debian/patches/bitmap-mirror/0002-drive-mirror-add-support-for-conditional-and-always-.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: John Snow <jsnow@redhat.com>
   3 Date: Mon, 6 Apr 2020 12:17:04 +0200
   4 Subject: [PATCH] drive-mirror: add support for conditional and always bitmap
   5  sync modes
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 Teach mirror two new tricks for using bitmaps:
  11
  12 Always: no matter what, we synchronize the copy_bitmap back to the
  13 sync_bitmap. In effect, this allows us resume a failed mirror at a later
  14 date.
  15
  16 Conditional: On success only, we sync the bitmap. This is akin to
  17 incremental backup modes; we can use this bitmap to later refresh a
  18 successfully created mirror.
  19
  20 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  21 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
  22 ---
  23  block/mirror.c | 24 ++++++++++++++++++------
  24  1 file changed, 18 insertions(+), 6 deletions(-)
  25
  26 diff --git a/block/mirror.c b/block/mirror.c
  27 index 9099c75992..e2ff42067b 100644
  28 --- a/block/mirror.c
  29 +++ b/block/mirror.c
  30 @@ -680,8 +680,6 @@ static int mirror_exit_common(Job *job)
  31          bdrv_unfreeze_backing_chain(mirror_top_bs, target_bs);
  32      }
  33
  34 -    bdrv_release_dirty_bitmap(s->dirty_bitmap);
  35 -
  36      /* Make sure that the source BDS doesn't go away during bdrv_replace_node,
  37       * before we can call bdrv_drained_end */
  38      bdrv_ref(src);
  39 @@ -782,6 +780,18 @@ static int mirror_exit_common(Job *job)
  40      block_job_remove_all_bdrv(bjob);
  41      bdrv_replace_node(mirror_top_bs, mirror_top_bs->backing->bs, &error_abort);
  42
  43 +    if (s->sync_bitmap) {
  44 +        if (s->bitmap_mode == BITMAP_SYNC_MODE_ALWAYS ||
  45 +            (s->bitmap_mode == BITMAP_SYNC_MODE_ON_SUCCESS &&
  46 +             job->ret == 0 && ret == 0)) {
  47 +            /* Success; synchronize copy back to sync. */
  48 +            bdrv_clear_dirty_bitmap(s->sync_bitmap, NULL);
  49 +            bdrv_merge_dirty_bitmap(s->sync_bitmap, s->dirty_bitmap,
  50 +                                    NULL, &error_abort);
  51 +        }
  52 +    }
  53 +    bdrv_release_dirty_bitmap(s->dirty_bitmap);
  54 +
  55      bs_opaque->job = NULL;
  56
  57      bdrv_drained_end(src);
  58 @@ -1688,10 +1698,6 @@ static BlockJob *mirror_start_job(
  59                         " sync mode",
  60                         MirrorSyncMode_str(sync_mode));
  61              return NULL;
  62 -        } else if (bitmap_mode != BITMAP_SYNC_MODE_NEVER) {
  63 -            error_setg(errp,
  64 -                       "Bitmap Sync Mode '%s' is not supported by Mirror",
  65 -                       BitmapSyncMode_str(bitmap_mode));
  66          }
  67      } else if (bitmap) {
  68          error_setg(errp,
  69 @@ -1708,6 +1714,12 @@ static BlockJob *mirror_start_job(
  70              return NULL;
  71          }
  72          granularity = bdrv_dirty_bitmap_granularity(bitmap);
  73 +
  74 +        if (bitmap_mode != BITMAP_SYNC_MODE_NEVER) {
  75 +            if (bdrv_dirty_bitmap_check(bitmap, BDRV_BITMAP_DEFAULT, errp)) {
  76 +                return NULL;
  77 +            }
  78 +        }
  79      } else if (granularity == 0) {
  80          granularity = bdrv_get_default_bitmap_granularity(target);
  81      }