]> git.ipfire.org Git - thirdparty/mdadm.git/blobdiff - super-intel.c
Factor out test for subarray version string.
[thirdparty/mdadm.git] / super-intel.c
index 6992eeb7bfa981d69e2c25ae856a6c8b6eaf636e..b78b5294aa7ceaf434a2c13f3ac052398311f58c 100644 (file)
@@ -68,8 +68,10 @@ struct imsm_map {
        __u8  num_members;      /* number of member disks */
        __u8  reserved[3];
        __u32 filler[7];        /* expansion area */
+#define IMSM_ORD_REBUILD (1 << 24)
        __u32 disk_ord_tbl[1];  /* disk_ord_tbl[num_members],
-                                  top byte special */
+                                * top byte contains some flags
+                                */
 } __attribute__ ((packed));
 
 struct imsm_vol {
@@ -172,7 +174,8 @@ struct intel_super {
                struct imsm_disk disk;
                int fd;
        } *disks;
-    struct bbm_log *bbm_log;
+       struct dl *add; /* list of disks to add while mdmon active */
+       struct bbm_log *bbm_log;
 };
 
 struct extent {
@@ -183,6 +186,7 @@ struct extent {
 enum imsm_update_type {
        update_activate_spare,
        update_create_array,
+       update_add_disk,
 };
 
 struct imsm_update_activate_spare {
@@ -195,8 +199,12 @@ struct imsm_update_activate_spare {
 
 struct imsm_update_create_array {
        enum imsm_update_type type;
-       struct imsm_dev dev;
        int dev_idx;
+       struct imsm_dev dev;
+};
+
+struct imsm_update_add_disk {
+       enum imsm_update_type type;
 };
 
 static int imsm_env_devname_as_serial(void)
@@ -290,7 +298,10 @@ struct imsm_map *get_imsm_map(struct imsm_dev *dev, int second_map)
                
 }
 
-static size_t sizeof_imsm_dev(struct imsm_dev *dev)
+/* return the size of the device.
+ * migr_state increases the returned size if map[0] were to be duplicated
+ */
+static size_t sizeof_imsm_dev(struct imsm_dev *dev, int migr_state)
 {
        size_t size = sizeof(*dev) - sizeof(struct imsm_map) +
                      sizeof_imsm_map(get_imsm_map(dev, 0));
@@ -298,6 +309,8 @@ static size_t sizeof_imsm_dev(struct imsm_dev *dev)
        /* migrating means an additional map */
        if (dev->vol.migr_state)
                size += sizeof_imsm_map(get_imsm_map(dev, 1));
+       else if (migr_state)
+               size += sizeof_imsm_map(get_imsm_map(dev, 0));
 
        return size;
 }
@@ -318,7 +331,7 @@ static struct imsm_dev *__get_imsm_dev(struct imsm_super *mpb, __u8 index)
                if (i == index)
                        return _mpb + offset;
                else
-                       offset += sizeof_imsm_dev(_mpb + offset);
+                       offset += sizeof_imsm_dev(_mpb + offset, 0);
 
        return NULL;
 }
@@ -334,10 +347,24 @@ static __u32 get_imsm_disk_idx(struct imsm_map *map, int slot)
 {
        __u32 *ord_tbl = &map->disk_ord_tbl[slot];
 
-       /* top byte is 'special' */
+       /* top byte identifies disk under rebuild
+        * why not just use the USABLE bit... oh well.
+        */
        return __le32_to_cpu(*ord_tbl & ~(0xff << 24));
 }
 
+static __u32 get_imsm_ord_tbl_ent(struct imsm_dev *dev, int slot)
+{
+       struct imsm_map *map;
+
+       if (dev->vol.migr_state)
+               map = get_imsm_map(dev, 0);
+       else
+               map = get_imsm_map(dev, 1);
+
+       return map->disk_ord_tbl[slot];
+}
+
 static int get_imsm_raid_level(struct imsm_map *map)
 {
        if (map->raid_level == 1) {
@@ -439,9 +466,17 @@ static void print_imsm_dev(struct imsm_dev *dev, int index)
        printf("     Chunk Size : %u KiB\n",
                __le16_to_cpu(map->blocks_per_strip) / 2);
        printf("       Reserved : %d\n", __le32_to_cpu(dev->reserved_blocks));
-       printf("  Migrate State : %s\n", dev->vol.migr_state ? "migrating" : "idle");
+       printf("  Migrate State : %s", dev->vol.migr_state ? "migrating" : "idle");
+       if (dev->vol.migr_state)
+               printf(": %s", dev->vol.migr_type ? "rebuilding" : "initializing");
+       printf("\n");
+       printf("      Map State : %s", map_state_str[map->map_state]);
+       if (dev->vol.migr_state) {
+               struct imsm_map *map = get_imsm_map(dev, 1);
+               printf(", %s", map_state_str[map->map_state]);
+       }
+       printf("\n");
        printf("    Dirty State : %s\n", dev->vol.dirty ? "dirty" : "clean");
-       printf("      Map State : %s\n", map_state_str[map->map_state]);
 }
 
