         *     areas into a single block.
         *
         * b.  The block is shorter than the space between
         *     the current block and the next one.  Enlarge
         *     the current block.
         *
         * 2.  The block to be freed starts after the end
         *     of the block.  Again, we have two cases:
         *
         * a.  It ends before the start of the following block.
         *     Create a new free block.
         *
         * b.  It ends at the start of the following block.
         *     Enlarge the following block downwards.
         *
         * When there is only one free space block, and the
         * space to be returned is before it, the pointer is
         * to a non-existent zeroth block. XXX check this
         */
        if (offset == dend) {                               /* Case 1: it starts at the end of this block */
            if ((fe < drive->freelist_entries - 1)          /* we're not the last block in the free list */
            /* and the subdisk ends at the start of the next block */
            &&(sdend == drive->freelist[fe + 1].offset)) {
                drive->freelist[fe].sectors                 /* 1a: merge all three blocks */
                    = drive->freelist[fe + 1].sectors;
                if (fe < drive->freelist_entries - 2)       /* still more blocks after next */
                    bcopy(&drive->freelist[fe + 2],         /* move down one */
                        &drive->freelist[fe + 1],
                        (drive->freelist_entries - 2 - fe)
                        * sizeof(struct drive_freelist));
                drive->freelist_entries--;                  /* one less entry in the free list */
            } else                                          /* 1b: just enlarge this block */
                drive->freelist[fe].sectors += length;
        } else {                                            /* Case 2 */
            if (offset > dend)                              /* it starts after this block */
                fe++;                                       /* so look at the next block */
            if ((fe < drive->freelist_entries)              /* we're not the last block in the free list */
            /* and the subdisk ends at the start of this block: case 4 */
            &&(sdend == drive->freelist[fe].offset)) {
                drive->freelist[fe].offset = offset;        /* it starts where the sd was */
                drive->freelist[fe].sectors += length;      /* and it's this much bigger */
            } else {                                        /* case 3: non-contiguous */
                if (fe < drive->freelist_entries)           /* not after the last block, */
                    bcopy(&drive->freelist[fe],             /* move the rest up one entry */
                        &drive->freelist[fe + 1],
                        (drive->freelist_entries - fe)
                        * sizeof(struct drive_freelist));
                drive->freelist_entries++;                  /* one less entry */
                drive->freelist[fe].offset = offset;        /* this entry represents the sd */
                drive->freelist[fe].sectors = length;
            }
        }
        drive->sectors_available += length;                 /* the sectors are now available */
    }
}

/*
 * Free an allocated sd entry.
 * This performs memory management only.  remove()
 * is responsible for checking relationships.
 */
void
free_sd(int sdno)
{
    struct sd *sd;

    sd = &SD[sdno];
    if ((sd->driveno >= 0)                                  /* we have a drive, */
    &&(sd->sectors > 0))                                    /* and some space on it */
        return_drive_space(sd->driveno,                     /* return the space */
            sd->driveoffset,
            sd->sectors);
    if (sd->plexno >= 0)
        PLEX[sd->plexno].subdisks--;                        /* one less subdisk */
    bzero(sd, sizeof(struct sd));                           /* and clear it out */
    sd->state = sd_unallocated;
    vinum_conf.subdisks_used--;                             /* one less sd */
}

/* Find an empty plex in the plex table */
int
get_empty_plex(void)
{
    int plexno;
    struct plex *plex;                                      /* if we allocate one */

    /* first see if we have one which has been deallocated */
    for (plexno = 0; plexno < vinum_conf.plexes_allocated; plexno++) {
        if (PLEX[plexno].state == plex_unallocated)         /* bingo */
            break;                                          /* and get out of here */
    }

    if (plexno >= vinum_conf.plexes_allocated)
        EXPAND(PLEX, struct plex, vinum_conf.plexes_allocated, INITIAL_PLEXES);

    /* Found a plex.  Give it an sd structure */
    plex = &PLEX[plexno];                                   /* this one is ours */
    bzero(plex, sizeof(struct plex));                       /* polish it up */
    plex->sdnos = (int *) Malloc(sizeof(int) * INITIAL_SUBDISKS_IN_PLEX); /* allocate sd table */
    CHECKALLOC(plex->sdnos, "vinum: Can't allocate plex subdisk table");
    bzero(plex->sdnos, (sizeof(int) * INITIAL_SUBDISKS_IN_PLEX)); /* do we need this? */
    plex->flags |= VF_NEWBORN;                              /* newly born plex */
    plex->subdisks = 0;                                     /* no subdisks in use */
    plex->subdisks_allocated = INITIAL_SUBDISKS_IN_PLEX;    /* and we have space for this many */
    plex->organization = plex_disorg;                       /* and it's not organized */
    plex->volno = -1;                                       /* no volume yet */
    return plexno;                                          /* return the index */
}

/*
 * Find the named plex in vinum_conf.plex
 *
 * If create != 0, create an entry if it doesn't exist
 * return index in vinum_conf.plex
 */
int
find_plex(const char *name, int create)
{
    int plexno;
    struct plex *plex;

    for (plexno = 0; plexno < vinum_conf.plexes_allocated; plexno++) {
        if (strcmp(PLEX[plexno].name, name) == 0)           /* found it */
            return plexno;
    }

    /* the plex isn't in the list.  Add it if he wants */
    if (create == 0)                                        /* don't want to create */
        return -1;                                          /* give up */

    /* Allocate one and insert the name */
    plexno = get_empty_plex();
    plex = &PLEX[plexno];                                   /* point to it */
    bcopy(name, plex->name, min(sizeof(plex->name), strlen(name))); /* put in its name */
    return plexno;                                          /* return the pointer */
}

/*
 * Free an allocated plex entry
 * and its associated memory areas
 */
void
free_plex(int plexno)
{
    struct plex *plex;

    plex = &PLEX[plexno];
    if (plex->sdnos)
        Free(plex->sdnos);
    if (plex->lock)
        Free(plex->lock);
    bzero(plex, sizeof(struct plex));                       /* and clear it out */
    plex->state = plex_unallocated;
}

/* Find an empty volume in the volume table */
int
get_empty_volume(void)
{
    int volno;
    struct volume *vol;
    int i;

