efi_loader: define internal implementations of install/uninstallmultiple

A following patch is cleaning up the core EFI code trying to remove
sequences of efi_create_handle, efi_add_protocol.

Although this works fine there's a problem with the latter since it is
usually combined with efi_delete_handle() which blindly removes all
protocols on a handle and deletes the handle.  We should try to adhere to
the EFI spec which only deletes a handle if the last instance of a protocol
has been removed.  Another problem is that efi_delete_handle() never checks
for opened protocols,  but the EFI spec defines that the caller is
responsible for ensuring that there are no references to a protocol
interface that is going to be removed.

So let's fix this by replacing all callsites of
efi_create_handle(), efi_add_protocol() , efi_delete_handle() with
Install/UninstallMultipleProtocol.

In order to do that redefine functions that can be used by the U-Boot
proper internally and add '_ext' variants that will be used from the
EFI API

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

1 files changed, 159 insertions, 55 deletions

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 1bfd094e89..e776d25830 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -2590,35 +2590,31 @@ found:
 }
 
 /**
- * efi_install_multiple_protocol_interfaces() - Install multiple protocol
+ * efi_install_multiple_protocol_interfaces_int() - Install multiple protocol
  *                                              interfaces
  * @handle: handle on which the protocol interfaces shall be installed
- * @...:    NULL terminated argument list with pairs of protocol GUIDS and
- *          interfaces
+ * @argptr: va_list of args
  *
- * This function implements the MultipleProtocolInterfaces service.
- *
- * See the Unified Extensible Firmware Interface (UEFI) specification for
- * details.
+ * Core functionality of efi_install_multiple_protocol_interfaces
+ * Must not be called directly
  *
  * Return: status code
  */
-efi_status_t EFIAPI efi_install_multiple_protocol_interfaces
-				(efi_handle_t *handle, ...)
+static efi_status_t EFIAPI
+efi_install_multiple_protocol_interfaces_int(efi_handle_t *handle,
+					     efi_va_list argptr)
 {
-	EFI_ENTRY("%p", handle);
-
-	efi_va_list argptr;
 	const efi_guid_t *protocol;
 	void *protocol_interface;
 	efi_handle_t old_handle;
-	efi_status_t r = EFI_SUCCESS;
+	efi_status_t ret = EFI_SUCCESS;
 	int i = 0;
+	efi_va_list argptr_copy;
 
 	if (!handle)
-		return EFI_EXIT(EFI_INVALID_PARAMETER);
+		return EFI_INVALID_PARAMETER;
 
-	efi_va_start(argptr, handle);
+	efi_va_copy(argptr_copy, argptr);
 	for (;;) {
 		protocol = efi_va_arg(argptr, efi_guid_t*);
 		if (!protocol)
@@ -2628,104 +2624,212 @@ efi_status_t EFIAPI efi_install_multiple_protocol_interfaces
 		if (!guidcmp(protocol, &efi_guid_device_path)) {
 			struct efi_device_path *dp = protocol_interface;
 
-			r = EFI_CALL(efi_locate_device_path(protocol, &dp,
-							    &old_handle));
-			if (r == EFI_SUCCESS &&
+			ret = EFI_CALL(efi_locate_device_path(protocol, &dp,
+							      &old_handle));
+			if (ret == EFI_SUCCESS &&
 			    dp->type == DEVICE_PATH_TYPE_END) {
 				EFI_PRINT("Path %pD already installed\n",
 					  protocol_interface);
-				r = EFI_ALREADY_STARTED;
+				ret = EFI_ALREADY_STARTED;
 				break;
 			}
 		}
-		r = EFI_CALL(efi_install_protocol_interface(
-						handle, protocol,
-						EFI_NATIVE_INTERFACE,
-						protocol_interface));
-		if (r != EFI_SUCCESS)
+		ret = EFI_CALL(efi_install_protocol_interface(handle, protocol,
+							      EFI_NATIVE_INTERFACE,
+							      protocol_interface));
+		if (ret != EFI_SUCCESS)
 			break;
 		i++;
 	}
-	efi_va_end(argptr);
-	if (r == EFI_SUCCESS)
-		return EFI_EXIT(r);
+	if (ret == EFI_SUCCESS)
+		goto out;
 