 static void print_imsm_disk(struct imsm_super *mpb, int index)
@@ -535,7 +570,13 @@ static int match_home_imsm(struct supertype *st, char *homehost)
 
 static void uuid_from_super_imsm(struct supertype *st, int uuid[4])
 {
-       printf("%s\n", __FUNCTION__);
+       /* imsm does not track uuid's so just make sure we never return
+        * the same value twice to break uuid matching in Manage_subdevs
+        * FIXME what about the use of uuid's with bitmap's?
+        */
+       static int dummy_id = 0;
+
+       uuid[0] = dummy_id++;
 }
 
 #if 0
@@ -748,10 +789,6 @@ static int compare_super_imsm(struct supertype *st, struct supertype *tst)
            sec->anchor->num_raid_devs > 0) {
                if (first->anchor->family_num != sec->anchor->family_num)
                        return 3;
-               if (first->anchor->mpb_size != sec->anchor->mpb_size)
-                       return 3;
-               if (first->anchor->check_sum != sec->anchor->check_sum)
-                       return 3;
        }
 
        return 0;
@@ -869,6 +906,7 @@ load_imsm_disk(int fd, struct intel_super *super, char *devname, int keep_fd)
                dl->fd = keep_fd ? fd : -1;
                dl->devname = devname ? strdup(devname) : NULL;
                strncpy((char *) dl->serial, (char *) serial, MAX_RAID_SERIAL_LEN);
+               dl->index = -3;
        } else if (keep_fd) {
                close(dl->fd);
                dl->fd = fd;
@@ -889,7 +927,9 @@ load_imsm_disk(int fd, struct intel_super *super, char *devname, int keep_fd)
                        /* only set index on disks that are a member of a
                         * populated contianer, i.e. one with raid_devs
                         */
-                       if (status & SPARE_DISK)
+                       if (status & FAILED_DISK)
+                               dl->index = -2;
+                       else if (status & SPARE_DISK)
                                dl->index = -1;
                        else
                                dl->index = i;
@@ -897,32 +937,30 @@ load_imsm_disk(int fd, struct intel_super *super, char *devname, int keep_fd)
                }
        }
 
-       if (i == super->anchor->num_disks && alloc) {
-               if (devname)
-                       fprintf(stderr,
-                               Name ": failed to load disk with serial \'%s\' for %s\n",
-                               dl->serial, devname);
-               free(dl);
-               return 1;
-       }
-       if (i == super->anchor->num_disks && dl->index >= 0) {
-               if (devname)
-                       fprintf(stderr,
-                               Name ": confused... disk %d with serial \'%s\' "
-                               "is not listed in the current anchor\n",
-                               dl->index, dl->serial);
-               return 1;
+       if (dl->index == -3) {
+               fprintf(stderr, Name ": device %x:%x with serial %s"
+                       " does not belong to this container\n",
+                       dl->major, dl->minor, (char *) serial);
+               return 2;
        }
 
        if (alloc)
                super->disks = dl;
-               
+
        return 0;
 }
 
 static void imsm_copy_dev(struct imsm_dev *dest, struct imsm_dev *src)
 {
-       memcpy(dest, src, sizeof_imsm_dev(src));
+       memcpy(dest, src, sizeof_imsm_dev(src, 0));
+}
+
+static void dup_map(struct imsm_dev *dev)
+{
+       struct imsm_map *dest = get_imsm_map(dev, 1);
+       struct imsm_map *src = get_imsm_map(dev, 0);
+
+       memcpy(dest, src, sizeof_imsm_map(src));
 }
 
 static int parse_raid_devices(struct intel_super *super)
@@ -934,7 +972,7 @@ static int parse_raid_devices(struct intel_super *super)
        for (i = 0; i < super->anchor->num_raid_devs; i++) {
                struct imsm_dev *dev_iter = __get_imsm_dev(super->anchor, i);
 
-               len = sizeof_imsm_dev(dev_iter);
+               len = sizeof_imsm_dev(dev_iter, 1);
                dev_new = malloc(len);
                if (!dev_new)
                        return 1;
@@ -1067,17 +1105,22 @@ static int load_imsm_mpb(int fd, struct intel_super *super, char *devname)
        return rc;
 }
 
