mdadm (3.3.2-5) unstable; urgency=medium

  * use-tempnode-not-devnode.patch: change udev rules file to use
    $tempnode which works both on wheezy and jessie udev, instead
    of $devnode which only works in jessie.  At this stage it is
    better to make rules file compatible with old version instead
    of adding versioned dependency.  Should be removed for jessie+1.
    (Closes: #770883)
  * fix Closes: list in previous entry (Closes: #771852)

# imported from the archive

1 files changed, 921 insertions, 0 deletions

diff --git a/sysfs.c b/sysfs.c
new file mode 100644
index 00000000..9a1d8569
--- /dev/null
+++ b/sysfs.c
@@ -0,0 +1,921 @@
+/*
+ * sysfs - extract md related information from sysfs.  Part of:
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2006-2009 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	<dirent.h>
+#include	<ctype.h>
+
+int load_sys(char *path, char *buf)
+{
+	int fd = open(path, O_RDONLY);
+	int n;
+	if (fd < 0)
+		return -1;
+	n = read(fd, buf, 1024);
+	close(fd);
+	if (n <0 || n >= 1024)
+		return -1;
+	buf[n] = 0;
+	if (n && buf[n-1] == '\n')
+		buf[n-1] = 0;
+	return 0;
+}
+
+void sysfs_free(struct mdinfo *sra)
+{
+	while (sra) {
+		struct mdinfo *sra2 = sra->next;
+		while (sra->devs) {
+			struct mdinfo *d = sra->devs;
+			sra->devs = d->next;
+			free(d);
+		}
+		free(sra);
+		sra = sra2;
+	}
+}
+
+int sysfs_open(char *devnm, char *devname, char *attr)
+{
+	char fname[50];
+	int fd;
+
+	sprintf(fname, "/sys/block/%s/md/", devnm);
+	if (devname) {
+		strcat(fname, devname);
+		strcat(fname, "/");
+	}
+	strcat(fname, attr);
+	fd = open(fname, O_RDWR);
+	if (fd < 0 && errno == EACCES)
+		fd = open(fname, O_RDONLY);
+	return fd;
+}
+
+void sysfs_init(struct mdinfo *mdi, int fd, char *devnm)
+{
+	mdi->sys_name[0] = 0;
+	if (fd >= 0) {
+		mdu_version_t vers;
+		if (ioctl(fd, RAID_VERSION, &vers) != 0)
+			return;
+		devnm = fd2devnm(fd);
+	}
+	if (devnm == NULL)
+		return;
+	strcpy(mdi->sys_name, devnm);
+}
+
+struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options)
+{
+	char fname[PATH_MAX];
+	char buf[PATH_MAX];
+	char *base;
+	char *dbase;
+	struct mdinfo *sra;
+	struct mdinfo *dev, **devp;
+	DIR *dir = NULL;
+	struct dirent *de;
+
+	sra = xcalloc(1, sizeof(*sra));
+	sysfs_init(sra, fd, devnm);
+	if (sra->sys_name[0] == 0) {
+		free(sra);
+		return NULL;
+	}
+
+	sprintf(fname, "/sys/block/%s/md/", sra->sys_name);
+	base = fname + strlen(fname);
+
+	sra->devs = NULL;
+	if (options & GET_VERSION) {
+		strcpy(base, "metadata_version");
+		if (load_sys(fname, buf))
+			goto abort;
+		if (strncmp(buf, "none", 4) == 0) {
+			sra->array.major_version =
+				sra->array.minor_version = -1;
+			strcpy(sra->text_version, "");
+		} else if (strncmp(buf, "external:", 9) == 0) {
+			sra->array.major_version = -1;
+			sra->array.minor_version = -2;
+			strcpy(sra->text_version, buf+9);
+		} else {
+			sscanf(buf, "%d.%d",
+			       &sra->array.major_version,
+			       &sra->array.minor_version);
+			strcpy(sra->text_version, buf);
+		}
+	}
