kernel-patch-2.6.25

   1 Status: ok
   2
   3 Support adding a spare to a live md array with external metadata.
   4
   5 i.e. extend the 'md/dev-XXX/slot' attribute so that you can
   6 tell a device to fill an vacant slot in an and md array.
   7
   8
   9 Signed-off-by: Neil Brown <neilb@suse.de>
  10
  11 ### Diffstat output
  12  ./drivers/md/md.c        |   44 ++++++++++++++++++++++++++++++++++++++++----
  13  ./drivers/md/multipath.c |    7 ++++++-
  14  ./drivers/md/raid1.c     |    7 ++++++-
  15  ./drivers/md/raid10.c    |   10 ++++++++--
  16  ./drivers/md/raid5.c     |   10 ++++++++--
  17  5 files changed, 68 insertions(+), 10 deletions(-)
  18
  19 diff .prev/drivers/md/md.c ./drivers/md/md.c
  20 --- .prev/drivers/md/md.c       2008-06-05 09:19:56.000000000 +1000
  21 +++ ./drivers/md/md.c   2008-06-10 10:41:21.000000000 +1000
  22 @@ -1932,7 +1932,7 @@ slot_store(mdk_rdev_t *rdev, const char
  23                 slot = -1;
  24         else if (e==buf || (*e && *e!= '\n'))
  25                 return -EINVAL;
  26 -       if (rdev->mddev->pers) {
  27 +       if (rdev->mddev->pers && slot == -1) {
  28                 /* Setting 'slot' on an active array requires also
  29                  * updating the 'rd%d' link, and communicating
  30                  * with the personality with ->hot_*_disk.
  31 @@ -1940,8 +1940,6 @@ slot_store(mdk_rdev_t *rdev, const char
  32                  * failed/spare devices.  This normally happens automatically,
  33                  * but not when the metadata is externally managed.
  34                  */
  35 -               if (slot != -1)
  36 -                       return -EBUSY;
  37                 if (rdev->raid_disk == -1)
  38                         return -EEXIST;
  39                 /* personality does all needed checks */
  40 @@ -1955,6 +1953,44 @@ slot_store(mdk_rdev_t *rdev, const char
  41                 sysfs_remove_link(&rdev->mddev->kobj, nm);
  42                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
  43                 md_wakeup_thread(rdev->mddev->thread);
  44 +       } else if (rdev->mddev->pers) {
  45 +               mdk_rdev_t *rdev2;
  46 +               struct list_head *tmp;
  47 +               /* Activating a spare .. or possibly reactivating
  48 +                * if we every get bitmaps working here.
  49 +                */
  50 +
  51 +               if (rdev->raid_disk != -1)
  52 +                       return -EBUSY;
  53 +
  54 +               if (rdev->mddev->pers->hot_add_disk == NULL)
  55 +                       return -EINVAL;
  56 +
  57 +               rdev_for_each(rdev2, tmp, rdev->mddev)
  58 +                       if (rdev2->raid_disk == slot)
  59 +                               return -EEXIST;
  60 +
  61 +               rdev->raid_disk = slot;
  62 +               if (test_bit(In_sync, &rdev->flags))
  63 +                       rdev->saved_raid_disk = slot;
  64 +               else
  65 +                       rdev->saved_raid_disk = -1;
  66 +               err = rdev->mddev->pers->
  67 +                       hot_add_disk(rdev->mddev, rdev);
  68 +               if (err != 1) {
  69 +                       rdev->raid_disk = -1;
  70 +                       if (err == 0)
  71 +                               return -EEXIST;
  72 +                       return err;
  73 +               }
  74 +               sprintf(nm, "rd%d", rdev->raid_disk);
  75 +               if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm))
  76 +                       printk(KERN_WARNING
  77 +                              "md: cannot register "
  78 +                              "%s for %s\n",
  79 +                              nm, mdname(rdev->mddev));
  80 +
  81 +               /* don't wakeup anyone, leave that to userspace. */
  82         } else {
  83                 if (slot >= rdev->mddev->raid_disks)
  84                         return -ENOSPC;
  85 @@ -4205,7 +4241,7 @@ static int add_new_disk(mddev_t * mddev,
  86                         super_types[mddev->major_version].
