[thirdparty/mdadm.git] / mdopen.c

/*
 * mdadm - manage Linux "md" devices aka RAID arrays.
 *
 * Copyright (C) 2001-2013 Neil Brown <neilb@suse.de>
 *
 *
 *    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@suse.de>
 */

#include "mdadm.h"
#include "md_p.h"
#include <ctype.h>

void make_parts(char *dev, int cnt)
{
	/* make 'cnt' partition devices for 'dev'
	 * If dev is a device name we use the
	 *  major/minor from dev and add 1..cnt
	 * If it is a symlink, we make similar symlinks.
	 * 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_num;
	int minor_num;
	int odig;
	int i;
	int nlen = strlen(dev) + 20;
	char *name;
	int dig = isdigit(dev[strlen(dev)-1]);
	char orig[1001];
	char sym[1024];
	int err;

	if (cnt == 0)
		cnt = 4;
	if (lstat(dev, &stb)!= 0)
		return;

	if (S_ISBLK(stb.st_mode)) {
		major_num = major(stb.st_rdev);
		minor_num = minor(stb.st_rdev);
		odig = -1;
	} else if (S_ISLNK(stb.st_mode)) {
		int len;

		len = readlink(dev, orig, sizeof(orig));
		if (len < 0 || len >= (int)sizeof(orig))
			return;
		orig[len] = 0;
		odig = isdigit(orig[len-1]);
		major_num = -1;
		minor_num = -1;
	} else
		return;
	name = xmalloc(nlen);
	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) || !S_ISBLK(stb.st_mode))
				continue;
			if (stb2.st_rdev == makedev(major_num, minor_num+i))
				continue;
			unlink(name);
		} else {
			stb2 = stb;
		}
		if (S_ISBLK(stb.st_mode)) {
			if (mknod(name, S_IFBLK | 0600,
				  makedev(major_num, minor_num+i)))
				perror("mknod");
			if (chown(name, stb2.st_uid, stb2.st_gid))
				perror("chown");
			if (chmod(name, stb2.st_mode & 07777))
				perror("chmod");
			err = 0;
		} else {
			snprintf(sym, sizeof(sym), "%s%s%d", orig, odig?"p":"", i);
			err = symlink(sym, name);
		}

		if (err == 0 && stat(name, &stb2) == 0)
			add_dev(name, &stb2, 0, NULL);
	}
	free(name);
}

int create_named_array(char *devnm)
{
	int fd;
	int n = -1;
	static const char new_array_file[] = {
		"/sys/module/md_mod/parameters/new_array"
	};

	fd = open(new_array_file, O_WRONLY);
	if (fd < 0 && errno == ENOENT) {
		if (system("modprobe md_mod") == 0)
			fd = open(new_array_file, O_WRONLY);
	}
	if (fd >= 0) {
		n = write(fd, devnm, strlen(devnm));
		close(fd);
	}
	if (fd < 0 || n != (int)strlen(devnm)) {
		pr_err("Fail create %s when using %s\n", devnm, new_array_file);
		return 0;
	}

	return 1;
}

/*
 * 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 if 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, char *name, int autof, int trustworthy,
		 char *chosen, int block_udev)
{
	int mdfd;
	struct stat stb;
	int num = -1;
	int use_mdp = -1;
	struct createinfo *ci = conf_get_create_info();
	int parts;
	char *cname;
	char devname[37];
	char devnm[32];
	char cbuf[400];

	if (!use_udev())
		block_udev = 0;

	if (chosen == NULL)
		chosen = cbuf;

	if (autof == 0)
		autof = ci->autof;

	parts = autof >> 3;
	autof &= 7;

	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)) {
				pr_err("%s is an invalid name for an md device.  Try /dev/md/%s\n",
					dev, dev+5);
				return -1;
			}
			if (strcmp(cname, "md") == 0)
				use_mdp = 0;
			else
				use_mdp = 1;
			/* recreate name: /dev/md/0 or /dev/md/d0 */
			sprintf(cname, "%s%d", use_mdp?"d":"", num);
		} else
			strcpy(cname, dev);