+	if (options & GET_LEVEL) {
+		strcpy(base, "level");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->array.level = map_name(pers, buf);
+	}
+	if (options & GET_LAYOUT) {
+		strcpy(base, "layout");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->array.layout = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_DISKS) {
+		strcpy(base, "raid_disks");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->array.raid_disks = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_DEGRADED) {
+		strcpy(base, "degraded");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->array.failed_disks = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_COMPONENT) {
+		strcpy(base, "component_size");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->component_size = strtoull(buf, NULL, 0);
+		/* sysfs reports "K", but we want sectors */
+		sra->component_size *= 2;
+	}
+	if (options & GET_CHUNK) {
+		strcpy(base, "chunk_size");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->array.chunk_size = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_CACHE) {
+		strcpy(base, "stripe_cache_size");
+		if (load_sys(fname, buf))
+			/* Probably level doesn't support it */
+			sra->cache_size = 0;
+		else
+			sra->cache_size = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_MISMATCH) {
+		strcpy(base, "mismatch_cnt");
+		if (load_sys(fname, buf))
+			goto abort;
+		sra->mismatch_cnt = strtoul(buf, NULL, 0);
+	}
+	if (options & GET_SAFEMODE) {
+		int scale = 1;
+		int dot = 0;
+		unsigned i;
+		unsigned long msec;
+		size_t len;
+
+		strcpy(base, "safe_mode_delay");
+		if (load_sys(fname, buf))
+			goto abort;
+
+		/* remove a period, and count digits after it */
+		len = strlen(buf);
+		for (i = 0; i < len; i++) {
+			if (dot) {
+				if (isdigit(buf[i])) {
+					buf[i-1] = buf[i];
+					scale *= 10;
+				}
+				buf[i] = 0;
+			} else if (buf[i] == '.') {
+				dot=1;
+				buf[i] = 0;
+			}
+		}
+		msec = strtoul(buf, NULL, 10);
+		msec = (msec * 1000) / scale;
+		sra->safe_mode_delay = msec;
+	}
+	if (options & GET_BITMAP_LOCATION) {
+		strcpy(base, "bitmap/location");
+		if (load_sys(fname, buf))
+			goto abort;
+		if (strncmp(buf, "file", 4) == 0)
+			sra->bitmap_offset = 1;
+		else if (strncmp(buf, "none", 4) == 0)
+			sra->bitmap_offset = 0;
+		else if (buf[0] == '+')
+			sra->bitmap_offset = strtol(buf+1, NULL, 10);
+		else
+			goto abort;
+	}
+
+	if (! (options & GET_DEVS))
+		return sra;
+
+	/* Get all the devices as well */
+	*base = 0;
+	dir = opendir(fname);
+	if (!dir)
+		goto abort;
+	sra->array.spare_disks = 0;
+
+	devp = &sra->devs;
+	sra->devs = NULL;
+	while ((de = readdir(dir)) != NULL) {
+		char *ep;
+		if (de->d_ino == 0 ||
+		    strncmp(de->d_name, "dev-", 4) != 0)
+			continue;
+		strcpy(base, de->d_name);
+		dbase = base + strlen(base);
+		*dbase++ = '/';
+
+		dev = xmalloc(sizeof(*dev));
+
+		/* Always get slot, major, minor */
+		strcpy(dbase, "slot");
+		if (load_sys(fname, buf)) {
+			/* hmm... unable to read 'slot' maybe the device
+			 * is going away?
