MFC r305326: MFV r303079:

MFC r305326: MFV r303079:
7147 ztest: ztest_ddt_repair fails with ztest_pattern_match assertion

illumos/illumos-gate@aab80726335c76a7cae32c7300890248d73a51e3
https://github.com/illumos/illumos-gate/commit/aab80726335c76a7cae32c7300890248d
73a51e3

https://www.illumos.org/issues/7147
  Here's the dbuf we're currently reading:
       966f200::dbuf
  addr object lvl blkid holds os
  966f200 4 0 0 1 ztest/ds_3
       966f200::print dmu_buf_t db_data
  db_data = 0x9ae0400
       0x9ae0400/10J
  0x9ae0400: c1c7ced932020d c1c7ced932020d c1c7ced932020d c1c7ced932020d
  c1c7ced932020d c1c7ced932020d c1c7ced932020d c1c7ced932020d
  c1c7ced932020d c1c7ced932020d
  The pattern we're expecting is actually this: a34ae10b5f2db2. If we attempt to
  read the block on disk we find that it has matches what ztest_ddt_repair()
  would have written:
       ~c1c7ced932020d=J
  ff3e383126cdfdf2
       966f200::print dmu_buf_impl_t db_blkptr | ::blkptr
  DVA0=<0:71d3c00:800>
  [L0 UINT64_OTHER] SHA256 OFF LE contiguous dedup single
  size=400L/400P birth=55L/55P fill=1
  cksum=18486450d3ce8c6d:75a72f4bbf117b0f:2d3a226314eb5650:2eb0fd68648b1af0
     1. zdb -U /rpool/tmp/zpool.cache -R ztest 0:71d3c00:800 | head
        Found vdev type: mirror
  0:71d3c00:800
  0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef
  000000: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.
  000010: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.
  000020: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.
  000030: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.
  000040: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.
  000050: ff3e383126cdfdf2 ff3e383126cdfdf2 ...&18>....&18>.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: George Wilson <george.wilson@delphix.com>

git-svn-id: svn://svn.freebsd.org/base/stable/10@307272 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f