		/* 'cname' must not contain a slash, and may not be
		 * empty.
		 */
		if (strchr(cname, '/') != NULL) {
			pr_err("%s is an invalid name for an md device.\n", dev);
			return -1;
		}
		if (cname[0] == 0) {
			pr_err("%s is an invalid name for an md device (empty!).\n", dev);
			return -1;
		}
		if (num < 0) {
			/* If cname  is 'N' or 'dN', we get dev number
			 * from there.
			 */
			char *sp = cname;
			char *ep;
			if (cname[0] == 'd')
				sp++;
			if (isdigit(sp[0]))
				num = strtoul(sp, &ep, 10);
			else
				ep = sp;
			if (ep == sp || *ep || num < 0)
				num = -1;
			else if (cname[0] == 'd')
				use_mdp = 1;
			else
				use_mdp = 0;
		}
	}

	/* Now determine device number */
	/* named 'METADATA' cannot use 'mdp'. */
	if (name && name[0] == 0)
		name = NULL;
	if (name && trustworthy == METADATA && use_mdp == 1) {
		pr_err("%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
			use_mdp = 0;
	}
	if (num < 0 && trustworthy == LOCAL && name) {
		/* if name is numeric, possibly prefixed by
		 * 'md' or '/dev/md', use that for num
		 * if it is not already in use */
		char *ep;
		char *n2 = name;
		if (strncmp(n2, "/dev/", 5) == 0)
			n2 += 5;
		if (strncmp(n2, "md", 2) == 0)
			n2 += 2;
		if (*n2 == '/')
			n2++;
		num = strtoul(n2, &ep, 10);
		if (ep == n2 || *ep)
			num = -1;
		else {
			sprintf(devnm, "md%s%d", use_mdp ? "_d":"", num);
			if (mddev_busy(devnm))
				num = -1;
		}
	}

	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 '/'
		 */
		char *cp;
		struct map_ent *map = NULL;
		int conflict = 1;
		int unum = 0;
		int cnlen;
		strncpy(cname, name, 200);
		cname[200] = 0;
		for (cp = cname; *cp ; cp++)
			switch (*cp) {
			case '/':
				*cp = '-';
				break;
			case ' ':
			case '\t':
				*cp = '_';
				break;
			}

		if (trustworthy == LOCAL ||
		    (trustworthy == FOREIGN && strchr(cname, ':') != NULL)) {
			/* Only need suffix if there is a conflict */
			if (map_by_name(&map, cname) == NULL)
				conflict = 0;
		}
		cnlen = strlen(cname);
		while (conflict) {
			if (trustworthy == METADATA && !isdigit(cname[cnlen-1]))
				sprintf(cname+cnlen, "%d", unum);
			else
				/* add _%d to FOREIGN array that don't
				 * a 'host:' prefix
				 */
				sprintf(cname+cnlen, "_%d", unum);
			unum++;
			if (map_by_name(&map, cname) == NULL)
				conflict = 0;
		}
	}

	devnm[0] = 0;
	if (num < 0 && cname && ci->names) {
		sprintf(devnm, "md_%s", cname);
		if (block_udev)
			udev_block(devnm);
		if (!create_named_array(devnm)) {
			devnm[0] = 0;
			udev_unblock();
		}
	}
	if (num >= 0) {
		sprintf(devnm, "md%d", num);
		if (block_udev)
			udev_block(devnm);
		if (!create_named_array(devnm)) {
			devnm[0] = 0;
			udev_unblock();
		}
	}
	if (devnm[0] == 0) {
		if (num < 0) {
			/* need to choose a free number. */
			char *_devnm = find_free_devnm(use_mdp);
			if (_devnm == NULL) {
				pr_err("No avail md devices - aborting\n");
				return -1;
			}
			strcpy(devnm, _devnm);
		} else {
			sprintf(devnm, "%s%d", use_mdp?"md_d":"md", num);
			if (mddev_busy(devnm)) {
				pr_err("%s is already in use.\n",
				       dev);
				return -1;
			}
		}
		if (block_udev)
			udev_block(devnm);
	}

	sprintf(devname, "/dev/%s", devnm);

	if (dev && dev[0] == '/')
		strcpy(chosen, dev);
	else if (cname[0] == 0)
		strcpy(chosen, devname);