+static void __free_imsm_disk(struct dl *d)
+{
+       if (d->fd >= 0)
+               close(d->fd);
+       if (d->devname)
+               free(d->devname);
+       free(d);
+
+}
 static void free_imsm_disks(struct intel_super *super)
 {
        while (super->disks) {
                struct dl *d = super->disks;
 
                super->disks = d->next;
-               if (d->fd >= 0)
-                       close(d->fd);
-               if (d->devname)
-                       free(d->devname);
-               free(d);
+               __free_imsm_disk(d);
        }
 }
 
@@ -1222,11 +1265,11 @@ static int load_super_imsm_all(struct supertype *st, int fd, void **sbp,
        }
 
        *sbp = super;
+       st->container_dev = fd2devnum(fd);
        if (st->ss == NULL) {
                st->ss = &super_imsm;
                st->minor_version = 0;
                st->max_devs = IMSM_MAX_DEVICES;
-               st->container_dev = fd2devnum(fd);
        }
 
        return 0;
@@ -1514,7 +1557,6 @@ static void add_to_super_imsm(struct supertype *st, mdu_disk_info_t *dk,
        dd->minor = minor(stb.st_rdev);
        dd->index = -1;
        dd->devname = devname ? strdup(devname) : NULL;
-       dd->next = super->disks;
        dd->fd = fd;
        rv = imsm_read_serial(fd, devname, dd->serial);
        if (rv) {
@@ -1534,7 +1576,14 @@ static void add_to_super_imsm(struct supertype *st, mdu_disk_info_t *dk,
                dd->disk.scsi_id = __cpu_to_le32(id);
        else
                dd->disk.scsi_id = __cpu_to_le32(0);
-       super->disks = dd;
+
+       if (st->update_tail) {
+               dd->next = super->add;
+               super->add = dd;
+       } else {
+               dd->next = super->disks;
+               super->disks = dd;
+       }
 }
 
 static int store_imsm_mpb(int fd, struct intel_super *super);
@@ -1569,7 +1618,7 @@ static int write_super_imsm_spares(struct intel_super *super, int doclose)
                        fprintf(stderr, "%s: failed for device %d:%d %s\n",
                                __func__, d->major, d->minor, strerror(errno));
                        *mpb = mpb_save;
-                       return 0;
+                       return 1;
                }
                if (doclose) {
                        close(d->fd);
@@ -1578,7 +1627,7 @@ static int write_super_imsm_spares(struct intel_super *super, int doclose)
        }
 
        *mpb = mpb_save;
-       return 1;
+       return 0;
 }
 
 static int write_super_imsm(struct intel_super *super, int doclose)
@@ -1590,6 +1639,7 @@ static int write_super_imsm(struct intel_super *super, int doclose)
        int spares = 0;
        int raid_disks = 0;
        int i;
+       __u32 mpb_size = sizeof(struct imsm_super) - sizeof(struct imsm_disk);
 
        /* 'generation' is incremented everytime the metadata is written */
        generation = __le32_to_cpu(mpb->generation_num);
@@ -1602,19 +1652,23 @@ static int write_super_imsm(struct intel_super *super, int doclose)
                else {
                        raid_disks++;
                        mpb->disk[d->index] = d->disk;
+                       mpb_size += sizeof(struct imsm_disk);
                }
        }
        if (raid_disks != mpb->num_disks) {
                fprintf(stderr, "%s: expected %d disks only found %d\n",
                        __func__, mpb->num_disks, raid_disks);
-               return 0;
+               return 1;
        }
 
        for (i = 0; i < mpb->num_raid_devs; i++) {
                struct imsm_dev *dev = __get_imsm_dev(mpb, i);
 
                imsm_copy_dev(dev, super->dev_tbl[i]);
+               mpb_size += sizeof_imsm_dev(dev, 0);
        }
+       mpb_size += __le32_to_cpu(mpb->bbm_log_size);
+       mpb->mpb_size = __cpu_to_le32(mpb_size);
 
        /* recalculate checksum */
        sum = __gen_imsm_checksum(mpb);
@@ -1627,7 +1681,7 @@ static int write_super_imsm(struct intel_super *super, int doclose)
                if (store_imsm_mpb(d->fd, super)) {
                        fprintf(stderr, "%s: failed for device %d:%d %s\n",
                                __func__, d->major, d->minor, strerror(errno));
-                       return 0;
+                       return 1;
                }
                if (doclose) {
                        close(d->fd);
@@ -1638,46 +1692,79 @@ static int write_super_imsm(struct intel_super *super, int doclose)
        if (spares)
                return write_super_imsm_spares(super, doclose);
 