    /* first see if we have one which has been deallocated */
    for (volno = 0; volno < vinum_conf.volumes_allocated; volno++) {
        if (VOL[volno].state == volume_unallocated)         /* bingo */
            break;
    }

    if (volno >= vinum_conf.volumes_allocated)
        EXPAND(VOL, struct volume, vinum_conf.volumes_allocated, INITIAL_VOLUMES);

    /* Now initialize fields */
    vol = &VOL[volno];
    bzero(vol, sizeof(struct volume));
    vol->flags |= VF_NEWBORN | VF_CREATED;                  /* newly born volume */
    vol->preferred_plex = ROUND_ROBIN_READPOL;              /* round robin */
    for (i = 0; i < MAXPLEX; i++)                           /* mark the plexes missing */
        vol->plex[i] = -1;
    return volno;                                           /* return the index */
}

/*
 * Find the named volume in vinum_conf.volume.
 *
 * If create != 0, create an entry if it doesn't exist
 * return the index in vinum_conf
 */
int
find_volume(const char *name, int create)
{
    int volno;
    struct volume *vol;

    for (volno = 0; volno < vinum_conf.volumes_allocated; volno++) {
        if (strcmp(VOL[volno].name, name) == 0)             /* found it */
            return volno;
    }

    /* the volume isn't in the list.  Add it if he wants */
    if (create == 0)                                        /* don't want to create */
        return -1;                                          /* give up */

    /* Allocate one and insert the name */
    volno = get_empty_volume();
    vol = &VOL[volno];
    bcopy(name, vol->name, min(sizeof(vol->name), strlen(name))); /* put in its name */
    vol->blocksize = DEV_BSIZE;                             /* block size of this volume */
    return volno;                                           /* return the pointer */
}

/*
 * Free an allocated volume entry
 * and its associated memory areas
 */
void
free_volume(int volno)
{
    struct volume *vol;

    vol = &VOL[volno];
    bzero(vol, sizeof(struct volume));                      /* and clear it out */
    vol->state = volume_unallocated;
}

/*
 * Handle a drive definition.  We store the information in the global variable
 * drive, so we don't need to allocate.
 *
 * If we find an error, print a message and return
 */
void
config_drive(int update)
{
    enum drive_label_info partition_status;                 /* info about the partition */
    int parameter;
    int driveno;                                            /* index of drive in vinum_conf */
    struct drive *drive;                                    /* and pointer to it */
    int otherdriveno;                                       /* index of possible second drive */
    int sdno;

    if (tokens < 2)                                         /* not enough tokens */
        throw_rude_remark(EINVAL, "Drive has no name\n");
    driveno = find_drive(token[1], 1);                      /* allocate a drive to initialize */
    drive = &DRIVE[driveno];                                /* and get a pointer */
    if (update && ((drive->flags & VF_NEWBORN) == 0))       /* this drive exists already */
        return;                                             /* don't do anything */
    drive->flags &= ~VF_NEWBORN;                            /* no longer newly born */

    if (drive->state != drive_referenced) {                 /* we already know this drive */
        /*
         * XXX Check which definition is more up-to-date.  Give
         * preference for the definition on its own drive.
         */
        return;                                             /* XXX */
    }
    for (parameter = 2; parameter < tokens; parameter++) {  /* look at the other tokens */
        switch (get_keyword(token[parameter], &keyword_set)) {
        case kw_device:
            parameter++;
            otherdriveno = find_drive_by_dev(token[parameter], 0); /* see if it exists already */
            if (otherdriveno >= 0) {                        /* yup, */
                drive->state = drive_unallocated;           /* deallocate the drive */
                throw_rude_remark(EEXIST,                   /* and complain */
                    "Drive %s would have same device as drive %s",
                    token[1],
                    DRIVE[otherdriveno].label.name);
            }
            if (drive->devicename[0] == '/') {              /* we know this drive... */
                if (strcmp(drive->devicename, token[parameter])) /* different name */
                    close_drive(drive);                     /* close it if it's open */
                else                                        /* no change */
                    break;
            }
            /* open the device and get the configuration */
            bcopy(token[parameter],                         /* insert device information */
                drive->devicename,
                min(sizeof(drive->devicename),
                    strlen(token[parameter])));
            partition_status = read_drive_label(drive, 1);
            switch (partition_status) {
            case DL_CANT_OPEN:                              /* not our kind */
                close_drive(drive);
                if (drive->lasterror == EFTYPE)             /* wrong kind of partition */
                    throw_rude_remark(drive->lasterror,
                        "Drive %s has invalid partition type",
                        drive->label.name);
                else                                        /* I/O error of some kind */
                    throw_rude_remark(drive->lasterror,
                        "Can't initialize drive %s",
                        drive->label.name);
                break;

            case DL_WRONG_DRIVE:                            /* valid drive, not the name we expected */
                if (vinum_conf.flags & VF_FORCECONFIG) {    /* but we'll accept that */
                    bcopy(token[1], drive->label.name, sizeof(drive->label.name));
                    break;
                }
                close_drive(drive);
                /*
                 * There's a potential race condition here:
                 * the rude remark refers to a field in an
                 * unallocated drive, which potentially could
                 * be reused.  This works because we're the only
                 * thread accessing the config at the moment.
                 */
                drive->state = drive_unallocated;           /* throw it away completely */
                throw_rude_remark(drive->lasterror,
                    "Incorrect drive name %s specified for drive %s",
                    token[1],
                    drive->label.name);
                break;

            case DL_DELETED_LABEL:                          /* it was a drive, but we deleted it */
            case DL_NOT_OURS:                               /* nothing to do with the rest */
            case DL_OURS:
                break;
            }
            /*
             * read_drive_label overwrites the device name.
             * If we get here, we can have the drive,
             * so put it back again
             */
            bcopy(token[parameter],
                drive->devicename,
                min(sizeof(drive->devicename),
                    strlen(token[parameter])));
            break;

        case kw_state:
            parameter++;                                    /* skip the keyword */
            if (vinum_conf.flags & VF_READING_CONFIG)
                drive->state = DriveState(token[parameter]); /* set the state */
            break;

        case kw_hotspare:                                   /* this drive is a hot spare */
            drive->flags |= VF_HOTSPARE;
            break;

        default:
            close_drive(drive);
            throw_rude_remark(EINVAL,
                "Drive %s, invalid keyword: %s",
                token[1],
                token[parameter]);
        }
    }

    if (drive->devicename[0] != '/') {
        drive->state = drive_unallocated;                   /* deallocate the drive */
        throw_rude_remark(EINVAL, "No device name for %s", drive->label.name);
    }
    vinum_conf.drives_used++;                               /* passed all hurdles: one more in use */
    /*
     * If we're replacing a drive, it could be that
     * we already have subdisks referencing this
     * drive.  Note where they should be and change
     * their state to obsolete.
     */
    for (sdno = 0; sdno < vinum_conf.subdisks_allocated; sdno++) {
        if ((SD[sdno].state > sd_referenced)
            && (SD[sdno].driveno == driveno)) {
            give_sd_to_drive(sdno);
            if (SD[sdno].state > sd_stale)
                SD[sdno].state = sd_stale;
        }
    }
}