+			 */
+			strcpy(dbase, "block");
+			if (readlink(fname, buf, sizeof(buf)) < 0 &&
+			    errno != ENAMETOOLONG) {
+				/* ...yup device is gone */
+				free(dev);
+				continue;
+			} else {
+				/* slot is unreadable but 'block' link
+				 * still intact... something bad is happening
+				 * so abort
+				 */
+				free(dev);
+				goto abort;
+			}
+
+		}
+		strcpy(dev->sys_name, de->d_name);
+		dev->disk.raid_disk = strtoul(buf, &ep, 10);
+		if (*ep) dev->disk.raid_disk = -1;
+
+		strcpy(dbase, "block/dev");
+		if (load_sys(fname, buf)) {
+			/* assume this is a stale reference to a hot
+			 * removed device
+			 */
+			free(dev);
+			continue;
+		}
+		sra->array.nr_disks++;
+		sscanf(buf, "%d:%d", &dev->disk.major, &dev->disk.minor);
+
+		/* special case check for block devices that can go 'offline' */
+		strcpy(dbase, "block/device/state");
+		if (load_sys(fname, buf) == 0 &&
+		    strncmp(buf, "offline", 7) == 0) {
+			free(dev);
+			continue;
+		}
+
+		/* finally add this disk to the array */
+		*devp = dev;
+		devp = & dev->next;
+		dev->next = NULL;
+
+		if (options & GET_OFFSET) {
+			strcpy(dbase, "offset");
+			if (load_sys(fname, buf))
+				goto abort;
+			dev->data_offset = strtoull(buf, NULL, 0);
+			strcpy(dbase, "new_offset");
+			if (load_sys(fname, buf) == 0)
+				dev->new_data_offset = strtoull(buf, NULL, 0);
+			else
+				dev->new_data_offset = dev->data_offset;
+		}
+		if (options & GET_SIZE) {
+			strcpy(dbase, "size");
+			if (load_sys(fname, buf))
+				goto abort;
+			dev->component_size = strtoull(buf, NULL, 0) * 2;
+		}
+		if (options & GET_STATE) {
+			dev->disk.state = 0;
+			strcpy(dbase, "state");
+			if (load_sys(fname, buf))
+				goto abort;
+			if (strstr(buf, "in_sync"))
+				dev->disk.state |= (1<<MD_DISK_SYNC);
+			if (strstr(buf, "faulty"))
+				dev->disk.state |= (1<<MD_DISK_FAULTY);
+			if (dev->disk.state == 0)
+				sra->array.spare_disks++;
+		}
+		if (options & GET_ERROR) {
+			strcpy(buf, "errors");
+			if (load_sys(fname, buf))
+				goto abort;
+			dev->errors = strtoul(buf, NULL, 0);
+		}
+	}
+	closedir(dir);
+	return sra;
+
+ abort:
+	if (dir)
+		closedir(dir);
+	sysfs_free(sra);
+	return NULL;
+}
+
+int sysfs_attr_match(const char *attr, const char *str)
+{
+	/* See if attr, read from a sysfs file, matches
+	 * str.  They must either be the same, or attr can
+	 * have a trailing newline or comma
+	 */
+	while (*attr && *str && *attr == *str) {
+		attr++;
+		str++;
+	}
+
+	if (*str || (*attr && *attr != ',' && *attr != '\n'))
+		return 0;
+	return 1;
+}
+
+int sysfs_match_word(const char *word, char **list)
+{
+	int n;
+	for (n=0; list[n]; n++)
+		if (sysfs_attr_match(word, list[n]))
+			break;
+	return n;
+}
+
+unsigned long long get_component_size(int fd)
+{
+	/* Find out the component size of the array.
+	 * We cannot trust GET_ARRAY_INFO ioctl as it's
+	 * size field is only 32bits.
+	 * So look in /sys/block/mdXXX/md/component_size
+	 *
+	 * This returns in units of sectors.
