src/patches/suse-2.6.27.31/patches.fixes/md-raid1-chunksize

   1 From: NeilBrown <neilb@suse.de>
   2 Subject: Don't fail to start a RAID1 with a small chunksize
   3 Patch-mainline: no
   4 References: 459557
   5
   6 For a RAID1 array, chunksize is almost meaningless (it is used to
   7 round down the device size to a multiple of chunksize, but that is
   8 largely of historical interest).
   9 However it is possible to set the chunksize, and it is possible to
  10 set it to be less than PAGE_SIZE.  This currently causes the
  11 array to fail to start.  However there is no good reason for that.
  12 And YaST seems to create RAID1 arrays with a 4K chunks which breaks
  13 on PPC-64 machines with 64K pages.
  14
  15 So ignore the "chunk_size < PAGE_SIZE" check on RAID1 like we do
  16 for RAID0
  17
  18 Signed-off-by: Neil Brown <neilb@suse.de>
  19
  20 ---
  21  drivers/md/md.c |    6 +++---
  22  1 file changed, 3 insertions(+), 3 deletions(-)
  23
  24 --- a/drivers/md/md.c
  25 +++ b/drivers/md/md.c
  26 @@ -3587,13 +3587,13 @@ static int do_md_run(mddev_t * mddev)
  27                         return -EINVAL;
  28                 }
  29                 if (chunk_size < PAGE_SIZE) {
  30 -                       if (mddev->level) {
  31 +                       if (mddev->level != 0 && mddev->level != 1) {
  32                         printk(KERN_ERR "too small chunk_size: %d < %ld\n",
  33                                 chunk_size, PAGE_SIZE);
  34                         return -EINVAL;
  35                         } else {
  36 -                               printk(KERN_ERR "too small chunk_size: %d < %ld, but continuing anyway on raid0. Good luck!\n",
  37 -                                       chunk_size, PAGE_SIZE);
  38 +                               printk(KERN_ERR "too small chunk_size: %d < %ld, but continuing anyway on raid%d. Good luck!\n",
  39 +                                       chunk_size, PAGE_SIZE, mddev->level);
  40                         }
  41                 }
  42