/*
 * Handle a subdisk definition.  We store the information in the global variable
 * sd, so we don't need to allocate.
 *
 * If we find an error, print a message and return
 */
void
config_subdisk(int update)
{
    int parameter;
    int sdno;                                               /* index of sd in vinum_conf */
    struct sd *sd;                                          /* and pointer to it */
    u_int64_t size;
    int detached = 0;                                       /* set to 1 if this is a detached subdisk */
    int sdindex = -1;                                       /* index in plexes subdisk table */
    enum sdstate state = sd_unallocated;                    /* state to set, if specified */
    int autosize = 0;                                       /* set if we autosize in give_sd_to_drive */
    int namedsdno;                                          /* index of another with this name */
    char partition = 0;                                     /* partition of external subdisk */

    sdno = get_empty_sd();                                  /* allocate an SD to initialize */
    sd = &SD[sdno];                                         /* and get a pointer */

    for (parameter = 1; parameter < tokens; parameter++) {  /* look at the other tokens */
        switch (get_keyword(token[parameter], &keyword_set)) {
            /*
             * If we have a 'name' parameter, it must
             * come first, because we're too lazy to tidy
             * up dangling refs if it comes later.
             */
        case kw_name:
            namedsdno = find_subdisk(token[++parameter], 0); /* find an existing sd with this name */
            if (namedsdno >= 0) {                           /* got one */
                if (SD[namedsdno].state == sd_referenced) { /* we've been told about this one */
                    if (parameter > 2)
                        throw_rude_remark(EINVAL,
                            "sd %s: name parameter must come first\n", /* no go */
                            token[parameter]);
                    else {
                        int i;
                        struct plex *plex;                  /* for tidying up dangling references */

                        *sd = SD[namedsdno];                /* copy from the referenced one */
                        SD[namedsdno].state = sd_unallocated; /* and deallocate the referenced one */
                        plex = &PLEX[sd->plexno];           /* now take a look at our plex */
                        for (i = 0; i < plex->subdisks; i++) { /* look for the pointer */
                            if (plex->sdnos[i] == namedsdno) /* pointing to the old subdisk */
                                plex->sdnos[i] = sdno;      /* bend it to point here */
                        }
                    }
                }
                if (update)                                 /* are we updating? */
                    return;                                 /* that's OK, nothing more to do */
                else
                    throw_rude_remark(EINVAL, "Duplicate subdisk %s", token[parameter]);
            } else
                bcopy(token[parameter],
                    sd->name,
                    min(sizeof(sd->name), strlen(token[parameter])));
            break;

        case kw_detached:
            detached = 1;
            break;

        case kw_plexoffset:
            size = sizespec(token[++parameter]);
            if ((size == -1)                                /* unallocated */
            &&(vinum_conf.flags & VF_READING_CONFIG))       /* reading from disk */
                break;                                      /* invalid sd; just ignore it */
            if ((size % DEV_BSIZE) != 0)
                throw_rude_remark(EINVAL,
                    "sd %s, bad plex offset alignment: %lld",
                    sd->name,
                    (long long) size);
            else
                sd->plexoffset = size / DEV_BSIZE;
            break;

        case kw_driveoffset:
            size = sizespec(token[++parameter]);
            if ((size == -1)                                /* unallocated */
            &&(vinum_conf.flags & VF_READING_CONFIG))       /* reading from disk */
                break;                                      /* invalid sd; just ignore it */
            if ((size % DEV_BSIZE) != 0)
                throw_rude_remark(EINVAL,
                    "sd %s, bad drive offset alignment: %lld",
                    sd->name,
                    (long long) size);
            else
                sd->driveoffset = size / DEV_BSIZE;
            break;

        case kw_len:
            if (get_keyword(token[++parameter], &keyword_set) == kw_max) /* select maximum size from drive */
                size = 0;                                   /* this is how we say it :-) */
            else
                size = sizespec(token[parameter]);
            if ((size % DEV_BSIZE) != 0)
                throw_rude_remark(EINVAL, "sd %s, length %d not multiple of sector size", sd->name, size);
            else
                sd->sectors = size / DEV_BSIZE;
            /*
             * We have a problem with autosizing: we need to
             * give the drive to the plex before we give it
             * to the drive, in order to be clean if we give
             * up in the middle, but at this time the size hasn't
             * been set.  Note that we have to fix up after
             * giving the subdisk to the drive.
             */
            if (size == 0)
                autosize = 1;                               /* note that we're autosizing */
            break;

        case kw_drive:
            sd->driveno = find_drive(token[++parameter], 1); /* insert drive information */
            break;

        case kw_plex:
            sd->plexno = find_plex(token[++parameter], 1);  /* insert plex information */
            break;

            /*
             * Set the state.  We can't do this directly,
             * because give_sd_to_plex may change it
             */
        case kw_state:
            parameter++;                                    /* skip the keyword */
            if (vinum_conf.flags & VF_READING_CONFIG)
                state = SdState(token[parameter]);          /* set the state */
            break;

        case kw_partition:
            parameter++;                                    /* skip the keyword */
            if ((strlen(token[parameter]) != 1)
                || (token[parameter][0] < 'a')
                || (token[parameter][0] > 'p'))
                throw_rude_remark(EINVAL,
                    "%s: invalid partition %c",
                    sd->name,
                    token[parameter][0]);
            else
                partition = token[parameter][0];
            break;

        case kw_retryerrors:
            sd->flags |= VF_RETRYERRORS;
            break;

        default:
            throw_rude_remark(EINVAL, "%s: invalid keyword: %s", sd->name, token[parameter]);
        }
    }