+	 */
+	struct stat stb;
+	char fname[50];
+	int n;
+	if (fstat(fd, &stb)) return 0;
+	if (major(stb.st_rdev) != (unsigned)get_mdp_major())
+		sprintf(fname, "/sys/block/md%d/md/component_size",
+			(int)minor(stb.st_rdev));
+	else
+		sprintf(fname, "/sys/block/md_d%d/md/component_size",
+			(int)minor(stb.st_rdev)>>MdpMinorShift);
+	fd = open(fname, O_RDONLY);
+	if (fd < 0)
+		return 0;
+	n = read(fd, fname, sizeof(fname));
+	close(fd);
+	if (n < 0 || n == sizeof(fname))
+		return 0;
+	fname[n] = 0;
+	return strtoull(fname, NULL, 10) * 2;
+}
+
+int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
+		  char *name, char *val)
+{
+	char fname[50];
+	unsigned int n;
+	int fd;
+
+	sprintf(fname, "/sys/block/%s/md/%s/%s",
+		sra->sys_name, dev?dev->sys_name:"", name);
+	fd = open(fname, O_WRONLY);
+	if (fd < 0)
+		return -1;
+	n = write(fd, val, strlen(val));
+	close(fd);
+	if (n != strlen(val)) {
+		dprintf(Name ": failed to write '%s' to '%s' (%s)\n",
+			val, fname, strerror(errno));
+		return -1;
+	}
+	return 0;
+}
+
+int sysfs_set_num(struct mdinfo *sra, struct mdinfo *dev,
+		  char *name, unsigned long long val)
+{
+	char valstr[50];
+	sprintf(valstr, "%llu", val);
+	return sysfs_set_str(sra, dev, name, valstr);
+}
+
+int sysfs_set_num_signed(struct mdinfo *sra, struct mdinfo *dev,
+			 char *name, long long val)
+{
+	char valstr[50];
+	sprintf(valstr, "%lli", val);
+	return sysfs_set_str(sra, dev, name, valstr);
+}
+
+int sysfs_uevent(struct mdinfo *sra, char *event)
+{
+	char fname[50];
+	int n;
+	int fd;
+
+	sprintf(fname, "/sys/block/%s/uevent",
+		sra->sys_name);
+	fd = open(fname, O_WRONLY);
+	if (fd < 0)
+		return -1;
+	n = write(fd, event, strlen(event));
+	close(fd);
+	if (n != (int)strlen(event)) {
+		dprintf(Name ": failed to write '%s' to '%s' (%s)\n",
+			event, fname, strerror(errno));
+		return -1;
+	}
+	return 0;
+}
+
+int sysfs_attribute_available(struct mdinfo *sra, struct mdinfo *dev, char *name)
+{
+	char fname[50];
+	struct stat st;
+
+	sprintf(fname, "/sys/block/%s/md/%s/%s",
+		sra->sys_name, dev?dev->sys_name:"", name);
+
+	return stat(fname, &st) == 0;
+}
+
+int sysfs_get_fd(struct mdinfo *sra, struct mdinfo *dev,
+		       char *name)
+{
+	char fname[50];
+	int fd;
+
+	sprintf(fname, "/sys/block/%s/md/%s/%s",
+		sra->sys_name, dev?dev->sys_name:"", name);
+	fd = open(fname, O_RDWR);
+	if (fd < 0)
+		fd = open(fname, O_RDONLY);
+	return fd;
+}
+
+int sysfs_fd_get_ll(int fd, unsigned long long *val)
+{
+	char buf[50];
+	int n;
+	char *ep;
+
+	lseek(fd, 0, 0);
+	n = read(fd, buf, sizeof(buf));
+	if (n <= 0)
+		return -2;
+	buf[n] = 0;
+	*val = strtoull(buf, &ep, 0);
+	if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
+		return -1;
+	return 0;
+}
+
+int sysfs_get_ll(struct mdinfo *sra, struct mdinfo *dev,
+		       char *name, unsigned long long *val)
+{
+	int n;
+	int fd;
+
+	fd = sysfs_get_fd(sra, dev, name);
+	if (fd < 0)
+		return -1;
+	n = sysfs_fd_get_ll(fd, val);
+	close(fd);
+	return n;
+}
+
+int sysfs_fd_get_two(int fd, unsigned long long *v1, unsigned long long *v2)
+{
+	/* two numbers in this sysfs file, either
+	 *  NNN (NNN)
+	 * or
+	 *  NNN / NNN
+	 */
+	char buf[80];
+	int n;
+	char *ep, *ep2;
+
+	lseek(fd, 0, 0);
+	n = read(fd, buf, sizeof(buf));
+	if (n <= 0)
+		return -2;
+	buf[n] = 0;
+	*v1 = strtoull(buf, &ep, 0);
+	if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
+		return -1;
+	while (*ep == ' ' || *ep == '/' || *ep == '(')
+		ep++;
+	*v2 = strtoull(ep, &ep2, 0);
