ceph/qa/workunits/fs/misc/direct_io.py

   1 #!/usr/bin/python3
   2
   3 import json
   4 import mmap
   5 import os
   6 import subprocess
   7
   8
   9 def get_data_pool():
  10     cmd = ['ceph', 'fs', 'ls', '--format=json-pretty']
  11     proc = subprocess.Popen(cmd, stdout=subprocess.PIPE)
  12     out = proc.communicate()[0]
  13     return json.loads(out)[0]['data_pools'][0]
  14
  15
  16 def main():
  17     fd = os.open("testfile", os.O_RDWR | os.O_CREAT | os.O_TRUNC | os.O_DIRECT, 0o644)
  18
  19     ino = os.fstat(fd).st_ino
  20     obj_name = "{ino:x}.00000000".format(ino=ino)
  21     pool_name = get_data_pool()
  22
  23     buf = mmap.mmap(-1, 1)
  24     buf.write(b'1')
  25     os.write(fd, buf)
  26
  27     proc = subprocess.Popen(['rados', '-p', pool_name, 'get', obj_name, 'tmpfile'])
  28     proc.wait()
  29
  30     with open('tmpfile', 'rb') as tmpf:
  31         out = tmpf.read(1)
  32         if out != b'1':
  33             raise RuntimeError("data were not written to object store directly")
  34
  35     with open('tmpfile', 'wb') as tmpf:
  36         tmpf.write(b'2')
  37
  38     proc = subprocess.Popen(['rados', '-p', pool_name, 'put', obj_name, 'tmpfile'])
  39     proc.wait()
  40
  41     os.lseek(fd, 0, os.SEEK_SET)
  42     out = os.read(fd, 1)
  43     if out != b'2':
  44         raise RuntimeError("data were not directly read from object store")
  45
  46     os.close(fd)
  47     print('ok')
  48
  49
  50 main()