	/* We have a device number and name.
	 * If we cannot detect udev, we need to make
	 * devices and links ourselves.
	 */
	if (!use_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 != devnm2devid(devnm)) {
				pr_err("%s exists but looks wrong, please fix\n",
					devname);
				return -1;
			}
		} else {
			if (mknod(devname, S_IFBLK|0600,
				  devnm2devid(devnm)) != 0) {
				pr_err("failed to create %s\n",
					devname);
				return -1;
			}
			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 (use_mdp == 1)
			make_parts(devname, parts);

		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");
			}

			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];
				ssize_t link_len = readlink(chosen, buf, sizeof(buf)-1);
				if (link_len >= 0)
					buf[link_len] = '\0';

				if ((stb.st_mode & S_IFMT) != S_IFLNK ||
				    link_len < 0 ||
				    strcmp(buf, devname) != 0) {
					pr_err("%s exists - ignoring\n",
						chosen);
					strcpy(chosen, devname);
				}
			} else if (symlink(devname, chosen) != 0)
				pr_err("failed to create %s: %s\n",
					chosen, strerror(errno));
			if (use_mdp && strcmp(chosen, devname) != 0)
				make_parts(chosen, parts);
		}
	}
	mdfd = open_dev_excl(devnm);
	if (mdfd < 0)
		pr_err("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,
 * or -2 if it exists but is not an md device.
 */
int open_mddev(char *dev, int report_errors)
{
	int mdfd = open(dev, O_RDONLY);

	if (mdfd < 0) {
		if (report_errors)
			pr_err("error opening %s: %s\n",
				dev, strerror(errno));
		return -1;
	}

	if (md_array_valid(mdfd) == 0) {
		close(mdfd);
		if (report_errors)
			pr_err("%s does not appear to be an md device\n", dev);
		return -2;
	}

	return mdfd;
}

char *find_free_devnm(int use_partitions)
{
	static char devnm[32];
	int devnum;
	for (devnum = 127; devnum != 128;
	     devnum = devnum ? devnum-1 : (1<<9)-1) {

