lib/deploy: Add support for overlay initrds

apidoc/ostree-sections.txt

@@ -37,6 +37,8 @@ ostree_bootconfig_parser_write
 ostree_bootconfig_parser_write_at
 ostree_bootconfig_parser_set
 ostree_bootconfig_parser_get
+ostree_bootconfig_parser_set_overlay_initrds
+ostree_bootconfig_parser_get_overlay_initrds
 <SUBSECTION Standard>
 OSTREE_BOOTCONFIG_PARSER
 OSTREE_IS_BOOTCONFIG_PARSER
@@ -545,7 +547,10 @@ ostree_sysroot_write_deployments
 ostree_sysroot_write_deployments_with_options
 ostree_sysroot_write_origin_file
 ostree_sysroot_stage_tree
+ostree_sysroot_stage_tree_with_options
+ostree_sysroot_stage_overlay_initrd
 ostree_sysroot_deploy_tree
+ostree_sysroot_deploy_tree_with_options
 ostree_sysroot_get_merge_deployment
 ostree_sysroot_query_deployments_for
 ostree_sysroot_origin_new_from_refspec

src/libostree/libostree-devel.sym

@@ -24,6 +24,11 @@ global:
    */
   ostree_repo_static_delta_execute_offline_with_signature;
   ostree_repo_static_delta_verify_signature;
+  ostree_bootconfig_parser_get_overlay_initrds;
+  ostree_bootconfig_parser_set_overlay_initrds;
+  ostree_sysroot_deploy_tree_with_options;
+  ostree_sysroot_stage_tree_with_options;
+  ostree_sysroot_stage_overlay_initrd;
 } LIBOSTREE_2020.4;
 
 /* Stub section for the stable release *after* this development one; don't

src/libostree/ostree-bootconfig-parser.c

@@ -30,6 +30,9 @@ struct _OstreeBootconfigParser
   const char   *separators;
 
   GHashTable   *options;
+
+  /* Additional initrds; the primary initrd is in options. */
+  char        **overlay_initrds;
 };
 
 typedef GObjectClass OstreeBootconfigParserClass;
@@ -50,6 +53,8 @@ ostree_bootconfig_parser_clone (OstreeBootconfigParser *self)
   GLNX_HASH_TABLE_FOREACH_KV (self->options, const char*, k, const char*, v)
     g_hash_table_replace (parser->options, g_strdup (k), g_strdup (v));
 
+  parser->overlay_initrds = g_strdupv (self->overlay_initrds);
+
   return parser;
 }
 
@@ -76,6 +81,8 @@ ostree_bootconfig_parser_parse_at (OstreeBootconfigParser  *self,
   if (!contents)
     return FALSE;
 
+  g_autoptr(GPtrArray) overlay_initrds = NULL;
+
   g_auto(GStrv) lines = g_strsplit (contents, "\n", -1);
   for (char **iter = lines; *iter; iter++)
     {
@@ -87,8 +94,19 @@ ostree_bootconfig_parser_parse_at (OstreeBootconfigParser  *self,
           items = g_strsplit_set (line, self->separators, 2);
           if (g_strv_length (items) == 2 && items[0][0] != '\0')
             {
-              g_hash_table_insert (self->options, items[0], items[1]);
-              g_free (items); /* Transfer ownership */
+              if (g_str_equal (items[0], "initrd") &&
+                  g_hash_table_contains (self->options, "initrd"))
+                {
+                  if (!overlay_initrds)
+                    overlay_initrds = g_ptr_array_new_with_free_func (g_free);
+                  g_ptr_array_add (overlay_initrds, items[1]);
+                  g_free (items[0]);
+                }
+              else
+                {
+                  g_hash_table_insert (self->options, items[0], items[1]);
+                }
+              g_free (items); /* Free container; we stole the elements */
             }
           else
             {
@@ -97,6 +115,12 @@ ostree_bootconfig_parser_parse_at (OstreeBootconfigParser  *self,
         }
     }
 
+  if (overlay_initrds)
+    {
+      g_ptr_array_add (overlay_initrds, NULL);
+      self->overlay_initrds = (char**)g_ptr_array_free (g_steal_pointer (&overlay_initrds), FALSE);
+    }
+
   self->parsed = TRUE;
 
   return TRUE;
@@ -127,6 +151,41 @@ ostree_bootconfig_parser_get (OstreeBootconfigParser  *self,
   return g_hash_table_lookup (self->options, key);
 }
 