-       return 1;
+       return 0;
+}
+
+static int create_array(struct supertype *st)
+{
+       size_t len;
+       struct imsm_update_create_array *u;
+       struct intel_super *super = st->sb;
+       struct imsm_dev *dev = get_imsm_dev(super, super->current_vol);
+
+       len = sizeof(*u) - sizeof(*dev) + sizeof_imsm_dev(dev, 0);
+       u = malloc(len);
+       if (!u) {
+               fprintf(stderr, "%s: failed to allocate update buffer\n",
+                       __func__);
+               return 1;
+       }
+
+       u->type = update_create_array;
+       u->dev_idx = super->current_vol;
+       imsm_copy_dev(&u->dev, dev);
+       append_metadata_update(st, u, len);
+
+       return 0;
+}
+
+static int add_disk(struct supertype *st)
+{
+       struct intel_super *super = st->sb;
+       size_t len;
+       struct imsm_update_add_disk *u;
+
+       if (!super->add)
+               return 0;
+
+       len = sizeof(*u);
+       u = malloc(len);
+       if (!u) {
+               fprintf(stderr, "%s: failed to allocate update buffer\n",
+                       __func__);
+               return 1;
+       }
+
+       u->type = update_add_disk;
+       append_metadata_update(st, u, len);
+
+       return 0;
 }
 
 static int write_init_super_imsm(struct supertype *st)
 {
        if (st->update_tail) {
-               /* queue the recently created array as a metadata update */
-               size_t len;
-               struct imsm_update_create_array *u;
+               /* queue the recently created array / added disk
+                * as a metadata update */
                struct intel_super *super = st->sb;
-               struct imsm_dev *dev;
                struct dl *d;
+               int rv;
 
-               if (super->current_vol < 0 ||
-                   !(dev = get_imsm_dev(super, super->current_vol))) {
-                       fprintf(stderr, "%s: could not determine sub-array\n",
-                               __func__);
-                       return 1;
-               }
-
-
-               len = sizeof(*u) - sizeof(*dev) + sizeof_imsm_dev(dev);
-               u = malloc(len);
-               if (!u) {
-                       fprintf(stderr, "%s: failed to allocate update buffer\n",
-                               __func__);
-                       return 1;
-               }
-
-               u->type = update_create_array;
-               u->dev_idx = super->current_vol;
-               imsm_copy_dev(&u->dev, dev);
-               append_metadata_update(st, u, len);
+               /* determine if we are creating a volume or adding a disk */
+               if (super->current_vol < 0) {
+                       /* in the add disk case we are running in mdmon
+                        * context, so don't close fd's
+                        */
+                       return add_disk(st);
+               } else
+                       rv = create_array(st);
 
                for (d = super->disks; d ; d = d->next) {
                        close(d->fd);
                        d->fd = -1;
                }
 
-               return 0;
+               return rv;
        } else
                return write_super_imsm(st->sb, 1);
 }
@@ -1968,7 +2055,6 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
                this = malloc(sizeof(*this));
                memset(this, 0, sizeof(*this));
                this->next = rest;
-               rest = this;
 
                this->array.level = get_imsm_raid_level(map);
                this->array.raid_disks = map->num_members;
@@ -1979,7 +2065,8 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
                this->array.chunk_size = __le16_to_cpu(map->blocks_per_strip) << 9;
                this->array.state = !vol->dirty;
                this->container_member = i;
-               if (map->map_state == IMSM_T_STATE_UNINITIALIZED || dev->vol.dirty)
+               if (map->map_state == IMSM_T_STATE_UNINITIALIZED ||
+                   dev->vol.dirty || dev->vol.migr_state)
                        this->resync_start = 0;
                else
                        this->resync_start = ~0ULL;
@@ -1999,32 +2086,55 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
                        struct mdinfo *info_d;
                        struct dl *d;
                        int idx;
+                       int skip;
                        __u32 s;
+                       __u32 ord;
 
+                       skip = 0;
                        idx = get_imsm_disk_idx(map, slot);
+                       ord = get_imsm_ord_tbl_ent(dev, slot); 
                        for (d = super->disks; d ; d = d->next)
                                if (d->index == idx)
                                         break;
 
                        if (d == NULL)
-                               break; /* shouldn't this be continue ?? */
+                               skip = 1;
+
+                       s = d ? __le32_to_cpu(d->disk.status) : 0;
+                       if (s & FAILED_DISK)
+                               skip = 1;
+                       if (!(s & USABLE_DISK))
+                               skip = 1;
+                       if (ord & IMSM_ORD_REBUILD)
+                               skip = 1;
+
+                       /* 
+                        * if we skip some disks the array will be assmebled degraded;
+                        * reset resync start to avoid a dirty-degraded situation
+                        *
+                        * FIXME handle dirty degraded
+                        */
+                       if (skip && !dev->vol.dirty)
+                               this->resync_start = ~0ULL;
+                       if (skip)
+                               continue;
 
