[block] Allow for additional SAN boot parameters alongside filename

The drive specification alone does not necessarily contain enough
information to perform a SAN boot (or local disk boot) under UEFI.  If
the next-stage bootloader is installed in the EFI system partition
under a non-standard name (e.g. "\EFI\debian\grubx64.efi") then this
explicit boot filename must also be specified.

Generalise this concept to use a "SAN boot configuration parameters"
structure (currently containing only the optional explicit boot
filename), to allow for easy expansion to provide other parameters
such as the partition UUID or volume label.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 13 insertions, 10 deletions

diff --git a/src/interface/efi/efi_block.c b/src/interface/efi/efi_block.c
index 11d11156b..e81d6bb7e 100644
--- a/src/interface/efi/efi_block.c
+++ b/src/interface/efi/efi_block.c
@@ -583,13 +583,13 @@ static int efi_block_filename ( unsigned int drive, EFI_HANDLE handle,
  * @v drive		Drive number
  * @v handle		Filesystem handle
  * @v path		Block device path
- * @v filename		Filename (or NULL to use default)
+ * @v config		Boot configuration parameters
  * @v fspath		Filesystem device path to fill in
  * @ret rc		Return status code
  */
 static int efi_block_match ( unsigned int drive, EFI_HANDLE handle,
 			     EFI_DEVICE_PATH_PROTOCOL *path,
-			     const char *filename,
+			     struct san_boot_config *config,
 			     EFI_DEVICE_PATH_PROTOCOL **fspath ) {
 	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
 	EFI_GUID *protocol = &efi_device_path_protocol_guid;
@@ -624,8 +624,10 @@ static int efi_block_match ( unsigned int drive, EFI_HANDLE handle,
 	       drive, efi_devpath_text ( u.path ) );
 
 	/* Check if filesystem contains boot filename */
-	if ( ( rc = efi_block_filename ( drive, handle, filename ) ) != 0 )
+	if ( ( rc = efi_block_filename ( drive, handle,
+					 config->filename ) ) != 0 ) {
 		goto err_filename;
+	}
 
 	/* Success */
 	rc = 0;
@@ -642,12 +644,12 @@ static int efi_block_match ( unsigned int drive, EFI_HANDLE handle,
  *
  * @v drive		Drive number
  * @v handle		Block device handle
- * @v filename		Filename (or NULL to use default)
+ * @v config		Boot configuration parameters
  * @v fspath		Filesystem device path to fill in
  * @ret rc		Return status code
  */
 static int efi_block_scan ( unsigned int drive, EFI_HANDLE handle,
-			    const char *filename,
+			    struct san_boot_config *config,
 			    EFI_DEVICE_PATH_PROTOCOL **fspath ) {
 	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
 	EFI_GUID *protocol = &efi_device_path_protocol_guid;
@@ -690,7 +692,7 @@ static int efi_block_scan ( unsigned int drive, EFI_HANDLE handle,
 
 		/* Check for a matching filesystem */
 		if ( ( rc = efi_block_match ( drive, handles[i], u.path,
-					      filename, fspath ) ) != 0 )
+					      config, fspath ) ) != 0 )
 			continue;
 
 		break;
@@ -847,10 +849,11 @@ static int efi_block_local ( EFI_HANDLE handle ) {
  * Boot from EFI block device
  *
  * @v drive		Drive number
- * @v filename		Filename (or NULL to use default)
+ * @v config		Boot configuration parameters
  * @ret rc		Return status code
  */
-static int efi_block_boot ( unsigned int drive, const char *filename ) {
+static int efi_block_boot ( unsigned int drive,
+			    struct san_boot_config *config ) {
 	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
 	EFI_DEVICE_PATH_PROTOCOL *fspath = NULL;
 	EFI_HANDLE *handles;
@@ -943,13 +946,13 @@ static int efi_block_boot ( unsigned int drive, const char *filename ) {
 		DBGC ( vdrive, "EFIBLK %#02x attempting to boot\n", vdrive );
 
 		/* Scan for a matching filesystem within this drive */
-		if ( ( rc = efi_block_scan ( vdrive, handle, filename,
+		if ( ( rc = efi_block_scan ( vdrive, handle, config,
 					     &fspath ) ) != 0 ) {
 			continue;
 		}
 
 		/* Attempt to boot from the matched filesystem */
-		rc = efi_block_exec ( vdrive, fspath, filename );
+		rc = efi_block_exec ( vdrive, fspath, config->filename );
 		break;
 	}