[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[1024];
	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 = readlink(dev, orig, sizeof(orig));
		if (len < 0 || len > 1000)
			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);
}

/*
 * 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) {
		int fd;
		int n = -1;
		sprintf(devnm, "md_%s", cname);
		if (block_udev)
			udev_block(devnm);
		fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
		if (fd < 0 && errno == ENOENT) {
			system("modprobe md_mod");
			fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
		}
		if (fd >= 0) {
			n = write(fd, devnm, strlen(devnm));
			close(fd);
		}
		if (n < 0) {
			devnm[0] = 0;
			udev_unblock();
		}
	}
	if (num >= 0) {
		int fd;
		int n = -1;
		sprintf(devnm, "md%d", num);
		if (block_udev)
			udev_block(devnm);
		fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
		if (fd >= 0) {
			n = write(fd, devnm, strlen(devnm));
			close(fd);
		}
		if (n < 0) {
			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]);
c4fe2d4f N	47	char orig[1024];
c4fe2d4f N	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)) {
c4fe2d4f N	61	int len = readlink(dev, orig, sizeof(orig));
	62	if (len < 0 \|\| len > 1000)
	63	return;
	64	orig[len] = 0;
	65	odig = isdigit(orig[len-1]);
96ae5973 JS	66	major_num = -1;
96ae5973 JS	67	minor_num = -1;
c4fe2d4f	68	} else
96ae5973	69	return;
503975b9	70	name = xmalloc(nlen);
ca3b6696	71	for (i = 1; i <= cnt ; i++) {
b5e64645	72	struct stat stb2;
8f23b0b3	73	snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i);
ca3b6696	74	if (stat(name, &stb2) == 0) {
96ae5973	75	if (!S_ISBLK(stb2.st_mode) \|\| !S_ISBLK(stb.st_mode))
b5e64645	76	continue;
b440882e	77	if (stb2.st_rdev == makedev(major_num, minor_num+i))
b5e64645 NB	78	continue;
	79	unlink(name);
	80	} else {
	81	stb2 = stb;
	82	}
c4fe2d4f N	83	if (S_ISBLK(stb.st_mode)) {
	84	if (mknod(name, S_IFBLK \| 0600,
	85	makedev(major_num, minor_num+i)))
	86	perror("mknod");
	87	if (chown(name, stb2.st_uid, stb2.st_gid))
	88	perror("chown");
	89	if (chmod(name, stb2.st_mode & 07777))
	90	perror("chmod");
614825ea	91	err = 0;
c4fe2d4f	92	} else {
e10a79c3	93	snprintf(sym, sizeof(sym), "%s%s%d", orig, odig?"p":"", i);
614825ea	94	err = symlink(sym, name);
c4fe2d4f	95	}
614825ea DW	96
	97	if (err == 0 && stat(name, &stb2) == 0)
	98	add_dev(name, &stb2, 0, NULL);
b5e64645	99	}
0eb26465	100	free(name);
b5e64645 NB	101	}
	102
	103	/*
69207ff6 N	104	* We need a new md device to assemble/build/create an array.
	105	* 'dev' is a name given us by the user (command line or mdadm.conf)
	106	* It might start with /dev or /dev/md any might end with a digit
	107	* string.
	108	* If it starts with just /dev, it must be /dev/mdX or /dev/md_dX
	109	* If it ends with a digit string, then it must be as above, or
	110	* 'trustworthy' must be 'METADATA' and the 'dev' must be
	111	* /dev/md/'name'NN or 'name'NN
	112	* If it doesn't end with a digit string, it must be /dev/md/'name'
	113	* or 'name' or must be NULL.
	114	* If the digit string is present, it gives the minor number to use
	115	* If not, we choose a high, unused minor number.
	116	* If the 'dev' is a standard name, it devices whether 'md' or 'mdp'.
	117	* else if the name is 'd[0-9]+' then we use mdp
	118	* else if trustworthy is 'METADATA' we use md
	119	* else the choice depends on 'autof'.
	120	* If name is NULL it is assumed to match whatever dev provides.
