[thirdparty/mdadm.git] / mdopen.c

/*
 * mdadm - manage Linux "md" devices aka RAID arrays.
 *
 * Copyright (C) 2001-2006 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@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'
	 * 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 = major_num; /* quiet gcc -Os unitialized warning */
	int minor_num = minor_num; /* quiet gcc -Os unitialized warning */
	int odig = odig; /* quiet gcc -Os unitialized warning */
	int i;
	int nlen = strlen(dev) + 20;
	char *name = malloc(nlen);
	int dig = isdigit(dev[strlen(dev)-1]);
	char orig[1024];
	char sym[1024];

	if (cnt==0) cnt=4;
	if (lstat(dev, &stb)!= 0)
		return;
	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]);
	} else if (S_ISBLK(stb.st_mode)) {
		major_num = major(stb.st_rdev);
		minor_num = minor(stb.st_rdev);
	} else
		   return;
	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_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");
		} else {
			snprintf(sym, 10000, "%s%s%d", orig, odig?"p":"", i);
			symlink(sym, name);
		}
		stat(name, &stb2);
		add_dev(name, &stb2, 0, NULL);
	}
}


/*
 * 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, char *name, int autof, int trustworthy,
		 char *chosen)
{
	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[20];
	char cbuf[400];
	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)) {
				fprintf(stderr, Name ": %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) {
			fprintf(stderr, Name ": %s is an invalid name "
				"for an md device.\n", dev);
			return -1;
		}
		if (cname[0] == 0) {
			fprintf(stderr, Name ": %s is an invalid name "
				"for an md device (empty!).", 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++;
			num = strtoul(sp, &ep, 10);
			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) {
		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
			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 (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 '/'
		 */
		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 cannot detect udev, we need to make
	 * devices and links ourselves.
	 */
	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;
			}
		} 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 (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];
				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);
			if (use_mdp && strcmp(chosen, devname) != 0)
				make_parts(chosen, parts);
		}
	}
	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,
 * or -2 if it exists but is not an md device.
 */
int open_mddev(char *dev, int report_errors)
{
	int mdfd = open(dev, O_RDWR);
	if (mdfd < 0) {
		if (report_errors)
			fprintf(stderr, Name ": error opening %s: %s\n",
				dev, strerror(errno));
		return -1;
	}
	if (md_get_version(mdfd) <= 0) {
		close(mdfd);
		if (report_errors)
			fprintf(stderr, Name ": %s does not appear to be "
				"an md device\n", dev);
		return -2;
	}
	return mdfd;
}
Commit	Line	Data
b5e64645 NB	1	/*
	2	* mdadm - manage Linux "md" devices aka RAID arrays.
	3	*
4f589ad0	4	* Copyright (C) 2001-2006 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
	22	* Email: <neilb@cse.unsw.edu.au>
	23	* Paper: Neil Brown
	24	* School of Computer Science and Engineering
	25	* The University of New South Wales
	26	* Sydney, 2052
	27	* Australia
	28	*/
	29
	30	#include "mdadm.h"
	31	#include "md_p.h"
	32	#include <ctype.h>
	33
0a6e1c67	34
c4fe2d4f	35	void make_parts(char *dev, int cnt)
b5e64645 NB	36	{
b5e64645 NB	37	/* make 'cnt' partition devices for 'dev'
c4fe2d4f N	38	* If dev is a device name we use the
	39	* major/minor from dev and add 1..cnt
	40	* If it is a symlink, we make similar symlinks.
