Manage: Block unsafe member failing

[thirdparty/mdadm.git] / Manage.c

/*
 * 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_u.h"
#include "md_p.h"
#include <ctype.h>

int Manage_ro(char *devname, int fd, int readonly)
{
        /* switch to readonly or rw
         *
         * requires >= 0.90.0
         * first check that array is runing
         * use RESTART_ARRAY_RW or STOP_ARRAY_RO
         *
         */
        struct mdinfo *mdi;
        int rv = 0;

        /* If this is an externally-managed array, we need to modify the
         * metadata_version so that mdmon doesn't undo our change.
         */
        mdi = sysfs_read(fd, NULL, GET_LEVEL|GET_VERSION);
        if (mdi &&
            mdi->array.major_version == -1 &&
            is_subarray(mdi->text_version)) {
                char vers[64];
                strcpy(vers, "external:");
                strcat(vers, mdi->text_version);
                if (readonly > 0) {
                        int rv;
                        /* We set readonly ourselves. */
                        vers[9] = '-';
                        sysfs_set_str(mdi, NULL, "metadata_version", vers);

                        close(fd);
                        rv = sysfs_set_str(mdi, NULL, "array_state", "readonly");

                        if (rv < 0) {
                                pr_err("failed to set readonly for %s: %s\n",
                                        devname, strerror(errno));

                                vers[9] = mdi->text_version[0];
                                sysfs_set_str(mdi, NULL, "metadata_version", vers);
                                rv = 1;
                                goto out;
                        }
                } else {
                        char *cp;
                        /* We cannot set read/write - must signal mdmon */
                        vers[9] = '/';
                        sysfs_set_str(mdi, NULL, "metadata_version", vers);

                        cp = strchr(vers+10, '/');
                        if (cp)
                                *cp = 0;
                        ping_monitor(vers+10);
                        if (mdi->array.level <= 0)
                                sysfs_set_str(mdi, NULL, "array_state", "active");
                }
                goto out;
        }

        if (!md_array_active(fd)) {
                pr_err("%s does not appear to be active.\n", devname);
                rv = 1;
                goto out;
        }

        if (readonly > 0) {
                if (ioctl(fd, STOP_ARRAY_RO, NULL)) {
                        pr_err("failed to set readonly for %s: %s\n",
                                devname, strerror(errno));
                        rv = 1;
                        goto out;
                }
        } else if (readonly < 0) {
                if (ioctl(fd, RESTART_ARRAY_RW, NULL)) {
                        pr_err("failed to set writable for %s: %s\n",
                                devname, strerror(errno));
                        rv = 1;
                        goto out;
                }
        }
out:
        sysfs_free(mdi);
        return rv;
}

static void remove_devices(char *devnm, char *path)
{
        /*
         * Remove names at 'path' - possibly with
         * partition suffixes - which link to the 'standard'
         * name for devnm.  These were probably created
         * by mdadm when the array was assembled.
         */
        char base[40];
        char *path2;
        char link[1024];
        int n;
        int part;
        char *be;
        char *pe;

        if (!path)
                return;

        sprintf(base, "/dev/%s", devnm);
        be = base + strlen(base);

        path2 = xmalloc(strlen(path)+20);
        strcpy(path2, path);
        pe = path2 + strlen(path2);

        for (part = 0; part < 16; part++) {
                if (part) {
                        sprintf(be, "p%d", part);

                        if (isdigit(pe[-1]))
                                sprintf(pe, "p%d", part);
                        else
                                sprintf(pe, "%d", part);
                }
                n = readlink(path2, link, sizeof(link));
                if (n > 0 && (int)strlen(base) == n &&
                    strncmp(link, base, n) == 0)
                        unlink(path2);
        }
        free(path2);
}

int Manage_run(char *devname, int fd, struct context *c)
{
        /* Run the array.  Array must already be configured
         *  Requires >= 0.90.0
         */
        char nm[32], *nmp;

        nmp = fd2devnm(fd);
        if (!nmp) {
                pr_err("Cannot find %s in sysfs!!\n", devname);
                return 1;
        }
        strcpy(nm, nmp);
        return IncrementalScan(c, nm);
}

int Manage_stop(char *devname, int fd, int verbose, int will_retry)
{
        /* Stop the array.  Array must already be configured
         * 'will_retry' means that error messages are not wanted.
         */
        int rv = 0;
        struct map_ent *map = NULL;
        struct mdinfo *mdi;
        char devnm[32];
        char container[32];
        int err;
        int count;
        char buf[32];
        unsigned long long rd1, rd2;

        if (will_retry && verbose == 0)
                verbose = -1;

        strcpy(devnm, fd2devnm(fd));
        /* Get EXCL access first.  If this fails, then attempting
         * to stop is probably a bad idea.
         */
        mdi = sysfs_read(fd, NULL, GET_LEVEL|GET_COMPONENT|GET_VERSION);
        if (mdi && is_subarray(mdi->text_version)) {
                char *sl;
                strncpy(container, mdi->text_version+1, sizeof(container));
                container[sizeof(container)-1] = 0;
                sl = strchr(container, '/');
                if (sl)
                        *sl = 0;
        } else
                container[0] = 0;
        close(fd);
        count = 5;
        while (((fd = ((devname[0] == '/')
                       ?open(devname, O_RDONLY|O_EXCL)
                       :open_dev_flags(devnm, O_RDONLY|O_EXCL))) < 0 ||
                strcmp(fd2devnm(fd), devnm) != 0) && container[0] &&
               mdmon_running(container) && count) {
                /* Can't open, so something might be wrong.  However it
                 * is a container, so we might be racing with mdmon, so
                 * retry for a bit.
                 */
                if (fd >= 0)
                        close(fd);
                flush_mdmon(container);
                count--;
        }
        if (fd < 0 || strcmp(fd2devnm(fd), devnm) != 0) {
                if (fd >= 0)
                        close(fd);
                if (verbose >= 0)
                        pr_err("Cannot get exclusive access to %s:Perhaps a running process, mounted filesystem or active volume group?\n",
                               devname);
                return 1;
        }
        /* If this is an mdmon managed array, just write 'inactive'
         * to the array state and let mdmon clear up.
         */
        if (mdi &&
            mdi->array.level > 0 &&
            is_subarray(mdi->text_version)) {
                int err;
                /* This is mdmon managed. */
                close(fd);

                /* As we had an O_EXCL open, any use of the device
                 * which blocks STOP_ARRAY is probably a transient use,
                 * so it is reasonable to retry for a while - 5 seconds.
                 */
                count = 25;
                while (count &&
                       (err = sysfs_set_str(mdi, NULL,
                                            "array_state",
                                            "inactive")) < 0 &&
                       errno == EBUSY) {
                        sleep_for(0, MSEC_TO_NSEC(200), true);
                        count--;
                }
                if (err) {
                        if (verbose >= 0)
                                pr_err("failed to stop array %s: %s\n",
                                       devname, strerror(errno));
                        rv = 1;
                        goto out;
                }

                /* Give monitor a chance to act */
                ping_monitor(mdi->text_version);

                fd = open_dev_excl(devnm);
                if (fd < 0) {
                        if (verbose >= 0)
                                pr_err("failed to completely stop %s: Device is busy\n",
                                       devname);
                        rv = 1;
                        goto out;
                }
        } else if (mdi &&
                   mdi->array.major_version == -1 &&
                   mdi->array.minor_version == -2 &&
                   !is_subarray(mdi->text_version)) {
                struct mdstat_ent *mds, *m;
                /* container, possibly mdmon-managed.
                 * Make sure mdmon isn't opening it, which
                 * would interfere with the 'stop'
                 */
                ping_monitor(mdi->sys_name);

