From 0a39a937e2d69faf71e41f948c6aa0af1cf6294e Mon Sep 17 00:00:00 2001
From: Davide Cavalca <davide@cavalca.name>
Date: Jul 10 2020 16:15:05 +0000
Subject: add basic support for btrfs subvolumes


---

diff --git a/appcreate/appliance.py b/appcreate/appliance.py
index 38a2a40..f5d7ec1 100644
--- a/appcreate/appliance.py
+++ b/appcreate/appliance.py
@@ -122,6 +122,7 @@ class ApplianceImageCreator(ImageCreator):
 
         #list of partitions from kickstart file
         parts = kickstart.get_partitions(self.ks)
+        
         # need to eliminate duplicate partitions
         # this is a bit of a hack but we assume the last partition for a given mount point is the one we want
         mountpoints = []
@@ -225,11 +226,21 @@ class ApplianceImageCreator(ImageCreator):
             else:
                 self.__instloop.add_partition(int(p.size), "sda", p.mountpoint, p.fstype)
 
+        # FIXME: this only works if there's just one btrfs partition
+        for p in parts:
+            if p.fstype == 'btrfs':
+                for s in self.ks.handler.btrfs.btrfsList:
+                    if s.subvol:
+                        self.__instloop.add_subvolume(p.mountpoint, s.mountpoint, s.name)
+
         try:
             self.__instloop.mount()
         except MountError as e:
             raise CreatorError("Failed mount disks : %s" % e)
 
+        if self.ks.handler.btrfs.btrfsList:
+            self.__instloop.setup_subvolumes()
+
         self._create_mkinitrd_config()
 
     def _kernel_cmdline_append(self):
diff --git a/appcreate/partitionedfs.py b/appcreate/partitionedfs.py
index 4769ce9..86e709c 100644
--- a/appcreate/partitionedfs.py
+++ b/appcreate/partitionedfs.py
@@ -47,6 +47,7 @@ class PartitionedMount(Mount):
                                  'offset': 0 } # Offset of next partition
 
         self.partitions = []
+        self.subvolumes = []
         self.mapped = False
         self.mountOrder = []
         self.unmountOrder = []
@@ -64,6 +65,9 @@ class PartitionedMount(Mount):
                                 'UUID': None, # UUID for partition
                                 'num': None}) # Partition number
 
+    def add_subvolume(self, parent, mountpoint, name):
+        self.subvolumes.append({'parent': parent, 'mountpoint': mountpoint, 'name': name})
+
     def __format_disks(self):
         logging.debug("Formatting disks")
         for dev in list(self.disks.keys()):
@@ -240,6 +244,20 @@ class PartitionedMount(Mount):
                 pass
 
     def unmount(self):
+        if self.subvolumes:
+            ordered = []
+            others = []
+            for s in self.subvolumes:
+                if s['mountpoint'] == '/':
+                    others.append(s)
+                else:
+                    ordered.append(s)
+                    
+            ordered += others
+             
+            for s in ordered:
+                subprocess.call(['umount', s['mountpoint']])
+    
         for mp in self.unmountOrder:
             if mp == 'swap':
                 continue
@@ -256,6 +274,25 @@ class PartitionedMount(Mount):
                     pass
                 p['mount'] = None
 
+    def setup_subvolumes(self):
+        others = []
+        ordered = []
+        for s in self.subvolumes:
+            if s['mountpoint'] == '/':
+                ordered.append(s)
+            else:
+                others.append(s)
+  
+        ordered += others
+        for s in ordered:
+            base = "%s%s" % (self.mountdir, s['parent'])
+            path = "%s/%s" % (base, s['name'])
+            mountpath = "%s%s" % (self.mountdir, s['mountpoint'])
+            subprocess.call(['btrfs', 'subvol', 'create', path])
+            subprocess.call(['mkdir', '-p', mountpath])
+            device = subprocess.Popen(["findmnt", "-n", "-o", "SOURCE", base], stdout=subprocess.PIPE).communicate()[0].decode("utf-8").strip()
+            subprocess.call(['mount', '-t', 'btrfs', '-o', 'subvol=%s' % s['name'], device, mountpath])
+
     def mount(self):
         for dev in list(self.disks.keys()):
             d = self.disks[dev]