                        info_d = malloc(sizeof(*info_d));
-                       if (!info_d)
-                               break; /* ditto ?? */
+                       if (!info_d) {
+                               fprintf(stderr, Name ": failed to allocate disk"
+                                       " for volume %s\n", (char *) dev->volume);
+                               free(this);
+                               this = rest;
+                               break;
+                       }
                        memset(info_d, 0, sizeof(*info_d));
                        info_d->next = this->devs;
                        this->devs = info_d;
 
-                       s = __le32_to_cpu(d->disk.status);
-
                        info_d->disk.number = d->index;
                        info_d->disk.major = d->major;
                        info_d->disk.minor = d->minor;
                        info_d->disk.raid_disk = slot;
-                       info_d->disk.state  = s & CONFIGURED_DISK ? (1 << MD_DISK_ACTIVE) : 0;
-                       info_d->disk.state |= s & FAILED_DISK ? (1 << MD_DISK_FAULTY) : 0;
-                       info_d->disk.state |= s & USABLE_DISK ? (1 << MD_DISK_SYNC) : 0;
 
                        this->array.working_disks++;
 
@@ -2034,6 +2144,7 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
                        if (d->devname)
                                strcpy(info_d->name, d->devname);
                }
+               rest = this;
        }
 
        return rest;
@@ -2063,7 +2174,8 @@ static __u8 imsm_check_degraded(struct intel_super *super, int n, int failed)
        struct imsm_map *map = get_imsm_map(dev, 0);
 
        if (!failed)
-               return map->map_state;
+               return map->map_state == IMSM_T_STATE_UNINITIALIZED ? 
+                       IMSM_T_STATE_UNINITIALIZED : IMSM_T_STATE_NORMAL;
 
        switch (get_imsm_raid_level(map)) {
        case 0:
@@ -2129,12 +2241,14 @@ static int imsm_count_failed(struct intel_super *super, struct imsm_map *map)
                disk = get_imsm_disk(super, idx);
                if (__le32_to_cpu(disk->status) & FAILED_DISK)
                        failed++;
+               else if (!(__le32_to_cpu(disk->status) & USABLE_DISK))
+                       failed++;
        }
 
        return failed;
 }
 
-static void imsm_set_array_state(struct active_array *a, int consistent)
+static int imsm_set_array_state(struct active_array *a, int consistent)
 {
        int inst = a->info.container_member;
        struct intel_super *super = a->container->sb;
@@ -2144,34 +2258,49 @@ static void imsm_set_array_state(struct active_array *a, int consistent)
        int failed;
        __u8 map_state;
 
+       failed = imsm_count_failed(super, map);
+       map_state = imsm_check_degraded(super, inst, failed);
+
+       if (consistent && !dev->vol.dirty &&
+           (dev->vol.migr_state || map_state != IMSM_T_STATE_NORMAL))
+               a->resync_start = 0ULL;
+       if (consistent == 2 && a->resync_start != ~0ULL)
+               consistent = 0;
+
        if (a->resync_start == ~0ULL) {
-               failed = imsm_count_failed(super, map);
-               map_state = imsm_check_degraded(super, inst, failed);
                /* complete recovery or initial resync */
-               if (!failed)
-                       map_state = IMSM_T_STATE_NORMAL;
                if (map->map_state != map_state) {
                        dprintf("imsm: map_state %d: %d\n",
                                inst, map_state);
                        map->map_state = map_state;
                        super->updates_pending++;
                }
-
-               /* complete resync */
-               if (!dirty && dev->vol.dirty) {
-                       dprintf("imsm: mark 'clean'\n");
-                       dev->vol.dirty = 0;
+               if (dev->vol.migr_state) {
+                       dprintf("imsm: mark resync complete\n");
+                       dev->vol.migr_state = 0;
+                       dev->vol.migr_type = 0;
                        super->updates_pending++;
-
                }
+       } else if (!dev->vol.migr_state) {
+               dprintf("imsm: mark '%s' (%llu)\n",
+                       failed ? "rebuild" : "initializing", a->resync_start);
+               /* mark that we are rebuilding */
+               map->map_state = failed ? map_state : IMSM_T_STATE_NORMAL;
+               dev->vol.migr_state = 1;
+               dev->vol.migr_type = failed ? 1 : 0;
+               dup_map(dev);
+               a->check_degraded = 1;
+               super->updates_pending++;
        }
 