	121	* If both name and dev are NULL, we choose a name 'mdXX' or 'mdpXX'
	122	*
	123	* If 'name' is given, and 'trustworthy' is 'foreign' and name is not
	124	* supported by 'dev', we add a "_%d" suffix based on the minor number
	125	* use that.
	126	*
ca3b6696	127	* If udev is configured, we create a temporary device, open it, and
69207ff6	128	* unlink it.
eca944fa	129	* If not, we create the /dev/mdXX device, and if name is usable,
69207ff6 N	130	* /dev/md/name
	131	* In any case we return /dev/md/name or (if that isn't available)
	132	* /dev/mdXX in 'chosen'.
	133	*
	134	* When we create devices, we use uid/gid/umask from config file.
b5e64645	135	*/
69207ff6 N	136
69207ff6 N	137	int create_mddev(char dev, char name, int autof, int trustworthy,
cd6cbb08	138	char *chosen, int block_udev)
b5e64645 NB	139	{
	140	int mdfd;
	141	struct stat stb;
69207ff6 N	142	int num = -1;
69207ff6 N	143	int use_mdp = -1;
8aec876d	144	struct createinfo *ci = conf_get_create_info();
f1ae21c4	145	int parts;
69207ff6	146	char *cname;
bd1fd72e	147	char devname[37];
4dd2df09	148	char devnm[32];
69207ff6	149	char cbuf[400];
cd6cbb08 N	150
	151	if (!use_udev())
	152	block_udev = 0;
	153
69207ff6 N	154	if (chosen == NULL)
	155	chosen = cbuf;
	156
5bbb4842 NB	157	if (autof == 0)
	158	autof = ci->autof;
	159
f1ae21c4 NB	160	parts = autof >> 3;
	161	autof &= 7;
	162
69207ff6 N	163	strcpy(chosen, "/dev/md/");
	164	cname = chosen + strlen(chosen);
	165
69207ff6	166	if (dev) {
69207ff6 N	167	if (strncmp(dev, "/dev/md/", 8) == 0) {
	168	strcpy(cname, dev+8);
	169	} else if (strncmp(dev, "/dev/", 5) == 0) {
	170	char *e = dev + strlen(dev);
	171	while (e > dev && isdigit(e[-1]))
	172	e--;
	173	if (e[0])
	174	num = strtoul(e, NULL, 10);
	175	strcpy(cname, dev+5);
	176	cname[e-(dev+5)] = 0;
	177	/* name must be mdXX or md_dXX in this context */
	178	if (num < 0 \|\|
	179	(strcmp(cname, "md") != 0 && strcmp(cname, "md_d") != 0)) {
7a862a02	180	pr_err("%s is an invalid name for an md device. Try /dev/md/%s\n",
69207ff6	181	dev, dev+5);
f1ae21c4 NB	182	return -1;
f1ae21c4 NB	183	}
69207ff6 N	184	if (strcmp(cname, "md") == 0)
	185	use_mdp = 0;
	186	else
	187	use_mdp = 1;
11fb4c05 N	188	/* recreate name: /dev/md/0 or /dev/md/d0 */
11fb4c05 N	189	sprintf(cname, "%s%d", use_mdp?"d":"", num);
69207ff6 N	190	} else
	191	strcpy(cname, dev);
	192
11fb4c05 N	193	/* 'cname' must not contain a slash, and may not be
11fb4c05 N	194	* empty.
69207ff6	195	*/
11fb4c05	196	if (strchr(cname, '/') != NULL) {
7a862a02	197	pr_err("%s is an invalid name for an md device.\n", dev);
69207ff6	198	return -1;
f1ae21c4	199	}
11fb4c05	200	if (cname[0] == 0) {
8e5b52cd	201	pr_err("%s is an invalid name for an md device (empty!).\n", dev);
69207ff6	202	return -1;
b5e64645	203	}
11fb4c05 N	204	if (num < 0) {
	205	/* If cname is 'N' or 'dN', we get dev number
	206	* from there.
