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/*
* mdadm - manage Linux "md" devices aka RAID arrays.
*
* Copyright (C) 2001-2002 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 "mdadm.h"
#include "md_p.h"
#include <ctype.h>
void make_parts(char *dev, int cnt)
{
/* make 'cnt' partition devices for 'dev'
* We use the major/minor from dev and add 1..cnt
* If dev ends with a digit, we add "p%d" else "%d"
* If the name exists, we use it's owner/mode,
* else that of dev
*/
struct stat stb;
int major, minor;
int i;
int nlen = strlen(dev) + 20;
char *name = malloc(nlen);
int dig = isdigit(dev[strlen(dev)-1]);
if (stat(dev, &stb)!= 0)
return;
if (!S_ISBLK(stb.st_mode))
return;
major = major(stb.st_rdev);
minor = minor(stb.st_rdev);
for (i=1; i <= cnt ; i++) {
struct stat stb2;
snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i);
if (stat(name, &stb2)==0) {
if (!S_ISBLK(stb2.st_mode))
continue;
if (stb2.st_rdev == makedev(major, minor+i))
continue;
unlink(name);
} else {
stb2 = stb;
}
if (mknod(name, S_IFBLK | 0600, makedev(major, minor+i)))
perror("mknod");
if (chown(name, stb2.st_uid, stb2.st_gid))
perror("chown");
if (chmod(name, stb2.st_mode & 07777))
perror("chmod");
stat(name, &stb2);
add_dev(name, &stb2, 0, NULL);
}
}
/*
* Open a given md device, and check that it really is one.
* If 'autof' is given, then we need to create, or recreate, the md device.
* If the name already exists, and is not a block device, we fail.
* If it exists and is not an md device, is not the right type (partitioned or not),
* or is currently in-use, we remove the device, but remember the owner and mode.
* If it now doesn't exist, we find a new md array and create the device.
* Default ownership is user=0, group=0 perm=0600
*/
int open_mddev(char *dev, int autof)
{
int mdfd;
struct stat stb;
int major = MD_MAJOR;
int minor = 0;
int must_remove = 0;
struct mdstat_ent *mdlist;
int num;
if (autof) {
/* autof is set, so we need to check that the name is ok,
* and possibly create one if not
*/
if (autof == -2 && !is_standard(dev, NULL)) {
fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\n", dev);
return -1;
}
stb.st_mode = 0;
if (stat(dev, &stb)==0 && ! S_ISBLK(stb.st_mode)) {
fprintf(stderr, Name ": %s is not a block device.\n",
dev);
return -1;
}
/* check major number is correct */
if (autof>0)
major = get_mdp_major();
if (stb.st_mode && major(stb.st_rdev) != major)
must_remove = 1;
if (stb.st_mode && !must_remove) {
mdu_array_info_t array;
/* looks ok, see if it is available */
mdfd = open(dev, O_RDWR, 0);
if (mdfd < 0) {
fprintf(stderr, Name ": error opening %s: %s\n",
dev, strerror(errno));
return -1;
} else if (md_get_version(mdfd) <= 0) {
fprintf(stderr, Name ": %s does not appear to be an md device\n",
dev);
close(mdfd);
return -1;
}
if (ioctl(mdfd, GET_ARRAY_INFO, &array)==0) {
/* already active */
must_remove = 1;
close(mdfd);
} else {
if (autof > 0)
make_parts(dev, autof);
return mdfd;
}
}
/* Ok, need to find a minor that is not in use.
* If the device name is in a 'standard' format,
* intuit the minor from that, else
* easiest to read /proc/mdstat, and hunt through for
* an unused number
*/
switch(is_standard(dev, &num)) {
case -1: /* non partitioned */
if (autof > 0) {
fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
return -1;
}
minor = num;
num = -1-num;
break;
case 1: /* partitioned */
if (autof == -1) {
fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
return -1;
}
minor = num << MdpMinorShift;
major = get_mdp_major();
break;
case 0: /* not standard, pick an unused number */
mdlist = mdstat_read(0, 0);
for (num= (autof>0)?-1:0 ; ; num+= (autof>2)?-1:1) {
struct mdstat_ent *me;
for (me=mdlist; me; me=me->next)
if (me->devnum == num)
break;
if (!me) {
/* doesn't exist if mdstat.
* make sure it is new to /dev too
*/
char *dn;
if (autof > 0)
minor = (-1-num) << MdpMinorShift;
else
minor = num;
dn = map_dev(major,minor, 0);
if (dn==NULL || is_standard(dn, NULL)) {
/* this number only used by a 'standard' name,
* so it is safe to use
*/
break;
}
}
}
}
/* major and minor have been chosen */
/* If it was a 'standard' name and it is in-use, then
* the device could already be correct
*/
if (stb.st_mode && major(stb.st_rdev) == major &&
minor(stb.st_rdev) == minor)
;
else {
if (major(makedev(major,minor)) != major ||
minor(makedev(major,minor)) != minor) {
fprintf(stderr, Name ": Need newer C library to use more than 4 partitionable md devices, sorry\n");
return -1;
}
if (must_remove)
unlink(dev);
if (mknod(dev, S_IFBLK|0600, makedev(major, minor))!= 0) {
fprintf(stderr, Name ": failed to create %s\n", dev);
return -1;
}
if (must_remove) {
if (chown(dev, stb.st_uid, stb.st_gid))
perror("chown");
if (chmod(dev, stb.st_mode & 07777))
perror("chmod");
}
stat(dev, &stb);
add_dev(dev, &stb, 0, NULL);
make_parts(dev,autof);
}
}
mdfd = open(dev, O_RDWR, 0);
if (mdfd < 0)
fprintf(stderr, Name ": error opening %s: %s\n",
dev, strerror(errno));
else if (md_get_version(mdfd) <= 0) {
fprintf(stderr, Name ": %s does not appear to be an md device\n",
dev);
close(mdfd);
mdfd = -1;
}
return mdfd;
}
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