/*
- * 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/mode comes from config file.
+ * We need a new md device to assemble/build/create an array.
+ * 'dev' is a name given us by the user (command line or mdadm.conf)
+ * It might start with /dev or /dev/md any might end with a digit
+ * string.
+ * If it starts with just /dev, it must be /dev/mdX or /dev/md_dX
+ * If it ends with a digit string, then it must be as above, or
+ * 'trustworthy' must be 'METADATA' and the 'dev' must be
+ * /dev/md/'name'NN or 'name'NN
+ * If it doesn't end with a digit string, it must be /dev/md/'name'
+ * or 'name' or must be NULL.
+ * If the digit string is present, it gives the minor number to use
+ * If not, we choose a high, unused minor number.
+ * If the 'dev' is a standard name, it devices whether 'md' or 'mdp'.
+ * else if the name is 'd[0-9]+' then we use mdp
+ * else if trustworthy is 'METADATA' we use md
+ * else the choice depends on 'autof'.
+ * If name is NULL it is assumed to match whatever dev provides.
+ * If both name and dev are NULL, we choose a name 'mdXX' or 'mdpXX'
+ *
+ * If 'name' is given, and 'trustworthy' is 'foreign' and name is not
+ * supported by 'dev', we add a "_%d" suffix based on the minor number
+ * use that.
+ *
+ * If udev is configured, we create a temporary device, open it, and
+ * unlink it.
+ * If not, we create the /dev/mdXX device, and is name is usable,
+ * /dev/md/name
+ * In any case we return /dev/md/name or (if that isn't available)
+ * /dev/mdXX in 'chosen'.
+ *
+ * When we create devices, we use uid/gid/umask from config file.
*/
-int create_mddev(char *dev, int autof)
+
+int create_mddev(char *dev, char *name, int autof, int trustworthy,
+ char *chosen)
{
int mdfd;
struct stat stb;
- int major_num = MD_MAJOR;
- int minor_num = 0;
- int must_remove = 0;
- int num;
+ int num = -1;
+ int use_mdp = -1;
struct createinfo *ci = conf_get_create_info();
int parts;
+ char *cname;
+ char devname[20];
+ char cbuf[400];
+ if (chosen == NULL)
+ chosen = cbuf;
+
if (autof == 0)
autof = ci->autof;
parts = autof >> 3;
autof &= 7;
- if (autof && autof != 1) {
- /* autof is set, so we need to check that the name is ok,
- * and possibly create one if not
- */
- int std;
- 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 */
- num = -1;
- std = is_standard(dev, &num);
- if (std>0) major_num = get_mdp_major();
- switch(autof) {
- case 2: /* only create is_standard names */
- if (!std && !stb.st_mode) {
- fprintf(stderr, Name
- ": %s does not exist and is not a 'standard' name "
- "so it cannot be created\n", dev);
- return -1;
- }
- break;
- case 3: /* create md, reject std>0 */
- if (std > 0) {
- fprintf(stderr, Name ": that --auto option "
- "not compatable with device named %s\n", dev);
- return -1;
- }
- break;
- case 4: /* create mdp, reject std<0 */
- if (std < 0) {
- fprintf(stderr, Name ": that --auto option "
- "not compatable with device named %s\n", dev);
+ strcpy(chosen, "/dev/md/");
+ cname = chosen + strlen(chosen);
+
+
+ if (dev) {
+
+ if (strncmp(dev, "/dev/md/", 8) == 0) {
+ strcpy(cname, dev+8);
+ } else if (strncmp(dev, "/dev/", 5) == 0) {
+ char *e = dev + strlen(dev);
+ while (e > dev && isdigit(e[-1]))
+ e--;
+ if (e[0])
+ num = strtoul(e, NULL, 10);
+ strcpy(cname, dev+5);
+ cname[e-(dev+5)] = 0;
+ /* name *must* be mdXX or md_dXX in this context */
+ if (num < 0 ||
+ (strcmp(cname, "md") != 0 && strcmp(cname, "md_d") != 0)) {
+ fprintf(stderr, Name ": %s is an invalid name "
+ "for an md device. Try /dev/md/%s\n",
+ dev, dev+5);
return -1;
}
- major_num = get_mdp_major();
- break;
- case 5: /* default to md if not standard */
- break;
- case 6: /* default to mdp if not standard */
- if (std == 0) major_num = get_mdp_major();
- break;
+ if (strcmp(cname, "md") == 0)
+ use_mdp = 0;
+ else
+ use_mdp = 1;
+ } else
+ strcpy(cname, dev);
+
+ /* 'cname' must not contain a slash, may not start or end
+ * with a digit, and may only be empty if num is present.