	207	*/
	208	char *sp = cname;
	209	char *ep;
	210	if (cname[0] == 'd')
	211	sp++;
4cda8682 JM	212	if (isdigit(sp[0]))
	213	num = strtoul(sp, &ep, 10);
	214	else
	215	ep = sp;
11fb4c05 N	216	if (ep == sp \|\| *ep \|\| num < 0)
	217	num = -1;
	218	else if (cname[0] == 'd')
	219	use_mdp = 1;
	220	else
	221	use_mdp = 0;
	222	}
69207ff6	223	}
f1ae21c4	224
69207ff6 N	225	/* Now determine device number */
	226	/* named 'METADATA' cannot use 'mdp'. */
	227	if (name && name[0] == 0)
	228	name = NULL;
	229	if (name && trustworthy == METADATA && use_mdp == 1) {
7a862a02	230	pr_err("%s is not allowed for a %s container. Consider /dev/md%d.\n", dev, name, num);
69207ff6 N	231	return -1;
	232	}
	233	if (name && trustworthy == METADATA)
	234	use_mdp = 0;
	235	if (use_mdp == -1) {
	236	if (autof == 4 \|\| autof == 6)
	237	use_mdp = 1;
f1ae21c4	238	else
69207ff6 N	239	use_mdp = 0;
	240	}
	241	if (num < 0 && trustworthy == LOCAL && name) {
ca3b6696	242	/* if name is numeric, possibly prefixed by
d7ba0c55	243	* 'md' or '/dev/md', use that for num
bde2c6e2	244	* if it is not already in use */
69207ff6	245	char *ep;
d7ba0c55 N	246	char *n2 = name;
	247	if (strncmp(n2, "/dev/", 5) == 0)
	248	n2 += 5;
	249	if (strncmp(n2, "md", 2) == 0)
	250	n2 += 2;
	251	if (*n2 == '/')
	252	n2++;
	253	num = strtoul(n2, &ep, 10);
	254	if (ep == n2 \|\| *ep)
69207ff6	255	num = -1;
4dd2df09 N	256	else {
	257	sprintf(devnm, "md%s%d", use_mdp ? "_d":"", num);
	258	if (mddev_busy(devnm))
	259	num = -1;
	260	}
69207ff6 N	261	}
69207ff6 N	262
69207ff6 N	263	if (cname[0] == 0 && name) {
	264	/* Need to find a name if we can
	265	* We don't completely trust 'name'. Truncate to
	266	* reasonable length and remove '/'
8d80900b	267	*/
69207ff6	268	char *cp;
f2e55ecc N	269	struct map_ent *map = NULL;
	270	int conflict = 1;
	271	int unum = 0;
	272	int cnlen;
69207ff6 N	273	strncpy(cname, name, 200);
69207ff6 N	274	cname[200] = 0;
7103b9b8 N	275	for (cp = cname; *cp ; cp++)
	276	switch (*cp) {
	277	case '/':
	278	*cp = '-';
	279	break;
	280	case ' ':
	281	case '\t':
	282	*cp = '_';
	283	break;
	284	}
	285
f2e55ecc N	286	if (trustworthy == LOCAL \|\|
	287	(trustworthy == FOREIGN && strchr(cname, ':') != NULL)) {
	288	/* Only need suffix if there is a conflict */
	289	if (map_by_name(&map, cname) == NULL)
	290	conflict = 0;
	291	}
	292	cnlen = strlen(cname);
	293	while (conflict) {
add394f3	294	if (trustworthy == METADATA && !isdigit(cname[cnlen-1]))
f2e55ecc N	295	sprintf(cname+cnlen, "%d", unum);
f2e55ecc N	296	else
ca3b6696	297	/* add _%d to FOREIGN array that don't
f2e55ecc N	298	* a 'host:' prefix
	299	*/
	300	sprintf(cname+cnlen, "_%d", unum);
	301	unum++;
	302	if (map_by_name(&map, cname) == NULL)
	303	conflict = 0;
	304	}
69207ff6	305	}
9a40c327	306
eca944fa N	307	devnm[0] = 0;
	308	if (num < 0 && cname && ci->names) {
	309	int fd;
	310	int n = -1;