+	if (ep2 == ep || (*ep2 != 0 && *ep2 != '\n' && *ep2 != ' ' && *ep2 != ')')) {
+		*v2 = *v1;
+		return 1;
+	}
+	return 2;
+}
+
+int sysfs_get_two(struct mdinfo *sra, struct mdinfo *dev,
+		  char *name, unsigned long long *v1, unsigned long long *v2)
+{
+	int n;
+	int fd;
+
+	fd = sysfs_get_fd(sra, dev, name);
+	if (fd < 0)
+		return -1;
+	n = sysfs_fd_get_two(fd, v1, v2);
+	close(fd);
+	return n;
+}
+
+int sysfs_fd_get_str(int fd, char *val, int size)
+{
+	int n;
+
+	lseek(fd, 0, 0);
+	n = read(fd, val, size);
+	if (n <= 0)
+		return -1;
+	val[n] = 0;
+	return n;
+}
+
+int sysfs_get_str(struct mdinfo *sra, struct mdinfo *dev,
+		       char *name, char *val, int size)
+{
+	int n;
+	int fd;
+
+	fd = sysfs_get_fd(sra, dev, name);
+	if (fd < 0)
+		return -1;
+	n = sysfs_fd_get_str(fd, val, size);
+	close(fd);
+	return n;
+}
+
+int sysfs_set_safemode(struct mdinfo *sra, unsigned long ms)
+{
+	unsigned long sec;
+	unsigned long msec;
+	char delay[30];
+
+	sec = ms / 1000;
+	msec = ms % 1000;
+
+	sprintf(delay, "%ld.%03ld\n", sec, msec);
+	/*             this '\n' ^ needed for kernels older than 2.6.28 */
+	return sysfs_set_str(sra, NULL, "safe_mode_delay", delay);
+}
+
+int sysfs_set_array(struct mdinfo *info, int vers)
+{
+	int rv = 0;
+	char ver[100];
+	int raid_disks = info->array.raid_disks;
+
+	ver[0] = 0;
+	if (info->array.major_version == -1 &&
+	    info->array.minor_version == -2) {
+		char buf[1024];
+
+		strcat(strcpy(ver, "external:"), info->text_version);
+
+		/* meta version might already be set if we are setting
+		 * new geometry for a reshape.  In that case we don't
+		 * want to over-write the 'readonly' flag that is
+		 * stored in the metadata version.  So read the current
+		 * version first, and preserve the flag
+		 */
+		if (sysfs_get_str(info, NULL, "metadata_version",
+				  buf, 1024) > 0)
+			if (strlen(buf) >= 9 && buf[9] == '-')
+				ver[9] = '-';
+
+		if ((vers % 100) < 2 ||
+		    sysfs_set_str(info, NULL, "metadata_version",
+				  ver) < 0) {
+			pr_err("This kernel does not "
+				"support external metadata.\n");
+			return 1;
+		}
+	}
+	if (info->array.level < 0)
+		return 0; /* FIXME */
+	rv |= sysfs_set_str(info, NULL, "level",
+			    map_num(pers, info->array.level));
+	if (info->reshape_active && info->delta_disks != UnSet)
+		raid_disks -= info->delta_disks;
+	rv |= sysfs_set_num(info, NULL, "raid_disks", raid_disks);
+	rv |= sysfs_set_num(info, NULL, "chunk_size", info->array.chunk_size);
+	rv |= sysfs_set_num(info, NULL, "layout", info->array.layout);
+	rv |= sysfs_set_num(info, NULL, "component_size", info->component_size/2);
+	if (info->custom_array_size) {
+		int rc;
+
+		rc = sysfs_set_num(info, NULL, "array_size",
+				   info->custom_array_size/2);
+		if (rc && errno == ENOENT) {
+			pr_err("This kernel does not "
+				"have the md/array_size attribute, "
+				"the array may be larger than expected\n");
+			rc = 0;
+		}
+		rv |= rc;
+	}
+
+	if (info->array.level > 0)
+		rv |= sysfs_set_num(info, NULL, "resync_start", info->resync_start);
+
+	if (info->reshape_active) {
+		rv |= sysfs_set_num(info, NULL, "reshape_position",
+				    info->reshape_progress);
+		rv |= sysfs_set_num(info, NULL, "chunk_size", info->new_chunk);
+		rv |= sysfs_set_num(info, NULL, "layout", info->new_layout);
+		rv |= sysfs_set_num(info, NULL, "raid_disks",
+				    info->array.raid_disks);
+		/* We don't set 'new_level' here.  That can only happen
+		 * once the reshape completes.