8d80900b	41	* If dev ends with a digit, we add "p%d" else "%d"
b5e64645 NB	42	* If the name exists, we use it's owner/mode,
	43	* else that of dev
	44	*/
	45	struct stat stb;
197e3eb6 DW	46	int major_num = major_num; /* quiet gcc -Os unitialized warning */
	47	int minor_num = minor_num; /* quiet gcc -Os unitialized warning */
	48	int odig = odig; /* quiet gcc -Os unitialized warning */
b5e64645	49	int i;
8f23b0b3 NB	50	int nlen = strlen(dev) + 20;
8f23b0b3 NB	51	char *name = malloc(nlen);
b5e64645	52	int dig = isdigit(dev[strlen(dev)-1]);
c4fe2d4f N	53	char orig[1024];
c4fe2d4f N	54	char sym[1024];
b5e64645	55
f1ae21c4	56	if (cnt==0) cnt=4;
c4fe2d4f	57	if (lstat(dev, &stb)!= 0)
b5e64645	58	return;
c4fe2d4f N	59	if (S_ISLNK(stb.st_mode)) {
	60	int len = readlink(dev, orig, sizeof(orig));
	61	if (len < 0 \|\| len > 1000)
	62	return;
	63	orig[len] = 0;
	64	odig = isdigit(orig[len-1]);
	65	} else if (S_ISBLK(stb.st_mode)) {
	66	major_num = major(stb.st_rdev);
	67	minor_num = minor(stb.st_rdev);
	68	} else
	69	return;
b5e64645 NB	70	for (i=1; i <= cnt ; i++) {
b5e64645 NB	71	struct stat stb2;
8f23b0b3	72	snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i);
b5e64645 NB	73	if (stat(name, &stb2)==0) {
	74	if (!S_ISBLK(stb2.st_mode))
	75	continue;
b440882e	76	if (stb2.st_rdev == makedev(major_num, minor_num+i))
b5e64645 NB	77	continue;
	78	unlink(name);
	79	} else {
	80	stb2 = stb;
	81	}
c4fe2d4f N	82	if (S_ISBLK(stb.st_mode)) {
	83	if (mknod(name, S_IFBLK \| 0600,
	84	makedev(major_num, minor_num+i)))
	85	perror("mknod");
	86	if (chown(name, stb2.st_uid, stb2.st_gid))
	87	perror("chown");
	88	if (chmod(name, stb2.st_mode & 07777))
	89	perror("chmod");
	90	} else {
	91	snprintf(sym, 10000, "%s%s%d", orig, odig?"p":"", i);
	92	symlink(sym, name);
	93	}
173fc515 NB	94	stat(name, &stb2);
173fc515 NB	95	add_dev(name, &stb2, 0, NULL);
b5e64645 NB	96	}
	97	}
	98
0a6e1c67	99
b5e64645	100	/*
69207ff6 N	101	* We need a new md device to assemble/build/create an array.
	102	* 'dev' is a name given us by the user (command line or mdadm.conf)
	103	* It might start with /dev or /dev/md any might end with a digit
	104	* string.
	105	* If it starts with just /dev, it must be /dev/mdX or /dev/md_dX
	106	* If it ends with a digit string, then it must be as above, or
	107	* 'trustworthy' must be 'METADATA' and the 'dev' must be
	108	* /dev/md/'name'NN or 'name'NN
	109	* If it doesn't end with a digit string, it must be /dev/md/'name'
	110	* or 'name' or must be NULL.
	111	* If the digit string is present, it gives the minor number to use
	112	* If not, we choose a high, unused minor number.
	113	* If the 'dev' is a standard name, it devices whether 'md' or 'mdp'.
	114	* else if the name is 'd[0-9]+' then we use mdp
	115	* else if trustworthy is 'METADATA' we use md
	116	* else the choice depends on 'autof'.
	117	* If name is NULL it is assumed to match whatever dev provides.
	118	* If both name and dev are NULL, we choose a name 'mdXX' or 'mdpXX'
	119	*
	120	* If 'name' is given, and 'trustworthy' is 'foreign' and name is not
	121	* supported by 'dev', we add a "_%d" suffix based on the minor number
	122	* use that.
	123	*
	124	* If udev is configured, we create a temporary device, open it, and
	125	* unlink it.
	126	* If not, we create the /dev/mdXX device, and is name is usable,
	127	* /dev/md/name
	128	* In any case we return /dev/md/name or (if that isn't available)
	129	* /dev/mdXX in 'chosen'.
	130	*
	131	* When we create devices, we use uid/gid/umask from config file.