 	/* If an error occurred undo all changes. */
-	efi_va_start(argptr, handle);
 	for (; i; --i) {
-		protocol = efi_va_arg(argptr, efi_guid_t*);
-		protocol_interface = efi_va_arg(argptr, void*);
+		protocol = efi_va_arg(argptr_copy, efi_guid_t*);
+		protocol_interface = efi_va_arg(argptr_copy, void*);
 		EFI_CALL(efi_uninstall_protocol_interface(*handle, protocol,
 							  protocol_interface));
 	}
-	efi_va_end(argptr);
 
-	return EFI_EXIT(r);
+out:
+	efi_va_end(argptr_copy);
+	return ret;
+
 }
 
 /**
- * efi_uninstall_multiple_protocol_interfaces() - uninstall multiple protocol
- *                                                interfaces
- * @handle: handle from which the protocol interfaces shall be removed
+ * efi_install_multiple_protocol_interfaces() - Install multiple protocol
+ *                                              interfaces
+ * @handle: handle on which the protocol interfaces shall be installed
  * @...:    NULL terminated argument list with pairs of protocol GUIDS and
  *          interfaces
  *
- * This function implements the UninstallMultipleProtocolInterfaces service.
+ *
+ * This is the function for internal usage in U-Boot. For the API function
+ * implementing the InstallMultipleProtocol service see
+ * efi_install_multiple_protocol_interfaces_ext()
+ *
+ * Return: status code
+ */
+efi_status_t EFIAPI
+efi_install_multiple_protocol_interfaces(efi_handle_t *handle, ...)
+{
+	efi_status_t ret;
+	efi_va_list argptr;
+
+	efi_va_start(argptr, handle);
+	ret = efi_install_multiple_protocol_interfaces_int(handle, argptr);
+	efi_va_end(argptr);
+	return ret;
+}
+
+/**
+ * efi_install_multiple_protocol_interfaces_ext() - Install multiple protocol
+ *                                                  interfaces
+ * @handle: handle on which the protocol interfaces shall be installed
+ * @...:    NULL terminated argument list with pairs of protocol GUIDS and
+ *          interfaces
+ *
+ * This function implements the MultipleProtocolInterfaces service.
  *
  * See the Unified Extensible Firmware Interface (UEFI) specification for
  * details.
  *
  * Return: status code
  */
-static efi_status_t EFIAPI efi_uninstall_multiple_protocol_interfaces(
-			efi_handle_t handle, ...)
+static efi_status_t EFIAPI
+efi_install_multiple_protocol_interfaces_ext(efi_handle_t *handle, ...)
 {
 	EFI_ENTRY("%p", handle);
-
+	efi_status_t ret;
 	efi_va_list argptr;
+
+	efi_va_start(argptr, handle);
+	ret = efi_install_multiple_protocol_interfaces_int(handle, argptr);
+	efi_va_end(argptr);
+	return EFI_EXIT(ret);
+}
+
+/**
+ * efi_uninstall_multiple_protocol_interfaces_int() - wrapper for uninstall
+ *                                                  multiple protocol
+ *                                                  interfaces
+ * @handle: handle from which the protocol interfaces shall be removed
+ * @argptr: va_list of args
+ *
+ * Core functionality of efi_uninstall_multiple_protocol_interfaces
+ * Must not be called directly
+ *
+ * Return: status code
+ */
+static efi_status_t EFIAPI
+efi_uninstall_multiple_protocol_interfaces_int(efi_handle_t handle,
+					       efi_va_list argptr)
+{
 	const efi_guid_t *protocol;
 	void *protocol_interface;
-	efi_status_t r = EFI_SUCCESS;
+	efi_status_t ret;
 	size_t i = 0;
+	efi_va_list argptr_copy;
 
 	if (!handle)
-		return EFI_EXIT(EFI_INVALID_PARAMETER);
+		return EFI_INVALID_PARAMETER;
 