  87                                 validate_super(mddev, rdev);
  88                         err = mddev->pers->hot_add_disk(mddev, rdev);
  89 -                       if (err)
  90 +                       if (err < 0)
  91                                 unbind_rdev_from_array(rdev);
  92                 }
  93                 if (err)
  94
  95 diff .prev/drivers/md/multipath.c ./drivers/md/multipath.c
  96 --- .prev/drivers/md/multipath.c        2008-05-30 14:49:31.000000000 +1000
  97 +++ ./drivers/md/multipath.c    2008-06-10 10:35:03.000000000 +1000
  98 @@ -284,10 +284,15 @@ static int multipath_add_disk(mddev_t *m
  99         int found = 0;
 100         int path;
 101         struct multipath_info *p;
 102 +       int first = 0;
 103 +       int last = mddev->raid_disks - 1;
 104 +
 105 +       if (rdev->raid_disk >= 0)
 106 +               first = last = rdev->raid_disk;
 107
 108         print_multipath_conf(conf);
 109
 110 -       for (path=0; path<mddev->raid_disks; path++)
 111 +       for (path = first; path <= last; path++)
 112                 if ((p=conf->multipaths+path)->rdev == NULL) {
 113                         q = rdev->bdev->bd_disk->queue;
 114                         blk_queue_stack_limits(mddev->queue, q);
 115
 116 diff .prev/drivers/md/raid10.c ./drivers/md/raid10.c
 117 --- .prev/drivers/md/raid10.c   2008-05-30 14:49:31.000000000 +1000
 118 +++ ./drivers/md/raid10.c       2008-06-10 10:28:53.000000000 +1000
 119 @@ -1116,6 +1116,8 @@ static int raid10_add_disk(mddev_t *mdde
 120         int found = 0;
 121         int mirror;
 122         mirror_info_t *p;
 123 +       int first = 0;
 124 +       int last = mddev->raid_disks - 1;
 125
 126         if (mddev->recovery_cp < MaxSector)
 127                 /* only hot-add to in-sync arrays, as recovery is
 128 @@ -1125,12 +1127,16 @@ static int raid10_add_disk(mddev_t *mdde
 129         if (!enough(conf))
 130                 return 0;
 131
 132 +       if (rdev->raid_disk)
 133 +               first = last = rdev->raid_disk;
 134 +
 135         if (rdev->saved_raid_disk >= 0 &&
 136 +           rdev->saved_raid_disk >= first &&
 137             conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
 138                 mirror = rdev->saved_raid_disk;
 139         else
 140 -               mirror = 0;
 141 -       for ( ; mirror < mddev->raid_disks; mirror++)
 142 +               mirror = first;
 143 +       for ( ; mirror <= last ; mirror++)
 144                 if ( !(p=conf->mirrors+mirror)->rdev) {
 145
 146                         blk_queue_stack_limits(mddev->queue,
 147
 148 diff .prev/drivers/md/raid1.c ./drivers/md/raid1.c
 149 --- .prev/drivers/md/raid1.c    2008-05-30 14:49:31.000000000 +1000
 150 +++ ./drivers/md/raid1.c        2008-06-10 10:41:00.000000000 +1000
 151 @@ -1103,8 +1103,13 @@ static int raid1_add_disk(mddev_t *mddev
 152         int found = 0;
 153         int mirror = 0;
 154         mirror_info_t *p;
 155 +       int first = 0;
 156 +       int last = mddev->raid_disks - 1;
 157
 158 -       for (mirror=0; mirror < mddev->raid_disks; mirror++)
 159 +       if (rdev->raid_disk >= 0)
 160 +               first = last = rdev->raid_disk;
 161 +
 162 +       for (mirror = first; mirror <= last; mirror++)
 163                 if ( !(p=conf->mirrors+mirror)->rdev) {
 164
 165                         blk_queue_stack_limits(mddev->queue,
 166
 167 diff .prev/drivers/md/raid5.c ./drivers/md/raid5.c
 168 --- .prev/drivers/md/raid5.c    2008-05-30 14:49:35.000000000 +1000
 169 +++ ./drivers/md/raid5.c        2008-06-10 10:27:51.000000000 +1000
 170 @@ -4399,21 +4399,27 @@ static int raid5_add_disk(mddev_t *mddev
 171         int found = 0;
 172         int disk;
 173         struct disk_info *p;
 174 +       int first = 0;
 175 +       int last = conf->raid_disks - 1;
 176
 177         if (mddev->degraded > conf->max_degraded)
 178                 /* no point adding a device */
 179                 return 0;
 180
 181 +       if (rdev->raid_disk >= 0)
 182 +               first = last = rdev->raid_disk;
 183 +
 184         /*
 185          * find the disk ... but prefer rdev->saved_raid_disk
 186          * if possible.
 187          */
 188         if (rdev->saved_raid_disk >= 0 &&
 189 +           rdev->saved_raid_disk >= first &&
 190             conf->disks[rdev->saved_raid_disk].rdev == NULL)
 191                 disk = rdev->saved_raid_disk;
 192         else
 193 -               disk = 0;
 194 -       for ( ; disk < conf->raid_disks; disk++)
 195 +               disk = first;
 196 +       for ( ; disk <= last ; disk++)
 197                 if ((p=conf->disks + disk)->rdev == NULL) {
 198                         clear_bit(In_sync, &rdev->flags);
 199                         rdev->raid_disk = disk;