		if (use_partitions)
			sprintf(devnm, "md_d%d", devnum);
		else
			sprintf(devnm, "md%d", devnum);
		if (mddev_busy(devnm))
			continue;
		if (!conf_name_is_free(devnm))
			continue;
		if (!use_udev()) {
			/* make sure it is new to /dev too, at least as a
			 * non-standard */
			dev_t devid = devnm2devid(devnm);
			if (devid) {
				char *dn = map_dev(major(devid),
						   minor(devid), 0);
				if (dn && ! is_standard(dn, NULL))
					continue;
			}
		}
		break;
	}
	if (devnum == 128)
		return NULL;
	return devnm;
}
Commit	Line	Data
b5e64645 NB	1	/*
	2	* mdadm - manage Linux "md" devices aka RAID arrays.
	3	*
6f02172d	4	* Copyright (C) 2001-2013 Neil Brown <neilb@suse.de>
b5e64645 NB	5	*
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*
	21	* Author: Neil Brown
e736b623	22	* Email: <neilb@suse.de>
b5e64645 NB	23	*/
	24
	25	#include "mdadm.h"
	26	#include "md_p.h"
	27	#include <ctype.h>
	28
c4fe2d4f	29	void make_parts(char *dev, int cnt)
b5e64645 NB	30	{
b5e64645 NB	31	/* make 'cnt' partition devices for 'dev'
c4fe2d4f N	32	* If dev is a device name we use the
	33	* major/minor from dev and add 1..cnt
	34	* If it is a symlink, we make similar symlinks.
8d80900b	35	* If dev ends with a digit, we add "p%d" else "%d"
b5e64645 NB	36	* If the name exists, we use it's owner/mode,
	37	* else that of dev
	38	*/
	39	struct stat stb;
96ae5973 JS	40	int major_num;
	41	int minor_num;
	42	int odig;
b5e64645	43	int i;
8f23b0b3	44	int nlen = strlen(dev) + 20;
0eb26465	45	char *name;
b5e64645	46	int dig = isdigit(dev[strlen(dev)-1]);
c1b78589	47	char orig[1001];
c4fe2d4f	48	char sym[1024];
614825ea	49	int err;
b5e64645	50
ca3b6696 N	51	if (cnt == 0)
ca3b6696 N	52	cnt = 4;
c4fe2d4f	53	if (lstat(dev, &stb)!= 0)
b5e64645	54	return;
0eb26465	55
96ae5973 JS	56	if (S_ISBLK(stb.st_mode)) {
	57	major_num = major(stb.st_rdev);
	58	minor_num = minor(stb.st_rdev);
	59	odig = -1;
	60	} else if (S_ISLNK(stb.st_mode)) {
c1b78589 JS	61	int len;
	62
	63	len = readlink(dev, orig, sizeof(orig));
	64	if (len < 0 \|\| len >= (int)sizeof(orig))
c4fe2d4f N	65	return;
	66	orig[len] = 0;
	67	odig = isdigit(orig[len-1]);
96ae5973 JS	68	major_num = -1;
96ae5973 JS	69	minor_num = -1;
c4fe2d4f	70	} else
96ae5973	71	return;
503975b9	72	name = xmalloc(nlen);
ca3b6696	73	for (i = 1; i <= cnt ; i++) {
b5e64645	74	struct stat stb2;
8f23b0b3	75	snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i);
ca3b6696	76	if (stat(name, &stb2) == 0) {
96ae5973	77	if (!S_ISBLK(stb2.st_mode) \|\| !S_ISBLK(stb.st_mode))
b5e64645	78	continue;
b440882e	79	if (stb2.st_rdev == makedev(major_num, minor_num+i))
b5e64645 NB	80	continue;
	81	unlink(name);
	82	} else {
	83	stb2 = stb;
	84	}
c4fe2d4f N	85	if (S_ISBLK(stb.st_mode)) {
	86	if (mknod(name, S_IFBLK \| 0600,
	87	makedev(major_num, minor_num+i)))
	88	perror("mknod");
	89	if (chown(name, stb2.st_uid, stb2.st_gid))
	90	perror("chown");
	91	if (chmod(name, stb2.st_mode & 07777))
	92	perror("chmod");
614825ea	93	err = 0;
c4fe2d4f	94	} else {
e10a79c3	95	snprintf(sym, sizeof(sym), "%s%s%d", orig, odig?"p":"", i);
614825ea	96	err = symlink(sym, name);
c4fe2d4f	97	}
614825ea DW	98
	99	if (err == 0 && stat(name, &stb2) == 0)