b5e64645	132	*/
69207ff6 N	133
	134	int create_mddev(char dev, char name, int autof, int trustworthy,
	135	char *chosen)
b5e64645 NB	136	{
	137	int mdfd;
	138	struct stat stb;
69207ff6 N	139	int num = -1;
69207ff6 N	140	int use_mdp = -1;
8aec876d	141	struct createinfo *ci = conf_get_create_info();
f1ae21c4	142	int parts;
69207ff6 N	143	char *cname;
	144	char devname[20];
	145	char cbuf[400];
	146	if (chosen == NULL)
	147	chosen = cbuf;
	148
b5e64645	149
5bbb4842 NB	150	if (autof == 0)
	151	autof = ci->autof;
	152
f1ae21c4 NB	153	parts = autof >> 3;
	154	autof &= 7;
	155
69207ff6 N	156	strcpy(chosen, "/dev/md/");
	157	cname = chosen + strlen(chosen);
	158
	159
	160	if (dev) {
	161
	162	if (strncmp(dev, "/dev/md/", 8) == 0) {
	163	strcpy(cname, dev+8);
	164	} else if (strncmp(dev, "/dev/", 5) == 0) {
	165	char *e = dev + strlen(dev);
	166	while (e > dev && isdigit(e[-1]))
	167	e--;
	168	if (e[0])
	169	num = strtoul(e, NULL, 10);
	170	strcpy(cname, dev+5);
	171	cname[e-(dev+5)] = 0;
	172	/* name must be mdXX or md_dXX in this context */
	173	if (num < 0 \|\|
	174	(strcmp(cname, "md") != 0 && strcmp(cname, "md_d") != 0)) {
	175	fprintf(stderr, Name ": %s is an invalid name "
	176	"for an md device. Try /dev/md/%s\n",
	177	dev, dev+5);
f1ae21c4 NB	178	return -1;
f1ae21c4 NB	179	}
69207ff6 N	180	if (strcmp(cname, "md") == 0)
	181	use_mdp = 0;
	182	else
	183	use_mdp = 1;
11fb4c05 N	184	/* recreate name: /dev/md/0 or /dev/md/d0 */
11fb4c05 N	185	sprintf(cname, "%s%d", use_mdp?"d":"", num);
69207ff6 N	186	} else
	187	strcpy(cname, dev);
	188
11fb4c05 N	189	/* 'cname' must not contain a slash, and may not be
11fb4c05 N	190	* empty.
69207ff6	191	*/
11fb4c05	192	if (strchr(cname, '/') != NULL) {
69207ff6 N	193	fprintf(stderr, Name ": %s is an invalid name "
	194	"for an md device.\n", dev);
	195	return -1;
f1ae21c4	196	}
11fb4c05	197	if (cname[0] == 0) {
69207ff6 N	198	fprintf(stderr, Name ": %s is an invalid name "
	199	"for an md device (empty!).", dev);
	200	return -1;
b5e64645	201	}
11fb4c05 N	202	if (num < 0) {
	203	/* If cname is 'N' or 'dN', we get dev number
	204	* from there.
	205	*/
	206	char *sp = cname;
	207	char *ep;
	208	if (cname[0] == 'd')
	209	sp++;
	210	num = strtoul(sp, &ep, 10);
	211	if (ep == sp \|\| *ep \|\| num < 0)
	212	num = -1;
	213	else if (cname[0] == 'd')
	214	use_mdp = 1;
	215	else
	216	use_mdp = 0;
	217	}
69207ff6	218	}
f1ae21c4	219
69207ff6 N	220	/* Now determine device number */
	221	/* named 'METADATA' cannot use 'mdp'. */
	222	if (name && name[0] == 0)
	223	name = NULL;
	224	if (name && trustworthy == METADATA && use_mdp == 1) {
	225	fprintf(stderr, Name ": %s is not allowed for a %s container. "
	226	"Consider /dev/md%d.\n", dev, name, num);
	227	return -1;
	228	}
	229	if (name && trustworthy == METADATA)
	230	use_mdp = 0;
	231	if (use_mdp == -1) {
	232	if (autof == 4 \|\| autof == 6)
	233	use_mdp = 1;
f1ae21c4	234	else
69207ff6 N	235	use_mdp = 0;
	236	}
	237	if (num < 0 && trustworthy == LOCAL && name) {
	238	/* if name is numeric, us that for num */
	239	char *ep;
	240	num = strtoul(name, &ep, 10);
	241	if (ep == name \|\| *ep)
	242	num = -1;
	243	}
	244
	245	if (num < 0) {
	246	/* need to choose a free number. */
	247	num = find_free_devnum(use_mdp);
	248	if (num == NoMdDev) {
	249	fprintf(stderr, Name ": No avail md devices - aborting\n");
	250	return -1;
	251	}
	252	} else {
	253	num = use_mdp ? (-1-num) : num;
	254	if (mddev_busy(num)) {
	255	fprintf(stderr, Name ": %s is already in use.\n",
	256	dev);
	257	return -1;
	258	}
	259	}
	260
	261	if (num < 0)
	262	sprintf(devname, "/dev/md_d%d", -1-num);
	263	else
	264	sprintf(devname, "/dev/md%d", num);
f1ae21c4	265
69207ff6 N	266	if (cname[0] == 0 && name) {
	267	/* Need to find a name if we can
	268	* We don't completely trust 'name'. Truncate to
	269	* reasonable length and remove '/'
8d80900b	270	*/
69207ff6 N	271	char *cp;
	272	strncpy(cname, name, 200);
	273	cname[200] = 0;
	274	while ((cp = strchr(cname, '/')) != NULL)
	275	*cp = '-';
	276	if (trustworthy == METADATA)
	277	/* always add device number to metadata */
	278	sprintf(cname+strlen(cname), "%d", num);
	279	else if (trustworthy == FOREIGN &&
	280	strchr(cname, ':') == NULL)
	281	/* add _%d to FOREIGN array that don't have
	282	* a 'host:' prefix
	283	*/
	284	sprintf(cname+strlen(cname), "_%d", num<0?(-1-num):num);
	285	}
	286	if (cname[0] == 0)
	287	strcpy(chosen, devname);
8d80900b	288
69207ff6	289	/* We have a device number and name.