    /* Check we have a drive name */
    if (sd->driveno < 0) {                                  /* didn't specify a drive */
        sd->driveno = current_drive;                        /* set to the current drive */
        if (sd->driveno < 0)                                /* no current drive? */
            throw_rude_remark(EINVAL, "Subdisk %s is not associated with a drive", sd->name);
    }
    /*
     * This is tacky.  If something goes wrong
     * with the checks, we may end up losing drive
     * space.  FIXME.
     */
    if (autosize != 0)                                      /* need to find a size, */
        give_sd_to_drive(sdno);                             /* do it before the plex */

    /*  Check for a plex name */
    if ((sd->plexno < 0)                                    /* didn't specify a plex */
    &&(!detached))                                          /* and didn't say not to, */
        sd->plexno = current_plex;                          /* set to the current plex */

    if (sd->plexno >= 0)
        sdindex = give_sd_to_plex(sd->plexno, sdno);        /* now tell the plex that it has this sd */

    sd->sdno = sdno;                                        /* point to our entry in the table */

    /* Does the subdisk have a name?  If not, give it one */
    if (sd->name[0] == '\0') {                              /* no name */
        char sdsuffix[8];                                   /* form sd name suffix here */

        /* Do we have a plex name? */
        if (sdindex >= 0)                                   /* we have a plex */
            strcpy(sd->name, PLEX[sd->plexno].name);        /* take it from there */
        else                                                /* no way */
            throw_rude_remark(EINVAL, "Unnamed sd is not associated with a plex");
        ksprintf(sdsuffix, ".s%d", sdindex);                /* form the suffix */
        strcat(sd->name, sdsuffix);                         /* and add it to the name */
    }
    /* do we have complete info for this subdisk? */
    if (sd->sectors < 0)
        throw_rude_remark(EINVAL, "sd %s has no length spec", sd->name);

    if (state != sd_unallocated)                            /* we had a specific state to set */
        sd->state = state;                                  /* do it now */
    else if (sd->state == sd_unallocated)                   /* no, nothing set yet, */
        sd->state = sd_empty;                               /* must be empty */
    if (autosize == 0)                                      /* no autoconfig, do the drive now */
        give_sd_to_drive(sdno);
    vinum_conf.subdisks_used++;                             /* one more in use */
}

/*
 * Handle a plex definition.
 */
void
config_plex(int update)
{
    int parameter;
    int plexno;                                             /* index of plex in vinum_conf */
    struct plex *plex;                                      /* and pointer to it */
    int pindex = MAXPLEX;                                   /* index in volume's plex list */
    int detached = 0;                                       /* don't give it to a volume */
    int namedplexno;
    enum plexstate state = plex_init;                       /* state to set at end */

    current_plex = -1;                                      /* forget the previous plex */
    plexno = get_empty_plex();                              /* allocate a plex */
    plex = &PLEX[plexno];                                   /* and point to it */
    plex->plexno = plexno;                                  /* and back to the config */

    for (parameter = 1; parameter < tokens; parameter++) {  /* look at the other tokens */
        switch (get_keyword(token[parameter], &keyword_set)) {
            /*
             * If we have a 'name' parameter, it must
             * come first, because we're too lazy to tidy
             * up dangling refs if it comes later.
             */
        case kw_name:
            namedplexno = find_plex(token[++parameter], 0); /* find an existing plex with this name */
            if (namedplexno >= 0) {                         /* plex exists already, */
                if (PLEX[namedplexno].state == plex_referenced) { /* we've been told about this one */
                    if (parameter > 2)                      /* we've done other things first, */
                        throw_rude_remark(EINVAL,
                            "plex %s: name parameter must come first\n", /* no go */
                            token[parameter]);
                    else {
                        int i;
                        struct volume *vol;                 /* for tidying up dangling references */

                        *plex = PLEX[namedplexno];          /* get the info */
                        PLEX[namedplexno].state = plex_unallocated; /* and deallocate the other one */
                        vol = &VOL[plex->volno];            /* point to the volume */
                        for (i = 0; i < MAXPLEX; i++) {     /* for each plex */
                            if (vol->plex[i] == namedplexno)
                                vol->plex[i] = plexno;      /* bend the pointer */
                        }
                    }
                    break;                                  /* use this one */
                }
                if (update)                                 /* are we updating? */
                    return;                                 /* yes: that's OK, just return */
                else
                    throw_rude_remark(EINVAL, "Duplicate plex %s", token[parameter]);
            } else
                bcopy(token[parameter],                     /* put in the name */
                    plex->name,
                    min(MAXPLEXNAME, strlen(token[parameter])));
            break;

        case kw_detached:
            detached = 1;
            break;

        case kw_org:                                        /* plex organization */
            switch (get_keyword(token[++parameter], &keyword_set)) {
            case kw_concat:
                plex->organization = plex_concat;
                break;

            case kw_striped:
                {
                    int stripesize = sizespec(token[++parameter]);

                    plex->organization = plex_striped;
                    if (stripesize % DEV_BSIZE != 0)        /* not a multiple of block size, */
                        throw_rude_remark(EINVAL, "plex %s: stripe size %d not a multiple of sector size",
                            plex->name,
                            stripesize);
                    else
                        plex->stripesize = stripesize / DEV_BSIZE;
                    break;
                }

            case kw_raid4:
                {
                    int stripesize = sizespec(token[++parameter]);

                    plex->organization = plex_raid4;
                    if (stripesize % DEV_BSIZE != 0)        /* not a multiple of block size, */
                        throw_rude_remark(EINVAL, "plex %s: stripe size %d not a multiple of sector size",
                            plex->name,
                            stripesize);
                    else
                        plex->stripesize = stripesize / DEV_BSIZE;
                    break;
                }

            case kw_raid5:
                {
                    int stripesize = sizespec(token[++parameter]);

                    plex->organization = plex_raid5;
                    if (stripesize % DEV_BSIZE != 0)        /* not a multiple of block size, */
                        throw_rude_remark(EINVAL, "plex %s: stripe size %d not a multiple of sector size",
                            plex->name,
                            stripesize);
                    else
                        plex->stripesize = stripesize / DEV_BSIZE;
                    break;
                }

            default:
                throw_rude_remark(EINVAL, "Invalid plex organization");
            }
            if (isstriped(plex)
                && (plex->stripesize == 0))                 /* didn't specify a valid stripe size */
                throw_rude_remark(EINVAL, "Need a stripe size parameter");
            break;

