X-Git-Url: http://git.ipfire.org/?a=blobdiff_plain;f=mdopen.c;h=b4d7bdc0ee263324030fc222d74685247cf7aec2;hb=78b958e2052ccd069fa6ccc2367cda758d55540e;hp=721d74ae042053f905ebcc2a9443dfea4449b34f;hpb=0bbc98b563b39b5159d247a0a4d6e8e1e6e38c30;p=thirdparty%2Fmdadm.git

diff --git a/mdopen.c b/mdopen.c
index 721d74ae..b4d7bdc0 100644
--- a/mdopen.c
+++ b/mdopen.c
@@ -1,7 +1,7 @@
 /*
  * mdadm - manage Linux "md" devices aka RAID arrays.
  *
- * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
+ * Copyright (C) 2001-2006 Neil Brown <neilb@suse.de>
  *
  *
  *    This program is free software; you can redistribute it and/or modify
@@ -31,193 +31,369 @@
 #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 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, minor;
+	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;
-	char *name = malloc(strlen(dev) + 20);
+	int nlen = strlen(dev) + 20;
+	char *name = malloc(nlen);
 	int dig = isdigit(dev[strlen(dev)-1]);
+	char orig[1024];
+	char sym[1024];
+	int err;
 
-	if (stat(dev, &stb)!= 0)
-		return;
-	if (!S_ISBLK(stb.st_mode))
+	if (cnt==0) cnt=4;
+	if (lstat(dev, &stb)!= 0)
 		return;
-	major = major(stb.st_rdev);
-	minor = minor(stb.st_rdev);
+	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;
-		sprintf(name, "%s%s%d", dev, dig?"p":"", i);
+		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))
+			if (stb2.st_rdev == makedev(major_num, minor_num+i))
 				continue;
 			unlink(name);
 		} else {
 			stb2 = stb;
 		}
-		mknod(name, S_IFBLK | 0600, makedev(major, minor+i));
-		chown(name, stb2.st_uid, stb2.st_gid);
-		chmod(name, stb2.st_mode & 07777);
+		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);
 	}
 }
 
+
 /*
- * 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 is user=0, group=0 perm=0600
+ * 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 open_mddev(char *dev, int autof)
+
+int create_mddev(char *dev, char *name, int autof, int trustworthy,
+		 char *chosen)
 {
 	int mdfd;
 	struct stat stb;
-	int major = MD_MAJOR;
-	int minor = 0;
-	int must_remove = 0;
-	struct mdstat_ent *mdlist;
-	int num;
-
-	if (autof) {
-		/* autof is set, so we need to check that the name is ok,
-		 * and possibly create one if not
+	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 (autof == -2 && !is_standard(dev, NULL)) {
-			fprintf(stderr, Name ": --auto=yes requires a 'standard' md device name, not %s\n", dev);
+		if (strchr(cname, '/') != NULL) {
+			fprintf(stderr, Name ": %s is an invalid name "
+				"for an md device.\n", dev);
 			return -1;
 		}
-		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);
+		if (cname[0] == 0) {
+			fprintf(stderr, Name ": %s is an invalid name "
+				"for an md device (empty!).", dev);
 			return -1;
 		}
-		/* check major number is correct */
-		if (autof>0)
-			major = get_mdp_major();
-		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 */
-				must_remove = 1;
-				close(mdfd);
-			} else {
-				if (autof > 0)
-					make_parts(dev, autof);
-				return mdfd;
-			}
+		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, use that for num
+		 * if it is not already in use */
+		char *ep;
+		num = strtoul(name, &ep, 10);
+		if (ep == name || *ep)
+			num = -1;
+		else if (mddev_busy(use_mdp ? (-1-num) : num))
+			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;
 		}
-		/* 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)
+		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 '/'
 		 */
-		switch(is_standard(dev, &num)) {
-		case -1: /* non partitioned */
-			if (autof > 0) {
-				fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
+		char *cp;
+		struct map_ent *map = NULL;
+		int conflict = 1;
+		int unum = 0;
+		int cnlen;
+		strncpy(cname, name, 200);
+		cname[200] = 0;
+		while ((cp = strchr(cname, '/')) != NULL)
+			*cp = '-';
+		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)
+				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;
+		}
+	}
+	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;
 			}
-			minor = num;
-			num = -1-num;
-			break;
-		case 1: /* partitioned */
-			if (autof == -1) {
-				fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
+		} else {
+			if (mknod(devname, S_IFBLK|0600,
+				  makedev(dev2major(num),dev2minor(num))) != 0) {
+				fprintf(stderr, Name ": failed to create %s\n",
+					devname);
 				return -1;
 			}
-			minor = num <<  MdpMinorShift;
-			major = get_mdp_major();
-			break;
-		case 0: /* not standard, pick an unused number */
-			mdlist = mdstat_read(0);
-			for (num= (autof>0)?-1:0 ; ; num+= (autof>2)?-1:1) {
-				struct mdstat_ent *me;
-				for (me=mdlist; me; me=me->next)
-					if (me->devnum == num)
-						break;
-				if (!me) {
-					/* doesn't exist if mdstat.
-					 * make sure it is new to /dev too
-					 */
-					char *dn;
-					if (autof > 0) 
-						minor = (-1-num) << MdpMinorShift;
-					else
-						minor = num;
-					dn = map_dev(major,minor);
-					if (dn==NULL || is_standard(dn, NULL)) {
-						/* this number only used by a 'standard' name,
-						 * so it is safe to use
-						 */
-						break;
-					}
-				}
-			}
+			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);
 		}
-		/* 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 (use_mdp == 1)
+			make_parts(devname, parts);
+		if (strcmp(chosen, devname) != 0) {
 
-			if (mknod(dev, S_IFBLK|0600, makedev(major, minor))!= 0) {
-				fprintf(stderr, Name ": failed to create %s\n", dev);
-				return -1;
+			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 (must_remove) {
-				chown(dev, stb.st_uid, stb.st_gid);
-				chmod(dev, stb.st_mode & 07777);
-			}
-			make_parts(dev,autof);
+
+			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 if (symlink(devname, chosen) != 0)
+				fprintf(stderr, Name ": failed to create %s: %s\n",
+					chosen, strerror(errno));
+			if (use_mdp && strcmp(chosen, devname) != 0)
+				make_parts(chosen, parts);
 		}
 	}
-	mdfd = open(dev, O_RDWR, 0);
+	mdfd = open_dev_excl(num);
 	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);
+		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);
-		mdfd = -1;
+		if (report_errors)
+			fprintf(stderr, Name ": %s does not appear to be "
+				"an md device\n", dev);
+		return -2;
 	}
 	return mdfd;
 }
-