                /* now check that there are no existing arrays
                 * which are members of this array
                 */
                mds = mdstat_read(0, 0);
                for (m = mds; m; m = m->next)
                        if (m->metadata_version &&
                            strncmp(m->metadata_version, "external:", 9)==0 &&
                            metadata_container_matches(m->metadata_version+9,
                                                       devnm)) {
                                if (verbose >= 0)
                                        pr_err("Cannot stop container %s: member %s still active\n",
                                               devname, m->devnm);
                                free_mdstat(mds);
                                rv = 1;
                                goto out;
                        }
        }

        /* If the array is undergoing a reshape which changes the number
         * of devices, then it would be nice to stop it at a point where
         * it has completed a full number of stripes in both old and
         * new layouts as this will allow the reshape to be reverted.
         * So if 'sync_action' is "reshape" and 'raid_disks' shows two
         * different numbers, then
         *  - freeze reshape
         *  - set sync_max to next multiple of both data_disks and
         *    chunk sizes (or next but one)
         *  - unfreeze reshape
         *  - wait on 'sync_completed' for that point to be reached.
         */
        if (mdi && is_level456(mdi->array.level) &&
            sysfs_attribute_available(mdi, NULL, "sync_action") &&
            sysfs_attribute_available(mdi, NULL, "reshape_direction") &&
            sysfs_get_str(mdi, NULL, "sync_action", buf, 20) > 0 &&
            strcmp(buf, "reshape\n") == 0 &&
            sysfs_get_two(mdi, NULL, "raid_disks", &rd1, &rd2) == 2) {
                unsigned long long position, curr;
                unsigned long long chunk1, chunk2;
                unsigned long long rddiv, chunkdiv;
                unsigned long long sectors;
                unsigned long long sync_max, old_sync_max;
                unsigned long long completed;
                int backwards = 0;
                int delay;
                int scfd;

                delay = 40;
                while (rd1 > rd2 && delay > 0 &&
                       sysfs_get_ll(mdi, NULL, "sync_max", &old_sync_max) == 0) {
                        /* must be in the critical section - wait a bit */
                        delay -= 1;
                        sleep_for(0, MSEC_TO_NSEC(100), true);
                }

                if (sysfs_set_str(mdi, NULL, "sync_action", "frozen") != 0)
                        goto done;
                /* Array is frozen */

                rd1 -= mdi->array.level == 6 ? 2 : 1;
                rd2 -= mdi->array.level == 6 ? 2 : 1;
                sysfs_get_str(mdi, NULL, "reshape_direction", buf, sizeof(buf));
                if (strncmp(buf, "back", 4) == 0)
                        backwards = 1;
                if (sysfs_get_ll(mdi, NULL, "reshape_position", &position) != 0) {
                        /* reshape must have finished now */
                        sysfs_set_str(mdi, NULL, "sync_action", "idle");
                        goto done;
                }
                sysfs_get_two(mdi, NULL, "chunk_size", &chunk1, &chunk2);
                chunk1 /= 512;
                chunk2 /= 512;
                rddiv = GCD(rd1, rd2);
                chunkdiv = GCD(chunk1, chunk2);
                sectors = (chunk1/chunkdiv) * chunk2 * (rd1/rddiv) * rd2;

                if (backwards) {
                        /* Need to subtract 'reshape_position' from
                         * array size to get equivalent of sync_max.
                         * Size calculation based on raid5_size in kernel.
                         */
                        unsigned long long size = mdi->component_size;
                        size &= ~(chunk1-1);
                        size &= ~(chunk2-1);
                        /* rd1 must be smaller */
                        /* Reshape may have progressed further backwards than
                         * recorded, so target even further back (hence "-1")
                         */
                        position = (position / sectors - 1) * sectors;
                        /* rd1 is always the conversion factor between 'sync'
                         * position and 'reshape' position.
                         * We read 1 "new" stripe worth of data from where-ever,
                         * and when write out that full stripe.
                         */
                        sync_max = size - position/rd1;
                } else {
                        /* Reshape will very likely be beyond position, and it may
                         * be too late to stop at '+1', so aim for '+2'
                         */
                        position = (position / sectors + 2) * sectors;
                        sync_max = position/rd1;
                }
                if (sysfs_get_ll(mdi, NULL, "sync_max", &old_sync_max) < 0)
                        old_sync_max = mdi->component_size;
                /* Must not advance sync_max as that could confuse
                 * the reshape monitor */
                if (sync_max < old_sync_max)
                        sysfs_set_num(mdi, NULL, "sync_max", sync_max);
                sysfs_set_str(mdi, NULL, "sync_action", "idle");

                /* That should have set things going again.  Now we
                 * wait a little while (3 second max) for sync_completed
                 * to reach the target.
                 * The reshape process can block for 500msec if
                 * the sync speed limit is hit, so we need to wait
                 * a lot longer than that. 1 second is usually
                 * enough.  3 is safe.
                 */
                delay = 3000;
                scfd = sysfs_open(mdi->sys_name, NULL, "sync_completed");
                while (scfd >= 0 && delay > 0 && old_sync_max > 0) {
                        unsigned long long max_completed;
                        sysfs_get_ll(mdi, NULL, "reshape_position", &curr);
                        sysfs_fd_get_str(scfd, buf, sizeof(buf));
                        if (strncmp(buf, "none", 4) == 0) {
                                /* Either reshape has aborted, or hasn't
                                 * quite started yet.  Wait a bit and
                                 * check  'sync_action' to see.
                                 */
                                sleep_for(0, MSEC_TO_NSEC(10), true);
                                sysfs_get_str(mdi, NULL, "sync_action", buf, sizeof(buf));
                                if (strncmp(buf, "reshape", 7) != 0)
                                        break;
                        }

                        if (sysfs_fd_get_two(scfd, &completed,
                                             &max_completed) == 2 &&
                            /* 'completed' sometimes reads as max-uulong */
                            completed < max_completed &&
                            (completed > sync_max ||
                             (completed == sync_max && curr != position))) {
                                while (completed > sync_max) {
                                        sync_max += sectors / rd1;
                                        if (backwards)
                                                position -= sectors;
                                        else
                                                position += sectors;
                                }
                                if (sync_max < old_sync_max)
                                        sysfs_set_num(mdi, NULL, "sync_max", sync_max);
                        }

                        if (!backwards && curr >= position)
                                break;
                        if (backwards && curr <= position)
                                break;
                        sysfs_wait(scfd, &delay);
                }
                if (scfd >= 0)
                        close(scfd);

        }
done:

        /* As we have an O_EXCL open, any use of the device
         * which blocks STOP_ARRAY is probably a transient use,
         * so it is reasonable to retry for a while - 5 seconds.
         */
        count = 25; err = 0;
        while (count && fd >= 0 &&
               (err = ioctl(fd, STOP_ARRAY, NULL)) < 0 && errno == EBUSY) {
                sleep_for(0, MSEC_TO_NSEC(200), true);
                count --;
        }
        if (fd >= 0 && err) {
                if (verbose >= 0) {
                        pr_err("failed to stop array %s: %s\n",
                               devname, strerror(errno));
                        if (errno == EBUSY)
                                cont_err("Perhaps a running process, mounted filesystem or active volume group?\n");
                }
                rv = 1;
                goto out;
        }

        if (get_linux_version() < 2006028) {
                /* prior to 2.6.28, KOBJ_CHANGE was not sent when an md array
                 * was stopped, so We'll do it here just to be sure.  Drop any
                 * partitions as well...
                 */
                if (fd >= 0)
                        ioctl(fd, BLKRRPART, 0);
                if (mdi)
                        sysfs_uevent(mdi, "change");
        }

        if (devnm[0] && use_udev()) {
                struct map_ent *mp = map_by_devnm(&map, devnm);
                remove_devices(devnm, mp ? mp->path : NULL);
        }

        if (verbose >= 0)
                pr_err("stopped %s\n", devname);
        map_lock(&map);
        map_remove(&map, devnm);
        map_unlock(&map);
out:
        sysfs_free(mdi);

        return rv;
}

static struct mddev_dev *add_one(struct mddev_dev *dv, char *name, char disp)
{
        struct mddev_dev *new;
        new = xmalloc(sizeof(*new));
        memset(new, 0, sizeof(*new));
        new->devname = xstrdup(name);
        new->disposition = disp;
        new->next = dv->next;
        dv->next = new;
        return new;
}

static void add_faulty(struct mddev_dev *dv, int fd, char disp)
{
        mdu_array_info_t array;
        mdu_disk_info_t disk;
        int remaining_disks;
        int i;

        if (md_get_array_info(fd, &array) != 0)
                return;

        remaining_disks = array.nr_disks;
        for (i = 0; i < MAX_DISKS && remaining_disks > 0; i++) {
                char buf[40];
                disk.number = i;
                if (md_get_disk_info(fd, &disk) != 0)
                        continue;
                if (disk.major == 0 && disk.minor == 0)
                        continue;
                remaining_disks--;
                if ((disk.state & 1) == 0) /* not faulty */
                        continue;
                sprintf(buf, "%d:%d", disk.major, disk.minor);
                dv = add_one(dv, buf, disp);
        }
}

static void add_detached(struct mddev_dev *dv, int fd, char disp)
{
        mdu_array_info_t array;
        mdu_disk_info_t disk;
        int remaining_disks;
        int i;

        if (md_get_array_info(fd, &array) != 0)
                return;

        remaining_disks = array.nr_disks;
        for (i = 0; i < MAX_DISKS && remaining_disks > 0; i++) {
                char buf[40];
                int sfd;
                disk.number = i;
                if (md_get_disk_info(fd, &disk) != 0)
                        continue;
                if (disk.major == 0 && disk.minor == 0)
                        continue;
                remaining_disks--;
                if (disp == 'f' && (disk.state & 1) != 0) /* already faulty */
                        continue;
                sprintf(buf, "%d:%d", disk.major, disk.minor);
                sfd = dev_open(buf, O_RDONLY);
                if (sfd >= 0) {
                        /* Not detached */
                        close(sfd);
                        continue;
                }
                if (errno != ENXIO)
                        /* Probably not detached */
                        continue;
                dv = add_one(dv, buf, disp);
        }
}

static void add_set(struct mddev_dev *dv, int fd, char set_char)
{
        mdu_array_info_t array;
        mdu_disk_info_t disk;
        int remaining_disks;
        int copies, set;
        int i;

        if (md_get_array_info(fd, &array) != 0)
                return;
        if (array.level != 10)
                return;
        copies = ((array.layout & 0xff) *
                  ((array.layout >> 8) & 0xff));
        if (array.raid_disks % copies)
                return;

        remaining_disks = array.nr_disks;
        for (i = 0; i < MAX_DISKS && remaining_disks > 0; i++) {
                char buf[40];
                disk.number = i;
                if (md_get_disk_info(fd, &disk) != 0)
                        continue;
                if (disk.major == 0 && disk.minor == 0)
                        continue;
                remaining_disks--;
                set = disk.raid_disk % copies;
                if (set_char != set + 'A')
                        continue;
                sprintf(buf, "%d:%d", disk.major, disk.minor);
                dv = add_one(dv, buf, dv->disposition);
        }
}

int attempt_re_add(int fd, int tfd, struct mddev_dev *dv,
                   struct supertype *dev_st, struct supertype *tst,
                   unsigned long rdev,
                   char *update, char *devname, int verbose,
                   mdu_array_info_t *array)
{
        struct mdinfo mdi;
        int duuid[4];
        int ouuid[4];

        dev_st->ss->getinfo_super(dev_st, &mdi, NULL);
        dev_st->ss->uuid_from_super(dev_st, ouuid);
        if (tst->sb)
                tst->ss->uuid_from_super(tst, duuid);
        else
                /* Assume uuid matches: kernel will check */
                memcpy(duuid, ouuid, sizeof(ouuid));
        if ((mdi.disk.state & (1<<MD_DISK_ACTIVE)) &&
            !(mdi.disk.state & (1<<MD_DISK_FAULTY)) &&
            memcmp(duuid, ouuid, sizeof(ouuid))==0) {
                /* Looks like it is worth a
                 * try.  Need to make sure
                 * kernel will accept it
                 * though.
                 */
                mdu_disk_info_t disc;
                /* re-add doesn't work for version-1 superblocks
                 * before 2.6.18 :-(
                 */
                if (array->major_version == 1 &&
                    get_linux_version() <= 2006018)
                        goto skip_re_add;
                disc.number = mdi.disk.number;
                if (md_get_disk_info(fd, &disc) != 0 ||
                    disc.major != 0 || disc.minor != 0)
                        goto skip_re_add;
                disc.major = major(rdev);
                disc.minor = minor(rdev);
                disc.number = mdi.disk.number;
                disc.raid_disk = mdi.disk.raid_disk;
                disc.state = mdi.disk.state;
                if (array->state & (1 << MD_SB_CLUSTERED)) {
                        /* extra flags are needed when adding to a cluster as
                         * there are two cases to distinguish
                         */
                        if (dv->disposition == 'c')
                                disc.state |= (1 << MD_DISK_CANDIDATE);
                        else
                                disc.state |= (1 << MD_DISK_CLUSTER_ADD);
                }
                if (dv->writemostly == FlagSet)
                        disc.state |= 1 << MD_DISK_WRITEMOSTLY;
                if (dv->writemostly == FlagClear)
                        disc.state &= ~(1 << MD_DISK_WRITEMOSTLY);
                if (dv->failfast == FlagSet)
                        disc.state |= 1 << MD_DISK_FAILFAST;
                if (dv->failfast == FlagClear)
                        disc.state &= ~(1 << MD_DISK_FAILFAST);
                remove_partitions(tfd);
                if (update || dv->writemostly != FlagDefault ||
                    dv->failfast != FlagDefault) {
                        int rv = -1;
                        tfd = dev_open(dv->devname, O_RDWR);
                        if (tfd < 0) {
                                pr_err("failed to open %s for superblock update during re-add\n", dv->devname);
                                return -1;
                        }