11fb4c05 N	290	* If we cannot detect udev, we need to make
11fb4c05 N	291	* devices and links ourselves.
69207ff6 N	292	*/
	293	if (stat("/dev/.udev", &stb) != 0 \|\|
	294	check_env("MDADM_NO_UDEV")) {
	295	/* Make sure 'devname' exists and 'chosen' is a symlink to it */
	296	if (lstat(devname, &stb) == 0) {
	297	/* Must be the correct device, else error */
	298	if ((stb.st_mode&S_IFMT) != S_IFBLK \|\|
	299	stb.st_rdev != makedev(dev2major(num),dev2minor(num))) {
	300	fprintf(stderr, Name ": %s exists but looks wrong, please fix\n",
	301	devname);
	302	return -1;
0a6e1c67	303	}
69207ff6 N	304	} else {
	305	if (mknod(devname, S_IFBLK\|0600,
	306	makedev(dev2major(num),dev2minor(num))) != 0) {
	307	fprintf(stderr, Name ": failed to create %s\n",
	308	devname);
b5e64645 NB	309	return -1;
b5e64645 NB	310	}
69207ff6 N	311	if (chown(devname, ci->uid, ci->gid))
	312	perror("chown");
	313	if (chmod(devname, ci->mode))
	314	perror("chmod");
	315	stat(devname, &stb);
	316	add_dev(devname, &stb, 0, NULL);
	317	}
c4fe2d4f N	318	if (use_mdp == 1)
c4fe2d4f N	319	make_parts(devname, parts);
69207ff6 N	320	if (strcmp(chosen, devname) != 0) {
	321
	322	if (mkdir("/dev/md",0700)==0) {
	323	if (chown("/dev/md", ci->uid, ci->gid))
	324	perror("chown /dev/md");
	325	if (chmod("/dev/md", ci->mode\| ((ci->mode>>2) & 0111)))
	326	perror("chmod /dev/md");
8d80900b	327	}
69207ff6 N	328
	329	if (dev && strcmp(chosen, dev) == 0)
	330	/* We know we are allowed to use this name */
	331	unlink(chosen);
	332
	333	if (lstat(chosen, &stb) == 0) {
	334	char buf[300];
	335	if ((stb.st_mode & S_IFMT) != S_IFLNK \|\|
	336	readlink(chosen, buf, 300) <0 \|\|
	337	strcmp(buf, devname) != 0) {
	338	fprintf(stderr, Name ": %s exists - ignoring\n",
	339	chosen);
	340	strcpy(chosen, devname);
	341	}
	342	} else
	343	symlink(devname, chosen);
c4fe2d4f N	344	if (use_mdp && strcmp(chosen, devname) != 0)
c4fe2d4f N	345	make_parts(chosen, parts);
b5e64645	346	}
b5e64645	347	}
69207ff6 N	348	mdfd = open_dev_excl(num);
	349	if (mdfd < 0)
	350	fprintf(stderr, Name ": unexpected failure opening %s\n",
	351	devname);
6be1d39d N	352	return mdfd;
	353	}
	354
69207ff6	355
6be1d39d N	356	/* Open this and check that it is an md device.
	357	* On success, return filedescriptor.
	358	* On failure, return -1 if it doesn't exist,
	359	* or -2 if it exists but is not an md device.
	360	*/
	361	int open_mddev(char *dev, int report_errors)
	362	{
	363	int mdfd = open(dev, O_RDWR);
	364	if (mdfd < 0) {
	365	if (report_errors)
	366	fprintf(stderr, Name ": error opening %s: %s\n",
	367	dev, strerror(errno));
	368	return -1;
	369	}
	370	if (md_get_version(mdfd) <= 0) {
b5e64645	371	close(mdfd);
6be1d39d N	372	if (report_errors)
	373	fprintf(stderr, Name ": %s does not appear to be "
	374	"an md device\n", dev);
	375	return -2;
b5e64645 NB	376	}
	377	return mdfd;
	378	}