tests/qemu-iotests/044

   1 #!/usr/bin/env python
   2 #
   3 # Tests growing a large refcount table.
   4 #
   5 # Copyright (C) 2012 Red Hat, Inc.
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 #
  20
  21 import time
  22 import os
  23 import qcow2
  24 from qcow2 import QcowHeader
  25 import iotests
  26 from iotests import qemu_img, qemu_img_verbose, qemu_io
  27 import struct
  28 import subprocess
  29
  30 test_img = os.path.join(iotests.test_dir, 'test.img')
  31
  32 class TestRefcountTableGrowth(iotests.QMPTestCase):
  33     '''Abstract base class for image mirroring test cases'''
  34
  35     def preallocate(self, name):
  36         fd = open(name, "r+b")
  37         try:
  38             off_reftable = 512
  39             off_refblock = off_reftable + (512 * 512)
  40             off_l1       = off_refblock + (512 * 512 * 64)
  41             off_l2       = off_l1 + (512 * 512 * 4 * 8)
  42             off_data     = off_l2 + (512 * 512 * 4 * 512)
  43
  44             # Write a new header
  45             h = QcowHeader(fd)
  46             h.refcount_table_offset = off_reftable
  47             h.refcount_table_clusters = 512
  48             h.l1_table_offset = off_l1
  49             h.l1_size = 512 * 512 * 4
  50             h.update(fd)
  51
  52             # Write a refcount table
  53             fd.seek(off_reftable)
  54
  55             for i in xrange(0, h.refcount_table_clusters):
  56                 sector = ''.join(struct.pack('>Q',
  57                     off_refblock + i * 64 * 512 + j * 512)
  58                     for j in xrange(0, 64))
  59                 fd.write(sector)
  60
  61             # Write the refcount blocks
  62             assert(fd.tell() == off_refblock)
  63             sector = ''.join(struct.pack('>H', 1) for j in xrange(0, 64 * 256))
  64             for block in xrange(0, h.refcount_table_clusters):
  65                 fd.write(sector)
  66
  67             # Write the L1 table
  68             assert(fd.tell() == off_l1)
  69             assert(off_l2 + 512 * h.l1_size == off_data)
  70             table = ''.join(struct.pack('>Q', (1 << 63) | off_l2 + 512 * j)
  71                 for j in xrange(0, h.l1_size))
  72             fd.write(table)
  73
  74             # Write the L2 tables
  75             assert(fd.tell() == off_l2)
  76             img_file_size = h.refcount_table_clusters * 64 * 256 * 512
  77             remaining = img_file_size - off_data
  78
  79             off = off_data
  80             while remaining > 1024 * 512:
  81                 pytable = list((1 << 63) | off + 512 * j
  82                     for j in xrange(0, 1024))
  83                 table = struct.pack('>1024Q', *pytable)
  84                 fd.write(table)
  85                 remaining = remaining - 1024 * 512
  86                 off = off + 1024 * 512
  87
  88             table = ''.join(struct.pack('>Q', (1 << 63) | off + 512 * j)
  89                 for j in xrange(0, remaining / 512))
  90             fd.write(table)
  91
  92
  93             # Data
  94             fd.truncate(img_file_size)
  95
  96
  97         finally:
  98             fd.close()
  99
 100
 101     def setUp(self):
 102         qemu_img('create', '-f', iotests.imgfmt, '-o', 'cluster_size=512', test_img, '16G')
 103         self.preallocate(test_img)
 104         pass
 105
 106
 107     def tearDown(self):
 108         os.remove(test_img)
 109         pass
 110
 111     def test_grow_refcount_table(self):
 112         qemu_io('-c', 'write 3800M 1M', test_img)
 113         qemu_img_verbose('check' , test_img)
 114         pass
 115
 116 if __name__ == '__main__':
 117     iotests.main(supported_fmts=['qcow2'])