ceph/qa/rbd/krbd_parent_overlap.t

   1
   2 For reads, only the object extent needs to be reverse mapped:
   3
   4   $ rbd create --size 5M img
   5   $ DEV=$(sudo rbd map img)
   6   $ xfs_io -c 'pwrite 0 5M' $DEV >/dev/null
   7   $ sudo rbd unmap $DEV
   8   $ rbd snap create img@snap
   9   $ rbd snap protect img@snap
  10   $ rbd clone img@snap cloneimg
  11   $ rbd resize --no-progress --size 12M cloneimg
  12   $ DEV=$(sudo rbd map cloneimg)
  13   $ hexdump $DEV
  14   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  15   *
  16   0500000 0000 0000 0000 0000 0000 0000 0000 0000
  17   *
  18   0c00000
  19   $ dd if=$DEV iflag=direct bs=4M status=none | hexdump
  20   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  21   *
  22   0500000 0000 0000 0000 0000 0000 0000 0000 0000
  23   *
  24   0c00000
  25   $ sudo rbd unmap $DEV
  26   $ rbd rm --no-progress cloneimg
  27   $ rbd snap unprotect img@snap
  28   $ rbd snap rm --no-progress img@snap
  29   $ rbd rm --no-progress img
  30
  31 For writes, the entire object needs to be reverse mapped:
  32
  33   $ rbd create --size 2M img
  34   $ DEV=$(sudo rbd map img)
  35   $ xfs_io -c 'pwrite 0 1M' $DEV >/dev/null
  36   $ sudo rbd unmap $DEV
  37   $ rbd snap create img@snap
  38   $ rbd snap protect img@snap
  39   $ rbd clone img@snap cloneimg
  40   $ rbd resize --no-progress --size 8M cloneimg
  41   $ DEV=$(sudo rbd map cloneimg)
  42   $ xfs_io -c 'pwrite -S 0xef 3M 1M' $DEV >/dev/null
  43   $ hexdump $DEV
  44   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  45   *
  46   0100000 0000 0000 0000 0000 0000 0000 0000 0000
  47   *
  48   0300000 efef efef efef efef efef efef efef efef
  49   *
  50   0400000 0000 0000 0000 0000 0000 0000 0000 0000
  51   *
  52   0800000
  53   $ sudo rbd unmap $DEV
  54   $ DEV=$(sudo rbd map cloneimg)
  55   $ hexdump $DEV
  56   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  57   *
  58   0100000 0000 0000 0000 0000 0000 0000 0000 0000
  59   *
  60   0300000 efef efef efef efef efef efef efef efef
  61   *
  62   0400000 0000 0000 0000 0000 0000 0000 0000 0000
  63   *
  64   0800000
  65   $ sudo rbd unmap $DEV
  66   $ rbd rm --no-progress cloneimg
  67   $ rbd snap unprotect img@snap
  68   $ rbd snap rm --no-progress img@snap
  69   $ rbd rm --no-progress img