grub2/grub2-btrfs-04-grub2-install.patch

--- a/grub-core/osdep/unix/config.c
+++ b/grub-core/osdep/unix/config.c
@@ -207,6 +207,19 @@
   if (v)
     cfg->grub_distributor = xstrdup (v);
 
+  v = getenv ("SUSE_BTRFS_SNAPSHOT_BOOTING");
+  if (v)
+    {
+      if (grub_strncmp(v, "true", sizeof ("true") - 1) == 0)
+        {
+          cfg->is_suse_btrfs_snapshot_enabled = 1;
+        }
+      else
+        {
+          cfg->is_suse_btrfs_snapshot_enabled = 0;
+        }
+    }
+
   cfgfile = grub_util_get_config_filename ();
   if (!grub_util_is_regular (cfgfile))
     return;
@@ -230,8 +243,8 @@
       *ptr++ = *iptr;
     }
 
-  strcpy (ptr, "'; printf \"GRUB_ENABLE_CRYPTODISK=%s\\nGRUB_DISTRIBUTOR=%s\\n\" "
-	  "\"$GRUB_ENABLE_CRYPTODISK\" \"$GRUB_DISTRIBUTOR\"");
+  strcpy (ptr, "'; printf \"GRUB_ENABLE_CRYPTODISK=%s\\nGRUB_DISTRIBUTOR=%s\\nSUSE_BTRFS_SNAPSHOT_BOOTING=%s\\n\" "
+	  "\"$GRUB_ENABLE_CRYPTODISK\" \"$GRUB_DISTRIBUTOR\" \"$SUSE_BTRFS_SNAPSHOT_BOOTING\"");
 
   argv[2] = script;
   argv[3] = '\0';
--- a/include/grub/emu/config.h
+++ b/include/grub/emu/config.h
@@ -37,6 +37,7 @@
 {
   int is_cryptodisk_enabled;
   char *grub_distributor;
+  int is_suse_btrfs_snapshot_enabled;
 };
 
 void
--- a/util/config.c
+++ b/util/config.c
@@ -42,6 +42,16 @@
 	    cfg->is_cryptodisk_enabled = 1;
 	  continue;
 	}
+      if (grub_strncmp (ptr, "SUSE_BTRFS_SNAPSHOT_BOOTING=",
+			sizeof ("SUSE_BTRFS_SNAPSHOT_BOOTING=") - 1) == 0)
+	{
+	  ptr += sizeof ("SUSE_BTRFS_SNAPSHOT_BOOTING=") - 1;
+	  if (*ptr == '"' || *ptr == '\'')
+	    ptr++;
+	  if (grub_strncmp(ptr, "true", sizeof ("true") - 1) == 0)
+	    cfg->is_suse_btrfs_snapshot_enabled = 1;
+	  continue;
+	}
       if (grub_strncmp (ptr, "GRUB_DISTRIBUTOR=",
 			sizeof ("GRUB_DISTRIBUTOR=") - 1) == 0)
 	{
--- a/util/grub-install.c
+++ b/util/grub-install.c
@@ -857,6 +857,8 @@
 }
 #endif
 
+extern int use_relative_path_on_btrfs;
+
 int
 main (int argc, char *argv[])
 {
@@ -890,6 +892,9 @@
 
   grub_util_load_config (&config);
 
+  if (config.is_suse_btrfs_snapshot_enabled)
+    use_relative_path_on_btrfs = 1;
+
   if (!bootloader_id && config.grub_distributor)
     {
       char *ptr;
@@ -1426,6 +1431,16 @@
       fprintf (load_cfg_f, "set debug='%s'\n",
 	      debug_image);
     }
+
+  if (config.is_suse_btrfs_snapshot_enabled
+      && grub_strncmp(grub_fs->name, "btrfs", sizeof ("btrfs") - 1) == 0)
+    {
+      if (!load_cfg_f)
+        load_cfg_f = grub_util_fopen (load_cfg, "wb");
+      have_load_cfg = 1;
+      fprintf (load_cfg_f, "set btrfs_relative_path='y'\n");
+    }
+
   char *prefix_drive = NULL;
   char *install_drive = NULL;
 
--- a/grub-core/osdep/linux/getroot.c
+++ b/grub-core/osdep/linux/getroot.c
@@ -373,6 +373,7 @@
   return NULL;
 }
 
+int use_relative_path_on_btrfs = 0;
 
 char **
 grub_find_root_devices_from_mountinfo (const char *dir, char **relroot)
@@ -516,6 +517,12 @@
 	{
 	  ret = grub_find_root_devices_from_btrfs (dir);
 	  fs_prefix = get_btrfs_fs_prefix (entries[i].enc_path);
+	  if (use_relative_path_on_btrfs)
+	    {
+	      if (fs_prefix)
+	        free (fs_prefix);
+	      fs_prefix = xstrdup ("/");
+	    }
 	}
       else if (!retry && grub_strcmp (entries[i].fstype, "autofs") == 0)
 	{
--- a/util/grub-mkrelpath.c
+++ b/util/grub-mkrelpath.c
@@ -40,9 +40,12 @@
 };
 
 static struct argp_option options[] = {
+  {"relative",  'r', 0, 0, "use relative path on btrfs", 0},
   { 0, 0, 0, 0, 0, 0 }
 };
 
+extern int use_relative_path_on_btrfs;
+
 static error_t
 argp_parser (int key, char *arg, struct argp_state *state)
 {
@@ -52,6 +55,9 @@
 
   switch (key)
     {
+    case 'r':
+      use_relative_path_on_btrfs = 1;
+      break;
     case ARGP_KEY_ARG:
       if (state->arg_num == 0)
 	arguments->pathname = xstrdup (arg);