Fix handling of empty disks and partitions for raid menu

mdadm supports using whole disks and empty partitions.
Update model to define empty disks and empty partitions.
This allows one to construct a raid, and then use that raid
to construct further raid (raid0 multiple raid1s).

Signed-off-by: Ryan Harper <ryan.harper@canonical.com>

subiquity/models/actions.py

@@ -159,6 +159,10 @@ class PartitionAction(DiskAction):
     def path(self):
         return "{}{}".format(self.parent.action_id, self.partnum)
 
+    @property
+    def devpath(self):
+        return "/dev/{}".format(self.path)
+
     @property
     def size(self):
         return self._size

subiquity/models/blockdev.py

@@ -140,10 +140,22 @@ class Blockdev():
         self.lvm = []
         self.holder = {}
 
+    @property
+    def blocktype(self):
+        return self.baseaction.type
+
     @property
     def devpath(self):
         return self.disk.devpath
 
+    @property
+    def path(self):
+        return self.disk.devpath
+
+    @property
+    def model(self):
+        return self.disk.model
+
     @property
     def mounts(self):
         return self._mounts.values()
@@ -164,6 +176,11 @@ class Blockdev():
     def partitions(self):
         return self.disk.partitions
 
+    @property
+    def partnames(self):
+        return ['{}{}'.format(self.devpath, num) for (num, _) in
+                self.partitions.items()]
+
     @property
     def filesystems(self):
         return self._filesystems
@@ -182,6 +199,17 @@ class Blockdev():
             return True
         return False
 
+    @property
+    def available_partitions(self):
+        ''' return list of non-zero sized partitions
+            defined but not mounted or formatted or used in
+            raid, lvm, bcache'''
+        return [part.devpath for (num, part) in self.partitions.items()
+                if part.size > 0 and
+                   part.flags not in ['raid', 'lvm', 'bcache'] and
+                   (part.devpath not in self._mounts.keys() or
+                    part.devpath not in self._filesystems.keys())]
+
     @property
     def mounted(self):
         return self.is_mounted()
@@ -272,6 +300,10 @@ class Blockdev():
         log.debug('Partition Added')
         return new_size
 
+    def get_partition(self, devpath):
+        [partnum] = re.findall('\d+$', devpath)
+        return self.partitions[partnum]
+
     def set_holder(self, devpath, holdtype):
         self.holder[holdtype] = devpath
 

subiquity/models/filesystem.py

@@ -15,6 +15,7 @@
 
 import json
 import logging
+import re
 
 from .blockdev import Blockdev, Raiddev
 import math
@@ -117,8 +118,7 @@ class FilesystemModel(ModelPolicy):
 
     def reset(self):
         log.debug('FilesystemModel: resetting disks')
-        for disk in self.devices.values():
-            disk.reset()
+        self.devices = {}
 
     def get_signal_by_name(self, selection):
         for x, y, z in self.get_signals():
@@ -152,11 +152,21 @@ class FilesystemModel(ModelPolicy):
                 self.info[disk] = self.prober.get_storage_info(disk)
 
     def get_disk(self, disk):
+        '''get disk object given path.  If provided a partition, then
+         return the parent disk.  /dev/sda2 --> /dev/sda obj'''
         log.debug('probe_storage: get_disk({})'.format(disk))
+
         if disk not in self.devices:
-            self.devices[disk] = Blockdev(disk, self.info[disk].serial,
-                                          self.info[disk].model,
-                                          size=self.info[disk].size)
+            try:
+                self.devices[disk] = Blockdev(disk, self.info[disk].serial,
+                                              self.info[disk].model,
+                                              size=self.info[disk].size)
+            except KeyError:
+                ''' if it looks like a partition, try again with
+                    parent device '''
+                if disk[-1].isdigit():
+                    return self.get_disk(re.split('[\d+]', disk)[0])
+
         return self.devices[disk]
 
