1#!/usr/bin/python3 

2# 

3# Copyright (C) Citrix Systems Inc. 

4# 

5# This program is free software; you can redistribute it and/or modify 

6# it under the terms of the GNU Lesser General Public License as published 

7# by the Free Software Foundation; version 2.1 only. 

8# 

9# This program is distributed in the hope that it will be useful, 

10# but WITHOUT ANY WARRANTY; without even the implied warranty of 

11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 

12# GNU Lesser General Public License for more details. 

13# 

14# You should have received a copy of the GNU Lesser General Public License 

15# along with this program; if not, write to the Free Software Foundation, Inc., 

16# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 

17 

18from sm_typing import override 

19 

20import SR 

21import VDI 

22import SRCommand 

23import util 

24import os 

25import xs_errors 

26from vditype import VdiType 

27 

28CAPABILITIES = ["VDI_ATTACH", "VDI_DETACH", "VDI_CLONE", "VDI_SNAPSHOT", 

29 "SR_SCAN", "SR_ATTACH", "SR_DETACH"] 

30CONFIGURATION = ['location', '/dev/shm subdirectory'] 

31DRIVER_INFO = { 

32 'name': 'SHM', 

33 'description': 'Handles shared memory virtual disks', 

34 'vendor': 'Citrix Systems Inc.', 

35 'copyright': '(c) 2009 Citrix Systems, Inc.', 

36 'driver_version': '1.0', 

37 'required_api_version': '1.0', 

38 'capabilities': CAPABILITIES, 

39 'configuration': CONFIGURATION 

40 } 

41 

42TYPE = "shm" 

43 

44 

45class SHMSR(SR.SR): 

46 """Shared memory storage repository""" 

47 

48 def _loadvdis(self): 

49 """Scan the location directory.""" 

50 if self.vdis: 

51 return 

52 

53 try: 

54 for name in util.listdir(self.dconf['location']): 

55 if name != "": 

56 self.vdis[name] = SHMVDI(self, util.gen_uuid(), name) 

57 except: 

58 pass 

59 

60 @override 

61 @staticmethod 

62 def handles(type) -> bool: 

63 """Do we handle this type?""" 

64 if type == TYPE: 

65 return True 

66 return False 

67 

68 @override 

69 def content_type(self, sr_uuid) -> str: 

70 """Returns the content_type XML""" 

71 return super(SHMSR, self).content_type(sr_uuid) 

72 

73 @override 

74 def vdi(self, uuid) -> VDI.VDI: 

75 """Create a VDI class""" 

76 if 'vdi_location' in self.srcmd.params: 

77 return SHMVDI(self, uuid, self.srcmd.params['vdi_location']) 

78 else: 

79 return SHMVDI(self, uuid, self.srcmd.params['device_config']['location']) 

80 

81 @override 

82 def load(self, sr_uuid) -> None: 

83 """Initialises the SR""" 

84 if 'location' not in self.dconf: 

85 raise xs_errors.XenError('ConfigLocationMissing') 

86 

87 self.sr_vditype = 'file' 

88 self.physical_size = 0 

89 self.physical_utilisation = 0 

90 self.virtual_allocation = 0 

91 

92 @override 

93 def attach(self, sr_uuid) -> None: 

94 """Std. attach""" 

95 self._loadvdis() 

96 

97 @override 

98 def detach(self, sr_uuid) -> None: 

99 """Std. detach""" 

100 pass 

101 

102 @override 

103 def scan(self, sr_uuid) -> None: 

104 """Scan""" 

105 self._loadvdis() 

106 super(SHMSR, self).scan(sr_uuid) 

107 

108 @override 

109 def create(self, sr_uuid, size) -> None: 

110 self.attach(sr_uuid) 

111 self.detach(sr_uuid) 

112 

113 

114class SHMVDI(VDI.VDI): 

115 @override 

116 def load(self, vdi_uuid) -> None: 

117 try: 

118 stat = os.stat(self.path) 

119 self.utilisation = int(stat.st_size) 

120 self.size = int(stat.st_size) 

121 except: 

122 pass 

123 

124 def __init__(self, mysr, uuid, filename): 

125 self.uuid = uuid 

126 self.path = os.path.join(mysr.dconf['location'], filename) 

127 VDI.VDI.__init__(self, mysr, None) 

128 self.label = filename 

129 self.location = filename 

130 self.vdi_type = VdiType.FILE 

131 self.read_only = True 

132 self.shareable = True 

133 self.sm_config = {} 

134 

135 @override 

136 def detach(self, sr_uuid, vdi_uuid) -> None: 

137 pass 

138 

139 @override 

140 def clone(self, sr_uuid, vdi_uuid) -> str: 

141 return self.get_params() 

142 

143 @override 

144 def snapshot(self, sr_uuid, vdi_uuid) -> str: 

145 return self.get_params() 

146 

147if __name__ == '__main__': 

148 SRCommand.run(SHMSR, DRIVER_INFO) 

149else: 

150 SR.registerSR(SHMSR)