+/**
+ * ostree_bootconfig_parser_set_overlay_initrds:
+ * @self: Parser
+ * @initrds: (array zero-terminated=1) (transfer none) (allow-none): Array of overlay
+ *    initrds or %NULL to unset.
+ *
+ * These are rendered as additional `initrd` keys in the final bootloader configs. The
+ * base initrd is part of the primary keys.
+ *
+ * Since: 2020.7
+ */
+void
+ostree_bootconfig_parser_set_overlay_initrds (OstreeBootconfigParser  *self,
+                                              char                   **initrds)
+{
+  g_assert (g_hash_table_contains (self->options, "initrd"));
+  g_strfreev (self->overlay_initrds);
+  self->overlay_initrds = g_strdupv (initrds);
+}
+
+/**
+ * ostree_bootconfig_parser_get_overlay_initrds:
+ * @self: Parser
+ *
+ * Returns: (array zero-terminated=1) (transfer none) (nullable): Array of initrds or %NULL
+ * if none are set.
+ *
+ * Since: 2020.7
+ */
+char**
+ostree_bootconfig_parser_get_overlay_initrds (OstreeBootconfigParser  *self)
+{
+  return self->overlay_initrds;
+}
+
 static void
 write_key (OstreeBootconfigParser    *self,
            GString                   *buf,
@@ -165,6 +224,15 @@ ostree_bootconfig_parser_write_at (OstreeBootconfigParser   *self,
         }
     }
 
+  /* Write overlay initrds */
+  if (self->overlay_initrds && (g_strv_length (self->overlay_initrds) > 0))
+    {
+      /* we should've written the primary initrd already */
+      g_assert (g_hash_table_contains (keys_written, "initrd"));
+      for (char **it = self->overlay_initrds; it && *it; it++)
+        write_key (self, buf, "initrd", *it);
+    }
+
   /* Write unknown fields */
   GLNX_HASH_TABLE_FOREACH_KV (self->options, const char*, k, const char*, v)
     {
@@ -197,6 +265,7 @@ ostree_bootconfig_parser_finalize (GObject *object)
 {
   OstreeBootconfigParser *self = OSTREE_BOOTCONFIG_PARSER (object);
 
+  g_strfreev (self->overlay_initrds);
   g_hash_table_unref (self->options);
 
   G_OBJECT_CLASS (ostree_bootconfig_parser_parent_class)->finalize (object);

src/libostree/ostree-bootconfig-parser.h

@@ -73,5 +73,11 @@ _OSTREE_PUBLIC
 const char *ostree_bootconfig_parser_get (OstreeBootconfigParser  *self,
                                           const char      *key);
 
+_OSTREE_PUBLIC
+void ostree_bootconfig_parser_set_overlay_initrds (OstreeBootconfigParser  *self,
+                                                   char                   **initrds);
+
+_OSTREE_PUBLIC
+char** ostree_bootconfig_parser_get_overlay_initrds (OstreeBootconfigParser  *self);
 
 G_END_DECLS

src/libostree/ostree-deployment-private.h

@@ -37,6 +37,8 @@ G_BEGIN_DECLS
  * @origin: How to construct an upgraded version of this tree
  * @unlocked: The unlocked state
  * @staged: TRUE iff this deployment is staged
+ * @overlay_initrds: Checksums of staged additional initrds for this deployment
+ * @overlay_initrds_id: Unique ID generated from initrd checksums; used to compare deployments
  */
 struct _OstreeDeployment
 {
@@ -52,8 +54,15 @@ struct _OstreeDeployment
   GKeyFile *origin;
   OstreeDeploymentUnlockedState unlocked;
   gboolean staged;
+  char **overlay_initrds;
+  char *overlay_initrds_id;
 };
 
 void _ostree_deployment_set_bootcsum (OstreeDeployment *self, const char *bootcsum);
 
+void _ostree_deployment_set_overlay_initrds (OstreeDeployment *self,
+                                             char **overlay_initrds);
+
+char** _ostree_deployment_get_overlay_initrds (OstreeDeployment *self);
+
 G_END_DECLS

src/libostree/ostree-deployment.c

@@ -158,6 +158,34 @@ _ostree_deployment_set_bootcsum (OstreeDeployment *self,
   self->bootcsum = g_strdup (bootcsum);
 }
 
