mdadm/Build.c

/*
 * mdctl - manage Linux "md" devices aka RAID arrays.
 *
 * Copyright (C) 2001 Neil Brown <neilb@cse.unsw.edu.au>
 *
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *    Author: Neil Brown
 *    Email: <neilb@cse.unsw.edu.au>
 *    Paper: Neil Brown
 *           School of Computer Science and Engineering
 *           The University of New South Wales
 *           Sydney, 2052
 *           Australia
 */

#include "mdctl.h"

#define REGISTER_DEV 		_IO (MD_MAJOR, 1)
#define START_MD     		_IO (MD_MAJOR, 2)
#define STOP_MD      		_IO (MD_MAJOR, 3)

int Build(char *mddev, int mdfd, int chunk, int level,
	  int raiddisks,
	  int subdevs, char *subdev[])
{
	/* Build a linear or raid0 arrays without superblocks
	 * We cannot really do any checks, we just do it.
	 * For md_version < 0.90.0, we call REGISTER_DEV
	 * with the device numbers, and then
	 * START_MD giving the "geometry"
	 * geometry is 0xpp00cc
	 * where pp is personality: 1==linear, 2=raid0
	 * cc = chunk size factor: 0==4k, 1==8k etc.
	 *
	 * For md_version >= 0.90.0 we call
	 * SET_ARRAY_INFO,  ADD_NEW_DISK, RUN_ARRAY
	 *
	 */
	int i;
	int vers;
	struct stat stb;
	if (raiddisks != subdevs) {
		fprintf(stderr, Name ": requested %d devices in array but listed %d\n",
			raiddisks, subdevs);
		return 1;
	}

	/* scan all devices, make sure they really are block devices */
	for (i=0; i<subdevs; i++) {
		if (stat(subdev[i], &stb)) {
			fprintf(stderr, Name ": Cannot find %s: %s\n",
				subdev[i], strerror(errno));
			return 1;
		}
		if ((stb.st_mode & S_IFMT) != S_IFBLK) {
			fprintf(stderr, Name ": %s is not a block device.\n",
				subdev[i]);
			return 1;
		}
	}

	vers = md_get_version(mdfd);
	
	/* looks Ok, go for it */
	if (vers >= 90000) {
		mdu_array_info_t array;
		array.level = level;
		array.size = 0;
		array.nr_disks = raiddisks;
		array.raid_disks = raiddisks;
		array.md_minor = 0;
		if (fstat(mdfd, &stb)==0)
			array.md_minor = MINOR(stb.st_rdev);
		array.not_persistent = 0;
		array.state = 0; /* not clean, but no errors */
		array.active_disks = raiddisks;
		array.working_disks = raiddisks;
		array.spare_disks = 0;
		array.failed_disks = 0;
		array.chunk_size = chunk*1024;
		if (ioctl(mdfd, SET_ARRAY_INFO, &array)) {
			fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
				mddev, strerror(errno));
			return 1;
		}
	}
	/* now add the devices */
	for (i=0; i<subdevs; i++) {
		if (stat(subdev[i], &stb)) {
			fprintf(stderr, Name ": Wierd: %s has disappeared.\n",
				subdev[i]);
			goto abort;
		}
		if ((stb.st_rdev & S_IFMT)!= S_IFBLK) {
			fprintf(stderr, Name ": Wierd: %s is no longer a block device.\n",
				subdev[i]);
			goto abort;
		}
		if (vers> 90000) {
			mdu_disk_info_t disk;
			disk.number = i;
			disk.raid_disk = i;
			disk.state = 6;
			disk.major = MAJOR(stb.st_rdev);
			disk.minor = MINOR(stb.st_rdev);
			if (ioctl(mdfd, ADD_NEW_DISK, &disk)) {
				fprintf(stderr, Name ": ADD_NEW_DISK failed for %s: %s\n",
					subdev[i], strerror(errno));
				goto abort;
			}
		} else {
			if (ioctl(mdfd, REGISTER_DEV, &stb.st_rdev)) {
				fprintf(stderr, Name ": REGISTER_DEV failed for %s.\n",
					subdev[i], strerror(errno));
				goto abort;
			}
		}
	}
	/* now to start it */
	if (vers > 90000) {
		mdu_param_t param; /* not used by syscall */
		if (ioctl(mdfd, RUN_ARRAY, param)) {
			fprintf(stderr, Name ": RUN_ARRAY failed: %s\n",
				strerror(errno));
			goto abort;
		}
	} else {
		int arg;
		arg=0;
		while (chunk > 4096) {
			arg++;
			chunk >>= 1;
		}
		if (level == 0)
			chunk |= 0x20000;
		else 	chunk |= 0x10000;
		if (ioctl(mdfd, START_MD, arg)) {
			fprintf(stderr, Name ": START_MD failed: %s\n",
				strerror(errno));
			goto abort;
		}
	}
	fprintf(stderr, Name ": array %s built and started.\n",
		mddev);
	return 0;

 abort:
	if (vers > 900000)
	    ioctl(mdfd, STOP_ARRAY, 0);
	else
	    ioctl(mdfd, STOP_MD, 0);
	return 1;
		
}