	311	sprintf(devnm, "md_%s", cname);
cd6cbb08 N	312	if (block_udev)
cd6cbb08 N	313	udev_block(devnm);
eca944fa	314	fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
fdbf7aaa N	315	if (fd < 0 && errno == ENOENT) {
	316	system("modprobe md_mod");
	317	fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
	318	}
eca944fa N	319	if (fd >= 0) {
	320	n = write(fd, devnm, strlen(devnm));
	321	close(fd);
	322	}
cd6cbb08	323	if (n < 0) {
eca944fa	324	devnm[0] = 0;
cd6cbb08 N	325	udev_unblock();
cd6cbb08 N	326	}
eca944fa	327	}
039df362 N	328	if (num >= 0) {
	329	int fd;
	330	int n = -1;
	331	sprintf(devnm, "md%d", num);
cd6cbb08 N	332	if (block_udev)
cd6cbb08 N	333	udev_block(devnm);
039df362 N	334	fd = open("/sys/module/md_mod/parameters/new_array", O_WRONLY);
	335	if (fd >= 0) {
	336	n = write(fd, devnm, strlen(devnm));
	337	close(fd);
	338	}
cd6cbb08	339	if (n < 0) {
039df362	340	devnm[0] = 0;
cd6cbb08	341	udev_unblock();
eca944fa	342	}
cd6cbb08 N	343	}
	344	if (devnm[0] == 0) {
	345	if (num < 0) {
	346	/* need to choose a free number. */
	347	char *_devnm = find_free_devnm(use_mdp);
	348	if (_devnm == NULL) {
	349	pr_err("No avail md devices - aborting\n");
	350	return -1;
	351	}
	352	strcpy(devnm, _devnm);
	353	} else {
	354	sprintf(devnm, "%s%d", use_mdp?"md_d":"md", num);
	355	if (mddev_busy(devnm)) {
	356	pr_err("%s is already in use.\n",
	357	dev);
	358	return -1;
	359	}
eca944fa	360	}
cd6cbb08 N	361	if (block_udev)
cd6cbb08 N	362	udev_block(devnm);
eca944fa N	363	}
	364
	365	sprintf(devname, "/dev/%s", devnm);
	366
5ac6db12	367	if (dev && dev[0] == '/')
9a40c327 N	368	strcpy(chosen, dev);
9a40c327 N	369	else if (cname[0] == 0)
69207ff6	370	strcpy(chosen, devname);
8d80900b	371
69207ff6	372	/* We have a device number and name.
11fb4c05 N	373	* If we cannot detect udev, we need to make
11fb4c05 N	374	* devices and links ourselves.
69207ff6	375	*/
06d2ffc3	376	if (!use_udev()) {
69207ff6 N	377	/* Make sure 'devname' exists and 'chosen' is a symlink to it */
	378	if (lstat(devname, &stb) == 0) {
	379	/* Must be the correct device, else error */
	380	if ((stb.st_mode&S_IFMT) != S_IFBLK \|\|
13db17bd	381	stb.st_rdev != devnm2devid(devnm)) {
e7b84f9d	382	pr_err("%s exists but looks wrong, please fix\n",
69207ff6 N	383	devname);
69207ff6 N	384	return -1;
0a6e1c67	385	}
69207ff6 N	386	} else {
69207ff6 N	387	if (mknod(devname, S_IFBLK\|0600,
4dd2df09	388	devnm2devid(devnm)) != 0) {
e7b84f9d	389	pr_err("failed to create %s\n",
69207ff6	390	devname);
b5e64645 NB	391	return -1;
b5e64645 NB	392	}
69207ff6 N	393	if (chown(devname, ci->uid, ci->gid))
	394	perror("chown");
	395	if (chmod(devname, ci->mode))
	396	perror("chmod");
	397	stat(devname, &stb);
	398	add_dev(devname, &stb, 0, NULL);
	399	}
c4fe2d4f N	400	if (use_mdp == 1)
c4fe2d4f N	401	make_parts(devname, parts);
69207ff6	402
ca3b6696 N	403	if (strcmp(chosen, devname) != 0) {
