efi_loader: add file/filesys support

fallback.efi (and probably other things) use UEFI's simple-file-system
protocol and file support to search for OS's to boot.

Signed-off-by: Rob Clark <robdclark@gmail.com>
[agraf: whitespace fixes, unsigned fixes]
Signed-off-by: Alexander Graf <agraf@suse.de>

3 files changed, 80 insertions, 0 deletions

diff --git a/include/efi.h b/include/efi.h
index 63cbdb6..a432c89 100644
--- a/include/efi.h
+++ b/include/efi.h
@@ -81,6 +81,8 @@ typedef struct {
 #define EFI_IP_ADDRESS_CONFLICT		(EFI_ERROR_MASK | 34)
 #define EFI_HTTP_ERROR			(EFI_ERROR_MASK | 35)
 
+#define EFI_WARN_DELETE_FAILURE	2
+
 typedef unsigned long efi_status_t;
 typedef u64 efi_physical_addr_t;
 typedef u64 efi_virtual_addr_t;
diff --git a/include/efi_api.h b/include/efi_api.h
index 0c36122..1aae963 100644
--- a/include/efi_api.h
+++ b/include/efi_api.h
@@ -666,4 +666,69 @@ struct efi_pxe {
 	struct efi_pxe_mode *mode;
 };
 
+#define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID \
+	EFI_GUID(0x964e5b22, 0x6459, 0x11d2, \
+		 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
+#define EFI_FILE_PROTOCOL_REVISION 0x00010000
+
+struct efi_file_handle {
+	u64 rev;
+	efi_status_t (EFIAPI *open)(struct efi_file_handle *file,
+			struct efi_file_handle **new_handle,
+			s16 *file_name, u64 open_mode, u64 attributes);
+	efi_status_t (EFIAPI *close)(struct efi_file_handle *file);
+	efi_status_t (EFIAPI *delete)(struct efi_file_handle *file);
+	efi_status_t (EFIAPI *read)(struct efi_file_handle *file,
+			u64 *buffer_size, void *buffer);
+	efi_status_t (EFIAPI *write)(struct efi_file_handle *file,
+			u64 *buffer_size, void *buffer);
+	efi_status_t (EFIAPI *getpos)(struct efi_file_handle *file,
+			u64 *pos);
+	efi_status_t (EFIAPI *setpos)(struct efi_file_handle *file,
+			u64 pos);
+	efi_status_t (EFIAPI *getinfo)(struct efi_file_handle *file,
+			efi_guid_t *info_type, u64 *buffer_size, void *buffer);
+	efi_status_t (EFIAPI *setinfo)(struct efi_file_handle *file,
+			efi_guid_t *info_type, u64 buffer_size, void *buffer);
+	efi_status_t (EFIAPI *flush)(struct efi_file_handle *file);
+};
+
+#define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID \
+	EFI_GUID(0x964e5b22, 0x6459, 0x11d2, \
+		 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
+#define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION 0x00010000
+
+struct efi_simple_file_system_protocol {
+	u64 rev;
+	efi_status_t (EFIAPI *open_volume)(struct efi_simple_file_system_protocol *this,
+			struct efi_file_handle **root);
+};
+
+#define EFI_FILE_INFO_GUID \
+	EFI_GUID(0x9576e92, 0x6d3f, 0x11d2, \
+		 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
+
+#define EFI_FILE_MODE_READ	0x0000000000000001
+#define EFI_FILE_MODE_WRITE	0x0000000000000002
+#define EFI_FILE_MODE_CREATE	0x8000000000000000
+
+#define EFI_FILE_READ_ONLY	0x0000000000000001
+#define EFI_FILE_HIDDEN		0x0000000000000002
+#define EFI_FILE_SYSTEM		0x0000000000000004
+#define EFI_FILE_RESERVED	0x0000000000000008
+#define EFI_FILE_DIRECTORY	0x0000000000000010
+#define EFI_FILE_ARCHIVE	0x0000000000000020
+#define EFI_FILE_VALID_ATTR	0x0000000000000037
+
+struct efi_file_info {
+	u64 size;
+	u64 file_size;
+	u64 physical_size;
+	struct efi_time create_time;
+	struct efi_time last_access_time;
+	struct efi_time modification_time;
+	u64 attribute;
+	s16 file_name[0];
+};
+
 #endif
diff --git a/include/efi_loader.h b/include/efi_loader.h
index 8752bcf..9cb0644 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -86,6 +86,8 @@ extern const efi_guid_t efi_guid_console_control;
 extern const efi_guid_t efi_guid_device_path;
 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;
 
 extern unsigned int __efi_runtime_start, __efi_runtime_stop;
 extern unsigned int __efi_runtime_rel_start, __efi_runtime_rel_stop;
@@ -163,6 +165,9 @@ int efi_net_register(void);
 /* Called by bootefi to make SMBIOS tables available */
 void efi_smbios_register(void);
 
+struct efi_simple_file_system_protocol *
+efi_fs_from_path(struct efi_device_path *fp);
+
 /* Called by networking code to memorize the dhcp ack package */
 void efi_net_set_dhcp_ack(void *pkt, int len);
 
@@ -191,6 +196,14 @@ efi_status_t efi_set_timer(struct efi_event *event, enum efi_timer_delay type,
 /* Call this to signal an event */
 void efi_signal_event(struct efi_event *event);
 
+/* open file system: */
+struct efi_simple_file_system_protocol *efi_simple_file_system(
+		struct blk_desc *desc, int part, struct efi_device_path *dp);
+
+/* open file from device-path: */
+struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp);
+
+
 /* Generic EFI memory allocator, call this to get memory */
 void *efi_alloc(uint64_t len, int memory_type);
 /* More specific EFI memory allocator, called by EFI payloads */