                        if (dv->writemostly == FlagSet)
                                rv = dev_st->ss->update_super(
                                        dev_st, NULL, "writemostly",
                                        devname, verbose, 0, NULL);
                        if (dv->writemostly == FlagClear)
                                rv = dev_st->ss->update_super(
                                        dev_st, NULL, "readwrite",
                                        devname, verbose, 0, NULL);
                        if (dv->failfast == FlagSet)
                                rv = dev_st->ss->update_super(
                                        dev_st, NULL, "failfast",
                                        devname, verbose, 0, NULL);
                        if (dv->failfast == FlagClear)
                                rv = dev_st->ss->update_super(
                                        dev_st, NULL, "nofailfast",
                                        devname, verbose, 0, NULL);
                        if (update)
                                rv = dev_st->ss->update_super(
                                        dev_st, NULL, update,
                                        devname, verbose, 0, NULL);
                        if (rv == 0)
                                rv = dev_st->ss->store_super(dev_st, tfd);
                        close(tfd);
                        if (rv != 0) {
                                pr_err("failed to update superblock during re-add\n");
                                return -1;
                        }
                }
                /* don't even try if disk is marked as faulty */
                errno = 0;
                if (ioctl(fd, ADD_NEW_DISK, &disc) == 0) {
                        if (verbose >= 0)
                                pr_err("re-added %s\n", dv->devname);
                        return 1;
                }
                if (errno == ENOMEM || errno == EROFS) {
                        pr_err("add new device failed for %s: %s\n",
                               dv->devname, strerror(errno));
                        if (dv->disposition == 'M')
                                return 0;
                        return -1;
                }
        }
skip_re_add:
        return 0;
}

int Manage_add(int fd, int tfd, struct mddev_dev *dv,
               struct supertype *tst, mdu_array_info_t *array,
               int force, int verbose, char *devname,
               char *update, unsigned long rdev, unsigned long long array_size,
               int raid_slot)
{
        unsigned long long ldsize;
        struct supertype *dev_st;
        int j;
        mdu_disk_info_t disc;

        if (!get_dev_size(tfd, dv->devname, &ldsize)) {
                if (dv->disposition == 'M')
                        return 0;
                else
                        return -1;
        }

        if (tst->ss == &super0 && ldsize > 4ULL*1024*1024*1024*1024) {
                /* More than 4TB is wasted on v0.90 */
                if (!force) {
                        pr_err("%s is larger than %s can effectively use.\n"
                               "       Add --force is you really want to add this device.\n",
                               dv->devname, devname);
                        return -1;
                }
                pr_err("%s is larger than %s can effectively use.\n"
                       "       Adding anyway as --force was given.\n",
                       dv->devname, devname);
        }

        if (array->not_persistent == 0 || tst->ss->external) {

                /* need to find a sample superblock to copy, and
                 * a spare slot to use.
                 * For 'external' array (well, container based),
                 * We can just load the metadata for the array->
                 */
                int array_failed;
                if (tst->sb)
                        /* already loaded */;
                else if (tst->ss->external) {
                        tst->ss->load_container(tst, fd, NULL);
                } else for (j = 0; j < tst->max_devs; j++) {
                                char *dev;
                                int dfd;
                                disc.number = j;
                                if (md_get_disk_info(fd, &disc))
                                        continue;
                                if (disc.major==0 && disc.minor==0)
                                        continue;
                                if ((disc.state & 4)==0) /* sync */
                                        continue;
                                /* Looks like a good device to try */
                                dev = map_dev(disc.major, disc.minor, 1);
                                if (!dev)
                                        continue;
                                dfd = dev_open(dev, O_RDONLY);
                                if (dfd < 0)
                                        continue;
                                if (tst->ss->load_super(tst, dfd,
                                                        NULL)) {
                                        close(dfd);
                                        continue;
                                }
                                close(dfd);
                                break;
                        }
                /* FIXME this is a bad test to be using */
                if (!tst->sb && (dv->disposition != 'a' &&
                                 dv->disposition != 'S')) {
                        /* we are re-adding a device to a
                         * completely dead array - have to depend
                         * on kernel to check
                         */
                } else if (!tst->sb) {
                        pr_err("cannot load array metadata from %s\n", devname);
                        return -1;
                }

                /* Make sure device is large enough */
                if (dv->disposition != 'j' &&  /* skip size check for Journal */
                    tst->sb &&
                    tst->ss->avail_size(tst, ldsize/512, INVALID_SECTORS) <
                    array_size) {
                        if (dv->disposition == 'M')
                                return 0;
                        pr_err("%s not large enough to join array\n",
                               dv->devname);
                        return -1;
                }

                /* Possibly this device was recently part of
                 * the array and was temporarily removed, and
                 * is now being re-added.  If so, we can
                 * simply re-add it.
                 */

                if (array->not_persistent == 0) {
                        dev_st = dup_super(tst);
                        dev_st->ss->load_super(dev_st, tfd, NULL);
                        if (dev_st->sb && dv->disposition != 'S') {
                                int rv;

                                rv = attempt_re_add(fd, tfd, dv, dev_st, tst,
                                                    rdev, update, devname,
                                                    verbose, array);
                                dev_st->ss->free_super(dev_st);
                                if (rv)
                                        return rv;
                        }
                }
                if (dv->disposition == 'M') {
                        if (verbose > 0)
                                pr_err("--re-add for %s to %s is not possible\n",
                                       dv->devname, devname);
                        return 0;
                }
                if (dv->disposition == 'A') {
                        pr_err("--re-add for %s to %s is not possible\n",
                               dv->devname, devname);
                        return -1;
                }
                if (array->active_disks < array->raid_disks) {
                        char *avail = xcalloc(array->raid_disks, 1);
                        int d;
                        int found = 0;

                        for (d = 0; d < MAX_DISKS && found < array->nr_disks; d++) {
                                disc.number = d;
                                if (md_get_disk_info(fd, &disc))
                                        continue;
                                if (disc.major == 0 && disc.minor == 0)
                                        continue;
                                if (!(disc.state & (1<<MD_DISK_SYNC)))
                                        continue;
                                avail[disc.raid_disk] = 1;
                                found++;
                        }
                        array_failed = !enough(array->level, array->raid_disks,
                                               array->layout, 1, avail);
                        free(avail);
                } else
                        array_failed = 0;
                if (array_failed) {
                        pr_err("%s has failed so using --add cannot work and might destroy\n",
                               devname);
                        pr_err("data on %s.  You should stop the array and re-assemble it.\n",
                               dv->devname);
                        return -1;
                }
        } else {
                /* non-persistent. Must ensure that new drive
                 * is at least array->size big.
                 */
                if (ldsize/512 < array_size) {
                        pr_err("%s not large enough to join array\n",
                               dv->devname);
                        return -1;
                }
        }
        /* committed to really trying this device now*/
        remove_partitions(tfd);

        /* in 2.6.17 and earlier, version-1 superblocks won't
         * use the number we write, but will choose a free number.
         * we must choose the same free number, which requires
         * starting at 'raid_disks' and counting up
         */
        for (j = array->raid_disks; j < tst->max_devs; j++) {
                disc.number = j;
                if (md_get_disk_info(fd, &disc))
                        break;
                if (disc.major==0 && disc.minor==0)
                        break;
                if (disc.state & 8) /* removed */
                        break;
        }
        disc.major = major(rdev);
        disc.minor = minor(rdev);
        if (raid_slot < 0)
                disc.number = j;
        else
                disc.number = raid_slot;
        disc.state = 0;

