Class: QemuToolkit::VMStorage

Inherits:
Object
  • Object
show all
Defined in:
lib/qemu-toolkit/vm_storage.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, backend) ⇒ VMStorage

Returns a new instance of VMStorage.



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# File 'lib/qemu-toolkit/vm_storage.rb', line 3

def initialize(name, backend)
  @name = name
  @backend = backend
end

Instance Attribute Details

#backend ⇒ Object (readonly)

Returns the value of attribute backend.



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# File 'lib/qemu-toolkit/vm_storage.rb', line 8

def backend
  @backend
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/qemu-toolkit/vm_storage.rb', line 9

def name
  @name
end

Instance Method Details

#clone(target_name, version) ⇒ Object

Clones this vm storage to the given target name. If target_name is given without pool part, clone will live in the same pool as its parent vm storage. The version argument specifies which version should be cloned and must be a recursive snapshot on the parent vm.

Raises:

  • (ArgumentError) 


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# File 'lib/qemu-toolkit/vm_storage.rb', line 23

def clone(target_name, version)
  raise ArgumentError, "Must specify the dataset path for cloning." \
    if relative_name?
  
  path, vm_name = split
  target_path = join path, target_name
  backend.zfs :clone, "#@name@#{version}", target_path
  
  backend.disks(name).each do |disk_path|
    disk_name = subtract @name, disk_path
    target_disk_name = join path, target_name, disk_name
    backend.zfs :clone, "#{disk_path}@#{version}", target_disk_name
  end
  
  # Mark the dataset as hidden
  backend.zfs :set, "#{QemuToolkit::EXPORT_TAG}=false", join(path, target_name)
end

#create(sizes) ⇒ Object 



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# File 'lib/qemu-toolkit/vm_storage.rb', line 11

def create(sizes)
  backend.zfs :create, "-o #{QemuToolkit::EXPORT_TAG}=false", name
  sizes.each_with_index do |size, idx|
    backend.zfs :create, "-V #{size}", name + "/disk#{idx+1}"
  end
end

#exist? ⇒ Boolean

Returns true if the storage seems to exist and be a valid vm storage.

Returns:

  • (Boolean) 


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# File 'lib/qemu-toolkit/vm_storage.rb', line 85

def exist?
  ! export_tag.nil?
end

#export ⇒ Object

Exports all disks of a virtual machine (called ‘diskN’ below the main dataset) as LUNs below a single iqn for the machine.



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# File 'lib/qemu-toolkit/vm_storage.rb', line 44

def export
  fail "VM storage #{name} does not exist." unless exist?
  fail "VM storage #{name} is already exported." if exported?
  
  path, vm_name = split
  
  backend.stmfadm 'create-tg', vm_name
  
  backend.disks(name).each do |disk_path|
    output = backend.stmfadm 'create-lu', "/dev/zvol/rdsk/"+disk_path
    
    md=output.match /Logical unit created: ([0-9A-F]+)/
    raise "Could not parse created LU. (#{output.inspect})" unless md
    
    backend.stmfadm 'add-view', "-t #{vm_name}", md[1]
  end
  
  backend.stmfadm 'add-tg-member', "-g #{vm_name}", iqn
  backend.itadm 'create-target', "-n #{iqn}", '-t frontend'
  
  # Mark the dataset as exported
  backend.zfs :set, "#{QemuToolkit::EXPORT_TAG}=true", name
end

#exported? ⇒ Boolean

Returns true if the storage exists and is exported currently. Returns false if the storage exists and is not exported. In all other cases this method returns nil.

Returns:

  • (Boolean) 


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# File 'lib/qemu-toolkit/vm_storage.rb', line 72

def exported?
  case (export_tag || '').chomp
    when 'true'
      return true
    when 'false'
      return false
  end
  
  return nil
end

#hide ⇒ Object

Hides the vm storage from iSCSI.



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# File 'lib/qemu-toolkit/vm_storage.rb', line 91

def hide
  fail "VM storage #{name} does not exist." unless exist?
  fail "VM storage #{name} is already hidden." unless exported?

  path, vm_name = split
  
  raise "Cannot find an exported dataset named #{name}. " \
    unless exported?
  
  backend.stmfadm 'offline-target', iqn
  backend.itadm 'delete-target', iqn
  
  # Parse existing lus, look for vm_name/diskN
  lus = backend.stmfadm 'list-lu', '-v'
  last_lu = nil
  lus.each_line do |line|
    if md=line.match(/LU Name: ([0-9A-F]+)/)
      last_lu = md[1]
    end
    if line.include?('Data File') && 
      line.include?('/dev/zvol/rdsk') && 
      line.match(%r(/#{Regexp.escape(vm_name)}/disk\d+))
      
      backend.stmfadm 'delete-lu', last_lu
    end
  end
  
  backend.stmfadm 'delete-tg', vm_name

  # Mark the dataset as hidden
  backend.zfs :set, "#{QemuToolkit::EXPORT_TAG}=false", name
end

#iqn ⇒ Object 



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# File 'lib/qemu-toolkit/vm_storage.rb', line 135

def iqn
  _, n = split
  "iqn.2012-01.com.qemu-toolkit:#{n}"
end

#relative_name? ⇒ Boolean

Returns whether the name used to construct this instance is relative or absolute. A relative name identifies a storage within its pool, an absolute name identifies it within the whole system. 

VMStorage.new('foo').relative_name?     # => true
VMStorage.new('b1/foo').relative_name?  # => false

Returns:

  • (Boolean) 


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# File 'lib/qemu-toolkit/vm_storage.rb', line 131

def relative_name?
  @name.index('/') == nil
end