ca3b6696 N	404	if (mkdir("/dev/md",0700) == 0) {
69207ff6 N	405	if (chown("/dev/md", ci->uid, ci->gid))
	406	perror("chown /dev/md");
	407	if (chmod("/dev/md", ci->mode\| ((ci->mode>>2) & 0111)))
	408	perror("chmod /dev/md");
8d80900b	409	}
69207ff6 N	410
	411	if (dev && strcmp(chosen, dev) == 0)
	412	/* We know we are allowed to use this name */
	413	unlink(chosen);
	414
	415	if (lstat(chosen, &stb) == 0) {
	416	char buf[300];
fca13185 TJ	417	ssize_t link_len = readlink(chosen, buf, sizeof(buf)-1);
	418	if (link_len >= 0)
	419	buf[link_len] = '\0';
	420
69207ff6	421	if ((stb.st_mode & S_IFMT) != S_IFLNK \|\|
fca13185	422	link_len < 0 \|\|
69207ff6	423	strcmp(buf, devname) != 0) {
e7b84f9d	424	pr_err("%s exists - ignoring\n",
69207ff6 N	425	chosen);
	426	strcpy(chosen, devname);
	427	}
614825ea	428	} else if (symlink(devname, chosen) != 0)
e7b84f9d	429	pr_err("failed to create %s: %s\n",
614825ea	430	chosen, strerror(errno));
c4fe2d4f N	431	if (use_mdp && strcmp(chosen, devname) != 0)
c4fe2d4f N	432	make_parts(chosen, parts);
b5e64645	433	}
b5e64645	434	}
4dd2df09	435	mdfd = open_dev_excl(devnm);
69207ff6	436	if (mdfd < 0)
e7b84f9d	437	pr_err("unexpected failure opening %s\n",
69207ff6	438	devname);
6be1d39d N	439	return mdfd;
	440	}
	441
	442	/* Open this and check that it is an md device.
	443	* On success, return filedescriptor.
	444	* On failure, return -1 if it doesn't exist,
	445	* or -2 if it exists but is not an md device.
	446	*/
	447	int open_mddev(char *dev, int report_errors)
	448	{
f71d2b8f	449	int mdfd = open(dev, O_RDONLY);
40b054e1	450
6be1d39d N	451	if (mdfd < 0) {
6be1d39d N	452	if (report_errors)
e7b84f9d	453	pr_err("error opening %s: %s\n",
6be1d39d N	454	dev, strerror(errno));
	455	return -1;
	456	}
40b054e1	457
9db2ab4e	458	if (md_array_valid(mdfd) == 0) {
b5e64645	459	close(mdfd);
6be1d39d	460	if (report_errors)
7a862a02	461	pr_err("%s does not appear to be an md device\n", dev);
6be1d39d	462	return -2;
b5e64645	463	}
40b054e1	464
b5e64645 NB	465	return mdfd;
b5e64645 NB	466	}
289c74f8 N	467
	468	char *find_free_devnm(int use_partitions)
	469	{
	470	static char devnm[32];
	471	int devnum;
	472	for (devnum = 127; devnum != 128;
2e466cce	473	devnum = devnum ? devnum-1 : (1<<9)-1) {
289c74f8 N	474
	475	if (use_partitions)
	476	sprintf(devnm, "md_d%d", devnum);
	477	else
	478	sprintf(devnm, "md%d", devnum);
	479	if (mddev_busy(devnm))
	480	continue;
	481	if (!conf_name_is_free(devnm))
	482	continue;
	483	if (!use_udev()) {
	484	/* make sure it is new to /dev too, at least as a
	485	* non-standard */
13db17bd	486	dev_t devid = devnm2devid(devnm);
289c74f8 N	487	if (devid) {
	488	char *dn = map_dev(major(devid),
	489	minor(devid), 0);
	490	if (dn && ! is_standard(dn, NULL))
	491	continue;
	492	}
	493	}
	494	break;
	495	}
	496	if (devnum == 128)
	497	return NULL;
	498	return devnm;
	499	}