        /* only add journal to array that supports journaling */
        if (dv->disposition == 'j') {
                struct mdinfo *mdp;

                mdp = sysfs_read(fd, NULL, GET_ARRAY_STATE);
                if (!mdp) {
                        pr_err("%s unable to read array state.\n", devname);
                        return -1;
                }

                if (mdp->array_state != ARRAY_READONLY) {
                        sysfs_free(mdp);
                        pr_err("%s is not readonly, cannot add journal.\n", devname);
                        return -1;
                }

                sysfs_free(mdp);

                disc.raid_disk = 0;
        }

        if (array->not_persistent==0) {
                int dfd;
                if (dv->disposition == 'j')
                        disc.state |= (1 << MD_DISK_JOURNAL) | (1 << MD_DISK_SYNC);
                if (dv->writemostly == FlagSet)
                        disc.state |= 1 << MD_DISK_WRITEMOSTLY;
                if (dv->failfast == FlagSet)
                        disc.state |= 1 << MD_DISK_FAILFAST;
                dfd = dev_open(dv->devname, O_RDWR | O_EXCL|O_DIRECT);
                if (tst->ss->add_to_super(tst, &disc, dfd,
                                          dv->devname, INVALID_SECTORS))
                        return -1;
                if (tst->ss->write_init_super(tst))
                        return -1;
        } else if (dv->disposition == 'A') {
                /*  this had better be raid1.
                 * As we are "--re-add"ing we must find a spare slot
                 * to fill.
                 */
                char *used = xcalloc(array->raid_disks, 1);
                for (j = 0; j < tst->max_devs; j++) {
                        mdu_disk_info_t disc2;
                        disc2.number = j;
                        if (md_get_disk_info(fd, &disc2))
                                continue;
                        if (disc2.major==0 && disc2.minor==0)
                                continue;
                        if (disc2.state & 8) /* removed */
                                continue;
                        if (disc2.raid_disk < 0)
                                continue;
                        if (disc2.raid_disk > array->raid_disks)
                                continue;
                        used[disc2.raid_disk] = 1;
                }
                for (j = 0 ; j < array->raid_disks; j++)
                        if (!used[j]) {
                                disc.raid_disk = j;
                                disc.state |= (1<<MD_DISK_SYNC);
                                break;
                        }
                free(used);
        }

        if (array->state & (1 << MD_SB_CLUSTERED)) {
                if (dv->disposition == 'c')
                        disc.state |= (1 << MD_DISK_CANDIDATE);
                else
                        disc.state |= (1 << MD_DISK_CLUSTER_ADD);
        }

        if (dv->writemostly == FlagSet)
                disc.state |= (1 << MD_DISK_WRITEMOSTLY);
        if (dv->failfast == FlagSet)
                disc.state |= (1 << MD_DISK_FAILFAST);
        if (tst->ss->external) {
                /* add a disk
                 * to an external metadata container */
                struct mdinfo new_mdi;
                struct mdinfo *sra;
                int container_fd;
                char devnm[32];
                int dfd;

                strcpy(devnm, fd2devnm(fd));

                container_fd = open_dev_excl(devnm);
                if (container_fd < 0) {
                        pr_err("add failed for %s: could not get exclusive access to container\n",
                               dv->devname);
                        tst->ss->free_super(tst);
                        return -1;
                }

                /* Check if metadata handler is able to accept the drive */
                if (!tst->ss->validate_geometry(tst, LEVEL_CONTAINER, 0, 1, NULL,
                    0, 0, dv->devname, NULL, 0, 1)) {
                        close(container_fd);
                        return -1;
                }

                Kill(dv->devname, NULL, 0, -1, 0);
                dfd = dev_open(dv->devname, O_RDWR | O_EXCL|O_DIRECT);
                if (tst->ss->add_to_super(tst, &disc, dfd,
                                          dv->devname, INVALID_SECTORS)) {
                        close(dfd);
                        close(container_fd);
                        return -1;
                }
                if (!mdmon_running(tst->container_devnm))
                        tst->ss->sync_metadata(tst);

                sra = sysfs_read(container_fd, NULL, 0);
                if (!sra) {
                        pr_err("add failed for %s: sysfs_read failed\n",
                               dv->devname);
                        close(container_fd);
                        tst->ss->free_super(tst);
                        return -1;
                }
                sra->array.level = LEVEL_CONTAINER;
                /* Need to set data_offset and component_size */
                tst->ss->getinfo_super(tst, &new_mdi, NULL);
                new_mdi.disk.major = disc.major;
                new_mdi.disk.minor = disc.minor;
                new_mdi.recovery_start = 0;
                /* Make sure fds are closed as they are O_EXCL which
                 * would block add_disk */
                tst->ss->free_super(tst);
                if (sysfs_add_disk(sra, &new_mdi, 0) != 0) {
                        pr_err("add new device to external metadata failed for %s\n", dv->devname);
                        close(container_fd);
                        sysfs_free(sra);
                        return -1;
                }
                ping_monitor(devnm);
                sysfs_free(sra);
                close(container_fd);
        } else {
                tst->ss->free_super(tst);
                if (ioctl(fd, ADD_NEW_DISK, &disc)) {
                        if (dv->disposition == 'j')
                                pr_err("Failed to hot add %s as journal, "
                                       "please try restart %s.\n", dv->devname, devname);
                        else
                                pr_err("add new device failed for %s as %d: %s\n",
                                       dv->devname, j, strerror(errno));
                        return -1;
                }
                if (dv->disposition == 'j') {
                        pr_err("Journal added successfully, making %s read-write\n", devname);
                        if (Manage_ro(devname, fd, -1))
                                pr_err("Failed to make %s read-write\n", devname);
                }

        }
        if (verbose >= 0)
                pr_err("added %s\n", dv->devname);
        return 1;
}

int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
                  int sysfd, unsigned long rdev, int force, int verbose, char *devname)
{
        int lfd = -1;
        int err;

        if (tst->ss->external) {
                /* To remove a device from a container, we must
                 * check that it isn't in use in an array.
                 * This involves looking in the 'holders'
                 * directory - there must be just one entry,
                 * the container.
                 * To ensure that it doesn't get used as a
                 * hot spare while we are checking, we
                 * get an O_EXCL open on the container
                 */
                int ret;
                char devnm[32];
                strcpy(devnm, fd2devnm(fd));
                lfd = open_dev_excl(devnm);
                if (lfd < 0) {
                        pr_err("Cannot get exclusive access  to container - odd\n");
                        return -1;
                }
                /* We may not be able to check on holders in
                 * sysfs, either because we don't have the dev num
                 * (rdev == 0) or because the device has been detached
                 * and the 'holders' directory no longer exists
                 * (ret == -1).  In that case, assume it is OK to
                 * remove.
                 */
                if (rdev == 0)
                        ret = -1;
                else {
                        /*
                         * The drive has already been set to 'faulty', however
                         * monitor might not have had time to process it and the
                         * drive might still have an entry in the 'holders'
                         * directory. Try a few times to avoid a false error
                         */
                        int count = 20;

                        do {
                                ret = sysfs_unique_holder(devnm, rdev);
                                if (ret < 2)
                                        break;
                                sleep_for(0, MSEC_TO_NSEC(100), true);
                        } while (--count > 0);