+void
+_ostree_deployment_set_overlay_initrds (OstreeDeployment *self,
+                                        char            **overlay_initrds)
+{
+  g_clear_pointer (&self->overlay_initrds, g_strfreev);
+  g_clear_pointer (&self->overlay_initrds_id, g_free);
+
+  if (!overlay_initrds || g_strv_length (overlay_initrds) == 0)
+    return;
+
+  /* Generate a unique ID representing this combination of overlay initrds. This is so that
+   * ostree_sysroot_write_deployments_with_options() can easily compare initrds when
+   * comparing deployments for whether a bootswap is necessary. We could be fancier here but
+   * meh... this works. */
+  g_autoptr(GString) id = g_string_new (NULL);
+  for (char **it = overlay_initrds; it && *it; it++)
+    g_string_append (id, *it);
+
+  self->overlay_initrds = g_strdupv (overlay_initrds);
+  self->overlay_initrds_id = g_string_free (g_steal_pointer (&id), FALSE);
+}
+
+char**
+_ostree_deployment_get_overlay_initrds (OstreeDeployment *self)
+{
+  return self->overlay_initrds;
+}
+
 /**
  * ostree_deployment_clone:
  * @self: Deployment
@@ -175,6 +203,8 @@ ostree_deployment_clone (OstreeDeployment *self)
   new_bootconfig = ostree_bootconfig_parser_clone (self->bootconfig);
   ostree_deployment_set_bootconfig (ret, new_bootconfig);
 
+  _ostree_deployment_set_overlay_initrds (ret, self->overlay_initrds);
+
   if (self->origin)
     {
       g_autoptr(GKeyFile) new_origin = NULL;
@@ -238,6 +268,8 @@ ostree_deployment_finalize (GObject *object)
   g_free (self->bootcsum);
   g_clear_object (&self->bootconfig);
   g_clear_pointer (&self->origin, g_key_file_unref);
+  g_strfreev (self->overlay_initrds);
+  g_free (self->overlay_initrds_id);
 
   G_OBJECT_CLASS (ostree_deployment_parent_class)->finalize (object);
 }

src/libostree/ostree-sysroot-cleanup.c

@@ -298,6 +298,8 @@ cleanup_old_deployments (OstreeSysroot       *self,
     g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
   g_autoptr(GHashTable) active_boot_checksums =
     g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+  g_autoptr(GHashTable) active_overlay_initrds =
+    g_hash_table_new (g_str_hash, g_str_equal); /* borrows from deployment's bootconfig */
   for (guint i = 0; i < self->deployments->len; i++)
     {
       OstreeDeployment *deployment = self->deployments->pdata[i];
@@ -306,6 +308,11 @@ cleanup_old_deployments (OstreeSysroot       *self,
       /* Transfer ownership */
       g_hash_table_replace (active_deployment_dirs, deployment_path, deployment_path);
       g_hash_table_replace (active_boot_checksums, bootcsum, bootcsum);
+
+      OstreeBootconfigParser *bootconfig = ostree_deployment_get_bootconfig (deployment);
+      char **initrds = ostree_bootconfig_parser_get_overlay_initrds (bootconfig);
+      for (char **it = initrds; it && *it; it++)
+        g_hash_table_add (active_overlay_initrds, (char*)glnx_basename (*it));
     }
 
   /* Find all deployment directories, both active and inactive */
@@ -349,6 +356,42 @@ cleanup_old_deployments (OstreeSysroot       *self,
         return FALSE;
     }
 
+  /* Clean up overlay initrds */
+  glnx_autofd int overlays_dfd =
+    glnx_opendirat_with_errno (self->sysroot_fd, _OSTREE_SYSROOT_INITRAMFS_OVERLAYS, FALSE);
+  if (overlays_dfd < 0)
+    {
+      if (errno != ENOENT)
+        return glnx_throw_errno_prefix (error, "open(initrd_overlays)");
+    }
+  else
+    {
+      g_autoptr(GPtrArray) initrds_to_delete = g_ptr_array_new_with_free_func (g_free);
+      g_auto(GLnxDirFdIterator) dfd_iter = { 0, };
+      if (!glnx_dirfd_iterator_init_at (overlays_dfd, ".", TRUE, &dfd_iter, error))
+        return FALSE;
+      while (TRUE)
+        {
+          struct dirent *dent;
+          if (!glnx_dirfd_iterator_next_dent_ensure_dtype (&dfd_iter, &dent, cancellable, error))
+            return FALSE;
+          if (dent == NULL)
+            break;
+
+          /* there shouldn't be other file types there, but let's be conservative */
+          if (dent->d_type != DT_REG)
+            continue;
+
+          if (!g_hash_table_lookup (active_overlay_initrds, dent->d_name))
+            g_ptr_array_add (initrds_to_delete, g_strdup (dent->d_name));
+        }
+      for (guint i = 0; i < initrds_to_delete->len; i++)
+        {
+          if (!ot_ensure_unlinked_at (overlays_dfd, initrds_to_delete->pdata[i], error))
+            return FALSE;
+        }
+    }
+
   return TRUE;
 }