[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'
	 * 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;
	int nlen = strlen(dev) + 20;
	char *name = malloc(nlen);
	int dig = isdigit(dev[strlen(dev)-1]);

	if (cnt==0) cnt=4;
	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;
		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, minor+i))
				continue;
			unlink(name);
		} else {
			stb2 = stb;
		}
		if (mknod(name, S_IFBLK | 0600, makedev(major, minor+i)))
			perror("mknod");
		if (chown(name, stb2.st_uid, stb2.st_gid))
			perror("chown");
		if (chmod(name, stb2.st_mode & 07777))
			perror("chmod");
		stat(name, &stb2);
		add_dev(name, &stb2, 0, NULL);
	}
}

/*
 * 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.
 */
int open_mddev(char *dev, int autof)
{
	int mdfd;
	struct stat stb;
	int major = MD_MAJOR;
	int minor = 0;
	int must_remove = 0;
	struct mdstat_ent *mdlist;
	int num;
	struct createinfo *ci = conf_get_create_info();
	int parts;

	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;
		}
		if (autof == 2 && stb.st_mode == 0 && !is_standard(dev, NULL)) {
			fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\n", dev);
			return -1;
		}
		/* check major number is correct */
		num = -1;
		std = is_standard(dev, &num);
		if (std>0) major = get_mdp_major();
		switch(autof) {
		case 2: /* only create is_standard names */
			if (!std && !stb.st_mode) {
				fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\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);
				return -1;
			}
			break;
		case 5: /* default to md if not standard */
			break;
		case 6: /* default to mdp if not standard */
			if (std == 0) major = get_mdp_major();
			break;
		}
		/* major is final. num is -1 if not standard */
		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 */
				close(mdfd);
				fprintf(stderr, Name ": %s is already active.\n",
					dev);
				return -1;
			} else {
				if (major != MD_MAJOR && parts > 0)
					make_parts(dev, parts);
				return mdfd;
			}
		}
		/* 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 */
			mdlist = mdstat_read(0, 0);
			/* Choose a large number.  Start from 127 and search down,
			 * but if nothing is found, start really big
			 */
			for (num = 127 ; num != 128 ; num = num ? num-1 : (1<<22)-1) {
				struct mdstat_ent *me;
				int devnum = num;
				if (major != MD_MAJOR)
					devnum = -1-num;

				for (me=mdlist; me; me=me->next)
					if (me->devnum == devnum)
						break;
				if (!me) {
					/* doesn't exist in mdstat.
					 * make sure it is new to /dev too
					 */
					char *dn;
					if (major != MD_MAJOR)
						minor = num << MdpMinorShift;
					else
						minor = num;
					dn = map_dev(major,minor, 0);
					if (dn==NULL || is_standard(dn, NULL)) {
						/* this number only used by a 'standard' name,
						 * so it is safe to use
						 */
						break;
					}
				}
			}
		} else if (major == MD_MAJOR)
			minor = num;
		else
			minor = num << MdpMinorShift;
		/* major and minor have been chosen */

		/* If it was a 'standard' name and it is in-use, then
		 * the device could already be correct
		 */
		if (stb.st_mode && major(stb.st_rdev) == major &&
		    minor(stb.st_rdev) == minor)
			;
		else {
			if (major(makedev(major,minor)) != major ||
			    minor(makedev(major,minor)) != minor) {
				fprintf(stderr, Name ": Need newer C library to use more than 4 partitionable md devices, sorry\n");
				return -1;
			}
			if (must_remove)
				unlink(dev);

