+ /* 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;
+ char *name = malloc(strlen(dev) + 20);
+ 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;
+ sprintf(name, "%s%s%d", dev, dig?"_p":"", i);
+ if (stat(name, &stb2)==0) {
+ if (!S_ISBLK(stb2.st_mode))
+ continue;
+ if (stb2.st_rdev == MKDEV(major, minor+i))
+ continue;
+ unlink(name);
+ } else {
+ stb2 = stb;
+ }
+ mknod(name, S_IFBLK | 0600, MKDEV(major, minor+i));
+ chown(name, stb2.st_uid, stb2.st_gid);
+ chmod(name, stb2.st_mode & 07777);
+ }
+}
+
+/*
+ * 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 few 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;
+ 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
+ */
+ stb.st_mode = 0;
+ if (lstat(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.
+ * Easiest to read /proc/mdstat, and hunt through for
+ * an unused number
+ */
+ mdlist = mdstat_read(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);
+ if (dn==NULL || is_standard(dn)) {
+ /* this number only used by a 'standard' name,
+ * so it is safe to use
+ */
+ break;
+ }
+ }
+ }
+ /* 'num' is the number to use, >=0 for md, <0 for mdp */
+ if (must_remove) {
+ /* never remove a device name that ends /mdNN or /dNN,
+ * that would be confusing
+ */
+ if (is_standard(dev)) {
+ fprintf(stderr, Name ": --auto refusing to remove %s as it looks like a standard name.\n",
+ dev);
+ return -1;
+ }
+ unlink(dev);
+ }
+
+ if (mknod(dev, S_IFBLK|0600, MKDEV(major, minor))!= 0) {
+ fprintf(stderr, Name ": failed to create %s\n", dev);
+ return -1;
+ }
+ if (must_remove) {
+ chown(dev, stb.st_uid, stb.st_gid);
+ chmod(dev, stb.st_mode & 07777);
+ }
+ make_parts(dev,autof);
+ }
+ mdfd = open(dev, O_RDWR, 0);
projects / thirdparty / mdadm.git / blobdiff