-       /* mark dirty */
-       if (dirty && !dev->vol.dirty) {
-               dprintf("imsm: mark 'dirty' (%llu)\n", a->resync_start);
-               dev->vol.dirty = 1;
+       /* mark dirty / clean */
+       if (dirty != dev->vol.dirty) {
+               dprintf("imsm: mark '%s' (%llu)\n",
+                       dirty ? "dirty" : "clean", a->resync_start);
+               dev->vol.dirty = dirty;
                super->updates_pending++;
        }
+       return consistent;
 }
 
 static void imsm_set_disk(struct active_array *a, int n, int state)
@@ -2230,6 +2359,8 @@ static void imsm_set_disk(struct active_array *a, int n, int state)
 
                if (working == a->info.array.raid_disks) {
                        map->map_state = IMSM_T_STATE_NORMAL;
+                       dev->vol.migr_state = 0;
+                       dev->vol.migr_type = 0;
                        super->updates_pending++;
                }
        }
@@ -2278,6 +2409,104 @@ static void imsm_sync_metadata(struct supertype *container)
        super->updates_pending = 0;
 }
 
+static struct dl *imsm_readd(struct intel_super *super, int idx, struct active_array *a)
+{
+       struct imsm_dev *dev = get_imsm_dev(super, a->info.container_member);
+       struct imsm_map *map = get_imsm_map(dev, 0);
+       int i = get_imsm_disk_idx(map, idx);
+       struct dl *dl;
+
+       for (dl = super->disks; dl; dl = dl->next)
+               if (dl->index == i)
+                       break;
+
+       if (__le32_to_cpu(dl->disk.status) & FAILED_DISK)
+               dl = NULL;
+
+       if (dl)
+               dprintf("%s: found %x:%x\n", __func__, dl->major, dl->minor);
+
+       return dl;
+}
+
+static struct dl *imsm_add_spare(struct intel_super *super, int idx, struct active_array *a)
+{
+       struct imsm_dev *dev = get_imsm_dev(super, a->info.container_member);
+       struct imsm_map *map = get_imsm_map(dev, 0);
+       unsigned long long esize;
+       unsigned long long pos;
+       struct mdinfo *d;
+       struct extent *ex;
+       int j;
+       int found;
+       __u32 array_start;
+       __u32 status;
+       struct dl *dl;
+
+       for (dl = super->disks; dl; dl = dl->next) {
+               /* If in this array, skip */
+               for (d = a->info.devs ; d ; d = d->next)
+                       if (d->disk.major == dl->major &&
+                           d->disk.minor == dl->minor) {
+                               dprintf("%x:%x already in array\n", dl->major, dl->minor);
+                               break;
+                       }
+               if (d)
+                       continue;
+
+               /* skip marked in use or failed drives */
+               status = __le32_to_cpu(dl->disk.status);
+               if (status & FAILED_DISK || status & CONFIGURED_DISK) {
+                       dprintf("%x:%x status ( %s%s)\n",
+                       dl->major, dl->minor,
+                       status & FAILED_DISK ? "failed " : "",
+                       status & CONFIGURED_DISK ? "configured " : "");
+                       continue;
+               }
+
+               /* Does this unused device have the requisite free space?
+                * We need a->info.component_size sectors
+                */
+               ex = get_extents(super, dl);
+               if (!ex) {
+                       dprintf("cannot get extents\n");
+                       continue;
+               }
+               found = 0;
+               j = 0;
+               pos = 0;
+               array_start = __le32_to_cpu(map->pba_of_lba0);
+
+               do {
+                       /* check that we can start at pba_of_lba0 with
+                        * a->info.component_size of space
+                        */
+                       esize = ex[j].start - pos;
+                       if (array_start >= pos &&
+                           array_start + a->info.component_size < ex[j].start) {
+                               found = 1;
+                               break;
+                       }
+                       pos = ex[j].start + ex[j].size;
+                       j++;
+                           
+               } while (ex[j-1].size);
+
+               free(ex);
+               if (!found) {
+                       dprintf("%x:%x does not have %llu at %d\n",
+                               dl->major, dl->minor,
+                               a->info.component_size,
+                               __le32_to_cpu(map->pba_of_lba0));
+                       /* No room */
+                       continue;
+               } else
+                       break;
+       }
+
+       return dl;
+}
+
 static struct mdinfo *imsm_activate_spare(struct active_array *a,
                                          struct metadata_update **updates)
 {
@@ -2321,7 +2550,6 @@ static struct mdinfo *imsm_activate_spare(struct active_array *a,
                return NULL;
 