	100	add_dev(name, &stb2, 0, NULL);
b5e64645	101	}
0eb26465	102	free(name);
b5e64645 NB	103	}
b5e64645 NB	104
7105228e ZL	105	int create_named_array(char *devnm)
	106	{
	107	int fd;
	108	int n = -1;
	109	static const char new_array_file[] = {
	110	"/sys/module/md_mod/parameters/new_array"
	111	};
	112
	113	fd = open(new_array_file, O_WRONLY);
	114	if (fd < 0 && errno == ENOENT) {
	115	if (system("modprobe md_mod") == 0)
	116	fd = open(new_array_file, O_WRONLY);
	117	}
	118	if (fd >= 0) {
	119	n = write(fd, devnm, strlen(devnm));
	120	close(fd);
	121	}
	122	if (fd < 0 \|\| n != (int)strlen(devnm)) {
	123	pr_err("Fail create %s when using %s\n", devnm, new_array_file);
	124	return 0;
	125	}
	126
	127	return 1;
	128	}
	129
b5e64645	130	/*
69207ff6 N	131	* We need a new md device to assemble/build/create an array.
	132	* 'dev' is a name given us by the user (command line or mdadm.conf)
	133	* It might start with /dev or /dev/md any might end with a digit
	134	* string.
	135	* If it starts with just /dev, it must be /dev/mdX or /dev/md_dX
	136	* If it ends with a digit string, then it must be as above, or
	137	* 'trustworthy' must be 'METADATA' and the 'dev' must be
	138	* /dev/md/'name'NN or 'name'NN
	139	* If it doesn't end with a digit string, it must be /dev/md/'name'
	140	* or 'name' or must be NULL.
	141	* If the digit string is present, it gives the minor number to use
	142	* If not, we choose a high, unused minor number.
	143	* If the 'dev' is a standard name, it devices whether 'md' or 'mdp'.
	144	* else if the name is 'd[0-9]+' then we use mdp
	145	* else if trustworthy is 'METADATA' we use md
	146	* else the choice depends on 'autof'.
	147	* If name is NULL it is assumed to match whatever dev provides.
	148	* If both name and dev are NULL, we choose a name 'mdXX' or 'mdpXX'
	149	*
	150	* If 'name' is given, and 'trustworthy' is 'foreign' and name is not
	151	* supported by 'dev', we add a "_%d" suffix based on the minor number
	152	* use that.
	153	*
ca3b6696	154	* If udev is configured, we create a temporary device, open it, and
69207ff6	155	* unlink it.
eca944fa	156	* If not, we create the /dev/mdXX device, and if name is usable,
69207ff6 N	157	* /dev/md/name
	158	* In any case we return /dev/md/name or (if that isn't available)
	159	* /dev/mdXX in 'chosen'.
	160	*
	161	* When we create devices, we use uid/gid/umask from config file.
b5e64645	162	*/
69207ff6 N	163
69207ff6 N	164	int create_mddev(char dev, char name, int autof, int trustworthy,
cd6cbb08	165	char *chosen, int block_udev)
b5e64645 NB	166	{
	167	int mdfd;
	168	struct stat stb;
69207ff6 N	169	int num = -1;
69207ff6 N	170	int use_mdp = -1;
8aec876d	171	struct createinfo *ci = conf_get_create_info();
f1ae21c4	172	int parts;
69207ff6	173	char *cname;
bd1fd72e	174	char devname[37];
4dd2df09	175	char devnm[32];
69207ff6	176	char cbuf[400];
cd6cbb08 N	177
	178	if (!use_udev())
	179	block_udev = 0;
	180
69207ff6 N	181	if (chosen == NULL)
	182	chosen = cbuf;
	183
5bbb4842 NB	184	if (autof == 0)
	185	autof = ci->autof;
	186
f1ae21c4 NB	187	parts = autof >> 3;
	188	autof &= 7;
	189
69207ff6 N	190	strcpy(chosen, "/dev/md/");
	191	cname = chosen + strlen(chosen);
	192