-	efi_va_start(argptr, handle);
+	efi_va_copy(argptr_copy, argptr);
 	for (;;) {
 		protocol = efi_va_arg(argptr, efi_guid_t*);
 		if (!protocol)
 			break;
 		protocol_interface = efi_va_arg(argptr, void*);
-		r = efi_uninstall_protocol(handle, protocol,
-					   protocol_interface);
-		if (r != EFI_SUCCESS)
+		ret = efi_uninstall_protocol(handle, protocol,
+					     protocol_interface);
+		if (ret != EFI_SUCCESS)
 			break;
 		i++;
 	}
-	efi_va_end(argptr);
-	if (r == EFI_SUCCESS) {
+	if (ret == EFI_SUCCESS) {
 		/* If the last protocol has been removed, delete the handle. */
 		if (list_empty(&handle->protocols)) {
 			list_del(&handle->link);
 			free(handle);
 		}
-		return EFI_EXIT(r);
+		goto out;
 	}
 
 	/* If an error occurred undo all changes. */
-	efi_va_start(argptr, handle);
 	for (; i; --i) {
-		protocol = efi_va_arg(argptr, efi_guid_t*);
-		protocol_interface = efi_va_arg(argptr, void*);
+		protocol = efi_va_arg(argptr_copy, efi_guid_t*);
+		protocol_interface = efi_va_arg(argptr_copy, void*);
 		EFI_CALL(efi_install_protocol_interface(&handle, protocol,
 							EFI_NATIVE_INTERFACE,
 							protocol_interface));
 	}
+	/*
+	 * If any errors are generated while the protocol interfaces are being
+	 * uninstalled, then the protocols uninstalled prior to the error will
+	 * be reinstalled using InstallProtocolInterface() and the status code
+	 * EFI_INVALID_PARAMETER is returned.
+	 */
+	ret = EFI_INVALID_PARAMETER;
+
+out:
+	efi_va_end(argptr_copy);
+	return ret;
+}
+
+/**
+ * efi_uninstall_multiple_protocol_interfaces() - uninstall multiple protocol
+ *                                                interfaces
+ * @handle: handle from which the protocol interfaces shall be removed
+ * @...:    NULL terminated argument list with pairs of protocol GUIDS and
+ *          interfaces
+ *
+ * This function implements the UninstallMultipleProtocolInterfaces service.
+ *
+ * This is the function for internal usage in U-Boot. For the API function
+ * implementing the UninstallMultipleProtocolInterfaces service see
+ * efi_uninstall_multiple_protocol_interfaces_ext()
+ *
+ * Return: status code
+ */
+efi_status_t EFIAPI
+efi_uninstall_multiple_protocol_interfaces(efi_handle_t handle, ...)
+{
+	efi_status_t ret;
+	efi_va_list argptr;
+
+	efi_va_start(argptr, handle);
+	ret = efi_uninstall_multiple_protocol_interfaces_int(handle, argptr);
 	efi_va_end(argptr);
+	return ret;
+}
+
+/**
+ * efi_uninstall_multiple_protocol_interfaces_ext() - uninstall multiple protocol
+ *                                                    interfaces
+ * @handle: handle from which the protocol interfaces shall be removed
+ * @...:    NULL terminated argument list with pairs of protocol GUIDS and
+ *          interfaces
+ *
+ * This function implements the UninstallMultipleProtocolInterfaces service.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification for
+ * details.
+ *
+ * Return: status code
+ */
+static efi_status_t EFIAPI
+efi_uninstall_multiple_protocol_interfaces_ext(efi_handle_t handle, ...)
+{
+	EFI_ENTRY("%p", handle);
+	efi_status_t ret;
+	efi_va_list argptr;
 
-	/* In case of an error always return EFI_INVALID_PARAMETER */
-	return EFI_EXIT(EFI_INVALID_PARAMETER);
+	efi_va_start(argptr, handle);
+	ret = efi_uninstall_multiple_protocol_interfaces_int(handle, argptr);
+	efi_va_end(argptr);
+	return EFI_EXIT(ret);
 }
 
 /**
@@ -3785,9 +3889,9 @@ static struct efi_boot_services efi_boot_services = {
 	.locate_handle_buffer = efi_locate_handle_buffer,
 	.locate_protocol = efi_locate_protocol,
 	.install_multiple_protocol_interfaces =
-			efi_install_multiple_protocol_interfaces,
+			efi_install_multiple_protocol_interfaces_ext,
 	.uninstall_multiple_protocol_interfaces =
-			efi_uninstall_multiple_protocol_interfaces,
+			efi_uninstall_multiple_protocol_interfaces_ext,
 	.calculate_crc32 = efi_calculate_crc32,
 	.copy_mem = efi_copy_mem,
 	.set_mem = efi_set_mem,