                        if (ret == 0) {
                                pr_err("%s is not a member, cannot remove.\n",
                                        dv->devname);
                                close(lfd);
                                return -1;
                        }
                        if (ret >= 2) {
                                pr_err("%s is still in use, cannot remove.\n",
                                        dv->devname);
                                close(lfd);
                                return -1;
                        }
                }
        }
        /* FIXME check that it is a current member */
        if (sysfd >= 0) {
                /* device has been removed and we don't know
                 * the major:minor number
                 */
                err = sys_hot_remove_disk(sysfd, force);
        } else {
                err = hot_remove_disk(fd, rdev, force);
                if (err && errno == ENODEV) {
                        /* Old kernels rejected this if no personality
                         * is registered */
                        struct mdinfo *sra = sysfs_read(fd, NULL, GET_DEVS);
                        struct mdinfo *dv = NULL;
                        if (sra)
                                dv = sra->devs;
                        for ( ; dv ; dv=dv->next)
                                if (dv->disk.major == (int)major(rdev) &&
                                    dv->disk.minor == (int)minor(rdev))
                                        break;
                        if (dv)
                                err = sysfs_set_str(sra, dv,
                                                    "state", "remove");
                        else
                                err = -1;
                        sysfs_free(sra);
                }
        }
        if (err) {
                pr_err("hot remove failed for %s: %s\n",        dv->devname,
                       strerror(errno));
                if (lfd >= 0)
                        close(lfd);
                return -1;
        }
        if (tst->ss->external) {
                /*
                 * Before dropping our exclusive open we make an
                 * attempt at preventing mdmon from seeing an
                 * 'add' event before reconciling this 'remove'
                 * event.
                 */
                char *devnm = fd2devnm(fd);

                if (!devnm) {
                        pr_err("unable to get container name\n");
                        return -1;
                }

                ping_manager(devnm);
        }
        if (lfd >= 0)
                close(lfd);
        if (verbose >= 0)
                pr_err("hot removed %s from %s\n",
                       dv->devname, devname);
        return 1;
}

int Manage_replace(struct supertype *tst, int fd, struct mddev_dev *dv,
                   unsigned long rdev, int verbose, char *devname)
{
        struct mdinfo *mdi, *di;
        if (tst->ss->external) {
                pr_err("--replace only supported for native metadata (0.90 or 1.x)\n");
                return -1;
        }
        /* Need to find the device in sysfs and add 'want_replacement' to the
         * status.
         */
        mdi = sysfs_read(fd, NULL, GET_DEVS);
        if (!mdi || !mdi->devs) {
                pr_err("Cannot find status of %s to enable replacement - strange\n",
                       devname);
                return -1;
        }
        for (di = mdi->devs; di; di = di->next)
                if (di->disk.major == (int)major(rdev) &&
                    di->disk.minor == (int)minor(rdev))
                        break;
        if (di) {
                int rv;
                if (di->disk.raid_disk < 0) {
                        pr_err("%s is not active and so cannot be replaced.\n",
                               dv->devname);
                        sysfs_free(mdi);
                        return -1;
                }
                rv = sysfs_set_str(mdi, di,
                                   "state", "want_replacement");
                if (rv) {
                        sysfs_free(mdi);
                        pr_err("Failed to request replacement for %s\n",
                               dv->devname);
                        return -1;
                }
                if (verbose >= 0)
                        pr_err("Marked %s (device %d in %s) for replacement\n",
                               dv->devname, di->disk.raid_disk, devname);
                /* If there is a matching 'with', we need to tell it which
                 * raid disk
                 */
                while (dv && dv->disposition != 'W')
                        dv = dv->next;
                if (dv) {
                        dv->disposition = 'w';
                        dv->used = di->disk.raid_disk;
                }
                return 1;
        }
        sysfs_free(mdi);
        pr_err("%s not found in %s so cannot --replace it\n",
               dv->devname, devname);
        return -1;
}

int Manage_with(struct supertype *tst, int fd, struct mddev_dev *dv,
                unsigned long rdev, int verbose, char *devname)
{
        struct mdinfo *mdi, *di;
        /* try to set 'slot' for 'rdev' in 'fd' to 'dv->used' */
        mdi = sysfs_read(fd, NULL, GET_DEVS|GET_STATE);
        if (!mdi || !mdi->devs) {
                pr_err("Cannot find status of %s to enable replacement - strange\n",
                       devname);
                return -1;
        }
        for (di = mdi->devs; di; di = di->next)
                if (di->disk.major == (int)major(rdev) &&
                    di->disk.minor == (int)minor(rdev))
                        break;
        if (di) {
                int rv;
                if (di->disk.state & (1<<MD_DISK_FAULTY)) {
                        pr_err("%s is faulty and cannot be a replacement\n",
                               dv->devname);
                        sysfs_free(mdi);
                        return -1;
                }
                if (di->disk.raid_disk >= 0) {
                        pr_err("%s is active and cannot be a replacement\n",
                               dv->devname);
                        sysfs_free(mdi);
                        return -1;
                }
                rv = sysfs_set_num(mdi, di,
                                   "slot", dv->used);
                if (rv) {
                        sysfs_free(mdi);
                        pr_err("Failed to set %s as preferred replacement.\n",
                               dv->devname);
                        return -1;
                }
                if (verbose >= 0)
                        pr_err("Marked %s in %s as replacement for device %d\n",
                               dv->devname, devname, dv->used);
                return 1;
        }
        sysfs_free(mdi);
        pr_err("%s not found in %s so cannot make it preferred replacement\n",
               dv->devname, devname);
        return -1;
}

/**
 * is_remove_safe() - Check if remove is safe.
 * @array: Array info.
 * @fd: Array file descriptor.
 * @devname: Name of device to remove.
 * @verbose: Verbose.
 *
 * The function determines if array will be operational
 * after removing &devname.
 *
 * Return: True if array will be operational, false otherwise.
 */
bool is_remove_safe(mdu_array_info_t *array, const int fd, char *devname, const int verbose)
{
        dev_t devid = devnm2devid(devname + 5);
        struct mdinfo *mdi = sysfs_read(fd, NULL, GET_DEVS | GET_DISKS | GET_STATE);

        if (!mdi) {
                if (verbose)
                        pr_err("Failed to read sysfs attributes for %s\n", devname);
                return false;
        }

        char *avail = xcalloc(array->raid_disks, sizeof(char));

        for (mdi = mdi->devs; mdi; mdi = mdi->next) {
                if (mdi->disk.raid_disk < 0)
                        continue;
                if (!(mdi->disk.state & (1 << MD_DISK_SYNC)))
                        continue;
                if (makedev(mdi->disk.major, mdi->disk.minor) == devid)
                        continue;
                avail[mdi->disk.raid_disk] = 1;
        }
        sysfs_free(mdi);

        bool is_enough = enough(array->level, array->raid_disks,
                                array->layout, (array->state & 1),
                                avail);

        free(avail);
        return is_enough;
}

int Manage_subdevs(char *devname, int fd,
                   struct mddev_dev *devlist, int verbose, int test,
                   char *update, int force)
{
        /* Do something to each dev.
         * devmode can be
         *  'a' - add the device
         *  'S' - add the device as a spare - don't try re-add
         *  'j' - add the device as a journal device
         *  'A' - re-add the device
         *  'r' - remove the device: HOT_REMOVE_DISK
         *        device can be 'faulty' or 'detached' in which case all
         *        matching devices are removed.
         *  'f' - set the device faulty SET_DISK_FAULTY
         *        device can be 'detached' in which case any device that
         *        is inaccessible will be marked faulty.
         *  'R' - mark this device as wanting replacement.
         *  'W' - this device is added if necessary and activated as
         *        a replacement for a previous 'R' device.
         * -----
         *  'w' - 'W' will be changed to 'w' when it is paired with
         *        a 'R' device.  If a 'W' is found while walking the list
         *        it must be unpaired, and is an error.
         *  'M' - this is created by a 'missing' target.  It is a slight
         *        variant on 'A'
         *  'F' - Another variant of 'A', where the device was faulty
         *        so must be removed from the array first.
         *  'c' - confirm the device as found (for clustered environments)
         *
         * For 'f' and 'r', the device can also be a kernel-internal
         * name such as 'sdb'.
         */
        mdu_array_info_t array;
        unsigned long long array_size;
        struct mddev_dev *dv;
        int tfd = -1;
        struct supertype *tst;
        char *subarray = NULL;
        int sysfd = -1;
        int count = 0; /* number of actions taken */
        struct mdinfo info;
        struct mdinfo devinfo;
        int frozen = 0;
        int busy = 0;
        int raid_slot = -1;