			if (mknod(dev, S_IFBLK|0600, makedev(major, minor))!= 0) {
				fprintf(stderr, Name ": failed to create %s\n", dev);
				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");
			}
			stat(dev, &stb);
			add_dev(dev, &stb, 0, NULL);
			if (major != MD_MAJOR)
				make_parts(dev,parts);
		}
	}
	mdfd = open(dev, O_RDWR, 0);
	if (mdfd < 0)
		fprintf(stderr, Name ": error opening %s: %s\n",
			dev, strerror(errno));
	else if (md_get_version(mdfd) <= 0) {
		fprintf(stderr, Name ": %s does not appear to be an md device\n",
			dev);
		close(mdfd);
		mdfd = -1;
	}
	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
	34	void make_parts(char *dev, int cnt)
	35	{
	36	/* make 'cnt' partition devices for 'dev'
	37	* We use the major/minor from dev and add 1..cnt
8d80900b	38	* If dev ends with a digit, we add "p%d" else "%d"
b5e64645 NB	39	* If the name exists, we use it's owner/mode,
	40	* else that of dev
	41	*/
	42	struct stat stb;
	43	int major, minor;
	44	int i;
8f23b0b3 NB	45	int nlen = strlen(dev) + 20;
8f23b0b3 NB	46	char *name = malloc(nlen);
b5e64645 NB	47	int dig = isdigit(dev[strlen(dev)-1]);
b5e64645 NB	48
f1ae21c4	49	if (cnt==0) cnt=4;
b5e64645 NB	50	if (stat(dev, &stb)!= 0)
	51	return;
	52	if (!S_ISBLK(stb.st_mode))
	53	return;
0df46c2a NB	54	major = major(stb.st_rdev);
0df46c2a NB	55	minor = minor(stb.st_rdev);
b5e64645 NB	56	for (i=1; i <= cnt ; i++) {
b5e64645 NB	57	struct stat stb2;
8f23b0b3	58	snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i);
b5e64645 NB	59	if (stat(name, &stb2)==0) {
	60	if (!S_ISBLK(stb2.st_mode))
	61	continue;
0df46c2a	62	if (stb2.st_rdev == makedev(major, minor+i))
b5e64645 NB	63	continue;
	64	unlink(name);
	65	} else {
	66	stb2 = stb;
	67	}
1e0d770c NB	68	if (mknod(name, S_IFBLK \| 0600, makedev(major, minor+i)))
	69	perror("mknod");
	70	if (chown(name, stb2.st_uid, stb2.st_gid))
	71	perror("chown");
	72	if (chmod(name, stb2.st_mode & 07777))
	73	perror("chmod");
173fc515 NB	74	stat(name, &stb2);
173fc515 NB	75	add_dev(name, &stb2, 0, NULL);
b5e64645 NB	76	}
	77	}
	78
	79	/*
	80	* Open a given md device, and check that it really is one.
	81	* If 'autof' is given, then we need to create, or recreate, the md device.
	82	* If the name already exists, and is not a block device, we fail.
	83	* If it exists and is not an md device, is not the right type (partitioned or not),
	84	* or is currently in-use, we remove the device, but remember the owner and mode.
8d80900b	85	* If it now doesn't exist, we find a new md array and create the device.
5bbb4842	86	* Default ownership/mode comes from config file.
b5e64645 NB	87	*/
	88	int open_mddev(char *dev, int autof)
	89	{
	90	int mdfd;
	91	struct stat stb;
	92	int major = MD_MAJOR;
a0ef61bf	93	int minor = 0;
b5e64645 NB	94	int must_remove = 0;
	95	struct mdstat_ent *mdlist;
	96	int num;
8aec876d	97	struct createinfo *ci = conf_get_create_info();
f1ae21c4	98	int parts;
b5e64645	99
5bbb4842 NB	100	if (autof == 0)
	101	autof = ci->autof;
	102
f1ae21c4 NB	103	parts = autof >> 3;
	104	autof &= 7;
	105
	106	if (autof && autof != 1) {
b5e64645 NB	107	/* autof is set, so we need to check that the name is ok,
	108	* and possibly create one if not
	109	*/
f1ae21c4	110	int std;
b5e64645	111	stb.st_mode = 0;
0bbc98b5	112	if (stat(dev, &stb)==0 && ! S_ISBLK(stb.st_mode)) {
b5e64645 NB	113	fprintf(stderr, Name ": %s is not a block device.\n",
	114	dev);
	115	return -1;
	116	}
f1ae21c4 NB	117	if (autof == 2 && stb.st_mode == 0 && !is_standard(dev, NULL)) {
	118	fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\n", dev);
	119	return -1;
	120	}
b5e64645	121	/* check major number is correct */
f1ae21c4 NB	122	num = -1;
	123	std = is_standard(dev, &num);
	124	if (std>0) major = get_mdp_major();
	125	switch(autof) {
	126	case 2: /* only create is_standard names */
	127	if (!std && !stb.st_mode) {
	128	fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\n", dev);
	129	return -1;
	130	}
	131	break;
	132	case 3: /* create md, reject std>0 */
	133	if (std > 0) {
	134	fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
	135	return -1;
	136	}
	137	break;
	138	case 4: /* create mdp, reject std<0 */
	139	if (std < 0) {
	140	fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
	141	return -1;
	142	}
	143	break;