+ */
+ if (strchr(cname, '/') != NULL ||
+ isdigit(cname[0]) ||
+ (cname[0] && isdigit(cname[strlen(cname)]))
+ ) {
+ fprintf(stderr, Name ": %s is an invalid name "
+ "for an md device.\n", dev);
+ return -1;
}
- /* major is final. num is -1 if not standard */
- if (stb.st_mode && major(stb.st_rdev) != major_num)
- must_remove = 1;
- if (stb.st_mode && !must_remove) {
- /* looks ok, see if it is available */
- mdfd = open(dev, O_RDWR);
- 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 (major_num != MD_MAJOR && parts > 0)
- make_parts(dev, parts, ci->symlinks);
- return mdfd;
+ if (cname[0] == 0 && num < 0) {
+ fprintf(stderr, Name ": %s is an invalid name "
+ "for an md device (empty!).", dev);
+ return -1;
}
- /* 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
- */
- if (num < 0) {
- /* need to pick an unused number */
- int num = find_free_devnum(major_num != MD_MAJOR);
+ }
- if (major_num == MD_MAJOR)
- minor_num = num;
- else
- minor_num = (-1-num) << MdpMinorShift;
- } else if (major_num == MD_MAJOR)
- minor_num = num;
+ /* Now determine device number */
+ /* named 'METADATA' cannot use 'mdp'. */
+ if (name && name[0] == 0)
+ name = NULL;
+ if (name && trustworthy == METADATA && use_mdp == 1) {
+ fprintf(stderr, Name ": %s is not allowed for a %s container. "
+ "Consider /dev/md%d.\n", dev, name, num);
+ return -1;
+ }
+ if (name && trustworthy == METADATA)
+ use_mdp = 0;
+ if (use_mdp == -1) {
+ if (autof == 4 || autof == 6)
+ use_mdp = 1;
else
- minor_num = num << MdpMinorShift;
- /* major and minor have been chosen */
+ use_mdp = 0;
+ }
+ if (num < 0 && trustworthy == LOCAL && name) {
+ /* if name is numeric, us that for num */
+ char *ep;
+ num = strtoul(name, &ep, 10);
+ if (ep == name || *ep)
+ num = -1;
+ }
+
+ if (num < 0) {
+ /* need to choose a free number. */
+ num = find_free_devnum(use_mdp);
+ if (num == NoMdDev) {
+ fprintf(stderr, Name ": No avail md devices - aborting\n");
+ return -1;
+ }
+ } else {
+ num = use_mdp ? (-1-num) : num;
+ if (mddev_busy(num)) {
+ fprintf(stderr, Name ": %s is already in use.\n",
+ dev);
+ return -1;
+ }
+ }
- /* If it was a 'standard' name and it is in-use, then
- * the device could already be correct
+ if (num < 0)
+ sprintf(devname, "/dev/md_d%d", -1-num);
+ else
+ sprintf(devname, "/dev/md%d", num);
+
+ if (cname[0] == 0 && name) {
+ /* Need to find a name if we can
+ * We don't completely trust 'name'. Truncate to
+ * reasonable length and remove '/'
*/
- if (stb.st_mode && major(stb.st_rdev) == major_num &&
- minor(stb.st_rdev) == minor_num)
- ;
- else {
- if (major(makedev(major_num,minor_num)) != major_num ||
- minor(makedev(major_num,minor_num)) != minor_num) {
- fprintf(stderr, Name ": Need newer C library to use more than 4 partitionable md devices, sorry\n");
+ char *cp;
+ strncpy(cname, name, 200);
+ cname[200] = 0;
+ while ((cp = strchr(cname, '/')) != NULL)
+ *cp = '-';
+ if (trustworthy == METADATA)
+ /* always add device number to metadata */
+ sprintf(cname+strlen(cname), "%d", num);
+ else if (trustworthy == FOREIGN &&
+ strchr(cname, ':') == NULL)
+ /* add _%d to FOREIGN array that don't have
+ * a 'host:' prefix
+ */
+ sprintf(cname+strlen(cname), "_%d", num<0?(-1-num):num);
+ }
+ if (cname[0] == 0)
+ strcpy(chosen, devname);
+
+ /* We have a device number and name.