        if (sysfs_init(&info, fd, NULL)) {
                pr_err("sysfs not availabile for %s\n", devname);
                goto abort;
        }

        if (md_get_array_info(fd, &array)) {
                pr_err("Cannot get array info for %s\n", devname);
                goto abort;
        }
        /* array.size is only 32 bits and may be truncated.
         * So read from sysfs if possible, and record number of sectors
         */

        array_size = get_component_size(fd);
        if (array_size <= 0)
                array_size = array.size * 2;

        tst = super_by_fd(fd, &subarray);
        if (!tst) {
                pr_err("unsupport array - version %d.%d\n",
                        array.major_version, array.minor_version);
                goto abort;
        }

        for (dv = devlist; dv; dv = dv->next) {
                dev_t rdev = 0; /* device to add/remove etc */
                int rv;
                int mj,mn;

                raid_slot = -1;
                if (dv->disposition == 'c') {
                        rv = parse_cluster_confirm_arg(dv->devname,
                                                       &dv->devname,
                                                       &raid_slot);
                        if (rv) {
                                pr_err("Could not get the devname of cluster\n");
                                goto abort;
                        }
                }

                if (strcmp(dv->devname, "failed") == 0 ||
                    strcmp(dv->devname, "faulty") == 0) {
                        if (dv->disposition != 'A' && dv->disposition != 'r') {
                                pr_err("%s only meaningful with -r or --re-add, not -%c\n",
                                        dv->devname, dv->disposition);
                                goto abort;
                        }
                        add_faulty(dv, fd, (dv->disposition == 'A'
                                            ? 'F' : 'r'));
                        continue;
                }
                if (strcmp(dv->devname, "detached") == 0) {
                        if (dv->disposition != 'r' && dv->disposition != 'f') {
                                pr_err("%s only meaningful with -r of -f, not -%c\n",
                                        dv->devname, dv->disposition);
                                goto abort;
                        }
                        add_detached(dv, fd, dv->disposition);
                        continue;
                }

                if (strcmp(dv->devname, "missing") == 0) {
                        struct mddev_dev *add_devlist;
                        struct mddev_dev **dp;
                        if (dv->disposition == 'c') {
                                rv = ioctl(fd, CLUSTERED_DISK_NACK, NULL);
                                break;
                        }

                        if (dv->disposition != 'A') {
                                pr_err("'missing' only meaningful with --re-add\n");
                                goto abort;
                        }
                        add_devlist = conf_get_devs();
                        if (add_devlist == NULL) {
                                pr_err("no devices to scan for missing members.\n");
                                continue;
                        }
                        for (dp = &add_devlist; *dp; dp = & (*dp)->next)
                                /* 'M' (for 'missing') is like 'A' without errors */
                                (*dp)->disposition = 'M';
                        *dp = dv->next;
                        dv->next = add_devlist;
                        continue;
                }

                if (strncmp(dv->devname, "set-", 4) == 0 &&
                    strlen(dv->devname) == 5) {
                        int copies;

                        if (dv->disposition != 'r' &&
                            dv->disposition != 'f') {
                                pr_err("'%s' only meaningful with -r or -f\n",
                                       dv->devname);
                                goto abort;
                        }
                        if (array.level != 10) {
                                pr_err("'%s' only meaningful with RAID10 arrays\n",
                                       dv->devname);
                                goto abort;
                        }
                        copies = ((array.layout & 0xff) *
                                  ((array.layout >> 8) & 0xff));
                        if (array.raid_disks % copies != 0 ||
                            dv->devname[4] < 'A' ||
                            dv->devname[4] >= 'A' + copies ||
                            copies > 26) {
                                pr_err("'%s' not meaningful with this array\n",
                                       dv->devname);
                                goto abort;
                        }
                        add_set(dv, fd, dv->devname[4]);
                        continue;
                }

                if (strchr(dv->devname, '/') == NULL &&
                    strchr(dv->devname, ':') == NULL &&
                    strlen(dv->devname) < 50) {
                        /* Assume this is a kernel-internal name like 'sda1' */
                        int found = 0;
                        char dname[55];
                        if (dv->disposition != 'r' && dv->disposition != 'f') {
                                pr_err("%s only meaningful with -r or -f, not -%c\n",
                                        dv->devname, dv->disposition);
                                goto abort;
                        }

                        sprintf(dname, "dev-%s", dv->devname);
                        sysfd = sysfs_open(fd2devnm(fd), dname, "block/dev");
                        if (sysfd >= 0) {
                                char dn[20];
                                if (sysfs_fd_get_str(sysfd, dn, 20) > 0 &&
                                    sscanf(dn, "%d:%d", &mj,&mn) == 2) {
                                        rdev = makedev(mj,mn);
                                        found = 1;
                                }
                                close(sysfd);
                                sysfd = -1;
                        }
                        if (!found) {
                                sysfd = sysfs_open(fd2devnm(fd), dname, "state");
                                if (sysfd < 0) {
                                        pr_err("%s does not appear to be a component of %s\n",
                                                dv->devname, devname);
                                        goto abort;
                                }
                        }
                } else if ((dv->disposition == 'r' ||
                            dv->disposition == 'f') &&
                           get_maj_min(dv->devname, &mj, &mn)) {
                        /* for 'fail' and 'remove', the device might
                         * not exist.
                         */
                        rdev = makedev(mj, mn);
                } else {
                        tfd = dev_open(dv->devname, O_RDONLY);
                        if (tfd >= 0) {
                                fstat_is_blkdev(tfd, dv->devname, &rdev);
                                close(tfd);
                        } else {
                                int open_err = errno;
                                if (!stat_is_blkdev(dv->devname, &rdev)) {
                                        if (dv->disposition == 'M')
                                                /* non-fatal. Also improbable */
                                                continue;
                                        goto abort;
                                }
                                if (dv->disposition == 'r')
                                        /* Be happy, the stat worked, that is
                                         * enough for --remove
                                         */
                                        ;
                                else {
                                        if (dv->disposition == 'M')
                                                /* non-fatal */
                                                continue;
                                        pr_err("Cannot open %s: %s\n",
                                               dv->devname, strerror(open_err));
                                        goto abort;
                                }
                        }
                }
                switch(dv->disposition){
                default:
                        pr_err("internal error - devmode[%s]=%d\n",
                                dv->devname, dv->disposition);
                        goto abort;
                case 'a':
                case 'S': /* --add-spare */
                case 'j': /* --add-journal */
                case 'A':
                case 'M': /* --re-add missing */
                case 'F': /* --re-add faulty  */
                case 'c': /* --cluster-confirm */
                        /* add the device */
                        if (subarray) {
                                pr_err("Cannot add disks to a \'member\' array, perform this operation on the parent container\n");
                                goto abort;
                        }

                        /* Let's first try to write re-add to sysfs */
                        if (rdev != 0 &&
                            (dv->disposition == 'A' || dv->disposition == 'F')) {
                                sysfs_init_dev(&devinfo, rdev);
                                if (sysfs_set_str(&info, &devinfo, "state", "re-add") == 0) {
                                        pr_err("re-add %s to %s succeed\n",
                                                dv->devname, info.sys_name);
                                        break;
                                }
                        }

