Adding upstream version 4.2.upstream/4.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 509 insertions, 0 deletions

diff --git a/mdopen.c b/mdopen.c
new file mode 100644
index 0000000..245be53
--- /dev/null
+++ b/mdopen.c
@@ -0,0 +1,509 @@
+/*
+ * 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 to create %s when using %s, fallback to creation via node\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;
+}