        /* For each slot, if it is not working, find a spare */
-       dl = super->disks;
        for (i = 0; i < a->info.array.raid_disks; i++) {
                for (d = a->info.devs ; d ; d = d->next)
                        if (d->disk.raid_disk == i)
@@ -2330,96 +2558,47 @@ static struct mdinfo *imsm_activate_spare(struct active_array *a,
                if (d && (d->state_fd >= 0))
                        continue;
 
-               /* OK, this device needs recovery.  Find a spare */
-               for ( ; dl ; dl = dl->next) {
-                       unsigned long long esize;
-                       unsigned long long pos;
-                       struct mdinfo *d2;
-                       struct extent *ex;
-                       int j;
-                       int found;
-                       __u32 array_start;
-
-                       /* If in this array, skip */
-                       for (d2 = a->info.devs ; d2 ; d2 = d2->next)
-                               if (d2->disk.major == dl->major &&
-                                   d2->disk.minor == dl->minor) {
-                                       dprintf("%x:%x already in array\n", dl->major, dl->minor);
-                                       break;
-                               }
-                       if (d2)
-                               continue;
-
-                       /* Does this unused device have the requisite free space?
-                        * We need a->info.component_size sectors
-                        */
-                       ex = get_extents(super, dl);
-                       if (!ex) {
-                               dprintf("cannot get extents\n");
-                               continue;
-                       }
-                       found = 0;
-                       j = 0;
-                       pos = 0;
-                       array_start = __le32_to_cpu(map->pba_of_lba0);
-
-                       do {
-                               /* check that we can start at pba_of_lba0 with
-                                * a->info.component_size of space
-                                */
-                               esize = ex[j].start - pos;
-                               if (array_start >= pos &&
-                                   array_start + a->info.component_size < ex[j].start) {
-                                       found = 1;
-                                       break;
-                               }
-                               pos = ex[j].start + ex[j].size;
-                               j++;
-                                   
-                       } while (ex[j-1].size);
-
-                       free(ex);
-                       if (!found) {
-                               dprintf("%x:%x does not have %llu at %d\n",
-                                       dl->major, dl->minor,
-                                       a->info.component_size,
-                                       __le32_to_cpu(map->pba_of_lba0));
-                               /* No room */
-                               continue;
-                       }
-
-                       /* found a usable disk with enough space */
-                       di = malloc(sizeof(*di));
-                       memset(di, 0, sizeof(*di));
-
-                       /* dl->index will be -1 in the case we are activating a
-                        * pristine spare.  imsm_process_update() will create a
-                        * new index in this case.  Once a disk is found to be
-                        * failed in all member arrays it is kicked from the
-                        * metadata
-                        */
-                       di->disk.number = dl->index;
+               /*
+                * OK, this device needs recovery.  Try to re-add the previous
+                * occupant of this slot, if this fails add a new spare
+                */
+               dl = imsm_readd(super, i, a);
+               if (!dl)
+                       dl = imsm_add_spare(super, i, a);
+               if (!dl)
+                       continue;
+               /* found a usable disk with enough space */
+               di = malloc(sizeof(*di));
+               memset(di, 0, sizeof(*di));
+
+               /* dl->index will be -1 in the case we are activating a
+                * pristine spare.  imsm_process_update() will create a
+                * new index in this case.  Once a disk is found to be
+                * failed in all member arrays it is kicked from the
+                * metadata
+                */
+               di->disk.number = dl->index;
 
-                       /* (ab)use di->devs to store a pointer to the device
-                        * we chose
-                        */
-                       di->devs = (struct mdinfo *) dl;
-
-                       di->disk.raid_disk = i;
-                       di->disk.major = dl->major;
-                       di->disk.minor = dl->minor;
-                       di->disk.state = 0;
-                       di->data_offset = array_start;
-                       di->component_size = a->info.component_size;
-                       di->container_member = inst;
-                       di->next = rv;
-                       rv = di;
-                       num_spares++;
-                       dprintf("%x:%x to be %d at %llu\n", dl->major, dl->minor,
-                               i, pos);
+               /* (ab)use di->devs to store a pointer to the device
+                * we chose
+                */
+               di->devs = (struct mdinfo *) dl;
+
+               di->disk.raid_disk = i;
+               di->disk.major = dl->major;
+               di->disk.minor = dl->minor;
+               di->disk.state = 0;
+               di->data_offset = __le32_to_cpu(map->pba_of_lba0);
+               di->component_size = a->info.component_size;
+               di->container_member = inst;
+               di->next = rv;
+               rv = di;
+               num_spares++;
+               dprintf("%x:%x to be %d at %llu\n", dl->major, dl->minor,
+                       i, di->data_offset);
 