+		 */
+	}
+	return rv;
+}
+
+int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume)
+{
+	char dv[PATH_MAX];
+	char nm[PATH_MAX];
+	char *dname;
+	int rv;
+
+	sprintf(dv, "%d:%d", sd->disk.major, sd->disk.minor);
+	rv = sysfs_set_str(sra, NULL, "new_dev", dv);
+	if (rv)
+		return rv;
+
+	memset(nm, 0, sizeof(nm));
+	dname = devid2kname(makedev(sd->disk.major, sd->disk.minor));
+	strcpy(sd->sys_name, "dev-");
+	strcpy(sd->sys_name+4, dname);
+
+	/* test write to see if 'recovery_start' is available */
+	if (resume && sd->recovery_start < MaxSector &&
+	    sysfs_set_num(sra, sd, "recovery_start", 0)) {
+		sysfs_set_str(sra, sd, "state", "remove");
+		return -1;
+	}
+
+	rv = sysfs_set_num(sra, sd, "offset", sd->data_offset);
+	rv |= sysfs_set_num(sra, sd, "size", (sd->component_size+1) / 2);
+	if (sra->array.level != LEVEL_CONTAINER) {
+		if (sd->recovery_start == MaxSector)
+			/* This can correctly fail if array isn't started,
+			 * yet, so just ignore status for now.
+			 */
+			sysfs_set_str(sra, sd, "state", "insync");
+		if (sd->disk.raid_disk >= 0)
+			rv |= sysfs_set_num(sra, sd, "slot", sd->disk.raid_disk);
+		if (resume)
+			sysfs_set_num(sra, sd, "recovery_start", sd->recovery_start);
+	}
+	return rv;
+}
+
+#if 0
+int sysfs_disk_to_sg(int fd)
+{
+	/* from an open block device, try find and open its corresponding
+	 * scsi_generic interface
+	 */
+	struct stat st;
+	char path[256];
+	char sg_path[256];
+	char sg_major_minor[8];
+	char *c;
+	DIR *dir;
+	struct dirent *de;
+	int major, minor, rv;
+
+	if (fstat(fd, &st))
+		return -1;
+
+	snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device",
+		 major(st.st_rdev), minor(st.st_rdev));
+
+	dir = opendir(path);
+	if (!dir)
+		return -1;
+
+	de = readdir(dir);
+	while (de) {
+		if (strncmp("scsi_generic:", de->d_name,
+			    strlen("scsi_generic:")) == 0)
+			break;
+		de = readdir(dir);
+	}
+	closedir(dir);
+
+	if (!de)
+		return -1;
+
+	snprintf(sg_path, sizeof(sg_path), "%s/%s/dev", path, de->d_name);
+	fd = open(sg_path, O_RDONLY);
+	if (fd < 0)
+		return fd;
+
+	rv = read(fd, sg_major_minor, sizeof(sg_major_minor));
+	close(fd);
+	if (rv < 0)
+		return -1;
+	else
+		sg_major_minor[rv - 1] = '\0';
+
+	c = strchr(sg_major_minor, ':');
+	*c = '\0';
+	c++;
+	major = strtol(sg_major_minor, NULL, 10);
+	minor = strtol(c, NULL, 10);
+	snprintf(path, sizeof(path), "/dev/.tmp.md.%d:%d:%d",
+		 (int) getpid(), major, minor);
+	if (mknod(path, S_IFCHR|0600, makedev(major, minor))==0) {
+			fd = open(path, O_RDONLY);
+			unlink(path);
+			return fd;
+	}
+
+	return -1;
+}
+#endif
+
+int sysfs_disk_to_scsi_id(int fd, __u32 *id)
+{
+	/* from an open block device, try to retrieve it scsi_id */
+	struct stat st;
+	char path[256];
+	DIR *dir;
+	struct dirent *de;
+	int host, bus, target, lun;
+
+	if (fstat(fd, &st))
+		return 1;
+
+	snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device/scsi_device",
+		 major(st.st_rdev), minor(st.st_rdev));
+
+	dir = opendir(path);
+	if (!dir)
+		return 1;
+
+	for (de = readdir(dir); de; de = readdir(dir)) {
+		int count;
+
+		if (de->d_type != DT_DIR)
+			continue;
+
+		count = sscanf(de->d_name, "%d:%d:%d:%d", &host, &bus, &target, &lun);
+		if (count == 4)
+			break;
+	}
+	closedir(dir);
+
+	if (!de)
+		return 1;
+
+	*id = (host << 24) | (bus << 16) | (target << 8) | (lun << 0);
+	return 0;
+}
+
+int sysfs_unique_holder(char *devnm, long rdev)
+{
+	/* Check that devnm is a holder of rdev,
+	 * and is the only holder.