        case kw_volume:
            plex->volno = find_volume(token[++parameter], 1); /* insert a pointer to the volume */
            break;

        case kw_sd:                                         /* add a subdisk */
            {
                int sdno;

                sdno = find_subdisk(token[++parameter], 1); /* find a subdisk */
                SD[sdno].plexoffset = sizespec(token[++parameter]); /* get the offset */
                give_sd_to_plex(plexno, sdno);              /* and insert it there */
                break;
            }

        case kw_state:
            parameter++;                                    /* skip the keyword */
            if (vinum_conf.flags & VF_READING_CONFIG)
                state = PlexState(token[parameter]);        /* set the state */
            break;

        default:
            throw_rude_remark(EINVAL, "plex %s, invalid keyword: %s",
                plex->name,
                token[parameter]);
        }
    }

    if (plex->organization == plex_disorg)
        throw_rude_remark(EINVAL, "No plex organization specified");

    if ((plex->volno < 0)                                   /* we don't have a volume */
    &&(!detached))                                          /* and we wouldn't object */
        plex->volno = current_volume;

    if (plex->volno >= 0)
        pindex = give_plex_to_volume(plex->volno, plexno);  /* Now tell the volume that it has this plex */

    /* Does the plex have a name?  If not, give it one */
    if (plex->name[0] == '\0') {                            /* no name */
        char plexsuffix[8];                                 /* form plex name suffix here */
        /* Do we have a volume name? */
        if (plex->volno >= 0)                               /* we have a volume */
            strcpy(plex->name,                              /* take it from there */
                VOL[plex->volno].name);
        else                                                /* no way */
            throw_rude_remark(EINVAL, "Unnamed plex is not associated with a volume");
        ksprintf(plexsuffix, ".p%d", pindex);               /* form the suffix */
        strcat(plex->name, plexsuffix);                     /* and add it to the name */
    }
    if (isstriped(plex)) {
        plex->lock = (struct rangelock *)
            Malloc(PLEX_LOCKS * sizeof(struct rangelock));
        CHECKALLOC(plex->lock, "vinum: Can't allocate lock table\n");
        bzero((char *) plex->lock, PLEX_LOCKS * sizeof(struct rangelock));
    }
    /* Note the last plex we configured */
    current_plex = plexno;
    plex->state = state;                                    /* set whatever state we chose */
    vinum_conf.plexes_used++;                               /* one more in use */
}

/*
 * Handle a volume definition.
 * If we find an error, print a message, deallocate the nascent volume, and return
 */
void
config_volume(int update)
{
    int parameter;
    int volno;
    struct volume *vol;                                     /* collect volume info here */
    int i;

    if (tokens < 2)                                         /* not enough tokens */
        throw_rude_remark(EINVAL, "Volume has no name");
    current_volume = -1;                                    /* forget the previous volume */
    volno = find_volume(token[1], 1);                       /* allocate a volume to initialize */
    vol = &VOL[volno];                                      /* and get a pointer */
    if (update && ((vol->flags & VF_CREATED) == 0))         /* this volume exists already */
        return;                                             /* don't do anything */
    vol->flags &= ~VF_CREATED;                              /* it exists now */

    for (parameter = 2; parameter < tokens; parameter++) {  /* look at all tokens */
        switch (get_keyword(token[parameter], &keyword_set)) {
        case kw_plex:
            {
                int plexno;                                 /* index of this plex */
                int myplexno;                               /* and index if it's already ours */

                plexno = find_plex(token[++parameter], 1);  /* find a plex */
                if (plexno < 0)                             /* couldn't */
                    break;                                  /* we've already had an error message */
                myplexno = my_plex(volno, plexno);          /* does it already belong to us? */
                if (myplexno > 0)                           /* yes, shouldn't get it again */
                    throw_rude_remark(EINVAL,
                        "Plex %s already belongs to volume %s",
                        token[parameter],
                        vol->name);
                else if (vol->plexes + 1 > 8)               /* another entry */
                    throw_rude_remark(EINVAL,
                        "Too many plexes for volume %s",
                        vol->name);
                vol->plex[vol->plexes] = plexno;
                vol->plexes++;
                PLEX[plexno].state = plex_referenced;       /* we know something about it */
                PLEX[plexno].volno = volno;                 /* and this volume references it */
            }
            break;

        case kw_readpol:
            switch (get_keyword(token[++parameter], &keyword_set)) { /* decide what to do */
            case kw_round:
                vol->preferred_plex = ROUND_ROBIN_READPOL;  /* default */
                break;

            case kw_prefer:
                {
                    int myplexno;                           /* index of this plex */

                    myplexno = find_plex(token[++parameter], 1); /* find a plex */
                    if (myplexno < 0)                       /* couldn't */
                        break;                              /* we've already had an error message */
                    myplexno = my_plex(volno, myplexno);    /* does it already belong to us? */
                    if (myplexno > 0)                       /* yes */
                        vol->preferred_plex = myplexno;     /* just note the index */
                    else if (++vol->plexes > 8)             /* another entry */
                        throw_rude_remark(EINVAL, "Too many plexes");
                    else {                                  /* space for the new plex */
                        vol->plex[vol->plexes - 1] = myplexno; /* add it to our list */
                        vol->preferred_plex = vol->plexes - 1; /* and note the index */
                    }
                }
                break;

            default:
                throw_rude_remark(EINVAL, "Invalid read policy");
            }

        case kw_setupstate:
            vol->flags |= VF_CONFIG_SETUPSTATE;             /* set the volume up later on */
            break;

        case kw_state:
            parameter++;                                    /* skip the keyword */
            if (vinum_conf.flags & VF_READING_CONFIG)
                vol->state = VolState(token[parameter]);    /* set the state */
            break;

            /*
             * XXX experimental ideas.  These are not
             * documented, and will not be until I
             * decide they're worth keeping
             */
        case kw_writethrough:                               /* set writethrough mode */
            vol->flags |= VF_WRITETHROUGH;
            break;

        case kw_writeback:                                  /* set writeback mode */
            vol->flags &= ~VF_WRITETHROUGH;
            break;

        case kw_raw:
            vol->flags |= VF_RAW;                           /* raw volume (no label) */
            break;

        default:
            throw_rude_remark(EINVAL, "volume %s, invalid keyword: %s",
                vol->name,
                token[parameter]);
        }
    }
    current_volume = volno;                                 /* note last referred volume */
    vol->volno = volno;                                     /* also note in volume */