69207ff6	193	if (dev) {
69207ff6 N	194	if (strncmp(dev, "/dev/md/", 8) == 0) {
	195	strcpy(cname, dev+8);
	196	} else if (strncmp(dev, "/dev/", 5) == 0) {
	197	char *e = dev + strlen(dev);
	198	while (e > dev && isdigit(e[-1]))
	199	e--;
	200	if (e[0])
	201	num = strtoul(e, NULL, 10);
	202	strcpy(cname, dev+5);
	203	cname[e-(dev+5)] = 0;
	204	/* name must be mdXX or md_dXX in this context */
	205	if (num < 0 \|\|
	206	(strcmp(cname, "md") != 0 && strcmp(cname, "md_d") != 0)) {
7a862a02	207	pr_err("%s is an invalid name for an md device. Try /dev/md/%s\n",
69207ff6	208	dev, dev+5);
f1ae21c4 NB	209	return -1;
f1ae21c4 NB	210	}
69207ff6 N	211	if (strcmp(cname, "md") == 0)
	212	use_mdp = 0;
	213	else
	214	use_mdp = 1;
11fb4c05 N	215	/* recreate name: /dev/md/0 or /dev/md/d0 */
11fb4c05 N	216	sprintf(cname, "%s%d", use_mdp?"d":"", num);
69207ff6 N	217	} else
	218	strcpy(cname, dev);
	219
11fb4c05 N	220	/* 'cname' must not contain a slash, and may not be
11fb4c05 N	221	* empty.
69207ff6	222	*/
11fb4c05	223	if (strchr(cname, '/') != NULL) {
7a862a02	224	pr_err("%s is an invalid name for an md device.\n", dev);
69207ff6	225	return -1;
f1ae21c4	226	}
11fb4c05	227	if (cname[0] == 0) {
8e5b52cd	228	pr_err("%s is an invalid name for an md device (empty!).\n", dev);
69207ff6	229	return -1;
b5e64645	230	}
11fb4c05 N	231	if (num < 0) {
	232	/* If cname is 'N' or 'dN', we get dev number
	233	* from there.
	234	*/
	235	char *sp = cname;
	236	char *ep;
	237	if (cname[0] == 'd')
	238	sp++;
4cda8682 JM	239	if (isdigit(sp[0]))
	240	num = strtoul(sp, &ep, 10);
	241	else
	242	ep = sp;
11fb4c05 N	243	if (ep == sp \|\| *ep \|\| num < 0)
	244	num = -1;
	245	else if (cname[0] == 'd')
	246	use_mdp = 1;
	247	else
	248	use_mdp = 0;
	249	}
69207ff6	250	}
f1ae21c4	251
69207ff6 N	252	/* Now determine device number */
	253	/* named 'METADATA' cannot use 'mdp'. */
	254	if (name && name[0] == 0)
	255	name = NULL;
	256	if (name && trustworthy == METADATA && use_mdp == 1) {
7a862a02	257	pr_err("%s is not allowed for a %s container. Consider /dev/md%d.\n", dev, name, num);
69207ff6 N	258	return -1;
	259	}
	260	if (name && trustworthy == METADATA)
	261	use_mdp = 0;
	262	if (use_mdp == -1) {
	263	if (autof == 4 \|\| autof == 6)
	264	use_mdp = 1;
f1ae21c4	265	else
69207ff6 N	266	use_mdp = 0;
	267	}
	268	if (num < 0 && trustworthy == LOCAL && name) {
ca3b6696	269	/* if name is numeric, possibly prefixed by
d7ba0c55	270	* 'md' or '/dev/md', use that for num
bde2c6e2	271	* if it is not already in use */
69207ff6	272	char *ep;
d7ba0c55 N	273	char *n2 = name;
	274	if (strncmp(n2, "/dev/", 5) == 0)
	275	n2 += 5;
	276	if (strncmp(n2, "md", 2) == 0)
	277	n2 += 2;
	278	if (*n2 == '/')
	279	n2++;
	280	num = strtoul(n2, &ep, 10);
	281	if (ep == n2 \|\| *ep)
69207ff6	282	num = -1;
4dd2df09 N	283	else {
	284	sprintf(devnm, "md%s%d", use_mdp ? "_d":"", num);
	285	if (mddev_busy(devnm))
	286	num = -1;
	287	}
69207ff6 N	288	}
69207ff6 N	289
69207ff6 N	290	if (cname[0] == 0 && name) {
	291	/* Need to find a name if we can
	292	* We don't completely trust 'name'. Truncate to
	293	* reasonable length and remove '/'
8d80900b	294	*/
69207ff6	295	char *cp;
f2e55ecc N	296	struct map_ent *map = NULL;
