releases/5.0.19/dm-cache-metadata-fix-loading-discard-bitset.patch

   1 From e28adc3bf34e434b30e8d063df4823ba0f3e0529 Mon Sep 17 00:00:00 2001
   2 From: Nikos Tsironis <ntsironis@arrikto.com>
   3 Date: Wed, 17 Apr 2019 17:19:18 +0300
   4 Subject: dm cache metadata: Fix loading discard bitset
   5
   6 From: Nikos Tsironis <ntsironis@arrikto.com>
   7
   8 commit e28adc3bf34e434b30e8d063df4823ba0f3e0529 upstream.
   9
  10 Add missing dm_bitset_cursor_next() to properly advance the bitset
  11 cursor.
  12
  13 Otherwise, the discarded state of all blocks is set according to the
  14 discarded state of the first block.
  15
  16 Fixes: ae4a46a1f6 ("dm cache metadata: use bitset cursor api to load discard bitset")
  17 Cc: stable@vger.kernel.org
  18 Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
  19 Signed-off-by: Mike Snitzer <snitzer@redhat.com>
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21
  22 ---
  23  drivers/md/dm-cache-metadata.c |    9 ++++++++-
  24  1 file changed, 8 insertions(+), 1 deletion(-)
  25
  26 --- a/drivers/md/dm-cache-metadata.c
  27 +++ b/drivers/md/dm-cache-metadata.c
  28 @@ -1167,11 +1167,18 @@ static int __load_discards(struct dm_cac
  29                 if (r)
  30                         return r;
  31
  32 -               for (b = 0; b < from_dblock(cmd->discard_nr_blocks); b++) {
  33 +               for (b = 0; ; b++) {
  34                         r = fn(context, cmd->discard_block_size, to_dblock(b),
  35                                dm_bitset_cursor_get_value(&c));
  36                         if (r)
  37                                 break;
  38 +
  39 +                       if (b >= (from_dblock(cmd->discard_nr_blocks) - 1))
  40 +                               break;
  41 +
  42 +                       r = dm_bitset_cursor_next(&c);
  43 +                       if (r)
  44 +                               break;
  45                 }
  46
  47                 dm_bitset_cursor_end(&c);