	144	case 5: /* default to md if not standard */
	145	break;
	146	case 6: /* default to mdp if not standard */
	147	if (std == 0) major = get_mdp_major();
	148	break;
	149	}
	150	/* major is final. num is -1 if not standard */
0df46c2a	151	if (stb.st_mode && major(stb.st_rdev) != major)
b5e64645 NB	152	must_remove = 1;
	153	if (stb.st_mode && !must_remove) {
	154	mdu_array_info_t array;
	155	/* looks ok, see if it is available */
	156	mdfd = open(dev, O_RDWR, 0);
	157	if (mdfd < 0) {
	158	fprintf(stderr, Name ": error opening %s: %s\n",
	159	dev, strerror(errno));
	160	return -1;
	161	} else if (md_get_version(mdfd) <= 0) {
	162	fprintf(stderr, Name ": %s does not appear to be an md device\n",
	163	dev);
	164	close(mdfd);
	165	return -1;
	166	}
	167	if (ioctl(mdfd, GET_ARRAY_INFO, &array)==0) {
	168	/* already active */
b5e64645	169	close(mdfd);
d55e3aef	170	fprintf(stderr, Name ": %s is already active.\n",
2e2642f2 NB	171	dev);
2e2642f2 NB	172	return -1;
b5e64645	173	} else {
f1ae21c4 NB	174	if (major != MD_MAJOR && parts > 0)
f1ae21c4 NB	175	make_parts(dev, parts);
b5e64645 NB	176	return mdfd;
	177	}
	178	}
	179	/* Ok, need to find a minor that is not in use.
8d80900b NB	180	* If the device name is in a 'standard' format,
	181	* intuit the minor from that, else
	182	* easiest to read /proc/mdstat, and hunt through for
b5e64645 NB	183	* an unused number
b5e64645 NB	184	*/
f1ae21c4 NB	185	if (num < 0) {
f1ae21c4 NB	186	/* need to pick an unused number */
22a88995	187	mdlist = mdstat_read(0, 0);
e7bb5d23 NB	188	/* Choose a large number. Start from 127 and search down,
	189	* but if nothing is found, start really big
	190	*/
	191	for (num = 127 ; num != 128 ; num = num ? num-1 : (1<<22)-1) {
8d80900b	192	struct mdstat_ent *me;
f1ae21c4 NB	193	int devnum = num;
	194	if (major != MD_MAJOR)
	195	devnum = -1-num;
	196
8d80900b	197	for (me=mdlist; me; me=me->next)
f1ae21c4	198	if (me->devnum == devnum)
8d80900b NB	199	break;
8d80900b NB	200	if (!me) {
e7bb5d23	201	/* doesn't exist in mdstat.
8d80900b	202	* make sure it is new to /dev too
b5e64645	203	*/
8d80900b	204	char *dn;
f1ae21c4 NB	205	if (major != MD_MAJOR)
f1ae21c4 NB	206	minor = num << MdpMinorShift;
8d80900b NB	207	else
8d80900b NB	208	minor = num;
16c6fa80	209	dn = map_dev(major,minor, 0);
8d80900b NB	210	if (dn==NULL \|\| is_standard(dn, NULL)) {
	211	/* this number only used by a 'standard' name,
	212	* so it is safe to use
	213	*/
	214	break;
	215	}
b5e64645 NB	216	}
b5e64645 NB	217	}
f1ae21c4 NB	218	} else if (major == MD_MAJOR)
	219	minor = num;
	220	else
	221	minor = num << MdpMinorShift;
8d80900b	222	/* major and minor have been chosen */
f1ae21c4	223
8d80900b NB	224	/* If it was a 'standard' name and it is in-use, then
	225	* the device could already be correct
	226	*/
0df46c2a NB	227	if (stb.st_mode && major(stb.st_rdev) == major &&
0df46c2a NB	228	minor(stb.st_rdev) == minor)
8d80900b NB	229	;
8d80900b NB	230	else {
0df46c2a NB	231	if (major(makedev(major,minor)) != major \|\|
	232	minor(makedev(major,minor)) != minor) {
	233	fprintf(stderr, Name ": Need newer C library to use more than 4 partitionable md devices, sorry\n");
	234	return -1;
	235	}
8d80900b NB	236	if (must_remove)
	237	unlink(dev);
	238
0df46c2a	239	if (mknod(dev, S_IFBLK\|0600, makedev(major, minor))!= 0) {
8d80900b	240	fprintf(stderr, Name ": failed to create %s\n", dev);
b5e64645 NB	241	return -1;
b5e64645 NB	242	}
8d80900b	243	if (must_remove) {
1e0d770c NB	244	if (chown(dev, stb.st_uid, stb.st_gid))
	245	perror("chown");
	246	if (chmod(dev, stb.st_mode & 07777))
	247	perror("chmod");
5bbb4842 NB	248	} else {
	249	if (chown(dev, ci->uid, ci->gid))
	250	perror("chown");
	251	if (chmod(dev, ci->mode))
	252	perror("chmod");
8d80900b	253	}
173fc515 NB	254	stat(dev, &stb);
173fc515 NB	255	add_dev(dev, &stb, 0, NULL);
f1ae21c4 NB	256	if (major != MD_MAJOR)
f1ae21c4 NB	257	make_parts(dev,parts);
b5e64645	258	}
b5e64645 NB	259	}
	260	mdfd = open(dev, O_RDWR, 0);
	261	if (mdfd < 0)
	262	fprintf(stderr, Name ": error opening %s: %s\n",
	263	dev, strerror(errno));
	264	else if (md_get_version(mdfd) <= 0) {
	265	fprintf(stderr, Name ": %s does not appear to be an md device\n",
	266	dev);
	267	close(mdfd);
	268	mdfd = -1;
	269	}
	270	return mdfd;
	271	}
	272