	297	int conflict = 1;
	298	int unum = 0;
	299	int cnlen;
69207ff6 N	300	strncpy(cname, name, 200);
69207ff6 N	301	cname[200] = 0;
7103b9b8 N	302	for (cp = cname; *cp ; cp++)
	303	switch (*cp) {
	304	case '/':
	305	*cp = '-';
	306	break;
	307	case ' ':
	308	case '\t':
	309	*cp = '_';
	310	break;
	311	}
	312
f2e55ecc N	313	if (trustworthy == LOCAL \|\|
	314	(trustworthy == FOREIGN && strchr(cname, ':') != NULL)) {
	315	/* Only need suffix if there is a conflict */
	316	if (map_by_name(&map, cname) == NULL)
	317	conflict = 0;
	318	}
	319	cnlen = strlen(cname);
	320	while (conflict) {
add394f3	321	if (trustworthy == METADATA && !isdigit(cname[cnlen-1]))
f2e55ecc N	322	sprintf(cname+cnlen, "%d", unum);
f2e55ecc N	323	else
ca3b6696	324	/* add _%d to FOREIGN array that don't
f2e55ecc N	325	* a 'host:' prefix
	326	*/
	327	sprintf(cname+cnlen, "_%d", unum);
	328	unum++;
	329	if (map_by_name(&map, cname) == NULL)
	330	conflict = 0;
	331	}
69207ff6	332	}
9a40c327	333
eca944fa N	334	devnm[0] = 0;
eca944fa N	335	if (num < 0 && cname && ci->names) {
eca944fa	336	sprintf(devnm, "md_%s", cname);
cd6cbb08 N	337	if (block_udev)
cd6cbb08 N	338	udev_block(devnm);
7105228e	339	if (!create_named_array(devnm)) {
eca944fa	340	devnm[0] = 0;
cd6cbb08 N	341	udev_unblock();
cd6cbb08 N	342	}
eca944fa	343	}
039df362	344	if (num >= 0) {
039df362	345	sprintf(devnm, "md%d", num);
cd6cbb08 N	346	if (block_udev)
cd6cbb08 N	347	udev_block(devnm);
7105228e	348	if (!create_named_array(devnm)) {
039df362	349	devnm[0] = 0;
cd6cbb08	350	udev_unblock();
eca944fa	351	}
cd6cbb08 N	352	}
	353	if (devnm[0] == 0) {
	354	if (num < 0) {
	355	/* need to choose a free number. */
	356	char *_devnm = find_free_devnm(use_mdp);
	357	if (_devnm == NULL) {
	358	pr_err("No avail md devices - aborting\n");
	359	return -1;
	360	}
	361	strcpy(devnm, _devnm);
	362	} else {
	363	sprintf(devnm, "%s%d", use_mdp?"md_d":"md", num);
	364	if (mddev_busy(devnm)) {
	365	pr_err("%s is already in use.\n",
	366	dev);
	367	return -1;
	368	}
eca944fa	369	}
cd6cbb08 N	370	if (block_udev)
cd6cbb08 N	371	udev_block(devnm);
eca944fa N	372	}
	373
	374	sprintf(devname, "/dev/%s", devnm);
	375
5ac6db12	376	if (dev && dev[0] == '/')
9a40c327 N	377	strcpy(chosen, dev);
9a40c327 N	378	else if (cname[0] == 0)
69207ff6	379	strcpy(chosen, devname);
8d80900b	380
69207ff6	381	/* We have a device number and name.
11fb4c05 N	382	* If we cannot detect udev, we need to make
11fb4c05 N	383	* devices and links ourselves.
69207ff6	384	*/
06d2ffc3	385	if (!use_udev()) {
69207ff6 N	386	/* Make sure 'devname' exists and 'chosen' is a symlink to it */
	387	if (lstat(devname, &stb) == 0) {
	388	/* Must be the correct device, else error */
	389	if ((stb.st_mode&S_IFMT) != S_IFBLK \|\|
13db17bd	390	stb.st_rdev != devnm2devid(devnm)) {
e7b84f9d	391	pr_err("%s exists but looks wrong, please fix\n",
69207ff6 N	392	devname);
69207ff6 N	393	return -1;
0a6e1c67	394	}
69207ff6 N	395	} else {
69207ff6 N	396	if (mknod(devname, S_IFBLK\|0600,
4dd2df09	397	devnm2devid(devnm)) != 0) {
e7b84f9d	398	pr_err("failed to create %s\n",
69207ff6	399	devname);
b5e64645 NB	400	return -1;
b5e64645 NB	401	}
