vinumconfig.c

基于组件方式开发操作系统的OSKIT源代码

    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;

    /* 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 */
    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 */

    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++;
	    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 */
		break;

	    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:
	    checkdiskconfig(token[++parameter]);	    /* must be reading from disk */
	    drive->state = DriveState(token[parameter]);    /* set the state */
	    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 */
}

/*
 * 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 */

    sdno = get_empty_sd();				    /* allocate an SD to initialize */
    sd = &SD[sdno];					    /* and get a pointer */
    sd->sectors = -1;					    /* to distinguish from 0 */

    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, 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, 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:
	    checkdiskconfig(token[++parameter]);	    /* must be reading from disk */
	    state = SdState(token[parameter]);		    /* set the state */
	    break;

	default:
	    throw_rude_remark(EINVAL, "sd %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.
     */