-                       break;
-               }
+               break;
        }
 
        if (!rv)
@@ -2467,6 +2646,8 @@ static int disks_overlap(struct imsm_map *m1, struct imsm_map *m2)
        return 0;
 }
 
+static void imsm_delete(struct intel_super *super, struct dl **dlp);
+
 static void imsm_process_update(struct supertype *st,
                                struct metadata_update *update)
 {
@@ -2535,15 +2716,18 @@ static void imsm_process_update(struct supertype *st,
                 * utilized anywhere
                 */
                if (!found) {
-                       disk = get_imsm_disk(super, victim);
+                       struct dl **dlp;
+                       for (dlp = &super->disks; *dlp; )
+                               if ((*dlp)->index == victim)
+                                       break;
+                       disk = &(*dlp)->disk;
                        status = __le32_to_cpu(disk->status);
                        status &= ~(CONFIGURED_DISK | USABLE_DISK);
                        disk->status = __cpu_to_le32(status);
-                       /* at this point the disk can be removed from the
-                        * metadata, however we need to guarantee that we do
-                        * not race with any manager thread routine that relies
-                        * on dl->index or map->disk_ord_tbl
-                        */ 
+                       /* We know that 'manager' isn't touching anything,
+                        * so it is safe to:
+                        */
+                       imsm_delete(super, dlp);
                }
                break;
        }
@@ -2574,8 +2758,8 @@ static void imsm_process_update(struct supertype *st,
 
                /* check update is next in sequence */
                if (u->dev_idx != mpb->num_raid_devs) {
-                       dprintf("%s: can not create arrays out of sequence\n",
-                               __func__);
+                       dprintf("%s: can not create array %d expected index %d\n",
+                               __func__, u->dev_idx, mpb->num_raid_devs);
                        return;
                }
 
@@ -2635,6 +2819,36 @@ static void imsm_process_update(struct supertype *st,
                }
                break;
        }
+       case update_add_disk:
+
+               /* we may be able to repair some arrays if disks are
+                * being added */
+               if (super->add) {
+                       struct active_array *a;
+                       for (a = st->arrays; a; a = a->next)
+                               a->check_degraded = 1;
+               }
+               /* check if we can add / replace some disks in the
+                * metadata */
+               while (super->add) {
+                       struct dl **dlp, *dl, *al;
+                       al = super->add;
+                       super->add = al->next;
+                       for (dlp = &super->disks; *dlp ; ) {
+                               if (memcmp(al->serial, (*dlp)->serial,
+                                          MAX_RAID_SERIAL_LEN) == 0) {
+                                       dl = *dlp;
+                                       *dlp = (*dlp)->next;
+                                       __free_imsm_disk(dl);
+                                       break;
+                               } else
+                                       dlp = &(*dlp)->next;
+                       }
+                       al->next = super->disks;
+                       super->disks = al;
+               }
+
+               break;
        }
 }
 
@@ -2659,7 +2873,7 @@ static void imsm_prepare_update(struct supertype *st,
        switch (type) {
        case update_create_array: {
                struct imsm_update_create_array *u = (void *) update->buf;
-               size_t len = sizeof_imsm_dev(&u->dev);
+               size_t len = sizeof_imsm_dev(&u->dev, 1);
 
                update->space = malloc(len);
                break;
@@ -2671,6 +2885,42 @@ static void imsm_prepare_update(struct supertype *st,
        return;
 }
 
+/* must be called while manager is quiesced */
+static void imsm_delete(struct intel_super *super, struct dl **dlp)
+{
+       struct imsm_super *mpb = super->anchor;
+       struct dl *dl = *dlp;
+       struct dl *iter;
+       struct imsm_dev *dev;
+       struct imsm_map *map;
+       int i, j;
+
+       dprintf("%s: deleting device %x:%x from imsm_super\n",
+               __func__, dl->major, dl->minor);
+
+       /* shift all indexes down one */
+       for (iter = super->disks; iter; iter = iter->next)
+               if (iter->index > dl->index)
+                       iter->index--;
+
+       for (i = 0; i < mpb->num_raid_devs; i++) {
+               dev = get_imsm_dev(super, i);
+               map = get_imsm_map(dev, 0);
+
+               for (j = 0; j < map->num_members; j++) {
+                       int idx = get_imsm_disk_idx(map, j);
+
+                       if (idx > dl->index)
+                               map->disk_ord_tbl[j] = __cpu_to_le32(idx - 1);
+               }
+       }
+
+       mpb->num_disks--;
+       super->updates_pending++;
+       *dlp = (*dlp)->next;
+       __free_imsm_disk(dl);
+}
+
 struct superswitch super_imsm = {
 #ifndef        MDASSEMBLE
        .examine_super  = examine_super_imsm,