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 20M img
   5   $ DEV=$(sudo rbd map img)
   6   $ xfs_io -c 'pwrite 0 20M' $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 5M --allow-shrink cloneimg
  12   $ rbd resize --no-progress --size 20M cloneimg
  13   $ DEV=$(sudo rbd map cloneimg)
  14   $ hexdump $DEV
  15   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  16   *
  17   0500000 0000 0000 0000 0000 0000 0000 0000 0000
  18   *
  19   1400000
  20   $ sudo rbd unmap $DEV
  21   $ rbd rm --no-progress cloneimg
  22   $ rbd snap unprotect img@snap
  23   $ rbd snap rm --no-progress img@snap
  24   $ rbd rm --no-progress img
  25
  26 For writes, the entire object needs to be reverse mapped:
  27
  28   $ rbd create --size 2M img
  29   $ DEV=$(sudo rbd map img)
  30   $ xfs_io -c 'pwrite 0 1M' $DEV >/dev/null
  31   $ sudo rbd unmap $DEV
  32   $ rbd snap create img@snap
  33   $ rbd snap protect img@snap
  34   $ rbd clone img@snap cloneimg
  35   $ rbd resize --no-progress --size 8M cloneimg
  36   $ DEV=$(sudo rbd map cloneimg)
  37   $ xfs_io -c 'pwrite -S 0xef 3M 1M' $DEV >/dev/null
  38   $ hexdump $DEV
  39   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  40   *
  41   0100000 0000 0000 0000 0000 0000 0000 0000 0000
  42   *
  43   0300000 efef efef efef efef efef efef efef efef
  44   *
  45   0400000 0000 0000 0000 0000 0000 0000 0000 0000
  46   *
  47   0800000
  48   $ sudo rbd unmap $DEV
  49   $ DEV=$(sudo rbd map cloneimg)
  50   $ hexdump $DEV
  51   0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
  52   *
  53   0100000 0000 0000 0000 0000 0000 0000 0000 0000
  54   *
  55   0300000 efef efef efef efef efef efef efef efef
  56   *
  57   0400000 0000 0000 0000 0000 0000 0000 0000 0000
  58   *
  59   0800000
  60   $ sudo rbd unmap $DEV
  61   $ rbd rm --no-progress cloneimg
  62   $ rbd snap unprotect img@snap
  63   $ rbd snap rm --no-progress img@snap
  64   $ rbd rm --no-progress img