     def get_available_disks(self):
@@ -228,6 +238,7 @@ class FilesystemModel(ModelPolicy):
             'hot_spares': '0',
             'chunk_size': '4K',
         }
+        could be /dev/sda1, /dev/md0, /dev/bcache1, /dev/vg_foo/foobar2?
         '''
         raid_devices = []
         spare_devices = []
@@ -238,11 +249,19 @@ class FilesystemModel(ModelPolicy):
         # and then one partition of type raid
         for (devpath, _, _) in all_devices:
             disk = self.get_disk(devpath)
-            disk.add_partition(1, disk.freespace, None, None, flag='raid')
-            if len(raid_devices) + nr_spares < len(all_devices):
-                raid_devices.append(disk)
+
+            # add or update a partition to be raid type
+            if disk.path != devpath:  # we must have got a partition
+                raiddev = disk.get_partition(devpath)
+                raiddev.flags = 'raid'
             else:
-                spare_devices.append(disk)
+                disk.add_partition(1, disk.freespace, None, None, flag='raid')
+                raiddev = disk
+
+            if len(raid_devices) + nr_spares < len(all_devices):
+                raid_devices.append(raiddev)
+            else:
+                spare_devices.append(raiddev)
 
         # auto increment md number based in registered devices
         raid_dev_name = '/dev/md{}'.format(len(self.raid_devices))
@@ -252,12 +271,13 @@ class FilesystemModel(ModelPolicy):
         raid_level = int(raidspec.get('raid_level'))
         raid_size = self.calculate_raid_size(raid_level, raid_devices,
                                              spare_devices)
+
         # create a Raiddev (pass in only the names)
         raid_dev = Raiddev(raid_dev_name, raid_serial, raid_model,
                            raid_parttype, raid_size,
-                           [d.devpath for d in raid_devices],
+                           [d.path for d in raid_devices],
                            raid_level,
-                           [d.devpath for d in spare_devices])
+                           [d.path for d in spare_devices])
 
         # add it to the model's info dict
         raid_dev_info = {
@@ -316,6 +336,31 @@ class FilesystemModel(ModelPolicy):
         log.debug('bootable check: no disks have been marked bootable')
         return False
 
+    def get_empty_disks(self):
+        ''' empty disk is one that does not have any
+            partitions, filesystems or mounts, and is non-zero size '''
+        empty = []
+        for dev in self.get_available_disks():
+            if len(dev.partitions) == 0 and \
+               len(dev.mounts) == 0 and \
+               len(dev.filesystems) == 0:
+                empty.append(dev)
+        log.debug('empty_disks: {}'.format(", ".join([dev.path for dev in empty])))
+        return empty
+
+    def get_empty_disk_names(self):
+        return [dev.disk.devpath for dev in self.get_empty_disks()]
+
+    def get_empty_partition_names(self):
+        ''' empty partitions have non-zero size, but are not part
+            of a filesystem or mount point or other raid '''
+        empty = []
+        for dev in self.get_available_disks():
+            empty += dev.available_partitions
+
+        log.debug('empty_partitions: {}'.format(", ".join(empty)))
+        return empty
+
     def get_available_disk_names(self):
         return [dev.disk.devpath for dev in self.get_available_disks()]
 

subiquity/ui/views/raid.py

@@ -47,18 +47,27 @@ class RaidView(ViewPolicy):
         items = [
             Text("DISK SELECTION")
         ]
-        avail_disks = self.model.get_available_disk_names()
-        if len(avail_disks) == 0:
+
+        # raid can use empty whole disks, or empty partitions
+        avail_disks = self.model.get_empty_disk_names()
+        avail_parts = self.model.get_empty_partition_names()
+        avail_devs = sorted(avail_disks + avail_parts)
+        if len(avail_devs) == 0:
             return items.append(
                 [Color.info_minor(Text("No available disks."))])
 
-        for dname in avail_disks:
-            disk = self.model.get_disk_info(dname)
-            #device = self.model.get_disk(dname)
-            disk_sz = _humanize_size(disk.size)
-            disk_string = "{}     {},     {}".format(disk.name,
+        for dname in avail_devs:
+            device = self.model.get_disk(dname)
+            if device.path != dname:
+                # we've got a partition
+                raiddev = device.get_partition(dname)
+            else:
+                raiddev = device
+
+            disk_sz = _humanize_size(raiddev.size)
+            disk_string = "{}     {},     {}".format(dname,
                                                      disk_sz,
-                                                     disk.model)
+                                                     device.model)
             log.debug('raid: disk_string={}'.format(disk_string))
             self.selected_disks.append(CheckBox(disk_string))