efi_loader: implement EFI_FILE_SYSTEM_INFO

Implement the information type EFI_FILE_SYSTEM_INFO in the service
GetInfo() of the EFI_FILE_PROTOCOL.

The volume label is not available in U-Boot. As a work-around use the
partition name instead.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

include/efi_api.h

@@ -889,6 +889,10 @@ struct efi_simple_file_system_protocol {
 	EFI_GUID(0x9576e92, 0x6d3f, 0x11d2, \
 		 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
 
+#define EFI_FILE_SYSTEM_INFO_GUID \
+	EFI_GUID(0x09576e93, 0x6d3f, 0x11d2, \
+		 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
+
 #define EFI_FILE_MODE_READ	0x0000000000000001
 #define EFI_FILE_MODE_WRITE	0x0000000000000002
 #define EFI_FILE_MODE_CREATE	0x8000000000000000
@@ -912,6 +916,15 @@ struct efi_file_info {
 	s16 file_name[0];
 };
 
+struct efi_file_system_info {
+	u64 size;
+	u8 read_only;
+	u64 volume_size;
+	u64 free_space;
+	u32 block_size;
+	u16 volume_label[0];
+};
+
 #define EFI_DRIVER_BINDING_PROTOCOL_GUID \
 	EFI_GUID(0x18a031ab, 0xb443, 0x4d1a,\
 		 0xa5, 0xc0, 0x0c, 0x09, 0x26, 0x1e, 0x9f, 0x71)

include/efi_loader.h

@@ -112,6 +112,8 @@ extern const efi_guid_t efi_guid_loaded_image;
 extern const efi_guid_t efi_guid_device_path_to_text_protocol;
 extern const efi_guid_t efi_simple_file_system_protocol_guid;
 extern const efi_guid_t efi_file_info_guid;
+/* GUID for file system information */
+extern const efi_guid_t efi_file_system_info_guid;
 extern const efi_guid_t efi_guid_device_path_utilities_protocol;
 
 extern unsigned int __efi_runtime_start, __efi_runtime_stop;

lib/efi_loader/efi_file.c

@@ -12,6 +12,9 @@
 #include <malloc.h>
 #include <fs.h>
 
+/* GUID for file system information */
+const efi_guid_t efi_file_system_info_guid = EFI_FILE_SYSTEM_INFO_GUID;
+
 struct file_system {
 	struct efi_simple_file_system_protocol base;
 	struct efi_device_path *dp;
@@ -472,6 +475,41 @@ static efi_status_t EFIAPI efi_file_getinfo(struct efi_file_handle *file,
 			info->attribute |= EFI_FILE_DIRECTORY;
 
 		ascii2unicode((u16 *)info->file_name, filename);
+	} else if (!guidcmp(info_type, &efi_file_system_info_guid)) {
+		struct efi_file_system_info *info = buffer;
+		disk_partition_t part;
+		efi_uintn_t required_size;
+		int r;
+
+		if (fh->fs->part >= 1)
+			r = part_get_info(fh->fs->desc, fh->fs->part, &part);
+		else
+			r = part_get_info_whole_disk(fh->fs->desc, &part);
+		if (r < 0) {
+			ret = EFI_DEVICE_ERROR;
+			goto error;
+		}
+		required_size = sizeof(info) + 2 *
+				(strlen((const char *)part.name) + 1);
+		if (*buffer_size < required_size) {
+			*buffer_size = required_size;
+			ret = EFI_BUFFER_TOO_SMALL;
+			goto error;
+		}
+
+		memset(info, 0, required_size);
+
+		info->size = required_size;
+		info->read_only = true;
+		info->volume_size = part.size * part.blksz;
+		info->free_space = 0;
+		info->block_size = part.blksz;
+		/*
+		 * TODO: The volume label is not available in U-Boot.
+		 * Use the partition name as substitute.
+		 */
+		ascii2unicode((u16 *)info->volume_label,
+			      (const char *)part.name);
 	} else {
 		ret = EFI_UNSUPPORTED;
 	}