    /*
     * Before we can actually use the volume, we need
     * a volume label.  We could start to fake one here,
     * but it will be a lot easier when we have some
     * to copy from the drives, so defer it until we
     * set up the configuration. XXX
     */
    if (vol->state == volume_unallocated)
        vol->state = volume_down;                           /* now ready to bring up at the end */

    /* Find out how big our volume is */
    for (i = 0; i < vol->plexes; i++)
        vol->size = max(vol->size, PLEX[vol->plex[i]].length);
    vinum_conf.volumes_used++;                              /* one more in use */
}

/*
 * Parse a config entry.  CARE!  This destroys the original contents of the
 * config entry, which we don't really need after this.  More specifically, it
 * places \0 characters at the end of each token.
 *
 * Return 0 if all is well, otherwise EINVAL for invalid keyword,
 * or ENOENT if 'read' command doesn't find any drives.
 */
int
parse_config(char *cptr, struct keywordset *keyset, int update)
{
    int status;

    status = 0;                                             /* until proven otherwise */
    tokens = tokenize(cptr, token);                         /* chop up into tokens */

    if (tokens <= 0)                                        /* screwed up or empty line */
        return tokens;                                      /* give up */

    if (token[0][0] == '#')                                 /* comment line */
        return 0;

    switch (get_keyword(token[0], keyset)) {                /* decide what to do */
    case kw_read:                                           /* read config from a specified drive */
        status = vinum_scandisk(&token[1], tokens - 1);     /* read the config from disk */
        break;

    case kw_drive:
        config_drive(update);
        break;

    case kw_subdisk:
        config_subdisk(update);
        break;

    case kw_plex:
        config_plex(update);
        break;

    case kw_volume:
        config_volume(update);
        break;

        /* Anything else is invalid in this context */
    default:
        throw_rude_remark(EINVAL,                           /* should we die? */
            "Invalid configuration information: %s",
            token[0]);
    }
    return status;
}

/*
 * parse a line handed in from userland via ioctl.
 * This differs only by the error reporting mechanism:
 * we return the error indication in the reply to the
 * ioctl, so we need to set a global static pointer in
 * this file.  This technique works because we have
 * ensured that configuration is performed in a single-
 * threaded manner
 */
int
parse_user_config(char *cptr, struct keywordset *keyset)
{
    int status;

    ioctl_reply = (struct _ioctl_reply *) cptr;
    status = parse_config(cptr, keyset, 0);
    if (status == ENOENT)                                   /* from scandisk, but it can't tell us */
        strcpy(ioctl_reply->msg, "no drives found");
    ioctl_reply = NULL;                                     /* don't do this again */
    return status;
}

/* Remove an object */
void
remove(struct vinum_ioctl_msg *msg)
{
    struct vinum_ioctl_msg message = *msg;                  /* make a copy to hand on */

    ioctl_reply = (struct _ioctl_reply *) msg;              /* reinstate the address to reply to */
    ioctl_reply->error = 0;                                 /* no error, */
    ioctl_reply->msg[0] = '\0';                             /* no message */

    switch (message.type) {
    case drive_object:
        remove_drive_entry(message.index, message.force);
        updateconfig(0);
        return;

    case sd_object:
        remove_sd_entry(message.index, message.force, message.recurse);
        updateconfig(0);
        return;

    case plex_object:
        remove_plex_entry(message.index, message.force, message.recurse);
        updateconfig(0);
        return;

    case volume_object:
        remove_volume_entry(message.index, message.force, message.recurse);
        updateconfig(0);
        return;

    default:
        ioctl_reply->error = EINVAL;
        strcpy(ioctl_reply->msg, "Invalid object type");
    }
}

/* Remove a drive.  */
void
remove_drive_entry(int driveno, int force)
{
    struct drive *drive = &DRIVE[driveno];
    int sdno;

    if ((driveno > vinum_conf.drives_allocated)             /* not a valid drive */
    ||(drive->state == drive_unallocated)) {                /* or nothing there */
        ioctl_reply->error = EINVAL;
        strcpy(ioctl_reply->msg, "No such drive");
    } else if (drive->opencount > 0) {                      /* we have subdisks */
        if (force) {                                        /* do it at any cost */
            for (sdno = 0; sdno < vinum_conf.subdisks_allocated; sdno++) {
                if ((SD[sdno].state != sd_unallocated)      /* subdisk is allocated */
                &&(SD[sdno].driveno == driveno))            /* and it belongs to this drive */
                    remove_sd_entry(sdno, force, 0);
            }
            remove_drive(driveno);                          /* now remove it */
            vinum_conf.drives_used--;                       /* one less drive */
        } else
            ioctl_reply->error = EBUSY;                     /* can't do that */
    } else {
        remove_drive(driveno);                              /* just remove it */
        vinum_conf.drives_used--;                           /* one less drive */
    }
}

/* remove a subdisk */
void
remove_sd_entry(int sdno, int force, int recurse)
{
    struct sd *sd = &SD[sdno];

    if ((sdno > vinum_conf.subdisks_allocated)              /* not a valid sd */
    ||(sd->state == sd_unallocated)) {                      /* or nothing there */
        ioctl_reply->error = EINVAL;
        strcpy(ioctl_reply->msg, "No such subdisk");
    } else if (sd->flags & VF_OPEN) {                       /* we're open */
        ioctl_reply->error = EBUSY;                         /* no getting around that */
        return;
    } else if (sd->plexno >= 0) {                           /* we have a plex */
        if (force) {                                        /* do it at any cost */
            struct plex *plex = &PLEX[sd->plexno];          /* point to our plex */
            int mysdno;

            for (mysdno = 0;                                /* look for ourselves */
                mysdno < plex->subdisks && &SD[plex->sdnos[mysdno]] != sd;
                mysdno++);
            if (mysdno == plex->subdisks)                   /* didn't find it */
                log(LOG_ERR,
                    "Error removing subdisk %s: not found in plex %s\n",
                    SD[mysdno].name,
                    plex->name);
            else {                                          /* remove the subdisk from plex */
                if (mysdno < (plex->subdisks - 1))          /* not the last subdisk */
                    bcopy(&plex->sdnos[mysdno + 1],
                        &plex->sdnos[mysdno],
                        (plex->subdisks - 1 - mysdno) * sizeof(int));
                plex->subdisks--;
                sd->plexno = -1;                            /* disown the subdisk */
            }