                        if (dv->disposition == 'F')
                                /* Need to remove first */
                                hot_remove_disk(fd, rdev, force);
                        /* Make sure it isn't in use (in 2.6 or later) */
                        tfd = dev_open(dv->devname, O_RDONLY|O_EXCL);
                        if (tfd >= 0) {
                                /* We know no-one else is using it.  We'll
                                 * need non-exclusive access to add it, so
                                 * do that now.
                                 */
                                close(tfd);
                                tfd = dev_open(dv->devname, O_RDONLY);
                        }
                        if (tfd < 0) {
                                if (dv->disposition == 'M')
                                        continue;
                                pr_err("Cannot open %s: %s\n",
                                        dv->devname, strerror(errno));
                                goto abort;
                        }
                        if (!frozen) {
                                if (sysfs_freeze_array(&info) == 1)
                                        frozen = 1;
                                else
                                        frozen = -1;
                        }
                        rv = Manage_add(fd, tfd, dv, tst, &array,
                                        force, verbose, devname, update,
                                        rdev, array_size, raid_slot);
                        close(tfd);
                        tfd = -1;
                        if (rv < 0)
                                goto abort;
                        if (rv > 0)
                                count++;
                        break;

                case 'r':
                        /* hot remove */
                        if (subarray) {
                                pr_err("Cannot remove disks from a \'member\' array, perform this operation on the parent container\n");
                                rv = -1;
                        } else
                                rv = Manage_remove(tst, fd, dv, sysfd,
                                                   rdev, verbose, force,
                                                   devname);
                        if (sysfd >= 0)
                                close(sysfd);
                        sysfd = -1;
                        if (rv < 0)
                                goto abort;
                        if (rv > 0)
                                count++;
                        break;

                case 'f': /* set faulty */
                        if (!is_remove_safe(&array, fd, dv->devname, verbose)) {
                                pr_err("Cannot remove %s from %s, array will be failed.\n",
                                       dv->devname, devname);
                                if (sysfd >= 0)
                                        close(sysfd);
                                goto abort;
                        }

                        if ((sysfd >= 0 && write(sysfd, "faulty", 6) != 6) ||
                            (sysfd < 0 && ioctl(fd, SET_DISK_FAULTY,
                                                rdev))) {
                                if (errno == EBUSY)
                                        busy = 1;
                                pr_err("set device faulty failed for %s:  %s\n",
                                        dv->devname, strerror(errno));
                                if (sysfd >= 0)
                                        close(sysfd);
                                goto abort;
                        }
                        if (sysfd >= 0)
                                close(sysfd);
                        sysfd = -1;
                        count++;
                        if (verbose >= 0)
                                pr_err("set %s faulty in %s\n",
                                        dv->devname, devname);
                        break;
                case 'R': /* Mark as replaceable */
                        if (subarray) {
                                pr_err("Cannot replace disks in a \'member\' array, perform this operation on the parent container\n");
                                rv = -1;
                        } else {
                                if (!frozen) {
                                        if (sysfs_freeze_array(&info) == 1)
                                                frozen = 1;
                                        else
                                                frozen = -1;
                                }
                                rv = Manage_replace(tst, fd, dv,
                                                    rdev, verbose,
                                                    devname);
                        }
                        if (rv < 0)
                                goto abort;
                        if (rv > 0)
                                count++;
                        break;
                case 'W': /* --with device that doesn't match */
                        pr_err("No matching --replace device for --with %s\n",
                               dv->devname);
                        goto abort;
                case 'w': /* --with device which was matched */
                        rv = Manage_with(tst, fd, dv,
                                         rdev, verbose, devname);
                        if (rv < 0)
                                goto abort;
                        break;
                }
        }
        if (frozen > 0)
                sysfs_set_str(&info, NULL, "sync_action","idle");
        if (test && count == 0)
                return 2;
        return 0;

abort:
        if (frozen > 0)
                sysfs_set_str(&info, NULL, "sync_action","idle");
        return !test && busy ? 2 : 1;
}

int autodetect(void)
{
        /* Open any md device, and issue the RAID_AUTORUN ioctl */
        int rv = 1;
        int fd = dev_open("9:0", O_RDONLY);
        if (fd >= 0) {
                if (ioctl(fd, RAID_AUTORUN, 0) == 0)
                        rv = 0;
                close(fd);
        }
        return rv;
}

int Update_subarray(char *dev, char *subarray, char *update, struct mddev_ident *ident, int verbose)
{
        struct supertype supertype, *st = &supertype;
        int fd, rv = 2;
        struct mdinfo *info = NULL;

        memset(st, 0, sizeof(*st));

        fd = open_subarray(dev, subarray, st, verbose < 0);
        if (fd < 0)
                return 2;

        if (!st->ss->update_subarray) {
                if (verbose >= 0)
                        pr_err("Operation not supported for %s metadata\n",
                               st->ss->name);
                goto free_super;
        }

        if (mdmon_running(st->devnm))
                st->update_tail = &st->updates;

        info = st->ss->container_content(st, subarray);

        if (strncmp(update, "ppl", 3) == 0 && !is_level456(info->array.level)) {
                pr_err("RWH policy ppl is supported only for raid4, raid5 and raid6.\n");
                goto free_super;
        }

        rv = st->ss->update_subarray(st, subarray, update, ident);

        if (rv) {
                if (verbose >= 0)
                        pr_err("Failed to update %s of subarray-%s in %s\n",
                                update, subarray, dev);
        } else if (st->update_tail)
                flush_metadata_updates(st);
        else
                st->ss->sync_metadata(st);

        if (rv == 0 && strcmp(update, "name") == 0 && verbose >= 0)
                pr_err("Updated subarray-%s name from %s, UUIDs may have changed\n",
                       subarray, dev);

free_super:
        if (info)
                free(info);
        st->ss->free_super(st);
        close(fd);

        return rv;
}

/* Move spare from one array to another If adding to destination array fails
 * add back to original array.
 * Returns 1 on success, 0 on failure */
int move_spare(char *from_devname, char *to_devname, dev_t devid)
{
        struct mddev_dev devlist;
        char devname[20];

        /* try to remove and add */
        int fd1 = open(to_devname, O_RDONLY);
        int fd2 = open(from_devname, O_RDONLY);

        if (fd1 < 0 || fd2 < 0) {
                if (fd1 >= 0)
                        close(fd1);
                if (fd2 >= 0)
                        close(fd2);
                return 0;
        }

        devlist.next = NULL;
        devlist.used = 0;
        devlist.writemostly = FlagDefault;
        devlist.failfast = FlagDefault;
        devlist.devname = devname;
        sprintf(devname, "%d:%d", major(devid), minor(devid));

        devlist.disposition = 'r';
        if (Manage_subdevs(from_devname, fd2, &devlist, -1, 0, NULL, 0) == 0) {
                devlist.disposition = 'a';
                if (Manage_subdevs(to_devname, fd1, &devlist, -1, 0,
                                   NULL, 0) == 0) {
                        /* make sure manager is aware of changes */
                        ping_manager(to_devname);
                        ping_manager(from_devname);
                        close(fd1);
                        close(fd2);
                        return 1;
                }
                else
                        Manage_subdevs(from_devname, fd2, &devlist,
                                       -1, 0, NULL, 0);
        }
        close(fd1);
        close(fd2);
        return 0;
}