69207ff6 N	402	if (chown(devname, ci->uid, ci->gid))
	403	perror("chown");
	404	if (chmod(devname, ci->mode))
	405	perror("chmod");
	406	stat(devname, &stb);
	407	add_dev(devname, &stb, 0, NULL);
	408	}
c4fe2d4f N	409	if (use_mdp == 1)
c4fe2d4f N	410	make_parts(devname, parts);
69207ff6	411
ca3b6696 N	412	if (strcmp(chosen, devname) != 0) {
ca3b6696 N	413	if (mkdir("/dev/md",0700) == 0) {
69207ff6 N	414	if (chown("/dev/md", ci->uid, ci->gid))
	415	perror("chown /dev/md");
	416	if (chmod("/dev/md", ci->mode\| ((ci->mode>>2) & 0111)))
	417	perror("chmod /dev/md");
8d80900b	418	}
69207ff6 N	419
	420	if (dev && strcmp(chosen, dev) == 0)
	421	/* We know we are allowed to use this name */
	422	unlink(chosen);
	423
	424	if (lstat(chosen, &stb) == 0) {
	425	char buf[300];
fca13185 TJ	426	ssize_t link_len = readlink(chosen, buf, sizeof(buf)-1);
	427	if (link_len >= 0)
	428	buf[link_len] = '\0';
	429
69207ff6	430	if ((stb.st_mode & S_IFMT) != S_IFLNK \|\|
fca13185	431	link_len < 0 \|\|
69207ff6	432	strcmp(buf, devname) != 0) {
e7b84f9d	433	pr_err("%s exists - ignoring\n",
69207ff6 N	434	chosen);
	435	strcpy(chosen, devname);
	436	}
614825ea	437	} else if (symlink(devname, chosen) != 0)
e7b84f9d	438	pr_err("failed to create %s: %s\n",
614825ea	439	chosen, strerror(errno));
c4fe2d4f N	440	if (use_mdp && strcmp(chosen, devname) != 0)
c4fe2d4f N	441	make_parts(chosen, parts);
b5e64645	442	}
b5e64645	443	}
4dd2df09	444	mdfd = open_dev_excl(devnm);
69207ff6	445	if (mdfd < 0)
e7b84f9d	446	pr_err("unexpected failure opening %s\n",
69207ff6	447	devname);
6be1d39d N	448	return mdfd;
	449	}
	450
	451	/* Open this and check that it is an md device.
	452	* On success, return filedescriptor.
	453	* On failure, return -1 if it doesn't exist,
	454	* or -2 if it exists but is not an md device.
	455	*/
	456	int open_mddev(char *dev, int report_errors)
	457	{
f71d2b8f	458	int mdfd = open(dev, O_RDONLY);
40b054e1	459
6be1d39d N	460	if (mdfd < 0) {
6be1d39d N	461	if (report_errors)
e7b84f9d	462	pr_err("error opening %s: %s\n",
6be1d39d N	463	dev, strerror(errno));
	464	return -1;
	465	}
40b054e1	466
9db2ab4e	467	if (md_array_valid(mdfd) == 0) {
b5e64645	468	close(mdfd);
6be1d39d	469	if (report_errors)
7a862a02	470	pr_err("%s does not appear to be an md device\n", dev);
6be1d39d	471	return -2;
b5e64645	472	}
40b054e1	473
b5e64645 NB	474	return mdfd;
b5e64645 NB	475	}
289c74f8 N	476
	477	char *find_free_devnm(int use_partitions)
	478	{
	479	static char devnm[32];
	480	int devnum;
	481	for (devnum = 127; devnum != 128;
2e466cce	482	devnum = devnum ? devnum-1 : (1<<9)-1) {
289c74f8 N	483
	484	if (use_partitions)
	485	sprintf(devnm, "md_d%d", devnum);
	486	else
	487	sprintf(devnm, "md%d", devnum);
	488	if (mddev_busy(devnm))
	489	continue;
	490	if (!conf_name_is_free(devnm))
	491	continue;
	492	if (!use_udev()) {
	493	/* make sure it is new to /dev too, at least as a
	494	* non-standard */
13db17bd	495	dev_t devid = devnm2devid(devnm);
289c74f8 N	496	if (devid) {
	497	char *dn = map_dev(major(devid),
	498	minor(devid), 0);
	499	if (dn && ! is_standard(dn, NULL))
	500	continue;
	501	}
	502	}
	503	break;
	504	}
	505	if (devnum == 128)
	506	return NULL;
	507	return devnm;
	508	}