+ * If we can detect udev, just open the device and we
+ * are done.
+ */
+ if (stat("/dev/.udev", &stb) != 0 ||
+ check_env("MDADM_NO_UDEV")) {
+ /* Make sure 'devname' exists and 'chosen' is a symlink to it */
+ if (lstat(devname, &stb) == 0) {
+ /* Must be the correct device, else error */
+ if ((stb.st_mode&S_IFMT) != S_IFBLK ||
+ stb.st_rdev != makedev(dev2major(num),dev2minor(num))) {
+ fprintf(stderr, Name ": %s exists but looks wrong, please fix\n",
+ devname);
return -1;
}
- if (must_remove)
- unlink(dev);
-
- if (strncmp(dev, "/dev/md/", 8) == 0) {
- if (mkdir("/dev/md",0700)==0) {
- if (chown("/dev/md", ci->uid, ci->gid))
- perror("chown /dev/md");
- if (chmod("/dev/md", ci->mode| ((ci->mode>>2) & 0111)))
- perror("chmod /dev/md");
- }
- }
- if (mknod(dev, S_IFBLK|0600, makedev(major_num, minor_num))!= 0) {
- fprintf(stderr, Name ": failed to create %s\n", dev);
+ } else {
+ if (mknod(devname, S_IFBLK|0600,
+ makedev(dev2major(num),dev2minor(num))) != 0) {
+ fprintf(stderr, Name ": failed to create %s\n",
+ devname);
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");
- } else {
- if (chown(dev, ci->uid, ci->gid))
- perror("chown");
- if (chmod(dev, ci->mode))
- perror("chmod");
+ if (chown(devname, ci->uid, ci->gid))
+ perror("chown");
+ if (chmod(devname, ci->mode))
+ perror("chmod");
+ stat(devname, &stb);
+ add_dev(devname, &stb, 0, NULL);
+ }
+ if (strcmp(chosen, devname) != 0) {
+
+ if (mkdir("/dev/md",0700)==0) {
+ if (chown("/dev/md", ci->uid, ci->gid))
+ perror("chown /dev/md");
+ if (chmod("/dev/md", ci->mode| ((ci->mode>>2) & 0111)))
+ perror("chmod /dev/md");
}
- stat(dev, &stb);
- add_dev(dev, &stb, 0, NULL);
- if (ci->symlinks && strncmp(dev, "/dev/md/", 8) == 0)
- make_dev_symlink(dev);
- if (major_num != MD_MAJOR)
- make_parts(dev,parts, ci->symlinks);
+
+ if (dev && strcmp(chosen, dev) == 0)
+ /* We know we are allowed to use this name */
+ unlink(chosen);
+
+ if (lstat(chosen, &stb) == 0) {
+ char buf[300];
+ if ((stb.st_mode & S_IFMT) != S_IFLNK ||
+ readlink(chosen, buf, 300) <0 ||
+ strcmp(buf, devname) != 0) {
+ fprintf(stderr, Name ": %s exists - ignoring\n",
+ chosen);
+ strcpy(chosen, devname);
+ }
+ } else
+ symlink(devname, chosen);
}
}
- mdfd = open_mddev(dev, 1);
+ mdfd = open_dev_excl(num);
+ if (mdfd < 0)
+ fprintf(stderr, Name ": unexpected failure opening %s\n",
+ devname);
return mdfd;
}
+
/* Open this and check that it is an md device.
* On success, return filedescriptor.
* On failure, return -1 if it doesn't exist,
projects / thirdparty / mdadm.git / commitdiff