            /*
             * Removing a subdisk from a striped or
             * RAID-4 or RAID-5 plex really tears the
             * hell out of the structure, and it needs
             * to be reinitialized.
             */
            if (plex->organization != plex_concat)          /* not concatenated, */
                set_plex_state(plex->plexno, plex_faulty, setstate_force); /* need to reinitialize */
            log(LOG_INFO, "vinum: removing %s\n", sd->name);
            free_sd(sdno);
        } else
            ioctl_reply->error = EBUSY;                     /* can't do that */
    } else {
        log(LOG_INFO, "vinum: removing %s\n", sd->name);
        free_sd(sdno);
    }
}

/* remove a plex */
void
remove_plex_entry(int plexno, int force, int recurse)
{
    struct plex *plex = &PLEX[plexno];
    int sdno;

    if ((plexno > vinum_conf.plexes_allocated)              /* not a valid plex */
    ||(plex->state == plex_unallocated)) {                  /* or nothing there */
        ioctl_reply->error = EINVAL;
        strcpy(ioctl_reply->msg, "No such plex");
    } else if (plex->flags & VF_OPEN) {                     /* we're open */
        ioctl_reply->error = EBUSY;                         /* no getting around that */
        return;
    }
    if (plex->subdisks) {
        if (force) {                                        /* do it anyway */
            if (recurse) {                                  /* remove all below */
                int sds = plex->subdisks;
                for (sdno = 0; sdno < sds; sdno++)
                    free_sd(plex->sdnos[sdno]);             /* free all subdisks */
            } else {                                        /* just tear them out */
                int sds = plex->subdisks;
                for (sdno = 0; sdno < sds; sdno++)
                    SD[plex->sdnos[sdno]].plexno = -1;      /* no plex any more */
            }
        } else {                                            /* can't do it without force */
            ioctl_reply->error = EBUSY;                     /* can't do that */
            return;
        }
    }
    if (plex->volno >= 0) {                                 /* we are part of a volume */
        if (force) {                                        /* do it at any cost */
            struct volume *vol = &VOL[plex->volno];
            int myplexno;

            for (myplexno = 0; myplexno < vol->plexes; myplexno++)
                if (vol->plex[myplexno] == plexno)          /* found it */
                    break;
            if (myplexno == vol->plexes)                    /* didn't find it.  Huh? */
                log(LOG_ERR,
                    "Error removing plex %s: not found in volume %s\n",
                    plex->name,
                    vol->name);
            if (myplexno < (vol->plexes - 1))               /* not the last plex in the list */
                bcopy(&vol->plex[myplexno + 1],
                    &vol->plex[myplexno],
                    vol->plexes - 1 - myplexno);
            vol->plexes--;
        } else {
            ioctl_reply->error = EBUSY;                     /* can't do that */
            return;
        }
    }
    log(LOG_INFO, "vinum: removing %s\n", plex->name);
    free_plex(plexno);
    vinum_conf.plexes_used--;                               /* one less plex */
}

/* remove a volume */
void
remove_volume_entry(int volno, int force, int recurse)
{
    struct volume *vol = &VOL[volno];
    int plexno;

    if ((volno > vinum_conf.volumes_allocated)              /* not a valid volume */
    ||(vol->state == volume_unallocated)) {                 /* or nothing there */
        ioctl_reply->error = EINVAL;
        strcpy(ioctl_reply->msg, "No such volume");
    } else if (vol->flags & VF_OPEN)                        /* we're open */
        ioctl_reply->error = EBUSY;                         /* no getting around that */
    else if (vol->plexes) {
        if (recurse && force) {                             /* remove all below */
            int plexes = vol->plexes;

/*       for (plexno = plexes - 1; plexno >= 0; plexno--) */
            for (plexno = 0; plexno < plexes; plexno++)
                remove_plex_entry(vol->plex[plexno], force, recurse);
            log(LOG_INFO, "vinum: removing %s\n", vol->name);
            free_volume(volno);
            vinum_conf.volumes_used--;                      /* one less volume */
        } else
            ioctl_reply->error = EBUSY;                     /* can't do that */
    } else {
        log(LOG_INFO, "vinum: removing %s\n", vol->name);
        free_volume(volno);
        vinum_conf.volumes_used--;                          /* one less volume */
    }
}

/* Currently called only from ioctl */
void
update_sd_config(int sdno, int diskconfig)
{
    if (!diskconfig)
        set_sd_state(sdno, sd_up, setstate_configuring);
    SD[sdno].flags &= ~VF_NEWBORN;
}

void
update_plex_config(int plexno, int diskconfig)
{
    u_int64_t size;
    int sdno;
    struct plex *plex = &PLEX[plexno];
    enum plexstate state = plex_up;                         /* state we want the plex in */
    int remainder;                                          /* size of fractional stripe at end */
    int added_plex;                                         /* set if we add a plex to a volume */
    int required_sds;                                       /* number of subdisks we need */
    struct sd *sd;
    struct volume *vol;
    int data_sds = 0;                                       /* number of sds carrying data */

    if (plex->state < plex_init)                            /* not a real plex, */
        return;
    added_plex = 0;
    if (plex->volno >= 0) {                                 /* we have a volume */
        vol = &VOL[plex->volno];

