src/patches/suse-2.6.27.25/patches.suse/dm-emulate-blkrrpart-ioctl

   1 From: Hannes Reinecke <hare@suse.de>
   2 Subject: Emulate BLKRRPART on device-mapper
   3
   4 Partitions on device-mapper devices are managed by kpartx (if at
   5 all). So if we were just to send out a 'change' event if someone
   6 called BLKRRPART on these devices, kpartx will be triggered via udev
   7 and can manage the partitions accordingly.
   8
   9 Signed-off-by: Hannes Reinecke <hare@suse.de>
  10
  11 ---
  12  drivers/md/dm.c |   22 ++++++++++++++--------
  13  1 file changed, 14 insertions(+), 8 deletions(-)
  14
  15 --- a/drivers/md/dm.c
  16 +++ b/drivers/md/dm.c
  17 @@ -333,19 +333,25 @@ static int dm_blk_ioctl(struct inode *in
  18         if (!map || !dm_table_get_size(map))
  19                 goto out;
  20
  21 -       /* We only support devices that have a single target */
  22 -       if (dm_table_get_num_targets(map) != 1)
  23 -               goto out;
  24 -
  25 -       tgt = dm_table_get_target(map, 0);
  26 -
  27         if (dm_suspended(md)) {
  28                 r = -EAGAIN;
  29                 goto out;
  30         }
  31
  32 -       if (tgt->type->ioctl)
  33 -               r = tgt->type->ioctl(tgt, inode, file, cmd, arg);
  34 +       if (cmd == BLKRRPART) {
  35 +               /* Emulate Re-read partitions table */
  36 +               kobject_uevent(&md->disk->dev.kobj, KOBJ_CHANGE);
  37 +               r = 0;
  38 +       } else {
  39 +               /* We only support devices that have a single target */
  40 +               if (dm_table_get_num_targets(map) != 1)
  41 +                       goto out;
  42 +
  43 +               tgt = dm_table_get_target(map, 0);
  44 +
  45 +               if (tgt->type->ioctl)
  46 +                       r = tgt->type->ioctl(tgt, inode, file, cmd, arg);
  47 +       }
  48
  49  out:
  50         dm_table_put(map);