Merge branch 'baserock/richardmaw-os/unify-namespace-logic'

This removes the last case of global mounting that could cause issues
for being able to run multiple builds in parallel.

There's still concurrent access to caches and git servers that could
cause issues, but with this, it's possible to run morph in the
test-suite in parallel.

Reviewed-by: Daniel Silverstone
Reviewed-by: Sam Thursfield

1 files changed, 16 insertions, 53 deletions

diff --git a/morphlib/stagingarea.py b/morphlib/stagingarea.py
index 25e33b3f..b676d4db 100644
--- a/morphlib/stagingarea.py
+++ b/morphlib/stagingarea.py
@@ -45,7 +45,6 @@ class StagingArea(object):
         self.dirname = dirname
         self.builddirname = None
         self.destdirname = None
-        self.mounted = []
         self._bind_readonly_mount = None
 
         self.use_chroot = use_chroot
@@ -224,23 +223,6 @@ class StagingArea(object):
             os.makedirs(ccache_destdir)
         return ccache_repodir
 
-    def do_mounts(self, setup_mounts):  # pragma: no cover
-        if not setup_mounts:
-            return
-        for mount_point, mount_type, source in self.to_mount:
-            logging.debug('Mounting %s in staging area' % mount_point)
-            path = os.path.join(self.dirname, mount_point)
-            if not os.path.exists(path):
-                os.makedirs(path)
-            morphlib.fsutils.mount(self._app.runcmd, source, path, mount_type)
-            self.mounted.append(path)
-        return
-
-    def do_unmounts(self):  # pragma: no cover
-        for path in reversed(self.mounted):
-            logging.debug('Unmounting %s in staging area' % path)
-            morphlib.fsutils.unmount(self._app.runcmd, path)
-
     def chroot_open(self, source, setup_mounts): # pragma: no cover
         '''Setup staging area for use as a chroot.'''
 
@@ -251,8 +233,6 @@ class StagingArea(object):
         self.builddirname = builddir
         self.destdirname = destdir
 
-        self.do_mounts(setup_mounts)
-
         return builddir, destdir
 
     def chroot_close(self): # pragma: no cover
@@ -261,22 +241,17 @@ class StagingArea(object):
         This should be called after the staging area is no longer needed.
 
         '''
-
-        self.do_unmounts()
+        # No cleanup is currently required
+        pass
 
     def runcmd(self, argv, **kwargs):  # pragma: no cover
         '''Run a command in a chroot in the staging area.'''
         assert 'env' not in kwargs
-        kwargs['env'] = self.env
+        kwargs['env'] = dict(self.env)
         if 'extra_env' in kwargs:
             kwargs['env'].update(kwargs['extra_env'])
             del kwargs['extra_env']
 
-        if 'cwd' in kwargs:
-            cwd = kwargs['cwd']
-            del kwargs['cwd']
-        else:
-            cwd = '/'
         ccache_dir = kwargs.pop('ccache_dir', None)
 
         chroot_dir = self.dirname if self.use_chroot else '/'
@@ -289,40 +264,28 @@ class StagingArea(object):
                              for d in staging_dirs]
         if not self.use_chroot:
             do_not_mount_dirs += [temp_dir]
-
         logging.debug("Not mounting dirs %r" % do_not_mount_dirs)
 
-        real_argv = ['linux-user-chroot', '--chdir', cwd, '--unshare-net']
-        for d in morphlib.fsutils.invert_paths(os.walk(chroot_dir),
-                                               do_not_mount_dirs):
-            if not os.path.islink(d):
-                real_argv += ['--mount-readonly', self.relative(d)]
-
-        if self.use_chroot:
-            proc_target = os.path.join(self.dirname, 'proc')
-            if not os.path.exists(proc_target):
-                os.makedirs(proc_target)
-            real_argv += ['--mount-proc', self.relative(proc_target)]
-
+        mount_proc = self.use_chroot
         if ccache_dir and not self._app.settings['no-ccache']:
             ccache_target = os.path.join(
                     self.dirname, kwargs['env']['CCACHE_DIR'].lstrip('/'))
-            real_argv += ['--mount-bind', ccache_dir,
-                          self.relative(ccache_target)]
-
-        real_argv += [chroot_dir]
-
-        real_argv += argv
+            binds = ((ccache_dir, ccache_target),)
+        else:
+            binds = ()
 
+        cmdline = morphlib.util.containerised_cmdline(
+                    argv, cwd=kwargs.pop('cwd', '/'),
+                    root=chroot_dir, mounts=self.to_mount,
+                    binds=binds, mount_proc=mount_proc,
+                    writable_paths=do_not_mount_dirs)
         try:
-            if 'logfile' in kwargs and kwargs['logfile'] != None:
-                logfile = kwargs['logfile']
-                del kwargs['logfile']
-
+            if kwargs.get('logfile') != None:
+                logfile = kwargs.pop('logfile')
                 teecmd = ['tee', '-a', logfile]
-                return self._app.runcmd(real_argv, teecmd, **kwargs)
+                return self._app.runcmd(cmdline, teecmd, **kwargs)
             else:
-                return self._app.runcmd(real_argv, **kwargs)
+                return self._app.runcmd(cmdline, **kwargs)
         except cliapp.AppException as e:
             raise cliapp.AppException('In staging area %s: running '
                                       'command \'%s\' failed.' %