u-boot: add 'bootdir' to the generated uEnv.txt

When doing a full copy of:

$deployment/usr/lib/ostree-boot -> /boot/ostree/$os-$bootcsum/

U-Boot bootscript can use the 'bootdir' to find, for example,
the Device Tree (dtb) file, as in:

load ${dtype} ${disk}:${bootpart} ${a_fdt} ${bootdir}${dtbname}

Or u-boot external bootscript:

load ${dtype} ${disk}:${bootpart} ${a_scr} ${bootdir}${scriptname}

It could also be possible to point 'bootdir' directly to the
$deployment/usr/lib/ostree-boot, but this would add unnecessary
restrictions on what file system can be used for rootfs as u-boot,
for example, can not read from BTRFS. So having
bootdir=/boot/ostree/$os-$bootcsum/ is a better approach here, as
/boot can be on a separate partition with its own file system type.

Upstream-Status: Inappropriate [lmp specific]

Signed-off-by: Ricardo Salveti <[email protected]>

%% original patch: 0002-u-boot-add-bootdir-to-the-generated-uEnv.txt.patch

src/libostree/ostree-bootloader-uboot.c

@@ -106,6 +106,7 @@ create_config_from_boot_loader_entries (OstreeBootloaderUboot *self, int bootver
   g_autoptr (GPtrArray) boot_loader_configs = NULL;
   OstreeBootconfigParser *config;
   const char *val;
+  g_autofree char *bootdir = NULL;
 
   if (!_ostree_sysroot_read_boot_loader_configs (self->sysroot, bootversion, &boot_loader_configs,
                                                  cancellable, error))
@@ -129,6 +130,9 @@ create_config_from_boot_loader_entries (OstreeBootloaderUboot *self, int bootver
         }
       g_ptr_array_add (new_lines, g_strdup_printf ("kernel_image%s=/boot%s", index_suffix, val));
 
+      bootdir = strndup (val, strrchr(val, '/') - val);
+      g_ptr_array_add (new_lines, g_strdup_printf ("bootdir%s=/boot%s/", index_suffix, bootdir));
+
       val = ostree_bootconfig_parser_get (config, "initrd");
       if (val)
         g_ptr_array_add (new_lines, g_strdup_printf ("ramdisk_image%s=/boot%s", index_suffix, val));

tests/test-bootdir-update.sh

@@ -35,5 +35,6 @@ assert_has_file sysroot/boot/ostree/testos-${bootcsum}/1
 assert_file_has_content sysroot/boot/ostree/testos-${bootcsum}/1 "1"
 assert_has_file sysroot/boot/ostree/testos-${bootcsum}/subdir/2
 assert_file_has_content sysroot/boot/ostree/testos-${bootcsum}/subdir/2 "2"
+assert_file_has_content sysroot/boot/uEnv.txt "bootdir="
 
 echo "ok boot dir with .ostree-bootcsumdir-source"