+	 * we should be locked against races by
+	 * an O_EXCL on devnm
+	 * Return values:
+	 *  0 - not unique, not even a holder
+	 *  1 - unique, this is the only holder.
+	 *  2/3 - not unique, there is another holder
+	 * -1 - error, cannot find the holders
+	 */
+	DIR *dir;
+	struct dirent *de;
+	char dirname[100];
+	char l;
+	int ret = 0;
+	sprintf(dirname, "/sys/dev/block/%d:%d/holders",
+		major(rdev), minor(rdev));
+	dir = opendir(dirname);
+	if (!dir)
+		return -1;
+	l = strlen(dirname);
+	while ((de = readdir(dir)) != NULL) {
+		char buf[100];
+		char *sl;
+		int n;
+
+		if (de->d_ino == 0)
+			continue;
+		if (de->d_name[0] == '.')
+			continue;
+		strcpy(dirname+l, "/");
+		strcat(dirname+l, de->d_name);
+		n = readlink(dirname, buf, sizeof(buf)-1);
+		if (n <= 0)
+			continue;
+		buf[n] = 0;
+		sl = strrchr(buf, '/');
+		if (!sl)
+			continue;
+		sl++;
+
+		if (strcmp(devnm, sl) == 0)
+			ret |= 1;
+		else
+			ret |= 2;
+	}
+	closedir(dir);
+	return ret;
+}
+
+int sysfs_freeze_array(struct mdinfo *sra)
+{
+	/* Try to freeze resync/rebuild on this array/container.
+	 * Return -1 if the array is busy,
+	 * return 0 if this kernel doesn't support 'frozen'
+	 * return 1 if it worked.
+	 */
+	char buf[20];
+
+	if (!sysfs_attribute_available(sra, NULL, "sync_action"))
+		return 1; /* no sync_action == frozen */
+	if (sysfs_get_str(sra, NULL, "sync_action", buf, 20) <= 0)
+		return 0;
+	if (strcmp(buf, "frozen\n") == 0)
+		/* Already frozen */
+		return 0;
+	if (strcmp(buf, "idle\n") != 0 && strcmp(buf, "recover\n") != 0)
+		return -1;
+	if (sysfs_set_str(sra, NULL, "sync_action", "frozen") < 0)
+		return 0;
+	return 1;
+}
+
+int sysfs_wait(int fd, int *msec)
+{
+	/* Wait up to '*msec' for fd to have an exception condition.
+	 * if msec == NULL, wait indefinitely.
+	 */
+	fd_set fds;
+	int n;
+	FD_ZERO(&fds);
+	FD_SET(fd, &fds);
+	if (msec == NULL)
+		n = select(fd+1, NULL, NULL, &fds, NULL);
+	else if (*msec < 0)
+		n = 0;
+	else {
+		struct timeval start, end, tv;
+		gettimeofday(&start, NULL);
+		if (*msec < 1000) {
+			tv.tv_sec = 0;
+			tv.tv_usec = (*msec)*1000;
+		} else {
+			tv.tv_sec = (*msec)/1000;
+			tv.tv_usec = 0;
+		}
+		n = select(fd+1, NULL, NULL, &fds, &tv);
+		gettimeofday(&end, NULL);
+		end.tv_sec -= start.tv_sec;
+		*msec -= (end.tv_sec * 1000 + end.tv_usec/1000
+			  - start.tv_usec/1000) + 1;
+	}
+	return n;
+}