        /*
         * If we're newly born,
         * and the volume isn't,
         * and it has other plexes,
         * and we didn't read this mess from disk,
         * we were added later.
         */
        if ((plex->flags & VF_NEWBORN)
            && ((vol->flags & VF_NEWBORN) == 0)
            && (vol->plexes > 0)
            && (diskconfig == 0)) {
            added_plex = 1;
            state = plex_down;                              /* so take ourselves down */
        }
    }
    /*
     * Check that our subdisks make sense.  For
     * striped, RAID-4 and RAID-5 plexes, we need at
     * least two subdisks, and they must all be the
     * same size.
     */
    if (plex->organization == plex_striped) {
        data_sds = plex->subdisks;
        required_sds = 2;
    } else if (isparity(plex)) {                            /* RAID 4 or 5 */
        data_sds = plex->subdisks - 1;
        required_sds = 3;
    } else
        required_sds = 0;
    if (required_sds > 0) {                                 /* striped, RAID-4 or RAID-5 */
        if (plex->subdisks < required_sds) {
            log(LOG_ERR,
                "vinum: plex %s does not have at least %d subdisks\n",
                plex->name,
                required_sds);
            state = plex_faulty;
        }
        /*
         * Now see if the plex size is a multiple of
         * the stripe size.  If not, trim off the end
         * of each subdisk and return it to the drive.
         */
        if (plex->length > 0) {
            if (data_sds > 0) {
                if (plex->stripesize > 0) {
                    remainder = (int) (plex->length         /* are we exact? */
                        % ((u_int64_t) plex->stripesize * data_sds));
                    if (remainder) {                        /* no */
                        log(LOG_INFO, "vinum: removing %d blocks of partial stripe at the end of %s\n",
                            remainder,
                            plex->name);
                        plex->length -= remainder;          /* shorten the plex */
                        remainder /= data_sds;              /* spread the remainder amongst the sds */
                        for (sdno = 0; sdno < plex->subdisks; sdno++) {
                            sd = &SD[plex->sdnos[sdno]];    /* point to the subdisk */
                            return_drive_space(sd->driveno, /* return the space */
                                sd->driveoffset + sd->sectors - remainder,
                                remainder);
                            sd->sectors -= remainder;       /* and shorten it */
                        }
                    }
                } else                                      /* no data sds, */
                    plex->length = 0;                       /* reset length */
            }
        }
    }
    size = 0;
    for (sdno = 0; sdno < plex->subdisks; sdno++) {
        sd = &SD[plex->sdnos[sdno]];
        if (isstriped(plex)
            && (sdno > 0)
            && (sd->sectors != SD[plex->sdnos[sdno - 1]].sectors)) {
            log(LOG_ERR, "vinum: %s must have equal sized subdisks\n", plex->name);
            state = plex_down;
        }
        size += sd->sectors;
        if (added_plex)                                     /* we were added later */
            sd->state = sd_stale;                           /* stale until proven otherwise */
    }

    if (plex->subdisks) {                                   /* plex has subdisks, calculate size */
        /*
         * XXX We shouldn't need to calculate the size any
         * more.  Check this some time
         */
        if (isparity(plex))
            size = size / plex->subdisks * (plex->subdisks - 1); /* less space for RAID-4 and RAID-5 */
        if (plex->length != size)
            log(LOG_INFO,
                "Correcting length of %s: was %lld, is %lld\n",
                plex->name,
                (long long) plex->length,
                (long long) size);
        plex->length = size;
    } else {                                                /* no subdisks, */
        plex->length = 0;                                   /* no size */
        state = plex_down;                                  /* take it down */
    }
    update_plex_state(plexno);                              /* set the state */
    plex->flags &= ~VF_NEWBORN;
}

void
update_volume_config(int volno, int diskconfig)
{
    struct volume *vol = &VOL[volno];
    struct plex *plex;
    int plexno;

    if (vol->state != volume_unallocated)
        /*
         * Recalculate the size of the volume,
         * which might change if the original
         * plexes were not a multiple of the
         * stripe size.
         */
    {
        vol->size = 0;
        for (plexno = 0; plexno < vol->plexes; plexno++) {
            plex = &PLEX[vol->plex[plexno]];
            vol->size = max(plex->length, vol->size);       /* maximum size */
            plex->volplexno = plexno;                       /* note it in the plex */
        }
    }
    vol->flags &= ~VF_NEWBORN;                              /* no longer newly born */
}

/*
 * Update the global configuration.
 * diskconfig is != 0 if we're reading in a config
 * from disk.  In this case, we don't try to
 * bring the devices up, though we will bring
 * them down if there's some error which got
 * missed when writing to disk.
 */
void
updateconfig(int diskconfig)
{
    int plexno;
    int volno;

    for (plexno = 0; plexno < vinum_conf.plexes_allocated; plexno++)
        update_plex_config(plexno, diskconfig);

    for (volno = 0; volno < vinum_conf.volumes_allocated; volno++) {
        if (VOL[volno].state > volume_uninit) {
            VOL[volno].flags &= ~VF_CONFIG_SETUPSTATE;      /* no more setupstate */
            update_volume_state(volno);
            update_volume_config(volno, diskconfig);
        }
    }
    save_config();
}

/*
 * Start manual changes to the configuration and lock out
 * others who may wish to do so.
 * XXX why do we need this and lock_config too?
 */
int
start_config(int force)
{
    int error;

    current_drive = -1;                                     /* note the last drive we mention, for
                                                            * some defaults */
    current_plex = -1;                                      /* and the same for the last plex */
    current_volume = -1;                                    /* and the last volume */
    while ((vinum_conf.flags & VF_CONFIGURING) != 0) {
        vinum_conf.flags |= VF_WILL_CONFIGURE;
        if ((error = tsleep(&vinum_conf, PCATCH, "vincfg", 0)) != 0)
            return error;
    }
    /*
     * We need two flags here: VF_CONFIGURING
     * tells other processes to hold off (this
     * function), and VF_CONFIG_INCOMPLETE
     * tells the state change routines not to
     * propagate incrememntal state changes
     */
    vinum_conf.flags |= VF_CONFIGURING | VF_CONFIG_INCOMPLETE;
    if (force)
        vinum_conf.flags |= VF_FORCECONFIG;                 /* overwrite differently named drives */
    current_drive = -1;                                     /* reset the defaults */
    current_plex = -1;                                      /* and the same for the last plex */
    current_volume = -1;                                    /* and the last volme */
    return 0;
}

/*
 * Update the config if update is 1, and unlock
 * it.  We won't update the configuration if we
 * are called in a recursive loop via throw_rude_remark.
 */
void
finish_config(int update)
{
    /* we've finished our config */
    vinum_conf.flags &= ~(VF_CONFIG_INCOMPLETE | VF_READING_CONFIG | VF_FORCECONFIG);
    if (update)
        updateconfig(0);                                    /* so update things */
    else
        updateconfig(1);                                    /* do some updates only */
    vinum_conf.flags &= ~VF_CONFIGURING;                    /* and now other people can take a turn */
    if ((vinum_conf.flags & VF_WILL_CONFIGURE) != 0) {
        vinum_conf.flags &= ~VF_WILL_CONFIGURE;
        wakeup_one(&vinum_conf);
    }
}
/* Local Variables: */
/* fill-column: 50 */
/* End: */